Canavan disease or N-acetyl aspartic aciduria: a case report]

Canavan disease or N-acetyl aspartic aciduria, is an autosomal recessive leukodystrophy characterized by spongy degeneration of brain. The disease is an inborn error of metabolism caused by aspartoacylase deficiency resulting from accumulation of N-acetyl aspartic acid in the brain. The authors report a case in a 10-month-old boy who presented with developmental delay and megalencephaly noticeable after 4 months of age. Magnetic resonance imaging of the brain showed diffuse white matter degeneration. The diagnosis of Canavan disease was confirmed by nuclear magnetic resonance spectroscopy and gas chromatography-mass spectrometry.     

Identification of a novel frameshift mutation in the DFNB31/WHRN gene in a Tunisian consanguineous family with hereditary non-syndromic recessive hearing loss

Approximately 80% of hereditary hearing loss is non-syndromic. Non-syndromic deafness is the most genetically heterogeneous trait. The most common and severe form of hereditary hearing impairment is autosomal recessive non-syndromic hearing loss (ARNSHL), accounting for approximately 80% of cases of genetic deafness. To date, 22 genes implicated in ARNSHL have been identified. Recently a gene, DFNB31/WHRN, which encodes a putative PDZ scaffold protein called whirlin, was found to be responsible for the ARNSHL DFNB31. We found evidence for linkage to the DFNB31locus in a consanguineous Tunisian family segregating congenital profound ARNSHL. Mutation screening of DFNB31/WHRNrevealed four nonpathogenic sequence variants and a novel frameshift mutation [c.2423delG] + [c.2423delG] that changed the reading frame and induced a novel stop codon at amino acid 818 ([p.Gly808AspfsX11] + [p.Gly808AspfsX11]). To determine the contribution of the DFNB31locus in the childhood deafness, we performed linkage analysis in 62 unrelated informative families affected with ARNSHL. No linkage was found to this locus. From this study, we concluded that DFNB31/WHRN is most likely to be a rare cause of ARNSHL in the Tunisian population.     

Doppler echocardiographic study of left ventricular diastolic function in hemodialysis patients

OBJECTIVES: The purpose of this study is to examine the diastolic dysfunction particularities in hemodialysis patients and to identify the parameters having the most discriminating power of diastolic dysfunction. METHODS: Conventional Doppler echocardiography study implies left ventricular diastolic function from Doppler transmitral flow (E/A), color M-mode flow propagation velocity (Vp) and combined indexes: ratio of peak E-wave velocity to Vp (ENp) and difference in duration of pulmonary venous and mitral flow at atrial contraction (Ap-Am). RESULTS: Left ventricular diastolic dysfunction is found in 86% of the 100 hemodialysis patients: abnormal relaxation pattern 52%, pseudo-normal pattern 21%, restrictive pattern 13%. Left ventricular hypertrophy is independent of blood pressure (eta2=3.386; p>0.06). Diastolic function pattern has no relation with duration of dialysis treatment (F=2.637, p>0.05) or left ventricular mass (F=4.298, p>0.06). We noted correlations with age for all parameters of transmitral Doppler flow (p<0.01), Vp and systolic fraction except combined indexes (p>0.05). Doppler parameters of which discriminating power is significant (p<0.001) are in deceasing order: isovolumic relaxation time, E/A, Vp, early filling deceleration time, Ap-Am, E/VP and systolic fraction. The parameter Vp discriminates normal filling from abnormal or pseudo-normal patterns. However it doesn't allow any discrimination between abnormal and pseudo-normal patterns or abnormal and restrictive patterns. Discriminating analysis classify correctly 100% of pseudo normal pattern patients with 2 variables (isovolumic relaxation time and Vp or VP with E/Vp). Factor analysis suggests that Vp characterizes normal pattern and E/A ratio and Ap-Am characterize restrictive pattern. CONCLUSION: Parameters of diastolic function discriminating value is different from one stage to another. VP characterizes normal pattern, combined indexes restrictive pattern. Vp and isovolumic relaxation time discriminates normal from pseudo-normal pattern.     

Prognosis of periprosthetic regurgitation after mitral valve replacement using the Saint Jude prosthesis

Periprosthetic regurgitation (PPR) is a common complication of mitral valve replacement (MVR). The management of moderate and minor PPR remains controversial. The goal of this prospective study was to determine the incidence, predictors and outcome of PPR discovered using omniplan transoesophageal echocardiography (TEE) performed at the early postoperative period (14.7 days) of MVR with SJM prosthesis. Our study enrolled 56 patients, the mean age was 44.5 +/- 11.9 years. The incidence of PPR was 59% (33 patients). TEE showed one jet in nine patients (27%), two jets in 23 patients (70%) and three jets in one patient (3%). PPR is minor in 24 patients (63%) and moderate in nine patients (27%). No patient developed hemolytic anemia or congestive heart failure. In univariate analysis, diameter of prostheses > 27 mm, number of suture knots < 17 and diameter of prostheses/number of knot ratio > 1.7 independently predicted the presence of PPR. In multivariate analysis only a rapport diameter of protheses/number of suture knots > 1.7 mm is predictif of PPR (odd ratio = 9, P = 0.036). Ninety percent of PPR remained present at six weeks and only 29% were present after 12.5 months. CONCLUSION: Mild and minor PPR were frequent during the early postoperative period after MVR. The clinical significance and natural history is benign and they do not require any specific treatment.     

Prognostic utility of pre-transplantation [18F] fluorodeoxyglucose positron emission tomography/computed tomography in patients with diffuse large B-cell lymphoma who underwent rituximab,dexamethasone, high-dose cytarabine,carboplatin salvage chemotherapy

We analysed the outcomes of 62 patients with refractory/relapsed diffuse large B-cell lymphoma (rrDLBCL) who had pre-transplantation fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) after R-DHAC (rituximab, dexamethasone, high-dose cytarabine, carboplatin) salvage chemotherapy, and were evaluated using Deauville criteria and total lesion glycolysis (TLG). A positive pre-transplantation PET/CT with Deauville score of 5 was associated with shorter progression-free survival (PFS) (P = 0·01), while a Deauville score of 4 was not predictive of outcome. Only pre-transplant TLG was significantly associated with both PFS (P = 0·005) and overall survival (P = 0·03). TLG deserves to be further investigated in prospective studies.     

Synovite villonodulaire pigmentée de la métatarsophalangienne de l’hallux

Villonodular pigmented synovitis is a benign, idiopathic proliferative and locally aggressive disorder of the synovium that have been reported to manifest within joints, tendon sheaths, and bursae. Usually, only one joint is affected, especially the knee. The localization in the foot is rare. The authors present a case of a villonodular synovitis of the metatarsophalangeal joint of the hallux. A review of the literature highlights this case.     

Fish oil increases mitochondrial phospholipid unsaturation,upregulating reactive oxygen species and apoptosis in rat colonocytes

We have shown that a combination of fish oil (high in n-3 fatty acids) with the butyrate-producing fiber pectin, upregulates apoptosis in colon cells exposed to the carcinogen azoxymethane, protecting against colon tumor development. We now hypothesize that n-3 fatty acids prime the colonocytes such that butyrate can initiate apoptosis. To test this, 30 Sprague-Dawley rats were provided with diets differing in the fatty acid composition (corn oil, fish oil or a purified fatty acid ethyl ester diet). Intact colon crypts were exposed ex vivo to butyrate, and analyzed for reactive oxygen species (ROS), mitochondrial membrane potential (MMP), translocation of cytochrome C to the cytosol, and caspase-3 activity (early events in apoptosis). The fatty acid composition of the three major mitochondrial phospholipids was also determined, and an unsaturation index calculated. The unsaturation index in cardiolipin was correlated with ROS levels (R = 0.99; P = 0.02). When colon crypts from fish oil and FAEE-fed rats were exposed to butyrate, MMP decreased (P = 0.041); and translocation of cytochrome C to the cytosol (P = 0.037) and caspase-3 activation increased (P = 0.032). The data suggest that fish oil may prime the colonocytes for butyrate-induced apoptosis by enhancing the unsaturation of mitochondrial phospholipids, especially cardiolipin, resulting in an increase in ROS and initiating apoptotic cascade.     

Tuberculous mesenteric lymphadenitis: a case report

The authors report a case of mesenteric tuberculous lymphadenitis which mimic a pancreatic cystadenoma. They emphasize ultrasound and CT scan features which lead to the recognition of tuberculosis and permit a percutaneous fine needle biopsy. Laparotomy seems the most reliable method for a positive diagnosis. The place of different imaging methods is discussed.