Biomedical subjects

J Garvin

Publications and source records attributed to J Garvin.

23 records · Page 2Linked to original sources

PubMed1992

The diagnosis of abdominal neuroblastoma: relative roles of ultrasonography, CT, and MRI.

Abdominal neuroblastoma is reviewed in terms of its diagnosis, including in utero, at birth, and through infancy into childhood. Age at diagnosis remains the best predictor of survival, with infants under 1 year of age having almost 100% cure. Ultrasonography and magnetic resonance imaging (MRI) are the recommended diagnostic modalities to stage the abdominal primary, although computed tomography (CT) (including myelography) is still widely and efficiently used. Examples are given of each stage.

Abdominal Neoplasms↗

PubMed1991

Endothelin inhibits fluid and bicarbonate transport in part by reducing Na+/K+ ATPase activity in the rat proximal straight tubule.

The effects of endothelin on fluid and bicarbonate absorption and Na+/K+ ATPase activity in the proximal straight tubule were investigated. During the control period, fluid absorption was 0.59 +/- 0.03 nL/mm.min when tubules were perfused at 4.76 nL/mm.min. After treatment with 10(-9) M endothelin, fluid absorption fell to 0.36 +/- 0.06 nL/mm.min when perfused at a similar flow rate. During the control period, bicarbonate absorption was 67.9 +/- 3.6 pmol/mm.min. After treatment with endothelin, it fell to 42.8 +/- 4.3 pmol/mm.min, an inhibition of 38%. To test whether inhibition of fluid and bicarbonate absorption was due to suppression of Na+/K+ ATPase activity, the effect of endothelin on pump activity was investigated. In control tubules, Na+/K+ ATPase activity was 85 +/- 5 pmol/mm.min. In endothelin-treated tubules, Na+/K+ ATPase activity was 68 +/- 4 pmol/mm.min, a reduction of 20%. From these data, it was concluded that endothelin inhibits fluid and bicarbonate transport in the proximal tubule and that this inhibition is in part due to suppression of Na+/K+ ATPase activity.

Animals↗

PubMed1990

N-myc oncogene expression and amplification in metastatic lesions of stage IV-S neuroblastoma.

The authors determined the levels of N-myc oncogene amplification and RNA expression in three infants with metastatic neuroblastoma. By clinical staging Patients 1 and 2 were Stage IV-S, a disease with limited metastatic potential and generally favorable outcome; Patient 3 was Stage IV. Southern blots of chromosomal DNA showed normal N-myc copy number in the primary tumor of Patient 1, extensive (200-fold) gene amplification in the primary tumor from Patient 2, and intermediate (100-fold) gene amplification in the primary tumor and metastatic lesions from Patient 3. N-myc RNA was expressed in all of the primary and metastatic tumor tissues tested. The level of N-myc RNA expression roughly corresponded to the extent of N-myc gene amplification in Patients 2 and 3 and was overexpressed from a single N-myc gene copy in Patient 1. N-myc gene amplification and RNA expression levels were approximately the same in the primary and metastatic lesions for each of the patients tested. The two patients with N-myc gene amplification had a poor outcome, but the patient with normal N-myc gene copy number had no evidence of disease. Despite the clinical picture in Patient 2 of Stage IV-S neuroblastoma, the pattern of N-myc amplification and expression more closely resembled that of Patient 3 (Stage IV neuroblastoma) than that of Patient 1 (bona fide Stage IV-S neuroblastoma).

Gene Amplification↗

PubMed1990

Cystic fibrosis in a black child with hemoglobin S-D disease.

A 9-year-old black patient with the simultaneous occurrence of cystic fibrosis and hemoglobin S-D disease is reported. She was placed on chronic transfusion therapy from 1 year of age because of her rapidly worsening pulmonary condition. Her pulmonary function is now stable. The role of this therapy in the overall management of this unusual syndrome is discussed.

Black People↗

PubMed1978

Study of a kindred with partial deficiency of red cell 2,3-diphosphoglycerate mutase (2,3-DPGM) and compensated hemolysis.

A kindred with partial deficiency of red cell 2,3-diphosphoglycerate mutase (2,3-DPGM) was studied. The propositus presented with indirect hyperbilirubinemia, normal hemoglobin (15.8 g/dl), and elevated reticulocyte count (4.6%). The red cell 51Cr survival was decreased (tau1/2 16 days). Incubated osmotic fragility was normal; autohemolysis was increased and corrected with glucose and ATP. The P50 was 18.5 mm Hg (normal 25.5 +/- 3), but the stability, electrophoresis, and fingerprinting of hemoglobin were normal. The concentration of 2,3-diphosphoglycerate (2,3-DPG) was reduced to 43% of normal. Red cell 2,3-DPGM was decreased to 59% of normal; 2,3-DPG phosphatase was similarly decreased. All red cell glycolytic and hexose monophosphate shunt enzymes, glycolytic intermediates other than 2,3-DPG, and glucose consumption and lactate production were normal. Five family members showed similar hematologic findings. The deficiency appears to be secondary to decreased enzyme synthesis and to be inherited as an autosomal dominant trait in this family. Partial deficiency of 2,3-DPGM should now be considered in the differential diagnosis of compensated hemolysis associated with increased oxygen affinity.

Adult↗