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101.
A forensic Y-STR database generated in the US was compiled with profiles containing a portion or complete typing of 16 STR markers DYS19, DYS385, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS437, DYS438, DYS439, DYS456, DYS458, DYS635, DYS448, and Y GATA H4. There were 17,447 samples in the version of database in which 77% and 20% were collected in North America and Asia, respectively. The database was separated into six general populations, African American, Asian, Caucasian, Hispanic, Indian, and Native American. Each population was further classified into subgroups according to geographic regions. Some subgroups were tested, found to be homogenous and merged together. Allele and haplotype frequencies, as well as sample sizes were summarized. Of the full haplotypes (i.e., 16 STRs without missing data), 93.7% in total population were distinct, 92.9% were population specific, and 89.3% were only observed once. The majority of shared haplotypes were found among North American populations as a result of admixture lasting the past few hundred years. The power of discrimination (PD), coancestry coefficient (Fst), and coefficient of gene differentiation (Gst) at locus and haplotype levels were also calculated. The most polymorphic marker was DYS385; this marker contains a tandem duplication and actually is composed of two loci. Both Gst and Fst estimates were very small with haplotypes composed of a high number of STRs haplotypes (e.g., 10–16 markers), although Gst is slightly more conservative for these extended haplotypes. With Native American removed from the total population data set, the Gst and Fst estimates reduce further. PD was 0.9998 for the total population dataset for all 16 Y-STR markers. Three measures of Y-STR profile frequency were calculated: (1) unconditional haplotype frequency, (2) population substructure adjusted frequency, and (3) binomial upper bound of the haplotype frequency. The binomial upper bound is the most conservative estimate for most forensic applications. Estimates of the weight of a Y-STR haplotype can be estimated using population specific or total population databases.  相似文献   
102.
103.

Background

Major depressive disorder (MDD) is a multifactorial disease which often coexists with cognitive deficits. Depression-induced cognitive deficits are known to be associated with aberrant reward processing, neurochemical and structural alterations. Recent studies have shown that chronic electrical stimulation of brain reward areas induces a robust antidepressant effect. However, the effects of repeated electrical self-stimulation of lateral hypothalamus - medial forebrain bundle (LH-MFB) on depression-induced cognitive deficits and associated neurochemical and structural alterations in the prefrontal cortex (PFC) are unknown.

Objectives

We investigated the effect of chronic rewarding self-stimulation of LH-MFB in neonatal clomipramine (CLI) model of depression. During adulthood, neonatal CLI and saline administered rats were implanted with bilateral electrodes stereotaxically in the LH-MFB and trained to receive intracranial self-stimulation (ICSS) for 14 days. The rats were tested for depressive-like behaviors, learning and memory followed by estimation of PFC volumes, levels of monoamines and its metabolites in the PFC.

Results

We found that chronic ICSS of LH-MFB reverses CLI-induced behavioral despair and anhedonia. Interestingly, self-stimulation normalizes the impaired novel object and location recognition memory in CLI rats. The amelioration of learning impairments in CLI rats was associated with the reversal of volume loss and restoration of monoamine metabolism in the PFC.

Conclusion

We demonstrated that repeated intracranial self-stimulation of LH-MFB ameliorates CLI-induced learning deficits, reverses altered monoamine metabolism and the atrophy of PFC. Our results support the hypothesis that chronic brain stimulation rewarding experience might be evolved as a potential treatment strategy for reversal of learning deficits in depression and associated disorders.  相似文献   
104.

Background  

Differences in outcome between African-Caribbean and white British patients with psychosis may be due to perceived racism and a difficulty in trusting services seen as discriminatory.  相似文献   
105.
Estradiol-2/4-hydroxylase (E-2/4-H) activity was determined in the mouse uterus during early pregnancy as well as in ovarian steroid hormone-treated ovariectomized uterus. Under the assay conditions used, E-4-H was the predominant catechol estrogen-forming monooxygenase enzyme. The inhibition of E-4-H activity by SKF-525A, metyrapone and alpha-naphthoflavone suggested involvement of cytochrome P450-dependent monooxygenases. A haloestrogen, 2-fluoroestradiol (2-FL-E2), also inhibited this activity. During the peri-implantation period, no change in uterine E-4-H activity was noted on the morning of days 2 through 5, but the activity significantly (P less than 0.01) increased in the afternoon of day 4 of pregnancy. A single injection of estradiol-17 beta (E2, 100 ng/mouse) to ovariectomized mice significantly (P less than 0.01) elevated the level of E-4-H activity at 24 h as did injections of progesterone (P4, 2 mg/mouse) for 2 days. When 2 days of P4 (2 mg/mouse) treatment was combined with a single injection of E2 (20 ng/mouse), E-4-H activity increased 1.3-fold (P less than 0.05) by 24 h above that of P4 treatment alone. Dexamethasone (200 micrograms/mouse) and cholesterol (2 mg/mouse) treatment for 2 days had no effect on E-4-H activity. Thus, the stimulatory effect of P4 and E2 on E-4-H activity appeared to be specific. The increased activity of uterine E-4-H prior to implantation on day 4 evening and the modulation of its activity by P4 and/or E2 suggest an involvement of 4-hydroxyestradiol in embryo implantation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
106.
The gene of Listeria monocytogenes that encodes a major extracellular protein (p60) was cloned in Escherichia coli. The gene was designated iap, as p60 was previously shown to represent an invasion-associated protein (M. Kuhn and W. Goebel, Infect. Immun. 57:55-61, 1989). The recombinant E. coli clone expressed p60, as shown by immunoblotting. The complete nucleotide sequence of iap was determined. The deduced amino acid sequence of p60 (484 amino acids) contains a putative N-terminal signal sequence of 27 amino acids and an extended repeat region consisting of 19 threonine-asparagine units. Hybridization with the entire iap gene revealed the presence of homologous sequences in most other Listeria species. In contrast, a 400-base-pair internal iap probe which contained the whole repeat region hybridized only with genomic DNA from L. monocytogenes. Four oligonucleotides previously described as specific probes for the detection of L. monocytogenes (A. R. Datta, B. A. Wentz, D. Shook, and M. W. Trucksess, Appl. Environ. Microbiol. 54:2933-2937, 1988) were shown to be part of the iap gene.  相似文献   
107.
Upper and centralized body fat distribution is associated with non-insulin dependent diabetes mellitus (NIDDM). Few studies have focused on anthropometric characteristics of preadults from families in which there is a diabetic (NIDDM) proband. This study explores the prevalence of upper and centralized body fatness in Mexican American children from the Diabetes Alert study (1981–1983) in Starr County, Texas. Anthropometric data on 165 males and 224 females 9–19 years include measures of adiposity such as skinfold thicknesses and the body mass index (BMI), a measure of overweight. They show rates of obesity two to three times that of White children of comparable age and sex from National Health Surveys. In comparison with U.S. White subjects, Mexican American adults are shorter, have more adiposity and arm muscle mass and have sitting heights and body breadths at the mean of these dimensions for the U.S. population. Children from Diabetes Alert families show only marginal excess of severe obesity (> 95th percentile of BMI) when compared to the general population of children surveyed in Starr County schools. Girls from these families, but not boys, have excess fatness in the BMI compared to Mexican American children from the Hispanic Health and Nutrition Examination Survey (HHANES); suprailiac skinfold thicknesses are also greater in children of the Diabetes Alert study than in HHANES children. From 1972 through 1982, Mexican American children in South Texas showed an increase in average stature, weight, and the BMI. These data together suggest that excessive obesity exists and may be increasing in children in populations at risk for NIDDM. The prevention of NIDDM in the Mexican American population may be more effective if educational and promotional interventions include the school aged population. © 1993 Wiley-Liss, Inc.  相似文献   
108.
Objectives There are only a few studies on maternal morbidity, delivery complications and maternal mortality in Bangladesh. This study analyzes data from a follow-up study conducted by the Bangladesh Institute of Research for Health and Technologies (BIRPERHT) on maternal morbidity in rural Bangladesh in 1993. Methods A total of 1020 pregnant women were interviewed in the follow-up component of the study. The survey collected information on socioeconomic and demographic characteristics, pregnancy-related care and practice, morbidity during the period of follow-up as well as in the past, information concerning complications at the time of delivery and during the postpartum period. For the purpose of this study, we selected 993 pregnant women with at least one antenatal follow-up. Both bivariate and multivariate analyses were conducted to identify the potential risk factors for complication during delivery and duration of labor. Results and conclusions It appears that complications during the antenatal period can result in various complications at the time of delivery. Some of the important findings are: hemorrhage during the antenatal period increases the risk of excessive hemorrhage during delivery, the risk of obstructed labor increases significantly if abdominal pain is observed during the antenatal period, prolonged labor appears to be significantly higher for the first pregnancy, and pregnancies suffering from abdominal pain during pregnancy tend to have a higher risk of prolonged labor during delivery. The duration of labor appears to be negatively associated with the number of previous pregnancies, being longest for the first pregnancies. The duration of labor pain is significantly higher for the respondents who reported the index pregnancy as undesired, and, similarly, the respondents who were reported to be involved with gainful employment would have a shorter duration of labor pain than those having no involvement with gainful employment.  相似文献   
109.
Doctor patient communication is the most important and an integral part of any treatment regimen. Properly carried out it has been shown to have a therapeutic effect equivalent to drugs. Despite being so important part of treatment it is more than often taken and carried out casually. Apart from apathy towards this practice, its omission in the medical study curriculum is an important factor. This study was carried in amongst the surgical residents of surgical departments of various medical colleges to assess the attitude of surgical residents towards patient doctor communication. A questionnaire was forwarded by mail and email and the response was assessed: The responses of the surgical residents from various residents from different medical colleges were similar. Most of the residents prefer inclusion of communication skill in medical education curriculum  相似文献   
110.

Introduction

Within monocyte-derived macrophages, HIV-1 accumulates in intracellular virus-containing compartments (VCCs) that are inaccessible to the external environment, which implicate these cells as latently infected HIV-1 reservoirs. During mother-to-child transmission of HIV-1, human placental macrophages (Hofbauer cells (HCs)) are viral targets, and have been shown to be infected in vivo and sustain low levels of viral replication in vitro; however, the risk of in utero transmission is less than 7%. The role of these primary macrophages as viral reservoirs is largely undefined. The objective of this study is to define potential sites of viral assembly, accumulation and neutralization in HCs given the pivotal role of the placenta in preventing HIV-1 infection in the mother-infant dyad.

Methods

Term placentae from 20 HIV-1 seronegative women were obtained following caesarian section. VCCs were evaluated by 3D confocal and electron microscopy. Colocalization R values (Pearson''s correlation) were quantified with colocalization module of Volocity 5.2.1. Replication kinetics and neutralization studies were evaluated using p24 ELISA.

Results

We demonstrate that primary HCs assemble and sequester HIV-1BaL in intracellular VCCs, which are enriched in endosomal/lysosomal markers, including CD9, CD81, CD63 and LAMP-1. Following infection, we observed HIV-1 accumulation in potentially acidic compartments, which stained intensely with Lysotracker-Red. Remarkably, these compartments are readily accessible via the cell surface and can be targeted by exogenously applied small molecules and HIV-1-specific broadly neutralizing antibodies. In addition, broadly neutralizing antibodies (4E10 and VRC01) limited viral replication by HIV-1-infected HCs, which may be mediated by FcγRI.

Conclusions

These findings suggest that placental HCs possess intrinsic adaptations facilitating unique sequestration of HIV-1, and may serve as a protective viral reservoir to permit viral neutralization and/or antiretroviral drug entry in utero.  相似文献   
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