Defective processing and expression of thiazide-sensitive Na-Cl cotransporter as a cause of Gitelman's syndrome.

Gitelman's syndrome is an autosomal recessive disorder of salt wasting and hypokalemia caused by mutations in the thiazide-sensitive Na-Cl cotransporter. To investigate the pathogenesis of Gitelman's syndrome, eight disease mutations were introduced into the mouse thiazide-sensitive Na-Cl cotransporter and studied by functional expression in Xenopus oocytes. Sodium uptake into oocytes that expressed the wild-type clone was more than sevenfold greater than uptake into control oocytes. Uptake into oocytes that expressed the mutated transporters was not different from control. Hydrochlorothiazide reduced Na uptake by oocytes expressing the wild-type gene to control values but had no effect on oocytes expressing the mutant clones. Western blots of oocytes injected with the wild-type clone showed bands representing glycosylated (125 kDa) and unglycosylated (110 kDa) forms of the transport protein. Immunoblot of oocytes expressing the mutated clones showed only the unglycosylated protein, indicating that protein processing was disrupted. Immunocytochemistry with an antibody against the transport protein showed intense membrane staining of oocytes expressing the wild-type protein. Membrane staining was completely absent from oocytes expressing mNCC(R948X); instead, diffuse cytoplasmic staining was evident. In summary, the results show that several mutations that cause Gitelman's syndrome are nonfunctional because the mutant thiazide-sensitive Na-Cl cotransporter is not processed normally, probably activating the "quality control" mechanism of the endoplasmic reticulum.

Sry requires a CAG repeat domain for male sex determination in Mus musculus.

SRY, the mammalian Y-chromosomal sex-determining gene, encodes a protein characterized by a DNA-binding and -bending domain referred to as the HMG box. Despite the pivotal role of this gene, only the HMG box region has been conserved through evolution, suggesting that SRY function depends solely on the HMG box and therefore acts as an architectural transcription factor. In mice (genus Mus) Sry also includes a large CAG trinucleotide repeat region encoding a carboxy-terminal glutamine-rich domain that acts as a transcriptional trans-activator in vitro. The absence of this or any other potential trans-activating domain in other mammals, however, has raised doubts as to its biological relevance. To test directly whether the glutamine-rich region is required for Sry function in vivo, we created truncation mutations of the Mus musculus musculus Sry gene and tested their ability to induce testis formation in XX embryos using a transgenic mouse assay. Sry constructs that encode proteins lacking the glutamine-rich region were unable to effect male sex determination, in contrast to their wild-type counterparts. We conclude that the glutamine-rich repeat domain of the mouse Sry protein has an essential role in sex determination in vivo, and that Sry may act via a fundamentally different biochemical mechanism in mice compared with other mammals.

The human growth-arrest-specific gene GAS1 maps outside the candidate region of the gene for nevoid basal cell carcinoma syndrome.

The human growth-arrest specific gene GAS1 maps to chromosome bands 9q21.3-->q22, the region known to contain the tumour suppressor gene responsible for nevoid basal cell carcinoma syndrome (NBCCS). Because of its putative action as a tumour suppressor gene, the GAS1 gene was analysed as a candidate for the NBCCS gene. Using two-colour fluorescence in situ hybridization, the GAS1 gene maps outside the interval which, by genetic analysis, has been shown to contain the NBCCS gene.

Fine genetic mapping of the gene for nevoid basal cell carcinoma syndrome.

Nevoid basal cell carcinoma syndrome (NBCCS, or Gorlin syndrome) is a cancer predisposition syndrome characterized by multiple basal cell carcinomas and diverse developmental defects. The gene responsible for NBCCS, which is most likely to be a tumor suppressor gene, has previously been mapped to 9q22.3-q31 in a 12-cM interval between the microsatellite marker loci D9S12.1 and D9S109. Combined multipoint and haplotype analyses of additional polymorphisms in this region in our collection of Australasian pedigrees have further refined the localization of the gene to between the markers D9S196 and D9S180, an interval reported to be approximately 2 cM.

Further localization of the gene for nevoid basal cell carcinoma syndrome (NBCCS) in 15 Australasian families: linkage and loss of heterozygosity.

Nevoid basal cell carcinoma syndrome (NBCCS; basal cell nevus syndrome or Gorlin syndrome) is a cancer-predisposition syndrome characterized by multiple basal cell carcinomas (BCCs) and diverse developmental defects. The gene for NBCCS has been mapped to 9q23.1-q31 in North American and European families. In addition, loss of heterozygosity (LOH) for genetic markers in this region has been detected in sporadic BCCs, indicating that the NBCCS gene is probably a tumor-suppressor gene. In this study we have determined that the NBCCS gene is also linked to this region in Australasian pedigrees and that there is no significant evidence of heterogeneity. We have defined the localization of the gene by multipoint and haplotype analysis of 15 families, using four microsatellite markers. LOH at these loci was detected in 50% of sporadic BCCs, a rate that is significantly higher than that in other skin lesions used as controls.

Today, I closed my kitchen.

Cedars-Sinai Medical Center has recently switched to a kitchenless patient foodservice program. In addition to cutting 15 FTEs & contributing to nearly $500,000 in annual savings, foodservice has also released $1.5 million worth of real estate for revenue-generating activities.

RNA virus associated antigen in human placenta.

Using indirect immunofluorescence microscopy, it was demonstrated that human cytotrophoblast of six to ten weeks gestation contains mouse mammary tumor virus associated antigen. This antigen appeared predominantly in the periphery of the cells.

Food service needs controls to contain costs.

Cost containment can be achieved through the use of methods of measuring, controlling, and modifying food costs and quality, labor costs, and departmental procedures.

Ultrastructure of a primary fibrosarcoma of the human thyroid gland.

A primary fibrosarcoma of the thyroid occurring in a patient with a nodular goiter is described. Light microscopy showed interwoven bundles of spindle cells admixed with plump ovoid cells, and foci of multinucleated giant cells. Remnants of distorted thyroid follicles were found only at the periphery of the tumor. "Transitional" epithelial elements were not discernible but the tumor resembled an anaplastic giant cell carcinoma. Multiple blocks studied by electron microscopy, however, revealed that the tumor cells, including the giant cells, have the ultrastructure features of a fibroblast.

The Ask-Upmark kidney in a premature infant.

A premature infant with segmental hypoplasia of one kidney is reported. Since 1929 when Ask-Upmark first reported this renal anomaly and its association with hypertension, the nature of the lesion has remained in doubt. The question whether it is acquired post-natally or whether it is a developmental mal-formation has not been resolved. The case which we now report clearly documents the prenatal development of the lesion as well as its association with arrested nephrogenesis and the presence of abnormal vasculature. The cause of these changes is not clear, but it is suggested that ureteral reflux was present.

Pulmonary blastoma. Report of two cases in children.

Pulmonary blastoma is a rare tumor of the lung. Although it has been stated that this is predominantly a tumor of adults, a review of the 42 cases published to date reveals that it is a disease which occurs with some frequency in children. The tumor is relatively benign compared to pulmonary carcinosarcoma. Of the eight cases previously described in children, three are known to have survived and to be free of disease 10 months, 3 and 8 years after surgical resection. We report two additional cases of pulmonary blastoma in children followed for 34 and 26 months without any evidence of recurrence or metastases.

Pheochromocytoma with angiomatous features. A case report and ultrastructural study.

A functional pheochromocytoma of the adrenal gland but with an angiomatous histologic pattern was studied by light and electron microscopy. Although this tumor had typical clinical and gross anatomic features, its light microscopic appearance was unique and, to our knowledge, has not been previously described. Fine structural study provided insight into the intracellular pathways of catecholamine granule formation.

Rat polyvinyl sponge model for the study of infections: initial investigations.

Polyvinyl sponges were implanted subcutaneously on both sides of young female rats. One sponge was infected with 10(8) of either Escherichia coli K-12 F-, Staphylococcus aureus ATCC 25923, or Pseudomonas aeruginosa CDC 7725. P. aeruginosa remained at the inoculum level and S. aureus declined by 1 log, whereas E. coli was reduced 1,000-fold. Only P. aeruginosa was recovered from the blood in 36% of the animals in 24 h and in 20% of the rats in 48 h. The nutrient potential of rat inflammatory fluid was compared to nutrient broth by growth of each bacterium in untreated and heat-inactivated sponge fluids and Trypticase soy broth.