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731.

Background and purpose:

The histamine H4 receptor is widely expressed in cells of immune origin and has been shown to play a role in a variety of inflammatory processes mediated by histamine. In this report, we describe the in vitro and in vivo anti-inflammatory properties of a potent histamine H4 receptor antagonist, A-940894 (4-piperazin-1-yl-6,7-dihydro-5H-benzo[6,7]cyclohepta[1,2-d]pyrimidin-2-ylamine).

Experimental approach:

We have analysed the pharmacological profile of A-940894 at mouse native, rat recombinant and human recombinant and native, histamine H4 receptors by radioligand binding, calcium mobilization, mast cell shape change, eosinophil chemotaxis assays and in the mouse model of zymosan-induced peritonitis.

Key results:

A-940894 potently binds to both human and rat histamine H4 receptors and exhibits considerably lower affinity for the human histamine H1, H2 or H3 receptors. It potently blocked histamine-evoked calcium mobilization in the fluorometric imaging plate reader assays and inhibited histamine-induced shape change of mouse bone marrow-derived mast cells and chemotaxis of human eosinophils in vitro. In a mouse mast cell-dependent model of zymosan-induced peritonitis, A-940894 significantly blocked neutrophil influx and reduced intraperitoneal prostaglandin D2 levels. Finally, A-940894 has good pharmacokinetic properties, including half-life and oral bioavailability in rats and mice.

Conclusions and Implications:

These data suggest that A-940894 is a potent and selective histamine H4 receptor antagonist with pharmacokinetic properties suitable for long-term in vivo testing and could serve as a useful tool for the further characterization of histamine H4 receptor pharmacology.  相似文献   
732.
Objective: The aim of this study is to assess the correlation between traditional cardiovascular risk factors and elevated plasma tHcy level in Nigerian hypertensive. Methods: Thirty-six hypertensive patients were recruited with 36 age and sex-matched controls. The age, sex and anthropometric measurements including height, weight and body mass index (BMI) were taken. Plasma total cholesterol, low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), triglycerides and tHcy were analyzed. The results of the two groups were compared. Results: The mean total cholesterol and LDL- C were significantly higher in the subjects than in the controls (P = 0.01 and 0.03 respectively). On the other hand, means of HDL-C and triglycerides were not significantly different between the two groups (P =0.06 and 0.68 respectively). Mean total plasma tHcy was ( 12.95 ±4.9) μmol/L in hypertensive patients when compared with ( 11.29 ±3.6) μmol/L in the controls (P = 0.09) , however the mean tHcy was significantly higher in hypertensive patients who had stroke or myocardial infarction than those without these complications (one way Anova F = 3.63, P = 0.04). Significant positive correlation was seen between tHcy and systolic blood pressure, diastolic blood pressure, BMI and LDL-C. Conclusion : The study suggests that elevated plasma tHcy may predict occurrence of cardiovascular complications in hypertensive individuals.  相似文献   
733.
Oral Diseases (2011) 17 , 258–264 Objective: To analyse and compare the expression of Palate, Lung, and Nasal Epithelium Clone (PLUNC) proteins in salivary glands from patients with and without AIDS (control group) using autopsy material. Methods: We analysed the expression of PLUNCs using immunohistochemistry in parotid (n = 45), submandibular (n = 47) and sublingual gland (n = 37) samples of AIDS patients [30 with normal histology, 21 with mycobacteriosis, 14 with cytomegalovirus (CMV) infection, 30 with chronic non‐specific sialadenitis, and 30 HIV‐negative controls. In situ hybridization (ISH) for SPLUNC 2 in the HIV‐negative group was performed. Results: SPLUNC 1 expression was detected in the mucous acini of submandibular and sublingual glands, and SPLUNC 2 were seen in the serous cells. LPLUNC 1 expression was only positive in the salivary ducts. There was a higher expression of SPLUNC 2 in AIDS patients with CMV infection and mycobacteriosis when compared with all other groups. The intensity of staining for SPLUNC 2 was greater around the lesions than the peripheral ones. ISH for SPLUNC 2 showed perinuclear positivity in the serous cells in all HIV‐negative cases. Conclusions: SPLUNC 1 and LPLUNC 1 proteins were similarly expressed in the salivary glands of AIDS patients and non‐HIV patients. CMV infection and mycobacteriosis increase SPLUNC 2 expression in serous cells in the salivary gland of AIDS patients.  相似文献   
734.

Introduction  

Extracorporeal membrane oxygenation (ECMO) is a supportive cardiopulmonary bypass technique for babies with acute reversible cardiorespiratory failure. We assessed morbidity in ECMO survivors at the age of five years, when they start primary school and major decisions for their school careers must be made.  相似文献   
735.
Aim:  To report the stability of parent-perceived child irregular eating from 6 months to 14 years of age and to investigate a predictive model inclusive of child and parent factors.
Methods:  Of the 7223 singleton children in a birth cohort, 5122 children were re-interviewed at 5 years and 4554 for the 14-year analysis. Information was obtained from structured interviews including questions answered by parents of the child at birth, 6 months, 5 years and 14 years; and by teenagers at age 14 years and from physical measures of the child. The mother's perception that the child was an irregular eater at age 14 years was the major outcome variable of interest.
Results:  Approximately 40% of irregular eaters at age 5 will still be irregular eaters at age 14 years. This was not related to maternal education or socio-economic class. Significant at multivariate analysis were infant feeding problems and the children's ability to regulate their sleep and mood. Significant maternal factors were greater age, not feeling positive about the baby and persistent maternal anxiety during the child's early years.
Conclusion:  Irregular eating behaviour displays considerable continuity from childhood to mid-adolescence. Independent contributions to this behavioural phenotype include child biological and psychological factors and maternal anxiety during the child's early years.  相似文献   
736.
A simple co-culture bioassay system was used to investigate whether or not the anatomical origin affected the ability of epithelial cells from the human uterine (Fallopian) tube to 'bind' spermatozoa. This study was also used to identify some of the factors which may be involved in the regulation of sperm-epithelial interactions in vitro by comparing different tissue culture models and assessing the effect of oestradiol concentration. Epithelial explants harvested from different regions of human uterine tubes were co-incubated with a known concentration of motile donor spermatozoa. All results were adjusted to reflect a standard sperm concentration of 5 x 10(6)/ml. More spermatozoa associated per field of isthmic compared to ampullary epithelium [isthmus 9.5 +/- 0.9, ampulla 7.1 +/- 0.7 (mean +/- SEM); n = 36, P < 0.05, ANOVA] and cells from post-menopausal patients had an apparently reduced ability to bind spermatozoa [isthmus 5.5 +/- 2.0, ampulla 4.3 +/- 1.4 (mean +/- SEM); n = 4]. Neither menstrual cycle stage nor addition of mid-cycle concentrations of 17beta-oestradiol (750 pmol/l) affected the number of spermatozoa which bound to epithelium from either tubal region. In addition, the number of spermatozoa which bound per field of polarized explants was greater (P < 0.05) than that bound to dissociated primary and passaged epithelial cell monolayers. This report is the first to provide evidence suggestive of a role for sperm- epithelial binding in the formation of an isthmic sperm reservoir in the human uterine tube. Results also indicate that oestrogen is not involved in the regulation of these interactions, and that cell polarity is an important factor for such associations in vitro.   相似文献   
737.

Background

Perception of midline diastema differs among individuals and cultures. To some, it is a feature of beauty, while to others it is aesthetically appalling. From a scientific point of view, midline diastema is a deviation from normal adult dentition. It is not uncommon among some African natives to find individuals demanding for artificially created midline diastema from dental practitioners.

Objective

To present a rare case of pulpal necrosis involving maxillary and mandibular central incisors as a result of poorly executed teeth modification in a bid to create upper and lower midline diastemata.

Result

A 23-year old lady presented with history of spontaneous, sharp, persistent pain associated with palatal swelling and discharging sinus of two weeks duration in relation to maxillary central incisors (11, 21). The complaint was preceded by a history of recurrent pain in relation to 11, 21, 31 and 41 which started soon after obtaining artificially created maxillary and mandibular midline diastemata from a dental quack. Periapical x-ray revealed periapical radiolucency in relation to 21 and 41. Vitality test confirmed necrotic pulp in the lower central incisors. The affected teeth were scheduled for root canal therapy (RCT) and porcelain fused to metal crown. The RCT of 11 and 21 had been completed but further treatment stalled due to financial constraint.

Conclusion

This is a case of obsession for midline diastema, poor dental health education, and illegal dental practice.  相似文献   
738.
BACKGROUND: The study aimed to determine whether allergic conditions accompany analgesic intolerance. METHODS: A total of 132 analgesic-intolerant patients with bronchial asthma admitted to the adult allergy unit from January 1991 to October 1997 and 103 patients with bronchial asthma randomly selected from among the asthmatics referred to our department between January and October 1997 were enrolled in the study. Those having analgesic intolerance and bronchial asthma were accepted as group I; patients having only asthma were accepted as group II. A standard questionnaire was completed for all the patients. Physical examination, routine skin prick tests, determination of total IgE levels and blood type, and oral analgesic provocation tests were also performed. RESULTS: The results showed that some allergic conditions were significantly more common in group I (22.7% and 7.8% for food allergy/intolerance [P<0.05], 16.7% and 7.8% for antibiotic allergy, 16.7% and 2.9% for dermographism, 9.8% and 1.0% for metal allergy, and 9.1% and 1.0% for chronic urticaria for groups I and II, respectively [P<0.001]). In addition, the mean of the total IgE level in the serum was higher in group I than group II (77.6 and 53.7 IU/ml; P<0.05), and the cumulative analgesic consumption was more in group I (14.2+/-17.1 and 9.1+/-12.5 boxes; P<0.05). CONCLUSIONS: Dermographism; chronic urticaria; antibiotic, metal, and food allergy; high levels of total IgE; and a high amount of cumulative analgesic consumption may be the conditions accompanying analgesic intolerance in asthmatics.  相似文献   
739.
We have shown recently that adenosine deaminase (ADA)-deficient mice die perinatally with severe liver cell degeneration. In addition to enzyme substitution, we report the restoration of viability through introduction of the human ADA gene. The ADA gene is subject to complex developmental and tissue-specific regulation. To include the cis- regulatory elements necessary for correct regulation of the human ADA gene, a large transgenic locus constituting the human ADA gene with 10 kb of 5' and 4 kb of 3' flanking sequences was generated by co- injection of two overlapping DNA fragments into murine zygotes. Probably as a result of extrachromosomal (homologous) recombination between the fragments, one of the two transgenic lines contained a reconstituted, functional human ADA gene. As in man, human ADA expression generally was low in these transgenic mice, but high in the thymus, spleen and gastro-duodenal part of the gut. Apparently, all cis- regulatory elements essential for a human expression pattern were incorporated in the transgene and were functional in the murine background. Similarly to man, the upper alimentary tract of the transgenic mice revealed low human ADA activity in contrast to extremely high levels of murine ADA. The human gene probably lacks the cis-regulatory elements that target high level murine ADA expression to the murine upper alimentary tract. ADA-deficient mice rescued by introduction of the human ADA transgene appeared histologically and immunologically normal. Apparently, human ADA can complement murine ADA in all tissues, even in the epithelium of the upper alimentary tract where human ADA activity is as much as 70-fold lower than murine ADA activity in wild-type mice. Clearly, the lethal phenotype of ADA- deficient mice is due to the absence of ADA.   相似文献   
740.
质量保证(QA)和质量控制(QC)是所有实验室进行检测分析的基础。与其他医学学科相比,研究者最近才认识到男科实验室需要有QA和QC。此外,有证据表明,一些医生并不完全赞成尚需进行QA和QC的努力。然而,由于QA和QC是质量管理实施过程的中心环节,评审机构和监管部门越来越需要实验室制定有效的QA和QC措施。随着《世界卫生组织人类精液分析实验室技术手册》第5版的出版,该手册推荐的实验方法学已有相应的修改,现行的QA和QC体系也需作出一定程度的更新,以适应新的变化和要求。主要讨论该手册在3方面的变化,即:①建议根据精液质量推测体积。②精子活力等级由原来的4级改为3级。③将精子形态的参考值下限定为4%(95%CI为3%。4%)。还讨论了QC及QA在所有男科实验室检测中的重要性,包括即将开展的评估精子DNA完整性的实验。同时,阐述对从事男科学检验工作人员开展充分的初级培训与专业继续教育的必要性。  相似文献   
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