Recent progress in MoS2 nanostructures for biomedical applications: Experimental and computational approach

In the category of 2D materials, MoS2 a transition metal dichalcogenide, is a novel and intriguing class of materials with interesting physicochemical properties, explored in applications ranging from cutting-edge optoelectronic to the frontiers of biomedical and biotechnology. MoS2 nanostructures an alternative to heavy toxic metals exhibit biocompatibility, low toxicity and high stability, and high binding affinity to biomolecules. MoS2 nanostructures provide a lot of opportunities for the advancement of novel biosensing, nanodrug delivery system, electrochemical detection, bioimaging, and photothermal therapy. Much efforts have been made in recent years to improve their physiochemical properties by developing a better synthesis approach, surface functionalization, and biocompatibility for their safe use in the advancement of biomedical applications. The understanding of parameters involved during the development of nanostructures for their safe utilization in biomedical applications has been discussed. Computational studies are included in this article to understand better the properties of MoS2 and the mechanism involved in their interaction with biomolecules. As a result, we anticipate that this combined experimental and computational studies of MoS2 will inspire the development of nanostructures with smart drug delivery systems, and add value to the understanding of two-dimensional smart nano-carriers.

Impact of luminescent MoSe2 quantum dots on activity of trypsin under different pH environment

It is vital that a straightforward detection approach for trypsin should be developed as it is important diagnostic tool for a number of diseases. Herein, the impact of luminescent MoSe2 quantum dots on trypsin activity under different pH environment has been studied. Addition of trypsin to MoSe2 quantum dots enhanced the fluorescence of quantum dots whereas quantum dots resulted in quenching of fluorescence of trypsin. The quenching behavior at various pH and temperature was examined and revealed that the MoSe2-trypsin complex stabilized through the electrostatic interactions. The obtained negative values of zeta potential of the complex -0.11 mV, -0.30 mV and -0.59 mV for pH 6.0,7.6 and 9.0 respectively confirmed the stability of the complex. The separation between the donor and acceptor atoms in energy transfer mechanism was found to decrease (1.48 nm to 1.44 nm to 1.30 nm) with increasing value of pH. It was also evident that trypsin retained its enzyme activity in the trypsin-MoSe2 complex and under different pH environment. The Vant Hoff plot from quenching revealed 1 binding site for quantum dots by trypsin for all pH of buffer solution. The complex formation of trypsin-MoSe2 quantum dots was verified for the first time using fluorescence spectroscopy and it revealed that tryspin form complex with MoSe2 quantum dots through electrostatic interactions. Our results revealed that the MoSe2 quantum dots stabilized and sheltered the active sites of trypsin, which was likely the cause of the increased bioavailability of MoSe2 quantum dots in enzymes.

Antioxidants supplementation improves the quality of in vitro produced ovine embryos with amendments in key development gene expressions

The present study assessed the effects of supplementation of different antioxidants on oocyte maturation, embryo production, reactive oxygen species (ROS) production and expression of key developmental genes. In this study, using ovine as an animal model, we tested the hypothesis that antioxidant supplementation enhanced the developmental competence of oocytes. Ovine oocytes aspirated from local abattoir-derived ovaries were subjected to IVM with different concentrations of antioxidants [(Melatonin, Ascorbic acid (Vit C), alpha-tocopherol (Vit E), Sodium selenite (SS)]. Oocytes matured without any antioxidant supplementation were used as controls. The oocytes were assessed for maturation rates and ROS levels. Further, embryo production rates in terms of cleavage, blastocysts and total cell numbers were evaluated after performing in vitro fertilization. Real-Time PCR analysis was used to evaluate the expression of stress related gene (SOD-1), growth related (GDF-9, BMP-15), and apoptosis-related genes (BCL-2 and BAX). We observed that maturation rates were significantly higher in alpha-tocopherol (100 μM; 92.4%) groups followed by melatonin (30 μM; 89.1%) group. However, blastocyst rates in ascorbic acid (100 μM; 19.5%), melatonin (30 μM; 18.4%), alpha-tocopherol (100 μM; 18.2%), and sodium selenite (20 μM; 16.9%) groups were significantly higher (P 0.05) than that observed in the control groups. Total cell numbers in blastocysts in the melatonin, ascorbic acid and alpha-tocopherol groups were significantly higher than those observed in sodium selenite and control groups. ROS production was reduced in groups treated with melatonin (30 μM), vitamin C (100 μM), sodium selenite (20 μM) and α-tocopherol (200 μM) compared with that observed in the control group. Supplementation of antioxidants caused the alterations in mRNA expression of growth, stress, and apoptosis related gene expression in matured oocytes. The results recommend that antioxidants alpha-tocopherol (200 μM), sodium selenite (40 μM), melatonin (30 μM) and ascorbic acid (100 μM) during IVM reduced the oxidative stress by decreasing ROS levels in oocytes, thus improving embryo quantity and quality.

A systematic comparison of FOSL1, FOSL2 and BATF-mediated transcriptional regulation during early human Th17 differentiation

Th17 cells are essential for protection against extracellular pathogens, but their aberrant activity can cause autoimmunity. Molecular mechanisms that dictate Th17 cell-differentiation have been extensively studied using mouse models. However, species-specific differences underscore the need to validate these findings in human. Here, we characterized the human-specific roles of three AP-1 transcription factors, FOSL1, FOSL2 and BATF, during early stages of Th17 differentiation. Our results demonstrate that FOSL1 and FOSL2 co-repress Th17 fate-specification, whereas BATF promotes the Th17 lineage. Strikingly, FOSL1 was found to play different roles in human and mouse. Genome-wide binding analysis indicated that FOSL1, FOSL2 and BATF share occupancy over regulatory regions of genes involved in Th17 lineage commitment. These AP-1 factors also share their protein interacting partners, which suggests mechanisms for their functional interplay. Our study further reveals that the genomic binding sites of FOSL1, FOSL2 and BATF harbour hundreds of autoimmune disease-linked SNPs. We show that many of these SNPs alter the ability of these transcription factors to bind DNA. Our findings thus provide critical insights into AP-1-mediated regulation of human Th17-fate and associated pathologies.

Interactome Networks of FOSL1 and FOSL2 in Human Th17 Cells

Dysregulated function of Th17 cells has implications in immunodeficiencies and autoimmune disorders. Th17 cell differentiation is orchestrated by a complex network of transcription factors, including several members of the activator protein (AP-1) family. Among the latter, FOSL1 and FOSL2 modulate the effector functions of Th17 cells. However, the molecular mechanisms underlying these effects are unclear, owing to the poorly characterized protein interaction networks of FOSL factors. Here, we establish the first interactomes of FOSL1 and FOSL2 in human Th17 cells, using affinity purification-mass spectrometry analysis. In addition to the known JUN proteins, we identified several novel binding partners of FOSL1 and FOSL2. Gene ontology analysis found a significant fraction of these interactors to be associated with RNA-binding activity, which suggests new mechanistic links. Intriguingly, 29 proteins were found to share interactions with FOSL1 and FOSL2, and these included key regulators of Th17 fate. We further validated the binding partners identified in this study by using parallel reaction monitoring targeted mass spectrometry and other methods. Our study provides key insights into the interaction-based signaling mechanisms of FOSL proteins that potentially govern Th17 cell differentiation and associated pathologies.

A sustainable approach towards utilization of plastic waste for an efficient electrode in microbial fuel cell applications

Microbial fuel cells (MFC) are a novel technique for power generation from wastewater. A number of approaches for the modification of physical as well as chemical properties of the electrodes can be employed to attain the maximum output power density and high power electricity. The use of an active organic linker, extracted from waste residue (plastic), for the synthesis of porous nanostructured materials would be beneficial in the fabrication of electrodes for MFC. Herein, terephthalic acid monomer (t) derived from plastic waste was successfully applied as an electrochemically active linking unit to form an iron-based metal-organic framework (Fe-t-MOF: MIL-53(Fe)). The synthesized Fe-t-MOF was further modified with conducting polymer (polyaniline (PANI)). The produced nanocomposite (Fe-t-MOF/PANI) was coated on stainless steel (SS) disk (as a current collector) for use as an electrode component of the MFC system. The power density, open circuit potential (OCP), and a limiting current density of the MFC are 680 mW/m², 0.67 V, and 3500mA/m², respectively. The technique opted here should help search a novel, efficient, sustainable, and cost-effective route for the modification of the plastic waste into an MFC electrode to achieve bioenergy production through wastewater treatment.

Soil fertility and rice productivity in shifting cultivation: impact of fallow lengths and soil amendments in Lengpui, Mizoram northeast India

An exponential increase in the human population has drastically reduced the length of fallow period (<5 years) in widely spread shifting cultivation (Jhum). This has increased the invasion of weeds and decreased soil fertility and crop productivity, and consequently raised concern of food security for the local farming communities. The present study was conducted in two jhum fallows (FL-10 and FL-15) to understand the response of fallow length and applications of indigenous soil microbes and rock phosphate on the levels of soil fertility and crop productivity. The results showed greater soil physicochemical properties in FL-15 compared to FL-10. Burning significantly increased the levels of soil pH, avail P, avail N in the soil, whereas, the same decreased the levels of soil C, MBC and SM in both the sites. Among treatments, the synergistic effect of rock phosphate and microbial inocula showed greater improvement in soil biochemical properties, and showed a climactic increase over control in crop productivity and rice yield in all sites. Maximum rice grain yield and productivity was recorded in FL-15 followed by FL-10. This study concludes that a mixture of rock phosphate and microbial inocula from the rhizosphere soil of early regenerating plant is effective in increasing soil fertility and crop productivity, and can be used as an important tool to sustain crop productivity and food security in the region.

QbD-steered development and validation of an RP-HPLC method for quantification of ferulic acid: Rational application of chemometric tools

The present work describes the systematic development of a simple, rapid, sensitive, robust, effective and cost-effective reversed-phase high performance liquid chromatographic method for quantitative analysis of ferulic acid using analytical quality by design paradigms. Initially, apt wavelength for the analysis of ferulic acid was selected employing principal component analysis as the chemometric tool. An Ishikawa fishbone diagram was constructed to delineate various plausible variables influencing analytical target profile, viz. peak area, theoretical plate count, retention time and peak tailing as the critical analytical attributes. Risk assessment using risk estimation matrix and factor screening studies employing Taguchi design aided in demarcating two critical method parameters, viz. mobile phase ratio and flow rate affecting critical analytical attributes. Subsequently, the optimum operational conditions of the liquid chromatographic method were delineated using face-centred composite design. Multicollinearity among the chosen factors for optimization was analyzed by the magnitude of variance inflation factor optimized analytical design space, providing optimum method performance, was earmarked using numerical and graphical optimization and corroborated using Monte Carlo simulations. Validation, as per the ICH Q2(R1) guidelines, ratified the efficiency and sensitivity of the developed novel analytical method of ferulic acid in the mobile phase and the human plasma matrix. The optimal method used a mobile phase, comprising of acetonitrile: water (47:53% v/v, pH adjusted to 3.0 with glacial acetic acid), at a flow rate of 0.8 mL·min^-1, at a λ_max of 322 nm using a C₁₈ column. Use of principal component analysis unearthed the suitable wavelength for analysis, while analytical quality by design approach, along with Monte Carlo simulations, facilitated the identification of influential variables in obtaining the "best plausible" validated chromatographic solution for efficient quantification of ferulic acid.

Effect on Morphology and Optical Properties of Inorganic and Hybrid Perovskite Semiconductor Thin Films Fabricated Layer by Layer

In recent time, organic-inorganic halide perovskite solar cells govern photovoltaic field, due to its remarkable development on the power conversion process. Still, large variations in device efficiency and basic physical properties are reported. This is due to variations during film fabrications and consecutive treatments employed. Here, we report a layer by layer deposition of inorganic perovskite (CsBi₃I₁₀) and lead halide perovskite (CH₃NH₃PbI₃) thin films. We find that the absorbance for corresponding thin film goes on increasing dramatically. UV-vis spectrum of film recorded to find the band gap of films, ˜1.55 eV optical band gap have been obtained for the film fabricated layer by layer. We further study the fabrication of different perovskite layers impact on microstructure, surface morphology and optical properties. The optical and structural characterization outcomes all suggests the perovskite films processed by using the layer by layer fabrication are well controlled, making this processes an auspicious technique to fabricate thin-films for numerous prospective device applications and scientific studies.

Effects of Thermal Annealing Duration on the Film Morphology of Methylamine Lead Triiodide (MAPbI₃) Perovskite Thin Films in Ambient Air

In the present communication we have studied the effect of thermal annealing duration on morphology of methylamine lead triiodide (MAPbI₃) perovskite (prepared using single step method) semiconductor that changes into lead iodide (PbI₂). Furthermore, the effect of annealing duration on thin films is investigated and correlated with its potential photovoltaic application. Thin films characteristics study by X-ray diffraction and scanning electron microscopy results indicate MAPbI₃ degraded strongly by annealing duration. However, thin films (about 1.25 micron-thick) annealed at 80 °C for 10 min in ambient conditions cause minimum degradation with smooth and uniform surface morphology. It also shows a higher absorption coefficient with the band gap of °1.5 eV rendering this perovskite suitable for practical applications.

Transcriptional Repressor HIC1 Contributes to Suppressive Function of Human Induced Regulatory T Cells

Regulatory T (Treg) cells are critical in regulating the immune response. In vitro induced Treg (iTreg) cells have significant potential in clinical medicine. However, applying iTreg cells as therapeutics is complicated by the poor stability of human iTreg cells and their variable suppressive activity. Therefore, it is important to understand the molecular mechanisms of human iTreg cell specification. We identified hypermethylated in cancer 1 (HIC1) as a transcription factor upregulated early during the differentiation of human iTreg cells. Although FOXP3 expression was unaffected, HIC1 deficiency led to a considerable loss of suppression by iTreg cells with a concomitant increase in the expression of effector T cell associated genes. SNPs linked to several immune-mediated disorders were enriched around HIC1 binding sites, and in vitro binding assays indicated that these SNPs may alter the binding of HIC1. Our results suggest that HIC1 is an important contributor to iTreg cell development and function.

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Hypermethylated in cancer 1 (HIC1) is upregulated in iTreg cells

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HIC1-deficient iTreg cells express FOXP3 but have reduced suppressive ability

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Autoimmune-disease-associated SNPs are enriched within HIC1 binding loci

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HIC1 is an important regulator of iTreg development and function

Characteristics and mechanism associated with drug conjugated inorganic nanoparticles

Nanoparticles have several exciting applications nowadays almost in every area. Biomedical field is one of them where nanoparticles show potential for various applications due to their exceptional and exciting properties. The presence of heavy metals in inorganic nanoparticles lead to toxicity in the biological system, therefore, their direct use for drug delivery is restricted. But encapsulating their surface with a non-toxic or biocompatible material makes them a promising material for application in drug delivery system. This review highlights the various characteristics and factors involved in nano-drug delivery system. The understanding of various mechanisms involved during the uptake of nanoparticles by cells, toxicity, surface chemistry and several drug release mechanisms has been discussed. This article also includes various computational studies used to optimise the design and properties of drug delivery system.

Effect of size and silica coating on structural, magnetic as well as cytotoxicity properties of copper ferrite nanoparticles

Copper ferrite nanoparticles, synthesized by conventional sol-gel method were calcined at different temperatures. The magnetic, structural, morphological and cytotoxicity analyses of the uncalcined and calcined nanoparticles (NPs) were investigated and compared. Formation of tetragonal structure of CuFe₂O₄ NPs was observed in XRD patterns. On increasing the temperature, better crystallinity and increased crystallite size were also observed. In the FTIR spectra, bonds corresponding to CH, OH and carboxylate groups gradually disappeared with increasing temperature, while peak corresponding to FeO existed more prominently. NPs calcined at 300 °C (Cu3) exhibited the highest magnetic saturation and lowest retentivity, thereby indicating its superparamagnetic behaviour. Concentration-dependent cytotoxicity values were obtained by invitro MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide, a tetrazole) assay, Cell Titer assay and Cell Flow Cytometry with Propidium Iodide. NPs calcined at 300 °C, 500 °C and 700 °C exhibited non-toxicity at all the concentrations. Based on magnetic and biocompatibility analyses, Cu3 NPs were found to be the most suitable one to investigate the influence of silica coating on its surface. Presence of silica was confirmed by XRD pattern, FTIR spectrum, SEM and HRTEM micrographs as well as SAED pattern. In M-H curve, superparamagnetic behaviour of the CuFe₂O₄ core was retained but with reduced magnetic saturation due to magnetically dead layer of silica. An increase in cellular viability was witnessed in case of silica coated CuFe₂O₄ NPs as compared to uncoated NPs, thus reflecting on its enhanced biocompatibility. Nanosized, superparamagnetic and highly biocompatible characteristics make silica coated CuFe₂O₄ NPs a potential claimant for biomedical applications.

Nutritional and metabolic stressors on ovine oocyte development and granulosa cell functions in vitro

The present study was undertaken to study the effect of ammonia, urea, non-esterified fatty acid (NEFA), and β-hydroxybutyric acid (β-OHB) on oocyte development and granulosa cell (GC) growth parameter of ovine (Ovis aries). Ovine oocytes were matured in vitro in the presence of different concentration of ammonia, urea, NEFA, and β-OHB for 24 h, in vitro inseminated and evaluated for cleavage and blastocyst yield. Same concentrations of ammonia, urea, NEFA, and β-OHB were examined on growth parameters and hormone secretion activity of granulosa cells in vitro. Real-time reverse transcription polymerase chain reaction was used to evaluate the expression of steroidogenic genes (steroidogenic cytochrome P-450 (CYP11A1, CYP19A1)), cell proliferation-related genes (GDF9, FSHr), and apoptosis-related genes (BCL-2 and BAX). The maturation, cleavage, and blastocyst production rates were significantly lowered in media containing either 200 μM ammonia or 5 mM urea or high combo NEFA or 1 μM β-OHB. Exposure of granulosa cell to 400 μM ammonia or 1 μM β-OHB or very high combo or 6 mM urea significantly decreased all the parameters examined compared to lower levels of all nutritional and metabolic stressors. Elevated concentration of metabolic stressors induced GC apoptosis through the BAX/BCL-2 pathway and reduced the steroidogenic gene messenger RNA (mRNA) expression and cell proliferation gene mRNA expression. These results suggested that the decreased function of GCs may cause ovarian dysfunction and offered an improved understanding of the molecular mechanism responsible for the low fertility in metabolic stressed condition.

Structure and vibrations of glutathione studied by vibrational spectroscopy and density functional theory

The vibrational properties of glutathione have been investigated by infrared absorption and Raman spectroscopic techniques, and density functional theory calculations at the B3LYP/6-31+G(d,p) level. Assignments of all the experimentally observed vibrational bands have been done with the help of simulated vibrational spectra and potential energy distribution calculations of glutathione water cluster, which includes the effect of hydrogen bonding. Optimized molecular parameters of energy minimized structure have been compared with the available experimental values. Calculated molecular parameters of glutathione-water cluster match well with the experimental values. Some of the calculated molecular parameters and vibrational frequencies of vapor phase glutathione-water cluster suggest participation of some atoms of glutathione in hydrogen bonding. Experimentally observed UV-Visible absorption spectrum of glutathione has also been reported. Observed band at 203 nm has been assigned to electronic transitions calculated with time dependent density functional theory.

Investigation of trypsin-CdSe quantum dot interactions via spectroscopic methods and effects on enzymatic activity

The paper presents the interactions between trypsin and water soluble cadmium selenide (CdSe) quantum dots investigated by spectrophotometric methods. CdSe quantum dots have strong ability to quench the intrinsic fluorescence of trypsin by a static quenching mechanism. The quenching has been studied at three different temperatures where the results revealed that electrostatic interactions exist between CdSe quantum dots and trypsin and are responsible to stabilize the complex. The Scatchard plot from quenching revealed 1 binding site for quantum dots by trypsin, the same has been confirmed by making isothermal titrations of quantum dots against trypsin. The distance between donor and acceptor for trypsin-CdSe quantum dot complexes is calculated to be 2.8 nm by energy transfer mechanisms. The intrinsic fluorescence of CdSe quantum dots has also been enhanced by the trypsin, and is linear for concentration of trypsin ranging 1-80 μl. All the observations evidence the formation of trypsin-CdSe quantum dot conjugates, where trypsin retains the enzymatic activity which in turn is temperature and pH dependent.

Pesticide use pattern among farmers in a rural district of West Bengal, India

Background:

A vast majority of Indian population are engaged in agriculture. While pesticides help in increasing crop production, inappropriate pesticide storage practice and inadequate protective measures frequently causes accidental poisoning among farmers.

Objective:

The present study was conducted to explore the pattern of pesticide use among farmers in a district of India with an attempt to identify the lacunae in their knowledge and awareness level on risks and hazards of pesticides use.

Materials and Methods:

A cross-sectional questionnaire based study was conducted in the district of Burdwan, West Bengal, to address the study objective. Data analysis was performed by using descriptive statistical methods: Frequency, percentage, mean, standard deviation.

Results:

In the present study alpha-cypermethrin (46%) was the most commonly used pesticide followed by methyl parathion (25.6%), imidacloprid (16.4%), dichlorvos (7.8%) and phorate (4.2%). The farmers used to store pesticides mostly in cowshed (48.4%) followed by storeroom (29.6%). During spraying of pesticides, farmers experienced headache (29.8%) followed by nausea (26%), burning sensation in eyes (9.8%), cough (9.2%), muscle cramps (2%). Regarding the personal protective measures taken by the farmers for spraying, covering nose, mouth with cloth combined with bath after spraying was the most common practice (27%). When asked about suggested actions to be taken if anybody becomes sick following exposure to pesticides, 86% of farmers prefer consulting a doctor.

Conclusion:

The study suggested that farmers of Burdwan were exposed to highly hazardous, restricted and banned pesticides, with insufficient protection. In this situation, educational and training interventions on pesticide handling and safety precautions are urgently needed.

Guanine-copper coordination polymers: crystal analysis and application as thin film precursors

Three copper-N9-modified guanine complexes are reported with structures ranging from a discrete trinuclear motif to a mixed-valence coordination polymer. These complexes were used as precursors for the deposition and growth of copper oxide thin films on Si(100), at two different annealing temperatures, by using a CVD technique. Subsequent resistivity measurements suggest the formation of conductive thin films, raising the possibility of using nucleobase-metal complexes as versatile thin film precursors.

Vibrational and electronic spectroscopic studies of melatonin

We report the infrared absorption and Raman spectra of melatonin recorded with 488 and 632.8 nm excitations in 3600-2700 and 1700-70 cm(-1) regions. Further, we optimized molecular structure of the three conformers of melatonin within density functional theory calculations. Vibrational frequencies of all three conformers have also been calculated. Observed vibrational bands have been assigned to different vibrational motions of the molecules on the basis of potential energy distribution calculations and calculated vibrational frequencies. Observed band positions match well with the calculated values after scaling except NH stretching mode frequencies. It is found that the observed and calculated frequencies mismatch of NH stretching is due to intermolecular interactions between melatonin molecules.

Identification of potential HIV-1 integrase strand transfer inhibitors: in silico virtual screening and QM/MM docking studies

HIV-1 integrase (IN) is a retroviral enzyme that catalyses integration of the reverse-transcribed viral DNA into the host genome, which is necessary for efficient viral replication. In this study, we have performed an in silico virtual screening for the identification of potential HIV-1 IN strand transfer (ST) inhibitors. Pharmacophore modelling and atom-based 3D-QSAR studies were carried out for a series of compounds belonging to 3-Hydroxypyrimidine-2,4-diones. Based on the ligand-based pharmacophore model, we obtained a five-point pharmacophore with two hydrogen bond acceptors (A), one hydrogen bond donor (D), one hydrophobic group (H) and one aromatic ring (R) as pharmacophoric features. The pharmacophore hypothesis AADHR was used as a 3D query in a sequential virtual screening study to filter small molecule databases Maybridge, ChemBridge and Asinex. Hits matching with pharmacophore hypothesis AADHR were retrieved and passed progressively through Lipinski's rule of five filtering, molecular docking and hierarchical clustering. The five compounds with best hits with novel and diverse chemotypes were subjected to QM/MM docking, which showed improved docking accuracy. We further performed molecular dynamics simulation and found three compounds that form stable interactions with key residues. These compounds could be used as a leads for further drug development and rational design of HIV-1 IN inhibitors.

Open grade III fractures of femoral shaft: Outcome after early reamed intramedullary nailing

BACKGROUND

Open grade III fractures of femur are a challenging therapeutic problem as most of them are associated with multiple trauma. Method used for skeletal stabilization of these fractures should limit further soft tissue damage, bacterial spread and morbidity in addition to its ease of application, providing mechanical support and restoring normal alignment.

METHODS

Forty-six patients with open grade III fractures of femoral shaft were included in the study. There were 10 grade IIIA, 34 grade IIIB and two grade IIIC fractures that were treated with early reamed intramedullary nailing with adequate management of soft tissue. Patients were reviewed retrospectively.

RESULTS

Mean time of union was 27 weeks. Infection rate was 4% and non-union rate was 9%. There were two cases (4%) with limb shortening. No case of angular or rotational deformity was noted.

CONCLUSION

Early reamed intramedullary nailing for open grade III fractures of femoral shaft, after giving due respect to the soft tissue injury, gives satisfactory results with proper alignment, good range of motion, short rehabilitation period and low infection rate.

LEVEL OF EVIDENCE

Level IV. Retrospective therapeutic study.

Gellan gum-PEI nanocomposites as efficient gene delivery agents

Of the non-viral vectors, a cationic polymer like PEI is an attractive candidate which however, has been negatively impacted due to its marked toxicity. An anionic sugar polymer gelan gum (GG) has been introduced into PEI system to increase transfection efficiency with minimal toxicity. We showed that one of the synthesized (GP1-GP6) GG-PEI nanocomposites (NCs), GP3, exhibited negligible toxicity in in vitro (primary keratinocytes, HEK293, HeLa and HepG2 cells) and in vivo (Drosophila melanogaster) as compared to PEI or lipofectamin. GP3-pDNA complex was found to be transfected efficiently in the above cells as confirmed by FACS analysis (72.0 + 5.5%) while lipofectamine showed only 12.4 + 3.5% efficiency. GP3 mediated GFP specific siRNA delivery resulted in the knockdown of the GFP expression by approximately 77% and JNK (60%). In vivo gene expression studies in mice revealed reporter gene expression in spleen. The study demonstrates that GG blended PEI NCs hold promise for future applications in gene delivery both in vitro and in vivo.

Assessment of contamination of soil due to heavy metals around coal fired thermal power plants at Singrauli region of India

In the present study, an attempt was made to measure contamination of soil around four large coal-based Thermal Power Plants. The concentration of Cadmium, Lead, Arsenic and Nickel was estimated in all four directions from Thermal Power Plants. The soil in the study area was found to be contaminated to varying degrees from coal combustion byproducts. The soil drawn from various selected sites in each direction was largely contaminated by metals, predominantly higher within 2-4 km distance from Thermal Power Plant. Within 2-4 km, the mean maximum concentration of Cadmium, Lead, Arsenic and Nickel was 0.69, 13.69, 17.76, and 3.51 mg/kg, respectively. It was also observed that concentration was maximum in the prevalent wind direction. The concentration of Cadmium, Lead, Arsenic and Nickel was highest 0.69, 13.23, 17.29 and 3.56 mg/kg, respectively in west direction where wind was prevalent.

Zinc phthalocyanine thin film and chemical analyte interaction studies by density functional theory and vibrational techniques

Thin films of zinc phthalocyanine have been deposited on KBr and glass substrates by the thermal evaporation method and characterized by the x-ray diffraction, optical, infrared and Raman techniques. The observed x-ray diffraction and infrared absorption spectra of as-deposited thin films suggest the presence of an α crystalline phase. Infrared and Raman spectra of thin films after exposure to vapours of ammonia and methanol have also been recorded. Shifts in the position of some IR and Raman bands in the spectra of exposed films have been observed. Some bands also show changes in their intensity on exposure. Increased charge on the phthalocyanine ring and out-of-plane distortion of the core due to interaction between zinc phthalocyanine and vapour molecules involving the fifth coordination site of the central metal ion may be responsible for the band shifts. Changes in the intensity of bands are interpreted in terms of the lowering of molecular symmetry from D(4h) to C(4v) due to doming of the core. Molecular parameters and Mulliken atomic charges of zinc phthalocyanine and its complexes with methanol and ammonia have been calculated from density functional theory. The binding energy of the complexes have also been calculated. Calculated values of the energy for different complexes suggest that axially coordinated vapour molecules form the most stable complex. Calculated Mulliken atomic charges show net charge transfer from vapour molecules to the phthalocyanine ring for the most stable complex.

Effect of pyridine on infrared absorption spectra of copper phthalocyanine

Infrared absorption spectra of copper phthalocyanine in KBr pellet and pyridine solution in 400-1625 and 2900-3200 cm(-1)regions are reported. In the IR spectra of solid sample, presence of weak bands, which are forbidden according to the selection rules of D4h point group, is explained on the basis of distortion in the copper phthalocyanine molecule caused by the crystal packing effects. Observation of a new band at 1511 cm(-1) and change in intensity of some other bands in pyridine are interpreted on the basis of coordination of the solvent molecule with the central copper ion.

The effect of aluminium phosphide on the human brain: a histological study

The study was conducted on 317 cases of poisoning in the Varanasi region, India, between January 2002 and August 2003. Aluminium phosphide (Celphos) was used by 239 victims (75.40% of the total) and was used in 69.03% of male and 30.96% of female cases. It was commoner in males from both rural and urban areas and in the 21-30 year age group. Microscopic investigation of the cerebral and cerebellar cortex showed distinct changes due to the effect of celphos. Findings in the cerebral cortex revealed disorganisation of the different layers, round shaped neurons with a convex border, degenerated Nissl granules in the cytoplasm and a deeply stained degenerated eccentric nucleus. Findings in the cerebellar cortex included degenerated neurons, the infiltration of round cells into the molecular layer and the disappearance of the processes of Purkinje cells. Degenerate nuclei were surrounded by scavenger cells in the granular layer. The subcortical zone of the brain revealed a paucity of glial cells, degeneration of nerve fibres and the appearance of necrotic patches.

A study on drug use in a district hospital of West Bengal

A cross-sectional study at Howrah General Hospital, West Bengal for prescription analysis and assessment of drug dispensing in 341 patients revealed that the average number of drugs prescribed per encounter was 2.98 +/- 1.69, 38.2% drugs were in generic name and majority were from essential drugs list. 18.6% and 5.2% encounters used antibiotics and injections respectively. Average consultation and dispensing time were short. Majority of drugs were dispensed but unlabeled. 46.8% patients knew correct dosage of drugs. Only 4.7% patients were treated without drugs. Average drug cost per encounter was Rs. 31.32+30.89 where antibiotics and injections shared 36.5% and 4.6% respectively.

Infrared spectroscopic studies of free-base tetraphenylporphine and its dication

We present here the infrared absorption spectra of free-base tetraphenylporphine and its dication. Most of the allowed IR bands of porphyrin skeletal are observed in pairs due to two-fold symmetry of the free-base tetraphenylporphine. Observation of some new bands, disappearance of few bands in the IR spectrum of dication are interpreted on the basis of point group symmetry S4. Intensity change in the observed bands due to vibrational motion of the phenyl rings for dication is also explained on the basis of symmetry of dication. Sharing of electrons of the B(1u) orbitals by the two added protons are responsible for the shifts in the position of certain IR bands for dication.

Spectroscopic studies of rhodamine 6G dispersed in polymethylcyanoacrylate

We report here electronic absorption, fluorescence and resonance Raman studies of rhodamine 6G laser dye dispersed in the polymethylcyanoacrylate matrix. In the electronic absorption and fluorescence spectra of dispersed rhodamine 6G, band maxima are red shifted compared to solution. Raman spectra show some new bands. These spectral changes arise due to matrix effect and interaction between rhodamine 6G and the host material involving amine group of rhodamine.

Anatomical variations in termination of the axillary artery and its clinical implications

Variations in the termination of the axillary artery (AA) were observed in 51 out of 356 axilla during routine dissections. The incidence of variation was higher on the right axilla in 17.42% cases (CI: 11.60-22.51) than the left axilla 11.24% cases (CI: 6.46-15.55) and was found to be 12.33% in male and 40.63% in female cadavers. The variations were divided into four groups. The first group showed that the terminal end of the AA divided into lateral and medial divisions in 6.16% (CI: 2.21-9.82) male and in 15.63% (CI: 2.76-25.25) female cadavers. The second group variation showed that the terminal end of the axillary artery divided into deep and superficial divisions in 2.74% (CI: 0.10-5.27) male and in 6.25% (CI: -1.87-13.13) female cadavers. The third group showed that the terminal end of the AA divided into three branches in 2.74% (CI: 0.10-5.27) male and in 6.25% (CI: -1.87-13.13) female cadavers. The fourth group showed the tapering of the terminal end of AA in 0.68% (CI: -0.63-1.99) male and 12.50% (CI: 0.97-21.46) female cadavers. The variable origin of the circumflex humeral, subscapular and profunda brachii arteries was also observed. These variations in the terminal end of the axillary artery are not only of significant clinical importance to orthopaedic and reconstructive surgeons but also have very significant medico-legal implications.

Prescribing and dispensing activities at the health facilities of a non-governmental organization

BACKGROUND

Prescribing and dispensing surveys are pre-requisites to achieving rational drug use. There is a dearth of such studies in India, particularly in the non-governmental organization sector.

METHODS

We carried out a survey at the outpatient facilities maintained by the Southern Health Improvement Samity, a non-governmental organization in the South 24 Parganas district of West Bengal. Data were collected prospectively by interviewing patients immediately after patient-physician and patient-dispenser encounters. Pre-designed forms were used to collect data pertaining to World Health Organization drug-use indicators and some additional indices. The calculations of cost of therapy involved some approximation.

RESULTS

Of the 312 prescriptions analysed, the majority were signed, legible and complete with respect to age/gender data; 95.5% used Latin abbreviations and 7.7% mentioned neither signs and symptoms nor diagnosis. The average number of drugs per encounter was 3.2; only 2 patients were treated without drugs; 46.2% of drugs were prescribed by generic name. Use of antibiotics (72.8% of encounters) and irrational fixed dose combinations (45.6% of prescribed drugs) were frequent, but injection use (3.9% of prescriptions) was low. The average drug cost per encounter was Rs 74.19, of which antibiotics comprised 37.1%. The availability of first-line antitubercular drugs was adequate but other key drugs were in limited supply. Essential drugs lists and formularies were not followed. Only 45.7% of prescribed drugs conformed to the World Health Organization model list of essential drugs. Only 12 preparations accounted for 70.9% of the prescribed drugs, including therapeutically doubtful ones such as cough syrups, multivitamins and carminative syrups. For the dispensing survey, 301 prescriptions were analysed separately. All the prescribed drugs were supplied for only 11.6% of prescriptions. There were no serious errors in dispensing but 43.8% of dispensed products were inadequately labelled. Patients knew the correct mode of use for 64.5% of dispensed drugs. The average consultation and dispensing times were 3.7 and 3.1 minutes, respectively.

CONCLUSION

Frequent use of antibiotics, irrational fixed dose combinations and preparations of uncertain efficacy, inadequate labelling of dispensed drugs and lack of access to standard tools for rational drug use such as locally adapted essential drugs list, formularies and standard treatment guidelines were some of the problematic prescribing and dispensing trends identified through this survey. Educational interventions are required to rectify these problems.

Evaluation of antimuscarinic activity in human volunteers: a teaching aid in clinical pharmacology

The antimuscarinic activity of oxyphenonium bromide, diphenhydramine hydrochloride and astemizole were evaluated in six volunteers. The parameters used were salivary secretion, heart rate and pupillary size. The results indicated that the changes in heart rate and pupillary size and measurements were not convenient parameters for class room demonstration. However, salivary secretion and dryness of mouth were found to be reliable parameters for measurement. It was concluded that simple procedures like evaluation of antimuscarinic activity could be introduced as teaching aids in clinical pharmacology for undergraduate students.

Influence of high fat diet on steady state bioavailability of lithium carbonate in manic depressive patients - a preliminary report

The effect of high fat food in the steady state bioavailability of lithium carbonate (900 or 1200mg daily, in divided doses) was studied in three patients of manic-depressive psychosis in a self-control cross-over design. Serial blood samples were collected by venepuncture until 8 hours following drug administration and lithium was assayed by flame photometry. The results indicated a reduction in the extent of bioavailability of lithium by the high fat food as compared to standard normal diet, in all the three patients studied Caution should be exercised in regard to lithium administration along with food rich in fat content.

Comparative bioavailability of two enteric-coated capsules of omeprazole in healthy volunteers

A comparative bioavailability study was carried out on two enteric-coated capsules (20 mg each) of omeprazole (omeprazole, Alembic: "A" and Losec, Astra, England: "B"). The in-vitro dissolution of both products "A" and "B" met the prescribed USP standard. The bioavailability of single dose (20 mg) and multiple doses (20 mg once daily for 7 days) of both products "A" and "B" were carried out in eight healthy male volunteers in a crossover design. The rate and extent of bioavailability of omeprazole was higher in product "A" following a single oral dose, suggesting its therapeutic advantage over the product "B" in the prevention of acid aspiration during surgery. In multiple dose study, the two products were found bioequivalent as assessed by AUC0-infinity, Cmax, tmax and t1/2 elimination.

Effect of fatty diet on pharmacokinetics and pharmacodynamics of a liquid theophylline preparation in volunteers

The effect of a standard breakfast and a fatty breakfast on the pharmacokinetics and pharmacodynamics of a theophylline liquid preparation (160 mg-single dose) was examined in 6 healthy, non-smoking male volunteers. The plasma theophylline concentrations after both standard and fatty diet were found to be comparable at each point of time and pharmacokinetic parameters like Cmax, Tmax, T1/2a, T1/2 beta and AUC0-alpha, were also comparable. However, the time taken to attain the therapeutic plasma concentration was earlier and sustained along with the standard breakfast in comparison to that with fatty breakfast. Peak change in PEFR and pulse rate was also observed earlier with the standard diet than with fatty diet. The plasma theophylline concentrations produced after both diets were insufficient to produce any detectable change in subjective symptoms like tremor palpitation, heart burn, nausea, restlessness and tenseness. However, theophylline after fatty breakfast was better tolerated than that after a standard breakfast.