Increased cation transport inmdr1-gene-expressing K562 cells

Cation-transport properties were compared in a human leukemic cell line (K562) and its vincristineselected,mdr1-gene-expressing sublines (K562/Vcr30 and K562/Vcr150) by the capacity of the cells to accumulate the potassium analogue thallium (²⁰¹Tl). Determination of the time course of thallium accumulation in the absence and presence of ouabain, an inhibitor of sodium-potassium adenosine triphosphatase (ATPase), showed that the initial (at 20 min) rate of ouabain-resistant uptake was about 70% higher in the K562/Vcr30 cells than in the parental line. The maximal rate (V_max) of ouabain-resistant uptake was 78 mmol/h for K562 cells and 115 mmol/h for K562/Vcr30 cells, and the Michaelis constant (K _m) was 0.37 and 0.18 mmol, respectively. Bumetanide (50 M), a specific inhibitor of ouabain-resistant Na–K–Cl cotransport, inhibited the elevated²⁰¹TI uptake in K562/Vcr150 cells but had no effect on cellular vincristine accumulation. Incubation with different multidrug resistance (MDR)-reversing agents (verapamil as well as cyclosporin A and its analogue PSC833) had no significant effect on²⁰¹Tl uptake. Membrane depolarization by an elevation of the potassium concentration in the incubation medium did not affect vincristine accumulation in any cell line, which indicated that the changed drug-transport properties inmdr1-gene-expressing cells were not due to membrane hyperpolarization. It was concluded that P-glycoprotein-positive cells have a more efficient ouabain-resistant cation-transport mechanism than to cells without P-glycoprotein. A functional relationship between this phenomenon and MDR was not identified.     

Clinical significance of technetium-99m methylene diphosphonate myocardial uptake: association with carcinoma of the prostate

Benign myocardial uptake of technetium-99m labelled phosphates, not related to cardiac or metabolic disorders, has been documented except in the case of^99mTc-methylene diphosphonate (MDP). The aim of this study was to assess the frequency of myocardial uptake and its possible association with malignant tumours in general and prostatic carcinoma in particular. We reviewed bone scintigrams performed with either^99mTc-hydroxydiphosphonate (HDP) or^99mTc-MDP over a period of more than 2 years for all patients with prostatic carcinoma and a matching group of patients suffering from other malignant and non-malignant disorders. A total of 965 scintigrams of 812 patients (males=559, females=253; age range 50–91 years, average age 69.2 years) were reviewed. Increased myocardial uptake was detected in 19 scintigrams (MDP=13, HDP=6) of 18 patients (17 males, one female). Most of the male patients with increased myocardial uptake had prostatic carcinoma (13/17) and were over 80 years of age (12/17). All patients were free of any cardiac or noncardiac disorder that might account for such uptake. When scintigraphy was repeated in the same patient, the uptake of^99mTc-HDP was more diffuse and of higher grade than that of^99mTc-MDP Benign myocardial uptake of^99mTc-MDP is more common than previously thought. Although uptake of radiophosphates is attributed to asymptomatic atherosclerotic changes associated with old age, a strong association with prostatic carcinoma exists which may indicate variations in the bone: soft tissue affinity of different MDP complexes.     

Net postprandial utilization of [15N]-labeled milk protein nitrogen is influenced by diet composition in humans

The aim of this study was to follow the fate of dietary nitrogen to assess the postprandial utilization of purified milk protein and to determine the acute influence of energy nutrients. For this purpose, a [15N]-labeling dietary protein approach was used. Twenty-five subjects swallowed an ileal tube and ingested [15 N]-milk protein alone or supplemented with either milk fat or sucrose. The absorption and postprandial deamination of dietary protein was monitored for 8 h. Sucrose delayed the absorption of protein longer than fat, but the ileal digestibility did not differ among groups (94.5-94.8%). Sucrose, but not fat, significantly reduced the postprandial transfer of [15N]-milk nitrogen to urea. Consequently, the net postprandial protein utilization (NPPU) of milk protein calculated 8 h after meal ingestion was 80% when ingested either alone or supplemented with fat and was significantly greater with sucrose (NPPU = 85%). This study shows that energy nutrients do not affect the nitrogen absorption but modify the metabolic utilization of dietary protein in the phase of nitrogen gain. Our method provides information concerning the deamination kinetics of dietary amino acids and further allows the detection of differences of dietary protein utilization in acute conditions. The diet composition should be carefully considered, and protein quality must be determined under optimal conditions of utilization.     

The management of urinary candidiasis in cystectomized patients

Presentation of eight cases of urinary candidiasis in patients who underwent radical cystectomy and were managed using by-pass of the urinary tract, oral antifungal therapy and solutions in the way of intermittent instillation through nephrostomy catheters.     

Trigonocervicoprostatomy. Indications and results from 100 case reports

Trigonocervicotomy is a barely invasive technique for the treatment of infravesical obstruction, first introduced in the 60's by Turner-Warkic and Orandi. To achieve good results with this procedure, the selection criteria must take into account a series of parameters such as age, sexual activity, PSA, prostate weight (below 30 grams) and others. In addition to its low morbidity, a larger percentage of patients preserve ejaculation than with the use of other techniques, also the neck sclerosis rate being lower as seen in all our series and expertise. The efficacy of this technique was studied on 100 patients.     

Risk behaviours and seroprevalence to HIV, HBV and HCV in patients of the AIDS information and prevention center in Valencia, Spain

OBJECTIVE: The purpose of this study was to describe the sociodemographic and serologic profiles in a first time consultant population at the Information and AIDS Prevention Center of Valencia (Spain). In addition, the HIV infection risk factors were analyzed. METHOD: A cross-sectional study was performed on 1,573 persons who consulted during the year 1995. Sociodemographic and infection risk practices data were recorded and serologic information about HIV, HBV and HCV infection were obtained. Exact binomial method with a 95% interval confidence was used to calculate infection prevalence and the chi square test to make comparisons between qualitative variables. RESULTS: Sex distribution was 66,1% males and 31,9% females; mean age was 29,01 (SD: 9.2) years. Sexual intercourse without condom (25.2%) and parenteral drug abusers (22.6%) were the more frequent risk groups seeking consultation about HIV infection. Global HIV infection prevalence was 12.7% (95% CI= 11,2-14,5%). Among HIV seropositive patients, sexual transmission accounted for 30.8% of cases, of which 69.4% were heterosexual relations. The HIV infection prevalence for different risk groups were the following: parenteral drug abusers 36.8% (95% CI= 31,7-42%), heterosexual intercourse with an HIV-infected partner 24.1% (95% CI= 17,1-32,2%) and homosexual intercourse between men 9,5% (95% CI= 5,8-14,5%). HCV antibody prevalence for parenteral drug abusers was 81.2% (95% CI= 76,7-85,1%). Risk practices with a statistically significant association with HIV infection were: being an injecting drug abuser, as well as having an HIV infected and/or a injecting drug abuser partner. CONCLUSIONS: Drug parenteral abusers are still the target population for prevention programs. Data suggest that prevention and sexual education programs must continue. The main effort should be focused on the young population and on sexual partners of injecting drug abusers and/or HIV seropositive partners.     

Complications of Penile Lengthening and Augmentation Seen at 1 Referral Center

Purpose

Complications of the recent cosmetic technique of penile lengthening and girth enhancement are reviewed.

Materials and Methods

During a 16-month period 12 men presented with complications of penile augmentation performed elsewhere. All 12 patients had undergone release of the suspensory ligament and 10 had received autologous fat injection.

Results

the chief complaint was poor cosmetic appearance (irregular residual fat nodules in 7 men, skin deformity and scarring in 4 and scrotalization in 4). Reoperation was necessary in 6 patients, wound complications occurred in 6 and sexual dysfunction was reported by 4. Only 1 patient reported a subjective increase in penile length.

Conclusions

Although a verifiable complication rate may never by available, the morbidity of elective penile lengthening and girth enhancement is noteworthy. These cosmetic techniques should be regarded as experimental.