胰岛素生长因子1在颅缝闭合中调节作用的实验研究

目的：研究胰岛素生长因子1对大鼠颅缝细胞的骨诱导作用和体外调节小鼠矢状缝闭合的作用。方法：获取新出生的SD大鼠的矢状缝细胞进行培养和出生8d的CD1小鼠矢状缝进行体外无血清器官培养基培养，加入胰岛素生长因子1（insulin lilce growth factor 1 IGF1），浓度分别为10ng/ml和40ng/ml，并设立不加IGF1者为对照组，应用RT－PCR检测颅缝细胞的成骨细胞表型碱性磷酸酶、骨钙素和骨桥蛋白mRNA表达，ELISA法检测培养液I型胶原的分泌，光镜观察小鼠矢状缝闭合的情况。结果：加入IGF1的矢状缝细胞的成骨细胞表型碱性磷酸酶、骨钙素和骨桥蛋白mRNA表达以及培养液I型胶原分泌量较对照组明显增高。有IGF1干预的矢状缝移植体培养8d时，颅缝内侧面骨板开始接近，培养20d时，颅缝小部分闭合，培养30d时颅缝大部分闭合，无IGF1干预的对照组培养30d，颅缝未发生闭合。结论：胰岛素生长因子1通过增强颅缝细胞的骨诱导促进颅缝的闭合。     

LI-RADS 4 or 5 categorization may not be clinically relevant for decision-making processes: A prospective cohort study

Introduction and objectivesThe liver imaging reporting data system (LI-RADS) for hepatocellular carcinoma (HCC) was proposed to standardize and enhance consensus of reporting. However, clinical utility of LI-RADS has not been evaluated in Latin America. We therefore sought to compare LI-RADS categories with histopathology findings in liver transplant (LT) explants in a regional center.Materials and methodsProspective cohort study conducted between 2012 and 2018 in a single center from Argentina including patients with HCC listed for LT. LI-RADS definitions were applied to magnetic resonance images (MRI) or computed tomography (CT) abdominal scans at time of listing and at final pre-LT reassessment and compared to explant pathology findings; specifically, major nodule (NOD1).ResultsOf 130 patients with HCC listed for LT (96.1% with cirrhosis and 35.6% with hepatitis C virus infection), 72 underwent LT. Overall, 65% had imaging HCC diagnosis based on MRI (n = 84), 26% with CT (n = 34) and 9% (n = 12) with both methods. Among LT patients with pre-transplant imaging at our institution (n = 42/72), 69% of the NOD1 were LR-5, 21% LR-4 and 10% LR-3. Definite HCC diagnosis was 50% in LR-3 NOD1 (CI 18–90); none presented microvascular invasion. In LR-4 NOD1, HCC was confirmed in 89% (CI 59–98), of which 11% showed microvascular invasion; whereas in LR-5 NOD1 77% (CI 64–87) had confirmed HCC, 17% with microvascular invasion.ConclusionsLI-RADS was useful to standardize reports; however, no significant differences were observed between LR-4 and LR-5 HCC probability when compared to explant pathology.     

Toxicity evaluation and nasal mucosal tissue deposition of dexamethasone-infused mucoadhesive in situ nasal gelling systems

To demonstrate safety of a developed intranasal dexamethasone-infused in situ gelling formulation, quantification of a validated clinical biomarker indicative of cytotoxic potential using a human sinonasal explant model was first confirmed. Systematic cytotoxicity studies using the lactate dehydrogenase (LDH) detection assay revealed no elevation from baseline, in LDH levels, with tissue integrity of explanted human nasal mucosa also maintained; this was further corroborated using tissue histopathological examination. Next, with safety confirmed ex vivo, freshly excised human nasal tissue was utilised to quantify dexamethasone release from the lead sol–gel systems; this being achieved through development and validation of a HPLC-UV analytical method, which reliably quantified controlled therapeutic release and deposition into mucosal tissue. Collectively, these findings indicate promise in the safety of each excipient within the concentrations employed in the functional sol–gel system, complemented by successful and reliable drug release and deposition into human nasal mucosal tissue. These findings pave the way for application of the dexamethasone-based sol–gel system to the extended delivery of corticosteroids to nasal mucosa in the management of localised inflammatory conditions of an acute and chronic nature, such as chronic rhinosinusitis, which can be expected to benefit from controlled and extended drug delivery characteristics imparted by appropriately engineered in situ gelling systems.     

激素配比对川芎外植体不定芽分化的影响

本文报道川芎Ligusticum chuanxiong Hort.外植体在不同激素配比的MS培养基中的分化效果。以培养基MS 6-BA 0.5mg/L NAA 0.5mg/L不定芽分化率最好,1/2 MS IAA 1.0 NAA 0.5(mg/L)的生根培养基可使不定芽形成小植株。     

耳蜗血管纹组织块的缘细胞培养

目的 :建立豚鼠耳蜗血管纹 (SV)组织块缘细胞 (MCs)的培养方法 ,为进一步研究药物耳毒性及其作用机制奠定基础。方法 :2 6只豚鼠按SV培养时间随机分成 4组 :2 4h组 (n =8) ;72h组 (n =8) ;>72h组 (n =8) ;对照组 (新鲜SV固定组 ,n =2 )。显微解剖数段连同螺旋韧带的SV组织块 ,置于 5 %CO2 / 95 %空气的二氧化碳恒温 (37℃ )培养箱中进行培养 ,分别进行形态学和组织学观察。结果 :培养 2 4hSV组织块保持良好活性 ,其组织学结构与新鲜固定的SV结构无明显差异 ;培养 72hSV组织块与新鲜固定的SV在组织学结构方面有显著性差异 ,不能观察到正常的SV结构 ,组织结构松散 ,缘细胞从组织块离心性生长出来 ;从SV组织块培养出的缘细胞能在培养皿内存活 13d。结论 :采用组织块培养技术 ,成功地建立了豚鼠耳蜗SV组织块的缘细胞培养方法 ;培养 2 4h的SV组织块光镜下保持了良好活性和正常组织学结构 ,可用来进一步研究药物耳毒性及其作用机制。     

Histomorphometry and cell kinetics of normal human bladder mucosa in vitro

Summary In this study, we have quantified the morphologic and kinetic parameters of explant cultured normal adult human urinary bladder mucosa. Quantitative parameters studied were urothelial height, cell density, labelling index and mitotic index. For these studies, urinary bladders from seven adults with no previous history of urologic disease were obtained at autopsy. Mucosal explants were maintained in rocking culture on Gelfoam rafts for up to 33 days using supplemented CMRL 1066 medium. Prior to sampling, cultures were treated with tritiated thymidine and colchicine to investigate tissue kinetics. Data was based on histologic autoradiograms. During culture, urothelial cells retained normal polarity. During the first week of culture, urothelial height increased and cell density decreased. DNA synthesis and mitotic activity occurred primarily among basal cells. DNA synthesis was first noted on day 2 of culture; mitotic activity began after 3 days of culture. Morphologically, human urothelium was well maintained; DNA synthesis and mitotic activity was variable but continued throughout culture.This work was supported by NIH Grant CA-28013     

Age-related changes in the kinetics of release of proteoglycans from normal rabbit cartilage explants

The release of proteoglycans from explant cultures of articular cartilage from immature and mature rabbits has been studied with the following results. At both ages the tissue proteoglycan was released in two phases: an initial extensive release (day 0 to 3) and a period of slow release (day 4 to 15). The percentage released in the initial phase was, however, significantly greater for mature (55%) than immature (38%) explants. At both ages the newly synthesized proteoglycans (in vivo labeled) were also released in two kinetic pools. Thus, graphical analysis of release data readily resolved the disappearance curves into two linear components with in vitro half-lives of 1 day and 22 days. Again, the percentage in the short half-life pool was much greater for mature (70%) than immature (40%) explants. At both ages the initial release was largely chondrocyte-mediated since freeze-thawing the tissue before culture markedly reduced proteoglycan release. At both ages the released proteoglycans were smaller than equivalent preparations of extracted proteoglycans and they were much less capable of forming aggregates with hyaluronate. The results show that there are age-dependent changes in rabbit articular cartilage that increase the proportion of proteoglycans, both total and newly synthesized, that are susceptible to rapid chondrocyte-mediated catabolism in explant cultures.     

不同外植体和激素组合对盾叶薯蓣组织培养的影响

目的探讨盾叶薯蓣组织培养的最佳外植体和激素组合。方法采用盾叶薯蓣茎段、叶为外植体 ,接种于不同激素组合的培养基上 ,观察比较培养情况。结果最佳外植体为腋芽萌发而来的无菌枝条切段 ,诱导愈伤组织的最佳培养基为MS +BA 1 .5mg·L-1+NAA 0 .5mg·L-1,不定芽分化的培养基为LS +BA1 .5mg·L-1,诱导生根的培养基为 1 2MS+NAA 1 .0mg·L-1。结论外植体的选择是盾叶薯蓣组织培养成功与否的关键所在     

Neurite-like outgrowth from CNS explants may not always be of neuronal origin

In living explants of the developing CNS ‘true’ neurites (neuronal processes) may appear virtually indistinguishable from the processes of radial and Bergmann glia. This inability to clearly distinguish the phenotype of responsive ‘neurites’ in the living state has profound implications for the interpretation of responses to ‘neurite-promoting’ substances. Labeling techniques, specific for intermediate filament proteins that are characteristic of neurons and neuroglia, should always be used to supplement morphologic observations on neurite-like outgrowth from living CNS explants.     

Differential epithelial outgrowth of plucked and microdissected human hair follicles in explant culture

In the present study we prepared explant cultures of plucked total hair follicles and of fragments microdissected from the following regions: B1 (bulb region), B2 (intermediate region), B3-1 (lower central outer root sheath, ORS), B3-2 (upper central ORS) and B4 (area of fracture). The growth capacities, the start of epithelial outgrowth, the stages of differentiation and apoptosis were studied immunohistochemically in early and late explant cultures using a battery of antibodies against cytokeratins, growth factor receptors and cell adhesion molecules and proliferation markers. Whole plucked hair follicles showed epithelial outgrowths exclusively in the upper central ORS (B3-2) starting early, mostly by day 3. In microdissected fragments, in contrast, outgrowths were more widespread, mostly in B3-2 and B3-1, and started early, but were also of late onset in some cases of B2 and B4. Epithelial outgrowths exhibited a basal layer of small cuboidal cells in a low stage of differentiation and one to two suprabasal layers of large prickle-like cells expressing late differentiation markers. The former expressed the receptor of nerve growth factor (NGF) heterogeneously whereas epidermal growth factor (EGF) receptor was not detectable. This is similar to ORS cells of this area in vivo. The proliferative activity of the outgrowths was always restricted to peripheral cells. Thus no essential differences in differentiation of outgrowing cells were detected. These results suggest that keratinocytes with the highest growth capacities in plucked human hair follicles are localized in the lower central ORS (corresponding to B3-2) and some with a lower capacity in the upper central ORS (corresponding to B3-1) as established after microdissection. This is in agreement with the bulge activation theory. NGF may also play a role in hair growth.