Expression of dihydropyrimidine dehydrogenase (DPD) and hENT1 predicts survival in pancreatic cancer.

BACKGROUND: Dihydropyrimidine dehydrogenase (DPD) tumour expression may provide added value to human equilibrative nucleoside transporter-1 (hENT1) tumour expression in predicting survival following pyrimidine-based adjuvant chemotherapy. METHODS: DPD and hENT1 immunohistochemistry and scoring was completed on tumour cores from 238 patients with pancreatic cancer in the ESPAC-3(v2) trial, randomised to either postoperative gemcitabine or 5-fluorouracil/folinic acid (5FU/FA). RESULTS: DPD tumour expression was associated with reduced overall survival (hazard ratio, HR = 1.73 [95% confidence interval, CI = 1.21-2.49], p = 0.003). This was significant in the 5FU/FA arm (HR = 2.07 [95% CI = 1.22-3.53], p = 0.007), but not in the gemcitabine arm (HR = 1.47 [0.91-3.37], p = 0.119). High hENT1 tumour expression was associated with increased survival in gemcitabine treated (HR = 0.56 [0.38-0.82], p = 0.003) but not in 5FU/FA treated patients (HR = 1.19 [0.80-1.78], p = 0.390). In patients with low hENT1 tumour expression, high DPD tumour expression was associated with a worse median [95% CI] survival in the 5FU/FA arm (9.7 [5.3-30.4] vs 29.2 [19.5-41.9] months, p = 0.002) but not in the gemcitabine arm (14.0 [9.1-15.7] vs. 18.0 [7.6-15.3] months, p = 1.000). The interaction of treatment arm and DPD expression was not significant (p = 0.303), but the interaction of treatment arm and hENT1 expression was (p = 0.009). CONCLUSION: DPD tumour expression was a negative prognostic biomarker. Together with tumour expression of hENT1, DPD tumour expression defined patient subgroups that might benefit from either postoperative 5FU/FA or gemcitabine.

Intratumoural expression of deoxycytidylate deaminase or ribonuceotide reductase subunit M1 expression are not related to survival in patients with resected pancreatic cancer given adjuvant chemotherapy.

BACKGROUND: Deoxycytidylate deaminase (DCTD) and ribonucleotide reductase subunit M1 (RRM1) are potential prognostic and predictive biomarkers for pyrimidine-based chemotherapy in pancreatic adenocarcinoma. METHODS: Immunohistochemical staining of DCTD and RRM1 was performed on tissue microarrays representing tumour samples from 303 patients in European Study Group for Pancreatic Cancer (ESPAC)-randomised adjuvant trials following pancreatic resection, 272 of whom had received gemcitabine or 5-fluorouracil with folinic acid in ESPAC-3(v2), and 31 patients from the combined ESPAC-3(v1) and ESPAC-1 post-operative pure observational groups. RESULTS: Neither log-rank testing on dichotomised strata or Cox proportional hazard regression showed any relationship of DCTD or RRM1 expression levels to survival overall or by treatment group. CONCLUSIONS: Expression of either DCTD or RRM1 was not prognostic or predictive in patients with pancreatic adenocarcinoma who had had post-operative chemotherapy with either gemcitabine or 5-fluorouracil with folinic acid.

Venous thromboembolism following colorectal resection.

AIM: The study investigated the rate of significant venous thromboembolism (VTE) following colorectal resection during the index admission and over 1 year following discharge. It identifies risk factors associated with VTE and considers the length of VTE prophylaxis required. METHOD: All adult patients who underwent colorectal resections in England between April 2007 and March 2008 were identified using Hospital Episode Statistics data. They were studied during the index admission and followed for a year to identify any patients who were readmitted as an emergency with a diagnosis of deep venous thrombosis or pulmonary embolism. RESULTS: In all, 35 997 patients underwent colorectal resection during the period of study. The VTE rate was 2.3%. Two hundred and one (0.56%) patients developed VTE during the index admission and 571 (1.72%) were readmitted with VTE. Following discharge from the index admission, the risk of VTE in patients with cancer remained elevated for 6 months compared with 2 months in patients with benign disease. Age, postoperative stay, cancer, emergency admission and emergency surgery for patients with inflammatory bowel disease (IBD) were all independent risk factors associated with an increased risk of VTE. Patients with ischaemic heart disease and those having elective minimal access surgery appear to have lower levels of VTE. CONCLUSION: This study adds to the benefits of minimal access surgery and demonstrates an additional risk to patients undergoing emergency surgery for IBD. The majority of VTE cases occur following discharge from the index admission. Therefore, surgery for cancer, emergency surgery for IBD and those with an extended hospital stay may benefit from extended VTE prophylaxis. This study demonstrates that a stratified approach may be required to reduce the incidence of VTE.

Bile duct reconstruction following laparoscopic cholecystectomy in England.

OBJECTIVES: To determine the incidence of bile duct reconstruction (BDR) following laparoscopic cholecystectomy (LC) and to identify associated risk factors. BACKGROUND: Major bile duct injury (BDI) requiring reconstruction is a serious complication of cholecystectomy. METHODS: All LC and attempted LC operations in England between April 2001 and March 2013 were identified. Patients with malignancy, a stone in bile duct or those who underwent bile duct exploration were excluded. This cohort of patients was followed for 1 year to identify those who underwent BDR as a surrogate marker for major BDI. Logistic regression was used to identify factors associated with the need for reconstruction. RESULTS: In total, 572,223 LC and attempted LC were performed in England between April 2001 and March 2013. Five hundred (0.09 %) of these patients underwent BDR. The risk of BDR is lower in patient that do not have acute cholecystitis [odds ratio (OR) 0.48 (95 % CI 0.30-0.76)]. The regular use of on-table cholangiography (OTC) [OR 0.69 (0.54-0.88)] and high consultant caseload >80 LC/year [OR 0.56 (0.39-0.54)] reduced the risk of BDR. Patients who underwent BDR were 10 times more likely to die within a year than those who did not require further surgery (6 vs. 0.6 %). CONCLUSIONS: The rate of BDR following laparoscopic cholecystectomy in England is low (0.09 %). The study suggests that OTC should be used more widely and provides further evidence in support of the provision of LC services by specialised teams with an adequate caseload (>80).

Posttranslational modifications of alpha-tubulin: acetylated and detyrosinated forms in axons of rat cerebellum.

The distribution of acetylated alpha-tubulin in rat cerebellum was examined and compared with that of total alpha-tubulin and tyrosinated alpha-tubulin. From immunoperoxidase-stained vibratome sections of rat cerebellum it was found that acetylated alpha-tubulin, detectable with monoclonal 6-11B-1, was preferentially enriched in axons compared with dendrites. Parallel fiber axons, in particular, were labeled with 6-11B-1 yet unstained by an antibody recognizing tyrosinated alpha-tubulin, indicating that parallel fibers contain alpha-tubulin that is acetylated and detyrosinated. Axonal microtubules are known to be highly stable and the distribution of acetylated alpha-tubulin in other classes of stable microtubules suggests that acetylation and possibly detyrosination may play a role in the maintenance of stable populations of microtubules.

Percutaneous endoscopic gastrostomy tube removal and replacement after "buried bumper syndrome": the simple way.

BACKGROUND: Percutaneous endoscopic gastrostomy (PEG) feeding tubes are required for an increasing number of patients with long-term nutritional requirements. "Buried bumper syndrome" (BBS) occurs in 2-6% of PEG placements. In the past, this has been a difficult problem to resolve. The authors aimed to design a safe and simple method of dealing with BBS that can be performed by any endoscopist on a routine endoscopic list with the patient under sedation. METHODS: For 6 years, the authors have used a minimally invasive way to deal with BBS. They have successfully treated 20 BBS patients on a routine endoscopy list with the patient under sedation. The existing PEG is divided 5 cm from the skin. A pair of stent-grasping forceps is inserted via the tube. A snare then is passed via the gastroscope, caught in the stent-grasping forceps, and brought out via the PEG tube. Next, the tube is split as deeply as possible into the PEG exit site, and the snare is closed around the tube. Gentle traction is applied along the endoscope, allowing the internal bumper to concertina and pop through the mucosa. Another PEG can now be placed at a separate site, although the authors have successfully used the same tract. RESULTS: All the patients were followed up, with no further problems related to BBS. CONCLUSIONS: The authors' method is a simple way of addressing the difficult BBS problem. It can be used to remove and replace a PEG with a buried bumper on a routine endoscopy list with the patient under sedation.

Conversion after laparoscopic cholecystectomy in England.

BACKGROUND: Laparoscopic cholecystectomy is the procedure of choice for the treatment of symptomatic gallstones. Conversion to open surgery is reported to be necessary in 5-10% of cases. This study aimed to define those factors associated in English hospitals with the need to convert a laparoscopic cholecystectomy to an open procedure. These included patient-related and particularly nonpatient-related factors. METHODS: Using data derived from a national administrative database, Hospital Episode Statistics, patients undergoing cholecystectomy in acute National Health Service (NHS) hospitals in England during the financial years 2004-2006 were studied. The individual surgeon caseload and the hospital conversion rate were calculated using data from the first (baseline) year. Factors affecting the need for conversion were analyzed using data from the second (index) year. RESULTS: The study included 43,821 laparoscopic cholecystectomies undertaken from 2005 to 2006 in English hospitals. The overall conversion rate was 5.2%: 4.6% for elective procedures and 9.4% for emergency procedures. Patient-related factors that were good predictors of conversion included male sex, emergency admission, old age, and complicated gallstone disease (p < 0.001). Nonpatient-related factors that were good predictors of conversion included the laparoscopic cholecystectomy caseload of individual consultant surgeons and the overall hospital conversion rate in the previous year (all p < 0.001). CONCLUSIONS: Conversion after laparoscopic cholecystectomy is less common as consultant caseload increases. This suggests that operation should be undertaken only by surgeons with an adequate caseload. There is a wide variation in conversion rates among hospitals. This has important implications for training as well as for the organization and accreditation of cholecystectomy services on a national basis.

Management of acute gallbladder disease in England.

BACKGROUND: Recent literature suggests that early laparoscopic cholecystectomy for acute gallbladder disease is safe and efficacious, but few data are available on the management of acute gallbladder disease in England. METHODS: Hospital Episode Statistics data for the years 2003-2005 were obtained from the Department of Health. All patients admitted as an emergency with acute gallbladder disease during the period from April 2003 to March 2004 were included as a cohort. Repeat emergency admissions for acute gallbladder disease, and cholecystectomies performed during the first admission, an emergency readmission or an elective admission were followed up until March 2005. RESULTS: Some 25,743 patients were admitted as an emergency with acute gallbladder disease, of whom 3791 had an emergency cholecystectomy during the first admission (open cholecystectomy (OC) 29.8 per cent, laparoscopic conversion rate (LCR) 10.7 per cent) and 9806 patients had an elective cholecystectomy (OC 11.3 per cent, LCR 8.3 per cent) during the study period. CONCLUSION: Early cholecystectomy for acute gallbladder disease is not widely practised by surgeons in England. Open cholecystectomy is more commonly used in the emergency than in the elective setting. Early laparoscopic cholecystectomy following an emergency admission carries a higher conversion rate than elective cholecystectomy.

Polyadenylation polymorphism in the acetyltransferase 1 gene (NAT1) increases risk of colorectal cancer.

Exposure to carcinogens present in the diet, cigarette smoke, or the environment may be associated with increased risk of colorectal cancer. Aromatic amines (aryl- and heterocyclic) are a class of carcinogens that are important in these exposures. These compounds can be N- or O-acetylated by the NAT1 or NAT2 enzymes, resulting in activation or in some cases detoxification. Recent studies have shown that both NAT2 and NAT1 genes exhibit variation in human populations and that rapid acetylation by the NAT2 enzyme may be a risk factor for colorectal cancer. In this study we have analyzed for genetic polymorphism in both NAT1 and NAT2 in a group of 202 colorectal cancer patients and 112 control subjects from Staffordshire, England. We find significantly increased risk (odds ratio, 1.9; 95% confidence interval, 1.2-3.2; P = 0.009) associated with the NAT1*10 allele of NAT1, an allele that contains a variant polyadenylation signal. Individuals with higher stage tumors (Duke's C) were more likely to inherit this variant allele (odds ratio, 2.5; 95% confidence interval, 1.3-4.7; P = 0.005). In contrast, rapid acetylation genotypes of NAT2 were not a significant risk factor in this English population. However, we found that the risk associated with the NAT1 variant allele (NAT1*10) was most apparent among NAT2 rapid acetylators (odds ratio, 2.8; 95% confidence interval, 1.4-5.7; P = 0.003), suggesting a possible gene-gene interaction between NAT1 and NAT2 (test for interaction; P = 0.12). This is the first study to test for cancer risk associated with the NAT1 gene, and these positive findings suggest that NAT1 alleles may be important genetic determinents of colorectal cancer risk.

Hemiarthroplasty using cemented or uncemented stems of proven design: a comparative study.

National Institute of Clinical Excellence guidelines state that cemented stems with an Orthopaedic Data Evaluation Panel (ODEP) rating of > 3B should be used for hemiarthroplasty when treating an intracapsular fracture of the femoral neck. These recommendations are based on studies in which most, if not all stems, did not hold such a rating. This case-control study compared the outcome of hemiarthroplasty using a cemented (Exeter) or uncemented (Corail) femoral stem. These are the two prostheses most commonly used in hip arthroplasty in the UK. Data were obtained from two centres; most patients had undergone hemiarthroplasty using a cemented Exeter stem (n = 292/412). Patients were matched for all factors that have been shown to influence mortality after an intracapsular fracture of the neck of the femur. Outcome measures included: complications, re-operations and mortality rates at two, seven, 30 and 365 days post-operatively. Comparable outcomes for the two stems were seen. There were more intra-operative complications in the uncemented group (13% vs 0%), but the cemented group had a greater mortality in the early post-operative period (n = 6). There was no overall difference in the rate of re-operation (5%) or death (365 days: 26%) between the two groups at any time post-operatively. This study therefore supports the use of both cemented and uncemented stems of proven design, with an ODEP rating of 10A, in patients with an intracapsular fracture of the neck of the femur.

Phenol sulphotransferase SULT1A1*1 genotype is associated with reduced risk of colorectal cancer.

Sulphation is an important detoxification pathway for numerous xenobiotics; however, it also plays an important role in the metabolism and bioactivation of many dietary and environmental mutagens, including heterocyclic amines implicated in the pathogenesis of colorectal and other cancers. A major sulphotransferase (SULT) enzyme in humans, SULT1A1, is polymorphic with the most common variant allele, SULT1A1*2, occurring at a frequency of about 32% in the Caucasian population. This allele codes for an allozyme with low enzyme activity and stability compared to the wild-type (SULT1A1*1) enzyme, and therefore SULT1A1 genotype may influence susceptibility to mutagenicity following exposure to heterocyclic amines and other environmental toxins. Previously, a significant association of SULT1A1*1 genotype with old age has been observed, suggesting a 'chemoprotective' role for the high-activity phenotype. Here we have compared the frequencies of the most common SULT1A1 alleles in 226 colorectal cancer patients and 293 previously described control patients. We also assessed whether SULT1A1 genotype was related to various clinical parameters in the patient group, including Duke's classification, differentiation, site, nodal involvement and survival. There was no significant difference in allele frequency between the control and cancer patient populations, nor was there a significant association with any of the clinical parameters studied. However, when the age-related difference in allele frequency was considered, a significantly reduced risk of colorectal cancer (odds ratio = 0.47; 95% confidence interval = 0.27-0.83; P = 0.009), was associated with homozygosity for SULT1A1*1 in subjects under the age of 80 years. These results suggest that the high activity SULT1A1*1 allozyme protects against dietary and/or environmental chemicals involved in the pathogenesis of colorectal cancer.

Glutamate acting on NMDA receptors stimulates neurite outgrowth from cerebellar granule cells.

The effect of endogenous glutamate on neurite outgrowth from cerebellar granule cells in culture was examined. Neurite outgrowth was inhibited by enzymatic removal of endogenous glutamate from the culture medium. The broad-spectrum glutamate receptor antagonist kynurenate also inhibited neurite outgrowth from granule cells in serum-containing and serum-free cultures; the inhibition by kynurenate was reversed by exogenous glutamate. Neurite outgrowth was inhibited to the same extent by the NMDA receptor antagonist APV. These results indicate that endogenous glutamate, possibly released by granule cells themselves, stimulated neurite outgrowth through activation of the NMDA class of glutamate receptors. Activation of NMDA receptors on developing neurons may be an important mechanism for the regulation of neuronal growth and differentiation.

Effect of hypothyroidism on the expression of three microtubule-associated proteins (1A, 1B and 2) in developing rat cerebellum.

The microtubule-associated proteins 1A, 1B and 2 are present at high levels in Purkinje cell dendrites of normal adult rat cerebellum but show characteristic changes in localization during cerebellar development that allow examination of the effects of hypothyroidism on the development of both Purkinje cells and granule cells. Neonatal rats were made hypothyroid by treatment with propylthiouracil from the day of birth (post-natal day 0, P0). The expression of the microtubule-associated proteins 1A, 1B and 2 in the cerebellum of hypothyroid animals was examined using immunocytochemical techniques and compared to the normal developmental pattern in control animals. The normal developmental decrease in microtubule-associated protein 1A and 1B levels in parallel fibres was delayed in the cerebellum of hypothyroid animals and these proteins persisted in parallel fibres until after P20. Microtubule-associated protein 1B but not 1A was still present in parallel fibres in less mature folia at P30 in hypothyroid rats suggesting that the expression of these two microtubule-associated proteins is regulated separately. In the molecular layer staining with anti-microtubule-associated protein 2 was enriched in Purkinje cell dendrites in normal and hypothyroid cerebella and the stained Purkinje cell dendrites in hypothyroid cerebellum demonstrated a typical deformed morphology at P15. The results show that the restricted subcellular localization of these microtubule-associated proteins is maintained in the cerebellum of hypothyroid rats but the developmental changes in their expression are delayed.

Expression of amyloid precursor protein in human astrocytes in vitro: isoform-specific increases following heat shock.

The beta-amyloid protein deposited in senile plaques and cerebral blood vessels in the Alzheimer's disease brain is derived from the larger transmembrane spanning amyloid precursor protein. The present study investigates the effects of heat shock on the expression and processing of amyloid precursor protein in a normal human fetal astrocytic cell line CC2565 using reverse transcription-polymerase chain reaction, in situ hybridization histochemistry and western blot analysis. Heat shock led to an increase in the messenger RNA encoding Kunitz protease inhibitor isoforms of amyloid precursor protein, which peaked at 4h post-heat shock. This increase was confined to the messenger RNA encoding amyloid precursor protein-751, with a decrease in amyloid precursor protein-770 and no change in amyloid precursor protein-695. This shift in splicing was accompanied by a significant decrease in secreted amyloid precursor protein and an increase in beta-secretase processing within the cell. These findings demonstrate that astrocytes in vitro demonstrate a striking response to heat shock. This is unlikely to be due to a direct action on the promoter region of the gene, since the response is specific for one splice variant; amyloid precursor protein-751 messenger RNA. This increase in expression is further accompanied by a decrease in secretion of amyloid precursor protein, implying a shift in processing towards an intracellular route, possibly via the actions of the beta-secretase enzyme, which is known to be potentially amyloidogenic. Such a mechanism may contribute to amyloidosis in the intact brain in response to cellular stress, such as head injury.

Histamine H2-receptor antagonists in peptic ulcer disease. Efficacy in healing peptic ulcers.

Duodenal ulcer healing depends on the degree and length of inhibition of gastric secretion and upon the duration of therapy, while gastric ulcer healing is dependent mainly on the duration of therapy. Currently marketed doses of the histamine H2-receptor antagonists heal between 77 and 92% of duodenal ulcers at 4 weeks, and adjuvant treatment to eradicate Helicobacter pylori increases this rate. Once-daily administration is as effective as more frequent dosing regimens and may even result in higher healing rates. Gastric ulcers heal more slowly, but 75 to 88% of ulcers heal after 8 weeks of treatment. While newer more potent acid suppressors such as omeprazole heal ulcers slightly more quickly, the H2-receptor antagonists have an unparalleled safety record of over 15 years. It is unlikely that the prostaglandin analogues can improve on the efficacy of the H2-receptor antagonists with as low an incidence of side effects.

Histamine H2-receptor antagonists in peptic ulcer disease. Evidence for a prophylactic use.

The H2-receptor antagonists have undoubtably been successful in healing primary gastric and duodenal ulcers so there is a tendency to assume that they will be equally successful when used as prophylactic agents. When used to prevent gastroduodenal ulceration induced by nonsteroidal anti-inflammatory agents, they are unsuccessful in protecting against gastric damage, but reduce the incidence of duodenal ulceration. However, their effect on the incidence of serious complications remains unknown. In the prevention of stress ulceration and bleeding in intensive care units there is evidence of a beneficial effect of H2-receptor antagonists, but other agents are also equally effective. In patients who present with haematemesis and melaena, there is little evidence to show that H2-receptor antagonists reduce rates of transfusion or surgical intervention, or decrease mortality.

Developmental regulation of tyrosine kinase substrate p36 (calpactin heavy chain) in rat cerebellum.

The tyrosine kinase substrate p36 (calpactin heavy chain) is a calcium-dependent membrane- and cytoskeletal-binding protein. Using an affinity-purified antiserum raised against the p36 heavy chain from bovine adrenal medulla, we have examined the cellular distribution of p36 in developing and adult cerebellum. From immunoblotting, the level of p36 in cerebellum was found to decline during development. In dissociated cell cultures of P4 cerebellum, all cell types were labeled by anti-p36. In vibratome sections from cerebella of P10 rats, anti-p36 stained Purkinje cell bodies strongly and all other cell types less strongly, with the exception of cells in the external germinal layer, which were unstained. By 18 days postnatally p36 was present at higher levels in Bergmann glia and astrocytes of the white matter. In sections of adult cerebella, anti-p36 staining was restricted to Bergmann glial processes and to the processes of a subclass of astrocytes in the granular layer and the white matter. At no developmental stage was anti-p36 staining detectable in axons or dendrites in vibratome sections. These results suggest that p36 plays a role in some aspect of cellular differentiation common to all cerebellar cell types and may have additional functions in astrocytes of the adult cerebellum.

Pharmacological response to cimetidine and healing of duodenal ulceration: effects of high-dose cimetidine and combination of cimetidine with pirenzepine.

Overnight gastric secretion was studied in 32 patients with acute duodenal ulcers before treatment and whilst taking cimetidine 400 mg b.d. After 6 weeks of treatment with cimetidine 400 mg b.d. 13 patients had healed ulcers, seven patients had healed ulcers but a persistent erosive duodenitis, and 12 patients had persisting ulceration. Inhibition of nocturnal gastric secretion by cimetidine 400 mg b.d. was most profound in patients who healed their ulcers completely; a less profound inhibition of nocturnal gastric secretion was seen in the non-healing and duodenitis groups. In patients with persisting ulcers and poor inhibition of nocturnal gastric secretion by cimetidine, gastric secretion could be suppressed by either cimetidine 400 mg b.d. in combination with pirenzepine 50 mg b.d., or by cimetidine 1600 mg nocte, but suppression of nocturnal gastric secretion was more effective with cimetidine 1600 mg than cimetidine with pirenzepine.

The non-tyrosinated M alpha 4 alpha-tubulin gene product is post-translationally tyrosinated in adult rat cerebellum.

The distributions of the non-tyrosinated M alpha 4 alpha-tubulin gene product and its tyrosinated form M alpha 4 + Y were examined in immunoblots and sections of adult rat brain. In cerebellar sections, M alpha 4 and M alpha 4 + Y immunoreactivities were enriched in neurons, anti-M alpha 4 + Y labeling thus being more restricted in distribution than that of the general alpha-tubulin antibody YL1/2. The results indicate that the M alpha 4 gene product does not constitute the large non-tyrosinatable pool of alpha-tubulin in brain.