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Regan N Theiler Angela M Caliendo Sabine Pargman B Denise Raynor Sarah Berga Melissa McPheeters Denise J Jamieson 《Journal of clinical virology》2006,37(4):313-316
BACKGROUND: Cytomegalovirus (CMV) infection, which is the most common congenitally transmitted infection, affects approximately 1% of neonates worldwide. Despite its prevalence, no convenient screening test for neonatal CMV infection has been implemented. OBJECTIVE: The purpose of this pilot study was to evaluate the feasibility and yield of screening umbilical cord blood for CMV DNA emiaby quantitative PCR. STUDY DESIGN: Umbilical cord blood was tested for CMV DNAemia using a commercial quantitative PCR assay. Maternal CMV serostatus at the time of delivery was assessed by testing for CMV IgG and IgM antibodies in serum. CONCLUSIONS: Screening for congenital CMV infection with PCR is easily incorporated into routine labor and delivery care using discarded cord blood specimens to identify neonates whose infection is otherwise undiagnosed. Among 433 infants tested, two (0.5%) had DNAemia detected in cord blood, one of whom was symptomatic, and both of whose mothers were CMV IgG positive and IgM negative. Viremic neonates identified by screening with PCR may be at high risk of developing long-term neurological complications of CMV infection and cannot reliably be identified using clinical presentation or maternal serology. Because of its convenience, cord blood CMV screening with PCR should be further investigated for incorporation into neonatal screening protocols. 相似文献
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William B. Hansen Anne E. Raynor Bonnie H. Wolkenstein 《Journal of behavioral medicine》1991,14(3):205-224
Heavy drinkers, moderate drinkers, light drinkers, and nondrinkers were asked to rate a variety of negative health and social consequences of using alcohol. Subjects made probability ratings for fictional others who were heavy, moderate, or light drinkers or nondrinkers. Subjects also made probability ratings for themselves as hypothetical heavy, moderate, or light drinkers or nondrinkers and for themselves actually. A pattern of perceived personal immunity was found across groups. Subjects rated fictional others and themselves as hypothetical drinkers to be more likely to experience negative consequences than their actual selves. All groups of subjects (heavy, moderate, and light drinkers and abstainers) rated their actual chances of experiencing negative consequences to be approximately equal. In contrast, heavy drinkers saw the effects of drinking for other heavy drinkers as less likely than did subjects who had light or abstinent drinking patterns who rated fictional heavy drinkers. These findings suggest that individuals who drink more tend to deny the potential harm that may result from alcohol consumption. Short-term social consequences were viewed as most likely to occur. Long-term consequences were perceived as least likely to occur.This research was supported in part by grant 1-R01-AA06201 from the National Institute on Alcohol Abuse and Alcoholism. 相似文献
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Objective: The purpose of this study was to determine if granulocyte colony-stimulating factor (G-CSF) is normally present in amniotic fluid and then to determine if amniotic-fluid G-CSF levels are affected by labor and intrauterine infection.Methods: Amniotic fluid was collected from 35 patients in 4 groups: no labor, early labor, late labor, and labor plus chorioamnionitis. G-CSF levels were measured by enzyme-linked immunosorbent assay (ELISA).Results: The mean amniotic-fluid G-CSF concentrations prior to labor were lower than during labor (0.49 +/- 0.25 ng/ml for prior to labor vs. 1.83 +/- 1.0 ng/ml for labor, P < 0.001). With chorioamnionitis, the mean levels were elevated compared with normal labor (25.0 +/- 4.8 ng/ml for chorioamnionitis vs. 1.83 +/- 1.0 ng/ml for normal labor, P < 0.0001). In early and late labor, G-CSF was higher than prior to labor (0.49 +/- 0.25 ng/ml for no labor vs. 1.48 +/- 1.0 ng/ml for early labor, P < 0.02, vs. 2.2 +/- 0.8 ng/ml for late labor, P < 0.0005). The mean concentrations in early and late labor were not different.Conclusions: G-CSF is present in amniotic fluid and increased with labor. When labor is complicated by chorioamnionitis, G-CSF is significantly elevated. 相似文献
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Acute hematogenous peripelvic infections are common in tropical climates. However, in more temperate regions, this is a rare and often overlooked diagnosis. Because of the subtle and subacute nature of the symptoms, the diagnosis is often delayed. We report our experience with nine children treated for a hematogenous peripelvic infection. The hospital and clinic charts were reviewed of nine consecutive patients with the diagnosis of a peripelvic abscess. Patients ranged in age from 2 to 13 years. Symptoms were present from 5 to 20 days. The most consistent symptom was a hip-flexion pseudocontracture (eight patients). The initial diagnosis was correct in only three patients. Computed tomography (CT) scan was diagnostic in all nine patients, providing diagnosis and localization. Seven of the nine patients underwent irrigation and debridement followed by a variable course of intravenous (i.v.) and oral antibiotics. All seven had rapid resolution of their symptoms. Two patients were treated with i.v. antibiotics alone, one of whom had a recurrence of symptoms. All nine patients had microbiologic confirmation of the infecting organisms [seven at surgery, one from blood cultures, one from sacroiliac (SI) joint aspiration]. Eight of the nine were infected by Staphylococcus aureus and one by group A Streptococcus. All had complete resolution of their symptoms at follow-up. Although acute retrofascial abscesses are rare in temperate climates, they should be considered in the differential diagnosis in the child with lower abdominal or hip pain. CT scan was the most helpful diagnostic test in these patients. Surgical drainage resulted in the most consistent results in this small series of patients. 相似文献
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Sensorineural hearing loss has been identified in several types of muscular dystrophy, but few studies have investigated any relationship between Duchenne muscular dystrophy and hearing. An animal model of Duchenne muscular dystrophy, themdx mouse, exhibits the same genetic defect as humans. We performed brainstem auditory evoked responses on mdx and control mice in order to assess sensorineural hearing loss. The amplitude and latency of wave I for each animal were measured at increasing sound pressure levels. A significant increase in threshold and a decrease in wave I amplitude were found in the mdx mice. These results indicate that significant sensorineural hearing loss is associated with muscular dystrophy in the mdx mouse. Possible cellular mechanisms contributing to the hearing deficit are presented. 相似文献
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Anorexia nervosa (AN) is a serious life-threatening illness that typically has its onset during the adolescent years. Evidence regarding the optimal treatment of AN in children and teenagers is growing; however, much remains unknown. Although current treatment approaches vary in Canada and elsewhere, the evidence to date indicates that family-based treatment (FBT) is the most effective treatment for children and teenagers with AN. A key component of the FBT model is that the parents are given the responsibility to return their child to physical health and ensure full weight restoration. An understanding of the basic principles and philosophy underlying FBT allows the physician to initiate elements of this evidence-based intervention to young patients with AN and their families. 相似文献
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Role of extracellular adenosine triphosphate in the cytotoxic T- lymphocyte-mediated lysis of antigen presenting cells 总被引:4,自引:0,他引:4
The lysis of antigen presenting cells (APCs) by cytotoxic T lymphocytes (CTLs) may be one mechanism whereby an immune response is downregulated by Staphylococcus superantigens. Disappearance of monocytes/macrophages from staphylococcal enterotoxin A (SEA)-activated peripheral blood mononuclear cell (PBMC) cultures, but not from control PBMC cultures was seen by flow cytometry. Recently, adenosine triphosphate (ATP) has been described as an effector molecule in CTL-mediated lysis of some murine tumor target cells. We have also shown that ATP caused the lysis of human macrophages, and that treatment of cells with interferon gamma (IFN gamma) rendered macrophages significantly more sensitive to ATP than untreated cells. To show that this purine nucleotide may play a role in modulating the immune system, we generated human CTLs that were stimulated with SEA, and used them as effector cells against SEA-pulsed autologous macrophages. CTLs were found to specifically lyse SEA-pulsed macrophages, while control, unpulsed, macrophages were unaffected. The addition of hexokinase, an enzyme that hydrolyzes ATP, significantly abrogated the killing of SEA-pulsed cells during the assay. In examining the mechanism of cytotoxicity, electron microscopy showed that macrophages incubated with both ATP and CTLs underwent necrosis, rather than apoptosis. From these results, it is suggested that ATP is released from CTLs during antigen presentation, and that IFN gamma- activated macrophages, which are inherently more sensitive to this mediator, are readily lysed and therefore removed from circulation, thus downregulating an immune response. 相似文献