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11.
Sau W Cheung Chad A Shaw Wei Yu Jiangzham Li Zhishuo Ou Ankita Patel Svetlana A Yatsenko Mitchell L Cooper Patti Furman Pawel Stankiewicz Pawal Stankiewicz James R Lupski A Craig Chinault Arthur L Beaudet 《Genetics in medicine》2005,7(6):422-432
PURPOSE: We developed a microarray for clinical diagnosis of chromosomal disorders using large insert genomic DNA clones as targets for comparative genomic hybridization (CGH). METHODS: The array contains 362 FISH-verified clones that span genomic regions implicated in over 40 known human genomic disorders and representative subtelomeric clones for each of the 41 clinically relevant human chromosome telomeres. Three or four clones from almost all deletion or duplication genomic regions and three or more clones for each subtelomeric region were included. We tested chromosome microarray analysis (CMA) in a masked fashion by examining genomic DNA from 25 patients who were previously ascertained in a genetic clinic and studied by conventional cytogenetics. A novel software package implemented in the R statistical programming language was developed for normalization, visualization, and inference. RESULTS: The CMA results were entirely consistent with previous cytogenetic and FISH findings. For clone by clone analysis, the sensitivity was estimated to be 96.7% and the specificity was 99.1%. Major advantages of this selected human genome array include the following: interrogation of clinically relevant genomic regions, the ability to test for a wide range of duplication and deletion syndromes in a single analysis, the ability to detect duplications that would likely be undetected by metaphase FISH, and ease of confirmation of suspected genomic changes by conventional FISH testing currently available in the cytogenetics laboratory. CONCLUSION: The array is an attractive alternative to telomere FISH and locus-specific FISH, but it does not include uniform coverage across the arms of each chromosome and is not intended to substitute for a standard karyotype. Limitations of CMA include the inability to detect both balanced chromosome changes and low levels of mosaicism. 相似文献
12.
High prevalence of HPV 16 in South African women with cancer of the cervix and cervical intraepithelial neoplasia 总被引:9,自引:0,他引:9
Kay P Soeters R Nevin J Denny L Dehaeck CM Williamson AL 《Journal of medical virology》2003,71(2):265-273
Despite the high prevalence of cervical cancer and cervical neoplasias in South Africa, few studies have been performed in this region to establish which human papillomavirus (HPV) types are associated with the development of high-grade cervical intraepithelial neoplasia lesions and cervical cancer. To investigate these prevalence rates, punch biopsies were obtained from 56 women with cervical cancer and 141 women with histologically diagnosed cervical intraepithelial neoplasia 2 or 3 lesions. Nested polymerase chain reaction (PCR) using consensus degenerate PCR primers was performed for the detection of HPV DNA and HPV typing was done by restriction fragment length polymorphism. Forty-seven (94%) of the cervical cancer and 114 (88%) of the cervical intraepithelial neoplasia 2/3 biopsies were positive for HPV DNA. The prevalence rates of the HPV types detected in the cervical cancer biopsies were HPV 16 (82%), HPV 18, (10%), HPV 33 (10%), HPV 31 (2%), HPV 58 (2%), HPV 35 (2%), and HPV 59 (2%). The cervical intraepithelial neoplasia lesions contained HPV 16 (56.6%), HPV 33 (14%), HPV 31 (10.9%), HPV X (7%), HPV 52 (3.9), HPV 58 (3.1%), HPV 35 (2.3%), HPV 18 (1.6%), HPV 11 (0.8%). Five of the nine fragments that were not typed by the RFLP, designated HPV-X, were sequenced to give HPV6 (1/5), HPV 26 (2/5), HPV 68 (1/5), and candHPV 87 (1/5). HPV 58 was detected in one cervical cancer biopsy and four biopsies from cervical intraepithelial neoplasia grade 3 lesions and was shown to be a previously described variant [Williamson and Rybicki (1991) J. Med. Virol. 33:165-171]. In addition, a cervical intraepithelial neoplasia grade 2 lesion was shown to harbour HPV type HAN2294 (cand HPV 87). The results of this study indicate that cervical cancer and cervical intraepithelial neoplasia 2/3 are largely associated with HPV 16 infection in this group of South African women and, therefore, an effective HPV 16 based vaccine should prevent the development of cervical cancer in a large proportion of women from this region of South Africa. 相似文献
13.
Jevitt LA Smith AJ Williams PP Raney PM McGowan JE Tenover FC 《Microbial drug resistance (Larchmont, N.Y.)》2003,9(4):389-393
We assessed the in vitro activities of daptomycin, linezolid, and quinupristin-dalfopristin (QD) against a contemporary challenge panel of 88 staphylococcal and 90 enterococcal isolates. The staphylococci selected included vancomycin-intermediate Staphylococcus aureus (VISA), methicillin-resistant S. aureus, and coagulasenegative staphylococci. Enterococcal isolates included vancomycin-resistant Enterococcus faecium (VREF) containing either vanA, vanB1, or vanD. The MICs of daptomycin, linezolid, and QD were determined using commercial broth microdilution panels. All three VISA isolates were susceptible to daptomycin, linezolid, and QD. QD was the most active agent against staphylococcal isolates (MIC50 < or = 0.5 microg/ml and MIC90 = 1 microg/ml), including those with decreased susceptibility to vancomycin. QD was also the most active agent against VREF (MIC90 < or = 0.5 microg/ml). No differences were seen for susceptibility of vanA, vanB1, and vanD VREF strains for daptomycin, linezolid, or QD. Daptomycin was the most effective against E. faecalis. On the basis of manufacturer-suggested interpretive criteria, 92% of isolates were susceptible (MIC90 = 4 microg/ml). All isolates tested were susceptible to at least one antimicrobial agent for which interpretive criteria have been defined. Population analysis of three S. aureus isolates for which the daptomycin MICs were 8 microg/ml showed a pattern of homogeneous resistance. 相似文献
14.
Morgante L Salemi G Meneghini F Di Rosa AE Epifanio A Grigoletto F Ragonese P Patti F Reggio A Di Perri R Savettieri G 《Archives of neurology》2000,57(4):507-512
OBJECTIVE: To evaluate whether the survival of patients with Parkinson disease (PD) is shorter than that of the general population. DESIGN: Survival was investigated in a cohort of patients with PD previously identified during a population-based prevalence study (prevalence day, November 1, 1987, reference follow-up date, October 31, 1995). The survival of patients with PD was compared with that of a control sample randomly selected from the same population (2 controls for each case, matched for age, sex, and study municipality). The causes of death in the 2 groups were also compared. Both univariate and multivariate survival analyses were performed to investigate the association with disease-related variables. SETTING: A door-to-door 2-phase prevalence survey performed in 3 Sicilian municipalities. PATIENTS: Fifty-nine patients with PD and 118 controls. RESULTS: Patients with PD showed a high risk of death (relative risk, 2.3; 95% confidence interval, 1.60-3.39). Greater age at November 1, 1987, high Hoehn-Yahr score, and lack of levodopa therapy were associated with a lower survival on univariate analysis. Multivariate analysis confirmed the association between shorter survival among patients with PD and greater age on November 1, 1987. One-way analysis of variance indicated a different effect of levodopa therapy according to age. Multivariate analysis did not confirm this finding. Pneumonia was the cause of death most frequently associated with PD. CONCLUSION: This study indicates that patients with PD have a shorter survival time than the general population. 相似文献
15.
A Olivieri G Santini C Patti T Chisesi C De Souza A Rubagotti S Aversa A Billio A Porcellini M Candela R Centurioni A M Congiu M Brunori S Nati M Spriano R Vimercati G Marino A Contu L Tedeschi I Majolino M Crugnola M R Sertoli 《Annals of oncology》2005,16(12):1941-1948
BACKGROUND: There is not univocal concordance for using high-dose sequential therapy (HDS) as first-line treatment for aggressive non-Hodgkin's lymphoma (NHL). We designed this study to evaluate the usefulness of HDS followed by high-dose therapy (HDT) with autologous stem cell transplantation as front-line treatment in different subsets of aggressive NHL. PATIENTS AND METHODS: Among 223 patients aged 15-60 years with aggressive, advanced stage NHL, 106 patients were randomized to VACOP-B (etoposide, doxorubicin, cyclophosphamide, vincristine, prednisone, bleomycin) for 12 weeks (plus HDS/HDT in case of persistent disease) (arm A), and 117 patients to VACOP-B for 8 weeks plus upfront HDS/HDT (arm B). RESULTS: According to the intention-to-treat analysis, the complete response rate was 75% for arm A and 72.6% for arm B. With a median follow-up of 62 months there was no difference in 7-year probability of survival (60% and 57.8%; P = 0.5), disease-free survival (DFS) (62% and 71%; P = 0.2) and progression-free survival (PFS) (44.9% and 40.9%; P = 0.7) between the two arms. Subgroup analyses confirmed that the best results in terms of survival, DFS and PFS were achieved by patients with large B-cell NHL without bone marrow (BM) involvement, independently of the treatment arm. Results were poorer in other categories of patients and poorest in patients with BM involvement. CONCLUSIONS: Aggressive NHL patients do not benefit from upfront HDS/HDT. 相似文献
16.
17.
Salvatore Iovino Alison M. Burkart Kristina Kriauciunas Laura Warren Katelyn J. Hughes Michael Molla Youn-Kyoung Lee Mary-Elizabeth Patti C. Ronald Kahn 《Diabetes》2014,63(12):4130-4142
Insulin resistance is central to diabetes and metabolic syndrome. To define the consequences of genetic insulin resistance distinct from those secondary to cellular differentiation or in vivo regulation, we generated induced pluripotent stem cells (iPSCs) from individuals with insulin receptor mutations and age-appropriate control subjects and studied insulin signaling and gene expression compared with the fibroblasts from which they were derived. iPSCs from patients with genetic insulin resistance exhibited altered insulin signaling, paralleling that seen in the original fibroblasts. Insulin-stimulated expression of immediate early genes and proliferation were also potently reduced in insulin resistant iPSCs. Global gene expression analysis revealed marked differences in both insulin-resistant iPSCs and corresponding fibroblasts compared with control iPSCs and fibroblasts. Patterns of gene expression in patients with genetic insulin resistance were particularly distinct in the two cell types, indicating dependence on not only receptor activity but also the cellular context of the mutant insulin receptor. Thus, iPSCs provide a novel approach to define effects of genetically determined insulin resistance. This study demonstrates that effects of insulin resistance on gene expression are modified by cellular context and differentiation state. Moreover, altered insulin receptor signaling and insulin resistance can modify proliferation and function of pluripotent stem cell populations. 相似文献
18.
19.
In this research study we have developed a clustering‐based automatic sleep spindle detection method that was evaluated on two different databases. The databases consisted of 20 all‐night polysomnograph recordings. Past detection methods have been based on subject‐independent and some subject‐dependent parameters, such as fixed or variable thresholds to identify spindles. Using a multivariate Gaussian mixture model clustering technique, our algorithm was developed to use only subject‐specific parameters to detect spindles. We have obtained an overall sensitivity range (65.1–74.1%) at a (59.55–119.7%) false positive proportion. 相似文献
20.
David G. Cotter Baris Ercal Xiaojing Huang Jamison M. Leid D. André d’Avignon Mark J. Graham Dennis J. Dietzen Elizabeth M. Brunt Gary J. Patti Peter A. Crawford 《The Journal of clinical investigation》2014,124(12):5175-5190
Nonalcoholic fatty liver disease (NAFLD) spectrum disorders affect approximately 1 billion individuals worldwide. However, the drivers of progressive steatohepatitis remain incompletely defined. Ketogenesis can dispose of much of the fat that enters the liver, and dysfunction in this pathway could promote the development of NAFLD. Here, we evaluated mice lacking mitochondrial 3-hydroxymethylglutaryl CoA synthase (HMGCS2) to determine the role of ketogenesis in preventing diet-induced steatohepatitis. Antisense oligonucleotide–induced loss of HMGCS2 in chow-fed adult mice caused mild hyperglycemia, increased hepatic gluconeogenesis from pyruvate, and augmented production of hundreds of hepatic metabolites, a suite of which indicated activation of the de novo lipogenesis pathway. High-fat diet feeding of mice with insufficient ketogenesis resulted in extensive hepatocyte injury and inflammation, decreased glycemia, deranged hepatic TCA cycle intermediate concentrations, and impaired hepatic gluconeogenesis due to sequestration of free coenzyme A (CoASH). Supplementation of the CoASH precursors pantothenic acid and cysteine normalized TCA intermediates and gluconeogenesis in the livers of ketogenesis-insufficient animals. Together, these findings indicate that ketogenesis is a critical regulator of hepatic acyl-CoA metabolism, glucose metabolism, and TCA cycle function in the absorptive state and suggest that ketogenesis may modulate fatty liver disease. 相似文献