Huntingtin-associated protein 1 (HAP1) interacts with the p150Glued subunit of dynactin

Huntington's disease (HD) is an inherited neurodegenerative disease caused by expansion of a polyglutamine repeat in the HD protein huntingtin. Huntingtin's localization within the cell includes an association with cytoskeletal elements and vesicles. We previously identified a protein (HAP1) which binds to huntingtin in a glutamine repeat length-dependent manner. We now report that HAP1 interacts with cytoskeletal proteins, namely the p150 Glued subunit of dynactin and the pericentriolar protein PCM-1. Structural predictions indicate that both HAP1 and the interacting proteins have a high probability of forming coiled coils. We examined the interaction of HAP1 with p150 Glued . Binding of HAP1 to p150 Glued (amino acids 879-1150) was confirmed in vitro by binding of p150 Glued to a HAP1-GST fusion protein immobilized on glutathione-Sepharose beads. Also, HAP1 co-immunoprecipitated with p150 Glued from brain extracts, indicating that the interaction occurs in vivo . Like HAP1, p150 Glued is highly expressed in neurons in brain and both proteins are enriched in a nerve terminal vesicle-rich fraction. Double label immunofluorescence experiments in NGF-treated PC12 cells using confocal microscopy revealed that HAP1 and p150 Glued partially co-localize. These results suggest that HAP1 might function as an adaptor protein using coiled coils to mediate interactions among cytoskeletal, vesicular and motor proteins. Thus, HAP1 and huntingtin may play a role in vesicle trafficking within the cell and disruption of this function could contribute to the neuronal dysfunction and death seen in HD.     

Development of the enkephalin-, neurotensin- and somatostatin-like (ENSLI) amacrine cells in the chicken retina

The development of the enkephalin-, neurotensin- and somatostatin-like immunoreactive (ENSLI) amacrine cells in the chicken retina has been investigated by radioimmunoassay (RIA) and immunocytochemistry (ICC). By RIA, enkephalin-like immunoreactivity (ENK-LI) was detected at embryonic day (E) 5 at only very low levels, which gradually increased until E17. From E18 to E21, there was a relatively rapid increase in ENK-LI levels, and just after hatching, there was a very steep rise. By ICC, the cell bodies of the ENSLI amacrine cells were first detected in the inner nuclear layer on E18, with no immunostaining in the inner plexiform layer (IPL). On E21, more cells were detected and processes in the IPL were visible, but detailed arborisations were not clear. On postnatal day (P) 1, the ENSLI amacrine cells showed a morphology similar to that in mature retina in both the density of cell bodies and the ramification pattern of processes. Antibodies to neurotensin and somatostatin revealed a similar developmental pattern. Thus, the three peptides appear to follow a similar developmental pattern in the ENSLI amacrine cells, suggesting that the three peptides respond similarly to developmental stimuli, just as they are released in parallel in response to physiological stimulation from mature ENSLI amacrine cells. After hatching, higher levels of ENK-LI were detected by RIA and more ENSLI amacrine cell bodies and processes were detected by ICC in animals kept in the light than in those kept in the dark. In retinas kept in the light for 12 h, it was found that immunoreactive processes in the IPL formed strongly stained patches, but this was not observed in retinas kept in the dark for 12 h.     

The effects of varying dietary n-6 to n-3 fatty acid ratios on platelet reactivity, coagulation screening assays, and antithrombin III activity in dogs

Thirty beagles were placed on diets containing ratios of n-6 to n-3 fatty acids ranging from 5:1 to 100:1 for 12 weeks to determine the effects of these diets on platelet reactivity, coagulation screening assays, and antithrombin III activity. Although small changes were observed in adenosine diphosphate (ADP)-, collagen-, and arachidonic acid-induced platelet aggregation and 14C-serotonin release, fibrinogen concentrations, and antithrombin III activities during the 12-week study, these changes were not of clinical significance and did not correlate with the varying ratios of n-6 to n-3 fatty acids.     

Perceptual learning of spatial localization: specificity for orientation, position, and context

Discrimination of simple visual attributes can improve significantly with practice. We have trained human observers to perform peripherally presented tasks involving the localization of short line segments and examined the specificity of the learning for the visual location, orientation, and geometric arrangement of the trained stimulus. Several weeks of training resulted in dramatic threshold reductions. The learning was specific for the orientation and location of the trained stimulus, indicating the involvement of the earliest cortical stages in the visual pathway where the orientation and location of stimuli are mapped with highest resolution. Furthermore, improvement was also specific for both the configuration of the trained stimulus and the attribute of the stimulus that was under scrutiny during training. This degree of specificity suggests that the learning cannot be achieved by cortical recruitment alone, as proposed in current models, but is likely to involve a refinement of lateral interactions within the cortex and possibly a gating of lower level changes by attentional mechanisms.     

Pre-labour rupture of membrane: the histological study of membrane and bacteriological profile

One hundred two (102) cases of pre-labour rupture of membrane (PROM) were studied and special attention was given to the histological study of the amniotic membrane as well as to the bacteriological study of high vaginal flora, cervical flora and flora of amniotic fluid, in search of probable causes or factors leading to PROM. The incidence was found to be 3.16% in the age group of 20-25 years without any relation to parity; and the duration of gestation was 38 to 40 weeks in most of the cases. The histological study revealed: (a) Focally denuded amniotic epithelium, focally separated amniotic epithelium from chorion layer, lesser density of focal squamoid change of the epithelium and thicker chorion layer probably indicating focal immaturity of the chorio-amnion, (b) lesser thickness of collagen layer, focal hydropic degeneration and mild cellular infiltrate, (c) presence of focal hyaline degeneration and focal calcification of chorio-amnion. Microbial culture revealed: (a) Higher rate of positive culture in high vaginal swab, cervical swab and amniotic fluid showing presence predominantly of Esch coli, Strept haemolyticus, klebseilla species, Staph aureus, Strept non-haemolyticus, proteus species and pseudomonas species against that of positive cultures in the control cases, (b) no anaerobic bacteria from high vaginal swab, cervical swab or from amniotic fluid. It was presumed that focal immaturity of chorio-amnion or focal irregularity in the chorio-amnion at the microscopical level, focal degeneration of collagen superadded with bacterial infection, however mild, could be the factors leading to weakness in the tensile strength of chorio-amnion, again leading to PROM, in the face of stress factors of foetal origin.     

The insulin resistance syndrome in native Hawaiians. Native Hawaiian Health Research (NHHR) Project

OBJECTIVE: To investigate whether fasting hyperinsulinemia is associated with a clustering of cardiovascular disease (CVD) risk factors, manifesting as the insulin resistance syndrome (IRS), in a population of native Hawaiians. RESEARCH DESIGN AND METHODS: A total of 574 native Hawaiians > or = 30 years of age were examined for blood pressure, waist-to-hip ratio (WHR), BMI, oral glucose tolerance, and fasting lipid, insulin, and C-peptide concentrations. All statistical analyses (n = 384) excluded 190 individuals who had NIDDM or who were taking hypertension medication. Using logistic regression analysis, fasting insulin and C-peptide levels were compared with CVD risk factors (glucose intolerance, hypertension, central adiposity, elevated triglyceride levels, and low HDL cholesterol levels) after adjusting for age and obesity. RESULTS: Sixty-six percent of native Hawaiians were overweight or obese, and 70% were found to have central adiposity. Fasting insulin concentrations were correlated with BMI, WHR, blood pressure, and triglyceride, HDL cholesterol, and glucose concentrations. Fasting insulin was also significantly associated with an increasing number of CVD risk factors in each participant (P < 0.001). Fasting insulin and C-peptide concentrations were independently associated with glucose intolerance, high triglyceride levels, and low HDL cholesterol levels. However, only fasting C-peptide concentrations were independently associated with hypertension and central adiposity. Apparent differences in the correlates of fasting insulin and C-peptide may be related to multiple factors and warrant further evaluation. CONCLUSIONS: This study provides cross-sectional data confirming the existence of the IRS in native Hawaiians. However, further longitudinal studies are needed to examine the relationship of insulin resistance and/or surrogate markers to increased rates of NIDDM and CVD mortality in native Hawaiians.     

Are supplementary services provided during methadone maintenance really cost-effective?

OBJECTIVE: Previous research has suggested that support services supplementing methadone maintenance programs vary in their cost-effectiveness. This study examined the cost-effectiveness of varying levels of supplementary support services to determine whether the relative cost-effectiveness of alternative levels of support is sustained over time. METHOD: A group of 100 methadone-maintained opiate users were randomly assigned to three treatment groups receiving different levels of support services during a 24-week clinical trial. One group received methadone treatment with a minimum of counseling, the second received methadone plus more intensive counseling, and the third received methadone plus enhanced counseling, medical, and psychosocial services. The results at the end of the trial period have been published elsewhere. This article reports the results of an analysis at a 6-month follow-up. RESULTS: The follow-up analysis reaffirmed the preliminary findings that the methadone plus counseling level provided the most cost-effective implementation of the treatment program. At 12 months, the annual cost per abstinent client was $16,485, $9,804, and $11,818 for the low, intermediate, and high levels of support, respectively. Abstinence rates were highest, but modestly so, for the group receiving the high-intensity, high-cost methadone with enhanced services intervention. CONCLUSIONS: This study suggests that large amounts of support to methadone-maintained clients are not cost-effective, but it also demonstrates that moderate amounts of support are better than minimal amounts. As funding for these programs is reduced, these findings suggest a floor below which supplementary support should not fall.     

Modification of the Clinical Global Impressions (CGI) Scale for use in bipolar illness (BP): the CGI-BP

The Clinical Global Impressions Scale (CGI) was modified specifically for use in assessing global illness severity and change in patients with bipolar disorder. Criticisms of the original CGI were addressed by correcting inconsistencies in scaling, identifying time frames for comparison, clarifying definitions of illness severity and change, and separating out assessment of treatment side effects from illness improvement during treatment. A Detailed User's Guide was developed to train clinicians in the use of the new CGI-Bipolar Version (CGI-BP) for rating severity of manic and depressive episodes and the degree of change from the immediately preceding phase and from the worst phase of illness. The revised scale and manual provide a focused set of instructions to facilitate the reliability of these ratings of mania, depression, and overall bipolar illness during treatment of an acute episode or in longer-term illness prophylaxis. Interrater reliability of the scale was demonstrated in preliminary analyses. Thus, the modified CGI-BP is anticipated to be more useful than the original CGI in studies of bipolar disorder.     

The use of multiple antigenic peptide (MAP) in the immunodiagnosis of human immunodeficiency virus infection

In order to develop an ELISA system for the antibody detection of HIV-1 or HIV-2 infections, MAPs for HIV-1 gp41(584-618) and HIV-2 gp36(574-602) corresponding to the immunodominant regions of HIV-1 gp41 and HIV-2 gp36 were used as coating antigens in the ELISA. The MAPs were synthesized by the solid phase method using Fmoc-Lys(Fmoc)-OH and their molecular weights were confirmed by tricine gel electrophoresis. The MAPs reacted with all HIV positive sera (64 samples), but did not react with HIV negative sera (48 samples) obtained from healthy blood donors. The MAPs showed high sensitivity and specificity in anti-HIV 1/2 combo panel and anti-HIV-1 seroconversion panels. The results indicated that the ELISA system using synthetic MAPs of gp41(584-618) and gp36(574-602) as coating antigens can be used as an analytical system for the immunodiagnosis of HIV-1 or HIV-2 infections.     

Leptin is present in human milk and is related to maternal plasma leptin concentration and adiposity

Leptin is elevated during pregnancy and may be involved in the regulation of milk production in women. Immunoreactive leptin was quantified in human milk by modified radioimmunoassay. Leptin concentration was higher in whole vs. skim milk fractions; however, leptin concentration was not correlated with percentage milk fat. Leptin concentrations in whole and skim milk were correlated with maternal plasma leptin concentrations, maternal body weight, body mass index, and tricep skinfold thickness, but not with plasma insulin concentration. These data provide the first evidence for the presence of leptin in human milk in the range of concentrations found in human plasma and indicate that the concentration of leptin in milk reflects maternal adiposity. Determining the biological role(s) of milk-borne leptin could add to our understanding of neonatal metabolism and the mechanisms underlying the development of body fat and obesity in humans.