Enzymatic depletion of circulating glutamine is immunosuppressive in cancers

Although glutamine addiction in cancer cells is extensively reported, there is controversy on the impact of glutamine metabolism on the immune cells within the tumor microenvironment (TME). To address the role of extracellular glutamine, we enzymatically depleted circulating glutamine using PEGylated Helicobacter pylori gamma-glutamyl transferase (PEG-GGT) in syngeneic mouse models of breast and colon cancers. PEG-GGT treatment inhibits growth of cancer cells in vitro, but in vivo it increases myeloid-derived suppressor cells (MDSCs) and has no significant impact on tumor growth. By deriving a glutamine depletion signature, we analyze diverse human cancers within the TCGA and illustrate that glutamine depletion is not associated with favorable clinical outcomes and correlates with accumulation of MDSC. Broadly, our results help clarify the integrated impact of glutamine depletion within the TME and advance PEG-GGT as an enzymatic tool for the systemic and selective depletion (no asparaginase activity) of circulating glutamine in live animals.

Smartphone-readable RPA-LFA for the high-sensitivity detection of Leishmania kDNA using nanophosphor reporters

Early diagnosis of infectious diseases improves outcomes by enabling earlier delivery of effective treatment, and helps prevent further transmission by undiagnosed persons. We demonstrated a proof-of-concept assay combining isothermal amplification and lateral flow assay (LFA) for early diagnosis of cutaneous leishmaniasis, a vector-borne infectious disease that affects ca. 700,000 to 1.2 million people annually. Conventional molecular diagnostic techniques based on polymerase chain reaction (PCR) require complex apparatus for temperature cycling. Recombinase polymerase amplification (RPA) is an isothermal DNA amplification method that has shown promise for use in low-resource settings. Combined with lateral flow assay as the readout, RPA-LFA can be used as a point-of-care diagnostic tool with high sensitivity and specificity, but reagent costs can be problematic. In this work, we developed a highly-sensitive smartphone-based RPA-LFA for the detection of Leishmania panamensis DNA using blue-emitting [(Sr0.625Ba0.375)1.96Eu0.01Dy0.03]MgSi2O7 (SBMSO) persistent luminescent nanophosphors as LFA reporters. The greater detectability of nanophosphors allows the use of a reduced volume of RPA reagents, potentially reducing the cost of RPA-LFA. The limit of detection (LOD) of RPA with gold nanoparticle-based LFA readout is estimated at 1 parasite per reaction, but LOD can be 100-fold better, 0.01 parasites per reaction, for LFA based on SBMSO. This approach may be useful for sensitive and cost-effective point-of-care diagnosis and contribute to improved clinical and economic outcomes, especially in resource-limited settings.

Protein A-Nanoluciferase fusion protein for generalized, sensitive detection of immunoglobulin G

Detection and quantification of antibodies, especially immunoglobulin G (IgG), is a cornerstone of ELISAs, many diagnostics, and the development of antibody-based drugs. Current state-of-the-art immunoassay techniques for antibody detection require species-specific secondary antibodies and carefully-controlled bioconjugations. Poor conjugation efficiency degrades assay performance and increases the risk of clinical false positives due to non-specific binding. We developed a generic, highly-sensitive platform for IgG quantification by fusing the IgG-Fc binding Z domain of Staphylococcal Protein A with the ultrabright bioluminescence reporter Nanoluc-luciferase (Nluc). We demonstrated the application of this fusion protein in a sandwich IgG detection immunoassay using surface-bound antigens to capture target IgG and protein A-Nanoluc fusion as the detector. We optimized the platform's sensitivity by incorporating multiple repeats of the Z domain into the fusion protein constructs. Using rabbit and mouse anti-SARS-CoV-2 Nucleoprotein IgGs as model analytes, we performed ELISAs in two different formats, either with SARS-CoV-2 Nucleoprotein as the capture antigen or with polyclonal chicken IgY as the capture antibody. Using standard laboratory equipment, the platform enabled the quantitation of antibody analytes at concentrations as low as 10 pg/mL (67 fM).

Isolation and Barcoding of Trace Pollen-free DNA for Authentication of Honey

Adulteration and mislabeling of honey to mask its true origin have become a global concern. Pollen microscopy, the current gold standard for identifying honey's geographical and plant origins, is laborious, requires extensive training, and fails to identify filtered honey and honey spiked with pollen from a more favorable plant to disguise its origins. We successfully isolated pollen-free DNA from filtered honey using three types of adsorbents: (i) anti-dsDNA antibodies coupled to magnetic microspheres; (ii) anion-exchange adsorbent; and (iii) ceramic hydroxyapatite. The internal transcribed spacer 2 region of the captured pollen-free DNA was polymerase chain reaction-amplified and subjected to next-generation sequencing. Using an in-house bioinformatics pipeline, initial experiments showed that anion exchange had the greatest capacity to capture trace pollen-free DNA, and it was successfully applied to isolate DNA from five honey samples. Enrichment of trace pollen-free DNA from filtered honey samples opens a new approach for identifying the true origins of honey.

Trends in the prevalence of infiltrative cardiomyopathy among patients with in-hospital cardiac arrest – insight from the US national inpatient sample database

Background

Sarcoidosis, amyloidosis, hemochromatosis and scleroderma are the most common systemic disorders leading to infiltrative cardiomyopathy (InCM). Each of them has been associated with conduction abnormalities and sudden cardiac death. In patients who undergo in-hospital cardiac arrest, a high index of suspicion is required to rule out InCM as an underlying contributor.

Purpose

We aimed to analyse the temporal trend in the prevalence of InCM among patients with in-hospital cardiac arrest and identify factors associated with increased mortality in this population.

Methods

We analysed data from the National Inpatient Sample (NIS), which is the largest publicly available database of in-hospital patients in the Unites States. Using ICD-10 coding, we identified patients who were hospitalized across 10 years from 2010–2019. Patients with diagnosis codes for both cardiac arrest and a subtype of InCM were included. Demographic characteristics and co-morbidity data were collected. Statistical analysis was performed using STATA.

Results

The total number of patients with a diagnosis of in-hospital cardiac arrest was 19,34,260. Of these, the total number with InCM was 14,803 (0.77%), which comprised our study population. Mean age was 63 years. The overall prevalence of InCM across the years ranged between 0.75 to 0.9%, with a significant temporal increase (p<0.01). Prevalence of females ranged between 51% to 62% and significantly outnumbered males across the time period. (p=0.011). Incidence of in-hospital mortality ranged between 61% to 76% for females and 30 to 38% for males. Race based analysis showed that prevalence of Caucasians ranged from 51% to 62% while that of African Americans (AA) ranged from 57% to 73%. The incidence of mortality was similar in both populations. Sarcoidosis was the most prevalent form of InCM, accounting for nearly two-fifths of all cases while amyloidosis and scleroderma both accounted for nearly 20% each. Haemochromatosis was present in 10% of the population. Overall mortality rate in our study population was 60.6%. The following co-morbidities were more prevalent in patients with InCM than those without: history of heart failure, chronic obstructive pulmonary disease (COPD), chronic kidney disease, anaemia, malignancy, coagulopathy, ventricular tachycardia, acute kidney injury and stroke. The following factors were independent predictors of in-hospital mortality-age (p=0.001), female gender (p=0.016), Hispanic race (p=0.039), history of COPD (p<0.001) and presence of malignancy (p=0.042).

Conclusion

The prevalence of infiltrative cardiomyopathy in patients with in-hospital cardiac arrest is increasing. Females, older patients and Hispanic population are at an increased risk of mortality. Sex and race based disparities in the prevalence of InCM in patients with in-hospital cardiac arrest is an area of further research.

Funding Acknowledgement

Type of funding sources: None.

Acoustic particle trapping driven by axial primary radiation force in shaped traps

We study particle trapping driven by the axial primary radiation force (A-PRF) in shaped traps exposed to standing bulk acoustic waves (S-BAW) using numerical simulations and experiments. The utilization of the stronger A-PRF as the main retention force is a consequence of standing-wave formation along the flow direction, instead of the orthogonal direction as in the case of traditionally used lateral-PRF S-BAW trapping setups. The study of particle dynamics reveals that the competition between A-PRF and viscous drag force governs particle trajectory. The ratio of the acoustic energy to the viscous work (β) provides a general criterion for particle trapping at a distinctive off-node site that is spatially controllable. Particles get trapped for β≥β_{cr} at some distance away from the nodal plane and the distance varies as β^{-c} (c=0.6-1.0). The use of A-PRF as the retention force could potentially allow traditional S-BAW trapping systems to envisage high-throughput advancements surpassing the current standards in cell-handling unit operations.

Chiral Magnetic Effect of Hot Electrons

We propose a way to observe the chiral magnetic effect in noncentrosymmetric Weyl semimetals under the action of a strong electric field, via the nonlinear part of their I-V characteristic that is odd in the external magnetic field, or odd-in-magnetic field voltages in electrically open circuits. This effect relies on valley-selective heating in such materials, which, in general, leads to nonequilibrium valley population imbalances. In the presence of an external magnetic field, such a valley-imbalanced Weyl semimetal will, in general, develop an electric current along the direction of the magnetic field-the chiral magnetic effect. We also discuss a specific experimental setup to observe the chiral magnetic effect of hot electrons.

Dynamic chiral magnetic effect and anisotropic natural optical activity of tilted Weyl semimetals

We study the dynamic chiral magnetic conductivity (DCMC) and natural optical activity in an inversion-broken tilted Weyl semimetal (WSM). Starting from the Kubo formula, we derive the analytical expressions for the DCMC for two different directions of the incident electromagnetic wave. We show that the angle of rotation of the plane of polarization of the transmitted wave exhibits remarkable anisotropy and is larger along the tilt direction. This striking anisotropy of DCMC results in anisotropic optical activity and rotary power, which can be experimentally observed as a topological magneto-electric effect of inversion-broken tilted WSMs. Finally, using the low energy Hamiltonian, we show that the DCMC follows the universal \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\frac{{\bf{1}}}{{{\boldsymbol{\omega }}}^{{\bf{2}}}}$$\end{document}1ω2 decay in the high frequency regime. In the low frequency regime, however, the DCMC shows sharp peaks at the tilt dependent effective chemical potentials of the left-handed and right-handed Weyl points. This can serve as a signature to distinguish between the type-I and type-II Weyl semimetals.

Berry phase theory of planar Hall effect in topological insulators

The appearance of negative longitudinal magnetoresistance (LMR) in topological semimetals such as Weyl and Dirac semimetals is understood as an effect of chiral anomaly, whereas such an anomaly is not well-defined in topological insulators. Nevertheless, it has been shown recently in both theory and experiments that nontrivial Berry phase effects can give rise to negative LMR in topological insulators even in the absence of chiral anomaly. In this paper, we present a quasi-classical theory of another intriguing phenomenon in topological insulators - also ascribed to chiral anomaly in Weyl and Dirac semimetals- the so-called planar Hall effect (PHE). PHE implies the appearance of a transverse voltage in the plane of applied non-parallel electric and magnetic fields, in a configuration in which the conventional Hall effect vanishes. Starting from Boltzmann transport equations we derive the expressions for PHE and LMR in topological insulators in the bulk conduction limit, and show the important role played by orbital magnetic moment. Our theoretical results for magnetoconductance with non-parallel electric and magnetic fields predict detailed experimental signatures in topological insulators - specifically of planar Hall effect - that can be observed in experiments.

Nature of spiral state and absence of electric polarisation in Sr-doped YBaCuFeO5 revealed by first-principle study

Experimental results on YBaCuFeO5, in its incommensurate magnetic phase, appear to disagree on its ferroelectric response. Ambiguity exists on the nature of the spiral magnetic state too. Using first-principles density functional theory (DFT) calculations for the parent compound within LSDA + U + SO approximation, we reveal the nature of spiral state. The helical spiral is found to be more stable below the transition temperature as spins prefer to lie in ab plane. Dzyaloshinskii-Moriya (DM) interaction turns out to be negligibly small and the spin current mechanism is not valid in the helical spiral state, ruling out an electric polarisation from either. These results are in very good agreement with the recent, high quality, single-crystal data. We also investigate the magnetic transition in YBa1-xSrxCuFeO5 for the entire range (0 ≤ x ≤ 1) of doping. The exchange interactions are estimated as a function of doping and a quantum Monte Carlo (QMC) calculation on an effective spin Hamiltonian shows that the paramagnetic to commensurate phase transition temperature increases with doping till x = 0.5 and decreases beyond. These observations are consistent with experimental findings.

"Electro-Typing" on a Carbon-Nanoparticles-Filled Polymeric Film using Conducting Atomic Force Microscopy

Next-generation electrical nanoimprinting of a polymeric data sheet based on charge trapping phenomena is reported here. Carbon nanoparticles (CNPs) (waste carbon product) are deployed into a polymeric matrix (polyaniline) (PANI) as a charge trapping layer. The data are recorded on the CNPs-filled polyaniline device layer by "electro-typing" under a voltage pulse (V_ET , from ±1 to ±7 V), which is applied to the device layer through a localized charge-injection method. The core idea of this device is to make an electrical image through the charge trapping mechanism, which can be "read" further by the subsequent electrical mapping. The density of stored charges at the carbon-polyaniline layer, near the metal/polymer interface, is found to depend on the voltage amplitude, i.e., the number of injected charge carriers. The relaxation of the stored charges is studied by different probe voltages and for different devices, depending on the percolation of the CNPs into the PANI. The polymeric data sheet retains the recorded data for more than 6 h, which can be refreshed or erased at will. Also, a write-read-erase-read cycle is performed for the smallest "bit" of stored information through a single contact between the probe and the device layer.

Chiral Anomaly as the Origin of the Planar Hall Effect in Weyl Semimetals

In condensed matter physics, the term "chiral anomaly" implies the violation of the separate number conservation laws of Weyl fermions of different chiralities in the presence of parallel electric and magnetic fields. One effect of the chiral anomaly in the recently discovered Dirac and Weyl semimetals is a positive longitudinal magnetoconductance. Here we show that chiral anomaly and nontrivial Berry curvature effects engender another striking effect in Weyl semimetals, the planar Hall effect (PHE). Remarkably, the PHE manifests itself when the applied current, magnetic field, and the induced transverse "Hall" voltage all lie in the same plane, precisely in a configuration in which the conventional Hall effect vanishes. In this work we treat the PHE quasiclassically, and predict specific experimental signatures for type-I and type-II Weyl semimetals that can be directly checked in experiments.

Evaluation of Iron Store by Serum Ferritin in Healthy Blood Donors of Bangladesh

Iron stores in the body exist primarily in the form of ferritin. Small amounts of ferritin secreted into the plasma and plasma ferritin is positively correlated with the size of the total body iron stores. The present study conducted to determine the iron status using the serum ferritin level among healthy Bangladeshi blood donors. The present cross sectional study was conducted in the Department of Transfusion Medicine, Dhaka Medical College, Dhaka, Bangladesh from July 2011 to June 2012. Blood donor signed informed consent and has satisfactory pre-donation health assessment and satisfactory post-donation blood test results were included in the study. Full blood counts were performed within 4 hours of collection using an automated haematology analyzer. Serum ferritin was measured using a validated enzyme immunoassay. Data were analyzed using SPSS version 16 (SPPS Incorporation, Chicago, IL, USA). P value <0.05 was considered as statistically significant. Total 100 blood donors were included in the study, among them 88 were male and 12 were female. Mean±SD of the age of the respondents was 26.8±5.9 years with a range of 19 to 45 years. Mean±SD of heamoglobin level (gm/dl) and total count of Red Blood Cell (million/cmm) were 14.1±1.4 and 5.1±0.4 respectively. Mean±SD of serum ferritin level (ng/ml) was 96.4±69.0ng/ml with a range of 4.1ng/ml to 298.7ng/ml. Among the respondents 9.0% had depleted iron store, 7.0 reduced iron store and 84.0% had normal iron store. Among the respondents 5.0% had iron deficiency anaemia in term of serum ferritin level. Statistically significant difference of serum ferritin level observed between male and female and donors with and without history of previous blood donation. Among the healthy blood donors of Bangladesh abnormal serum ferritin is highly prevalent among blood donors specially among female. Monitoring of iron stores by serum ferritin seems justified in order to identify those with depleted iron stores who will benefit from iron supplementation.

Relationship between Serum Iron Profile and Blood Groups among the Voluntary Blood Donors of Bangladesh

Blood donation results in a substantial iron loss and subsequent mobilization from body stores. Chronic iron deficiency is a well-recognized complication of regular blood donation. The present study conducted to compare the level of serum ferritin, serum iron, total iron binding capacity (TIBC) and percentage transferrin saturation in different ABO and Rhesus type blood groups among the voluntary blood donors of Bangladesh. The present prospective study included 100 healthy voluntary donors attending at Department of Blood Transfusion, Dhaka Medical College, Dhaka between the periods of July 2013 to Jun 2014. From each donor 10mL venous blood sample was taken and divided into heparinized and non-heparinized tubes for determination of hemoglobin (Hb), hematocrit (Hct), serum iron (SI), total iron binding capacity (TIBC) and serum ferritin by standard laboratory methods. Percentage of transferrin saturation (TS) calculated from serum iron and TIBC. Data were analyzed with SPSS (version 16) software and comparisons between groups were made using student's t-test and one way ANOVA. In the present study mean±SD of age of the respondents was 27.2±6.5 years with a range of 18 to 49 years and 81.0% were male and 19.0% were female. Among the donors 18.0% had blood group A, 35.0% had blood group B, 14.0% had blood group AB and 33.0% had blood group O. Among the donors 91.0% had rhesus positive and 9.0% had rhesus negative. Donors with blood group O had lowest haemoglobin, serum iron and transferring saturation levels. Donors with blood group A had highest TIBC level. Donors with blood group B had lowest serum ferritin level. An independent samples 't' test showed statistically significant difference in serum ferritin and percentage transferrin saturation between blood group AB and blood group O and in percentage transferrin saturation between blood group B and blood group O. One way ANOVA showed that there is no significant difference in haemoglobin, serum iron, serum ferritin and percentage transferring saturation in different ABO and Rh blood grouping categories. Blood donors with blood group O had lowest haemoglobin, serum iron and transferring saturation levels and donors with blood group A had highest TIBC level. Blood donors with blood group B had lowest serum ferritin level. The understanding of the different blood groups ability to retain iron in their system can give an insight into their ability to handle the disease iron deficiency anaemia.

Stress Induced Mechano-electrical Writing-Reading of Polymer Film Powered by Contact Electrification Mechanism

Mechano-electrical writing and reading in polyaniline (PANI) thin film are demonstrated via metal-polymer contact electrification mechanism (CEM). An innovative conception for a non-destructive self-powered writable-readable data sheet is presented which can pave the way towards new type of stress induced current harvesting devices. A localized forced deformation of the interface has been enacted by pressing the atomic force microscopic probe against the polymer surface, allowing charge transfer between materials interfaces. The process yields a well-defined charge pattern by transmuting mechanical stress in to readable information. The average of output current increment has been influenced from 0.5 nA to 15 nA for the applied force of 2 nN to 14 nN instead of electrical bias. These results underscore the importance of stress-induced current harvesting mechanism and could be scaled up for charge patterning of polymer surface to writable-readable data sheet. Time evolutional current distribution (TECD) study of the stress-induced patterned PANI surface shows the response of readability of the recorded data with time.

Trends in the genomic epidemiology of Vibrio cholerae O1 isolated worldwide since 1961

Here we describe the international scenario of Vibrio cholerae with a comparative analysis of different aspects of typing. Representative V. cholerae strains (n=108) associated with endemic cholera regions from 29 states of India and worldwide were subjected to microbiological, molecular and phylogenetic study. All of the strains were V. cholerae serogroup O1 biotype El Tor and were typed according to both the new phage (NP) type and Basu & Mukherjee (BM) typing schemes. The predominant phage type was T-27 (NP)/T-4 (BM) (65.7%; n=71), followed by phage type T-27 (NP)/T-2 (BM) (14.8%; n=16), T-26 (NP)/T4 (BM) (12.0%; n=13), T-13 (NP)/T-4 (BM) (2.8%; n=3), T-20 (NP)/T-4 (BM) (1.9%; n=2), T-3 (NP)/T-4 (BM) (0.9%; n=1), T-23 (NP)/T-4 (BM) (0.9%; n=1) and T-24 (NP)/T-2 (BM) (0.9%; n=1). Mismatch amplification mutation assay PCR (MAMA-PCR) findings showed the dominance of ctxB El Tor genotype (77.1%; 54/70) from 1961-1991, whilst the next two epochs showed the supremacy of ctxB classical genotype. Multidrug-resistant strains showed resistance to erythromycin, streptomycin, trimethoprim/sulfamethoxazole, norfloxacin and ampicillin. The regional resistance of epidemic clones in India draws a layout of the rapid dissemination of resistance in the past 30 years and the necessity of proper treatment to protect populations at risk.

Mapping aboveground woody biomass using forest inventory, remote sensing and geostatistical techniques

Mapping forest biomass is fundamental for estimating CO₂ emissions, and planning and monitoring of forests and ecosystem productivity. The present study attempted to map aboveground woody biomass (AGWB) integrating forest inventory, remote sensing and geostatistical techniques, viz., direct radiometric relationships (DRR), k-nearest neighbours (k-NN) and cokriging (CoK) and to evaluate their accuracy. A part of the Timli Forest Range of Kalsi Soil and Water Conservation Division, Uttarakhand, India was selected for the present study. Stratified random sampling was used to collect biophysical data from 36 sample plots of 0.1 ha (31.62 m × 31.62 m) size. Species-specific volumetric equations were used for calculating volume and multiplied by specific gravity to get biomass. Three forest-type density classes, viz. 10-40, 40-70 and >70% of Shorea robusta forest and four non-forest classes were delineated using on-screen visual interpretation of IRS P6 LISS-III data of December 2012. The volume in different strata of forest-type density ranged from 189.84 to 484.36 m(3) ha(-1). The total growing stock of the forest was found to be 2,024,652.88 m(3). The AGWB ranged from 143 to 421 Mgha(-1). Spectral bands and vegetation indices were used as independent variables and biomass as dependent variable for DRR, k-NN and CoK. After validation and comparison, k-NN method of Mahalanobis distance (root mean square error (RMSE) = 42.25 Mgha(-1)) was found to be the best method followed by fuzzy distance and Euclidean distance with RMSE of 44.23 and 45.13 Mgha(-1) respectively. DRR was found to be the least accurate method with RMSE of 67.17 Mgha(-1). The study highlighted the potential of integrating of forest inventory, remote sensing and geostatistical techniques for forest biomass mapping.

Molecular characterization of serologically atypical provisional serovars of Shigella isolates from Kolkata, India

During 2000-2004, 13 Shigella strains that were untypable by commercially available antisera were isolated from children <5 years of age with acute diarrhoea in Kolkata. These strains were subsequently identified as Shigella dysenteriae provisional serovar 204/96 (n = 3), Shigella dysenteriae provisional serovar E23507 (n = 1), Shigella dysenteriae provisional serovar I9809-73 (n = 1), Shigella dysenteriae provisional serovar 93-119 (n = 1), Shigella flexneri provisional serovar 88-893 (n = 6) and Shigella boydii provisional serovar E16553 (n = 1). In this study, characterization of those provisional serovars of Shigella was performed with respect to their antimicrobial resistance, plasmids, virulence genes and PFGE profiles. The drug resistant strains (n = 10) of Shigella identified in this study possessed various antibiotic resistance genetic markers like catA (for chloramphenicol resistance); tetA and tetB (for tetracycline resistance); dfrA1 and sul2 (for co-trimoxazole resistance); aadA1, strA and strB (for streptomycin resistance) and blaOXA-1 (for ampicillin resistance). Class 1 and/or class 2 integrons were present in eight resistant strains. Three study strains were pan-susceptible. A single mutation in the gyrA gene (serine to leucine at codon 83) was present in four quinolone resistant strains. The virulence gene ipaH (invasion plasmid antigen H) was uniformly present in all strains in this study, but the stx (Shiga toxin) and set1 (Shigella enterotoxin 1) genes were absent. Other virulence genes like ial (invasion associated locus) and sen (Shigella enterotoxin 2) were occasionally present. A large plasmid of 212 kb and of incompatibility type IncFIIA was present in the majority of the strains (n = 10) and diversity was noticed in the smaller plasmid profiles of these strains even within the same provisional serovars. PFGE profile analysis showed the presence of multiple unrelated clones among the isolates of provisional Shigella serovars. To the best of our knowledge, this is the first report on the phenotypic and molecular characterization of provisional serovars of Shigella isolates from Kolkata, India.

Growing stock and woody biomass assessment in Asola-Bhatti Wildlife Sanctuary, Delhi, India

Biomass is an important entity to understand the capacity of an ecosystem to sequester and accumulate carbon over time. The present study, done in collaboration with the Delhi Forest Department, focused on the estimation of growing stock and the woody biomass in the so-called lungs of Delhi--the Asola-Bhatti Wildlife Sanctuary in northern Aravalli hills. The satellite-derived vegetation strata were field-inventoried using stratified random sampling procedure. Growing stock was calculated for the individual sample plots using field data and species-specific volume equations. Biomass was estimated from the growing stock and the specific gravity of the wood. Among the four vegetation types, viz. Prosopis juliflora, Anogeissus pendula, forest plantation and the scrub, the P. juliflora was found to be the dominant vegetation in the area, covering 23.43 km(2) of the total area. The study revealed that P. juliflora forest with moderate density had the highest (10.7 m(3)/ha) while A. pendula forest with moderate density had the lowest (3.6 m(3)/ha) mean volume. The mean woody biomass was also found to be maximum in P. juliflora forest with moderate density (10.3 t/ha) and lowest in A. pendula forest with moderate density (3.48 t/ha). The total growing stock was estimated to be 20,772.95 m(3) while total biomass worked out to be 19,366.83 t. A strong correlation was noticed between the normalized difference vegetation index (NDVI) and the growing stock (R(2) = 0.84)/biomass (R(2) = 0.88). The study demonstrated that growing stock and the biomass of the woody vegetation in Asola-Bhatti Wildlife Sanctuary could be estimated with high accuracy using optical remote sensing data.

An in silico structural insights into Plasmodium LytB protein and its inhibition

In most of the pathogenic organisms including Plasmodium falciparum, isoprenoids are synthesized via MEP (MethylErythritol 4-Phosphate) pathway. LytB is the last enzyme of this pathway which catalyzes the conversion of (E)-4-hydroxy-3-methylbut-2-en-1-yl diphosphate (HMBPP) into the two isoprenoid precursors: isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP). Since the MEP pathway is not used by humans, it represents an attractive target for the development of new antimalarial compounds or inhibitors. Here a systematic in-silico study has been conducted to get an insight into the structure of Plasmodium lytB as well as its affinities towards different inhibitors. We used comparative modeling technique to predict the three dimensional (3D) structure of Plasmodium LytB taking E. Coli LytB protein (PDB ID: 3KE8) as template and the model was subsequently refined through molecular dynamics (MD) simulation. A large ligand dataset containing diphospate group was subjected for virtual screening against the target using GOLD 5.2 program. Considering the mode of binding and affinities, 17 leads were selected on basis of binding energies in comparison to its substrate HMBPP (Gold.Chemscore.DG: -20.9734 kcal/mol). Among them, 5 were discarded because of their inhibitory activity towards other human enzymes. The rest 12 potential leads carry all the properties of any "drug like" molecule and the knowledge of Plasmodium LytB inhibitory mechanism which can provide valuable support for the antimalarial inhibitor design in future.

Current transport mechanism at metal-semiconductor nanoscale interfaces based on ultrahigh density arrays of p-type NiO nano-pillars

The present work focuses on a qualitative analysis of localised I-V characteristics based on the nanostructure morphology of highly dense arrays of p-type NiO nano-pillars (NiO-NPs). Vertically aligned NiO-NPs have been grown on different substrates by using a glancing angle deposition (GLAD) technique. The preferred orientation of as grown NiO-NPs was controlled by the deposition pressure. The NiO-NPs displayed a polar surface with a microscopic dipole moment along the (111) plane (Tasker's type III). Consequently, the crystal plane dependent surface electron accumulation layer and the lattice disorder at the grain boundary interface showed a non-uniform current distribution throughout the sample surface, demonstrated by a conducting AFM technique (c-AFM). The variation in I-V for different points in a single current distribution grain (CD-grain) has been attributed to the variation of Schottky barrier height (SBH) at the metal-semiconductor (M-S) interface. Furthermore, we observed that the strain produced during the NiO-NPs growth can modulate the SBH. Inbound strain acts as an external field to influence the local electric field at the M-S interface causing a variation in SBH with the NPs orientation. This paper shows that vertical arrays of NiO-NPs are potential candidates for nanoscale devices because they have a great impact on the local current transport mechanism due to its nanostructure morphology.

Identification of swamp deer (Cervus duvauceli duvauceli Cuvier) potential habitat in Jhilmil Jheel Conservation Reserve, Uttarakhand, India using multi-criteria analysis

The present study aims to identify the potential habitat for swamp deer (Cervus duvauceli duvauceli Cuvier) in Jhilmil Jheel Conservation Reserve in the Uttarakhand province of India using multi-criteria analysis. The study area represents one of the last remnant habitats of the flagship species, the swamp deer in Uttarakhand, which is considered as vulnerable. The study showed that only 6.08% of the study area (225 km(2)) was highly suitable to suitable for the swamp deer. An area of 135.52 km(2) (60.23%) turned out to be moderately suitable. Within the officially designated Conservation Reserve (area 37.84 km(2)), 10.91% (4.13 km(2)) area was found highly suitable to suitable, while 74.19% (28.07 km(2)) happens to be moderately suitable. Only 14 km(2) area, which was found as suitable habitat for swamp deer falls short of the space required by a population of 134 animals. The problem could be mitigated if the agricultural land (2.47 km(2)) adjacent to the Jhilmil Jheel is brought under the Reserve management. This would provide additional area to meet the fodder requirement. The study brings out a particularly grim situation with limited options for conservation and management of the swamp deer in the Indo-Gangetic plains. It also emphasizes the role of geospatial techniques in quick appraisal of habitat attributes and identification of potential sites for protected areas.

Enhanced p-type conductivity and band gap narrowing in heavily Al doped NiO thin films deposited by RF magnetron sputtering

Stoichiometric NiO, a Mott-Hubbard insulator at room temperature, shows p-type electrical conduction due to the introduction of Ni(2+) vacancies (V(Ni)('')) and self-doping of Ni(3+) ions in the presence of excess oxygen. The electrical conductivity of this important material is low and not sufficient for active device fabrication. Al doped NiO thin films were synthesized by radio frequency (RF) magnetron sputtering on glass substrates at a substrate temperature of 250 °C in an oxygen + argon atmosphere in order to enhance the p-type electrical conductivity. X-ray diffraction studies confirmed the correct phase formation and also oriented growth of NiO thin films. Al doping was confirmed by x-ray photoelectron spectroscopic studies. The structural, electrical and optical properties of the films were investigated as a function of Al doping (0-4 wt%) in the target. The room temperature electrical conductivity increased from 0.01-0.32 S cm (-1) for 0-4% Al doping. With increasing Al doping, above the Mott critical carrier density, energy band gap shrinkage was observed. This was explained by the shift of the band edges due to the existence of exchange and correlation energies amongst the electron-electron and hole-hole systems and also by the interaction between the impurity quasi-particle system.

Utilisation pattern of blood in a teaching hospital of Kolkata

An annual utilisation of blood transfusion services at several depts. of R.G. Kar Medical College and Hospital, Kolkata were assessed among a sample of 3122 patients selected by Systematic Random Sampling Technique from the register made available in the blood bank there. Record analysis revealed that overall 79.4% of supplied blood units were actually transfused, wastage of 21.6%. Wastage was maximum in the Department of Gynae & Obstetrics (33.11%) and Surgery (32.87%). Only single unit of blood was requisitioned and transfused for 5.44% & 30.90% of the patients respectively. Most common indications of blood transfusion were for surgical cases (37.92%), followed by anaemia (34.80%) and haemorrhage (26.92%). The use of blood and blood products merit attention, appraisal and instructional guiding accordingly.

Status of maternal and new born care at first referral units in the state of West Bengal

A study was conducted in 12 First Referral Units (FRUs), selected through multistage sampling, from 6 districts of West Bengal. Infrastructure facilities, record keeping, referral system and MCH indicators related to newborn care were documented. Data was collected by review of records, interview and observation using a pre-designed proforma. Inadequate infrastructure facilities (e.g. no sanctioned posts of specialists, no blood bank at rural hospitals declared as First Referral Units etc.); poor utilization of equipment like neonatal resuscitation sets, radiant warmer etc, lack of training of the service providers were evident. Records/registers were available but incomplete. Referral system was found to be almost nonexistent. Most of the deliveries (86.1%) were normal delivery. Deliveries (87.71%) and immediate neonatal resuscitation (94.9%) were done mostly by nursing personnel. Institution based maternal, perinatal and early neonatal mortality rates were found to be 5.6, 62.4 and 25.2 per 1000 live births respectively. Eclampsia (48.9%), hemorrhage (17.7%), puerperal sepsis (7.1%) were reported to be major causes of maternal mortality. Common causes of early neonatal mortality were birth asphyxia (54.3%), sepsis (14.6%) and prematurity/LBW (12.4%).

A patient with optic pathway glioma, scoliosis, Chiari type I malformation and syringomyelia: is it Neurofibromatosis type 1?

A 22 years old girl had features of optic pathway glioma, scoliosis, Chiari type 1 malformation and cervical syringomyelia. She had no cutaneous lesions. We considered this combination to be more than coincidental and argue in favour of considering the case as a variant form of Neurofibromatosis type 1. The relevent literature in favour of our contention has been reviewed.

What is health? Where GPs' and patients' worlds collide

Qualitative studies have highlighted the complexity of patient models of health. The present quantitative study aimed to compare general practitioners' (GPs) and patients' models of health. A questionnaire consisting of 27 'markers of health' was completed by 472 patients (response rate 78.8%) and 64 GPs (response rate 71%). The results showed that GPs and patients were comparable in their ratings of those markers relating to arousal, such as sleep, sex drive and energy and infections, such as neck glands and having lots of colds. However, in the main GPs and patients were consistently different. In particular, the patients showed a higher rating for those markers relating to digestion (e.g. appetite, bloatedness), bodily fluids (e.g. the colour and smell of urine, regularity of bowels), the condition of the tongue, hair and complexion and for more traditional medical markers (e.g. heart beat, body weight). In contrast, GPs reported higher ratings for mood and emotions. To conclude, patients appeared to hold much more diverse models of health than GPs and reported greater endorsement for markers consistent with both a humoral and medical approach to health. These results suggest that GPs and patients do not have a shared understanding of health, which has implications for the effectiveness of primary care consultations.

Analytical studies on the impact of land reclamation on ground water flow

Land reclamation has been a common practice to produce valuable land in coastal areas. The impact of land reclamation on coastal environment and marine ecology is well recognized and widely studied. It has not been recognized yet that reclamation may change the regional ground water regime, which may in turn modify the coastal environment, flooding pattern, and stability of slopes and foundations. This paper represents the first attempt to examine quantitatively the effect of reclamation on ground water levels. Analytical solutions are developed to study the ground water change in response to reclamation based on two hypothetical models. In the first model, the ground water flow regime changes only in the hillside around the reclamation areas. In the second model, the ground water regime changes in the entire hill. Both models assume that the ground water flow is in a steady state and satisfies the Dupuit assumptions. Hypothetical examples are used to demonstrate how the ground water level, ground water divide and ground water submarine discharge will change with the scale and hydraulic conductivity of the reclamation materials. The results show that the change of ground water regime depends mainly on the length of the reclaimed area and the values of hydraulic conductivity of the reclaimed materials. It is also seen that the reclamation may impact not only the ground water regime near the coast areas around the reclamation site, but also that in the coast areas opposite the reclamation area. A reclamation site near Tseung Kwan O in the New Territories in Hong Kong, China, is used as a case study to discuss the possible modification of the ground water system caused by reclamation.

Referral for minor mental illness: a qualitative study

BACKGROUND

Mild depression and anxiety are common problems in general practice. They can be managed by the general practitioner (GP) alone or referred. Previous quantitative studies have shown a large variation between GPs in terms of referral behaviour. The reasons for this variation are not fully understood.

AIM

To describe and analyse GP's decision-making processes when considering who should be treating patients with minor mental illness, using a qualitative method.

DESIGN OF STUDY

A qualitative interview study.

SETTING

Twenty-three GPs in east London and Essex.

METHOD

Subjects were chosen using a purposive sampling strategy and participated in one-to-one semi-structured interviews. A grounded theory approach was used for analysis.

RESULTS

Two distinct referral strategies were identified--the 'containment' and the 'conduit' approaches. In addition, referrals were found to be of two types--proactive 'referrals to' and reactive 'referrals away'; for minor mental illness the 'referrals away' were found to predominate. Emotive as well as rational responses informed GP decision making on referral.

CONCLUSIONS

Explanations of the variation in referral rates need to recognise the emotive responses of individual GPs to minor mental illness. The contribution of guidelines, which assume consistently rational responses to illness, may therefore be limited.

Sertraline treatment of generalized social phobia: a 20-week, double-blind, placebo-controlled study

OBJECTIVE

The authors evaluated the efficacy, safety, and tolerability of sertraline, a selective serotonin reuptake inhibitor, in the treatment of generalized social phobia.

METHOD

Adult outpatients with generalized social phobia (N=204) from 10 Canadian centers were randomly assigned to receive sertraline or placebo in a 2:1 ratio for a 20-week double-blind study following a 1-week, single-blind, placebo run-in. The initial dose of sertraline was 50 mg/day with increases of 50 mg/day every 3 weeks permitted after the fourth week of treatment (dosing was flexible up to a maximum of 200 mg/day). Primary efficacy assessments were the percentage of patients rated much or very much improved on the Clinical Global Impression (CGI) improvement item and the mean changes from baseline to study endpoint in total score on the social phobia subscale of the Marks Fear Questionnaire and total score on the Brief Social Phobia Scale.

RESULTS

In intent-to-treat endpoint analyses of 203 of the patients, significantly more of the 134 patients given sertraline (N=71 [53%]) than of the 69 patients receiving placebo (N=20 [29%]) were considered responders according to their CGI improvement scores at the end of treatment. The mean reductions in the social phobia subscale of the Marks Fear Questionnaire and in the total score on the Brief Social Phobia Scale were 32.6% and 34.3% in the sertraline group and 10.8% and 18.6% in the placebo group, respectively. Analysis of covariance showed superiority of sertraline over placebo on all primary and secondary efficacy measures. Sertraline was well tolerated: 103 (76%) of the 135 sertraline-treated patients and 54 (78%) of the 69 placebo-treated patients completed the study.

CONCLUSIONS

Sertraline is an effective treatment for patients with generalized social phobia.

Prevention of relapse in generalized social phobia: results of a 24-week study in responders to 20 weeks of sertraline treatment

The aim of this study was to evaluate the efficacy, tolerability, and effects on quality of life of sertraline, a selective serotonin reuptake inhibitor, in the prevention of relapse of generalized social phobia. Fifty adult outpatients with generalized social phobia who were rated much or very much improved on the Clinical Global Impression Scale of Improvement (CGI-I) after 20 weeks of sertraline treatment (50-200 mg/day) were randomly assigned in a one-to-one ratio to either continue double-blind treatment with sertraline or immediately switch to placebo for another 24 weeks. The initial 20-week study was placebo-controlled, and 15 responders to placebo also continued to receive double-blind placebo treatment in the continuation study. Eighty-eight percent of patients in the sertraline-continuation group and only 40% of patients in the placebo-switch and placebo-responder groups completed the study. In intent-to-treat endpoint analyses, 1 (4%) of 25 patients in the sertraline-continuation group and 9 (36%) of 25 patients in the placebo-switch group had relapsed at study endpoint (chi2 = 8.0, Fisher exact test, p = 0.01). The relative risk (hazards ratio) for relapse associated with placebo-switch relative to sertraline-continuation treatment was 10.2 (95% confidence interval, 1.3-80.7). Mean CGI-Severity, Marks Fear Questionnaire (MFQ) Social Phobia subscale, and Duke Brief Social Phobia Scale (BSPS) total scores were reduced by 0.07, 0.34, and 1.86 in the Sertraline-Continuation group and increased by 0.88, 4.09, and 5.99 in the Placebo-Switch group (all F > 5.3, p < 0.03), respectively. CGI-Severity, MFQ Social Phobia subscale, and BSPS scores also increased in the Placebo-Responder group. Discontinuations because of lack of efficacy were 4% in the sertraline-continuation group, 28% in the placebo-switch group (chi2 = 5.36, Fisher exact test, p = 0.049), relative to sertraline, and 27% in the placebo-responder group. Sertraline was effective in preventing relapse of generalized social phobia. Future research should assess whether improvements may be maintained or further increased by longer periods of treatment or through the addition of cognitive-behavioral techniques.

Evidence for new nuclear and mitochondrial genome organizations among high-frequency somatic embryogenesis-derived plants of allotetraploid Coffea arabica L. (Rubiaceae)

 The most important commercial species of coffee, Coffea arabica, which produces 73% of the world's coffee crop and almost all of the coffee in Latin America, is the only tetraploid (allotetraploid, 2n=4x=44) species known in the genus. High-frequency somatic embryogenesis, plant regeneration and plant recovery were achieved from leaf explants of a mature, elite plant of C. arabica cv. Cauvery (S-4347) using a two-step culture method. To assess the genetic integrity of the nuclear, mitochondrial and chloroplast genomes among the hardened regenerants, we employed multiple DNA markers (RFLP, RAPD, ISSR) for sampling various regions of the genome. Although the nuclear and mitochondrial genomes of the mother plant and five ramets derived from the mother ortet were similar in organization, this was not so in the somatic embryo-derived plants where both nuclear and mitochondrial genomes changed in different, characteristic ways and produced novel genome organizations. A total of 480 genetic loci, based on the data obtained from a total of 16 nuclear, mitochondrial and chloroplast gene probes, in combination with nine restriction enzyme digests, 38 RAPD and 17 SSR primers, were scored in 27 somatic embryo-derived plants and the single control. Among these, 44 loci were observed to be polymorphic. A relatively low level of polymorphism (4.36%) was found in the nuclear genome, while polymorphism in the mitochondrial genome (41%) was much higher. No polymorphism was detected in the chloroplast genome. The polymorphism in the mitochondrial genome was found in only 4 plants. Such selective polymorphism was not true for the nuclear genome. Thus, this in-depth and comprehensive study demonstrates, for the first time, the presence of subtle genetic variability and novel genome organizations in the commercially well-established somatic embryogenesis-derived plants of this important coffee species.

Missed opportunities for immunisation in children

All opportunities for immunisation in children should be utilised properly, as sustaining high levels of full immunisation coverage is essential to meet the goal of eradication of poliomyelitis as well as control the other vaccine-preventable diseases; yet many opportunities for immunisation are missed in all types of health facilities, even in teaching hospitals. Reducing such missed opportunities is the cheapest way to increase immunisation coverage. The present study discusses the problem of missed opportunities for immunisation in children in Paediatric Outpatient Department and Immunisation Clinic of R.G. Kar Medical and Hospital, Calcutta and the underlying factors of the problem. Prevalence of missed opportunities in Paediatric OPD and Immunisation clinic was 37.8% and 1.4% respectively. Most of the missed opportunities were attributed to health care providers and delivery system of health care of the studied hospital.