Twist-bending of a 90° elbow or pipe bend

Out of plane bending by an end couple applied to a 90° elbow or pipe bend of circular cross-section is considered. There is conversion of bending to twist so that at 90° the elbow is held in equilibrium by a twist couple. Using the methods of toroidal elasticity, the six stresses of the first order stress field are determined from the zero-order field. The zero-order field constitutes a permissible initial deformation as verified by strain compatibility equations.The equations in the text are derived from the general theory of toroidal elasticity by applying the method of successive approximations. The equations of the general theory are expanded in a series in $\text{1}\text{R}$ (where R is the toroidal radius). This leads to the working equations given in the paper.     

Microbial production,structure elucidation and bioconversion of sophorose lipids

Cultivation of Torulopsis bombicola ATCC 22214 on a mixture of glucose and oleic acid (A) or oleic acid alone (B) produced large amounts of sophorose lipids. In the case of A, 38 g/1 of crude product were finally isolated; fermentation B led to 77 g/1. After separation by MPLC and TLC, six glycolipids were obtained and identified by NMR and fast atom bombardment-mass spectrometry (FAB-MS). In general, a 17-hydroxyocta-decanoic acid at the C-1’ -position and acetate groups at the C-6’ -and C-6’ -positions of sophorose were found as substituents in the lactone and acidic forms of these lipids. The composition of product from A was as follows: 62% of sophorolipid 1’,4’ -lactone 6’ ,6’ -diacetate (SL-1), 4% of sophorolipid 1’,4’-lactone 6’-monoacetate (SL-2), 4% of sophorolipid 1’,4 ’-lactone (SL-3), 4% of sophorolipid 1’,6’-and l’,6’-lactones (SL-4a,b), 4% of sophorolipid 6’-monoacetate acid (SL-5), 4% of sophorolipid acid (SL-6) and finally 17% of other lipids. In B, the principal lactone (40%) had a double bond in the fatty acid moiety; the other components were identical with the above products. Yields of 13% SL-2 and of 35% lipids containing no carbohydrate were significant. SL-1 was deacetylated to SL-3 (yield: 25-307c) using acetyl-esterase in a two-phase system (cyclohexane/water). To whom correspondence should be addressed.     

The lung in AIDS]

The aim of this study was to underline the important role played by respiratory tract pathologies in HIV-infected subjects and to evaluate the incidence of respiratory pathologies in HIV-positive subjects in the province of Cosenza. After examining recently reported data, the authors analyse the patients studied by the Infectious Disease and Pneumology Divisions of the United Hospitals of Cosenza with the collaboration of the Virology Unit over the two-year period 1992-1994. As well as the lower incidence of HIV infection in this area compared to the rest of Italy, the paper highlights the reduced percentage of concomitant respiratory pathologies. The authors attempt to interpret the significance of these results.     

Delayed childbearing--are there any risks?

OBJECTIVE: To determine whether women delivering their first child at age 35 years or older are at increased risk of adverse (non-genetic) pregnancy outcomes. DESIGN AND SETTING: A cross-sectional analytic study of singleton deliveries in Northern Sydney Area Health Service (NSAHS) hospitals. PARTICIPANTS: All women aged > or = 20 years delivering their first child between 1 January 1990 and 31 December 1991. MAIN OUTCOME MEASURES: Obstetric complications and procedures, type of delivery and neonatal outcomes. RESULTS: Compared with women aged 20-29 years, women delivering their first child at > or = 35 years were at increased risk of pre-existing maternal hypertension (adjusted odds ratio [OR], 3.5; 95% confidence interval [CI], 1.7-7.0), antepartum haemorrhage (adjusted OR, 2.4; 95% CI, 1.6-3.7), preterm delivery (33-36 weeks) (adjusted OR, 2.0; 95% CI, 1.5-2.8) and breech presentation (adjusted OR, 1.8; 95% CI, 1.3-2.4). Women aged > or = 35 years were also substantially more likely to have an operative delivery, induced labour and/or epidural anaesthesia. Neither these women nor their infants were at increased risk of pregnancy-induced hypertension, gestational diabetes, threatened premature labour, postpartum haemorrhage, very preterm delivery (< or = 32 weeks), perinatal death, low Apgar scores or the need for neonatal resuscitation. CONCLUSIONS: Women who delay the birth of their first child face some increased risks, but these risks, for the most part, are manageable in the context of modern obstetric care.     

Synthesis and mutagenicity of a series of nitrated carbazoles and hydroxycarbazoles

The effects of a component of an Oriental medicine and green tea plants utilized for the traditional beverage on the proliferation of mesangial cells were determined in terms of the 3H-thymidine uptake. When magnesium lithospermate B was added to the medium of the mesangial cell culture, it suppressed the proliferation of mesangial cells at a concentration of 50 micrograms/ml. The 3H-thymidine uptake began to display an inhibitory action from the 6.25 micrograms/ml (-)-epicatechin 3-O-gallate, (-)-epigallocatechin 3-O-gallate or green tea tannin mixture, showing a more conspicuous inhibition at 50 micrograms/ml that did the magnesium lithospermate B at the corresponding concentration. In particular, (-)-epigallocatechin 3-O-gallate, the predominant component of the green tea tannin mixture, exerted an inhibitory effect at a relatively low concentration.     

Escherichia vulneris infection. Report of 2 cases

BACKGROUND: Escherichia vulneris is an enterobacteriaceae seldom isolated in microbiology laboratories. We report two cases of infection with positive cultures for this microorganism. METHODS: Microbiological cultures of wound secretion and peritoneal fluid on usual media. Identification by PASCO and API 20E systems. Antimicrobial sensitivity was performed by a commercial microdilution system. RESULTS: The first case is a postsurgical hand infection from which was isolated Escherichia vulneris with Enterococcus faecium, it shows the typical presentation of infection by this bacteria. The second case consists of a peritonitis after aggressive abdominal surgery. In the peritoneal fluid culture, Escherichia vulneris and Cedecea neteri were recovered. CONCLUSIONS: The isolation of Escherichia vulneris has not been reported previously in Spain. We contribute towards its better knowledge with two clinical reports: a typical infection and an exceptional isolation from peritoneal fluid.     

An investigation of the viral pathogenesis of Kikuchi-Fujimoto disease. Lack of evidence for Epstein-Barr virus or human herpesvirus type 6 as the causative agents

Histiocytic necrotizing lymphadenitis of Kikuchi and Fujimoto is a well-defined clinicopathologic entity of unknown cause. Both the Epstein-Barr virus (EBV) and human herpesvirus type 6 (HHV-6) have been suggested as potential etiologic agents. Twenty cases of Kikuchi-Fujimoto disease were studied for the presence of EBV DNA and HHV-6 DNA by the polymerase chain reaction (PCR), and in situ hybridization in the case of EBV. Cellular DNA from sections of formalin-fixed, paraffin-embedded lymph node tissue was amplified using the PCR technique and oligonucleotide primers to the EBV BamH1 W, lymphocyte-determined membrane antigen, or the EBNA-1 region. These studies were performed in three separate laboratories. In addition, 12 cases were examined by in situ hybridization, eight of which had shown at least one positive PCR signal for EBV. The presence of HHV-6 was assessed by PCR using primers to part of the pZVH14 sequence. Biopsy specimens from eight patients (40%) showed a strong positive signal for EBV in at least one laboratory, while an additional three specimens (15%) showed a weaker positive signal. Five cases studied showed rare positive cells by in situ hybridization, and one case had scattered positive cells. All samples lacked HHV-6 genomic templates. These findings indicate that HHV-6 does not play a role in the pathogenesis of Kikuchi-Fujimoto disease and do not implicate EBV as a causal agent for Kikuchi-Fujimoto disease, since EBV was detected in only a fraction of cases with a low number of positive cells detected by in situ hybridization. Further, some discrepancies were identified in the positive results for EBV in samples studied by multiple laboratories. These results indicate that inconsistent results by PCR may occur with very low levels of viral genomes and that different laboratories perform DNA amplification at different efficiencies. Alternatively, laboratory contamination may give rise to false-positive results. Therefore, a positive result for EBV should be interpreted with caution and should be confirmed by repeated study (PCR) or by independent methodology (in situ hybridization).     

Plasma angiotensin(1-7) immunoreactivity is increased by salt load, water deprivation, and hemorrhage

In this study we investigated the effects of dehydration and hemorrhage on circulating levels of the heptapeptide, angiotensin(1-7). In water-deprived rats, a twofold increase in plasma angiotensin(1-7) was associated with similar increases in plasma renin activity, and angiotensin I and angiotensin II levels. In salt-loaded rats, plasma angiotensin(1-7) levels increased fourfold; however, other components of the renin-angiotensin system were suppressed or unchanged. In salt-loaded rats, increases in plasma angiotensin II levels in response to hemorrhage in normal rats were severely blunted, whereas angiotensin(1-7) plasma levels increased proportionately to the loss of blood volume. These results suggest that angiotensin(1-7) plasma concentration can be selectively regulated during dehydration and hemorrhage.