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1.
Background: The Centers for Disease Control and Prevention is incorporating laboratory data into real-time surveillance systems. When normal patterns of laboratory test orders and results are modeled, aberrations can be detected. Because many test orders are available electronically well before results, atypical patterns of test ordering may signal outbreaks.
Objectives: The authors sought to characterize baseline patterns in the ordering and early results of lumbar punctures, motivated by the possibility of using these data for real-time surveillance for early detection of meningitis or encephalitis outbreaks.
Methods: Retrospective cohorts of pediatric emergency department patients at a single hospital (1993–2003) and from the National Hospital and Ambulatory Medical Care Survey (1992–2000) were used for analysis.
Results: Test ordering exhibits seasonal patterns, with monthly peaks in January and August (p < 0.0001). For the hospital cohort, the rate of cerebrospinal fluid pleocytosis exhibits seasonal patterns (p < 0.0001), with a peak from August to October. This is strongly associated with the rate and pattern of clinical neurologic disease (p < 0.0001). A long-term secular decline in daily test ordering is evident, dropping from 5.3 to 2.9 in the hospital sample, and from 371.8 to 185.3 in the national sample (p < 0.001). The long-term rate of pleocytosis has declined (p < 0.0001), though the yield of testing for pleocytosis has improved (p = 0.0104).
Conclusions: Laboratory test patterns correspond with those of clinical disease and are a promising source of surveillance data. Using such data for real-time monitoring requires specific adjustments for patient age, periodicities, and secular trends.  相似文献   
2.
Hereditary hearing loss (HHL) is a very common disorder. When inherited in an autosomal recessive manner, it typically presents as an isolated finding. Interestingly and unexpectedly, in spite of extreme heterogeneity, mutations in one gene, GJB2, are the most common cause of congenital severe-to-profound deafness in many different populations. In this study, we assessed the contributions made by GJB2 mutations and chromosome 13 g.1777179_2085947del (the deletion more commonly known as del (GJB6-D13S1830) that includes a portion of GJB6 and is hereafter called Delta(GJB6-D13S1830)) to the autosomal recessive non-syndromic deafness (ARNSD) genetic load in Iran. Probands from 664 different nuclear families were investigated. GJB2-related deafness was found in 111 families (16.7%). The carrier frequency of the 35delG mutation showed a geographic variation that is supported by studies in neighboring countries. Delta(GJB6-D13S1830) was not found. Our prevalence data for GJB2-related deafness reveal a geographic pattern that mirrors the south-to-north European gradient and supports a founder effect in southeastern Europe.  相似文献   
3.

Background

Adenosine kinase deficiency is a recently described defect affecting methionine metabolism with a severe clinical phenotype comprising mainly neurological and hepatic impairment and dysmorphism.

Methods

Clinical data of 11 additional patients from eight families with adenosine kinase deficiency were gathered through a retrospective questionnaire. Two liver biopsies of one patient were systematically evaluated.

Results

The main clinical symptoms are mild to severe liver dysfunction with neonatal onset, muscular hypotonia, global developmental retardation and dysmorphism (especially frontal bossing). Hepatic involvement is not a constant finding. Most patients have epilepsy and recurrent hypoglycemia due to hyperinsulinism. Major biochemical findings are intermittent hypermethioninemia, increased S-adenosylmethionine and S-adenosylhomocysteine in plasma and increased adenosine in urine. S-adenosylmethionine and S-adenosylhomocysteine are the most reliable biochemical markers. The major histological finding was pronounced microvesicular hepatic steatosis. Therapeutic trials with a methionine restricted diet indicate a potential beneficial effect on biochemical and clinical parameters in four patients and hyperinsulinism was responsive to diazoxide in two patients.

Conclusion

Adenosine kinase deficiency is a severe inborn error at the cross-road of methionine and adenosine metabolism that mainly causes dysmorphism, brain and liver symptoms, but also recurrent hypoglycemia. The clinical phenotype varies from an exclusively neurological to a multi-organ manifestation. Methionine-restricted diet should be considered as a therapeutic option.
  相似文献   
4.

Background and aims

Children with first complex febrile seizure (CFS) are often admitted for observation. The goals of this study were 1) to assess the risk of seizure recurrence during admission, 2) to determine whether early EEG affects acute management.

Design/methods

We retrospectively reviewed a cohort of children 6–60 months of age admitted from a Pediatric Emergency Department for first CFS over a 15 year period. We excluded children admitted for supportive care of their febrile illness. Data extraction included age, gender, seizure features, laboratory and imaging studies, EEG, further seizures during admission, and antiepileptic drugs (AEDs) given.

Results

One hundred eighty three children met inclusion criteria. Seven patients had seizures during the admission (7/183 or 3.8%) Since 38 children were loaded with anti-epileptic medication during their visit, the adjusted rate is 7/145 or 4.8.Increased risk of seizure recurrence during admission was observed in children presenting with multiple seizures (P = 0.005).EEG was performed in 104/183 children (57%) and led to change in management in one patient (1%, 95% C.I. 0.05–6%). Six of the 7 children with seizure had an EEG. The study was normal in 3 and findings in the other 2 did not suggest/predict further seizures during the admission.

Conclusions

Children with first CFSs are at low risk for seizure recurrence during admission. Multiple seizures at presentation are associated with risk of early recurrence and may warrant an admission. EEG had limited effect on acute management and should not be an indication for admission.  相似文献   
5.

Background

Currant jelly stool is a late manifestation of intussusception and is rarely seen in clinical practice. Other forms of GI bleeding have not been thoroughly studied and little is known about their respective diagnostic values.

Objective

To assess the predictive value of GI bleeding (positive guaiac test, bloody stool and rectal bleeding in evaluation of intussusception.

Methods

We performed a retrospective cross-sectional study cohort of all children, ages 1 month-6 years of age, who had an abdominal ultrasound obtained evaluating for intussusception over 5 year period. We identified intussusception if diagnosed by ultrasound, air-contrast enema or surgery. Univariate and a multivariate logistic regression analysis were performed.

Results

During the study period 1258 cases met the study criteria; median age was 1.7 years (IQR 0.8, 2.9) and 37% were females. Overall 176 children had intussusception; 153 (87%) were ileo-colic and 23 were ileo-ileal. Univariate risk ratio and adjusted Odds ratio were 1.3 (95% CI, 0.8, 2.0) and 1.3 (0.7, 2.4) for positive guaiac test, 1.1 (0.6, 2.1) and 0.9 (0.3, 3.0) for bloody stool, and 1.7 (1.02, 2.8) and 1.3 (0.5, 3.1) for rectal bleeding .

Conclusion

Blood in stool, whether visible or tested by guaiac test has poor diagnostic performance in the evaluation of intussusception and is not independently predictive of intussusception. If the sole purpose of a rectal exam in these patients is for guaiac testing it should be reconsidered.  相似文献   
6.
Thalassemias are the most common hereditary diseases in Iran, resulting from synthesis defects in one or more hemoglobin (Hb) subunits. The majority of patients suffer from beta-thalassemia (thal), but cases with microcytic hypochromic anemia and normal electrophoretic patterns are suspected to have alpha- or silent beta-thal. A family from the northern part of Iran, an area highly prevalent for thalassemias, was referred to us for prenatal diagnosis. The hematological data of the father indicated a pattern of beta-thal minor. Reverse hybridization analysis for the most common beta-globin mutations identified IVS-II-1 (G-->A) in the heterozygous state. The maternal laboratory data indicated a case more compatible with alpha-thal. Iron deficient anemia was ruled out, and common alpha-thal point mutations and deletions were investigated. As no mutation was detected, chain synthesis was performed and showed an alpha/beta chain ratio of 2.1, that was in the range of beta-thal minor. DNA sequencing of the entire beta-globin gene identified a heterozygous GTG-->GGG (Val-->Gly) mutation at codon 126, also known as Hb Dhonburi (Neapolis). Prenatal diagnosis of the fetal DNA showed the absence of the IVS-II-1 and codon 126 anomalies. This result demonstrates the importance of screening of individuals with mild microcytic hypochromic anemia for both alpha- and silent beta-thal mutations.  相似文献   
7.
A gap exists in knowledge and the observed frequency with which patients with diabetes actually receive treatment for optimal cardiovascular risk reduction. Many interventions to improve quality of care have been targeted at the health systems level and provider organizations. Changes in several domains of care and investment in quality by organizational leaders are needed to make long-lasting improvements. In the studies reviewed, the most effective strategies often have multiple components, whereas the use of one single strategy, such as reminders only or an educational intervention, is less effective. More studies are needed to examine the effect of several care management strategies simultaneously, such as use of clinical information systems, provider financial incentives, and organizational model on processes of care and outcomes.  相似文献   
8.
This study aimed to assess the morphological changes in neonate vitrified testicular grafts after host treatment with melatonin. Neonate vitrified testes, candidates for transplantation to treated and nontreated groups receiving melatonin, were thawed in media containing or not containing 100 μm melatonin. Following transplantation, melatonin (20 mg kg?1 per day) and saline were given to the treated and nontreated groups for up to 9 weeks. The testicular status was assayed by terminal deoxynucleotidyl transferase (TdT)‐mediated deoxyuridine triphosphate (dUTP)‐biotin nick‐end labelling TUNEL, semi‐thin section and ultra‐structure studies. Chi‐squared test was used to compare categorical variables between the groups. Overall, the degenerative and apoptosis changes in the vitrified testis parenchyma were not significant. However, atrophic seminiferous cords and jumbled appearance of the interstitial space were more often observed in the nontreated group than in the treated ones. Semi‐thin sections showed that the germinal epithelium was taken in a normal arrangement on the testicular grafts of both groups. Nevertheless, ultrastructural analysis revealed that the characteristics of interstitial space cells, basement membrane BM and epithelial cells of seminiferous tubules in the treated group were better than those in the nontreated group. The study revealed a beneficial effect of melatonin on vitrified neonatal testes and after that, on restoring testicular grafts.  相似文献   
9.
Given the important aspects of wound healing approaches, in this work, an innovative biocompatible nanobiocomposite scaffold was designed and prepared based on cross-linked lignin–agarose hydrogel, extracted silk fibroin solution, and zinc chromite (ZnCr2O4) nanoparticles. Considering the cell viability technique, red blood cell hemolysis in addition to anti-biofilm assays, it was determined that after three days, the toxicity of the cross-linked lignin–agarose/SF/ZnCr2O4 nanobiocomposite was less than 13%. Moreover, the small hemolytic effect (1.67%) and high level of prevention in forming a P. aeruginosa biofilm with low OD value (0.18) showed signs of considerable hemocompatibility and antibacterial activity. Besides, according to an in vivo assay study, the wounds of mice treated with the cross-linked lignin–agarose/SF/ZnCr2O4 nanobiocomposite scaffold were almost completely healed in five days. Aside from these biological tests, the structural features were evaluated by FT-IR, EDX, FE-SEM, and TG analyses, as well as swelling ratio, rheological, and compressive mechanical study tests. Additionally, it was concluded that adding silk fibroin and ZnCr2O4 nanoparticles could enhance the mechanical tensile properties of cross-linked lignin–agarose hydrogel, and also an elastic network was characterized for this designed nanobiocomposite.

Given the important aspects of wound healing approaches, in this work, an innovative biocompatible nanobiocomposite scaffold was designed and prepared based on cross-linked lignin–agarose hydrogel, extracted silk fibroin solution, and zinc chromite (ZnCr2O4) nanoparticles.  相似文献   
10.
PURPOSE: The incidence of anal cancer is high in patients with anal condyloma. HIV increases this risk. We analyzed anal mucosa from normal individuals and individuals with condyloma. EXPERIMENTAL DESIGN: Normal anal mucosa from 155 consecutively recruited patients (102 HIV-positive and 53 HIV-negative) with anal condyloma was compared with that obtained from 30 HIV-negative patients after hemorrhoid surgery (controls). Langerhans' cells (LCs), T lymphocytes, and viruses [EBV, cytomegalovirus, herpes simplex virus 1, and human papillomavirus (HPV) types] in anal mucosa and HIV load and CD4 T-lymphocyte counts in the serum were characterized. RESULTS: None of the control individuals had anal squamous intraepithelial lesion or HPV versus 19 HIV-positive and 4 HIV-negative patients with anal condyloma (P = 0.07). The number of LCs/mm in anal tissue was significantly higher in HIV-negative patients with condylomata (median, 30; range, 2-130) than in HIV-positive patients (median, 15; range, 0-100) or in controls (median, 17; range, 4-35). In HIV-negative individuals, the occurrence of condylomata was linked with a higher number of LCs. Significant differences were observed between HIV-positive and HIV-negative patients with anal condylomata:number of LCs/mm anal tissue, oncogenic HPV (26% versus 8%), other current infections (35.6% versus 5%), being male (93% versus 74%). Multivariate regression analysis found HIV as the only risk factor for a decrease in the number of LCs (odds ratio, 6; 95% confidence interval, 2.28-16.1; P < 0.001) and the serum HIV load (odds ratio, 4.9; 95% confidence interval, 1.1-21.4 log/ml; P < 0.03) but not the serum CD4 T-lymphocyte rate as a predictive risk factor for having <17 LCs/mm tissue. CONCLUSION: HPV increases the number of LCs in anal mucosa in HIV-negative individuals. HIV alters anal dendritic cells, likely leading to an increase in anal cancer risk.  相似文献   
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