PubMed Health⌕ Search

Biomedical subjects

A M Rijken

Publications and source records attributed to A M Rijken.

8 recordsLinked to original sources
PubMed2005

Emboli rate during and early after carotid endarterectomy after a single preoperative dose of 120 mg acetylsalicylic acid--a prospective double-blind placebo controlled randomised trial.

PURPOSE: To investigate whether a single pre-operative dose of 120 mg acetylsalicylic acid (ASA) decreased either (1) emboli rate, as detected by transcranial Doppler (TCD), during and early after carotid endarterectomy (CEA) and (2) clinical intra- and post-operative signs suggestive of embolism or increased bleeding tendency. DESIGN: Prospective, double-blind placebo controlled trial. PATIENTS AND METHODS: One-hundred consecutive patients were randomised to receive either 120 mg ASA (n = 48) or placebo (n = 49) by suppository on the night before CEA; three patients were excluded. Emboli were counted and expressed as emboli rate (ER). The incidence of bleeding complications was assessed. Surgeons were asked to indicate which patients had received ASA or placebo. RESULTS: There were no significant differences between the ASA and placebo groups in ER in the intraoperative and postoperative periods. ER higher than 0.9 min(-1) was associated with a significantly increased risk of complications (26 vs. 0%, P < 0.01). No extra bleeding complications were observed in the ASA group. Surgeon assessment of whether or not ASA had been administered had a sensitivity of 42% and a specificity of 70%. CONCLUSION: A single pre-operative dose of ASA (120 mg) did not reduce significantly the emboli rate during and after CEA and surgeons could not correctly identify whether or not ASA had been administered.

Aged↗
PubMed1999

p53 expression as a prognostic determinant in resected distal bile duct carcinoma.

AIMS: To determine the incidence and prognostic value of p53 immunopositivity in resectable distal bile duct carcinoma (DBDC). METHODS: Forty-seven paraffin-embedded archival tumour samples of patients with DBDC, who underwent subtotal pancreatoduodenectomy from 1985 to 1996, were immunohistochemically examined for p53 positivity, using the anti-p53 antibody D07. RESULTS: Nineteen (40%) of the 47 tumours demonstrated positive (>30%) p53 protein immunostaining. Focally positive or negative staining was seen in the remaining 28 (60%) cases. Patients in this low p53 category survived significantly longer than those in the high p53 category, with median survival durations of 29 and 13 months respectively (P=0. 039). p53 positivity was independent of age, sex, tumour size, radicality of resection, histopathological grading, lymph-node status, perineural invasion and vasoinvasive growth. CONCLUSIONS: This study indicates that low (0-30%) p53 expression is a favourable prognostic factor in patients with resected DBDC.

Adult↗
PubMed1999

Genomic alterations in distal bile duct carcinoma by comparative genomic hybridization and karyotype analysis.

We report genomic abnormalities identified in 14 human primary common bile duct carcinomas analyzed by cytogenetics or comparative genomic hybridization, or both. Combining the results of the two methods of analysis, 11 chromosomal arms were observed to be gained in whole or in part, and 9 chromosomal arms were lost in whole or in part in at least four tumors each. The most frequently lost chromosomal regions were, in decreasing order: 18q (eight tumors); 6q and 10p (seven tumors each); 8p, 12q, and 17p (six tumors each); and 7q, 12p, and 22q (four tumors each). The most frequently gained regions were 8q and 20q (six tumors each); 12p, 17q, and Xp (five tumors each); and 2q, 6p, 7p, 11q, 13q, and 19q (four tumors each). These results are similar to those we have previously reported in pancreatic cancer and suggest that carcinomas of the common bile duct and pancreas share a number of genetic changes.

Adult↗
PubMed1999

DNA quantitation of distal bile duct carcinoma measured by image and flow cytometry.

OBJECTIVE: To evaluate discrepancies between flow cytometry (FCM) and image cytometry (ICM), ploidy incidence and relation between DNA ploidies and survival in distal bile duct carcinomas (DBDCs). STUDY DESIGN: Forty-four archival tumor samples from patients with DBDC who underwent subtotal pancreatoduodenectomy from 1985 to 1996 were examined for DNA ploidy using FCM and ICM. RESULTS: Overall, 59% (26/44) of the tumors were aneuploid by at least one of the two techniques. We detected more cases of aneuploidy with ICM than FCM in formalin-fixed, paraffin-embedded DBDCs, 62% (21/34) versus 33% (13/40), respectively. When results could be compared, moderate strength of agreement (kappa = .45) was demonstrated. No correlation was found between DNA ploidy by FCM, ICM or combined FCM-ICM and survival time (P = .80, P = .35, and P = .54, respectively). CONCLUSION: Approximately 59% of DNA histograms contained aneuploid cell populations. Although ICM, as compared to FCM, is more sensitive in assessing the ploidy status of DBDC, both methods were complementary. Most discrepancies between FCM and ICM were due to the dilution of aneuploid populations by non-neoplastic diploid cells. DNA ploidy assessment in DBDC did not offer the possibility of improving the ability to predict survival.

Adult↗
PubMed1998

Diagnostic and prognostic value of incidence of K-ras codon 12 mutations in resected distal bile duct carcinoma.

BACKGROUND AND OBJECTIVES: The K-ras gene is one of the most extensively investigated oncogenes in a wide variety of human tumors, but has rarely been studied in distal bile duct carcinoma (DBDC). We sought to investigate the diagnostic and prognostic value of K-ras codon 12 mutations in this type of tumor. METHODS: Forty-seven patients who had undergone resection for DBDC were analyzed to reveal the incidence of K-ras codon 12 mutations, the locus most frequently involved. A rapid and simple two-step, semi-nested polymerase chain reaction (PCR) technique was used to detect mutations in paraffin-embedded tumor samples. RESULTS: The PCR mismatch amplification technique demonstrated that 35 (75%) of the 47 tumors harbored a point mutation in codon 12 of the K-ras oncogene. Patients with mutated tumors had no statistically different survival time compared to those patients without a mutation in the tumor. In contrast, negative microscopic margins proved to be a significant prognosticator. CONCLUSIONS: K-ras codon 12 mutations are common in DBDC and may be useful in the diagnosis and early detection of these tumors. However, no prognostic value of these mutations could be identified in this analysis. The results of this study also suggest that negative surgical margins remain the mainstay of prognostication in resectable DBDC. However, due to the small number of patients included in this study, the results obtained should be interpreted with care.

Adenocarcinoma↗
PubMed1998

Prognostic value of cell proliferation (Ki-67 antigen) and nuclear DNA content in clinically resectable, distal bile duct carcinoma.

BACKGROUND: The aim of this study was to investigate the prognostic value of cell proliferation (Ki-67 antigen) and DNA content in patients resected for distal bile duct carcinoma (DBDC). METHODS: Formalin-fixed tumor specimens of 35 patients with resected DBDC and a long-term clinical follow-up were analyzed. MIB-1 antibody was used for Ki-67 antigen detection to determine the proportion of proliferating cells. DNA content was measured using flow cytometry. RESULTS: A significant correlation was found between a low MIB-1 index (<20%) and survival (P <.05). Of the 35 tumor specimens, 34 specimens were evaluable by flow cytometry: 22 carcinomas were diploid (65%), and 12 were aneuploid (35%). The median DNA index of aneuploid tumors was 1.36 (range, 1.09 to 1.76). No correlation of DNA-ploidy with survival time was found. CONCLUSION: In contrast to DNA-ploidy pattern, Ki-67 antigen expression showed prognostic significance in resectable DBDC. A Ki-67 positive ratio of > or =20% was associated with decreased survival time.

Adult↗
PubMed1995

The modified Pirogoff amputation for traumatic partial foot amputations.

OBJECTIVE: To describe our experience with a modification of the Pirogoff amputation, in the treatment of serious injuries to the hind foot. DESIGN: Retrospective study. SETTING: University hospital, The Netherlands. SUBJECTS: Six patients who required amputation of the hind foot after serious injury. INTERVENTIONS: The modified Pirogoff amputation (amputation of the foot at the ankle with part of the calcaneus left in the lower end of the stump) was done four times as an emergency and twice electively between 1979 and 1991. RESULTS: All the patients were satisfied with their stumps at follow up (7 months-13 years). None had stump pain or phantom pain and they were able to walk about indoors without using the prosthesis. CONCLUSION: We recommend the Pirogoff amputation as the treatment of choice in the management of partial traumatic amputation and other injuries of the foot, should a transmetatarsal amputation be impossible and about 5 cm of the sole of the foot can be preserved.

Adult↗