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41.
This study was designed to evaluate the osteointegration of HA-coated and uncoated titanium screws in the cortical bone of long-term (24 months) ovariectomized sheep (OVX group) compared to sham-aged sheep (Control group). At 12 weeks after implantation, the screws were tested biomechanically (extraction torque) and histomorphometrically (affinity index: AI) in both femoral and tibial diaphyses. Cancellous bone status was assessed by iliac crest biopsy. BMD of the L5 vertebra and a histomorphological study of the femoral and tibial shafts were performed to acquire data on cortical bone. A significant difference was found between the OVX and Control groups for BMD (p<0.0005), and a significant reduction in the cancellous bone area was observed in the OVX group. Femoral and tibial cortical bone parameters showed significant differences between the groups. The type of material selected (femurs: p<0.0005; tibiae: p<0.0005) and ovariectomy (femurs: p<0.005; tibiae: p<0.005) had a significant effect on the extraction torque. AI results were related to the presence or absence of ovariectomy (p<0.05) and strictly depended on the material implanted in the femur and tibia (p<0.0005). In conclusion, at implantation OVX sheep showed a significant loss of trabecular and cortical bone versus sham-aged sheep. The biomechanical and histomorphological results achieved suggest employing HA-coated screws in the presence of osteopenic cortical bone.  相似文献   
42.
BACKGROUND: Growing evidence documents the frequent co-morbidity between Obsessive Compulsive Disorder (OCD) and Bipolar Disorder (BP) in adults. The aim of the present study is to explore some clinical aspects of this interface in children and adolescents, as it appears in a setting of routine clinical practice. METHOD: The sample comprised 102 consecutively referred children and adolescents, both inpatients and outpatients, with BP, OCD or co-morbid BP-OCD during a 3-year period. The mean age was 14.2 (SD=3.2); 65 (63.7%) were males. Diagnoses and clinical features were collected by means of structured interview according to DSM-IV (DICA-R) and a rating scale for OCD (CY-BOCS). Clinical outcome was evaluated prospectively by means of clinical global impression (CGI) as part of routine clinical care, throughout the follow-up. RESULTS: Thirty-seven (36.3%) patients (21 males and 16 females) were diagnosed as BP, 35 (34.3%) patients (26 males and 9 females) were diagnosed as OCD and 30 (29.4%) patients (18 males and 12 females) were diagnosed as BP-OCD. BP II, was more frequent in the BP-OCD than in BP. When OCD was co-morbid with BP, age of onset was significantly earlier than in the 'pure' OCD patients. On the contrary, age of onset of BP was not affected by co-morbid OCD. According to CGI baseline scores, OCD patients were significantly less impaired than BP-OCD and BP patients, while the severity of the symptomatology was similar in the last two groups. Severity scores at the end of the follow-up were significantly higher in BP-OCD patients than in OCD patients. Patients with pure BP showed lower rates of panic disorder-agoraphobia than BP-OCD patients and higher rates of ADHD-conduct disorder. Pure OCD patients showed lower rates of ADHD and higher rates of Generalized Anxiety Disorder. The number of obsessions did not differentiate the two groups, whereas pure OCD patients showed significantly more compulsions. 'Other' obsessions-e.g., existential, philosophical, odd and/or superstitious-were significantly more frequent in BP-OCD than in pure OCD patients. Ordering compulsions were significantly more frequent in pure OCD patients. LIMITATIONS: Possible low reliability of children's and their parents' recall of past episodes of mental disorder. CONCLUSIONS: In a tertiary care center, co-morbidity between OCD and BP is a significant clinical problem affecting a large number of patients. The correct identification of OCD-bipolar co-morbidity has relevant clinical implications as far as other concomitant disorders, symptomatological features, course, complications, and treatment management and outcome are concerned.  相似文献   
43.
Immunomagnetic CD34+ cell selection (ICS) is a widely employed technology in autotransplant and allotransplant settings. When an haploidentical transplant is performed, a high dose of purified CD34+ cells together with efficient T and B cell depletion are required to minimize the risks of graft versus host disease (GVHD) and Epstein-Barr virus (EBV)-related lymphoma. To ameliorate the performances of the CliniMACS (Miltenyi Biotec) ICS device, we compared 73 ICS performed following the manufacturer's recommended platelet depletion versus 48 performed after adjunctive centrifugations to increase platelet depletion of the leukapheresis (LKF) product. A total of 121 ICS (from single or fractioned LKF products) were carried out on 93 LKF collected from 47 related healthy donors. A statistical significance in terms of CD34+ cell recovery (81.8% vs. 71.2%) was found in favor of the modified ICS procedure (p=0.0049) with a comparable stem cell purity and viability. The modification of the standard manufacturer's technique for increasing platelet depletion can further improve the recovery of stem cells with no influence on T and B cell depletion. These results demonstrate the negative influence exerted on CD34+ cell recovery by LKF platelet contamination.  相似文献   
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An international advisory group met at the National Institutes of Health in Bethesda, Maryland in 2017, to discuss a new classification system for the ectodermal dysplasias (EDs) that would integrate both clinical and molecular information. We propose the following, a working definition of the EDs building on previous classification systems and incorporating current approaches to diagnosis: EDs are genetic conditions affecting the development and/or homeostasis of two or more ectodermal derivatives, including hair, teeth, nails, and certain glands. Genetic variations in genes known to be associated with EDs that affect only one derivative of the ectoderm (attenuated phenotype) will be grouped as non‐syndromic traits of the causative gene (e.g., non‐syndromic hypodontia or missing teeth associated with pathogenic variants of EDA “ectodysplasin”). Information for categorization and cataloging includes the phenotypic features, Online Mendelian Inheritance in Man number, mode of inheritance, genetic alteration, major developmental pathways involved (e.g., EDA, WNT “wingless‐type,” TP63 “tumor protein p63”) or the components of complex molecular structures (e.g., connexins, keratins, cadherins).  相似文献   
46.
A new implant surface has been developed with the purpose of avoiding as much stress shielding as possible, and thus prolong the prosthesis lifespan. The aim of this study was to investigate the in vitro effect of this new ultra-high roughness and dense Titanium (Ti) surface (PG60, Ra = 74 microm) in comparison with medium (TI01, Ra = 18 microm) and high (TI60, Ra = 40 microm) roughness and open porous coatings; all the coatings were obtained by vacuum plasma spraying. MG63 osteoblast-like cells were seeded on the tested materials and polystyrene, as control, for 3 and 7 days. Cells proliferated on the material surfaces similarly to the control. Alkaline phosphatase activity had lower values for TI60 than TI01 (p < 0.0005) and PG60 (p < 0.005). Osteocalcin levels measured on TI60 were significantly (p < 0.0005) lower in comparison with TI01 and PG60 at 7 days. Procollagen-I synthesis reduced with increasing roughness and the lowest data was found for PG60. While at 3 days Transforming Growth Factor beta1 levels augmented with increasing roughness, at 7 days TI60, the high roughness surface, was significantly lower than PG60 (p < 0.005) and TI01 (p < 0.001). All tested materials showed significantly higher Interleukin-6 levels than those of polystyrene at both experimental times. Nitric Oxide activity on TI01 was significantly (p < 0.05) higher than on TI60 and polystyrene. In conclusion, the new ultra-high roughness and dense coating PG60 provided a good biological response, even though, at least in vitro, it behaved similarly to the coatings already used in orthopaedics.  相似文献   
47.
Altered circulating levels of free fatty acids (FFAs), namely short chain fatty acids (SCFAs), medium chain fatty acids (MCFAs), and long chain fatty acids (LCFAs), are associated with metabolic, gastrointestinal, and malignant diseases. Hence, we compared the serum FFA profile of patients with celiac disease (CD), adenomatous polyposis (AP), and colorectal cancer (CRC) to healthy controls (HC). We enrolled 44 patients (19 CRC, 9 AP, 16 CD) and 16 HC. We performed a quantitative FFA evaluation with the gas chromatography–mass spectrometry method (GC–MS), and we performed Dirichlet-multinomial regression in order to highlight disease-specific FFA signature. HC showed a different composition of FFAs than CRC, AP, and CD patients. Furthermore, the partial least squares discriminant analysis (PLS-DA) confirmed perfect overlap between the CRC and AP patients and separation of HC from the diseased groups. The Dirichlet-multinomial regression identified only strong positive association between CD and butyric acid. Moreover, CD patients showed significant interactions with age, BMI, and gender. In addition, among patients with the same age and BMI, being male compared to being female implies a decrease of the CD effect on the (log) prevalence of butyric acid in FFA composition. Our data support GC–MS as a suitable method for the concurrent analysis of circulating SCFAs, MCFAs, and LCFAs in different gastrointestinal diseases. Furthermore, and notably, we suggest for the first time that butyric acid could represent a potential biomarker for CD screening.  相似文献   
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49.
Influenza is a disease responsible for thousands of deaths every year. Although healthcare workers (HCWs) represent a way of contagion for patients, vaccination coverage among them is low. Mandatory vaccination has been proposed, but controversies remain. This systematic review and meta-analysis aimed to assess the acceptance of mandatory vaccination by HCWs, and to investigate associated characteristics. MEDLINE, Scopus, Embase, PsycInfo, CINAHL and Web of Science were used to search for studies assessing the topic. PRISMA statements were followed. Of the 13,457 univocal records found, 52 studies were included in the systematic review and 40 in the meta-analysis. The pooled proportion of HCWs accepting the policy was of 61% (95% CI: 53%- 68%) but with great heterogeneity between continents (from 54% in Europe to 69% in Asia) and in different professionals (from 40% in nurses to 80% in students). Vaccinated HCWs agreed more frequently with mandatory vaccination than non-vaccinated ones. More studies that consider mandatory vaccination acceptance as the main outcome are needed, but the results of this study confirm that in some settings the majority of HCWs favour mandatory vaccination. This, combined with effects that a flu epidemic could have if overlapped to pandemics with similar symptoms, requires renewed considerations on mandatory vaccination.  相似文献   
50.
Bombyx mori silk fibroin (SF) is a very versatile biopolymer due to its biocompatibility and exceptional mechanical properties which make possible its use as a functional material in several applications. SF can be modified with a large variety of chemical approaches which endow the material with tailored chemical–physical properties. Here, a systematic investigation of different routes is reported to graft long alkyl chains on SF based on both liquid- and solid-phase, aiming to modulate its hydrophobic behavior. The liquid phase method involves direct activation of SF tyrosine residues via diazo coupling and cycloaddition reactions, generating hydrophobic materials insoluble in any common solvent. The solid phase approach consists of the chemical modification of drop-casted SF films by esterification of hydroxyl groups of serine, threonine, and tyrosine SF residues with acyl chlorides of fatty acids. For the solid-state functionalization, a new class of hydrophobic pendant groups is synthesized, based on triple esters of gallic acid anhydrides, that are reacted with the biopolymer to further enhance its resulting hydrophobic features.  相似文献   
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