Biomedical subjects

J M Wolf

Publications and source records attributed to J M Wolf.

11 recordsLinked to original sources

PubMed2005

The impact of ursodeoxycholic acid on cancer, dysplasia and mortality in ulcerative colitis patients with primary sclerosing cholangitis.

BACKGROUND: Colorectal cancer in primary sclerosing cholangitis patients with ulcerative colitis is mostly right-sided where concentrations of carcinogenic secondary bile acids are highest. AIM: To investigate whether ursodeoxycholic acid could be chemopreventive for colorectal cancer. METHODS: A historical cohort study was performed on primary sclerosing cholangitis patients with ulcerative colitis where the 28 patients (cases) who were treated with ursodeoxycholic acid for at least 6 months (mean 3.4 +/- 2.7 years) were compared with the 92 patients (controls) who were not treated with ursodeoxycholic acid. The primary outcomes were colorectal cancer and dysplasia. The secondary outcome was overall mortality. RESULTS: The cumulative incidence of dysplasia or cancer was not significantly different between cases and controls (P = 0.17 by log-rank test). The adjusted relative risk for cases of developing dysplasia or cancer was 0.59 (95% CI 0.26-1.36). The cumulative mortality was significantly different between groups (P = 0.02 by log-rank test). The adjusted relative risk for cases of death was 0.44 (95% CI 0.22-0.90). CONCLUSION: In ulcerative colitis patients with primary sclerosing cholangitis, ursodeoxycholic acid did not reduce the risk of developing cancer or dysplasia. However, ursodeoxycholic acid may reduce mortality.

Adult↗

PubMed2003

Impact of oral contraceptive use on glucocorticoid sensitivity of pro-inflammatory cytokine production after psychosocial stress.

We previously reported that women using oral contraceptives (OC) show blunted free cortisol responses to psychosocial stress compared to medication-free women. Low cortisol responses to stress have been shown to be associated with increased susceptibilities to chronic inflammatory and autoimmune processes in animal models and certain human diseases.To address the question if the blunted free cortisol response of OC users may be compensated at the level of the target tissue, we measured hypothalamus-pituitary-adrenal (HPA) axis activation and glucocorticoid (GC) sensitivity of pro-inflammatory cytokine production after psychosocial stress in 14 women using OC and 11 women in the luteal phase of the menstrual cycle. All subjects were exposed to the psychosocial stress paradigm 'Trier Social Stress Test' (TSST). Free cortisol was measured repeatedly before and after stress. GC sensitivity was assessed by dexamethasone (DEX) inhibition of lipopolysaccharide (LPS) stimulated production of interleukin-6 (IL-6) in whole blood, immediately before, as well as 10 and 60 min after the stress test. As expected, the stress test induced significant increases in free cortisol in luteal phase women, while OC users showed blunted responses (F=3.31;p<0.05). GC sensitivity showed different response patterns; In luteal phase women a slight but not significant decrease was observed throughout the experiment. In contrast, women using OC showed a significant increase in GC sensitivity after stress (F=3.559;p<0.05). These results show, that an increase in GC sensitivity of pro-inflammatory cytokine production may at least in part compensate the low cortisol levels seen in OC users after stress. This could be one mechanism to protect women using OC medication from chronic inflammatory and autoimmune diseases.

Adult↗

PubMed2001

Bone-retinaculum-bone reconstruction of scapholunate ligament injuries.

This article describes the indications for the use of a bone-retinaculum-bone autograft in soft tissue reconstruction of the torn scapholunate ligament. Specific surgical technique and postoperative management are highlighted. Initial results of a primary cohort of patients undergoing this technique are described. The technique is mainly indicated for patients with scapholunate ligament tears that are moderately easy to reduce by open methods.

Bone Transplantation↗

PubMed2001

Gadolinium inhibits thymidine incorporation and induces apoptosis in chondrocytes.

Magnetic resonance arthrography. a procedure where contrast agents containing gadolinium are administered intra-articularly, has become a useful tool in musculoskeletal diagnosis. Although considered safe for systemic use, toxicities in some tissues have been identified for both free gadolinium ion and the gadolinium chelates used as contrast. In this study, the effects of short-term exposure of articular chondrocytes to gadolinium contrast were examined by assaying for proteoglycan synthesis, cell proliferation, and apoptosis. Bovine chondrocytes were grown in monolayer culture and exposed to gadodiamide for 16 h. Proteoglycan synthesis was measured through incorporation of radiolabeled sulfate. Uptake of radiolabeled thymidine assessed cell proliferation. Apoptosis was detected using the TUNEL assay, where DNA strand breaks characteristic of apoptosis are labeled with fluorescent nucleotide. Proteoglycan synthesis was stimulated by lower dose exposure to gadodiamide. At higher doses, proteoglycan synthesis returned to baseline. Cell proliferation decreased following exposure to gadodiamide in a dose-dependent manner. Chondrocyte apoptosis was induced in a dose-dependent manner. Further work is needed to determine if these in vitro effects are present in the intact joint.

Animals↗

PubMed1999

Portable mini-fluoroscopy improves operative efficiency in hand surgery.

A paired case cohort study was performed using retrospective review of operative times for defined hand surgical procedures in an attempt to quantify efficiency with and without the use of portable fluoroscopy. Patients included in the study underwent 1 of 4 defined surgical procedures controlled to ensure similar operative technique (total wrist fusion, in situ 4-corner fusion, closed reduction/internal fixation using K-wires of phalangeal shaft fractures, and metacarpophalangeal or interphalangeal joint fusions using K-wires). One group used intraoperative standard film radiographs and the other used portable mini-fluoroscopy to examine hardware placement. Both groups were paired by operative procedure to eliminate procedure bias on overall operating time. Analysis demonstrated a 38% reduction in total operative time in the group using portable mini-fluoroscopy compared with standard intraoperative radiographs.

Arthrodesis↗

PubMed1988