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81.
Platelet-derived factors are biomaterials that might accelerate healing process in oral, maxillofacial, and several other applications. Release of specific factors by platelet concentrates is critical to achieving a successful outcome. Here, we have shown that platelet-rich fibrin (PRF) clots were beneficial sources of leukocytes, which may directly affect the release of chemokines and growth factors. When compared with the standard leukocyte-PRF (L-PRF), the experimental low-force modified procedure [defined as advanced-PRF (A-PRF)] entrapped the same content of viable leukocytes, released a similar amount of inflammatory cytokines, but secreted 3-, 1.6-, 3-, and 1.2-fold higher levels of Eotaxin, CCL5, platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF), respectively. A leukocyte-free scaffold, such as plasma rich in growth factors (PRGF), released only platelet-specific factors and, in particular, the F3 fraction, the richest in growth factors, secreted higher amount of CCL5 and PDGF compared to F1 and F2 fractions. In conclusion, different procedures and leukocyte content affect cytokine, chemokines, and growth factor release from platelet derivatives, which may be helpful in different clinical settings.  相似文献   
82.
Evaluation of Helicobacter species in inflammatory bowel disease   总被引:2,自引:0,他引:2  
BACKGROUND: Bacteria have been implicated in the pathogenesis of inflammatory bowel disease. Helicobacter species have been shown to cause colitis in animal models and have been identified in human diarrhoeal illness and Crohn's disease. AIM: To determine whether Helicobacter species are present in human inflammatory bowel disease tissue. METHODS: Thirty patients undergoing colonoscopy for clinical reasons were studied. Nine had Crohn's disease, 11 had ulcerative colitis and 10 had histologically normal colons. Tissue was snap-frozen at -70 degrees C. DNA was extracted and examined by five different polymerase chain reaction (PCR) assays that were either genus or species specific for Helicobacter. RESULTS: Analyses of colonic biopsies by two Helicobacter genus-specific PCR assays, two H. pylori-specific assays and a PCR assay designed to amplify fragments of 'H. heilmannii'-like organisms demonstrated that product was not generated by any test. Internal control PCR demonstrated that PCR results for the five assays were not negative due to the presence of residual substances inhibitory to PCR. CONCLUSIONS: Helicobacter species were not identified in this study, using multiple PCRs to eliminate the problems of non-specific cross-reaction. This suggests that Helicobacter species do not play a role in the pathogenesis of inflammatory bowel disease.  相似文献   
83.
84.
Recent studies have proposed that the bioelectrical response of glial cells, called astrocytes, currently represents a key target for neuroregenerative purposes. Here, we propose the fabrication of electrospun nanofibres containing gelatin and polyaniline (PANi) synthesized in the form of nano-needles (PnNs) as electrically conductive scaffolds to support the growth and functionalities of primary astrocytes. We report a fine control of the morphological features in terms of fibre size and spatial distribution and fibre patterning, i.e. random or aligned fibre organization, as revealed by SEM- and TEM-supported image analysis. We demonstrate that the peculiar morphological properties of fibres – i.e., the fibre size scale and alignment – drive the adhesion, proliferation, and functional properties of primary cortical astrocytes. In addition, the gradual transmission of biochemical and biophysical signals due to the presence of PnNs combined with the presence of gelatin results in a permissive and guiding environment for astrocytes. Accordingly, the functional properties of astrocytes measured via cell patch-clamp experiments reveal that PnNs do not alter the bioelectrical properties of resting astrocytes, thus setting the scene for the use of PnN-loaded nanofibres as bioconductive platforms for interfacing astrocytes and controlling their bioelectrical properties.

The presence of PnNs into electrospun fibres contributes to support in vitro functionalities of astrocytes.  相似文献   
85.
86.
In search for novel T-cell immunogens involved in protection against invasive meningococcal disease, we screened fractionated proteins of Neisseria meningitidis (strain SD, B:15:P1.16) by using peripheral blood mononuclear cells (PBMCs) and specific T-cell lines obtained from normal individuals and patients convalescing from N. meningitidis infection. Proteins of iron-depleted meningococci produced higher PBMC proliferation indices than proteins of iron-replete organisms, indicating that iron-regulated proteins are T-cell immunogens. Insoluble proteins of the iron-depleted cells, which produced better T-cell stimulation than soluble ones, were fractionated by using sodium dodecyl sulfate-polyacrylamide gels and recovered as five fractions (F1 to F5) corresponding to decreasing molecular weight ranges. The proteins were purified (by elution and precipitation) or electroblotted onto nitrocellulose membranes (dissolved and precipitated) before use in further T-cell proliferation assays. One of the fractions (F1), containing high-molecular-mass proteins (>130 kDa), consistently showed the strongest T-cell proliferation responses in all of the T-cell lines examined. F1 proteins were subdivided into four smaller fractions (F1A to F1D) which were reexamined in T-cell proliferation assays, and F1C induced the strongest responses in patients' T-cell lines. Rabbit polyclonal antibodies to F1C components were used to screen a genomic expression library of N. meningitidis. Two major clones (C1 and C24) of recombinant meningococcal DNA were identified and fully sequenced. Sequence analysis showed that C24 (1,874 bp) consisted of a single open reading frame (ORF), which was included in clone C1 (2, 778 bp). The strong CD4(+) T-cell-stimulating effect of the polypeptide product of this ORF (named TspA) was confirmed, using a patient T-cell line. Immunogenicity for B cells was confirmed by showing that convalescent patients' serum antibodies recognized TspA on Western blots. Additional genetic sequence downstream of C24 was obtained from the meningococcal genomic sequence database (Sanger Centre), enabling the whole gene of 2,761 bp to be reconstructed. The DNA and deduced amino acid sequence data for tspA failed to show significant homology to any known gene, except for a corresponding (uncharacterized) gene in Neisseria gonorrhoeae genome sequences, suggesting that tspA is unique to the genus Neisseria. The DNA and deduced amino acid sequence of the second ORF of clone C1 showed significant homology to gloA, encoding glyoxalase I enzyme, of Salmonella typhimurium and Escherichia coli. Thus, we have identified a novel neisserial protein (TspA) which proved to be a strong CD4(+) T-cell- and B-cell-stimulating immunogen with potential as a possible vaccine candidate.  相似文献   
87.
Background: Refeeding syndrome (RS) is a neglected, potentially fatal syndrome that occurs in malnourished patients undergoing rapid nutritional replenishment after a period of fasting. The American Society for Parenteral and Enteral Nutrition (ASPEN) recently released new criteria for RS risk and diagnosis. Real-life data on its incidence are still limited. Methods: We consecutively enrolled patients admitted to the Internal Medicine and Gastroenterology Unit of our center. The RS risk prevalence and incidence of RS were evaluated according to ASPEN. The length of stay (LOS), mortality, and re-admission rate within 30 days were assessed. Results: Among 203 admitted patients, 98 (48.3%) were at risk of RS; RS occurred in 38 patients (18.7% of the entire cohort). Patients diagnosed with RS had a higher mean LOS (12.5 days ± 7.9) than those who were not diagnosed with RS (7.1 ± 4.2) (p < 0.0001). Nine patients (4.4%) died. Body mass index (OR 0.82; 95% CI 0.69–0.97), RS diagnosis (OR 10.1; 95% CI 2.4–42.6), and medical nutritional support within 48 h (OR 0.12; 95% CI 0.02–0.56) were associated with mortality. Conclusions: RS incidence is high among clinical wards, influencing clinical outcomes. Awareness among clinicians is necessary to identify patients at risk and to support those developing this syndrome.  相似文献   
88.
Our aim was to assess adherence to the Mediterranean diet in a group of 726 secondary school students (336 girls, 390 boys) who completed the web-based Medi-Lite questionnaire simultaneously, during school hours, at the “Istituto Professionale per l’Enogastronomia e l’Ospitalità Alberghiera Marco Polo” in Genoa, Italy. The mean adherence score was 9.28 ± 2.29, with significantly (p = 0.017) higher values in girls (9.5 ± 2.2) than boys (9.1 ± 2.4). As to the individual food components of the Medi-Lite score, 84% of students reported non-optimal consumption (i.e., the choice that yielded ≤ 1 point) of meat and meat products, and over 50% reported non-optimal consumption of vegetables, legumes, dairy products, and fish. Significant differences between girls and boys were observed for fruit (p = 0.003), cereals (p < 0.001), meat and meat products (p < 0.001), and dairy products (p = 0.003). By conducting a principal component analysis, we observed that Medi-Lite items on the consumption of some animal products (meat and meat products and dairy products) and some plant products (fruit, vegetables, and legumes) generated contrasting patterns of responses, denoting excessive consumption in the first case and underconsumption in the second. This result suggests the need for effective actions to promote healthy eating habits in young people.  相似文献   
89.
Background and purpose: Temporary discontinuation of natalizumab is sometimes considered as the observed risk of progressive multifocal leukoencephalopathy (PML) in patients with multiple sclerosis (MS). However, interruption of natalizumab may result in a re‐start of disease activity. Methods: In this prospective post‐marketing study, 23 patients with MS treated with natalizumab elected a trial of treatment interruption (90–150 days) because of safety concerns on the risk of developing PML. To reduce the risk of disease activity return, patients received monthly intravenous (i.v.) steroid pulses before natalizumab re‐start. Results: Despite the steroid coverage, seven patients (30.4%) had an active scan during the natalizumab interruption period; of these, four also had a concomitant clinical exacerbation. Conclusions: Our findings suggest that i.v. steroids are not currently recommendable as drug coverage during a scheduled treatment interruption period.  相似文献   
90.
Large Brunner's gland adenoma: Case report and literature review   总被引:3,自引:1,他引:2  
Brunner's gland adenoma(BGA)is a very rare benigntumour of the duodenum,which is usually asymptomaticand discovered incidentally at endoscopy.Occasionally,this lesion may be large,causing upper gastrointestinalhaemorrhage or intestinal obstruction.The case had alarge Brunner's gland adenoma,presenting melena thatwas managed by endoscopic excision.  相似文献   
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