Bilateral spontaneous scapho-lunate subluxation treated by limited carpal fusion

The case of a 19 year-old-girl who developed spontaneous bilateral snapping scapho-lunate subluxation is described. Her symptoms were successfully treated by bilateral triscaphoid fusion.     

On the mechanism of increased potassium conductance by the potassium channel opener BRL 34915 in Isolated ventricular myocytes

The potassium conductance increased by BRL 34915 (BRL, cromakalim) was studied in single guinea pig ventricular myocytes by using a whole cell voltage-clamp technique. In control voltage-clamp recordings, the late current-voltage relation showed a distinct inward rectification. BRL (1–100 μM) shortened the action potential and diminished or abolished inward rectification but had no effect on the slope conductance and currents flowing during hyperpolarizing clamp steps. BRL did not decrease the slow inward current but accelerated the time constant of activation and amplitude of the outward current. Cd markedly decreased (0.2 mM) or abolished (0.4–0.6 mM) the slow inward current and BRL induced a faster outward shift of late current to a greater value. Glybenclamide (10 μM), a blocker of ATP-sensitive K⁺ channels, had little effect of its own on action potential, membrane currents, and I-V relation. However, in the presence of BRL, glybenclamide abolished BRL effects on action potential and currents and restored inward rectification. It is concluded that the mechanism by which BRL shortens the action potential is a faster growth of an outward current due to the reduction or abolition of the inward rectification of an ATP-dependent potassium channel. The reduction in force in non-isolated tissues appears to be an indirect result of the action potential shortening and not of a decreased slow inward current.     

Leukotriene receptor antagonists. 2. The [[(tetrazol-5-ylaryl)oxy]methyl]acetophenone derivatives

A series of [[(tetrazol-5-ylaryl)oxy]methyl]acetophenones was synthesized and evaluated as antagonists of leukotriene D4 induced contractions of guinea pig ileum. Substitutions at the 3-position of the acetophenone with ethyl (66), propyl (68), butyl (83), and isobutyl (84) gave -log IC50 values of 7.9, 8.0, 7.8, and 7.7, respectively. Equally potent compounds were obtained when the tetrazol-5-yl group was connected to the second benzene ring in the para position with a chemical bond (67), methylene (68), or ethylene (71). For retention of high antagonist activity, the acetophenone should be substituted in the 2-position by a hydroxyl group and the tetrazole ring should have an acidic hydrogen atom. 1-[2-Hydroxy-3-propyl-4-[[4-(1H-tetrazol-5-ylmethy) phenoxy]methyl]phenyl]ethanone (68, LY1632443) has undergone extensive pharmacologic evaluation for its potential as an antiasthma agent.     

Tumor vascular signals in renal masses: detection with Doppler US

The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses.     

Evaluation of several film/screen combinations for megavoltage radiation therapy treatment field verification

The introduction of a lower cost alternative to a film commonly used for megavoltage radiation therapy port films led to a comparison of two films (Kodak X-TL and X-OMAT G) in four metal screen cassette configurations. In addition to determination of H-D curves and point spread functions, images of humanoid phantom sections were obtained and evaluated for clinical "usefulness." The X-OMAT G film-screen combinations compared favorably with the X-TL film combinations with respect to the H-D Curves and point spread functions but there was a slight preference for X-TL film. There were no differences noted whether the film was used in the standard "ready pack" or naked in the cassettes.     

Pathological, immunocytochemical and microbiological findings in calf pneumonias associated with Haemophilus somnus infection

Pathological, immunocytochemical and microbiological findings in 32 cases of calf pneumonia associated with Haemophilus somnus infection are described. The majority of cases were "found dead" or died after a sudden onset pneumonia of less than 24 h duration. Lesions of exudative bronchopneumonia were present and the cases could be divided into two main groups on the basis of histopathological and immunocytochemical features. In group A, cases were dominated by necrotizing bronchiolitis, degeneration and necrosis of airway and alveolar exudates, severe alveolitis with accumulations of degenerate basophilic cells, interstitial inflammatory changes and the widespread distribution of H. somnus antigen in airways and alveoli. In Group B, necrotizing and degenerative changes were much less extensive and less severe and the overall appearance was of suppurative bronchopneumonia with H. somnus antigen much less widespread within the lungs. Alveolar oedema, hyaline membrane formation and alveolar epithelial hyperplasia were present in caudodorsal lung areas of several calves. No major differences were seen between the histopathology of lungs where H. somnus was the sole isolate and that of lungs where H. somnus was isolated along with other bacterial pathogens.     

Evaluation of the differentiation potential of WB-F344 rat liver epithelial stem-like cells in vivo. Differentiation to hepatocytes after transplantation into dipeptidylpeptidase-IV-deficient rat liver.

After intrahepatic transplantation into livers of adult syngeneic German-strain Fischer 344 rats that are deficient for the bile canalicular enzyme dipeptidyl peptidase IV (DPP-IV), cultured WB-F344 rat liver epithelial cells (without exogenous marker genes) integrate into hepatic plates and differentiate into hepatocyte-like cells that are morphologically and functionally indistinguishable from mature hepatocytes. In this model system, the differentiated progeny of transplanted WB-F344 cells are identified among the DPP-IV-negative host hepatocytes by their expression of bile canalicular DPP-IV enzyme activity. DPP-IV-positive hepatocyte-like cells also expressed other markers of hepatocytic differentiation, including albumin, transferrin, and alpha-1-antitrypsin, suggesting that the progeny of transplanted WB-F344 cells express a complete hepatocyte differentiation program. These results complement our previous studies indicating WB-F344 cells can serve as stem-like precursor cells for differentiated hepatocytes and strengthen the suggestion that WB-F344 rat liver epithelial cells represent the cultured counterpart of liver stem-like hepatocyte progenitor cells present in the normal adult rat liver.