Mech Ageing Dev
July 2003
The human aging diseases Werner and Bloom syndromes are a result of mutation of the WRN and BLM genes, respectively. The SGS1 gene of Saccharomyces cerevisiae is homologous to the human WRN and BLM genes of the RecQ DNA helicase family. Deletion of SGS1 results in accelerated yeast aging and a reduction in life span as well as cell cycle arrest.
View Article and Find Full Text PDFPurpose: An interval of six to eight weeks between completion of preoperative chemoradiation therapy and surgical resection of advanced rectal cancer has been described. Our purpose was to determine whether a longer time interval between completion of therapy and resection increases tumor downstaging and affects perioperative morbidity.
Methods: Forty patients with advanced adenocarcinoma of the rectum underwent preoperative chemoradiation on a prospective trial with irinotecan (50 mg/m2), 5-fluorouracil (225 mg/m2), and concomitant external-beam radiation (45-54 Gy) followed by complete surgical resection of the tumor with total mesorectal excision.
Background: The aim of this retrospective, case-matched controlled study was to determine the benefit of laparoscopic-assisted colectomy (LC) for the elderly (>75 years of age) and the young (<75 years of age) compared to an open colectomy (OC) control group.
Methods: A retrospective review of 39 patients older than 75 years of age and 38 patients younger than 75 years of age who underwent LC for colorectal cancer between 1991 and 1999 was performed. LC patients were matched with an open control group for procedure, age, gender, year of procedure, and surgeon.
Solid-state 19F nuclear magnetic resonance (NMR) spectroscopy is used for the quantitative investigation of accessible hydroxyl sites on low surface area glass fibers. Samples with surface areas as low as 0.2 m2/g are investigated through covalent binding of (3,3,3-trifluoropropyl)dimethylchlorosilane.
View Article and Find Full Text PDFScientific Committee 75 (SC 75) of the National Council on Radiation Protection and Measurements (NCRP) was assembled for the purpose of providing guidance to NASA concerning radiation protection in low-Earth orbit. The report of SC 75 was published in December 2000 as NCRP Report No. 132.
View Article and Find Full Text PDFThe complexity of radiation environments in space makes estimation of risks more difficult than for the protection of terrestrial populations. In deep space the duration of the mission, position in the solar cycle, number and size of solar particle events (SPE) and the spacecraft shielding are the major determinants of risk. In low-earth orbit missions there are the added factors of altitude and orbital inclination.
View Article and Find Full Text PDFPurpose: The aim of this trial was to evaluate the safety, efficacy, and impact on quality of life of the Acticon trade mark artificial bowel sphincter for fecal incontinence.
Methods: A multicenter, prospective, nonrandomized clinical trial was conducted under a common protocol. Patients were evaluated with anal physiology, endoanal ultrasonography, a fecal incontinence scoring system, fecal incontinence quality of life assessment, and overall health evaluation.
Here, we report the isolation and characterization of a strong dominant-negative phytochrome A (phyA) mutation (phyA-300D) in Arabidopsis. This mutation carries a single amino acid substitution at residue 631, from valine to methionine (V631M), in the core region within the C-terminal half of PHYA. This PHYA core region contains two protein-interactive motifs, PAS1 and PAS2.
View Article and Find Full Text PDFObjective: There is some evidence to suggest that workers in animal-related occupations are at increased risk of developing lymphohematopoietic cancers. This study aimed to examine the risk of leukemia, non-Hodgkin's lymphoma (NHL), and multiple myeloma associated with occupational exposure to animals.
Methods: We used data from a multi-site, population-based case-control study using mailed questionnaires which had taken place in eight of ten Canadian provinces, during 1994-1998.
Purpose: The aim of this study was to determine the effect of surgeon specialty on disease-free survival and local control in patients with adenocarcinoma of the rectum. Patients underwent curative treatment with neoadjuvant external beam radiotherapy and proctectomy by colorectal surgeons and noncolorectal surgeons.
Methods: The records of 384 consecutive patients treated by colorectal surgeons (n = 251) and noncolorectal surgeons (n = 133) from 1977 to 1995 were reviewed independently by physicians in the Division of Radiation Oncology.
Background: There is wide variability in reported locoregional recurrence rates after curative resection of adenocarcinoma of the intraperitoneal colon, and there is no universally accepted surgical technique regarding length of the resected specimen or extent of lymphadenectomy. The aim of this study was to determine the disease-free survival, locoregional failure, and perioperative morbidity of patients undergoing curative resection of colon adenocarcinoma.
Study Design: The records of 316 consecutive patients undergoing curative resection for primary adenocarcinoma of the intraperitoneal colon between 1990 and 1995 were reviewed.
Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominant genetic predisposition syndrome that accounts for 2-7% of all colorectal cancers. Diagnosis of HNPCC is based on family history (defined by Amsterdam or Bethesda Criteria), which often includes a history of multiple synchronous or metachronous cancers. The majority of HNPCC results from germ-line mutations in the DNA mismatch repair (MMR) genes hMSH2 and hMLH1 with rare alterations in hMSH6 and hPMS2 in atypical families.
View Article and Find Full Text PDFIntroduction: It is often stated that patients with colorectal carcinoid tumors have an increased risk of developing other malignancies. However, this risk has not been conclusively documented. A comprehensive evaluation is needed to more thoroughly assess the risk of second cancers in patients with colorectal carcinoids.
View Article and Find Full Text PDFMed Decis Making
March 2002
Background: This study examined obstetricians' decisions to perform or not to perform cesarean sections. The aim was to determine whether an artificial neural network could be constructed to accurately and reliably predict the birthing mode decisions of expert clinicians and to elucidate which factors were most important in deciding the birth mode.
Methods: Mothers with singleton, live births who were privately insured, nonclinic, non-Medicaid patients at a major tertiary care private hospital were included in the study (N = 1508).
Dis Colon Rectum
December 2001
Purpose: The aim of this study was to determine the survival rate, local failure, and perioperative morbidity in patients with adenocarcinoma of the rectum undergoing curative proctectomy who were felt to have transmural disease on preoperative assessment. Eighty-nine percent of these patients were treated with preoperative external beam radiotherapy.
Methods: The records of 191 consecutive patients undergoing abdominal surgical procedures for primary treatment of rectal cancer were reviewed.
Purpose: Endocavitary radiation (RT) provides a conservative alternative to proctectomy. Although most suitable for small, mobile lesions, patients with less favorable tumors are often referred if they are poor surgical candidates. Knowing the extent to which radiation can control such tumors can be an important factor in making clinical decisions.
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