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GST Primary GST Primary Best Strategies for Health Care Quality Im... Best Strategies for Health Care Quality Improvement - Diabetes Quality Improvement Strategies for Antibio... Kathryn McDonald, Stanford-UCSF Evidence-b... Systematic review assessing the effect of ... Quality Improvement Strategies for Antibiotics Management Kathryn McDonald, Stanford-UCSF Evidence-based Practice Center, 117 Encina Commons, Stanford, CA 94305-6019, Kathy.mcdonald@stanford.edu Systematic review assessing the effect of quality improvement strategies on appropriate prescribing of antibiotics and appropriate choice of antibiotics. Adherence Adherence Assistive Devices Assistive Devices Childhood Burn Hanson MacMillan Childhood Burn Hanson MacMillan CLSA_9 CLSA_9 Cyberabuse Cyberabuse Cognitive Behavioural Therapy for Violent ... This review included randomized trials abo... Cognitive Behavioural Therapy for Violent Men who Batter Their Partners This review included randomized trials about the effects of cognitive behavioral therapy on domestic violence. The intervention included programs based on the Duluth Model. The violence had to be committed by a male toward his female partner. The violence also had to be physical. The primary outcomes were new arrests and convictions, and new reports of violence. CABG vs PCI CABG vs PCI Quality Improvement Strategies for Prevent... Quality Improvement Strategies for Preventing Nosocomial Infections (Created 17-Feb-06) Quality Improvement Strategies for Asthma ... Quality Improvement Strategies for Asthma Control Erectile Dysfunction (Created 30-Jan-06) Erectile Dysfunction (Created 30-Jan-06) Inequality - Smoking Cessation to Reduce S... This review was the first part of a projec... Inequality - Smoking Cessation to Reduce Socio-Economic Differences This review was the first part of a project about inequality. It included randomized trials about the effect of smoking cessation interventions on reducing socio-economic differences. The studies had to report data either on persons with low socio-economic groups status or, preferably, on both low and high socio-economic groups. Diet and Physical Activity to Reduce Socio... This review was the second part in a proje... Diet and Physical Activity to Reduce Socio-Economic Differences This review was the second part in a project about inequality. It included randomized trials about the effect of interventions on reducing socio-economic differences in diet and physical activity. The studies had to report data either on persons with low socio-economic groups status or, preferably, on both low and high socio-economic groups. Workfare The data in SRS are not identical to the d... Workfare The data in SRS are not identical to the data in the published report. We used SRS only for an updated search. The review included randomized trials about the effect of welfare-to-work programs. Participants were welfare recipients. There were basically two types of programs. The educational type tried to build knowledge and skills in order to help the welfare recipients acquire jobs that could support them economically. The "work first" approach was more aimed at getting the participants quickly into a job. Exercise interventions for the management ... The objective of this systematic review wa... Exercise interventions for the management of frailty The objective of this systematic review was to examine the effectiveness of current exercise interventions on the management of frailty. A comprehensive search of Medline, Embase, Psycinfo, Cinahl, Scopus, Ageline, Eric, and SportDiscus databases was conducted and produced 1808 citations. So far we have completed 2 levels of “title and abstract” screening and we ended up with 262 articles. We have just started the full text screening. Eligibility criteria included original studies whose participants were identified as frail or prefrail with specific criteria and in which structured physical activity was included as at least one component of the intervention. Create a free account, build a dictionary with saved terms to re-use later! Public Domestic Violence - Using Cognitive Behavior Therapy Smoking Cessation to Reduce Socio-Economic Differences Diet and Physical Activity to Reduce Socio-Economic Differences Workfare Exercise Interventions for the Management of Frailty Search     Simple Advanced Refine (4 coded questions)  Any of these:   Exact Phrase: All of these: None of these: Author: Periodical: Projects: No restrictions   Libraries: Public   Select SRS Projects Show Saved Terms Select Library Show articles that do not have abstracts  Ages All Infant: birth-23 months All Child: 0-18 years All Adult: 19+ years Newborn: birth-1 month Infant: 1-23 months Preschool Child: 2-5 years Child: 6-12 years Adolescent: 13-18 years Adult: 19-44 years Middle Aged: 45-64 years Middle Aged + Aged: 45+ years Aged: 65+ years 80 and over: 80+ years Undetermined Humans or Animals Humans Animals Type of Article Clinical Trial Editorial Letter Meta-Analysis Practice Guideline Randomized Controlled Trial Review Addresses Bibliography Biography Case Reports Classical Article Clinical Conference Clinical Trial, Phase I Clinical Trial, Phase II Clinical Trial, Phase III Clinical Trial, Phase IV Comment Comparative Study Consensus Development Conference Consensus Development Conference, NIH Controlled Clinical Trial Corrected and Republished Article Dictionary Directory Duplicate Publication English Abstract Evaluation Studies Festschrift Government Publications Guideline Historical Article Interview In Vitro Journal Article Lectures Legal Cases Legislation Multicenter Study News Newspaper Article Overall Patient Education Handout Periodical Index Published Erratum Retracted Publication Research Support, N.I.H., Extramural Research Support, N.I.H., Intramural Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. 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Retraction of Publication Scientific Integrity Review Support of Research Technical Report Twin Study Validation Studies Not a Primary Study or Review Unknown Primary Study Case Series Case Control Cohort Study Observational Study Qualitative Research CBA or ITS Registry Double Blind Controlled before after study Quasi-randomized trial Simple before after study Cluster-RCT Non-Randomized Study Report Book Book chapter Dissertation Conference procedings Secondary Research Not RCT Language English French German Italian Japanese Russian Spanish Afrikaans Albanian Unknown Arabic Armenian Azerbaijani Bosnian Bulgarian Catalan Chinese Croatian Czech Danish Dutch Esperanto Estonian Finnish Georgian Greek, Modern Hebrew Hindi Hungarian Icelandic Indonesian Kinyarwanda Korean Latin Latvian Lithuanian Macedonian Malay Malayalam Maori Multiple Languages Norwegian Persian Polish Portuguese Pushto Romanian Sanskrit Scottish gaelic Serbian Slovak Slovenian Swedish Thai Turkish Ukrainian Vietnamese Not English Not French Results(1-25 of 25,000) Sort By: Publication Date Relevance Took: 1.282 seconds to search 17,750,454  Action: Copy Results to new Clipboard Build Search Link Page 1 of 1000 1 2 3 4 > Last >> (25000 articles found) - Somatic symptoms for diagnosing major depression in cancer patients. [References] 5-20-2003 Akechi, Tatsuo, Nakano, Tomohito, Akizuki, Nobuya, Okamura, Masako, Sakuma, Keiko, Nakanishi, Tatsuro, Yoshikawa, Eisho, and Uchitomi, Yosuke - Diagnosing depression in cancer patients has been challenging because its diagnostic criteria include somatic symptoms frequently attributed to the cancer itself or its treatment. However, few studies have explored how to appropriately deal with individual somatic symptoms. The authors used data ... ( view more )from 220 cancer patients with major depression (aged 17-85 yrs) to examine the intercorrelations among the DSM-IV somatic and nonsomatic symptom criteria as well as whether the presence of an individual somatic symptom could discriminate the severity of major depression. Appetite changes and a diminished ability to think were positively associated with anhedonia. Sleep disturbance and fatigue were not significantly associated with nonsomatic symptoms. These associations were consistent after adjusting for physical functioning and pain. Only patients with appetite changes showed a higher severity of depression. These results suggest that individual somatic symptoms differ in nature and that appetite-related symptoms and a diminished ability to think may be useful for diagnosing depression in cancer patients, whereas sleep disturbances and fatigue may not be as useful. (PsycINFO Database Record (c) 2005 APA, all rights reserved) ( view less ) View Full Abstract View Article Details   Related Articles - The natural history of somatization in primary care 5-19-1999 Gureje, Oye and Simon, Gregory E. - Provides data on the incidence and persistence of current somatization syndrome in a large cross-national sample drawn from 15 sites in 14 countries. After screening with the General Health Questionnaire, a stratified sample of 5,438 primary care patients (aged 18-65 yrs) was interviewed with the... ( view more ) Composite International Diagnostic Interview and evaluated for physical health status, self-rated overall health and for occupational disability. 3,204 of the Ss completed follow-up interviews 12 mo later. Results show that an abridged form of somatization defined as 4 current symptoms in males and 6 in females was persistent in 45.9% of the Ss. Persistence of syndrome was related to age and to subjective indices of psychological distress at baseline. Persistence was unrelated to depression. The 12-mo incidence of the abridged somatization syndrome was 7.1 %. Ss with depression at baseline and those with poor view of their health were more likely to develop new episodes of somatization 12-mo later. (PsycINFO Database Record (c) 2005 APA, all rights reserved) ( view less ) View Full Abstract View Article Details   Related Articles The natural history of somatization in primary care 1999 Gureje, Oye and Simon, Gregory E. Provides data on the incidence and persistence of current somatization syndrome in a large cross-national sample drawn from 15 sites in 14 countries. After screening with the General Health Questionnaire, a stratified sample of 5,438 primary care patients (aged 18-65 yrs) was interviewed with the C... ( view more )omposite International Diagnostic Interview and evaluated for physical health status, self-rated overall health and for occupational disability. 3,204 of the Ss completed follow-up interviews 12 mo later. Results show that an abridged form of somatization defined as 4 current symptoms in males and 6 in females was persistent in 45.9% of the Ss. Persistence of syndrome was related to age and to subjective indices of psychological distress at baseline. Persistence was unrelated to depression. The 12-mo incidence of the abridged somatization syndrome was 7.1 %. Ss with depression at baseline and those with poor view of their health were more likely to develop new episodes of somatization 12-mo later. (PsycINFO Database Record (c) 2005 APA, all rights reserved) ( view less ) View Full Abstract View Article Details   Related Articles Somatic mutation screening: Identification of individuals harboring K- ras mutations with the use of plasma DNA 2000 Kopreski, M. S., Benko, F. A., Borys, D. J., Khan, A., McGarrity, T. J., and Gocke, C. D. Background: Many cancers are attributed to somatic mutation of DNA. We investigated whether it is feasible to detect cancer-associated somatic mutations in patients with neoplasms by using plasma DNA. Methods: Plasma samples were prospectively collected from 240 patients undergoing colonoscopy. Col... ( view more )orectal biopsies were performed as clinically indicated in 135 patients, and risk factor information was available from 232 patients. DNA was extracted from plasma and colorectal tissue and was amplified by use of a polymerase chain reaction method that enriches for mutations in codon 12 of the K-ras oncogene. Molecular, histologic, and clinical data were compared by use of two-sided Fisher's exact test. Results: Mutations in the K-ras gene detected in the plasma of 64 (28%) of 232 patients were statistically significantly associated with colorectal cancer risk factors (P = .0002). Of those patients having tissue available for comparison (n = 135), mutations in the K-ras gene were found in the tissues of 35 patients, and 29 (83%) of these 35 showed mutations in plasma samples. In contrast, the plasma assay was negative in 93 of the 100 patients whose tissue K-ras was wild-type. Among patients without biopsies (n = 105), 28 had mutated K-ras in their plasma DNA, despite the absence of remarkable colonoscopy findings; 24 of these 28 patients had risk factors for colorectal cancer. Overall, 25 (39%) of 64 patients showing mutations in plasma DNA had colorectal neoplasms with K-ras mutations compared with five (3%) of 176 patients without K-ras mutations in plasma DNA. Conclusion: Plasma DNA assays for the detection of mutations in K-ras codon 12 may provide a feasible method to screen populations for somatic mutations frequently found in neoplasms. The clinical utility of using this test in screening populations requires further study ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Psychological well-being in women with Turner syndrome: Somatic and social correlates. [References] 2004 Boman, U. Wide, Bryman, I., and Moller, A. Our aim was to examine possible somatic and social correlates to psychological well-being in adult women with Turner Syndrome (TS), including hormone replacement treatment Sixty-three women with a diagnosis of TS (mean age, 31.5 years) participated in a cross-sectional study, using interview data, ... ( view more )ratings on the Psychological General Well-being (PGWB) Index, and data from medical examinations and medical records. Statistical analysis was performed by bivariate and multivariate analyses. Lack of sex hormones during adult life and the presence of hearing impairment were related to lower psychological well-being, as were higher age at diagnosis, higher age at menarche or induced bleeding, higher chronological age and retrospectively reported difficulties with school subjects. Age at diagnosis and difficulties with school subjects explained 25% of the variation in psychological well-being. This study has identified some correlates to psychological well-being in women with TS, which are important when considering the clinical management of adult women with TS. (PsycINFO Database Record (c) 2005 APA, all rights reserved) (journal abstract) ( view less ) View Full Abstract View Article Details   Related Articles Anxiety and depressive disorders in an adult insulin-dependent diabetic mellitus (IDDM) population: Relationships with glycaemic control and somatic complications 1998 Friedman, S., Vila, G., Timsit, J., Boitard, C., and Mouren-Simeoni, M. C. The frequency of anxiety and depressive disorders was examined in 69 insulin-independent diabetic mellitus (IDDM) outpatients and in 2 control groups. Based on self-report measures, these disorders were similar in IDDM sample and in the control groups. In diabetic outpatients, according to the Diag... ( view more )nostic and Statistical Manual of Mental Disorders-III-Revised (DSM-III-R) criteria, there was a high lifetime prevalence of not otherwise specified anxiety and depressive disorders (44% and 41.5%), of simple phobia (26.8%), social phobia (24.6%), and agoraphobia--with and without panic disorder (14.6%). Current social phobia, dysthymia and not otherwise specified depressive disorders were associated with impaired glycaemic control. Glycosylated haemoglobin was associated with compliance but psychiatric disorders were not, except for social phobia which was significantly associated with more frequent consultations and a bad compliance for dietary regimen (more snacking). Somatic complications were not associated with anxious and depressive disorders (current or lifetime) or compliance and were best explained by the duration of the illness and impaired glycaemic control. (PsycINFO Database Record (c) 2005 APA, all rights reserved) ( view less ) View Full Abstract View Article Details   Related Articles Somatic healthcare utilization among adults with serious mental illness who are receiving community psychiatric services 2003 Dickerson, F. B., McNary, S. W., Brown, C. H., Kreyenbuhl, J., Goldberg, R. W., and Dixon, L. B. BACKGROUND/OBJECTIVE: Somatic health care utilization was studied among individuals with serious mental illness who were receiving community-based psychiatric services. RESEARCH DESIGN: Cross-sectional study. SUBJECTS: A total of 200 outpatients, 100 with schizophrenia and 100 with affective disord... ( view more )er, were recruited from randomly selected samples receiving care at two psychiatric centers. MEASURES: Patients were interviewed using questions from national health surveys. Multiple logistic regression analyses were used to compare responses from each sample to those of matched subsets of individuals from the general population. RESULTS: The psychiatric samples were more likely to report receiving some medical care services in the past year than were individuals in the general population including having visited a general medical doctor (Odds ratio, schizophrenia sample = 2.04; Odds ratio, affective disorder sample = 2.37) and having a complete physical examination (Odds ratio, schizophrenia sample = 2.69; Odds ratio, affective disorder sample = 1.74). However, our samples were less likely to receive routine dental care (Odds ratio, schizophrenia sample = 0.46; Odds ratio, affective disorder sample = 0.60). Perceived barriers to receiving medical care were reported significantly more often by the patient groups than the comparison groups (Odds ratios > 3). CONCLUSIONS: General health services are widely utilized by individuals with serious mental illness who are in outpatient psychiatric care. Dental services remain underutilized, however, and there is a high rate of perceived barriers to receiving medical care in this population ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Attachment theory: A model for health care utilization and somatization 2002 Ciechanowski, P. S., Walker, E. A., Katon, W. J., and Russo, J. E. Objective: Attachment theory proposes that cognitive schemas based on earlier repeated experiences with caregivers influence how individuals perceive and act within interpersonal relationships. We hypothesized that medical patients with two types of insecure attachment - preoccupied and fearful att... ( view more )achment - would have higher physical symptom reporting compared with those with other attachment styles, but that preoccupied attachment would be associated with higher and fearful attachment with lower primary care utilization and costs. Methods: In a large sample of adult female primary care health maintenance organization patients (N = 701), we used analysis of covariance and Poisson regressions to determine whether attachment style was significantly associated with 1) symptom reporting based on questions from the somatization section of the Diagnostic Interview Schedule and 2) contemporaneous automated utilization and cost data. Results: Attachment style was significantly associated with symptom reporting (p = .02), with patients with preoccupied (p = .03) and fearful (p = .003) attachment having a significantly greater number of physical symptoms compared with secure patients. There were no significant differences in medical comorbidity between attachment groups. Attachment was also significantly associated with primary care visits and costs. Patients with preoccupied attachment had the highest primary care costs and utilization, whereas patients with fearful attachment had the lowest. Conclusions: These results suggest that attachment style is an important factor in assessing symptom perception and health care utilization. Despite being on opposite ends of the utilization spectrum, patients with preoccupied and fearful attachment have the highest symptom reporting. These data challenge the observation that increased symptom reporting is uniformly associated with increased utilization in medical patients ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Human RNA transcripts in man-mouse somatic cell hybrids. II. Thermal denaturation studies and Cot analysis. Jul 1975 R A DiCioccio,M Siniscalco The present report confirms an earlier finding that human RNA transcripts from a man-mouse somatic cell hybrid that has regularly retained only the human X chromosome can be identified by molecular hybridization on nitrocellulose filters. From thermal denaturation studies it is concluded that molec... ( view more )ular hybrids between hybrid cell and human nucleic acids have higher Tm's, and thus greater specificity, than those between mouse and human nucleic acids. Additional data, utilizing the kinetics of molecular hybridization in solution (Cot analysis), demonstrate the presence of "few gene copy" DNA sequences in the above-mentioned hybrid cells that are complementary to human (HeLa) HnRNA. Also shown is a fraction of hybrid cell HnRNA that is complementary to "few gene copy" DNA sequences of human DNA. Thus, the experiments reported may represent a specific assay for identifying reiterated and "few gene copy" DNA sequences of the human X chromosome and their complementary RNA. Theoretically this experimental approach may be extended to any chromosome. Some of the short-term and long-term perspectives of these types of studies are discussed. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Analysis of tumor suppressor gene on human chromosome 9 in mouse x human somatic cell hybrids. Sep 1994 B W Porterfield,O I Olopade,J D Rowley,M O Diaz Deletions of the short arm of human chromosome 9 (9p) are common in human leukemia and solid tumors. The minimum region of overlap of these deletions, located between the interferon genes and the methylthioadenosine phosphorylase gene, is partially syntenic with a region of mouse chromosome 4 that ... ( view more )has tumor suppressor activity. Somatic cell hybrids between tumorigenic, MTAP-deficient, mouse L cells, and MTAP-competent human cells containing either a normal copy of 9p or a 9p with a deletion involving band 9p21 were selected in culture conditions that require MTAP activity for continued growth. Somatic cell hybrids that contained a normal copy of 9p rarely formed tumors in nude mice. Cells from the rare tumors that grew had lost the normal 9p. Hybrid cells that contained a 9p with deletions formed tumors more frequently, and cells from these tumors retained the 9p deletion chromosome. These results provide evidence that a tumor suppressor gene (or genes) is located on human chromosome 9 within the region of deletion. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Mapping human chromosomes in somatic cell hybrids using a low-copy-number repetitive sequence. Jul 1986 D J Shaw,J D Brook,C S Brown,N S Thomas We have isolated a human-specific repetitive sequence with a copy number of several hundred (p11L26). Using Southern blots of EcoR1-digested DNA from somatic cell hybrids containing one or a few human chromosomes, band patterns specific for those chromosomes can be generated by hybridization with p... ( view more )11L26. Genomic copies of the sequence have also been mapped to subchromosomal regions using translocations. The probe offers a useful addition to the standard techniques for mapping human chromosomes in hybrid cell lines. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Cell-surface antigens determined by human chromosomes 1 and 12: comparative serological and somatic cell genetic analysis of eight antigenic systems. Jan 1986 W J Rettig,N C Dracopoli,B A Spengler,J H Kersey,J L Biedler,L J Old We have previously assigned several genes controlling expression of cell-surface antigens to human chromosomes 1 and 12. In the present study, we characterize three additional cell-surface antigens determined by these chromosomes. Two monoclonal antibodies, AbSR75 and AbMG6, define antigens express... ( view more )ed on a wide range of cultured human cells. In contrast, AbK66 defines an antigen with a more restricted distribution which is expressed on normal and malignant human epithelial cells but not on neuroectoderm-derived cells or hematopoietic cells. Normal adult fibroblasts are K66-, whereas fetal fibroblasts are K66+. Serological analysis of rodent-human hybrid cells permitted the assignment of MSK31, controlling SR75, and MSK32, controlling K66, to chromosome 1, whereas MSK27, controlling MG6, maps to chromosome 12. Analysis of hybrids containing only deleted copies of chromosome 1 or chromosome 12 established regional assignments for MSK31, MSK32, and MSK27 and also for the previously defined genes MSK1, MSK4, and MSK7. The MSK1 gene, coding for a 140,000 mol wt cell surface glycoprotein, was found to map to the same band (1p22) as the NRAS protooncogene and the gene encoding the beta-subunit of nerve growth factor (NGFB). ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Characterization of somatic cell hybrids exhibiting extinction of AFP, albumin and an AFP-HPRT transgene. Mar 1996 M J Keherly,C C Hsieh,J L McCombs,L S Merryman,J Papaconstantinou We utilized an AFP-HPRT transgene, i.e. the HPRT coding sequences under the regulation of AFP enhancer and promoter sequences, to localize the AFP extinguisher locus in intertypic somatic cell hybrids (hepatoma X fibroblast). This hybrid gene construct, which directly links AFP regulation to a reve... ( view more )rsibly selective gene, enabled the selection of stably transfected cells which express AFP, as well as cells showing extinction of AFP. Mouse hepatoma cells stably transfected with and expressing the transgene were fused to human fibroblasts, and the resulting somatic cell hybrids were characterized using Southern, Northern and karyotypic analyses. That several hybrids exhibited the proper extinction of AFP, AFP-HPRT and albumin suggests coregulation of these genes by an extinguisher. Segregant lines derived from these hybrids were selected for the loss of extinguisher activity and for reexpression of the transgene. Karyotypic analysis of hybrid and segregant lines, exhibiting proper AFP, albumin and AFP-HPRT phenotypes, revealed that the presence of human chromosome 7 was most closely associated with the AFP-extinguished state. The hybrids generated in these studies now make it possible to isolate the sequences responsible for AFP and albumin extinction. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Molecular analysis and breakpoint definition of a set of human chromosome 21 somatic cell hybrids. Nov 1995 S L Graw,K Gardiner,K Hall-Johnson,I Hart,A Joetham,K Walton,D Donaldson,D Patterson Rodent-human somatic cell hybrids containing single human chromosomes or chromosome fragments are extremely valuable in physical mapping, marker analysis, and disease mapping. Chromosome 21 has been extensively studied in this fashion, and a single set of hybrids has been utilized in mapping the ma... ( view more )jority of chromosome 21 markers. The utility of a set of hybrids depends upon the definition of the human chromosome content. Recently, Chumakov and coworkers (1) utilized 198 chromosome 21 markers in the preliminary analysis of YACs spanning chromosome 21q. We have used these same markers to evaluate the STS content of a set of 27 chromosome 21 somatic cell hybrids, resulting in the description of the breakpoints at the molecular level, as well as the definition of 35 "bins. " The detailed molecular definition of chromosome 21 content of the hybrids, in combination with the further analysis of chromosome 21 YACs (2), has resulted in the most detailed picture of chromosome 21 to date. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Paroxysmal nocturnal hemoglobinuria: correction of abnormal phenotype by somatic cell hybridization. Mar 1993 P Hillmen,M Bessler,J Bungey,L Luzzatto Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired blood disorder thought to result from a somatic mutation in a hemopoietic stem cell. PNH may evolve to aplastic anemia or to acute leukemia. PNH cells are deficient in proteins attached to the cell membrane via a glycosylphosphatidylinositol ... ( view more )structure, called the GPI anchor, and the primary lesion in PNH is thought to be a defect in the biosynthesis of the GPI anchor. We have recently established permanent lymphoblastoid cell lines that have the PNH phenotype and we report now the isolation of human-human somatic cell hybrid clones obtained by fusing them with normal lymphoblastoid cells. In all of 21 hybrid clones, obtained from five different patients, the expression of three different GPI-linked proteins on the hybrid cells was normal. These findings indicate that the PNH mutant gene is recessive with respect to the normal allele and that a recessive mutation can cause a clonal preneoplastic disorder. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles An evaluation of the inactive mouse X chromosome in somatic cell hybrids. Jan 1993 E C Salido,M B Passage,P H Yen,L J Shapiro,T K Mohandas The expression of mouse Zfx, Rps4, Ube1x, and Xist was evaluated in hamster-mouse somatic cell hybrids containing either an active or an inactive mouse X chromosome using polymerase chain reaction of reverse transcribed RNA (RT-PCR). The results showed that Zfx, Rps4, and Ube1x are expressed exclus... ( view more )ively from the active mouse X, while Xist is expressed exclusively from the inactive X. These findings confirm the pattern of X inactivation for these mouse genes reported previously based on expression in somatic tissues of F1 females from interspecific crosses. These results demonstrate the existence of differences between human and mouse X inactivation, as the corresponding human genes, ZFX, RPS4X, and UBE1 escape X inactivation. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Chromosomal assignments of mouse connexin genes, coding for gap junctional proteins, by somatic cell hybridization. Jul 1992 H J Schwarz,Y S Chang,H Hennemann,E Dahl,P A Lalley,K Willecke The connexin genes Cx31 and Cx45 coding for proteins of gap junctional subunits have been assigned to mouse chromosomes 4 and 11 by Southern blot hybridization of specific gene probes to DNA from mouse x Chinese hamster somatic cell hybrids. In addition, our results confirm the recent assignment of... ( view more ) mouse connexin genes Cx26, Cx32, Cx37, Cx40, Cx43, and Cx46 to mouse chromosomes 14, X, 4, 3, 10, and 14, respectively, by analysis of interspecific backcrosses and by somatic cell hybridization. Our assignment of the Cx31 gene to mouse chromosome 4 locates the fourth connexin gene on this mouse chromosome to which the genes for Cx31.1, Cx37, and Cx30.3 have previously been assigned. Interestingly three of them (coding for Cx31, Cx31.1, and Cx30.3) are preferentially expressed in skin. Possibly some of the connexin genes clustered on mouse chromosome 4 may be regulated coordinately. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Detection of multiple tumor suppressor genes for Syrian hamster fibrosarcomas by somatic cell hybridization. Mar 1992 R E Whitehead,O Sugawara,R R Maronpot,B C Gladen,J C Barrett Identification of tumor suppressor gene loci in rodent cell culture systems has relied upon the use of somatic cell hybridization studies. Although normal rodent fibroblasts are capable of suppressing the tumorigenicity of a variety of tumor cells, the lack of complementation in tumor cell x tumor ... ( view more )cell hybrids has left the possibility that a single tumor suppressor gene may be responsible for tumor suppression in a particular rodent cell culture system. Using this same approach, we found no evidence for complementation resulting in suppression of the transformed phenotype when three viral oncogene-transformed Syrian hamster embryo (SHE) cell lines and one spontaneously transformed baby hamster kidney (BHK) cell line were fused to benzo[a]pyrene-transformed SHE cells (BP6T-M3). However, v-src oncogene-transformed cell line (srcT) x BP6T-M3 hybrids did demonstrate limited suppression of the transformed phenotype, suggesting at least two complementing tumor suppressor genes in this system. We were able to confirm and extend this finding using another experimental approach with preneoplastic hamster cell lines that are immortal in culture but nontumorigenic in nude mice. We propose that fusion of these preneoplastic cells to various tumor cells may reveal tumor suppressor genes not evident in the tumor cell x tumor cell complementation studies. Subclones of two nontumorigenic, immortal hamster cell lines, 10W and DES4, displayed differing abilities to suppress BP6T-M3 cells in somatic cell hybrids, as quantitated by the ability of the hybrid cells to form colonies in soft agar. With a panel of preneoplastic hamster cell x BP6T-M3 hybrids, a distinct pattern of suppression or expression of the transformed phenotype was observed. Marked differences in this pattern were seen when the same 10W and DES4 subclones were fused to other hamster fibrosarcoma cell lines, indicating different tumor suppressing activities of multiple tumor suppressor genes. Analysis of this data suggests that as few as three or as many as six different tumor suppressor genes may be active in the Syrian hamster embryo cell culture system. Thus, this system may provide a useful model for identifying and studying the effects and regulation of a number of different tumor suppressor genes for fibrosarcomas. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Gene expression and metastasis of somatic cell hybrids between murine fibroblast cell lines of different malignant potential. Jul 1991 A B Tuck,S M Wilson,F R Sergovich,A F Chambers We have used somatic cell hybrids to study the relationship between ras sensitivity, metastasis, and the expression of ras-responsive or "metastasis-associated" genes. We have previously shown that NIH 3T3 cells are nontumorigenic, but are made metastatic by transfection and expression of activated... ( view more ) ras (i.e., they are ras-sensitive). LTA cells, however, are initially tumorigenic, but nonmetastatic, and are not altered in malignancy by ras (i.e., they are ras-resistant). We also have shown that patterns of expression of ras-responsive and "metastasis-associated" genes differ markedly between these two cell types. In the present work, we have constructed three sets of somatic cell hybrids: NIH 3T3 X LTA cells (designated NL), NIH 3T3 X ras-transfected LTA cells (designated NLR), and LTA X ras-transfected NIH 3T3 cells (designated LNR). In all three sets of cell hybrids, pooled clones were found to be highly metastatic in the chick embryo assay, suggesting complementation had occurred. Those cell hybrids that contained ras (NLR and LNR hybrids) were significantly more metastatic than those that did not (NL hybrids). Selected clones of low and high metastatic ability from both NL and LNR fusions were examined for tumorigenicity and "experimental" metastatic ability in nude mice, as well as for expression of several genes thought to be involved in ras-induced progression and malignancy. Patterns of expression of these genes showed a relationship to level of malignancy of the hybrids and demonstrated a responsiveness to the expression of activated ras. These results suggest that the complementation of phenotype observed in the hybrids may arise through a gene regulatory factor(s) supplied by the NIH 3T3- to the LTA-derived parent. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles DNA methylation of two X chromosome genes in female somatic and embryonal carcinoma cells. Jan 1991 M H Bartlett,C N Adra,J Park,V M Chapman,M W McBurney The extent of methylation of DNA sequences upstream and within the two X-linked genes, Pgk-1 and Hprt, was analyzed in male and female somatic cells and in female embryonal carcinoma cells carrying either two active X chromosomes (Xa) or one active and one inactive X chromosome (Xi). Sites upstream... ( view more ) and within the first intron of both Pgk-1 and Hprt were heavily methylated on the Xi in somatic cells and in embryonal carcinoma cells with an Xi. Reactivation of this Xi was accompanied by extensive demethylation of these sites. In female embryonal carcinoma cells with two active X chromosomes, one X inactivates during differentiation in culture; however, methylation did not occur during differentiation, consistent with the idea that DNA methylation does not play a role in the initiation of X inactivation but may be involved in maintaining inactivation of those genes on the Xi. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Relative frequencies of homologous recombination between plasmids introduced into DNA repair-deficient and other mammalian somatic cell lines. Jul 1990 W P Wahls,P D Moore Twelve mammalian somatic cell lines, some of them DNA damage-sensitive mutants paired with their respective wild-type parental lines, were assayed for their ability to catalyze extrachromosomal, intermolecular homologous recombination between pSV2neo plasmid recombination substrates. All of the som... ( view more )atic cell lines analyzed are capable of catalyzing homologous recombination; however, there is a wide range of efficiencies with which they do so. Five human cell lines display a fourfold range of recombination frequencies, and six hamster cell lines vary almost 20-fold. Linearizing one of the recombination substrates stimulates recombination in all but one of the cell lines. Two of the three paired mutant cell lines display a threefold reduction in their ability to catalyze homologous recombination when compared to their respective parental cell lines, indicating that the mutations that render them sensitive to DNA damaging agents might also play a role in homologous recombination. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Somatic cell hybridization of Roberts syndrome and normal human fibroblasts transfected with plasmids carrying dominant selection markers. May 1987 J L Gunby,D J Tomkins,P L Chang Roberts syndrome (RS) is a rare human recessive disorder involving, in the chromosomes of some patients, a characteristic puffing or splitting apart of the constitutive heterochromatin (the RS effect). We carried out somatic cell hybridizations between an RS cell strain (R22) with the heterochromat... ( view more )in abnormality and a hypoxanthine phosphoribosyltransferase-deficient cell strain (GM1662) with normal chromosome structure to determine if the presence of the normal genome would correct the RS effect in the hybrid cells. In order to provide the fibroblast strains with dominant selection markers for the hybridizations, GM1662 was transfected with the plasmid pSV3neo which conferred resistance to the antibiotic G418, and R22 was transfected with the plasmid pSV3gpt which provided resistance to mycophenolic acid. Two somatic cell hybridizations were carried out: (1) R22 X GM1662 pSV3neo and (2) R22 pSV3gpt X GM1662 pSV3neo. The RS effect was found to be absent in 95% and 92%, respectively, of the 200 hybrid cells examined in each experiment. This indicated that the GM1662 genome was able to correct the RS effect. The presence of the RS effect in a few of the hybrid cells was attributed to the unstable karyotype resulting from pSV3 transfection which presumably caused the loss of the normal allele(s) of the RS gene in these hybrid cells. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Immunogenic variants obtained by mutagenesis of mouse mastocytoma P815. VII. Dominant expression of variant antigens in somatic cell hybrids. May 1983 J L Maryanski,J Szpirer,C Szpirer,T Boon After mutagenesis of mouse mastocytoma P815, it is possible to obtain at high frequency stable tumor cell variants (tum-) that are rejected by syngeneic DBA/2 mice. Most of the variants express one or more new individual antigens specific for each variant, that are detectable in vitro by cytolytic ... ( view more )T cells (CTL). Somatic hybrids were prepared either between tum- variants and the original P815 clone, or between different variants. Antigen expression of the hybrids was assessed by using long-term CTL clones that recognize specifically the new antigen present on the variants. Expression of tum- variant antigens behaved as a dominant trait in the hybrids. By submitting the somatic hybrids to selection with CTL clones, it was possible to obtain antigen-loss hybrid variants. The analyses of these antigen-loss variants showed that two variant-specific antigenic determinants associated with one of the variant fusion partners could be lost independently. Like the parental tum- variants, both the (tum+ X tum-) and (tum- X tum-) hybrids failed to form tumors in normal mice but formed tumors in irradiated mice. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Protein synthesis by rat hepatoma x mouse teratocarcinoma somatic cell hybrids. Jan 1983 L K Wray,H K Jaeckle The synthesis of intracellular and secretory proteins by rat hepatoma (MHC) and mouse teratocarcinoma (PCC4AZAl) cells and MHC X PCC4AZAl somatic cell hybrids was examined with two-dimensional (O'Farrell) electrophoresis. The gels of the PCC4AZAl and hybrid cells were nearly identical and were quit... ( view more )e different from those of the MHC cells. The teratocarcinoma phenotype was, therefore, dominant in the teratocarcinoma X hepatoma somatic cell hybrids. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Somatic cell genetic analysis of HLA-A, B, C and human beta 2-microglobulin expression. May 1982 M E Kamarck,J A Barbosa,F H Ruddle We have examined the cell surface expression of the human histocompatibility antigens HLA-A, B, C and beta 2-microglobulin (beta 2m) on a human-mouse somatic cell hybrid line. Using specific antibodies and the fluorescence-activated cell sorter (FACS), we viably fractionated and characterized four ... ( view more )separate hybrid subpopulations (HLA+,beta 2m+; HLA+,beta 2m-; HLA-,beta 2m+; HLA-,beta 2m-). Hybrid selection based on surface antigen expression resulted in corresponding genetic selection for and against human chromosomes 6 and 15. Studies of the homogeneous hybrid sublines revealed that the presence of human beta 2m in a hybrid cell dramatically increased the surface expression of human HLA-A, B, C and mouse H-2Kk antigens. The results demonstrate the importance of human chromosome-specific surface markers and the fluorescence-activated cell sorter in somatic cell genetic analysis. 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