Polymorphism of C3 in rabbits.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to M Rose.
Explore the source record for details and available documents.
The characteristics of the hepatic metabolism of Sulfbromophthalein (BSP) have not been described previously for the pig. This is an important deficiency, since the pig is particularly suitable for studies of hepatic physiology and pharmacology which might apply to man. The aim of these experiments was to establish the pattern of serum clearance and biliary excretion of BSP and to determine that dose which would produce a maximal concentration in bile. A dose response and pattern of biliary excretion of BSP was studied at three dose levels administered either as a single bolus of a continuous infusion. All experiments were performed in conscious, conditioned pigs. The patterns of serum clearance and biliary excretion were found to be similar to other laboratory animals and to man. Maximary biliary concentration of BSP was achieved by a single bolus of 5-9 mumol/kg or a constant infusion of 0-59 mumol/kg/min. At these dose levels no significant alteration in bile flow was demonstrated nor was there any correlation between bile flow and BSP excretion. Supra-maximal doses produced a significant increase in bile flow and with these doses there was a significant positive correlation between bile flow and BSP excretion.
The pig is an ideal animal for studies of hepatic metabolism and the handling of drugs by the liver because of the many similarities in liver function to that in man. In this report we describe for the first time, in this animal, methods for the chronic implantation of sampling catheters in the major hepatic vessels and for the construction of an external biliary shunt. This model has many advantages in that it permits in the conscious animal intermittent, simultaneous and precise sampling of the hepatic uptake and clearance of substances and intermittent sampling of bile, without permanent interruption of the enterophepatic circulation. The effectiveness of this preparation has been assessed in 55 pigs. It was demonstrated that the majority of catheters remained patent for at least three days and in many cases for much longer. No significant alteration in liver function could be shown for at least seven days after surgery.
Changes in the cystometric pattern and urethral pressure profile after surgical section of the cauda equina have been studied in a group of 20 monkeys (Macaca nemestrinal). The experimental autonomous bladder was characterised by tonic response to filling and with variable urethral dribbling incontinence but without co-ordinated detrusor activity. This pattern developed despite previous urinary diversion to prevent inadvertent overstretch of the bladder. Deliberate "overstretch" of the autonomous bladder was not followed by loss of tonus but was associated with the development of high amplitude regular detrusor contractions which were superimposed upon a steep rising filling cystometrogram. With urinary diversion the resting urethral pressure profiles were preserved after division of the cauda equina but were lower in amplitude after overstretch of the autonomous bladder.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Blood-counts and folate assays were performed on samples from 102 adults at a residential institution for severe mental impairment. 96 of these patients were receiving anticonvulsant therapy and 6 were not. Only 1 subject had a macrocytic blood-picture, and 5 subjects had hypochromic anaemia. No features of incipient metaloblastic haemopoiesis were identified in the remaining samples. However, serum-folate measured by two assay methods was subnormal in 83% of the samples; red-cell folate was subnormal in 40%. It is concluded that the development of macrocytic anaemia in subjects on long-term anticonvulsants therapy is probably not related to the biochemical process which causes their low assayable folate but reflects inadequate nutrition.
We studied the first instance of aniridia-Wilms' tumor syndrome in twins who were mentally retarded. Both of them had congenital aniridia, cataracts, and glaucoma; only one subsequently developed a Wilms' tumor. A two-allele, two-step mutation is the most likely explanation of this genetically abnormal syndrome in twins. The aniridia-Wilms' tumor syndrome in twins further documents the relationship of teratogenic malformations and neoplasias.
The authors report the multi-institutional evaluation of a radioassay for serum folate utilizing a gamma-labeled folate analog (75Se-pteroyl-L-methylselenocysteine). The assay is run as a one-step simultaneous addition at ambient temperature and is completed within 45 minutes. The assay data were reproducible within four study centers and correlated with both the Lactobacillus casei diagnostic groups and the clinical pictures.
A variety of different methods have been used for the measurement of pressures during operations on the biliary tract. However, there are few data on the experimental evaluation of the methods, and there has been no controlled comparative evaluation of the most commonly used techniques. In these experiments, we have compared the manometric technique of Caroli, the syringe barrel method of Daniel and White et alii, and the constant infusion apparatus of Cushieri. The experiments were performed in pigs because of the similarity of their biliary tract to that of man. Resting and opening pressures were recorded, and flow into the duodenum via the ampulla was measured simultaneously. The manometric and syringe barrel techniques gave highly reproducible measurements of resting and opening pressure, and valid measurements of opening pressure. The constant infusion apparatus gave reproducible measurements of resting pressure, but did not measure opening pressure. The manometric technique was shown to measure changes in the resistance of the choledochoduodenal junction in response to morphine and atropine.
75Se-selenofolate radioassay was adapted for the purpose of red cell folate measurement. The results of assay of 124 whole blood samples by Lactobacillus casei microbiological assay and by radioassay using the adapted selenofolate method were concordant (r = 0.8). Red cell folate levels by the radioassay were below 170 microgram/1 in people who had haematological features of folate depletion. The distribution of results among reputedly healthy subjects extended down to 140 microgram/1.
These studies indicate that the monkey Macaca nemestrina provides a suitable model to evaluate the neurological mechanism of micturition. This animal has a sacral spinal center for micturition whereby the classification of primary patterns of neurogenic disorder into spinal reflex after suprasacral spinal cord section and autonomous after cauda equina section is validated. Attempts at dissociation of the spinal and vesical neurons by section of the cauda equina were characterized generally by raised rather than lowered tonus, irrespective of previous urinary diversion to prevent inadvertent overstretch of the bladder. No evidence was obtained to indicate that overstretch of the autonomous bladder is followed by loss of tonus but the survival times of the animals after cauda equina section were comparatively short. There was some indication that overstretch may induce coordinated contractility of the bladder when only the peripheral neuron and sympathetic innervation of the bladder are intact. Evidence was obtained that the monkey has a dual innervation of the mid urethra, in which the pressure profile is supported by alpha adrenergic receptors as well as some somatic neural control. The resting urethral pressure profile is preserved after low level section of the spinal cord or division of the cauda equina but is lower in amplitide after overstretch of the autonomous bladder.
Explore the source record for details and available documents.
We have used the vitrophage for combined lensectomy and vitrectomy in six eyes with congenital cataracts. No intraoperative complications were encountered. One week after operation four of the six eyes had clear corneas, and all eyes showed a bright red reflex. With follow-up ranging from 18 to 21 months all eyes had clear corneas and a view of the posterior pole consistent with 20/20 vision.
Intrathoracic stretch receptors regulate adjustments of the vasculature to gravitational changes and influence urinary water and solute excretion. Few reports of pathologic states involving interruption of these regulatory mechanisms have appeared. Two patients with orthostatic hypotenstion related to advanced intrathoracic carcinoma were studied, utilizing tilt-table examinations and immersion of the entire body in water to test the function of their intrathoracic baroreceptor reflex arcs. Both patients showed abnormalities of antidiuretic hormone level and sodium excretion as compared with normal controls. This suggests that total immersion is a safe and convenient test of the low-pressure baroreceptor system in patients with suspected dysfunction. Three patients are also reported whose charts were reviewed posthumously. Although they were not tested in the laboratory, their clinical data suggest that they too had been suffering from an interference with the transmission of impulses from the intrathoracic receptors.
Explore the source record for details and available documents.
Three hundred and eighty-two serum samples were assayed for folate content by a standard Lactobacillus casei microbiological assay and by radioassay using the 75Se-selenofolate radioassay kit from the Radiochemical Centre, Amersham. Results showed encouraging concordance. Explanations were discovered for the few disparities. The radioassay procedure is simple and an assay batch can be completed in one working day.
Unlike in all other thyroid preparations, exposure of dog thyroid cells in long-term monolayer culture to iodide (10(-7) to 10(-3) M for up to 19 h did not blunt the subsequent adenosine 3', 5'-cyclic monophosphate (cAMP) response to thyrotropin (TSH) stimulation. This lack of effect of iodide was observed even when confluent thyroid cells were "follicularized" by the action of TSH in the culture medium. Preincubation of these cells in thyroxine (T4) and triiodothyronine (T3) was similarly without effect on the subsequent cAMP response to TSH. Study of thyroid cells during the early phase of primary culture demonstrated that inhibition by iodide (10(-4) M) of the cAMP response to TSH occurred after 7 h but was lost after 48 h of cell culture. This inhibitory effect of iodide was prevented by the inclusion of methimazole in the preincubation medium. As with iodide-insensitive cells, T4 and T3 were without effect on the cAMP response to TSH in iodide-sensitive thyroid cells. Exposure of iodide-insensitive thyroid cells to iodide-containing medium obtained after 2 h of incubation with dog thyroid slices, as well as to medium enriched with the 100,000 g supernatant fraction of homogenates prepared from these thyroid slices, did not restore the inhibitory action of iodide. However, iodide-sensitivity of the cAMP response to TSH was restored by preincubation of iodide-insensitive cells in 10(-4) M iodide plus an H2O2-generating system (glucose-glucose oxidase). These data suggest that T4 and T3 are not organic iodine inhibitors of the thyroid cAMP response to TSH. In addition, they provide evidence against the existence of a soluble, freely diffusible, organic iodine inhibitor of thyroid adenylate cyclase. The loss of sensitivity to iodide inhibition of adenylate cyclase that occurs in thyroid cells shortly after initiation of primary culture appears to be related to a defect in the cellular organification mechanism, possibly the H2O2-generating system.