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21.

Background:

Chondral lesions of the knee are commonly found during arthroscopic partial meniscectomy. The literature advises against arthroscopic medial meniscectomy in the presence of advanced chondral derangement because of unfavorable outcome. Recent studies have shown an association between obesity and chondropathy in patients with meniscal tears. The aim of this study was to assess whether body mass index (BMI) correlates with the severity of chondral lesions in patients with isolated medial meniscus tears (i.e. without ligamentous or lateral meniscal injury).

Materials and Methods:

837 knee arthroscopies were performed in a regional referral center of arthroscopic surgery between January 2011 and December 2012. Of these 168 (109 males, 59 females) patients with no axial knee deformity and no radiological signs of osteoarthritis who have had arthroscopic debridement for isolated torn medial meniscus were included in the study. The correlation between different demographic factors and the level of chondral damage reported at surgery was evaluated. The mean age of patient was 50 years (range 13-82 years) and an average BMI was 28.2 kg/m2 (range17.5-42.5 kg/m2).

Results:

Overall, regression analysis showed both age and BMI to be linearly correlated to chondral score (r = 0.53, P < 0.04); however, there were no advanced chondral lesions found in patients younger than 40 years of age and all severe lesions were at age 50 years or more. Therefore, further analysis was performed for age subgroups: patients were grouped as younger than 40, between the age of 40 and 50 (middle age) and older than 50 years. The BMI was linearly correlated to the severity of chondral score exclusively in the middle aged group (i.e. 40-50 years old). There was no correlation between activity level and chondral damage. Women had worse chondral lesions than men in all age groups.

Conclusion:

Higher BMI in middle aged patients with isolated medial meniscus tears and unremarkable radiographs may predict more advanced chondral lesions at arthroscopy.  相似文献   
22.
The aim of the present study was to determine the diagnostic accuracy of ultrasonically guided fine-needle aspiration for liver lesions detected by ultrasound scan. A total of 142 aspirations were carried out in 129 patients with unifocal or multifocal liver lesions suspected of malignancy. The aspiration was made with a 22-gauge needle, guided by ultrasound. Based on histological, cytological, and clinical findings, final diagnoses were reached in 123 patients, 96 of whom had malignant liver disease and 27 benign liver disease. Among the 96 patients with malignant liver disease, the cytological findings revealed malignancy in 78 patients (81.3%) and suspected malignancy in five patients (5.1%), but failed to demonstrate malignancy in 13 patients (13.3%). Among 27 patients with benign liver disease, all the cytological findings indicated benignancy. The overall sensitivity, specificity, and positive and negative predictive values for cytological findings were 86.5%, 100%, 100%, and 76.9%, respectively. The diagnostic accuracy of ultrasonically guided fine-needle aspiration was 89.4%. In one patient with incipient chronic disseminated intravascular coagulation, a fatal intraperitoneal bleeding complicated the procedure. We conclude that ultrasonically guided FNA for cytologic diagnosis of liver lesions is highly accurate and is only rarely associated with fatal complication.  相似文献   
23.
The Steroidogenic Acute Regulatory (StAR) protein is a mitochondrial protein required for the transport of cholesterol substrate to the P450scc enzyme located in the inner mitochondrial membranes of steroid producing cells. This study suggests that the acute regulation of the rodent StAR gene in the ovary is mediated by two factors, C/EBPbeta and GATA-4. Once translated, the StAR precursor protein is either imported into the mitochondria, or it is rapidly degraded in the cytosol. We predicted that in order to perpetuate StAR activity cycles, imported StAR should turn over rapidly to avoid a potentially harmful accumulation of the protein in sub-mitochondrial compartments. Pulse-chase experiments in metabolically labeled cells showed that: (a) the turnover rate of mature mitochondrial StAR protein (30 kDa) is much faster (t(1/2) = 4-5 h) than that of other mitochondrial proteins; (b) dissipation of the inner membrane potential (-delta psi) by carbonyl cyanide m-chlorophenylhydrazone (mCCCP) accelerates the mitochondrial degradation of StAR; (c) unexpectedly, the mitochondrial degradation of StAR is inhibited by MG132 and lactacystin, but not by epoxomicin. Furthermore, StAR degradation becomes inhibitor-resistant two hours after import. Therefore, these studies suggest a bi-phasic route of StAR turnover in the mitochondria. Shortly after import, StAR is degraded by inhibitor-sensitive protease(s) (phase I), whereas at later times, StAR turnover proceeds to completion through an MG132-resistant proteolytic activity (phase II). Collectively, this study defines StAR as a unique protein that can authentically be used to probe multiple proteolytic activities in mammalian mitochondria.  相似文献   
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Foveal hypoplasia, always accompanied by nystagmus, is found as part of the clinical spectrum of various eye disorders such as aniridia, albinism and achromatopsia. However, the molecular basis of isolated autosomal recessive foveal hypoplasia is yet unknown. Individuals of apparently unrelated non consanguineous Israeli families of Jewish Indian (Mumbai) ancestry presented with isolated foveal hypoplasia associated with congenital nystagmus and reduced visual acuity. Genome-wide homozygosity mapping followed by fine mapping defined a 830 Kb disease-associated locus (LOD score 3.5). Whole-exome sequencing identified a single missense mutation in the homozygosity region: c.95T>G, p.(Ile32Ser), in a conserved amino acid within the first predicted transmembrane domain of SLC38A8. The mutation fully segregated with the disease-associated phenotype, demonstrating an ∼10% carrier rate in Mumbai Jews. SLC38A8 encodes a putative sodium-dependent amino-acid/proton antiporter, which we showed to be expressed solely in the eye. Thus, a homozygous SLC38A8 mutation likely underlies isolated foveal hypoplasia.  相似文献   
27.
The purpose of the current study was to establish measurement reliability in adults with Cerebral Palsy (CP), and to examine the feasibility and outcomes of an upper extremity strength training program (three times per week for 90 min each time). A control group design mixed with a prospective time series design for the intervention group was completed, including a pre-test, a post-test after a 12-week intervention period, and a follow-up in the intervention group after an additional 10-week period. Seventeen adults with CP with severe motor impairment took part in the study (10 in the intervention and seven in the control group). The test battery was comprised of wrist and hand dynamometry; dominant hand upper-extremity function measures (Jebsen Hand Function Test = JHFT, Minnesota Manual Dexterity Test = MMDT, and the Nine Hole Peg Test = NHPT); and activity of daily living with the Barthel Index.The results indicated that in both the control and the intervention groups, the strength tests exhibited good-to-excellent reliability during pre-test and post-test. The group comparison revealed that while in the pre-test no between-group differences existed, in the post-test the strength training group demonstrated significantly higher values in five out of eight strength measures, as well as in the MMDT. Discontinuing the program for eight weeks reversed the effects almost to baseline. In conclusion, the outcomes demonstrated the reliability of the assessments utilized in this study, as well as the feasibility of the strength training program, in adults with severe motor impairment due to CP.  相似文献   
28.
Abstract

Background: The aim of this study was to characterize human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS)-related knowledge and stigma among methadone maintenance treatment (MMT) patients and evaluate the contribution of an educational lecture in reducing risky behavior and unjustified overprotective behavior due to fear and stigma among MMT patients. Methods: Patients from an MMT clinic within a tertiary medical center were invited to an educational lecture on HIV/AIDS. Seventy participants (of current 330) were chosen by a random sample (December 2015), plus at-risk patients and HIV patients. Attendee compliance and change in scores of questionnaires on knowledge (modified HIV-K-Q-22) and on sexual and injection behaviors were studied. Results: Forty-six patients (65.7% compliance) attended the lecture, and their knowledge and behavior scores improved 2?weeks post-lecture (knowledge: from 14.2?±?3 to 19.0?±?2.2 [P?<?.0005], sexual behavior: from 12.1?±?2.9 to 8.8?±?3.0 [P?<?.0005], and injection behavior: from 7.3?±?6.2 to 0.2?±?1.3 [P?<?.0005]). The unjustified fear of proximity to HIV carriers reported by 50% attendees fell to 35% post-lecture. Eight months post-lecture, the scores on knowledge and risky behavior of 21 randomly chosen attendees were still better than pre-lecture scores (knowledge: 15.4?±?2.3 vs. 17.2?±?1.8 [paired t test, P?=?.001], sexual behavior: 13.2?±?2.3 vs. 9.7?±?2.9 [P?<?.0005], and injection behavior: 9.3?±?5.6 vs. 2.8?±?3.1 [P?<?.0005]). Drug abuse and treatment adherence were not related to intervention and to risky behavior. Conclusions: More knowledge, less fear, and less risky behavior immediately and at 8?months post-lecture reflect the success and importance of the educational intervention. Future efforts are needed in order to reduce ignorance and fear associated with HIV/AIDS.  相似文献   
29.
Postpartum depression (PPD) is a severe disorder that adversely impacts both mothers and infants. It is associated with significant morbidity and mortality and reported prevalence is 11.5% (Ko, Rockhill, Tong, Morrow, & Farr. (2017). MMWR Morbidity and Mortality Weekly Report, 66(6), 153–158). Although PPD's fundamental pathophysiology remains to be fully illuminated, the influence of changes in perinatal hormones such as allopregnanolone (an endogenous progesterone metabolite) are most promising avenues of research. Conventional treatments for PPD are aligned with treatment strategies for depressive disorders. Brexanolone is a small molecule, neuroactive steroid GABAA receptor allosteric modulator consisting of synthetic allopregnanolone and a solubilizing agent. In early 2019, brexanolone received approval in the United States for the treatment of PPD. Brexanolone is only available through a restricted program and is costly. Animal models demonstrate that progesterone prevents depression-like behaviors. However, studies of progesterone's effects in women suffering from PPD are few and inconclusive. We hypothesize that orally dosed progesterone will increase concentrations of allopregnanolone in the central nervous system, which should relieve symptoms of PPD.  相似文献   
30.
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