Biomedical subjects

G A Beathard

Publications and source records attributed to G A Beathard.

At least 19 recordsLinked to original sources

PubMed1992

Percutaneous transvenous angioplasty in the treatment of vascular access stenosis.

This study was undertaken to evaluate percutaneous transvenous angioplasty (PTVA) for the treatment of all types of vascular access stenosis in a large population of dialysis patients. Stenoses were identified by venography in patients who met a set of clinical criteria indicating the need for evaluation. The lesions were classified by location and type. Data were collected prospectively and analyzed separately for each lesion type. A total of 536 PTVA procedures was performed in 285 patients. This included 107 cases of long venous stenosis (> 6 cm) and 149 cases of mid-graft stenosis. In the total group, an initial success rate of 94% was obtained (80% or greater dilatation). A decrease in VPm (venous pressure measured on dialysis) of 35.9%, 32.4%, and 22.6% was seen at one week, one month, and three months, respectively. At 90 days, 180 days, and 360 days 90.6%, 61.3%, and 38.2%, respectively, of the treated grafts were continuing to be patent and functional with no need for repeat PTVA treatment. Repeat treatments for recurrent lesions were as successful as the initial treatment. It is concluded that vascular access stenosis can be easily diagnosed and that all categories of stenotic lesion can be effectively treated with PTVA.

Angioplasty, Balloon↗

PubMed1977

Development of the characteristic ultrastructural lesion of hereditary nephritis during the course of the disease.

The diagnosis of hereditary nephritis in the absence of a clear family history or the presence of characteristic ancillary abnormalities is difficult, but it has considerable prognostic importance. The recent recognition of an ultrastructural lesion characteristic of this disease, although not present in all families, is of considerable value. In this report we describe a kindred with the lesion-associated disease that differs from those previously described in that the lesion developed during the course of the disease, was not present in all affected members and appeared to be the result of paternal transmission.

Adolescent↗

PubMed1977

Nephronophthisis. Renal function and histologic studies in a family.

Nephronophthisis (previously described as familial juvenile nephronophthisis and medullary cystic disease) is characterized by insidious renal failure, its main features being increased urinary sodium loss, pitressin-resistant hypotomic polyuria, polydipsia, normal urine sediment and absence of hypertension. Renal function and histologic studies were performed in a family in which two siblings had this disorder, while the parents and two other siblings appeared clinically normal. Both parents demonstrated a moderate impairment of maximum urinary concentration. The values for tubular free water reabsorption (TcH2O) were relativley normal in the parents and the healthy siblings. One of the index patients showed only minimal sodium wasting even though he had hyposthenuria, thus suggesting an involvement of the collecting ducts in the early stage of neophronophthisis. No evidence of proximal tubular dysfunction was found. Although the light-microscopic examination of renal biopsies from the parents and the healthy siblings was unremarkable, electron microscopy revealed probable abnormalities in all four. An autosomal recessive mode of inheritance is, therefore, suggested in this family. The etiology of nephronophthisis is obscure but a likely possibility is that the renal damage results from an inborn metabolic error.

Adolescent↗

PubMed1976

The nephrotic syndrome associated with neoplasia: an unusual paraneoplastic syndrome. Report of a case and review of the literature.

The nephrotic syndrome complicating malignancy in the absence of renal vein thrombosis, amyloid or neoplastic infiltration of the kidney is an unusual occurrence. A case of diffuse, well differentiated, lymphocytic lymphoma and lipoid nephrosis documented by light microscopy, electron microscopy and immunofluorescent studies is reported. A review of the literature revealed 76 case reports in which the nephrotic syndrome was associated with neoplasia. The most frequently associated neoplasms are Hodgkin's disease, various carcinomas, nonHodgkin's lymphoma and leukemia in descending order. The most frequent renal lesion in patients with the nephrotic syndrome associated with various carcinomas is membranous glomerulonephritis (81 per cent) as opposed to patients with lymphomas or leukemias who have predominantly lipoid nephrosis (60 per cent). The evidence is reviewed suggesting that the lesions in membranous nephropathy are immunologically mediated by tumor or viral antigen-antibody complexes and in lipoid nephrosis perhaps by a defect in t-lymphocyte function.

Aged↗

PubMed1975

B-lymphocytosis factor in human plasma.

Patients with acute thermal burns experience an increase of serum immunoglobulins associated with marked B-lymphocytosis during the recovery phase from the burn injury. This study was performed to delineate humoral factors which may induce the B-lymphocytosis in such patients. Plasma samples were obtained serially from 14 adult patients and 14 adult controls. One-half ml of plasma was injected intraperitoneally into C3H/He male mice, and absolute numbers of surface immunoglobulin-bearing cells in the mouse peripheral blood were counted. Fractionation of plasma samples was performed. The biologically active plasma fraction, tentatively termed B-lymphocytosis factor (BLF), was cultured with normal human peripheral blood lymphocytes to determine in vitro lymphocyte transformation. The solubility of 125I-labelled BLF in various organic solvents was examined. Plasma obtained from burned patients induced a marked increase of IgG, IgA, and IgM-bearing cells in the peripheral blood of mice within 3 hours after injection. The B-lymphocytosis activity of normal plasma was not significant. The molecular weight of BLF was estimated to be close to that of ribonuclease A (M.W. 13,400). Transformation of normal human peripheral blood lymphocytes was observed when cultured with BLF. 125I-labelled BLF was not soluble in organic solvents. These data suggest that BLF is not a lipopolysaccharide, and plays a role in regulation of B-lymphocyte levels in burned patients.

Adolescent↗

PubMed1975

Smooth muscle in lymph node capsule and trabeculae.

This study focuses on the confusion in existing literature concerning the presence of smooth muscle in the capsule and trabeculae of lymph nodes. Human and bovine nodes from several anatomical areas and several individuals of each species were examined by conventional light, electron and fluorescence microscopy. Smooth muscle cells, independent of blood vessels, were demonstrated in the trabeculae and capsules of lymph nodes of both species examined by all three techniques. The need for further study on the function of these cells is indicated.

Animals↗

PubMed1975

Oubain-sensitive adenosine triphosphatase from human kidneys.

Adenosine triphosphatase (ATPase) was studied in tissue homogenates and subcellular fractions derived from human cadaver kidneys maintained in an organ preservation unit for transplantation. The activity of ouabain-sensitive ATPase was highest in the medulla, intermediate in the cortex and lowest in the papilla. The cortical enzyme activity diminished with time during maintenance perfusion of the kidneys. Similar concentrations of K+, Na+, Mg++, ATP and MgATP were required for half-maximal rates of ouabain-sensitive ATPase activity from the cortex or the medulla. The sensitivity of the enzyme to ouabain from both parts of the kidney was similar. K+ antagonized inhibition of the enzyme by ouabain. Chlormerodrin, mersalyl, mercaptomerin and ethacrynic acid were inhibitors of the enzyme.

Adenosine Triphosphatases↗

PubMed1974