Fe(III) reduction during pyruvate fermentation by Desulfotomaculum reducens strain MI-1.

Desulfotomaculum reducens MI-1 is a Gram-positive, sulfate-reducing bacterium also capable of reducing several metals, among which is Fe(III). Very limited knowledge is available on the potential mechanism(s) of metal reduction among Gram-positive bacteria, despite their preponderance in the microbial communities that inhabit some inhospitable environments (e.g., thermal or hyperthermal ecosystems, extreme pH or salinity environments, heavy metal or radionuclide contaminated sediments). Here, we show that in the presence of pyruvate, this micro-organism is capable of reducing both soluble Fe(III)-citrate and solid-phase hydrous ferric oxide, although growth is sustained by pyruvate fermentation rather than Fe(III) respiration. Despite the fact that Fe(III) reduction does not support direct energy conservation, D. reducens uses it as a complementary means of discarding excess reducing equivalent after H2 accumulation in the culture headspace renders proton reduction unfavorable. Thus, Fe(III) reduction permits the oxidation of greater amounts of pyruvate than fermentation alone. Fe(III) reduction by D. reducens is mediated by a soluble electron carrier, most likely riboflavin. Additionally, an intracellular electron storage molecule acts as a capacitor and accumulates electrons during pyruvate oxidation for slow release to Fe(III). The reductase responsible for the transfer of electrons from the capacitor to the soluble carrier has not been identified, but data presented here argue against the involvement of c-type cytochromes.

Minimally invasive vaginal hysterectomy using bipolar vessel sealing: preliminary experience with 500 cases.

The objective of our study was to evaluate surgical outcome of minimally invasive vaginal hysterectomy (MIVH), using the bipolar vessel sealing system (BVSS; BiClamp®). The design was a retrospective analysis (Canadian Task-force Classification II-3). The setting was a secondary care hospital. Records of patients who underwent vaginal hysterectomy for benign indications in our centre between November 2005 and March 2011 were reviewed. The demographic patients' data, indications for surgery, patient history with regard to previous surgery, duration of surgery, blood loss (postoperative hemoglobin drop '∆Hb'), perioperative complications, and length of inpatient stay were collected from the medical records. The intervention was vaginal hysterectomy using BVSS (BiClamp®). Results showed that the mean duration of surgery was 48.9 ± 15.3 min (95% CI, 49.2-52.5). The mean duration of hospital stay was 3.2 ± 1.2 days (95% CI, 2.8-3.2). The mean ∆Hb was 1.4 ± 1.8 g/dl. Overall, conversion to laparotomy was required in three cases (0.6%). Only one haemoperitoneum occurred (0.2%) and this is the only case who required blood transfusion. The main indication for VH was uterine prolapse in 52.0% (n = 260) of cases; uterine fibroids in 37.4% (n = 187); adenomyosis uteri in 4.2% (n = 21); cervical dysplasia in 22 patients (4.4%) and in 2% (n = 10) of patients, endometrial hyperplasia and other pathologies were the indications for VH. It was concluded that electrosurgical bipolar vessel sealing by (BiClamp®) can provide a safe and feasible alternative to sutures in vaginal hysterectomy, resulting in reduced operative time and blood loss, with acceptable surgical outcomes.

[Pregnancy and jejuno-ileal bypass]. / Gravidanza e by-pass digiuno-ileale.

The A. describe a full-term pregnancy following jejunoileal by-pass for extreme obesity. They review the problems reported by other A. about pregnancy evolution following this operation.

Endocrinological features and endometrial morphology in climacteric women receiving hormone replacement therapy.

Prolactin (PRL), follicle stimulating hormone (FSH), luteinizing hormone (LH), oestrone (E1), and oestradiol (E2) levels were determined in 204 women who were receiving hormone replacement therapy for their climacteric symptoms. The changes in these hormone levels and the endometrial morphology were studied in order to determine the effects of the replacement therapy. The women were divided into two groups: the first group of 120 women was treated with conjugated oestrogens administered cyclically, plus norethisterone acetate. The second group of 84 women received oral oestriol succinate, also administered cyclically but without additional progestogens. The oestrogen-progestogen therapy resulted in a disappearance of the climacteric symptoms and a significant decrease of FSH and LH levels. Oestriol therapy was less effective than the conjugated oestrogens as a replacement therapy. Oestriol therapy also resulted in a less remarkable decrease of gonadotrophin levels. There were no significant changes in prolactin levels in either group of women. The endometrial histology did not change significantly after either of the two hormone replacement therapies.

An intrauterine progesterone contraceptive system (52 mg) used in pre- and peri-menopausal patients with endometrial hyperplasia.

An intrauterine progesterone contraceptive system (IPCS) (52 mg) was inserted in 25 women with cystic endometrial hyperplasia. Among these women, 11 complained of heavy climacteric symptoms and also received an oestrogen replacement therapy consisting of conjugated oestrogens (0.625 mg/day) administered cyclically for 3 out of 4 wk. Prior to the therapy and after 6 mth of treatment, follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), oestrone (E1) and oestradiol (E2) plasma levels were measured and endometrial histology was evaluated. In the women receiving IPCS treatment alone, there were no significant changes in FSH, LH, PRL, E1 and E2 plasma levels. However, there were remarkable changes found in their endometrial histology. In the remaining women receiving both treatments there was a sharp decrease in FSH and LH plasma levels and an increase in E1 and E2 plasma levels, while the prolactin levels remained unchanged. With the exception of two of these women, the endometrial histology changed remarkably. The endometrial morphology of the two exceptions remained unchanged. All climacteric symptoms disappeared after the administration of both IPCS and the oestrogen replacement therapy. The remarkable changes which did occur in the endometrial histology resulted in a less active glandular epithelium and stromal decidual formation, thus proving a useful effect of treatment.