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L Baert

Publications and source records attributed to L Baert.

At least 19 recordsLinked to original sources
PubMed1992

Trisomy 7 and trisomy 10 characterize subpopulations of tumor-infiltrating lymphocytes in kidney tumors and in the surrounding kidney tissue.

We performed conventional cytogenetic analysis and fluorescence in situ hybridization in short-term cultures of normal and neoplastic kidney tissues. Cell populations carrying an extra chromosome 7 or an extra chromosome 10 as the only chromosome change could be identified in kidney tumors, mostly renal cell carcinomas, and in the surrounding kidney tissue, but not in nonneoplastic kidneys. To identify the type of cells displaying these aneuploidies, we performed in situ hybridization (ISH) with probes specific for the centromeric region of chromosomes 7 and 10 on frozen kidney tissue sections. Trisomy 7 and trisomy 10 were restricted to infiltrating inflammatory cells in the tumor as well as in the surrounding tissue. Trisomy 7 and trisomy 10 were also found in subpopulations of peripheral blood T cells of cancer patients and of normal individuals, as well as in the thymus of five normal fetuses (21-29 weeks), but not in noninvaded reactive lymph node sections of patients without malignancy. When lymphocytes were enriched from kidney tumors and surrounding tissue by either Ficoll/Hypaque density gradient or immunomagnetic selection with anti-CD3, anti-CD4, or anti-CD8 monoclonal antibodies, it was confirmed that they contained a high percentage of trisomy 7 and trisomy 10 cells. Further proof for T-lymphocyte origin of the trisomy 7 and trisomy 10 cells was obtained by simultaneous staining of lymphocytes isolated from tumor tissue with anti-CD3, anti-CD4, and anti-CD8 monoclonal antibodies and ISH. We conclude that trisomy 7 and trisomy 10, found in renal carcinomas and surrounding kidney tissue, characterize subpopulations of tumor-infiltrating lymphocytes. The biologic significance of this phenomenon is unknown and requires further investigation.

Chromosomes, Human, Pair 10↗
PubMed1992

Temperature steering in prostate by simultaneous transurethral and transrectal hyperthermia.

Localized hyperthermia (HT) is presently under investigation as a treatment for benign prostatic hyperplasia and carcinoma of the prostate (CaP). One popular approach employs a transrectal (TR) device, a directional microwave (MW) applicator inserted into the rectum and aimed at the prostate. Alternatively, in the transurethral (TU) technique, a symmetrically radiating MW antenna is placed directly within the prostatic urethra. Used individually, TR applicators are capable of effectively heating (> 42 degrees C) the prostate up to 2 cm from the rectum, whereas TU applicators selectively heat the periurethral tissue with effective radial penetration of about 0.6 cm. Neither technique is of much value in heating the anterior prostate. In general, the highest temperatures are produced in the tissue immediately adjacent to the surface of intracavitary microwave devices. However, when MW antennas are used in arrays, the resulting heating pattern can differ significantly from that of the individual antennas. Heating at depth can be selectively enhanced and "steered" by adjusting the phase relationship between the devices. Prostatic temperature profiles were measured in 6 patients treated with TR alone, TU alone, and simultaneous TR and TU heating. In the combined treatments different phase relationships between the antennas were applied. We found that a higher temperature could be produced in the center of the prostate than on the surface of either applicator for certain phase relationships, and that the temperature profiles could be changed by shifting phase. The results of these measurements are in agreement with those of a computer simulation. Based on the above data we feel the combined use of TU and TR hyperthermia may be justified in Phase I-II trials for patients with locally advanced CaP.

Aged↗
PubMed1992

Relationship of response to transurethral hyperthermia and prostate volume in BPH patients.

A response to transurethral microwave hyperthermia (TUHT) at 915 MHz and its relationship to prostate volume was examined in 63 poor surgical risk benign prostatic hyperplasia (BPH) patients. All patients had moderate-to-severe obstructive signs and symptoms, and received > or = 5 TUHT one-hour sessions. Treatment temperature was controlled on the urethral surface at 45 degrees C +/- 1 degree C. Follow-up ranged from twelve to forty-four months (mean 18 months). The mean prostate volume was 57 cc (range 10-301 cc). There were 40 patients (63%) with prostate volume < or = 50 cc and 23 (37%) with a volume > 50 cc. Treatment failure was seen in 6 patients (10%). It was 10 percent in 40 patients with smaller glands and 9 percent for those 23 with larger prostates, N.S. at p = 0.49. Subjective treatment response was seen in 58 patients (92%). It was 90 percent for the 40 patients with < or = 50 cc prostates vs. 96 percent for the 23 with > 50 cc prostates, N.S. at p = 0.75. This study suggests that the initial prostate volume is not an important parameter predicting response to TUHT.

Aged↗
PubMed1992

Electromagnetic extracorporeal shock wave lithotripsy for calculi in horseshoe kidneys.

Between June 1987 and January 1991, 11 renal units in 10 patients with horseshoe kidneys were managed by electromagnetic extracorporeal shock wave lithotripsy (ESWL) monotherapy with a Siemens Lithostar. A total of 33 calculi was treated in 42 sessions. All treatments were performed without anesthesia and on an outpatient basis. All calculi could be targeted by standard installation techniques. The maximum number of shock waves per session was 4,000, which implies per stone an average of 1.3 sessions and an average of 4,903 shock waves (range 1,800 to 9,000) at a mean energy setting of 17.8 kv. Complete disintegration or fragmentation into spontaneously passable particles was achieved in 27 calculi, for a success rate of 83% when considering the results in regard to the individual stone locations. Per renal unit, an average of 3 calculi were targeted and after an average of 3.8 sessions 6 units became stone-free. Horseshoe kidneys, when calculous, contain dispersed and multiple calculi and from these data approximately 1 session per stone must be planned. The number of treatments per renal unit increased in proportion to the number of calculi and to the presence of calculi with low fragility. Of 21 lower pole calculi 18 completely evacuated and this observation has been related to the more medial location of the inferior calices near the ureteropelvic junction. No impaired drainage of fragments was noted to be related to the horseshoe anatomy. Patency of the ureteropelvic anatomy appeared to be the main parameter for the evacuation of fragments. Neither preoperative nor postoperative adjuvant maneuvers have been necessary.

Adult↗
PubMed1992

Whole bladder wall photodynamic therapy with in situ light dosimetry for carcinoma in situ of the bladder.

We report on the preliminary results of 12 patients with multifocal carcinoma in situ of the bladder treated with whole bladder wall photodynamic therapy. The total light dose (scattered plus nonscattered light) measured in situ was 100 joules per cm.2 in the first 6 patients (group 1) and 75 joules per cm.2 in the remaining 6 (group 2). These light doses correspond on the average to 27 joules per cm.2 and 15.5 joules per cm.2 nonscattered light as reported by other investigators. Followup ranged from 6 to 22 months (average 11.5). In group 1, 2 tumors recurred after 6 and 9 months, respectively, and 2 other patients had a permanently shrunken bladder without evidence of disease. In group 2, 1 tumor recurred 5 months after photodynamic therapy. In this group the bladder capacity increased on the average to 135% of the pretreatment value 3 months after photodynamic therapy. All recurrences were in patients with a history of invasive bladder cancer (stages T1 and T2). These preliminary results demonstrate the importance of in situ scattered light dosimetry for minimizing local side effects of whole bladder photodynamic therapy.

Aged↗
PubMed1992

Endovaginal sonography: new diagnostic approach for urethral diverticula.

Too often a urethral diverticulum is a long-standing and unrecognized problem. Suprapubic sonography has been proposed for assessment of this pathological condition. We report on endovaginal sonography as a new improved imaging modality for the diagnosis of urethral diverticula. In positive cases additional morphological information can be obtained from positive pressure urethrography or from diverticulography via fine needle puncture under digital guidance or under sonographic control. Direct puncture of the lesion allows the injection of contrast material to facilitate the diverticulectomy.

Adult↗
PubMed1992

Transurethral hyperthermia for benign prostatic hyperplasia patients with retention.

From 1989 to 1990, 32 poor surgical risk patients with urinary retention were treated with transurethral microwave hyperthermia at the department of urology, University of Leuven in Belgium. Mean patient age was 73 years (range 58 to 90 years) and mean duration of retention was 4 weeks (range 3 to 12 weeks). Followup ranged from 13 to 82 weeks, with a mean of 31 weeks. Bilobar or trilobar hyperplasia was diagnosed in 25 patients (78%), while 7 (22%) had median lobe or median bar hypertrophy. The mean prostatic volume was 52 cc (range 25 to 150 cc). Transurethral microwave hyperthermia was given with a helical antenna at 915 MHz. once or twice per week. The mean number of transurethral microwave hyperthermia sessions was 8.9 (range 5 to 10). Each session consisted of a 60-minute treatment at a mean maximum temperature of 45.4C (range 43.7 to 47.2C), average temperature 43.9C (range 42.7 to 45.5C) and minimum temperature 42.0C (range 40.2 to 43.0C). The temperature was continuously monitored, including thermal mapping in all patients. Of the 25 patients who presented with bilobar or trilobar hyperplasia 18 (72%) were catheter-free for the duration of followup. Of the 7 median lobe or median bar patients 1 (14%) showed sufficient improvement to warrant catheter removal. This patient, however, had recurrent retention 4 months after transurethral microwave hyperthermia. In patients with bilobar and trilobar hyperplasia a strong correlation was observed among maximum temperature (p = 0.0006), average temperature (p = 0.0033) and treatment response. As expected, no such correlation existed between minimum temperature and response to treatment (p = 0.56). Our study has again demonstrated therapeutic activity in patients with benign prostatic hyperplasia treated with transurethral microwave hyperthermia. A new finding was a strong correlation between temperature and response.

Aged↗
PubMed1992

Correlation of extrusion forces, raw materials and sphere characteristics.

This communication reports on the correlation between extrusion forces and sphere characteristics. Dicalcium phosphate dihydrate, alpha-lactose monohydrate and anhydrous beta-lactose were models for respectively an insoluble, a medium soluble and a highly soluble drug and were used to produce spheres. Phase diagrams for ternary mixtures consisting of microcrystalline cellulose, water and a third excipient were constructed. The region where good spheres were obtained correlated well with the area of extrusion forces between 630 and 1260 N. This correlation was seen for the insoluble, the medium and the highly soluble products.

Powders↗
PubMed1992

Effect of alkalinization on calcium oxalate monohydrate calculi during extracorporeal shock wave lithotripsy: in vivo experiments.

Previous in vitro experiments demonstrated the reduced microhardness of calcium oxalate monohydrate (COM) calculi, relative to dry values, when saturated with an alkaline solution (pH = 9.5). Nineteen patients with a COM calculus in the distal ureter which had been resistant to prior extracorporeal shock wave lithotripsy in situ, were treated when the stone was surrounded by alkaline urine. The urine of 14 patients was alkalinized orally by administration of acetazolamine and citrate solution; in 5 other patients direct percutaneous irrigation of sodium bicarbonate via a nephrostomy tube was carried out. The urinary pH just before lithotripsy was greater than or equal to 9 in 17/19 patients. 4,000 shock waves, averaging 18.1 kV generated by the Siemens Lithostar, were delivered onto the calculus. No significant increase of comminution rate was apparent at radiographic control immediately after the treatment and only in half of the cases was evacuation obtained within 3 months.

Bicarbonates↗
PubMed1992

A pseudotumoral edema of the urinary bladder secondary to an intramural impacted ureteral lithiasis.

A case of pseudotumor of the urinary bladder secondary to intramural lithiasis is reported. Computer tomography, cystoscopy of the mass and cytology suggested a malignant tumor. A transurethral biopsy from the tumor was therefore performed, but it showed tissue covered with normal transitional cell epithelium but no signs of malignancy. Pseudotumoral edema of the bladder is easily mistaken for a malignant neoplasm (1, 2, 3).

Aged↗
PubMed1992

Radical prostatectomy for localized prostate cancer.

A retrospective analysis of 70 patients, undergoing a radical prostatectomy in 1989 and 1990 is reported. The value of computed tomography (CT) scanning in preoperative lymph node staging should be reconsidered. Evaluation of the resection margins is of utmost importance as is the distinction between capsular invasion, penetration and transgression. The etiology of local failure and its treatment are discussed.

Adenocarcinoma↗
PubMed1992

Neo-adjuvant hormonotherapy does not facilitate radical prostatectomy.

Sixty-eight patients who underwent radical prostatectomy without or after neo-adjuvant hormonotherapy for B2 or C stage prostate cancer were evaluated as concerned to the ease of the surgical procedure. Although it is difficult to assess this parameter, we experienced more difficulties and blood loss was higher in patients who had preoperative hormonal deprivation. Ongoing randomized trials could demonstrate an oncological benefit of neo-adjuvant hormonotherapy before radical prostatectomy. This eventual benefit will have to be balanced against an increased surgical difficulty.

Aged↗
PubMed1991

Treatment response with transurethral microwave hyperthermia in different forms of benign prostatic hyperplasia: a preliminary report.

During a 7-month period, 79 patients with benign prostatic hyperplasia (BPH) were treated with 915 MHz transurethral hyperthermia (TUHT). All patients had obstructive and irritative signs and symptoms which warranted surgical treatment considerations. Of the 79 patients treated, 31 had follow-ups of 12 months or longer and seven additional patients experienced treatment failure requiring surgical management. These 38 patients were studied to evaluate the relationship of treatment response to the pretreatment prostatic morphology assessed during cystoscopy. There was a well-balanced distribution of patients regarding the important pretreatment characteristics in different morphological types of prostatic hypertrophy. These important characteristics included: prostate volume, postvoiding residual volume, mean peak flow rate, and mean symptom score on the FDA scale. The study patients were scheduled to receive five 60-min TUHT sessions with temperature controlled on the urethral surface at 45.5 degrees C. The treatment were well tolerated and administered on an outpatient basis without sedation or anesthesia. There was a significant difference in the incidence of major improvement in patients with lateral lobe hyperplasia and those with median lobe enlargement, 73 vs. 30%, P = 0.018. From this study, it appears that BPH patients who are found at cystoscopy to have a predominance of median lobe hypertrophy should, perhaps, be selected for treatment other than TUHT. A Phase I study utilizing a modified transurethral applicator to accommodate the specific problem of patients with median lobe hyperplasia is currently being planned.

Aged↗