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S Linder

Publications and source records attributed to S Linder.

At least 145 records · Page 8Linked to original sources
PubMed1981

Reactivation of chicken erythrocyte nuclei in heterokaryons results in expression of adult chicken globin genes.

Activation of chicken globin gene transcription has been demonstrated in chicken erythrocyte--rat L6 myoblast heterokaryons. The globin mRNA is polyadenylylated and is translated into adult chicken alpha A-, alpha D-, and beta-globin polypeptides. No fetal globin mRNA or globin polypeptides were detected. Heterokaryons between chicken erythrocytes and mouse neuroblastoma cells or hamster BHK cells also synthesized adult chicken globins.

Animals↗
PubMed1977

Cells reconstituted from cell fragments of two different species multiply and form colonies.

Nuclei (minicells) prepared by cytochalasin-induced enucleation of rat myoblasts (L6) were fused with inactivated Sendai virus to preparations of cytoplasms from mouse fibroblasts (A9). Cell colonies arising from such fusion mixtures were examined 5 days after fusion. In the presence of virus a new type of colony was obtained. The cells in these colonies were derived from reconstituted cells capable of undergoing repeated cell divisions.

Cell Nucleus↗
PubMedDate not supplied

Two-dimensional gel analysis of protein expression in ovarian tumors shows a low degree of intratumoral heterogeneity.

The process of tumor progression leads to the emergence of multiple clones, and to the development of tumor heterogeneity. One approach to the study of the extent of such heterogeneity is to examine the expression of marker proteins in different tumor areas. Two-dimensional gel electrophoresis (2-DE) is a powerful tool for such studies, since the expression of a large number of polypeptide markers can be evaluated. In the present study, tumor cells were prepared from human ovarian tumors and analyzed by 2-DE and PDQUEST. As judged from the analysis of two different areas in each of nine ovarian tumors, the intratumoral variation in protein expression was low. In contrast, large differences were observed when the protein profiles of different tumors were compared. The differences in gene expression between pairs of malignant carcinomas were slightly larger than the differences observed between pairs of benign tumors. We conclude that 2-DE analysis of intratumoral heterogeneity in ovarian cancer tissue indicates a low degree of heterogeneity.

Cystadenoma, Mucinous↗
PubMedDate not supplied

Characterization of gene expression in clinical lung cancer materials by two-dimensional polyacrylamide gel electrophoresis.

Fourteen human lung tumors of various histopathological types were subjected to two-dimensional gel electrophoresis (2-DE). Samples were prepared for 2-DE using a nonenzymatic sample preparation (NESP) technique recently established in our laboratory. Variations in the expression of some polypeptides were observed between tumors of different histopathological types. To this end, high expression of beta-tubulin, heat shock proteins 73 and 90, lamin B, and proliferating cell nuclear antigen (PCNA) were observed in small cell lung carcinomas (SCLC). One polypeptide of unknown identity (35 kDa, pI 5.5) was significantly overexpressed in primary lung adenocarcinomas compared with SCLC, squamous cell lung carcinomas, metastatic lung adenocarcinomas from colon and rectum, and normal tissue. The amino acid composition of this polypeptide is presented. In summary, combining the NESP technique and 2-DE is an effective approach to define tumor-specific markers.

Adenocarcinoma↗
PubMedDate not supplied

Analysis of polypeptide expression in benign and malignant human breast lesions.

Results of two-dimensional electrophoresis (2-DE) analyses of human breast carcinoma are described. Tumor cells were extracted and purified from breast carcinomas with different proliferative indeces and degrees of genomic stability. Cells purified from fibroadenoma tissue served as controls for benign cells. The following results were observed: (i) Analysis of samples from different areas of the same tumor showed a high degree of similarity in the pattern of polypeptide expression. Similarly, analysis of two tumors and their metastases revealed similar 2-DE profiles. (ii) In contrast, large variations were observed between different lesions with comparable histological characteristics. Larger differences in polypeptide expression were observed between potentially highly malignant carcinomas compared to comparisons of less malignant lesions. These differences were in the same order of magnitude as those observed comparing a breast carcinoma to a lung carcinoma. (iii) The levels of all cytokeratin forms resolved (CK7, CK8, CK15, and CK18) were significantly lower in carcinomas compared to fibroadenomas. (iv) The levels of high molecular weight tropomyosins (1-3) were lower in carcinomas compared to fibroadenomas. The expression of tropomyosin-1 was found to be 1.7-fold higher in primary tumors with metastatic spread to axillar lymph nodes compared to primary tumors with no evidence of metastasis (p < 0.05). (v) The expression of proliferating cell nuclear antigen (PCNA) and some members of the stress protein family (pHSP60, HSP90, and calreticulin) were higher in carcinomas. We conclude that malignant progression of breast carcinomas results in large heterogeneity in polypeptide expression between different tumors, but that some common themes such as decreased expression of cytokeratin and tropomyosin polypeptides can be discerned.

Animals↗
PubMedDate not supplied

Endoscopic clearance of the pancreatic duct in chronic pancreatitis with severe pain.

In a phase I study endoscopic removal of pancreatic duct stones and protein plugs was attempted in five patients suffering from chronic pancreatitis with severe chronic pain. The pancreatic duct contents could be extracted after successful sphincterotomy in three patients. Clearance of the pancreatic duct was followed by complete or partial relief of pain. The follow-up period was 17-48 months. Endoscopic extraction is, however, not without complications; it is technically difficult, and many attempts may be required. The combination of endoscopic therapy and extracorporeal shock-wave lithotripsy may be a better alternative.

Aged↗