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41.
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Fibrin as a cell carrier in cardiovascular tissue engineering applications   总被引:10,自引:0,他引:10  
In cardiovascular tissue engineering approaches, efficient seeding methods are essential. To achieve this and to save time, cells can be encapsulated in gels. Combining the advantages of a gel as a cell carrier with the advantages of a fiber-based scaffold, providing structural integrity to the developing tissue, might offer several advantages. In this study, seeding by using fibrin as a cell carrier is compared to the conventional static seeding method with regard to tissue development. Seeding with fibrin resulted in less loss of soluble collagen into the medium and a more mature extracellular matrix in a shorter period of time. The use of fibrin degradation inhibitors was shown to inhibit extracellular matrix formation, although it did not hamper cell proliferation. The use of fibrin as a cell carrier to seed cells into a fiber-based scaffold may represent a promising, timesaving approach in cardiovascular tissue engineering applications.  相似文献   
43.
Graduate medical education programs face new challenges as they seek to comply with the mandate from the Accreditation Council on Graduate Medical Education to demonstrate that they are teaching and assessing residents on the six core competencies. The authors describe a project designed as a collaborative venture between the American Academy of Allergy, Asthma, and Immunology (AAAAI) and the Center for Educational Outcomes at Dartmouth College (CEdO) to provide residency programs in allergy/immunology with resources for teaching and assessing the core competencies. The goal was to create a set of learning and assessment resources that maximized the content knowledge expertise provided by the AAAAI and the learning expertise provided by CEdO. A highly interactive, iterative process was used to create a set of Web-based modules. Bilateral communication, buy-in, and active involvement in the process were seen as crucial to the development of resources and their successful implementation. Approximately 18 months after the modules were made available to training program directors, 80% of the directors surveyed were aware of and had accessed the modules. The joint creation process used in this project, designed to be generally applicable across specialties, reveals how the burden of meeting new requirements can be decreased when experts in content knowledge and experts in learning collaborate.  相似文献   
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Wild-type (+B) and compound chromosome mutant(bB) Drosophila melanogaster larvae were tested in a U-maze. FreshDrosophila food or food and larvae were placed in each of the two goals (+B only in goal 1,bB in goal 2) and served as stimulus. Separate trials were conducted using +B andbB larvae to test for preference in the maze. Significantly more test larvae went to the arm of the maze containing their own strain as stimulus when (1) both goals contained larvae, (2) one goal contained homogenetic larvae and the other fresh food only, and (3) the goals contained biotic residues of stimulus larvae. The strength of the stimulus necessary to elicit the response differed for the two strains, the +B strain apparently being more sensitive. As the density of the stimulus larvae was increased, the choices of the test larvae became statistically nonsignificant and the number of larvae remaining in the starting arm of the maze increased. The data suggested that the strains of larvae utilized here have the capacity for olfactory discrimination.Part of this investigation was supported by National Institutes of Health Award 1 F 32 NS05155-01 CMS from the Institute of Neurological and Communicative Disorders and Stroke to A. P.  相似文献   
46.
Staining of 326 rectal mucosal biopsies from ulcerative colitis patients with peanut agglutinin (PNA), which binds to the T-blood group antigen and has been claimed to reflect a cancer-associated mucin alteration, showed highly significant direct associations with mucosal dysplasia (P less than 0.001), disease activity (P less than 0.001), and subsequent development of rectal cancer in a smaller series of patients (P = 0.005). Staining for normal colonic mucin by the Dolichos biflorus (DBA) lectin related significantly and inversely to dysplasia. Intense normal colon mucin staining by DBA related significantly (P less than 0.025) to long disease duration and to subsequent development of cancer (P = 0.02). The latter association is based on a small number of patients only and is not considered conclusive evidence, but may provide a link with goblet-cell hyperplasia. The authors conclude that although T-antigen expression relates to dysplasia, the findings of "false" positive and negative rates of 22 and 33 percent respectively, make it unlikely that staining of biopsy sections for the T-antigen by peanut agglutinin will contribute materially to routine assessment for dysplasia and cancer risk prediction in patients with ulcerative colitis.  相似文献   
47.
We aimed to report the implementation of a phenylketonuria (PKU) transition program and study the effects of follow-up with an adult team on metabolic control, adherence, and loss of follow-up. Fifty-five PKU patients were analysed in the study periods (SP): 2 years before (SP1) and after the beginning of adult care (SP2). Retrospective data on metabolic control and number of clinic appointments were collected for each SP, and protein intakes were analysed. In SP2, three patients (6%) were lost to follow-up. There was a small but statistically significant increase in median number of annual blood spots from SP1 to SP2: 11 (7–15) vs. 14 (7–20); p = 0.002. Mean ± SD of median blood Phe remained stable (525 ± 248 µmol/L vs. 552 ± 225 µmol/L; p = 0.100); median % of blood Phe < 480 µmol/L decreased (51 (4–96)% vs. 37 (5–85)%; p = 0.041) and median number of clinic appointments increased from SP1 to SP2: (5 (4–6) vs. 11 (8–13); p < 0.001). No significant differences were found regarding any parameter of protein intake. Our results suggest that the implementation of an adult service was successful as impact on metabolic control was limited and attendance remained high. Continuous dietetic care likely contributed to these results by keeping patients in follow-up and committed to treatment.  相似文献   
48.
An appropriate balanced diet and dietary patterns are important at every stage of life, but in the case of young patients with type 1 diabetes mellitus (T1DM), it is especially crucial during the COVID-19 pandemic. The aim of the study was to assess health and nutritional behaviors, mainly adherence to the Mediterranean diet (MD), during the second wave of the COVID-19 pandemic in Poland among women with T1DM, and to compare them with a healthy population. This survey (based on a questionnaire) was conducted in December 2020 and included 219 young women, healthy (n = 106) and with T1DM (n = 113), from northeast Poland. Over 30% of the study group admitted that they did not engage in any physical activity. A large proportion declared that their screen time was 5–7 h a day (48% in control and 40% in T1DM group). High intakes of sweet-beverages, sweets and red meat, but also low intakes of olive oil, fish and nuts were observed. The vast majority of participants (60% vs. 71%) were moderately adherent to the Mediterranean Diet Adherence Screener (MEDAS). The study demonstrated that despite the similarity between the behaviors of healthy people and those with T1DM, negative health and nutritional practices, such as low physical activity, long screen time, medium and high levels of stress and inappropriate eating habits were observed.  相似文献   
49.
In patients with phenylketonuria (PKU), treated by diet therapy only, evidence suggests that areal bone mineral density (BMDa) is within the normal clinical reference range but is below the population norm. Aims: To study longitudinal bone density, mass, and geometry over 36 months in children with PKU taking either amino acid (L-AA) or casein glycomacropeptide substitutes (CGMP-AA) as their main protein source. Methodology: A total of 48 subjects completed the study, 19 subjects in the L-AA group (median age 11.1, range 5–16 years) and 29 subjects in the CGMP-AA group (median age 8.3, range 5–16 years). The CGMP-AA was further divided into two groups, CGMP100 (median age 9.2, range 5–16 years) (n = 13), children taking CGMP-AA only and CGMP50 (median age 7.3, range 5–15 years) (n = 16), children taking a combination of CGMP-AA and L-AA. Dual X-ray absorptiometry (DXA) was measured at enrolment and 36 months, peripheral quantitative computer tomography (pQCT) at 36 months only, and serum blood and urine bone turnover markers (BTM) and blood bone biochemistry at enrolment, 6, 12, and 36 months. Results: No statistically significant differences were found between the three groups for DXA outcome parameters, i.e., BMDa (L2–L4 BMDa g/cm2), bone mineral apparent density (L2–L4 BMAD g/cm3) and total body less head BMDa (TBLH g/cm2). All blood biochemistry markers were within the reference ranges, and BTM showed active bone turnover with a trend for BTM to decrease with increasing age. Conclusions: Bone density was clinically normal, although the median z scores were below the population mean. BTM showed active bone turnover and blood biochemistry was within the reference ranges. There appeared to be no advantage to bone density, mass, or geometry from taking a macropeptide-based protein substitute as compared with L-AAs.  相似文献   
50.
We diagnosed tuberculosis in an illegally wild-captured pet ring-tailed lemur manifesting lethargy, anorexia, and cervical lymphadenopathy. Whole-genome sequencing confirmed the Mycobacterium tuberculosis isolate belonged to lineage 3 and harbored streptomycin resistance. We recommend reverse zoonosis prevention and determination of whether lemurs are able to maintain M. tuberculosis infection.  相似文献   
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