Amplification of Fluctuations in Unstable Systems with Disorder

We study the early-stage kinetics of thermodynamically unstable systems with quenched disorder. We show analytically that the growth of initial fluctuations is amplified by the presence of disorder. This is confirmed by numerical simulations of morphological phase separation (MPS) in thin liquid films and spinodal decomposition (SD) in binary mixtures. We also discuss the experimental implications of our results.Comment: 15 pages, 4 figure

Cassia occidentalis poisoning as the probable cause of hepatomyoencephalopathy in children in western Uttar Pradesh

Background & objectives: Recurrent annual outbreaks of acute encephalopathy illness affecting young children have been reported for several years in many districts of western Uttar Pradesh (UP). Our earlier investigations over three consecutive years (2002-2005) proved that these outbreaks were due to a fatal multi-system disease (hepatomyoencephalopathy syndrome) probably caused by some phytotoxin and not due to viral encephalitis as believed so far. We conducted a case-control study to investigate the risk, if any, from various environmental factors and also to identify the putative toxic plant responsible for development of this syndrome. Methods: Eighteen cases with acute hepatomyoencephalopathy syndrome admitted in 2005 in a secondary care paediatric hospital of Bijnor district of western UP were included in the study. Three age-matched controls were selected for each case. A semi-structured questionnaire was developed and applied to all 18 cases and 54 controls. All interviews were conducted within one week of discharge or death of each case. Quantitative data were analyzed using the relevant established statistical tests. Results: Parents of 8 (44.4%) cases gave a definite history of their children eating beans of Cassia occidentalis weed before falling ill, compared with 3 (5.6% controls), the odds ratio being 12.9 (95% CI 2.6-88.8, P<0.001). History of pica was the other associated factor with the disease, odds ratio 5.20 (95% CI 1.4-19.5, P<0.01). No other factor was found significantly associated with the disease. Interpretation & conclusions: Consumption of C. occidentalis beans probably caused these outbreaks, described earlier as hepatomyoencephalopathy syndrome. Public education has the potential to prevent future outbreaks

Genetic Variation in Toll-Like Receptors (TLRs) 2, 4, and 9 Influences HIV Disease Progression Toward Active TB and AIDS

Gaurav Kaushik,1,2 Richa Vashishtha,2 Chaitenya Verma,3 Shipra Sharma,4 Vinay Kumar5 1School of Allied Health Sciences, Sharda University, Greater Noida, Uttar Pradesh, 201310, India; 2Department of Medicine, All India Institute of Medical Sciences, New Delhi, 110029, India; 3Department of Pathology, Wexner Medical Center, Ohio State University, Columbus, OH, USA; 4Shri Guru Ram Rai Institute of Medical & Health Sciences, Dehradun, Uttarakhand, 248001, India; 5Pennsylvania State University Hershey Medical Center, 500 University Dr, Hershey, PA, 17033, USACorrespondence: Gaurav Kaushik; Vinay Kumar, Email [email protected]; [email protected]: Toll-like receptors (TLRs) are identified as one of the key components of the innate immune system. The objective of this study was to explore the influence of genetic variability in these TLRs on human immunodeficiency virus (HIV) disease progression with and without tuberculosis (TB) co-infection.Materials and Methods: This prospective, cross-sectional, and longitudinal study included 373 HIV-positive patients without TB infection. This study aimed to examine the genetic variation in TLRs (TLR2, TLR4, and TLR9) between patients with HIV-1 infection and those who progressed to active TB during the two years of follow-up.Results: During the two year follow-up of 373 positive patients, 98 patients progressed to active TB/AIDS (acquired immunodeficiency syndrome). When comparing 98 HIV patients who developed active TB/AIDS to 275 HIV patients who did not, it was discovered that the frequency of the A allele in TLR9 was considerably higher (p < 0.001) in HIV patients progressed to active TB/AIDS. Ninety eight HIV individuals who advanced to active TB/AIDS showed a significantly higher frequency of the AA genotype in TLR9 than did in HIV patients who had no TB/AIDS (p < 0.001).Conclusion: The increased association of the AA genotype of TLR9 in HIV patients who progressed to active TB during follow-up suggests that HIV-positive patients with the AA genotype of TLR9 have increased susceptibility towards TB during the disease progression.Keywords: toll-like receptors, human immunodeficiency virus, tuberculosis, acquired immunodeficiency syndrome, immune syste

Elucidation of the structural and optical properties of metal cation (Na+, K+, and Bi3+) incorporated Cs2AgInCl6 double perovskite nanocrystals

This study presents series of direct band gap Pb-free double perovskite Cs2AgInxBi1−xCl6, Cs2NaxAg1−xInCl6:Bi and Cs2KxAg1−xInCl6:Bi nanocrystal systems [Cs2B′(I)B′′(III)Cl6] synthesised using a colloidal hot-injection route. The structural properties investigated using powder XRD, TEM, solid state NMR and materials modelling approaches demonstrate that the incorporation of K+ cations into the double perovskite nanocrystal structure occurs simultaneously on both the Cs (A) site and Ag (B′(I)) positions within a series of closely related cubic and monoclinic structures. As a result of defect passivation, significant improvements in the photoluminescence quantum yield (PLQY) of ∼4.7× and ∼1.8× are exhibited in comparison to the Cs2AgInxBi1−xCl6, and Cs2NaxAg1−xInCl6:Bi nanocrystal systems, respectively. Materials modelling using the Ab Initio Random Structure Search (AIRSS) method, and the GIPAW DFT calculation of the NMR parameters from the derived structural realisations, shows that K+ incorporation induces significant short-range structural disorder and multi-phase formation. This is highlighted by the large 133Cs and 39K chemical shift dispersion characterising the MAS NMR data. Density of States (DoS) calculations describing these AIRSS generated structures suggest that increasing ionic character and reduced structural rigidity are strongly correlated with A site substitution of the K+ cation into these cubic and monoclinic phases. The 39K MAS NMR data reveals that the increasing PLQY performance maps directly with the K+ incorporation into the cubic CsKyAg1−yInCl6 phase supporting B site occupancy which is observed to be maximized at a 60 ml% K+ incorporation level. However, additional evidence indicates that low level K+ substitution primarily targets A site occupancy in a surface passivation role. The improvement to the optical properties induced by K+ and Na+ incorporation is rationalised in terms of increased covalent character and structural rigidity associated with decreased Cs+, Na+ and K+ cation mobility, as evidenced by the large (∼2 orders of magnitude) variation in the 133Cs T1 data across each compositional range

A Therapeutic Antibody against West Nile Virus Neutralizes Infection by Blocking Fusion within Endosomes

Defining the precise cellular mechanisms of neutralization by potently inhibitory antibodies is important for understanding how the immune system successfully limits viral infections. We recently described a potently inhibitory monoclonal antibody (MAb E16) against the envelope (E) protein of West Nile virus (WNV) that neutralizes infection even after virus has spread to the central nervous system. Herein, we define its mechanism of inhibition. E16 blocks infection primarily at a post-attachment step as antibody-opsonized WNV enters permissive cells but cannot escape from endocytic compartments. These cellular experiments suggest that E16 blocks the acid-catalyzed fusion step that is required for nucleocapsid entry into the cytoplasm. Indeed, E16 directly inhibits fusion of WNV with liposomes. Additionally, low-pH exposure of E16–WNV complexes in the absence of target membranes did not fully inactivate infectious virus, further suggesting that E16 prevents a structural transition required for fusion. Thus, a strongly neutralizing anti–WNV MAb with therapeutic potential is potently inhibitory because it blocks viral fusion and thereby promotes clearance by delivering virus to the lysosome for destruction

The Role of Research in Viral Disease Eradication and Elimination Programs: Lessons for Malaria Eradication

Using their experiences from, and analysis of, global campaigns to eradicate smallpox, poliomyelitis, and measles, Myron Levine and colleagues derive lessons for malaria eradication

Transcription, Epigenetics and Ameliorative Strategies in Huntington’s Disease: a Genome-Wide Perspective

ease (HD) is an early event that shapes the brain transcriptome by both the depletion and ectopic activation of gene products that eventually affect survival and neuronal functions. Disrup-tion in the activity of gene expression regulators, such as transcription factors, chromatin-remodeling proteins, and non-coding RNAs, accounts for the expression changes observed in multiple animal and cellular models of HD and in samples from patients. Here, I review the recent advances in the study of HD transcriptional dysregulation and its causes to finally discuss the possible implications in ameliorative strategies from a genome-wide perspective. To date, the use of genome-wide approaches, predominantly based on microar-ray platforms, has been successful in providing an extensive catalog of differentially regulated genes, including biomarkers aimed at monitoring the progress of the pathology. Although still incipient, the introduction of combined next-generation sequencing techniques is enhancing our comprehension of the mechanisms underlying altered transcriptional dysregulation in HD by providing the first genomic landscapes associated with epigenetics and the occupancy of transcription factors. In addition, the use of genome-wide approaches is becoming more and more necessary to evaluate the efficacy and safety of ameliorative strategies and to identify novel mechanisms of amelioration that may help in the improvement of current preclinical therapeutics. Finally, the major conclusions obtain-ed from HD transcriptomics studies have the potential to be extrapolated to other neurodegenerative disorders