Effect of differing concentrations of parathyroid hormone on rat renal electrolyte excretion

Urinary clearance studies were performed on acutely thyroparathyroidectomized rats to study the effect of a range of parathyroid hormone (PTH) concentrations on renal electrolyte transport. PTH 0.1 U, prime and per hour, significantly increased the plasma calcium concentration, yet fractional calcium excretion was increased by 47.5% and inorganic phosphate excretion remained unaltered. PTH 1 U produced a similar increase in the plasma calcium concentration. However, urinary calcium excretion was unchanged when compared with control animals and a small phosphaturia occurred (from 0.1 +/- 0.1 to 0.8 +/- 0.2%; P less than 0.05). PTH 10 U decreased fractional calcium excretion by 50% and increased fractional phosphate excretion from 0.4 +/- 02. to 19.4 +/- 1.7% (P less than 0.01). Changes in urinary magnesium excretion were similar to those of calcium, being increased with the lowest PTH concentration yet decreased with a 100-fold increase in PTH concentration. These data suggest that PTH, at a low physiological concentration that acts on bone, does not directly alter renal electrolyte handling. High physiological concentrations of PTH, however, produce a brisk phosphaturia and reduce calcium and magnesium excretion. A reappraisal of the accepted role of PTH on renal calcium conservation is therefore required.

Feasibility of altering type A behavior pattern after myocardial infarction. Recurrent Coronary Prevention Project Study: methods, baseline results and preliminary findings

We studied 1035 consecutive postinfarction patients to determine the feasibility of altering type A behavior and the effect such alteration might have on subsequent rates of infarction and cardiovascular death. Approximately 300 subjects were enrolled in small groups and primarily received cardiologic counseling on the usually accepted coronary risk factors. Six hundred subjects received, in addition to cardiologic counseling, advice and instructions designed to diminish the intensity of their type A behavior. The remaining subjects, serving as controls, received no counseling, but were examined and interviewed annually, as were those who dropped out of counseling groups. More than 98% of the 1035 subjects exhibited moderate-to-severe type A behavior during a videotaped structured interview. After the first year of this 5-year study, the rates of infarction and cardiovascular death were lower (p less than 0.01 and p less than 0.05, respectively) among subjects who received both cardiologic and behavioral counseling than among the control subjects. The rate of nonfatal infarction was lower (p less than 0.05) among subjects who received behavioral counseling than among those who received only cardiologic counseling or those who dropped out of either counseling group. The circumstances that most often preceded recurrent infarction or cardiovascular death were emotional crisis, excess physical activity, ingestion of a single fatty meal or a combination of these phenomena.

Therapy for acute cystitis in adult women. Randomized comparison of single-dose sulfisoxazole vs trimethoprim-sulfamethoxazole

One hundred seventeen unselected women with symptoms of acute cystitis were randomized to groups for immediate therapy with one of the following four single-dose regimens: (1) 1 g of sulfisoxazole; (2) 2 g of sulfisoxazole; (3) a combination of trimethoprim, 160 mg, and sulfamethoxazole, 800 mg; and (4) a combination of trimethoprim, 320 mg, and sulfamethoxazole, 1,600 mg. Forty-one women were excluded, 13 did not return for follow-up, and 28 did not have significant bacteriuria in the pretherapy culture. Escherichia coli was isolated in 81% of infections. Antibacterial activity was significantly greater in urine collected during the 24 hours after therapy in those who received trimethoprim-sulfamethoxazole. However, overall cure varied from 85% to 95%, without any great differences between the regimens. The rate of cure of 69% in the 13 patients with presumptive evidence of renal infection (antibody-coated bacteria present) was significantly lower than the rate of cure of 95% in women without evidence of renal infection. Single-dose therapy with these regimens was safe and effective in adult women with symptoms of acute cystitis, regardless of the localization of the site of infection.

Perceptions and attitudes of hyperactive children and their mothers regarding treatment with methylphenidate

Fifteen hyperactive children and their mothers were interviewed regarding their knowledge, perception, and attitudes toward treatment with methylphenidate 6 months after commencing a stimulant regime with the child. Measures of locus of control and self-esteem were also administered to the child. The results indicated that mothers and children agreed on the effects of medication and knowledge about the cause of hyperactivity. Both mothers and children had mixed feelings about medication. Most of the children felt that continuing with this treatment was important and seemed to be more concerned than their mothers over negative consequences if medication was stopped. Although it has been suggested that impaired self-esteem may be a consequence of children seeing improved behaviour as a result of medication rather than self-control, the results indicated an increase in both self-esteem and internal locus of control during the 6-month period of the study.

Trimethoprim alone in the treatment and prophylaxis of urinary tract infection

Trimethoprim was used alone to treat urinary tract infections in 20 women who were unable to tolerate sulfonamides. Of ten acute symptomatic urinary tract infections, four were cured, three were not, and three cases could not be evaluated. Two other women received trimethoprim for suppression of infection complicating stag-horn calculi. The conditions of both patients improved clinically but the urine remained infected. Eight women treated prophylactically with low-dose trimethoprim for recurrent urinary tract infection accumulated a total of 16 patient-years of prophylaxis. During treatment, the incidence of infection was 0.56 per patient-year compared with 4.25 infections in the year preceding study. Adverse reactions occurred in eight of 20 patients and administration of the drug had to be stopped in five cases. Trimethoprim alone is effective for the treatment and prophylaxis of urinary tract infections, but may cause a high incidence of adverse reactions in patients known to be sensitive to sulfonamides.

A comparison of the efficacy of nalidixic acid and cephalexin in bacteriuric women and their effect on fecal and periurethral carriage of enterobacteriaceae

Eighty-one women were randomly selected for treatment with nalidixic acid (1 g four times a day) or cephalexin (500 mg four times a day) as therapy for 131 episodes of bacteriuria localized using the antibody-coated bacteria (ACB) test. Bladder infections were treated for three days and renal infections for 14 days. Rates of cure were not significantly different between treatment groups in each drug regimen. However, significantly more relapses occurred in the patients with ACB-positive infections treated for 14 days with cephalexin than in those treated for 14 days with nalidixic acid. More early reinfections occurred in the cephalexin-treated group after both three and 14 days of therapy. Resistance to nalidixic acid developed in the infecting bacteria in the urine during therapy with nalidixic acid in 3% of women after three days and in 16% of women after 14 days. Simultaneous resistance appeared in the urine, periurethral area, and fecal flora of these patients.

Acute effect of calcitonin on rat renal electrolyte transport

Renal clearance studies were performed on parathyroid-intact and acutely thyroparathyroidectomized (TPTX) rats to clarify calcitonin (CT) action on renal electrolyte transport. Although CT (0.15 U x 100 g body wt-1 x h-1) reduced fractional excretion of calcium and magnesium by 72 and 46%, respectively, in TPTX rats without altering sodium and phosphate excretion, a 10-fold increase in CT (1.5 U) caused a smaller reduction in calcium and magnesium excretion and significantly increased sodium and phosphate excretion. A higher CT dose (15 U) did not alter calcium excretion, increased magnesium excretion, and caused an even greater increase in sodium and phosphate excretion. Results in parathyroid-intact animals were similar. Despite the fall in plasma calcium following CT administration, the filtered calcium load was unaltered due to a concomitant increase in glomerular filtration rate. Calcium infusion prior to CT (0.15 U) prevented a detectable fall in plasma calcium concentration. However, a 45% fall in fractional calcium excretion occurred despite the significant increase in filtered calcium. These data suggest that the physiological role of calcitonin on the nephron is to conserve calcium. Reports of increased electrolyte excretion presumably reflect a depressant effect of pharmacological doses of CT on nephron function.

Training in the use of Goal Attainment Scaling

Goal Attainment Scaling is emerging as one of the most frequently utilized methods of evaluating mental health programs. However, little material is available on the practical problems encountered in training mental health clinicians to use Goal Attainment Scaling. This report details some of the difficulties encountered and the training program that evolved when a large scale research program used Goal Attainment Scaling as the criterion of outcome.

Role of cervicovaginal antibody in the pathogenesis of recurrent urinary tract infection in women

Introital colonization with Enterobacteriaceae is considered to be one of the principal predisposing factors to recurrent urinary tract infections (UTI) in adult females. One proposed mechanism allowing introital colonization in these patients is the absence of local cervicovaginal antibody. To test this hypothesis, we examined cervicovaginal washings from 22 patients with a history of recurrent UTI and 29 normal controls with no history of UTI for specific local antibody by using indirect immunofluorescence. No significant difference in antibody was found in these populations. Fourteen percent (3/22) of the patients had antibody to their introital Escherichia coli and 34% (10/29) of the controls had antibody to their fecal E. coli. Consequently, a sensitive radioimmunoassay technique was developed to detect cervicovaginal antibody. A solid phase was prepared by coupling to Sepharose 4B a pool of eight serogroups of E. coli which are frequently implicated in UTI. Serial dilutions of cervicovaginal washings were reacted with the solid phase, and the absorbed anti-E. coli antibodies were detected by the uptake of (125)I-labeled anti-human immunoglobulin G (IgG) or anti-human IgA. The antibody levels were quantitated by interpolation on a standard curve prepared by using immunospecifically purified human anti-E. coli antibodies. IgG and IgA levels were measured in washings from 10 colonized patients, 13 non-colonized patients, and 12 controls. There were no significant differences in IgG and IgA levels in cervicovaginal washings among the three groups. In these studies, introital colonization was not related to cervicovaginal antibody.

Prophylaxis of recurrent urinary tract infection in female patients. Efficacy of low-dose, thrice-weekly therapy with trimethoprim-sulfamethoxazole

Thirty-two women with recurrent urinary tract infections were treated after eradication of existing infections with a mixture of 40 mg of trimethoprim and 200 mg of sulfamethoxazole thrice weekly at bedtime for six months. Six preadolescents received one half this dose. During 21.3 cumulative patient-years of prophylaxis, one infection due to Streptococcus faecalis and one due to a sulfamthoxazole-and trimethoprim-sensitive Escherichia coli occurred--an infection incidence of 0.1 per patient-year. During prophylaxis, 61 of 72 periurethral cultures and 24 of 51 anal canal cultures failed to yield Enterobacteriaceae. One patient had transient colonization with a trimethoprim-resistant E coli during prophylaxis. Twenty-one patients had recurrent infection within six months of discontinuation of prophylaxis, with a mean time to recurrence of 2.6 months. One infection recurred 26 weeks following prophylaxis with a Proteus mirabilis. Thrice-weekly trimethoprim-sulfamethoxazole therapy was effective for prophylaxis of recurrent urinary tract infections and did not predispose to colonization or infection with trimethoprim-resistant Enterobacteriaceae.

Biochemical basis for the enhanced toxicity of deoxyribonucleosides toward malignant human T cell lines

Human malignant T cell lines have high levels of deoxyribonucleoside phosphorylating activity and low levels of deoxyribonucleotide dephosphorylating activity. When incubated with deoxyadenosine or thymidine, the malignant T cell lines rapidly accumulate toxic concentrations of dATP and dTTP, respectively. This unusual pattern of deoxyribonucleotide metabolism renders the malignant T cells especially vulnerable to the toxic effects of deoxyribonucleosides and related analogues.

Regulation of purine de novo synthesis in cultured human fibroblasts: the role of P-ribose-PP

Procedures for assaying the rate of purine de novo synthesis in cultured fibroblast cells have been compared. These were (i) the incorporation of [(14)C]-glycine or [(14)C]formate in alpha-N-formylglycinamide ribonucleotide (an intermediate in the purine synthetic pathway) and (ii) the incorporation of [(14)C]-formate into newly synthesised cellular purines and purines excreted by the cell into the medium. Fibroblast cells, derived from patients with a deficiency of hypoxanthine phosphoribosyltransferase (HPRT-) (EC 2.4.2.8) and increased rates of purine de novo synthesis, were compared with fibroblasts from healthy subjects (HPRT+). Fetal calf serum, which was used to supplement the assay and cell growth medium, was found to contain sufficient quantities of the purine base hypoxanthine to inhibit purine de novo synthesis in HPRT+ cells. This inhibition was the basis of differentiation between HPRT- and HPRT+ cells. In the absence of added purine base, both cell types had similar capacities for purine de novo synthesis. This result contrasts with the increased rates of purine de novo synthesis reported for a number of human HPRT- cells in culture but conforms recent studies made on human HPRT- lymphoblast cells. The intracellular concentration and utilisation of 5-phosphoribosyl-1-pyrophosphate (P-Rib-PP), a substrate and potential controlling factor for purine de novo synthesis, were determined in HPRT- and HPRT+ cells. The rate of utilisation of P-Rib-PP in the salvage of free purine bases was far greater than that in purine de novo synthesis. Although HPRT- cells had a 3-fold increase in P-Rib-PP content, the rate of P-Rib-PP generation was similar to HPRT+ cells. Thus, in fibroblasts, the concentration of P-Rib-PP appears to be critical in the control of de novo purine synthesis and its preferential utilisation in the HPRT reaction limits its availability for purine de novo synthesis. In vivo, HPRT+ cells, in contrast to HPRT- cells, may be operating purine de novo synthesis at a reduced rate because of their ability to reutilise hypoxanthine.

Clinical efficacy and toxicity of netilmicin in the treatment of gram-negative infections

Netilmicin, a new semisynthetic aminoglycoside antibiotic, was used to treat 41 infections in 38 patients. The outcome of four infections could not be evaluated: two patients received inadequate therapy and two did not have gram-negative infections. Clinical improvement occurred in 36 (97%) of the 37 gram-negative infections, and bacteriologic cure occurred in 30 (86%) of the 35 evaluable infections. Therapeutic serum concentrations of netilmicin were readily achieved by both intramuscular and intravenous routes. Reversible ototoxic effects occurred in 1 (3%) of 35 courses of therapy evaluated, reversible nephrotoxic effects occurred in 5 (14%) of 36 courses and mild reversible alterations in liver function occurred in 3 (19%) of 34 courses. Netilmicin appears to be effective and safe in the treatment of aerobic gram-negative infections.

Uricosuric response to increasing doses of the indanone diuretic MK-196 in healthy volunteers

Doses of 20, 40, 60 and 80 mg of the indanone diuretic MK-196 and 40 mg of frusemide were administered in random order to 5 healthy volunteers in a stable metabolic state, on the same day for 5 consecutive weeks. Diuresis, natriuresis and kaluresis increased with increasing doses, the natriuresis lasting for about 12 h and the kaluresis for about 24 h. Uricosuria increased with increasing doses of MK-196 and lasted for about 6 h. The uricosuria was followed by urate retention, so that there was little net change in the renal excretion of urate. Significant weight loss occurred, so that there was probably some associated plasma volume contraction, which would promote urate retention. By contrast, frusemide caused a reduction in renal excretion of urate at all times.

Altered leucyl-transfer RNA synthetase from a mammalian cell culture mutant

Altered leucyl-tRNA synthetase from a mammalian cell culture temperature-sensitive mutant, tsHl, was compared with enzyme from normal wild type Chinese hamster ovary cells. The mutant enzyme had a Km for leucine four times larger than that of wild type and enzyme levels 3-10% that of wild type. The presence of tRNA was necessary during in vitro heating of the mutant enzyme to allow expression of thermolability while the presence of tRNA protected wild type enzyme against thermal inactivation. The tsHl enzyme was stable when heated alone or in the presence of tRNA, leucine, and ATP simultaneously. The mutant's enzymes aminoacylated tRNALeu, tRNAVal, and tRNAIle with fidelity in vitro as determined by cochromatography of the amino-acyl-tRNA isoacceptors on RPC-5 reversed phase chromatography. The mutant failed to show any defect other than the direct formation of leucyl tRNALeu by leucyl-tRNA synthetase.

Psychiatric morbidity in general practice and the community

The "General Health Questionnaire" was used to assess the psychiatric morbidity among 365 consecutive attenders at a general practice and to compare this with a systematic random sample of 213 patients drawn from the lists of the same practice. Those attending a general practitioner are shown to be more psychiatrically disturbed than a random sample of the practice population, and this difference remains when those attending for psychological symptoms are discounted. Various social and demographic characteristics which distinguish between those who do and those who do not attend a doctor with a given set of psychological symptoms are described.