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1.
Chemosphere ; 287(Pt 4): 132286, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34600349

ABSTRACT

Coal is primarily a fuel material but lately it has been utilized as an adsorbent for removing toxic metal ions. However, its usage for removing organic pollutants is not well studied. We report here a systematic study on the use of coal samples of varying carbon contents as adsorbents for removing Basic Blue 41 as a model cationic dye. The coal samples were collected from coal mines and were thoroughly characterized. The concentrations of carbon, hydrogen, oxygen, nitrogen and sulphur contents were measured by CHNS analyzer. The concentrations of aluminum, silicon, sulphur, titanium and iron were determined by EDXRF, which corresponded to silicon dioxide (quartz) and aluminium silicate (kaolinite) as the major mineral inclusions, corroborated by XRD results and micrographs showing elemental maps determined from SEM-EDAX. The coal samples with low carbon content revealed higher adsorption capacity (qe âˆ¼ 8.0-9.3 mg/g) of Basic Blue dye at optimized adsorbent dose (2 mg/mL), pH 9 and contact time (120 min). The adsorption kinetic studies satisfied pseudo second order model and the intra-particle diffusion of the dye was evident. The dye adsorption followed Langmuir adsorption isotherm, and the qmax values ranged between 17 and 30 mg/g for low carbon content coal. The FT-IR, Brunauer-Emmett-Teller (BET) surface area and zeta potential results of the coal samples could explain the adsorption phenomenon of cationic dye. The kinetic and thermodynamic studies revealed that the adsorption of Basic Blue 41 dye was based on chemisorptions mechanism.


Subject(s)
Coal , Water Pollutants, Chemical , Adsorption , Carbon , Hydrogen-Ion Concentration , Kinetics , Spectroscopy, Fourier Transform Infrared , Thermodynamics , Water Pollutants, Chemical/analysis
2.
Biomed Pharmacother ; 142: 112090, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34463266

ABSTRACT

BACKGROUND: MicroRNAs play an important role in health and disease. TGF-ß signaling, upregulated by HIV Tat, and in chronic airway diseases and smokers upregulates miR-145-5p to suppress cystic fibrosis transmembrane conductance regulator (CFTR). CFTR suppression in chronic airway diseases like Cystic Fibrosis, COPD and smokers has been associated with suppressed MCC and recurrent lung infections and inflammation. This can explain the emergence of recurrent lung infections and inflammation in people living with HIV. METHODS: Tat-induced aberrant microRNAome was identified by miRNA expression analysis. microRNA mimics and antagomirs were used to validate the identified miRNAs involved in Tat mediated CFTR mRNA suppression. CRISPR-based editing of the miRNA target sites in CFTR 3'UTR was used to determine rescue of CFTR mRNA and function in airway epithelial cell lines and in primary human bronchial epithelial cells exposed to TGF-ß and Tat. FINDINGS: HIV Tat upregulates miR-145-5p and miR-509-3p. The two miRNAs demonstrate co-operative effects in suppressing CFTR. CRISPR-based editing of the miRNA target site preserves CFTR mRNA and function in airway epithelial cells INTERPRETATION: Given the important roles of TGF-ß signaling and the multitude of genes regulated by miRNAs, we demonstrate that CRISPR-based gene-specific microRNA antagonism approach can preserve CFTR mRNA and function in the context of HIV Tat and TGF-ß signaling without suppressing expression of other genes regulated by miR-145-5p.


Subject(s)
Cystic Fibrosis Transmembrane Conductance Regulator/genetics , MicroRNAs/genetics , RNA, Messenger/genetics , tat Gene Products, Human Immunodeficiency Virus/metabolism , 3' Untranslated Regions/genetics , Bronchi/cytology , CRISPR-Cas Systems/genetics , Cell Line , Cells, Cultured , Epithelial Cells/metabolism , Gene Editing , Humans , Signal Transduction/genetics , Transforming Growth Factor beta/metabolism , Up-Regulation
3.
Crit Rev Biomed Eng ; 48(3): 169-176, 2020.
Article in English | MEDLINE | ID: mdl-33389894

ABSTRACT

Clustered regularly interspaced palindromic repeats (CRISPR) technique plays a vital role in preclinical modelling of many respiratory diseases. Diseases such as chronic obstructive pulmonary disease (COPD), asthma, acute tracheal bronchitis, pneumonia, tuberculosis, lung cancer, and influenza infection continue to significantly impact human health. CRISPR associated (Cas) proteins, isolated from the immune system of prokaryotes, are one component of a very useful technique to manipulate gene sequences or editing and gene expression with significant implications for respiratory research in the field of molecular biology. CRISPR technology is a promising tool that is easily adaptable for specific editing of DNA sequences of interest with a goal towards modifying or eliminating gene function. Among its many potential applications, CRISPR can be applied to correcting genetic defects as well as for therapeutic approaches for treatment. This review elucidates recent advances in CRISPR-Cas technology in airway diseases.


Subject(s)
CRISPR-Cas Systems , Gene Editing , CRISPR-Cas Systems/genetics , Humans , Technology
4.
Sci Rep ; 9(1): 12552, 2019 08 29.
Article in English | MEDLINE | ID: mdl-31467373

ABSTRACT

Combination antiretroviral therapy (cART) has increased the life expectancy of HIV patients. However, the incidence of non-AIDS associated lung comorbidities, such as COPD and asthma, and that of opportunistic lung infections have become more common among this population. HIV proteins secreted by the anatomical HIV reservoirs can have both autocrine and paracrine effects contributing to the HIV-associated comorbidities. HIV has been recovered from cell-free bronchoalveolar lavage fluid, alveolar macrophages, and intrapulmonary lymphocytes. We have recently shown that ex-vivo cultured primary bronchial epithelial cells and the bronchial brushings from human subjects express canonical HIV receptors CD4, CCR5 and CXCR4 and can be infected with HIV. Together these studies suggest that the lung tissue can serve as an important reservoir for HIV. In this report, we show that TGF-ß1 promotes HIV latency by upregulating a transcriptional repressor BLIMP-1. Furthermore, we identify miR-9-5p as an important intermediate in TGF-ß-mediated BLIMP-1 upregulation and consequent HIV latency. The transcriptionally suppressed HIV can be reactivated by common latency reactivating agents. Together our data suggest that in patients with chronic airway diseases, TGF-ß can elevate the HIV viral reservoir load that could further exacerbate the HIV associated lung comorbidities.


Subject(s)
Bronchi/cytology , Cell Differentiation , Epithelial Cells/cytology , HIV-1/physiology , Transforming Growth Factor beta1/pharmacology , Viral Load/drug effects , Virus Latency/drug effects , Adaptor Proteins, Signal Transducing/genetics , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Epithelial Cells/virology , HIV-1/drug effects , Humans , MicroRNAs/genetics , Positive Regulatory Domain I-Binding Factor 1/genetics , RNA, Messenger/genetics , Signal Transduction/drug effects , Transcription Factors/genetics , Transforming Growth Factor beta1/metabolism
5.
J Nanosci Nanotechnol ; 18(4): 2686-2694, 2018 Apr 01.
Article in English | MEDLINE | ID: mdl-29442944

ABSTRACT

Here we present a simple yet efficient analytical method for sensing ultratrace levels of Hg2+ ions by highly water soluble CdS quantum dots functionalized with thiourea as a probe. The bluish photoluminescence emission of the probe responded to a systematic linear photoluminescence quenching in the presence of increasing concentration of Hg2+ ions. The photoluminescence quenching by Hg2+ ions was attributed to agglomeration of the quantum dots, which has been confirmed by zeta potential measurements. The sensitivity (31.38 L/mg) and LoD (0.11 µg/L) of Hg2+ ion detection by our method are two folds improved with respect to the existing data of CdS as sensor. The improved detection is attributable to synthesis of less than 3 nm diameter CdS quantum dots which rendered very high water solubility and hence facilitated better interaction with Hg2+ ions. The detection of Hg2+ ion was free from most interfering cations and anions, except for minor interference from Cu2+ and Pb2+ corresponding their concentrations expected in ground water. Further, the scope for visual detection of Hg2+ was explored, which revealed naked eye recognizable photoluminescence quenching of the probe treated 0.3 mg/L of Hg2+ ion when excited by a light source of 365 nm. The suitability of our probe to analyze Hg2+ in real samples has been demonstrated by Hg2+ spike analysis in groundwater and river water samples.

6.
Anal Sci ; 33(5): 565-571, 2017.
Article in English | MEDLINE | ID: mdl-28496059

ABSTRACT

Presented here is a simple yet rapid and efficient analytical method for visual as well as spectroscopic method for sensing of trace concentrations of Cu2+ ions in aqueous medium by systematic photoluminescence quenching of a highly water soluble probe made of CdS quantum dots surface modified by thiourea. The salient features of this work describe rapid detection (2 min equilibration time) of Cu2+ ions at wider linear concentration range (0.025 - 10 mg/L) corresponding to a sensitivity of 2.81(mg/L)-1 and limit of quantification of 47.3 µg/L, respectively, suitable for Cu2+ sensing in drinking water and ground water. Further, the detection of Cu2+ ion was free from most interfering cations and anions, except for minor interference from Cr3+, Hg2+ and Pb2+. The robustness of our probe for Cu2+ sensing is demonstrated from efficient Cu2+ spike recovery analysis in groundwater and river water samples.

7.
Waste Manag ; 64: 182-189, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28285732

ABSTRACT

A novel approach is presented to capture some of the potentially toxic elements (PTEs), other particulates and emissions during the heat treatment of e-waste using alumina adsorbents. Waste PCBs from mobile phones were mechanically crushed to sizes less than 1mm; their thermal degradation was investigated using thermo-gravimetric analysis. Observed weight loss was attributed to the degradation of polymers and the vaporization of organic constituents and volatile metals. The sample assembly containing PCB powder and adsorbent was heat treated at 600°C for times ranging between 10 and 30min with air, nitrogen and argon as carrier gases. Weight gains up to ∼17% were recorded in the adsorbent thereby indicating the capture of significant amounts of particulates. The highest level of adsorption was observed in N2 atmosphere for small particle sizes of alumina. SEM/EDS results on the adsorbent indicated the presence of Cu, Pb, Si, Mg and C. These studies were supplemented with ICP-OES analysis to determine the extent of various species captured as a function of operating parameters. This innovative, low-cost approach has the potential for utilization in the informal sector and/or developing countries, and could play a significant role in reducing toxic emissions from e-waste processing towards environmentally safe limits.


Subject(s)
Air Pollution/prevention & control , Electronic Waste , Refuse Disposal/methods , Adsorption , Atmosphere , Hot Temperature , Incineration , Temperature
8.
Anal Chem ; 88(18): 9071-8, 2016 09 20.
Article in English | MEDLINE | ID: mdl-27530906

ABSTRACT

Detection of ultratrace levels of aqueous uranyl ions without using sophisticated analytical instrumentation and a tedious sample preparation method is a challenge for environmental monitoring and mitigation. Here we present a novel yet simple analytical method for highly sensitive and specific detection of uranyl ions via photoluminescence quenching of CdS quantum dots. We have demonstrated a new approach for synthesizing highly water-soluble and strong photoluminescence-emitting CdS quantum dots (i.e., CdS-MAA and CdS-MAA-TU) of sizes less than 3 nm. The structural, morphological, and optical properties of both the batches of CdS quantum dots were thoroughly characterized by XRD, high-resolution transmission electron microscopy (HRTEM), zeta potential, UV-visible absorption, and photoluminescence spectroscopy. Compared to the batch of CdS quantum dots prepared by capping with only mercaptoacetic acid (CdS-MAA), the batch prepared by capping with mercaptoacetic acid and thiourea in tandem (CdS-MAA-TU) exhibited higher quantum yield= 16.64 ± 1.02%, and more importantly, CdS-MAA-TU exhibited significantly a higher order of photoluminescence quenching responses when treated with ultratrace concentrations of uranyl ions. Under the optimized conditions, the sensitivity of detecting uranyl ion by CdS-MAA-TU was several folds better (0.316 L/ µg) than that of CdS-MAA (0.0053 (L/µg/), as determined from their respective Stern-Volmer plots. Qualitatively, CdS-MAA-TU probe can be used for visual detection of uranyl ions of concentration greater than 5 µg/L. However, the instrumental method of analysis based on photoluminescence spectroscopy confirmed the feasibility for quantitative analysis of ultratrace concentrations of uranyl ions as implied from a very low limit of detection (LoD = 0.07 µg/L) and limit of quantification (LoQ = and 0.231 µg/L). Systematic studies revealed very high selectivity for uranyl ion detection, though minor interference from Cu(2+), Pb(2+), Hg(2+), CO3(2-), and SO4(2-) was found. The recovery analysis performed by spiking uranyl ions (0.5 µg/L to 10.0 µg/L) in groundwater and river water samples, confirmed the robustness of the as-developed CdS-MAA-TU QDs for detecting ultratrace levels of uranyl ions in real water sample matrix. The very simple and effective strategy reported here should facilitate developing reliable sensors for detecting uranyl ion contamination in drinking water.

9.
Article in English | MEDLINE | ID: mdl-23485236

ABSTRACT

The toxicity effect due to chronic exposure of ZnO nanoparticles (NPs) was systematically studied by repeatedly treating different lower concentrations of ZnO nanoparticles with culture media of E. coli strain. The chronic exposure of ZnO NPs of concentrations below minimum inhibitory concentration (MIC) exhibited higher toxicity than the single exposure of higher concentrations. Most striking result was 57% inhibition of growth corresponding to chronic exposure of 0.06 mg/mL of ZnO NPs which was two folds more than that exhibited by single exposure of 0.30 mg/mL ZnO NPs. The toxicity of ZnO NPs in E. coli was studied in the light of formation of reactive oxygen species (ROS), measured as malondialdehyde (MDA) equivalent by thiobarbituric acid-ROS (TBARS) assay, and effect of Zn dissolution from ZnO NPs. Higher inhibition of growth for the chronic exposure batches were correlated with higher ROS generation, which subsequently contributed to cause membrane lipid peroxidation, confirmed from observation of cell wall deformation by scanning electron microscopy study and energy dispersive X-ray analysis showed adherence of ZnO NPs on cell wall. The possibility of membrane lipid peroxidation was addressed by revealing in vitro oxidation of oleic acid, which is a monounsaturated fatty acid. Further in this study we have shown that the dissolution of ZnO NPs at pH 7.4 was not significant to cause Zn-induced toxicity.


Subject(s)
Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/toxicity , Escherichia coli/drug effects , Metal Nanoparticles/toxicity , Zinc Oxide/pharmacology , Zinc Oxide/toxicity , Dose-Response Relationship, Drug , Escherichia coli/metabolism , Hydrogen-Ion Concentration , Lipid Peroxidation , Malondialdehyde/metabolism , Microbial Sensitivity Tests , Microscopy, Electron, Scanning , Oleic Acid , Reactive Oxygen Species/metabolism , Thiobarbituric Acid Reactive Substances/metabolism , Toxicity Tests, Chronic
10.
Colloids Surf B Biointerfaces ; 94: 143-50, 2012 Jun 01.
Article in English | MEDLINE | ID: mdl-22348987

ABSTRACT

Recent studies indicated the role of ROS toward antibacterial activity. In our study we report ROS mediated membrane lipid oxidation of Escherichia coli treated with ZnO nanoparticles (NPs) as supported by detection and spectrophotometric measurement of malondialdehyde (MDA) by TBARS (thiobarbituric acid-reactive species) assay. The antibacterial effects of ZnO NPs were studied by measuring the growth curve of E. coli, which showed concentration dependent bacteriostatic and bacteriocidal effects of ZnO NPs. The antibacterial effects were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Further, antibacterial effect of ZnO NPs was found to decrease by introducing histidine to the culture medium treated with ZnO NPs. The ROS scavenging action of histidine was confirmed by treating histidine to the batch of Escherichia coli+ZnO NPs at the end of the lag phase of the growth curve (Set-I) and during inoculation (Set-II). A moderate bacteriostatic effect (lag in the E. coli growth) was observed in Set-II batch while Set-I showed no bacteriostatic effect. From these evidences we confirmed that the antibacterial effect of bare as well as TG capped ZnO NPs were due to membrane lipid peroxidation caused by the ROS generated during ZnO NPs interaction in culture medium.


Subject(s)
Escherichia coli/drug effects , Metal Nanoparticles/chemistry , Reactive Oxygen Species/metabolism , Zinc Oxide/chemistry , Anti-Bacterial Agents , Antioxidants/pharmacology , Culture Media , Dose-Response Relationship, Drug , Escherichia coli/growth & development , Escherichia coli/ultrastructure , Histidine/pharmacology , Lipid Peroxidation/drug effects , Malondialdehyde/analysis , Metal Nanoparticles/ultrastructure , Microscopy, Electron, Transmission , Zinc Oxide/pharmacology
11.
J Environ Sci Health B ; 45(2): 174-81, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20390948

ABSTRACT

Heavy metal distribution in medicinal plants is gaining importance not only as an alternative medicine, but also for possible concern due to effects of metal toxicity. The present study has been focused on emphasizing the heavy metal status and bioaccumulation factors of V, Mn, Fe, Co, Cu, Zn, Se (essential metals) and Cr, Ni, Cd, As and Pb (potentially toxic metals) in medicinal plants grown under two different environmental conditions e.g., near to Khetri copper mine and those in fertile soils of Haridwar, both in India, using Instrumental Neutron Activation Analysis (relative method) and Atomic Absorption Spectrometry. The copper levels in the medicinal plants from Khetri were found to be 3-4 folds higher (31.6-76.5 mg kg(-1)) than those from Haridwar samples (7.40-15.3 mg kg(-1)), which is correlated with very high copper levels (763 mg kg(-1)) in Khetri soil. Among various heavy metals, Cr (2.60-5.92 mg kg(-1)), Cd (1.47-2.97 mg kg(-1)) and Pb (3.97-6.63 mg kg(-1)) are also higher in concentration in the medicinal plants from Khetri. The essential metals like Mn (36.4-69.3 mg kg(-1)), Fe (192-601 mg kg(-1)), Zn (24.9-49.9 mg kg(-1)) and Se (0.13-0.91 mg kg(-1)) and potentially toxic metals like Ni (3.09-9.01 mg kg(-1)) and As (0.41-2.09 mg kg(-1)) did not show much variations in concentration in the medicinal plants from both Khetri and Haridwar. The medicinal plants from Khetri, e.g., Ocimum sanctum, Cassia fistula, Withania somnifera and Azadirachta Indica were found rich in Ca and Mg contents while Aloe barbadensis showed moderately high Ca and Mg. Higher levels of Ca-Mg were found to correlate with Zn (except Azadirachta Indica). The bioaccumulation factors (BAFS) of the heavy metals were estimated to understand the soil-to-plant transfer pattern of the heavy metals. Significantly lower BAF values of Cu and Cr were found in the medicinal plants from Khetri, indicating majority fraction of these metals are precipitated and were immobilized species unsuitable for plant uptake. Overall, Withania somnifera (Ashwagandha) showed very high metal bioaccumulation.


Subject(s)
Copper/analysis , Plants, Medicinal/chemistry , Soil/analysis , India , Mining , Soil Pollutants/analysis
12.
Pak J Biol Sci ; 12(5): 406-12, 2009 Mar 01.
Article in English | MEDLINE | ID: mdl-19579979

ABSTRACT

The effect of salinity on morphological characters of salt tolerant genotypes PVSB9, PVSB19, PNR381, PNR519, Iratom24 and salt sensitive genotype NS15 along with one standard check salt tolerant rice cultivar Pokkali were assessed in two factors Completely Randomized Design with four replications. Seven rice genotypes in combination with six levels of salinity (0, 3, 6, 9, 12 and 15 dS m(-1)) were randomly assigned in 168 experimental plastic pots. The different morphological characters studied include plant height, total number of tillers, Root Dry Weight (RDW), Shoot Dry Weight (SDW) and Total Dry Matter (TDM) content of the selected rice genotypes in view to evaluate their response at different salinity levels. The results on the effect of morphological characters indicated that plant height, total tillers, root, shoot and total dry matter were significantly decreased by the application of salinity. The genotypes Pokkali, PVSB9, PVSB19 showed significantly higher values and the lowest value of all these characters were recorded in NS15. A sharp decrease in percent relative-plant height, RDW, SDW, TDM, total tillers were found in susceptible genotype NS 15 after 3 dS m(-1) level of salinity, but these characters were found to decrease slowly in tolerant genotypes.


Subject(s)
Oryza/genetics , Oryza/physiology , Salt Tolerance/genetics , Genotype , Oryza/anatomy & histology , Plant Roots/anatomy & histology , Plant Shoots/anatomy & histology , Random Allocation , Salinity
13.
J Hazard Mater ; 141(3): 834-41, 2007 Mar 22.
Article in English | MEDLINE | ID: mdl-16956716

ABSTRACT

A traditional method for removal of iron from ground water by using ash has been systematically investigated. Ashes from five different sources, viz., banana rind, banana pseudostem, banana leaf, rice husk and bamboo has been studied. The principle applied is enhanced precipitation of iron at high pH caused by ash. The study included laboratory analysis of some relevant chemical parameters of the ashes and the efficiency of the ashes in removing iron from prefabricated water with respect to quantity of ash and corresponding increase in pH of water. The ash of banana pseudostem has been found to be most suitable for removal of iron. A low-cost and easily made iron removal system for household use has been designed and tested in the laboratory. The ash of banana pseudostem has been found to remove iron to below 0.3ppm without increasing the pH above the acceptable limit. The optimum values of the different parameters for removal of iron are 200-300mgl(-1) ash, 1.0lh(-1) flow rate and 1h of contact time with ash for groundwater having [Fe] of about 2.20ppm. The amount of ash can be increased for groundwater having higher [Fe] and can be decreased gradually during continuous use of the system. Acceptability of the method has been examined based on chemical analysis of the treated water. Increase in the essential minerals such as Ca, K has been observed in the water after treatment. The designed iron removing system is expected to be suitable for household use.


Subject(s)
Iron/isolation & purification , Musa , Water Pollutants, Chemical/isolation & purification , Water Purification/methods , Bambusa , Hot Temperature , Hydrogen-Ion Concentration , Iron/chemistry , Oryza , Plant Stems , Water Pollutants, Chemical/chemistry , Water Supply
14.
Cell Mol Biol (Noisy-le-grand) ; 50 Online Pub: OL609-15, 2004.
Article in English | MEDLINE | ID: mdl-15579254

ABSTRACT

The ionic channels (particularly, K+ and Ca2+ channels) regulate, via the membrane potential, the ionic distribution into the vascular cells. Micro-particule induced X-ray emission (PIXE) analysis was applied to determine the ionic composition of vascular smooth muscle cells (VSMCs) and of vascular endothelial cells (VECs) in the placental human allantochorial vessels in a physiological medium (Hanks' solution) modified by the addition of a NO donor (sodium nitroprusside, SNP) and of a beta-adrenergic stimulator (isoproterenol, ISO). The addition of SNP or ISO induced no modification of the Na, K, Cl, P, S, Mg and Ca concentrations in VSMCs. In VECs, a same effect was observed except an increase of the Mg concentration with ISO. Theses results indicated a retroactive control (active feedback) of the internal ionic distribution by endothelial factors, ionic channels and exchangers.


Subject(s)
Chorioallantoic Membrane/chemistry , Endothelium, Vascular/chemistry , Ions/analysis , Isoproterenol/pharmacology , Muscle, Smooth, Vascular/chemistry , Nitroprusside/pharmacology , Placenta/blood supply , Adrenergic beta-Agonists/pharmacology , Electron Probe Microanalysis , Endothelium, Vascular/drug effects , Endothelium, Vascular/metabolism , Female , Humans , Ion Channels/drug effects , Ion Channels/physiology , Ions/metabolism , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth, Vascular/metabolism , Nitric Oxide Donors/pharmacology , Placenta/drug effects , Pregnancy
15.
Cell Mol Biol (Noisy-le-grand) ; 49(4): 487-92, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12899438

ABSTRACT

The membrane potential, a regulator of vascular tone, is a function of the physiological activities of ionic channels (particularly, K+ and Ca2+ channels in these cells). These channels regulate the ionic distribution into these cells. Micro-particule induced X-ray emission (PIXE) analysis was applied to determine the ionic composition of vascular smooth muscle cells (VSMCs) and of vascular endothelial cells (VECs) in the placental human allantochorial vessels in a physiological medium (Hanks'solution) modified by the addition of a chemical stimulus: 5-hydroxytryptamine (5-HT), an activator of the voltage-sensitive Ca2+ channels. In VSMCs (media layer), the addition of 5-HT induced no modification of the Na, K, Cl, P, S and Ca concentrations but increased Mg concentration. In endothelium (VECs) 5-HT addition implicated an increase of the K, S, Ca concentrations, the concentration of the other ions remained constant. In VECs, Ca and K increase is due to open of L-type voltage-dependent Ca2+ channels and of K(Ca) channels. 5-HT induces also a secretion of endothelium hyperpolarizing factors which implicate decrease of [Ca2+]i in VSMCs opposite to a direct increase by 5-HT. Increase in [Mg2+]i may be due to activation of the Ca/Mg exchanger.


Subject(s)
Blood Vessels/metabolism , Ions/metabolism , Serotonin/metabolism , Allantois/blood supply , Chorion/blood supply , Endothelium, Vascular/metabolism , Humans , Muscle, Smooth, Vascular/metabolism , Placenta/blood supply , Placenta/metabolism
16.
Talanta ; 55(2): 233-40, 2001 Aug 30.
Article in English | MEDLINE | ID: mdl-18968365

ABSTRACT

Organic ligand with carboxyhydrazide functional group was immobilised on the surface of silica gel and the metal binding capacity of the ligand-embedded silica was investigated. The functional group was covalently bonded to the silica matrix through a spacer of methylene groups by sequential reactions of silica gel with dibromobutane, malonic ester and hydrazine in different media. Surface area value of the modified silica was determined. The changes in surface area were correlated with the structural change of the silica surface due to chemical modifications. A mixture solution of metal ions [K(I),Cr(III),Co(II),Ni(II),Cu(II),Zn(II),Hg(II) and U(VI)] was treated with the ligand-embedded silica in 10(-3) M aqueous solution. The measurement of metal extraction capacity of the silica based ligand was done by multielemental analysis of the metal complexes thus formed by using Proton Induced X-ray Emission (PIXE) technique.

17.
J Basic Microbiol ; 32(3): 167-76, 1992.
Article in English | MEDLINE | ID: mdl-1512707

ABSTRACT

Plasmid-harbouring, sterol-decomposing organism Arthrobacter oxydans 317 was treated with sodium dodecylsulphate to obtain a plasmid-cured strain A. oxydans 317 A1 incapable of utilizing 4-androstene-3,17-dione (AD). The strain 317 A1 was unable to degrade beta-sitosterol side chain completely to form AD but could carry out partial degradation as shown by the accumulation of 3-oxochol-4-en-24-oic acid as a major metabolite and 27-norcholest-4-en-3,24-dione as a minor metabolite. The strain could form 1,4-androstadiene-3,17-dione (ADD) from 3-oxo-23,24-bisnorchol-1,4-dien-22- oic acid (BNC) to a limited extent. The existence of metabolic blocks in the conversion of 3-oxochol-4-en-24-oic acid to 3-oxo-23,24-bis-norchol-4-en-22-oic acid and further conversion to AD by the plasmid-cured strain 317 A1 was suggested. Neither the formation of ADD from AD nor the conversion of AD and ADD to 9 alpha-hydroxy derivatives leading to steroid ring opening could be done by the plasmid-cured strain but the 17 beta-reduction of AD and ADD and 1(2)-reduction of ADD were not affected by the absence of the plasmid. It was proposed that plasmid determines 1(2)-dehydrogenation and 9 alpha-hydroxylation of steroid ring structure in this organism.


Subject(s)
Arthrobacter/metabolism , Plasmids , Sitosterols/metabolism , Androstadienes/metabolism , Androstenedione/metabolism , Arthrobacter/genetics , Biodegradation, Environmental , Cholestenones/metabolism , Species Specificity
18.
Indian J Lepr ; 62(4): 429-34, 1990.
Article in English | MEDLINE | ID: mdl-2086677

ABSTRACT

100 leprosy patients were studied for audiovestibular involvement. Conductive hearing loss was detected in 6 cases of BT leprosy, all of them having coincidental chronic middle ear infection. Sensori-neural hearing loss was detected in 10 cases, of which 6 had LL, 2 BT and 2 pure neuritic type of disease respectively. All the cases of lepromatous leprosy having sensorineural hearing loss had evidence of ENL reaction. Vestibular involvement was not detected in any of the cases. Evaluation of audiovestibular function was also carried out in 50 fresh cases of leprosy and after 3 months, 6 months and 1 year of multidrug therapy to ascertain any ototoxic side effects of antileprosy drugs. No audiovestibular dysfunction was detected in these patients at any time during follow-up.


Subject(s)
Leprosy/physiopathology , Adult , Audiometry, Pure-Tone , Evaluation Studies as Topic , Female , Hearing Loss, Conductive/complications , Hearing Loss, Conductive/physiopathology , Hearing Loss, Sensorineural/physiopathology , Humans , Leprostatic Agents/adverse effects , Leprosy/complications , Leprosy, Borderline/complications , Leprosy, Borderline/physiopathology , Leprosy, Lepromatous/complications , Leprosy, Lepromatous/physiopathology , Leprosy, Tuberculoid/complications , Leprosy, Tuberculoid/physiopathology , Male , Middle Aged , Nystagmus, Physiologic , Otitis Media, Suppurative/complications , Otitis Media, Suppurative/physiopathology , Vestibular Function Tests
19.
Indian J Lepr ; 60(1): 71-6, 1988 Jan.
Article in English | MEDLINE | ID: mdl-3204277

ABSTRACT

Fifty eight cases including 44 paucibacillary and 14 multibacillary leprosy diagnosed at Command Hospital SC Pune were hospitalised for the entire period of multidrug therapy. 76% cases belonged to high endemic states of India. Reactions occurred in 13 cases during treatment, type I in 10 and type II in three. 7 Multibacillary cases experienced reaction. 69% reaction patients developed reaction within two months of starting MDT and all of them were multibacillary. Usually it took 3-6 months for majority (61.5%) of reactions subside completely. In 65.5% paucibacillary patients activity subsided within twelve months, however 70.5% paucibacillary cases took more than six months to exhibit subsidence of activity. In 13 multibacillary cases activity subsided by 18 months though bacteriological negativity was obtained from fourth to twelve months.


Subject(s)
Clofazimine/therapeutic use , Dapsone/therapeutic use , Leprosy/drug therapy , Rifampin/therapeutic use , Adult , Drug Resistance, Microbial , Drug Therapy, Combination , Female , Humans , Male
20.
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