PubMed Health⌕ Search

Biomedical subjects

G Slater

Publications and source records attributed to G Slater.

At least 19 recordsLinked to original sources
PubMed2002

The Ensembl genome database project.

The Ensembl (http://www.ensembl.org/) database project provides a bioinformatics framework to organise biology around the sequences of large genomes. It is a comprehensive source of stable automatic annotation of the human genome sequence, with confirmed gene predictions that have been integrated with external data sources, and is available as either an interactive web site or as flat files. It is also an open source software engineering project to develop a portable system able to handle very large genomes and associated requirements from sequence analysis to data storage and visualisation. The Ensembl site is one of the leading sources of human genome sequence annotation and provided much of the analysis for publication by the international human genome project of the draft genome. The Ensembl system is being installed around the world in both companies and academic sites on machines ranging from supercomputers to laptops.

Computational Biology↗
PubMed2001

Beta-hydroxy-beta-methylbutyrate (HMB) supplementation does not affect changes in strength or body composition during resistance training in trained men.

This investigation evaluated the effects of oral beta-hydroxy-beta-methylbutyrate (HMB) supplementation on training responses in resistance-trained male athletes who were randomly administered HMB in standard encapsulation (SH), HMB in time release capsule (TRH), or placebo (P) in a double-blind fashion. Subjects ingested 3 g x day(-1) of HMB or placebo for 6 weeks. Tests were conducted pre-supplementation and following 3 and 6 weeks of supplementation. The testing battery assessed body mass, body composition (using dual energy x-ray absorptiometry), and 3-repetition maximum isoinertial strength, plus biochemical parameters, including markers of muscle damage and muscle protein turnover. While the training and dietary intervention of the investigation resulted in significant strength gains (p < .001) and an increase in total lean mass (p = .01), HMB administration had no influence on these variables. Likewise, biochemical markers of muscle protein turnover and muscle damage were also unaffected by HMB supplementation. The data indicate that 6 weeks of HMB supplementation in either SH or TRH form does not influence changes in strength and body composition in response to resistance training in strength-trained athletes.

Adult↗
PubMed2000

Prevalence and significance of gallbladder abnormalities seen on sonography in intensive care unit patients.

OBJECTIVE: We evaluated sonographic abnormalities of the gallbladder other than acalculous cholecystitis across a broad range of intensive care unit (ICU) patients. SUBJECTS AND METHODS: Fifty-five consecutive patients (age range, 18-94 years old; mean age, 56 years; 33 men, 22 women), who were admitted to the ICU with a variety of diagnoses, underwent sonography of the gallbladder twice a week. Patients with gallbladder calculi were excluded from the study. The gallbladder was examined for the recognized sonographic features of acalculous cholecystitis: gallbladder wall thickening, gallbladder distention, intramural gallbladder lucencies (striated gallbladder wall), pericholecystic fluid, gallbladder sludge, and Murphy's sign. These findings were correlated with clinical and laboratory parameters that are associated with acalculous cholecystitis: fever, WBC, liver function tests, levels of serum bilirubin, mechanical ventilation status, and administration of parenteral nutrition, narcotic analgesics, antibiotics, and pressor agents. RESULTS: Eleven of the 55 patients were found to have gallbladder calculi and were excluded from the study. Thirty-seven (84%) of the remaining 44 patients had at least one sonographic abnormality while in the ICU. Twenty-five (57%) of the 44 patients had as many as three abnormalities found on sonography, and six (14%) of 44 patients had four or five sonographic findings of gallbladder abnormalities while in the ICU. No statistically significant correlation was found among any of these sonographic abnormalities and the clinical and laboratory parameters. CONCLUSION: Gallbladder abnormalities are frequently seen on sonography in ICU patients, even if these patients are not suspected of having acalculous cholecystitis; therefore, sonography appears to be of limited value in diagnosing acalculous cholecystitis in ICU patients.

Adolescent↗
PubMed1999

Models of local behavior of DNA electrophoresis peak parameters.

Many base calling algorithms implicitly or explicitly rely on predictions of local sequence parameters such as amplitude, peak time and peak width. For example, an algorithm may search for the next peak about a predicted peak time formed by adding the mean peak separation to the last position measurement. In this paper, covariance models are presented which characterize the dependence of peak parameters on those of other peaks. Based on experimental measurements, the model features an exponential decay in peak time jitter covariance with respect to base separation. Both peak amplitude and peak width are modelled as being uncorrelated with those of adjacent bases. In the model, linear expressions are given to describe the growth in peak time jitter and peak width as a function of base position while other parameters, such as amplitude variance, are modeled by constants. Together, these results form a simple model which may be used in the derivation of new sequencing algorithms or in simulations for the testing of such algorithms. We suggest that the correlation of the peak times is related to the Kuhn length of the single-stranded DNA fragments.

Algorithms↗
PubMed1998

GLUT1 glucose transporter expression in colorectal carcinoma: a marker for poor prognosis.

BACKGROUND: Malignant cells exhibit increased glycolytic metabolism, and in many cases increased glucose transporter gene expression. The authors hypothesized that GLUT1 glucose transporter expression is increased in colorectal carcinoma, and that the degree of expression might have prognostic significance. METHODS: GLUT1 glucose transporter immunostaining was studied in normal colon and benign colon adenomas and in 112 colorectal carcinomas from patients for whom long term clinical outcome was known. RESULTS: GLUT1 immunostaining was absent in normal colorectal epithelium and tubular adenomas, and absent or only weakly apparent in tubulovillous adenomas. The majority of carcinomas (101 of 112; 90%) had GLUT1 immunostaining. Tumors from 92 patients had low GLUT1 expression (< 50% of cells were GLUT1 positive) and 19 of these patients (21%) died of disease during follow-up. In contrast, tumors from 20 patients had high GLUT1 expression (> 50% of cells were GLUT1 positive) and 9 of these patients (45%) died of disease during follow-up. Disease specific mortality was greater in patients with high GLUT1 tumors (relative risk of 2.4; P=0.02). In a multivariate analysis to assess whether high GLUT1 staining correlated with increased mortality independently of Dukes stage, the risk of death from colon carcinoma in the group with high GLUT1 staining was 2.3 times that in the group with low GLUT1 staining, a difference that approached statistical significance (P=0.07). CONCLUSIONS: GLUT1 glucose transporter expression is associated strongly with neoplastic progression in the colon, and assessment of the extent of GLUT1 immunostaining in colorectal carcinoma identifies patients with a poorer prognosis.

Adenoma↗
PubMed1996

Mesenteric fibromatosis in Crohn's disease.

We have seen two patients with Crohn's disease and mesenteric fibromatosis, the least common form of desmoid tumor. Although both gastrointestinal and nongastrointestinal tumors are relatively common in Crohn's disease, this type of tumor has not been seen in > 1,650 patients operated on for this condition. As the only common factor in the two male patients discussed in this article was previous intestinal resections, surgical trauma may be a predisposing factor in the occurrence of these desmoid tumors. We will continue to search for other examples in patients with Crohn's disease.

Adult↗
PubMed1996

MR contrast material for vascular enhancement: value of superparamagnetic iron oxide.

OBJECTIVE: The purpose of this study were to quantify abdominal vascular enhancement and to prove the feasibility of iron oxide-enhanced MR angiography in humans using three doses of superparamagnetic iron oxide agent AMI 227. SUBJECTS AND METHODS: Sixteen patients randomly received either 0.8, 1.1, or 1.7 mg Fe/kg of ultrasmall superparamagnetic iron oxide agent AMI 227. T1-weighted breath-hold gradient-echo images were obtained before and 45 min after i.v. administration of AMI 227. Signal intensity was measured in the aorta, the inferior vena cava, the portal vein, and muscle on unenhanced and contrast-enhanced images. Signal-to-noise ratios and enhancement [(SNR after contrast-SNR before contrast) / SNR before contrast] were calculated. Vessels were visually graded before and after administration of AMI 227. RESULTS: All vessels showed statistically significant enhancement 45 min. after administration of AMI 227 by both qualitative and quantitative measures (p < .001). There was no significant increase in noise or signal intensity of muscle after contrast material was administered. The amount of enhancement was not statistically significantly different among the three doses. CONCLUSIONS: AMI 227, which is currently in phase III clinical trials, demonstrates significant vascular enhancement and may prove useful as an MR angiographic contrast agent.

Adult↗
PubMed1994

Capital planning: investing in excellence.

Graham Slater and Kate Del Bravo describe the priorities considered and work undertaken by SETRHA to develop its capital investment strategy. Although the underlying concepts are straightforward, it represents a significant development beyond traditional NHS approaches to planning, embraces the NHS market reforms, and has reduced capital aspirations for the same service objectives by some 300m pounds.

Capital Financing↗
PubMed1993

Clinicopathologic correlations of ABO and Rhesus blood type in colorectal cancer.

There is no specific association established between colorectal cancer and blood group type. In this study, the distribution of ABO and Rh blood groups was studied in 838 patients with colorectal cancer. There was no difference in distribution of ABO blood groups between patients who were Rh+ and Rh-. There was no difference in ABO blood group or Rh factor and tumor location. The highest A/O ratio was found in rectal cancer. Although there was no difference in stage distribution for each ABO blood group, there was a significant difference between the Rh+ and Rh- groups (P < 0.037). It is not clear, however, whether the prognosis is different between the two groups since there were more early tumors as well as incurable tumors in the Rh- group. All patients with synchronous cancer were Rh+. Further studies on blood group antigens are needed to elucidate the relationship between these antigens and colorectal cancer.

ABO Blood-Group System↗
PubMed1993

Management of chondrosarcoma including modular ceramic and alumina prosthetic replacement.

Forty-one cases of chondrosarcoma from varying sites throughout the body, and treated exclusively by one of the authors (R.L.H.) from 1972 to 1990 were reviewed. The symptoms, signs, location of tumours, treatment and progress are presented. Particular attention was paid to modular bone replacement techniques. Excision and reconstruction of the bone or joint were carried out in 17 femora, five tibia and six humeri. Comparison between this method of management and other techniques is discussed. Titanium and alumina prostheses for the hip, femur, tibia, shoulder and humerus have been designed by the senior author. These are both inert and modular, and have been found to be superior to other methods of treatment in both function and cosmesis. They do not possess the same potential donor infection risks and other disadvantages of allograft replacement. Immediate postoperative weight bearing and mobilization are possible with these systems. The Huckstep prostheses allow for bony ingrowth into their porous coated alumina sleeves, spacers and stems. In addition, the titanium alloy locking component for the femoral stems has an elasticity half that of other metal alloys and this was found to minimize stress shielding.

Adult↗
PubMed1991

Small bowel length in Crohn's disease.

The length of the small intestine in patients with Crohn's disease who are referred for surgery has not been well studied. In this report, 25 patients with Crohn's disease who were being operated on for the first time had their small intestine measured at the time of surgery. The mean length of small intestine in this group was 501 cm, which was not different from a group of patients without Crohn's disease who were being operated on for other problems. In the group of patients with Crohn's disease, as well as the entire group, there was a correlation between increasing height and longer small bowel length. No other parameters investigated, including weight, surface area, age, sex, and duration of disease, correlated with bowel length. The results of this study are somewhat encouraging to patients with Crohn's disease, since these patients do not start off with a shortened bowel prior to surgery.

Adolescent↗
PubMed1990

Synchronous carcinoma of the colon and rectum.

Reports on the incidence of synchronous carcinoma of the colon and rectum have varied from 2 to 11 per cent. The variability is a result of a lack of uniformity in criteria of diagnosis, differences in the population studied and differences in time period used. In this study, we evaluated the incidence and distribution of synchronous lesions during a recent time period before the use of colonoscopy became widespread. We reviewed the records of all patients with newly diagnosed adenocarcinoma of the colon and rectum who were operated upon at our institution between 1976 and 1981. In a total group of 1,000 patients of which 52 per cent were men, there were 54 patients or 5.4 per cent who had synchronous carcinomas. The group of patients with synchronous carcinomas were older than the group with nonsynchronous carcinomas (72.4 versus 68.8 years). There was also a higher incidence of associated benign polyps in the group with synchronous carcinomas (70 versus 30 per cent for a nonsynchronous carcinomas). The anatomic distribution of carcinomas of the colon and rectum in the group with synchronous lesions (111 in total) revealed a higher percentage of carcinomas located on the right side (29.7 versus 22.5 per cent), although the difference did not reach statistical significance. Synchronous carcinomas were located in nonadjacent segments of the colon in 37 per cent. There was no difference in stage between the groups with and without synchronous carcinomas. The preoperative identification of synchronous lesions by either colonoscopy or barium enema is important for the proper treatment of patients with carcinoma of the colon and rectum. Failure to locate these tumors may lead to the demise of the patient.

Adenocarcinoma↗
PubMed1989

Age and sex distribution of patients with colorectal cancer.

A retrospective review of 922 colorectal cancer patients was undertaken to determine whether the nonuniform anatomic distribution of colorectal cancer was influenced by age and/or sex. The mean age of patients with right colon lesions (71.2 years) was significantly higher than for either patients with left colon lesions (68.2 years) or rectal lesions (65.6 years). Further analysis disclosed that patients with proximal tumors were older than patients with distal tumors primarily because of the later presentation of females with cecal or ascending colon cancers. Comparison of the anatomic distribution of tumors in patient groups above and below the age of 70 revealed that right colon cancers accounted for a greater percentage of colorectal tumors in the older patient group than in the younger patient group. These findings support the roles played by both age and sex in influencing colorectal cancer location. Furthermore, these data provide a plausible explanation for the increasing incidence of proximal colonic lesions.

Adenocarcinoma↗
PubMed1989

Gastric fistulas in Crohn's disease. Report of cases.

Nine cases of gastric fistula occurring in patients with Crohn's disease were treated at The Mount Sinai Hospital over the past three decades. Six cases were found in a review of 1480 patients with Crohn's disease admitted between 1960 and 1983. Three others seen at this institution outside the time frame of the author's study have also been included. Among six new cases, five with cologastric fistula occurred among 907 patients with Crohn's disease involving the colon (0.6 percent), while only one with ileogastric fistula was encountered among 1211 patients with ileal disease (0.08 percent). Fistulas between the stomach and colon always originated in an area of colitis, usually passing from distal transverse colon to greater curvature, but occasionally from midtransverse colon to antrum. The only pathognomonic clinical features were feculent vomiting, eructations, or odor. Diagnosis usually was made by barium enema or, less frequently, by upper gastrointestinal series; rarely, the gastric fistula was found unexpectedly at surgery. The conventional and recommended therapy is colectomy with wedge excision of the stomach. Medical treatment with 6-mercaptopurine has been completely successful in one patient and intermittently successful in a second patient.

Adult↗
PubMed1989

In vivo formation of hydroxyl radicals following intragastric administration of ferrous salt in rats.

Accidental poisoning by oral iron preparations is a serious problem in young children. We investigated the formation of hydroxyl radicals (.OH) in rats after intragastric instillation of ferrous sulfate. .OH was detected via its reaction with intragastrically administered 2-keto-4-methylthiobutyrate to generate ethylene gas. Ascorbic acid is typically present in oral iron preparations in order to facilitate absorption by maintaining iron in the reduced state. However, ascorbate possesses two properties that can affect .OH, recycling of oxidized iron to the ferrous state augments .OH production, while ascorbate in high concentration scavenges .OH. In experiments conducted in vitro, both actions were evident, depending upon the concentration of ascorbate. In parallel experiments conducted in vivo, the scavenging action of ascorbate was more prominent. Experiments in vitro with .OH-scavengers (dimethylsulfoxide, ethanol) and with the enzyme, catalase, confirmed both the presence of .OH and its dependence upon generated hydrogen peroxide during the oxidation of ferrous salt by molecular oxygen. Hydroxyl radicals (and/or reactive higher oxidation states of iron) may play a role in tissue damage after accidental overdose of oral iron.

Administration, Oral↗