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11.
Various natural and synthetic polymeric materials have been used as scaffold matrices for tissue-engineered skin. However, the commercially available skin replacement products pose problems of poor mechanical properties and immunological rejection. We have thus developed a film of 5 microm thickness, via biaxial stretching of poly(epsilon-caprolactone) (PCL), as a potential matrix for living skin replacements. The aim of this study was to evaluate the feasibility of using biaxially stretched PCL films as matrices for culturing human dermal fibroblasts. For this purpose, we cultured human dermal fibroblasts for 7 days on the films. Glass cover slips and polyurethane (PU) sheets were used as controls. The data from phase contrast light, confocal laser, and scanning electron microscopy suggested that biaxially stretched PCL films support the attachment and proliferation of human dermal fibroblasts. Thymidine-labeling results showed quantitatively that cell proliferation on the PCL films was superior to that on the PU samples. These results indicated that biaxially stretched PCL films supported the growth of human dermal fibroblasts and might have potential to be applied in tissue engineering a dermal equivalent or skin graft.  相似文献   
12.
BackgroundSevere acute respiratory syndrome (SARS) and coronavirus disease 2019 (COVID-19) are closely related. The effect of AKI on the clinical outcomes of these two conditions is unclear.MethodsThis retrospective, territory-wide cohort study used an electronic public healthcare database in Hong Kong to identify patients with SARS or COVID-19 by diagnosis codes, virologic results, or both. The primary endpoint was a composite of intensive care unit admission, use of invasive mechanical ventilation, and/or death.ResultsWe identified 1670 patients with SARS and 1040 patients with COVID-19 (median ages, 41 versus 35 years, respectively). Among patients with SARS, 26% met the primary endpoint versus 5.3% of those with COVID-19. Diabetes mellitus, abnormal liver function, and AKI were factors significantly associated with the primary endpoint among patients with either SARS or COVID-19. Among patients with SARS, 7.9%, 2.1%, and 3.7% developed stage 1, stage 2, and stage 3 AKI, respectively; among those with COVID-19, 6.6%, 0.4%, and 1.1% developed stage 1, stage 2, and stage 3 AKI, respectively. In both groups, factors significantly associated with AKI included diabetes mellitus and hypertension. Among patients with AKI, those with COVID-19 had a lower rate of major adverse clinical outcomes versus patients with SARS. Renal function recovery usually occurred within 30 days after an initial AKI event.ConclusionsAKI rates were higher among patients with SARS than those with COVID-19. AKI was associated with major adverse clinical outcomes for both diseases. Patients with diabetes mellitus and abnormal liver function were also at risk of developing severe consequences after SARS and COVID-19 infection.  相似文献   
13.
Individualized posttransplant immunosuppression is hampered by suboptimal monitoring strategies. To validate the utility of urinary CXCL10/Cr immune monitoring in children, we conducted a multicenter prospective observational study in children <21 years with serial and biopsy-associated urine samples (n = 97). Biopsies (n = 240) were categorized as normal (NOR), rejection (>i1t1; REJ), indeterminate (IND), BKV infection, and leukocyturia (LEU). An independent pediatric cohort of 180 urines was used for external validation. Ninety-seven patients aged 11.4 ± 5.5 years showed elevated urinary CXCL10/Cr in REJ (3.1, IQR 1.1, 16.4; P < .001) and BKV nephropathy (median = 5.6, IQR 1.3, 26.9; P < .001) vs. NOR (0.8, IQR 0.4, 1.5). The AUC for REJ vs. NOR was 0.76 (95% CI 0.66–0.86). Low (0.63) and high (4.08) CXCL10/Cr levels defined high sensitivity and specificity thresholds, respectively; validated against an independent sample set (AUC = 0.76, 95% CI 0.66–0.86). Serial urines anticipated REJ up to 4 weeks prior to biopsy and declined within 1 month following treatment. Elevated mean CXCL10/Cr was correlated with first-year eGFR decline (ρ = −0.37, P ≤ .001), particularly when persistently exceeding ≥4.08 (ratio = 0.81; P < .04). Useful thresholds for urinary CXCL10/Cr levels reproducibly define the risk of rejection, immune quiescence, and decline in allograft function for use in real-time clinical monitoring in children.  相似文献   
14.
This is a retrospective observational study of outcome of 11 cases of vaginal hysterectomy for undescended and enlarged uterus carried in University Hospital, Kuala Lumpur. The cases included relative contraindications such as 14 weeks size fibroids, severe obesity, previous Caesarean section and nulliparity. All the eight patients agreeable for prophylactic bilateral salpingoophorectomy had their ovaries removed. Operative time ranged from 1 hr 20 min to 2 hr 15 min. All patients were sent home within 48 hours of the operation. The excellent outcome of our initial experience highlights the known advantages of vaginal hysterectomy for undescended and enlarged uterus.  相似文献   
15.
A therapeutic strategy was designed to eliminate the humoral immune response to acetylcholine receptor (AChR) in ongoing experimental autoimmune myasthenia gravis (EAMG). Rats with EAMG were treated with a protocol consisting of three components: (1) A single high dose of cyclophosphamide (200 mg/kg) was used to produce a rapid and sustained fall in the anti-AChR antibody levels by preferential destruction of antibody-producing B-lymphocytes. "Memory" lymphocytes were not eliminated by cyclophosphamide. (2) Irradiation (600 rads) was used to eliminate the "memory" cells. It eliminated the anamnestic response to a challenge with the antigen AChR. (3) Bone marrow transplantation was used to repopulate the hematopoietic system after the otherwise lethal dose of cyclophosphamide. We used bone marrow from syngeneic rats with active EAMG to simulate an autologous transplant. Rats with EAMG treated with this combined protocol showed a prompt and sustained fall in the anti-AChR antibody levels and had no anamnestic response to a challenge with AChR. Thus, an affected animal's own marrow could be stored and used later for repopulation after cyclophosphamide-irradiation treatment. This treatment eliminates the animal's ongoing immune responses and reconstitutes the immune system in its original state. The success of this approach suggests that, if their safety could be established, similar "curative" strategies might be developed for the treatment of patients with severe antibody-mediated autoimmune disorders, such as myasthenia gravis.  相似文献   
16.
Summary A total of 15 patients affected by idiopathic dystonia (7 with generalized and 8 with focal or segmental dystonia) were subjected to therapy with bromocriptine at low doses, pimozide and trihexyphenidyl. The symptoms were evaluated by giving a progressive score in relation to the intensity of the dystonic symptom to each of the body segments involved by the dystonia. Bromocriptine did not significantly modify the dystonia. Pimozide showed a slight nonsignificant improvement of the dystonic symptoms. Trihexyphenidyl was effective in the generalized dystonias, in agreement with previous reports in the literature. The variation in the pharmacological results could be due to the diversity of the dystonic syndromes, which comprise cases that are different in age at onset, site of dystonic symptoms, and evolution.
Zusammenfassung Fünfzehn von idiopathischer — und zwar 7 von generalisierter und 8 von fokaler und segmentarischer — Dystonie befallenen Patienten unterzogen sich verschiedenen pharmakologischen Behandlungen mit kleinen Mengen Bromocriptine, Pymozide und Triesifenidile. Die Symptome wurden durch eine fortlaufende Punktzahl bezeichnet, so daß deren Schätzung von der Intensität des Symptoms Dystonie in jedem einzelnen befallenen Körperteil abhing. Die Dystonien wurden durch Bromocriptine nicht bedeutend geändert.Pymozide führte zu einer geringeren, doch unbedeutenden, Besserung der dystonischen Symptome.Triesifenidile wirkte auf die generalisierten Dystonien, in Übereinstimmung mit einigen Literaturangaben.Die Veränderlichkeit der pharmakologischen Ergebnisse wurde auf die Verschiedenheit der dystonischen Syndrome zurückgeführt, unter denen man Fälle versammelt, die sich durch Anfangsalter, Sitz der dystonischen Symptome und Entwicklungsart voneinander unterscheiden.
  相似文献   
17.
In tissue engineering and regenerative medicine, studies that utilize 3D scaffolds for generating voluminous tissues are mostly confined in the realm of in vitro research and preclinical animal model testing. Bioreactors offer an excellent platform to grow and develop 3D tissues by providing conditions that mimic their native microenvironment. Aligning the bioreactor development process with a focus on patient care will aid in the faster translation of the bioreactor technology to clinics. In this review, we discuss the various factors involved in the design of clinically relevant bioreactors in relation to their respective applications. We explore the functional relevance of tissue grafts generated by bioreactors that have been designed to provide physiologically relevant mechanical cues on the growing tissue. The review discusses the recent trends in non‐invasive sensing of the bioreactor culture conditions. It provides an insight to the current technological advancements that enable in situ, non‐invasive, qualitative and quantitative evaluation of the tissue grafts grown in a bioreactor system. We summarize the emerging trends in commercial bioreactor design followed by a short discussion on the aspects that hamper the ‘push’ of bioreactor systems into the commercial market as well as ‘pull’ factors for stakeholders to embrace and adopt widespread utility of bioreactors in the clinical setting. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
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19.
Gastric mucosa‐associated lymphoid tissue lymphoma (or MALToma) is a relatively rare form of low‐grade B‐cell malignancy arising from the mucosal associated lymphoid tissue of the stomach. The majority of cases can be treated with Helicobacter pylori eradication with good prognosis. However, few reports have been published on the treatment of gastric MALToma with pulmonary metastasis. We report two such cases managed with systemic chemotherapy. At the time of writing, one of the cases was in static disease while the other had complete remission. In both patients, pulmonary metastases were detected upon staging thoracic computed tomography.  相似文献   
20.
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