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991.
Globoid cell leukodystrophy (GLD; also known as Krabbe disease) is an invariably fatal lysosomal storage disorder caused by mutations in the galactocerebrosidase (GALC) gene. Hematopoietic stem cell (HSC)-based gene therapy is being explored for GLD; however, we found that forced GALC expression was toxic to HSCs and early progenitors, highlighting the need for improved regulation of vector expression. We used a genetic reporter strategy based on lentiviral vectors to detect microRNA activity in hematopoietic cells at single-cell resolution. We report that miR-126 and miR-130a were expressed in HSCs and early progenitors from both mice and humans, but not in differentiated progeny. Moreover, repopulating HSCs could be purified solely on the basis of miRNA expression, providing a new method relevant for human HSC isolation. By incorporating miR-126 target sequences into a GALC-expressing vector, we suppressed GALC expression in HSCs while maintaining robust expression in mature hematopoietic cells. This approach protected HSCs from GALC toxicity and allowed successful treatment of a mouse GLD model, providing a rationale to explore HSC-based gene therapy for GLD.  相似文献   
992.
BACKGROUND: Dinoprostone vaginal insert has been compared to Dinoprostone cervical gel in few studies, whose cases presented different Bishop scores and gestational ages at admission, and various treatment strategies in control arms. The present study compares the vaginal insert to the cervical gel in patients with low Bishop score at term. METHODS: Prospective multicenter randomized trial, with parity-based randomization. Admission criteria: single pregnancy with Bishop score of 0-4, gestational age of 37-41 weeks, intact membranes, no previous cesarean section, no bleeding or abnormal cardiotocography at admission. RESULTS: Vaginal prostaglandins were required as a second-line induction procedure in 25% of study patients versus 47.1% of controls (p < 0.03, chi2). Study patients experienced shorter induction-to-delivery time (920 +/- 428 versus 1,266 +/- 740 min, p <0,01), with a mean difference of 5 h and 46 min between the groups. Even though patients that received vaginal insert showed a trend of increased incidence of abnormal cardiotocography during labor (12% versus 6.3%) and hyperkinetic labor (11.8% versus 2.1%), the incidence of cesarean sections (21.4% versus 21.6%), cesareans for fetal distress (12.5% versus 11.8%), and umbilical artery pH <7.10 (4.9% versus 2.5%) was comparable between the two groups. CONCLUSIONS: Dinoprostone vaginal insert is more efficient than cervical gel in promoting cervical priming and labor induction in low-Bishop-score patients at term. The vaginal insert placement seems to be safe for the mother and the newborn, although larger studies are required to investigate uterine hyperstimulation incidence.  相似文献   
993.
Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in some areas of the world. In most cases, HCC is diagnosed at a late stage. Therefore, the prognosis of patients with HCC is generally poor. The recommended screening strategy for patients with cirrhosis includes the determination of serum α-fetoprotein (AFP) levels and an abdominal ultrasound every 6 months to detect HCC at an earlier stage. AFP, however, is a marker characterized by poor sensitivity and specificity, and abdominal ultrasound is highly dependent on the operator's experience. In addition to AFP, Lens culinaris agglutinin-reactive AFP (AFP-L3), des-γ-carboxy prothrombin (DCP), glypican-3 (GPC-3), osteopontin (OPN), and several other biomarkers (such as squamous cell carcinoma antigen-immunoglobulin M complexes [SCCA-IgM], alpha-1-fucosidase [AFU], chromogranin A [CgA], human hepatocyte growth factor, insulin-like growth factor) have been proposed as markers for the early detection of HCC. For these markers, we describe the mechanisms of production, and their diagnostic and prognosis roles. None of them is optimal; however, when used together, their sensitivity in detecting HCC is increased. Recent research has shown that some biomarkers have mitogenic and migratory activities in the angiogenesis of HCC and are a factor of tumor growth.  相似文献   
994.
Aspirin causes gastroduodenal ulcers and complications. Food bioactive compounds could exert beneficial effects in the gastrointestinal tract. We evaluated whether apple polyphenol extract (APE) reduced aspirin-induced injury to the rat gastric mucosa. Rats were treated with APE (10(-4) m catechin equivalent) before oral aspirin (200 mg/kg). Cyclo-oxygenase-2 (COX-2), transforming growth factor-alpha (TGF alpha) and heparin-binding epidermal-growth-factor-like growth factor (HB-EGF) mRNA and protein expression were assessed by RT-PCR and Western blot analysis, respectively; malondialdehyde (MDA) was determined by HPLC; gastric secretion was evaluated in pylorus-ligated rats. APE decreased acute and chronic aspirin injury both macroscopically and microscopically (approximately 50 % decrease in lesion score; P < 0.05). Aspirin up-regulated mRNA and protein expression of COX-2 and HB-EGF, but not of TGF alpha; APE reduced aspirin-induced mRNA and protein over-expression of COX-2 and HB-EGF; aspirin significantly increased gastric MDA and this effect was counteracted by APE pre-treatment. APE did not significantly affect gastric acid secretion. In conclusion, APE reduces aspirin-induced gastric injury independently of acid inhibition. We speculate that APE might be of therapeutic use in the prophylaxis of aspirin-related gastropathy.  相似文献   
995.
Porokeratosis of Mibelli is an uncommon chronic disorder of epidermal keratinization that should be treated because it can undergo malignant change into epithelial tumors on the lesions. At the moment, it represents a therapeutic challenge for dermatologists because of the lack of standardized guidelines about the treatment. Herein, we report a case of classic porokeratosis of Mibelli treated with photodynamic therapy successfully.  相似文献   
996.
AIM: To study the geographical distribution of high thyroid-stimulating hormone (TSH) level in the Marche region (central Italy). METHODS: Data were drawn from the Register of Neonatal Screening for Congenital Hypothyroidism (CH) of the Marche region (Italy), located at the Child Neuropsychiatry Department of Civil Hospital in Fano (Marche, Italy). Data were analyzed by Ohno's method. RESULTS: The findings of this study show a nonuniform distribution of high TSH levels in the Marche region, with an evident gradient from North to South. CONCLUSIONS: It is not possible to provide a definitive interpretation of these findings, although the specialized literature suggests that a high level of TSH in neonates should be interpreted as a marker of insufficient iodine uptake. Other factors affecting TSH level are also taken into consideration.  相似文献   
997.
998.

Background  

Functionality, controllability and cosmetics are the key issues to be addressed in order to accomplish a successful functional substitution of the human hand by means of a prosthesis. Not only the prosthesis should duplicate the human hand in shape, functionality, sensorization, perception and sense of body-belonging, but it should also be controlled as the natural one, in the most intuitive and undemanding way. At present, prosthetic hands are controlled by means of non-invasive interfaces based on electromyography (EMG). Driving a multi degrees of freedom (DoF) hand for achieving hand dexterity implies to selectively modulate many different EMG signals in order to make each joint move independently, and this could require significant cognitive effort to the user.  相似文献   
999.
1000.
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