The stone clinic effect in patients with idiopathic calcium urolithiasis

The "stone clinic effect" refers to the effect of encouraging a high intake of fluid and avoiding dietary excesses on stone formation and growth in patients with urolithiasis. To determine the extent of this effect we reviewed the clinical courses of 108 patients with idiopathic calcium urolithiasis and indeterminant metabolic activity. There was no evidence of stone growth or new stone formation (metabolic inactivity) after a mean followup of 62.6 months in 63 of the 108 patients (58.3 per cent), including 12 of 17 (70.6 per cent) with hypercalciuria and 7 of 15 (46.7 per cent) with hyperuricosuria. Comparison of initial and followup 24-hour urine volumes demonstrated a significant increase in patients who were metabolically inactive at followup (p less than 0.0005), while no increase was detected in patients who were metabolically active at followup. We recommend that specific drug therapy should not be given to patients with idiopathic calcium urolithiasis until the stone clinic effect has been evaluated.

Hemolytic disease of the newborn following maternal self-injection of blood

A teenage primigravida with no prior history of transfusion presented with anti-D, anti-C, and anti-E in her serum and subsequently developed anti-Fya. The infant had hemolytic disease of the newborn. The antibodies were provoked by the girl's self-injection of her partner's blood for emotional gratification. Clinicians and transfusion services should be aware that hemolytic disease of the newborn in a first pregnancy can be caused by self-inflicted maternal immunization. Close communication between clinicians and transfusion service is emphasized.

beta-Adrenergic blocking agents. 23. 1-[Substituted-amido)phenoxy]-3-[[(substituted-amido)alkyl]amino] propan-2-ols

The synthesis of a series of 1-phenoxy-3-[(amidoalkyl)amino]propan-2-ols, in which the phenoxy ring is variously substituted with ortho and para amidic moieties, is described. Several of the compounds have beta-blocking potency comparable to that of propranolol and cardioselectivity similar to that of practolol, when given intravenously to anesthetized cats. In contrast to previous findings with cardioselective beta blockers, both ortho and para substitution give variable degrees of cardioselectivity. Potency, however, is favored by ortho substitution.

Sulphate conjugation of p-hydroxytriamterene by platelet phenol sulphotransferase: assay conditions and correlation with metabolism in man

1 Sulphate conjugation catalyzed by phenol sulphotransferase (PST) is an important pathway in the metabolism of many drugs including triamterene. Variations in PST activity in an easily obtained tissue such as the platelet might reflect individual differences in the sulphate conjugation in other organs and tissues. Human platelets contain at least two forms of PST, a thermolabile (TL) form for which dopamine is a substrate and a thermostable (TS) form for which low concentrations of p-nitrophenol serve as a substrate. 2 p-OH-triamterene, the major metabolite of triamterene, is conjugated with sulphate in vivo. p-OH-triamterene was a substrate for platelet PST with an apparent Michaelis-Menten value of 26 microM. Thermal stability studies indicated that p-OH-triamterene was a substrate for only the TS form of platelet PST. 3 When platelet homogenates from 29 individual subjects were tested, there was a significant correlation between PST activities measured with 4 microM p-nitrophenol and with p-OH-triamterene (r = 0.985, P less than 0.0001) but not between activities measured with dopamine and with p-OH-triamterene (r = 0.023, P greater than 0.2). These results confirmed that p-OH-triamterene was a substrate for only the TS form of human platelet PST. 4 The same 29 subjects were treated with 1 mg/kg of triamterene orally. 24-h urinary excretions of triamterene, p-OH-triamterene and p-OH-triamterene sulphate averaged 15.3%, 6.3% and 78.4%, respectively, of the total of triamterene plus measured metabolites excreted. The excretion of triamterene plus the two metabolites averaged 43.1 +/- 2.6% (mean +/- s.e. mean) of the ingested dose. There was not a significant correlation between the proportion of p-OH-triamterene excreted as sulphate conjugate and the activities of either the TS or TL forms of platelet PST activity.

Potentiation of butylated hydroxytoluene-induced acute lung damage by oxygen. Cell kinetics and collagen metabolism

Changes in cell proliferation and in collagen synthesis were studied in young adult male BALB/c mice injected intraperitoneally with 400 mg/kg of butylated hydroxytoluene (BHT) in corn oil or corn oil alone and immediately exposed to 70% oxygen or air for 6 days. Mice received [3H]thymidine either as a single injection 90 min before being killed or as a continual infusion via an osmotic minipump. Autoradiography was done 2 to 14 days after BHT injection, and cell kinetic studies were performed. In a similar experiment, mice were injected intraperitoneally with [3H]proline 3 h before being killed, and type l/type III collagen ratio in newly synthesized lung collagen was determined. We found that exposure to 70% oxygen immediately after the administration of BHT initially delayed the epithelial cell proliferation and the decrease in the percentage of newly synthesized type III collagen that occurred after BHT alone. Once the animals were removed from oxygen there was a compensatory burst of cell proliferation and a precipitous drop in the percentage of newly synthesized type III collagen. The proliferating cell population after removal from oxygen was primarily interstitial and not epithelial. When exposure to oxygen was delayed, cell proliferation was similar to that seen after BHT injection alone.

beta-adrenergic blocking agents. 24. Heterocyclic substituted 1-(aryloxy)-3-[[(amido)alkyl]amino]propan-2-ols

The synthesis of a series of 1-(aryloxy)-3-[[(amido)alkyl]amino] propan-2-ols where either the aryl moiety is heterocyclic or the amidic group is substituted by a heterocyclic moiety is described. Several of the compounds were more potent than propranolol when given intravenously to anesthetized rats. In contrast to previous findings with beta-blockers based on heterocyclic moieties and with either an isopropylamino or tert-butylamino substituent on the side chain, several compounds proved to be cardioselective when further examined in anesthetized cats. The detailed structure-activity relationships shown by this series of compounds are discussed.

Beta-adrenergic blocking agents. 22. 1-Phenoxy-3-[[(substituted-amido) alkyl]amino]-2-propanols

The synthesis of a series of 1-phenoxy-3-[[(substituted-amido)alkyl]amino]-2-propanols is described. Many of the compounds are more potent than propanolol as beta blockers, while having cardioselectivity comparable to that of practolol, when given intravenously to anesthetized cats. The structure-activity relationships shown by this series of compounds provide further evidence that the addition of substituents to the alkylamino moeity of a beta blocker can confer cardioselectivity and that amidic substituents are remarkably effective.

Rheumatoid arthritis: from Rubens to restriction maps

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Triamterene urolithiasis: solubility, pk, effect on crystal formation, and matrix binding of triamterene and its metabolites

The commonly used diuretic Tri and its metabolites have been identified recently as major components of some kidney stones. We have carried out basic physical chemical studies to determine the mechanism of Tri incorporation into kidney stones. The solubility and pK of Tri and its major metabolites, Tri-OH and the Tri-So4, have been determined at 37 C in 0.15 M NaCl. The effect of Tri and its metabolites on crystal formation has been measured in the calcium oxalate monohydrate, hydroxyapatite, and uric acid crystal systems. Tri and its metabolites do not promote crystal nucleation, growth, or aggregation in any of these crystal systems and are not incorporated as these crystals form. We can demonstrate binding of Tri and its metabolites to the protein matrix isolated from kidney stones. These data suggest that Tri and its metabolites to the protein matrix isolated from kidney stones. These data suggest that Tri and its metabolites do not promote the formation of kidney stones but rather become incorporated into existing stones or stone nidi by binding to the protein matrix found in all kidney stones.

Moulting Sequences in the Development of Tail Plumage of the Superb Lyrebird, Menura novaehollandiae

The tail of the superb lyrebird consists of 12 filamentary feathers flanked by two broad lyrates, distinguished by their pigmented bars, and two fine wire-like medians in the middle. The female's tail consists of 12 plain broadfeathers between two lyrates, which are less pigmented than those of the male, and two plain broad medians, all feathers being shorter than those of the male. The tail of the 1st-year lyrebird resembles that of the female, but the lyrates are shorter and only faintly barred. The transformation of the immature tail into the mature form proceeds through a series of annual moults, extending over 6-8 years, during which the three types of feathers change their respective forms. Each bird follows its own course and each follicle acts independently of the others during maturation, but becomes coordinated as the bird approaches maturity. Dimensions and weights are given for the various types of feathers and for complete tails, which are described and illustrated, along with moulting schedules for several birds. Data are given for the total rate of production of keratin in the entire tails and for individual follicles for birds of different ages. The role of the endocrine system in the maturation process is discussed.

Renal surgery can "precipitate" stone disease in mild asymptomatic primary hyperparathyroidism

We report on a patient in whom 3 large renal calculi formed within 12 weeks after pyeloplasty. Subsequently, a parathyroid adenoma was found. This report illustrates the need to evaluate thoroughly a patient with borderline elevation of serum calcium before renal surgery. Current research indicates that primary hyperparathyroidism is more prevalent than thought previously. A majority of patients with primary hyperparathyroidism have mild asymptomatic disease detected solely by routine serum chemistry screening tests.

Intussusception: analysis of 98 cases

A retrospective study of the clinical features and surgical management of 98 cases of paediatric intussusception treated in New Zealand during the past 16 years is presented. The classic triad of vomiting, rectal bleeding and abdominal pain occurred in only 20 percent of patients. Barium enema examination was used in 67 patients but successful reduction was achieved in only 13. Laparotomy was performed in 85 patients with 1 operative death. Gangrenous bowel was found in 17 patients and 24 required bowel resection with no associated mortality. This high rate of bowel resection appears to be related to the long duration of symptoms before the diagnosis was established. It is concluded that earlier diagnosis is the single factor most likely to reduce morbidity.

A quantitative radioimmunoassay for DNA-binding antibodies

An RIA is described for the measurement of serum immunoglobulins capable of binding to double-stranded or single-stranded DNA. DNA attached to Sephadex G-50 by UV irradiation was used as a solid-phase immunoabsorbent for DNA-binding proteins from serum. GAH IgG (125l-labeled) and GAH IgM (131l-labeled) were used to detect the human immunoglobulins bound onto the washed DNA-Sephadex. The quantities of immunoglobulins bound were determined by comparison with a standard curve constructed by dilution of a plasma from a SLE patient containing known amount of bound, DNA-specific IgM and IgG. Another RIA was employed for measuring levels of IgG and IgM. In combination with measurements of the total serum IgM and IgG, the RIA allowed for the determination of the fraction of the total serum IgM or IgG that was specific for double- or single-stranded DNA. For pool of normal human sera the quantities were as follows: 0.04% of the total IgM and 0.001% of the total IgG bound double-stranded DNA; 0.22% of the total IgM and 0.05% of the total IgG bound single-stranded DNA. This capability is important because information regarding the quantitative measurement of antibodies to DNA and their class determination may be of significance in monitoring the status of subjects with SLE.

Interaction between benzo[a]pyrene and mouse skin in organ culture

An in vitro method for studying the interaction between tritiated benzo[a]pyrene ([3H]BP) and intact mouse skin was investigated. [3H]BP was applied to the epidermal surface of the skin floating on medium, and radioactivity in the medium was measured periodically. After 48-h incubation, about 45% of the radioactivity was in the medium; of this amount, about 80% accumulated during the first 24 h. Incubation temperature, metabolic inhibitors, and the amount of BP applied caused pronounced effects on accumulation; slight to moderate effects were noted for the type and volume of medium and vehicle used. Results of the temperature and inhibitor experiments indicated that accumulation of radioactivity depended on cell viability. About 80% of the radioactivity in the medium was water soluble, showing that biotransformation of BP by skin cells occurred. We are using the skin organ culture method to help understand the interaction of mammalian skin with hydrocarbon mixtures. A study of these interactions may lead to metabolic, cytotoxic, and macromolecular-binding profiles that characterize a carcinogenic mixture of hydrocarbons.

Binding of benzo [a]pyrene to epidermal DNA and RNA as detected by synchronous luminescence spectrometry at 77 K

The fluorescence associated with benzo[a]pyrene [BP] moieties covalently attached to the nucleic acid (DNA plus RNA) isolated from the epidermis of BP-treated mice was examined at 77 K in frozen aqueous solutions by use of a photon-counting fluorimeter operating in the synchronous scanning mode. The excitation and emission wavelengths were scanned simultaneously with the monochromators set 28 nm apart. This setting coincides with the difference in wavelength between the excitation and emission maxima for the fluorescence of bound BP. Currently the level of detection is in the order of 1 BP residue per 200,000 bases in 40 microgram of nucleic acid. This amount of nucleic acid can be isolated from the skin of a single mouse. The method described here is generally useful for detecting the binding to DNA of nonradioactive carcinogenic polynuclear aromatic which might occur following the topical application to animal skin in vivo of complex hydrocarbon mixtures such as synthetic fuels and crude oils.

Orthophosphate therapy decreases urinary calcium excretion and serum 1,25-dihydroxyvitamin D concentrations in idiopathic hypercalciuria

Orthophosphate treatment of patients with idiopathic hypercalciuria reduces the urinary excretion of calcium. To examine the role of altered vitamin D metabolism in reducing the renal excretion of calcium, we studied 11 patients with idiopathic hypercalciuria before and after 2 weeks of treatment with oral neutral orthophosphate (2 g phosphorus/day). Variables measured were urine calcium and phosphorus and seseserum calcium, phosphorus, immunoreactive parathyroid hormone, and 1,25-dihydroxyvitamin D [1,25-(OH)2D]. Oral phosphate treatment significantly decreased urine calcium excretion [mean change (delta), -123 mg/24 h], increased urine phosphorus (mean delta, serum levels of 1,25-(OH)2D (mean delta, -22 pg/ml). Pretreatment levels of 1,25-(OH)2D were high when compared with levels in age-matched controls, whether assessed as the arithmetic mean (57 vs. 33 pg/ml; P < 0.025), the logarithmically normalized (42 vs. 27 pg/ml). Phosphate treatment decreased serum levels of 1,25-(OH)2D to a mean of 35 pg/ml (logarithmically normalized mean, 22 pg/ml; median, 21 pg/ml), values not significantly different from those of normal controls. Serum calcium and phosphorus concentrations were not changed by treatment. Serum immunoreactive parathyroid hormone values increased minimally within the normal range (mean delta, +2 microleq/ml; P <0.025). We conclude that the effect of oral phosphate therapy in decreasing urinary calcium excretion may involve the reduced synthesis of 1,25-(OH)2D, independent of altered parathyroid function.

Renal brush border membrane adaptation to phosphorus deprivation: effects of fasting versus low-phosphorus diet

Alimentary phosphorus deprivation due to a low-phosphorus diet (LPD) elicits a profound antiphosphaturia and an increase in sodium-dependent inorganic phosphate (Pi) uptake by renal cortical brush border membrane (BBM) vesicles. But, in alimentary phosphorus deprivation due to total fasting, high urinary excretion of Pi persists. In the present study, we determined whether low tubular reabsorption of Pi in fasting is due to a diminished capacity of the specific Pi transport system with the renal cortical luminal BBM or whether it is due to a reduced transepithelial reabsorption of Pi because of metabolic conditions occurring in proximal tubule cells during fasting. Sodium-dependent Pi transport in compared with fasted rats or rats fed a normal phosphorus diet. Sodium-dependent uptake of D-glucose was significantly lower in LPD rats, compared with fast animals or animals fed a normal diet. Thus, in contrast to LPD, fasting does nt elicit an increase in Pi transport and a decrease in D-glucose transport across the isolated renal BBM. The same differences in BBM transport of Pi were present also in thyroparathyroidectomized rats. Further experiments demonstrated that the adaptation of renal function and the renal BBM transport to LPD are overridden by a subsequent period of total fasting. Results of the present study show that fasting both prevents and reverses the renal response of rats to alimentary phosphorus deprivation. The differences in Pi excretion between fasted rats, LPD rats, and LPD rats subsequently fasted are attributed, at least in part, to specific adaptive changes in sodium-dependent Pi transport across the luminal BBM, rather than to alterations in other cellular (metabolic) components of transepithelial Pi reabsorption in the proximal tubule.