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BackgroundAlthough acetabular dysplasia is a common etiology of osteoarthritis of the hip regardless of the history of developmental dysplasia of the hip (DDH), whether or not corrective surgeries are beneficial for the childhood asymptomatic acetabular dysplasia remains controversial due to a lack of evidence. We conducted a longitudinal study to compare the cartilaginous morphology on childhood magnetic resonance imaging (MRI) and the mature hip morphology of the same patient and to assess the predictive indicators for future acetabular dysplasia.MethodsA total of 92 unaffected hips (47 unilateral DDH and 45 unilateral Legg-Calvé-Perthes disease) were reviewed for X-ray and MRI findings on childhood (mean age: 6.0 years) and X-ray findings from a skeletally mature age with a mean follow-up period of 15.1 years. The following parameters were measured and compared: the immature-acetabular index (AI) and center edge angle (CE) on immature X-ray; the cartilage- and bone- AI, CE, Sharp and acetabular head index (AHI) on childhood MRI; and the mature-acetabular roof obliquity (ARO), CE, Sharp and AHI on skeletally mature X-ray. The prognostic factors on childhood MRI for acetabular dysplasia, defined by a CE of <20° on skeletally mature X-ray were also assessed.ResultsPositive correlations were shown between the cartilage-AI and mature-ARO (7.6°/6.3°; r = 0.44), the cartilage-CE and mature-CE (27.8°/28.0°; r = 0.62), the cartilage-Sharp and mature-Sharp (44.4°/41.8°; r = 0.52) and the cartilage-AHI and mature-AHI (78.7%/80.3%; r = 0.46). A multivariate analysis indicated cartilage-CE to be an independent predictor for acetabular dysplasia with a cut-off value of 22°. Children with a cartilage-CE <22° developed more frequently acetabular dysplasia compared to the others (52.4% vs. 1.4%).ConclusionsChildhood MRI findings are useful for the prediction of acetabular dysplasia without a DDH history. Children with a cartilage-CE ≥23° are likely to achieve a non-dysplastic hip without the need for surgical intervention.  相似文献   
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Melatonin (MEL) has been reported to enhance cognitive processes, making it a potential treatment for cognitive decline. However, the role of MEL’s metabolites, N1‐acetyl‐N2‐formyl‐5‐methoxykynuramine (AFMK) and N1‐acetyl‐5‐methoxykynuramine (AMK), in these effects are unknown. The current study directly investigated the acute effects of systemic MEL, AFMK, and AMK on novel object recognition. We also analyzed MEL, AFMK, and AMK levels in hippocampus and temporal lobe containing the perirhinal cortex following systemic MEL and AMK treatment. AMK administered post‐training had a more potent effect on object memory than MEL and AFMK. AMK was also able to rescue age‐associated declines in memory impairments when object memory was tested up to 4 days following training. Results from administering AMK at varying times around the training trial and the metabolism time course in brain tissue suggest that AMK’s memory‐enhancing effects reflect memory consolidation. Furthermore, inhibiting the MEL‐to‐AMK metabolic pathway disrupted object memory at 24 hours post‐training, suggesting that endogenous AMK might play an important role in long‐term memory formation. This is the first study to report that AMK facilitates long‐term object memory performance in mice, and that MEL crosses the blood‐brain barrier and is immediately converted to AMK in brain tissue. Overall, these results support AMK as a potential therapeutic agent to improve or prevent memory decline.  相似文献   
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BackgroundEpstein-Barr virus (EBV) is a member of the herpesvirus family that is known to ubiquitously infect people worldwide. However, the actual prevalence of EBV infection in diseased patients in Nigeria, remains unknown. This study was thus conducted to ascertain the true prevalence.MethodsA systematic review and meta-analysis of published data was conducted according to the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). Electronic databases including PubMed, Scopus, ScienceDirect, and Google Scholar were searched for studies reporting the occurrence of EBV infection among patients with established diseases. Studies were included if they assessed EBV infection in diseased patients in Nigeria. Data were extracted and subsequently analysed using R software. Funnel plot and Egger's regression test was used to assess publication bias, while JBI prevalence tool was used to assess study quality.ResultsA total of 13 studies covering 228 cases of EBV infection among 1157 diseased patients were included. Summary estimates were computed using random-effects model. The pooled prevalence of EBV infection was 20.3% (95% CI: 10.8–34.9, I2 ?= ?92.26, p ?< ?0.001). When stratified according to the type of disease, higher estimates were obtained for patients suffering from Kaposi's sarcoma (98.7%, 95% CI: 82.2–99.9) and Nasopharyngeal malignancy (85.7%, 95% CI: 70.0–93.9). A prevalence of 13.4% (95% CI: 6.0–27.4) and 12.2% (95% CI: 4.8–27.8) was derived for the most reported patient populations, lymphoma and HIV, respectively.ConclusionThis first meta-analysis on the prevalence of EBV among Nigerian patients suffering from various diseases reveals a prevalence that emphasises the need to routinely monitor EBV infection in all EBV-associated diseases in Nigeria.  相似文献   
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Double‐stranded RNA (dsRNA) sensors including TLR3, MDA5 and RIG‐I are expressed in epidermal keratinocytes and play an important immunological role by enhancing various innate and adaptive immune responses. Although the role of elevated extracellular calcium concentration in keratinocyte differentiation is well understood, the effect of high calcium on dsRNA sensors is not well studied. We investigated alterations in dsRNA sensor expression and antiviral activity induced by a high extracellular concentration of calcium in epidermal keratinocytes. Normal human epidermal keratinocytes (NHEKs) were stimulated with high calcium and/or synthetic dsRNA, poly (I:C). TLR3, IFIH1 (MDA5) and DDX58 (RIG‐I) expression were measured via qPCR, and IFN‐β and human beta‐defensin 2 (HBD2) levels were measured using ELISA. TLR3 localization was evaluated with immunocytofluorescence. Antiviral activity was quantified with virus plaque assays using herpes simplex virus type 1 (HSV‐1). High calcium significantly upregulated mRNA expression of TLR3, IFIH1 and DDX58 in NHEKs. In addition, high calcium significantly enhanced poly (I:C)‐induced anti‐HSV‐1 activity in NHEKs. The antiviral molecule HBD2 but not IFN‐β induction by poly (I:C) was enhanced by high calcium. Our findings indicate that high levels of extracellular calcium enhance the expression of dsRNA sensors and augment antiviral activity in epidermal keratinocytes.  相似文献   
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Neuroendocrine neoplasm (NEN) of the pancreas and gastrointestinal tract is infrequent but often produces hormones to cause distinct clinical features. Glucagon-like peptide-1 receptor (GLP1R) is a G-protein coupled receptor for GLP1, which is cleaved by dipeptidyl peptidase (DPP)-IV, a peptidase that regulates the activity of peptide hormones. Since these molecules are involved in the neuroendocrine function of NEN, they could serve molecular targets for diagnosis and therapy of NEN. However, the expressions of these molecules in NEN are not well studied. We therefore examined the expression of GLP1R and DPP-IV in 22 cases of pancreatic NEN (P-NEN) and 20 cases of gastrointestinal NEN (GI-NEN) by immunostaining. GLP1R was expressed in all eight insulinomas (100 %) but so in only four out of 14 cases (29 %) of non-insulinomas. In contrast to GLP1R, DPP-IV was detected in one out of eight insulinomas (13 %) and in 12 out of 14 cases (86 %) of non-insulinomas. In GI-NEN, GLP1R was negative in all 10 cases of the foregut NEN, whereas it was expressed in all three cases (100 %) of midgut NEN and four out of seven cases (57 %) of hindgut NEN. DPP-IV was expressed in five out of 10 cases (50 %) of the foregut NEN. The expression was detected in two out of three cases (67 %) of midgut NEN and in all seven cases (100 %) of hindgut NEN. In conclusion, we found distinct expression patterns of GLP1R and DPP-IV depending on the neuroendocrine cell types in P-NEN and the anatomical sites in GI-NEN.  相似文献   
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