体外培养脂肪组织来源干细胞与胶原/壳聚糖复合支架的亲和性

目的：制备适合脂肪组织来源的干细胞生长的支架,观察复合支架各组成的体积比率与细胞培养的亲和性. 方法：实验于2006-09/2007-01在大连理工大学干细胞与组织工程研发中心完成.①实验方法：将3.55 g/L Ⅰ型胶原和20 g/L壳聚糖分别以9∶1,7∶3,5∶5,3∶7,1∶9的体积比混合冻干,碳化二亚胺/N-羟基琥珀酰亚胺交联后再次冻干并进行分析.②实验评估：扫描电镜观察不同材料交联前后的微观结构;IPP软件分析计算支架的平均孔径;测量支架的吸水性和孔隙率;通过胶原酶检测支架的体外生物可降解性;扫描电镜和苏木精-伊红染色观察脂肪组织来源的干细胞在复合支架上的生长情况. 结果：①交联前后的微观结构：冻干后的各种支架材料呈白色,表面粗糙,材料内部呈海绵状多孔隙结构,其中以胶原/壳聚糖体积比为9∶1的复合支架最为疏松,1∶9的支架最致密.扫描电镜下支架的胶原含量越高,支架内的胶原丝越多,支架的孔与孔之间相互连通构成了通孔.交联前后支架的形态结构无明显改变.②支架的平均孔径∶交联后体积比为9∶1,7∶3和5∶5的复合支架孔径50～200 μm,可用于细胞的三维培养.③支架的吸水性和孔隙率∶体积比为5∶5的复合支架的吸水性和含水量最高,而7∶3次之;多孔支架在水中未发生明显的溶胀现象;支架的孔隙率均在90%以上.④支架的体外生物可降解性：未交联的支架随着胶原含量的减少,支架的降解速率增加.而交联后随着胶原含量的减少,降解速率减慢,交联后的复合支架降解速度较未交联慢.⑤脂肪组织来源的干细胞在复合支架上的生长情况：脂肪组织来源的干细胞在支架上培养5 d后扫描电镜观察细胞在7∶3的支架上爬行生长并融合成片,苏木精-伊红染色观察支架孔内及表面出现大量的细胞团,并融合成片状,而5∶5支架上黏附生长的细胞较少. 结论：结合支架的孔径、吸水性、孔隙率、体外生物可降解性和细胞与支架的生物相容性,可知体积比为7∶3的复合支架对脂肪组织来源的干细胞的亲和性较好,适于脂肪组织来源的干细胞的三维培养.     

PDLA/PLLA and PDLA/PCL nanofibers with a chitosan‐based hydrogel in composite scaffolds for tissue engineered cartilage

Osteoarthritis (OA) is the most prevalent musculoskeletal disease in humans, causing pain, loss of joint motility and function, and severely reducing the standard of living of patients. Cartilage tissue engineering attempts to repair the damaged tissue of individuals suffering from OA by providing mechanical support to the joint as new tissue regenerates. The aim of this study was to create composite three dimensional scaffolds comprised of electrospun poly(D,L‐lactide)/poly(L‐lactide) (PDLA/PLLA) or poly(D,L‐lactide)/polycaprolactone (PDLA/PCL) with salt leached pores and an embedded chitosan hydrogel to determine the potential of these scaffolds for cartilage tissue engineering. PDLA/PLLA‐hydrogel scaffolds displayed the largest compressive moduli followed by PDLA/PCL‐hydrogel scaffolds. Dynamic mechanical tests showed that the PDLA/PLLA scaffolds had no appreciable recovery while PDLA/PCL scaffolds did exhibit some recovery. Primary canine chondrocytes produced both collagen type II and proteoglycans (primary components of extracellular matrix in cartilage) while being cultured on scaffolds composed of electrospun PDLA/PCL. As a result, a composite electrospun embedded hydrogel scaffold shows promise for treating individuals suffering from OA. Copyright © 2012 John Wiley & Sons, Ltd.     

Transfacial approaches to the skull base: the early contributions of harvey cushing

In this report, we review Dr. Cushing's early surgical cases at the Johns Hopkins Hospital, revealing details of his early use of craniofacial approaches for malignant pathology of the skull base. Following Institutional Review Board approval, and through the courtesy of the Alan Mason Chesney Archives, we reviewed the Johns Hopkins Hospital surgical files from 1896 to 1912, which included three patients who underwent surgical treatment of lesions involving the skull base through craniofacial approaches: two adults and one child (range 3 to 43 years). The main outcome measures were length of stay and condition recorded at the time of discharge. The indications for surgery included osteochondroma of the sphenoid sinus, sarcoma of the maxillary sinus and middle fossa, and osteoma of the frontal sinus. The mean length of stay was 24.5 days (range 7 to 45 days). Cushing employed craniofacial approaches for malignant pathology nearly 40 years before such techniques became widely used. He practiced the fundamentals of skull base surgery, including preferential removal of bone to achieving adequate exposure for resection. In addition, Cushing clearly understood the importance of proximal vascular control in approaching lesions with complex vascular involvement.     

Structural violence, urban retail food markets, and low birth weight

This paper investigates urban retail food markets and health in Syracuse, New York. A structured observational analysis found that a majority of corner markets do not sell fresh produce or low fat dairy products, but conduct a lively business selling lottery tickets, cigarettes, and liquor. A comparison of census tracts with and without access to supermarkets that sell fresh produce and other healthy food found that pregnant women living in proximity to a supermarket had significantly fewer low birth weight births than other pregnant women regardless of income level.     

Acute kidney injury among medical and surgical in-patients in the Cape Coast Teaching Hospital,Cape Coast,Ghana: a prospective cross-sectional study

BackgroundAcute kidney injury (AKI) is a syndrome associated with high morbidity, mortality and high hospital costs. Despite its adverse clinical and economic effects, only a few studies have reported reliable estimates on the incidence of AKI in sub-Sahara Africa. We assessed the incidence and associated factors of AKI among medical and surgical patients admitted to a tertiary hospital in Ghana.MethodsA prospective cross-sectional study was conducted among one hundred and forty-five (145) consecutive patients admitted to the medical and the surgical wards at the Cape Coast Teaching Hospital (CCTH), Cape Coast, Ghana from April 2017 to April 2018. Socio-demographic and clinical information were collected using structured questionnaires. AKI was diagnosed and staged with the KDIGO guideline, using admission serum creatinine as baseline kidney function.ResultsThe mean age of the study participants was 46.6±17.7 years, whilst the male:female ratio was 68:77. The overall incidence of AKI among the participants was 15.9% (95% CI: 10.33 – 22.84%). Stage 1 AKI occurred in 56.5% of the participants, whilst stages 2 and 3 AKI respectively occurred among 4.1% and 2.8% of respondents. About 20% of the participants in the medical ward developed AKI (n= 15) whilst 12% of those in surgical ward developed AKI (n= 8). Among the participants admitted to the medical ward, 60.0%, 26.7% and 13.3% had stages 1, 2 and 3 AKI respectively. Whilst 50.0%, 25.0% and 25.0% respectively developed stages 1, 2 and 3 AKI in the surgical ward. Medical patients with AKI had hypertension (40%), followed by liver disease (33.3%); 37.5% of surgical inpatients had gastrointestinal (GI) disorders.ConclusionThe incidence of AKI is high among medical and surgical patients in-patients in the CCTH, Ghana, with hypertension and liver disease as major comorbidities.     

幽门螺杆菌感染患者血清可溶性幽门螺杆菌抗原及其 IgG,IgA型免疫复合物测定

目的　测定血清可溶性幽门螺杆菌抗原(S-Hp)和其特异性免疫复合物(Hp-IC)并评价它们对幽门螺杆菌感染诊断的意义.方法　采用双抗体夹心式酶免疫测定法.结果　66例Hp感染患者血清S-Hp阳性率90.91%,显著高于28例阴性对照组阳性率0%,P<0.001.S-Hp含量与Hp感染菌量呈成比,但43例Hp阳性患者治疗前后S-Hp 含量无显著改变（P>0.05）.血清 S-Hp抗原均以IgG和/或IgA型特异性免疫复合物形式存在,Hp-IC对Hp感染诊断特异性85.71%,敏感性77.23%. 结论　S-Hp和Hp-IC测定可用于临床Hp感染诊断,对阐明Hp致病机理有重要意义.