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81.
To understand the mechanism(s) of appetite modulation by DHEA, we have undertaken a series of studies to examine the effects of DHEA on neurotransmitters and neuropeptides known to affect appetitive behavior. Here, we report the effect of DHEA on serum enterostatin-VPDPR or E, a pentapeptide known to cause selective diminution in fat intake. Four-week-old lean (fa/+) and obese (fa/fa) Zucker rats were divided into control and treatment groups. DHEA-treated groups received powdered chow containing 0.6% DHEA ad lib for 16 weeks. Another group of obese rats was pair fed to match the intake of the obese DHEA-treated rats. At the end of this period, trunk blood was collected from fasted rats for assay of E-like immunoreactivity (E-LI) by ELISA. DHEA treatment caused a significant diminution in circulating E-LI in both lean (control: 2030 +/- 226; treated: 752 +/- 145 ng/mL; n = 10, p < 0.0001) and obese (control: 2489 +/- 391, n = 6; treated: 1123 +/- 185 ng/mL, n = 7; p = 0.0003) rats. Because DHEA treatment decreases caloric intake and body weight, we examined the effect of caloric intake and body weight on E-LI levels. Serum ELI levels were lower in the obese DHEA-treated group compared to that of obese pair fed (pair fed: 1589 +/- 313, n = 6; DHEA: 1123 +/- 185 ng/mL, n = 7), but the differences were statistically insignificant (p = 0.185). Also, both weight-matched lean and obese control rats had significantly (p < 0.008) higher E-LI than their DHEA-treated counterparts. To examine whether the decrease in serum E-LI following DHEA treatment could be due to increased peptide metabolism, the rate of disappearance of endogenous E-LI from serum (obese control and DHEA-treated) at 37 degrees C was evaluated. The results show an attenuation of peptide metabolism in serum from DHEA-treated rats, a finding contrary to our expectations. In summary, DHEA treatment lowers serum E-LI levels both in lean and obese Zucker rats. This decrement in peptide level is not secondary to changes in body weight or caloric intake due to DHEA, or due to altered serum peptide metabolism. Although DHEA appears to be a potent modulator of E-LI levels, the relationship between DHEA and E-LI in relation to appetitive behavior remains to be clarified. 相似文献
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85.
Susceptibility pattern and molecular type of species-specific Candida in oropharyngeal lesions of Indian human immunodeficiency virus-positive patients 下载免费PDF全文
Lattif AA Banerjee U Prasad R Biswas A Wig N Sharma N Haque A Gupta N Baquer NZ Mukhopadhyay G 《Journal of clinical microbiology》2004,42(3):1260-1262
A study of oropharyngeal candidiasis (OPC) in Indian human immunodeficiency virus (HIV)/AIDS patients was conducted over a period of 15 months. This study revealed that 75% of the HIV/AIDS patients had OPC. MIC testing revealed that 5% of the Candida isolates were fluconazole resistant. A correlation between CD4(+)-T-cell counts and development of OPC in HIV/AIDS patients was also observed. Molecular typing of C. albicans isolates showed that all were genetically unrelated. 相似文献
86.
Isolated primary amyloid tumor of bone is rare; however, preoperative diagnosis can be rewarding because the prognosis is excellent. There are no clinical or roentgenographic criteria that can establish this diagnosis. There are few previous reports of fine-needle aspiration (FNA) where diagnosis of amyloidoma was made retrospectively. They describe the presence of extracellular hyaline material along with plasma cells and lymphocytes. A 35-year-old female was referred to the FNA clinic with swelling in the right upper chest wall. Radiologic findings revealed a destructive lytic lesion involving the bodies of D1 and D2 vertebrae with extension into surrounding soft tissue. Repeated FNA smears were hypocellular but had abundant homogeneous flocculent material, which stained positive with Congo red. A few plasma cells and foreign-body giant cells were also seen. We conclude that preoperative FNA cytology diagnosis of amyloid tumor is possible. Hypocellular smears with flocculent material, plasma cells, and foreign-body giant cells in absence of granulation tissue should suggest the diagnosis. 相似文献
87.
Relationship between the expression of various markers and prognostic factors in breast cancer 总被引:5,自引:0,他引:5
Anim JT John B Abdulsathar S SA Prasad A Saji T Akhtar N Ali V Al-Saleh M 《Acta histochemica》2005,107(2):87-93
The immunohistochemical detection of six markers of breast cancer has been compared in the present study with known prognostic factors of the disease to establish locally a standard panel of markers for the management of breast cancer. Sections of tissue of 114 consecutive breast cancer cases were studied immunohistochemically, using antibodies against oestrogen receptor (ER), progesterone receptor (PR), androgen receptor, c-erbB2, cathepsin D, and cyclin D. Marker labelling was graded as recommended in the literature. Using the chi(2)-test, relationships were determined between marker labelling and histological type of cancer, tumour grade, tumour size, axillary lymph node status and age of patient. A p value below 0.05 was considered significant. A positive relationship was found between ER and PR and lower grades of cancer, and a negative relationship was found with medullary and atypical medullary carcinoma. The four other markers showed no relationship with grade or type of cancer. All markers showed no significant relationship with size of tumour, presence of axillary node metastasis or age of patient. There was positive correlation between c-erbB2 and cathepsin D. Our study confirms the association between ER and PR and histological type and grade of breast cancer, both known parameters of good prognosis. We found no consistent relationship between the other four markers and prognostic factors studied, other than the suggestion that c-erbB2 and cathepsin D may be useful markers for poor prognosis and can be usefully applied locally, especially in the light of the current availability of trastuzumab (Herceptin) for management of c-erbB2-positive cases. We found no relationship between the markers and tumour size, axillary lymph node status or age. 相似文献
88.
X-linked agammaglobulinemia (XLA) is an immunodeficiency caused by mutations in the Bruton tyrosine kinase (BTK) gene. Twenty Australian patients with an XLA phenotype, from 15 unrelated families, were found to have 14 mutations. Five of the mutations were previously described c.83G>A (p.R28H), c.862C>T (p.R288W), c.904G>A (p.R302G), c.1535T>C (p.L512P), c.700C>T (p.Q234X), while nine novel mutations were identified: four missense c.82C>A (p.R28S), c.494G>A (p.C165Y), c.464G>A (p.C155Y), c.1750G>A (p.G584E), one deletion c.142_144delAGAAGA (p.R48_G50del), and four splice site mutations c.241-2A>G, c.839+4A>G, c.1350-2A>G, c.1566+1G>A. Carrier analysis was performed in 10 mothers and 11 female relatives. The results of this study further support the notion that molecular genetic testing represents an important tool for definitive and early diagnosis of XLA and may allow accurate carrier status and prenatal diagnosis. 相似文献
89.
Vinod Dasa James R.B. Eastwood Michal Podgorski Heewon Park Christopher Blackstock Tetyana Antoshchenko Piotr Rogala Tadeusz Bieganski S. Michal Jazwinski Malwina Czarny‐Ratajczak 《American journal of medical genetics. Part A》2019,179(4):534-541
Mutations in the COMP, COL9A1, COL9A2, COL9A3, MATN3, and SLC26A2 genes cause approximately 70% of multiple epiphyseal dysplasia (MED) cases. The genetic changes involved in the etiology of the remaining cases are still unknown, suggesting that other genes contribute to MED development. Our goal was to identify a mutation causing an autosomal dominant form of MED in a large multigenerational family. Initially, we excluded all genes known to be associated with autosomal dominant MED by using microsatellite and SNP markers. Follow‐up with whole‐exome sequencing analysis revealed a mutation c.2032G>A (p.Gly678Arg) in the COL2A1 gene (NCBI Reference Sequence: NM_001844.4), which co‐segregated with the disease phenotype in this family, manifested by severe hip dysplasia and osteoarthritis. One of the affected family members had a double‐layered patella, which is frequently seen in patients with autosomal recessive MED caused by DTDST mutations and sporadically in the dominant form of MED caused by COL9A2 defect. 相似文献
90.
Immune regulation by novel costimulatory molecules 总被引:10,自引:0,他引:10
CD4 helper T (Th)-cells and the cytokines that they produce play essential regulatory roles in immune and autoimmune responses.
Th activation and differentiation is regulated by costimulatory receptors. CD28 and CTLA-4 are important in maintaining the
threshold of T-cell activation. ICOS and PD-1 are novel costimulatory receptors expressed on activated T-cells. B7-H3 recognizes
a putative costimulatory receptor on activated T-cells. Here we summarize the latest developments in the novel costimulatory
molecules and their roles in regulating Th activation, differentiation, and function. 相似文献