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Biomedical subjects

D Modai

Publications and source records attributed to D Modai.

At least 37 records · Page 2Linked to original sources
PubMed1990

Induction of suppressor cell activity in normal peripheral blood mononuclear cells by sera from predialytic uremic patients.

Normal peripheral blood mononuclear cells (PBMC) were primed with sera from 22 predialytic uremic patients, normal sera, concanavalin A, or both. Their suppressive activity was subsequently tested on fresh phytohemagglutinin-stimulated allogeneic responders (i.e., genetically unrelated to either primed cell or sera donors). Uremic serum induced suppressor cell activity in the normal PBMC. No correlation was found between serum urea/creatinine levels and their effects on suppressor cell activity. The induced activity, expressed as percent suppression, was similar to that induced by concanavalin A. In PBMC primed with both concanavalin A and uremic serum, an additive suppressive effect was evident. The suppressor subset(s) induced by uremic serum proved to belong to adherent cell population. Addition of indomethacin or catalase to responder systems did not abolish the suppressive effects, thus suggesting a mechanism of action other than prostaglandin or hydrogen peroxide release.

Adult↗
PubMed1990

Dual challenge for glomerular damage in mice: uninephrectomy and repetitive pregnancies.

We examined the effects of unilateral nephrectomy (UNx) and repetitive pregnancies (RP) on glomerular damage and blood pressure in mice. Four groups of 10 female mice, 7 weeks old, underwent sham nephrectomy (SV) alone, sham nephrectomy and six pregnancies (SP), right nephrectomy alone (NV) and right nephrectomy followed by six repetitive pregnancies (NP). UNx resulted in a significant elevation of serum creatinine up to 11 weeks. In all animals pregnancy was associated with a temporary decrease in serum creatinine except at termination of the 6th pregnancy in group NP. UNx and RP did not result in an increase in protein excretion. UNx in both virgin and pregnant mice resulted in blood pressure elevation without any renal histological abnormalities by the end of the 6th pregnancy. We conclude that at least up to the end of the 3rd pregnancy, gestation was associated with augmentation in function of a single kidney. This effect was lost by the end of the 6th pregnancy. Multiple repetitive pregnancies in uninephrectomized animals entailed renal functional deterioration and a rise in blood pressure without renal histological abnormalities on light microscopy.

Animals↗
PubMed1989

Increased concanavalin A-induced suppressor cell activity in humans with occupational lead exposure.

E-rosette-forming cells (E-RFC), mitogen-induced blast transformation, OKT4+, OKT8+ cells, and their ratio were found to be normal in 10 subjects chronically exposed to lead with blood levels of 40-51 micrograms%. However, concanavalin A (Con A)-induced suppressor cell activity (SCA) in these subjects was significantly greater than in normal matched controls. The clinical relevance of this observation is not clear, but it may have some bearing on the various immunologic defects described in lead exposure.

Adult↗
PubMed1989

Uninephrectomy and repetitive pregnancies in mice: a combined stimulus for renal hypertrophy.

Three hundred 7-week-old Beit Dagan female mice underwent right nephrectomy or sham operation, and either remained virgin or were exposed to six repetitive pregnancies. Fractional kidney weight, dry weight and protein content were determined at ages 9, 10, 11, 17 and 26 weeks corresponding to the ends of the first, second and third trimester of the first pregnancy and completion of the third and sixth pregnancies respectively. In addition histological sections were evaluated morphologically and morphometrically. Renal dry weight and protein content per kidney increased abruptly to maximal values a week after nephrectomy and remained stable thereafter. Repetitive pregnancies were associated with progressive increments in both parameters. The effects of unilateral nephrectomy and repetitive pregnancy were additive. Following unilateral nephrectomy or pregnancy the number of glomeruli per field, as well as fractional glomerular area, increased more rapidly than in sham-operated virgin controls. However, the maximal glomerular number or fractional area attained did not differ from control values. We conclude that (a) in 8-week-old mice pregnancy is associated with renal cell hypertrophy; (b) repetitive pregnancies in these animals produce progressive augmentation in both renal dry weight and protein content; (c) the effects of repetitive pregnancy and unilateral nephrectomy on renal cell hypertrophy are additive; (d) this would indicate that neither manoeuvre exhausts maximal renal capacity for cell hypertrophy, and would suggest some possibilities for the underlying mechanisms.

Animals↗
PubMed1989

Cimetidine-related cardiac conduction disturbances and confusion.

A 70-year-old woman free of renal or hepatic dysfunction developed reversible mental confusion, sinus bradycardia, and extreme QT interval prolongation following initiation of intravenous cimetidine 1200 mg daily. The association of mental confusion with cardiac conduction impairment in a single patient in the context of cimetidine toxicity is highly unusual. We review this and other reports on potentially fatal cimetidine-related cardiac conduction disturbances to suggest that in patients at risk, in addition to reducing cimetidine dosage, electrocardiogram (ECG) follow-up is indicated to identify dangerous bradycardia and QT interval prolongation.

Aged↗
PubMed1989

Acute resin phenol-formaldehyde intoxication. A life threatening occupational hazard.

1. A 38-year-old previously healthy worker accidentally spilled phenol-formaldehyde resin over a large area of his skin. 2. Several days later he was hospitalized with extensive necrotic skin lesions, fever, hypertension, adult respiratory distress syndrome (ARDS), proteinuria and renal functional impairment. 3. All symptoms improved progressively and eventually disappeared. 4. We propose that toxic materials originating from the necrotic skin lesions and the continued facilitated absorption of the resin and/or its components via the skin lesions were the main factors responsible for this alarming multisystem involvement. 5. Workers handling this material should be instructed to take appropriate precautions and physicians should be alerted to the potential pathophysiological consequences.

Adult↗
PubMed1989

Rhabdomyolysis and acute renal failure induced by paraphenylenediamine.

1. We present a 40-year-old healthy man who developed a typical clinical picture of rhabdomyolysis following the administration of paraphenylenediamine by a witchdoctor as a pain killer. 2. Two groups of 15 mice were given paraphenylenediamine 70 mg/kg and 35 mg/kg respectively. Biochemical and histological findings of rhabdomyolysis developed in both groups, without kidney damage. 3. Paraphenylenediamine may cause rhabdomyolysis resulting in acute renal failure in humans. In mice, however, it produces rhabdomyolysis, but the kidneys are not affected.

Acute Kidney Injury↗
PubMed1988

The renotrophic factor, a persistent stimulus that crosses the placenta in mice.

1. Twenty 7-week female mice underwent right nephrectomy and twenty others were sham operated. A week later all animals were made pregnant. Pregnancy was repeated five more times consecutively and various renal parameters were assessed in the pups. 2. Fractional fresh kidney weight (relative to body weight) was significantly increased in the pups of nephrectomized mothers while percentage renal water and protein content expressed as mg/g kidney weight were not statistically different in the two groups of pups. Thus dry kidney weight and amount of protein per kidney were increased in the experimental group. This was true for the newborns of all six pregnancies. 3. Renal morphometric studies performed in newborns of first pregnancies showed that the mean number of glomeruli per microscopic field, mean fractional cumulative glomerular area (relative to microscopic field area) and the mean number of cells per glomerulus were significantly greater in the experimental group. Mean glomerular radius was not statistically different in the two groups. 4. The results indicate that: (1) the renotrophic factor(s) crosses the placenta in mice; (2) its activity in maternal circulation following uninephrectomy is sustained for a relatively long period; and (3) fetal response to enhanced maternal renotrophin stimulation consists of increased renal dry weight and renal protein, formation of super-physiological numbers of glomeruli and cellular hyperplasia of the glomeruli.

Alanine Transaminase↗
PubMed1988

Effect of levamisole on chemotaxis of granulocytes from uremic patients.

Uremic granulocyte chemotaxis was assessed in the presence of four different concentrations of levamisole. Chemotactic responsiveness of uremic granulocytes was significantly decreased compared to normal, both in the absence of levamisole and with all levamisole concentrations tested. However, with 10(-3) and 10(-4) M levamisole concentrations, uremic granulocyte chemotaxis was similar to that of normal granulocytes without levamisole. Defective chemotactic activity of granulocytes may play a role in the increased susceptibility of uremic patients to infections. Pharmacological correction of this defect may improve the patients' ability to cope with infections.

Adult↗
PubMed1988

1,25-Dihydroxyvitamin D-induced suppressor cells in uremic versus normal lymphocytes.

1,25-Dihydroxyvitamin D3 (DHD) has been shown to suppress mitogen-induced blast transformation. This inhibition is abolished by prior elimination of adherent cells. Chronic renal failure is an immunodeficiency state on the one hand and is associated with abnormalities in vitamin D metabolism on the other. The effect of DHD on the induction of suppressor cells in uremic vs. normal peripheral blood mononuclear cells was investigated. Study groups included 16 chronically uremic patients and 16 age- and sex-matched controls. DHD induced suppressor cell activity in normal lymphocytes. However, no suppressor cell activity was observed in lymphocytes from the uremic patients preincubated with DHD. The origin of the responder cells (normal or uremic) did not affect the outcome. The results would suggest that monocyte-adherent suppressor cells from uremic subjects are either incapable of binding DHD or fail to mount a normal post-receptor intracellular chain of events culminating in suppressor activity.

Adult↗
PubMed1988

Autosomal dominant carpal tunnel syndrome in a Karaite family.

A clinical examination and a history of 64 members belonging to four generations of a Karaite kindred revealed 11 patients with carpal tunnel syndrome (CTS). Bilateral involvement and early age of onset are salient features. The mutation may be traced in four generations. Hereditary primary CTS may be more prevalent than hitherto suspected.

Adult↗
PubMed1988

Frozen saphenous vein allografts for constructing vascular access for hemodialysis.

Frozen saphenous vein allografts were used in seven patients to construct vascular access for hemodialysis. In five patients the allografts connected the brachial artery to the axillary vein, and in two, the radial artery to the basilic vein. Five allografts functioned for periods varying from 6 to 20 months, one is still functioning after 3 years, and one graft occluded immediately following surgery. The availability of this biological material, the ease of its preparation, the very low cost, and the satisfactory graft survival, call for further evaluation of this method for complex vascular access problems in patients on chronic hemodialysis.

Adult↗
PubMed1987

"Idiopathic" hypercalciuria and hereditary hypophosphatemic rickets. Two phenotypical expressions of a common genetic defect.

Among 59 closely related members of one Bedouin tribe, we identified 9 who had the characteristic features of hereditary hypophosphatemic rickets with hypercalciuria (HHRH). We found "idiopathic" hypercalciuria in 21 of the 50 asymptomatic members. The biochemical abnormalities observed in these 21 subjects were qualitatively similar to those in the 9 with HHRH, but were quantitatively milder. The urinary calcium concentration was 0.43 +/- 0.14 mg per milligram of creatinine (mean +/- SD) in the patients with HHRH, 0.34 +/- 0.07 in the subjects with idiopathic hypercalciuria, and 0.14 +/- 0.05 in normal subjects from the same tribe. Tubular reabsorption of phosphorus and serum phosphorus concentrations were 3.0 and 4.3 SD units below the age-related mean, respectively, in HHRH, and 1.1 SD units below the normal mean for both variables in idiopathic hypercalciuria. Mean serum levels of 1,25-dihydroxyvitamin D (1,25-(OH)2D) were 303 pg per milliliter in HHRH and 145 pg per milliliter in idiopathic hypercalciuria (upper normal limit, 110). We conclude that the subjects with hypercalciuria and the patients with HHRH shared a hereditary renal phosphate leak that led to hypophosphatemia, elevated serum concentrations of 1,25-(OH)2D, increased intestinal calcium absorption, and hypercalciuria. The magnitude of the hypophosphatemia, which regulates 1,25-(OH)2D levels, appears to determine which subjects will have hypercalciuria alone and which will also have bone disease.

Adolescent↗
PubMed1987

Hydrochlorothiazide-amiloride causes excessive urinary zinc excretion.

Serum zinc levels and urinary zinc excretion were compared in 15 patients with essential hypertension taking chronically a combination of hydrochlorothiazide and amiloride as monotherapy, eight patients maintained with hydrochlorothiazide alone, and eight control subjects. Serum zinc values were statistically comparable in all three groups. However, urinary zinc excretion was abnormally elevated in the two patient groups. In the dosage used, amiloride did not have a zinc-sparing effect.

Adult↗
PubMed1987

Barium appendicitis: fact or fancy? Report of a case and review of the literature.

Whether barium retained in the appendix can be a cause of acute appendicitis is debatable. We describe a 40-year-old man who developed nonspecific right abdominal pain 7 weeks after a barium enema, which proved to be normal. On abdominal film a distended appendix containing barium was seen, and at laparotomy acute appendicitis was present. Thus far, 26 cases of "barium appendicitis" have been reported. On the basis of the relevant literature and the cases collected, it is appropriate to draw the following conclusions: 1) With present knowledge it is not possible to state whether retained barium plays any etiologic role in the development of subsequent uncomplicated acute appendicitis. 2) If a later appendicitis does supervene, it carries a high risk of being complicated; barium seems to be responsible for the complication. 3) The longer the interval between the barium study and the subsequent appearance of acute appendicitis, the higher will be the risk of complications.

Acute Disease↗