Alterations of tibialis anterior muscle activation pattern in subjects with type 2 diabetes and diabetic peripheral neuropathy.

Diabetic peripheral neuropathy (DPN) is associated with loss of motor units (MUs), which can cause changes in the activation pattern of muscle fibres. This study investigated the pattern of muscle activation using high-density surface electromyography (HD-sEMG) signals from subjects with type 2 diabetes mellitus (T2DM) and DPN. Thirty-five adults participated in the study: 12 healthy subjects (HV), 12 patients with T2DM without DPN (No-DPN) and 11 patients with T2DM with DPN (DPN). HD-sEMG signals were recorded in the tibialis anterior muscle during an isometric contraction of ankle dorsiflexion at 50% of the maximum voluntary isometric contraction (MVIC) during 30-s. The calculated HD-sEMG signals parameters were the normalised root mean square (RMS), normalised median frequency (MDF), coefficient of variation (CoV) and modified entropy (ME). The RMS increased significantly (p = 0.001) with time only for the DPN group, while the MDF decreased significantly (p < 0.01) with time for the three groups. Moreover, the ME was significantly lower (p = 0.005), and CoV was significantly higher (p = 0.003) for the DPN group than the HV group. Using HD-sEMG, we have demonstrated a reduction in the number of MU recruited by individuals with DPN. This study provides proof of concept for the clinical utility of this technique for identifying neuromuscular impairment caused by DPN.

Prophylactic use of clopidogrel in paediatric cardiac patients.

Thromboembolic complications in infants with congenital heart defects are common despite inhibition of platelet function with acetylsalicylic acid (ASS). Yet there is still insufficient pharmacologic data on the use of clopidogrel in infants. The adult dose of 75 mg/d is significantly higher than the dose lately recommended in infants (0.2 mg/kg/d). Moreover, we know of nonresponders to both acetylsalicylic acid and clopidogrel. Normal coagulation tests fail to identify those patients.Prospective monocentric study on 14 children (median age 5, range 0.7-84 months, 9 male, 5 female). Shunt thrombosis had occurred in 4 infants on ASS therapy. Seven days after starting clopidogrel (0.2 mg/kg/d), platelet function was tested by stimulation with ADP (4 and 10 µmol/l). We considered the range for the clopidogrel effect to be optimal if the maximum aggregation on ADP 4 µmol/l was between 30-50%.Clopidogrel 0.18-0.24 mg/kg/d in addition to ASS 2-4 mg/kg/d resulted in effective inhibition of platelet function in 93% (ADP 4 µmol/l: median 38%, range 30-63). All patients were responders. We observed neither any thromboembolic events nor severe bleeding episodes during the median 11-month follow-up period (range 1-30 mo).Testing platelet function makes clopidogrel dosing safer, and simplifies therapy adjustments in long-term treatment. A clopidogrel dose of 0.2 mg/kg/d was safe and effective in combination with ASS in this small patient cohort.

Compound heterozygous mutations in 2 siblings with Hermansky-Pudlak syndrome type 1 (HPS1).

BACKGROUND: Hermansky-Pudlak syndrome (HPS) is a rare autosomal recessive disorder causing oculocutaneous albinism, bleeding disorder and ceroid lipofuscinosis. Platelets from HPS patients are characterized by the absence of dense (delta)-bodies. There are eight known human HPS GENES (HPS1-HPS8), each leading to a particular clinical HPS subtype. Restrictive lung disease, granulomatous colitis and cardiomyopathy have been described in HPS1 patients. PATIENTS: We identified HPS1 in Russian and in German siblings. All four patients show a typical HPS phenotype. The two older Russian patients demonstrate excessive bleeding after tooth extractions, recurrent epistaxis and hematomas. The two younger German patients suffer only from hematomas, so far. METHODS/RESULTS: Patients' platelets showed severe pathological agglutination/aggregation. Flow cytometry analysis demonstrated absence of platelet delta-granule secretion. Three different mutations in the HPS1 gene were found in the two families. Two mutations, p.H119delC and p.Q397delC identified in the Russian siblings had been previously described. The German siblings presented with a novel frameshift mutation (p.Q32_S33delCAGT) and the known p.Q397delC mutation. CONCLUSION: Patients with oculocutaneous albinism should be investigated for increased clinical bleeding symptoms. In case of increased bleeding symptoms, analyses of primary hemostasis should be initiated to confirm HPS. Molecular genetic investigations should be performed to distinguish the different subtypes of HPS which is important for therapy and prognosis.

Lepirudin treatment in a boy with suspected HIT II after surgery because of tetralogy of Fallot.

UNLABELLED: Heparin-induced thrombocytopenia (HIT II) in childhood is rare. Suspected HIT II requires immediate diagnostic and therapeutic measures in order to avoid potentially life threatening complications. Heparin must be stopped immediately. We report on a 6-year old boy who required cardiac surgery due to tetralogy of Fallot. To our knowledge he had been exposed to heparin for the first time during cardiac catheterization on the day before surgery. Preoperatively, platelet count was normal. Postoperatively (3 days after heparin exposure), he developed pulmonary and renal failure and required inotropic cardiac support and dialysis. He also developed progressive (severe) thrombocytopenia under heparin therapy on day 2-3 postoperatively. The dialysis filter required daily exchanges due to clotting despite increasing heparin doses. The first ELISA for HIT on postop day 4 was negative. 3 days later a repeated test was positive. Von Willebrand factor antigen and D-dimers were markedly increased. The patient was immediately switched to lepirudin and subsequently stabilized slowly. No major systemic thrombosis occurred. After lepirudin treatment for 6 weeks the patient was fully recovered and HIT II-testing was negative again. CONCLUSION: In children with progressive thrombocytopenia in the setting of heparin exposure and signs of major or micro thrombosis HIT II must be ruled out. Even if a first early test turns out negative repeated testing should be performed. Lepirudin anticoagulation is effective and should be monitored correctly. Platelet transfusion should be avoided in HITII.

Has repetitive transcranial magnetic stimulation (rTMS) treatment for depression improved? A systematic review and meta-analysis comparing the recent vs. the earlier rTMS studies.

OBJECTIVE: To investigate whether the recent repetitive transcranial magnetic stimulation (rTMS) studies on depression using new parameters of stimulation have shown improved clinical results. METHOD: We performed a systematic review and a meta-analysis of the rTMS studies on depression published in the past 12 months comparing these results with an earlier meta-analysis that analyzed the results of the initial rTMS studies on depression. RESULTS: Using our inclusion criteria, we selected the meta-analysis of Martin [Br J Psychiatry (2003) Vol. 182, 480-491] that included 13 studies (324 patients) and five studies for the recent meta-analysis (274 patients). The pooled effect size (standardized mean difference between pretreatment vs. post-treatment) from the random effects model was -0.76 (95% confidence interval, CI, -1.01 to -0.51). This result was significantly larger than that of the earlier meta-analysis (-0.35, 95% CI -0.66 to -0.04). CONCLUSION: Our findings suggest that recent rTMS clinical trials have shown larger antidepressant effects when compared with the earlier studies.

Restriction fragment length polymorphism of rRNA operons for discrimination and intergenic spacer sequences for cataloging of Bacillus subtilis sub-groups.

Restriction fragment length polymorphism of rRNA operons (RFLP) and 16S-23S rRNA intergenic region (ISR) sequences of Bacillus subtilis subsp. subtilis, B. subtilis subsp. spizizenii, and B. atrophaeus were compared. ISR sequences of the B. subtilis subspecies were extremely similar (W23 versus 168 rrn H, J, G,W; 96.8%; rrn D, E; 98.4%; rrnB; 97.9%) and, therefore, not useful for their differentiation. However, RFLP of rRNA operons of the B. subtilis subspecies were distinct in terms of numbers and organization within the genome (e.g. the 168 sub-group generally contained 8.3- and 8.0-kb fragments absent in the W23 sub-group). The more distantly related B. atrophaeus was distinct from both B. subtilis subspecies in terms of ISR sequence and rRNA operon number and organization. RFLP of rRNA operons discriminates the two sub-groups of Bacillus subtilis that are indistinguishable by ISR sequence. However, ISR sequence defines the relatedness of B. subtilis to other species (e.g. B. atrophaeus) within the genus Bacillus.

Bacillus pycnus sp. nov. and Bacillus neidei sp. nov., round-spored bacteria from soil.

Bacillus sphaericus sensu lato currently consists of seven or more groups of unrelated taxa, one of which is B. sphaericus sensu stricto and another of which is Bacillus fusiformis. Members of two groups (groups 6 and 7), in common with all other B. sphaericus-like organisms, are unable to grow anaerobically or to use common hexoses, pentoses and hexitols as sources of carbon, have G+C contents of 34-36 mol % and form round spores. Groups 6 and 7 can be differentiated from other B. sphaericus-like organisms by low DNA relatedness and by variations in whole-cell fatty acid composition. Unique characteristics of group 6 include the ability to oxidize beta-hydroxybutyrate, the non-requirement for biotin and thiamin and failure to grow in 5% NaCl. Distinctive traits of group 7 include the inability to oxidize pyruvate and a requirement for biotin, thiamin and cystine for growth. These data show that groups 6 and 7 represent two novel species, for which the names Bacillus pycnus sp. nov. and Bacillus neidei sp. nov., respectively, are proposed; the corresponding type strains are NRRL NRS-1691T (= JCM 11075T) and NRRL BD-87T (= JCM 11077T).

Free radical spin trap alpha-phenyl-N-tert-butyl-nitron inhibits caspase-3 activation and reduces brain damage following a severe forebrain ischemic injury.

It has been documented that alpha-phenyl-N-tert-butyl-nitron (PBN) possesses a potent neuroprotective effect when administered after transient focal cerebral ischemia. However, contradicting results were reported regarding its effect in transient global ischemia. To further elucidate the mechanism of PBN action, we have studied the effect of PBN on animal survival, histopathological outcome, and activation of caspase-3 following 30 min of global ischemia in vehicle- and PBN-treated rats. The results showed that 30 min of global ischemia was such a severe insult that no animal could survive beyond 2 d of reperfusion. Histopathological evaluation showed severe tissue edema and microinfarct foci in the neocortex and thalamus. Close to 100% damage was observed in the stratum and hippocampal CA1, CA3, and dentate gyrus subregions. Postischemic PBN treatment significantly enhanced animal survival and reduced damage in the neocortex, thalamus, and hippocampus. Immunohistochemistry demonstrated that caspase-3 was activated following ischemia in the striatum and the neocortex. PBN suppressed the activation of caspase-3 in both structures. It is concluded that PBN is a potent neuroprotectant against both focal and global ischemia; besides its function as a free radical scavenger, PBN may reduce ischemic brain damage by blocking cell death pathways that involve caspase-3 activation.

Bacillus sonorensis sp. nov., a close relative of Bacillus licheniformis, isolated from soil in the Sonoran Desert, Arizona.

Eight Bacillus strains isolated from Sonoran Desert soil were shown to belong to a previously unidentified species, for which the name Bacillus sonorensis sp. nov. is proposed. The type strain is strain L87-10T (= NRRL B-23154T). On the basis of phenotypic and genetic data, B. sonorensis is most closely related to Bacillus licheniformis. B. sonorensis can be distinguished from B. licheniformis by salt tolerance, pigmentation, multilocus enzyme electrophoresis, reassociation of genomic DNA and sequence differences in protein-coding genes and 16S rRNA.

Frequency and ethnic distribution of the common DHCR7 mutation in Smith-Lemli-Opitz syndrome.

Smith-Lemli-Opitz syndrome (SLOS) is an inherited multiple malformation syndrome caused by enzymatic deficiency of 3beta-hydroxysterol-Delta(7)-reductase (DHCR7). SLOS is thought to be most common among European Caucasians, with an incidence of 1 in 20,000 to 1 in 30,000 births. To define the carrier rate and ethnic distribution of SLOS, we screened DNA samples from 2,978 unrelated individuals for the most common SLOS mutation (IVS8-1G-->C). Twenty-four heterozygotes of the IVS8-1G-->C mutation were detected in 2,978 individuals of European Caucasian and Black backgrounds. For European Caucasians, the carrier rate for SLOS may be as high as 1 in 30, suggesting an incidence of 1 in 1,700 to 1 in 13,400. This high number is supported by the recent observation of newborn and prenatal incidence of 1 in 22,000 in the Caucasian population. Ours is the first report of the IVS8-1G-->C mutation in persons of African ancestry. Published 2001 Wiley-Liss, Inc.

Phylogeny of Bacillus sphaericus-like organisms.

The mesophilic round-spored bacteria embrace four species, namely Bacillus sphaericus, Bacillus fusiformis, Bacillus silvestris and Bacillus pasteurii. Although not displayed by all strains, mosquito pathogenicity is a noteworthy characteristic of B. sphaericus sensu lato. Phylogenetic analysis based on 16S rDNA sequences from 58 strains identified as B. sphaericus was used to examine the genetic heterogeneity of the taxon. Results from sequence analysis were compared with whole-cell fatty acid profiles and other phenotypic determinations. The B. sphaericus-like strains segregated into seven distinct clusters in a phylogenetic tree generated from 16S sequences. One cluster represented B. sphaericus and another B. fusiformis. A third cluster containing all of the pathogenic strains was closely related to, or was possibly part of, the B. fusiformis group. The remaining four groups were distinct and represented unnamed taxa that were more closely related to B. sphaericus and B. fusiformis than to the psychrophilic round-spored species, Bacillus globisporus and Bacillus psychrophilus. Groups based on phenotypic analysis corresponded to the 16S rDNA phylogenetic clusters. Data showed that B. sphaericus was genetically and phenotypically a highly heterogeneous taxon including at least seven genetically distinct taxa. The pathogenic strains were members of a distinct group and not of the species B. sphaericus sensu stricto. This heterogeneity partially accounts for the apparent variability of mosquito pathogenicity among B. sphaericus strains.

Lactobacillus arizonensis sp. nov., isolated from jojoba meal.

Five strains of simmondsin-degrading, lactic-acid-producing bacteria were isolated from fermented jojoba meal. These isolates were facultatively anaerobic, gram-positive, non-motile, non-spore-forming, homofermentative, rod-shaped organisms. They grew singly and in short chains, produced lactic acid but no gas from glucose, and did not exhibit catalase activity. Growth occurred at 15 and 45 degrees C. All strains fermented cellobiose, D-fructose, D-galactose, D-glucose, lactose, maltose, D-mannitol, D-mannose, melibiose, D-ribose, salicin, D-sorbitol, sucrose and trehalose. Some strains fermented L-(-)-arabinose and L-rhamnose. D-Xylose was not fermented and starch was not hydrolysed. The mean G+C content of the DNA was 48 mol%. Phylogenetic analyses of 16S rDNA established that the isolates were members of the genus Lactobacillus. DNA reassociation of 45% or less was obtained between the new isolates and the reference strains of species with G+C contents of about 48 mol%. The isolates were differentiated from other homofermentative Lactobacillus spp. on the basis of 16S rDNA sequence divergence, DNA relatedness, stereoisomerism of the lactic acid produced, growth temperature and carbohydrate fermentation. The data support the conclusion that these organisms represent strains of a new species, for which the name Lactobacillus arizonensis is proposed. The type strain of L. arizonensis is NRRL B-14768T (= DSM 13273T).

Nocturnal tarsier retina has both short and long/medium-wavelength cones in an unusual topography.

The evolutionary position of tarsiers with respect to primates is still debated. The type of photoreceptors in the nocturnal Tarsius spectrum retina has been compared with the nocturnal New World monkey Aotus trivulgaris and the Old World monkey Macaca nemestrina by using immunocytochemical labeling for antisera known to be specific for primate cone and rod proteins. In all three species, antisera to long/medium (L/M) -wavelength specific cone opsin and cone-specific alpha-transducin detected a single row of cones. Only Macaca and tarsier retina contained cones labeled by antiserum to short (S) -wavelength specific cone opsin. Tarsier rod cell bodies were 6-12 deep, depending on retinal eccentricity. Tarsier central cones had 2-microm-wide outer (OS) and inner segments, which came straight off the cell body. Cone morphology differed little from rods except OS were shorter. Macaca cones labeled for 7G6 and calbindin, Aotus cones did not label for calbindin, and Tarsius cones did not label for 7G6 or calbindin. In tarsier retinal whole-mounts, peak cone density ranged from 11,600-14,200/cones mm(2). The 11- to 12-mm-wide peak region centered roughly on the optic disc, although foveal counts remain to be completed. Density decreased symmetrically to a far peripheral band of 4,200-7, 000/cones mm(2). In contrast, S cone density was very low in central retina (0-300/mm(2)), rose symmetrically with eccentricity, and peaked at 1,100-1,600/mm(2) in a 2- to 3-mm-wide zone in the far periphery. In this zone, S cones were 9-14% of all cones. L/M cones were regularly spaced, whereas S cones showed no regular distribution pattern. Although the functional characteristics of the tarsier S and L/M cone systems are yet to be determined, tarsier cone proteins and distribution have some similarities to both New and Old World monkey retinas.