Effect of isolation protocols and cryoprotectants on freezing of stallion epididymal spermatozoa.

BACKGROUND: The recovery of spermatozoa from the cauda epididymis may be the only option to obtain genetic material from elite stallions that had undergone castration or sudden death due to colic or severe injury. OBJECTIVE: To evaluate two different protocols for retrieval of stallion epididymal spermatozoa and to evaluate different cryoprotectants on the freezability of the epididymal spermatozoa. MATERIALS AND METHODS: Six epididymides from three stallions were collected immediately after routine castration under general anesthesia. In the first experiment, each epididymis (of two testes) of the same stallion were processed using different methods for retrieval of the epididymal spermatozoa and were pooled and cryopreserved either using 5% glycerol or 5% dimethyl formamide (DMF) as cryoprotectant. The semen quality parameters viz., progressive motility, HOST, viability and acrosome integrity were evaluated at the fresh, pre-freeze and post-thaw stages. RESULTS: Retrograde method of flushing of epididymis yielded significantly (p < 0.05) higher concentration of the stallion sperm than that of the floating method. The qualitative semen parameters i.e., viability, plasma membrane integrity and acrosome integrity were found to be significantly restored using 5% DMF as cryoprotectant in comparison to when 5% glycerol was used. CONCLUSION: Retrograde flushing method of epididymis yielded significantly higher sperm concentration to that of the floating method, and 5% DMF as cryoprotectant provided acceptable freezability of stallion epididymal spermatozoa. DOI: 10.54680/fr23310110312.

Uncovering the structure and function of specialist bacterial lineages in environments routinely exposed to explosives.

Environmental contamination by hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), the two most widely used compounds for military operations, is a long-standing problem at the manufacturing and decommissioning plants. Since explosives contamination has previously been shown to favour the growth of specific bacterial communities, the present study attempts to identify the specialist bacterial communities and their potential functional and metabolic roles by using amplicon targeted and whole-metagenome sequencing approaches in samples collected from two distinct explosives manufacturing sites. We hypothesize that the community structure and functional attributes of bacterial population are substantially altered by the concentration of explosives and physicochemical conditions. The results highlight the predominance of Planctomycetes in contrast to previous reports from similar habitats. The detailed phylogenetic analysis revealed the presence of operational taxonomic units related to bacterial members known for their explosives degradation. Further, the functional and metabolic analyses highlighted the abundance of putative genes and unidentified taxa possibly associated with xenobiotic biodegradation. Our findings suggest that microbial species capable of utilizing explosives as a carbon, energy or electron source are favoured by certain selective pressures based on the prevailing physicochemical and geographical conditions.

Acute renal failure following poisonous snakebite.

This study describes acute renal failure (ARF) following snakebite in humans and the effects of viperide venoms on the renal structure and function in subhuman primates. ARF developed in 45 of 157 patients with a history of snakebite admitted to the hospitals of the Postgraduate Medical Institute, Chandigarh, India. They were studied clinically, hematologically, and in 35 cases, for renal histopathology. All 45 were treated with antibiotics, and 8 received anti-snake venom. Ten cases had bilateral renal cortical necrosis (BRCN), eight of whom died; less severe acute tubular lesions (ATL) occurred in 23 patients, four of whom died (P less than .001). Sepsis was significantly more common with BRCN than ATL (P less than .05). No statistical difference was found between these groups in bleeding incidence, disseminated intravascular coagulation (DIC), hemolysis, or hypotension. Monkeys given lethal doses of viperide venom developed hypotensive shock, DIC, and hemolysis, with significantly reduced serum complement, and died within 24 hours. However, no renal functional changes or lesions were found. Monkeys given sublethal doses of viperide venom showed a significant increase in serum creatinine levels after 48 hours, and renal lesions were observed in a majority of animals. In conclusion, ARF in snakebite victims appears to be multifactorial in origin. Although hypotension, hemolysis, and DIC are likely to be important pathogenetic factors, a direct cytotoxic effect of the venom on the kidney in producing ARF cannot be excluded.

Hemostatic abnormalities following Echis carinatus (saw-scaled viper) envenomation in the rhesus monkey.

Hemostatic abnormalities following lethal and sublethal doses of Echis carinatus venom were studied in a subhuman primate model. The observations suggest the occurrence of disseminated intravascular coagulation of varying magnitude within a few hours of envenomation. A procoagulant effect of the venom of Echis carinatus is likely to be the major cause of the disturbance in the hemostatic mechanism.

Coagulation abnormalities induced by Russell's viper venom in the rhesus monkey.

Coagulation studies were carried out in a group of non-human primates (rhesus monkeys) following envenomation with lethal and sublethal doses of Russell's viper venom. The envenomated animals showed significant fibrinogenopenia in association with or without disseminated intravascular coagulation. The findings offer a rational explanation for the bleeding manifestations seen in clinical cases of Russell's viper bite.

Complement depletion following envenomation by Russell's viper and Echis carinatus (saw-scaled viper) in the rhesus monkey.

Significant depletion of C3 was observed following administration of lethal and sublethal doses of Russell's viper and Echis carinatus venom to rhesus monkeys. A sequential study carried out over a period of 3 weeks following sublethal envenomation showed a steady rise in the C3 level from 48 hours onwards. By the 20th day the C3 values had attained the pre-envenomation levels. The extent of depletion of C3 was similar in both Russell's viper and E. carinatus envenomation. Because of the close immunological similarity of monkey and man, the rise in C3 which corresponded with recovery of the animals in this experimental model could serve as a useful parameter of recovery in clinical cases of snake poisoning.

Acute renal failure due to intravascular hemolysis in the North Indian patients.

Acute renal failure due to intravascular hemolysis is a common clinical problem in North Indian patients. It constituted 21.5 percent of 325 patients dialyzed for acute renal failure over an 11-year period at Chandigarh. Thirty patients had developed acute intravascular hemolysis in association with erythrocyte glucose-6 phosphate dehydrogenase (G-6PD) deficiency, 17 due to copper sulphate intoxication and 8 due to envenomation by snakes. Less frequent causes were insect stings, incompatible blood transfusion, intake of anti-leprosy drug--dapsone in non-G-6PD-deficient patients, and mercuric chloride toxicity in two patients each; naphthalene poisoning in one; and uncertain causes in six patients. Renal histology was available in 55 patients. Acute tubular necrosis was seen in 54 and bilateral diffuse cortical necrosis in one patient. Fifty patients (71.43 percent) survived and 20(28.6 percent) diet. G-6PD erythrocyte deficiency, which is present in 4.5 percent of the North Indian population, was the most frequent cause of acute renal failure in this group.

Acute renal failure of obstetric origin.

Acute renal failure of obstetric origin is common among North Indian patients and comprised 72 (22.1%) of 325 patients undergoing dialysis over an 11-year period. Of these, 46 gravidas had developed renal failure following abortion, and 29 cases were due to complications of late pregnancy. The most striking feature of this study was a high incidence of irreversible renal lesions of bilateral diffuse cortical necrosis in early (18.6%) as well as late pregnancy (37.8%). Overall incidence of diffuse cortical necrosis was 25%. In the remainder, acute tubular necrosis was seen in 52 (72.2%), patchy cortical necrosis in 1 (1.4%), and tubular necrosis along with glomerular involvement in 1 patient (1.4%). Pathogenetic factors which contributed to the development of renal failure, either singly or in combination, were loss of blood failure, either singly or in combination, were loss of blood (79.1%), septicemia (31.9%), hypotension due th hemorrhagic and septicemic shock (51.4%), eclamptic toxemia (11.1%), and disseminated intravascular coagulation in 12.5% patients. Infrequent occurrence of disseminated intravascular coagulation in the septic anc eclamptic patients who developed diffuse cortical necrosis was an interesting finding, as was the fact that coagulopathy was more frequently observed in acute tubular necrosis. Late referral, frequent sepsis, and high incidence of bilateral diffuse cortical necrosis contributed significantly to a high mortality (55.3%).