Nanodiamond-structured zinc composite coatings with strong bonding and high load-bearing capacity

The aerospace and automotive industries find that relying solely on the intrinsic resistance of alloys is inadequate to safeguard aircraft and automotive structural components from harsh environmental conditions. While it is difficult to attribute accidents exclusively to coating failure due to the involvement of multiple factors, there are instances where defects in the coating initiate a wear or degradation process, leading to premature and unplanned structural failures. Metallic coatings have been introduced to protect the aircraft mainly from wear due to the extreme temperatures and moisture exposure during their service life. Bare metallic coatings have a limited lifespan and need to be replaced frequently. Herein, the strength and wear resistance of zinc (Zn) coating is enhanced using varying concentrations of diamond particles as an additive in the Zn matrix (Zn-D). The dispersion strengthening mechanism is attributed to the high hardness (70 HRC), and reduced friction-of-coefficient (0.21) and dissipation energy (4.6 × 10-4 J) of electrodeposited Zn-D7.5 (7.5 g l-1 of diamond concentration) composite coating. Moreover, enhanced wear resistance with minimum wear volume (1.12 × 10-3 mm3) and wear rate (1.25 × 10-3 mm3 N-1 m-1) of the Zn-D7.5 composite coating resulted in perfect blending of diamond with Zn. The improved hardness and wear resistance for Zn-D7.5 (optimum 7.5 g l-1 diamond concentration) is due to the steadiness between well-dispersed diamonds in Zn and enrichment in load-bearing ability due to the incorporation of diamond particles. Electronic structure calculations on the zinc-diamond composite models (two configurations adopted) have been performed using the density functional theory (DFT) approach, and the in silico studies appeared to facilitate meaningful and evocative outcomes. Zn-doped diamond (C10@Zn) without hydrogen (H) atoms (binding energy: 418 kcal mol-1, i.e. showing an endothermic reaction and thermodynamically not favourable) was detected to be more stable than the Zn-doped diamond (C10H16@Zn) consisting of hydrogen (H) atoms (binding energy: -33.3 kcal mol-1, i.e. showing an exothermic reaction and thermodynamically preferable). Thus, a composite coating of zinc and diamond can be a suitable candidate for the aerospace and automotive industries.

Spectroscopic, Biological, and Topological Insights on Lemonol as a Potential Anticancer Agent

A monoterpene alcohol known as lemonol was investigated experimentally as well as theoretically in order to gain insights into its geometrical structure, vibrational frequencies, solvent effects on electronic properties, molecular electrostatic potential, Mulliken atomic charge distribution, natural bond orbital, and Nonlinear Optical properties. The frontier molecular orbital energy gap values of 5.9084 eV (gas), 5.9261 eV (ethanol), 5.9185 eV (chloroform), 5.9253 eV (acetone), and 5.9176 eV (diethyl ether) were predicted, and it shows the kinetic stability and chemical reactivity of lemonol. Topological studies were conducted using Multiwfn software to understand the binding sites and weak interactions in lemonol. The antiproliferative effect of lemonol against the breast cancer cell line Michigan Cancer Foundation (MCF-7) was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, while nuclear damage, condensation, and reactive oxygen species generation were identified using acridine orange/ethidium bromide, propidium iodide, and dichlorodihydrofluorescein diacetate staining. The theoretical and experimental findings are highly correlated, confirming the structure, and the results of in vitro studies suggest that lemonol acts as a potent inhibitor against the human breast cancer cell line MCF-7, highlighting its strong antiproliferative activity.

In-vitro anti-Mycobacterium tuberculosis effect of essential oil of Ocimum sanctum L. (Tulsi/Basil) leaves

BACKGROUND/OBJECTIVES

Mycobacterium tuberculosis, the causative agent of tuberculosis has developed resistance to most of the available antimicrobials. Consequently, it is difficult to cure all the patients with tuberculosis and in future, the incidence of tuberculosis by drug resistant M. tuberculosis is likely to increase, worldwide. Therefore detection and development of new antimicrobials against M. tuberculosis is needed urgently.

METHODS

Essential oil from the leaves of Ocimum sanctum L (Tulsi/Basil) was obtained by hydro distillation. The anti-mycobacterial effect of essential oil was evaluated against H37Rv and nine clinical isolates of M. tuberculosis in the BD BACTEC MGIT instrument using different volumes of essential oil.

RESULTS

The essential oil inhibited the growth of H37Rv and all the nine clinical isolates of M. tuberculosis. The minimal inhibitory concentration of H37Rv was 3 μl (2.931 μg) and those of the clinical isolates of M. tuberculosis ranged from 1.5 μl (1.4655 μg) to 6 μl (5.862 μg).

CONCLUSION

The Essential oil from the leaves of O. sanctum L.(Tulsi/Basil) has anti-M. tuberculosis effect in the in-vitro BD BACTEC MGIT method.

A novel biogenic Allium cepa leaf mediated silver nanoparticles for antimicrobial, antioxidant, and anticancer effects on MCF-7 cell line

In the present study, Allium cepa leaf extract was utilized to reduce the silver nitrate into the nanoscale range of silver ions (Ag NPs). The biosynthesized Ag NPs were extensively characterized by X-ray diffraction analysis (XRD), Dynamic light scattering analysis (DLS), UV-Visible spectroscopy (UV-vis), Transmission electron microscopy (TEM), Energy dispersive X-ray analysis (EDX) and Fourier transform infrared spectroscopy (FTIR). The antioxidant activity of synthesized Ag NPs was verified by DPPH assay. From the results obtained from XRD and DLS studies, the size of Ag NPs was determined to be around 54.3 nm. The measured zeta potential value of -19.1 mV confirms the excellent stability of biosynthesized Ag NPs. TEM analyses reveal that the biosynthesized Ag NPs have a spherical structure of 13 nm in size. The presence of various functional groups was confirmed through FTIR studies and EDAX verifies the weight percentage of silver content in biosynthesized nanoparticles to be 30.33%. In the present study, anti-cancer activity was carried out by using breast cancer cell line MCF-7. Further, silver nanoparticles exhibited antimicrobial effectiveness against gram-positive Bacillus cereus and gram-negative Escherichia coli. The MTT assay also showed better cytotoxic activity against the MCF- 7 cell line.

Serum uric acid, influence of sacubitril/valsartan, and cardiovascular outcomes in heart failure with preserved ejection fraction: PARAGON-HF

Background

Serum uric acid (SUA) is a biomarker of several pathobiologies relevant to the pathogenesis of heart failure with preserved ejection fraction (HFpEF), though by itself may also worsen outcomes. In HF with reduced EF, SUA is independently associated with adverse outcomes and sacubitril/valsartan reduces SUA compared to enalapril. These effects in HFpEF have not been delineated.

Purpose

To determine the prognostic value of SUA, relationship of change in SUA to quality of life and outcomes, and influence of sacubitril/valsartan on SUA in HFpEF.

Methods

We analyzed 4,795 participants from the Prospective Comparison of ARNI with ARB Global Outcomes in HF with Preserved Ejection Fraction (PARAGON-HF) trial. We related baseline hyperuricemia to the primary outcome (CV death and total HF hospitalization), its components, myocardial infarction or stroke, and a renal composite outcome. At the 4-month visit, the relationship between SUA change and Kansas City Cardiomyopathy Questionnaire overall summary score (KCCQ-OSS) and several biomarkers including N-terminal pro-B-type natriuretic peptide (NT-proBNP) were also assessed. We simultaneously adjusted for baseline and time-updated SUA to determine whether lowering SUA was associated with clinical benefit.

Results

Average age was 73±8 years and 52% were women. After multivariable adjustment, hyperuricemia was associated with increased risk for most outcomes (primary outcome HR 1.61, 95% CI 1.37, 1.90, Fig 1A). The treatment effect of sacubitril/valsartan for the primary outcome was not modified by baseline SUA (interaction p=0.11). Sacubitril/valsartan reduced SUA −0.38 mg/dL (95% CI: −0.45, −0.31) compared with valsartan (Fig 1B), with greater effect in those with baseline hyperuricemia (−0.50 mg/dL) (interaction p=0.013). Change in SUA was independently and inversely associated with change in KCCQ-OSS (p=0.019) and eGFR (p<0.001), but not NT-proBNP (p=0.52). Time-updated SUA was a stronger predictor of adverse outcomes over baseline SUA.

Conclusions

SUA independently predicts adverse outcomes in HFpEF. Sacubitril/valsartan significantly reduces SUA compared to valsartan, an effect that was stronger in those with higher baseline SUA, and reducing SUA was associated with improved outcomes.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Novartis

Peptidoglycan-treated tumor antigen-pulsed dendritic cells impart complete resistance against tumor rechallenge

Solid tumors elicit suppressive T cell responses which impair antigen-presenting cell (APC) functions. Such immune suppression results in uncontrolled tumor growth and mortality. Addressing APC dysfunction, dendritic cell (DC)-mediated anti-tumor vaccination was extensively investigated in both mice and humans. These studies never achieved full resistance to tumor relapse. Herein, we describe a repetitive RM-1 murine tumor rechallenge model for recurrence in humans. Using this newly developed model, we show that priming with tumor antigen-pulsed, Toll-like receptor (TLR)2 ligand-activated DCs elicits a host-protective anti-tumor immune response in C57BL/6 mice. Upon stimulation with the TLR2 ligand peptidoglycan (PGN), the tumor antigen-pulsed DCs induce complete resistance to repetitive tumor challenges. Intra-tumoral injection of PGN reduces tumor growth. The tumor resistance is accompanied by increased expression of interleukin (IL)-27, T-box transcription factor TBX21 (T-bet), IL-12, tumor necrosis factor (TNF)-α and interferon (IFN)-γ, along with heightened cytotoxic T lymphocyte (CTL) functions. Mice primed four times with PGN-stimulated tumor antigen-pulsed DCs remain entirely resistant to repeat challenges with RM-1 tumor cells, suggesting complete prevention of relapse and recurrence of tumor. Adoptive transfer of T cells from these mice, which were fully protected from RM-1 rechallenge, confers anti-tumor immunity to syngeneic naive recipient mice upon RM-1 challenge. These observations indicate that PGN-activated DCs induce robust host-protective anti-tumor T cells that completely resist tumor growth and recurrence.

Spectroscopic and structural investigations on modafinil by FT-IR, FT-Raman, NMR, UV-Vis and DFT methods

Chiral sulfoxide based smart drug modafinil were studied experimentally and theoretically. Vibrational spectra were recorded in the mid IR region and electronic spectra were recorded in UV-Visible region. The molecular geometry, vibrational spectra, magnetic spectra and electronic spectra were simulated using Density Functional Theory (DFT) employed with B3LYP/6-311++G(d,p) basis set. The molecular geometry optimization, vibrational frequencies, chemical shifts and solvent effect on electronic properties were reported. The intermolecular interactions have been studied by Hirshfeld surface analysis. There is good agreement was found between calculated and observed values, thereby to confirm the molecular structure of modafinil.

Monitoring regional blockade

This review attempts to draw on the published literature to address three practical clinical questions. First, what means of testing the degree of regional blockade pre-operatively are available, and can eventual success or failure be determined soon after injection? Second, is it possible to predict if a block inserted after the induction of general anaesthesia will be effective when the patient wakes? Third, what features, and what duration, should cause concern when a block does not resolve as expected after surgery? Although the relevant literature is limited, we recommend testing of multiple sensory modalities before surgery commences; temperature and thermographic changes may offer additional early warning of success or failure. There are a number of existing methods of assessing nociception under general anaesthesia, but none has yet been applied to gauge the onset of a regional block. Finally, criteria for further investigation and neurological referral when block symptoms persist postoperatively are presented.

The effects of serotonin modulation on medial prefrontal connectivity strength and stability: A pharmacological fMRI study with citalopram

BACKGROUND

Static and dynamic functional connectivity are being increasingly used to measure the effects of disease and a range of different interventions on brain networks. While preliminary evidence suggests that static connectivity can be modulated by chronic antidepressants administration in healthy individuals and in major depression, much less is known about the acute effects of antidepressants especially on dynamic functional connectivity changes. Here we examine acute effects of antidepressants on dynamic functional connectivity within the default mode network. The default mode network is a well described network with many functions in which the role of serotonin is not clear.

METHODS

In this work we measured acute pharmacological effects of an infusion of the selective serotonin reuptake inhibitor (SSRI) citalopram (10 mg) in a sample of thirteen healthy volunteers randomised to receive on two occasions the active compound or placebo in a cross over dosing.

RESULTS

Acute citalopram administration relative to placebo increased static connectivity between the medial prefrontal cortex and right dorsolateral prefrontal cortex and posterior cingulate cortex. The SSRI also induced a reduction in variability of connectivity with the medial prefrontal cortex in the precuneus and posterior cingulate cortex.

DISCUSSION

The measured changes are compatible with modified serotonin cortical availability.

A Molecular Approach to Immunoscintigraphy: A Study of the T-Antigen Conformation on the Surface of Tumors

The role of glycoconjugates in tumor cell differentiation has been well documented. We have examined the expression of the two anomers of the Thomsen-Friedenreich antigen on the surface of human, canine and murine tumor cell membranes both in vitro and in vivo. This has been accomplished through the synthesis of the disaccharide terminal residues in both a and ß configuration. Both entities were used to generate murine monoclonal antibodies which recognized the carbohydrate determinants. The determination of fine specificities of these antibodies was effected by means of cellular uptake, immunohistopathology and immunoscintigraphy. Examination of pathological specimens of human and canine tumor tissue indicated that the expressed antigen was in the β configuration. More than 89% of all human carcinomas tested expressed the antigen in the above anomeric form. The combination of synthetic antigens and monoclonal antibodies raised specifically against them provide us with invaluable tools for the study of tumor marker expression in humans and their respective animal tumor models.

Common and distinct patterns of grey-matter volume alteration in major depression and bipolar disorder: evidence from voxel-based meta-analysis

Finding robust brain substrates of mood disorders is an important target for research. The degree to which major depression (MDD) and bipolar disorder (BD) are associated with common and/or distinct patterns of volumetric changes is nevertheless unclear. Furthermore, the extant literature is heterogeneous with respect to the nature of these changes. We report a meta-analysis of voxel-based morphometry (VBM) studies in MDD and BD. We identified studies published up to January 2015 that compared grey matter in MDD (50 data sets including 4101 individuals) and BD (36 data sets including 2407 individuals) using whole-brain VBM. We used statistical maps from the studies included where available and reported peak coordinates otherwise. Group comparisons and conjunction analyses identified regions in which the disorders showed common and distinct patterns of volumetric alteration. Both disorders were associated with lower grey-matter volume relative to healthy individuals in a number of areas. Conjunction analysis showed smaller volumes in both disorders in clusters in the dorsomedial and ventromedial prefrontal cortex, including the anterior cingulate cortex and bilateral insula. Group comparisons indicated that findings of smaller grey-matter volumes relative to controls in the right dorsolateral prefrontal cortex and left hippocampus, along with cerebellar, temporal and parietal regions were more substantial in major depression. These results suggest that MDD and BD are characterised by both common and distinct patterns of grey-matter volume changes. This combination of differences and similarities has the potential to inform the development of diagnostic biomarkers for these conditions.

Highly sensitive determination of non-steroidal anti-inflammatory drug nimesulide using electrochemically reduced graphene oxide nanoribbons

Preparation of an electrochemically reduced graphene nanoribbon (ER-GONR) film modified screen-printed carbon electrode for the highly sensitive determination of nimesulide.

Pairwise contact energy statistical potentials can help to find probability of point mutations

To adopt a particular fold, a protein requires several interactions between its amino acid residues. The energetic contribution of these residue-residue interactions can be approximated by extracting statistical potentials from known high resolution structures. Several methods based on statistical potentials extracted from unrelated proteins are found to make a better prediction of probability of point mutations. We postulate that the statistical potentials extracted from known structures of similar folds with varying sequence identity can be a powerful tool to examine probability of point mutation. By keeping this in mind, we have derived pairwise residue and atomic contact energy potentials for the different functional families that adopt the (α/β)₈ TIM-Barrel fold. We carried out computational point mutations at various conserved residue positions in yeast Triose phosphate isomerase enzyme for which experimental results are already reported. We have also performed molecular dynamics simulations on a subset of point mutants to make a comparative study. The difference in pairwise residue and atomic contact energy of wildtype and various point mutations reveals probability of mutations at a particular position. Interestingly, we found that our computational prediction agrees with the experimental studies of Silverman et al. (Proc Natl Acad Sci 2001;98:3092-3097) and perform better prediction than i_Mutant and Cologne University Protein Stability Analysis Tool. The present work thus suggests deriving pairwise contact energy potentials and molecular dynamics simulations of functionally important folds could help us to predict probability of point mutations which may ultimately reduce the time and cost of mutation experiments. Proteins 2016; 85:54-64. © 2016 Wiley Periodicals, Inc.

Clinical Evaluation of Rapid Diagnostic Test Kit for Scrub Typhus with Improved Performance

Diagnosis of scrub typhus is challenging due to its more than twenty serotypes and the similar clinical symptoms with other acute febrile illnesses including leptospirosis, murine typhus and hemorrhagic fever with renal syndrome. Accuracy and rapidity of a diagnostic test to Orientia tsutsugamushi is an important step to diagnose this disease. To discriminate scrub typhus from other diseases, the improved ImmuneMed Scrub Typhus Rapid Diagnostic Test (RDT) was evaluated in Korea and Sri Lanka. The sensitivity at the base of each IgM and IgG indirect immunofluorescent assay (IFA) in Korean patients was 98.6% and 97.1%, and the specificity was 98.2% and 97.7% respectively. The sensitivity and specificity for retrospective diagnosis at the base of IFA in Sri Lanka was 92.1% and 96.1%. ImmuneMed RDT was not reactive to any serum from seventeen diseases including hemorrhagic fever with renal syndrome (n = 48), leptospirosis (n = 23), and murine typhus (n = 48). ImmuneMed RDT shows superior sensitivity (98.6% and 97.1%) compared with SD Bioline RDT (84.4% at IgM and 83.3% at IgG) in Korea. The retrospective diagnosis of ImmuneMed RDT exhibits 94.0% identity with enzyme-linked Immunosorbent assay (ELISA) using South India patient serum samples. These results suggest that this RDT can replace other diagnostic tests and is applicable for global diagnosis of scrub typhus. This rapid and accurate diagnosis will be beneficial for diagnosing and managing scrub typhus.

High frequency of mitochondrial DNA mutations in HIV-infected treatment-experienced individuals

OBJECTIVES

We recently observed a decrease in deoxyribonucleotide (dNTP) pools in HIV-infected individuals on antiretroviral therapy (ART). Alterations in dNTPs result in mutations in mitochondrial DNA (mtDNA) in cell culture and animal models. Therefore, we investigated whether ART is associated with mitochondrial genome sequence variation in peripheral blood mononuclear cells (PBMCs) of HIV-infected treatment-experienced individuals.

METHODS

In this substudy of a case-control study, 71 participants were included: 22 'cases', who were HIV-infected treatment-experienced patients with mitochondrial toxicity, 25 HIV-infected treatment-experienced patients without mitochondrial toxicity, and 24 HIV-uninfected controls. Total DNA was extracted from PBMCs and purified polymerase chain reaction (PCR) products were subjected to third-generation sequencing using the PacBio Single Molecule Real-Time (SMRT) sequencing technology. The sequences were aligned against the revised Cambridge reference sequence for human mitochondrial DNA (NC_012920.1) for detection of variants.

RESULTS

We identified a total of 123 novel variants, 39 of them in the coding region. HIV-infected treatment-experienced patients with and without toxicity had significantly higher average numbers of mitochondrial variants per participant than HIV-uninfected controls. We observed a higher burden of mtDNA large-scale deletions in HIV-infected treatment-experienced patients with toxicity compared with HIV-uninfected controls (P = 0.02). The frequency of mtDNA molecules containing a common deletion (mt.δ4977) was higher in HIV-infected treatment-experienced patients with toxicity compared with HIV-uninfected controls (P = 0.06). There was no statistically significant difference in mtDNA variants between HIV-infected treatment-experienced patients with and without toxicity.

CONCLUSIONS

The frequency of mtDNA variants (mutations and large-scale deletions) was higher in HIV-infected treatment-experienced patients with or without ART-induced toxicity than in uninfected controls.

Analysis of secondary structural and physicochemical changes in protein-protein complexes

Conformation switching in protein-protein complexes is considered important for the molecular recognition process. Overall analysis of 123 protein-protein complexes in a benchmark data-set showed that 6.8% of residues switched over their secondary structure conformation upon complex formation. Amino acid residue-wise preference for conformation change has been analyzed in binding and non-binding site residues separately. In this analysis, residues such as Ser, Leu, Glu, and Lys had higher frequency of secondary structural conformation change. The change of helix to coil and sheet to coil conformation and vice versa has been observed frequently, whereas the conformation change of helix to extended sheet occurred rarely in the studied complexes. Influence of conformation change toward the N and C terminal on either side of the binding site residues has been analyzed. Further, analysis on φ and ψ angle variation, conservation, stability, and solvent accessibility have been performed on binding site residues. Knowledge obtained from the present study could be effectively employed in the protein-protein modeling and docking studies.

The practical management of refractory schizophrenia--the Maudsley Treatment REview and Assessment Team service approach

OBJECTIVE

To describe a practical approach to the community management of treatment-resistant schizophrenia (TRS).

METHOD

A descriptive review of an approach to the assessment and management of patients with TRS, including the community titration of clozapine treatment, and a report of the management recommendations for the first one hundred patients assessed by the Treatment REview and Assessment Team (TREAT).

RESULTS

The standardized model for the community assessment, management and titration of clozapine is described. To date, 137 patients have been referred to this service and 100 patients (72%) attended for assessment. Of these, 33 have been initiated on clozapine while fifteen have had clozapine recommended but have not wished to undertake clozapine treatment. Other management options recommended have included augmentation strategies and long-acting injectable antipsychotics.

CONCLUSION

The service had increased the number of patients receiving community assessment and initiation of clozapine by five-fold relative to the rate prior to the establishment of the service. The large number of referrals and high attendance rate indicates that there is clinical demand for the model. Systematic evaluation is required to determine the clinical and cost-effectiveness of this model and its potential application to other clinical settings.

Metal complexes of ONO donor Schiff base ligand as a new class of bioactive compounds: synthesis, characterization and biological evolution

Present work reviews that, the synthesis of (E)-N'-((7-hydroxy-4-methyl-2-oxo-2H-chromen-8-yl)methylene)benzohydrazide [L] ligand and their metal complexes. The colored complexes were prepared of type [M(2+)L]X2, where M(2+)=Mn, Co, Ni, Cu, Sr and Cd, L=(7-hydroxy-4-methyl-2-oxo-2H-chromen-8-yl)methylene)benzohydrazide, X=Cl(-). Ligand derived from the condensation of 8-formyl-7-hydroxy-4-methylcoumarin and benzohydrazide in the molar ratio 1:1 and in the molar ratio 1:2 for metal complexes have been prepared. The chelation of the ligand to metal ions occurs through the both oxygen groups, as well as the nitrogen atoms of the azomethine group of the ligand. Reactions of the Schiff base ligand with Manganese(II), Cobalt(II), Nickel(II), Copper(II), Strontium(II), and Cadmium(II) afforded the corresponding metal complexes. The structures of the obtained ligand and their respective metal complexes were elucidated by infra-red, elemental analysis, Double beam UV-visible spectra, conductometric measurements, magnetic susceptibility measurements and also thermochemical studies. The metal complex exhibits octahedral coordination geometrical arrangement. Schiff base ligand and their metal complexes were tested against antioxidants, antidiabetic and antimicrobial activities have been studied. The Schiff base metal complexes emerges effective α-glucosidase inhibitory activity than free Schiff base ligand.

Socio-economic patterning of tobacco use in Indian states

BACKGROUND

Studies in India have identified marked variations in overall tobacco use between socio-economic groups. We examined whether associations between socio-economic status (SES) and tobacco use varied across individual Indian states by tobacco type.

METHODS

Cross-sectional survey of 100,855 households in 24 Indian states and Union Territories conducted in 2009-2010. Outcome measures were household tobacco consumption by type. Logistic and linear regression models were used to examine associations at the household level between education, income and use and volume of tobacco consumed.

RESULTS

Overall, 52% of households used any form of tobacco product; the predominant form was smokeless tobacco (22%), followed by bidi (17%) and cigarettes (4%). Increasing household income and higher education level were associated with a higher likelihood of cigarette use but a lower likelihood of bidi and smokeless tobacco use in some Indian states. Increasing household income was associated with higher volumes of cigarette and bidi use among consuming households; however, association between educational level and volume of tobacco consumption was inconsistent.

CONCLUSION

SES has a varying impact on different types of tobacco use in Indian states. Policy makers should consider socio-economic patterning of tobacco use when designing, implementing and evaluating tobacco control interventions in different states of India.

Role of pretransplant echocardiographic evaluation in predicting outcomes following liver transplantation

Maintenance of cardiac function is critical to the survival of patients with end-stage liver disease after liver transplantation (LT). We sought to determine whether pre-LT echocardiographic indices of right heart structure and function were independently predictive of morbidity and mortality post-LT. We retrospectively studied 216 consecutive patients who underwent pre-LT 2-dimensional/Doppler echocardiography with subsequent LT from 2007 to 2010. A blinded reader analyzed multiple echocardiographic parameters, including right ventricular structure and function, pulmonary artery systolic pressure (PASP) and the presence and severity of tricuspid regurgitation (TR). On univariate analysis, Model of End-Stage Liver Disease (MELD) score, PASP, presence of ≥mild TR, post-operative renal replacement therapy (RRT) and spontaneous bacterial peritonitis were found to be significant predictors of adverse outcomes. On multivariate analysis, only ≥mild TR was found to predict both patient mortality (p = 0.0024, HR = 3.91, 95% CI: 1.62-9.44) and graft failure (p = 0.0010, HR = 3.70, 95% CI: 1.70-8.06). PASP and MELD correlated with post-LT intensive care unit length of stay (LOS) and, along with hemodialysis, were associated with hospital LOS and time on ventilator. In conclusion, pre-LT echocardiographic assessments of the right heart may be useful in predicting post-LT morbidity and mortality and guiding the selection of appropriate LT candidates.

Short-term SSRI treatment normalises amygdala hyperactivity in depressed patients

BACKGROUND

Antidepressant drugs such as selective serotonin re-uptake inhibitors (SSRIs) remediate negative biases in emotional processing in depressed patients in both behavioural and neural outcome measures. However, it is not clear if these effects occur before, or as a consequence of, changes in clinical state.

METHOD

In the present study, we investigated the effects of short-term SSRI treatment in depressed patients on the neural response to fearful faces prior to clinical improvement in mood. Altogether, 42 unmedicated depressed patients received SSRI treatment (10 mg escitalopram daily) or placebo in a randomised, parallel-group design. The neural response to fearful and happy faces was measured on day 7 of treatment using functional magnetic resonance imaging. A group of healthy controls was imaged in the same way.

RESULTS

Amygdala responses to fearful facial expressions were significantly greater in depressed patients compared to healthy controls. However, this response was normalised in patients receiving 7 days treatment with escitalopram. There was no significant difference in clinical depression ratings at 7 days between the escitalopram and placebo-treated patients.

CONCLUSIONS

Our results suggest that short-term SSRI treatment in depressed patients remediates amygdala hyperactivity in response to negative emotional stimuli prior to clinical improvement in depressed mood. This supports the hypothesis that the clinical effects of antidepressant treatment may be mediated in part through early changes in emotional processing. Further studies will be needed to show if these early effects of antidepressant medication predict eventual clinical outcome.

From the prodrome to chronic schizophrenia: the neurobiology underlying psychotic symptoms and cognitive impairments

Schizophrenia is a chronic psychotic disorder that remains a considerable cause of global disease burden. Cognitive impairments are common and contribute significantly to the morbidity of the disorder. Over the last two decades or so molecular imaging studies have refined understanding of the pathophysiology underlying the development of psychosis and cognitive impairments. Firstly they have consistently implicated presynaptic dopaminergic dysfunction in the disorder, finding that dopamine synthesis capacity, dopamine release and baseline dopamine levels are increased in the illness. Secondly recent findings show that dopamine synthesis capacity is elevated in those that go on to develop psychosis in the following year, but not in those that do not, and appears to increase further with the development of psychosis. Thirdly evidence links greater dopamine synthesis capacity to poorer cognitive performance and altered frontal cortical function measured using functional imaging during cognitive tasks. Finally they have provided data on the nature of other neurofunctional alterations in the disorder, in particular in the serotonergic system and neuroinflammation. We review these findings and discuss their implications for understanding the neurobiology of psychosis and cognitive impairments in schizophrenia.

Antiobiotic resistance pattern of biofilm-forming uropathogens isolated from catheterised patients in Pondicherry, India

BACKGROUND

Microbial biofilms pose a public health problem for persons requiring indwelling medical devices, as micro-organisms in biofilms are difficult to treat with antimicrobial agents. Thus the present study includes biofilm formation and antibiotic resistance pattern of uropathogens in hospitalised patients with catheter associated urinary tract infections (UTI).

METHOD

This prospective analysis included 100 urine samples from catheterised patients with symptoms of UTI over a period of six months. Following identification, all isolates were subjected to antibiotic sensitivity using modified Kirby- Bauer disc diffusion method. Detection of biofilms was done by tube adherence method and Congo red agar method.

RESULTS

E.coli was found to be the most frequently isolated uropathogen 70%, followed by Klebsiella pneumoniae 16%, Pseudomonas aeruginosa 4%, Acinetobacter spp 2%, coagulase negative Staphylococci 6% and Enterococci Spp 2%. In the current study 60% of strains were in vitro positive for biofilm production. Biofilm positive isolates showed 93.3%, 83.3%, 73.3% and 80% resistance to nalidixic acid, ampicillin, cephotaxime and cotrimoxazole, respectively, compared to 70%, 60%, 35%, 60% resistance showed by biofilm non-producers for the respective antibiotics. Approximately 80% of the biofilm producing strains showed multidrug resistant phenotype

CONCLUSION

To conclude E.coli was the most frequent isolate, of which 63% were biofilm producers. The antibiotic susceptibility pattern in the present study showed quinolones were the least active drug against uropathogens. The uropathogens showed the highest sensitivity to carbapenems. The next best alternatives were aminoglycosides. Significant correlation between biofilm production and multi-drug resistance was observed in our study.

Comparison of different techniques of cataract surgery in bacterial contamination of the anterior chamber in diabetic and non-diabetic population

Aim:

To compare the bacterial contamination of the anterior chamber (AC) between manual small incision cataract surgery (SICS) and phacoemulsification (Phaco). To study the conjunctival flora and bacterial contamination of AC between well-controlled diabetics and non-diabetics.

Materials and Methods:

Three hundred and sixty-eight patients were randomized to manual SICS and Phaco. Sixty-eight patients were excluded for not completing follow-up or for intraoperative complications like posterior capsule rupture. One hundred and fifty patients in each group were finally analyzed. Conjunctival swabs were taken on admission, after one day of topical ofloxacin and 15 min after 5% Povidone Iodine (PI) instillation. AC aspirate at the end of the surgery was also cultured.

Results:

Fifty-six (18.66%) patients had positive conjunctival swab on admission which was reduced to 19 (6.33%) with topical ofloxacin and to five (1.66%) with instillation of 5% PI. AC contamination in both manual SICS and Phaco was 0.66%. The conjunctival flora in diabetics was similar to non-diabetics. None of the diabetics had AC contamination. Statistical analysis was performed by Chi-Square test (with Yates’ correction).

Conclusion:

Statistically significant reduction in conjunctival flora was achieved with topical ofloxacin and 5% PI instillation and AC contamination in both manual SICS and Phaco was minimal (0.66%). Well-controlled diabetics who underwent cataract surgery in this study had similar conjunctival flora and AC contamination as non-diabetics.

Correlation of trace elemental profiles in blood samples of Indian patients with leukoplakia and oral submucous fibrosis

In order to ascertain possible correlation between alterations in trace elemental profile and the progression or regression of two most common potentially malignant disorders affecting oral cavity, namely oral submucous fibrosis and leukoplakia, blood from 60 patients from each group of patients as well from 30 healthy individuals was analyzed for elemental profiling employing EDXRF technique. Out of the 16 detected elements (K, Si, Ca, V, Cr, Ni, Mn, Fe, Cu, Zn, Se, Br, Rb, Sr, Co, and Pb), Mn, Fe, Zn, Br, and Co showed remarkable alteration in their profile in both leukoplakia and oral submucous fibrosis patients with respect to the normal healthy individuals. While Zn, Br, and Fe reflected similar changes--showing gross depletion in both the diseased groups, Mn and Co depicted inverse pattern of alterations in their concentrations in the two types of precancerous disorders when compared to the control subjects.