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41.
Bartonella endocarditis is a disease of emerging importance that causes serious complications and high rates of mortality. Due to the fastidious nature of Bartonella species and their high degrees of antibiotic susceptibility, cultures of clinical samples most often remain sterile and valvular biopsy specimens, the best specimens for PCR amplification, are seldom available. Therefore, serology appears to be the easiest diagnostic tool. In order to determine the best cutoff value for serology and its predictive values for the detection of Bartonella endocarditis, we studied 48 patients with culture- and/or PCR-confirmed Bartonella endocarditis. We also applied these serological criteria to 156 patients with blood culture-negative endocarditis. Furthermore, we compared the kinetics of the antibody responses to Bartonella spp. in order to estimate the value of serology for prediction of the occurrence of relapses. A titer of > or = 1:800 for immunoglobulin G antibodies to either Bartonella henselae or B. quintana has a positive predictive value of 0.810 for the detection of chronic Bartonella infections in the general population and a value of 0.955 for the detection of Bartonella infections among patients with endocarditis. When this cutoff was applied to 156 patients with blood culture-negative endocarditis, we were able to diagnose Bartonella infections in an additional 45 patients with definite endocarditis for whom a positive Bartonella serology was the only evidence of infection. On follow-up, the kinetics of the decrease in antibody titers were significantly delayed in two patients with relapses. In conclusion, we recommend the determination of antibodies to both B. quintana and B. henselae and the use of a cutoff value of 1:800 for the diagnosis of Bartonella endocarditis. We propose that this criterion, which may also help with the detection of late relapses, be included as a major criterion in the Duke criteria for the diagnosis of infective endocarditis.  相似文献   
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F Rey  G Donker  I Hirsch  J C Chermann 《Virology》1991,181(1):165-171
Differential susceptibility of four diverse HIV strains to inhibition of infection of CD4+ CEM cells by anti-CD4 monoclonal antibodies was studied. The highly cytopathic HIV-1 246 and NDK strains were able to infect CEM cells and undergo several cycles of replication at saturating doses of LEU3-A, OKT4-A, and 13B8-2 monoclonal antibodies, whereas propagation of reference HIV-1 BRU and weakly cytopathic strain HIV-1 PAS was inhibited. Postadsorption treatment by anti-CD4 antibodies had stronger inhibitory effect than did treatment during the virus adsorption period. In parallel experiments, the same monoclonal antibodies successfully blocked syncytium formation between uninfected MT4 cells and CEM cells infected by all four HIV-1 virus strains tested. To explain these seemingly contradictory data we have postulated that anti-CD4 antibodies efficiently inhibit cell-to-cell but not virus-to-cell infection.  相似文献   
45.

Background

The Australian Carbohydrate Intolerance Study in Pregnant Women (ACHOIS) showed that treatment of pregnant women with mild gestational diabetes mellitus is beneficial for both women and their infants. It is still uncertain whether there are benefits of similar treatment for women with borderline gestational diabetes. This trial aims to assess whether dietary and lifestyle advice and treatment given to pregnant women who screen for borderline gestational diabetes reduces neonatal complications and maternal morbidities.

Methods/design

Design: Multicentre, randomised controlled trial. Inclusion criteria: Women between 240 and 346 weeks gestation with a singleton pregnancy, a positive oral glucose challenge test (venous plasma glucose ??7.8 mmol/L) and a normal oral 75 gram glucose tolerance test (fasting venous plasma glucose <5.5 mmol/L and a 2 hour glucose <7.8 mmol/L) with written, informed consent. Trial entry and randomisation: Women with an abnormal oral glucose tolerance test (fasting venous plasma glucose ??5.5 mmol/L or 2 hour glucose ??7.8 mmol/L) will not be eligible and will be offered treatment for gestational diabetes, consistent with recommendations based on results of the ACHOIS trial. Eligible women will be randomised into either the ??Routine Care Group?? or the ??Intervention Group??. Study groups: Women in the ??Routine Care Group?? will receive routine obstetric care reflecting current clinical practice in Australian hospitals. Women in the ??Intervention Group?? will receive obstetric care, which will include dietary and lifestyle advice, monitoring of blood glucose and further medical treatment for hyperglycaemia as appropriate. Primary study outcome: Incidence of large for gestational age infants. Sample size: A sample size of 682 women will be sufficient to show a 50% reduction in the risk of large for gestational age infants (alpha 0.05 two-tailed, 80% power, 4% loss to follow up) from 14% to 7% with dietary and lifestyle advice and treatment.

Discussion

A conclusive trial outcome will provide reliable evidence of relevance for the care of women with borderline glucose intolerance in pregnancy and their infants.

Trial registration

Australian New Zealand Clinical Trials Registry - ACTRN12607000174482  相似文献   
46.
BackgroundPatients with congenital long QT syndrome (LQTS) are at increased risk of ventricular arrhythmia, particularly during labour and the puerperium.CaseA 28-year-old primigravida with known LQTS underwent induction of labour at 41 weeks’ gestation using a Foley catheter balloon and IV oxytocin. Vaginal delivery with passive second stage and outlet forceps was undertaken with early epidural analgesia to prevent tachycardia and psychological stress. The patient gave birth to a healthy female, and had an uncomplicated postpartum period under continuous electrocardiogram monitoring.ConclusionVaginal delivery with use of oxytocin for the induction of labour can be safely undertaken in patients with LQTS.  相似文献   
47.
DNA copy gains are a common event in tumor growth. This study determines the gene dosage/amplification of seven tumor-related genes in patients undergoing vestibular schwannoma (VS) surgery and analyzes its clinical implications. Thirty-three patients undergoing surgery for VS were studied. Seven genes (EGFR, ERBB2, ERBB3, ERBB4, MDM2, MDM4, and NMYC) were analyzed by Quantitative real-time PCR. Copy gains were correlated with demographic, clinical and radiological data. Of the 33 samples, 48 % were positive for copy gains in at least one gene. There were no positive samples for gene amplification. A clinical correlation between tumor size and copy gains of ERBB2 was found. Patients with copy gains of this gene had larger tumors measured by diameter (p = 0.027) and volume (p = 0.005). Copy gains of EGFR, ERBB2, ERBB4, and MDM4 were associated with preoperative tinnitus. Contrary to other tumors of the central nervous system, development of VS does not appear to involve gene amplification. However, copy gains of certain tumor-related genes may play a role in the biological behavior of these neoplasms. Our findings support the role of ERBB2 in VS development and growth  相似文献   
48.

Background

Historically, the complete removable denture is the last prosthetic procedure to switch to digital techniques whose advantages are mainly observed in the laboratory stages; however, it is not possible to measure the depressibility of the oral mucosa using optical cameras, thus conventional impression techniques are still necessary. This article describes the clinical and laboratory procedure and practitioners appraisal of the first fifteen digitally designed complete removable dental prostheses.

Methods

Several systems are now available including the Wieland® Digital Denture® which offers a complete procedure. This system is composed of a five axis-milling machine combined with a laboratory scanner and a design software application. Fifteen rehabilitations were carried out using the Wieland® system.

Results

The practitioner’s role is simplified by intraoral recording with a central point and a reduced number of sessions. The prosthesis laboratory requires considerable investment in learning and equipment, making it possible to obtain ideal mounting assemblies in accordance with the occluso-prosthetic concept of bilateral balanced occlusion. The absence of polymerization and therefore of base deformation risks reduce the equilibration step. Finally, the creation of templates as an alternative to the assembly of teeth on wax makes it possible to functionally validate (masticatory and phonatory) the future dentures. However, this procedure still presented some limitations in terms of scanning and software scope of applications.

Conclusion

Digital denture design software is relatively efficient and helps to standardize clinical results. However, to this date, improvements of the software are still required for a routine use.
  相似文献   
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OBJECTIVE: To evaluate cyclin D1 expression in vestibular schwannoma and its relationship with histologic, clinical, and radiologic features. PATIENTS: Twenty-one patients with histologically confirmed vestibular schwannoma. INTERVENTION: Immunohistochemistry analysis was performed with anticyclin D1. Histopathologic features studied included Antoni pattern and nuclear and stromal degenerative changes. Clinical charts, audiometric data, and magnetic resonance imaging characteristics were reviewed. MAIN OUTCOME MEASURES: Cyclin D1 expression and its association with histologic, clinical, and radiologic findings. RESULTS: Cyclin D1 expression was found in 52% of cases. Cyclin D1 expression was more frequent in right-sided tumors (p = 0.02) and in tumors with nuclear degenerative changes (p < 0.0001). Patients with negative cyclin D1 expression had longer duration of deafness (p = 0.02) and higher 2,000-Hz hearing thresholds (p = 0.04) than cyclin D1+ patients. CONCLUSION: Cyclin D1 expression, present in nearly half of the cases, may play a role in the development of these tumors. Further studies are needed to fully understand the contributions of histopathologic and immunohistochemical factors to vestibular schwannoma biological activity.  相似文献   
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