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91.
The major problem in skin grafting is that tissue-engineered skin grafts after their transplantation are initially entirely dependent on diffusion. Since this process is slow and inefficient, nutrients, growth factors, and oxygen will insufficiently be supplied and the regenerating graft will undergo a physiological crisis, resulting in scar-like dermal structures and shrinkage. The tissue-engineering of a vascular network in human dermo-epidermal skin substitutes (DESS) is a promising approach to overcome this limitation. Here we report, for the first time, on the use of the adipose stromal vascular fraction (SVF)-derived endothelial cell population to tissue-engineer DESS containing a highly efficient capillary plexus. To develop vascular networks in vitro, we employed optimized 3D fibrin or collagen type I hydrogel systems. Upon transplantation onto immune-deficient rats, these pre-formed vascular networks anastomosed to the recipient's vasculature within only four days. As a consequence, the neo-epidermis efficiently established tissue homeostasis, the dermis underwent almost no contraction, and showed sustained epidermal coverage in vivo. Overall, the here described rapid and efficient perfusion of SVF-based skin grafts opens new perspectives for the treatment of hitherto unmet clinical needs in burn/plastic surgery and dermatology.  相似文献   
92.
Behçet’s disease is a systemic disease characterized by oral aphthosis, genital ulcers, ocular lesions, gastrointestinal, musculoskeletal, neurological and major vessel involvement. Arterial involvement, aneurysms and arterial thrombosis have been reported in 1.5–3% of patients. In this case report, we present a patient with ulnar arterial aneurysm associated with Behçet’s disease.  相似文献   
93.
Inhibition of chemokines prevents intraperitoneal adhesions in mice   总被引:2,自引:0,他引:2  
BACKGROUND: The present study evaluates the efficacy of a broad-spectrumchemokine inhibitor, NR58-3.14.3, in the prevention of adhesionformation after i.p. surgery in mice. METHODS: A total of 110eight week old female Balb/c mice underwent laparotomy. Fortyanimals were randomly assigned to receive daily i.p. injectionsof either vehicle (control) or NR58-3.14.3. Time-course of adhesionformation was assessed. A titration of NR58-3.14.3 was conductedfor i.p. and s.c. administrations. The effectiveness of a singleintra-operative dose of NR58-3.14.3 was evaluated. Number, extent,location and type of adhesions were recorded. Immunohistochemistryof adhesions was done with leukocyte common antigen, CD45. RESULTS:Adhesion scores peaked on post-operative days 6–8. Onboth days 6 and 8, there were smaller adhesion size and lowercumulative adhesion scores in NR58-3.14.3-treated group. Moreover,on day 8, there were significantly fewer adhesions in NR58-3.14.3-treatedgroup compared to controls. The least effective dose for i.p.administration of NR58-3.14.3 was 0.45 mg/animal. Subcutaneousand single intra-operative i.p. administrations were also effectivein the prevention of i.p. adhesions. Although NR58-3.14.3 decreasedthe number of CD45+ inflammatory cells in the adhesions by 22.5%compared to control group, this was not significant. CONCLUSIONS:Our results show that this broad-spectrum chemokine inhibitorprevents post-operative adhesions in mice and may have a potentialclinical use.  相似文献   
94.

Purpose

The present study aimed to evaluate whether combining the magnetic-activated cell sorting (MACS) with density-gradient (DG) or swim-up (SU) sperm separation techniques can improve sperm selection to obtain higher quality spermatozoa.

Methods

Two commonly used sperm selection techniques, SU and DG, were compared to MACS combined with either SU or DG. Spermatozoa obtained from normozoospermic (n?=?10) and oligozoospermic (n?=?10) cases were grouped as SU, DG, SU+MACS, and DG+MACS followed by the analysis of sperm morphology, motility, DNA integrity, and the levels of Izumo-1 and PLCZ proteins.

Results

Although spermatozoa obtained by SU or DG when combined with MACS have improved aspects when compared to SU or DG alone, results did not reach a statistically significant level. Moreover, separation with MACS caused a significant loss in the numbers of total and rapid progressive spermatozoa.

Conclusions

Considering the cost/benefit ratio, MACS application together with traditional techniques may only be preferred in certain cases having higher concentrations of spermatozoa, but it does not seem to be an ideal and practical sperm selection technique for routine use.
  相似文献   
95.
Brucellosis produces a variety of nonspecific hematologic abnormalities. Hematologic complications of mild anemia and leukopenia have been frequently associated with acute brucellosis, but pancytopenia is less frequently seen. In this study, records of children with brucellosis aged under or equal to 16 years, admitted to Yuzuncu Yil University Hospital between 2004 and 2010, were analyzed retrospectively. Over this time period, 187 patients with brucellosis were diagnosed. Twenty-five (13.3%) of 187 patients had pancytopenia during admission to hospital. The diagnosis of brucellosis was confirmed by standard tube agglutination test in all patients; titers were 1:320 in 1 patient and 1:1280 in 24 patients. Blood culture was positive for Brucella melitensis in 3 patients (12%). Fever was the most common manifestation, followed by malaise, anorexia, sweating, and weight loss. Fever and splenomegaly were the common signs in most patients. In addition, arthritis was observed in 5 patients, and epistaxis, headache, and abdominal pain were observed in 3 patients. The common bone marrow aspiration findings consisted of increased megakaryocytes and hyperplasia of erythroid series, with a shift to the left of the granulocytic series. Histiocytic hyperplasia was observed in the bone marrow smear of 2 patients. Mild hemophagocytosis was observed in the bone marrow of 3 patients. All patients recovered completely, and their peripheral blood counts returned to normal by 2 to 6 weeks after antibiotic treatment of brucellosis. In conclusion, the authors would like to emphasize that brucellosis should be considered in the differential diagnosis of children with pancytopenia.  相似文献   
96.
97.
Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease with unknown etiology and pathogenesis. With high mortality risks, most of the IPF cases emerged after a damage of alveolar epithelium, where this situation stimulates the over expression of matrix components. Inflammatory process observed as a reaction to emerged damage. Prolidase as an iminodipeptidase significantly increased during the development of fibrosis. The aim of this study is to measure prolidase activity as a marker of treatment and diagnosis in an experimental lung fibrosis animal model. Thirty male Wistar rats randomly divided into three experimental groups, with ten rats in each group. Group 1, control group; group 2, bleomycin (BLM)-induced lung fibrosis group, and group 3, BLM-induced lung fibrosis treated with palosuran (urotensin-II receptor antagonist). For histopathology, the middle lobes of right lungs were embedded in paraffin, followed by fixation in 10?% buffered formalin, and evaluation of IPF was performed using the Ashcroft scoring method. Prolidase activity was determined by a photometric method based on the measurement of proline levels produced by prolidase. The fibrosis scores and the prolidase activity were significantly enhanced by BLM stimulation. The BLM + palosuran treatment decreased prolidase activity in group 3. There was a positive correlation between prolidase activity and fibrosis scores. Palosuran seems to be effective in the treatment of lung fibrosis, and prolidase activity can be used for the diagnosis and/or for management of the treatment. However, further clinical and experimental studies with animals and/or patients are needed to verify these conclusions.  相似文献   
98.
ObjectiveThe objective of this study was to report the first case of prenatal diagnosis of the fetal 20p13 microdeletion syndrome in the literature.Case reportThe mother was 31 years old and had a first trimester serum screening that indicated the fetus was at low risk. The prenatal ultrasound at 23 weeks of gestation showed mild ventriculomegaly (10.2 mm) and absent septum pellucidum. She underwent amniocentesis because of the abnormal imaging results. Karyotype analysis revealed normal results. Chromosome microarray analysis (CMA) was then performed to provide genetic analysis of the fetus and parents. CMA detected 317.902 kb deletion of 20p13 in fetus. Finally, pregnancy was terminated at 32 weeks of gestation.ConclusionThis study is the first to report the prenatal diagnosis of a 20p13 microdeletion syndrome. Our results further confirmed that genes in this region, including SOX12, NRSN2 are essential for normal fetal growth and TBC1D20 for normal brain development.  相似文献   
99.
100.
In this study, poly (methyl methacrylate–glycidyl methacrylate) [poly(MMA-GMA)] cryogels were prepared by radical cryocopolymerization of MMA with GMA as a functional comonomer. Reactive Green 19 dye was then attached to the cryogel by nucleophilic substitution reaction, and this dye-attached cryogel column was used for lysozyme adsorption. Characterization of the cryogel was performed by Fourier transform infrared spectroscopy, environmental scanning electron microscopy, Brunauer–Emmett–Teller, and energy dispersive X-ray analysis. Pore size of the cryogels was 15–30?μm and pores were interconnected structure. Attached amount of Reactive Green 19 to cryogel support was calculated as 106.25?μmol/g cryogel. Lysozyme adsorption studies were carried out by using a continuous system. It was found that the maximum amount of lysozyme adsorption (32?mg/g cryogel) obtained from experimental results was found to be approximately same with the calculated Langmuir adsorption capacity (33?mg/g cryogel). Desorption of adsorbed lysozyme was carried out by using 1.5?M NaCl in pH 4.5 acetate buffer, and desorption yield was found to be 97.4%. Cryogels were very stable, and it was found that there was no remarkable reduction in the adsorption capacity at the end of ten adsorption–desorption cycles. As a result, Reactive Green 19-attached cryogels have great advantages such as easy preparation, rapid adsorption, and desorption, being economic and allowing the direct separation of proteins.  相似文献   
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