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51.
Mandibular pseudocarcinomatous hyperplasia   总被引:5,自引:0,他引:5  
AIMS: Three unusual cases of pseudocarcinomatous (pseudoepitheliomatous) hyperplasia (PH) affecting chronic osteomyelitic mandibular sequestra are reported to highlight the differences with the various squamous neoplasms which occur in that site. METHODS AND RESULTS: In two patients carrying a mandibular graft following the excision of an ameloblastoma, mucosal ulcers resulted in chronic osteomyelitis. In a third patient, an apical dental infection was associated with fistulated osteomyelitis. Histology of the three sequestra showed an intraosseous squamous proliferation. It was characterized by a peripheral involvement of medullary spaces, the more mature epithelial layer covering the bone trabeculae without intervening stroma, and the basal type epithelial layer surrounding a central fibrovascular core. There were no histological or cytological signs of malignancy. CONCLUSION: PH shows an inverted pattern when compared with the centro-medullary tumoural islands seen in the various oral or odontogenic squamous neoplasms which occur in the jaws. The lack of signs of malignancy distinguish PH from common squamous cell carcinomas. A short clinical course is an important feature in the distinction of PH from the well differentiated squamous cell carcinomas which may develop in fistulated chronic osteomyelitis.  相似文献   
52.
Height is a highly heritable and classic polygenic trait. Recent genome-wide association studies (GWAS) have revealed that at least 180 genetic variants influence adult height. However, these variants explain only about 10% of the phenotypic variation in height. Genetic analysis of short individuals can lead to the discovery of novel rare gene defects with a large effect on growth. In an effort to identify novel genes associated with short stature, genome-wide analysis for copy number variants (CNVs), using single-nucleotide polymorphism arrays, in 162 patients (149 families) with short stature was performed. Segregation analysis was performed if possible, and genes in CNVs were compared with information from GWAS, gene expression in rodents'' growth plates and published information. CNVs were detected in 40 families. In six families, a known cause of short stature was found (SHOX deletion or duplication, IGF1R deletion), in two combined with a de novo potentially pathogenic CNV. Thirty-three families had one or more potentially pathogenic CNVs (n=40). In 24 of these families, segregation analysis could be performed, identifying three de novo CNVs and nine CNVs segregating with short stature. Four were located near loci associated with height in GWAS (ADAMTS17, TULP4, PRKG2/BMP3 and PAPPA). Besides six CNVs known to be causative for short stature, 40 CNVs with possible pathogenicity were identified. Segregation studies and bioinformatics analysis suggested various potential candidate genes.  相似文献   
53.

Background

In November 2006, an email-based health promotion program for pregnant women was implemented nationally in the Netherlands. The program consisted of emails containing quizzes with pregnancy-related questions tailored to the number of weeks of pregnancy. Emails were sent out once every 4 weeks, up to a maximum of nine emails.

Objectives

The aims of the study were (1) to assess the recruitment of participants and their representativeness of the Dutch population and (2) to study differences in recruitment, program use, and program appreciation among women with different levels of education.

Methods

Data from 13,946 pregnant women who enrolled during the first year of the program were included. Upon registration, participants were asked how they found out about the program and subsequently received an email questionnaire to assess demographic, lifestyle, and Internet characteristics. Program use was tracked, and participants were classified into five user groups (inactive to very active). Program appreciation (low, intermediate, and high) was assessed twice with an email questionnaire that was sent after the woman had received her third and sixth quiz email. Information about pregnant women and their characteristics was obtained from Dutch registries to assess representativeness of the study population.

Results

About 8% of the pregnant women in the Netherlands enrolled in the program. Immigrants were underrepresented, and women with a low level of education seemed to be slightly underrepresented. Most women knew about the program from a promotional email sent by the organization (32%), followed by the Internet (22%) and midwives (16%). Women with little education were more often inactive users of the program than were highly educated women (15% vs 11%, P < .001), whereas highly educated women were more often very active users compared with women with little education (25% vs 20%, P< .001). However, women with less education were more likely than women with more education to have a high appreciation of the program after receiving three quiz emails (52% vs 44%, P = .001).

Conclusions

In this real-life setting, pregnant women can be reached through an email-based health promotion program. Selective engagement by education level remains a challenge.  相似文献   
54.
Recently, a hexanucleotide (GGGGCC) repeat expansion in the first intron of C9ORF72 was reported as the cause of chromosome 9p21‐linked frontotemporal dementia‐amyotrophic lateral sclerosis (FTD‐ALS). We here report the prevalence of the expansion in a hospital‐based cohort and associated clinical features indicating a wider clinical spectrum of C9ORF72 disease than previously described. We studied 280 patients previously screened for mutations in genes involved in early onset autosomal dominant inherited dementia disorders. A repeat‐primed polymerase chain reaction amplification assay was used to identify pathogenic GGGGCC expansions. As a potential modifier, confirmed cases were further investigated for abnormal CAG expansions in ATXN2. A pathogenic GGGGCC expansion was identified in a total of 14 probands. Three of these presented with atypical clinical features and were previously diagnosed with clinical olivopontocerebellar degeneration (OPCD), atypical Parkinsonian syndrome (APS) and a corticobasal syndrome (CBS). Further, the pathogenic expansion was identified in six FTD patients, four patients with FTD‐ALS and one ALS patient. All confirmed cases had normal ATXN2 repeat sizes. Our study widens the clinical spectrum of C9ORF72related disease and confirms the hexanucleotide expansion as a prevalent cause of FTD‐ALS disorders. There was no indication of a modifying effect of the ATXN2 gene.  相似文献   
55.
Menstrual cycle and appetite control: implications for weight regulation   总被引:1,自引:0,他引:1  
Hormonal fluctuations associated with the menstrual cycle influence appetite control and eating behaviour. Energy intake varies during the reproductive cycle in humans and animals, with a periovulatory nadir and a luteal phase peak. Patterns of macronutrient selection show less consistency but a number of studies report carbohydrate cravings in the premenstrual phase, particularly in women with premenstrual syndrome. The cyclical nature of food cravings are frequently, but not invariably, associated with depression. Fluctuations in appetite, cravings and energy intake during the menstrual cycle may occur in parallel with cyclical rhythms in serotonin, which can be accompanied by affective symptoms. The premenstrual phase can be considered as a time when women are especially vulnerable to overconsumption, food craving and depression; this is often associated with low serotonin activity.   相似文献   
56.
Hydrosalpinges adversely affect markers of endometrial receptivity   总被引:22,自引:10,他引:22  
While in-vitro fertilization (IVF) was initially developed in women with tubal factor infertility, recent clinical studies have suggested that the presence of hydrosalpinges lowers implantation and pregnancy rates. We postulated that these hydrosalpinges cause impaired endometrial receptivity. A total of 103 women with hydrosalpinges were prospectively evaluated, and compared with 55 infertile and 44 fertile controls. All women had endometrial biopsies during the window of implantation, analysed by conventional histological criteria, and also stained for three integrin markers of endometrial receptivity (alpha1beta1, alpha4beta1 and alpha vbeta3). Women with hydrosalpinges (cases) expressed significantly less of the alpha vbeta3 integrin compared with controls. There was no difference in expression of alpha1beta1 or alpha4beta1 among groups. A significantly greater number of cases had out of phase histology and missing alpha vbeta3 (type I defects) and absent integrin expression despite normal histological maturation (type II) defects, compared with controls. Of 20 women with impaired endometrial receptivity who were also biopsied after hydrosalpinx surgery, 70% demonstrated increased alpha vbeta3 expression. Seventy-seven percent of type I and 57% of type II defects were corrected postoperatively. Using markers of endometrial receptivity, this study demonstrates that inflammatory hydrosalpinges have an adverse effect on endometrial receptivity, which in some cases may be overcome by surgical treatment of the hydrosalpinx.   相似文献   
57.
T cell cytokine expression may be induced by the cytokine IL-2 or via the TCR complex. The comparative effects of cytokine- and TCR-mediated signalling on the induction of human IL-5 mRNA were examined. Cytokine mRNA expression was analysed by RT-PCR in fresh peripheral blood mononuclear cells (PBMC) from normal individuals and in populations of activated T lymphocytes, derived from phytohaemagglutinin (PHA)- stimulated PBMC. rIL-2 induced IL-5 expression in PBMC, the kinetics of which were similar to the effects of PHA. rIL-4 induced IL-5 mRNA expression in activated T lymphocytes. IL-5 expression induced by either IL-2 or PHA was completely abolished by the protein synthesis inhibitor cycloheximide. rIL-2-induced IL-5 expression was resistant to cyclosporin A (CsA), whereas IL-5 expression elicited by PHA was inhibited by CsA, at doses as low as 10 ng/ml. Rapamycin (RAP) had no effect on rIL-2-stimulated IL-5 expression, but suppressed IL-5 expression induced by PHA. The inhibitory effect of RAP on PHA-induced IL-5 expression was more apparent at 12 and 24 h after stimulation than at earlier times. The resistance of IL-2 receptor (IL-2R) signalling to CsA and RAP indicates that the IL-2R and the TCR are associated with different pathways regulating IL-5 expression.   相似文献   
58.
Superoxide, an agent which attenuates the half-life of nitric oxide, is metabolized and synthesized by superoxide dismutase (SOD) and xanthine oxidase, respectively. Over the last few years much work has focused on the role of nitric oxide in human parturition. The aim of this study was to determine whether the onset of human parturition is associated with a change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD), manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the uterus. Samples of myometrium, placenta, decidua and fetal membranes were obtained from women before and after the onset of labour at term. Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like immunoreactivity was detected in syncytiotrophoblast cells, villous stromal cells and endothelial cells of blood vessels in the placenta. In the myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial cells and to some vascular smooth muscle cells. In the fetal membranes we observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion, extravillous trophoblast and decidua. There was no difference in SOD enzyme activity or staining intensity for SOD between different cell types before and during labour. Xanthine oxidase immunoreactivity was identified in each of the tissues examined and again there was no difference in immunostaining in tissues obtained from women delivered before or after the onset of labour. These results show that the pregnant uterus is capable of both synthesizing and degrading superoxide and suggest that superoxide dismutase and xanthine oxidase may play a role in the maintenance of uterine quiescence during pregnancy, but not in the initiation of parturition.   相似文献   
59.
Aim: To describe gut colonization in preterm infants using standard culture and 16S gene rRNA profiling, exploring differences in healthy infants and those who developed NEC/late onset sepsis (LOS). Methods: Ninety‐nine stools from 38 infants of median 27‐week gestation were cultured; 44 stools from 27 infants had their microbial profiles determined by 16S. Ordination analyses explored effects of patient variables on gut communities. Results: Standard microbiological culture identified a mean of two organisms (range 0–7), DGGE 12 (range 3–18) per patient. Enterococcus faecalis and coagulase negative staphylococci (CONS) were most common by culture (40% and 39% of specimens). Meconium was not sterile. No fungi were cultured. Bacterial community structures in infants with NEC and LOS differed from healthy infants. Infants who developed NEC carried more CONS (45% vs 30%) and less Enterococcus faecalis (31% vs 57%). 16S identified Enterobacter and Staphylococcus presence associated with NEC/LOS, respectively. Conclusions: Important differences were found in the gut microbiota of preterm infants who develop NEC/LOS. The relationship of these changes to current practices in neonatal intensive care requires further exploration.  相似文献   
60.
The aim of this study is to examine relationships of sleep duration with sociodemographic and health‐related factors, psychiatric disorders and sleep disturbances in a nationwide sample in Korea. A total of 6510 subjects aged 18–64 years participated in this study. Logistic regression was used to calculate the odd ratios and 95% confidence intervals of the covariates, psychiatric disorders and sleep disturbances across the following sleep duration categories: 5 h or less, 6, 7, 8 and 9 h or more per day. Low levels of education, unemployment and physical illness were associated with sleeping for 5 h or less and 9 h or more. Being older and widowed/divorced/separated, high levels of physical activity, pain/discomfort, obesity and high scores on the General Health Questionnaires were associated with sleeping for 5 h or less. Female, being younger and underweight were associated with sleeping for 9 h or more. Alcohol dependence, anxiety disorder and social phobia were associated significantly with sleeping for 5 h or less and 9 h or more. Other psychiatric disorders were more common in subjects who slept for 5 h or less (e.g. alcohol use disorder, mood disorder, major depressive disorder, dysthymic disorder, obsessive‐compulsive disorder and specific phobia) or 9 h or more (e.g. post‐traumatic stress disorder). In addition, subjects who slept for 5 h or less reported more sleep disturbances than did subjects who slept for 7 h. Short or long sleep is associated with psychiatric disorders and/or sleep disturbance, therefore attention to the mental health of short or long sleepers is needed.  相似文献   
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