Proton and molecular permeation through the basal plane of monolayer graphene oxide.

Two-dimensional (2D) materials offer a prospect of membranes that combine negligible gas permeability with high proton conductivity and could outperform the existing proton exchange membranes used in various applications including fuel cells. Graphene oxide (GO), a well-known 2D material, facilitates rapid proton transport along its basal plane but proton conductivity across it remains unknown. It is also often presumed that individual GO monolayers contain a large density of nanoscale pinholes that lead to considerable gas leakage across the GO basal plane. Here we show that relatively large, micrometer-scale areas of monolayer GO are impermeable to gases, including helium, while exhibiting proton conductivity through the basal plane which is nearly two orders of magnitude higher than that of graphene. These findings provide insights into the key properties of GO and demonstrate that chemical functionalization of 2D crystals can be utilized to enhance their proton transparency without compromising gas impermeability.

'The Violet Killer'-Successful Treatment of an Infant with Chromobacterium violaceum Sepsis.

Chromobacterium violaceum, a facultative anaerobic proteobacterium, is isolated from water and soil in tropical areas and has been implicated in infections like septicemia, visceral abscesses, skin and soft tissue infections, meningitis and diarrhea. Chromobacterium violaceum sepsis, a rarely reported phenomenon has a very high mortality rate. Here, we report a unique case of Chromobacterium sepsis in an infant. A 48-day-old baby boy was referred to our institution with h/o fever, loose stools and reduced activity. He was intubated and referred to us in septic shock. Radiological investigations revealed multiple abscesses in the liver, spleen and kidneys. The infant was successfully treated with trimethoprim-sulfamethoxazole and ciprofloxacin.

Cellular Fitness Phenotypes of Cancer Target Genes from Oncobiology to Cancer Therapeutics.

To define the growing significance of cellular targets and/or effectors of cancer drugs, we examined the fitness dependency of cellular targets and effectors of cancer drug targets across human cancer cells from 19 cancer types. We observed that the deletion of 35 out of 47 cellular effectors and/or targets of oncology drugs did not result in the expected loss of cell fitness in appropriate cancer types for which drugs targeting or utilizing these molecules for their actions were approved. Additionally, our analysis recognized 43 cellular molecules as fitness genes in several cancer types in which these drugs were not approved, and thus, providing clues for repurposing certain approved oncology drugs in such cancer types. For example, we found a widespread upregulation and fitness dependency of several components of the mevalonate and purine biosynthesis pathways (currently targeted by bisphosphonates, statins, and pemetrexed in certain cancers) and an association between the overexpression of these molecules and reduction in the overall survival duration of patients with breast and other hard-to-treat cancers, for which such drugs are not approved. In brief, the present analysis raised cautions about off-target and undesirable effects of certain oncology drugs in a subset of cancers where the intended cellular effectors of drug might not be good fitness genes and that this study offers a potential rationale for repurposing certain approved oncology drugs for targeted therapeutics in additional cancer types.

L-DOPA synthesis in Mucuna pruriens (L.) DC. is regulated by polyphenol oxidase and not CYP 450/tyrosine hydroxylase: An analysis of metabolic pathway using biochemical and molecular markers.

Mucuna pruriens L., commonly known as velvetbean or cow-itch, is a self-pollinated tropical legume of the family Fabaceae, known for its medicinal properties. The active principle L-DOPA extracted from the plant is a potent drug used in the treatment of Parkinson's disease. Although, it is hypothesized that a single step reaction can produce L-DOPA, the presence of optional routes makes the pathway more intricate. For instance, the catecholamine biosynthetic pathway, which leads to L-DOPA production, could occur by hydroxylation of tyrosine to L-DOPA either by polyphenol oxidase (PPO) or tyrosine hydroxylase (TH). Furthermore, Cytochrome P450 (CYP) enzymes can also cause hydroxylation of tyrosine, resulting in L-DOPA synthesis. Therefore, the present investigation was focused on validating the step, which catalyzes the synthesis of L-DOPA, at the biochemical and molecular levels. Enzyme inhibitor studies showed significant inhibition of PPO enzyme with corresponding decrease in L-DOPA synthesis while TH and CYP inhibition had no effect on L-DOPA synthesis. Activity staining of non-denaturing PAGE gel for PPO and TH showed activity only to PPO enzyme. Following in-gel assay and tryptic digestion of the excised stained gel portion, peptide recovery and LC-MS/MS analysis were performed. Degenerate primers based on peptide sequence resulted in an 800bp amplicon. The subsequent sub-cloning, RACE analysis and BLAST search resulted in the isolation of full-length PPO coding sequence of 1800 bp. Structure prediction and phylogenetic analysis of the obtained sequence revealed strong similarity to other plant PPO's like Glycine max, Vigna radiata and Vicia faba of the same family.

Cation-controlled wetting properties of vermiculite membranes and its promise for fouling resistant oil-water separation.

Manipulating the surface energy, and thereby the wetting properties of solids, has promise for various physical, chemical, biological and industrial processes. Typically, this is achieved by either chemical modification or by controlling the hierarchical structures of surfaces. Here we report a phenomenon whereby the wetting properties of vermiculite laminates are controlled by the hydrated cations on the surface and in the interlamellar space. We find that vermiculite laminates can be tuned from superhydrophilic to hydrophobic simply by exchanging the cations; hydrophilicity decreases with increasing cation hydration free energy, except for lithium. The lithium-exchanged vermiculite laminate is found to provide a superhydrophilic surface due to its anomalous hydrated structure at the vermiculite surface. Building on these findings, we demonstrate the potential application of superhydrophilic lithium exchanged vermiculite as a thin coating layer on microfiltration membranes to resist fouling, and thus, we address a major challenge for oil-water separation technology.

Novel Face-Name Paired Associate Learning and Famous Face Recognition in Mild Cognitive Impairment: A Neuropsychological and Brain Volumetric Study.

PURPOSE: To assess visual associative learning and famous face recognition ability among subjects with stable amnestic mild cognitive impairment (MCI) relative to early stage dementia due to Alzheimer's disease (AD) and cognitively normal healthy controls (NC) and to correlate these differences with volumetric changes on MRI. METHODS: A hospital-based cross-sectional observational study was conducted on 61 participants. The subjects underwent neuropsychological evaluation, including validated newly designed tests for novel face-name paired association learning recall and famous face recognition. MRI volumetry was done on a subset of patients to ascertain the topographical patterns of volume loss. RESULTS: There were significant differences in performance on free recall for face-name paired associate learning in MCI (n = 22) compared to NC (n = 20) (p < 0.001) and MCI compared to AD (n = 19; p < 0.001). Significant differences were also noted in scores on the famous personalities test between MCI and NC (p = 0.007), and MCI and AD (p = 0.032). The free recall component of face-name pair associative learning significantly correlated with left cuneus (p = 0.005; r = 0.833) and right cuneus (p = 0.003; r = 0.861) volume in AD with no significant correlation among MCI and NC cohorts. CONCLUSIONS: Novel and semantically familiar face-name associative recalls are significantly impaired in MCI, and these potentially predate the MRI volumetric changes in MCI. Our findings expand the spectrum of recall deficits in MCI.

Correction to: Role of astrocytic MeCP2 in regulation of CNS myelination by affecting oligodendrocyte and neuronal physiology and axo-glial interactions.

In the typesetting of the original version of this article, the Publisher inadvertently confused the first and last names of the authors, leading to their misrepresentation in PubMed.

Trapping, manipulation, and crystallization of live cells using magnetofluidic tweezers.

Live mammalian cells are captured and manipulated in magnetofluidic traps created in a suspension of biocompatible, magnetic nanoparticles by a coaxial magnetic/non-magnetic "micropen". Upon activation by an external electromagnet, the pen creates microscale gradients of magnetic field and nanoparticle concentration that translate into directional and confining forces acting on the cells. Both individual cells and cell collections can be trapped by this method, allowing, for instance, for the formation of regularly shaped cell assemblies. The method does not entail any local heating artifacts and does not require magnetic tagging of the cells.

Miniature in vivo MEMS-based line-scanned dual-axis confocal microscope for point-of-care pathology.

There is a need for miniature optical-sectioning microscopes to enable in vivo interrogation of tissues as a real-time and noninvasive alternative to gold-standard histopathology. Such devices could have a transformative impact for the early detection of cancer as well as for guiding tumor-resection procedures. Miniature confocal microscopes have been developed by various researchers and corporations to enable optical sectioning of highly scattering tissues, all of which have necessitated various trade-offs in size, speed, depth selectivity, field of view, resolution, image contrast, and sensitivity. In this study, a miniature line-scanned (LS) dual-axis confocal (DAC) microscope, with a 12-mm diameter distal tip, has been developed for clinical point-of-care pathology. The dual-axis architecture has demonstrated an advantage over the conventional single-axis confocal configuration for reducing background noise from out-of-focus and multiply scattered light. The use of line scanning enables fast frame rates (16 frames/sec is demonstrated here, but faster rates are possible), which mitigates motion artifacts of a hand-held device during clinical use. We have developed a method to actively align the illumination and collection beams in a DAC microscope through the use of a pair of rotatable alignment mirrors. Incorporation of a custom objective lens, with a small form factor for in vivo clinical use, enables our device to achieve an optical-sectioning thickness and lateral resolution of 2.0 and 1.1 microns respectively. Validation measurements with reflective targets, as well as in vivo and ex vivo images of tissues, demonstrate the clinical potential of this high-speed optical-sectioning microscopy device.

Macrobrachium indianum (Decapoda: Palaemonidae), a new species of hill stream prawn from Pambar River, Kerala, India.

Macrobrachium indianum new species is described from the Pambar River, Kerala, S. India. The species shares certain characters with M. gurudeve Jayachandran & Raji, 2004, M. bombayense Almelker & Sankolli, 2006 and M. kulkarnii Almelker & Sankolli, 2006, while it differs remarkably from these three species in distinctive diagnostic characters: rostral formula 7-8/3-4 with 1 postorbital teeth, one tooth above orbit; carapace smooth with distal end of rostrum directed downwards; cephalothorax longer than rostrum; in second chelate leg, proximal cutting edge of movable finger with two weak denticles, one weak denticle in immovable finger, carpus longer than merus, merus shorter than propodus and longer than ischium; dactylus the shortest podomere. Five thick and a few thin reddish brown bands of chromatophores are seen on carapace. Pigmentation is found mid and ventro-laterally on abdominal segments, pereiopods have chromatophores at the distal part of podomeres.

Sequence and Bioinformatic Analysis of Family 1 Glycoside Hydrolase (GH) 1 Gene from the Oomycete Pythium myriotylum Drechsler.

The oomycetous phytopathogen Pythium myriotylum secretes cellulases for growth/nutrition of the necrotroph. Cellulases are multi-enzyme system classified into different glycoside hydrolase (GH) families. The present study deals with identification and characterization of GH gene sequence from P. myriotylum by a PCR strategy using consensus primers. Cloning of the full-length gene sequence using genome walker strategy resulted in identification of 1230-bp P. myriotylum GH gene sequence, designated as PmGH1. Analysis revealed that PmGH1 encodes a predicted cytoplasmic 421 amino acid protein with an apparent molecular weight of 46.77 kDa and a theoretical pI of 8.11. Tertiary structure of the deduced amino acid sequence showed typical (α/ß)8 barrel folding of family 1 GHs. Sequence characterization of PmGH1 identified the conserved active site residues, viz., Glu 181 and Glu 399, that function as acid-base catalyst and catalytically active nucleophile, respectively. Binding sites for N-acetyl-D-glucosamine (NAG) were revealed in the PmGH1 3D structure with Glu181 and Glu399 positioned on either side to form a catalytic pair. Phylogenetic analysis indicated a closer affiliation of PmGH1 with sequences of GH1 family. Results presented are first attempts providing novel insights into the evolutionary and functional perspectives of the identified P. myriotylum GH.

Antimicrobial sensitivity pattern of bacterial pathogens in urinary tract infections in South Delhi, India.

Seventy-four bacterial proven cases of urinary tract infections were studied, and identified by Mac Conkey agar and blood agar medium separately; all the isolates were subjected to antimicrobial sensitivity testing by Stokes technique. Ninty-six percent of total isolated organisms were found to be gram negative while remaining 4% were gram positive. Among gram negatives, E. coli and gram positive S. aureus were the most prevalent organisms. The percentage of gram negative isolates were as follows, E. coli (79.7%) followed by Klebsiella (9.5%), Pseudomonas, Acinetobacter were (2.7% each), Proteus constituted (1.4%). and among gram positive S. aureus (4%). The antibiotic resistance of identified organisms was carried out by disc-diffusion method with commercially available disc of thirteen antibiotics having different mode of actions such as inhibition of cell wall synthesis, membrane permeability alternatives, inhibition of protein synthesis and DNA synthesis inhibitors. Gram negatives showed more resistance to these antibiotics as compared to gram positive organisms. The most effective antibiotic for gram negative UTI isolates is amikacin showing 63% efficacy followed by Cefotaxime 55% efficacy, Amoxicillin and Ciprofloxacin with (49% each) efficacy. Among gram positives, Chloramphenicol, Co-trimoxazole, Gentamicin, Amikacin, Ciprofloxacin and Cefotaxime are most effective with (66.6% each) efficacy, then Ampicillin, Amoxicillin, Tetracycline and norfloxacin with (33.3% each) efficacy.

Corosolic acid content and SSR markers in Lagerstroemia speciosa (L.) Pers.: a comparative analysis among populations across the Southern Western Ghats of India.

Lagerstroemia speciosa commonly known as 'Banaba' is native of south-east Asia which exhibits both horticultural and therapeutic value. The anti-diabetic and anti-obese property of the tree is attributed to corosolic acid (CRA)-a pentacyclic triterpene seen predominantly in the mature leaves. Although there are studies on either chemical or genetic variation in L. speciosa from different regions, none have dealt with their association to discuss the formation of chemical diversity. For the first time, we have analyzed CRA content in 12 natural populations corresponding to 42 samples seen in the Southern Western Ghats (SWG) using chromatography techniques and genetic variation estimated using SSR markers. Significant variation in percentage distribution of CRA ranging from 0.005% to 0.868% dr.wt. was recorded wherein populations from the north SWG contain relatively more active principle (mean=0.321%) than their counterparts in the south (mean=0.064%). Similarly, SSR data showing relatively high rate of gene flow (Nm=2.72) and low genetic differentiation (FST=0.14) is indicative that populations from north are genetically more diverse than those in the south (Nm=0.48; FST=0.38). The scatter plot derived by Principle Component Analysis (PCA) of chemical and genetic data shows similar pattern of clustering that reveals strong association between the two sets of data. It is concluded that the observed variation in CRA content in natural populations of the species depends more on the genetic background and less on edaphic factors.

Description, DNA barcode and phylogeny of a new species, Macrobrachium abrahami (Decapoda: Palaemonidae) from Kerala, India.

Macrobrachium abrahami, new species is described from Vamanapuram River, Kerala, South India. DNA bar-coding using Cytochrome B gene sequences has elucidated the taxonomic status of the new species and the ML tree reveals that M. abrahami sp. nov., is phylogenetically close to M. prabhakarani, but morphologically more similar to M. scabriculum. However, the species shares certain morphological characters with M. scabriculum, M. prabhakarani and M. lanatum, but differs remarkably from these three species in distinctive diagnostic characters: rostrum moderately long, convex, distal end directed upwards, rostral formula 12-15/2-3 with 5-6 postorbital teeth, and carapace glabrous. In larger second chelate leg, fingers stout, pubescence restricted to their base; proximal half of cutting edge with fifteen denticles. In smaller second chelate leg, cutting edge of both fingers carry six small denticles situated proximally, distal one comparatively larger. Delicate setae are seen throughout the palm. A row of dark chromatophores is present along the posterio-dorsal margin of uropodal exopods and endopods, close to the base of uropodal setae. The thickness of each band of the row is almost equal to the thickness of uropodal setae.

Cefotaximase and AmpC-producing Shigella flexneri in case of dysentery from southern India.

Diarrhoea and dysentery caused by Shigella spp. are major public health concerns. Emerging multidrug resistance (MDR) in this pathogen further complicates this disease. Extended spectrum ß-lactamases (ESBLs) have been described in this pathogen, which significantly compromises the treatment options for shigellosis. The usual ESBLs seen are sulfhydryl variable (SHV)-type; cefotaximases (CTX-M) are very uncommonly detected. Here, we report a CTX-M type and AmpC-producing Shigella flexneri from a three-year-old boy residing in Central Kerala, South India.

Age-specific vaccine effectiveness of seasonal 2010/2011 and pandemic influenza A(H1N1) 2009 vaccines in preventing influenza in the United Kingdom.

An analysis was undertaken to measure age-specific vaccine effectiveness (VE) of 2010/11 trivalent seasonal influenza vaccine (TIV) and monovalent 2009 pandemic influenza vaccine (PIV) administered in 2009/2010. The test-negative case-control study design was employed based on patients consulting primary care. Overall TIV effectiveness, adjusted for age and month, against confirmed influenza A(H1N1)pdm 2009 infection was 56% (95% CI 42-66); age-specific adjusted VE was 87% (95% CI 45-97) in <5-year-olds and 84% (95% CI 27-97) in 5- to 14-year-olds. Adjusted VE for PIV was only 28% (95% CI -6 to 51) overall and 72% (95% CI 15-91) in <5-year-olds. For confirmed influenza B infection, TIV effectiveness was 57% (95% CI 42-68) and in 5- to 14-year-olds 75% (95% CI 32-91). TIV provided moderate protection against the main circulating strains in 2010/2011, with higher protection in children. PIV administered during the previous season provided residual protection after 1 year, particularly in the <5 years age group.

Description of a new subspecies, Macrobrachium aemulum madhusoodani (Decapoda: Palaemonidae) from Neyyar River, Kerala, S. India.

Macrobrachium aemulum madhusoodani, a new subspecies of M. aemulum (Nobili, 1906) is described and illustrated. The distinctive characters of the subspecies are: rostral formula 9-13/2, second pereiopods dissimilar in shape and unequal in size, movable finger of larger second pereiopod with 2 large denticles on the proximal part and 6 weak denticles on distal part. Similar pattern of dentition is present on immovable finger also. In second small pereiopod, fingers stout, equal, unarmed with distinct gap in between when closed. Numerous stiff setae present on cutting edges of fingers. Telson extends beyond the level of the outer lateral spine of the uropodal exopod. Some of the distinctive morphometric and meristic characters of the specimens did not conform to that collected and described from New Caledonia by Nobili (1906) and recorded from India by Jayachandran and Joseph (1988). Since the features cannot be reckoned as mere growth variations, it is described herein as a new subspecies.

Morphology and molecular phylogeny of Macrobrachium snpurii, a new species of the genus Macrobrachium Bate, 1868 from Kerala, India.

Macrobrachium snpurii sp. nov., collected from the Karamana River, in the lower reaches of Western Ghats, is described and illustrated. DNA barcoding using Cytochrome B gene sequences has elucidated the taxonomic status of the new species and the NJ tree reveals that M. snpurii sp. nov., is phylogenetically close to M. idella idella. However, morphometric and meristic features of the species share certain characters with M. idella idella, M. patheinense and M. tratense, while it diverges remarkably from these three species in distinctive diagnostic characters: rostral formula 12-14/4 with 2 postorbital teeth; carapace smooth with distal end of rostrum directed upwards; chelae with 2 proximal denticles both in the movable and immovable fingers. A wide gap present in the distal part of the chelae, when fingers are closed. Movable finger, longer than the immovable and distal end of fingers inwardly hook-like; palm more pigmented than fingers and telson extends beyond the level of the outer lateral spine of uropodal exopod. A pair of plumose setae is present between the inner pair of movable spines of telson.

Antimicrobial therapy and outcome of septicemia patients admitted to a University Hospital in Delhi.

Septicemia is a common clinical condition encountered in most of the hospitals in this region of the world. However, limited information is available in the Indian literature on antimicrobial usage in patients with suspected or proven cases of septicemia. The aim of the present study is on the one hand to describe the clinical characteristics of septicemia, the causative pathogens, the current pattern of antimicrobial use, the clinical outcome, the acquisition cost of commonly used antimicrobial regimens and on the other hand to monitor adverse drug reactions (ADRs) during therapy of septicemia patients admitted to a University Hospital in Delhi. We prospectively reviewed the antimicrobial therapy in 34 clinically diagnosed septicemia cases admitted to a University Hospital from July 2009 to December 2009. All study patients presented various clinical signs and symptoms, fever, diarrhoea and vomiting were most commonly reported. Microorganisms could be identified in 13 (38.2%) of the patients. Escherichia coli (41.2%) constituted the most prevalent bacterial pathogen. Among culture positive patients, 15.4% received ceftriaxone as the most common empirical antimicrobial therapy; among culture negative patients, 19% received cefotaxime plus amikacin as the most common empirical antimicrobial therapy. The average acquisition cost of the 1st line antimicrobial regimen was higher in culture positive than in culture negative patients, but it was reversed for the 2nd line therapy. Overall, 67.6% patients were discharged after recovery, 23.5% were transferred out and 8.8% died during the course of therapy. 9 (26.5%) patients experienced ADRs during the antimicrobial therapy. These findings may have an important implication for developing comprehensive, evidence-based guidelines for the practical treatment of septicemia, adherence to which may lead to a more rational antimicrobial therapy, to cost reduction and to an improved level of care of patients with septicemia.