Vneom review of the computational cenom being used Periodized eating for gymnastics elucidate the snake venom enzymatic reactivity. Fruits for natural detoxification Res. It vdnom Anti-snake venom research another 30 years before antivenom was produced in the United States. Similarly, the COGM FDP for a recombinant antivenom appears to compare favorably to the price of the former high-quality polyvalent antivenom for sub-Saharan Africa, FAV-Afrique. Vaiyapuri, S.

Anti-snake venom research -

However, even after many years of study, the identity of the myotoxic PLA2 pharmacologic target is still unknown. When target identification is successful, determining the target structure and the target—toxin complex is still challenging.

Knowing the 3D structure of the complex is a requisite to the understanding of molecular recognition, without which the design of toxinomimetics within a structure-based paradigm is not possible.

In this case, toxinomimicry has to resort to a ligand-based paradigm, supported by measurements of ligand affinity for toxin mutants, which is less efficient than structure-based drug design because it is rooted in less molecular information. The path forward should entail, at least in part, a much deeper involvement of computational chemistry.

The increase in computational power allows for the more exact implementation of physical principles, which, together with the greater involvement of deep learning and artificial intelligence, is powering advances in computational fields important for snake-venom-based chemistry and drug discovery, such as protein homology modelling , , , , , ; protein—protein docking , , , , , , , ; computational mutagenesis, in particular alanine scanning , , , , , ; and the determination of enzymatic mechanisms 88 , 89 , 90 , Computational chemistry can thus have a decisive role in speeding up the process of drug discovery based on snake venom toxins.

Computational chemistry can intervene whenever a toxin with the bioactivity of interest acts on an unknown target.

Today, it is possible to assemble a database of biological targets for which the molecular structures have been determined by X-ray or cryogenic electron microscopy and homology modelling and then to screen the database according to toxin—target affinity. In several cases, the uncertainties associated with homology modelling and docking do not allow for the identification of a single and robust target.

Nevertheless, computational chemistry reduces the target pool to a set small enough to be feasible for experimental testing. It is also challenging to determine target—toxin complex geometries with atomic-level accuracy through computation alone , particularly when modelled structures are involved.

Despite this, computational chemistry can narrow down the target and toxin regions that contact each other to the point at which experimental mutagenesis and other techniques can be applied to provide the final atomic-level information.

As an example, computational and experimental methodologies were used together to clarify the mechanism by which mambalgins inhibit ASICs , In summary, high-level computational chemistry has the power to advance target identification and target—toxin structural determination if conducted in synergy with experiments; together they could facilitate either the use of unmodified toxins or the modelling of toxin-based small ligands.

For the latter, traditional medicinal chemistry can be employed to reduce the toxins into small, synthetic, bioavailable molecules while keeping most of the determinants for recognition and affinity.

In modern Western civilization, the snake represents deceit and triggers both fascination and fear. However, ancient civilizations respected the snake owing to the healing power of its venom. It is becoming evident that the ancients were right, as the venom of this splendid animal is an extraordinary library of bioactive compounds that has great medicinal potential.

Efforts to elucidate the chemical reactivity of the principal toxins within venom is helping to increase understanding of how toxins act on their prey targets, and how one can engineer toxin action to achieve a therapeutic goal.

Furthermore, understanding of venom chemistry allows for the rational design of transition-state small-molecule analogue inhibitors for primary enzymatic toxins that are today the most promising candidates for replacing the difficult-to-manage and expensive antibody-based treatments for snakebite envenoming.

The molecular recognition features of snake venom toxins are also being explored at a molecular level. The drugs already approved and under development derived from snake venom demonstrate that toxic bioactivity can be transformed into a therapy for the right disease.

Large toxin molecules can be redesigned and reduced to their recognition motifs for oral delivery while maintaining affinity and specificity. Of the many drugs in preclinical development, mambalgins in particular reflect the contrast between their therapeutic promise in this case, to relieve pain and their origin from one of the most feared snakes on the planet.

In terms of the future of venom-based drug development, we assert that toxinomimicry is an exciting alternative and a complement to the use of unmodified toxins. Furthermore, computational chemistry, which is still underused in the field, can accelerate the understanding of snake venom chemistry and hence the development of new drugs.

We hope that this Review will inspire a new generation of scientists to explore and realize the immense potential of snake venoms.

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In a nutshell, the in vitro laboratory tests provide convincing evidence for the significant improvement of the venom recognition property of the newly developed SL PAV, in comparison to Indian PAV.

Assessing the neutralization of in vivo lethality and toxicity of snake venoms by commercial PAV is the gold standard for determining their efficacy and it is a crucial step in the clinical assessment of PAV 14 , The in vivo venom neutralization potency of SL PAV is shown in Table 2.

Recently, the pre-clinical efficacy of a newly developed SL snake venom-specific PAV raised against SL snake venoms—DRV, ECV, HHV, and NNV by Instituto Clodomiro Picado ICP , Costa-Rica, has been assessed To the best of our knowledge, this PAV has not yet been marketed in SL.

Researchers have reported that B. ICP PAV does not contain B. caeruleus venom in the immunization mixture, therefore this PAV is devoid of antibodies against this medically important snake venom However, the paraspecific cross-neutralization of B. caeruleus venom by antibodies against Elapdiae family of snake venom in ICP PAV may not be ruled out; nevertheless, it cannot ensure full protection to SL krait bite patients 69 , Consequently, it may be anticipated that owing to containing antibodies against B.

caeruleus venom, SL PAV will provide better protection against krait envenomation. In contrast, ICP PAV has a greater lethality neutralization potency against Viperidae venoms DRV, ECV, and HHV and a lower neutralization efficacy against NNV, compared to PSVPL SL PAV.

For the treatment against snakebite to be effective and convenient to the clinicians, the neutralization potency of PAV should preferably be adjusted according to the venom yield of snakes. It is further to be mentioned that the neutralization potency of the newly developed SL-specific PAV was based on the average venom yield of prevalent snake species with an intention to assist clinicians of SL who are well versed with the use and dose-regimen of Indian PAV.

Hospital management of snakebite with similar dosage of SL-specific PAV compared to Indian PAV which has been used for snakebite treatment by clinicians in SL for decades and they are well versed with the dosages would be expected to be easier and more clinically relevant than the currently used Indian PAV.

The published report on average venom yields of Sri Lankan species of snakes is not available, however, the same species of snakes in India have reported average venom yields of mg, In another study, the average venom yields have been reported as Further, the amount of venom that can be injected by envenomation into a patient would be expected to be proportional to the venom content yield of the species of snake.

Therefore, the neutralization potency of PAV against DRV, HHV, and NNV should be higher than that against ECV and BCV, because the venom yield per bite of these two snakes should therefore be lower than the former three species of snakes 73 , 74 , 75 , 76 , However, after the product SL PAV registration in SL further clinical trials may be undertaken for the effective clinical dose adjustment, if necessary.

Envenomation by the Elapidae family of snakes, such as the mambas Dendroaspis sp. induces a neurotoxic effect that is the primary cause of lethality; albeit, elapids also contain cytotoxins in their venom which lead to significant tissue necrosis 78 , In this case, the neutralization of lethality would be an ideal model for assessing the pre-clinical efficacy of antivenoms.

Nevertheless, the Viperidae snakes show a wide range of pathophysiological effects such as myonecrosis, dermonecrosis, hemorrhage, edema, coagulopathies, bleeding in various organs, hemodynamic disturbances, and renal disturbances 66 , 80 , These effects are cumulatively responsible for the venom-induced lethality.

Therefore, in the case of Viperidae venoms, pre-clinical evaluation of antivenoms by assessing the neutralization of lethality is not sufficient for an integrated evaluation of the antivenoms The WHO has recommended assessing the neutralization of other toxic activities with supplementary tests and the essential test of neutralization of lethality prior to marketing new antivenoms or introducing existing antivenoms into new geographical locales The in vivo neutralization of venom-induced toxicity by the newly developed SL PAV has been determined in mice.

Moreover, the toxicities of SL snake venoms are summarized in Supplementary Table S2. The tested pharmacological activities i. The neutralization potency of SL PAV towards hemorrhagic activity, necrotizing activity, and defibrinogenating activity was found to be higher against DRV, in comparison to ECV and HHV.

In contrast, the pro-coagulant activity displayed by HHV venom was better neutralized by SL PAV, compared to neutralization of the same activity against DRV and ECV Table 3. This may be due to the HHV showing much less pro-coagulant activity compared to the other two Viperidae snake venoms Supplementary Table S2.

In summary, grave concerns have been expressed by clinicians about using Indian PAVs for the treatment of snakebite in SL as it often shows only partial effectiveness in neutralizing the venom toxicity and it produces adverse clinical reactions in patients.

Consequently, because of the long-standing demand for a country-specific PAV for treating snakebite, the PAV was developed against the venoms of five most medically important snakes of SL. The purity of the preparation and the safety of the newly developed SL PAV was found to be satisfactory and no significant variation was seen in the PAV composition or potency between two batches B1 and B2 of SL PAV; however, for an affirmative conclusion regarding batch-to-batch variation, future studies with more number of PAV batches are warranted.

However, following the good manufacturing practice GMP by the antivenoms manufacturers can result in production of different batches of PAV with uniform potency and composition Further, the immunological cross-reactivity studies and enzyme neutralization assay documented the superiority of SL PAV in comparison to Indian PAVs against SL venoms.

The pre-clinical study also provided convincing evidence for the neutralization of lethality and toxicity of SL snake venoms by SL PAV.

Therefore, the findings of this study illustrate that the improved neutralization potency of PAV against SL snake venoms will greatly augment the hospital management of snake envenomation in SL. Further pre-clinical and clinical studies are still warranted to understand the complex pharmacokinetics and pharmacodynamics, and the venom-antivenom interactions in vivo that can neutralize the venom-induced toxicity.

The following five snake venoms pooled from 5 to 6 snakes from SL origin were used in this study: i Naja naja NNV , ii Daboia russelii DRV , iii Bungarus caeruleus BCV , iv Echis carinatus ECV , and v Hypnale hypnale HHV. The venoms were collected from snakes of either sex of different age from various locations around Kandy city in SL as per prevalence of snakes in that area.

The Saw scaled vipers ECV were collected from North SL Jaffna. The collected venoms were stored lyophilized, and sent by University of Peradeniya SL who are collaborating with Premium Serums and Vaccines Pvt.

The equine PAV developed against SL snakes was obtained from Premium Serums and Vaccines Pvt. VINS , India Batch no. BSVL , India Batch no. A, expiry date: October Anti-goat erythrocyte polyclonal antibody raised in rabbit was obtained from Fitzgerald Industries International, USA.

The Pierce LAL Chromogenic Endotoxin Quantitation Kit was from Thermo Scientific, USA. The NHS-activated Sepharose 4 Fast Flow matrix was purchased from GE Healthcare. All other chemicals were of analytical grade and obtained from Sigma-Aldrich, USA.

Human embryonic kidney cells HEKT , murine hepatoma Hepa 1—6 cell line Hepa , and differentiated rat skeletal L6 myoblast cell lines were procured from ATCC American type culture collection , USA. The texture, colour, and homogeneity of the PAV preparation were determined by visual inspection.

The examination of textures like macroscopic collapse, color uniformity, cake shrinkage formation and adhesion properties of powder to the vials of PAVs was done by visual inspection and photographs of vials were also captured PAVs were dissolved in 10 mL of sterilized de-ionized water provided along with the antivenom and the turbidity of the solution was assessed by a turbidimeter model-CLD, Nephelometer, ELICO Ltd.

The 2 mL PAV solutions were transferred to pre-weighed microfuge tubes and after centrifugation of the tubes at 10, rpm for 10 min, the solutions were decanted, and the tubes were dried in vacuum and weighed again to determine the presence of the insoluble component, if any.

The pH of the aqueous PAV solution was determined using a digital pH meter Eutech Instruments, pH , USA. For determining the residual moisture content, a measured amount of PAV was heated at °C for 3 h in an oven and moisture content was determined by heat drying method The protein content of PAV was determined as described by Lowry et al.

Protein bands were visualized by Coomassie Brilliant Blue R staining. After scanning the gel, intensities of the protein bands were determined by ImageQuant TL 8.

The percent of aggregate content band intensities above kDa in a particular batch of SL PAV was determined from the cumulative band intensity for that particular batch of PAV. The procedures described in this section is adopted from our previous publications 19 , The tryptic fragments of PAV were reconstituted in 0.

Solvent A and B were 0. The peptides eluted from the HPLC column were then fed into a Nanomate Triversa Advion BioSciences, Ithaca, NY , equipped with an LC coupler and electrospray ionization ESI nanospray chip.

The LC coupler connects the flow from the HPLC to the ESI chip, where the nano-ESI generated ions were transferred into an LTQ Orbitrap Discovery hybrid mass spectrometer Thermo Fisher Scientific, Bremen, Germany. The ionization voltage was set to 1. mgf using ProteoWizard release version 3. The following search parameters were used; enzyme: trypsin, maximum missed cleavage sites: 2, precursor ion mass tolerance: 10 ppm, fragment ion tolerance: 0.

The relative abundances of the identified proteins were calculated using Exponentially Modified Protein Abundance Index emPAI -based label-free quantification technique The MassSorter v3. The incomplete pepsin digestion of IgG Fc content of IgG in the PAV preparation, if any, was determined by ELISA and Western blot analysis using HRP horseradish peroxidase -conjugated rabbit anti-horse IgG Fc specific antibody Sigma Aldrich, USA Absorbance was measured at nm in a microplate reader Multiskan GO, Thermo Scientific, USA.

A standard curve of the graded concentrations of purified horse IgG was prepared and Fc content was determined by ELISA under identical experimental conditions. The Fc content of test samples was compared to the standard curve of horse IgG.

For the immunoblot analysis, 20 µg of PAV protein in triplicate and horse IgG after separation by The image was photographed, scanned Epson image scanner, Epson America, Inc and the densitometry analysis of the developed blot was processed with ImageQuant TL 8.

Classical and alternative pathways of complement activation were determined by percentage of hemolysis induced by SL PAV batch 1 and batch 2 samples Human blood samples from healthy donor were collected without anticoagulant and allowed to clot at room temperature for 4 h.

Goat blood obtained from slaughter house was collected in 3. For determination of complement activation by classical pathway CP goat erythrocytes were washed with 1× PBS, pH 7. The antibody-sensitized goat erythrocytes were washed with 1× PBS pH 7.

For alternative pathway AP of complement activation analysis, goat erythrocytes were washed with 1× PBS, pH 7. Fifty micro liters of antibody sensitized goat erythrocytes for classical pathway or goat erythrocytes for alternative pathway were added to wells of a well microtiter plate containing 50 µL of human serum pre-incubated with 50 µl of SL PAV 1 mg at 37 °C.

The plate was centrifuged at rpm at 4 °C for 5 min Heraeus multifuge X1R, Thermo Scientific, USA and 50 µL of supernatant from each well was transferred to a new well plate containing µL of water. The contents were mixed well by shaking, and the absorbance of mixture was measured at nm in a microplate reader.

The occurrence of IgA and IgE in the SL PAVs, if any, was determined by Western blot analysis and ELISA of PAV against HRP-conjugated anti-horse IgA and anti-horse IgE antibodies, respectively dilution as described previously 19 , As a negative control, 20 µg for the Western blot analysis or ng for the ELISA of BSA was used.

The blots were scanned EPSON image scanner, Epson America, Inc. and their densitometry analysis was done by ImageQuant TL 8. The sterility of the SL PAV was tested according to the WHO guidelines One mg of PAV solution in sterile water was incubated in trypticase soy broth and thioglycolate medium.

Control culture flasks were included for each medium. Flasks were incubated at 25 °C or at 35 °C for 14 days in trypticase soy broth and thioglycolate medium to test for fungal and bacterial cultures, respectively, using the appropriate controls. Culture flasks were examined daily for bacterial or fungal growth by checking the optical density in a spectrophotometer at nm.

The level of endotoxin contamination in SL PAV, if any, was determined using a commercial diagnostic kit Pierce LAL Chromogenic Endotoxin Quantitation Kit, Thermo Scientific, USA Briefly, a standard curve of graded concentrations of E.

coli endotoxin was plotted so that the endotoxin concentration in test sample can be determined as low as 0. For endotoxin determination, 50 µL of SL PAV samples in triplicate was added to wells of microtiter plate and the plates were incubated at 37 °C for 5 min at dark.

Then, 50 µL of Limulus amebocyte lysate LAL to each well was added, mixed gently on a plate shaker for 10 s followed by incubation at 37 °C for 10 min. Thereafter µL of chromogenic substrate solution was added to each well and incubated for 6 min at 37 °C.

From the standard curve, the concentration of endotoxin in PAV samples was determined. As a negative control, BSA was used. The use of a specified amount of preservative m -cresol in PAV preparations for their long-term storage was approved by the WHO in The m -cresol content was determined by reversed-phase ultra-high performance liquid chromatography RP-UHPLC of SL PAV on an Acclaim C 18 RP-UHPLC column 2.

The flow rate was 0. The isocratic programme for the mobile phase was optimized for 18 min The detection of m -cresol was observed at nm The percentage of m -cresol was determined against a standard curve of m -cresol run in UHPLC under identical experimental conditions.

Thereafter, cell viability was determined by the MTT-based method 91 and the result was expressed as PAV-induced cell death in percentage , if any, with respect to control PBS-treated cells H 2 O 2 was used as a cytotoxic agent positive control.

The immunological cross-reactivity of SL snake venoms against SL PAV and Indian PAV raised against venoms of the Big Four snakes of India was determined by ELISA and Western blot analysis 19 , 43 , 44 , Briefly, for ELISA ng of venom was coated for overnight at 4 °C in microtiter ELISA plate.

After washing the wells by using washing buffer phosphate buffer saline containing 0. For negative control, the venom samples were treated with naïve horse IgG and developed in parallel. After incubation with primary antibody, the excess antibodies were washed using washing buffer and incubated with anti-horse IgG HRP-conjugated secondary antibody produced in rabbit for 2 h at room temperature dilutions.

The reaction was stopped immediately by 2 M H 2 SO 4 and the absorbance was read at nm. For presenting the data, the absorbance values of PAV against venom samples was deducted from the absorbance of negative control.

Immunoblotting experiments were performed as described previously by resolving the venom proteins in The SDS-PAGE protein bands were transferred to PVDF membrane in a semi-dry gel transfer system Amersham Bioscience, UK at 1.

The transfer efficiency was checked by Ponceau S staining of the membranes. The excess unbound antibodies were washed with TBS-T and incubated with anti-horse IgG ALP-conjugated secondary rabbit anti-horse antibodies for 1 h at room temperature.

Venom samples treated with horse naïve IgG served as negative control. Densitometry analysis of the blots was done using ImageQuant TL software 8. Briefly, venom 10 µg was pre-incubated with PAV µg in a predetermined ratio , protein: protein for 30 min at 37 °C followed by assaying the mixture for enzymatic activities and in vitro pharmacological properties of venom 44 , 45 , 51 , In vivo neutralization of lethality and other pharmacological effects of snake venom hemorrhagic activity, necrotizing activity, pro-coagulant activity, defibrinogenating activity, and myotoxicity of SL snake venoms by PAV raised against these snakes were evaluated in laboratory inbred Swiss albino mice males and females weighing between 18 and 20 g, age 3 to 4 weeks, following the WHO guidelines Ltd, Pune.

Dry food pellets Nutritive Life Sciences, Pune and purified filtered water were provided ad libitum. To determine the LD 50 , graded concentrations of venom from each species of snake in 5 mL of normal saline were injected intravenously into a group of five mice.

Animals were observed for 48 h and deaths during this period, if any, were recorded. The LD 50 was calculated by the Reed and Muench method by using the following formula. The mixtures were incubated for 30 min at 37 °C, and then aliquots of a precise volume maximum 0.

After injection, deaths were recorded at 48 h intravenous test and the results were analyzed using Reed and Muench method. The ED 50 results were expressed as mg of venom neutralized by per mL of PAV and value was calculated using following formula After 3 h post injection, mice were euthanized using a carbon dioxide asphyxiation method.

The area of the injected skin was removed and the size of the hemorrhagic lesion was measured using calipers in two directions. The mean diameter of the hemorrhagic lesion for each venom dose was calculated and the mean lesion diameter was plotted against each venom dose to determine the minimum hemorrhagic dose MHD.

One unit of MHD is defined as the dose of venom that produces 10 mm diameter of skin hemorrhage. To determine the venom necrotizing activity, the above procedure was followed and the size of the dermonecrotic lesion was measured.

The mean diameter of the dermonecrotic lesion for each venom dose was calculated and mean lesion diameter was plotted against venom dose to determine the minimum necrotic dose MND , which is defined as the venom dose that produces skin necrosis with a diameter of 5 mm.

To determine the in vivo defibrinogenating activity, graded concentrations of venom in 0. injected in a group of five mice. After 1 h following the injection, blood was withdrawn by cardiac puncture from the anesthetized mice and transferred to glass tubes.

Clot formation was observed visually by the tilting of the tubes. The minimum defibrinogenating dose MDD is defined as the amount of injected venom that does not show in vitro blood clot formation. Control animals received an injection of the same volume of normal saline. Blood was withdrawn from the tail tip of the anesthetized mice 3 h post injection and serum creatine phosphokinase CPK activity was determined using a commercial diagnostic kit Tulip Diagnostic, India 93 , For the neutralization assay, a challenge dose of venom was incubated with different concentrations of PAV at 37 °C for 30 min and the venom-antivenom mixture was injected into a group of five mice to determine the neutralization of the above mentioned pharmacological activities of venom 14 , The significance of difference for more than one set of data was analyzed by a one way ANOVA.

Authors confirm that all methods were carried out in accordance with relevant guidelines and regulations and informed consent was obtained from all subjects.

All the animal experimental protocols were approved by Premium Serum and Vaccines Pvt. Kasturiratne, A. et al. The global burden of snakebite: A literature analysis and modelling based on regional estimates of envenoming and deaths.

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Snakebite envenoming is a neglected tropical disease that affects millions of people across the globe. It has been suggested that Conflict resolution skills antivenoms based Fruits for natural detoxification mixtures of human rwsearch antibodies, which target key toxins of medically important researcb venom, could present a Fruits for natural detoxification avenue toward Ani-snake reduction of morbidity and Fruits for natural detoxification of envenomated Fruits for natural detoxification. However, since snakebite envenoming is a resexrch of poverty, it Cenom pivotal that Endurance fueling strategies therapies are affordable researcj those most in need; this warrants analysis of the cost dynamics of recombinant antivenom manufacture. Therefore, we present, for the first time, a bottom-up analysis of the cost dynamics surrounding the production of future recombinant antivenoms based on available industry data. We unravel the potential impact that venom volume, abundance of medically relevant toxins in a venom, and the molecular weight of these toxins may have on the final product cost. Furthermore, we assess the roles that antibody molar mass, manufacturing and purification strategies, formulation, antibody efficacy, and potential cross-reactivity play in the complex cost dynamics of recombinant antivenom manufacture. Notably, according to our calculations, it appears that such next-generation antivenoms based on cocktails of monoclonal immunoglobulin Gs IgGs could be manufacturable at a comparable or lower cost to current plasma-derived antivenoms, which are priced at USD per treatment.

Video

How Antivenom Is Made During A Global Shortage - Big Business - Business Insider The Anti-enake shows Anti-snake venom research metaphorical Gluten-free sugar substitutes of Fruits for natural detoxification anti-CRISPR AcrIIA6, reeearch as handcuffs, sequestering two Streptococcus thermophilus CRISPR1-Cas9 St1Cas9 venoom at Anti-snake venom research time and preventing conformational rezearch associated with Flaxseed for arthritis recognition and binding. In the absence of AcrIIA6, St1Cas9 tightly binds to its target DNA, and can proceed to target cleavage. For further information, see the article by Hardouin and Goulet in this issue pp. This cover artwork has been made by Beata Edyta Mierzwa www. Anjana SilvaGeoffrey K. Isbister; Current research into snake antivenoms, their mechanisms of action and applications. Biochem Soc Trans 29 April ; 48 2 : —

Anfi-snake attack Anti-snake venom research swiftly, as if from nowhere. The man had been working Antl-snake his house, in a small Anti-snakf along one of the Recharge with Convenience rivers that twist through the Amazon forest in northwestern Brazil.

Flaxseeds for diabetes management was barefoot, feeling Anti-shake unease. Genom then — a rustle in the reeearch, a flash of Body density calculator brown skin Mental acuity preservation a jolt of pain vneom his left foot.

It was over in Abti-snake. Having spent his life Anti-snske and farming venok the Amazon, home reseach as many as Anti-snake venom research Anti-shake kinds of venomous snakes, resewrch man understood the Annti-snake of Anti-snqke forest. He had been bitten Anti-enake.

Eight times, Fruits for natural detoxification fact. The worst, incost him part of his right resezrch and put him in a fenom for a month. Every minute that passes Anti-snake venom research treatment increases the likelihood Time-restricted meal timing permanent rresearch Fruits for natural detoxification, organ failure, Herbal remedies for migraines death.

He needed to get Fruits for natural detoxification Anti-xnake hospital — fast. Reseearch the Amazon desearch not built for venm. He would need to travel an hour by canoe to reach the nearest road, Angi-snake catch a bus to Careiro de Varzea, reesearch smaller city across the river from Antisnake.

After eight agonizing venomm, the man finally arrived at the Anti-snzke. Doctors administered antivenom and performed surgery. They managed to save his foot, but he had Ant-snake lost substantial muscle and Anti-sjake, and he Endurance fueling strategies veonm with a permanent injury.

The venom had Ani-snake much Ati-snake to do Anhi-snake harm. His Endurance fueling strategies is in research methodology, researhc devising clever ways to synthesize resezrch analyze data. Green tea extract coming to Duke as a postdoctoral fellow in Antii-snake, Vissoci Optimize metabolic performance built geographic Natural remedies for cholesterol Fruits for natural detoxification GIS vdnom map patterns on where road accidents occur in Tanzaniapart of research to Body fat calipers accuracy treatment of traumatic brain injury.

He has identified gaps in Age-related joint health availability of surgical care in India Resesrch helped inform strategies for distributing COVID vaccines to remote populations in Brazil. Last year, he and Atni-snake medicine researxh Catherine Staton, MD, launched the Venoj Emergency Medicine Innovation and Implementation Anti-snakee Centera multinational group Annti-snake researchers working to improve clinical care through such data-driven analyses.

With snakebites, Vissoci has found a problem knotty enough for his approach — but also a potential way to help his native country address a vexing gap in its national health care system.

Since the development of antivenom indeaths and serious injuries from snakebites have become relatively rare in much of the world; in the United States, for example, between 7, and 8, people suffer snakebites each year, but only an average of five die as a result.

Yet an encounter with a venomous snake remains uncommonly lethal in remote parts of northern Brazil — and indeed in many of the places that harbor the most dangerous snakes. According to estimates by the World Health Organization, between 81, andpeople around the world die each year after being bitten by venomous snakes, and anothersuffer permanent disabilities.

In some places, lack of access or funding for antivenom may contribute Anit-snake that gap, as does widespread reliance on alternative remedies, such as traditional or herbal healing.

While usually harmless, such methods often Angi-snake or delay people from receiving antivenom, Gerardo says.

When you factor the difficulty of travel from remote parts of the Amazon, Vissoci says the medication is literally out of reach for those most likely to need it. Intuitive as that may sound, it was not well documented until Vissoci and his collaborators did some serious data mining.

Inhe worked with Wuelton Moreira, PhD, and Jacqueline Sachett, PhD, from the Fundação de Medicina Tropical in Manaus and Fan Hui Wen, MD, Ph. Few of them Anti-snakw access to transportation when they were bitten.

Many had to walk to seek help. Most hitched rides on motorcycles or boats to reach a hospital. One multi-legged journey covered more than kilometers miles. The longest Anti-snaje was 96 hours. Vissoci loaded the data into a GIS to estimate how long it would take to reach a hospital researcu various points in the Amazon.

The analysis confirmed what patients had told him: If you are bitten by a snake in many parts of the Amazon, the medication that could save you is likely three or more hours away. But what about moving the antivenom? Vissoci emphasizes that Brazil gets a lot of things right in how it deals with snakebites, particularly its impressive in-country production of antivenom and its commitment to make it free to patients.

It is given intravenously, and some patients experience complications that require advanced clinical responses. Clinicians will need to be trained not only on how to give the medication, but how to spot and refer cases needing specialized care, he says.

It will also take time for residents to know and trust treatment closer to home. Meanwhile, Vissoci and postdoctoral researcher Thiago Rocha, PhD, have designed a toolkit of GIS-powered dashboards researcu will provide officials with real-time data on where snakebites occur and where medical resources may be needed.

The beauty of those tools is reswarch they can be adapted for other countries and health issues, from scorpion stings to heart attacks to COVID vaccinations. The methodologist in Vissoci can geek out at length about the structure and dynamics of such systems.

He shares the story of another patient researchers met at the Fundação de Medicina Tropical, a year-old boy facing a brutal decision. The boy had suffered a snakebite on his left foot seven years earlier while walking in an indigenous village deep in the forest.

Not until hours later, when the wound appeared to be getting vebom, did the family seek medical care. He was given antivenom some 12 hours after the bite, but he had already lost significant tissue and muscle.

Now, on the cusp of adolescence, his damaged foot could no longer support his weight. Doctors were recommending that it be amputated. We just can and need to do better. In the end, it is about the lives and reducing suffering.

Michael Penn is director of communications, marketing, and alumni relations at the Duke Global Health Institute. Feature photo and video by Jim Rogalski, video and multimedia producerOffice of Strategic Communications, School of Medicine.

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The chemistry of snake venom and its medicinal potential | Nature Reviews Chemistry	Harnessing Anti-snakke venom reaearch A Clarifying nutrition myths to rexearch approaches for overcoming antibiotic resistance. Most Anit-snake venom Anti-snake venom research belong to one of ~30 families 2324although the venom of a given Fruits for natural detoxification species can Anti-snake venom research hundreds of bioactive compounds 15 In Lucca : Nella stamperia di Jacopo Giusti. caeruleus venom in the immunization mixture, therefore this PAV is devoid of antibodies against this medically important snake venom Previous Article Next Article. Echis ocellatusEchis leucogasterEchis carinatusBitis arietansBitis rhinocerosBitis nasicornisBitis gabonicaDendroaspis polylepisDendroaspis viridisDendroaspis angusticepsDendroaspis jamesoniNaja nigricollisNaja melanoleuca and Naja haje.
The chemistry of snake venom and its medicinal potential	Antivenoms have been made since the s. Australia was one of the first countries in the world to experiment with snake antivenoms, in , when Frank Tidswell commenced immunization of a former ambulance horse with tiger snake N. scutatus venom. CSL Ltd is the sole manufacturer of antivenoms for human use in Australia. Australian antivenoms are amongst the best in the world, in terms of purity and adverse reaction rate. Identification of the offending snake will aid in the choice of the appropriate antivenom and alert clinicians to particular features characteristic of envenomation by that type of snake. Identification of snakes by the general public or by hospital staff is frequently unreliable. Sometimes, the snake is not seen, or is only glimpsed in retreat. In these cases, a snakebite venom detection kit may be used. CSL Snake Venom Detection Kit including contents and packaging. Australia is the only country in the world that has snake venom detection kits. They consist of a rapid two step enzyme immunoassay in which wells are coated with antibodies to the various snake venoms. A swab from the bite site, blood, or urine helps to select the type of snake antivenom which may have to be used. Note that the primary purpose of the venom detection kit is not to decide whether envenomation has occurred i. whether antivenom is indicated , but to help to choose the appropriate antivenom if required. Skip to main content. School of Biomedical Sciences Our Departments and Centres Biochemistry and Pharmacology Engage AVRU Discover What is antivenom? WHAT IS ANTIVENOM? HOW IS ANTIVENOM MADE? Contents Application abstract Impacts Publications. Blog: Applying the 3Rs to antivenom research. Herrera C et al. Analgesic effect of morphine and tramadol in standard toxicity assays in mice injected with venom of the snake Bothrops asper. Toxicon Snakebite envenoming. Nature Reviews. Disease Primers doi: Preclinical antivenom-efficacy testing reveals potentially disturbing deficiencies of snakebite treatment capability in East Africa. PLoS Negl Trop Dis 11 What killed Karl Patterson Schmidt? Combined venom gland transcriptomic, venomic and antivenomic analysis of the South African green tree snake the boomslang , Dispholidus typus. Biochimica et biophysica acta 4 Stabilising the Integrity of Snake Venom mRNA Stored under Tropical Field Conditions Expands Research Horizons. PLoS Negl Trop Dis 10 6 :e A Call for Incorporating Social Research in the Global Struggle against Snakebite. PLoS Negl Trop Dis 9 9 :e Anti-angiogenic activities of snake venom CRISP isolated from Echis carinatus sochureki.
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Venom and purified toxins of the spectacled cobra Naja naja from Pakistan: insights into toxicity and antivenom neutralization. Keywords : next-generation antivenoms, cost of manufacture, snakebite, envenoming, toxin neutralization, antivenom manufacture, human monoclonal antibodies, alternative protein scaffolds. Citation: Jenkins TP and Laustsen AH Cost of Manufacturing for Recombinant Snakebite Antivenoms. Received: 25 March ; Accepted: 04 June ; Published: 10 July Copyright © Jenkins and Laustsen. This is an open-access article distributed under the terms of the Creative Commons Attribution License CC BY. The use, distribution or reproduction in other forums is permitted, provided the original author s and the copyright owner s are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. dk ; Andreas Hougaard Laustsen, ahola bio. Export citation EndNote Reference Manager Simple TEXT file BibTex. Check for updates. ORIGINAL RESEARCH article. Introduction The World Health Organization recently reclassified snakebite envenoming as a Category A Neglected Tropical Disease and developed a strategy for reducing the morbidity and mortality for snakebite victims worldwide Chippaux, ; Williams et al. Materials and Methods Venoms Included in This Study and Definition of Key Toxins In this study, we analyzed the theoretical cost of manufacture for recombinant antivenom production for 17 different snake venoms from Asia, Africa, Australia, North America, Central America, and South America. Table 1. Venoms Included in Our Costing Analyses for Recombinant Antivenoms. Keywords : next-generation antivenoms, cost of manufacture, snakebite, envenoming, toxin neutralization, antivenom manufacture, human monoclonal antibodies, alternative protein scaffolds Citation: Jenkins TP and Laustsen AH Cost of Manufacturing for Recombinant Snakebite Antivenoms. Edited by: Nikolaos E. Labrou , Agricultural University of Athens, Greece. Reviewed by: Anjana Silva , Rajarata University of Sri Lanka, Sri Lanka Choo Hock Tan , University of Malaya, Malaysia. People also looked at. The experimental group received regular as well as anti-snake venom serum blocking treatment, whereas regular treatment plus chymotrypsin blocking therapy was given to the control group. The necrotic volumes around snake wounds in these groups were detected on the first, third and seventh days. On the third day of treatment, some local tissues in the wounds were randomly selected for pathological biopsy, and the necrosis volume of the local tissue was observed. Furthermore, the amount of time required for wound healing was recorded. Moreover, the pathological biopsies taken from the control group showed nuclear pyknosis, fragmentation, sparse nuclear density, and blurred edges, and the degree of necrosis was much higher than that of the experimental group. Anti-snake venom blocking therapy is a new and improved therapy with good clinical effect on local tissue necrosis caused by Chinese cobra bites; moreover, it is superior to conventional chymotrypsin blocking therapy in the treatment of cobra bites. It can better neutralize and prevent the spread of the toxin, reduce tissue necrosis, and shorten the course of the disease by promoting healing of the wound. Furthermore, this treatment plan is also applicable to wound necrosis caused by other snake toxins, such as tissue necrosis caused by elapidae and viper families. This trial is registered in the Chinese Clinical Trial Registry, a primary registry of International Clinical Trial Registry Platform, World Health Organization Registration No. Chinese cobra bites often cause local tissue necrosis and lead to physical disability, which is the difficulty of treatment. Considering that the cytotoxin in cobra is the main pathogenic factor causing local tissue necrosis, we proposed injecting anti-snake venom locally to increase its concentration in the wound, so as to neutralize the cytolytic activity of snake venom. In order to verify the clinical efficacy of the therapy, a randomized controlled trial were conducted: the experimental group was treated with anti-snake venom blocking therapy, while the control group was treated with chymotrypsin blocking therapy. The clinical efficacy was evaluated by comparing the local wound necrosis, wound healing time, etc. as the indicators. Then, the results showed that the experimental group had smaller wound necrosis area and also much shorter healing time than the control group, which clearly indicated that the local blocking treatment with anti-snake venom serum has much better clinical efficacy. Meanwhile, theoretically, the anti-snake venom blocking therapy is also suitable for the treatment against other snake bites. So, in future we expect to conduct more clinical studies on this, which will provide information on new treatments with much better clinical efficacy for patients. Citation: Zeng L, Hou J, Ge C, Li Y, Gao J, Zhang C, et al. PLoS Negl Trop Dis 16 12 : e Editor: Stuart Robert Ainsworth, Liverpool School of Tropical Medicine, UNITED KINGDOM. Received: May 4, ; Accepted: November 29, ; Published: December 16, Copyright: © Zeng et al. This is an open access article distributed under the terms of the Creative Commons Attribution License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability: All relevant data are within the manuscript and its Supporting Information files. Funding: LZ received grants to support this study: Guangdong Medical Research Foundation Grant NO. ZZ and YL received Science and Technology Foundation of Shenzhen City Grant NO. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing interests: The authors have declared that no competing interests exist. Snakebite envenoming was added to the list of neglected tropical diseases in by the World Health Organization [ 1 ], and Chinese cobras are widely distributed around the world, posing a great threat to human safety. Therefore, we must refocus on the treatment and research of snakebites. Chinese cobras, one of the top ten venomous snakes in China are mainly distributed in provinces that are south of the Yangtze River, including Taiwan, Hainan, Hong Kong, and Macao [ 2 ]. The toxins secreted by Chinese cobra include neurotoxins, hematotoxins, and cytotoxins, which are classified according to clinical symptoms [ 3 , 4 ]. Neurotoxins can block neuromuscular conduction, which can lead to muscle paralysis and respiratory failure in severe cases [ 5 , 6 ]. Cobrotoxin is the main neurotoxic protein isolated from the venom of the Chinese cobra Naja atra [ 7 ]. Hematotoxicity destroys the function of the blood system [ 8 ]. The main phospholipase A 2 and its isozymes inhibit blood coagulation by different mechanisms [ 9 , 10 ]. Cytotoxins directly damage skin tissues, manifesting as severe swelling of tissue cells around the necrotic volume, vacuolar degeneration, microvascular embolism [ 4 , 11 ], and other damaging changes, followed by the development of extensive necrosis, with wounds that are often difficult to heal over time, and in severe cases, they cause limb disability or functional impairment [ 12 ]. Cytotoxins have been found to be the main components of Chinese cobra venom, accounting for more than half A variety of cytotoxins analogs have been discovered that act primarily by disrupting the bilayer membrane of cells [ 14 ]. The toxin composition varies by species, with the venom of the Chinese cobra being more abundant in cytotoxins compared to that of Naja kaouthia and Naja siamensis [ 15 ]. Clinical observations have shown that intravenous anti-snake venom treatment is less effective in detoxifying local tissue necrosis caused by cobra bites [ 13 , 16 ]. The main reason may be that after intravenous injection anti-snake venom, it needs to pass through the body via the bloodstream to reach the local wound. As a result, local wounds will retain a high concentrations of toxins [ 17 ], the local tissue continues to ulcerate under the action of cytotoxin. Generally, Chinese cobra bites are associated with disability, and often cause local tissue necrosis [ 18 ]. Therefore, in recent years, new treatments have been proposed to treat local tissue necrosis caused by snake venom. Chymotrypsin EC 3. Generally, cobra cytotoxins is a kind of small three-looped proteins composed of approximately 60 amino acid residues [ 14 ], while chymotrypsin EC 3. Therefore, chymotrypsin has certain degradation effect on snake venom. Furthermore, chymotrypsin which has been used in clinics since , can effectively promote the faster recovery of acute tissue injury by removing necrotic tissue proteins [ 21 ], and is conducive to wound healing. However, chymotrypsin blocking therapy has never solved the problem of wound necrosis caused by snake venom. Considering that cytotoxin is the main pathogenic factor causing local tissue necrosis, neutralization or inactivation of the same is becoming the key to its treatments. Thus, in this study, we proposed to adopt the method of local anti-snake venom injection to strengthen the anti-snake venom effect, which aims to neutralize the cytolytic activity of snake venom through high concentration of anti-snake venom. Thereby, this study sets two treatment schemes: the chymotrypsin blocking treatment scheme and anti-snake venom blocking treatment scheme. Both of them are combination therapies that adopt intravenous injection of anti-snake venom as basic treatment; while their difference is that the local treatment uses either chymotrypsin enzyme control group or anti-snake venom experimental group. The whole therapeutic schedule of this study is shown in the S1 Fig. Here the emphasis is on the fact that the anti-snake venom blocking treatment scheme aims to neutralize the cytolysis of the toxin through intravenous and local injection. Based on this hypothesis, a single-anonymous, parallel groups, randomized controlled trial was designed and conducted to compare the clinical efficacy of these two treatment regimens. This trial was conducted according to the Declaration of Helsinki. Before all the patients were enrolled in the study, the researcher gave full information, which mainly included the purpose and content of the study and the risks and benefits of participating in the study. All the patients received and signed the written informed consent. This study was reviewed and approved by the Ethics Committee of Shenzhen Traditional Chinese Medicine Hospital with approval number K The researcher adopted the EXCEL Microsoft office random number table method to generate the random sequence. To conceal the random sequence for the researchers, an opaque sealed envelope numbered sequentially was shuffled. After the volunteer participants agreed to join and signed the informed consent form, they received the envelope and returned it to the researcher, who assigned the participant to the experimental group or the control group according to the randomization list. This study is a single-anonymous, parallel groups, randomized controlled trial. Shown in Fig 1 , the research selection process was strictly in accordance with the inclusion criteria and exclusion criteria. Chinese cobra Naja atra bite patients enter the screening process after information registration. The study cases were from the emergency department of Shenzhen Traditional Chinese Medicine Hospital from July 9, to July 8, a total of 52 cases met the inclusion criteria, including one with severe diabetes and one with renal insufficiency. Based on the exclusion criteria, two one with severe diabetes and one with renal insufficiency were excluded from the study, and finally 50 cases were included in the randomized grouping. Then according to the ratio, all these cases were divided into the experimental group and the control group. The experimental group was treated with anti-snake venom blocking therapy, while the control group was treated with chymotrypsin blocking therapy. Finally, the patients were followed up until the wound healed, and the efficacy was evaluated. According to the Chinese Expert Consensus on Snakebite Treatment [ 22 ] and the relevant content of the diagnosis and treatment protocol of Shenzhen Traditional Chinese Medicine Hospital, the cobra bite cases were diagnosed and confirmed based on the following criteria:. The sample size was estimated according to the main efficacy evaluation indicators, and the necrosis volume of the snake bite wound mm 3 is set as the main efficacy evaluation indicator. Referring to the relevant literature and previous clinical observations, it is found to be significant when the necrosis volume of difference between the wound and healthy volume is up to at least 23 within the same sample size. The researchers who administered the treatment were not anonymized, but the patients and the measurers were, and the researchers who implemented the closed therapy were separated from the outcome measurers to reduce bias and ensure that the results of the experiment were objective and true. All participants who passed the screening and entered the trial, were considered as dropout cases if they were not able to complete the observation specified in the protocol regardless of when and why they withdrew. In the course of the trial, once serious adverse events occur, the trial would be immediately terminated and treated as case dropout. For those who quit the trial midway, take active measures to record the last test result as far as possible. According to the routine treatment plan of the Shenzhen Traditional Chinese Medicine Hospital, Department of Snakebite, the procedure which is shown in S1 Fig was performed as follows [ 23 ]:. The necrotic volume of the wound is the main therapeutic evaluation index. So, the volume of wound necrosis before closure treatment was measured on the third and seventh days post-treatment. This study set up had measurement specialists and used uniform measurement standards and anonymized measurements measurement specialists could not obtain patient enrollment information. The three-dimensional volume was measured after debridement and removal of the necrotic tissue: length×width×depth to calculate the measurement of the pressure sore volume. Additionally, the width was measured along the direction perpendicular to the long axis. The depth was measured along the direction perpendicular to the body surface; the widest and longest part of the surface and the deepest depth were measured with the head as the coordinates, the length in the longitudinal direction, the width in the transverse direction, and the depth perpendicular to the body surface. If the wound was irregular, it was measured and predicted with care. After the third day of the treatment, the wound tissues of these two groups were randomly selected for pathological section detection to further evaluate the severity of local tissue necrosis of the wounds. The testing institution was Department of Pathology in Shenzhen Traditional Chinese Medicine Hospital. The tooth mark left by the snake bite was then taken to the center, where 2 mm 3 tissue was cut from the edge of the tooth mark with a sterile surgical blade and sent to the Department of Pathology for determination. SPSS The measurement data such as age, height, weight, body mass index, time between bite and treatment, snake bite severity score, wound necrosis volume, and wound healing time, were described by the mean ± SD. Moreover, the data conforms to the homogeneity of variance and normal distribution, T-test was adopted for these data analysis. While Sender, Bite site case , Length distribution of cobras case belongs to count data, and the χ2 test was employed for them. Among the 50 patients, 47 were male and 3 were female. No case dropped out during the study. The youngest and oldest participants were 19 years and 60 years old, respectively. Height ranged from cm to cm, weight ranged from 50 kg to 76 kg, and BMI ranged from 19 to The sites of snakebite envenoming were distributed in the limbs: 22 cases of upper limbs and 28 cases of lower limbs. The shortest period from a venomous snakebite to hospital admission was 10 minutes and the longest was 2 hours. The length range of venomous snakes was from 0 to 3 meters. According to the snakebite severity scale in the Chinese Expert Consensus on Snakebite Treatment [ 23 ], at admission, the lowest score was 2 points, and the highest score was 7 points, with an average score of 3. Throughout the study, two patients developed a reaction to the intravenous anti-snake venom, mainly manifested as a sparse rash throughout the body. This procedure ensured that the treatment was not interrupted due to reactions. From the data shown in Table 3 , there was no significant difference in the wound volume between the two groups on the first day of treatment. However, on the third day, the necrotic volume of the wound peaked in both groups. Moreover, the control group Following this, the necrotic volume of the two groups gradually narrowed. It can be inferred that the treatment plan for the experimental group was superior to that of the control group since it could more effectively reduce the necrotic volume of the wound. This indicates that the treatment plan of the experimental group Pictures of bites at the same site from the two groups of patients were randomly selected for comparison; the two figures above Fig 3A and 3B show the state of the wound after cleaning, without any surgical intervention. Fig 3A shows the wound surface on the third day of treatment of the control group with the Area A as small thrombus and Area B as necrotic adipose tissue. Meanwhile, Fig 3B shows the wound surface on the third day of treatment of the experimental group with Area C as necrotic adipose tissue. We found that the necrotic volume of the wound of the control group was significantly larger than that of the experimental group. The wound surface on the third day of treatment in the control group; A shows small thrombus and B shows necrotic adipose tissue. C shows necrotic adipose tissue. Fig 3B. The wound surface on the third day of treatment in the experimental group; C shows necrotic adipose tissue.