Biomedical subjects

R E Phillips

Publications and source records attributed to R E Phillips.

185 records · Page 11Linked to original sources

PubMedDate not supplied

Bacteriological studies of the venom and mouth cavities of wild Malayan pit vipers (Calloselasma rhodostoma) in southern Thailand.

Venom and oropharyngeal swabs from freshly captured Malayan pit vipers (Calloselasma rhodostoma) in southern Thailand and captive specimens in England were cultured aerobically and anaerobically to identify the bacterial flora which might contaminate wounds inflicted by bites of this species. The snakes' mouths contained a wider range of organisms than their venoms, especially gut-related Gram-negative rods such as Enterobacter and Pseudomonas species and some staphylococci and clostridia. There were fewer positive cultures from captive snakes. C. rhodostoma venom inhibited the growth of group A streptococci and, to a lesser extent, that of Staphylococcus aureus and Clostridium perfringens but not that of 2 Gram-negative organisms. Secondary bacterial infection is an important complication of snake bite, especially of necrotic wounds. A combination of gentamicin with benzyl penicillin would have prevented infection with, or treated, most of the bacteria isolated from snake venoms and mouths in Thailand.

Animals↗

PubMedDate not supplied

Envenoming by the common krait (Bungarus caeruleus) and Sri Lankan cobra (Naja naja naja): efficacy and complications of therapy with Haffkine antivenom.

In Anuradhapura, Sri Lanka, 5 patients proved to have been bitten by common kraits (Bungarus caeruelus) and 2 by Sri Lankan cobras (Naja naja naja) were investigated. In all the cases of krait bite the patients were bitten while they were asleep: local signs were negligible but 4 developed symptoms of systemic envenoming including paralysis, muscle pain and tenderness and abdominal pain. Mild myoglobinaemia was found in one case. Of the 2 patients bitten by cobras, one developed severe local swelling which progressed to necrosis and the other local swelling and respiratory paralysis. Response to polyspecific antivenom (Haffkine, India) was neither rapid nor convincing. Venom antigenaemia became undetectable within 2 h of the start of antivenom treatment, but recurred 25 and 65 h later in 2 cases. Among a group of 27 patients treated with this antivenom (including 21 bitten by Russell's vipers), the incidence of early anaphylactic and pyrogenic reactions was high at 52% and 65% respectively. Anticholinesterase did not improve paralysis in 2 patients bitten by kraits. The respiratory failure in 2 patients was successfully treated by mechanical ventilation for 8 and 30 h. These observations confirm the importance of neurotoxic symptoms following bites by these species but also suggest a contributory role of generalized rhabdomyolysis in krait victims and emphasize the problem of severe local tissue necrosis in cobra victims. There is a need for safer and more potent antivenoms for use in Sri Lanka.

Adult↗

PubMedDate not supplied

Development of renal function abnormalities following bites by Russell's vipers (Daboia russelii siamensis) in Myanmar.

Renal function was monitored in 24 patients with systemic envenoming following proven Russell's viper bite. In all patients, blood clotted within 20 min on admission. In 15 cases severe defibrination (systemic envenoming) developed during the next 3-5 d. None of the patients received antivenom before admission but enzyme-refined monospecific antivenom was given to those who developed signs of systemic envenoming. Specific antigen was detected by enzyme immuno-assay in all 21 subjects tested. Nine patients whose renal function remained normal did not develop systemic envenoming, and recovered without any treatment even though venom antigen was detectable in their serum. Ten patients developed mild renal dysfunction and systemic envenoming, but recovered after treatment with antivenom alone. The remaining 5 patients, all of whom were oliguric from admission, developed acute renal failure despite treatment with antivenom, but some recovered after peritoneal dialysis. Serum venom antigen levels were high in the last 2 groups, but there was some overlap. Albuminuria, found only in patients who became systemically envenomed, was associated with high fractional sodium excretion in those who developed acute oliguric renal failure. Albuminuria may appear before a gross clotting defect is detectable. It is an indication for antivenom and spot measurements might prove a useful early predictor of outcome.

Acute Kidney Injury↗

PubMedDate not supplied

Renal ischaemia, transient glomerular leak and acute renal tubular damage in patients envenomed by Russell's vipers (Daboia russelii siamensis) in Myanmar.

Fifty-two patients who had been bitten by Russell's vipers in Myanmar developed acute renal failure (serum creatinine exceeding 1.3 mg/dL). Thirty-four of them (65%) became oliguric, but the other 18 (35%) maintained a urine output of more than 400 mL/24 h. In oliguric patients, gastrointestinal haemorrhages, renal angle tenderness and conjunctival oedema occurred more commonly, and peak serum creatinine, blood urea nitrogen and the fractional excretion of sodium were significantly higher (P < 0.01) than in non-oliguric patients, indicating a greater degree of renal damage. Urinary concentrations of beta 2 microglobulin and retinol binding protein were raised in most of the patients indicating failure of proximal tubular reabsorption of these proteins, while high urinary N-acetyl glucosaminidase concentrations were consistent with renal tubular damage. Plasma concentrations of active renin were very high, suggesting that renal ischaemia, associated with activation of the renin-angiotensin system, was involved in the development of renal dysfunction.

Acute Kidney Injury↗

PubMedDate not supplied

Nonaldehyde sterilization of biologic tissue for use in implantable medical devices.

Biologic tissue stabilized by dye-mediated photooxidation has found application in implantable devices. The desire to avoid aldehydes in the processing of photooxidized tissues led to the development of a nonaldehyde, iodine based sterilant. The interaction of tissue with iodine was indicated by a change in tissue shrinkage temperature, dependent upon solution and incubation parameters. The amino acid tyrosine also was altered, presumably because of aromatic ring iodination. Transmission electron microscopic study indicated no change in the quarter staggered array structure of collagen under controlled iodine treatment conditions. The D10 values for iodine kill of several organisms, in the absence of tissue, were determined in 0.1% iodine (pH 6.5) at 37 degrees C for Bacillus subtilis (12 min, Aspergillus niger, Escherichia coli, Candida albicans, Staphylococcus aureus, and Pseudomonas aeruginosa (all < 1 min). In a separate experiment, samples of 0.1% iodine (pH 6.5) containing photooxidized pericardial tissue were inoculated with 1.6 X 10(7) Bacillus subtilis, 4.6 X 10(6) Pseudomonas aeruginosa, or 7.2 X 10(6) Staphylococcus aureus and incubated at 37 degrees C. No survivors were detected on the tissue samples after exposure of 48 hr. Photooxidized pericardial tissue samples inoculated with either 3.2 X 10(5) porcine parvovirus or 1 X 10(9) infectious bovine rhinotracheitis were exposed to 0.1% iodine (pH 6.5) at 36 degrees C for 12 h. No viral particles were detected after exposure, yielding minimum viral log reduction factors of 3.0 and 6.5, respectively. The results presented indicate the potential for the nonaldehyde, iodine based solution to sterilize implantable devices containing biologic tissue.

Amino Acids↗