42 research outputs found
Repurposing cancer drugs, batimastat and marimastat, to inhibit the activity of a group I metalloprotease from the venom of the Western Diamondback rattlesnake, Crotalus atrox
Snakebite envenomation causes over 140,000 deaths every year predominantly in developing countries. As a result, it is one of the most lethal neglected tropical diseases. It is associated with an incredibly complex pathophysiology due to the vast number of unique toxins/proteins found in the venoms of diverse snake species found worldwide. Here, we report the purification and functional characteristics of a group I metalloprotease (CAMP-2) from the venom of the western diamondback rattlesnake, Crotalus atrox. Its sensitivity to matrix metalloprotease inhibitors (batimastat and marimastat) was established using specific in vitro experiments and in silico molecular docking analysis. CAMP-2 shows high sequence homology to atroxase from the venom of Crotalus atrox and exhibits collagenolytic, fibrinogenolytic and mild haemolytic activities. It exerts a mild inhibitory effect on agonist-induced platelet aggregation in the absence of plasma proteins. Its collagenolytic activity was completely inhibited by batimastat and marimastat. Zinc chloride also inhibits the collagenolytic activity of CAMP-2 by around 75% at 50 M, while it is partially potentiated by calcium chloride. Molecular docking studies demonstrate that batimastat and marimastat are able to bind strongly to the active site residues of CAMP-2. This study demonstrates the impact of matrix metalloprotease inhibitors in the modulation of a purified, group I metalloprotease activities in comparison to the whole venom. By improving our understanding of snake venom metalloproteases and their sensitivity to small molecule inhibitors, we can begin to develop novel and improved treatment strategies for snakebites
Dynamic Mechanical Analysis of Bio-Based and Synthetic Petroleum Based Polymer Foams with Powder Type Organic Filler at Prolonged Ultra-Violet Exposure
Wood powder filler that have been added in the bio-based and epoxy polymer foams can be proved that it have ability to strengthen the structure of polymer foams. In this study, ‘Meranti’ type wood filler has been used as the filler. This study was developed to observe the pore size of each sample when expose to different hours of UV irradiation exposure using Optical Microscopy (OM). This study was also to compare the mechanical properties of every sample with different ratio filler of 0 wt%, 5 wt%, 10 wt%, 15wt% and 20 wt% at different hours of UV irradiation exposure which is 0 hour until 6,000 hours with increment of 2,000 hours. The testing was run by DMA Q800 TA machine. The samples that have 40 x 10 x 5 mm size were clamped in the machine to get the result of their mechanical properties. From the DMA testing, the results will show the value of tan delta, loss modulus and storage modulus. The value of tan delta shows that higher ratio filler will give the high value of tan delta. The epoxy polymer foams with powder filler have the highest value of tan delta compare to bio-based polymer foams. It proves that the higher filler ratio, the lower value of tan delta can be recorded. The result of storage and loss modulus was found to increase as the more filler ratio filler in the polymer foams. The higher the loss modulus and storage modulus, the lower the temperature. Bio-based polymer foams with high powder filler ratio can dissipate more energy as energy are lost as heat during UV irradiation exposure
Dynamic Mechanical Analysis of Synthetic epoxy (E) and Bio-epoxy Polymer Foam Integrated with Wood Filler Under 8000 hours Exposure to UV Irradiation
The most common sustainable solution for polyurethane (PU) materials is their production using renewable resources reducing the dependency on the consumption of petroleum-based oil products. This research presents results from an experimental study on the dynamic mechanical and viscoelastic properties such as storage modulus, E', loss modulus, E'' and damping coefficient, tan δ of syntactic epoxy (E) and bio-epoxy polymer foam loading with different ratio of flakes and powder filler 0, 5, 10, 15 and 20 %wt after exposed to UV irradiation for 8000 h. Dynamic mechanical analysis (DMA) of the blended were performed over a temperature range of 25–180°C for (E) and (B) polymer foam under frequency of 1 Hz. The results demonstrated that the E20L specimen with the highest filler ratio gives the maximum storage modulus and loss modulus value (0.3125 MPa), (0.0625 MPa) respectively among other filler ratio due to bonding between foam and filler resulting in increased viscosity of the synthetic-epoxy PUs foam. Among others, the bio-epoxy PUs foam (B5P) has the highest storage value (3.956 MPa) and loss modulus (17.213 MPa) indicating that bio-epoxy PU foams can dissipate energy faster than synthetic-epoxy polymer foams. TG analysis showed that the synthetic epoxy (E) polymer foam had higher Tg value and E5L (1.2) archived the highest value compared to the bio-epoxy foams which had much less repeatable results due to the less homogeneous structure of polyols.compulsory
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Russell's viper envenomation induces rectus sheath haematoma
Snakebite envenomation causes systemic and local manifestations, which result from the individual or synergistic actions of multiple venom components. The pathological hallmarks of medically important venomous snakes such as the Indian Russell's viper (Daboia russelii) are well known. Envenomation by Russell’s viper is typically characterised by coagulopathies, muscular damage, nephrotoxicity, and neurotoxicity. However, recent reports have revealed several unusual complications that provide a better understanding of Russell’s viper envenomation effects. To further strengthen this, here, we report a case of Russell's viper bite that induced acute abdominal pain, which was intensified on day two and conservatively treated under medical supervision. Both Fothergill and Carnett signs were positive for this patient. An ultrasound imaging revealed a dissimilar dense mass, and the abdominal computed tomography scan confirmed rectus sheath haematoma. The clinical management involved the administration of polyvalent antivenom, packed red blood cells, fresh frozen plasma, and platelets. The patient recovered gradually and was discharged from the hospital eight days after the bite. Overall, this case presentation shares an uncommon experience and adds new insights into the complex series of rare pathological events associated with Russell's viper bites in India. The scientific documentation of relatively infrequent entities based on an ongoing living assessment of medical experiences, for example, this rectus sheath haematoma, constitutes valuable guidance for an adequate diagnosis and timely treatment. Essential awareness among clinicians and further research on understanding the molecular relationship between Russell’s viper venom and rectus sheath haematoma will improve patient outcomes and understanding of this condition, respectively
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Novel strategies to mitigate snakebite burden in India
Snakebite envenoming (SBE) is a neglected tropical disease affecting the rural impoverished
communities in many tropical and subtropical countries. Around 5.4 million people are affected by
snakebites each year resulting in around 1.8-2.7 million cases of envenoming, 140,000 deaths and triple
the number of amputations and permanent disabilities. India is considered the 'snakebite capital' of the
world and it is estimated to account for up to 50% of these snakebite statistics. Unfortunately, accurate
epidemiological field data on SBE like most other neglected tropical diseases is lacking, and often
remains incomplete; this can be attributed to multiple reasons such as a lack of policy, inadequate
funding to conduct the research, limited medical and health infrastructure for data collection and
monitoring and difficulties in ascertaining reporting data in rural areas to measure the true impact of
SBE. Delays in seeking prompt hospital treatment are one of the primary causes of SBE-induced deaths
and disabilities. The root causes for patients to defer and postpone hospital treatment are many and
complex, from strong confidence in traditional healers for treating SBE to fear of high treatment costs
in hospitals. The clinical presentation following SBE of many snake species across India can be quite
different, but there are no defined diagnostic tests or biomarkers available to aid prompt diagnosis of
SBE specifically in rural healthcare settings. Notably, healthcare professionals in rural settings often
lack confidence and training in managing SBE. Hence, in the first theme of this study, we sought to
develop the use of novel biomarkers such as neutrophil gelatinase-associated lipocalin (NGAL) in
Russell’s viper bites, determine the most effective yet affordable antibiotics for SBE, evaluate the
treatment costs for SBE in private tertiary care hospitals and establish knowledge gaps and training
needs for healthcare professionals to pinpoint areas of focus to improve the clinical management of
SBE in India. In the second theme of this study, we aimed to determine the level of snake phobia in
Indian communities, understand the challenges faced by snake rescuers who play a vital role in
mitigating SBE burden while saving lives, and the necessity to improve public awareness about SBE.
Overall, this study has underpinned various aspects of SBE, and these findings will form a strong base
to develop several health policies to mitigate the SBE burden in rural India
PROCESSIBILITY OF WASTE TO WEALTH GREEN POLYMER WITH POLYETHYLENE BY INJECTION MOULDING
Green polymer from waste cooking oils is successfully converted into high functionality of hydroxylated green monomer. The green monomer was used crosslinker and known as Green Polymer. Green Polymer is compounded with High-Density Polyethylene (HDPE) and Low-Density Polyethylene (LDPE). These wastes to wealth green polymer are successfully compounded with HDPE and LDPE by melt-mixing used an injection molding machine known as Pro-GreP. The effect of different ratio of compounding materials on the mechanical properties of Pro-GreP was studied by tensile test. Morphological of surface fracture with magnification 100x on Pro-GreP is revealed the homogenous characteristic with high compatibility properties. Finally, the presence of biopolymer provide biodegradable properties, but it also improves the mechanical properties. It can be showed that the tensile strength and tensile strain is decreased than the neat thermoplastic and they were found to decreased with the increasing of biopolymer compounds. However, LDPE are lower in tensile strength and tensile strain than HDPE.</jats:p
Renewable Polymer/ Thermoplastics Polyethylene Blended with Enhanced Mechanical and UV Stability Properties
Blends of Renewable Polymer (RP) and thermoplastic polyethylene (LDPE and HDPE) may contribute to make recycling more economically attractive. In this study, the monomer is mixed with flexible isocynate as a crosslinker, these mixture is called Renewable Polymer. Renewable polymers are mixed in a Low-density polyethylene (LDPE) and High-density polyethylene (HDPE) with a ratio of 5%, 10%, 15%, 20%, 25% and 30%. The aim of this work to make LDPE/RP and HDPE/RP blends injected via injection molding and to evaluate their mechanical properties via tensile test. Accelerated weathering test up for 500 hours, 1000 hours, 1500 hours, 2000 hours, 2500 hours and 3000 hours. The blends yielded tensile strength and maximum elongation at break curves very dependent on their composition, especially regarding the presence of necking. The tensile strength increase at 500 hours, while maximum elongation at break were found to decreased with increase of UV irradiation hours. In conclusion, RP content and UV irradiation time play significant roles in controlling mechanical properties of the RP-blended with LDPE and HDPE synthetic polymer, thus providing the opportunity to modulate polymer properties
Mechanical Properties of Renewable Polymer with Thermoplastics Endurance to Ultraviolet irradiation Exposure
At present the disposal of waste tyre rubber (WTR) has become a major waste management problem in the world. Therefore in this study, polymer blended based on Polyethylene which is Low Density Polyethylene (LDPE) or High Density Polyethylene (HDPE), with Renewable Polymer (RP) and waste tyre rubber (WTR) is prepared via injection molding. Blended polymer such as LDPE/RP/WTR and HDPE/RP/WTR is known as LRT and HRT respectively. The preparation of polymer blend steps start with the preparation of RP. The RP is prepared by crosslinking the renewable monomer with Polymethane Polyphenyl Isocyanate (MDI) at composition ratio of 1:0.5. The second steps involved by adding 10 gm of liquid RP prepared earlier on with fixed amount of LDPE and HDPE of 100 gm. Then the blended LDPE/RP or HDPE/RP namely as LR or HR respectively is further added with WTR with different percentages ratio of 5 %, 10 % and 15 %. The manually blended polymer mixture and filler is then melt mixing using injection moulding to fabricate the tensile specimen for mechanical tensile test and physical determination such as density, distribution of WTR in polymer blend and surface fracture morphology using scanning electron microscope. The samples were then exposed to UV irradiation exposure in UV Accelerated Weathering for 500, 1000, 1500, 2000, 2500 and 3000 hours to evaluate the photostability of the polymer blends. The optimum amount of WTR ratio composition is at 5 % for both LRT and HRT blends which indicate the stability of polymer blends towards UV irradiation exposure at 1000 hours
Mechanical Properties of Renewable Polymer with Thermoplastics Endurance to Ultraviolet irradiation Exposure
At present the disposal of waste tyre rubber (WTR) has become a major waste management problem in the world. Therefore in this study, polymer blended based on Polyethylene which is Low Density Polyethylene (LDPE) or High Density Polyethylene (HDPE), with Renewable Polymer (RP) and waste tyre rubber (WTR) is prepared via injection molding. Blended polymer such as LDPE/RP/WTR and HDPE/RP/WTR is known as LRT and HRT respectively. The preparation of polymer blend steps start with the preparation of RP. The RP is prepared by crosslinking the renewable monomer with Polymethane Polyphenyl Isocyanate (MDI) at composition ratio of 1:0.5. The second steps involved by adding 10 gm of liquid RP prepared earlier on with fixed amount of LDPE and HDPE of 100 gm. Then the blended LDPE/RP or HDPE/RP namely as LR or HR respectively is further added with WTR with different percentages ratio of 5 %, 10 % and 15 %. The manually blended polymer mixture and filler is then melt mixing using injection moulding to fabricate the tensile specimen for mechanical tensile test and physical determination such as density, distribution of WTR in polymer blend and surface fracture morphology using scanning electron microscope. The samples were then exposed to UV irradiation exposure in UV Accelerated Weathering for 500, 1000, 1500, 2000, 2500 and 3000 hours to evaluate the photostability of the polymer blends. The optimum amount of WTR ratio composition is at 5 % for both LRT and HRT blends which indicate the stability of polymer blends towards UV irradiation exposure at 1000 hours
