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J P Frommer

Publications and source records attributed to J P Frommer.

17 recordsLinked to original sources
PubMed1999

Relapsing membranous nephropathy. Response to therapy of relapses compared to that of the original disease.

BACKGROUND: Although controversial, treatment of membranous nephropathy appears to yield a reduction in the degree of proteinuria and conservation of renal function. METHODS: We report herein our experience with the treatment with steroids alone (group II, n = 13), or in combination with immunosuppressants (group III, n = 19) of patients with membranous nephropathy and the nephrotic syndrome, with a mean follow-up of 8.37 years. RESULTS: All patients underwent a first remission, with 24-hour urine protein excretion falling to 0.63 +/- 0.25 g in group II and 0.62 +/- 0.26 g in group III (p = NS) after 12.69 +/- 10.94 months of treatment in group II and 18.95 +/- 13.17 months in group III (p = NS). Three patients from group II (23%) and seven patients from group III (36.8%) experienced four and eight relapses, respectively (proteinuria in 24 h 4.0 +/- 0.80 g in group II relapsers and 4.4 +/- 0.87 in group III relapsers; p = NS). On treatment, all relapses remitted (second remission) after 7 +/- 6.93 months of therapy for group II and 8.6 +/- 6.70 months of treatment for group III (p = NS). Thereafter, no patients from group II, but 3 patients from group III (33.3%) had a second relapse. After treatment, all relapses remitted (third remission) in 3.3 +/- 1.53 months of therapy. CONCLUSIONS: These studies show that relapses, which occur in one-third of patients, respond favorably to treatment albeit remitting in approximately half the time, and that the duration of remission gets progressively longer in the later compared to the earlier remission.

Adult↗
PubMed1993

Medical nephrectomy: the last resort for intractable complications of the nephrotic syndrome.

The large protein excretion of nephrotic syndrome leads to severe hypoalbuminemia and massive edema. The ensuing hyperlipidemia may not respond to any treatment unless protein losses are corrected. Urinary excretion of clotting factors due to nonselective proteinuria explains, at least in part, the development of a procoagulable state. We report herein four cases of intractable nephrotic syndrome that required medical nephrectomy by bilateral embolization of renal arteries. This procedure, although unusually performed, is an important therapeutic option in selected patients with nephrotic syndrome.

Adult↗
PubMed1985

Juxtamedullary nephrons during acute metabolic alkalosis in the rat.

The renal handling of bicarbonate during acute metabolic alkalosis was examined in Munich-Wistar rats using micropuncture techniques. Group I received an acute bicarbonate load, and fractional delivery of total CO2 (tCO2) (FDtCO2) to the superficial late distal tubule (LD) was significantly lower than to the base of the papillary collecting duct (B) (18.4 +/- 1.7 vs. 22.9 +/- 1.5%; P less than 0.01), indicating net addition of bicarbonate between LD and B. When acutely bicarbonate-loaded rats had their deep nephrons destroyed with bromoethylamine hydrobromide (BEA) (group II), net addition of tCO2 between LD and B was abolished and net reabsorption uncovered (FDtCO2 LD: 28.0 +/- 3.6 vs. B: 17.5 +/- 2.5%; P less than 0.01). The infusion of amiloride (2.5 mg/kg body wt) to alkalotic rats treated with BEA (group III) completely inhibited distal bicarbonate reabsorption but did not reestablish addition (FDtCO2 LD: 27.6 +/- 1.6 vs. B: 26.1 +/- 3.7%; P = NS). The values obtained for sham-operated animals (group IV) were the same for group I. The patterns that were observed between LD and B were reproduced for the four groups of animals when FDtCO2 LD was compared with the fractional excretion of bicarbonate in the urine of the intact contralateral kidney. These studies suggest that juxtamedullary nephrons contribute a higher load of bicarbonate than superficial nephrons to the final urine during acute metabolic alkalosis in the rat.

Alkalosis↗
PubMed1985

Asymptomatic pericardial effusion in uremic patients: effect of long-term dialysis.

The present study was undertaken to determine the prevalence of asymptomatic pericardial effusion in a population with end-stage renal failure just prior to the initiation of chronic dialysis, and to determine the effect of long-term dialysis on these effusions. We prospectively studied 50 uremic patients with M-mode echocardiograms prior to initiation of chronic dialysis and followed 33 of these patients after 10 months of intense dialytic therapy. Predialysis effusion was present in 18/50 (36%) patients. Only 3/50 patients had clinical evidence of pericarditis (none of these individuals had an effusion). The incidence of clinical congestion and radiological evidence of volume overload was significantly higher in the patients with an asymptomatic pericardial effusion. Of these, the effusion disappeared on improved in 6 (43%), remained unchanged in 6 (43%), and worsened in 2 (14%). No patients developed new pericardise effusions during chronic dialysis. Changes in effusion size were related to changes in body weight between dialysis treatments (r = 0.39; p less than 0.05). Our data show that asymptomatic pericardial effusions are frequent in uremic patients prior to initiation of dialysis, the etiology of asymptomatic pericardial effusions in these patients appears to be related to volume overload, only 43% of the patients improved their effusions with chronic dialysis.

Adult↗
PubMed1985

Massive obesity and nephrotic proteinuria with a normal renal biopsy.

The association between massive obesity and nephrotic syndrome has been rarely reported. We herein describe a patient with massive obesity (209 kg) and nephrotic proteinuria who had a normal renal biopsy. The patient was initially polycythemic and had a supranormal creatinine clearance. After losing 89 kg, his hemoglobin and creatinine clearance returned to normal, and proteinuria decreased to 300 mg/24 h. We postulated that increases in glomerular hydrostatic pressure may result in local alterations of glomerular basement membrane sieving characteristics (biologic membrane thixotropy) with resultant nephrotic proteinuria. Prompt remission of proteinuria with weight loss supports a reversible glomerular hemodynamic alteration as a mechanism for the proteinuria of massive obesity.

Adult↗
PubMed1985

Effect of minor surgery on urinary flow and electrolyte excretion in the awake dog.

Spontaneous variations in urinary flow and electrolyte excretion are well known to occur both in man and in the non-human primate. Data on these spontaneous variations is scarce in the dog, an animal which is widely used in physiological investigations. Our study was designed to characterize the spontaneous pattern of renal hemodynamics, urine flow and electrolyte excretion in the awake dog both under conditions of minimal surgical stress (group I), and after routine preparatory surgery (group II). Our results show significant spontaneous variation for urine flow and urinary excretion of Na, K, Cl, HCO3, Ca, PO4 and Mg for both groups of dogs. Urinary excretion of Na, K, PO4 and Mg was significantly higher for group II than for group I (p less than 0.05). Glomerular filtration rate and effective renal plasma flow (estimated from the clearance of p-aminohippurate) were measured in group II and showed no spontaneous variation. Our study shows that there is diurnal urinary electrolyte excretion variation in the dog which is exaggerated by small changes in the experimental protocol. These variations need to be considered when evaluating experimental maneuvers that induce changes in the renal handling of electrolytes in the dog.

Animals↗
PubMed1984

Internephron heterogeneity for carbonic anhydrase-independent bicarbonate reabsorption in the rat.

The present experiments were designed to localize the sites of carbonic anhydrase-independent bicarbonate reabsorption in the rat kidney and to examine some of its mechanisms. Young Munich-Wistar rats were studied using standard cortical and papillary free-flow micropuncture techniques. Total CO2 (tCO2) was determined using microcalorimetry. In control rats both superficial and juxtamedullary proximal nephrons reabsorbed approximately 95% of the filtered load of bicarbonate. The administration of acetazolamide (20 mg/kg body weight [bw]/h) decreased proximal reabsorption to 65.6% of the filtered load in superficial nephrons (32% was reabsorbed by the proximal convoluted tubule while 31.7% was reabsorbed by the loop segment), and to 38.4% in juxtamedullary nephrons. Absolute reabsorption of bicarbonate was also significantly higher in superficial than in juxtamedullary nephrons after administration of acetazolamide (727 +/- 82 vs. 346 +/- 126 pmol/min; P less than 0.05). The infusion of amiloride (2.5 mg/kg bw/h) to acetazolamide-treated rats increased the fractional excretion of bicarbonate as compared with animals treated with acetazolamide alone (34.9 +/- 1.9 vs. 42.9 +/- 2.1%; P less than 0.01), and induced net addition of bicarbonate between the superficial early distal tubule and the final urine (34.8 +/- 3.0 vs. 42.9 +/- 2.1%; P less than 0.05). Amiloride at this dose did not affect proximal water or bicarbonate transport; our studies localize its site of action to the terminal nephron. Vasa recta (VR) plasma and loop of Henle (LH) tubular fluid tCO2 were determined in control and acetazolamide-treated rats in order to identify possible driving forces for carbonic anhydrase-independent bicarbonate reabsorption in the rat papilla. Control animals showed a tCO2 gradient favoring secretion (LH tCO2, 7.4 +/- 1.7 mM vs. VR tCO2, 19.1 +/- 2.3 mM; P less than 0.005). Acetazolamide administration reversed this chemical concentration gradient, inducing a driving force favoring reabsorption of bicarbonate (LH tCO2, 27.0 +/- 1.4 mM vs. VR tCO2, 20.4 +/- 1.0 mM; P less than 0.005). Our study shows that in addition to the superficial proximal convoluted tubule, the loop segment and the collecting duct show acetazolamide-insensitive bicarbonate reabsorption. No internephron heterogeneity for bicarbonate transport was found in controls. The infusion of acetazolamide, however, induced significant internephron heterogeneity for bicarbonate reabsorption, with superficial nephrons reabsorbing a higher fractional and absolute load of bicarbonate than juxtamedullary nephrons. We think that the net addition of bicarbonate induced by amiloride is secondary to inhibition of voltage-dependent, carbonic anhydrase-independent bicarbonate reabsorption at the level of the collecting duct, which uncovers a greater delivery of carbonate from deeper nephrons to the collecting duct. Finally, our results suggest that carbonic anhydrase-independent bicarbonate reabsorption is partly passive, driven by favorable chemical gradients in the papillary tubular structures, and partly voltage-dependent, in the collecting duct.

Absorption↗
PubMed1984

Carbonic anhydrase independent bicarbonate reabsorption in rats with chronic papillary necrosis.

The present study was designed to indirectly localize the tubular sites of carbonic anhydrase independent bicarbonate reabsorption in the rat. Papillary necrosis was induced in rats by intravenous administration of bromoethyleneamine hydrobromide (BEA) 6 weeks prior to the study, in order to assess the role of deep nephrons in this process. Acetazolamide alone, acetazolamide plus amiloride, and acetazolamide, amiloride plus furosemide were infused into rats with intact papillae (groups I, III, V) and rats with BEA-induced papillary necrosis (groups II, IV, VI). Our results show that chronic papillary necrosis does not alter carbonic anhydrase independent bicarbonate reabsorption, since the fractional excretion of bicarbonate (FEHCO3) was not significantly higher when acetazolamide was infused into animals with BEA-induced papillary necrosis as compared to those rats with intact papillae (FEHCO3 group I vs. group II: NS). The addition of amiloride hydrochloride, a blocker of distal acidification at the administered doses, increased FEHCO3 significantly in both, animals with intact papillae and those with papillary necrosis, to a similar degree. The addition of furosemide to acetazolamide and amiloride further induced a significant increase in FEHCO3 only in the group of animals with papillary necrosis (FEHCO3 group V 43.0 +/- 2.9% vs. group VI 52.1 +/- 0.9%; p less than 0.05). It appears from our study that deeper nephrons and papillary structures are not indispensable for carbonic anhydrase independent bicarbonate reabsorption in the rat on a chronic basis. The cortical collecting duct appears to have a significant capacity to reabsorb bicarbonate independent of carbonic anhydrase which can be blocked by amiloride.(ABSTRACT TRUNCATED AT 250 WORDS)

Absorption↗
PubMed1984

Effects of head-out water immersion on the urinary excretion of phosphate, calcium and magnesium in the awake dog.

The present study was undertaken to define the effects of heat-out water immersion on the urinary excretion of phosphate (UPO4V), calcium (UCaV), and magnesium (UMgV) in the awake dog. 53 dogs were divided into three groups: group I, time-control, from 10 a.m. to 4 p.m.; group II, immersion for 2 h, studied from 10 a.m. to 4 p.m., and group III, immersion for 2 h, studied from 4 p.m. to 10 p.m. Our results show that head-out water immersion did not alter the spontaneous pattern of UPO4V. When immersion was performed from 1 p.m. to 3. p.m. (group II), it had no effect on UCaV but induced a significant increase in UMgV although fractional excretion of Mg (FEMg) remained unchanged. When immersion was performed from 7 p.m. to 9 p.m. (group III), however, both UCaV and UMgV increased significantly. FECa also increased significantly in this group but FEMg again remained unchanged. The changes in UCaV were dissociated with UNaV. Changes in plasma PO4 (PPO4) and arterial pH were unrelated to changes in UCaV or UPO4V. Our findings show that head-out water immersion induces significant increases in UCaV and UMgV by mechanisms which are independent of parathyroid hormone (PTH) or acid base changes. The rise in UMgV seems to be related to an increase in the filtered load, while the increases in UCaV are secondary to changes in the renal tubular handling of calcium. Thus, under these experimental circumstances, Ca and Mg reabsorption seem to occur via different distal tubular pathways.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1983

Cardiopulmonary toxicity in patients with breast carcinoma during plasma perfusion over immobilized protein A. Pathophysiology of reaction and attenuating methods.

Tumoricidal reactions in dogs with spontaneous breast carcinoma occur after perfusion of plasma over protein A derived from Staphylococcus aureus and immobilized in collodion charcoal. When this treatment was extended to humans with breast cancer, hemodynamic and physiologic changes were noted. The evolution and spectrum of these reactions were evaluated during 47 plasma infusions in five patients. Initial treatment conditions consisting of rapid perfusion of plasma over high quantities of immobilized protein A were employed for 12 treatments in two patients. Within 30 minutes after treatments were begun, mean blood pressure, systemic vascular resistance, and stroke volume increased, as did heart rate, cardiac output, and rectal temperature; however, mean pulmonary artery pressure and total pulmonary resistance did not change. At 90 minutes, hypotension developed (lowest mean blood pressure was 59 +/- 14 mm Hg) that was associated with a decrease in systemic vascular resistance and total pulmonary resistance (536 +/- 66 and 146 +/- 44 dynes . second . cm-5, respectively). Cardiac output increased, tachycardia developed, stroke volume decreased, and rectal temperature increased. During the hypotensive phase, values of creatinine clearance and fractional excretion of sodium diminished. Noncardiogenic pulmonary edema appeared occasionally, with bronchospasm noted once. No hemodynamic changes were seen when saline solution was passaged over protein A immobilized in collodion charcoal or when autologous plasma was given without passage over protein A immobilized in collodion charcoal. Treatment conditions were modified by diminishing protein A quantity and plasma volume and slowing plasma perfusion rate, which resulted in significant attenuation of all cardiopulmonary responses. This report, then, defines for the first time the physiologic basis of the cardiopulmonary toxicity in humans after plasma perfusion over immobilized protein A.

Breast Neoplasms↗
PubMed1983

Lactic acidosis.

Explore the source record for details and available documents.

Acidosis↗
PubMed1982

Rapid correction of severe hyponatremia with intravenous hypertonic saline solution.

Severe hyponatremia with hypoosmolality carries a high morbidity and mortality and constitutes a life-threatening emergency. We report seen cases of severe hyponatremia (serum sodium concentration 99.7 +/- 3.0 meg/liter) (mean +/- SEM) with hypoosmolality (212 +/- i mOsm/kg water) that presented with severe neurologic complications. Serum sodium concentration was corrected in 13.3 +/- 2.2 hours to mildly hyponatremic levels (serum sodium concentration 128.3 +/- 1.6 meq/liter). The rate of correction of serum sodium concentration was 2.4 +/- 0.5 meq!liter/hr. This was achieved by the intravenous administration of 3 percent hypertonic saline solution (687 +/- 43 meq sodium chloride) and furosemide or by hemodialysis where indicated. No complications occurred from treatment and all of our patients recovered without neurologic sequelae. Early diagnosis and rapid correction of serum sodium concentration appear to reduce the significant morbidity and mortality of severe hyponatremia.

Adult↗
PubMed1982

Free-flow micropuncture study of renal urate transport in the Munich-Wistar rat.

In order to determine the nephron sites of urate reabsorption, the fractional rates of delivery of urate to specific segments of the superficial and deep nephrons were determined by the free-flow micropuncture technique in the Munich-Wistar rat. In nondiuretic control animals, the fractional delivery of urate to the late proximal tubule (34.1 +/- 3.6%), distal tubule (39.0 +/- 6.2%), base (32.6 +/- 3.2%), and tip (32.3 +/- 5.6%) of the papillary collecting duct were not different from one another. In animals in which the extracellular fluid volume was expanded with isotonic saline and in animals infused with the uricosuric diuretic MK-196, the fractional rates of urate delivery to any given nephron segment were significantly higher than in controls. There were no significant differences in either group, however, in the rates of delivery of urate to the specific nephron sites sampled. These studies indicate that urate absorption occurs primarily in the proximal convoluted tubule, but provide no evidence for nephron heterogeneity for urate transport. Expansion of the extracellular fluid volume and the infusion of MK-196 resulted in a higher fractional excretion of urate.

Absorption↗
PubMedDate not supplied

Intratubular microinjection study of gentamicin transport in the rat.

The intratubular microinjection technique was used to determine the absorptive flux of radioactive gentamicin the rat. Microinjection into the early tubule and late proximal tubule resulted in recoveries of proximal 66.6 +/- 3.6% and 80.4 +/- 3.4%, respectively. Recoveries after microinjection into the distal convoluted tubule averaged 101.0 +/- 4.3%. The addition of tobramycin, phospholipase A, spermine or probenecid to the microinjection solution inhibited gentamicin absorption. These studies indicate that an absorptive flux of gentamicin is present in the superficial proximal tubule and at a nephron site or sites between the superficial proximal and distal tubules. Gentamicin absorption is mediated by a phospholipid carrier with specificity for polyamines and other aminoglycosides. The presence of probenecid in the perfusion solution inhibited the tubular absorption of gentamicin.

Absorption↗