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The oxytocinase subfamily of M1 aminopeptidases plays an important role in processing and trimming of peptides for presentation on major histocompatibility (MHC) Class I molecules. Several large-scale genomic studies have identified association of members of this family of enzymes, most notably ERAP1 and ERAP2, with immune-mediated diseases including ankylosing spondylitis, psoriasis and birdshot chorioretinopathy. Much is now known about the genetics of these enzymes and how genetic variants alter their function, but how these variants contribute to disease remains largely unresolved. Here we discuss what is known about their structure and function and highlight some of the knowledge gaps that affect development of drugs targeting these enzymes.  相似文献   
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Immunologic Research - The impairment of regulatory T cells (Tregs) is a characteristic feature of autoimmune hepatitis (AIH), and the degradation of tryptophan (Trp) to kynurenine (Kyn), by gamma...  相似文献   
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BackgroundThere is a lack of objective dynamic knee joint control measures that can be related to the status of the anterior cruciate ligament (ACL). The purpose of this study was to introduce two novel measures and apply a third to determine how dynamic knee joint control changes in relation to ACL status during dynamic movements.MethodsTwenty patients (13 male) were tested pre- (ACLd) and 10-months post- (ACLr) ACL reconstructive surgery and matched to an uninjured participant (CON). Kinetic and kinematic data were synchronously recorded with a force platform and motion capture system. Three objective control measures including dynamic angular stiffness, knee joint center excursion (KJCE), and knee joint center boundary (KJCB) were assessed for each participant when completing the side cut and hop tasks.ResultsDuring the side cut, stiffness was found to be significantly lower in ACLd (0.06 ± 0.01 Nm/kg/°) and ACLr (0.07 ± 0.02 Nm/kg/°) compared to CON (0.08 ± 0.02 Nm/kg/°), while there were no differences in stiffness during the hop. No significant differences were observed in the KJCE during the side cut, while KJCE was significantly greater (p = 0.006) during the hop in CON compared to the ACLd. There were no differences in KJCB.ConclusionsThese high-functioning ACL injured in both ACLd and ACLr phases, aside from reduced stiffness, were able to complete both tasks with similar dynamic control as the CON. Although improvements in self-perceived control between ACLd and ACLr have been observed, this lack of improvement in objective control demonstrates a gap between a patient's self-efficacy and the level of control.  相似文献   
75.
A series of donor‐acceptor (D‐A) π‐conjugated polymers, based on indacenodithienothiophene (IDTT) as an electron‐donating unit and quinoxaline as an electron‐deficient moiety, are synthesized via a Pd‐catalyzed Stille cross‐coupling polymerization. Molecular characteristics, photovoltaic parameters, and optoelectronic properties are examined through structural differences corresponding to thienyl versus phenyl side group substitutions on the IDTT and the non‐fluorinated versus the monofluoro quinoxaline derivatives. One of the most important outcome is that the power conversion efficiency (PCE) in the studied polymers is more device architecture dependent (conventional vs inverted) rather than chemical structure dependent. From single junction solar cells based on bulk heterojunction polymer:[6,6]‐phenyl‐C71‐butyric acid methyl ester (PC71BM) systems as the active layer, a maximum PCE of 5.33% has been achieved from the polymer containing the thienyl substituent on the IDTT and one fluorine atom on the quinoxaline. This demonstrates that finding the optimum molecular weight of ThIDTT‐QF or introducing the monofluoro‐quinoxaline in a regioregular motif in the polymer backbone significantly higher PCE can be expected versus the fully optimized high performance PhIDTT‐Q conjugated polymer.  相似文献   
76.
The karyotype is a strong independent prognostic factor in myelodysplastic syndromes (MDS). Since the implementation of the new comprehensive cytogenetic scoring system for MDS, chromosome 7 anomalies are no longer generally assigned to poor risk features but are thoroughly separated. However, der(1;7)(q10;p10), hereinafter der(1;7), is merged into the group labeled “any other single” and belongs to the intermediate risk group, just by definition due to lack of adequate clinical data. The aim of our international collaborative was to clarify the “real” prognostic impact of der(1;7) on a homogenous and well‐documented data base. We performed detailed analysis of 63 MDS patients with isolated der(1;7) constituting the largest cohort hitherto reported. Furthermore, clinical data are compared with those of patients with isolated del(7q) and isolated monosomy 7. Median overall survival (OS) of patients with der(1;7) is 26 months (hazard ratio (HR) 0.91 for del(7q) vs der(1;7) and 2.53 for monosomy 7 vs der(1;7)). The der(1;7) is associated with profound thrombocytopenia most probably causing the reduced OS which is in striking contrast to the low risk for AML transformation (HR 3.89 for del(7q) vs der(1;7) and 5.88 for monosomy 7 vs der(1;7)). Molecular karyotyping indicates that der(1;7) is generated in a single step during mitosis and that a chromosomal imbalance rather than a single disrupted gene accounts for malignancy. Thus, the current cytogenetic scoring system assigning isolated der(1;7) to the intermediate risk group is now confirmed by a sufficient data set.  相似文献   
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Purpose

Potential roles of inherited and environmental risk factors in pathogenesis of Langerhans cell histiocytosis (LCH), a myeloid neoplastic disorder, are undefined. We therefore evaluated the role of parental and perinatal factors on the risk of this childhood cancer.

Methods

Information on LCH cases (n = 162) for the period 1995–2011 was obtained from the Texas Cancer Registry. Birth certificate controls were frequency-matched on year of birth at a ratio of 10:1 for the same period. Variables evaluated included parental age, race/ethnicity, size for gestational age, and birth order. Logistic regression was used to generate an adjusted odds ratio (aOR) and 95% confidence interval (CI) testing the association between each factor and LCH.

Results

Few perinatal or parental factors were associated with LCH risk, with the exception of race/ethnicity. Mothers of Hispanic ethnicity were more likely to have children who developed LCH compared to non-Hispanic whites (aOR: 1.51; 95% CI: 1.02–2.25). This risk increased when both parents were Hispanic (aOR: 1.80; 95% CI: 1.13–2.87). Non-Hispanic black mothers were suggested as less likely to give birth to offspring who developed LCH compared to non-Hispanic whites (aOR: 0.50; 95% CI: 0.24–1.02).

Conclusions

LCH is characterized by somatic mutations in MAPK pathway genes in myeloid precursors. Increased risk for LCH in children of Hispanic parents suggests potential impact of inherited factors on LCH pathogenesis.  相似文献   
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