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61.
Slager SL Skibola CF Di Bernardo MC Conde L Broderick P McDonnell SK Goldin LR Croft N Holroyd A Harris S Riby J Serie DJ Kay NE Call TG Bracci PM Halperin E Lanasa MC Cunningham JM Leis JF Morrison VA Spector LG Vachon CM Shanafelt TD Strom SS Camp NJ Weinberg JB Matutes E Caporaso NE Wade R Dyer MJ Dearden C Cerhan JR Catovsky D Houlston RS 《Blood》2012,120(4):843-846
We performed a meta-analysis of 3 genome-wide association studies to identify additional common variants influencing chronic lymphocytic leukemia (CLL) risk. The discovery phase was composed of genome-wide association study data from 1121 cases and 3745 controls. Replication analysis was performed in 861 cases and 2033 controls. We identified a novel CLL risk locus at 6p21.33 (rs210142; intronic to the BAK1 gene, BCL2 antagonist killer 1; P = 9.47 × 10(-16)). A strong relationship between risk genotype and reduced BAK1 expression was shown in lymphoblastoid cell lines. This finding provides additional support for polygenic inheritance to CLL and provides further insight into the biologic basis of disease development. 相似文献
62.
Croft AP Situnayake D Khair O Giovanni G Carruthers D Sivaguru A Gordon C 《Clinical rheumatology》2012,31(6):1013-1018
Chronic progressive multisystem granulomatous disease is seen in 10-30% of patients with sarcoidosis and can result in end organ damage. Corticosteroids are the mainstay of treatment with the addition of cytotoxic agents in severe cases. Some patients are refractory to such treatment and, therefore, management is a challenge. There is currently limited evidence for biological agents such as infliximab, a monoclonal anti-tumor necrosis factor-α antibody in the treatment of multisystem sarcoidosis. We report outcomes of three patients with extensive multisystem sarcoidosis refractory to conventional treatment and treated at our center. Clinical assessment and radiographic imaging were used to assess the response to infliximab treatment. Infliximab therapy induced clinical remission in all three patients, and this clinical response correlated with radiographic evidence of the resolution of granulomatous disease. Serum ACE level was reduced in all cases, and daily steroid dosage was reduced. We propose that infliximab can be an effective treatment in patients with multisystem complex sarcoidosis refractory to conventional drug therapy and can result in sustained clinical remission. Our experience supports the urgent need for randomized controlled clinical trials of anti-TNF therapy in refractory systemic sarcoidosis. 相似文献
63.
M. P. Powar P. Martin A. R. Croft A. Walsh D. Petersen A. R. L. Stevenson J. W. Lumley R. W. Stitz G. L. Radford‐Smith D. A. Clark 《Colorectal disease》2013,15(3):374-379
Aim The advent of rescue medical therapy (cyclosporin or infliximab) and laparoscopic surgery has shifted the paradigm in managing steroid refractory acute severe ulcerative colitis (ASUC). We investigated prospectively the impact of rescue therapy on timing and postoperative complications of urgent colectomy and subsequent restorative surgery for steroid refractory ASUC. Method All consecutive presentations of steroid refractory ASUC at the Royal Brisbane Hospital (1996–2009) were entered in the study. Data collated included demographics, clinical and laboratory parameters on admission, medical therapy and operative and postoperative details. Steroid refractory ASUC patients undergoing immediate colectomy were compared with those failing rescue therapy and requiring same admission colectomy. Results Of 108 steroid refractory ASUC presentations, 19 (18%) received intravenous steroids only and proceeded directly to colectomy. Rescue medical therapy was instituted in 89 (82%) patients with 30 (34%) failing to respond and proceeding to colectomy. There was no significant difference in the median time from admission to colectomy for rescue therapy compared with steroid‐only cases (12 vs 10 days, P = 0.70) or 30‐day complication rates (27%vs 47%, P = 0.22). The interval from colectomy to a subsequent restorative procedure was significantly longer for patients who failed rescue therapy (12 vs 5 months, P = 0.02). Furthermore 30‐day complications following pouch surgery were significantly higher in patients who failed rescue therapy (32%vs 0%, P = 0.01). Conclusion Rescue therapy in steroid refractory ASUC is not related to delay in urgent colectomy or increased post‐colectomy complications. 相似文献
64.
Tirado CA Meloni-Ehrig AM Edwards T Scheerle J Burks K Repetti C Christacos NC Kelly JC Greenberg J Murphy C Croft CD Heritage D Mowrey PN 《Cancer Genetics and Cytogenetics》2007,174(2):166-169
We report the chromosomal findings in a 4-year-old female with precursor B-cell acute lymphoblastic leukemia (ALL). The diagnostic karyotype showed an isochromosome 7q, i(7)(q10), as well as questionable rearrangements on 9p and 11q. Fluorescence in situ hybridization (FISH) studies on both interphase and metaphase cells using the MLL "break-apart" and the centromeric chromosome 4 probes were instrumental in the characterization of an MLL gene rearrangement, which was cryptic by conventional cytogenetic analysis. Specifically, the FISH pattern was consistent with an insertion of the 5' region of the MLL gene into chromosome 4 at band q21, most likely a variant t(4;11)(q21;q23). This is the second case of FISH detection of an ins(4;11) in ALL. Our case exemplifies the importance of FISH in the further characterization of precursor B-cell ALL cases without any apparent prognostically significant chromosomal abnormalities. 相似文献
65.
Cooperation between CD4 and CD8 T cells for anti-tumor activity is enhanced by OX40 signals 总被引:3,自引:0,他引:3
The relative contribution of OX40 (CD134) to priming of CD8 T cells in complex systems where CD4 and CD8 cells respond and cooperate together is not clear. We previously found that OX40 expressed on tumor-reactive CD8 T cells controls their initial persistence when adoptively transferred in vivo and is required for delayed tumor growth. We now show that exogenous stimulation of OX40 with agonist antibody augments its ability to suppress the growth of new as well as established tumors, correlating with marked expansion of adoptively transferred CD8 T cells. Concomitantly, anti-OX40 strongly enhanced the number of tumor antigen-reactive CD4 T cells. Moreover, the augmented accumulation of CD8 T cells was prevented in animals lacking MHC class II or depleted of CD4 cells and did not occur in OX40-deficient animals receiving wild-type CD8 cells, demonstrating that non-CD8 cells are the major target of OX40 signals. These results suggest that while OX40 signaling to a CD8 T cell can control its expansion, OX40 expressed on non-CD8 cells strongly influences CD8 priming and in vivo activity. OX40 therefore represents an important signal for allowing effective cooperation between CD4 and CD8 cells and for promoting cell interplay and tumor rejection where CD8 activity is limiting. 相似文献
66.
A CD8+ T cell immune evasion protein specific to Epstein-Barr virus and its close relatives in Old World primates 总被引:3,自引:0,他引:3 下载免费PDF全文
Hislop AD Ressing ME van Leeuwen D Pudney VA Horst D Koppers-Lalic D Croft NP Neefjes JJ Rickinson AB Wiertz EJ 《The Journal of experimental medicine》2007,204(8):1863-1873
gamma 1-Herpesviruses such as Epstein-Barr virus (EBV) have a unique ability to amplify virus loads in vivo through latent growth-transforming infection. Whether they, like alpha- and beta-herpesviruses, have been driven to actively evade immune detection of replicative (lytic) infection remains a moot point. We were prompted to readdress this question by recent work (Pudney, V.A., A.M. Leese, A.B. Rickinson, and A.D. Hislop. 2005. J. Exp. Med. 201:349-360; Ressing, M.E., S.E. Keating, D. van Leeuwen, D. Koppers-Lalic, I.Y. Pappworth, E.J.H.J. Wiertz, and M. Rowe. 2005. J. Immunol. 174:6829-6838) showing that, as EBV-infected cells move through the lytic cycle, their susceptibility to EBV-specific CD8(+) T cell recognition falls dramatically, concomitant with a reductions in transporter associated with antigen processing (TAP) function and surface human histocompatibility leukocyte antigen (HLA) class I expression. Screening of genes that are unique to EBV and closely related gamma 1-herpesviruses of Old World primates identified an early EBV lytic cycle gene, BNLF2a, which efficiently blocks antigen-specific CD8(+) T cell recognition through HLA-A-, HLA-B-, and HLA-C-restricting alleles when expressed in target cells in vitro. The small (60-amino acid) BNLF2a protein mediated its effects through interacting with the TAP complex and inhibiting both its peptide- and ATP-binding functions. Furthermore, this targeting of the major histocompatibility complex class I pathway appears to be conserved among the BNLF2a homologues of Old World primate gamma 1-herpesviruses. Thus, even the acquisition of latent cycle genes endowing unique growth-transforming ability has not liberated these agents from evolutionary pressure to evade CD8(+) T cell control over virus replicative foci. 相似文献
67.
Vivas L Rattray L Stewart L Bongard E Robinson BL Peters W Croft SL 《Acta tropica》2008,105(3):222-228
Pyronaridine is a Mannich base anti-malarial with demonstrated efficacy against drug resistant Plasmodium falciparum, P. vivax, P. ovale and P. malariae. However, resistance to pyronaridine can develop quickly when it is used alone but can be considerably delayed when it is administered with artesunate in rodent malaria models. The aim of this study was to evaluate the efficacy of pyronaridine in combination with artesunate against P. falciparum in vitro and in rodent malaria models in vivo to support its clinical application. Pyronaridine showed consistently high levels of in vitro activity against a panel of six P. falciparum drug-sensitive and resistant strains (Geometric Mean IC50=2.24 nM, 95% CI=1.20-3.27). In vitro interactions between pyronaridine and artesunate showed a slight antagonistic trend, but in vivo compared to pyronaridine and artesunate administered alone, the 3:1 ratio of the combination, reduced the ED90 of artesunate by approximately 15.6-fold in a pyronaridine-resistant P. berghei line and by approximately 200-fold in an artesunate-resistant line of P. berghei. Complete cure rates were achieved with doses of the combination above or equal to 8 mg/kg per day against P. chabaudi AS. These results indicate that the combination had an enhanced effect over monotherapy and lower daily doses of artesunate could be used to obtain a curative effect. The data suggest that the combination of pyronaridine and artesunate should have potential in areas of multi-drug resistant malaria. 相似文献
68.
Objectives: To investigate two questions in a community based population of people with chronic shoulder pain. Firstly, does chronic pain lead to impaired psychological health over time? Secondly, how does restriction of daily activity influence pain perception and psychological health? Methods: Two postal surveys, two years apart, were carried out to identify a group of subjects with chronic shoulder pain. The first survey was sent to a random sample of adults (n=40026) registered with a primary care practice, and included a pain manikin, demographic information, and the Hospital Anxiety and Depression scale (HAD). The second survey was sent to those subjects who reported unilateral shoulder region pain in the first survey and it included a shoulder-specific disability scale, pain severity score, and the HAD. Results: 2606 (65.1%) people responded to the initial survey. Of these, 304 (11.7%) reported unilateral shoulder region pain at baseline. In the subsequent survey, there were 234 responders (83.3% adjusted response): 142 of these reported shoulder pain and formed our study group of "subjects with chronic shoulder pain". Within this group there was no significant change in psychological distress scores between baseline and follow up. Both the disability score and psychological distress scores correlated significantly with pain severity (disability v pain r=0.536, p<0.001; psychological distress v pain r=0.269, p=0.002). When the correlation between disability and pain severity was corrected for possible confounders, it remained significant (r=0.490, p<0.001). This was not the case for the correlation between psychological distress and pain (p>0.05). Disability was significantly correlated with psychological distress on univariate (r=0.445, p<0.001) and multivariate analysis (r=0.341, p=0.002). Conclusion: In those with chronic shoulder pain the relation between pain and psychological health seems to be linked to disability. Psychological distress was not explained by persistent pain itself. 相似文献
69.
Prevalence of heart disease and stroke risk factors in persons with prehypertension in the United States, 1999-2000 总被引:6,自引:0,他引:6
BACKGROUND: Recent guidelines classify persons with above-optimal blood pressure (BP) but not clinical hypertension as having prehypertension. METHODS: Data were analyzed for 3488 persons aged 20 years and older with BP measured in the 1999-2000 National Health and Nutrition Examination Survey. The prevalence of risk factors-above-normal (> or =200 mg/dL [> or =5.17 mmol/L]) and high (> or =240 mg/dL [> or =6.21 mmol/L]) total cholesterol levels, diabetes mellitus, current smoker, and overweight or obesity-and the number of risk factors present were compared among BP groups (normotension, prehypertension, and hypertension). Multivariable logistic regression included age, sex, and race/ethnicity as covariates. RESULTS: Overall, 39% of persons were normotensive,31% were prehypertensive, and 29% were hypertensive. The age-adjusted prevalence of prehypertension was greater in men (39.0%) than in women (23.1%). African Americans aged 20 to 39 years had a higher prevalence of prehypertension (37.4%) than whites (32.2%) and Mexican Americans (30.9%), but their prevalence was lower at older ages because of a higher prevalence of hypertension. The probabilities of above-normal cholesterol levels, overweight/obesity, and diabetes mellitus were greater for persons with prehypertension vs normotension, whereas the probability of currently smoking was lower. Persons with prehypertension were 1.65 times more likely to have at least 1 other adverse risk factor than were those with normotension (P<.001). Among participants with prehypertension, there were no significant race/ethnic or sex differences in the likelihood of having at least 1 other risk factor. CONCLUSIONS: The greater prevalence of risk factors in persons with prehypertension vs normotension suggests the continued need for early clinical detection and intervention of prehypertension and comprehensive preventive and public health efforts. 相似文献
70.
Costimulation of mast cells by 4-1BB, a member of the tumor necrosis factor receptor superfamily, with the high-affinity IgE receptor 总被引:1,自引:0,他引:1
Nishimoto H Lee SW Hong H Potter KG Maeda-Yamamoto M Kinoshita T Kawakami Y Mittler RS Kwon BS Ware CF Croft M Kawakami T 《Blood》2005,106(13):4241-4248
Mast cells are the major effector-cell type for immediate hypersensitivity and other forms of allergic reactions. Expression of 4-1BB, a member of the tumor necrosis factor receptor superfamily, is induced at mRNA and protein levels on stimulation through the high-affinity receptor for immunoglobulin E (IgE; FcepsilonRI). In this study, we present evidence that agonistic anti-4-1BB antibodies can enhance FcepsilonRI-induced cytokine production and secretion. Consistent with this, 4-1BB-deficient mast cells exhibit reduced degranulation and cytokine production on FcepsilonRI stimulation. Analysis of 4-1BB ligand (4-1BBL)-deficient cells supported this notion. As a potential mechanism for these defects, we identified a defect in Ca2+ flux induced by FcepsilonRI stimulation. The defective Ca2+ flux could be accounted for by the reduced activity of Lyn/Btk/phospholipase C-gamma2 pathway and constitutive interactions between 4-1BB and Lyn. Therefore, FcepsilonRI-inducible 4-1BB plays a costimulatory function together with FcepsilonRI stimulation. 相似文献