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M Potts

Publications and source records attributed to M Potts.

At least 127 records · Page 7Linked to original sources

Variation in Phospholipid Ester-Linked Fatty Acids and Carotenoids of Desiccated Nostoc commune (Cyanobacteria) from Different Geographic Locations.

Profiles of phospholipid fatty acids and carotenoids in desiccated Nostoc commune (cyanobacteria) collected from China, Federal Republic of Germany, and Antarctica and in axenic cultures of the desiccation-tolerant strains N. commune UTEX 584 and Hydrocoleum strain GOEI were analyzed. The phospholipid fatty acid contents of the three samples of desiccated Nostoc species were all similar, and the dominant compounds were 16:1omega7c, 16:0, 18:2omega6, 18:3omega3, and 18:1omega7c. In comparison with the field materials, N. commune UTEX 584 had a much higher ratio of 18:2omega6 to 18:3omega3 (5.36) and a significantly lower ratio of 18:1omega7c to 18:1omega9c (1.86). Compound 18:3 was present in large amounts in the samples of desiccated Nostoc species which had been subject, in situ, to repeated cycles of drying and rewetting, but represented only a small fraction of the total fatty acids of the strains grown in liquid culture. This finding is in contrast to the data obtained from studies on the effects of drought and water stress on higher plants. Field materials of Nostoc species contained, in contrast to the axenic strains, significant amounts of apocarotenoids and a P384 pigment which, upon reduction with NaBH(4), yielded a mixture of a chlorophyll derivative and a compound with an absorption maximum of 451 nm. A clear distinction can be made between the carotenoid contents of the axenic cultures and the desiccated field materials. In the former, beta-carotene and echinenone predominate; in the latter, canthaxanthin and the beta-gamma series of carotenoids are found.

Journal Article↗

In-hospital maternal mortality risk by cesarean and vaginal deliveries in two less developed countries--a descriptive study.

Cesarean deliveries are increasing in both developed countries and less developed countries (LDCs). Recent studies in the U.S. have revealed a significantly higher mortality risk for women who delivered abdominally than for those who delivered vaginally, even when the effect of the conditions which necessitated cesarean delivery was taken into account. We chose for study from an international maternity monitoring network, five centers from two LDCs that reported an in-hospital maternal mortality rate (MMR) of around 10 per 1000 parturient women. The pooled data revealed an MMR of 5.1 per 1000 women with vaginal deliveries. For women with cesarean delivery, the total MMR was 36.2 and the MMR attributable to cesarean section was estimated to be 12.8; both rates were per 1000 procedures. The leading cause of death was eclampsia for the vaginal deliveries and sepsis for the cesarean deliveries. The risk of maternal mortality inherent with the cesarean section procedure per se (not counting the risk associated with the labor and delivery complications that necessitated cesarean section) as well as the practical avoidability of maternal deaths for either mode of delivery in these LDC hospitals are discussed.

Anesthesia, Obstetrical↗

Rare events associated with tubal sterilizations: an international experience.

The results from previous analyses of an international data set collected by Family Health International are reviewed in relation to the incidence, severity, risk factors, and outcomes of rare events associated with tubal sterilization. The rare events included for review, by sequence of their relationship to the tubal sterilization procedure are: luteal phase pregnancy, intraoperative complications (uterine perforation, unintended laparotomy required for completion of the laparoscopic procedure, and technical failure in tubal ring sterilization), deaths, early readmission following laparoscopic sterilization, hysterectomy after laparoscopic sterilization, and pregnancy (intrauterine and ectopic) conceived after tubal sterilization. The widespread use of this method of contraception has important public health implications, and awareness of these events will help clinicians minimize such incidences and better deal with them when they arise.

Female↗

Purification and Biochemical Analysis of the Cytoplasmic Membrane from the Desiccation-Tolerant Cyanobacterium Nostoc commune UTEX 584.

The cytoplasmic membrane of the heterocystous cyanobacterium Nostoc commune UTEX 584 was isolated free of thylakoids and phycobiliprotein-membrane complexes by flotation centrifugation. Purified membranes had a buoyant density of 1.07 g cm and were bright orange. Twelve major proteins were detected in the membrane, and of these, the most abundant had molecular masses of 83, 71, 68, 51, and 46 kilodaltons. The ester-linked fatty acids of the methanol fraction contained 16:0, 18:0, 18:1omega9c, 20:0, and 20:3omega3 with no traces of hydroxy fatty acids. Compound 20:3omega3 represented 56.8% of the total fatty acid methyl esters, a feature which distinguishes the cell membrane of N. commune UTEX 584 from those of all other cyanobacteria which have been characterized to date. Fatty acid 18:3 was not detected. Carotenoids were analyzed by highperformance liquid chromatography. The cytoplasmic membrane contained beta-carotene and echinenone as the dominant carotenoids and lacked chlorophyll a and pheophytin a. Whole cells contained beta-carotene and echinenone, and lesser amounts of zeaxanthin and (3R)-cryptoxanthin.

Journal Article↗

Reproductive mortality in two developing countries.

Reproductive mortality includes mortality attributable to pregnancy, termination of pregnancy, childbirth and its sequelae, and contraception. Reproductive mortality has been estimated for the United Kingdom, the United States, and for states of the US. However, it has not previously been measured for developing countries, where maternal mortality often remains distressingly high. This paper reports on data from one governorate of Egypt, where reproductive mortality was 46 per 100,000 married women ages 15-49 (2.2 per cent of this was attributable to contraception), and one province of Indonesia, where reproductive mortality was 70 per 100,000 (of which 1.4 per cent was due to contraception). In both locations, complications of pregnancy and childbirth were a leading cause of death in the age group studied (the first cause in Indonesia, second in Egypt). Contraceptive prevalence was 24 per cent of married women ages 15-49 in Egypt and 48 per cent of this age group in Indonesia.

Adolescent↗

Methodological issues in collecting data from traditional birth attendants.

Information on the activities, practices and social context of pregnancy and delivery care provided by traditional birth attendants (TBA) is a critical requirement in planning, monitoring and evaluating maternal health programs in many countries. As a result of experimental studies in which such information was obtained by a variety of methods, and a review of alternative methodologies, a set of guidelines has been developed for the collection of such information. High-lighted are the need for good background knowledge on the local situation, involving TBAs themselves in design and collecting methods, a system of supervision to ensure adequate training and careful monitoring, and finally sharing the findings with the TBAs as well as with health officials.

Brazil↗

Protein synthesis and proteolysis in immobilized cells of the cyanobacterium Nostoc commune UTEX 584 exposed to matric water stress.

Cells of the cyanobacterium Nostoc commune UTEX 584 in exponential growth were subjected to acute water stress by immobilizing them on solid supports and drying them at a matric water potential (psi m) of -99.5 MPa. Cells which had been grown in the presence of Na235SO4 before immobilization and rapid drying continued to incorporate 35S into protein for 90 min. This incorporation was inhibited by chloramphenicol. No unique proteins appeared to be synthesized during this time. Upon further drying, the level of incorporation of 35S in protein began to decrease. In contrast, there was an apparent increase in the level of certain phycobiliprotein subunits in solubilized protein extracts of these cells. Extensive proteolysis was detected after prolonged desiccation (17 days) of the cells in the light, although they still remained intact. Phycobilisomes became dissociated in both light- and dark-stored desiccated material.

Bacterial Proteins↗

Non-surgical tubal occlusion.

Out of 151 women provided with chemical female sterilization with 3 insertions of 250 mg of quinacrine spaced 1 month apart, there were 7 pregnancies in 3 years. If these pregnancies were a result of failure to occlude the entrance to 1 or both fallopian tubes, birth events should decrease exponentially with time. Unexpectedly, the low failure rate has not decreased significantly over the 3-year observation period.

Acridines↗