[Symptoms of HELLP syndrome due to vitamin B12 deficiency: report of seven cases]. / Pseudo-HELLP syndrome par carence en vitamine B12: à propos de sept cas.

INTRODUCTION: HELLP syndrome is characterized by generalised thrombotic microangiopathy predominant in the liver. Many investigators consider HELLP syndrome to be a variant of severe preeclampsia. Several other conditions have similar laboratory findings in common with HELLP syndrome and should be eliminated before pregnancy termination. PATIENTS AND METHODS: The authors report seven observations of patients with biological criteria that mimic HELLP syndrome secondary to severe vitamin B12 deficiency. CONCLUSION: Vitamin B12 or B9 deficiency developed during pregnancy have laboratory findings similar to those of HELLP syndrome.

[Staphylococcic necrotizing pneumopathy due to Panton-Valentine leukocidin toxin with good outcome]. / Pneumopathie nécrosante staphylococcique productrice de leucocidine de Panton-Valentine d'évolution favorable.

Panton-Valentine leukocidin (PLV) is a toxin produced by Staphylococcus aureus. Previously described as responsible for furunculoses and cutaneous abscesses, it was recently found to cause necrotizing pneumonia, generally lethal. We describe a case of necrotizing pneumonia caused by S. aureus containing PLV with an atypical form (bubble form), which had a good outcome despite several risk factors for death: hemoptysis, leukopenia, erythrodermia.

[Gamma-delta T-cell lymphoma: outcome of a hyperactive malarial splenomegaly?]. / Lymphome T gamma-delta: complication possible d'une splénomégalie palustre hyperactive?

We report a gamma-delta T-cell lymphoma, in a male patient having a hyperactive malarial splenomegaly. The immunological disorder caused by chronic antigenic stimulation could be one of the causes leading to the occurrence of such hematologic disease. The prognosis of this type of lymphoma remains poor, partly due to delayed diagnosis. Therefore, it seems appropriate to investigate any atypical hyperactive malarial splenomegaly. In our observation, the macrophagic activation syndrome led us to discover the lymphoma.

Elevated aluminium concentration in acidified headwater streams lowers aquatic hyphomycete diversity and impairs leaf-litter breakdown.

Aquatic hyphomycetes play an essential role in the decomposition of allochthonous organic matter which is a fundamental process driving the functioning of forested headwater streams. We studied the effect of anthropogenic acidification on aquatic hyphomycetes associated with decaying leaves of Fagus sylvatica in six forested headwater streams (pH range, 4.3-7.1). Non-metric multidimensional scaling revealed marked differences in aquatic hyphomycete assemblages between acidified and reference streams. We found strong relationships between aquatic hyphomycete richness and mean Al concentration (r = -0.998, p < 0.0001) and mean pH (r = 0.962, p < 0.002), meaning that fungal diversity was severely depleted in acidified streams. By contrast, mean fungal biomass was not related to acidity. Leaf breakdown rate was drastically reduced under acidic conditions raising the issue of whether the functioning of headwater ecosystems could be impaired by a loss of aquatic hyphomycete species.

[Catastrophic antiphospholipid syndrome after ovulation induction]. / Syndrome catastrophique des antiphospholipides après induction d'ovulation.

INTRODUCTION: The catastrophic antiphospholipid syndrome (CAPS) is a rare expression of the antiphospholipid syndrome (APLS). The all predicting factors of happening of CAPS are not yet discovered. Some women presenting an APLS with infertility have recourse to ovulation induction (OI). EXEGESIS: After an OI, a woman is admitted for acute renal failure, hypertension, seizures, respiratory failure. History and immunologic tests are in favour of APLS. Renal biopsy highlights a thrombotic microangiopathy. Diagnosis of CAPS is made. Patient improves after respiratory assistance, parenteral treatment for hypertension and anticoagulant therapy. CONCLUSION: IO seems to be on of the factors which leads to CAPS. To avoid such consequences, it's essential to know the history and the immunological status of the patients having recourse to this treatment to take care of these risked pregnancies.

[Muscle diseases in an internal medicine department]. / Diagnostic des maladies musculaires dans un service de médecine interne.

PURPOSE: (1) To describe the causes of muscular symptoms in patients undergoing a muscle biopsy in an internal medicine department; (2) to evaluate the diagnostic value of electromyography (EMG), CPK level and muscle biopsy. METHODS: A retrospective study including 90 patients from June 1995 to March 2001. RESULTS: The diagnosis were: inflammatory diseases (n = 35), non-organic (n = 24), peripheral neuropathy (n = 8), undetermined organic diseases (n = 7), metabolic diseases (n = 5), toxic diseases (n = 4), infectious diseases (n = 4), amyloidosis (n = 3). Diagnosis value of EMG, CPK and biopsy for organicity were: sensibility: 82%, 47% and 29%; specificity: 46%, 91%, 100%; positive predictive value: 78%, 94% and 100%; negative predictive value: 50%, 40% and 36%. Muscle biopsy is always normal when CPK and EMG are normal. It allows a diagnosis in one out of three cases if EMG and CPK are differing. It is also indicated when CPK are normal and EMG is myogenic. CONCLUSION: Numerous diseases account for muscular symptoms. The low rate of diagnostic muscle biopsy imposes a comprehensive clinical approach of the patient and justify the implication of internal medicine physicians in his care. Early intervention of a psychosomatic medicine practitioner in the diagnostic procedure should be evaluated to diminish the number of non-contributory biopsies.

Competitive interaction between two aquatic hyphomycete species and increase in leaf litter breakdown.

Aquatic hyphomycete species produce large numbers of conidia which rapidly colonize the leaf litter that falls into rivers during autumn. Our objective was to understand how a species which produces many fewer conidia than another in laboratory conditions can nevertheless be codominant in a natural setting. In microcosm studies with two pioneer dominant species, Flagellospora curvula and Tetrachaetum elegans, inoculated on alder leaves, we first verified that the ratio of the conidium production of both species (6 to 7:1) was inverse to that of individual conidial masses (1:7) as previously described. Calculating the percentage of leaf mass loss that corresponds to 1A mg of conidial mass produced, the combination of the two species produced 2.9-fold more loss than the mean of each species. By contrast, the reproductive biomasses of F. curvula and T. elegans were 5.2- and 2.6-fold lower, respectively. As a result, the conidium production of F. curvula in the combination was only 3.2-fold that of T. elegans instead of 6- to 7-fold in pure culture. In a mixed culture of the two species, T. elegans conidia had a high germination potential (>90%) whereas the proportion of germinated F. curvula conidia was only 50%. Moreover, T. elegans reduced the area on which F. curvula could grow on poor and rich solid media. These results indicate that the dominance of F. curvula conidia in the river may be partly controlled by T. elegans and suggest that a negative interaction between microfungi may have a positive effect on the ecosystem functioning.

Automatic identification of motor unit action potential trains from electromyographic signals using fuzzy techniques.

A technique is proposed that allows automatic decomposition of electromyographic (EMG) signals into their constituent motor unit action potential trains (MUAPTs). A specific iterative algorithm with a classification method using fuzzy-logic techniques was developed. The proposed classification method takes into account imprecise information, such as waveform instability and irregular firing patterns, that is often encountered in EMG signals. Classification features were determined by the combining of time position and waveform information. Statistical analysis of inter-pulse intervals and spike amplitude provided an accurate estimation of features used in the classification step. Algorithm performance was evaluated using simulated EMG signals composed of up to six different discharging motor units corrupted with white noise. The algorithm was then applied to real signals recorded by a high spatial resolution surface EMG device based on a Laplacian spatial filter. On six groups of 20 simulated signals, the decomposition algorithm performed with a maximum and an average mean error rate of 2.13% and 1.37%, respectively. On real surface EMG signals recorded at different force levels (from 10% to 40% of the maximum voluntary contraction), the algorithm correctly identified 21 MUAPTs, compared with the 29 MUAPTs identified by an experienced neurophysiologist. The efficiency of the decomposition on surface EMG signals makes this method very attractive for non-invasive investigation of physiological muscle properties. However, it can also be used to decompose intramuscularly recorded EMG signals.

Neurological presentation in pediatric patients with congenital disorders of glycosylation type Ia.

OBJECTIVE: Congenital disorders of glycosylation (CDG), formerly called carbohydrate-deficient glycoprotein syndromes, constitute a newly identified group of multisystem disorders characterized by defective glycosylation of N-glycosylated proteins. The objective of this work was to describe precisely neurological findings in patients with type Ia CDG (CDG-Ia) and to compare our results with the literature. STUDY DESIGN: We retrospectively reviewed neurological and neurodevelopmental, neuroimaging, and genetic features in ten patients with CDG-Ia who mainly presented with neurological abnormalities during childhood and therefore were referred to a neuropediatrician or a neurogeneticist. RESULTS: Neurological manifestations had a static clinical course, dominated by mental retardation and cerebellar dysfunction, and acute episodes: stroke-like episodes and seizures. However, microcephaly, retinopathy, and polyneuropathy were progressive. All patients had severe global neurodevelopmental delay: only one was able to walk alone at ten years of age and only one could read. Marked heterogeneity in manifestations and delay of diagnosis was noted across the patients. Cerebellar hypoplasia was found by magnetic resonance imaging in all ten patients and olivopontocerebellar hypoplasia in four patients. As in the literature, there was no clear phenotype-mutation correlation. CONCLUSION: Our findings confirm the importance of a precise and complete description of the neurological and neuroradiological phenotype delineating the phenotype of CDG-Ia to increase the likelihood of diagnosing the disease.

Effects of stream acidification on fungal biomass in decaying beech leaves and leaf palatability.

We examined the effect of surface water acidification on rates of decomposition, ergosterol concentrations (as a measure of fungal biomass), and palatability to shredders of common beech leaves (Fagus sylvatica L.) in five mountain streams (pH 4.7-7.1). Leaf decomposition was significantly faster in the circumneutral streams (pH 6.4-7.1; k > or = 0.00175 d(-1)), when compared to acidic streams (pH 4.7-4.9; k < or = 0.00100 d(-1)). Fungal biomass showed no particular trend along the acidification gradient except that it peaked earlier in the stream closest to neutrality. Leaf palatability, measured as the feeding activity of the leaf-shredding amphipod Gammarus fossarum Koch, varied with the exposure time in the streams. Except for the higher palatability of leaves exposed during 6 weeks at the highest pH, patterns among streams were mostly similar. These results suggest that reduced processing rates in the most acidic streams were not related to differences in fungal biomass associated with decomposing leaves and that microbial conditioning was only slightly delayed by acidification. Possible effects of low pH and related variables (Ca, Al) on microbial decomposition and detritivorous macroinvertebrates are discussed to clarify the inhibition of beech leaf decomposition in the studied systems.

[Oral histoplasmosis 34 years after return of Africa]. / Une histoplasmose du plancher buccal 34 ans après un retour d'Afrique.

INTRODUCTION: Histoplasmosis is a tropical fungal infection sharing many similarities with tuberculosis: the transmission by air dropplets, the usually asymptomatic primary-infection, the disseminated infection encountered among immunosuppressed patients and the granulomatous pathological lesions. In France, histoplasmosis is uncommon and may be misdiagnosed as tuberculosis. OBSERVATION: A 78 years old male patient presents with a raspberry-like lesion of the mouth causing difficulties to eat and weight loss of 14 kg. The diagnosis of tuberculosis is evoked because of the presence of a giant-cell granuloma in one of the biopsies. The histoplasmosis serology, requested because the patient stayed in Africa, is positive. Revisions of the pathology put into evidence the presence of spores in histiocytes confirming diagnosis of histoplasmosis. The treatment with itraconazole is effective. CONCLUSION: Histoplasmosis is a differential diagnosis of tuberculosis, especially in endemic regions. The histoplasmosis serology can be useful. The reference in diagnosis examinations keeps being the microscopic observation of spores and their mycological growth.

Symptomatic macroglossia and tongue myositis in polymyositis: treatment with corticosteroids and intravenous immunoglobulin.

Symptomatic macroglossia occurs in some rare congenital muscle diseases, such as Becker's and Duchenne's dystrophies or Pompe's disease. Herein we describe a case of symptomatic macroglossia with myositis of the tongue occurring in a patient with polymyositis. Tongue myositis was evidenced by dysarthria, frequent biting during mastication, swallowing difficulties without aspiration, and noisy breathing. Magnetic resonance imaging showed homogeneous hypertrophy of the tongue, especially the mouth's floor muscles. The diagnosis of tongue myositis was established by electromyography and biopsy. No other cause for the macroglossia was found. Symptoms resolved quickly with corticosteroid and intravenous immunoglobulin treatment. To our knowledge, this is the first reported case of symptomatic tongue myositis occurring in the course of polymyositis.

Effect of culture conditions on ergosterol as an indicator of biomass in the aquatic hyphomycetes.

Ergosterol is a membrane component specific to fungi that can be used to estimate fungal biomass using appropriate factors of conversion. Our objectives were to determine the limits of use of ergosterol content as a measure of biomass for aquatic hyphomycetes, and to evaluate a previously established ergosterol-to-biomass conversion factor. We varied inoculum quality, growth medium, and degree of shaking of four aquatic hyphomycete species. In cultures inoculated with homogenized mycelium, we found a significant effect of shaking condition and culture age on ergosterol content. In liquid cultures with defined medium, ergosterol content reached 10 to 11 microg/mg of mycelium (dry mass) and varied by factors of 2.2 during exponential growth and 1.3 during stationary phase. The increase in ergosterol content during exponential phase could be attributed, at least in part, to rapid depletion of glucose. Oxygen availability to internal hyphae within the mycelial mass is also responsible for the differences found between culture conditions. Ergosterol concentration ranged from 0.8 to 1.6 microg/mg in static cultures inoculated with agar plugs. Ergosterol content varied by a factor of 4 in two media of different richnesses. For different combinations of these parameters, strong (r(2) = 0.83 to 0.98) and highly significant (P << 0.001) linear relationships between ergosterol and mycelial dry mass (up to 110 mg) were observed. Overall, the ergosterol content varied by a factor of 14 (0.8 to 11 mg/g). These results suggest that care must be taken when the ergosterol content is used to compare data generated in different field environments.

Temperature and sporulation of aquatic hyphomycetes.

Temperature appears to be an important factor affecting the occurrence and distribution of aquatic hyphomycetes, the dominant leaf litter-decomposing fungi in streams. We compared conidium production by eight species of aquatic hyphomycetes grown on yellow poplar leaves in stream-simulating microcosms at three temperatures (15, 20, and 25 degrees C). The greatest conidium production occurred at 15 degrees C for one species, 20 degrees C for two species, and 25 degrees C for two species. Two species produced similar numbers of conidia at 20 and 25 degrees C, and one species produced similar numbers of conidia at all three temperatures. Linear growth rates were determined on malt extract agar. Six species had the same pattern of temperature responses for growth on malt extract agar as for sporulation on leaves, as shown by the positive correlations between the two parameters at the three temperatures. The species examined also exhibited differences in number of conidia produced from a similar amount of leaf material at a given temperature. These differences appeared to be due primarily to differences in individual conidium mass (determined by weighing conidia produced from cultures), as shown by the relationship of the type Y = k/X (r = 0.96), where Y is the number of conidia produced, X is the individual conidium mass in milligrams, and k is a constant empirically determined to be 2.11. This finding supports the hypothesis that aquatic hyphomycetes allocate similar amounts of their resources to reproduction but vary with respect how these resources are partitioned into reproductive units (conidia).

Role of CD3gamma and CD3delta cytoplasmic domains in cytolytic T lymphocyte functions and TCR/CD3 down-modulation.

TCR engagement leads to down-modulation of TCR/CD3 complexes from the T cell surface. The importance of this effect in T cell physiology is unknown. Here, we characterized a CTL clone deficient in TCR/CD3 surface expression that had lost both CD3delta and CD3gamma mRNA, allowing us to address the role of these chains in the assembly, signaling, and dynamics of the TCR/CD3 complex. Expression of either CD3delta or CD3gamma alone failed to reconstitute surface expression of the TCR/CD3 complex, but reconstitution with a cytoplasmically truncated CD3delta (delta t) and a native (gamma) or cytoplasmically truncated (gamma t) human CD3gamma led to reexpression of TCR/CD3 complexes in both cases. This indicated that CD3delta and CD3gamma assume specific functions in TCR/CD3 assembly independently of their cytoplasmic domains. The delta t gamma t variant specifically killed target cells, expressed the IFN-gamma gene in response to Ag, and produced TNF-alpha in response to anti-CD3 mAb, but it was affected in CD3 ligand-induced TCR/CD3 down-modulation. Both PMA- and CD3 ligand-induced TCR/CD3 down-modulation were defective in the delta t gamma t variant, whereas the delta t gamma variants were unaffected, and previously described delta gamma t variants were affected only in PMA-induced down-modulation. Specific protein kinase C (PKC) inhibitors indicated that PMA- but not CD3 ligand-induced down-modulation was dependent on PKC activity. Thus, amino acid sequences present in either the CD3delta or CD3gamma cytoplasmic domain control ligand-induced TCR/CD3 down-modulation, and neither these sequences nor this property are required for cytolysis and IFN-gamma gene expression in response to Ag.

Comparison of ATP and ergosterol as indicators of fungal biomass associated with decomposing leaves in streams.

ATP and ergosterol were compared as indicators of fungal biomass associated with leaves decomposing in laboratory microcosms and streams. In all studies, the sporulation rates of the fungi colonizing leaves were also determined to compare patterns of fungal reproductive activity with patterns of mycelial growth. During leaf degradation, ATP concentrations exhibited significant, positive correlations with ergosterol concentrations in the laboratory and when leaves had been air dried prior to being submerged in a stream. However, when freshly shed leaves were submerged in a stream, concentrations of ATP and ergosterol were negatively correlated during degradation. This appeared to be due to the persistence of leaf-derived ATP in freshly shed leaves during the first 1 to 2 weeks in the stream. Estimates of fungal biomass from ergosterol concentrations of leaf litter were one to three times those calculated from ATP concentrations. ATP, ergosterol, and sporulation data generally provided similar information about the fungi associated with decomposing leaves in streams during periods when fungi were growing. Ergosterol concentrations provide a more accurate indication of fungal biomass in situations in which other organisms make significant contributions to ATP pools.

Ergosterol-to-Biomass Conversion Factors for Aquatic Hyphomycetes.

Fourteen strains of aquatic hyphomycete species that are common on decaying leaves in running waters were grown in liquid culture and analyzed for total ergosterol contents. Media included an aqueous extract from senescent alder leaves, a malt extract broth, and a glucose-mineral salt solution. Concentrations of ergosterol in fungal mycelium ranged from 2.3 to 11.5 mg/g of dry mass. The overall average was 5.5 mg/g. Differences among both species and growth media were highly significant but followed no systematic pattern. Stationary-phase mycelium had ergosterol contents 10 to 12% lower or higher than mycelium harvested during the growth phase, but these differences were only significant for one of four species examined. Availability of plant sterols in the growth medium had no clear effect on ergosterol concentrations in two species tested. To convert ergosterol contents determined in field samples to biomass values of aquatic hyphomycetes, a general multiplicative factor of 182 is proposed. More accurate estimates would be obtained with species-specific factors. Using these in combination with estimates of the proportion of the dominant species in a naturally established community on leaves resulted in biomass estimates that were typically 20% lower than those obtained with the general conversion factor. Improvements of estimates with species-specific factors may be limited, however, by intraspecific variability in fungal ergosterol content.

Lignin degradation and humus formation in alluvial soils and sediments.

The contribution of lignin to the formation of humic compounds was examined in different environments of the terrestrial-aquatic interface in the Garonne River valley in southwestern France. Alluvial soils and submerged or nonsubmerged river and pond sediments containing alder, poplar, or willow [C-lignin]ligno-celluloses were incubated. After a 49-day incubation period, 10 to 15% of labeled lignins in alluvial soils was recovered as evolved CO(2). In nonsubmerged sediments, 10% of the applied activity was released as CO(2), and in submerged sediments, only 5% was released after 60 days of incubation. In the different alluvial soils and sediments, the bulk of residual activity (70 to 85%) remained in the two coarsest-grain fractions (2,000 to 100 and 100 to 50 mum). Only 2 to 6% of the residual activity of these two coarse fractions was recovered as humic and fulvic acids, except in the case of alder [C-lignin]lignocellulose, which had decomposed in a soil collected beneath alders. In this one 55% of the residual activity was extracted as humic substances from the 2,000- to 100-mum fraction. Humic and fulvic acids represented from 6 to 50% of the residual activity in the finest-grain fractions (50 to 20 and 20 to 0 mum). The highest percentages were obtained in soil collected beneath alders and in submerged pond sediment. The contribution of different groups of microorganisms, as well as nutrients and clay content, may influence humic-substance formation in such environments. Physical stability also may be an important factor for complex microbial activity involved in this process.