Biomedical subjects

Yoram Dekel

Publications and source records attributed to Yoram Dekel.

13 recordsLinked to original sources

PubMed2005

The Heilbronn laparoscopic training program for laparoscopic suturing: concept and validation.

BACKGROUND AND PURPOSE: More than a decade after the first description of laparoscopic nephrectomy, an increasing number of laparoscopic procedures are being performed worldwide. Nevertheless, there still exists a significant lack of standardized training programs to teach ablative and, most important, reconstructive laparoscopic operations (i.e., pyeloplasty, radical prostatectomy). We evaluated and validated a new standardized step-by-step program to improve laparoscopic skills and enable trainees not experienced in laparoscopy to perform a urethrovesical anastomosis. MATERIALS AND METHODS: In an inanimate model (pelvic trainer) with defined trocar positions, the 10 participants were exposed to six reconstructive exercises. The steps consist of improvement of hand-eye coordination (two-row metal-pin model; step I), linear and curved suturing with changing angles of the needle (chicken leg and catheter model; steps II-V), and performance of an anastomosis in a porcine bladder (step VI). Times of 3, 15, 15, 10, 20, and 30 minutes for steps I, II, III, IV,V, and VI, respectively, were defined as the goal before proceeding to the next stage. The time required to succeed in each step and the increase in the speed of suturing and knotting activities were analyzed with the Wilcoxon signed-rank test. RESULTS: After a mean of 40 hours of training, all participants were able to perform all steps within the specified times and complete an accurate urethrovesical anastomosis in 30 minutes. The time required to succeed before and after training showed a significant decrease (P < 0.05). Continual training in reconstructive procedures decreased the time needed for suturing activities by between 66.3% and 72.2%. The time needed for the knotting activities decreased by between 34.3% and 38.3%. CONCLUSIONS: Our program enabled participants not experienced in laparoscopy to increase reproducible performance in reconstructive laparoscopy. These results indicate that the challenging parts of reconstructive laparoscopy such as intracorporeal suturing can be taught using a standardized concept. This experience could be incorporated easily by every department developing a laparoscopic training program.

Anastomosis, Surgical↗

PubMed2005

Assessment of vesicoureteral reflux in patients with self-retaining ureteral stents: implications for upper urinary tract instillation.

PURPOSE: Conservative treatment of upper urinary tract tumors has been popularized during the last decade. Like in bladder cancer management, localized adjuvant therapy has been advocated to reduce the risk of disease recurrence or progression. In this study we tested the feasibility of creating vesicoureteral reflux (VUR) using a Double-J stent (Medical Engineering Corp., New York, New York) as a measure of efficacy for intravesical adjuvant treatment of the ureter and renal collecting system. MATERIALS AND METHODS: The cohort included 100 consecutive patients in whom a Double-J stent was inserted for renal obstruction. All the patients underwent cystography in the supine position by retrograde filling of the bladder with a 50% dilute solution of 300 mgI/ml iopromide in serial increments of 50 ml up to a maximum of 350 ml. A total of 41 patients underwent cystography immediately following stent insertion (early group) and 59 patients with indwelling stents underwent cystography before further endourological intervention (late group). The presence of VUR and the level along the ureter and renal collecting system were assessed fluoroscopically. RESULTS: Overall VUR was detected in 56 patients (56%), specifically 11 of the 41 (27%) in the early group and 45 of the 59 (76%) in the late group (p <0.001). There was no correlation between stent diameter or length and VUR, or between patient sex, age or particular side and the likelihood of reflux. Mean minimal intravesical volume required to obtain reflux was 171 +/- 11 ml, which was significantly higher in the early (255 +/- 21 ml) than in the late (146 +/- 11 ml) cystogram group. In 24 of the 56 patients (43%) with VUR, there was complete visualization of the entire ureter and renal collecting system. However, 15 patients (26%) had opacified renal pelves and calices without concomitant visualization of the ureters, whereas 7 patients (31%) had reflux to the ureter without opacification of the renal pelvis. CONCLUSIONS: VUR is not a guaranteed consequence of Double-J stent placement. Therefore, when upper urinary tract instillation with the Double-J technique is considered, a cystogram should be performed first to confirm the occurrence of reflux, determine the intravesical volume required to induce reflux and ascertain that the pertinent section of the ureter or pelvicaliceal system from which the tumor was initially removed is opacified during study. An interval that remains to be defined should be allowed between stent insertion and VUR assessment.

Administration, Intravesical↗

PubMed2005

Human DNA topoisomerase II-alpha expression in laparoscopically treated renal cell carcinoma.

To investigate whether the expression of Topoisomerase II-alpha (TII-alpha) can serve as a prognostic factor in renal cell carcinoma (RCC), histological sections from 27 renal tumors were stained immunohistochemically for TII-alpha expression. The percentage of positive cells in the area of greatest staining was recorded as the TII-alpha index. TII-alpha nuclear staining was positive in all the samples except one. The mean TII-alpha index was 12.5 for grade 1, 44 for grade 2 and 113 for grade 3 tumors. The mean TII-alpha index was 22.3 in tumors which did not recur and 81 for tumors which recurred during the follow-up period. In this study, a higher TII-alpha index correlated with more aggressive tumor behaviour. However, a large cohort of patients should be assessed before drawing definitive conclusions.

Adult↗

PubMed2004

Talc inhalation is a life-threatening condition.

A case of rapidly progressive disease and pulmonary hypertension due to chronic cosmetic talc inhalation is presented. Although an uncommon cause of pulmonary hypertension, talc, especially through intravenous administration, should be included in the etiology of parenchymal pulmonary hypertension. In our case talc inhalation was inadvertent, causing fulminant disease leading to the patient's death. To our knowledge, this is the first case of inadvertent talc inhalation causing death in adult patient.

Adult↗

PubMed2004

Expression of protein kinase C isoenzymes in benign hyperplasia and carcinoma of prostate.

Protein kinase C family consists of 11 isoforms, classified into 3 categories according to their structure and mechanisms of activation. These isoenzymes are involved in processes, which maintain intracellular homeostasis. Alterations in activity, amount or distribution of protein kinase C (PKC) isoenzymes may cause cellular proliferation or induce apoptosis. We have studied and compared the expression levels of several PKC isoforms in benign prostatic hyperplasia (BPH) and prostate cancer (PCa). These are PKCs alpha (alpha), beta (beta), delta (delta), epsilon (epsilon), zeta (zeta), eta (eta), which have been detected as major isoforms in prostate tissue. Paraffin sections of 25 benign prostatic hyperplasia (BPH) and 25 of prostatic carcinoma (PCa) were examined for expression of PKC alpha, beta, delta, epsilon, zeta, and eta. Expression of PKC beta was examined in additional 3 BPH and 3 PCa using Western blot analysis. We found a significant high level of expression of PKC isoforms alpha, beta, epsilon and eta in PCa compared to BPH (p<0.01). Using backward logistic regression, we found changes in PKC epsilon expression to be most significant between malignant compared to benign tumor tissue specimens. Immunostaining for PKCs alpha, beta and eta in addition to PKC epsilon may aid in distinguishing between benign and malignant prostatic disease.

Aged↗

PubMed2004

Quantitative microscopy of human DNA topoisomerase II-alpha expression in transitional cell carcinoma of the bladder.

OBJECTIVE: To compare the nuclear size of various grades of transitional cell carcinoma (TCC) stained immunohistochemically with the nuclear enzyme topoisomerase II-alpha (topo II-alpha) in bladder urothelial neoplasms. STUDY DESIGN: Histologic sections from 53 consecutive papillary bladder neoplasms were stained immunohistochemically for topo II-alpha expression. There were 18 (33.9%) urothelial neoplasms of low malignant potential (UNLMP), 18 (33.9%) low grade urothelial carcinoma (LGUCa), and 17 (32%) with high grade urothelial carcinoma (HGUCa). The histologic slides were photographed at 400 x magnification and then projected on a screen, and the area with stained nuclei was measured. RESULTS: The cells and nuclei in HGUCa were significantly larger than in LGUCa (P < .05) and UNLMP (P < .01). CONCLUSION: Calculation of the area fraction of nuclei in TCC of the bladder stained with topo II-alpha is an additional method of establishing the grade of these tumors.

Adult↗

PubMed2003

The expression of DCC protein in female breast cancer.

BACKGROUND: The deleted in colorectal cancer (DCC) gene has been shown to be frequently deleted or its expression reduced or absent in glioblastomas, colorectal, gastro-intestinal, pancreatic and prostatic tumors. In the present study, we investigated the expression of DCC in surgical specimen from 75 patients with primary breast cancer. METHODS: The expression of the DCC, estrogen receptors (ER), and progesterone receptors (PR) was studied in 75 surgical specimens of primary breast cancer using an immunohistochemical method. To evaluate the outcomes of the breast cancer patients, we followed up the patients during minimum of 10 years. RESULTS: Reduced or loss of expression of DCC was identified in 45 out of 75 samples. There were significant differences between cases without metastasis or local recurrences versus these with metastasis or local recurrences (p = 0.006), and between patients alive with no evidence of malignancy versus those with recurrence or dead of disease (p = 0.005). There were no significant differences between the DCC status and age, sex, tumor location, stage, grade, or proportion of patients who received adjuvant therapy. CONCLUSIONS: These findings suggest that a decrease in DCC expression may influence the prognosis of breast carcinoma patients.

Breast↗

PubMed2003

Combined intravesical hyperthermia and mitomycin chemotherapy: a preliminary in vivo study.

Previous clinical studies of the combination of local intravesical hyperthermia with cytostatic drugs for the treatment of Superficial Transitional Cell Carcinoma of the urinary bladder (STCCB) showed encouraging results both in reducing recurrence rate to 20-30% within 2 years and in ablative success rate of 79%. Our objectives were to evaluate bladder tissue and adjacent organs during and following hyperthermia treatment. An intravesical catheter equipped with a radio-frequency antenna (Synergo SB-TS 101.1 System) was used for hyperthermia and intravesical chemotherapy (mitomycin C) was instilled in vivo for 60 min in two anaesthetized sheep. Thirteen to fifteen thermocouples were sewn surgically on the internal and external surfaces of the bladder wall and on adjacent organs to monitor the temperature during the treatment. We expected the intravesical temperature to be under 46 degrees C and the external layers below 45 degrees C. The bladder was filled with 50 mL of chemotherapeutic solution (400 micro g/mL of mitomycin C in distilled water). The sheep were sacrificed at the end of the treatment. Three other sheep, which underwent thoracic surgery, served as control group. Histological changes in both groups showed foci of oedema and haemorrhage with inflammation in the lamina propria and serosa. Foci of desquamation of the epithelium were noticed in the treated sheep. Histological analysis of the treated group showed no significant differences from the control group. The control group showed similar changes, some less pronounced. The combined treatment of hyperthermia with mitomycin C did not cause major damage to the urinary bladder or adjacent organs. All changes were superficial and reversible, and the control group showed similar changes, some less pronounced. Although this is an experimental model based on one single session treatment, rather than repeated treatments, it suggests that the approach may be useful in future studies both in models and man.

Adipose Tissue↗

PubMed2003

Unusual splenic metastasis from renal cell carcinoma. A case report and review of the literature.

This is a short report on a splenic metastasis from renal cell carcinoma. Previously, the patient had renal carcinoma removed by nephrectomy. The diagnosis of metastasis was based on morphology and immunohistochemistry. It is certainly true that splenic metastases from renal cell carcinoma are rare. Nevertheless, they have been well described in the literature. A giant cell reaction to tumor is noted in a number of cancers and mainly represents an unusual phenotype.

Aged↗

PubMed2002

Significance of angiogenesis and microvascular invasion in renal cell carcinoma.

The aim of this study is to evaluate the relationship between tumor angiogenesis and microvascular invasion, and the subsequent development of metastatic disease in patients undergoing surgery for renal cell carcinoma (RCC). The study group consisted of 102 patients who underwent surgery for RCC between the years 1990 and 1997 in our institute with a mean follow up period of 81.3 months. Paraffin blocks were stained for Factor VIII - related antigen and CD34 which decorate endothelial cells in order to assess angiogenesis and microvascular invasion and their relevance for developing metastatic disease. When Factor VIII- related antigen staining was used we found that the microvessel count correlated with the development of metastatic disease with a mean count of 49.7 for patients with no evidence of disease and a mean count of 95.5 for patients who developed metastatic disease (p<0.05). We also found that microvascular invasion correlated with the development of metastatic disease. It was demonstrated in 55.5% of patients who developed metastatic disease versus 23.8% of patients with no evidence of disease with Factor VIII staining (p<0.05), and in 33.3% and 7.1%, respectively (p<0.05) with CD34 staining. This study suggest that demonstration of intense angiogenesis and micro-vascular invasion may be a predictor of a more aggressive tumor mandating closer follow up and consideration of adjuvant therapy.

Aged↗

PubMed2002

Renal cell carcinoma in pregnancy.

Renal cell carcinoma is a rarely reported neoplasm in pregnancy. The pregnancy demands special consideration in terms of the diagnostic evaluation and management. Two patients with renal cell carcinoma who presented during the second trimester of pregnancy and underwent radical nephrectomy are reported with a review of published studies. It seems that because the mother's welfare is the primary concern, surgical management need not be delayed.

Adenocarcinoma, Clear Cell↗

PubMed2002

Periappendiceal actinomycosis mimicking malignancy report of a case.

A case of a periappendiceal actinomycosis, seen in an 83-year-old woman, clinically mimicking a right ovarian neoplasm penetrating the right colon, is presented. The patient's complaints led to the discovery of a right abdominal mass. Explorative laparotomy and right hemicolectomy were done. Histological examination revealed periappendiceal actinomycotic abscesses. We discuss a possible pathogenesis and the therapeutic modalities.

Abscess↗

PubMed2002

The spectrum of laryngeal neoplasia: the pathologist's view.

Several types of neoplastic change with different prognostic implications typically involve the laryngeal squamous epithelium. The purpose of this review is to examine the spectrum of these changes, as well as their relationship to benign squamous epithelial proliferative states. Since these pathological changes are apt to occur in regions where the epithelial lining is typically squamous, it is important to recognize that the epithelium of the larynx varies from stratified squamous to respiratory-type, depending on the location. The lingual (anterior) surface of the epiglottis is lined by a stratified squamous type, while the laryngeal (posterior) surface is stratified squamous merging into respiratory-type. In the larynx, the supraglottic and infraglottic portions are a respiratory-type, which contrasts with the stratified squamous epithelium of the glottis. This typical distribution does show some degree of variability in those patches of squamous epithelium and is frequently seen within the respiratory-type epithelial regions. The junction between the two epithelial types may be abrupt or separated by a transitional zone.

Carcinoma in Situ↗