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71.
Standardized criteria for diagnosis and response assessment are needed to interpret and compare clinical trials and for approval of new therapeutic agents by regulatory agencies. Therefore, a National Cancer Institute–sponsored Working Group (NCI-WG) on chronic lymphocytic leukemia (CLL) published guidelines for the design and conduct of clinical trials for patients with CLL in 1988, which were updated in 1996. During the past decade, considerable progress has been achieved in defining new prognostic markers, diagnostic parameters, and treatment options. This prompted the International Workshop on Chronic Lymphocytic Leukemia (IWCLL) to provide updated recommendations for the management of CLL in clinical trials and general practice.  相似文献   
72.
Resistance to apoptosis is an important component of the overall mechanism which drives the tumorigenic process. EBV is a ubiquitous human gamma-herpesvirus which preferentially establishes latent infection in viral infected B-lymphocytes. EBNA1 is typically expressed in most forms of EBV-positive malignancies and is important for replication of the latent episome in concert with replication of the host cells. Here, we investigate the effects of EBNA1 on survivin up-regulation in EBV-infected human B-lymphoma cells. We present evidence which demonstrates that EBNA1 forms a complex with Sp1 or Sp1-like proteins bound to their cis-element at the survivin promoter. This enhances the activity of the complex and up-regulates survivin. Knockdown of survivin and EBNA1 showed enhanced apoptosis in infected cells and thus supports a role for EBNA1 in suppressing apoptosis in EBV-infected cells. Here, we suggest that EBV encoded EBNA1 can contribute to the oncogenic process by up-regulating the apoptosis suppressor protein, survivin in EBV-associated B-lymphoma cells.  相似文献   
73.
The histological distribution of the lung-associated immune system (LAIS) and the expressional pattern of melatonin receptors are still unknown in birds. The aim of the present study was to determine the localization of the bronchus-associated lymphoid tissue (BALT nodule) in a tropical bird, the Indian jungle bush quail, Perdicula asiatica. We also demonstrate the expression of melatonin receptor types (Mel1a and Mel1b) in order to propose an immunomodulatory role of melatonin in LAIS. Localization of melatonin receptors in the lung of the Indian jungle bush quail, P. asiatica was supported immunohistochemically and by Western blot analysis using specific antibodies for those receptors. Immunolocalization for Mel1b receptor was noted in the bronchial region of the lungs, in finger-like projections of mucosal foldings, in lymphocytes in the BALT nodule as well as in free form. In contrast, immunolocalization for Mel1a receptor was noted in various areas of the lung instead of in the bronchial region. Western blot analysis showed a single band at 37 and 39 kDa for Mel1a and Mel1b receptors, respectively, with the latter showing higher expression. The results demonstrate a well-developed LAIS and region-specific distribution of melatonin receptors in the lung and provide evidence for a possible functional role for melatonin in the LAIS of birds.  相似文献   
74.
We report a case of eosinophilic enteritis involving the proximal small bowel, a relatively rare entity, presenting unusually as enteroliths in a 68-year-old man with complaints of anemia, malena and abdominal pain. The disease if diagnosed in the initial stages responds well to medical treatment but if associated with complications or misdiagnosed, surgical modality is the treatment of choice. In our case, the patient presented with enteroliths and strictures. Resection and anastomosis of the small bowel containing stones was carried out. Histopathology confirmed the diagnosis as eosinophilic enteritis.  相似文献   
75.
Cardiac hypertrophy is a common response to injury and hemodynamic stress and an important harbinger of heart failure and death. Herein, we identify the Kruppel-like factor 15 (KLF15) as an inhibitor of cardiac hypertrophy. Myocardial expression of KLF15 is reduced in rodent models of hypertrophy and in biopsy samples from patients with pressure-overload induced by chronic valvular aortic stenosis. Overexpression of KLF15 in neonatal rat ventricular cardiomyocytes inhibits cell size, protein synthesis and hypertrophic gene expression. KLF15-null mice are viable but, in response to pressure overload, develop an eccentric form of cardiac hypertrophy characterized by increased heart weight, exaggerated expression of hypertrophic genes, left ventricular cavity dilatation with increased myocyte size, and reduced left ventricular systolic function. Mechanistically, a combination of promoter analyses and gel-shift studies suggest that KLF15 can inhibit GATA4 and myocyte enhancer factor 2 function. These studies identify KLF15 as part of a heretofore unrecognized pathway regulating the cardiac response to hemodynamic stress.  相似文献   
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77.
Background: Variable airflow obstruction and airway hyperresponsiveness (AHR) are features of asthma, which are absent in nonasthmatic eosinophilic bronchitis (EB). Airway remodelling is characteristic of both conditions suggesting that remodelling and airway dysfunction are disassociated, but whether the airway geometry differs between asthma and nonasthmatic EB is uncertain. Methods: We assessed airway geometry by computed tomography (CT) imaging in asthma vs EB. A total of 12 subjects with mild–moderate asthma, 14 subjects with refractory asthma, 10 subjects with EB and 11 healthy volunteers were recruited. Subjects had a narrow collimation (0.75 mm) CT scan from the aortic arch to the carina to capture the right upper lobe apical segmental bronchus (RB1). In subjects with asthma and EB, CT scans were performed before and after a 2‐week course of oral prednisolone (0.5 mg/kg). Results: Mild–moderate and refractory asthma were associated with RB1 wall thickening in contrast to subjects with nonasthmatic EB who had maintained RB1 patency without wall thickening [mean (SD) % wall area and luminal area mild‐t0‐moderate asthma 67.7 (7.3)% and 6.6 (2.8) mm2/m2, refractory asthma 67.3 (5.6)% and 6.7 (3.4) mm2/m2, healthy control group 59.7 (6.3)% and 8.7 (3.8) mm2/m2, EB 61.4 (7.8)% and 11.1 (4.6) mm2/m2 respectively; P < 0.05]. Airway wall thickening of non‐RB1 airways generation three to six was a feature of asthma only. There was no change in airway geometry of RB1 after prednisolone. Proximal airway wall thickening was associated with AHR in asthma (r = ?0.56; P = 0.02). Conclusions: Maintained airway patency in EB may protect against the development of AHR, whereas airway wall thickening may promote AHR in asthma.  相似文献   
78.
Trichosanthes dioica Roxb. (Cucurbitaceae), called pointed gourd in English, is a dioecious climber grown widely in the Indian subcontinent. The present study assessed the influence of treatment of hydroalcoholic extract of Trichosanthes dioica root (TDA) on Ehrlich ascites carcinoma (EAC) in Swiss albino mice with effects on antioxidant systems. Twenty-four hours after intraperitoneal inoculation of tumor (EAC) cells in mice, TDA was administered at 25 and 50 mg/kg for 8 consecutive days. On the 9(th) day, half of the mice were sacrificed for estimation of tumor proliferation, hematological, and hepatic antioxidative parameters. The rest were kept for assessment of survival parameters. TDA exhibited dose dependent and significant increase in tumor weight, tumor volume, packed cell volume and viable cells and reduced non-viable cells and life span of EAC bearing animals. Hematological parameters were significantly worsened in TDA-treated mice. TDA treatment significantly aggravated the hepatic antioxidative parameters. The present study demonstrated that T. dioica root possessed tumor promoting activity in EAC bearing albino mice, plausibly mediated by attenuation of endogenous antioxidant systems.  相似文献   
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80.
Malaria is a major global threat, that results in more than 2 million deaths each year. The treatment of malaria is becoming extremely difficult due to the emergence of drug-resistant parasites, the absence of an effective vaccine, and the spread of insecticide-resistant vectors. Thus, malarial therapy needs new chemotherapeutic approaches leading to the search for new drug targets. Here, we discuss different approaches to identifying novel antimalarial drug targets. We have also given due attention to the existing validated targets with a view to develop novel, rationally designed lead molecules. Some of the important parasite proteins are claimed to be the targets; however, further in vitro or in vivo structure-function studies of such proteins are crucial to validate these proteins as suitable targets. The interactome analysis among apicoplast, mitochondrion and genomic DNA will also be useful in identifying vital pathways or proteins regulating critical pathways for parasite growth and survival, and could be attractive targets. Molecules responsible for parasite invasion to host erythrocytes and ion channels of infected erythrocytes, essential for intra-erythrocyte survival and stage progression of parasites are also becoming attractive targets. This review will discuss and highlight the current understanding regarding the potential antimalarial drug targets, which could be utilized to develop novel antimalarials.  相似文献   
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