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51.
52.
Lymphocytopenia has been reported in adults with pandemic influenza A/H1N1 2009 infection, but data in children are inconclusive. Data from 76 children presented with flu‐like symptoms between July and November 2009 and tested for pandemic influenza A/H1N1 2009 virus and white blood cell (WBC) counts were analyzed. Samples from 37 (48.7%) children resulted in a positive PCR assay for pandemic influenza A/H1N1 2009 virus. When comparing data from these children with data from 39 (51.3%) children with uncomplicated flu‐like illness and negative PCR assay for pandemic influenza A/H1N1 2009 virus, no difference in disease duration, median age, red blood cell count, hemoglobin concentration, C reactive protein concentration, and absolute neutrophil count was observed, whereas significant differences were apparent when considering WBC count, relative and absolute lymphocyte count, absolute lymphocyte count z‐score, and platelet count. Receiver operating characteristic curve analysis revealed that the best absolute lymphocyte count and absolute lymphocyte count z‐score cut‐points that simultaneously maximized sensitivity and specificity were 2,256 cells/µl and ?0.89, respectively, sensitivity being 0.81 (95% CI: 0.68–0.94), specificity 0.87 (95% CI: 0.77–0.98), positive predictive value 0.85 (95% CI: 0.74–0.97), and negative predictive value 0.83 (95% CI: 0.71–0.94). In conclusion, lymphocytopenia is a marker for influenza A/H1N1 2009 virus infection in children. Absolute lymphocyte count <2,556 cells/µl or absolute lymphocyte count z‐score < ?0.89 may be useful cut‐offs to discriminate against children at higher risk of infection during epidemics. Considering that the pandemic virus is highly likely to continue to circulate in the coming winter season, these findings provide direct and practical implications for the near future. J. Med. Virol. 83:1–4, 2011. © 2010 Wiley‐Liss, Inc.  相似文献   
53.
We investigated the molecular events of the ruthenium complex NAMI-A (0.1 mM for 1 h) on cell cycle G2-M arrest in KB carcinoma cells. Flow cytometry analysis showed a progressive accumulation of cells in S phase at 16 h, and in G2-M phase at 20 h after the end of treatment. NAMI-A pre-mitotic stop to cell proliferation was due to the maintenance of the phosphorylated, inactive, form of Cdk1, caused by the activation of the ATM/ATR checkpoint, as confirmed by the up-regulation and phosphorylation of Chk1. All these events are related to intracellular ruthenium accumulation, as confirmed by the lack of similar effects in cell lines unable to take the ruthenium compound up. Considering the dependence of NAMI-A cell cycle arrest on the dose and on the length of cell challenge, and considering the prolonged NAMI-A t1/2 in vivo in the lungs, we proved an even greater perturbation of the cell cycle regulating pathways in lung metastases of NAMI-A treated mice. The ex-vivo data confirm the interaction of the ruthenium compound NAMI-A with the ATM/ATR pathway, leading to the modulation of cell cycle regulating proteins, that can break the metastases cell cycle progression off.  相似文献   
54.
Reported herein is an unusual vascular tumor primary arising in the liver and exhibiting unique histopathological features. A 47‐year‐old woman underwent left hepatectomy because of a large hepatic mass. On histology the tumor had a composite pattern, consisting of angiomatous, retiform and solid areas, formed by oval to cuboidal to spindle cells, that expressed only endothelial markers (CD31 and factor VIII‐related antigen). These findings led to the diagnosis of a low‐grade vascular neoplasm with morphological features consistent with so‐called polymorphous hemangioendothelioma. The tumor was completely resected. At 24 month follow up the patient was alive, without evidence of disease. Polymorphous hemangioendothelioma is a rare vascular neoplasm, with borderline malignant potential, which usually occurs in lymph nodes and, rarely, at extranodal sites. Its classification as an entity has been questioned recently. The unusual morphological features of the present case, which do not fit neatly with any other recognized hemangioendothelioma subtype, indicate that the family of vascular tumors is broader than currently accepted. In addition the present case widens the spectrum of primary vascular tumors arising in the liver.  相似文献   
55.
Findings from observational studies have established that the arteriovenous fistula (AVF) is the preferred form of vascular access for chronic hemodialysis. Unfortunately, in a subset of patients with end-stage renal disease, an AVF cannot be placed or fails to mature. In these patients an alternate form of vascular access, either an arteriovenous graft (AVG) or central venous catheter (CVC) must be selected. In this review we discuss the findings and limitations of studies examining the effect of access type (AVG or CVC) on clinical endpoints including mortality, quality of life, occurrence of infections, as well as the impact of the different access types on resource requirements. Specifically, we examine whether findings from previous studies are valid and applicable to patients for whom an AVF is not possible, and outline the need for future randomized clinical trials addressing this question.  相似文献   
56.
We report the case of OTM who presented with dynamic aphasia following a stroke that occurred in the left basal ganglia. He showed drastically reduced spontaneous speech in the context of well preserved naming, repetition and comprehension skills. OTM was particularly impaired in generating words, sentences and phrases when cued by a stimulus allowing many response options. By contrast, when a single response was strongly suggested by a stimulus, he could generate verbal responses adequately. OTM's non-verbal response generation abilities varied across tasks. He performed in the normal range in a motor movement generation test and he produced as many figures as controls when tested on a figural fluency task. He showed, however, many perseverations on this test. Moreover in a random number generation task he produced more responses that were part of ascending and descending series of numbers. The patient's impairments are interpreted as a consequence of two deficits. The first of these consists of an inability to generate verbal responses particularly in situations of high competition and involves the function of left frontal regions. The second deficit is one of impaired novel thought generation as evidenced by perseverations. This second deficit has been proposed to be a function of basal ganglia damage.  相似文献   
57.
Stigmatizing, or discriminatory, perspectives and behaviour, which target individuals on the basis of their mental health, are observed in even the youngest school children. We conducted a systematic review of the published and unpublished, scientific literature concerning the benefits and harms of school-based interventions, which were directed at students 18 years of age or younger to prevent or eliminate such stigmatization. Forty relevant studies were identified, yet only a qualitative synthesis was deemed appropriate. Five limitations within the evidence base constituted barriers to drawing conclusive inferences about the effectiveness and harms of school-based interventions: poor reporting quality, a dearth of randomized controlled trial evidence, poor methods quality for all research designs, considerable clinical heterogeneity, and inconsistent or null results. Nevertheless, certain suggestive evidence derived both from within and beyond our evidence base has allowed us to recommend the development, implementation and evaluation of a curriculum, which fosters the development of empathy and, in turn, an orientation toward social inclusion and inclusiveness. These effects may be achieved largely by bringing especially but not exclusively the youngest children into direct, structured contact with an infant, and likely only the oldest children and youth into direct contact with individuals experiencing mental health difficulties. The possible value of using educational activities, materials and contents to enhance hypothesized benefits accruing to direct contact also requires investigation. Overall, the curriculum might serve as primary prevention for some students and as secondary prevention for others.  相似文献   
58.
Macrophage migration inhibitory factor (MIF), a cytokine originally reported in the 1960s as the prototypic T lymphokine, has emerged in recent years as a key factor regulating inflammatory responses. Both by directly activating immune cells, and by participating in activation entrained by other stimuli, MIF is important in innate and adaptive immune responses as well as tissue-specific mechanisms of damage. As a consequence of its involvement in multiple stages of the immune-inflammatory response, MIF has the potential to be involved in the pathogenesis of a range of immune-mediated inflammatory diseases affecting multiple organ systems. Diseases in which a role for MIF has been strongly validated include rheumatoid arthritis, inflammatory bowel disease, multiple sclerosis, atherosclerosis, asthma, inflammatory liver disease, and most recently systemic lupus erythematosus. Recent data have provided mechanisms of action for MIF which further support its suitability as a therapeutic target. Finally, MIF has a unique relationship with glucocorticoids, acting to counter-regulate their anti-inflammatory effects, such that MIF antagonist therapy may be a direct route to 'steroid-sparing'. Methods of targeting MIF therapeutically have also emerged in recent years, based on the unique protein structure of MIF which affords opportunities for direct antagonism by small molecules, as well as by protein therapeutics such as monoclonal antibodies. Clinical trials of MIF antagonist therapies are likely before the end of the current decade.  相似文献   
59.
Indolyl aryl sulfones bearing the 4,5-difluoro (10) or 5-chloro-4-fluoro (16) substitution pattern at the indole ring were potent inhibitors of HIV-1 WT and the NNRTI-resistant strains Y181C and K103N-Y181C. These compounds were highly effective against the 112 and the AB1 strains in lymphocytes and inhibited at nanomolar concentration the multiplication of the IIIBBa-L strain in macrophages. Compound 16 was exceptionally potent against RT WT and RTs carrying the K103N, Y181I, and L100I mutations.  相似文献   
60.
Radial shock waves therapy (RSWT) differs from extracorporeal shock waves therapy (ESWT) in that it produces a non-focused wave that is dissipated radially at the skin. Few studies have yet explored the effects of RSWT on bone tissue. Osteoblasts in culture flasks were studied by polymerase chain reaction after treatment with RSW (500 impulses, 0.05?mJ/mm2). An inhibited osteoblastogenesis was observed, with a statistically significant reduction in type 1 collagen, osterix, bone sialoprotein and receptor activator NF kappa ligand expression at 24 and 48?h, of osteocalcin at 24, 48 and 72?h, and osteopontin at 48 and 72?h. These findings show that RSWT is not indicated for treatment of delayed fracture union, pseudoarthrosis, and complex regional pain syndrome. The observed reduction in the receptor activator of nuclear factor-kB ligand/osteoprotegerin ratio suggests that it has an inhibiting effect on osteoclastogenesis, which could make it a useful tool for applications in proliferative diseases.  相似文献   
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