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1.
Environ Monit Assess ; 195(6): 762, 2023 May 30.
Article in English | MEDLINE | ID: mdl-37249656

ABSTRACT

As a sequel to our recent study on the oxidation by O2, i. e., autoxidation of dissolved hydrogen sulfide, H2S, in aqueous medium, we present here the results of a similar study in rain water medium. The rainwater sampling was done sequentially for four years (2016-2019). In all 67 samples of rainwater were collected on event basis during monsoon period (June-October) in and around the Campus of University of Rajasthan, Jaipur (26°50̛ N-75°52̛ E), which is situated in a semi-arid region adjacent to the Thar Desert in the North-Western part of the India having an annual average rainfall of 54 cm. ICP-MS technique was used in the analysis of rainwater and more than 30 metals were detected, which included transition metals, rare earths, less common metals. Beryllium, vanadium, silver, selenium, manganese, cerium, gallium, yttrium, barium, cesium, copper, rubidium, arsenic, lanthanum, cadmium, lead, uranium and bismuth were common to all rain water samples.H2S oxidation by dissolved oxygen was studied in rainwater as well as in laboratory water media for comparison. The kinetics rate law was: -d[O2]/dt = k1K1[H+][S][O2]t/( [H+]2 + K1[H+] + K1K2), where K1 is first dissociation constant of H2S and k1 is the rate constant for the dominant reaction step:HS- + O2 → products.


Subject(s)
Hydrogen Sulfide , Metals, Heavy , Hydrogen Sulfide/analysis , Oxygen/analysis , Kinetics , Environmental Monitoring , Silver/analysis , Rain , Water/analysis , Metals, Heavy/analysis
2.
Natl J Maxillofac Surg ; 13(Suppl 1): S153-S158, 2022 Aug.
Article in English | MEDLINE | ID: mdl-36393958

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 infection has resulted in a pandemic, the disease manifests itself as various conditions ranging from respiratory disorders to exacerbated inflammatory responses. The management in some cases involves immediate care in an intensive setup with the administration of various antibiotics and steroids which has resulted in the imposition of risk factors and growth of fulminant fungal infection. The present article addresses two such cases which presented with osteomyelitis secondary to mucormycosis in patients who had more than one episode of COVID-19 infection. The upsurge of existing manifestation and development of opportunistic infections has to be considered in patients who are suffering or recovering from COVID-19. The COVID-19 scenario brings up a possibility of many bacterial and fungal infections in its aftermath. This article brings out two such opportunistic aggressive fungal infections and comprehensive management of the same.

3.
J Toxicol ; 2019: 7898914, 2019.
Article in English | MEDLINE | ID: mdl-30774656

ABSTRACT

Terminalia tomentosa bark belongs to the family Combretaceae. The plant bark is astringent and useful in the treatment of ulcers, vata, fractures, hemorrhages, bronchitis, and diarrhea. Phytochemical investigation of T. tomentosa bark confirms the presence of flavonoids, polyphenols, and tannins. The plant has not been investigated for its anti-inflammatory and antiarthritic activity. The present study was undertaken to explore its possible anti-inflammatory and antiarthritic activity. Anti-inflammatory activity of alcoholic and aqueous extracts of the bark was assessed by in vivo methods. In vivo antiarthritic potential of the extracts was evaluated by Complete Freund's Adjuvant (CFA) induced arthritis in Wistar rats. Our findings showed that the alcoholic and aqueous extracts exhibited anti-inflammatory activity at 500 mg/kg oral dose in carrageenan-induced hind paw edema and carrageenan-induced air pouch inflammation models. We also found alcoholic as well as aqueous extracts of the bark restored the altered blood and serum parameters caused by the Complete Freund's Adjuvant-induced arthritis in Wistar rats. This study shows that the T. tomentosa bark extracts possess anti-inflammatory activity and have pronounced effects on adjuvant arthritis also. Future studies are necessary to provide deeper insight into the exact mechanism of the action of anti-inflammatory and antiarthritic activity of T. tomentosa.

5.
J Clin Pathol ; 60(9): 1040-7, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17079356

ABSTRACT

AIM: To investigate the complex interplay between human papilloma virus (HPV) infection and p53 gene alteration in 92 head and neck squamous cell carcinoma (HNSCC) and 28 leukoplakia samples from eastern India. METHODS: DNA isolated from the patient samples was subjected to HPV detection, loss of heterozygosity (LOH) analysis of the chromosome 17p region harbouring p53, genotyping at the p53 codon 72 locus and sequencing of the entire p53 gene to identify somatic mutations. Codon 72 heterozygotes carrying the p53 mutation were further cloned and resequenced to identify the allele harbouring the mutation. RESULTS: HPV positivity in the HNSCC samples was 69%; 21% of the HNSCC were found to harbour p53 mutations in the coding region of the gene. The absence of the p53 mutation in HPV positive tumours was statistically significant compared to the HPV negative tumours (p = 0.01), but the same did not hold true for p53 LOH (p = 1.0). Among the germline p53 codon 72 heterozygotes, the Pro allele was preferentially lost (p = 0.02) while the Arg allele was mutated in the majority of cases. The risk of HPV mediated tumourigenesis increased with the increase in number of Arg alleles at the codon 72 locus. CONCLUSION: It is proposed that genetic and epigenetic alteration of p53 follow distinct pathways during the development of HNSCC from normal epithelium via dysplasia. The p53 mutation and HPV mediated p53 inactivation possibly constitute two independent pathways of tumourigenesis.


Subject(s)
Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/virology , Genes, p53 , Head and Neck Neoplasms/genetics , Head and Neck Neoplasms/virology , Papillomavirus Infections/complications , Adult , Carcinoma, Squamous Cell/pathology , Cell Transformation, Neoplastic/genetics , Chromosomes, Human, Pair 17/genetics , Female , Gene Silencing , Head and Neck Neoplasms/pathology , Humans , Leukoplakia, Oral/genetics , Leukoplakia, Oral/virology , Loss of Heterozygosity , Male , Middle Aged , Mutation , Papillomaviridae/classification , Papillomaviridae/isolation & purification , Papillomavirus Infections/virology
7.
Fish Shellfish Immunol ; 20(5): 728-38, 2006 May.
Article in English | MEDLINE | ID: mdl-16293422

ABSTRACT

The purpose of this study was to determine if injections of different dosages of tuftsin would enhance the immune response and disease resistance against the infections due to the opportunistic pathogens Aeromonas hydrophila and Edwardsiella tarda in Labeo rohita fingerlings. Hence, four different dosages of tuftsin in PBS suspension at the rate of 0, 5, 10, 15 mg kg(-1) body weight of fish were injected intraperitoneally to the fingerlings of L. rohita at 2-week intervals for four times. After every 2-week interval, different serum biochemical, haematological and immunological parameters of fish were evaluated. Biochemical and haematological parameters including serum total protein content, albumin content, globulin content, albulin:globulin ratio, glucose content, leucocyte counts etc.; cellular immune parameters including superoxide anion production, phagocytic activities, lymphokine production index etc.; humoral immune parameters including lysozyme activity, complement activity, serum bactericidal activity etc., in the fish were evaluated after every 2-week interval. After 56 days, fish were divided into two subgroups under each major treatment group for challenge with two pathogens A. hydrophila and E. tarda. The mortality (%) and agglutinating antibody titre was recorded on 28th day post challenge. Most of the immune parameters including leucocyte count, phagocytic ratio, phagocytic index, lysozyme activity, complement activity, and serum bactericidal activity were significantly (p

Subject(s)
Carps/immunology , Fish Diseases/prevention & control , Immunity, Innate/drug effects , Immunologic Factors/pharmacology , Tuftsin/pharmacology , Aeromonas hydrophila/immunology , Agglutination Tests , Animals , Blood Glucose/analysis , Blood Proteins/analysis , Complement System Proteins/metabolism , Edwardsiella tarda/immunology , Enterobacteriaceae Infections/mortality , Enterobacteriaceae Infections/prevention & control , Enterobacteriaceae Infections/veterinary , Fish Diseases/mortality , Gram-Negative Bacterial Infections/mortality , Gram-Negative Bacterial Infections/prevention & control , Gram-Negative Bacterial Infections/veterinary , Injections, Intraperitoneal/veterinary , Leukocyte Count/veterinary , Lymphokines/biosynthesis , Muramidase/metabolism , Phagocytosis/drug effects , Serum Bactericidal Test/methods , Superoxides/analysis , Superoxides/metabolism , Time Factors
8.
J Clin Pathol ; 58(1): 26-31, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15623478

ABSTRACT

BACKGROUND: The predictive value of codon 72 arginine homozygosity at the p53 gene for human papilloma virus associated cervical cancer risk remains inconclusive. It has also been proposed that the inheritance of specific germline haplotypes based on three biallelic polymorphisms of p53 (intron 3 16 bp duplication, codon 72 Bst UI (Arg/Pro), and intron 6 Nci I restriction fragment length polymorphism at nucleotide 13494) is a better predictor of various cancer risks. AIMS: To determine the genotype and haplotype frequency of these three p53 polymorphisms in 61 patients with cervical squamous cell carcinoma and 94 ethnically matched controls from the eastern region of India and estimate the risk, if any, of specific genotypes and haplotypes. METHODS: Samples were genotyped by polymerase chain reaction followed by variant specific restriction enzyme digestion. Haplotypes were estimated by the maximum likelihood method using the expectation maximisation algorithm. RESULTS: Genotype distributions of the three polymorphisms in patients and controls showed a good fit to the Hardy-Weinberg equilibrium. The p53 codon 72 arginine homozygous genotype was significantly over represented in patients compared with controls. Those with the homozygous arginine genotype exhibited a 2.59 fold higher risk of developing squamous cell carcinoma of the uterine cervix. A significant risk was also seen with a combination of two haplotypes, 1-2-1 and 1-2-2. CONCLUSION: p53 codon 72 arginine homozygotes appear to be at greater risk of developing squamous cell carcinoma of the uterine cervix. The high risk haplotypes 1-2-1 and 1-2-2 also contain the arginine allele, further strengthening this conclusion.


Subject(s)
Carcinoma, Squamous Cell/genetics , Genes, p53/genetics , Genetic Predisposition to Disease , Uterine Cervical Neoplasms/genetics , Adult , Arginine/genetics , Carcinoma, Squamous Cell/pathology , Carcinoma, Squamous Cell/virology , Female , Genotype , Haplotypes , Humans , Middle Aged , Neoplasm Staging , Papillomaviridae/classification , Papillomaviridae/isolation & purification , Polymorphism, Genetic , Uterine Cervical Neoplasms/pathology , Uterine Cervical Neoplasms/virology
9.
Neurotoxicology ; 26(1): 133-40, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15527881

ABSTRACT

The etiology of neurodegenerative disorders is at present unknown. However, many of these disorders are associated with an increase in oxidative and inflammatory events. Although a small percentage of these disorders are familial cases linked to specific genetic defects, most are idiopathic. Thus, environmental factors are thought to play an important role in the onset and progression of such disorders. We have demonstrated that exposure (4 h, 5 days per week for 2 weeks) to concentrated airborne particulate matter increases inflammatory indices in brain of ovalbumin-sensitized BALB/c mice. Animals were divided into three exposure groups: filtered air (control), ultrafine particles, or fine and ultrafine particles. The levels of proinflammatory cytokines interleukin-1 alpha (IL-1alpha) and tumor necrosis factor alpha (TNF-alpha) were increased in brain tissue of mice exposed to particulate matter compared to that of control animals. Levels of the immune-related transcription factor NF-kappaB were also found to be substantially elevated in the brain of exposed groups compared with the control group. These data indicate that components of inhaled particulate matter may trigger a proinflammatory response in nervous tissue that could contribute to the pathophysiology of neurodegenerative diseases.


Subject(s)
Air Pollutants/toxicity , Encephalitis/chemically induced , Encephalitis/metabolism , Air Pollutants/chemistry , Animals , Antigens/immunology , Asthma/chemically induced , Asthma/pathology , Biomarkers , Brain/pathology , Chemical Phenomena , Chemistry, Physical , Electrophoretic Mobility Shift Assay , Enzyme-Linked Immunosorbent Assay , Interleukin-1/biosynthesis , Lipopolysaccharides/toxicity , Male , Mice , Mice, Inbred BALB C , NF-kappa B/metabolism , Neurodegenerative Diseases/chemically induced , Neurodegenerative Diseases/pathology , Ovalbumin/immunology , Particle Size , Tumor Necrosis Factor-alpha/biosynthesis
10.
J Air Waste Manag Assoc ; 51(9): 1309-17, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11575884

ABSTRACT

In this paper, we describe the development and laboratory and field evaluation of a continuous coarse (2.5-10 microm) particle mass (PM) monitor that can provide reliable measurements of the coarse mass (CM) concentrations in time intervals as short as 5-10 min. The operating principle of the monitor is based on enriching CM concentrations by a factor of approximately 25 by means of a 2.5-microm cut point round nozzle virtual impactor while maintaining fine mass (FM)--that is, the mass of PM2.5 at ambient concentrations. The aerosol mixture is subsequently drawn through a standard tapered element oscillating microbalance (TEOM), the response of which is dominated by the contributions of the CM, due to concentration enrichment. Findings from the field study ascertain that a TEOM coupled with a PM10 inlet followed by a 2.5-microm cut point round nozzle virtual impactor can be used successfully for continuous CM concentration measurements. The average concentration-enriched CM concentrations measured by the TEOM were 26-27 times higher than those measured by the time-integrated PM10 samplers [the micro-orifice uniform deposit impactor (MOUDI) and the Partisol] and were highly correlated. CM concentrations measured by the concentration-enriched TEOM were independent of the ambient FM-to-CM concentration ratio, due to the decrease in ambient coarse particle mass median diameter with an increasing FM-to-CM concentration ratio. Finally, our results illustrate one of the main problems associated with the use of real impactors to sample particles at relative humidity (RH) values less than 40%. While PM10 concentrations obtained by means of the MOUDI and Partisol were in excellent agreement, CM concentrations measured by the MOUDI were low by 20%, and FM concentrations were high by a factor of 5, together suggesting particle bounce at low RH.


Subject(s)
Air Pollution/analysis , Environmental Monitoring/instrumentation , Cities , Equipment Design , Particle Size , Sensitivity and Specificity , Time Factors
11.
Water Res ; 35(1): 160-6, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11257870

ABSTRACT

The present study was initiated to explore the potential of a hybrid biological reactor, combining trickling filter (TF) and activated sludge process (ASP), to treat wastewater containing trichloroethylene (TCE) at ambient temperature at different hydraulic retention time (HRT). The biofilm acclimation was achieved in 55-60 days with gradual increase in TCE concentration from 1 mg/l to 100 mg/l with a parallel increase in the concentration of substrate sodium acetate and other nutrients. COD and TCE concentration were taken as prime parameters for monitoring the growth of biofilm. During acclimation COD removal varied between 54.6-97.5% while TCE was removed 72.6-99.9%. HRT study was performed after acclimation. The removal efficiency increased with decreasing flow rate with maximum TCE removal (99.99%) at 6 l/d corresponding to an HRT of 28 h (TF 18 h + ASP 10 h). This was followed by a C:N:P ratio study. A ratio of 100:20:1 led to the sustenance of maximum TCE removal. Maximum TCE removal (99.99%) was observed at a substrate:cosubstrate ratio of 100:1. A pH of 7.4 +/- 0.2 was found to be optimum for degradation. Finally, volatilization losses were estimated to be 18.5%. A mass balance gave an efficiency of 81.51% for biological removal of TCE.


Subject(s)
Trichloroethylene/isolation & purification , Waste Disposal, Fluid , Water Pollutants, Chemical/isolation & purification , Water Purification/instrumentation , Water Purification/methods , Biodegradation, Environmental , Equipment Design , Filtration , Sodium Acetate/analysis
12.
J Neurosci ; 20(16): 5899-905, 2000 Aug 15.
Article in English | MEDLINE | ID: mdl-10934236

ABSTRACT

During cerebellar development, granule cells display well characterized changes in the expression of NMDA receptor (NMDAR) NR2 subunits, switching from NR2B to NR2A and NR2C in mature cells. Although various studies, including experiments on mutant mice with one or more NR2 subunit types deleted, suggest that NR2A, NR2B, and NR2C subunits contribute to synaptic NMDARs, changes in the properties of the mossy fiber EPSC during development have not been fully evaluated. In particular, information on NMDAR EPSCs in mature animals is lacking. We have examined pharmacological and kinetic properties of NMDARs at mossy fiber-granule cell synapses from their formation to maturity [postnatal day 7 (P7)-P40 rats]. Significant changes were seen in the relative amplitudes of the non-NMDAR- and NMDAR-mediated components of the evoked EPSC and in the decay kinetics of the latter. The NMDA/non-NMDA ratio was similar at P7, P21, and P40, but showed a clear peak at P12. This change coincided with a speeding of the NMDAR EPSC decay, accompanied by a decrease in sensitivity to ifenprodil (selective NR2B-antagonist). By P21, sensitivity of the NMDAR EPSC to Mg(2+) was approximately threefold less than that at P12 (IC(50), 76 vs 28 microm), suggesting incorporation of the NR2C subunit. However, the predicted slowing of decay kinetics to a value more characteristic of NR2C deactivation, was not seen until P40. Our data are consistent with the known switch from NR2B to NR2A subunits during the first two postnatal weeks, but suggest a gradual incorporation of the NR2C subunit that modifies Mg(2+) sensitivity and only later influences EPSC kinetics.


Subject(s)
Cerebellum/growth & development , Nerve Fibers/metabolism , Receptors, N-Methyl-D-Aspartate/metabolism , Synapses/metabolism , Age Factors , Animals , Cerebellum/metabolism , Cerebellum/ultrastructure , Excitatory Amino Acid Antagonists/pharmacology , Excitatory Postsynaptic Potentials/drug effects , Excitatory Postsynaptic Potentials/physiology , In Vitro Techniques , Kinetics , Magnesium/metabolism , Magnesium/pharmacology , Nerve Fibers/ultrastructure , Piperidines/pharmacology , Rats , Rats, Sprague-Dawley , Receptors, N-Methyl-D-Aspartate/drug effects , Synapses/ultrastructure , Synaptic Transmission/drug effects , Synaptic Transmission/physiology
13.
J Physiol ; 525 Pt 2: 299-305, 2000 Jun 01.
Article in English | MEDLINE | ID: mdl-10835034

ABSTRACT

We have examined the deactivation kinetics of native N-methyl-D-aspartate receptors (NMDARs) containing NR1 and NR2D subunits by patch-clamp recording from Purkinje cells in cerebellar slices from young rats. NMDAR-mediated whole-cell currents were elicited in response to bath application of 20 microM NMDA and 50 microM glycine. The NMDAR-mediated currents were small, with an average whole-cell conductance of approximately 750 pS. Following the rapid application of brief pulses (1-10 ms) of 1 mM glutamate to outside-out membrane patches, we observed a low-conductance type of single-channel activity which lasted up to 30 s after the removal of agonist. Analysis of individual channel openings revealed asymmetry of transitions between the main- and subconductance states - a characteristic of NR1/NR2D-containing NMDARs. The averaged macroscopic current exhibited a decay time course which was well described by a single exponential function with a time constant of approximately 3 s. We conclude that native NR1/NR2D-containing NMDARs, like their recombinant counterparts, display very slow deactivation kinetics. This feature should provide a means for identification of these receptors at synapses, and indicates that they do not contribute to the synaptic NMDAR currents so far described.


Subject(s)
Purkinje Cells/metabolism , Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors , Receptors, N-Methyl-D-Aspartate/chemistry , Animals , Glutamic Acid/pharmacology , In Vitro Techniques , Kinetics , Patch-Clamp Techniques , Purkinje Cells/drug effects , Rats , Rats, Sprague-Dawley , Receptors, N-Methyl-D-Aspartate/metabolism
14.
J Physiol ; 524 Pt 1: 147-62, 2000 Apr 01.
Article in English | MEDLINE | ID: mdl-10747189

ABSTRACT

1. To investigate the properties of N-methyl-D-aspartate receptors (NMDARs) in cerebellar Golgi cells, patch-clamp recordings were made in cerebellar slices from postnatal day 14 (P14) rats. To verify cell identity, cells were filled with Neurobiotin and examined using confocal microscopy. 2. The NR2B subunit-selective NMDAR antagonist ifenprodil (10 microM) reduced whole-cell NMDA-evoked currents by approximately 80 %. The NMDA-evoked currents were unaffected by the Zn2+ chelator N,N,N',N'-tetrakis-(2-pyridylmethyl)-ethylenediamine (TPEN; 1 microM) suggesting the absence of NMDARs containing NR2A subunits. 3. Outside-out patches from Golgi cells exhibited a population of 'high-conductance' 50 pS NMDAR openings. These were inhibited by ifenprodil, with an IC50 of 19 nM. 4. Patches from these cells also contained 'low-conductance' NMDAR channels, with features characteristic of NR2D subunit-containing receptors. These exhibited a main conductance of 39 pS, with a sub-conductance level of 19 pS, with clear asymmetry of transitions between the two levels. As expected of NR2D-containing receptors, these events were not affected by ifenprodil. 5. The NMDAR-mediated component of EPSCs, evoked by parallel fibre stimulation or occurring spontaneously, was not affected by 1 microM TPEN. However, it was reduced (by approximately 60 %) in the presence of 10 microM ifenprodil, to leave a residual NMDAR-mediated current that exhibited fast decay kinetics. This is, therefore, unlikely to have arisen from receptors composed of NR1/NR2D subunits. 6. We conclude that in cerebellar Golgi cells, the high- and low-conductance NMDAR channels arise from NR2B- and NR2D-containing receptors, respectively. We found no evidence for NR2A-containing receptors in these cells. While NR2B-containing receptors are present in both the synaptic and extrasynaptic membrane, our results indicate that NR1/NR2D receptors do not contribute to the EPSC and appear to be restricted to the extrasynaptic membrane.


Subject(s)
Cerebellum/physiology , Neurons/physiology , Receptors, N-Methyl-D-Aspartate/physiology , Synapses/physiology , 2-Amino-5-phosphonovalerate/pharmacology , Animals , Cerebellum/cytology , Ethylenediamines/pharmacology , Evoked Potentials/drug effects , Excitatory Amino Acid Antagonists/pharmacology , In Vitro Techniques , Microscopy, Confocal , N-Methylaspartate/pharmacology , Neurons/classification , Neurons/cytology , Piperidines/pharmacology , Rats , Rats, Sprague-Dawley , Receptors, N-Methyl-D-Aspartate/drug effects
15.
Neuropharmacology ; 37(10-11): 1369-80, 1998.
Article in English | MEDLINE | ID: mdl-9849672

ABSTRACT

Recent studies of N-methyl-D-aspartate (NMDA) receptors have led to the suggestion that there are two distinct classes of native NMDA receptors, identifiable from their single-channel conductance properties. 'High-conductance' openings arise from NR2A- or NR2B-containing receptors, and 'low-conductance' openings arise from NR2C- or NR2D-containing receptors. In addition, the low-conductance channels show reduced sensitivity to block by Mg2+. The readily identified cell types and simple architecture of the cerebellum make it an ideal model system in which to determine the contribution of specific subunits to functional NMDA receptors. Furthermore, mRNA for all of these four NR2 subunits are represented in this brain region. We have examined NMDA channels in Purkinje cells, deep cerebellar nuclei (DCN) neurons and Golgi cells. First we find that NR2D-containing NMDA receptors give rise to low-conductance openings in cell-attached recordings from Purkinje cells. The characteristic conductance of these events cannot, therefore, be ascribed to patch excision. Second, patches from some DCN neurons exhibit mixed populations of high- and low-conductance openings. Third, Golgi cells also exhibit a mixed population of high- and low-conductance NMDA receptor openings. The features of these low-conductance openings are consistent with the presence of NR2D-containing NMDA receptors, as suggested by in situ hybridization data. On the other hand the existence of high-conductance channels, with properties typical of NR2B-containing receptors, was not expected. Our results provide new evidence about the subunit composition of NMDA receptors in identified cerebellar cells, and suggest that examination of single-channel properties is a potentially powerful approach for determining the possible subunit composition of native NMDA receptors.


Subject(s)
Cerebellum/metabolism , Receptors, N-Methyl-D-Aspartate/metabolism , Animals , Cerebellar Nuclei/metabolism , Cerebellum/cytology , Patch-Clamp Techniques , Purkinje Cells/metabolism , Rats , Rats, Sprague-Dawley
16.
Brain Res ; 737(1-2): 92-8, 1996 Oct 21.
Article in English | MEDLINE | ID: mdl-8930355

ABSTRACT

It has been proposed that nitric oxide (NO) is involved in the spinal transmission of nociceptive information, particularly following the development of peripheral inflammation. In this electrophysiological study the ability of the nitric oxide synthase inhibitor 7-nitro indazole (7-NI), which does not block endothelial nitric oxide in vivo, to inhibit the electrically evoked responses of dorsal horn neurones recorded in both normal animals and in animals 3 h after the injection of carrageenan into the ipsilateral hind paw, was investigated. In both normal and carrageenan inflamed animals, 7-NI (1-100 micrograms), administered intrathecally, strongly inhibited the NMDA receptor mediated wind-up and post-discharge of the neurones, having relatively little effect on the acute C- or A beta-fibre evoked activity of the neurones. This inhibitory action of 7-NI on the noxious evoked responses of the neurones was completely blocked by the prior intrathecal administration of 500 micrograms of L-arginine. Inflammation did not alter the effects of 7-NI since there was no difference in the dose-response curve between the normal and carrageenan animals. In normal animals, stimuli of sufficient duration/intensity to enable the activation of NMDA receptors to occur, shown in this study by the occurrence of wind-up, also lead to the generation of nitric oxide, which then participates in nociceptive transmission. These effects appear to be independent of the vascular effects of NO. Inflammation-induced changes could facilitate activation of spinal NMDA receptors, such that nitric oxide is now generated by stimuli previously sub-threshold for this event. Previous studies, reporting a unique role of NO in nociceptive transmission following the development of peripheral inflammation, may have resulted from inadequate stimuli in the normal animal.


Subject(s)
Nitric Oxide/biosynthesis , Nociceptors/physiology , Spinal Cord/physiology , Animals , Arginine/pharmacology , Blood Pressure/drug effects , Carrageenan , Dose-Response Relationship, Drug , Enzyme Inhibitors/pharmacology , Evoked Potentials/drug effects , Excipients , Indazoles/pharmacology , Injections, Intravenous , Injections, Spinal , Male , Neuritis/chemically induced , Neuritis/physiopathology , Neurons/drug effects , Neurons/metabolism , Nitric Oxide/metabolism , Rats , Rats, Sprague-Dawley , Spinal Cord/cytology , Synaptic Transmission/physiology , Transcutaneous Electric Nerve Stimulation
17.
Vaccine ; 9(12): 865-7, 1991 Dec.
Article in English | MEDLINE | ID: mdl-1811372

ABSTRACT

The efficiency of production of purified Japanese encephalitis (JE) vaccine from mouse brains was increased by reprocessing the brain material after recovery of the virus and by pooling of a few extra fractions after zonal ultracentrifugation. By the routine production method, one mouse yielded approximately 2.5 doses of the vaccine while the improved method gave about five doses from each mouse. All the batches of purified JE vaccine made by improved technology passed all the quality control tests as specified by the Minimum Requirements for biological products of the Japanese Government and World Health Organization.


Subject(s)
Brain/microbiology , Encephalitis Virus, Japanese/immunology , Viral Vaccines , Animals , Centrifugation, Zonal , Encephalitis Virus, Japanese/isolation & purification , Japan , Mice , Vaccines, Inactivated/immunology , Vaccines, Inactivated/standards , Viral Vaccines/immunology , Viral Vaccines/standards , World Health Organization
19.
Indian J Med Res ; 91: 315-20, 1990 Sep.
Article in English | MEDLINE | ID: mdl-2269502

ABSTRACT

The indirect haemagglutination (IHA) test was standardized for the assay of antibodies against Japanese encephalitis (JE) virus. Glutaraldehyde fixed sheep erythrocytes were sensitized with purified and concentrated JE vaccine (200-300% brain concentration). The JE vaccine made from Nakayama-NIH strain of JE virus was purified by protamine sulphate treatment and by ultracentrifugation in a sucrose gradient. The sensitized cells were quite stable in liquid as well as in lyophilized state both at -70 degrees C and 4-8 degrees C. These cells could be used for two years without much loss (4-8 times loss) in titre. The IHA test was as sensitive as the neutralization (N) test performed by plaque reduction method in chick embryo fibroblasts. The sensitivity of the test was influenced by the source of erythrocytes i.e., from the different sheep from which these were drawn. After standardization of the test, 16 human sera and 18 sera of immunized mice were assayed for antibodies against JE virus by N and IHA tests. There were no significant differences between titres of both human and mice sera determined by N and IHA tests (P greater than 0.05). The correlation coefficient between N and IHA titres for human sera was 0.60 (P less than 0.05) and for mice sera 0.82 (P less than 0.01). The IHA test has been found to be very simple, inexpensive, sensitive and reproducible.


Subject(s)
Antibodies, Viral/blood , Antigens, Viral/immunology , Encephalitis Virus, Japanese/immunology , Hemagglutination Tests , Animals , Humans , Mice , Neutralization Tests , Predictive Value of Tests , Rabbits
20.
Indian J Med Res ; 89: 362-7, 1989 Nov.
Article in English | MEDLINE | ID: mdl-2559892

ABSTRACT

The immune status of 40 volunteers who received the full course of Japanese encephalitis (JE) vaccine a year earlier and 15 individuals who had received only a booster dose at the same time, was studied by estimating the level of persistence of protective antibody in the sera. All the sera showed persistence of 100 per cent seroconversion rate. Individuals who had the full course of vaccination still had high levels of antibody (mean 2.8 Iog10); however there was a fall of 0.8 Iog10 from the post-booster level. Volunteers who had received only a booster dose, also showed persistence of high level of protective antibody (mean 2.4 Iog10), a drop of 0.9 Iog10 from the post-booster level. Neutralizing (N) antibody estimated using Dibrugarh (7812474) strain of JE virus also demonstrated persistence of high level of protective antibody against this virus (mean 2.4 Iog10). Persistence of high level of protective antibody against homologus and heterologus (Dibrugarh) virus strains and absence of vaccine related side-effects even one year after administration of JE vaccine produced in India, demonstrates the immunizing potency and safety of this new vaccine.


Subject(s)
Antibodies, Viral/analysis , Encephalitis Virus, Japanese/immunology , Encephalitis, Japanese/immunology , Viral Vaccines/immunology , Adolescent , Adult , Humans , Immunity, Active , Immunization, Secondary , Male , Middle Aged , Neutralization Tests
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