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51.
Ido Somekh Benjamin Marquardt Yanshan Liu Meino Rohlfs Sebastian Hollizeck Musa Karakukcu Ekrem Unal Ebru Yilmaz Turkan Patiroglu Murat Cansever Shirly Frizinsky Vicktoria Vishnvenskia-Dai Erez Rechavi Tali Stauber Amos J. Simon Atar Lev Christoph Klein Daniel Kotlarz Raz Somech 《Journal of clinical immunology》2018,38(6):711-711
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Amos S Gaikwad Rachel E Donohue M Tarek Elghetany Andrea M Sheehan Xinyan Y Lu Maria M Gramatges Kenneth L McClain Toni-Ann Mistretta Jyotinder N Punia Timothy J Moore Tatiana Goltsova Michael Cubbage Choladda V Curry 《International journal of clinical and experimental pathology》2014,7(9):6225-6230
Background: Precursor B acute lymphoblastic leukemia (B-ALL) is the most common cancer in children and overall, has an excellent prognosis. However, the Philadelphia chromosome translocation (Ph+), t(9;22)(q34;q11), is present in a small subset of patients and confers poor outcomes. CD25 (IL-2 receptor alpha chain) expression has been associated with Ph+ B-ALL in adults, but no similar study has been performed in pediatric B-ALL. Methods: A retrospective analysis of 221 consecutive pediatric patients with a diagnosis of B-ALL (blood and/or bone marrow) from 2009 to 2012 was performed to determine an association between Ph+ B-ALL and CD25 expression. A threshold of 25% was used to define positive cases for CD25 expression by flow cytometry. Results: There were 221 patients with a diagnosis of B-ALL ranging from 2 to 22 years (median, 6 years). Eight (3.6%) B-ALL patients were positive for the Philadelphia chromosome translocation (Ph+ B-ALL) and 213 were negative (Ph-negative B-ALL). CD25 expression was observed in 6 of 8 (75%) Ph+ B-ALL patients and 6 of 213 (2.8%) Ph-negative B-ALL patients. CD25 expression was significantly higher in Ph+ B-ALL compared to Ph-negative B-ALL, with median CD25 expression of 64% (range 0-93%) and 0.1% (range 0-91%), respectively (P ≤ 0.0002). Therefore, CD25 expression as a predictor of Ph+ B-ALL had 75% sensitivity, 97% specificity, 50% positive predictive value and 99% negative predictive value. Conclusions: CD25 expression is a specific and relatively sensitive marker for the identification of Ph+ B-ALL in the pediatric population. 相似文献
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Nolan TL Lapinsky DJ Talbot JN Indarte M Liu Y Manepalli S Geffert LM Amos ME Taylor PN Madura JD Surratt CK 《ACS chemical neuroscience》2011,2(9):544-552
Ligand virtual screening (VS) using the vestibular binding pocket of a 3-D monoamine transporter (MAT) computational model followed by in vitro pharmacology led to the identification of a human serotonin transporter (hSERT) inhibitor with modest affinity (hSERT K(i) = 284 nM). Structural comparison of this VS-elucidated compound, denoted MI-17, to known SERT ligands led to the rational design and synthesis of DJLDU-3-79, a molecular hybrid of MI-17 and dual SERT/5-HT(1A) receptor antagonist SSA-426. Relative to MI-17, DJLDU-3-79 displayed 7-fold improvement in hSERT binding affinity and a 3-fold increase in [(3)H]-serotonin uptake inhibition potency at hSERT/HEK cells. This hybrid compound displayed a hSERT:hDAT selectivity ratio of 50:1, and a hSERT:hNET (human norepinephrine transporter) ratio of >200:1. In mice, DJLDU-3-79 decreased immobility in the tail suspension test comparable to the SSRI fluvoxamine, suggesting that DJLDU-3-79 may possess antidepressant properties. This proof of concept study highlights MAT virtual screening as a powerful tool for identifying novel inhibitor chemotypes and chemical fragments for rational inhibitor design. 相似文献
56.
As of December 2015 there were 37 million persons living with HIV/AIDS (PLWHAs), 70% of whom are in sub-Saharan Africa. Ghana, which contributes a relatively small number to Africa’s HIV burden, has a generalised HIV epidemic. The current national prevalence is 1.47%. Agormanya, one of the HIV sentinel sites in the county and where this study was conducted, has current prevalence of 11.6%. This makes it critical to explore how persons infected with HIV manage their lives, especially in the midst of entrenched stigma and discrimination. However, available information on how PLWHAs in sub-Saharan Africa handle their day-to-day lives mostly dwell on food and nutrition. Thus, there is dearth of information on how PLWHAs in Ghana particularly handle the circumstances of their daily lives which are mostly coloured by their HIV-positive statuses, given their stigmatised identity. We explore how PLWHAs respond to the experiences and challenges of living with HIV/AIDS in Lower Manya Krobo, consistently most HIV-infected district in Ghana. Data were collected from 38 combined purposive and randomly selected HIV-positive persons in two leading hospitals (St Martins Depores Agormanya and Atua Government hospitals which provide specialised HIV care in the district. Using in-depth interviews, we studied how PLWHAs managed their routine livelihoods in the midst of extreme stigma. We combined the social capital and resilience theoretical frameworks to show that our respondents were mostly resilient and strategically mostly drew upon extended family social support to cope with their livelihood challenges. We recommend that community opinion leaders and other stakeholders sensitise community members in Lower Manya Krobo to better understand the mode of HIV infection and encourage/strengthen family and community cohesion and social support. 相似文献
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Arie Waldman MD PhD Rina Segal MD Israela Berdicevsky PhD Amos Gilhar MD 《International journal of dermatology》2010,49(2):149-157
Background The cellular immune system is the most dominant factor in curing acute dermatophytosis. However, the exact immune mechanisms involved in generating this defense are complex and still obscure. The aim of this study was to investigate the fungicidal mechanism of T cells in the normal population versus patients with chronic fungal infections. Methods Thirty patients were included in the study: 15 patients with chronic dermatophytosis and 15 normal healthy patients with a history of acute dermatophytosis. The procedures were performed as follows. 1) Proliferation and cytotoxic activity of lymphocytes cultured with various dermatophytes homogenate such as, Trichophyton rubrum, Trichophyton mentagrophytes and Microsporum gypseum. 2) CD4+ and CD8+ T cells were separated by magnetic beads before culture with fresh spores of either T. mentagrophytes or T. rubrum. 3) Routine histology and ultrastructural study were performed to illustrate the mode of activity of the T cells against the dermatophytes. Results The study showed that both CD4 and CD8 possess cytotoxic activity against dermatophytes. However, the results demonstrated a suppression of lymphocyte proliferation response and a significant lower cytotoxic effect in chronic patients. Ultra structure and histological evaluation of the culture of hyphae with CD4+ or CD8+ T cells showed more prominently destructive effects in the culture of cells that had been obtained from normal population than those of patients with long‐lasting fungal infections. Conclusion The study suggests a selective impairment of lymphocyte function against dermatophytes, in patients with chronic dermatophytoses. 相似文献
59.
We carried out a retrospective case control analysis to evaluate the outcome, and the need for treatment, of problems with atrioventricular conduction occurring during an acute attack of rheumatic fever, assessing the occurrence of second and third atrioventricular block versus first degree block. We reviewed and analysed the clinical, electrocardiographic and echocardiographic records of all children diagnosed in a single institute as having acute rheumatic fever during a period of seven consecutive years. During the period from October, 1994, through October, 2001, 65 children meeting the modified Jones criterions for acute rheumatic fever were hospitalized in the Soroka University Medical Center, Israel. First-degree atrioventricular block was identified in 72.3% of the children, and resolved with no specific treatment other than non-steroidal anti-inflammatory medications. Second-degree atrioventricular block of Mobitz type I, was observed in one child (1.5%), which progressed from first-degree block, and subsequently resolved. Complete atrioventricuar block was found in 3 children (4.6%), one progressing from Mobitz type I second-degree block, and two being seen as the first presentation. Of the three children with complete atrioventricular block, one patient was not treated, the second was treated with aspirin, and the final one with combined aspirin and steroids. The disturbances of conduction resolved in all three. We conclude that advanced atrioventricular block is rare during acute rheumatic fever. If occurring, block appears to be temporary, and resolves with conventional anti-inflammatory treatment. Specific treatment, such as insertion of a temporary pacemaker, should be considered only when syncope or clinical symptoms persist. 相似文献
60.
Mouse bone marrow (BM) was separated into low-density, lineage- negative, wheat germ agglutinin-positive (WGA+), Rhodamine-123 bright (Rhbright) or dim (Rhdim) cells to obtain populations that were highly enriched for committed progenitors (Rhbright cells) or for more primitive stem cells (Rhdim). When 2,500 Rhbright or Rhdim cells were seeded onto 6-week-old irradiated (20 Gy) long-term BM cultures (LTBMC), the nonadherent cell production from Rhbright cells was transient and ended after 5 weeks. Production from Rhdim cells did not begin until week 3, peaked at week 5, and ended at week 8, when the irradiated stroma seemed to fail. Termination of cell production from Rhdim cells did not occur in nonirradiated LTBMC from W41/Wv mice. During peak nonadherent cell production, 25% to 30% of the cells in the nonirradiated LTBMC from W41/Wv mice had donor cell markers. Two approaches were tested to try to enhance the proportion or number of donor cells. Addition of Origen-HGF at the time of seeding Rhdim cells caused a nonspecific increase in both host and donor cell production, but a specific increase in production of donor cells was obtained by seeding the cultures at 2 weeks rather than 6 weeks. Limiting dilution of Rhdim cells gave the same frequency of wells producing cells on both irradiated +/+ and nonirradiated W41/Wv or W/Wv cultures. 相似文献