Evidence for rheogenic sodium bicarbonate cotransport in the basolateral membrane of oxyntic cells of frog gastric fundus

Ionic conductance properties of the basolateral cell membrane of oxyntic cells were studied in frog gastric fundus in vitro. After mounting the fundus in a modified Ussing chamber the serosal connective tissue was dissected off and individual oxyntic cells were punctured from the serosal surface with microelectrodes. Under resting conditions the membrane potential averaged –56.9, SD±9.5 mV (n=63), cytoplasm negative. Lowering or raising serosal HCO ₃ ^– concentration from 17.8 to 6 or 36 mmol/l respectively at constant depolarized or hyperpolarized the cell membrane by +16.7 or –18.2 mV respectively. Sudden removal of serosal Na⁺ also depolarized the cell membrane (anomalous Nernst response). Since both the HCO ₃ ^– dependent and the Na⁺ dependent potential changes were strongly depressed by the disulfonic stilbene SITS and since the potential response to HCO ₃ ^– was virtually abolished in Na⁺-free solution we conclude that a rheogenic Na⁺ (HCO ₃ ^– ) _n -cotransport system (n>1) is present in the basolateral cell membrane of oxyntic cells. Its possible role in base transfer during HCl-secretion or HCO ₃ ^– secretion remains to be elucidated.This work was supported by grants Nr. 85.0443.04 and 86.00048.04 from Consiglio Nazionale delle Ricerche, Rome, Italy and by grant Nr. I 37736 from Stiftung Volkswagenwerk, Hannover, FRG     

Antiphospholipid antibodies and the outcome of pregnancy after the first in-vitro fertilization and embryo transfer cycle

Increased antiphospholipid antibody prevalence has been demonstrated by a number of recent studies in in-vitro fertilization (IVF) patients but the potential effects of antiphospholipid antibodies on the different components of the reproductive process and the consideration of whether to test IVF patients for antiphospholipid antibodies are controversial. The present study was undertaken to investigate the possible association between the presence of circulating antiphospholipid antibodies (namely the lupus anticoagulant and anticardiolipin antibodies), among a series of 21 consecutive IVF patients having a clinical spontaneous abortion after their first embryo transfer. As a control group (n=42), the nearest IVF cycle resulting in an ongoing pregnancy before and after each miscarried IVF cycle (i.e. the closest cycles in temporal relationship to the index cycle) was used. One patient (4.8%) in the study group and two women (4.8%) among controls were seropositive for antiphospholipid antibodies. These low and similar seropositivity rates found in the two groups studied lead us to conclude that antiphospholipid antibodies testing in IVF patients should be considered only in those women having repeated failures of implantation/clinical abortion after embryo transfer but not in an infertile general population reaching an IVF programme.      

Assessment of bioequivalence after subcutaneous and intramuscular administration of urinary gonadotrophins

The objective was to demonstrate bioequivalence between s.c. and i.m. administration of Humegon (FSH/LH ratio 1:1) and Normegon (FSH/LH ratio 3:1). In two randomized, single-centre, cross-over studies, 18 healthy volunteers on each formulation were assigned to one of the two administration sequences. Subjects were given single doses of one of the above gonadotrophins after endogenous gonadotrophin production had first been suppressed using high-dose oral contraceptive. Subsequently, rate (Cmax, tmax) and extent (AUC) of absorption of follicle stimulating hormone (FSH) and luteinizing hormone (LH) were determined for 14 days. For Cmax and AUC, analysis of variance (ANOVA) was performed on log-transformed data and for tmax ANOVA was performed on ranks. Intramuscular and s.c. injections of Humegon were bioequivalent with respect to the main pharmacokinetic parameters, being AUC and Cmax of FSH absorption. Intramuscular and s.c. injections of Normegon were bioequivalent with respect to the AUC of FSH and not bioequivalent with respect to the Cmax of FSH. For tmax of FSH as well as for most LH variables of both preparations, bioequivalence could not be proven due to the high intra- and interindividual variability and/or concentrations being close to the detection limit. Thus, the main pharmacokinetic FSH variables after i.m. and s.c. administration of Humegon and Normegon were bioequivalent.      

Is the outcome of in-vitro fertilization and embryo transfer treatment improved by spontaneous or surgical drainage of a hydrosalpinx?

A pilot study was designed to examine whether the outcome of embryo transfer in women with a hydrosalpinx might be improved by surgical drainage of the hydrosalpinx at the time of oocyte collection for in- vitro fertilization treatment. A comparative, controlled but retrospective analysis of the results was performed of all women with infective tubal damage aged <40 years old, who had ovulatory cycles, a normal uterus and a partner with normal spermatozoa. A standardized treatment regimen was used. A maximum of three embryos were transferred. Hydrosalpinx was defined by prior hysterosalpingography and/or laparoscopy with transcervical dye injection. A total of 237 embryo transfer cycles in women with hydrosalpinges (tubal distension not visible in 151, visible but not drained in 30 and drained in 56) were compared with 705 embryo transfer cycles in women with tubal disease but no hydrosalpinx. Results were analysed in the first three cycles but also separately in the first cycle to check for bias. Success rates were higher in the first cycle, but did not significantly influence overall differences. Implantation rates were significantly reduced overall in the hydrosalpinx group (8.0 versus 13.2% for controls; P < 0.001), being 8.3% (P < 0.01) in the subgroup without evident tubal distension and 7.5% (not significant) in the drained hydrosalpinx group. This study shows that tubal damage with distal occlusion is associated with a marked reduction in embryo implantation, even in the absence of obvious fluid distension. Surgical drainage of distended hydrosalpinges appears to offer no benefit.      

Initial evaluation of a continuous speech recognition program for radiology

The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner.     

Biological resurfacing of the knee: a review of surgical management

Lesions of the articular surfaces of the knee have been managed by various techniques over the last 50 years. Surgical management has involved: excising the damaged area, refashioning the underlying bone to produce a fibrous response, and introducing allograft, autograft and synthetic materials to encourage a repair matrix. The techniques and their pitfalls are reviewed and discussed, and suggestions made as to the direction of future studies for the repair of osteochondral lesions in the painful knee.     

Immunological factors in endometriosis-associated reproductive failure: studies in fertile and infertile women with and without endometriosis

Immunopathophysiological mechanisms in endometriosis-associated reproductive failure were studied in appropriate populations: infertile and fertile women with and without endometriosis. The incidence of sera positive for any of the autoantibodies tested among infertile women with endometriosis (n = 25) was similar to that observed in the three control groups [unexplained infertility patients (n = 25) and fertile women with (n = 10) and without (n = 25) endometriosis]. The mean volume of peritoneal fluid was significantly elevated in women with endometriosis (both fertile and infertile) as compared with patients without endometriosis (fertile or infertile). The concentration of peritoneal fluid leukocytes and the percentage of cells positive for macrophage markers were significantly increased and the percentage of T lymphocytes significantly decreased in infertile women with endometriosis but not in patients with unexplained infertility and fertile women with endometriosis, as compared with fertile controls without endometriosis. Macrophages from infertile patients with endometriosis had higher sperm phagocytosis than did those from infertile women without endometriosis or fertile subjects with or without endometriosis. Incidences of serum and peritoneal fluid samples embryotoxic to the in-vitro development of 2-cell mouse embryos were significantly higher in infertile patients with endometriosis than in unexplained infertility patients and fertile women with or without endometriosis. It is concluded that immunological mechanisms of endometriosis-associated infertility exist but that these peritoneal immunological factors in infertile women with endometriosis are related to their subfertility rather than to the presence of ectopic endometrial implants. This is supported by the lack of immunological abnormalities observed among fertile women with endometriosis. These immunological abnormalities are lacking in patients with unexplained infertility.      

The ileoanal J pouch: radiographic evaluation

Endorectal ileoanal pull-through offers an attractive alternative to proctocolectomy and ileostomy for patients with ulcerative colitis, Gardner syndrome, and familial polyposis. To our knowledge, a careful radiographic analysis of the ileum, ileal pouch, and ileoanal anastomosis after ileoanal pull-through has not been reported. Thirty-two patients with ulcerative colitis, Gardner syndrome, and familial polyposis underwent colectomy, mucosal proctectomy, and endorectal ileoanal pull-through of a 15-cm ileal "J" pouch and loop ileostomy. Twenty-five (78%) of 32 of all the pouches radiographically demonstrated spiral folds extending from the middle of the pouch to the pectinate line. Other radiographic features included a mesenteric mass effect, pseudopolyps, and a central lucency that indicated intrapouch sutures. Radiographs provide useful information in the postoperative management of the ileal pull-through.