Defibrination of blood plasma for use in serological tests for syphilis

Syphilitic plasma can be salvaged from discarded blood donations and converted to serum by defibrination. Sixty-nine units of plasma were treated with a stock solution of 100 U of thrombin per ml in 1 M calcium chloride and then with a 10% (wt/vol) solution of kaolin. Fibrinogen concentrations detected in initial plasma samples ranged from 94 to 4970 mg/liter (mean, 2532 mg/liter) for samples that were reactive by the rapid plasma reagin circle card test (RPR) and from 314 to 2742 mg/liter (mean 1528 mg/liter) for samples that were not reactive by the RPR. The treated samples showed no measurable fibrinogen remaining after the defibrination process. In the nontreponemal RPR for syphilis, 86% of the treated plasma samples retained the same endpoint titer as that of the initial plasma sample. When the Treponema pallidum passive-particle-agglutination test was used, 98% retained the same reactivity. In the Captia Syphilis-G enzyme immunoassay, 89% of the treated samples demonstrated no change in reactivity index, and in the fluorescent treponemal antibody absorption test, 96% showed no reduction in fluorescence. Human sera containing antibodies to syphilis are used at the Centers for Disease Control and Prevention for the preparation of reference controls or as samples for proficiency testing. Finding reactive sera is becoming more difficult due to the general decline of syphilis cases in the United States. The decreasing availability of these sera can be alleviated by salvaging plasma and converting it to serum.     

Prenatal haloperidol treatment decreases nerve growth factor receptor and mRNA in neonate rat forebrain.

Pregnant rats were treated daily with haloperidol (2 mg/kg) for 11 days until 1 day before birth. The levels of nerve growth factor (NGF), its receptor (NGFR) and NGFR-mRNA were measured in forebrain of 2-day old postnatal rats. Using Northern blot analysis, we observed a decrease in NGFR-mRNA. Furthermore, in binding studies, Kd and Bmax of treated rats were lower than in controls, but only in the low affinity binding sites. However NGF and its mRNA did not change after haloperidol treatment. In conclusion, our results suggest that prenatal haloperidol treatment can modify the development of forebrain cells, by changing NGFR expression.     

Exercise and brain catecholamine relationships with brown adipose tissue and whole-body oxygen consumption in rats

Brown Adipose Tissue (BAT) is thought to maintain caloric homeostasis by increasing its metabolic rate during periods of energy surfeit or low environmental temperatures and decreasing it during periods of deprivation or high environmental temperatures. The present study investigated the relationship of BAT and whole-body metabolic rate with negative energy balance induced by a minimally stressful exercise regimen. Twenty-four rats exercised in a running wheel for 2 hours per day for 8 weeks for food reinforcement either under a variable ratio or variable time schedule. Whole-body oxygen consumption and the thermic effect of a test meal were then measured, the rats sacrificed, BAT weight and oxygen consumption measured, and the brains assayed for catecholamines. Food intake was found to be positively correlated with expenditure either in the form of exercise, overnight weight loss, or BAT metabolic rate. Brain dopamine concentrations were found to be related to BAT metabolic rate which was in turn related to the amount of weight lost overnight and the amount of food intake. Running was positively correlated with BAT metabolic rate, suggesting that brown adipose tissue is not simply an organ of caloric homeostasis or thermoregulation. BAT, then, appears to be a multi-purpose tool used by a number of systems which regulate body temperature and energy metabolism.     

Evolution of MHC-G in humans and primates based on three new 3'UT polymorphisms

MHC-G is a class Ib (non-classical) major histocompatibility complex (MHC) whose functional and evolutionary characteristics are still under scrutiny. The study of noncoding sequences in the MHC genes may provide important phylogenetic information. In this work we have sequenced the MHC-G exon 8, which encodes for the 3'UT region, in different species of primates. It has been shown that: (1) a previously described 14 base pair (bp) deletion polymorphism is human-specific and the HLA-G alleles may be classified according to its absence or presence; (2) another newly described 3 bp deletion/insertion polymorphism is also human-specific; and (3) another newly described 51 bp deletion polymorphism is common to Pongidae and humans, but is not found in other primates belonging to the Cercopithecinae family. A hypothesis on the evolutionary pathway of this gene is put forward in the light of these findings.     

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.      

Respiratory mechanics and pleural remodelling in pleurodesis induced by barium sulphate

The aim of this study was to determine whether an intrapleural injection of barium sulphate would produce pleurodesis in rats. Additionally, respiratory mechanics and pleural remodelling were analysed. Single intrapleural injection of barium sulphate (100%) or saline was given to Wistar rats. Respiratory system, lung, and chest wall elastic, resistive and viscoelastic/inhomogeneous pressures were measured by the end-inflation occlusion method at 2 and 30 days after injection. The pleura were examined for gross and histopathological evidence of pleural inflammation and fibrosis, and the underlying lungs were also studied by morphometry. All pulmonary mechanical parameters increased at day 2, but were not different from control at 30 days after injection. Chest wall mechanical parameters did not change. Macroscopic evaluation demonstrated pleural adherence without haemothorax. Histopathologic analysis showed pleural inflammation and fibrosis. There was no alveolar inflammation or fibrosis in both groups. In conclusion, barium sulphate induced pleurodesis with either no changes in respiratory mechanics or lung lesion at day 30.     

Shashi XLMR syndrome: report of a second family

This report describes a family with mental retardation in two brothers. The pedigree is consistent with either X-linked mental retardation or autosomal recessive inheritance. The clinical features consist of coarse face, prominent lower lip, large testes, and obesity. This same constellation of findings was observed in a family with X-linked mental retardation (XLMR) reported by Shashi et al. [2000: Am J Hum Genet 66:469-479]. Furthermore, haplotype analysis was consistent with localization of the Shashi XLMR syndrome in Xq26-q27. Thus, the family likely represents a second occurrence of the Shashi XLMR syndrome.     

Limb preference after unilateral pyramidotomy in adult and neonatal rats

As previously reported, unilateral pyramidotomy in newborn rats results in the development of an aberrant ipsilateral corticospinal tract that originates from the intact side. In the present study, limb preference after unilateral pyramidotomy in adult and neonatal rats was examined in search of differences that might correlate with this aberrant tract. However, no significant differences were observed between the two groups. Postoperatively, adult animals preferred the limb corresponding to the intact corticospinal tract in spite of a pre- and postoperative testing bias toward the opposite limb. Similarly, the animals that sustained neonatal lesion followed by testing at maturity also preferred the limb corresponding to the normal crossed corticospinal tract.     

Myofibroblastic differentiation in simple peritoneal sclerosis

OBJECTIVE: To analyze the presence of myofibroblasts in a series of peritoneal dialysis (PD) patients with simple sclerosis and non-PD, uremic patients. Since there is a close correlation between active fibrosis and myofibroblastic differentiation we wanted to test if myofibroblasts are present in uremic, non-PD peritoneal samples. To determine if there are correlations between myofibroblastic presence and other functional and morphologic peritoneal parameters. METHODS: Biopsies were collected from three patient groups: 1) Normal control samples (n = 15) of parietal and visceral peritoneum 2) non-PD uremic patients (n = 16); and 3) uremic patients on PD (n = 32). Peritoneal morphologic and functional parameters and immunohistochemical expression of alfa-smooth muscle actin was analyzed in each case. Vascular endothelial growth factor (VEGF), bcl-2 anti-apoptotic protein, and progesterone receptor was evaluated in a subset of cases. RESULTS: Myofibroblasts were present in 56.3% of the patients with PD-related simple sclerosis. In most cases they were distributed in the upper submesothelial area. None of the biopsies from normal controls and uremic, non-PD patients showed myofibroblasts. Within the group of PD patients, myofibroblasts showed no correlation with time on dialysis, urea/creatinine MTAC, episodes of peritonitis, submesothelial thickening, hyalinizing vasculopathy or mesothelial status. In a subset of PD patients VEGF expression was observed in submesothelial fibroblastic cells. No expression of progesterone receptor or bcl-2 was observed. CONCLUSIONS: Myofibroblasts are a reliable and simple indicator of fibrosis since they appear in early stages of PD treatment and in patients with minor morphologic anomalies. They are not exclusive of patients with sclerosing peritonitis, ultrafiltration loss or long standing treatment. Their absence in non-PD, uremic patients suggest that uremia-related fibrosis takes place without a significant participation of myofibroblasts.