[Sugar tumor]. / Tumeur sucre.

BACKGROUND: Clear cell tumor of the lung is a rare and very unusual benign pulmonary tumor. This tumor is called sugar tumor because of the abundance of glycogen on its cells. AIM: To report a case of sugar tumor and discuss clinical, evolutive features and diagnosis difficulties of this tumor. CASE REPORT: A case of 75 years old woman presenting as a round pulmonary opacity. Computed tomography (CT) scans showed in the left lower lobe a solitary pulmonary solid tumor with central calcifications. The patient underwent tumor resection. Pathologic examination, including immunohistochemical studies, revealed a benign clear cell tumor, so-called "sugar tumor". CONCLUSION: It's the second case reported in Tunisia. This very rare tumor of the lung is characterized by some immunohistological features. Its evolution is favourable after surgery.

[Sarcoidosis in Tunisia: epidemiologic and clinical study]. / Sarcoïdose en Tunise: partcularités épidémiologiques et cliniques.

BACKGROUND: The epidemiologic study of sarcoidosis is problematic and differing incidences across the world are reported. In Tunisia, the incidence of this affection is yet unknown. This is at least attributable to the lack of large series and the overshadowing presence of tuberculosis. AIM: To determine presenting signs, symptoms and investigations particularities. METHODS: We report a retrospective series patients with sarcoidosis followed up in the Rabta university hospital between 1991 and 2005 and try to determine presenting signs, symptoms and investigations particularities. RESULTS: 131 patients (79 women and 52 men) with a median age of 47 ± 14 years were reviewed. They were symptomatic in 95 % of cases. Cutaneous symptoms were present at onset in 56.8 %, respiratory symptoms in 48.6 % and general symptoms in 41.6 %. Thoracic presentation was observed in 81.3%. Chest X-ray changes and tomodensitometry showed that type II and III were predominant. Lung function was disturbed in 58.5% of the cases. Extrathoracic involvement, observed in 89.3 % of the cases, was largely dominated by cutaneous lesions. Histopathological lesions provided diagnosis in 66.6%. CONCLUSION: The relative high frequency of dermatological lesions suggests genetic or even environmental predisposition to develop sarcoidosis such as sunlight exposition.

Transitory, spontaneously recovering, peripheral facial nerve palsy after vionorelbine administration.

BACKGROUND: Vinorelbine is a semi-synthetic vinca alkaloid that has demonstrated a broad spectrum of activity. It is widely used in non small cell lung cancer. CASE REPORT: We report the case of a 50 year old man, having stage IV lung carcinoma with a unique cerebral metastasis in the right hemisphere. Focal cerebral radiotherapy was first administrated followed by intravenous chemotherapy associating vinorelbine to cisplatin. He has developed multiple subsequent and transitory episodes of monolateral peripheral facial nerve palsy in the left side during vinorelbine administration. The palsy has completely and spontaneously resolved at a short interval, around twenty minutes, after the end of the drug infusion. Obvious cerebral tumor progression was excluded by means of CT scan; the drug was thereby administrated as scheduled until the end of the treatment. CONCLUSION: We describe an unusual side effect, until now reported in only two cases, having brain-stem gliomas, among English and French literature, dealing with vinorelbine as adjuvant treatment. We discuss possible neurological and oncological implications.

[Pulmonary tuberculosis in child]. / Les particularités de la tuberculose pulmonaire chez l'enfant.

Pulmonary tuberculosis is a major public health problem in the world and particularly in Tunisia. Child is not saved by this illness. The pulmonary tuberculosis present epidemiological and diagnosis specificity in child, especially characterized by difficulty diagnosis at this age. It is also characterised by therapeutic difficulties.

Cellular senescence induces replication stress with almost no affect on DNA replication timing.

Organismal aging entails a gradual decline of normal physiological functions and a major contributor to this decline is withdrawal of the cell cycle, known as senescence. Senescence can result from telomere diminution leading to a finite number of population doublings, known as replicative senescence (RS), or from oncogene overexpression, as a protective mechanism against cancer. Senescence is associated with large-scale chromatin re-organization and changes in gene expression. Replication stress is a complex phenomenon, defined as the slowing or stalling of replication fork progression and/or DNA synthesis, which has serious implications for genome stability, and consequently in human diseases. Aberrant replication fork structures activate the replication stress response leading to the activation of dormant origins, which is thought to be a safeguard mechanism to complete DNA replication on time. However, the relationship between replicative stress and the changes in the spatiotemporal program of DNA replication in senescence progression remains unclear. Here, we studied the DNA replication program during senescence progression in proliferative and pre-senescent cells from donors of various ages by single DNA fiber combing of replicated DNA, origin mapping by sequencing short nascent strands and genome-wide profiling of replication timing (TRT). We demonstrate that, progression into RS leads to reduced replication fork rates and activation of dormant origins, which are the hallmarks of replication stress. However, with the exception of a delay in RT of the CREB5 gene in all pre-senescent cells, RT was globally unaffected by replication stress during entry into either oncogene-induced or RS. Consequently, we conclude that RT alterations associated with physiological and accelerated aging, do not result from senescence progression. Our results clarify the interplay between senescence, aging and replication programs and demonstrate that RT is largely resistant to replication stress.

[Isoniazid acetylation in a group of Tunisian patients. Report of 620 patients]. / Profil acétyleur d'une population de tuberculeux Tunisiens. A propos de 620 cas.

Isoniazid is a first line antituberculosis drug metabolized mainly in the liver by the Nacetyltransferase. There are differences between individuals in acetylation metabolism. Subjects are thereby characterized as being rapid or slow acetylators. The purpose is to study the distribution pattern of acetylation in patients with tuberculosis followed up at the teaching Hospital of La Rabta. The determination of acetylator phenotype was carried out on 620 tuberculosis patients during a period of 12 years. There were 483 men and 137 women with a median age of 40.3 years. The test was investigated before drug regimen administration at the dose of 5 mg/kg. A blood sample was taken three hours after the first administration. The determination of acetylation profile was worked out by Vivien hypothesis. In our population 391 were low and 229 were fast acetylators. The median dose recommended within the test was 3.04 mg/kg/day. 56% of our patients were initially receiving high dose of isoniazid. An increase in serum transaminase was initially observed in 60 patients among whom 47 slow acetylators. After dose adaptation, 53 patients had improved their biological abnormalities. The majority of Tunisian population seem to belong to slow acetylators modal. The frequency of hepatotoxicity suggests reducing the recommended dose of isoniazid from 5 to 3 mg/kg/day.