Nintendo® Wii Fit based sleepiness tester detects impairment of postural steadiness due to 24 h of wakefulness

A field-usable sleepiness tester could reduce sleepiness related accidents. 15 subjects’ postural steadiness was measured with a Nintendo^® Wii Fit balance board every hour for 24 h. Body sway was quantified with complexity index, C_I, and the correlation between C_I and alertness predicted by a three-process model of sleepiness was calculated. The C_I group average was 8.9 ± 1.3 for alert and 7.9 ± 1.4 for sleep deprived subjects (p < 0.001, ρ = 0.94). The Wii Fit board detects the impairment of postural steadiness. This may allow large scale sleepiness testing outside the laboratory setting.     

Frataxin is reduced in Friedreich ataxia patients and is associated with mitochondrial membranes

Friedreich ataxia is a progressive neurodegenerative disorder caused by loss of function mutations in the frataxin gene. In order to unravel frataxin function we developed monoclonal antibodies raised against different regions of the protein. These antibodies detect a processed 18 kDa protein in various human and mouse tissues and cell lines that is severely reduced in Friedreich ataxia patients. By immunocytofluorescence and immunocytoelectron microscopy we show that frataxin is located in mitochondria, associated with the mitochondrial membranes and crests. Analysis of cellular localization of various truncated forms of frataxin expressed in cultured cells and evidence of removal of an N-terminal epitope during protein maturation demonstrated that the mitochondrial targetting sequence is encoded by the first 20 amino acids. Given the shared clinical features between Friedreich ataxia, vitamin E deficiency and some mitochondriopathies, our data suggest that a reduction in frataxin results in oxidative damage.      

Urinary bladder adenocarcinoma arising in a spina bifida patient

Urinary bladder adenocarcinomas are rare malignancies accounting for approximately 2.5% of all urothelial neoplasms. Intestinal metaplasia of the urothelium indicates the presence of intestinal-type goblet cells and was generally observed to coexist with or to precede the diagnosis of bladder adenocarcinomas. Controversy continues of whether intestinal metaplasia is an acquired precancerous lesion, secondary to different insults to the urothelium, or a concomitant lesion in glandular carcinogenesis. Patients with neurogenic bladders are particularly at risk for developing bladder cancer, mostly squamous cell carcinoma and rarely adenocarcinoma. In these patients, chronic irritation of the urothelium as well as long-term indwelling urinary catheters were the most significant risk factors. Spina bifida is a congenital developmental abnormality that may result in neurogenic bladder. There is only one previously reported case of urothelial carcinoma with associated squamous metaplasia of the bladder occurring in a spina bifida patient. We report the first case of bladder adenocarcinoma associated with intestinal metaplasia occurring in a spina bifida occulta patient. The patient had a complicated clinical course and suffered recurrent urinary tract infections, renal calculi, and urinary incontinence and was managed with intermittent as well as indwelling catheterization.     

Identification of 16 novel mutations in the argininosuccinate synthetase gene and genotype-phenotype correlation in 38 classical citrullinemia patients

Classical citrullinemia (CTLN1), a rare autosomal recessive disorder, is caused by mutations of the argininosuccinate synthetase (ASS) gene, localized on chromosome 9q34.1. ASS functions as a rate-limiting enzyme in the urea cycle. Previously, we identified 32 mutations in the ASS gene of CTLN1 patients mainly in Japan and the United States, and to date 34 different mutations have been described in 50 families worldwide. In the present study, we report ASS mutations detected in 35 additional CTLN1 families from 11 countries. By analyzing the entire coding sequence and the intron-exon boundaries of the ASS gene using RT-PCR and/or genomic DNA-PCR, we have identified 16 novel mutations (two different 1-bp deletions, a 67-bp insertion, and 13 missense) and have detected 12 known mutations. Altogether, 50 different mutations (seven deletion, three splice site, one duplication, two nonsense, and 37 missense) in 85 CTLN1 families were identified. On the basis of primary sequence comparisons with the crystal structure of E. coli ASS protein, it may be concluded that any of the 37 missense mutations found at 30 different positions led to structural and functional impairments of the human ASS protein. It has been found that three mutations are particularly frequent: IVS6-2A>G in 23 families (Japan: 20 and Korea: three), G390R in 18 families (Turkey: six, U.S.: five, Spain: three, Israel: one, Austria: one, Canada: one, and Bolivia: one), and R304W in 10 families (Japan: nine and Turkey: one). Most mutations of the ASS gene are "private" and are distributed throughout the gene, except for exons 5 and 12-14. It seems that the clinical course of the patients with truncated mutations or the G390R mutation is early-onset/severe. The phenotype of the patients with certain missense mutations (G362V or W179R) is more late-onset/mild. Eight patients with R86H, A118T, R265H, or K310R mutations were adult/late-onset and four of them showed severe symptoms during pregnancy or postpartum. However, it is still difficult to prove the genotype-phenotype correlation, because many patients were compound heterozygotes (with two different mutations), lived in different environments at the time of diagnosis, and/or had several treatment regimes or various knowledge of the disease.     

Systemic cholecystokinin differentially affects baro-activated GABAergic neurons in rat caudal ventrolateral medulla

Cholecystokinin (CCK) is released after a meal to promote digestion and satiety. Circulating CCK inhibits splanchnic sympathetic nerve activity (sSNA), which may contribute to postprandial increases in mesenteric blood flow. The CCK-induced sympathoinhibition occurs by activation of vagal afferent nerves and inhibition of a subset of presympathetic rostral ventrolateral medullary (RVLM) neurons. The present study sought to determine whether the caudal ventrolateral medulla (CVLM) may also play a role in the CCK-induced changes in sSNA. Rats were anesthetized with chloralose, artificially ventilated, paralyzed, and prepared for recording arterial pressure (AP), heart rate (HR), sSNA, and activity of individual CVLM neurons. Injection of CCK-8 (8-10 microg/kg, iv) decreased sSNA, AP, and HR. Most baro-activated CVLM neurons were excited by CCK (n = 25, 3.4-fold increase), whereas other baro-activated CVLM neurons were not affected (n = 7) or were inhibited (n = 3). A subset of baro-activated CVLM neurons that were activated (n = 8) or unaffected (n = 2) was confirmed to be GABAergic by the presence of GAD67 mRNA. Bilateral inhibition of the CVLM by microinjections of muscimol reversed the decreases in sSNA and AP to a prominent sympathoactivation and increase in AP (n = 18). These data suggest that systemic injection of CCK leads to the activation of most baro-activated GABAergic CVLM neurons and that the CVLM is essential for the production of CCK-induced inhibition of sSNA. The differential responses of baro-activated GABAergic CVLM neurons to CCK may contribute to the diverse responses of presympathetic RVLM neurons and sympathetic outflows observed with systemic CCK.     

Complete cDNA sequence of a South American isolate of potato virus X

The complete cDNA sequence corresponding to the genomic RNA of a South American strain of potato virus X (PVXc) is reported. The sequence (6432 nucleotides) contains five open reading frames coding for polypeptides with molecular weights of 165.3, 24.3, 12.3, 7.6 and 25.0 and displays an overall homology of 77.4% with those previously reported for two European isolates. Comparison of amino acid sequences shows an average homology of 87%. Two major domains of variability, located between amino acids 476-615 of ORF 1 and 64-100 of ORF 5, are identified. Sequence similarities between RNA stretches lying upstream of ORFs 2, 4 and 5, and at the 3'-non coding regions of PVX and other plus-strand RNA viruses are described.     

Identification of pro- and mature brain-derived neurotrophic factor in human saliva

Objective

Growth factors, including brain-derived neurotrophic factor (BDNF), are polypeptides that are involved in the maintenance, survival, and death of central and peripheral cells. Numerous growth factors have been identified in saliva and are thought to promote wound healing and maintenance of the oral epithelium. The aim of this study was to determine if BDNF is also found in human saliva.

Methods

Whole, unstimulated saliva samples (n = 30) were analyzed by SDS-PAGE and Western blot using an anti-human BDNF antibody. Proteolytic cleavage products were similarly assessed following the incubation of pooled saliva with N-glycanase F and plasmin. Subjects were also genotyped for the BDNF Val66Met single nucleotide polymorphism (SNP).

Results

These experiments revealed the presence of immunoreactive bands at 14, 32 and 34 kDa, corresponding to mature (mBDNF) and proBDNF, as well as a truncated pro-form at 24 kDa. Not every sample contained all forms of BDNF. Treatment with N-glycanase and plasmin reduced the size of the higher molecular weight bands, confirming the glycosylated pro-form of BDNF. mBDNF was detected significantly less often in subjects with the Val66Met SNP, compared to those without the polymorphism (χ² = 4.05; P < 0.05).

Conclusions

While the function of salivary BDNF still requires elucidation, these findings suggest that it may be possible to use saliva in lieu of blood in future studies of BDNF and the Val66Met polymorphism.     

Physical particle representation and generalized transformation theory

Glucocorticoid receptors with many properties suggesting their involvement in the hormonal induction of tyrosine aminotransferase have been detected in rat hepatoma tissue culture cells. These "specific receptors" approach saturation as the steroid concentrations required for maximal induction are reached. Inducer analogs influence cortisol binding to the specific receptors in direct relation to their influence on cortisol induction. The inducer association with and dissociation from specific receptors are rapid enough to account for the kinetics of induction and deinduction. Chromatographic studies suggest the specific receptors bind unaltered dexamethasone and cortisol. "Nonspecific" association of steroids with the cells also occurs and can be distinguished from specific binding.