Search PubMed⌕ Search

Biomedical subjects

M Shelton

Publications and source records attributed to M Shelton.

42 records · Page 3Linked to original sources
PubMedDate not supplied

Studies on tail length of Rambouillet and Mouflon sheep.

Data are presented on tail length of various breeds or crosses of sheep and various combinations of Mouflon X Rambouillet breeding. Mouflons sheep had 11 coccygeal vertebrae, and Rambouillet had 18-24. Others were intermediate between these types. Finewool sheep (Merino or Rambouillet) had longer tails than medium wool (Dorset, Suffolk or Hampshire), crossed, or Rambouillet breeds. Heritability estimates for tail length of Rambouillet were 0.387 (intra-sire regression), 0.344 (half-sib method), and 0.706 for inter se matings in a population containing some Mouflon breeding. In the Rambouillet breed, tail length was shown to be correlated with various measures of wool production. However, this relationship was low and only wool covering and staple length were significant. The significance of this to the development of long tails in animals under domestication is discussed.

Animals↗
PubMedDate not supplied

Neuronal ceroid lipofuscinosis in Rambouillet sheep: characterization of the clinical disease.

A chronic progressive, neurodegenerative disease has been identified in 4 closely related flocks of purebred Rambouillet sheep. Blindness, circling, proprioceptive deficits, reduced cognition, and poor body condition are the main clinical signs. Prominent lesions include markedly decreased cerebral size and weight, enlarged cerebral ventricles, and intraneuronal accumulations of autofluorescent pigment. Affected sheep usually die between 1 and 2 years of age. The clinical signs and postmortem findings are consistent with neuronal ceroid-lipofuscinosis.

Animals↗
PubMedDate not supplied

Zidovudine pharmacokinetics in HIV-positive women during different phases of the menstrual cycle.

STUDY OBJECTIVE: To examine the pharmacokinetics of zidovudine during the menstrual cycle in human immunodeficiency virus- (HIV-) positive women. DESIGN: Open, unblinded study. SETTING: A women's clinic for acquired immunodeficiency syndrome (AIDS) at a large medical center. PATIENTS: HIV-positive women with a CD4+ cell count above 200/mm3, receiving long-term zidovudine therapy, with a history of regular menstrual cycles. INTERVENTIONS: All patients received a 100-mg dose of zidovudine in the fasted state on three occasions. MEASUREMENTS AND MAIN RESULTS: Zidovudine and zidovudine-glucuronide plasma concentrations were measured with radioimmunoassay to determine the pharmacokinetic characteristics during each menstrual phase. The drug's mean peak plasma concentrations (range 233-808 ng/ml) were 556 +/- 145, 385 +/- 132, and 495 +/- 143 ng/ml during the menstrual, late follicular-ovulatory, and luteal phases, respectively. Initially, plasma concentrations declined in a linear fashion from 0 to 4 hours, with a prolonged elimination phase in many patients after 4 hours. The mean zidovudine area under the curve was 886 +/- 156, 845 +/- 268, and 775 +/- 167 ng.hour/ml. The mean percentage of dose recovered was 44.2 +/- 26.0, 56.9 +/- 19.1, and 42.2 +/- 16.6, respectively. CONCLUSIONS: The pharmacokinetics of zidovudine were not different during the three phases of the menstrual cycle; however, considerable intrapatient and interpatient variability was noted for many of the values.

Adult↗
PubMedDate not supplied

Comparison of measured and estimated creatinine clearance in patients with advanced HIV disease.

STUDY OBJECTIVE: To assess the accuracy of five creatinine clearance equations in predicting measured creatinine clearance in hospitalized patients with human immunodeficiency viral (HIV) infection. DESIGN: Prospective evaluation over a 6-month period. SETTING: Erie County Medical Center, a 550-bed teaching institution. PATIENTS: Forty-seven HIV-positive patients (39 men, 8 women) who were admitted for a variety of HIV-related illnesses and judged clinically to have stable renal function. Of the 47 original patients, 44 were evaluable based on exclusion criteria. INTERVENTIONS: Serum creatinine and 24-hour measured creatinine clearance were performed in each patient. MEASUREMENTS AND MAIN RESULTS: The estimated creatinine clearance from each of the equations (Cockcroft-Gault, two Jeliffe equations, Mawer et al, and Hull et al) was compared with the measured creatinine clearance. Statistical analysis of these comparisons was performed and all of the equations were found to overestimate the measured creatinine clearance (mean error 34-45%). CONCLUSIONS: Many HIV-infected patients have a decreased creatinine clearance despite a serum creatinine concentration within the normal range. Each of the equations overestimated the measured creatinine clearance.

Adult↗