Biomedical subjects

Ulrich T Hopt

Publications and source records attributed to Ulrich T Hopt.

23 records · Page 2Linked to original sources

PubMed2002

Biomaterial implants induce the inflammation marker CRP at the site of implantation.

Following implantation of biomaterial patches into the gastrointestinal tract, we analyzed the host's response towards the foreign material. Asymmetric patches of polydioxanone covered Vicryl or poly-3-hydroxybutyrate were sutured onto the rat stomach. Tissue samples were generated at distinct time intervals after surgery, and RNA profiles were compared by Differential Display. RT-PCR analysis of gene candidates that seemed differentially expressed showed that vitamin D binding protein mRNA was induced in stomach tissue after implantation of the biomaterial patches. In parallel, the amount of C-reactive protein mRNA was found to be increased transiently as well. Implants induce a tissue response that is specific for a given material.

Absorbable Implants↗

PubMed2002

Biomaterial patches sutured onto the rat stomach induce a set of genes encoding pancreatic enzymes.

Asymmetric patches of polyhydroxybutyric acid with one smooth and one rough surface were produced by a dipping procedure. These patches were implanted into the rat gastrointestine and tissue samples were generated at distinct time intervals after surgery. The host's response towards the foreign material was analyzed by Differential Display and RNA profiles were compared to each other. One to two weeks after surgery a group of mRNAs encoding pancreatic enzymes was transiently present after biomaterial implantation.

Animals↗

PubMedDate not supplied

Postoperative morbidity and long-term survival after pancreaticoduodenectomy with superior mesenterico-portal vein resection.

The role of superior mesenteric-portal vein resection (SM-PVR) for vein invasion or tumor adherence during pancreatoduodenectomy (PD) is still under debate. We investigated morbidity, mortality, and long-term survival in patients who underwent PD with or without SM-PVR. Between July 1994 and December 2004, 222 PD (78% pylorus preserving, 19% Whipple, and 3% total pancreatectomy) were performed for malignant disease. Fifty-three patients (24%) had PD with SM-PVR. Sixty-eight percent of the venous resections were performed as wedge excisions and 32% as segmental resections. Long-term survival was analyzed in 165 patients with pancreatic (n = 110), ampullary (n = 33), or distal bile (n = 22) duct cancer using univariate (log-rank) and multivariate (Cox regression) methods. In patients undergoing PD with SM-PVR and conclusive histologic examination of the resected vein specimen (n = 42), 60% had true tumor involvement of the venous wall, whereas 40% had no proven tumor infiltration. In the complete study group, negative resection margins were obtained in 69% of patients with SM-PVR and in 79% of patients without SM-PVR (P = 0.09). Median duration of surgery was 500 minutes (SM-PVR) versus 440 minutes (no SM-PVR; P < 0.001). Volume of intraoperatively transfused blood was 600 ml (median) in both groups. Postoperative surgical complications/mortality occurred in 23%/3.8% (SM-PVR) versus 35%/4.1% (no SM-PVR); P = 0.09/0.9. Analysis of long-term survival in all 165 patients included 41 with SM-PVR. Five-year survival rates were 15% in cancer of the pancreatic head, 22% in ampullary cancer, and 24% in distal bile duct cancer (P = 0.02). Long-term survival was not influenced by the need for SM-PVR in any of the different tumor entities. In multivariate analysis, a positive resection margin (P < 0.01, relative risk [RR]: 1.8, 95% confidence interval [CI]: 1.2-2.7), a histologically undifferentiated tumor (P = 0.01, RR: 1.7, 95% CI: 1.1-2.5), and the tumor entity (P < 0.01) were significant predictors of survival. Univariate survival analysis of the 110 patients with cancer of the pancreatic head revealed that a histologically undifferentiated tumor (P = 0.05) and positive resection margins (P = 0.02) were associated with a poorer survival. In multivariate analysis, the resection margin (P = 0.02, RR: 5.1, 95% CI: 1.1-2.8) and a histologically undifferentiated tumor (P = 0.05, RR: 3.8, 95% CI: 1.0-2.5) significantly influenced survival. After PD, perioperative morbidity and long-term survival in patients with SM-PVR were similar to those of patients without vein resection. In case of tumor adherence or infiltration, combined resection of the pancreatic head and the vein should always be considered in the absence of other contraindications for resection.

Adolescent↗

PubMedDate not supplied

Delayed gastric emptying after pylorus-preserving pancreatoduodenectomy is strongly related to other postoperative complications.

Patients undergoing pylorus-preserving pancreatoduodenenectomy (PPPD) have a risk of up to 50% for developing delayed gastric emptying (DGE) in the early postoperative course. From 1994 to August 2002, a total of 204 patients underwent PPPD for pancreatic or periampullary cancer (50%), chronic pancreatitis (42%), and other indications (8%). Retrocolic end-to-side duodenojejunostomy was performed below the mesocolon. DGE was defined by the inability to tolerate a regular diet after day 10 (DGE10) or day 14 (DGE14) postoperatively, as well as the need for a nasogastric tube at or beyond day 10 (DGE10GT). Postoperative morbidity was 38%, 30-day mortality was 2.9%, and median postoperative length of stay was 15 days. DGE occurred in 14.7% (DGE10), 5.9% (DGE14), and 6.4% (DGE10GT), respectively. After further exclusion of 21 patients (10.3%) with major complications and no possible oral intake (because of death, reoperation, or mechanical ventilation), the frequencies of DGE10, DGE14, and DGE10GT in the remaining group of 183 patients were 9%, 2%, and 2%, respectively. Multivariate analysis revealed postoperative complications (P<0.001), the presence of portalvenous hypertension (P<0.01), and tumors as indications for surgery (P<0.01) as independent risk factors for DGE10. The overall incidence of DGE was low after PPPD. In those patients experiencing DGE, however, other postoperative complications were the most important factor associated with its occurrence.

Adult↗

PubMedDate not supplied

Cytokine expression in colon carcinoma.

BACKGROUND: Cytokines reflect the activity of the immune system. We analyzed the local expression of characteristic cytokines indicating the level of activity of unspecific inflammatory cells, Th1-cells and Th2-cells in colon cancer. MATERIALS AND METHODS: In 25 tumor/ mucosa pairs, IL-1alpha, IL-2, IL-4, IL-5, IL-15, TNF-alpha and IFN-gamma were measured by real-time PCR. RESULTS: There was a significant increase in IL-1alpha, IL-4, IL-5 and TNF-alpha and a significant decrease in IL-2 in tumor tissue compared to normal mucosa. DISCUSSION: The cytokine profile in colon cancer indicates a strong unspecific inflammatory reaction in the tumor tissue represented by high levels of IL-1 and TNF-alpha. The comparatively low level of IL-2 suggests suppression of a specific immunological reaction, namely Th1-cells. It can be hypothesized that this is a result and/or cause of local immune escape mechanisms. Furthermore, there is an activation of TH2 cells in the carcinomas.

Adenocarcinoma↗