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Microsporidia are highly specialized obligate intracellular organisms that are closely related to fungi. Although traditionally associated with diarrheal illness in patients with AIDS, extraintestinal infections involving various organs have been reported with increasing frequency in the past decade, particularly in immunocompromised hosts. Diagnosis is usually accomplished by light microscopic identification of spores in body fluids and tissues, using a variety of stains. Transmission electron microscopy, immunofluorescence assays, or molecular methods are necessary for identification to the genus and species level. Early diagnosis is essential for preventing the significant associated morbidity and mortality of extraintestinal microsporidiosis.  相似文献   
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Background

The Heartmate 3 (HM3) is a Conformiteé Européenne mark–approved left ventricular (LV) assist device (LVAD) with fully magnetically levitated rotor and features consisting of a wide range operational speeds, wide flow paths, and artificial pulse. We performed a hemodynamic-echocardiographic speed optimization evaluation in HM3-implanted patients to achieve optimal LV- and right ventricular (RV) shape.

Methods and Results

Sixteen HM3 patients underwent pump speed ramp tests with right heart catheterization. Three-dimensional echocardiographic (3DE) LV and RV datasets (Philips) were acquired, and volumetric (Tomtec) and shape (custom software) analyses were performed (LV: sphericity, conicity; RV: septal and free-wall curvatures). Data were recorded at up to 13 speed settings. Speed changes were in 100-rpm steps, starting at 4600 rpm and ramping up to 6200 rpm. 3DE was feasible in 50% of the patients. Mean original speed was 5306 ± 148 rpm. LV end-diastolic (ED) diameter (?0.15 ± 0.09 cm/100 rpm) and volumes (ED: 269 ± 109 mL to 175 ± 90 mL; end-systolic [ES]: 234 ± 111 mL to 146 ± 81 mL) progressively decreased as the shape became less spherical and more conical; RV volumes initially remained stable, but at higher speeds increased (ED: from 148 ± 64 mL to 181 ± 92 mL; ES: 113 ± 63 mL to 130 ± 69 mL). On average, the RV septum became less convex (bulging toward the LV) at the highest speeds.

Conclusions

LV and RV shape changes were noted in HM3-supported patients. Although a LV volumetric decrease and shape improvement was consistently noted, RV volumes grew in response to increase in speed above a certain point. A next concern would be whether understanding of morphologic and function changes in LV and RV during LVAD speed change assessed with the use of 3DE helps to optimize LVAD speed settings and improve clinical outcomes.  相似文献   
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OBJECTIVE: Sarcolipin (SLN) is a novel 31-amino-acid protein associated with the sarcoplasmic reticulum (SR) whose function in cardiac muscle is poorly defined. In this study, we tested the hypothesis that SLN is a regulator of SR Ca(2+) transport function by overexpressing SLN in adult rat ventricular myocytes which express low levels of SLN. METHODS: Expression of SLN mRNA in rat tissues was analyzed by Northern blot as well by RT-PCR analysis. To define the role of SLN in cardiac muscle contractility, we overexpressed SLN in adult rat ventricular myocytes using adenoviral gene transfer techniques. Localization of SLN in the adult rat ventricular myocytes was determined using confocal microscopy. Myocyte contractility and calcium transients were measured using edge detection and Fura 2AM. RESULTS: Our results demonstrate that overexpression of SLN decreased the cell shortening significantly when compared to control myocytes, whereas the time to peak contraction was not altered. In addition, SLN overexpression prolonged the time of 50% relaxation. Calcium transient analysis shows that time to 50% decay of [Ca(2+) ]i was markedly prolonged in SLN-overexpressing myocytes (control -245.0+/-3.78 vs. SLN -199.0+/-3.25 ms, p<0.001). However, there were no significant differences in peak amplitudes of [Ca(2+)](i) between SLN-overexpressing and control myocytes. We further demonstrate that SLN is localized within the SR membrane similar to PLB and SR Ca(2+) ATPase. Co-immunoprecipitation studies indicate that SLN can physically interact with phospholamban. CONCLUSIONS: We conclude that SLN may play an important role in regulating the SR calcium ATPase pump, possibly by interacting with phospholamban.  相似文献   
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AimVasculotide (VT), an angiopoietin‐1 mimetic peptide, exerts neuroprotective effects in type one diabetic (T1DM) rats subjected to ischemic stroke. In this study, we investigated whether delayed VT treatment improves long‐term neurological outcome after stroke in T1DM rats.MethodsMale Wistar rats were induced with T1DM, subjected to middle cerebral artery occlusion (MCAo) model of stroke, and treated with PBS (control), 2 µg/kg VT, 3 µg/kg VT, or 5.5 µg/kg VT. VT treatment was initiated at 24 h after stroke and administered daily (i.p) for 14 days. We evaluated neurological function, lesion volume, vascular and white matter remodeling, and inflammation in the ischemic brain. In vitro, we evaluated the effects of VT on endothelial cell capillary tube formation and inflammatory responses of primary cortical neurons (PCN) and macrophages.ResultsTreatment of T1DM‐stroke with 3 µg/kg VT but not 2 µg/kg or 5.5 µg/kg significantly improves neurological function and decreases infarct volume and cell death compared to control T1DM‐stroke rats. Thus, 3 µg/kg VT dose was employed in all subsequent in vivo analysis. VT treatment significantly increases axon and myelin density, decreases demyelination, decreases white matter injury, increases number of oligodendrocytes, and increases vascular density in the ischemic border zone of T1DM stroke rats. VT treatment significantly decreases MMP9 expression and decreases the number of M1 macrophages in the ischemic brain of T1DM‐stroke rats. In vitro, VT treatment significantly decreases endothelial cell death and decreases MCP‐1, endothelin‐1, and VEGF expression under high glucose (HG) and ischemic conditions and significantly increases capillary tube formation under HG conditions when compared to non‐treated control group. VT treatment significantly decreases inflammatory factor expression such as MMP9 and MCP‐1 in macrophages subjected to LPS activation and significantly decreases IL‐1β and MMP9 expression in PCN subjected to ischemia under HG conditions.ConclusionDelayed VT treatment (24 h after stroke) significantly improves neurological function, promotes vascular and white matter remodeling, and decreases inflammation in the ischemic brain after stroke in T1DM rats.  相似文献   
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Burkitt's lymphoma(BL) is an aggressive form of nonHodgkin's B-cell lymphoma with three variants namely endemic, sporadic, and immunodeficiency-associated types. It is endemic in Africa and sporadic in other parts of the world. While the endemic form is widely reported to occur in early childhood and commonly involves the jaw bones, the sporadic form typically presents as an abdominal mass. This presentation reports a rare case of sporadic form of BL clinically manifesting as a generalized gingival enlargement in an immunocompetent adult male which demonstrated an aggressive behavior. The patient reported with a prominent anterior gingival swelling of 6 mo duration which slowly enlarged in size and associated with multiple lymph node involvement. Microscopic examination of the lesion using H, E and immunohistochemical diagnosis confirmed the diagnosis as BL. The patient succumbed to the disease before any therapy could be instituted. Since a wide array of causes can be attributed to gingival enlargements, it is necessary to consider malignancies as one of the important differential diagnosis so as to facilitate the need for appropriate diagnosis and prompt treatment.  相似文献   
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Routine angiographic follow-up after bare-metal stent implantation has been associated with an increase in coronary revascularization. The impact of angiographic follow-up after drug-eluting stent placement remains poorly characterized. The prospective, randomized, single-blinded SPIRIT III trial assigned patients to the everolimus-eluting stent or the paclitaxel-eluting stent (PES). Major adverse cardiovascular events (cardiac death, myocardial infarction, and ischemia-driven target lesion revascularization [ID-TLR]) at 3 years were assessed by angiographic versus clinical-only follow-up at 8 months ± 28 days and a landmark survival analysis from 9 months to 3 years. Of 1,002 patients, 564 patients were assigned to angiographic follow-up at 8 months ± 28 days and 438 patients underwent clinical follow-up alone. Three-year major adverse cardiovascular event rates were 10.6% in the angiographic group and 12.0% in the clinical follow-up group (p = 0.64). Ischemia-driven revascularization increased twofold at 9 months, but no difference was noted in ID-TLR for either device. Non-ID-TLR was significantly higher in patients in the angiographic group (4.5% vs 1.0%, p = 0.002), a difference resulting from PES (9.1% vs 0.7%, p = 0.0007) rather than everolimus-eluting stent (2.2% vs 1.1%, p = 0.36) treatment. The landmark analysis showed no significant differences between the angiographic and clinical follow-up groups from 9 months to 3 years of major clinical outcomes. In conclusion, routine angiographic follow-up in SPIRIT III did not increase rates of ID-TLR compared to clinical follow-up alone. Despite higher nonischemia-driven revascularization rates with angiographic follow-up of patients with PESs, none of the safety end points were adversely affected.  相似文献   
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The prevalence of endobronchial tuberculosis (EBTB) in patients with active tuberculosis is about 10% to 40%. The most common complication of EBTB is bronchial stenosis. Fistula formation by pulmonary tuberculosis is a very rare complication and is most commonly bronchopleural. The authors present a 53-year-old woman presented with chronic cough and abnormality in chest computed tomography scan. According to chest computed tomography scan finding, bronchoscopic study was done and bronchial lavage was obtained. Bronchial lavage was positive for acid fast bacilli. Bronchoscopy showed fistula formation between the right and left main bronchus, a rare manifestation of EBTB. The patient was treated with antituberculosis therapy, and her symptoms improved and radiological findings showed regression of pulmonary lesions.  相似文献   
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Purpose: To determine the prevalence of oral mucosal lesions associated with tobacco among patients visiting the dental hospital. Materials and Methods: A selection of 1525 patients visiting the Department of Oral Medicine and Radiology were interviewed regarding tobacco habits. Examination of the oral cavity was performed by trained examiners under good illumination using diagnostic instruments. Oral mucosal lesions were diagnosed based on the clinical features. Results: The patients were divided into groups based on their tobacco habits. Out of 1525 patients, 359 patients (23.5%) had the habit and 265 (73.8%) of them had oral mucosal lesions. Leukoedema was the most prevalent lesion. Leukoplakia was found in 3.5% of the patients. Malignancy was found only among chewers. Conclusion: Nearly three-quarters of the patients with the tobacco habit had oral mucosal lesions. This emphasises that routine examination of oral mucosa is important and that the patients must be motivated to quit this harmful habit.  相似文献   
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