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21.
Turner's syndrome (TS) is associated with a wide spectrum of clinical features, such as short stature and gonadal dysgenesis. While it is a common chromosomal abnormality, the association of Turner's syndrome and hypopituitarism is an uncommon finding. We describe here a girl with concomitant pituitary insufficiency and gonadal dysgenesis. When she was 7 years old, her mother reported that she suffered from frontal headache, asthenia and delayed growth. Basal laboratory thyroid evaluation suggested hypothyroidism, with no evidence of autoimmune disease association. She began taking L-thyroxine. At age 11 years, short stature and complaints of frontal headache still persisted. She was still prepubertal and her bone age was delayed by 2.2 years. Her karyotype was compatible with 45,X/46,XX (100 cells analyzed by FISH) and a CT scan showed empty sella. At 12 years of age, an anterior pituitary stimulation test with insulin, gonadotropin-releasing hormone (GnRH) and thyrotropin-releasing hormone (TRH) showed gonadotropin, thyrotropin (TSH) and growth hormone (GH) deficiency. Replacement therapy with GH was begun and she grew 12 cm during the first year of treatment. This report illustrates that, despite the high incidence of sinusitis, short stature and primary hypothyroidism in TS, we should consider the presence of hypopituitarism when the patient presents low levels of TSH with negative thyroid antibodies and inappropriately low levels of gonadotropins for patients with gonadal dysgenesis.  相似文献   
22.
Abstract Background : The aim of the present study was to determine the prevalence, associated symptoms, and clinical outcomes of children with acute abdominal pain who had been admitted to an emergency department. Methods : Children aged between 2 and 16 years who presented to the emergency department of Cerrahpa?a Medical School, Istanbul University between July 2001 and August 2002 with acute abdominal pain were enrolled in this study. A questionnaire was completed each patient admitted to our pediatric emergency unit for acute abdominal pain. Data collected included presenting signs and symptoms, the hospital follow up for all children who returned within 10 days, test results, and telephone follow up. Results : The number of children referred to the emergency department was 7442, with 399 (5.4%) of these having acute abdominal pain. The mean age of the study population was 6.9 ± 3.5 years, and 201 of the patients were male. The five most prevalent diagnoses were: (i) upper respiratory tract infection and/or complicated with otitis media or sinusitis (23.7%); (ii) abdominal pain with uncertain etiology (15.4%); (iii) gastroenteritis (15.4%); (iv) constipation (9.4%); and (v) urinary tract infection (8%). The most common associated symptoms were decreased appetite, fever and emesis. Because of follow‐up deficiency the progress of 28 patients was not obtained. Eighty‐two children were referred to the department of pediatric surgery, but only 17 of 82 (20.7%) required surgical intervention (15 of these 17 for appendicitis). Eleven patients returned within 10 days for re‐evaluation, but the initial diagnosis was not changed. The complaints of 57 patients with uncertain etiology were resolved within 2 days. Conclusions : An acute complaint of abdominal pain was usually attributed to a self‐limited disease. However, the percentage of surgical etiology is not negligible.  相似文献   
23.
Objective: This study examined the effects of prenatal alcohol exposure (PAE) on the incidence and severity of neonatal abstinence syndrome (NAS).

Study design: For this pilot study, 70 pregnant women on opioid maintenance therapy (OMT) were recruited from a perinatal substance abuse clinic. Subjects were categorized into three study groups based on the timing of alcohol use during pregnancy as assessed by repeated self-reported measures and a comprehensive panel of ethanol biomarkers. NAS outcomes included: duration of hospital stay, the need for pharmacological treatment of NAS, newborn age at the initiation of NAS treatment, duration of treatment and cumulative methadone dose administered.

Results: The study included a large proportion of ethnic minorities (81.4% Hispanic, 5.7% American Indian), women with less than a high school education (52.2%) and unplanned pregnancy (82.9%). In multivariate analysis, PAE was not associated with NAS outcomes; however, one newborn diagnosed with fetal alcohol syndrome (FAS) demonstrated much more severe NAS compared to other PAE infants. Interestingly, 3rd trimester PAE was associated with a higher prevalence of microcephaly (62.5%) compared to the PAE abstaining group (36.8%; p?=?0.08).

Conclusion: In this study, PAE was not associated with NAS severity; however, further examination in a larger study is needed.  相似文献   
24.
In order to understand how West Nile virus (WNV) has evolved since its introduction into North America, we have studied the genetic and phenotypic variation among WNV isolates collected in various areas during consecutive transmission seasons. The present report describes for the first time phenotypic changes occurring in the North American WNV population. Several isolates collected in Texas during 2003 display a small plaque (sp) and temperature sensitive (ts) phenotype, as well as reduced replication in cell culture, in comparison to isolates collected in 2002 and New York in 1999. Studies of mouse neuroinvasiveness/neurovirulence also indicate that several of these isolates were attenuated in neuroinvasiveness, but not for neurovirulence. The complete genome and deduced amino acid sequences of several of these isolates have been determined in order to map the mutations responsible for this phenotypic variation. These data indicate microevolution of WNV and the emergence of isolates exhibiting phenotypic variation.  相似文献   
25.
Asthma is the most common chronic inflammatory disorder of the airways among children. It is a complex clinical disease characterized by airway obstruction, airway inflammation and airway hyperresponsiveness to a variety of stimuli. The development of allergic asthma exists of three phases, namely the induction phase, the early-phase asthmatic reaction (EAR) and the late-phase asthmatic reaction (LAR). Each phase is characterized by the production and interplay of various cell-derived mediators. In the induction phase, T helper cytokines are important in the development of asthma. Most important mediators in the EAR are preformed mediators, newly synthesized lipid mediators and cytokines that are produced by mast cells. During the LAR, inflammatory molecules are produced by various cell types, such as eosinophils, neutrophils, T cells, macrophages, dendritic cells, and structural cells. Chronical inflammation leads to structural changes of the airway architecture. In this review, the most important mediators involved in the induction phase, the early-phase and late-phase asthmatic reaction are discussed.  相似文献   
26.
BACKGROUND: Most HIV-infected subjects on antiretroviral therapy (ART) in resource-limited settings do not undergo virologic monitoring. There is an urgent need for cheap, accessible HIV RNA assays for early diagnosis of virologic failure. We investigated filter paper transfer (FPT) of whole blood and plasma as an alternative to standard plasma-based assays for virologic monitoring in Uganda. METHODS: Whole blood (n = 306) and plasma (n = 218) from 402 subjects established on ART were spotted onto filter paper and transported to Europe for HIV RNA extraction and quantification. These results were compared to a gold standard plasma assay in Kampala. RESULTS: Of 402 ART-treated subjects, 39 (9.7%) had viremia detectable (>500 copies/mL) by local methods. Plasma FPT showed excellent agreement with gold standard, whereas whole blood yielded a large number of false-positive viral loads. CONCLUSIONS: This is the first study to investigate the use of FPT in ART-treated subjects and demonstrates that it may provide a practical, reliable method for virologic monitoring in resource-poor settings. Plasma FPT was accurate but requires centrifuge; whole blood produced a high number of false-positive results, but these were low-level. Whole blood may be sufficiently accurate if higher HIV RNA cut-offs were used to define virologic failure.  相似文献   
27.
Vibrio cholerae 638 (El Tor, Ogawa), a new CTXΦ-negative hemagglutinin/protease-defective strain that is a cholera vaccine candidate, was examined for safety and immunogenicity in healthy adult volunteers. In a double-blind placebo-controlled study, no significant adverse reactions were observed in volunteers ingesting strain 638. Four volunteers of 42 who ingested strain 638 and 1 of 14 who received placebo experienced loose stools. The strain strongly colonized the human small bowel, as evidenced by its isolation from the stools of 37 of 42 volunteers. V. cholerae 638, at doses ranging from 4 × 107 to 2 × 109 vibrios, elicited significant serum vibriocidal antibody and anti-Ogawa immunoglobulin A antibody secreting cell responses.  相似文献   
28.

This study evaluated, for the first time, the genetic diversity of Toxoplasma gondii isolates from free-range chickens from the state of Paraíba, Northeast Brazil. Tissue samples from 33 chickens from properties in five municipalities of Paraíba (Esperança, Olho d’Água, Malta, Monteiro, and Patos) were bioassayed in mice. The brains of mice infected with T. gondii cysts were used for DNA extraction and genotyping. Genotyping was performed using 11 PCR-RFLP markers and 15 microsatellite (MS) markers. Complete genotyping results were obtained for 29 isolates, with nine genotypes detected by RFLP and 15 genotypes identified by MS. Three genotypes (#273, #274, and #277) have only been recently identified from pigs in the region. Brazilian clonal types BrII and BrIII were identified from one isolate each. Clonal types I, II, and III were not detected by RFLP. Genotype #13 (Caribbean 1), detected in 48.3% (14/29) of isolates from four of the five municipalities investigated, was the most prevalent genotype in the state of Paraíba. However, the MS analysis showed that of these 14 isolates, only four were unique genotypes, and considering the distance between the municipalities from where they were collected, it is possible that only seven are independent isolates while the others are clones. The other genotypes were restricted to different microregions. The results indicate that the Caribbean 1 lineage of T. gondii is circulating widely in Northeast Brazil. The genotypic diversity of T. gondii in the state of Paraíba is high, and microsatellite analysis revealed this diversity with higher resolution than PCR-RFLP.

  相似文献   
29.
Background: Glutathione S-transferases (GSTs) are drug-metabolising enzymes involved in biotransformation of carcinogens, drugs, xenobiotics and oxygen free radicals. Polymorphisms of GST genes contribute to inter-individual and population variability in the susceptibility to environmental risk factors, cancer predisposition and pharmacotherapy responses. However, data about GST variability in Argentina are lacking.

Aim: The purpose was to determine the prevalence of GSTM1, GSTT1 and GSTP1 polymorphisms in the general population from a central region of Argentina and to perform inter-population comparisons.

Subjects and methods: GSTM1 and GSTT1 gene deletions and GSTP1 c.313A?>?G were genotyped by PCR assays in 609 healthy and unrelated Argentinians.

Results: The frequencies of variant genotypes in Argentinians were GSTM1-null (45%), GSTT1-null (17%) and GSTP1-GG (11%). GSTM1-present genotype was significantly associated with GSTP1-AG or GSTP1-GG variants (p?=?0.037; p?=?0.034, respectively). Comparison with worldwide populations demonstrated that the GST distributions in Argentina are similar to those reported for Italy and Spain, whereas significant differences were observed regarding Asian and African populations (p?Conclusion: This study has determined, for the first time, the normative profile of three pharmacogenetically relevant polymorphisms (GSTM1, GSTT1 and GSTP1) in the largest Argentinian cohort described to date, providing the basis for further epidemiological and pharmacogenetic studies in this country.  相似文献   
30.
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