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M S Rabin

Publications and source records attributed to M S Rabin.

17 recordsLinked to original sources
PubMed1991

Selective targeting of gene products with the megakaryocyte platelet factor 4 promoter.

We have used the 1.1 kilobases of the 5' upstream region of the platelet factor four (PF4) gene coupled to the prokaryotic beta-galactosidase gene to generate two lines of transgenic mice that express this construct. Studies of blood, bone marrow, spleen, and thymus reveal that platelets are the only circulating blood cells and megakaryocytes are the only hematopoietic precursor cells that possess the prokaryotic enzyme. The lack of transgene expression in brain, heart, intestine, kidney, liver, lung, and skeletal muscle was established by in situ staining of tissue sections as well as kinetic assay of tissue homogenates. These data suggest that this domain of the PF4 promoter contains most, if not all, of the tissue-specific region of the gene. Unexpectedly, the adrenal gland exhibits approximately 2% of the levels of beta-galactosidase possessed by megakaryocytes and the distribution of the prokaryotic enzyme corresponds to the location of mineralocorticoid-secreting cells. This result implies that either the PF4 gene is transcribed at low levels in specialized adrenal cells or that these specialized endocrine cells possess trans-acting factors similar to those that control the megakaryocyte promoter. The selective high-level expression of transgenes linked to the PF4 promoter should allow us to augment or suppress the in vivo levels of critical components in megakaryocytes and platelets and subsequently ascertain the effects of these modifications.

Animals↗
PubMed1986

The tumor promoter phorbol 12-myristate 13-acetate induces a program of altered gene expression similar to that induced by platelet-derived growth factor and transforming oncogenes.

Treatment of mouse NIH 3T3 cells with the phorbol ester tumor promoter, phorbol 12-myristate 13-acetate, results in altered transcription of several genes as measured in nuclear run-off experiments. The first set of genes, whose altered transcription occurs rapidly in the absence of protein synthesis, is typified by induction of c-myc and c-fos and decreased transcription of alpha 2 type I procollagen. This work demonstrates the existence of a second class of genes whose rapidly increased transcription requires prior protein synthesis, which is represented by the gene encoding a secreted lysosomal protein, MEP. Similar induction of MEP RNA is seen after treatment with platelet-derived growth factor or transformation with Kirsten sarcoma virus.

Actins↗
PubMed1979

The 'riding' ulcer: A report of 3 cases.

Hiatal hernia with ulceration at the level of the diaphragm is a well-recognized and not uncommon condition. These ulcers may be simple gastric ulcers in patients who coincidentally have a hiatal hernia, or they may be related to trauma of the stomach against the diaphragm. They are not always readily detected on barium study. The clinical and radiological features in 3 recent cases are described, together with a brief review of the literature.

Aged↗
PubMed1979

Choledochocele. A case report.

A case of a young man with a choledochocele is presented. The entity is rare and symptoms are usually nonspecific. Pre-operative diagnosis is often not made but is usually possible provided both barium study and cholangiography are performed. The clinical presentation and diagnosis are discussed.

Adult↗
PubMed1979

High frequency of mutation to tubercidin resistance in CHO cells.

The acquisition of high-level resistance to tubercidin (an adenosine analog) in CHO cells occurs in a single step at high frequency (10(-3) to 10(-4)) without mutagenesis. Analysis of a large number of independent mutants by a fluctuation test (Luria and Delbruk, 1943) indicates that they arise independently of the selection medium and all fall into the same complementation group. All mutants tested lack detectable adenosine kinase activity. An analysis of hybrids between mutant and wild-type cells indicates that resistance to tubercidin is a recessive marker which segregates as would be expected if it were a haploid locus in the parental CHO cell. Resistance to tubercidin is not linked to the X chromosome in CHO cells and appears to occur at much lower frequency in primary Chinese hamster cells and other cultured cell lines.

Animals↗
PubMed1979

Radiological changes of reflux oesophagitis.

Early changes in reflux oesophagitis are difficult to assess on radiological criteria (Torrance, 1973). The later manifestations, particularly with stricture formation, are best assessed by barium swallow. Apart from stricture formation, marked reflux oesophagitis with coarsened folds may lead to a mistaken diagnosis of varices or carcinoma. The various radiological appearances that have been encountered are described.

Adult↗
PubMed1978

Caecal bascule--a potential clinical and radiological pitfall. Case reports.

Caecal volvulus is usually associated with a twisted caecum, seen to occupy the umbilical area or left hypochondrium on radiography. Caecal bascule refers to the form of volvulus in which the distended caecum is situated within the pelvis. The caecal bascule type of obstruction is uncommon, and clinical and radiological appearances may be confusing. Two cases are presented and the incidence, pathogenesis and radiological features are discussed.

Adult↗
PubMed1978

Pneumatosis coli secondary to colonic obstruction. A case report.

A case of pneumatosis coli of the caecum and ascending colon with a closed loop obstruction secondary to carcinoma of the descending colon is presented. The caecum was grossly distended and impending rupture was diagnosed. It is postulated that complete transmural rupture of the caecum was prevented by partial decompression of caecal air into the bowel wall.

Aged↗
PubMed1978

Value of the mandibular radiograph in familial polyposis coli.

Familial polyposis coli and Gardner's syndrome have identical colonic manifestations. Recent evidence has shown that both conditions are associated with occult osteomatous lesions in the mandible. We present 3 patients from 2 families with familial polyposis coli who, in addition to the colonic lesions, also had occult osteomatous mandibular lesions. The value and practical application of radiography of the mandible as an additional diagnostic aid in familial polyposis coli are emphasized.

Adolescent↗
PubMed1977

Benign gastric ulcer as a cause of gastrocolic fistula. A report of 3 cases.

Three cases of gastrocolic fistula due to benign gastric ulcer seen during a 5-year period are presented. Although colonic or gastric malignancy is said to be the commonest cause of gastrocolic fistula, in the same period only 1 case due to colonic carcinoma was seen. The important role played by radiology in the diagnosis of gastrocolic fistula is emphasized and the clinical presentation is discussed, together with the possible role of analgesics in the aetiology.

Aged↗