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B J Collins

Publications and source records attributed to B J Collins.

At least 73 records · Page 4Linked to original sources
PubMed1991

Application of molecular encapsulation for toxicology studies: toxicokinetics of p-chloro-alpha,alpha,alpha-trifluorotoluene in alpha-cyclodextrin or corn oil vehicles in male F344 rats.

Toxicokinetics of p-chloro-alpha,alpha,alpha-trifluorotoluene (CTFT) after administration as an aqueous alpha-cyclodextrin (alpha-CD) molecular encapsulation suspension (alpha-CD vehicle) or as a corn oil solution (corn oil vehicle) were compared. Male F344 rats were administered intragastrically CTFT in alpha-CD vehicle or corn oil vehicle at dose levels of 10, 50, or 400 mg/kg. Other male F344 rats were administered CTFT intravenously in a 10% Tween 80 aqueous solution. Serial blood samples were taken from a cannulated jugular vein for up to 52 hr after dosing and the CTFT concentrations in whole blood were determined by gas chromatography. The biological elimination half-life of CTFT from the center compartment was not affected by the vehicle used; however, absorption of CTFT from the alpha-CD vehicle was much faster than from the corn oil vehicle. The average absorption half-lives from the alpha-CD vehicle and corn oil vehicle were 17 and 98 min, respectively. Despite the differences in absorption, no statistical difference was observed in the calculated areas under the blood concentration versus time curves (AUC) obtained from rats dosed with either vehicle. Dose proportionality for CTFT was established up to 400 mg/kg and bioavailability was shown to be complete for both vehicles.

Administration, Oral↗
PubMed1991

How prevalent is cancer family syndrome?

Based on an established but pragmatic definition of cancer family syndrome as the presence of three or more relatives affected by colorectal cancer in a first degree kinship, the contribution of this syndrome to the total cancer burden in Northern Ireland has been studied by investigating all non-polyposis probands under 55 years old at histological diagnosis between 1976 and 1978. Family interviews were possible for 95% (n = 205) of all non-polyposis probands and verification of vital status or medical history was obtained for 98% of 1811 first degree relatives. The prevalence of cancer family syndrome was between 1 and 2%, a figure some fivefold less than that estimated elsewhere. A proximal tumour excess was not characteristic of the ascertained families. These results may have implications for the identification of susceptible people if screening for high risk groups is considered a worthwhile option for reducing colorectal cancer mortality in the United Kingdom.

Colorectal Neoplasms, Hereditary Nonpolyposis↗
PubMed1991

Prognosis in familial non-polyposis colorectal cancer.

Familial cases of non-polyposis colorectal cancer have attracted much interest but little is known of their natural history. Using a population based study we have determined whether a positive family history of bowel cancer is an independent prognostic factor. All patients under 55 years with histologically confirmed colorectal cancer in Northern Ireland during the period 1976-8 were studied. The family history was validated in 95% of all nonpolyposis cases (n = 205). Medical history or cause of death were verified for 98% of 1811 first degree relatives. The strength of the family history was assessed using a score that compares the mortality from bowel cancer in the family against the average population mortality, taking account of family size and age structure. The family history score was not predictive of survival neither in univariate analysis or in a Cox's proportional hazards multivariate analysis controlling for age, sex, stage, site, and duration of symptoms. In conclusion, a positive family history does not independently influence prognosis in patients with bowel cancer.

Cause of Death↗
PubMed1991

A steroid stupor in a surgical ward.

In the development and management of a steroid-induced stupor, in a 17-year-old man, the dose and route of administration of steroid medication were felt to be important aetiological factors. A co-ordinated plan of management involving the physician, surgeon and psychiatrist is needed in such cases.

Adolescent↗
PubMed1991

Histologic characteristics and outcome of familial non-polyposis colorectal carcinoma.

Familial cases of non-polyposis colorectal cancer have recently attracted much interest. Little is known about the characteristic histology or natural history of disease in such cases. Our aim was to determine, through a population-based study, whether mucin-secreting tumours were associated with a positive family history and whether 'familiality' was an independent prognostic variable. All patients under 55 years of age with histologically verified colorectal cancer in Northern Ireland during 1976-78 were studied. The family history was validated in 95% of all non-polyposis cases (n = 205), and the proband's histologic specimen reviewed in over 99%. Mucin-secreting tumours were significantly associated with a positive family history, but familiality was not found predictive of survival in a multivariate analysis controlling for age, sex, stage, site, symptom duration, differentiation, and histologic type.

Adenocarcinoma, Mucinous↗
PubMed1991

Clinical profile in Barrett's esophagus: who should be screened for cancer?

A retrospective survey identified 96 patients (58 males) with Barrett's esophagus, diagnosed at the Royal Melbourne Hospital between 1978 and 1986. The age at presentation varied from 20 to 93 years, and 43% were greater than 70 years. Heartburn was a presenting symptom in 71%, regurgitation into the pharynx in 54%, dysphagia in 31% and hematemesis or melena in 29%. At endoscopy, the length of Barrett's epithelium ranged from 3 cm to 15 cm. Macroscopic esophagitis was observed in 69%, benign esophageal strictures in 14% and a co-existent adenocarcinoma of the lower esophagus in 10% of patients. Only 30% of the patients were cigarette smokers at the time of diagnosis, but 64% drank alcohol (9% greater than 80 g alcohol daily). Patients with esophageal cancer at presentation were more likely to be male and cigarette smokers (Fisher's exact probability test). It has been suggested that patients with Barrett's esophagus should be screened to detect the early development of esophageal cancer. If patients who already have cancer, the elderly (age greater than 70 years) and those with a chronic alcohol problem (greater than 80 g intake daily) are excluded from endoscopic cancer surveillance, only 42% of the patients described in this survey would be eligible for enrollment in such a program. This represents a recruitment of only 5 new patients yearly in a large teaching hospital endoscopy unit.

Adenocarcinoma↗
PubMed1990

Aperistaltic oesophageal disorders unmasked by severe post-fundoplication dysphagia.

Two patients were referred because of persistent dysphagia which developed for the first time after Nissen fundoplication. Investigations, including oesophageal manometry, demonstrated the presence of achalasia in one case, confirmed histologically, and aperistaltic oesophagus associated with an underlying connective tissue disorder in the other case. Our observations highlight the importance of assessing oesophageal motility before referring patients for anti-reflux surgery and illustrate the effect of such surgery on patients in whom oesophageal dysmotility was not suspected.

Connective Tissue Diseases↗
PubMed1990

Biphasic action of forskolin on growth hormone and prolactin secretion by rat anterior pituitary cells in vitro.

To assess the role of cAMP-mediated signal transduction processes in mediation of secretagogue-stimulated GH release, we examined the dose-related effects of the diterpene adenylate cyclase activator forskolin (FSK) in primary monolayer cultures of rat adenohypophyseal cells. In cell cultures prepared from both immature (12 days old) and adult (6 weeks to 4 months old) male or female rats, the dose-related stimulation of GH release by FSK was biphasic. With increasing FSK concentrations from 0.03-3.16 microM, GH release increased progressively to maximal values of 442 +/- 19% and 303 +/- 10% of basal release in cells from immature and adult rats, respectively. FSK concentrations above 3.16 microM induced progressively diminished GH responses, with net inhibition to below basal release evident at 100 microM FSK. FSK stimulated PRL release to a lesser degree than it did GH release; the PRL response to FSK was also biphasic. When maximal stimulatory concentrations (Emax) of FSK and GH-releasing factor (GRF; 10 nM) were added in combination, the GH response was significantly less than the individual response to either secretagogue alone. In response to FSK alone, GRF alone, and FSK plus GRF, GH release was 478 +/- 7%, 583 +/- 11%, and 244 +/- 5%; 278 +/- 4%, 283 +/- 3%, and 175 +/- 2%; and 299 +/- 12%, 351 +/- 5%, and 191 +/- 17% of basal release in cells from 12-day-old, adult male, and adult female rats, respectively (P less than 0.01 for all responses to combined addition vs. the individual responses). Submaximal stimulatory concentrations of GRF added in combination with submaximal FSK elicited partially additive GH responses; the GH response to Emax GRF, on the other hand, was inhibited in a dose-related manner by all concentrations of FSK that by themselves were stimulatory. The GH responses were also suppressed when Emax FSK was added to cultured cells of 12-day-old rats in combination with Emax cholera toxin (2.5 ng/ml) or prostaglandin E2 (10 microM), agents whose actions, like that of GRF, involve adenylate cyclase activation. In contrast, FSK did not suppress but in most cases augmented the maximal GH responses to secretagogues whose action is independent of adenylate cyclase activation: (Bu)2cAMP (0.5 mM), TRH (100 nM), phorbol myristate acetate (50 nM), the Ca2+ ionophore A23187 (250 microM), and the dihydropyridine Ca2+ channel agonist BAY K8644 (10 microM). Indeed, combined addition of FSK with the latter two agents resulted in synergistic stimulation.(ABSTRACT TRUNCATED AT 400 WORDS)

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed1990

Incidence and site distribution of colorectal cancer in Northern Ireland.

Death rates from colorectal cancer in Northern Ireland are higher than in most of the rest of the United Kingdom. Although local surgeons have recognised this problem for some time it has remained unclear whether this reflects a greater underlying incidence or a worse mortality. We have reviewed all histological diagnoses of colorectal cancer in the province over a three year period and we report the incidence and site distribution for this disease in this population of one and a half million. With the exception of rectal cancer in females the incidence of colorectal cancer, whether histologically diagnosed or registered, is higher than in England, Wales or Scotland. The site distribution accords with that in other high risk countries. These results indicate that Northern Ireland has the highest underlying incidence of colorectal cancer in the United Kingdom.

Adult↗
PubMed1989

Assessment of oesophagitis by histology and morphometry.

Morphometric measurements of nuclear area, nuclear concentration and nucleolar dimensions in defined tissue zones of orientated oesophageal biopsy sections were compared between three patient groups--asymptomatic/normal endoscopy (n = 8); symptomatic reflux/normal endoscopy (n = 17); and symptomatic/endoscopic oesophagitis (n = 15). No significant differences could be shown for any mean parameter between clinical groups. In a further group of 16 patients, identical morphometric measurements were made in non-orientated grasp biopsies and correlated with prolonged ambulatory pH data. No significant correlations could be shown between nuclear parameters and acid reflux measurements. These results suggest that morphometric measurement cannot be recommended as a diagnostic tool in the diagnosis of oesophagitis, although it may be useful in the assessment of individual therapeutic response in clinical trials.

Adult↗
PubMed1989

Gastric emptying of oral rehydration solutions in acute cholera.

Gastric emptying of rice powder electrolyte solution and of glucose electrolyte solution was measured by a marker dilution double sampling technique in 14 and in 16 adult patients respectively after intravenous rehydration during an attack of acute cholera. Six patients who received rice powder electrolyte solution and seven who received glucose electrolyte solution re-attended for a repeat study with the same test meal 16 days later, when fully recovered from cholera. No differences in gastric emptying patterns of the two electrolyte solutions were observed, either in the acute or in the recovered patients. Similarly, gastric emptying of both solutions was rapid during acute cholera and comparable to that observed in recovered patients. This study indicates that gastric emptying is not impaired in acute cholera and that the rate of emptying of oral rehydration solutions is adequate to account for their observed clinical efficacy in fast purging patients with acute cholera.

Acute Disease↗
PubMed1988

Loss of Crown Immunity in the NHS; the effect on hotel services.

A less than "holy" combination of the Environmental Officers of Health (EHO) and the pest control industry had for some time been conducting a campaign for the removal of Crown Immunity from hospitals. They had not been so vociferous in their campaign to remove the same privilege from prisons and the armed services. I find it difficult to believe this was out of conviction that other institutions were trouble free. For in 1985 of the 191 Institutional outbreaks only 37 (19%) were in hospitals. The outbreak of Salmonella food poisoning at the Stanley Royd hospital provided enough public pressure to be generated for crown immunity to be removed from NHS premises. It remained in prisons and the armed services.

Accident Prevention↗
PubMed1988

Reassessment of enteric endocrine cell hyperplasia in celiac disease.

Celiac disease is characterized by reversible, gluten-induced, architectural abnormalities of the intestinal mucosa. Villus atrophy is compensated for by an increase in the number of proliferating cells and an increase in crypt cell production rate, resulting in increased crypt length and girth. Several authors, employing various methods of quantitation, have reported enteric endocrine cell hyperplasia in celiac disease. The present study has re-evaluated enteric endocrine cell status in this disorder by employing methods of quantitation which more accurately take account of alterations of crypt morphology than those previously used. Numbers of endocrine cells expressed as cells per unit of crypt length are not increased in the celiac biopsies when contrasted with those from controls. Indeed, numbers of cells immunoreactive for gastrin, GIP, motilin and somatostatin were reduced in the celiac mucosa. Endocrine cell hyperplasia in the celiac small bowel is not as marked as was previously thought, and may lag behind that of the enterocyte population.

Adult↗