Biomedical subjects

J Ramon

Publications and source records attributed to J Ramon.

At least 55 records · Page 3Linked to original sources

PubMed1998

[The Mitrofanoff pouch in lower urinary tract reconstruction].

The Mitrofanoff principle, first described in 1980, consists of implanting a tubular organ such as the appendix, ureter, or fallopian tube into the wall of the bladder (or urinary reservoir) to create a non-refluxing, catherizable urinary conduit. Between 1993-1996, 7 men and 1 woman (aged 48-64, average 59) underwent radical cystectomy and urethrectomy combined with the creation of a MAINZ I urinary reservoir (based on the Mitrofanoff principle). In men the indication for the procedure was the diagnosis of invasive transitional cell carcinoma of the bladder with involvement of the prostatic urethra. All patients had refused urinary diversion to an ileal conduit because of its deleterious effect on the quality of life. In all patients the postoperative course was uneventful, apart from intraperitoneal urinary leakage from the reservoir in 1, successfully managed conservatively. The patients have gained full control of urinary drainage, performing intermittent self-catheterizations every 4-5 hours. In 3 patients there were difficulties with catheterization due to stenosis of the conduit, usually at the skin level. None have suffered leakage from the reservoir, during the day, even when it was full. Our experience shows that creation of a continent urinary reservoir according to the MAINZ I technique is an excellent surgical solution for patients in whom the creation of an orthotopic reservoir is impractical. The use of the umbilicus as a stomal site preserves normal body image and thus does not interfere with quality of life as in those undergoing radical cystectomy.

Female↗

PubMed1998

Immunohistochemical analysis of rasGTPase activating protein (rasGAP) in prostate cancer.

The ras protooncogene plays a key role in the signal transduction cascade of activated growth factors, and is known to be activated or overexpressed in multiple tumor types, including prostate cancer. rasGTPase activating protein (rasGAP), a major downregulator of ras activity, has been shown to be underexpressed in human trophoblastic tumors, and presumably acts as a tumor suppressor gene product in these neoplasms. To assess the role that rasGAP plays in the development of prostate cancer, we performed immunohistochemical analyses with anti rasGAP antibodies of 125 human prostate tumors from Israel. Staining results were correlated with Gleason grade. In the majority of tumors (99/125-79%) there was either no staining or the tumor and surrounding benign glands had a similar pattern of staining. In up to 16% of the tumors, cytoplasmic, tumor-specific loss of expression was noted, presumably indicative of the role of rasGAP as a tumor suppressor gene. Unexpectedly, in up to 21% of the tumors, nuclear staining was demonstrated, and in about 20% of these, there was an accompanying loss of expression in the non neoplastic cytoplasm. Neither cytoplasmic nor nuclear staining correlated with Gleason grade. These findings of nuclear staining by anti-rasGAP are intriguing, since it is the first time that nuclear translocation of rasGAP is demonstrated, which might indicate that in this subset of tumors, rasGAP acts as a direct acting oncogene. The data indicate that rasGAP may play a dual regulatory role in prostate proliferation and that nuclear expression of it may be associated with malignant transformation of these cells.

Adenocarcinoma↗

PubMed1998

Is laparoscopic radical nephrectomy with specimen morcellation acceptable cancer surgery?

Laparoscopic radical nephrectomy (LRN) for renal-cell carcinoma (RCF) with removal of the specimen by morcellation and suction remains controversial because precise pathologic tumor staging is lost, and there is a risk of tumor seeding. We assessed the theoretical impact of surrendering precise pathologic staging on the management of patients with low-stage RCC (T3a or less). In 22 patients who underwent open radical nephrectomy for RCC, the preoperative CT-based clinical stage was correlated with pathologic tumor staging. Possible clinical inclusion criteria for LRN were then correlated with pathologic tumor staging. When comparing clinical and pathologic staging, one patient was understaged and seven were overstaged by preoperative CT. However, if clinical stage T3a or lower was used as the inclusion criterion for LRN, 19 patients (86%) would have been so treated, none would have been underassigned, and future management would not have been compromised according to pathologic staging. Management of patients with low-stage RCC relying on clinical staging only is oncologically adequate. This would make LRN an acceptable option for this subset of patients.

Carcinoma, Renal Cell↗

PubMed1998

Effect of cholera toxin on intestinal elimination of ciprofloxacin in rabbits.

The transepithelial intestinal elimination of ciprofloxacin (CPX) was studied in cholera toxin (CT)-challenged and control intestinal loops in the rabbit. CPX concentrations were similar in CT-challenged and control jejunal and ileal loops, while cecal elimination was negligible. The quantities of eliminated CPX per square centimeter of bowel wall were significantly higher in the small intestine CT-challenged loops. The mechanism of elimination of CPX in the small intestine is therefore mainly passive diffusion.

Animals↗

PubMed1997

Transurethral needle ablation of the prostate for the treatment of benign prostatic hyperplasia: a collaborative multicentre study.

OBJECTIVE: To assess the efficacy and safety of transurethral needle ablation of the prostate (TUNA) for patients with symptomatic benign prostatic hyperplasia (BPH) in a multicentre trial. PATIENTS AND METHODS: Seventy-six patients were recruited from five centres; all were treated with the TUNA system consisting of a powered radiofrequency generator and a TUNA catheter. The patients were evaluated prospectively using the international prostate symptom score (IPSS), uroflowmetry, quality-of-life score, and other variables, and followed for a mean of 12 months after treatment. RESULTS: Sixty-eight patients were available for follow-up: TUNA produced significant improvements in the IPSS (median 22 before, to 7.5 after treatment). urinary flow rate (mean 8.7 before, to 11.6 mL/s after treatment) and quality-of-life score (median 5 before, to 2 after treatment) at 12 months. CONCLUSIONS: If these early promising results are maintained. In the medium to long term, TUNA therapy will be a useful low-morbidity alternative for patients with symptomatic BPH.

Aged↗

PubMed1997

Suspended pubovaginal fascial sling for the correction of complicated stress urinary incontinence.

OBJECTIVES: Our experience with a modification of the pubovaginal fascial sling technique for the treatment of complicated stress urinary incontinence is reviewed. METHODS: 20 women with complicated stress urinary incontinence underwent suspended pubovaginal fascial sling procedure, with which the sling tension is balanced by combining it with No. 1 Prolene suspension sutures placed at the bladder neck. RESULTS: With a mean follow-up period of 30.7 months, 18/20 patients (90%) were cured of stress incontinence and 2 (10%) were improved. Postoperative complications were minimal, and the voiding dysfunction rate following surgery was 5%. CONCLUSIONS: With a relatively short follow-up we found the suspended pubovaginal fascial sling to be highly successful in the treatment of complicated stress urinary incontinence, with minimal voiding dysfunction and a low complication rate.

Adult↗

PubMed1996

Excretion of ciprofloxacin into the large bowel of the rabbit.

The intestinal elimination of ciprofloxacin in the large bowel was studied in a rabbit model. Segments from the cecum, colon, and sigmoid colon along with their intact blood vessels were isolated and perfused, and their contents were collected over a 90-min period following the administration of a single parenteral dose of 27 mg of ciprofloxacin per kg of body weight. The elimination rates of ciprofloxacin were 0.126 +/- 0.084 micrograms.min-1.cm-2 in the cecum and 0.264 +/- 0.126, 0.11 +/- 0.07, and 0.21 +/- 0.141 micrograms.min-1.cm-2 in the proximal colon, distal colon, and sigmoid colon, respectively. The calculated fraction of ciprofloxacin eliminated in the large bowel was 3% of the parenteral dose administered. The elimination pattern of ciprofloxacin in the large bowel may explain the unusual activity of this fluoroquinolone in modifying the colonic flora.

Animals↗

PubMed1995

Intestinal elimination of sparfloxacin, fleroxacin, and ciprofloxacin in rats.

The intestinal transepithelial elimination of sparfloxacin and fleroxacin was compared with that of ciprofloxacin in a rat model following a single parenteral administration of 25 mg of each of the antibiotics per kg of body weight. All three fluoroquinolones were eliminated through the small intestine. Ciprofloxacin was eliminated in the proximal jejunum at a rate of 1.97 +/- 0.70 micrograms/cm2, while the elimination rates of fleroxacin and sparfloxacin were 0.64 +/- 026 and 0.21 +/- 0.10 micrograms/cm2, respectively, over a 90-min collection period. In the ileum, the elimination rates of ciprofloxacin, fleroxacin, and sparfloxacin over the same period were 1.44 +/- 0.77, 1.00 +/- 0.33, and 0.41 +/- 0.26 micrograms/mc2, respectively. These data suggest that these fluoroquinolones undergo a transepithelial elimination process in the small intestine. This route of elimination may be important in the therapy of bacterial diarrhea.

Animals↗

PubMed1994

Morbidity of radical retropubic prostatectomy following previous prostate resection.

A total of 153 patients with prior prostate surgery underwent a radical retropubic prostatectomy for carcinoma of the prostate. Ninety-seven patients had undergone transurethral resection of the prostate (TURP), and 56 patients had undergone suprapubic transvesical prostatectomy (SPP). In 115 patients, the diagnosis of malignancy was made at the time of transurethral resection or enucleation. No perioperative deaths occurred and no patient suffered rectal injury or ureteral transection. Operative time and blood loss were similar between the TURP and SPP groups and were not different in a group of patients who had not had prior prostate surgery. Early and late complications occurred in eight patients (5.2%), of whom seven had had previous TURP. Complete urinary control was achieved in 96% (147) of the patients; stress incontinence was present in 4% (6 patients); and no patient was totally incontinent. Postoperative complications and the occurrence of stress incontinence were not related to the time elapsed between the previous prostate surgery and the radical prostatectomy. Sexual function was preserved in 32 (71%) of the 45 patients in whom we performed a nerve-sparing radical prostatectomy. Residual cancer was found in the radical prostatectomy specimen in 77 (67%) of the stage A patients. Twenty-nine (25%) of the stage A and 13 (34%) of the stage B patients had pathological evidence of disease extension beyond the confined prostate. Follow-up was 6-92 months, with a mean of 32 months. Four patients died of prostatic cancer, two patients died without cancer, and five have evidence of disease progression; 142 (93%) are alive without evidence of disease. Although radical prostatectomy sometimes is more difficult after previous prostate surgery, operative complication rates, patient morbidity, and the opportunity for surgical cure are not different from those seen in patients with no history of previous prostate operations.

Aged↗

PubMed1994

The intestinal elimination of ciprofloxacin in the rat.

The transepithelial intestinal elimination of ciprofloxacin was studied in a rat model. Two jejunal and one ileal segment, along with their intact blood supplies, were isolated and continuously perfused. Following a single parenteral administration of 25 mg/kg ciprofloxacin, the drug in amounts of 1.97 +/- 0.70, 1.88 +/- 0.99, and 1.44 +/- 0.77 micrograms/cm2 of mucosal surface was recovered over 90 min from the proximal and distal jejunal loops and the ileal loop, respectively, reaching a calculated fraction of 6%-7% of the dose eliminated in the entire small intestine. The rate of intestinal elimination related linearly to the parenteral dose. In the proximal jejunum, however, doses > 25 mg/kg were not accompanied by a concomitant increase in the eliminated fraction, suggesting a saturable transport process. Parenterally administered probenecid, amoxicillin, and nifedipine and changes ranging from 6.0 to 8.5 in the pH of the perfusates did not alter transepithelial elimination. This pathway of elimination of ciprofloxacin may play an important role in curing intestinal infections.

Amoxicillin↗

PubMed1994

Intestinal elimination of ciprofloxacin in rabbits.

The intestinal transepithelial elimination of ciprofloxacin was studied in a rabbit model. Jejunal, ileal, and cecal segments along with their intact blood vessels were isolated and perfused, and their contents were collected over a 120-min period following administration of a single parenteral dose of 27 mg of ciprofloxacin per kg of body weight. The intestinal elimination rates of ciprofloxacin were 0.126 +/- 0.084, 0.235 +/- 0.22, and 0.11 +/- 0.084 micrograms.min-1.cm-2 for the jejunal, ileal, and cecal segments, respectively. The calculated fractions of ciprofloxacin eliminated were 3.3 mg from the jejunum and 13.8 mg from the ileum, representing 19% of the administered dose. Additional amounts of 2.5 to 3.7 mg or 4.9 to 7.3% of the administered dose were eliminated from the cecum. Elimination was probably not due to a passive diffusion process but rather due to an active transepithelial transport. This intestinal elimination pattern of ciprofloxacin may explain the unusual activity of the fluoroquinolones in modifying the intestinal flora.

Animals↗

PubMed1994

Prostate-specific antigen density: a means to enhance detection of prostate cancer.

The ability of serum prostate-specific antigen (PSA) and PSA density (PSAD) to distinguish patients with prostate cancer from those with benign diseases of the prostate was assessed in 495 men. All men were evaluated with PSA determination, digital rectal examination (DRE), transrectal ultrasonography (TRUS) and ultrasound-guided prostatic biopsies. PSA was analysed by the polyclonal (Yang) assay. Prostate volume was estimated from TRUS. PSAD was determined by dividing the serum PSA by the volume of the prostate. Prostatic biopsies identified cancer in 246 of the 495 patients (49.7%). The entire group was divided into 6 subgroups according to PSA level at presentation. Cancer and noncancer patients were compared in each subgroup with respect to the values of PSA, prostate volume and PSAD. For the entire group of patients, there was no statistically significant advantage, for PSAD over serum PSA alone, in distinguishing between benign and malignant prostatic conditions. However, when patients were stratified according to PSA level, PSAD was statistically significantly superior to serum PSA alone in the detection of prostate cancer for PSA values in the intermediate range (2.6-30 ng/ml). This analysis with respect to the DRE and TRUS results showed PSAD to be superior to PSA when both examinations are normal. Our results demonstrate that the influence of PSAD level on cancer detection proportionally increases as the PSAD value increases. Curves constructed from the incidence of prostate cancer according to PSAD values may be useful to select patients with intermediate levels of serum PSA, and normal DRE and TRUS for prostatic biopsies.

Adult↗

PubMed1993

The significance of ureteral obstruction in invasive transitional cell carcinoma of the urinary bladder.

Ureteral obstruction is a frequent complication of transitional cell carcinoma (TCC), known as a poor prognostic sign and indicative of advanced disease. We investigated retrospectively the medical records of 122 consecutive patients who suffered from invasive TCC of the urinary bladder during a 6-year period. Unilateral or bilateral ureteral obstruction was found in 66 patients (54.1%). High stage (T3-T4) and grade (III-IV) tumors were correlated with ureteral obstruction in 89.4% and 83.3% respectively compared to 67.9% and 66.1%, respectively, among patients with normal upper tracts (P < 0.001); 10.6% of the patients with ureteral obstruction had low stage disease, and all of them proved to have involvement of the ureteral orifices on the affected side. The 5-year survival rate of patients with and without ureteral obstruction was 32.2% and 65.9%, respectively (P < 0.001). The presence of ureteral obstruction, particularly in the absence of intravesical involvement of the ureteral orifices, signified a high stage, muscle invasive, and often metastatic tumor in more than 90% of the patients. Ureteral obstruction was an accurate criterion for poor prognostic and was associated with significantly lower, overall and stage-specific, survival rates, despite of radical surgery. We conclude that evidence of ureteral obstruction is an important staging standard and significant prognostic indicator in transitional cell carcinoma of the urinary bladder.

Aged↗

PubMed1993

Massive hematuria due to extramedullary plasmacytoma invading the bladder.

Bladder involvement by extramedullary plasmacytoma is a rare condition. A 46-year-old woman with known IgA-lambda multiple myeloma who developed this condition is described. The patient suffered from massive hematuria, which led to hypovolemic shock. Prompt supportive treatment by blood transfusions, fulguration of the bleeding mucosa and continuous bladder irrigation stopped the bleeding. Subsequent bladder irradiation lead only to partial response of the tumor.

Female↗

PubMed1993

Urinary continence following radical retropubic prostatectomy.

Between 1983 and 1989, 484 men (46-82 years old) underwent radical retropubic prostatectomy for prostate cancer. Six months after surgery, 434 patients (90%) achieved complete urinary control; stress incontinence was present in 50 patients (10%) and no patient was totally incontinent. Of the 398 patients who were followed up for more than 1 year, 377 (95%) achieved complete urinary control and 21 (5%) experienced stress incontinence. Prior open prostatectomy or transurethral resection of the prostate had no influence on the return of urinary control. Pathological stage and preservation or not of the neurovascular bundles also had no significant influence on the long-term state of continence. Age was the only factor that adversely affected the return of urinary continence. The average interval between surgery and return of continence was shorter in patients less than 70 years old. When the impact of age was examined 1 year or more after surgery, no significant difference was noted between the age groups. Several technical considerations that contribute to these results are discussed, especially the use of a gradual approach to the apex of the prostate to facilitate exposure and haemostasis and to preserve as much of the striated urethral sphincter as possible.

Age Factors↗

PubMed1993

Transurethral needle ablation (TUNA) of the prostate using low-level radiofrequency energy: an animal experimental study.

Transurethral needle ablation of the canine prostate using low level radiofrequency energy was examined for efficacy and safety in a two-stage experimental study. Eleven mongrel dogs were treated via the bladder neck and prostatic urethra using a specially designed catheter through which needle antennas were advanced into the prostatic tissue. A radiofrequency energy source was connected to the catheter and used to create tissue ablation. In the first 5 dogs this was found to be feasible. Necrotic lesions were created around the needle antennas. Typically, lesions were 1 cm in diameter and conical in shape. The actual size of the lesion was directly related to power level used, time of ablation and length of needle deployment. In the next 6 dogs temperatures were simultaneously measured in the prostatic urethra and rectum. The dogs were sacrificed 0, 2, 2, 14, 28 and 30 days following the experiments and the bladder, prostate and anterior rectal wall were removed en bloc and examined macroscopically and histopathologically for any changes. It was found that urethral temperatures increased to 46.1 degrees C on the average while rectal temperature did not rise during the entire experiment. The lesions found in the prostate were similar to those found in the first 5 dogs. No macroscopic or histopathologic changes were noted at the bladder base, anterior rectal wall or in the distal prostatic urethra. It was concluded that prostatic tissue ablation in the canine model can be achieved safely and could justify the start of human trials.

Animals↗

PubMed1993

Needle ablation using radio frequency current as a treatment for benign prostatic hyperplasia: experimental results in ex vivo human prostate.

Transurethral needle ablation of the prostate using low level radiofrequency (RF) energy was investigated in a human ex vivo model. RF power applications at a variety of power levels for various treatment times elicited marked thermal lesions of consistent sizes in prostatic adenomas. Tissue temperature was found to be the fundamental lesioning parameter. Lesions were created whenever tissue temperature exceeded 45 degrees C. Lesion size correlated with RF power delivery and electrode length. Monitoring of the tissue impedance assisted in controlling efficacious lesioning. RF power applications of 5-7.5 W for 3 min are suggested as the 'ideal' setting to treat human prostatic adenomas, taking into consideration the lesion size and time to achieve ablative temperatures.

Aged↗

PubMed1993

[Computerization in private urologic practice with multiple practice locations: the use of medical software and a portable microcomputer].

The authors have used a medical programme, Medistory, since June 1990 to computerize a private urological practice. This programme allows personalization of data collection adapted to urology: interview sheets related to the disease, standard report forms, edition of letters, creation of a multi-entry file and entering of accounts. The consultation was always held without a paper support with real-time data acquisition and the accounting was performed at the end of the visit. Letters were printed separately at home, at the end of the day, so as not to delay the patient. A back-up was performed every second day on hard disk. We used a portable Macintosh with 20 mega octets of REM and a 40 mega octet internal hard disk as our practice is based at several sites. This computerisation benefited from the Macintosh interface which facilitated learning and use of the programme. No time loss and no patient discomfort were recorded in comparison with a conventional consultation. The possibility of opening several files at the same time allowed a simple reply to any demands for other information. Two files out of 700 were lost (0.3%) due to an error when saving data. No accounting errors were detected. The use of a medical programme is particularly well adapted to private urological practice with multiple offices. The advantages of a personal computer include the gain of place, rapidity, unlimited storage capacity and the possibility of recovering data with other standard programmes. Medistory, a programme created for general practitioners, is perfectly adapted to this use due to the ease of personalization allowing the creation of interview sheets related to the disease and the edition of reports and various letters.

Computer Security↗