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M Sade

Publications and source records attributed to M Sade.

16 recordsLinked to original sources
PubMed2005

Localization transition on complex networks via spectral statistics.

The spectral statistics of complex networks are numerically studied. The features of the Anderson metal-insulator transition are found to be similar for a wide range of different networks. A metal-insulator transition as a function of the disorder can be observed for different classes of complex networks for which the average connectivity is small. The critical index of the transition corresponds to the mean field expectation. When the connectivity is higher, the amount of disorder needed to reach a certain degree of localization is proportional to the average connectivity, though a precise transition cannot be identified. The absence of a clear transition at high connectivity is probably due to the very compact structure of the highly connected networks, resulting in a small diameter even for a large number of sites.

Journal Article↗
PubMed2001

Metallothionein expression in renal cell carcinoma: subcellular localization and prognostic significance.

PURPOSE: We investigated the immunohistochemical localization of metallothionein (MT) in renal cell carcinoma and determined the potential role of MT expression as a possible prognostic variable for tumor proliferation and progression. MATERIALS AND METHODS: Tumor tissue blocks from 70 patients with renal cell carcinoma who underwent radical or partial nephrectomy were investigated. Mean followup plus or minus standard error was 36 +/- 3 months. Immunohistochemical testing was performed by the avidin-streptavidin method using a monoclonal mouse antiMT antibody. MT staining intensity in samples was evaluated semiquantitatively. The subcellular distribution of MT was also determined. Staining characteristics were compared with the clinicopathological results. RESULTS: MT immunostaining was found in 39 of 70 tumors (55.7%) and subcellulary MT was localized in the cytoplasm, nucleus and cell membrane. The survival of patients with MT immunostaining was significantly worse than that of those with MT negative results (p = 0.02). A significant relationship of higher tumor grade and MT staining intensity was observed in grades I and III (p = 0.01), and grades II and III (p = 0.02) tumors. No association was found of MT expression and pathological stage. Sarcomatoid tumors showed significantly higher MT expression than clear cell, papillary, granular or chromophobe tumors (p = 0.02, 0.001, 0.01 and 0.01, respectively). MT expression was not an independent prognostic variable. CONCLUSIONS: MT over expression seems to be associated with malignant behavior and poor prognosis in renal cell carcinoma. Therefore, MT expression may be considered a useful marker of less differentiated and more aggressive renal cell carcinoma.

Adult↗
PubMed2000

Giant angiomyolipoma associated with marked pulmonary lesions suggesting lymphangioleiomyomatosis in a patient with tuberous sclerosis.

The association between Tuberous Sclerosis (TS) and Angiomyolipoma (AML) is well known. A patient with TS and giant AML mimicking Renal Cell Carcinoma (RCC), measuring 29 x 18 x 11 cm, weighing 4700 gr is presented. Imaging studies revealed coexistent pulmonary lymphangioleiomyomatosis and concurrent renal and pulmonary involvement is extremely rare in patients in TS. We believe that the growth potential of this hamartomatous lesion may reach to a life threatening size.

Adult↗
PubMed2000

Prognostic significance of microvascular invasion in localized renal cell carcinoma.

OBJECTIVES: The treatment of localized and even advanced renal cell carcinoma (RCC) is radical nephrectomy. However, 30% of these patients progress after radical nephrectomy. Prognostic factors are needed in order to determine the course of disease in patients undergoing radical nephrectomy. The aim of this study is to study the prognostic significance of microvascular invasion (MVI) in patients who had undergone radical nephrectomy for localized RCC. METHODS: Between June 1989 and February 1999, pathologic sections of the specimens from 41 patients without metastases, nodal involvement or macroscopic venous involvement were investigated for MVI. RESULTS: MVI was observed in 17% of the patients. MVI was related to the grade of the tumor and tumor size (p = 0.032, p = 0.017). In sarcomatoid-type RCC, MVI was more common than in other histologic types (p = 0.003). After a median follow-up of 48 months, the progression rate was 29% in patients with MVI and 17% without MVI (p = 0.001). Median progression time was 3 months in those with MVI and 41 months with no MVI (p = 0.01). The survival rate decreased from 85 to 70% in patients with MVI during a median follow-up of 48 months (p = 0.031). In multivariate analysis, MVI was not found to be an independent prognostic factor. CONCLUSION: Although MVI is closely related to progression and prognosis, in multivariate analysis it was not found to be an independent prognostic factor in localized RCC. We conclude that MVI should also be evaluated together with tumor grade in predicting the prognosis of patients with localized RCC.

Blood Vessels↗
PubMed1998

Volume-weighted mean nuclear volume in renal cell carcinoma.

OBJECTIVES: Tumor grade and stage are the most important prognostic parameters for renal cell carcinoma (RCC). The value of histologic nuclear grading, however, is impaired by the inconsistency of pathologists' observations. Estimate of volume-weighted mean nuclear volume (MNV), based on a stereologic method, is correlated with prognosis of bladder, prostate, and endometrial cancer. In this study, we investigated the prognostic value of stereologic estimation of nuclear volume in RCC. METHODS: This study included 62 patients with RCC who underwent radical nephrectomy between 1989 and 1996. Patients were evaluated in two groups: patients with locally advanced and/or metastatic disease were part of the poor prognosis group and patients with localized disease were part of the good prognosis group. Unbiased estimates of MNV were compared with histologic grade, tumor stage, and growth pattern according to Thoenes classification. Group means were compared using the nonparametric Kruskal-Wallis one-way analysis of variance. Univariate analysis of the data was performed for MNV and time to death, metastasis, local recurrence, and disease-free survival by paired sample t test. For categorical variables, Pearson's correlation test was used for statistical analysis. RESULTS: There was no correlation between MNV and patient sex, age, tumor stage, and growth pattern. MNV showed a trend to be higher in sarcomatoid and chromophilic cell types than in chromophobe and clear cell types (P < 0.05). MNV values were significantly higher with increasing grades but no MNV cutoff levels could be defined. The MNV values were not different between localized and locally advanced and/or metastatic disease. CONCLUSIONS: Our results indicate that estimates of MNV are not useful for predicting disease outcome. Further studies are needed to set up reproducible intervals of tumor dedifferentiation that could be carried out in routine practice for predicting progression.

Adult↗
PubMed1998

Renal effects of carbon dioxide insufflation in rabbit pneumoretroperitoneum model.

To determine the effects of carbon dioxide insufflation on renal function in a pneumoretroperitoneum model, 24 adult New Zealand rabbits were divided into four groups, six rabbits in each. The first group underwent a 2-hour CO2 insufflation at a pressure of 10 mm Hg in the retroperitoneal space after balloon dissection. In another group, the same procedure was maintained for 4 hours. In the sham-treated groups, the procedure was similarly carried out but without CO2 insufflation. In all four groups, serum and urine creatinine concentrations and renal artery and renal vein blood flow rates were determined separately at the beginning and at the end of the procedure and at 24 hours. Urine output was also recorded at the end of the procedure and at 24 hours. The serum creatinine in the 2- and 4-hour study groups had increased significantly at the end of the procedure, accompanied by a significant decrease in the urine creatinine value. Renal artery and renal vein blood flow rates and urine output were reduced in both groups during the study. All changes in the serum and urine creatinine, renal artery and vein flow rates, and urine output was more pronounced in the 4-hour group. All measures returned to their prestudy values by 24 hours. Pneumoretroperitoneum causes reversible renal dysfunction, which becomes more pronounced with prolonged insufflation. Further research is needed to show the impact of our findings in high-risk patients undergoing retroperitoneoscopic surgery.

Animals↗
PubMed1998

Is magnetic resonance imaging necessary in the staging of prostate cancer?

OBJECTIVE: To evaluate the necessity of using magnetic resonance imaging (MRI) in the staging of patients with clinically localized prostate cancer. METHODS: Sixty-one patients with prostate cancer were evaluated with MRI for preoperative staging with a conventional body-coil (Siemens Magnetom, 1.0 Tesla superconducting system). Twenty-nine patients underwent radical prostatectomy for presumed clinically localized disease. Of those, 17 were staged both with MRI and computerized tomography (CT). The remaining patients were staged with CT alone. MRI and CT findings, and the final pathologic staging of patients are reviewed. RESULTS: On pathological examination of the surgical specimens, the tumor was found to extend beyond the prostate in 7 patients (41%). Among the 17 patients who were operated, extraprostatic extension (EPE) was detected accurately in 3 patients with MRI (sensitivity 20%, specificity 92%, accuracy 70. 5%). No metastatic lymph nodes were detected on the basis of MRI (sensitivity 0%, specificity 93%, accuracy 88.2%). In 1 patient EPE was correctly identified by CT (sensitivity 14%, specificity 100%, accuracy 64.7%). CONCLUSION: Neither MRI with conventional body-coild nor CT are sufficient to indicate local extension of disease in clinically localized prostate cancer.

Aged↗
PubMed1995

[Multidisciplinary approach to counseling in Huntington's disease].

The recent cloning of the Huntington's disease gene now allows definitive presymptomatic and even prenatal testing. This achievement has posed a considerable challenge for the genetic counselor. We present the multidisciplinary approach implemented in our center, and experience in our first 13 diagnoses. Individuals at risk undergo neuropsychiatric evaluation, genetic counseling, molecular studies, post-counselling follow-up and support according to the protocols suggested by the International Huntington's Disease Association. Molecular studies of cytosine-arginine-guanine repeats showed that 4 individuals and 1 at-risk fetus were unaffected and 6 at-risk individuals, including the mother of the fetus, had inherited the disease mutation. The diagnosis was excluded in 2 individuals clinically suspected of Huntington's disease. All but 1 of those investigated had accepted, and adapted to the new reality. The exception was a carrier who asked to discontinue the contact a week after being informed of the results.

Clinical Protocols↗
PubMed1994

Does respiratory gating improve extracorporeal shockwave lithotripsy results?

The reliability and efficacy of extracorporeal shockwave lithotripsy (SWL) has been established in urinary stone disease. Its combination with respiratory gating might be a useful method to increase the effectiveness of treatment and reduce the number of shocks required. For this purpose, the results of SWL combined with respiratory gating were compared with those of SWL without gating. There was no difference in the stone-free rates of the two groups or in the complication rate. It is concluded that this method neither decreases the number of shockwaves needed nor increases the effectiveness of SWL.

Adult↗
PubMed1988

The effect of testicular torsion on the contralateral testis and the value of various types of treatment.

In an attempt to investigate the effect of testicular torsion and various forms of treatment on the contralateral testis, an experimental study on rats was undertaken. The first group comprised control animals. In the second group the left testes were twisted 720 degrees and the right testes were removed 4 weeks later for histopathological examination. In the third group the rats were subjected to a left detorsion procedure 24 h after torsion, while in the fourth group cortisone treatment was added to the above procedure. The fifth group consisted of rats which had undergone left orchiectomy 24 h after torsion and the sixth group had cortisone treatment plus orchiectomy after torsion. Cortisone treatment was started 24 h after testicular torsion and continued for 4 weeks. Histopathological examination of the contralateral testes which were removed 4 weeks later showed that either orchiectomy plus cortisone or detorsion plus cortisone was more successful than other forms of treatment.

Animals↗
PubMed1987

Effect of testicular torsion on the contralateral testis and prevention of this effect by prednisolone.

This study was instituted to evaluate the effect of unilateral testicular torsion on contralateral testicular histology and the prevention of this effect by prednisolone. Fifty Swiss albino rats were equally divided into 5 groups. In group 1, it was observed that, due to torsion, the mean seminiferous tubular diameter and percentage of spermatogenetic activity of the contralateral testes were reduced and an inflammatory reaction was also noted. In group 2, detorsion increased the above-mentioned damage, and in group 3, orchiectomy failed to prevent it. In group 4, it was seen that prednisolone slightly increased the mean percentage of spermatogenetic activity and produced proliferation of the Leydig cells in the intact testicle. In group 5, when prednisolone was injected just after torsion, no damage to the contralateral testes appeared. It has been thought that damage to the contralateral testes may arise from an autoimmune mechanism and prednisolone appeared to be very helpful in preventing damage by immunologic suppression.

Abscess↗
PubMed1984

Reduced activities of triple adenosine triphosphatase in seminal plasma and spermatozoa of patients with oligoasthenospermia.

Na+- and K+-activated and Mg2+-dependent adenosine triphosphatase, Mg2+-activated adenosine triphosphatase and Ca2+- and Mg2+-activated adenosine triphosphatase activities were determined in washed spermatozoa and in two fractions (pellet and supernatant) of seminal plasma of oligoasthenospermic patients and men with normal spermiograms. The activities of triple adenosine triphosphatase oligoasthenospermics were significantly lower than those of normals. The morphologic features of spermatozoa of oligoasthenospermics were of normal standards. Possible explanations for the significantly lowered triple adenosine triphosphatase activities from patients with oligoasthenospermia are given with special reference to the ion transport functions of the triple adenosine triphosphatase enzyme system.

Adenosine Triphosphatases↗
PubMed1978

The management of azoospermia.

Azoospermia in the presence of a normally functioning testis and a normal vasogram has been thought to be due to an obstruction in the epididymis between the body and the head. However, bypass operations have been singularly unsuccessful except when there was evidence of past inflammation causing fibrosis of the body and tail of the epididymis. Two substances, glycerylphosphorylcholine and carnitine, which are known to be secreted by the epididymis, were investigated. The results of this preliminary study suggest that they may play a part in the management of patients presenting with azoospermia.

Carnitine↗
PubMedDate not supplied

The effect of zinc, arginine, fructose and seminal supernatant of normal semen on the triple adenosine triphosphatase activities of the spermatozoa from males with oligoasthenozoospermia.

When the spermatozoa of oligoasthenozoospermic patients were suspended with the supernatant of normal semen, an increase in triple ATPase enzyme activities besides enhancement of spermatozoa motilities were observed. This suggests that factor or factors present in the supernatant of normal semen that effects spermatozoa motility also have a positive effect on triple ATPase enzyme activities. In an attempt to produce such an effect, zinc, arginine and fructose were added to the incubation media where the spermatozoal ATPase enzyme activities were determined. Zinc increased Ca2+-Mg2+ ATPase enzyme activity without affecting Na+/K+-Mg2+ and Mg2+ ATPase activities. Triple ATPase enzyme activities remained unchanged after arginine and fructose additions. As a result zinc is thought to be one of the factors that affect spermatozoa motility in seminal plasma.

Adenosine Triphosphatases↗