Search PubMed⌕ Search

Biomedical subjects

M J Shaw

Publications and source records attributed to M J Shaw.

At least 19 recordsLinked to original sources
PubMed1999

Same-day discharge after endoscopic biliary sphincterotomy: observations from a prospective multicenter complication study. The Multicenter Endoscopic Sphincterotomy (MESH) Study Group.

BACKGROUND: Same-day discharge after endoscopic biliary sphincterotomy (ES) is a common clinical practice, but there have been few data to guide appropriate selection of patients. Using a prospective, multicenter database of complications, we examined outcomes after same-day discharge as it was practiced by a variety of endoscopists and evaluated the ability of a multivariate risk factor analysis to predict which patients would require readmission for complications. METHODS: A 150-variable database was prospectively collected at time of ES, before discharge and again at 30 days in consecutive patients undergoing ES at 17 centers. Complications were defined by consensus criteria and included all specific adverse events directly or indirectly related to ES requiring more than 1 night of hospitalization. RESULTS: Six hundred fourteen (26%) of 2347 patients undergoing ES were discharged on the same day as the procedure, ranging from none at 6 centers to about 50% at 2 centers. After initial observation and release, readmission to the hospital for complications occurred in 35 (5.7%) of 614 same-day discharge patients (20 pancreatitis and 15 other complications, 3 severe). Of the same-day discharge patients, readmission was required for 14 (12.2%) of 115 who had at least one independently significant multivariate risk factor for overall complications (suspected sphincter of Oddi dysfunction, cirrhosis, difficult bile duct cannulation, precut sphincterotomy, or combined percutaneous-endoscopic procedure) versus 21 (4.2%) of 499 without a risk factor (odds ratio 3.1: 95% confidence interval [1.6, 6.3], p < 0.001). Of complications presenting within 24 hours after ES, only 44% presented within the first 2 hours, but 79% presented within 6 hours. CONCLUSIONS: Same-day discharge is widely utilized and relatively safe but results in a significant number of readmissions for complications. For patients at higher risk of complications, as indicated by the presence of at least one of five independent predictors, observation for 6 hours or overnight may reduce the need for readmission.

Adult↗
PubMed1996

Complications of endoscopic biliary sphincterotomy.

BACKGROUND: Endoscopic sphincterotomy is commonly used to remove bile-duct stones and to treat other problems. We prospectively investigated risk factors for complications of this procedure and their outcomes. METHODS: We studied complications that occurred within 30 days of endoscopic biliary sphincterotomy in consecutive patients treated at 17 institutions in the United States and Canada from 1992 through 1994. RESULTS: Of 2347 patients, 229 (9.8 percent) had a complication, including pancreatitis in 127 (5.4 percent) and hemorrhage in 48 (2.0 Percent). There were 55 deaths from all causes within 30 days; death was directly or indirectly related to the procedure in 10 cases. Of five significant risk factors for complications identified in a multivariate analysis, two were characteristics of the patients (suspected dysfunction of the sphincter of Oddi as an indication for the procedure and the presence of cirrhosis) and three were related to the endoscopic technique (difficulty in cannulating the bile duct achievement of access to the bile duct by "precut" sphincterotomy, and use of a combined percutaneous-endoscopic procedure). The overall risk of complications was not related to the patient's age, the number of coexisting illnesses, or the diameter of the bile duct. The rate of complications was highest when the indication for the procedure was suspected dysfunction of the sphincter of Oddi (21.7 percent) and lowest when the indication was removal of bile-duct stones within 30 days of laparoscopic cholecystectomy (4.9 percent). As compared with those who performed fewer procedures, endoscopists who performed more than one sphincterotomy per week had lower rates of all complications (8.4 percent vs. 11.1 percent, P=0.03) and severe complications (0.9 percent vs. 2.3 percent, P=0.01). CONCLUSIONS: The rate of complications after endoscopic biliary sphincterotomy can vary widely in different circumstances and is primarily related to the indication for the procedure and to endoscopic technique, rather than to the age or general medical condition of the patients.

Age Factors↗
PubMed1995

Isolation of Arabidopsis mutants altered in the light-regulation of chalcone synthase gene expression using a transgenic screening approach.

Transgenic Arabidopsis expressing beta-glucuronidase (GUS) driven by a chalcone synthase gene (CHS) promoter were produced. GUS activity in the leaves increased with increasing fluence rates of white light in parallel with endogenous CHS transcript levels. An isogenic line homozygous for the transgene was obtained and mutagenized seedlings of this line were screened for altered light-induction of the transgene. Putative mutants with low GUS activity were not altered in the light-induction of endogenous CHS transcripts and are therefore not regulatory mutants. Two mutant lines (A12 and C10) with elevated levels of GUS activity in the light show a corresponding increase in CHS transcript levels. The A12 mutant was focussed upon and designated icx1 (increased chalcone synthase expression). This mutant has enhanced light-stimulation of CHS expression since CHS transcript levels in darkness in icx1 are very low, as in the wild-type. The transcript levels of two other genes involved in flavonoid biosynthesis are elevated in the light in icx1 as is anthocyanin formation. However, there is no alteration in LHCII chlorophyll a/b-binding protein gene (CAB) transcript levels under the same conditions. The altered gene expression phenotype of icx1 co-segregates with several other phenotypic characteristics, including fewer leaf trichomes and alterations to the seed coat. On the basis of these data and comparison with the Arabidopsis ttg (transparent testa glabra) mutant, it is suggested that the ICX1 gene product may be concerned both with the light-regulation of gene expression and with developmental processes occurring in the epidermis.

Acyltransferases↗
PubMed1995

Regular formoterol treatment in mild asthma. Effect on bronchial responsiveness during and after treatment.

Regular beta 2-adrenoceptor agonist therapy may lead to a rebound increase in bronchial responsiveness on discontinuation of therapy and a reduction in bronchoprotective effects. Formoterol, a long-acting beta 2-agonist, is effective in single doses in the prevention of methacholine-induced bronchoconstriction. In a double-blind, placebo-controlled cross-over study, we examined the effect of an inhaled long-acting beta 2-adrenoceptor agonist, formoterol (24 micrograms twice a day) for 2 wk on airway function and responsiveness in 17 subjects with mild asthma (mean age, 26.3 +/- 1.4 yr) who were not taking inhaled glucocorticosteroids. FEV1 and the provocative concentration of methacholine causing a 20% fall in FEV1 (PC20) were measured at 36, 60, and 108 h and at 2 wk after the last dose of regular treatment. In addition, PC20 was measured 12 h after the first and the last dose of formoterol and placebo. PC20 values at 36, 60, and 108 h and at 2 wk after formoterol treatment cessation were not significantly different from those after placebo. Mean FEV1 was 3.44 +/- 0.18 L after placebo compared with 3.79 +/- 0.20 L after formoterol (p < 0.001) 12 h after the first dose, and mean PC20 was 0.53 (GSEM 1.4) mg/ml after placebo compared with 2.0 (GSEM 1.4) mg/ml after formoterol (p < 0.001). After 2 wk of regular treatment, mean FEV1 at 12 h after the final dose of formoterol fell to 3.51 +/- 0.23 L compared with 3.41 +/- 0.18 L after the final dose of placebo (p = 0.03).(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic beta-Agonists↗
PubMed1994

Audit in restorative dentistry.

Auditing activity requires patient data to be collected and analysed to allow comparisons to be made and conclusions drawn. Within the General Dental Services the Dental Practice Board regularly collects practitioner specific clinical data and distributes this to allow dentists to compare their own clinical activity with local and national means. In hospital dentistry, a software package has been developed to enable orthodontic audit to be performed in hospital practice. The package is now being piloted in several centres. A similar software package is required for auditing restorative dentistry activity in units where consultant services are provided. Hospital patient administration systems provide demographic data and appointment systems predominantly with little opportunity for patient specific clinical analysis. Carefully designed software will allow appropriate clinical data and analysis. To ensure compliance and accurate recording both by clinical and support staff it is essential that any software system should be easy to use.

Dental Service, Hospital↗
PubMed1993

Current management of symptomatic gallstones.

Present medical alternatives for the treatment of symptomatic cholelithiasis have been shown to be safe but of limited efficacy. The only medical option approved by the Food and Drug Administration is dissolution with an oral agent. This therapy is appropriate for patients with mild or infrequent symptoms who are poor operative risks or have a low risk of recurrence (ie, long-term users of nonsteroidal anti-inflammatory agents or those who have single stones). Now and for the foreseeable future, laparoscopic cholecystectomy is the procedure of choice for treatment of symptomatic cholelithiasis.

Chenodeoxycholic Acid↗
PubMed1993

Principles of nutrition therapy for short-bowel syndrome.

Short-bowel syndrome is characterized by maldigestion, malabsorption, dehydration, electrolyte abnormalities, and both macronutrient and micronutrient deficiencies. Nutritional and hydration status are difficult to maintain without the provision of specialized nutrition support when more than 75% of the small intestine has been resected. Each patient's response to small-bowel resection is unique; therefore, the type of therapy must be tailored to each individual's bowel resection, complications that ensue, and specific nutrient needs. Clinical management should be guided by principles of nutrition assessment and treatment of nutrient deficiencies as well as routine monitoring of the patient's clinical course and response to therapy.

Adult↗
PubMed1993

Cystic duct anatomy: an endoscopic perspective.

Knowledge of the junction of the cystic and common hepatic duct is essential for endoscopic management of biliary tract disease. The cystic and common hepatic ducts were evaluated retrospectively in cholangiograms obtained for a variety of indications in 524 persons. The cysticohepatic junction was adequately visualized in 70%. Medial junctions were noted in 18% and a spiral configuration in 32%, both more common than reported. An 11% occurrence of parallel duct systems was less frequent than expected. In 10% of patients, the cystic duct entered the hepatic duct in the distal third of the extrahepatic biliary tree. The importance of understanding this anatomy is illustrated with selected cases of therapeutic biliary endoscopy and laparoscopic cholecystectomy complications. Suggestions are made for improving performance in this area.

Adult↗
PubMed1993

Results of a multicenter trial using a mechanical lithotripter for the treatment of large bile duct stones.

A prospective, uncontrolled trial of the use of a prototype mechanical lithotripter was performed in 116 patients at nine centers. Standard endoscopic approaches had failed to remove all stones, primarily because of large size (80% of patients). For 92% of patients, common bile duct stones were successfully captured and fragmented following the use of this lithotripter. The frequency of pancreatitis and hemorrhage was no greater than with standard endoscopic retrograde sphincterotomy, and complications unique to lithotripter use were not noted. For endoscopists skilled in therapeutic duodenoscopy, this modality should be considered in management of common bile duct stones refractory to standard techniques.

Equipment Design↗
PubMed1991

The effectiveness of differing dental health education programmes in improving the oral health of adults with mental handicaps attending Birmingham adult training centres.

There are few published data available relating to dental health in adults with handicaps, or to the effectiveness of dental health education in this group. The present study involved 382 people attending four different adult training centres in Birmingham, UK. Following baseline examinations all participants were given oral hygiene instruction and a scale and polish. Each of the centres was then randomly allocated to one of the four treatment regimens. No specific treatment was provided for the control group; daily supervised toothbrushing was carried out by the participants in the other three groups, with the addition of a three-monthly scale and polish and reinforcement of oral hygiene instruction in group 3 and one-monthly input in group 4. The participants were re-examined after three months and then at six-monthly intervals until 24 months after the baseline examination. The results showed that those people left to their own devices to carry out toothbrushing at home following instruction were not achieving an acceptable standard. Those who were reminded, encouraged and motivated by the adult training centre staff were obviously capable of better standards of oral care. The input of an experienced dental hygienist on a regular basis improved the periodontal condition considerably. Although there were significant differences between the groups throughout the study, particularly in the presence of calculus, the differences between the one-monthly and three-monthly hygienist input were not clinically very apparent after two years, and therefore a one-monthly input would be difficult to justify on a cost benefit basis.

Adult↗
PubMed1990

A new mechanical lithotripter for the treatment of large common bile duct stones.

A prospective uncontrolled multi-center trial of a prototype mechanical lithotripter was performed in 30 patients with common bile duct calculi. Standard endoscopic sphincterotomy had failed to remove all stones, primarily because of large size (26 patients). Stone size ranged from 13 to 35 mm. Forty-three of 45 stones (97%) were successfully captured, fragmented, and extracted with this newly designed mechanical lithotripter. The overall success rate of 93% using this simple and inexpensive modality compares favorably with other methods under investigation for the treatment of common bile duct stones not amenable to routine endoscopic measures.

Duodenoscopy↗
PubMed1990

The oral health in different groups of adults with mental handicaps attending Birmingham (UK) adult training centres.

The policies of normalisation and integration into the community of people with mental handicap have significant implications for dental care. Before dental services can be planned, the extent of the problem needs to be identified. A total of 382 people with mental handicap living in the community and attending day centres was examined; 52 of these people were edentulous. The mean age of the dentate adults was 30.9 years and the mean DMFT was 9.59. This was low in comparison with data available from national studies but when component parts of the DMF were evaluated it was apparent that far less restorative care had been received by the adults with mental handicap. There were also significant differences in the mean DMFT between mentally handicapped people who had additional handicaps; the mean DMFT for people with Down's syndrome was 10.95, whilst those mentally handicapped people who also had epilepsy had a mean DMFT of 11.19. The oral hygiene and periodontal condition was also poor and there were significant differences between the sub-groups. However, despite people with Down's syndrome having lower levels of plaque, they showed evidence of greater periodontal destruction. When resources are allocated, consideration should be given to raising the oral health of adults with mental handicap up to at least the same level as that of the rest of the population.

Adult↗
PubMed1989

Correlation of manual dexterity and comprehension with oral hygiene and periodontal status in mentally handicapped adults.

Although there is relatively little information concerning the oral health of handicapped adults there is increasing evidence to suggest that their oral condition, particularly periodontal health, is poor. The present investigation involved assessment of 382 handicapped patients attending four different Adult Training Centres in Birmingham. The caries status, oral hygiene, and periodontal conditions were evaluated and the Community Periodontal Index of Treatment Need (CPITN) was calculated. In order to assess the manual dexterity and the comprehension of the trainees a standard test was devised. This consisted of timing each participant in carrying out simple instructions to pick up and position certain common objects. The results indicated high levels of plaque, calculus, and bleeding with a mean CPITN of 7.43. The mean time taken for the manual dexterity and comprehension test was 23.9 seconds with a range from 10 to 80 seconds, S.E.+/- 1.33. This compares with results from 34 "normal" adults of a mean time of 8.2 seconds +/- 1.8 with a range of 6 to 12 seconds. There was no significant correlation between the Manual Dexterity and Comprehension scores and the periodontal indices in the handicapped adults.

Adult↗
PubMed1988

Bovine gallbladder muscularis: source of a myogenic receptor for cholecystokinin.

Despite being a classic target for the gastrointestinal peptide hormone, cholecystokinin (CCK), the gallbladder CCK receptor is not well characterized. Pharmacological studies of small species suggest that CCK action can be mediated by direct myogenic or by both myogenic and neurogenic receptors. To prepare for the biochemical characterization of a gallbladder CCK receptor and to define the subtype of the receptor being studied, we have performed autoradiographic localization and pharmacological characterization of CCK receptors on bovine gallbladder. Autoradiography demonstrated high-affinity specific CCK-binding sites only on the muscularis. CCK-8 stimulated tonic contraction of longitudinal strips of gallbladder muscularis in a concentration-dependent manner, with an ED50 of 0.2 nM. Antagonism at the cholinergic receptor with 1 microM atropine or axonal transmission with 1 microM tetrodotoxin did not modify CCK-induced contraction, supporting a direct myogenic effect of this hormone. Optimal electrical field stimulation (10 V, 10 Hz, 500 microseconds) to elicit a neuronal response resulted in muscle strip relaxation, which was abolished with adrenergic blockade (1 microM phentolamine, 1 microM propranolol). Although acetylcholine administration stimulated contraction, electrical field stimulation did not, even in the presence of phentolamine, propranolol, and/or CCK. Thus, in bovine gallbladder muscularis, there is evidence for a functional CCK receptor only on smooth muscle cells. Demonstration of a single, high-affinity specific CCK-binding site on an enriched plasma membrane preparation of bovine gallbladder muscularis is consistent with this representing a myogenic CCK receptor.

Animals↗
PubMed1987

Preparation of enriched plasma membranes from bovine gallbladder muscularis for characterization of cholecystokinin receptors.

A method for the preparation of enriched plasma membranes from bovine gallbladder muscularis was developed, validated, and applied to the characterization of receptors for the gastrointestinal hormone cholecystokinin (CCK) on this target. Binding of radioiodinated CCK ligands to this preparation was rapid, reversible, temperature-dependent, saturable, and specific. Only structurally related peptides inhibited CCK binding, and good correlation existed between relative potencies for binding inhibition and for stimulating gallbladder contraction. Computer analysis of CCK-binding data using a nonlinear model-fitting program best fit a model with a single class of sites, with Kd 756 pm and binding capacity 4.5 +/- 1.3 pmol/mg of protein. This degree of enrichment for plasma membranes was adequate for the initial biochemical characterization of this CCK receptor. Affinity labeling using 125I-Bolton Hunter-CCK-33 and m-maleimidobenzoyl-N-hydroxysuccinimide ester identified proteins with Mr = 70,000-85,000, Mr = 120,000-125,000, and Mr = 200,000. Labeling was inhibited in a concentration-dependent manner, with an IC50 of 1 nM CCK-8, and the electrophoretic mobility of these bands was not different under reducing and nonreducing conditions. The major labeled band of Mr = 70,000-85,000 has a lower apparent Mr than that of the analogous band in pancreas labeled with similar methods, supporting the molecular heterogeneity of CCK receptors on these two target tissues.

Animals↗
PubMed1985

Clinical and endoscopic findings in patients early in the course of clostridium difficile-associated pseudomembranous colitis.

Endoscopic and clinical features are reported for 39 patients detected early in the course of pseudomembranous colitis. Disease was detected early by virtue of careful surveillance in patients in whom diarrhea developed. Early proctosigmoidoscopic findings in pseudomembranous colitis are illustrated. Clinical presentation includes development of fever, leukocytosis, abdominal pain, and even an ileus picture on radiography in addition to diarrhea.

Adult↗