Substituting human chorionic gonadotropin by gonadotropin-releasing hormone agonist to trigger final follicular maturation, during controlled ovarian hyperstimulation, results in less systemic inflammation.

BACKGROUND: To investigate the degree of systemic inflammation, as reflected by serum C-reactive protein (CRP) levels, associated with controlled ovarian hyperstimulation (COH) with human chorionic gonadotropin (hCG) or gonadotropin-releasing hormone (GnRH) agonist for the induction of final follicular maturation. DESIGN: Prospective, observational study. SETTING: An in vitro fertilization (IVF) unit of an academic medical center. PATIENTS: Twenty-four women undergoing COH and IVF with the flexible GnRH antagonist protocol were prospectively assigned to receive hCG or GnRH agonist for the induction of final follicular maturation. METHODS: Blood was drawn three times during COH for measurement of sex-steroid and CRP levels: the day on which adequate suppression was obtained (Day-0); the day of or prior to administration of hCG (Day-hCG); and (3) the day of ovum pick-up (Day-OPU). Levels were compared among the three time points in the two groups. RESULTS: No between-group differences were observed in terms of patient age, gonadotropin dosage, duration of stimulation or number of oocytes retrieved. Serum CRP levels were significantly higher on Day-OPU than on Day-hCG and Day-0, but the difference was significant only in the hCG group (p<0.03 for both). The percentage change in CRP levels after hCG administration (Day-OPU vs. Day-hCG) (96%) was higher than that after GnRH administration (23%). CONCLUSION: Administration of GnRH agonist in patients undergoing COH for IVF yields a lesser degree of systemic inflammation, as reflected by CRP levels, than hCG.     

Plasma levels of neuropeptides in Alzheimer's disease.

BACKGROUND: In the central nervous system, several neuropeptides are believed to be involved in the pathophysiology of Alzheimer's disease (AD). Indeed, previous studies have documented that glucagon-like peptide 1 (GLP-1) possesses neurotropic properties and can reduce amyloid-beta peptide levels in the brain in vivo. Moreover, the concentrations of neuropeptide Y (NPY) seem to be altered in the cerebrospinal fluid of patients with AD and in subjects with major depression. Finally, among the modifications induced by aging, a dysregulation of the ghrelin-growth hormone (GH) system has been reported. METHODS: We investigated the plasma concentrations of these neuropeptides in 14 subjects with AD. Data obtained from these patients were compared with data from an age- and weight-matched healthy group. RESULTS: No significant differences were found between the two groups in relation to plasma levels of GLP-1, NPY, ghrelin and GH. Peripheral NPY concentrations were positively correlated with ghrelin levels in both groups, and with plasma GLP-1 concentration only in controls. CONCLUSION: On the basis of our results, peripheral levels of these neuropeptides seem not to serve as biochemical markers of AD.     

Gonadotropin-releasing hormone antagonists increase follicular fluid insulin-like growth factor-I and vascular endothelial growth factor during ovarian stimulation cycles.

The aim of the present study was to investigate the effect of gonadotropin-releasing hormone (GnRH) antagonists (GnRH-ant) on follicular fluid (FF) insulin-like growth factor-I (IGF-I) and FF vascular endothelial growth factor (VEGF) levels. Sixty women undergoing assisted reproduction were randomized and assigned to two different GnRH analog regimens: GnRH agonist (GnRH-a) and GnRH-ant. FF VEGF and FF IGF-I concentrations were significantly increased in the patients treated with GnRH-ant (p < 0.001). In the same patients we observed a statistically significant reduction in serum luteinizing hormone (LH) and estradiol (E2) levels (p < 0.001 and p < 0.05, respectively), FF E2 and FF androstenedione levels (p < 0.05 and p < 0.001, respectively), as well as a reduction in the number of pregnancies although this was not statistically significant. In the GnRH-ant group, FF VEGF levels were positively correlated with FF IGF-I levels, and both were negatively correlated with serum LH levels. The increase in FF IGF-I and FF VEGF levels in women treated with GnRH-ant could be explained by a deleterious follicular environment in response to profound suppression of LH and E2 levels.     

Endopeptidase activities of selected Porphyromonas spp., Prevotella spp. and Fusobacterium spp. of oral and non-oral origin

The ability of three Porphyromonas spp., seven Prevotella spp., seven Fusobacterium spp. and two related Bacteroides spp. (B. levii and B. macacae) to degrade an extensive range of synthetic endo-, amino- and diamino peptidase substrates linked to the fluorescent leaving group 7-amido-4-methylcoumarin (NHMec) was investigated. Many more species than was previously recognized exhibited peptidase activities, albeit at lower levels than those already described for Porphyromonas gingivalis. Detection of chymotrypsin-like activity was dependent on which of three NHMec-linked substrates was used, but all species exhibited degradative activity with at least one of these substrates. Elastase-like activity was detected in all species though not all species reacted with each of the elastase substrates. Glycylprolyl peptidase activity was detected in all of the species tested with the exception of F. mortiferum, F. gonidiaformans, F. naviforme and F. necrophorum. While the detection of peptidase activities does not appear to be useful for the differentiation of species within the genera Bacteroides and Prevotella, its ability to differentiate species of the genus Porphyromonas or Fosobacterium further investigation.     

Influence of age on the reactivity of the BANA test among Brazilian children.

Three hundred and twenty samples of subgingival plaque were obtained from 80 caucasian girls, ranging from 10 to 13 years of age. The samples were analyzed to verify the influence of age upon colonization of the gingival sulcus by microorganisms potentially pathogenic to the periodontal tissues. The gingival and plaque status were evaluated through the gingival index (GI) and plaque index (PlI) and the microflora was assessed by the enzymatic method benzoyl-arginine-naphthylamide (BANA). The results of the BANA test were positive for 62.50% of the tested individuals and 40% of the examined sites. The influence of age was statistically significant on BANA reactivity, and the number of positive sites was greater at 11 (57.5%) than at 12 years (28.8%).     

Guillain-Barré syndrome in South-West Stockholm, 1973–1991, 3. Clinicoepidemiological subgroups

Using hierarchical cluster analysis, applied to 47 cases of Guillain-Barre Syndrome (GBS) incident in South-West Stockholm (SWS) during the period from January 1973 to June 1992, we identified three major clinicoepidemiological subgroups. The first subgroup, 25.5% of the cases (26.7 ± 6.7 years), recorded a peak incidence at ages 20–29 years and presented significant differences from other subgroups, a high proportion of cases with onset at low age preceded by respiratory infection (83.3%) and with normal motor conduction velocity (50.0%). Also found, were less affected biological parameters, a rapidly progressive course and independence in gait at one month after onset. A second subgroup, 27.7% of cases, was severely affected, clinically and functionally. It consisted predominantly of young individuals (22.7 ± 11.1 years), with a high incidence (69.2% of cases) in autumn. A third subgroup, comprising 40.47; of cases, was older (61.1 ± 11.0 years) and, in general, also severely affected. The incidence of this form appeared to be invariant with time.     

A chemically defined medium for the culture of mature oligodendrocytes

A new chemically defined medium consisting of equal parts of Dulbecco modified Eagle's and Ham's F-12 media supplemented with insulin, sodium selenite, putrescine, and D+ galactose, which allows the long-term survival of mature oligodendrocyte pure cultures, is described. Immunohistochemical staining has shown that over 90% of the cells become positive for myelin proteins shortly following subculture. Contaminating astrocytes (2%) do not survive in this medium. Biochemical data have indicated that these purified oligodendrocytes express 2'3'-cyclic nucleotide 3'-phosphohydrolase and UDP-galactose ceramide galactosyltransferase activities. Electron microscopical examination revealed that the oligodendrocytes were mostly of medium-dark type and appeared to be identical to cells cultured in serum-containing medium. The ability to maintain pure oligodendrocyte cultures in such a defined medium will allow investigations concerning exogenous and endogenous factors involved in oligodendrocyte metabolism.     

Protein-calorie malnutrition impairs host defense against Candida albicans.

Protein-calorie malnutrition (PCM) impairs immune responsiveness predisposing to Candida albicans sepsis, but mechanisms are unclear. This study examined the effect of PCM on enteric-derived C. albicans intestinal translocation and the ability of in vivo interferon-gamma (IFN-gamma) to upregulate macrophage (MO) candidacidal mechanisms in PCM mice. Control (24% casein) and low protein (2.5%) diets were given for 4 weeks. Mice (n = 160) were fed C. albicans in their drinking water for 3 days and C. albicans translocation (mean colony-forming units (CFU)/g tissue +/- SEM) to the GI tract, liver, spleen, and kidney was assessed at 1 and 5 days following endotoxin challenge of 1, 5, and 10 mg/kg body wt. In a separate study (n = 100 mice), IFN-gamma (1000-10,000 U/day ip) vs saline was given for 3 days prior to harvesting peritoneal macrophages for assay of superoxide anion (O2-), percentage macrophage phagocytosis of C. albicans, and percentage killing of C. albicans. On Day 1, fungal translocation to the intestinal wall and systemic organs in the PCM group was significantly higher. On Day 5, mean CFU were significantly higher in the PCM group, indicating impaired organ clearance. Mean O2-, phagocytosis, and killing were significantly impaired in the PCM group (P less than 0.05), but IFN-gamma improved all functions. PCM significantly depressed host responses to C. albicans. IFN-gamma treatment enhanced candidacidal mechanisms, suggesting a therapeutic role in the malnourished host predisposed to C. albicans sepsis.     

The effect of sodium fluoride on trabecular architecture.

The effect of sodium fluoride therapy on iliac trabecular bone has been studied in 15 patients with primary osteoporosis by comparing bone biopsies taken before and after two years of treatment. A marked increase in bone volume (43%) was observed, which was attributable to an increase in trabecular thickness (46%) rather than their number. Because the trabecular bone surface, the trabecular number, the bone volume/trabecular width ratio, and the trabecular terminus number do not change significantly after fluoride treatment, we conclude that fluoride does not induce the de novo generation of trabeculae, nor does it restore trabecular connectivity despite the restoration of bone mass. These data suggest that the restoration of skeletal mass with fluoride may not lead to a comparable decrease in the risk of future fracture.     

Time-dependent effects of ovarian steroids on tyrosine hydroxylase activity in the limbic forebrain of female rats

Summary In this work, we have studied the time-course of the effects of pharmacological administration of ovarian steroids on tyrosine hydroxylase (TH) activity in the limbic forebrain of ovariectomized rats. Administration of estradiol produced a late decrease in TH activity. This effect was found 24 hours after the last steroid injection, disappearing at 32 hours. It was antagonized by progesterone, since a single injection of this steroid to estradiol-pretreated rats reversed to control values the estradiol-induced decrease. Nevertheless, the administration of progesterone after estradiol treatment caused a short-time decrease in the limbic activity of TH, which was observed 4 hours after the last steroid injection, disappearing subsequently. On the other hand, the administration of progesterone alone produced a biphasic effect, with a reduction at 24 hours, followed by an increase at 32 hours. These effects were only observed in the animals non-treated with estradiol, disappearing with a previous treatment with estrogens. Hence, it can be concluded that both ovarian steroids may affect the limbic TH activity. Thus, estradiol produced a late inhibitory effect on the activity of this enzyme, which was antagonized by progesterone. Administration of the last one to estradiol-treated rats produced a short-time inhibitory effect, whereas its administration to non-treated rats produced a late biphasic effect (inhibition followed by stimulation), which was not observed in estradiol-treated rats.