Bariatric surgery related proximal myopathy: A partially reversible complication.

Deficiency neuropathies and rhabdomyolysis have previously been reported after bariatric surgery (BS) but never myopathies. We report cases of five patients with morbid obesity who developed within 2 to 4 months of a BS, proximal myopathy following significant and rapid weight loss worsened by postoperative gastrointestinal complications. Muscle weakness concerned lower limbs in particular in quadriceps and less frequently in upper limbs and diaphragm, sometimes mimicked a Guillain-Barré syndrome. Muscle biopsy performed in 1 patient, revealed selective atrophy of type 2 fibers. Weakness slowly decreased with refeeding with vitamins supplementation. We enlarge here the clinical pattern of post-BS complications.

Somatosensory evoked potentials in the assessment of peripheral neuropathies: Commented results of a survey among French-speaking practitioners and recommendations for practice.

BACKGROUND: Somatosensory evoked potentials (SSEPs) are increasingly performed for the assessment of peripheral neuropathies, but no practical guidelines have yet been established in this specific application. STUDY AIM: To determine the relevant indication criteria and optimal technical parameters for SSEP recording in peripheral neuropathy investigation. METHODS: A survey was conducted among the French-speaking practitioners with experience of SSEP recording in the context of peripheral neuropathies. The results of the survey were analyzed and discussed to provide recommendations for practice. RESULTS: SSEPs appear to be a second-line test when electroneuromyographic investigation is not sufficiently conclusive, providing complementary and valuable information on central and proximal peripheral conduction in the somatosensory pathways. CONCLUSIONS: Guidelines for a standardized recording protocol, including the various parameters to be measured, are proposed. CLINICAL RELEVANCE: We hope that these proposals will help to recognize the value of this technique in peripheral neuropathy assessment in clinical practice.

Increased incidence of Campylobacter jejuni-associated Guillain-Barré syndromes in the Greater Paris area.

The role of Campylobacter jejuni as the triggering agent of Guillain-Barré syndrome (GBS) has not been reassessed since the end of the 1990s in France. We report that the number of C. jejuni-related GBS cases increased continuously between 1996 and 2007 in the Paris region (mean annual increment: 7%, P = 0·007).

[Results of a prospective standardized study of 30 patients with chronic neurological and cognitive disorders after tick bites]. / Enquête étiologique standardisée sur une cohorte de 30 patients atteints de troubles neurologiques et cognitifs chroniques après piqûre de tiques results of a prospective standardized study of 30 patients with chronic neurological and cognitive disorders after tick bites.

OBJECTIVE: Patients with chronic neurological disorders and cognitive impairment after tick bites are difficult to manage despite standard antibiotic therapy for Lyme disease. We wanted to correctly assess the disorders. METHODS: Thirty patients were hospitalized for a standardized evaluation of their disorders: clinical examination, biological and serological studies, cerebral MRI, CSF study, neurophysiological exams, and neuropsychological evaluation of cognitive functions. RESULTS: Clinical and biological results were non informative. We observed significant CSF abnormalities (64%), MRI Flair pictures (41%), neurophysiological exams (47%), and cognitive evaluation (100%). CONCLUSIONS: A large and standardized evaluation should be made for each patient to improve the management and probably the treatment of these complex chronic symptoms observed after tick bites.

A gene for an autosomal recessive lower motor neuron disease with childhood onset maps to 1p36.

OBJECTIVE: To describe the clinical features of a novel variant of autosomal recessive lower motor neuron disease (LMND) with childhood onset and to map the disease-causing gene. METHODS: The authors performed a clinical study in a large consanguineous African family. After linkage exclusion to SMN1 and SOD1 loci, they performed a genome-wide linkage analysis to map the underlying genetic defect. RESULTS: This novel variant of LMND with childhood onset and autosomal recessive mode of inheritance is characterized by a progressive symmetric and generalized involvement of the musculature. Four of the five affected patients had muscle weakness since age 3, strongly worsening during childhood and leading to generalized tetraplegia in adulthood. Genetic analyses using homozygosity mapping strategy assigned this progressive generalized LMND locus to an interval of 3.9 cM (or 1.5 megabases) on chromosome 1p36, between loci D1S508 and D1S2633 (Z(max) = 3.79 at theta = 0.00 at locus D1S253). This region encloses 27 candidate genes. CONCLUSION: Genetic mapping of a novel rare phenotype of lower motor neuron disease opens the way toward the identification of a new gene involved in motor neuron degeneration, located in the 1p36 chromosomal region.

Significance of phrenic nerve electrophysiological abnormalities in Guillain-Barré syndrome.

The authors investigated whether the amplitude and latency of diaphragm compound muscle action potential helped predict respiratory failure in Guillain-Barré syndrome. Both variables were significantly but weakly correlated with vital capacity (VC) and were similar in unventilated (n = 60) and ventilated (n = 10) patients. In ventilated patients, motor loss severity, progression, and VC reduction were significantly greater, and bulbar dysfunction was more common. Predicting respiratory failure must rely on clinical features and VC.

[Prevalence and characteristics of Guillain-Barré syndromes associated with Campylobacter jejuni and cytomegalovirus in greater Paris]. / Prévalence et caractéristiques des syndromes de Guillain-Barré associés à Campylobacter jejuni et au cytomégalovirus en région parisienne.

AIM OF THE STUDY: We aimed to study prevalence and features of Campylobacter jejuni and cytomegalovirus (CMV)-associated Guillain-Barré syndromes (GBS) in a French care unit. PATIENTS AND METHODS: We studied 264 patients with GBS admitted at Raymond Poincaré hospital (Garches) between 1996 and 2001. Clinical data were obtained prospectively. Sera were collected at patients entry and tested retrospectively for anti-C. jejuni, anti-CMV and antigangliosides GM1 et GM2 antibodies. RESULTS: GBS associated with a serological evidence for a recent C. jejuni infection were the more frequent (58/264, 22%); they affected predominantly men of mature years (mean age: 51.3 years; sex-ratio M/F: 1.76), mostly after a gastrointestinal illness (52%); they were often pure motor forms (57%), were severe (mechanical ventilation: 40%) and associated to an anti-GM1 IgG and/or IgM response (44%). GBS cases involving a primary CMV infection were less frequent (40/264, 15%), but were severe too (mechanical ventilation: 37.5%); they occurred preferentially in young women (mean age: 35.9 years; sex-ratio MF: 0.82), often after respiratory tract symptoms (28%) or an influenza-like syndrome (15%) and were frequently associated with sensory loss (73%) and with an anti-GM2 IgM response (47%). CONCLUSION: C. jejuni and CMV proved to be major triggering agents of GBS in France. They are associated with distinct presentations, which are both severe.

Electrophysiology to predict mechanical ventilation in Guillain-Barré syndrome.

To determine whether electrophysiological features predict endotracheal mechanical ventilation (ETMV) in Guillain-Barré syndrome (GBS). Non-ventilated GBS patients admitted to an ICU underwent standard electrophysiological testing. Endotracheal mechanical ventilation was decided by physicians who were unaware of electrophysiological results. Sixty consecutive patients underwent electrophysiological testing within 17 days of GBS onset; based on Hadden's criteria, 37 (62%) had primary demyelinating, 18 (30%) equivocal and five (8%) axonal disease. Time at electrophysiological testing and proportions of patients treated by plasma exchange and intravenous immunoglobulins were similar in the three groups, whereas primary demyelinating patients had worse results for disability grade and arm grade. The ETMV was required within 20 days of electrophysiological testing in 20 patients, 17 (46%) in the primary demyelinating group, three (17%) in equivocal group and none in the axonal group (P = 0.02). This prospective study suggests that electrophysiological demyelination may predict a need for ETMV in GBS.

MMP-9 correlates with electrophysiologic abnormalities in Guillain-Barré syndrome.

To investigate the role of MMP-9 in Guillain-Barré syndrome, the authors correlated electrophysiologic abnormalities and MMP-9 plasma levels in a series of 21 patients. MMP-9 plasma levels were higher in the demyelinating group than in the nondemyelinating group, and in patients with high CSF protein level. Increase of MMP-9 circulating levels correlated with the increase of F waves latencies, reduction of CMAP amplitude, and decrease of nerve conduction velocities. Circulating MMP-9 may contribute to the peripheral nerve dysfunction of demyelinating Guillain-Barré syndrome.

Kashin-Beck disease and drinking water in Central Tibet.

A cross-sectional survey was carried out in order to study the relationship between Kashin-Beck disease and drinking water. The average volume of the water containers was larger in families unaffected by the disease. Organic material was measured by ultraviolet (UV) spectroscopy. The UV absorbency was significantly lower in drinking water of unaffected families. Thus, the organic material in drinking water may play a role in the pathogenesis of Kashin-Beck disease.

Epidemiological support for a multifactorial aetiology of Kashin-Beck disease in Tibet.

We carried out a cross-sectional study in 12 rural villages in order to identify the risk factors for Kashin-Beck disease in Tibet. Children aged 5-15 years (n=575) were examined and their corresponding houses were visited. Samples were collected in order to study fungal contamination of stored grain and the organic matter content of drinking water. Multivariate analysis was performed using logistic regression and population attributable fractions were computed to estimate the impact of each factor. The following variables were independently associated with the disease: age, gender, low socio-economic status, indicators of a poorly diversified diet, iodine deficiency and small water container size (with higher organic matter levels in small containers). Selenium deficiency was severe in all study subjects. The degree of fungal contamination of barley grain was related to the highest percentage of cases (65%) in a sample of the study population. Higher urinary iodine levels were not associated with decreasing prevalence rates when Alternaria sp. was isolated. The data that we report supports the hypothesis that Kashin-Beck disease occurs as a consequence of oxidative damage to cartilage and bone cells when associated with decreased antioxidant defence. Another mechanism that may coexist is bone remodelling stimulated by thyroid hormones whose actions can be blocked by certain mycotoxins.

[Electrophysiologic study of 10 cases of Miller Fisher syndrome]. / Etude électrophysiologique de 10 cas de syndrome de Miller Fisher.

The association of ophthalmoplegia, ataxia and areflexia was described by Miller Fisher in 1956. It is postulated as a variant of the Guillain Barré syndrome. We report 10 Miller Fisher syndrome patients admitted in an intensive care unit between June 1990 and February 1999 who were selected according to clinical criteria of Ropper and Wijdicks. All patients had motor and sensory nerve conduction studies and electromyography, nine had visual and brainstem auditory evoked potentials and two had short latency somatosensory evoked potentials. Peripheral neuropathy was found in all patients. All had sensory nerve changes and some were severe. Motor nerve conduction abnormalities were observed in 7 only cases with moderate increase of F latency in 3 cases and compound muscle action potential reduction in 3 other cases. In the last case, motor conduction abnormalities was more severe, characterized by conduction velocity slowing in both distal and proximal sites and by temporal dispersion of action potentials. All brainstem auditory evoked studies were normal. In 4 patients, MRI studies were normal. These data support that brainstem is preserved in MFS. Only one patient had visual evoked potential abnormalities. Optic neuropathy is debated in Miller Fisher and in Guillain Barré syndrome. As a conclusion, in MFS peripheral neuropathy is always present with severe sensitive changes and moderate motor changes (This is different as compared to Guillain Barré syndrome according to electrophysiological data). We did not find involvement of brainstem in our patients with Miller Fisher syndrome.

Escherichia coli is able to produce heterologous tetraheme cytochrome c(3) when the ccm genes are co-expressed.

The production of Desulfovibrio vulgaris Hildenborough cytochrome c(3) (M(r) 13000), which is a tetraheme cytochrome, in Escherichia coli was examined. This cytochrome was successfully produced in an E. coli strain co-expressing the ccmABCDEFGH genes involved in the cytochrome c maturation process. The apocytochrome c(3) was matured in either anaerobic or aerobic conditions, but aerobic growth in the presence of delta-aminolevulinic acid was found to be best for cytochrome c(3) production. Site-directed mutagenesis was performed to investigate the effect of the presence of four amino acids in between the two cysteines of the heme binding sites 2 and 4 on the maturation of holocytochrome c(3) in E. coli.

The Desulfuromonas acetoxidans triheme cytochrome c7 produced in Desulfovibrio desulfuricans retains its metal reductase activity.

Multiheme cytochrome c proteins that belong to class III have been recently shown to exhibit a metal reductase activity, which could be of great environmental interest, especially in metal bioremediation. To get a better understanding of these activities, the gene encoding cytochrome c7 from the sulfur-reducing bacterium Desulfuromonas acetoxidans was cloned from genomic DNA by PCR and expressed in Desulfovibrio desulfuricans G201. The expression system was based on the cyc transcription unit from Desulfovibrio vulgaris Hildenborough and led to the synthesis of holocytochrome c7 when transferred by electrotransformation into the sulfate reducer Desulfovibrio desulfuricans G201. The produced cytochrome was indistinguishable from the protein purified from Desulfuromonas acetoxidans cells with respect to several biochemical and biophysical criteria and exhibited the same metal reductase activities as determined from electrochemical experiments. This suggests that the molecule was correctly folded in the host organism. Desulfovibrio desulfuricans produces functional multiheme c-type cytochromes from bacteria belonging to a different genus and may be considered a suitable host for the heterologous biogenesis of multiheme c-type cytochromes for either structural or engineering studies. This report, which presents the first example of the transformation of a Desulfovibrio desulfuricans strain by electrotransformation, describes work that is the first necessary step of a protein engineering program that aims to specify the structural features that are responsible for the metal reductase activities of multiheme cytochrome c7.

[Visual, auditory and somatosensory potentials in the diagnosis of vitamin B12 deficiency]. / Apport des potentiels évoqués visuels, auditifs et somesthésiques dans le diagnostic d'une carence en vitamine B12.

We describe visual, brain stem auditory, and somatosensory evoked (VEP, BAEP, SEP) in a 49-year old male patient presenting with subacute degeneration of the spinal cord due to vitamin B12 deficiency. Neurological signs included tetraplegia with a C4-C5 spinal cord compression that was unchanged after surgical decompression. Before treatment, the duration of the bilateral VEP was slightly increased, though their amplitude and morphology were not modified. BAEP were normal. However, abnormalities of SEP with loss of cortical potentials were noticed. Two months after initiation of the treatment, both VEP and SEP recorded in response to median nerve stimulation had improved, but there was still no cortical response to tibial nerve stimulation. Eighteen months later, VEP were normal and recovery of SEP in response to tibial nerve stimulation was observed; however, alterations of peripheral sensory and motor action potentials were still present. These findings are in good agreement with previously reported pathological changes in patients presenting with subacute combined degeneration. Similar abnormalities have been described in patients with multiple sclerosis. Evoked potentials in this case proved to be useful for the diagnosis and the evaluation of the efficacy of the treatment. These findings also suggest that demyelination of the posterior part of the spinal cord and peripheral axonal degeneration might be the main pathological changes related to vitamin B12 deficiency. The former, but not like the latter, were clearly responsive to the treatment.

[Importance of neuromuscular "jitter" under stimulation in the diagnosis of myasthenia gravis]. / Intérêt du "jitter" neuromusculaire sous stimulation pour le diagnostic de myasthénie.

Ninety five patients with global muscular weakness or purely extraocular weakness were included in a retrospective study. Electrical micro stimulation and single fiber electromyography were performed in all, for neuromuscular jitter evaluation in myasthenia gravis diagnosis. In our study, increased jitter was more often present (70% of generalised myasthenia gravis and 57% of ocular myasthenia gravis) than decrement after repetitive nerve stimulations (58% of generalised myasthenia gravis and 14% of ocular myasthenia gravis). Increased jitter was also found in non-myasthenic patients. With the aim of a better sensitivity and specificity of the electrophysiological diagnosis for myasthenia gravis a protocol is described.

A protein involved in co-ordinated regulation of inorganic carbon and glucose metabolism in the facultative photoautotrophic cyanobacterium Synechocystis PCC6803.

The involvement of a gene of Synechocystis PCC6803, icfG, in the co-ordinated regulation of inorganic carbon and glucose metabolism, was established. The icfG gene codes for a 72 kDa protein, which shows no homology with those registered in data libraries. Expression of icfG required glucose, the actual inducer probably being glucose-6-phosphate, and was independent of light and of the external inorganic carbon concentration. Mutants carrying an inactivated copy of icfG were constructed. Their growth characteristics were identical to those of the wild type under all regimes except in limiting inorganic carbon with glucose being present either before or after the transfer to the limiting conditions. These conditions completely prevented growth, both in the light and in the dark. The inhibition could be relieved by several intermediates of the tricarboxylic acid cycle. Assays of various enzymic activities related to inorganic carbon uptake and to its assimilation via either the Calvin cycle or phosphoenolpyruvate carboxylase did not reveal the level of action of IcfG. Possible models include a blockage of the assimilation of both carbon sources in the absence of IcfG, or the inhibition of Ci incorporation route(s) essential under limiting inorganic carbon conditions, even when glucose is present, and even in the dark.

Consumption of benzodiazepines in a French university hospital between 1980 and 1991.

The consumption of benzodiazepines in the Toulouse university hospital from 1980 to 1991 was investigated. During this period, total annual consumption of benzodiazepines as anxiolytics remained stable, whereas their prescription as hypnotics fell (-70%). Moreover, short half-life benzodiazepines as hypnotics were preferred to long half-life ones. In parallel, there was an enhancement in new (zopiclone, zolpidem, buspirone) and old (alimemazine, hydroxyzine) drugs' consumption, the ratio benefits/risks of which have not yet been well defined.