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PubMed1990

Epizootiologic evaluation and quantitative analysis of urinary calculi from 150 cats.

One hundred fifty specimens of urinary calculi from 150 cats were analyzed by at least 1 of 4 quantitative methods. Struvite (magnesium ammonium phosphate) was the predominant mineral substance encountered, with 104 (69%) of the calculi being composed entirely of struvite and 23 (15%) being composed partially of struvite. Most (93%) of the calculi were located in the urinary bladder. Growth of bacteria was observed in samples from calculi or urine from 30 (41%) of 74 cats. Coagulase-positive staphylococci were isolated from the urine or calculi from 17 cats (45% of bacteria isolated). Ten other bacterial species were isolated. Median and mean ages of the cats were 5.0 and 5.1 years, respectively. Domestic short-hair and domestic longhair breeds predominated. Fifty-seven percent of the calculi came from females, 43% from males. The distribution by gender did not differ significantly (P greater than 0.2) among the 3 groups (domestic shorthair, domestic longhair, and other). However, the distribution of struvite calculi differed significantly (chi 2 = 15.5, P less than 0.001) by age and gender; among cats less than or equal to 2 years of age, males predominated 2:1 over females, and among cats greater than 2 years of age, females predominated by nearly 3:1 over males. When compared with the general population, females greater than 2 years old were significantly (chi 2 = 15.4, P less than 0.001) overrepresented.

Age Factors↗
PubMed1990

Metabolic evaluation of urolithiasis.

The relatively simple scheme described here should become part of the urologist's stone evaluation plan. It allows for the rapid identification of the metabolic disorders and the prompt implementation of appropriate therapy. With a stone remission rate of 70 to 90 per cent and a reduction in the stone formation rate of 88 to 100 per cent, an overwhelming incentive exists to master this evaluation scheme.

Calcium↗
PubMed1989

The incidence and composition of salivary stones (sialolithiasis) in Iran: analysis of 95 cases--a short report.

In a 3 year period 95 patients with sialolithiasis were studied, giving an annual incidence of 7.3 per 1000 admissions. The male to female ratio was 2.5:1. Salivary gland stones comprised 73.68 per cent (N = 70 patients). Chemical analysis of calculi taken from 88 patients, showed that 89.77 per cent (N = 79 patients) were with phosphate salts stones, 7.98 per cent (N = 7 patients) were with oxalate salts, and 2.27 per cent (N = 2 patients) were with urate salts. Salivary gland infection was present in 91.57 per cent (N = 87 patients) of whom 75.86 per cent (N = 66 patients) and 24.14 per cent (N = 21 patients) were females. A high ambient temperature and dehydration with poor oral hygiene are probable causative factors.

Adolescent↗
PubMed1989

Toxicity of an attapulgite sample studied in vivo and in vitro.

Conflicting data are found in the literature concerning the carcinogenic potency of attapulgite. We tested the carcinogenic potency of French attapulgite in rats, and compared it with 2 chrysotile samples: Rhodesian UICC (Ch A) and short Canadian fibres (Ch C). The mean length of the fibres was 0.77 micron (attapulgite), 3.21 microns (Ch A) and 1.25 microns (Ch C). The mean diameter was 0.06 micron in the 3 samples. The particles (20 mg) in saline were inoculated into the pleural cavity of Sprague-Dawley rats allowed to survive for their full lifespan. The incidence rates of mesothelioma were: 0% (saline controls), 0% (attapulgite), 19% (ChC) and 48% (Ch A). In vitro studies were carried out using cultures of rat pleural mesothelial cells (RPMC). Attapulgite and Ch C did not modify cell growth except at high doses of 10 micrograms/cm2. Unscheduled DNA synthesis (UDS) was detected using [3H]thymidine incorporation in confluent RPMC (GoG1 arrested) and a scintillation method. UDS was stimulated with either Ch A or Ch C at doses ranging from 2 to 10 micrograms/cm2. In contrast, attapulgite did not significantly enhance [3H]thymidine incorporation at doses ranging from 2 to 20 micrograms/cm2. The results show that the attapulgite tested here had no carcinogenic potency. The in vivo and in vitro reactivity of the fibres used in this experiment might perhaps be related to the fibre size; however, other parameters may also be important.

Animals↗
PubMed1989

[Introduction of an enzyme method for determining pyrophosphate in urine--a comparative study between patients with calculi and normal probands].

Interest aroused towards pyrophosphate as a possible inhibitor in calcium oxalate and phosphate lithiasis. A procedure for the quantitative determination of pyrophosphate in urine suitable for use in clinical laboratories is described. The reproducibility of the method was assessed by within-run and between-run reproducibility studies and the accuracy of the method was obtained by determining the amount of pyrophosphate recovered in urine samples. The present study compares the pyrophosphate excretion and concentration between a control group and a calcium oxalate stone former group.

Calcium Oxalate↗
PubMedDate not supplied

[Anabolic effects of sodium selenite, vitamin E and retabolil in experimental hypotrophy induced by a pesticide].

Forty Chinchilla rabbits of both sexes were examined for changes in some parameters of protein, lipid and trace elements metabolism (total protein, protein fractions, urea, residual nitrogen in blood serum, lipids, total cholesterol, free cholesterol, diglycerides, phospholipids, triglycerides, free fatty acids and the trace elements selenium, iron, zinc and so forth in the liver) during the animals' poisoning with the defoliant magnesium chlorate. A study was made of the effect on these changes of the administration for 3 weeks of sodium selenite (15 micrograms/kg), vitamin E (25 mg/kg) and retabolil (2 mg/kg once a week). It has been established that the combined administration of these agents removes and prevents the changes in protein, lipid and trace elements (hypoproteinemia, dysproteinemia and impairment of the nitrous balance) and lipid metabolism because of the animals' poisoning with magnesium chlorate.

Anabolic Agents↗
PubMed1989

[Clinical studies on childhood urolithiasis during the past 22 years].

We have studied retrospectively 68 children who presented with urolithiasis between 1965 and 1986. Male to female ratio was 1.83 to 1 and the mean age was 9.5 years. Fifty four children (79%) had calculi in the upper urinary tract, 9 (13%) had in the lower, and 4 (6%) had calculi both in the upper and lower urinary tract. The most common presenting symptoms were gross hematuria (53%) and abdominal or flank pain (38%). Predisposing factors could be found only in 21 children (31%). Twenty four of the 68 patients (35%) had open surgery and 16 patients (24%) passed their stones spontaneously. Twenty one stones were analyzed by infrared spectroscopy. Infectious stone was more frequent than in adult cases. Among children five years old and younger, infectious stone was the most frequent. Among children over five years old, the number of idiopathic calcium stone has been on the increase with the years.

Adolescent↗
PubMed1989

[The prognosis of patients with struvite calculi with remaining/recurrent calculi and treatment refractory urinary tract infections].

29 patients suffering from recurrent struvite stones and/or persistent urinary tract infection were analyzed retrospectively with a follow-up time of 10 +/- 6 years. A sanitation of the urease-positive urinary tract infection was possible in 12 patients (41%). After 10 out of 53 operations (19%) rest stones were found. An unilateral nephrectomy was done in 3 cases. Despite rest calculi and persistent urinary tract infection no further calculus growth or deterioration of renal function was found in most patients.

Combined Modality Therapy↗
PubMed1987

Pleural carcinogenic potency of mineral fibers (asbestos, attapulgite) and their cytotoxicity on cultured cells.

The carcinogenicity of several samples of mineral fibers was tested following injection of 20 mg in the pleural cavity of noninbred Sprague-Dawley rats. Three samples of chrysotile asbestos (mean length: 3.2, 2.1, and 1.2 micron) induced mesotheliomas at a rate of 48, 52, and 19%, respectively. The first sample was acid leached prior to intrapleural injection; in that group, the percentage of mesotheliomas was reduced to 25%. Treatment with amosite and crocidolite resulted in the occurrence of 57 and 56% of mesotheliomas. Acid-treatment of amphiboles did not significantly modify the percentage of mesotheliomas. When the Stanton's fiber dimensions were taken into consideration to correlate with mesothelioma incidence, the observed number of mesotheliomas in the chrysotile-treated animals was much lower than that expected, suggesting that other fiber parameters (chemistry, physicochemistry) play a role in the carcinogenicity. Attapulgite fibers (mean length: 0.77 micron) did not induce tumor, and the mean survival time was of the same order as that observed in the control groups. The injection of quartz resulted in no mesothelioma but did result in 6 malignant histiocytic lymphomas (17%) and 2 malignant schwannomas (6%). In vitro experiments did not show strong correlation between cytotoxicity and the carcinogenic potency of these minerals, but the qualitative cellular responses might give some indications on the fiber's potency. In addition, the in vitro effects of the fibers seem to be modulated by their size.

Animals↗
PubMed1988

Quantitative X-ray diffraction analysis of urinary calculi by use of the internal-standard method and reference intensity ratios.

The internal-standard method and the powder diffractometer have been applied here to the quantitative determination of urinary stone constituents by x-ray diffraction (XRD). Reference intensity ratios determined for six stone substances were used in the reduction of intensity data. Constituent concentrations calculated for 21 stones were compared with values obtained from an element-sensitive technique. We conclude that XRD analysis alone cannot be regarded as a routine technique for the quantitative characterization of uroliths, but that semiquantitative XRD analysis supplemented by accurate quantitative elemental data is more suitable for the precise determination of true stone composition.

Calcium Oxalate↗
PubMed1988

The effects of pyrophosphate on myosin heads and on fiber stiffness.

We have investigated the effect of magnesium pyrophosphate (MgPPi) on the orientation and stiffness of myosin heads in glycerinated muscle fibers. MgPPi is known to bind to the nucleotide site of myosin and to weaken the bond between myosin and actin. The spectra of paramagnetic probes attached to the reactive sulfhydryl on the myosin head were used to monitor the orientation of the head. Addition of 3 mM MgPPi to rigor fibers resulted in a shift of approximately 50% of the myosin heads from a state in which the probes are highly oriented to a state in which the probes are disordered. Experiments in which MgPPi dissociated labeled subfragment-1 from unlabeled fibers support the conclusion that the disordered probes are on myosin heads that are not attached to actin. Addition of MgPPi causes only a small decrease in fiber stiffness, measured by step changes in fiber length. We conclude that up to 50% of the myosin heads can be dissociated from actin with little change in muscle stiffness. Thus stiffness is not a linear measure of the fraction of myosin heads attached to actin. We present a model in which one head of the pair of a myosin molecule binds more weakly to actin and can be dissociated preferentially by the binding of MgPPi.

Animals↗