Biomedical subjects

D Rader

Publications and source records attributed to D Rader.

4 recordsLinked to original sources

PubMed1992

Laparoscopic unroofing of a renal cyst.

Excision of a renal cyst via the flank approach results in a painful postoperative recovery requiring several days of hospitalization. We used laparoscopy in a selected patient to unroof a large complex renal cyst. The technique could optimally be used for simple cysts. The procedure was minimally traumatic, morbidity was negligible and the patient was discharged from the hospital the morning after the operation. After a 6-month followup, we believe that this laparoscopic technique is a significant advance in urological surgical management and may be better indicated for symptomatic, recurrent, simple renal cysts.

Female↗

PubMed1992

Thyroxine binding to the apolipoproteins of high density lipoproteins HDL2 and HDL3.

Four preparations of high density lipoprotein HDL2, five of HDL3, and purified apolipoproteins apoA-I, apoA-IV, and apoE were photoaffinity labeled with [125I]T4 and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Gels were also immunoblotted with antiserum against apoA-I, apoA-II, apoA-IV, apoE, or apo(a), and the immunostained membrane was then autoradiographed. In HDL2, the two major radioactive bands migrated near the origin of the resolving gel and at 28-31 kilodaltons (kDa). The first band, stained by anti-apo(a) and anti-apoB-100, accounted for 40-96% of the total radioactivity and was attributed to lipoprotein(a), which is isolated in the same density range as HDL2. The second band, stained by anti-apoA-I, accounted for 1-57% [41-95% after correction for contaminating lipoprotein(a)] of the [125I]T4 in the resolving gel. In HDL3, the major radioactive band was identified as apoA-I and contained 93-94% of the [125I]T4 in the resolving gel. Minor radioactive bands in both HDL2 and HDL3 were identified as apoA-II (17-18 kDa), apoA-II monomer (7-10 kDa), apoE (36-38 kDa), and apoAII-apoE heterodimer (46 kDa). In addition, HDL3 contained apoA-IV (43 kDa). Photoaffinity labeling of isolated apoA-IV and apoE showed that each protein interacted with [125I]T4. In both HDL2 and HDL3, photoaffinity labeling in the presence of unlabeled L-T4 (1-10 microM) showed inhibition, suggesting a Kd in the micromolar range. This inhibition varied among different apo bands of the same HDL2 or HDL3 preparation and among the same bands of different preparations. Labeling in the presence of heparin or other inhibitors of T4 binding to plasma proteins (furosemide, diclofenac, and mefenamic acid) showed that HDL2-associated apoA-I was more sensitive to inhibition than HDL3-associated apoA-I. In conclusion, 1) HDL2 and HDL3 carry T4 mainly through apoA-I and secondarily through apoA-II and apoE. The inter- and intrasubclass variations in T4 binding and sensitivity to inhibitors can be explained by the known heterogeneity of HDL particles and possible differences in conformation of the apo. The findings reported here, that apo other than apoA-I and apoB exhibit saturable binding of T4, suggest that thyroid hormone-lipoprotein interactions may have even wider physiological implications than previously appreciated.

Affinity Labels↗

PubMed1992

An evaluation of prototype school-based peer counseling program.

This study reports short-term outcome evaluation results of a school-based peer counseling (PRC) program as implemented by North Forsyth High School during January 1990-February 1991. The PRC program is evaluated in terms of: 1) the content of the program as evaluated by the PRC trainees; 2) the quality of the PRC instructor as perceived by these trainees; 3) several instrumental objectives deduced from the PRC training program; and 4) the degree to which the program was able to reach other students at North Forsyth during the time the PRC was in operation. In the absence of a control group, the treatment effect of the program is determined in terms of individual growth curve models. Through the multiple evaluation designs employed in this research, it has been learned that a significantly larger proportion of students in the PRC group had more favorable attitude toward the content of the PRC program when compared to the content of what they learned from their regular school curricula. Furthermore, a significantly larger proportion of students in the PRC program reported more favorable attitude toward their instructor than their regular school teachers. The PRC program was able to elicit an improvement of trainee self-esteem (p less than .01) and their social values (p less than .05) between pre and post of the Peer Training Evaluation Instrument. In terms of client access, 18.4 percent of the totality of potential clients at North Forsyth have been reached through sixty-one peer counselors sanctioned by the school.

Adolescent↗

PubMed1991

Clinical and laboratory findings in the oculocerebrorenal syndrome of Lowe, with special reference to growth and renal function.

BACKGROUND: The oculocerebrorenal syndrome of Lowe is an X-linked disorder whose clinical manifestations include congenital cataracts, mental retardation, and renal tubular dysfunction. We investigated growth, renal function, and serum chemistry values in patients with the oculocerebrorenal syndrome to determine the natural history of the disorder and its heterogeneity with respect to these characteristics. METHODS: Twenty-three patients with the oculocerebrorenal syndrome, ranging in age from 4 months to 31 years, were examined. Height was compared with bone age. Renal function was assessed by measurements of proteinuria, urinary volume, and fractional excretions of potassium, phosphate, carnitine, and amino acids. Creatinine clearance was determined as a measure of glomerular function. RESULTS: In the oculocerebrorenal syndrome, linear growth decreases after one year of age; bone age lies between chronologic age and height age. Renal dysfunction occurs in the first year of life, characterized by proteinuria (mean [+/- SD], 1.38 +/- 0.77 g of urinary protein per square meter of body-surface area per day; normal, less than or equal to 0.10), generalized aminoaciduria (mean, 686 +/- 505 mumol of urinary amino acid per kilogram of body weight per day; normal, 94 +/- 45), carnitine wasting (mean fractional excretion, 0.10 +/- 0.05; normal, 0.03 +/- 0.01), and phosphaturia progressing into the third decade. Urinary wasting of individual amino acids is milder than in cystinosis, and branched-chain amino acids are relatively spared. Reciprocal serum creatinine levels fall linearly with age, predicting renal failure in the fourth decade. Concentrations of the muscle enzymes creatine kinase, aspartate aminotransferase, and lactate dehydrogenase, as well as of total serum protein, serum alpha 2-globulin, and high-density lipoprotein cholesterol, are elevated. CONCLUSIONS: Renal glomerular deterioration is slowly progressive in the oculocerebrorenal syndrome. Renal tubular dysfunction begins early and persists; most patients require alkalinization therapy, and many benefit from supplemental potassium, phosphate, calcium, or carnitine. Serum enzyme elevations suggest muscle involvement in the oculocerebrorenal syndrome.

Adolescent↗