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D Knight

Publications and source records attributed to D Knight.

At least 37 records · Page 2Linked to original sources
PubMed1994

Office microbiology.

Explore the source record for details and available documents.

Equipment and Supplies↗
PubMed1993

A comparison of abdominal and vaginal examinations for the diagnosis of engagement of the fetal head.

The diagnosis of engagement of the fetal head is mandatory before operative vaginal delivery is to be attempted. There is widespread belief that the fetal head is engaged in the maternal pelvis when vaginal examination reveals that the bony presenting part has reached the level of the ischial spines. However, it is also claimed that in the presence of moulding the vaginal findings may be misleading and that it may be preferable to make the diagnosis by abdominal examination of the level of the fetal head in relation to the pelvic brim. In order to evaluate the relative merits of each of these 2 systems of physical examination, a retrospective study was made of 104 cases which had been evaluated for possible operative vaginal delivery by both methods. Prediction of successful vaginal delivery was greater by abdominal criteria (94%) than by vaginal criteria (80%) (p < 0.01). When evaluated by maximum likelihood logistic regression analyses, the factor of greatest importance in determining the probability of allocation of a case to each of the engagement groups was moulding (odds ratio 2.17; 95% confidence intervals 0.75-6.27). We conclude that when these 2 methods of assessment produce different diagnoses, the major factor responsible is moulding of the fetal head. Clinical evaluation prior to operative vaginal delivery must include abdominal examination and reliance on vaginal findings alone may prove misleading when moulding is present.

Adult↗
PubMed1992

Indium-111 whole-body retention: a method for quantification of disease activity in inflammatory bowel disease.

Quantification of disease activity in inflammatory bowel disease (IBD) has been by measurement of fecal excretion of 111In-granulocytes. The difficulties of this method prompted us to evaluate quantification of whole-body 111In retention, expressed as a percentage of whole-body activity at 3 hr following injection, as an alternative method. The patient stood in front of the uncollimated gamma camera at a distance of 4 m and counts were collected over 2 min. The geometric mean was taken of posterior and anterior counts and compared with a 111In standard. The lower limit of the 95% confidence interval for whole-body retention in normals was 90%. Forty-five studies were performed on 33 patients with IBD. They were assessed in two groups, one to whom routine instructions for the collection of feces were given (Group A) but who did not always comply. The other group received oral and written instructions and were also monitored during the collection period (Group B) and reported full fecal collection. Although in Group A the correlation between fecal excretion and whole-body retention was good (r = 0.7, n = 32; p less than 0.001), in Group B the relationship between fecal excretion and whole-body retention was significantly better (r = 0.95, n = 18; p less than 0.001). On average, 111In whole-body retention was consistent with findings obtained during imaging: 111In excretion (100-whole-body retention) was 7.8% +/- 4.9% in 5 normal scans, 10% +/- 5.9% in 17 (+) scans, 22.3% +/- 8% in 20 (++) scans and 57% +/- 16% in 8 ( ) scans. We conclude that imaging is more sensitive than whole-body retention and fecal excretion in the detection of disease, but for quantification, whole-body retention is an accurate reliable alternative to fecal excretion.

Adult↗
PubMed1990

Chemical synthesis of dual-radiolabelled cyclandelate and its metabolism in rat hepatocytes and mouse J774 cells.

1. The chemical synthesis of 3,3,5-trimethyl[1-3H]cyclohexanol, 3,3,5-trimethyl[2,3-3H]cyclohexanol and 3,3,5-trimethyl[2,3-3H]cyclohexanyl[1-14C]mandelate (cyclandelate) are described. The ratio of 3H/14C radioactivity in the ester was 27:1. 2. Cultured rat hepatocytes accumulated trimethylcyclohexanol rapidly and excreted its glucuronide into the culture medium. Rat hepatocytes also accumulated cyclandelate rapidly, hydrolysing the ester and excreting trimethylcyclohexanol into the medium. This trimethylcyclohexanol then re-entered the cells and was converted to its glucuronide prior to excretion. 3. In contrast, no hydrolysis of cyclandelate was seen on incubation with J774 cells, a transformed mouse macrophage. 4. Similar differences in hydrolytic activity were seen with microsomal fractions prepared from rat liver and J774 cells. Hepatic microsomes caused a rapid hydrolysis of cyclandelate while no hydrolysis was detectable after incubations of over an hour with J774 microsomes. 5. This difference in hydrolytic activity may have important implications for the action of cyclandelate on cholesterol metabolism in extrahepatic tissues.

Animals↗
PubMed1990

Microcytosis, hypoferremia, hypoferritemia, and hypertransferrinemia in standardbred foals from birth to 4 months of age.

At birth, 24 Standardbred foals were assigned at random to 1 of 2 groups and were given a placebo supplement (group 1) or an iron supplement (248 mg of iron/treatment; group 2). Foals were given iron supplement or placebo 4 times during the second and third weeks after birth. Hematologic variables and general health were monitored until foals were 4 months old. Mean PCV in foals of both groups decreased during the first 2 weeks after birth, but values remained within adult horse reference ranges. During the first 6 weeks after birth, foal erythrocytes were smaller than adult horse erythrocytes, but foal erythrocyte glucose-6-phosphate dehydrogenase activity was greater than that in adult horses. At every measurement, indices of anisocytosis were lower in foals, compared with adult horse reference values, suggesting that foals have a homogeneous population of microcytic erythrocytes during early foalhood. In 2-week-old foals of both groups and in 4-week-old placebo-treated foals, mean serum iron concentration was lower than that in adult horses. In foals at birth and during the first 4 months, total iron-binding capacity values were above the adult reference range. In newborn foals, transferrin saturation percentage values decreased to below the reference range in foals from 2 weeks to 4 months after birth. When foals were born, serum ferritin concentration values were above the adult horse reference range, but decreased to within the reference range by the time foals were 1 day old. From 2 through 6 weeks after birth, foal ferritin concentration values were below the adult reference range.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1989

Colostral and serum IgG, IgA, and IgM concentrations in Standardbred mares and their foals at parturition.

Immunoglobulin G, IgM, and IgA concentrations were measured in serum collected from 36 Standardbred mares within 12 hours of foaling, in colostrum collected within 6 hours of foaling, and in serum collected from foals 24 to 48 hours after birth. In serum collected from mares after parturition, mean concentrations of IgG, IgM, and IgA were 2,463.9 +/- 1,337.3 mg/dl, 136.4 +/- 218 mg/dl, and 305.2 +/- 237.5 mg/dl, respectively. In serum from foals, mean concentrations of IgG, IgM, and IgA were 1,953.3 +/- 1,635 mg/dl, 33.8 +/- 30.4 mg/dl, and 58.4 +/- 42.2 mg/dl, respectively. In colostrum, mean concentrations of IgG, IgM, and IgA were 8,911.9 +/- 6,282.2 mg/dl, 957 +/- 1088.1 mg/dl, and 122.9 +/- 77.3 mg/dl, respectively. The IgG concentrations in foal serum were poorly correlated with IgG concentrations in colostrum (r = 0.462, P less than 0.01). Correlations of IgM or IgA concentrations in serum from foals with IgM or IgA concentrations in colostrum and correlations of IgG concentrations in serum from mares with those in colostrum were not significant (P less than 0.01). Of 36 foals, 1 (2.8%) had a serum IgG concentration less than 400 mg/dl. Of 36 foals monitored for 4 months, 6 developed infectious respiratory tract disease requiring antimicrobial therapy at ages varying from 55 to 113 days; these infections were probably not related to failure or partial failure of passive transfer of antibody.

Animals↗
PubMed1988

Imaging for infection: caution required with the Charcot joint.

Scintigraphic techniques for detecting bone infection can be misleading in neuroarthropathy (Charcot joint). Three patients showed strongly positive three phase bone and 67Ga imaging despite absence of osteitis. Indium labelled white cell imaging provided the correct information on each patient. The findings have important implications for the investigation of diabetic patients with suspected bone infection.

Adult↗
PubMed1988

The effect of firing temperature on the lung retention and translocation of Pu following the inhalation of 238PuO2 and 239PuO2 by CBA/H mice.

Mice were exposed by inhalation to sized aerosols of 238PuO2 and 239PuO2 which had been fired at temperatures from 550-1250 degrees C and groups killed at times between 1 d and 2 y after exposure. Measurements were made of 238Pu and 239Pu in the lungs, lung-associated lymph nodes, liver and skeleton. With 239Pu, lung retention and translocation were independent of firing temperature. With 238Pu on the other hand, the retention in lung was greater initially than for 239Pu but, with the low-fired oxide, eventually fell below that of 239Pu. With high-fired oxides, the lung retention of 238Pu still exceeded that of 239Pu after 2 y. Translocation to liver and bone was invariably greater for 238Pu than for 239Pu and was also dependent on firing temperature. The practical implications of these findings are discussed.

Administration, Inhalation↗