Histological and chemical damage induced by microcystin-LR and microcystin-RR on land snail Helix aspersa tissues after acute exposure

Microcystins (MCs) are the most common cyanotoxins with more than 200 variants. Among these cyanotoxins, microcystin-LR (MC-LR) and microcystin-RR (MC-RR) are the most studied congeners due to their high toxicity and frequent occurrence in surface waters. MC-LR has been detected in more than 75% of natural cyanobacteria bloom, along with other toxic and less toxic congeners. Accumulation of several microcystins variants (MC-LR and MC-RR) has been confirmed in aquatic snails exposed naturally or in the laboratory to toxic blooms. Thus, this paper aims to compare the biochemical and histological impact of both toxic variants (microcystin-LR and microcystin-RR) and their mixed form on a bioindicator, the land snail Helix aspersa. During experiments, snails were gavaged with a single acute dose (0.5 μg/g) of purified MC-LR, MC-RR, or mixed MC-LR + MC-RR (0.25 + 0.25 μg/g). After 96 h of exposure, effects on the hepatopancreas, kidney, intestine and lungs were assessed by histological observations and analysis of oxidative stress biomarkers. The results show that a small dose of MCs variants can increase the non-enzymatic antioxidant glutathione (GSH), inhibit glutathione-s-transferase (GST) level and trigger a defense system by activating glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD). Microcystin-RR causes serious anomalies in the hepatopancreas and kidney than Microcystin-LR. The organ most affected is the kidney. The damage caused by MC-LR + MC-RR is greater than that caused by single variants.

Les polyphénols de l’extrait n-butanol de Crataegus oxyacantha : évaluation de leur pouvoir antioxydant et protecteur vis-à-vis de la toxicité de la doxorubicine

La doxorubicine (DOX) est un médicament utilisé en chimiothérapie anticancéreuse, son utilisation clinique est limitée en raison de plusieurs effets secondaires qui lui ont été attribués, comme la cardiotoxicité, la néphrotoxicité et l’hépatotoxicité. Dans la présente étude, nous avons étudié l’efficacité protectrice de l’extrait n-butanol d’une plante médicinale de la famille des Rosacées (Crataegus oxyacantha) contre la toxicité cardiaque, rénale et hépatique induite par la DOX chez des rats Wistar femelles en utilisant des paramètres biochimiques. Les rats ont été soumis à un traitement oral pré- et postphylactique concomitant par l’extrait n-butanol (100 mg/kg) contre la toxicité induite par injection intrapéritonéale unique de la DOX (150 mg/kg). La néphrotoxicité et l’hépatotoxicité ont été évaluées en mesurant les taux sériques de la créatinine, de l’urée, de l’aspartateaminotransférase (ASAT), de l’alanine-aminotransférase (ALAT) et du lactate-déshydrogénase (LDH). Le profil lipidique a également été mesuré. Le traitement par l’extrait n-butanol a considérablement diminué les taux des marqueurs sériques de la toxicité provoquée par la DOX. Les résultats biochimiques qui ont montré que la DOX a causé des dommages importants au niveau des tissus étudiés ont été inversés par l’extrait n-butanol. Les résultats suggèrent que l’extrait n-butanol atténue les lésions rénales, cardiaques et hépatiques induites par la DOX. Les tests antioxydants in vitro (piégeage du radical 2,2-diphényl-1-picrylhydrazyl et inhibition de la peroxydation lipidique) de l’extrait n-butanol ont révélé qu’il présente un pouvoir antioxydant très important ; ces activités sont fortement corrélées avec les teneurs en flavonoïdes et en phénols totaux.

Development and Initial Biogeochemical Applications of Compound-Specific Sulfur Isotope Analysis

Compound-specific isotope analysis (CSIA) has been extended to the 32S and 34S stable isotopes of sulfur (δ34S) through the combination of gas chromatography (GC) and multi-collector inductively coupled mass spectrometry (ICPMS). The molecular level resolution of sulfur-CSIA is greatly expanding the biogeochemical applications ofexisting sulfur isotope methods, particularly with respect to organic sulfur compounds. Sulfur participates in a variety of important biogeochemical and redox processes, with distinctive isotopic fractionations accompanying many of these. For example, hydrogen sulfideproduced duringmicrobial sulfate reduction can be strongly depleted in 34S (up to 66‰ in δ34S) compared to the source sulfate. An improved understanding of sulfur biogeochemistry at the molecular level will assist in the interpretation of studies of sulfur cycling associated with the modern and paleo-environments. A comparison of δ34S values between organic and inorganic sulfurspecies mayhelp to illuminate the complex role of sulfur in sedimentary organic diagenesis and the pathways of organic sulfurformation. The δ34S values of individual organic sulfur compounds from natural settings can be currently measured by GC-ICPMS with impressive accuracy, precision (<0.5‰) and sensitivity (≥20 pmol S) over a broad range of analyte volatility. The new sulfur-CSIA capability has already been used to study pathways of early diagenetic organic sulfurisation, volatile sulfur emission from the oceans, oil correlations, thermochemical sulfate reduction of petroleum hydrocarbons, and the relationship between OSCs and mineralising sulfides of large metal deposits.

[Factors influencing the development of chondrolysis in children treated for slipped capital femoral epiphysis]

INTRODUCTION

Chondrolysis is an infrequent but serious complication of the treatment of slipped capital femoral epiphysis. The objective of this study was to identify factors influencing the development of chondrolysis.

PATIENTS AND METHODS

The medical records of the patients operated on between 1989 and 2009 at the Rabat Children's Hospital for treatment of slipped capital femoral epiphysis were retrospectively evaluated. The minimum follow-up was 24 months. The risk of development of chondrolysis was correlated with various parameters. Statistical analysis was performed using a logistic regression model (binary outcome).

RESULTS

A total of 140 patients were included in this study. The average age was 13 years and 4 months. The incidence of chondrolysis was 11.4% (16 patients). Chondrolysis was significantly associated with obesity (25%, P<0.001) and with a delay in the diagnosis of slipped capital femoral epiphysis exceeding 60 days (75%, P=0.01) DISCUSSION: In this series, intra-articular pin penetration is not a risk factor for chondrolysis. The association of obesity and a diagnosis delay beyond 60 days increases the risk of occurrence of chondrolysis in children operated on for slipped capital femoral epiphysis. Chondrolysis can be prevented mainly through early diagnosis of slipped capital femoral epiphysis.

Membrane-bound oxygen reductases of the anaerobic sulfate-reducing Desulfovibrio vulgaris Hildenborough: roles in oxygen defence and electron link with periplasmic hydrogen oxidation

Cytoplasmic membranes of the strictly anaerobic sulfate-reducing bacterium Desulfovibrio vulgaris Hildenborough contain two terminal oxygen reductases, a bd quinol oxidase and a cc(b/o)o3 cytochrome oxidase (Cox). Viability assays pointed out that single Δbd, Δcox and double ΔbdΔcox deletion mutant strains were more sensitive to oxygen exposure than the WT strain, showing the involvement of these oxygen reductases in the detoxification of oxygen. The Δcox strain was slightly more sensitive than the Δbd strain, pointing to the importance of the cc(b/o)o3 cytochrome oxidase in oxygen protection. Decreased O2 reduction rates were measured in mutant cells and membranes using lactate, NADH, ubiquinol and menadiol as substrates. The affinity for oxygen measured with the bd quinol oxidase (Km, 300 nM) was higher than that of the cc(b/o)o3 cytochrome oxidase (Km, 620 nM). The total membrane activity of the bd quinol oxidase was higher than that of the cytochrome oxidase activity in line with the higher expression of the bd oxidase genes. In addition, analysis of the ΔbdΔcox mutant strain indicated the presence of at least one O2-scavenging membrane-bound system able to reduce O2 with menaquinol as electron donor with an O2 affinity that was two orders of magnitude lower than that of the bd quinol oxidase. The lower O2 reductase activity in mutant cells with hydrogen as electron donor and the use of specific inhibitors indicated an electron transfer link between periplasmic H2 oxidation and membrane-bound oxygen reduction via the menaquinol pool. This linkage is crucial in defence of the strictly anaerobic bacterium Desulfovibrio against oxygen stress.

[Glomus tumor of the finger pulp: an unusual pediatric case]

Glomus tumor is a rare benign tumor. Diagnosis is often delayed because of the absence of specific symptoms and confirmation can only be made by histological study. Treatment is always surgical. We report a clinical case of glomus tumor of the thumb pulp in a 6-year-old girl, and we discuss clinical, radiological and histological aspects of this tumor.

Displaced femoral neck fractures in children: are complications predictable?

INTRODUCTION

Serious complications can occur in the management of displaced femoral neck fractures in children. Are there ways to anticipate this risk and better define eventual contributing factors?

PATIENTS AND METHODS

Twenty-one children (14 boys and 7 girls) were treated between 1999 and 2006 for displaced femoral neck fractures. Nine type II, 10 type III and two type IV fractures were observed according to the Delbet's classification. Anatomical open reduction was performed in 13 patients and closed reduction in eight patients. At a mean follow-up of 26.4 months, the outcome was assessed according to the Ratliff criteria. Postoperative complications were analysed according to the age, fracture type, time-to-surgery and open or closed reduction.

RESULTS

The mean age was 12.1 years. The final outcome was defined as good in 14 patients(66.66%), fair in one patient (4.76%) and poor in six patients (28.58%). Complications occurred in seven patients (33.33%), avascular necrosis (AVN) of the femoral head being the most frequent one (28.58%). In all cases, necrosis was observed in children older than 12 years (p < 0.05) and when time-to-surgery exceeded 48 h (p < 0.05). Necrosis occurred in 44.44% of type II fractures and in 20% of type III fractures (p > 0.05). Only one materialised after closed reduction (p < 0.05).

DISCUSSION

Various factors may contribute to the development of complications in children with femoral neck fractures. Our study supports the hypothesis that older age, late surgery and open reduction are definite predictors of avascular necrosis occurrence.

LEVEL OF EVIDENCE

Retrospective study, level IV.

[Risk factors of osteonecrosis of the femoral head following slipped capital femoral epiphysis]

Osteonecrosis is a serious complication of the treatment of slipped capital femoral epiphysis. The purpose of this study was to identify factors predisposing to the development of this complication. We reviewed retrospectively 127 patients (150 hips) treated for slipped capital femoral epiphysis in our institution between 1980 and 2004. Clinical and radiological data were analyzed before and after treatment, and at consecutive follow-up examination. Osteonecrosis was defined in the basis of radiological criteria. The risk of development of osteonecrosis was correlated with multiple clinical and radiographic parameters.

RESULTS

12 hips in 11 patients (8%) had development of osteonecrosis. Ten of them had an unstable slip. From 130 stable hips, regardless of grade, two had development of osteonecrosis. In patients who had presented with an unstable hip, the risk of osteonecrosis increased with the grade of the slip. Osteonecrosis was more likely to develop in hips that had been treated with multiple screws than in those who had been treated with a single screw. In conclusion, partial or complete reduction of an unstable slipped capital femoral epiphysis increases the risk of development of osteonecrosis. Pinning in situ without reduction with a single screw is the method of choice of the treatment of a slipped capital femoral epiphysis.

[Supra and intercondylar elbow fractures in children]

Supra- and intercondylar elbow fractures are rare in children. The treatment of these fractures is controversial. The purpose of this report is to discuss diagnosis and treatment of this unusual injury. Our study looked at nine patients between six and 15 years old (average age: 11.5). In four patients, the fracture was T-condylar and in five patients, the fracture was epiphyseal-diaphyseal. Communition was noted in five cases. All fractures are secondary to high-energy trauma. All patients were treated by open reduction and internal fixation. Three patients had associated nervous lesions. Patients were reviewed at an average of 30 months follow-up and the results evaluated according to the criteria of Flynn. The results were good or excellent in six patients, fair in two patients and poor in one. Cubitus varus and limitation of elbow motion were the main complication. Supra- and intercondylar elbow fractures should be differentiated from the more common supracondylar humerus fractures. We recommended open reduction with internal fixation. Complications are due to the severity of the initial trauma and sometimes to defective treatment especially in the case of complex fracture.

Pronator teres transfer to correct pronation deformity of the forearm after an obstetrical brachial plexus injury

A pronation deformity of the forearm following an obstetric brachial plexus injury causes functional and cosmetic disability. We evaluated the results of pronator teres transfer to correct their deformity in 14 children treated over a period of four years. The mean age at surgery was 7.6 years (5 to 15). The indication for surgery in each case was impairment of active supination in a forearm that could be passively supinated provided that there was no medial contracture of the shoulder and normal function of the hand. The median follow-up was 20.4 months (8 to 42). No patient was lost to follow-up. Qualitative results were also assessed. The median active supination improved from 5 degrees (0 degrees to 10 degrees ) to 75 degrees (70 degrees to 80 degrees ) with no loss of pronation. A passively correctible pronation contracture can be corrected safely and effectively by the transfer of pronator teres.

False aneurysm of the radial artery: Unusual complication of both-bone forearm fracture in children: A case report

False aneurysm or pseudo aneurysm of an artery in close proximity to fractured bone is a well-recognized entity, and fewer various cases, involving different sites have been reported in the literature. We report new case of a Moroccan's patient who had 10-year-old boy presented with a right non displaced both-bone forearm fracture; the patient was placed in a long arm splint. After, six weeks, the cast was removed. And a pulsatile mass on the volar-radial aspect of the forearm was decouvred. The mass was non-tender and the patient had radial and ulnar pulse. An Ultrasound and brachial angiography showed a false aneurysm of distal radial and the radial artery was ligated.In conclusion, pseudoaneurysm of the radial artery can be associated with any bone fracture despite non displacing fractures related to the elasticity of the bone in this age and orthopedic surgeons should be aware of this potential complication.

Marked genetic differences in the regulation of blood glucose under immune and restraint stress in mice reveals a wide range of corticosensitivity

Male and female mice from different control strains (C57BL/6, DBA/2, BALB/c) and the nonobese diabetic (NOD) strain, a spontaneous model of type 1 diabetes, were subjected to various stressors (restraint, lipopolysaccharide or interleukin-1 injection). Significant differences were measured among strains in blood glucose, insulin and corticosterone levels and, for restraint, IL-6. Addition of dexamethasone, a glucocorticoid receptor agonist, to inhibit the expression of several proteins by LPS-stimulated bone marrow-derived macrophages in vitro showed a gradient among control strains: C57BL/6>DBA/2>BALB/c corroborating the pattern of corticosensitivity suggested by their stress-induced glucose responses at the systemic level.

[Muscular tuberculosis: an unusual focus of Koch bacillus]

We report an exceptional case of tuberculosis in an 8-year-old girl. The focus of infection was situated in the anterior muscle compartment of the left thigh. Diagnosis was established on the basis of histological findings. A 12-month antituberculosis regimen was given. Outcome was good with no general or functional sequelae. Based on this case and data reported in the literature, we discuss the routes of dissemination of the Koch bacillus explaining this unusual sporadic localization.

[Role of laparoscopy in intra-abdominal testes in children. 35 case reports]

The impalpable testicles account for approximately 10 to 20% of the total of the not descended testicles. The importance of laparoscopy is increasingly significant, because apart from its diagnostic role recently a therapeutic interest was added. Thirty-five nonpalpable testicles took advantage of laparoscopic exploration at the pediatric's emergency surgery ward at the children's hospital of Rabat within the last 2 years. In 9 cases, total testicular agenesis was found. In 6 cases the testicles were situated very high in the abdomen, so that a first time laparoscopy was performed where the testicles were lowered. In 10 cases, one laparoscopic intervention for lowering the testicles was sufficient. In 10 cases, laparoscopic surgery showed that the vas deferens and the spermatic vessels reunified in the inguinal; so that, Inguinal exploration was necessary. The time of hospitalisation was 24 h with no complications noticed. We present this work to sensitise the surgeons on the new therapeutic approach to optimise the taking care of cryptorchid boys.

[Medico-economic study of percutaneous and surgical closure of ostium secundum type interatrial communications]

The aim of this study was the medico-economic evaluation of the closure of ostium secundum type interatrial communications in 32 patients, treated by cardiac catheterisation (group A: n = 17) or by surgery (group B: n = 15). The success rate was 100% with the 2 techniques. With national cost scale data we evaluated the overall cost of the 2 treatments using the information system medical program, starting from homogenous groups of patients: 150 catheterisation, 169 and 170 surgery. As the value for the homogenous group of 150 patients was much lower than the price of the material used for catheterisation, an adjusted group of 150 patients including the price of this material was created. An evaluation in terms of an artificial index of activity was also performed. The average duration of hospital stay for group A was reduced by 6.1 days compared to group B (p < 0.001). The overall cost was lower in group A than in group B (p < 0.001), using the real and "adjusted" homogenous group of 150 patients, with a respective reduction of 7,582 Euros and 3,731 Euros. Surgery and catheterisation scored 8,167 points (17,756 Euros) and 2,726 points (5,926 Euros) per patient respectively on the artificial activity index. In conclusion, catheterisation reduced the duration of hospital stay and brought an economic benefit for the Assurance Maladie compared to surgery. However, surgery is more profitable for the hospital than catheterisation because of the high cost of the prosthesis, which is not taken into account with a homogenous group of non-specific patients. This could hamper the development of this innovative technique in a hospital subjected to overall budgetary constraints.