Search PubMed⌕ Search

Biomedical subjects

R Edwards

Publications and source records attributed to R Edwards.

At least 307 records · Page 17Linked to original sources
PubMed1986

Comparative toxicity of cis-cypermethrin in rainbow trout, frog, mouse, and quail.

The synthetic alpha-cyano-phenoxybenzyl-containing pyrethroid insecticides act on the CNS of vertebrates and show a species-selective toxicity in the order fish greater than amphibians much greater than mammals greater than birds. Concentrations of [14C]cis-cypermethrin in the brains of representative members of each of these classes of chordates were measured at toxic signs (an onset of hyperactivity followed by seizures and loss of balance/equilibrium) as an indicator of target organ sensitivity. The concentration of cis-cypermethrin in brain, associated with toxic signs, in micrograms per gram (mean +/- SE) as determined by high-performance liquid chromatography was 0.08 +/- 0.03 (frog), 0.23 +/- 0.05 (trout), 1.71 +/- 0.33 (mouse), and 3.94 +/- 0.88 (quail). Trout brain was equally sensitive to the cis and trans isomers of cypermethrin. In both mouse and quail, some 90% of the radioactivity in the brain was parent pyrethroid. Trout and frog, however, afforded only 56 and 32%, respectively, of the brain 14C as cypermethrin, with the remaining radioactivity in both extractable and nonextractable metabolites, including 4'-hydroxy-cis-cypermethrin, which is potentially neuroactive. Following oral administration, cis-cypermethrin was readily absorbed and metabolized by quail. Intestinal uptake was far less rapid in trout and mouse, with unchanged cypermethrin dispersed in secreted bile, being readily eliminated from the intestines of fish. The uptake and metabolism of cis-cypermethrin and the brain sensitivities of these animals to the pyrethroid account for the observed differences in acute toxicity.

Animals↗
PubMed1986

Cytogenetic analysis of adult acute lymphoblastic leukemia including a Ph+ case surviving more than 5 years.

We have performed cytogenetic analysis on 25 consecutive adult patients with previously untreated acute lymphoblastic leukemia (ALL) who were subsequently treated with the same protocol at this institution. Ten of the 25 patients studied (40%) demonstrated karyotypic abnormalities. The most frequent abnormalities were hyperdiploidy (six patients) and presence of the Philadelphia (Ph) chromosome (three patients). Univariate analysis of 12 features identified only immunophenotype as differing between patients with abnormal and normal karyotype. The cells of patients with an abnormal karyotype were more often non-B, non-T and less often T cell in phenotype. One patient initially with Ph remains cytogenetically normal in complete remission 272 weeks post diagnosis. We confirm that cytogenetic abnormalities are frequent in adult ALL. The attainment of disease free survival in Ph-positive ALL of more than 5 years with persistently normal cytogenetics demonstrates that aggressive multimodal therapy can induce long-term remissions and possible cure of this usually unfavorable situation.

Adolescent↗
PubMed1986

Characterisation and antibiotic susceptibilities of Streptobacillus moniliformis.

The characteristics of seven strains of Streptobacillus moniliformis, including four isolates from a recent outbreak of Haverhill fever, are reported. Acid production from carbohydrates was uniform apart from variable reactions with mannose and salicin. Enzymatic reactions determined by the API ZYM system and fatty-acid profiles were generally consistent and may be of value in the rapid identification of S. moniliformis. Penicillin was the most active of the antibiotics tested in vitro, which supports its use as the drug of choice in the treatment of Haverhill fever.

Acids↗
PubMed1985

In vitro fertilization: a treatment for male infertility.

Three-quarters of 41 women whose husbands were the cause of infertility in the couple had one or more embryos replaced after in vitro fertilization. One-third became pregnant despite their long history of infertility; the incidence of pregnancy was 45% after one or more replacements of embryos. In a group of 61 couples where both partners were infertile, 26% became pregnant. These data indicate that the lower chance of fertilization with poor semen is balanced by a higher chance of pregnancy in women with a normally functioning reproductive system. Oligospermia, asthenospermia, teratospermia, and autoimmunity are among the many forms of male infertility which can now be successfully treated by in vitro fertilization. Overall, 57% of the oocytes were fertilized, and almost 50% of men with very low numbers of active spermatozoa (less than or equal to 0.5 X 10(6)/ml motile spermatozoa) were successful in establishing pregnancy. Two semen parameters impaired fertilization most: seminal inflammatory cells and low progressive activity. The collection of split ejaculates and the careful preparation of spermatozoa, by sedimentation and layering methods, proved to be beneficial, improving sperm motility and raising the chance of fertilization.

Embryo Transfer↗
PubMed1985

Laboratory studies on coagulase-negative staphylococci from CAPD-associated peritonitis.

This study compared the static and kinetic activities, in both broth and used-dialysate, of selected antibiotics against 23 strains of coagulase-negative staphylococci causing peritonitis in patients on continuous ambulatory peritoneal dialysis (CAPD). Vancomycin was shown to be effective against all isolates with similar rates of kill to flucloxacillin and cefuroxime, although a few strains were found to be resistant to cefuroxime. Gentamicin was rapidly bactericidal for sensitive strains which accounted for 60% of the strains tested. Fusidic acid was associated with significant resistance and lack of bactericidal activity in the kinetic studies. Emergence of resistance occurred with rifampicin. The combinations clavulanic acid/amoxycillin and sulbactam/ampicillin generally showed good static activity. In addition a broad range of biotypes and phage types were demonstrated among these organisms with biotype SII (Staphylococcus epidermidis) predominating. There was no correlation between biotype and antibiogram.

Anti-Bacterial Agents↗
PubMed1985

A microbiological study of diabetic foot lesions.

The bacterial nature of infected foot lesions presenting to a diabetic unit during the course of twelve months was studied. Fifty-six swabs were obtained from 25 patients. Swabs were processed within ten minutes of being collected. An average of 3.3 organisms per swab were isolated, Staphylococcus aureus was the most common bacterial species isolated, while anaerobic bacteria comprised 10% of the isolates. Sensitivity testing of the isolates against commonly used antibiotics showed that the antimicrobial regimen that we have previously used empirically on such patients may not always be optimal.

Adult↗
PubMed1985

gamma-Aminobutyric acid concentrations are maintained in anoxic turtle brain.

Changes in gamma-aminobutyric acid (GABA) concentrations in the turtle (Pseudemys scripta elegans) brain were studied in situ during prolonged anoxia. With the onset of anoxia, the well-documented rapid increases in GABA found in mammalian brains were not observed in the turtle brain. Although not statistically significant, mean GABA concentrations in the turtle brain were reduced from anesthetized control values during the first 30 min of anoxia. During this initial period brain glutamate content declined. Even after 2 h of nitrogen respiration, GABA in the turtle brain still did not rise above control levels. By the 4th h of anoxia, however, GABA had increased to 147% of control values.

Adenosine Triphosphate↗
PubMed1985

Direct assay for progesterone in saliva: comparison with a direct serum assay.

Direct assays have been described for the estimation of progesterone in serum and saliva. Both methods showed good inter-assay precision over a year, and the serum assay is now being used routinely in clinical laboratories. A highly significant correlation was obtained for progesterone concentrations in matched serum and saliva samples over a wide range of concentrations. The concentrations of progesterone in daily samples taken through the menstrual cycle fell within the range quoted in previous studies. The benefits of direct saliva measurement are described with reference to the long-term assessment of irregular cycles. Care in sample collection is necessary since contamination with agents such as oral cosmetics may result in overestimation of progesterone concentrations.

Antibody Specificity↗