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M Rodgers

Publications and source records attributed to M Rodgers.

At least 55 records · Page 3Linked to original sources
PubMed1992

Human chorionic gonadotrophin contributes to the bioactivity of Pergonal.

OBJECTIVE: We examined batch variation in the LH-like bioactive content of Pergonal and determined whether hCG contributes to this. DESIGN: Random selection of three batches of Pergonal, consisting of three ampoules in each batch. MEASUREMENTS: The LH content in each ampoule was determined by radioimmunoassay (R-LH), immunoradiometric assay (I-LH) and in vitro Leydig cell bioassay (B-LH) using the urinary hMG International Standard 70/45. Human chorionic gonadotrophin was determined by immunoradiometric assay (I-hCG) using the hCG IRP 75/537. The isohormone content of each batch was examined by chromatofocussing over the range pH 4.5-7.0 and the fractions collected were assayed for LH and hCG content. The variability in potency between batches was assessed by single factor analysis of variance. RESULTS: The gonadotrophin content of each batch (IU/ampoule, mean +/- SEM, n = 3 ampoules) was R-LH (40.9 +/- 0.5, 40.8 +/- 0.2, 39.3 +/- 0.7, P > 0.15), I-LH (39.0 +/- 1.5, 28.3 +/- 0.8, 36.9 +/- 3.3, P < 0.001), B-LH (27.3 +/- 0.3, 12.0 +/- 0.9, 19.3 +/- 0.9, P < 0.001) and I-hCG (16.4 +/- 0.7, 11.7 +/- 0.2, 10.5 +/- 0.5, P < 0.001). The chromatofocussing recoveries below pH 5.5 expressed as a percentage of the total amount of analyte eluted from the column and collated for all three batches of Pergonal were (mean % +/- SD, n = 3 batches) R-LH (58.4 +/- 4.0), I-LH (41.3 +/- 7.5), B-LH (81.4 +/- 2.8) and I-hCG (87.8 +/- 3.7). CONCLUSIONS: There was significant batch variation in the I-LH, B-LH and I-hCG (P < 0.001) but not the R-LH (P > 0.15) content of Pergonal. More than 80% of the total B-LH recovery chromatofocussed below pH 5.5 and corresponded to the region of highest I-hCG (> 87%) and lowest I-LH (< 42%) recovery. This was highly suggestive of hCG contributing to the LH-like bioactivity of Pergonal.

Chorionic Gonadotropin↗
PubMed1992

Multidrug resistance in Leishmania donovani is conferred by amplification of a gene homologous to the mammalian mdr1 gene.

Drug resistance is a major impediment to the effective treatment of parasitic diseases. The role of multidrug resistance (mdr) genes and their products in this drug resistance phenomenon, however, remains controversial. In order to determine whether mdr gene amplification and overexpression can be connected to a multidrug resistance phenotype in parasitic protozoa, a mutant strain of Leishmania donovani was generated by virtue of its ability to proliferate in medium containing increasing concentrations of vinblastine. The vinblastine-resistant strain, VINB1000, displayed a cross-resistance to puromycin and the anthracyclines, a growth phenotype that could be attributed to an impaired ability to accumulate the toxic drugs. By using the polymerase chain reaction, two different DNA fragments, LEMDR06 and LEMDRF2, were amplified from leishmanial genomic DNA, and each amplified fragment encoded a product that was significantly homologous to parts of the mammalian P-glycoprotein. In the VINB1000 strain, the mdr gene recognized by the LEMDR06 probe was amplified approximately 50-fold in copy number, whereas the mdr genes that hybridized to LEMDRF2 or to a fragment of the previously characterized ltpgpA gene were not amplified. Moreover, the VINB1000 cell line expressed a LEMDR06 gene transcript of 12.5 kb in size that was not detected in the parental wild-type strain. To furnish a functional test for mdr gene amplification and expression in L. donovani, the L. donovani gene recognized by the LEMDR06 polymerase chain reaction product, ldmdr1, was isolated from a genomic library, transfected into wild-type cells, and amplified over 500-fold by selection in 0.5 mg of G418 per ml. The resulting transfectants were resistant to all drugs to which VINB1000 cells were resistant and sensitive to all drugs to which VINB1000 cells were sensitive. These studies demonstrate that amplification of the ldmdr1 gene either by direct selection or subsequent to transfection can confer a drug-resistant phenotype in parasitic protozoa similar to that observed for MDR mammalian cells.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1991

Leishmaniasis in a domestic goat in Kenya.

The pathological and electron-microscopic features of the first case of autochthonous leishmaniasis affecting a domestic goat in Kenya are described. They are similar to what have been described in man and other animals. Using a short amino-acid sequence common to all the species of leishmania as primers for kDNA synthesis, the intervening sequence of 120 bases was amplified in the goat's tissues by polymerase chain reaction (PCR). The leishmania kinetoplast DNA sequence was detected in all the different infected tissues of the goat examined. The sensitivity and specificity of this assay are discussed. The result of the assay used was consistent with the parasite being either L. major or L. aethiopica as the infecting agent. The isoenzyme studies were consistent with L. aethiopica as the strain responsible for this goat's infection. The control of leishmaniasis and its vector must take into account the potential role of animal reservoirs in the environment. Even though Kenya and other East African countries are endemic for kala-azar, the presence of kala-azar in goats is of considerable veterinary public health importance in Africa. Efforts must not be spared to identify and detect other possible animal reservoirs in the subregion. Using DNA amplification techniques, which are sensitive and specific, such as the one described in this paper, sera and other biological fluids and tissues from different animal species should be utilized for detecting additional reservoirs for leishmania parasites particularly in known endemic areas of the world.

Animals↗
PubMed1989

Three year hospital experience with control of major obesity by VLCD in medically compromised individuals.

A very low calorie formula diet (VLCD) with physician and dietitian support was used to achieve and maintain weight loss in 408 overweight patients, referred by consultants because of concurrent health problems. The patients had failed to lose weight on conventional diets, and their obesity was considered a significant risk factor in their health. Using 330 or 405 kcal formula diets, the mean rate of weight loss in men was 1.87 kg/week and in women 1.27 kg/week. Women sustained the dieting process over longer periods, with a time to maximum weight loss of 5-72 weeks (mean 24) compared to the achievement in men of 4-40 weeks (mean 12.5). Sixteen per cent of the patients dropped out in the first 3 weeks. Of the remaining 84 per cent, weight loss to within 80-100 per cent BMI 25 (target weight) was achieved by 53 per cent men and 46 per cent women who had completed more than 5 weeks dieting. Women were more complaint than men at weight maintenance follow-up and 58 per cent of the start group were observed for more than 50 weeks (50-164), only 10 per cent experiencing weight regain of 20-70 per cent. Physician support was required to adjust medication in patients attending. Complications of obesity were remarkably improved after weight loss.

Adolescent↗
PubMed1981

Serum lipids in a teenage population: geographic, seasonal and familial factors.

The lipid results of a cross-sectional study of cardiovascular disease risk factors in over 600 13-18 year olds drawn from general practices in contrasting areas are reported. Differences were noted between the 3 practices, including a significant variation in the blood group distribution. HDL cholesterol showed a marked variation between the 3 practices which was unlikely to be due solely to seasonal variation. Alcohol consumption though not an univariate correlate of HDL cholesterol was however a strong partial correlate, as were age, height, sexual maturation, adiposity and smoking. Using 6 factors in each sex, 13% of the interchild variance of HDL cholesterol in boys could be explained in a multiple linear regression analysis, and 8% in girls. Including the practice variation as a further independent variable increased the explanation in 18% in boys and 15% in girls. An intraclass correlation (sib-sib) of 0.36 was found for HDL cholesterol, suggesting a strong familial influence. The implications of these results are discussed, along with the difficulties of screening for hyperlipidaemia in this age group.

Adolescent↗
PubMed1980

Changes in blood lipids and blood pressure during adolescence.

A total of 625 adolescents from three general practices participated in a cross-sectional study of cardiovascular disease risk factors. The girls had higher serum total and high density lipoprotein (HDL) cholesterol concentrations than the boys, while the boys had higher serum triglyceride concentrations. Smoking (equally prevalent in both sexes) was associated with lower HDL cholesterol concentrations, particularly in boys, while in girls use of oral contraceptives was associated with higher total cholesterol and lower HDL cholesterol concentrations showed striking associations with age, height, and sexual maturation in boys, but not in girls. Triglyceride concentrations were associated with age in boys. Systolic blood pressure and serum urate concentrations were higher in boys and rose steeply with age, but no age association was seen for urate concentrations or systolic blood pressure in girls or for diastolic pressures in either sex. Girls, however, had higher diastolic pressures. There was a strong association between urate concentration and the other cardiovascular disease risk factors, especially HDL cholesterol. Adolescence is associated with considerable changes in cardiovascular disease risk factors, and there are striking sex differences in these changes.

Adolescent↗
PubMed1980

Two new non-barbiturate buffers for electrophoresis of serum proteins on cellulose acetate membranes.

Two new non-barbiturate buffers have been formulated for serum protein electrophoresis on cellulose acetate membranes. Both buffers give five distrinct fractions and are suitable for all systems, but have been primarily designed to meet the needs of the Gelman "Sepratek" system. One buffer is a tris(hydroxymethyl)aminomethane (Tris)/hippurate formulation; the other is composed of Tris/N-[tris(hydroxymethyl)methyl]glycine (Tricine)/sodium chloride/sodium salicylate. Both buffers allow reliable quantitation of protein fractions, giving results that correlated well with those obtained from barbiturate separations. The major advantage of these buffers is that they do not contain drugs of abuse.

Barbiturates↗
PubMed1976

Can digoxin dose requirements be predicted?

A search for patient variables relevant to digoxin dose requirements was made in fourty-three patients with a wide range of renal and hepatic function. The daily dose of digoxin to achieve a mean serum concentration of 1.5 ng/ml, the standardized dose, was calculated for each patient. The standardized dose correlated significantly with the following variables, in descending order of correlation coefficient; creatinine clearance, serum creatinine concentration, body weight and serum albumin concentration. An equation containing the two independent variables, creatinine clearance and serum albumin concentration, had a significantly stronger correlation with standardized dose than creatinine clearance alone. Attempts were made in each patient to predict the standardized dose using both empirical prescribing methods and the published nomograms. Although a maximum of 70% of the variance of the standardized dose was explained, this corresponded approximately to one patient in three having a predicted dose outside the 95% confidnece limits for the standardized dose. There remain important sources of individual variation in digoxin dose requirements yet to be identified. Future application of empirical prescribing methods, such as multiple linear regression and Bayes' theorem, to prescription for large, defined patient groups may improve dose prediction for individual patients.

Digoxin↗
PubMedDate not supplied

Recirculating sand filters for treatment of synthetic dairy parlor washings.

Land-spreading and spray irrigation are the most widely used practices for the disposal of dairy wastewaters in Ireland but in some cases there can be problems due to contamination of surface and ground water. The use of intermittent sand filtration has been suggested as an alternative treatment process. However, a single pass through a sand filter limits denitrification because of the absence of reducing conditions following nitrification and the lack of an available carbon source. This leads to poor total nitrogen (TN) reduction and an effluent that is high in nitrate nitrogen (NO3-N). This paper follows a previous paper in which two instrumented stratified sand filter columns (0.9 and 0.425 m deep, and both 0.3 m in diameter) were intermittently loaded with synthetic dairy parlor washings at a number of hydraulic loading rates, leading to a TN reduction of 27 to 41%. In the present study, under a chemical oxygen demand (COD) of 23.4 g m(-2) d(-1), the TN was reduced by 83.2% when three-quarters of the sand filter effluent was recirculated through an anoxic zone. This produced an effluent NO3-N concentration of 60 mg L(-1). With recirculation, the improvement in the removal of organic matter and ammonia N (NH4-N) is minimal. Recirculating sand filters appear to offer a mechanically simple and effective method for the removal of nitrogen from dairy parlor effluents and are a significant improvement over a single-pass sand filter.

Animals↗
PubMedDate not supplied

Acute suppurative thyroiditis in a primary intrathoracic goiter.

OBJECTIVE: To describe a case of acute suppurative thyroiditis and focal abscess formation in a patient with a primary intrathoracic goiter. METHODS: We summarize the initial clinical manifestations, the pathologic findings, and the surgical treatment of a woman with an enlarging mediastinal mass. RESULTS: A 41-year-old woman had a fever and a sudden increase in severity of compressive symptoms after a remote urinary tract infection. Smears from an intraoperative fine-needle aspiration biopsy showed necrotic debris, polymorphonuclear leukocytes, hemosiderin-laden macrophages, and degenerated follicular epithelial cells. Urine and tissue cultures grew Escherichia coli. The patient underwent resection of an 800-g primary intrathoracic goiter with associated degeneration, necrosis, hemorrhage, and abscess formation. CONCLUSION: To our knowledge, this is the first reported case of acute suppurative thyroiditis and abscess formation occurring within a primary intrathoracic goiter.

Journal Article↗