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R Yung

Publications and source records attributed to R Yung.

24 records · Page 2Linked to original sources

Ceftazidime versus imipenem-cilastatin as initial monotherapy for febrile neutropenic patients.

One hundred febrile episodes in 89 neutropenic patients after cytotoxic chemotherapy were randomized to be treated with either ceftazidime or imipenem as initial monotherapy. The clinical characteristics of the two groups of patients were comparable. The response of the fever in patients who received imipenem was significantly better than that in those who received ceftazidime (77 versus 56%, respectively; P = 0.04), especially in those with microbiologically documented infection (81 versus 33%, respectively; P = 0.02). The in vitro susceptibilities and the clinical responses suggested that, with the possible exception of Pseudomonas spp., imipenem was more effective than ceftazidime in treating neutropenic infections caused by both gram-positive and -negative organisms. An additional 23 and 21% of the patients in the ceftazidime and imipenem groups, respectively, responded to the addition of cloxacillin and amikacin following failure of monotherapy. The majority of the treatment failures, relapses, and superinfections were related to resistant infective organisms such as methicillin-resistant Staphylococcus spp. and Pseudomonas spp. or disseminated fungal infections.

Adolescent↗

Effect of intracameral carbachol on intraocular pressure after cataract extraction.

Thirty-two patients were randomly assigned to a treatment or a control group to determine the dose-response and duration of action of intracameral carbachol on immediate postoperative intraocular pressure after extracapsular cataract extraction using a viscoelastic substance. Patients in the treatment group received 0.5, 0.25, or 0.1 ml of 0.01% intracameral carbachol. Patients in the control group received 0.1 or 0.5 ml of balanced salt solution. Intraocular pressures of all patients were measured preoperatively and at three, six, 12, 24, and 48 hours postoperatively. The control group as a whole showed a 9.5-mm Hg intraocular pressure rise at three hours, a 10.0-mm Hg rise at six hours, a 9.0-mm Hg rise at 12 hours, and a 7.2-mm Hg rise at 24 hours postoperatively. The group treated with 0.5 ml of carbachol maintained stable intraocular pressures through the 48-hour measurement period. The groups treated with 0.25 and 0.1 ml of carbachol maintained stable intraocular pressures through 24 hours postoperatively. The differences in intraocular pressure were statistically significant for all treated groups through the 24-hour measurement.

Carbachol↗

Imipenem/cilastatin as initial therapy for febrile neutropenic patients.

Imipenem 2 g daily was administered intravenously to 40 evaluable patients with neutropenia and fever. Twenty-three patients had acute leukaemia and 17 malignant lymphoma. The overall response rate was 70.0%. Of the 14 patients with documented infection, 9 (64.3%) responded. Poorer responses were observed in patients with pneumonia (40%) or pseudomonal infection (50%). The response rate was significantly higher among patients with increasing neutrophil counts during therapy (P less than 0.02). Fungal infection was a common cause of treatment failure. Gastrointestinal side effects and skin rashes were occasionally seen. No patient developed central nervous system toxicity. Imipenem is a practical alternative to antibiotic combinations for management of neutropenic infection. However, careful monitoring is essential in the subgroups of patients with pneumonia or pseudomonal infections, who may require modifications of therapy.

Agranulocytosis↗

Effect of dietary carbohydrate on monosaccharide uptake by mouse small intestine in vitro.

Using intestinal sleeves in vitro, we studied the effect of dietary carbohydrate on active monosaccharide uptake in mice. Dietary carbohydrate did not affect numerous parameters of intestinal structure, such as length, circumference, weight, protein content, villus dimensions and density, and area at the villus level. Mice on a carbohydrate-free diet had active D-glucose uptake relatively independent of position along the small intestine. A carbohydrate-containing diet reversibly and within 1 day stimulated uptake except in the ileum, restoring the proximal-to-distal gradient in glucose uptake normally observed. This stimulation involved a 81-116% increase in the Michaelis- Menton constant Vmax, and also an apparent increase in the Michaelis- Menton constant Km, that may however be an artifact arising from unstirred-layer effects. Active uptake of 3-O-methyl-D-glucose also increased, permeability to glucose remained unchanged, and proline uptake reversibly decreased (probably due to the lower protein content of the carbohydrate-containing diets). The effect of fasting on active monosaccharide uptake seemed largely due to withdrawal of dietary carbohydrate, rather than of calories per se. It is concluded that dietary carbohydrate causes induction of monosaccharide carriers in the intestine, along with its more familiar induction of pancreatic amylase and intestinal disaccharidases. Substrate-dependent carrier induction may be physiologically significant in maintaining the proximal-to-distal gradient of glucose transport. An appendix presents measurements of villus area as a function of position along the intestine.

3-O-Methylglucose↗

Extracellular matrix-sarcolemmal surface interconnections: a quick-freeze deep-etch study.

Using ultrarapid freezing and deep-etch fracture techniques, the extracellular matrix in unfixed rabbit papillary muscles is seen to consist of an extensive network of collagen, microfibrils, and microthreads. The microfibril-microthread lattice appears to weave around collagen fibers connecting them to each other and to the external lamina of the sarcolemma. The external lamina appears to insert into the bilayer via trabeculae. With 10 min exposure to zero-Ca solution, the external lamina of the myocytes detaches from the membrane surface but is held from complete removal by some remaining trabecular attachments. This detachment of external lamina affords a view for the first time of the surface of the myocardial sarcolemma. Particles of varying sizes (6-13 nm) may represent the external portions of some integral proteins or protein molecules associated with the membrane surface. They can also represent attachment sites of the external lamina. The serious risks for the fibrous network structure representing an artifact caused by precipitation of matrix proteins during deep etching are discussed.

Animals↗