Pituitary stalk meningioma: case report

We report a 45-year-old woman with a meningioma which was in contact with only the pituitary stalk on MRI. As the pituitary stalk has no dura mater, we suggest this tumour may have originated from the arachnoid membrane of the pituitary stalk. Though some reports have shown that meningiomas can arise from sites lacking a dural component, this is the first report of a meningioma originating from the pituitary stalk. Received: 21 December 1995 Accepted: 26 February 1996     

Clinical examination of ceftibuten in acute bronchitis

Clinical evaluation of ceftibuten (CETB, 7432-S) was performed in 20 patients with acute bronchitis. They were consisted of 10 males and 10 females aged from 20 to 80 years old. CETB was given orally in daily dose of 300 mg (18 cases) or 600 mg (2 cases) in three divided portions. The duration of administration was 3 to 14 days. Especially they were given for 7 days in 16 cases. A total of 11 strains comprising 4 strains of Staphylococcus aureus, 2 strains of beta-Streptococcus and 1 strain each of Streptococcus pneumoniae, Branhamella catarrhalis, Klebsiella oxytoca, Serratia marcescens, Acinetobacter lwoffii were identified from sputa before administration. All of the above bacteria were eradicated but, in 1 case, a strain of Streptococcus pyogenes appeared after the treatment (eradication ratio = 100%). The clinical efficacy rate was 100%: Responses were excellent in 3 cases and good in 17 cases. There was no side effect and no abnormal changes in laboratory test results. From the avobe results, it is concluded that CETB is effective, safe and useful new oral cephem on acute bronchitis.     

Interleukin-1 up-regulates transcription of its own receptor in a human fibroblast cell line TIG-1: role of endogenous PGE2 and cAMP.

The regulation of interleukin-1 receptor (IL-1R) mRNA expression by IL-1 in a human lung fibroblast cell line (TIG-1) was investigated. After 2 h of stimulation with human recombinant IL-1 alpha or IL-1 beta, the levels of T cell/fibroblast-type IL-1R mRNA increased, and the elevation was sustained for at least 72 h. IL-1 also stimulated synthesis of prostaglandin E2 (PGE2) and secondary cAMP accumulation. Exogenously added PGE2 increased the levels of both IL-1R mRNA and intracellular cAMP. Forskolin, cholera toxin and 8-Bromo adenosine (8-Br-cAMP) all increased IL-1R mRNA levels. Indomethacin blocked IL-1 stimulation of IL-1R mRNA expression, PGE2 production and cAMP. 125I-labeled IL-1 alpha-binding studies showed that this cell line expresses 2.6 x 10(4) IL-1R per cell with a Kd of 5.1 x 10(-10) M. After treatment of the cells with IL-1, the level of IL-1R increased over that of control cells. PGE2 also increased IL-1R without alteration in its affinity. Cross-linking experiments indicate that this cell line expresses the 80-kDa receptor molecule before and after treatment with PGE2; the molecular mass corresponds to the T cell/fibroblast type I IL-1R. These results indicate that IL-1 does not directly stimulate expression of IL-1R mRNA or cell surface IL-1R, but only indirectly by stimulation of endogenous PGE2.     

Percutaneous removal of renal and upper ureteral stones: clinical results and complications of 103 cases

We report the results and complications of 103 consecutive patients who underwent percutaneous removal of renal and ureteral stones. The overall clinical success rate was 80.6%. For the recent 33 cases in which UL-arm fluoroscopy was used, however, the success rate was as high as 87.9%, which was considered to be due to easier establishment of percutaneous direct access. The most common complications were bleeding (18.5%), extravasation (15.5%) and fever (9.7%). Four cases with significant bleeding required arteriography, but there were no sign of arteriovenous fistula nor pseudoaneurysms in any cases. To study renal parenchymal damage in the percutaneous procedures, plasma renin activities (PRA) were compared in 54 cases after six months. However, significant elevation of PRA did not occur in any case.     

Dual Effects of Hexanol and Halothane on the Regulation of Calcium Sensitivity in Airway Smooth Muscle

Background: Contraction of airway smooth muscle is regulated by receptor-coupled mechanisms that control the force developed for a given cytosolic calcium concentration (i.e., calcium sensitivity). Halothane antagonizes acetylcholine-induced increases in calcium sensitivity by inhibiting GTP-binding (G)-protein pathways. The authors tested the hypothesis that hexanol, like halothane, inhibits agonist-induced increases in calcium sensitivity in airway smooth muscle by inhibiting G-protein pathways.

Methods: Calcium sensitivity was assessed using [alpha]-toxin-permeabilized canine tracheal smooth muscle. In selected experiments, regulatory myosin light chain phosphorylation was also determined by Western blotting in the presence and absence of 10 mm hexanol and/or 100 [mu]m acetylcholine.

Results: Hexanol (10 mm) and halothane (0.76 mm) attenuated acetylcholine-induced calcium sensitization by decreasing regulatory myosin light chain phosphorylation during receptor stimulation. Hexanol also inhibited increases in calcium sensitivity due to direct stimulation of heterotrimeric G-proteins with tetrafluoroaluminate but not with 3 [mu]m GTP[gamma]S, consistent with prior results obtained with halothane. In contrast, in the absence of receptor stimulation, both compounds produced a small increase in calcium sensitivity by a G-protein-mediated increase in regulatory myosin light chain phosphorylation that was not affected by pertussis toxin treatment.     

Anesthetics Inhibit Membrane Receptor Coupling to the Gq/11 Heterotrimeric G Protein in Airway Smooth Muscle

Background: Some anesthetics relax airway smooth muscle in part by inhibiting acetylcholine-induced increases in Ca2+ sensitivity, an effect associated with inhibition of guanosine nucleotide exchange at the [alpha] subunit of the Gq/11 (G[alpha]q/11) heterotrimeric G protein. This study tested the hypothesis that these anesthetic effects are not unique to the muscarinic receptor but are a general property of the heptahelical receptors that increase Ca2+ sensitivity in airway smooth muscle.

Methods: Anesthetic effects on agonist-induced increases in Ca2+ sensitivity were measured in porcine airway smooth muscle strips permeabilized with S. aureus [alpha]-toxin. Anesthetic effects on basal (without agonist stimulation) and agonist-promoted G[alpha]q/11 guanosine nucleotide exchange were determined in crude membranes prepared from porcine airway smooth muscle. The nonhydrolyzable, radioactive form of guanosine 5'-triphosphate was used as the reporter for nucleotide exchange at G[alpha]q/11.

Results: Acetylcholine, endothelin-1, and histamine caused a concentration-dependent increase in Ca2+ sensitivity. Halothane (0.67 +/- 0.07 mm) and hexanol (10 mm) significantly inhibited the increase in Ca2+ sensitivity induced by each agonist. Each agonist also caused a time- and concentration-dependent increase in G[alpha]q/11 nucleotide exchange. Neither anesthetic had an effect on basal G[alpha]q/11 nucleotide exchange, whereas halothane and hexanol significantly inhibited the increase in G[alpha]q/11 nucleotide exchange promoted by each agonist.     

Microheterogeneity of regional myocardial blood flows in low-perfused rat hearts evaluated by double-tracer digital radiography.

Using (3)H- and (125)I-labeled desmethylimipramine (DMI) for regional flow tracers, we established a two-time measurement method for the spatial pattern of myocardial perfusion in cross-circulated rat hearts. Myocardial extractions and retentions of these tracers were confirmed to be satisfactory; however, the latter were less than 90% after 3 min at a perfusion rate of 2.9 ml/min/g, limiting the present application to a short-time perfusion measurement. Distributions of myocardial depositions were separated by subtraction digital radiography with 400-microm pixel resolution. Its feasibility was examined by regression analysis between local deposition densities of (3)H- and (125)I-DMI injected simultaneously. The slope, y-intercept, and correlation coefficient (r) of the regression line were 0.98+/-0.04, 0.02+/-0.04, and 0.95+/-0.03, respectively, indicating the validity of the present image subtraction technique. The spatial pattern of myocardial perfusion in response to flow reduction was evaluated by the injections of (3)H- and (125)I-DMI, respectively, before and after a nearly 70% flow reduction. A significant correlation between normalized density distributions of these tracers was found in both subepicardium (r=0.77+/-0.12) and subendocardium (r=0.73+/-0.20), indicating the stable pattern of myocardial perfusion. However, the coefficient of variation of tracer densities showed a decrease of subendocardial flow heterogeneity from 35+/-15% to 31+/-16%. Thus, flow differences between originally high- and low-flow regions in subendocardium were reduced on a relative basis during low perfusion.