Increased urinary thyroxine sulfate excretion in thyroxine therapy

The efficiency of hemato-C-cellular transport of calcitonin into the systemic blood flow was evaluated by the methods of statistical modelling. The linear regression model obtained on 36 rats suggests essential predetermination of the serum concentrations of calcitonin (CT) by the intensity of incretory activity of the thyroid parafollicular epithelium: CT = 13.733+ (0.318 Nvsg; rxy = 0.830; p < 0.001 (Nvsg is numerical density of the sublemmal granules on the C-cells vascular pole). At the same time, the resulting index (CT) depends not only on Nvsg. This index is also influenced by the factors not controlled by the model, such as Hemato-C-cellular delay of calcitonin. These factors determine each certain proportion of the error of prognostication of the calcitonin serum content according to Nvsg. A covariation model CT = bNvsg was plotted in order to determine the total influence of uncontrolled factors. Its error of prognostication was subject to analysis of variance and a confidence interval of biological accessibility of endogenous calcitonin was calculated (73% < FCT < or = 100%; p > or = 0.95). The results obtained suggest the absence of essential intrathyroid loss of calcitonin at the transinterstitial and transmural stages of hemato-C-cellular hormone transfer.     

The effect of isosorbide dinitrate following experimental coronary occlusion

A new case, the third in Israel, of subcutaneous sporotrichosis is presented. A pigmentary strain of Sporothrix schenckii was cultured from the unopened and necrotic nodules of the left hand and forearm of an 80-year-old male. Experimental inoculation of the isolated fungus into mice led to the dissemination of the organism in the liver, kidneys and lungs inoculated intraperitoneally, and the development of orchitis with abscess formation in those inoculated intratesticularly. In both groups of mice the causative agent was successfully recovered. Three months of treatment with oral potassium iodide led to the disappearance of the lesions. The source of contamination was found to be the soil adhering to fragments of wood. Two strains of a fungus, morphologically identical to the human S. schenckii, were isolated through the mouse procedure and agar-plating method from soil samples collected in the vicinity of the patient's residence. The soil isolates also proved to be pathogenic in animal inoculation. This is the first isolation of S. schenckii from soils in Israel. The possible relationships between the soil isolates and Ceratocystis stenoceras are discussed.     

The one-eyed pinhead gene functions in mesoderm and endoderm formation in zebrafish and interacts with no tail

The zebrafish locus one-eyed pinhead (oep) is essential for the formation of anterior axial mesoderm, endoderm and ventral neuroectoderm. At the beginning of gastrulation anterior axial mesoderm cells form the prechordal plate and express goosecoid (gsc) in wild-type embryos. In oep mutants the prechordal plate does not form and gsc expression is not maintained. Exposure to lithium, a dorsalizing agent, leads to the ectopic induction and maintenance of gsc expression in wild-type embryos. Lithium treatment of oep mutants still leads to ectopic gsc induction but not maintenance, suggesting that oep acts downstream of inducers of dorsal mesoderm. In genetic mosaics, wild-type cells are capable of forming anterior axial mesoderm in oep embryos, suggesting that oep is required in prospective anterior axial mesoderm cells before gastrulation. The oep gene is also essential for endoderm formation and the early development of ventral neuroectoderm, including the floor plate. The loss of endoderm is already manifest during gastrulation by the absence of axial-expressing cells in the hypoblast of oep mutants. These findings suggest that oep is also required in lateral and ventral regions of the gastrula margin. The sonic hedgehog (shh).gene is expressed in the notochord of oep animals. Therefore, the impaired floor plate development in oep mutants is not caused by the absence of the floor plate inducer shh. This suggests that oep is required downstream or in parallel to shh signaling. The ventral region of the forebrain is also absent in oep mutants, leading to severe cyclopia. In contrast, anterior-posterior brain patterning appears largely unaffected, suggesting that underlying prechordal plate is not required for anterior-posterior pattern formation but might be involved in dorsoventral brain patterning. To test if oep has a wider, partially redundant role, we constructed double mutants with two other zebrafish loci essential for patterning during gastrulation. Double mutants with floating head, the zebrafish Xnot homologue, display enhanced floor plate and adaxial muscle phenotypes. Double mutants with no tail (ntl), the zebrafish homologue of the mouse Brachyury locus, display severe defects in midline and mesoderm formation including absence of most of the somitic mesoderm. These results reveal a redundant function of oep and ntl in mesoderm formation. Our data suggest that both oep and ntl act in the blastoderm margin to specify mesendodermal cell fates.