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R Hamza

Publications and source records attributed to R Hamza.

At least 37 records · Page 2Linked to original sources
PubMed1997

Expression of cyclin D1, but not cyclins E and A, is related to progression in bilharzial bladder cancer.

The present study was conducted to analyze the alterations affecting cyclins D1, E, and A in bilharzial bladder cancer and to assess their potential clinical significance. A total of 125 cases were examined. Histopathological subtypes included 68 squamous cell carcinomas, 55 transitional cell carcinomas, and 2 adenocarcinomas. Immunohistochemical analyses were performed using a panel of well-characterized antibodies. The results were correlated with proliferative index, as assessed by Ki67 antigen expression. The cyclin D1-positive phenotype, defined as the identification of positive immunoreactivity in the nuclei of >/=20% of tumor cells, was found in 33 of 107 (31%) evaluable cases. A significant association was observed between the cyclin D1-positive phenotype and deep muscle invasion (P = 0.02), high tumor grade (P = 0.02), and Ki67 high proliferative index (P = 0.03). The cyclin E-positive phenotype, defined as per cyclin D1, was found in 79 of 106 (75%) evaluable cases. The cyclin A-positive phenotype, defined using the above criteria, was identified in 60 of 108 (56%) evaluable cases. No statistically significant association was found between cyclins E or A and clinicopathological parameters or proliferative index. However, there was a strong association between the expression of cyclin D1 and the coexpression of cyclins A and/or E (P = 0.05). Ki67 proliferative index was considered high when >/=20% of tumor cells displayed positive nuclear staining, a phenotype that was observed in 99 of 115 (86%) cases. These data support the hypothesis that cyclin D1 activation determines the evolution of a particular subset of aggressive bladder tumors. In addition, cyclins E and A seem to follow an unscheduled pattern of expression, based on the high frequency of identifying a positive phenotype for these cyclins and the lack of correlation between their expression and Ki67 high proliferative index. It may be postulated that the expression of G1 cyclin genes is deregulated in bilharzial bladder cancer, and that cyclin D1 acts as an oncogenic event in these neoplasms. Moreover, the moderate number of tumors displaying the cyclin D1-positive phenotype (31%) versus the high frequency observed for both cyclins E (75%) and A (56%), suggests a short G1 disbalanced by a long S phase and a rapid transversal of the cell cycle, as evidenced by a high Ki67 index observed in 86% of these cases. This imbalance in the cell cycle, together with alterations reported on the p53 pathway, might underline the accumulation of DNA damage and the aggressive clinical course of bilharzial bladder cancer.

Adenocarcinoma↗
PubMed1997

Alterations affecting the p53 control pathway in bilharzial-related bladder cancer.

Bilharzial-related bladder carcinoma (BBC) is the most common malignant neoplasm in Egypt, also occurring with a high incidence in other regions of the Middle East and East Africa. The clinical and pathological features of BBC are different than those described for the conventional transitional cell carcinoma of the bladder, including the high incidence of squamous cell carcinoma reported in BBC and the fact that over 90% of BBC cases at presentation are advanced-stage tumors (P3 and P4). This study was conducted to better define the phenotypic alterations associated with BBC affecting the p53 cell cycle control pathway, including altered patterns of expression of downstream effector proteins such as mdm2 and p21/WAF1. A well-characterized cohort of 125 patients affected with bilharzial-related bladder tumors was studied. Tumors were classified as squamous carcinomas (n = 68), transitional cell carcinomas (n = 55), or adenocarcinomas (n = 2). The products encoded by TP53, mdm2, and p21/WAF1 genes were analyzed by immunohistochemistry. Furthermore, the patterns of expression of these molecules were correlated with the Ki67 proliferative index. In addition, the microanatomical distribution of programmed cell death was assessed in a subset of tumors, using the so-called terminal deoxynucleotidyl transferase-mediated nick end labeling method. p53 nuclear overexpression was identified in 25 (20%) of 125 cases. Nuclear overexpression of mdm2 was detected in 74 (59.2%) of 125 cases. There was a statistically significant association between coexpression of both p53 and mdm2 and detection of lymph node metastases (P = 0.04). p21/WAF1 expression was detected in 87 (72%) of 121 evaluable cases. A high Ki67 proliferative index was observed in 99 (86%) of 115 evaluable cases. There was a statistically significant association between high Ki67 proliferative index and mdm2-positive phenotype (P = 0.005) and deep muscle invasion (P3b; P = 0.026) as well as lymph node metastases (P = 0.039). Apoptosis was observed in terminally differentiated tumor cells identified in the superficial layers of well-differentiated squamous carcinoma or exfoliating cells in transitional lesions. However, only rare apoptotic tumor cells were found in basal or suprabasal layers as well as in the invasive elements of the neoplasms studied. These results suggest that the frequency of p53 nuclear overexpression in BBC is lower than that reported for conventional transitional cell carcinoma. Nevertheless, tumors with p53 alterations have a greater propensity to progress. The prominent number of cases displaying an mdm2-positive phenotype suggests that this may be an early incident in BBC and should be regarded as a potential oncogenic phenomenon. This is supported by the significant correlation between high Ki67 proliferative index and mdm2 overexpression. The association of an aggressive clinical course with the coexpression of both p53 and mdm2 products might be viewed as a cooperative effect that develops in tumor progression.

Adenocarcinoma↗
PubMed1996

[Pseudotumoral abdominal cysto-steato-necrosis: an unusual etiology].

We report an unusual case of subcutaneous pseudo-neoplastic focal fat necrosis in a woman with a Mersilen plate placed outside the abdominal wall muscles. To our knowledge, this association has not been previously reported in the radiologic literature. The differential diagnosis using ultrasound and computerized tomography is discussed.

Abdominal Muscles↗
PubMed1995

[Value of the "Dentascanner"al in dento-maxillary diseases (infectious and cystic)].

MATERIAL AND METHODS: From July 1993 to April 1994, forty dentascans were performed at Bicetre Hospital, on an Elscint Elite Plus scanner for: chronic sinusitis (18 cases); cystic pathologies (8 cases); pre-operative assessment for dental implantation (14 cases). RESULTS: Dentascan images permitted a precise analysis of dentomaxillary anomalies. In all cases they demonstrated the anatomical relationships of the lesions, permitting a determination of potential complications. In chronic sinusitis dental pathology was demonstrated including peri-apical granulomas or cysts breaks or elevations of the floor of the maxillary sinus, malplaced dental filling material in the maxillary antrum and fistula tracks. Among the 14 pre-operative assessments, four cases of infectious lesions were demonstrated, thereby counter-indicating dental implantation. CONCLUSION: The dentascan appears to be very useful for dentomaxillary pathology by facilitating diagnosis and the formulation of treatment and operative strategies.

Chronic Disease↗
PubMed1995

[Rare causes of ossification of the posterior common vertebral ligament causing cervical compression. Apropos of 2 cases].

The ossification of the posterior longitudinal is always responsible of cervical myelopathy. Radiological study and the CT scan, are able to precise the level, the morphologic and associated abnormalities of this lesion. Two cases of ossification of the posterior longitudinal ligamentum with cervical myelopathy are reported. The radiologic studies determined the etiology, in the first case, it was fluorosis and the second DISH disease.

Aged↗
PubMed1994

[Uncommon etiology of cruralgia].

A 58 year old man suffered from low back pain. Physical examination showed asymmetry of the quadriceps and slight motor deficiency of right leg. Plain radiography of the pelvis revealed a large osteophyte, developed anteriorly at the low part of the right sacro iliac joint. CT exam of lumbar spin was normal. But, it confirmed osteophyte of right sacro iliac. Percutaneous injection of a small quantity of xylocaine under CT guidance in the site of the osteophyte behind crural muscle was marked by immediate disappearance of the pain, confirming the site of conflict between the crural nerve and the osteophyte. The patient was treated by injection of corticosteroid at the same location. Recovery was good.

Femoral Nerve↗
PubMed1993

[Pulmonary emphysema: quantification using computed tomography and correlations with respiratory function tests].

Pulmonary emphysema can be defined in precise anatomical terms. Only histological examination of an entire lung will enable the extension and the severity of the emphysema to be fully assessed. The authors propose a visual score, using computed tomography to quantify emphysema in 61 subjects. 51 had chronic airflow obstruction (BPCO) and were divided into 31 chronic bronchitics (BC) and 20 emphysematous subjects (EP). 10 volunteers who were free of any respiratory pathology were chosen as controls. A visual score for the computed tomography was established for the subjects as a whole. Double reading of the data enabled the reproducibility of the method to be checked in 10 subjects (r = 0.98, p < 0.001). No emphysema was found in the 10 controls, the computed tomography score was appreciably more elevated in the EP subjects than in the BC group at 1.3 and 0.44 respectively (p < 0.001). In the BC, the computed tomographic score was not correlated with the PaO2 (r = 0.54, p < 0.001) and the FEV1 (VEMS) (r = < 0.44, p < 0.05). On the other hand, in the PE group, the score was correlated with the FEV1 (r = 0.52, p < 0.05) and the residual volume (r = 0.06, p < 0.05) and the total lung capacity (r = 0.63, p < 0.05) and the TLCO (r = 0.56, p < 0.05) and the TLCO/VA (r = 0.59, p < 0.05). The adoption of a visual computed tomographic score enabled the authors to find the correlations between pulmonary emphysema and the most specific tests of respiratory function.

Adult↗
PubMed1991

Case report: hydatid cyst of the aorta.

We report a rare case of hydatid cyst presenting as a 13 cm cyst in the wall of the lower mediastinal portion of the thoracic aorta associated with splenic and peritoneal cysts. The diagnostic problems are discussed.

Adult↗
PubMed1991

[Fistulas and ureteral strictures after kidney transplantation. Diagnosis and treatment].

We report our experience of 4 urine fistulas and 4 ureteral strictures after renal transplantation. Percutaneous nephrostomy was performed on all patients. The diagnosis was established by antegrade pyelography. Nephrectomy was performed on 2 patients because of failure of drainage and formation of an infected urine collection due to an extended ureteral necrosis. Abstention was elected in one case as renal function did not improve due to associated chronic rejection. In 5 cases, renal function quickly improved with drainage: 2 were operated on immediately, and one after failure of endo-urological treatment of a urine fistula. Antegrade dilatation has been used successfully in one stenosis. In the last case, a double pigtail stent allowed a urine fistula to close. Percutaneous nephrostomy seems to be best method of drainage when ureteral obstruction or fistula is suspected in renal transplant patients, and permits diagnosis by antegrade pyelography. Percutaneous management may be a satisfactory way of treatment for limited stenosis or fistulas.

Humans↗
PubMed1991

[Spontaneous subcapsular hematoma of the kidney].

A case of spontaneous subcapsular hematoma of the kidney is reported. CT scan findings and etiologies are examined in the light of previously published data. An etiology-specific therapeutic strategy for subcapsular hematoma of the kidney is proposed.

Diagnosis, Differential↗
PubMed1990

[Tuberculosis of the posterior vertebral arch. Apropos of 2 cases].

Spinal tuberculosis involving vertebral arc occurred in two patients. The first case had a single lesion presenting as a pseudo-tumoral feature. The second one had plurifocal tuberculosis peripheral and spinal one. The needle biopsy permitted the diagnosis in the two cases. Computed tomography showed the vertebral arch lesions with details and contiguous corporeal involvement. Clinical and radiological improvement was obtained after medical treatment.

Adolescent↗
PubMed1989

[Hepatic puncture-biopsy with embolization of the tract].

Recently reported by Shuang, percutaneous liver biopsy with embolisation of the tract (PLBET), involves the use of a coaxial needle system permitting embolisation of the tract while avoiding the haemorrhage complications of conventional biopsy. We conceived a system similar to shuang's 14G, 16G. We report the description of this system and the results obtained on 50 patients. Thanks to it simplicity we believe that PLBET should definitely replace definitely the transjugular liver biopsy (TLB).

Biopsy, Needle↗