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Abstract Background Amyotrophic lateral sclerosis (ALS) is a fatal disorder involving the degeneration and loss of motor neurons. The mechanisms of motor neuron loss in ALS are unknown and there are no effective treatments. Defects in the distal axon and at the neuromuscular junction are early events in the disease course, and zebrafish provide a promising in vivo system to examine cellular mechanisms and treatments for these events in ALS pathogenesis. Results We demonstrate that transient genetic manipulation of zebrafish to express G93A-SOD1, a mutation associated with familial ALS, results in early defects in motor neuron outgrowth and axonal branching. This is consistent with previous reports on motor neuron axonal defects associated with familial ALS genes following knockdown or mutant protein overexpression. We also demonstrate that upregulation of growth factor signaling is capable of rescuing these early defects, validating the potential of the model for therapeutic discovery. We generated stable transgenic zebrafish lines expressing G93A-SOD1 to further characterize the consequences of G93A-SOD1 expression on neuromuscular pathology and disease progression. Behavioral monitoring reveals evidence of motor dysfunction and decreased activity in transgenic ALS zebrafish. Examination of neuromuscular and neuronal pathology throughout the disease course reveals a loss of neuromuscular junctions and alterations in motor neuron innervations patterns with disease progression. Finally, motor neuron cell loss is evident later in the disease. Conclusions This sequence of events reflects the stepwise mechanisms of degeneration in ALS, and provides a novel model for mechanistic discovery and therapeutic development for neuromuscular degeneration in ALS.

Abstract Background Vaccine literature indexing is poorly performed in PubMed due to limited hierarchy of Medical Subject Headings (MeSH) annotation in the vaccine field. Vaccine Ontology (VO) is a community-based biomedical ontology that represents various vaccines and their relations. SciMiner is an in-house literature mining system that supports literature indexing and gene name tagging. We hypothesize that application of VO in SciMiner will aid vaccine literature indexing and mining of vaccine-gene interaction networks. As a test case, we have examined vaccines for Brucella, the causative agent of brucellosis in humans and animals. Results The VO-based SciMiner (VO-SciMiner) was developed to incorporate a total of 67 Brucella vaccine terms. A set of rules for term expansion of VO terms were learned from training data, consisting of 90 biomedical articles related to Brucella vaccine terms. VO-SciMiner demonstrated high recall (91%) and precision (99%) from testing a separate set of 100 manually selected biomedical articles. VO-SciMiner indexing exhibited superior performance in retrieving Brucella vaccine-related papers over that obtained with MeSH-based PubMed literature search. For example, a VO-SciMiner search of "live attenuated Brucella vaccine" returned 922 hits as of April 20, 2011, while a PubMed search of the same query resulted in only 74 hits. Using the abstracts of 14,947 Brucella-related papers, VO-SciMiner identified 140 Brucella genes associated with Brucella vaccines. These genes included known protective antigens, virulence factors, and genes closely related to Brucella vaccines. These VO-interacting Brucella genes were significantly over-represented in biological functional categories, including metabolite transport and metabolism, replication and repair, cell wall biogenesis, intracellular trafficking and secretion, posttranslational modification, and chaperones. Furthermore, a comprehensive interaction network of Brucella vaccines and genes were identified. The asserted and inferred VO hierarchies provide semantic support for inferring novel knowledge of association of vaccines and genes from the retrieved data. New hypotheses were generated based on this analysis approach. Conclusion VO-SciMiner can be used to improve the efficiency for PubMed searching in the vaccine domain.

Abstract Background Reactive oxygen species (ROS) are known mediators of cellular damage in multiple diseases including diabetic complications. Despite its importance, no comprehensive database is currently available for the genes associated with ROS. Methods We present ROS- and diabetes-related targets (genes/proteins) collected from the biomedical literature through a text mining technology. A web-based literature mining tool, SciMiner, was applied to 1,154 biomedical papers indexed with diabetes and ROS by PubMed to identify relevant targets. Over-represented targets in the ROS-diabetes literature were obtained through comparisons against randomly selected literature. The expression levels of nine genes, selected from the top ranked ROS-diabetes set, were measured in the dorsal root ganglia (DRG) of diabetic and non-diabetic DBA/2J mice in order to evaluate the biological relevance of literature-derived targets in the pathogenesis of diabetic neuropathy. Results SciMiner identified 1,026 ROS- and diabetes-related targets from the 1,154 biomedical papers (http://jdrf.neurology.med.umich.edu/ROSDiabetes/). Fifty-three targets were significantly over-represented in the ROS-diabetes literature compared to randomly selected literature. These over-represented targets included well-known members of the oxidative stress response including catalase, the NADPH oxidase family, and the superoxide dismutase family of proteins. Eight of the nine selected genes exhibited significant differential expression between diabetic and non-diabetic mice. For six genes, the direction of expression change in diabetes paralleled enhanced oxidative stress in the DRG. Conclusions Literature mining compiled ROS-diabetes related targets from the biomedical literature and led us to evaluate the biological relevance of selected targets in the pathogenesis of diabetic neuropathy.

Abstract Background Painful Diabetic Neuropathy (PDN) affects more than 25% of patients with type 2 diabetes; however, the pathogenesis remains unclear due to lack of knowledge of the molecular mechanisms leading to PDN. In our current study, we use an animal model of type 2 diabetes in order to understand the roles of p38 in PDN. Previously, we have demonstrated that the C57BLK db/db (db/db) mouse, a model of type 2 diabetes that carries the loss-of-function leptin receptor mutant, develops mechanical allodynia in the hind paws during the early stage (6-12 wk of age) of diabetes. Using this timeline of PDN, we can investigate the signaling mechanisms underlying mechanical allodynia in the db/db mouse. Results We studied the role of p38 in lumbar dorsal root ganglia (LDRG) during the development of mechanical allodynia in db/db mice. p38 phosphorylation was detected by immunoblots at the early stage of mechanical allodynia in LDRG of diabetic mice. Phosphorylated p38 (pp38) immunoreactivity was detected mostly in the small- to medium-sized LDRG neurons during the time period of mechanical allodynia. Treatment with an antibody against nerve growth factor (NGF) significantly inhibited p38 phosphorylation in LDRG of diabetic mice. In addition, we detected higher levels of inflammatory mediators, including cyclooxygenase (COX) 2, inducible nitric oxide synthases (iNOS), and tumor necrosis factor (TNF)-α in LDRG neurons of db/db mice compared to non-diabetic db+ mice. Intrathecal delivery of SB203580, a p38 inhibitor, significantly inhibited the development of mechanical allodynia and the upregulation of COX2, iNOS and TNF-α. Conclusions Our findings suggest that NGF activated-p38 phosphorylation mediates mechanical allodynia in the db/db mouse by upregulation of multiple inflammatory mediators in LDRG.

Abstract Background Integrins are required for normal muscle differentiation and disruptions in integrin signaling result in human muscle disease. The intracellular components that regulate integrin function during myogenesis are poorly understood. Unc-112 is an integrin-associated protein required for muscle development in C. elegans. To better understand the intracellular effectors of integrin signaling in muscle, we examined the mammalian homolog of Unc-112, kindlin-2. Results Kindlin-2 expression is upregulated during differentiation and highly enriched at sites of integrin localization. RNAi knockdown of kindlin-2 in C2C12 cells results in significant abnormalities during the early stages of myogenesis. Specifically, differentiating myocytes lacking kindlin-2 are unable to elongate and fail to fuse into multinucleated myotubes. These changes are correlated with decreased cell substratum adhesion and increased cell motility. They are also associated with redistribution of a known kindlin-2 binding partner, integrin linked kinase (ILK), to the membrane insoluble subcellular fraction. Conclusion In all, our study reveals kindlin-2 as a novel integrin adaptor protein important for muscle differentiation, and identifies it particularly as a critical regulator of myocyte elongation.

Properties of the organic semiconductors can be finely tuned via changes in their molecular structure. However, the relationship between the molecular structure, molecular packing, and (opto)electronic properties of the organic semiconductors to guide their smart design remains elusive. In this study, we address computationally and experimentally the impact of subtle modification of a thiophene-phenylene co-oligomer CF 3 -PTTP-CF 3 on the molecular properties, crystal structure, charge transport, and optoelectronic properties. This modification consists in the substitution of two C-H atom pairs by N atoms in the thiophene units and hence converting them to thiazole units. A dramatic effect of the N-substitution on the crystal structure-the crossover from the herringbone packing motif to π-stacking-is attributed to significant changes in the molecular electrostatic potential. The changes in the molecular and crystal structure resulting from the N-substitution clearly reveal themselves in the Raman spectra. The increase of the calculated electron mobility in the corresponding crystals as a result of the N-substitution is rationalized in terms of the changes in the molecular and crystal structure. The charge transport, electroluminescence, and photoelectric properties are compared in thin-film organic field-effect transistors based on CF 3 -PTTP-CF 3 and its N-substituted counterpart. An intriguing similarity between the effects of N-substitution in the thiophene rings and fluorination of the thiophene-phenylene oligomer is revealed, which is probably associated with a more general effect of electronegative substitution. The obtained results are anticipated to facilitate the rational design of organic semiconductors., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Owing to the combination of efficient charge transport and bright luminescence, thiophene-phenylene co-oligomers (TPCOs) are promising materials for organic light-emitting devices such as diodes, transistors and lasers. The synthetic flexibility of TPCOs enables facile tuning of their properties. In this study, we address the effect of various electron-donating and electron-withdrawing symmetric terminal substituents (fluorine, methyl, trifluoromethyl, methoxy, tert-butyl, and trimethylsilyl) on frontier orbitals, charge distribution, static polarizabilities, molecular vibrations, bandgaps and photoluminescence quantum yields of 5,5'-diphenyl-2,2'-bithiophene (PTTP). By combining DFT calculations with cyclic voltammetry and absorption, photoluminescence, and Raman spectroscopies, we show that symmetric terminal substitution tunes the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energies of TPCOs within a range of ∼0.7 eV, shifts the frequencies of the vibrational modes associated with the phenyl rings, changes the photoluminescence quantum yield by about two-fold and slightly changes the bandgap by ∼0.1 eV. We demonstrate that these effects are governed by two factors: the Hammet constant of the substituents and their involvement in the π-conjugation/hyperconjugation described by the effective conjugation length of the substituted oligomer. A detailed picture underlying the effect of the terminal substituents on the electronic, vibrational and optical properties of TPCOs is presented. Overall, the unraveled relationships between the structure and the properties of the substituted PTTPs should facilitate a rational design of π-conjugated (co-)oligomers for efficient organic optoelectronic devices.

Organic electronics requires materials with high charge mobility. Despite decades of intensive research, charge transport in high-mobility organic semiconductors has not been well understood. In this Letter, we address the physical mechanism underlying the exceptionally high band-like electron mobility in F 2 -TCNQ (2,5-difluoro-7,7,8,8-tetracyanoquinodimethane) single crystals among a crystal family of similar compounds F n -TCNQ (n = 0, 2, 4) using a combined experimental and theoretical approach. While electron transfer integrals and reorganization energies did not show outstanding features for F 2 -TCNQ, Raman spectroscopy and solid-state DFT indicated that the frequency of the lowest vibrational mode is nearly twice higher in the F 2 -TCNQ crystal than in TCNQ and F 4 -TCNQ. This phenomenon is explained by the specific packing motif of F 2 -TCNQ with only one molecule per primitive cell so that electron-phonon interaction decreases and the electron mobility increases. We anticipate that our findings will encourage investigators for the search and design of organic semiconductors with one molecule per primitive cell and/or the poor low-frequency vibrational spectrum.

The global eradication of poliomyelitis will require substantial changes in immunization practices. One of the proposed scenarios includes cessation of vaccination with live oral poliovirus vaccine (OPV) and the creation of an OPV stockpile for emergency response in case of the reintroduction of poliovirus into circulation. We describe here a retrospective analysis of the cessation of OPV usage in a region of the Byelorussian Republic of the former Soviet Union in 1963 to 1966. During this period, a widespread circulation and evolution of independent lineages of vaccine-derived polioviruses took place in the region. Some of these lineages appeared to originate from OPV given to 40 children in the community during this period of essentially no vaccinations. The data demonstrate very high risks associated with both the local cessation of OPV vaccination and the proposed use of OPV to control a possible reemergence of poliovirus in the postvaccination period. The high transmissibility of OPV-derived viruses in nonimmune population, documented here, and the known existence of long-term OPV excretors should be also considered in assessing risks of the synchronized global cessation of OPV usage.

According to the WHO global polio eradication initiative acute flaccid paralysis (AFP) surveillance has been conducted in Belarus since 1996. For the period 1996-2002, 295AFP cases were reported. The main indices ofAFP surveillance in Belarus met the WHO criteria. A11 AFP cases, with the exception of one, were virologically examined. Polioviruses (PV) were isolated from 28 (9.5%) of them. Results of intratypic differentiation (a neutralization test with type-specific monoclonal antibodies and a restriction fragment length polymorphism assay) proved vaccine origin of all isolated PV. According to the final classification, 11 AFP cases were classified as vaccine-associated paralytic poliomyelitis (VAPP). Nine VAPP cases were recipient [six of them developed after the first, two--after the third and one--after the fourth oral poliovirus vaccine (OPV) dose] and two cases in non-vaccinated children were classified as contact VAPP cases. PV of all three serotypes were isolated with an equal frequency from the recipient cases and only PV2--from contact ones. Immunological investigations of children with VAPP showed that the majority of them had disorders in B-cell immunity. A risk of one VAPP case per 96,000 first OPV doses and per 745,000 distributed ones was estimated. The other 284 AFP cases were classified as AFP of non-polio etiology (non-polio AFP). Among them Guillain-Barré syndrome (118 cases, 41.5% of all non-polio AFP cases), traumatic neuritis (63 cases, 22.2%), transient monoparesis of limb (35 cases, 12.3%), myelitis (26 cases, 9.2%) were registered most frequently. Vaccine PV were isolated from 19 (6.7%) children with non-polio AFP, 28 (9.9%) children excreted non-polio enteric viruses. In contrast to VAPP, other AFP with PV isolation had no clinical picture typical of poliomyelitis, and had no any residual paralysis 60 days after the onset of paralysis. PV isolation from them seemed to be not related to the etiology of the disease, but was a mere coincidence of paralysis with the recent vaccination. Results of AFP surveillance supported the previous data on the absence of classical poliomyelitis cases caused by wild PV in Belarus for more than 35 years.

Two new enteroviruses (EV) inhibitors with the selective group-specific effect were detected and studied representing the products of the original chemical synthesis. One of them--nifan (arylfuran derivative) inhibits poliomyelitis virus replication, the other one--belvtazide (synchonic acid derivative) blocks non-poliomyelitis EV (ECHO and Coxsackie B) replication. The study of the reference strains of poliomyelitis virus type 1-3, twenty-three ECHO virus types (from the 1st to the 33rd), Coxsackie B virus type 1-6 and 288 primary EV isolates did not reveal type or strain specific variability in the inhibitors effect. Nifan and belvtazide supress the replication of both EV monostrains and their mixtures. The isolates of mixed nature are inhibited by the mixture nifan + belvtazide. At the same time neither separate chemicals nor their blend affects viruses from other families (Adenoviridae, Orthomyxoviridae, Herpesviridae etc.). The mechanism of nifan and belvtazide action is intracellular EV replication inhibition (they do not affect the process of virus adsorption and penetration into the cell), suppression of de novo virus synthesis by 7.0-2.25 lg (tissue culture infective dose 50 per cent) TCID50/ml and of virus-induced RNA synthesis. The drugs feature is high selectivity (90-91%) regarding RNA polioviruses (nifan) and RNA non-poliomyelitis EV (belvtazide). Nifan and belvtazide antiviral effect selectivity allows unknown cytopathic agents (CPA) belonging to the EV to be established with the high degree (over 98%) of reproducibility at the stage of primary identification with the differentiation of poliomyelitis and non-poliomyelitis viruses.

In the Republic of Belarus, immunization of children against measles and mumps had been carried out using monovalent preparations according to the national schedule of measles vaccination at 12 months of age and mumps vaccination at 24 months of age. A rise of rubella incidence in the last few years (i.e., for the official registration period 1980 to 1998, there was an increase from 72.2 to 607.5 cases per 100,000 population) made it necessary to implement immunization against this infection, as well. Therefore, in 1996, combined vaccination against measles, mumps, and rubella of 12-month-old children was carried out for the first time in a clinical trial that used the vaccine Trimovax [Aventis Pasteur (formerly, Pasteur Mérieux Connaught), Lyon, France]. The reactogenicity of the vaccine was investigated in 372 children. Post-vaccination reactions were noted in 5.6% of children; in 1.3% of children the reactions were classified as severe [i.e. associated with body (axillary) temperature > or = 38.6 degrees C]. For the evaluation of immunogenicity, sera from 324 children were obtained 2 to 2.5 months after inoculation, and serum antibody levels were measured by enzyme immunoassays. Among the vaccines, protective antibody titers (expressed in inverse of dilution units) were observed to measles (> or = 1:50) in 97.8%, to mumps (> or = 1:50) in 93.8%, and to rubella (> or = 1:100) in 96.0% of children. Antibodies to all three components of the vaccine were mainly present in intermediate (1:200-1:800) or high (> or = 1:1600) titers: to measles in 96.3%; to mumps in 75.8%; and to rubella in 73.5% of vaccines. The results of these trials are evidence of the good safety and immunogenicity of this MMR vaccine, which provides an alternative to the currently used measles and mumps monovaccines, with the additional benefit of providing immunity against rubella, as well.