Membrane-Based PDMS Microbioreactor for Perfused 3D Primary Rat Hepatocyte Cultures

To improve primary adult rat hepatocyte cultures, two types of PDMS microbioreactors containing a membrane, used as a scaffold for the attachment of cells, were built: one with a commercially-available polyester membrane, the other with a PDMS membrane (5 x 5 microm hole sizes) made in our laboratory. In that way, the relative surface area between blood perfusion and hepatocytes seen in vivo was mimicked and as cells were bathed in both sides by the culture medium they expressed much higher functions. A new technique to build such PDMS membrane was created. With this technique we could build various PDMS membranes with down to 5 x 5 microm holes and with thickness even below 20 microm. During the fifteen days of perfusion in these microbioreactors, good cell attachment then cell reorganization was observed. Moreover compared to static cultures in tissue-culture-treated dishes and in cultures in inserts with the same polyester membranes, seven and two times increases in the albumin secretion by the cultured primary rat adult hepatocyte were demonstrated, respectively. Ammonium removal also increased 7 times in perfused cultures compared to static cultures. These new microbioreactors, which closely mimic the in vivo liver architecture, revealed themselves to be very promising tools towards future applications in drug screening or liver tissue engineering.     

用于生物人工肝的肝细胞组织化培养

肝细胞是生物人工肝支持系统的核心。组织化培养的肝细胞具有比常规培养肝细胞更好的功能。本文就近年来肝细胞组织化培养的发展作一综述 ,并归纳了肝细胞组织化研究的发展方向     

One Standardized Differentiation Procedure Robustly Generates Homogenous Hepatocyte Cultures Displaying Metabolic Diversity from a Large Panel of Human Pluripotent Stem Cells

Human hepatocytes display substantial functional inter-individual variation regarding drug metabolizing functions. In order to investigate if this diversity is mirrored in hepatocytes derived from different human pluripotent stem cell (hPSC) lines, we evaluated 25 hPSC lines originating from 24 different donors for hepatic differentiation and functionality. Homogenous hepatocyte cultures could be derived from all hPSC lines using one standardized differentiation procedure. To the best of our knowledge this is the first report of a standardized hepatic differentiation procedure that is generally applicable across a large panel of hPSC lines without any adaptations to individual lines. Importantly, with regard to functional aspects, such as Cytochrome P450 activities, we observed that hepatocytes derived from different hPSC lines displayed inter-individual variation characteristic for primary hepatocytes obtained from different donors, while these activities were highly reproducible between repeated experiments using the same line. Taken together, these data demonstrate the emerging possibility to compile panels of hPSC-derived hepatocytes of particular phenotypes/genotypes relevant for drug metabolism and toxicity studies. Moreover, these findings are of significance for applications within the regenerative medicine field, since our stringent differentiation procedure allows the derivation of homogenous hepatocyte cultures from multiple donors which is a prerequisite for the realization of future personalized stem cell based therapies.     

Histological typing of lung cancer. Application of the World Health Organization classification to 479 cases.

Four hundred and seventy nine primary lung cancers were typed according to the WHO histological classification. The character of the material and the methods of investigation are described. All patients had been subjected to mediastinoscopy and 313 patients had been operated upon. Nearly half of the tumours (48 per cent) was epidermoid carcinomas. Small cell anaplastic carcinoma occurred in 25 per cent and around two thirds of these were of oat cell type. Adenocarcinoma was found in 22 per cent and the acinar type predominated. Bronchiolo-alveolar carcinoma occurred in 1 per cent and large cell carcinoma in 3 per cent. Typing of biopsy specimens was made in 289 cases in which a positive biopsy had been obtained during the pretreatment period. The result of the biopsy typing was checked against that of the final one. In the total group the preoperative histological diagnosis tallied with the final one in 88 per cent. In patients who had been subjected to surgery the pretreatment diagnosis of the epidermoid carcinoma was correct in 86 per cent, that of small cell anaplastic carcinoma in 92 per cent and that of adenocarcinoma in 100 per cent. The consistency was also high in the category of patients not subjected to surgery. Despite their critical attitude towards the delimitation of epidermoid carcinoma in the WHO-classification the present authors find it to be a reliable guide to routine typing of lung cancer.     

Hepatocyte ultrastructural alterations in cocaine users

The ultrastructural examination of liver biopsies from five male cocaine users showed hepatocytes presenting diverse alterations in rough and smooth endoplasmic reticulum, mitochondria, nuclei and microvilli. Lipid deposition and an increase of autophagic vacuoles were also observed. This study demonstrates that the hepatocyte is an important target cell for cocaine toxic effects in some patients.     

Spermatogonia,Germline Cells,and Testicular Organization in the Characiform Prochilodus lineatus Studied Using Histological,Stereological, and Morphometric Approaches

Prochilodus lineatus is an important representative of the order Characiformes and a species that offers great advantages to fish farming. Therefore, detailed knowledge of its reproductive biology can be applied to various fields of production and biotechnology. In this study, we have identified testicular germ cells during spermatogenesis and have evaluated the volumetric proportion of the testes occupied by structures of the tubular and intertubular compartments. In addition, the individual volume of type A spermatogonia was measured and used to estimate the mean number of these cells per testis. Gonads of adult P. lineatus males were extracted and fixed. Light and transmission electron microscopy were applied to fragments of three testicular regions. Histological, stereological, and morphometric analyses were performed. The stereological data suggest that components of the tubular and intertubular compartments of the P. lineatus testes present a uniform distribution in all three regions and therefore reflect regions with similar distributions of cell types. In addition, P. lineatus testes showed ～0.6% of type A spermatogonia, as well as a predominance of cysts of primary spermatocytes and spermatids during the reproductive phase evaluated. The results from this study provide a better understanding of the morphology and structure of the testis and of the characterization of the type A spermatogonia in P. lineatus. The nuclear diameter of germ cells also decreases significantly during spermatogenesis. The data presented herein are the first of its kind for the order Characiformes and may be useful for future biotechnology studies on fish reproduction. Anat Rec, 300:589–599, 2017. © 2016 Wiley Periodicals, Inc.     

Hepatocyte cytokeratin 7 expression in chronic allograft rejection

We examined hepatocyte cytokeratin 7 (CK7) expression in chronic allograft rejection (CR), a ductopenic condition in which this has not been systematically evaluated, in 20 patients with the clinicopathologic diagnosis of CR and age-, sex-, and native-disease-matched control subjects. We also studied baseline biopsy specimens from both groups. Three pathologists independently reviewed H&E- and CK7-stained sections, counting interlobular bile ducts (BDs) and portal tracts (PTs), noting the morphologic pattern of injury and scoring hepatocyte CK7 expression (0, none; 1+, rare; 2+, multifocal, predominantly periportal; 3+, extension into the lobule; 4+, diffuse). Mean BD/PT ratios and CK7 scores were calculated. The mean BD/PT ratio (0.58) and CK7 score (1.01) for the "CR, diagnostic" group were significantly different from all other group means (P < .05); no other comparisons were significant (P > .05). A CK7 score of 1 or more was observed in 9 (56%) of 16 CR specimens and in 3 (7%) of 41 remaining specimens. Hepatocyte CK7 expression is frequently noted in CR, and it would appear to reflect ductopenia. CK7 staining may be a useful diagnostic adjunct in evaluation of transplant liver biopsy specimens.     

Histological findings in Morton's metatarsalgia

MORTON'S metatarsalgia is a distinctive clinical condition characterised by paroxysmal, lancinating pain in the forefoot in the region of the metatarso-phalangeal joints. The sensation is often described as that of (walking on a hot pebble). It is worse on walking, and typically eased by rest and by taking off the shoe. Manipulating the foot also sometimes eases the pain: it can cause sudden relief, the pain being replaced by a dull burning sensation.