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The diagnosis of pleural tuberculosis continues to be a challenge due to the low sensitivity of traditional diagnostic methods. Better and more rapid tests are needed for diagnosis of pleural TB. In this study, pleural fluids were tested with rapid test to determine Mycobacterium tuberculosis (MTB antigen). Affinity chromatography was used to purify specific polyclonal antibodies against MTB antigen. Pleural samples after decontamination were treated with proteinase K. Rapid test for pleural fluids was prepared by specific antibody. Rapid test was performed on 85 pleural fluid patients. The patients had a mean age of 46.55 ± 15.96 years and 38 were men. The performance of rapid test, using proteinase K, was found to be the most impressive: sensitivity 93%, specificity 94%, PPV 90%, and NPV 96% compared with adenosine deaminase test (ADA), PCR, smear, and culture. The present study did demonstrate that modified TB rapid test can substantially improve the diagnosis of extrapulmonary TB.  相似文献   
44.
High Mobility Group A1 (HMGA1) is an architectural chromatin factor that promotes neoplastic transformation and progression. However, the mechanism by which HMGA1 exerts its oncogenic function is not fully understood. Here, we show that cyclin E2 (CCNE2) acts downstream of HMGA1 to regulate the motility and invasiveness of basal-like breast cancer cells by promoting the nuclear localization and activity of YAP, the downstream mediator of the Hippo pathway. Mechanistically, the activity of MST1/2 and LATS1/2, the core kinases of the Hippo pathway, are required for the HMGA1- and CCNE2-mediated regulation of YAP localization. In breast cancer patients, high levels of HMGA1 and CCNE2 expression are associated with the YAP/TAZ signature, supporting this connection. Moreover, we provide evidence that CDK inhibitors induce the translocation of YAP from the nucleus to the cytoplasm, resulting in a decrease in its activity. These findings reveal an association between HMGA1 and the Hippo pathway that is relevant to stem cell biology, tissue homeostasis, and cancer.  相似文献   
45.
Carbon nanofilament and nanotubes (CNTs) have shown promise for enhancing the mechanical properties of fiber-reinforced composites (FRPs) and imparting multi-functionalities to them. While direct mixing of carbon nanofilaments with the polymer matrix in FRPs has several drawbacks, a high volume of uniform nanofilaments can be directly grown on fiber surfaces prior to composite fabrication. This study demonstrates the ability to create carbon nanofilaments on the surface of carbon fibers employing a synthesis method, graphitic structures by design (GSD), in which carbon structures are grown from fuel mixtures using nickel particles as the catalyst. The synthesis technique is proven feasible to grow nanofilament structures—from ethylene mixtures at 550 °C—on commercial polyacrylonitrile (PAN)-based carbon fibers. Raman spectroscopy and electron microscopy were employed to characterize the surface-grown carbon species. For comparison purposes, a catalytic chemical vapor deposition (CCVD) technique was also utilized to grow multiwall CNTs (MWCNTs) on carbon fiber yarns. The mechanical characterization showed that composites using the GSD-grown carbon nanofilaments outperform those using the CCVD-grown CNTs in terms of stiffness and tensile strength. The results suggest that further optimization of the GSD growth time, patterning and thermal shield coating of the carbon fibers is required to fully materialize the potential benefits of the GSD technique.  相似文献   
46.

Background

Current recommendations for evaluation and safe discharge of penetrating chest trauma patients regarding pneumothorax (PTX) include a Chest X Ray (CXR) at the Emergency Department (ED) upon arrival and second CXR after 3 h if the first one is negative.

Purpose

To compare CXRs taken at the first and third hours of ED arrival and evaluate a 1 h period of observation instead of 3 h for safe discharge of patients with penetrating chest trauma.

Methods

In this cross-sectional study, all asymptomatic patients with penetrating chest trauma referred to a level 1 trauma center with negative initial Postero-Anterior (PA) CXRs (hour 0) were enrolled. Those with intoxication, tube thoracostomy, chest computed tomography, evidence of abdominal penetration, an overall elapsed timed of more than 1 h for admission to the ED, and refusal to take part in the study were excluded. Patients underwent subsequent PA CXRs at hours 1 and 3. A phone call follow up after 24 h was organized for each patient.

Results

A total of 68 patients were enrolled. There was 100 % concordance among CXRs performed at hours 1 and 3 in the study population. None of the patients showed clinical deterioration or PTX in CXR at hour 1 if remained asymptomatic during the first hour of observation.

Conclusion

Asymptomatic patients with penetrating chest trauma, negative initial PA CXR, no signs of intoxication, and no deterioration during the first hour of observation may be considered for discharge. Further evidence is required to make recommendations based on these findings.
  相似文献   
47.

Introduction

The assessment of the ventricular myocardial substrate critically depends on the size of mapping electrodes, their orientation with respect to wavefront propagation, and interelectrode distance. We conducted a dual-center study to evaluate the impact of microelectrode mapping in patients undergoing catheter ablation (CA) of ventricular tachycardia (VT).

Methods

We included 21 consecutive patients (median age, 68 [12], 95% male) with structural heart disease undergoing CA for electrical storm (n = 14) or recurrent VT (n = 7) using the QDOT Micro catheter and a multipolar catheter (PentaRay, n = 9). The associations of peak-to-peak maximum standard bipolar (BVc) and minibipolar (PentaRay, BVp) with microbipolar (BVμMax) voltages were respectively tested in sinus rhythm with mixed effect models. Furthermore, we compared the features of standard bipolar (BE) and microbipolar (μBE) electrograms in sinus rhythm at sites of termination with radiofrequency energy.

Results

BVμMax was moderately associated with both BVc (β = .85, p < .01) and BVp (β = .56, p < .01). BVμMax was 0.98 (95% CI: 0.93−1.04, p < .01) mV larger than corresponding BVc, and 0.27 (95% CI: 0.16−0.37, p < .01) mV larger than matching BVp in sinus rhythm, with higher percentage differences in low voltage regions, leading to smaller endocardial dense scar (2.3 [2.7] vs. 12.1 [17] cm2, p < .01) and border zone (3.2 [7.4] vs. 4.8 [20.1] cm2, p = .03) regions in microbipolar maps compared to standard bipolar maps. Late potentials areas were nonsignificantly greater in microelectrode maps, compared to standard electrode maps. At sites of VT termination (n = 14), μBE were of higher amplitude (0.9 [0.8] vs. 0.4 [0.2] mV, p < .01), longer duration (117 [66] vs. 74 [38] ms, p < .01), and with greater number of peaks (4 [2] vs. 2 [1], p < .01) in sinus rhythm compared to BE.

Conclusion

microelectrode mapping is more sensitive than standard bipolar mapping in the identification of viable myocytes in SR, and may facilitate recognition of targets for CA.  相似文献   
48.
Introduction: During recent years, the need for platelet concentrate (PC) has increased. Infusible platelet membranes (IPM) have been developed as an alternative to standard PCs, with the additional advantage of long shelf‐life and increased viral safety. In this study, IPM construction and the morphological and biological features of these microvesicles were surveyed to determine their binding capacities in vitro. Methods: Thirty‐five PC units prepared by the Iranian Blood Transfusion Organization were used to produce IPM. Platelets were lysed by repeated cycles of freezing and thawing, virally inactivated with wet heat in the presence of different concentrations of sodium octanoate as a heat stabilizer, and then sonicated. IPM were separated, kept at 4 °C or lyophilized, and examined for binding to collagen and von Willebrand factor (VWF). Results: IPM retained the binding capacity for collagen and VWF, and the extent of VWF binding was dependent on the concentration of the heat stabilizer. Additionally, a higher binding capacity was demonstrated for liquid‐stored compared with lyophilized IPM. Conclusion: This study revealed the potential of IPM microvesicles to mimic the binding features of platelets in vitro.  相似文献   
49.
Snapping hip syndromes have been treated with open surgery for many years. Recently, endoscopic techniques have been developed for treatment of snapping hip syndromes with results that are at least comparable if not better than those reported for open procedures. The greater trochanteric pain syndrome is well known by orthopedic surgeons. However, deep understanding of the pathologic conditions generating pain in the greater trochanteric region and endoscopic access to it has only recently been described. Although evidence regarding endoscopic techniques for the treatment of the greater trochanteric pain syndrome is mainly anecdotal, early published reports are encouraging.  相似文献   
50.
Partial albinism with variable immunodeficiency are the two major characteristics of Griscelli syndrome type 2 (GS‐2). This syndrome is usually associated with a high mortality rate and commonly results in early childhood death. Patients suffer from different infections and experience crisis of HLH. HSCT remains the sole curative treatment for GS‐2. We prospectively analyzed the outcomes of transplantation with RIC regimen in five patients. The median age at transplantation was 21.6 months (range: 12–30). All of the patients underwent HSCT from HLA‐matched related donors. Currently, four patients are cured, and symptoms of recurrent infections and HLH crisis are not seen in them. The only patient who died had undergone HSCT in the accelerated phase of HLH. One patient who developed acute GvHD had a favorable response to therapy. No chronic GvHD occurred in patients. It seems that the use of RIC regimen as a method of transplant preparation is effective and tolerable in this group of patients with various comorbidities. It is recommended to carry out HSCT in these patients at lower ages, before presentations of different infections and HLH crisis.  相似文献   
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