Search PubMed⌕ Search

Biomedical subjects

R D Cohen

Publications and source records attributed to R D Cohen.

At least 37 records · Page 2Linked to original sources
PubMed2000

Infliximab in Crohn's disease: first anniversary clinical experience.

OBJECTIVE: The aim of this study is to report on the first year experience with infliximab for Crohn's disease. METHODS: All Crohn's patients receiving infliximab at our institution in the first year of release were prospectively registered. Disease activity was scored at initial infusion, and at 1, 3, 7, and 12 wk. Results were tabulated separately for patients with luminal (L) or fistulous (F) Crohn's disease. Steroid withdrawal and adverse events were tabulated. RESULTS: One hundred twenty-nine patients were treated (81 L, 48 F). Mean number of infusions/patient were 2.38 L, 3.23 F. Median time to response and remission was 8 and 9 days L; 9 and 10 days F, respectively. Initial infusion course response and remission rates at 3 wk were 65% and 31% L; 78% and 24% F, respectively. Rates were higher if concurrently treated with 6-mercaptopurine or azathioprine and improved with subsequent infusions. Relapse occurred in 78% at a mean 8.5 wk L and in 71% at a mean of 12.2 wk F. Steroid tapering was seen in >90%, with 54% completely off steroids after a second infusion. Infusion-related reactions were seen in up to 24% of patients. The incidence of side effects did not differ if on concurrent immunomodulatory therapy. CONCLUSIONS: Clinical experience with infliximab closely parallels the results of the controlled clinical trials, and includes steroid-sparing effects.

Adult↗
PubMed2000

Comparative strength of association between religious attendance and survival.

OBJECTIVE: Analyze effects on long-term survival of frequent religious attendance compared with four widely-accepted beneficial health behaviors. METHOD: Calculate gender-specific associations with mortality over 29 years for religious attendance, cigarette smoking, physical activity, alcohol consumption, and non-religious social involvement. Subjects were 5,894 participants in the Alameda County Study age 21-75. Analyses use proportional hazards modeling with time-dependent measures to adjust for subsequent changes in attendance and each health behavior over the follow-up period. All statistical models adjust for the same variables. RESULTS: For women, the protective effect of weekly religious attendance was of the same order of magnitude as the four other health behaviors. For men, the protective effect of weekly religious attendance was less than for any of the other health behaviors. CONCLUSIONS: The protective effect of religious attendance for women is comparable to those observed for several commonly recommended health behaviors: for men the protective effect of religious attendance is more modest. This strong gender difference may be a key to understanding how religious attendance exerts its effects.

Adult↗
PubMed2000

Standing at work and progression of carotid atherosclerosis.

OBJECTIVES: The association between the amount of standing at work and the progression of carotid intima media thickness (IMT) was studied among 584 active working men participating in the Kuopio Ischemic Heart Disease Risk Factor Study. METHODS: Ultrasound measurements of atherosclerotic changes in the carotid arteries were performed at the beginning of the study and after 4 years. Analyses of changes in IMT included adjustments for risk factors and stratification by base-line levels of atherosclerosis and prevalent ischemic heart disease (IHD). RESULTS: Significant relationships were found between the amount of standing at work and atherosclerotic progression. After adjustment for the heaviness of the work, psychosocial job factors, income, and biological and behavioral risk factors, the mean change in maximum IMT for those standing not at all, a little, a lot, and very much was 0.24, 0.25, 0.28, and 0.33 mm, respectively. For men with IHD the respective changes were 0.08, 0.15, 0.37, and 0.75 mm -- a 9-fold difference between the no-exposure and high-exposure group. For the men with carotid stenosis, the respective difference was 3-fold. CONCLUSIONS: These findings provide the first empirical support in a population study for the role of hemodynamic factors in the progression of atherosclerosis induced by long-term standing. Men with carotid stenosis or IHD appear especially vulnerable to the adverse effects associated with standing at work. Reducing the duration of standing at work should be considered both in the occupational rehabilitation of such patients and in the primary prevention of atherosclerosis.

Adult↗
PubMed2000

The role of laparoscopy and strictureplasty in the management of inflammatory bowel disease.

The surgical management of Crohn's disease has always been a challenging issue for physicians because of concerns of the historical need for repeated surgeries over time, the physiological limitations of a shortened small bowel, and the transmural, fistulizing, and/or skip-lesion nature of the disease. Patients are fearful of the potentially disfiguring results, especially the need for a permanent ostomy. The challenge has been to develop surgical approaches that are bowel sparing and/or minimally invasive. Stricutureplasty has been used with relatively good results as a bowel-sparing procedure for patients with small-bowel Crohn's disease, potentially sparing patients of a short-bowel syndrome. Laparoscopic approaches to Crohn's disease have thus far been mostly limited to ileocecal resections in selected patients, but as more expertise is developed, will hopefully be extended to other surgical procedures in patients with Crohn's disease in the future. Patient criteria, success rates, complications, and economic implications are discussed for each procedure.

Constriction, Pathologic↗
PubMed1999

Zonation of gluconeogenesis, ketogenesis and intracellular pH in livers from normal and diabetic ketoacidotic rats: evidence for intralobular redistribution of metabolic events in ketoacidosis.

The intralobular distribution of metabolism was examined in the livers from rats with severe diabetic ketoacidosis (DKA), perfused at pH 6.8, and compared with that in livers from normal starved animals perfused at either pH 7.4 or 6.8. With lactate and palmitate as substrates, the perivenous uptake of periportally synthesized glucose seen in normal livers at pH 7.4 was abolished during DKA; indeed, gluconeogenesis was most active in the perivenous region. Whereas in normal livers perfused at pH 7.4 the periportal region showed a markedly elevated intracellular pH (pH(i)) compared with the perivenous zone, this distribution of pH(i) was reversed in DKA, with an intermediate distribution in normal livers perfused at pH 6. 8. 3-Hydroxybutyrate was generated throughout the lobule. Some acetoacetate generated periportally was converted to 3-hydroxybutyrate more perivenously. A steep gradient of oxygen uptake along the radius of the lobule was apparent in all three groups; oxygen uptake was greatly decreased perivenously despite adequate oxygen supply. These findings are consistent with our previous observations of the lobular co-location of high pH(i) and gluconeogenesis, and might offer an explanation of how high gluconeogenic rates can continue in spite of severe systemic acidosis in DKA. The findings provide direct evidence for a marked redistribution of intralobular metabolism in DKA.

Animals↗
PubMed1999

Altered gene expression pattern in the fatty liver dystrophy mouse reveals impaired insulin-mediated cytoskeleton dynamics.

The mouse fatty liver dystrophy (fld) mutation is characterized by transient hypertriglyceridemia and fatty liver during the neonatal period, followed by development of a peripheral neuropathy. To uncover the metabolic pathway that is disrupted by the fld mutation, we analyzed the altered pattern of gene expression in the fatty liver of fld neonates by representational difference analysis of cDNA. Differentially expressed genes detected include a novel member of the Ras superfamily of small GTP-binding proteins, a novel Ser/Thr kinase, and several actin cytoskeleton-associated proteins including actin, profilin, alpha-actinin, and myosin light chain. Because these proteins have a potential functional link in the propagation of hormone signals, we investigated cytoskeleton dynamics in fld cells in response to hormone treatment. These studies revealed that preadipocytes from fld mice exhibit impaired formation of actin membrane ruffles in response to insulin treatment. These findings suggest that the altered mRNA expression levels detected in fld tissue represent a compensatory response for the nonfunctional fld gene and that the fld gene product may be required for development of normal insulin response.

Amino Acid Sequence↗
PubMed1999

Thalidomide therapy for patients with refractory Crohn's disease: an open-label trial.

BACKGROUND & AIMS: Inhibition of tumor necrosis factor is a proposed mechanism for the anti-inflammatory properties of thalidomide. We performed an open-label trial of thalidomide in refractory Crohn's disease. METHODS: Twenty-two patients with refractory Crohn's disease (Crohn's Disease Activity Index [CDAI] > 200 and/or draining perianal disease) initiated therapy with thalidomide, 200 mg at bedtime (18 patients), or 300 mg at bedtime (4 patients). CDAI and goal interval scores (GIS) were assessed at weeks 0, 4, and 12. Clinical response for patients with luminal disease was defined as reduction in CDAI score of >150 points and for fistula patients was 2 scores of >/=1+ in 3 parameters of the GIS. Clinical remission was defined as a total CDAI < 150 (luminal patients) or >/=2+ for all parameters of the GIS (fistula patients). RESULTS: Nine patients with luminal disease and 13 with fistulas (16 male, 6 female) were enrolled. The median CDAI score at entry was 371 (95-468). Sixteen patients completed 4 weeks of treatment (12 clinical responses, 4 clinical remissions). All 14 patients completing 12 weeks met criteria for clinical response. Nine achieved clinical remission (3 luminal, 6 fistula patients). The median CDAI score was 175 (30-468; P < 0.001 vs. baseline). CONCLUSIONS: Thalidomide is efficacious in some patients with refractory Crohn's disease.

Adult↗
PubMed1999

Primary laparoscopic-assisted endorectal colon pull-through for Hirschsprung's disease: a new gold standard.

OBJECTIVE: To describe the surgical technique and early clinical results after a one-stage laparoscopic-assisted endorectal colon pull-through for Hirschsprung's disease. SUMMARY BACKGROUND DATA: Recent trends in surgery for Hirschsprung's disease have been toward earlier repair and fewer surgical stages. A one-stage pull-through for Hirschsprung's disease avoids the additional anesthesia, surgery, and complications of a colostomy. A laparoscopic-assisted approach diminishes surgical trauma to the peritoneal cavity. METHODS: The technique uses four small abdominal ports. The transition zone is initially identified by seromuscular biopsies obtained laparoscopically. A colon pedicle preserving the marginal artery is fashioned endoscopically. The rectal mobilization is performed transanally using an endorectal sleeve technique. The anastomosis is performed transanally 1 cm above the dentate line. This report discusses the outcome of primary laparoscopic pull-through in 80 patients performed at six pediatric surgery centers over the past 5 years. RESULTS: The age at surgery ranged from 3 days to 96 months. The average length of the surgical procedure was 2.5 hours. Almost all of the patients passed stool and flatus within 24 hours of surgery. The average time for discharge after surgery was 3.7 days. All 80 patients are currently alive and well. Most of the children are too young to evaluate for fecal continence, but 18 of the older children have been reported to be continent. CONCLUSION: Laparoscopic-assisted colon pull-through appears to reduce perioperative complications and postoperative recovery time dramatically. The technique is quickly learned and has been performed in multiple centers with consistently good results.

Child↗
PubMed1999

A comparison of the quality of life in patients with severe ulcerative colitis after total colectomy versus medical treatment with intravenous cyclosporin.

Cyclosporin (CSA) has emerged as a medical alternative to colectomy in severe, steroid-refractory ulcerative colitis (UC) patients. This is the first formal quality-of-life study comparing such patients treated with intravenously administered cyclosporin with those treated surgically with colectomy. Quality-of-life analyses were conducted in all patients who underwent colectomy or received intravenous CSA for severe UC from 1991 to 1995 using the Inflammatory Bowel Disease Questionnaire, a visual-analog scale (VAS), and the Oresland scale, with additional questions regarding health care utilization and medication use. The 18 CSA-treated patients reported a better ability to sleep (p = 0.002; VAS), better stool consistency (p < 0.001; VAS), less abdominal or rectal pain (p = 0.009, VAS), and fewer daytime (p < 0.001; Oresland), nighttime (p = 0.006; Oresland), and daily trips to the toilet (p < 0.001; VAS) than the 46 surgical patients. The mean number and rate of hospitalizations within the first year was also lower in the CSA patients (p < 0.001 for both). The surgical patients reported fewer initial visits to their specialist (p < 0.001) and less medication use (p < 0.001; Oresland). Patients with severe steroid-refractory UC treated with intravenously administered CSA scored as well as or better than their surgical counterparts. The use of CSA in selected patients is substantiated both by clinical results and quality-of-life analysis.

Adult↗
PubMed1999

Intravenous cyclosporin in ulcerative colitis: a five-year experience.

OBJECTIVE: Cyclosporin (CSA) is a promising alternative for patients with severe steroid-refractory ulcerative colitis (UC) previously facing only surgical options. Concerns over the long term efficacy and side effects resulted in this investigation of the University of Chicago's 5-yr CSA experience in these patients. METHODS: All steroid-refractory severe ulcerative colitis (UC) patients treated with IV CSA from 1991 to 1995 were identified by using the university's IBD database, with additional information from patient charts and physician files. RESULTS: A total of 42 patients with severe UC unresponsive to IV steroids were treated with IV CSA (4 mg/kg/day). Of 42 patients, 36 (86%) responded; 31 were continued on oral CSA (8 mg/kg/day) for an overall mean of 20 wk. Ten initial CSA responders had colectomies after a mean of 6 months. Of the 36 initial responders, 25 (69%) also received 6-mercaptopurine (6-MP) or azathioprine (aza), and CSA and steroids were tapered. A total of 20% required colectomy, vs 45% of those not receiving 6MP/aza. In all, 62% of all patients, 72% of initial CSA responders, and 80% of initial CSA responders receiving 6MP/aza have avoided colectomy, with a life table analysis of "noncolectomy survival" of 58%, 70%, and 71%, respectively, at 5.5 yr. All colectomies occurred within 18 months of CSA initiation. Complications, resulting in CSA discontinuation in six patients, were all reversible, with complete recovery. CONCLUSIONS: CSA successfully allows most severe steroid resistant UC patients to retain their colons, and provides time for "elective" colectomy in others, especially if 6MP/aza are also given. Careful monitoring for side effects, including PCP prophylaxis, should be part of the treatment protocol.

Adolescent↗
PubMed1999

Validation of health-related quality of life instruments.

The development of instruments to quantitate health-related quality of life (HRQOL) includes taking the appropriate and, in fact, essential steps to ensure that the designated tool measures what it purports to measure and does it accurately and reliably. Such steps are not only critical in the development of appropriate tools, but, when clearly presented, also serve to prove to the reader (and reviewers) that the instrument is a legitimate one. Key to the development of any HRQOL instrument are three fundamental concepts: validity, reliability, and responsiveness. Validity proves that the instrument measures what it claims to measure. Reliability proves that the results are reproducible in a stable setting. Responsiveness proves that the instrument is sensitive enough to record important differences or changes. Each of these principles is discussed, including some examples of the application of these principles in previously published HRQOL studies. The studies referenced are excellent examples of the methods used in the creation of a HRQOL scale, and the reader is strongly encouraged to review these in their entirety to fully grasp the concepts.

Gastrointestinal Diseases↗
PubMed1998

Laparoscopic pull-through procedure for Hirschsprung's disease.

Contemporary surgical management of Hirschsprung's disease (HD) has evolved toward resection and reconstruction earlier in life. The introduction and miniaturization of laparoscopic instrumentation currently permits the application of this approach to the treatment of HD in the neonate. The authors' experience with this technique demonstrates several potential advantages over the "classical" two-stage operation.

Female↗
PubMed1998

Religiosity buffers effects of some stressors on depression but exacerbates others.

Although religiosity is protective for mortality and morbidity, its relationship with depression is unclear. We used the 1994 Alameda County Study survey of 2,537 subjects aged 50-102 to analyze associations between two forms of religiosity and depression as well as the extent to which religiosity buffers relationships between stressors and depression. Non-organizational religiosity included prayer and importance of religious and spiritual beliefs; organizational religiosity included attendance at services and other activities. Non-organizational religiosity had no association with depression; organizational religiosity had a negative relationship that weakened slightly with the addition of health controls. Both forms of religiosity buffered associations with depression for non-family stressors, such as financial and health problems. However, non-organizational religiosity exacerbated associations with depression for child problems, and organizational religiosity exacerbated associations with depression for marital problems, abuse, and caregiving. Religiosity may help those experiencing non-family stressors, but may worsen matters for those facing family crises.

Aged↗
PubMed1998

Income inequality and mortality in metropolitan areas of the United States.

OBJECTIVES: This study examined associations between income inequality and mortality in 282 US metropolitan areas. METHODS: Income inequality measures were calculated from the 1990 US Census. Mortality was calculated from National Center for Health Statistics data and modeled with weighted linear regressions of the log age-adjusted rate. RESULTS: Excess mortality between metropolitan areas with high and low income inequality ranged from 64.7 to 95.8 deaths per 100,000 depending on the inequality measure. In age-specific analyses, income inequality was most evident for infant mortality and for mortality between ages 15 and 64. CONCLUSIONS: Higher income inequality is associated with increased mortality at all per capita income levels. Areas with high income inequality and low average income had excess mortality of 139.8 deaths per 100,000 compared with areas with low inequality and high income. The magnitude of this mortality difference is comparable to the combined loss of life from lung cancer, diabetes, motor vehicle crashes, human immunodeficiency virus (HIV) infection, suicide, and homicide in 1995. Given the mortality burden associated with income inequality, public and private sector initiatives to reduce economic inequalities should be a high priority.

Adolescent↗
PubMed1998

Ischemic heart disease and stroke mortality in African-American, Hispanic, and non-Hispanic white men and women, 1985 to 1991.

We compare recent trends in ischemic heart disease (IHD) and stroke mortality in California among the 6 major sex-racial or -ethnic groups. Rates of age-specific and -adjusted mortality were calculated for persons aged 35 and older during the years 1985 to 1991. Log-linear regression modeling was performed to estimate the average annual percentage change in mortality. During 1985 through 1991, the mortality for IHD and stroke was generally highest for African Americans, intermediate for non-Hispanic whites, and lowest for Hispanics. Age-adjusted mortality for IHD declined significantly in all sex-racial or -ethnic groups except African-American women, and stroke rates declined significantly in all groups except African-American and Hispanic men. African Americans had excess IHD mortality relative to non-Hispanic whites until late in life, after which mortality of non-Hispanic whites was higher. Similarly, African Americans and Hispanics had excess stroke mortality relative to non-Hispanic whites early in life, whereas stroke mortality in non-Hispanic whites was higher at older ages. The lower IHD and stroke mortality among Hispanics was paradoxical, given the generally adverse risk profile and socioeconomic status observed among Hispanics. An alarmingly high prevalence of self-reported cardiovascular disease risk factors in 1994 to 1996, particularly hypertension, leisure-time sedentary lifestyle, and obesity, is a serious public health concern, with implications for future trends in cardiovascular disease mortality. Of particular concern was the growing disparities in stroke and IHD mortality among younger-aged African Americans relative to Hispanics and non-Hispanic whites.

Adolescent↗