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1.
Environ Res ; 248: 118317, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38301761

RESUMEN

The Third Pole (TP) is a high mountain region in the world, and is well-known for its pristine environment, but recent development activities in the region have degraded its air quality. Here, we investigate the spatial and temporal changes of the air pollutants ammonia (NH3), sulphur dioxide (SO2) and carbon monoxide (CO) in TP, and reveal their sources using satellite measurements and emission inventory. We observe a clear seasonal cycle of NH3 in TP, with high values in summer and low values in winter. The intense agriculture activities in the southern TP are the cause of high NH3 (6-8 × 1016 molec./cm2) there. Similarly, CO shows a distinct seasonal cycle with high values in spring in the southeast TP due to biomass burning. In addition, the eastern boundary of TP in the Sichuan and Qinghai provinces also show high values of CO (about 1.5 × 1018 mol/cm2), primarily owing to the industrial activities. There is no seasonal cycle found for SO2 distribution in TP, but relatively high values (8-10 mg/m2) are observed in its eastern boundary. The high-altitude pristine regions of inner TP are also getting polluted because of increased human activities in and around TP, as we estimate positive trends in CO (0.5-1.5 × 1016 mol/cm2/yr) there. In addition, positive trends are also found in NH3 (0.025 × 1016 molec./cm2/yr) during 2008-2020 in most regions of TP and SO2 (about 0.25-0.75 mg/m2/yr) in the Sichuan and Qinghai region during 2000-2020. As revealed by the emission inventory, there are high anthropogenic emissions of NH3, SO2 and CO within TP. There are emissions of pollutants from energy sectors, oil and refinery, agriculture waste burning and manure management within TP. These anthropogenic activities accelerate the ongoing development in TP, but severely erode its environment.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Humanos , Monitoreo del Ambiente , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Estaciones del Año , Dióxido de Azufre
2.
Environ Res ; 238(Pt 1): 117105, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37689338

RESUMEN

We analyse the long-term (1980-2020) changes in aerosols over the Third Pole (TP) and assess the changes in radiative forcing (RF) using satellite, ground-based and reanalysis data. The annual mean aerosol optical depth (AOD) varies from 0.06 to 0.24, with the highest values of around 0.2 in the north and southwest TP, which are dominated by dust from Taklimakan and Thar deserts, respectively. However, Organic Carbon (OC), Black Carbon (BC) and sulphate aerosols have significant contributions to the total AOD in the south and east TP. High amounts of dust are observed in spring and summer, but BC in winter. Trajectory analysis reveals that the air mass originated from East and South Asia carries BC and OC, whereas the air from South Asia, Central Asia and Middle East brings dust to TP. Significant positive trends in AOD is found in TP, with high values of about 0.002/yr in the eastern and southern TP. There is a gradual increase in BC and OC concentrations during 1980-2020, but the change from 2000 is phenomenal. The RF at the top of the atmosphere varies from -10 to 2 W/m2 in TP, and high positive RF of about 2 W/m2 is estimated in Pamir, Karakoram and Nyainquentanglha mountains, where the massive glacier mass exists. The RF has increased in much of TP during recent decades (2001-2020) with respect to previous decades (1981-2000), which can be due to the rise in BC and dust during the latter period. Therefore, the positive trend in BC and its associated change in RF can amplify the regional warming, and thus, the melting of glaciers or ice in TP. This is a great concern as it is directly connected to the water security of many South Asian countries.


Asunto(s)
Contaminantes Atmosféricos , Contaminantes Atmosféricos/análisis , Cambio Climático , Polvo/análisis , Estaciones del Año , Aerosoles/análisis , Carbono/análisis , Monitoreo del Ambiente/métodos
3.
Appl Geogr ; 151: 102869, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36619606

RESUMEN

The direct effect of pandemic induced lockdown (LD) on environment is widely explored, but its secondary impacts remain largely unexplored. Therefore, we assess the response of surface greenness and photosynthetic activity to the LD-induced improvement of air quality in India. Our analysis reveals a significant improvement in air quality marked by reduced levels of aerosols (AOD, -19.27%) and Particulate Matter (PM 2.5, -23%) during LD (2020)from pre-LD (March-September months for the period 2017-2019). The vegetation exhibits a positive response, reflected by the increase in surface greenness [Enhanced Vegetation Index (EVI, +10.4%)] and photosynthetic activity [Solar Induced Fluorescence (SiF, +11%)], during LD from pre-LD that coincides with two major agricultural seasons of India; Zaid (March-May) and Kharif (June-September). In addition, the croplands show a higher response [two-fold in EVI (14.45%) and four-fold in SiF (17.7%)] than that of forests. The prolonged growing period (phenology) and high rate of photosynthesis (intensification) led to the enhanced greening during LD owing to the reduced atmospheric pollution. This study, therefore, provides new insights into the response of vegetation to the improved air quality, which would give ideas to counter the challenges of food security in the context of climate pollution, and combat global warming by more greening.

4.
Sci Total Environ ; 946: 174111, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38908582

RESUMEN

There are substantial changes in the global drylands owing to climate change and anthropogenic activities. However, this aspect is not adequately explored in the context of recent climate change and global warming. Therefore, we analyse the role of water vapour in driving precipitation and corresponding surface greenness in the global deserts using satellite measurements. Statistical techniques such as partial correlation and Randon Forest (RF) are employed to understand the relationship among the physical processes that drive water availability for desert greening. Our analysis shows that water vapour is relatively lower (<25 kg/m2) in the deserts than rest of the globe, but comparable to the polar and high-altitude regions. Among the deserts, Thar (25 kg/m2) and Sahara (15-20 kg/m2) show higher water vapour, in contrast to the American and Gobi deserts (<10 kg/m2). Trajectory analysis reveals that water vapour transport from the south Atlantic Ocean is very high (90 kg/m/s) to the Sahel region of Sahara. Similarly, water vapour comes from Arabian Sea and Indian Ocean to Thar, mainly during Indian Summer Monsoon (ISM). There is an increase in water vapour driven by a rise in moisture transport to the American, Arabian, Thar and Sub-Sahara deserts during the period 2003-2020. The rise in moisture transport and associated water vapour in the deserts enhance water availability through precipitation and soil moisture, influencing surface greenness, as illustrated by the partial correlation and RF analyses. Enhanced water vapour and water availability, together with anthropogenic activities such as agriculture and afforestation in the deserts drive greening, which is more pronounced in Thar and Sub-Sahara. This study, thus, reveals the role of atmospheric moisture in regulating the terrestrial water availability and surface greenness in the extreme arid regions on the earth.

5.
Chemosphere ; 336: 139259, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37343635

RESUMEN

Carbon Monoxide (CO) is not a greenhouse gas (GHG), but has the capacity to change atmospheric chemistry of other GHGs such as methane and ozone, and therefore indirectly affects Earth's radiative forcing of the GHGs and surface temperature. Here, we use the CO mixing ratio at 850 hPa from the Tropospheric Emission Spectrometer (TES) reanalysis and the Measurement of Pollution in the Troposphere (MOPITT) satellite measurements for the period 2005-2019 to examine the spatio-temporal changes in CO across the latitudes. We find a substantial decrease in global CO, about -0.21 ± 0.09 ppb/yr (-0.23 ± 0.12%/yr) with the TES data and about -0.36 ± 0.07 ppb/yr (-0.45 ± 0.08%/yr) with the MOPITT satellite measurements during the study period. The highest CO decreasing trend is observed in Eastern China (-2.7 ± 0.37 ppb/yr) followed by Myanmar (-2.142 ± 0.59 ppb/yr) and South America (-1.08 ± 0.82 ppb/yr). This negative trend in CO is primarily due to the decrease in biomass burning and stringent environmental regulations in the respective regions and countries. The sources including road transport, which account for about 33.6% of CO emissions, followed by industries (18.3%) and agricultural waste burning (8.8%), might also be responsible for the reduction in CO due to the adaptation of improved emission control technology and regulations in the past decades from 2005 to 2019. Therefore, the study provides new insights on the current trends of global CO distribution and reasons for recent reduction in global CO emissions, which would be useful for future decision-making process to control air pollution.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Ozono , Monóxido de Carbono/análisis , Contaminantes Atmosféricos/análisis , Contaminación del Aire/prevención & control , Contaminación del Aire/análisis , Ozono/análisis , Tecnología
6.
Environ Pollut ; 335: 122269, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37524239

RESUMEN

The COVID-19 lockdown (LD) provided a unique opportunity to examine the changes in regional and global air quality. Changes in the atmospheric carbon monoxide (CO) during LD warrant a thorough analysis as CO is a major air pollutant that affects human health, ecosystem and climate. Our analysis reveals a decrease of 5-10% in the CO column during LD (April-May 2020) compared to the pre-lockdown (PreLD, March 2020) periods in regions with high anthropogenic activity, such as East China (EC), Indo-Gangetic Plain (IGP), North America, parts of Europe and Russia. However, this reduction did not occur in the regions of frequent and intense wildfires and agricultural waste burning (AWB). We find high heterogeneity in the CO column distributions, from regional to city scales during the LD period. To determine the sources of CO emissions during LD, we examined the ratios of nitrogen dioxide (NO2), sulfur dioxide (SO2) to CO for major cities in the world. This facilitated the identification of contributions from different sources; including vehicles, industries and biomass burning during LD. The comparison between CO levels during the LD and PreLD periods indicates a notable reduction in the global tropospheric CO, but no significant change in the stratosphere. It is found that CO emissions decreased during LD in the hotspot regions, but rebounded after the LD restrictions were lifted. This study, therefore, highlights the importance of policy decisions and their implementations in the global and regional scales to improve the air quality, and thus to protect public health and environment.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , COVID-19 , Humanos , Ecosistema , Material Particulado/análisis , Monitoreo del Ambiente , Control de Enfermedades Transmisibles , Contaminación del Aire/análisis , Contaminantes Atmosféricos/análisis
7.
Sci Total Environ ; 838(Pt 1): 155885, 2022 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-35595133

RESUMEN

The increase in greenhouse gases (GHGs) due to anthropogenic activities enhances regional and global temperatures. The most abundant GHG, i.e., water vapour, has a vital positive feedback on the global warming and Earth's climate system. This study focuses on the spatial and temporal changes in water vapour in the troposphere over India and Indian Ocean as derived from the ground-based, satellite and reanalyses data, and assesses the impact on water vapour changes on the regional climate by analysing radiative effects. The analyses show that the annual mean column water vapour (CWV) is high over the northern Indian Ocean, Bay of Bengal and Peninsular India, ranging from 30 to 60 kg/m2. Most regions show significant positive trends in the annual mean CWV, about 0.1-0.2 kg/m2/yr. There is a significant positive trend in water vapour in the troposphere (except 200 hPa) over the India land regions, with the highest values at 1000 hPa (0.034 g/kg/yr). The corresponding water vapour radiative effect (WVRE) is about 20-80 W/m2, depending on seasons and regions. This study, therefore, indicates that the increase in tropospheric water vapour over India and Indian Ocean could affect the regional temperature and climate.


Asunto(s)
Clima , Vapor , Calentamiento Global , Océano Índico , Estaciones del Año
8.
Phys Med Biol ; 53(18): 5107-21, 2008 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-18723932

RESUMEN

The performance of high-sensitivity x-ray imagers may be limited by additive instrumentation noise rather than by quantum noise when operated at the low exposure rates used in fluoroscopic procedures. The equipment-invasive instrumentation noise measures (in terms of electrons) are generally difficult to make and are potentially not as helpful in clinical practice as would be a direct radiological representation of such noise that may be determined in the field. In this work, we define a clinically relevant representation for instrumentation noise in terms of noise-equivalent detector entrance exposure, termed the instrumentation noise-equivalent exposure (INEE), which can be determined through experimental measurements of noise-variance or signal-to-noise ratio (SNR). The INEE was measured for various detectors, thus demonstrating its usefulness in terms of providing information about the effective operating range of the various detectors. A simulation study is presented to demonstrate the robustness of this metric against post-processing, and its dependence on inherent detector blur. These studies suggest that the INEE may be a practical gauge to determine and compare the range of quantum-limited performance for clinical x-ray detectors of different design, with the implication that detector performance at exposures below the INEE will be instrumentation-noise limited rather than quantum-noise limited.


Asunto(s)
Algoritmos , Artefactos , Análisis de Falla de Equipo/métodos , Radiografía/instrumentación , Análisis de Falla de Equipo/normas , Radiografía/métodos , Radiografía/normas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estados Unidos
9.
Indian J Psychol Med ; 40(6): 528-533, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30533948

RESUMEN

CONTEXT: Elder abuse has devastating consequences such as poor quality of life, psychological distress and loss of property and security. Abuse of elderly patients with depression has not been adequately researched in India. AIMS: To explore the prevalence and predictors of abuse and its relation to various sociodemographic variables in elderly patients with depression. SETTINGS AND DESIGN: A cross-sectional, observational study carried out at a tertiary care centre in Jamnagar. METHODS AND MATERIALS: In all, 100 elderly patients with depression, attending Out Patient Department of Psychiatry at Shree M. P. Shah Government Medical College and Guru Gobind Singh Hospital, Jamnagar, were selected using simple random sampling by lottery method. Actual Abuse Tool and Elder Abuse Suspicion Index were used to detect abuse. Geriatric Depression Scale was used to assess depression, and Mini Mental State Examination was used to rule out dementia. STATISTICAL ANALYSIS: Descriptive statistics, Chi-square test, and binary logistic regression were used. RESULTS: The prevalence of abuse was 24%. Among those who had experienced abuse, 50% had experienced psychological abuse, 17% had experienced neglect, 8% had experienced exploitation and 4% had experienced physical abuse. About 54% of patients with severe depression had experienced abuse. Daughters-in-law (54%) and sons (42%) were the most common perpetrators. Illiteracy and severe depression were found to be the predictors of abuse.

10.
Leukemia ; 32(4): 920-930, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29099493

RESUMEN

Acalabrutinib, a highly selective Bruton's tyrosine kinase inhibitor, is associated with high overall response rates and durable remission in previously treated chronic lymphocytic leukemia (CLL); however, complete remissions were limited. To elucidate on-target and pharmacodynamic effects of acalabrutinib, we evaluated several laboratory endpoints, including proteomic changes, chemokine modulation and impact on cell migration. Pharmacological profiling of samples from acalabrutinib-treated CLL patients was used to identify strategies for achieving deeper responses, and to identify additive/synergistic combination regimens. Peripheral blood samples from 21 patients with relapsed/refractory CLL in acalabrutinib phase I (100-400 mg/day) and II (100 mg BID) clinical trials were collected prior to and on days 8 and 28 after treatment initiation and evaluated for plasma chemokines, reverse phase protein array, immunoblotting and pseudoemperipolesis. The on-target pharmacodynamic profile of acalabrutinib in CLL lymphocytes was comparable to ibrutinib in measures of acalabrutinib-mediated changes in CCL3/CCL4 chemokine production, migration assays and changes in B-cell receptor signaling pathway proteins and other downstream survival proteins. Among several CLL-targeted agents, venetoclax, when combined with acalabrutinib, showed optimal complementary activity in vitro, ex vivo and in vivo in TCL-1 adoptive transfer mouse model system of CLL. These findings support selective targeting and combinatorial potential of acalabrutinib.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/metabolismo , Adenina/análogos & derivados , Traslado Adoptivo/métodos , Animales , Linfocitos B/efectos de los fármacos , Linfocitos B/metabolismo , Benzamidas/administración & dosificación , Compuestos Bicíclicos Heterocíclicos con Puentes/administración & dosificación , Movimiento Celular/efectos de los fármacos , Quimiocina CCL3/metabolismo , Quimiocina CCL4/metabolismo , Ensayos Clínicos Fase I como Asunto , Ensayos Clínicos Fase II como Asunto , Terapia Combinada/métodos , Resistencia a Antineoplásicos/efectos de los fármacos , Humanos , Ratones , Piperidinas , Inhibidores de Proteínas Quinasas/administración & dosificación , Proteínas Tirosina Quinasas/metabolismo , Proteómica , Pirazinas/administración & dosificación , Pirazoles/administración & dosificación , Pirimidinas/administración & dosificación , Transducción de Señal/efectos de los fármacos , Sulfonamidas/administración & dosificación
11.
Mech Ageing Dev ; 10(1-2): 53-70, 1979 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-449423

RESUMEN

In 4 patients with neuronal ceroid-lipofuscinoses (NCL) (3 patients with the junvenile type, 1 patient with the late infantile type), the ultrastructural spectrum of residual bodies in the central and peripheral nervous system presented curvilinear profiles in all cases and regions investigated and many more ultrastructural patterns within and beyond regions commonly accessible to biopsy, probably due to age dependence, local tissue and cellular biochemical factors. Sampling from basal ganglia especially yielded combined curvilinear-fingerpint bodies, from peripheral ganglia additional membranous bodies. Residual bodies in NCL were present in almost every cell type, similar to the distribution of regular lipofuscin. Although the classical subgroups of NCL contain electronmicroscopically well defined residual bodies, permitting distinction of the late infantile type from the juvenile type, the ultrastructural differences are more of a quantitative than of a qualitative nature. However, they are not pathognomonic. N.m.r. spectra of ceroid and lipofuscin support the concept of their biochemical similarity, and argue against the proposition that they contain a single major component.


Asunto(s)
Encéfalo/ultraestructura , Ceroide , Ganglios/ultraestructura , Lipidosis/patología , Lipofuscina , Neuronas/ultraestructura , Pigmentos Biológicos , Niño , Femenino , Humanos , Lactante , Lipidosis/clasificación , Masculino , Organoides/ultraestructura , Células de Schwann/ultraestructura
12.
Autoimmunity ; 11(1): 35-43, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1812994

RESUMEN

Several prominent mycobacterial protein antigens involved in antibody and T cell responses have been identified as members of highly conserved heat shock protein families. In particular, immune responses to the mycobacterial 65 kD heat shock protein (hsp65) have been implicated in the pathogenesis of autoimmune diseases both in experimental animal models and in man. Additionally, hsp65 has been shown to modulate the course of autoimmune disease in such experimental animal systems. In this report, we have examined the synthesis of heat shock proteins by a fast growing mycobacterial strain, M. vaccae, in heat stressed cultures and used the pristane induced arthritis model to investigate the immunoprophylactic and immunotherapeutic potential of heat killed M. vaccae. Heat shock of M. vaccae cultures at 48 degrees C demonstrated a 43-fold increase in hsp65 over that expressed at 37 degrees C. It is therefore suggested that heat killed M. vaccae contains sufficient hsp that can be presented in the context of appropriate adjuvant properties for use as an effective immunomodulatory agent. Immunisation experiments with M. vaccae revealed that protection or exacerbation of pristane induced arthritis was dependent on the dose (given in an oil or aqueous suspension), route and time of immunisation. In addition, it was demonstrated that the development of arthritis correlated with high levels of agalactosyl IgG and that "protected" animals had significantly depressed levels.


Asunto(s)
Antígenos Bacterianos/uso terapéutico , Artritis/prevención & control , Artritis/terapia , Inmunoterapia , Mycobacterium/inmunología , Animales , Artritis/inducido químicamente , Autorradiografía , Carcinógenos , Densitometría , Modelos Animales de Enfermedad , Relación Dosis-Respuesta Inmunológica , Electroforesis en Gel de Poliacrilamida , Adyuvante de Freund/farmacología , Proteínas de Choque Térmico/inmunología , Proteínas de Choque Térmico/uso terapéutico , Inmunoglobulina G/biosíntesis , Inyecciones Intraperitoneales , Inyecciones Subcutáneas , Masculino , Ratones , Ratones Endogámicos CBA , Mycobacterium/metabolismo , Terpenos , Vacunación
13.
Psychopharmacology (Berl) ; 71(1): 101-3, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-6779318

RESUMEN

Newly synthesized glutarimide compounds (Table 1) at doses of 4, 8 and 16 mg/kg (IP) reduced the duration of sleep induced by pentobarbitone in mice. Compounds 1 to 7 and 21 were more potent than the other compounds and their activity was comparable to the reference drug, bemegride. The structure activity relationship for the decrease in duration of barbiturate anaesthesia caused by the various groups of these compounds was mainly found to be inversely related to the length of the alkyl side chain at position 4 of the beta carbon atom. It was also shown that the presence of piperidine, diethylamine and morpholine moieties attached to 3,5-dicyanoglutarimide was partly responsible for the reduction in barbiturate anaesthesia by these compounds.


Asunto(s)
Pentobarbital/antagonistas & inhibidores , Piperidinas/farmacología , Piperidonas/farmacología , Sueño/efectos de los fármacos , Animales , Ratones , Relación Estructura-Actividad , Factores de Tiempo
14.
Metabolism ; 40(9): 883-7, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1895952

RESUMEN

The genetics of malignant hyperthermia (MH) are ill-understood; however, the association of Duchenne muscular dystrophy (DMD) with MH is well known. A deficiency of dystrophin is common to both the DMD and mdx mouse, an animal model for DMD. Using muscle contracture tests for MH, we have shown that in the mdx mouse there is no MH susceptibility, suggesting the lack of a direct role of the dystrophin in the development of MH syndrome.


Asunto(s)
Cafeína/farmacología , Contractura/inducido químicamente , Distrofina/deficiencia , Halotano/farmacología , Abdomen , Animales , Combinación de Medicamentos , Distrofina/genética , Ratones , Ratones Mutantes , Concentración Osmolar
15.
Brain Res Bull ; 27(6): 849-52, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1686215

RESUMEN

Recent experimental data indicate that endogenous brain ligands for the opioid receptors such as enkephalins, beta-endorphin (beta-End) and dynorphin (Dyn) may be involved in both generalized and partial seizures. The "tottering" (tg/tg) mouse provides an electrophysiological representation of generalized spontaneous human epilepsy. These mice exhibit behavioral absence seizures with accompanying spike-wave discharges. Methionine-enkephalin (M-Enk), beta-End and Dyn levels in various regions of brain were measured by radioimmunoassay (RIA) in 15-18-week-old tg/tg and control (+/+) mice to elucidate the relation between seizures and the opioid system. beta-End and Dyn levels were similar in tg/tg and +/+ mice. However, M-Enk levels were significantly increased in the striatum, cortex, pons and medulla of the tg/tg mice. Our data suggest that in the tottering mouse model of generalized epilepsy there is an alteration of enkephalinergic pathways and not of the endorphinergic or dynorphinergic pathways.


Asunto(s)
Encefalina Metionina/metabolismo , Epilepsia/metabolismo , Animales , Encéfalo/metabolismo , Dinorfinas/metabolismo , Epilepsia/genética , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes Neurológicos , Concentración Osmolar , Radioinmunoensayo , Distribución Tisular , betaendorfina/metabolismo
16.
Indian J Physiol Pharmacol ; 20(3): 172-6, 1976.
Artículo en Inglés | MEDLINE | ID: mdl-977087

RESUMEN

The effects of a new series of glutarimide compounds have been studied in acetylcholine induced auricular fibrillation in anaesthetized cats and epinephrine induced ventricular arrhythmmias in conscious pigeons. Some of the compounds showed varying degree of protective action against experimental arrhythmias. However these compounds were found to be less potent than quinidine. The mechanism of antiarrhythmic action has been discussed.


Asunto(s)
Antiarrítmicos/uso terapéutico , Piperidinas/uso terapéutico , Piperidonas/uso terapéutico , Acetilcolina , Anestesia Local , Animales , Fibrilación Atrial/inducido químicamente , Fibrilación Atrial/tratamiento farmacológico , Gatos , Columbidae , Epinefrina , Femenino , Cobayas , Imidas/uso terapéutico , Masculino , Conejos , Fibrilación Ventricular/inducido químicamente , Fibrilación Ventricular/tratamiento farmacológico
17.
J Perinatol ; 34(5): 364-8, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24556982

RESUMEN

OBJECTIVE: To investigate the impact of early skin-to-skin contact (SSC) provided for first 24 h on incidence of hypothermia in stable newborns weighing 1800 g or more during first 48 h of life. STUDY DESIGN: Stable newborns (term and late preterm: Mean gestational age 37.7 (1.35) weeks, range 34-40 weeks) having birth weight 1800 g or more (Mean weight 2605.6 (419.8) grams) were enrolled after approval from Institutional Human Research Ethics Committee (CTRI/2013/06/003790) and randomized into early SSC (intervention group) and conventional care (control group). Initial care in the delivery room for few minutes immediately after birth in both the groups was given under radiant warmer. In the intervention group, newborns were provided SSC by their mother started between 30 min and 1 h after birth for first 24 h with minimal interruption and were provided conventional care other than SSC for next 24 h of life. In the control group, newborns were kept with their mother and received conventional care other than SSC for first 48 h. Temperature and heart rate of newborns were recorded at 30 min, 1, 2, 3, 4, 5, 6, 12, 24 and at 48 h of life in both the groups. Independent Samples t-Test and relative risk were used to analyze the data. RESULT: Both groups had 50 neonates each with similar baseline characteristics. Heart rates were in normal range in both the groups. The intervention group provided an average (s.d.) of 16.98 (0.28) h of SSC over the first 24 h period. The mean temperature was significantly high in the SSC group at all time intervals starting from 1 to 48 h (P<0.05 for all). In the SSC group only two newborns (4%) had mild hypothermia (cold stress), and, of these two newborns, one had two episodes of hypothermia. All these three episodes of hypothermia occurred within first 3 h of life. In the control group 16 newborns (32%) developed hypothermia (temperature<36.5 °C) during first 48 h of life. Of them, 11 newborns had single episode, 4 newborns had two episodes and one newborn had three episodes of hypothermia. Of these 22 hypothermic episodes, 20 occurred in the first 6 h of life and 2 episodes occurred at 48 h of life. Moderate hypothermia was seen in two newborns, whereas rest had mild hypothermia. The relative risk of developing hypothermia in the control group as compared with the SSC group was 8.00 (95% CI 1.94-32.99). There was no seasonal variation in incidence of hypothermia in both the groups. CONCLUSION: Newborns in the SSC group achieved rapid thermal control as compared with the control group. Early SSC for 24 h after birth decreases incidence of hypothermia for initial 48 h of life. Early SSC needs to be aggressively promoted in term and late-preterm newborns to reduce incidence of hypothermia.


Asunto(s)
Regulación de la Temperatura Corporal/fisiología , Hipotermia/epidemiología , Recién Nacido/fisiología , Relaciones Madre-Hijo , Piel , Femenino , Humanos , Recien Nacido Prematuro , Embarazo
18.
Indian J Microbiol ; 50(Suppl 1): 132-8, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22815586

RESUMEN

Secretion and enzymatic characteristics of lignin peroxidases from Gloeophyllum sepiarium MTCC 1170, Cladosporium herbarum MTCC 346, Lenzites betulina MTCC 1183, Daedalea flavida MTCC 145, Hexagonia teruis MTCC 1119 and Coirolopsis floccosa MTCC 1177 ligninolytic fungal strains have been reported. Secretion of lignin peroxidase by these ligninolytic fungal strains have been found to be in the range of 0.86 to 3.0 enzyme unit per ml of the culture medium. The enzymatic characteristics like K(m), pH and temperature optima of all the lignin peroxidases of the above fungal strains have been determined using veratryl alcohol and H(2)O(2) as the variable substrates. The K(m) values using veratryl alcohol as the substrate were found to be 65.0 µM, 58.5 µM, 63.0 µM, 54.5 µM, 54.6 µM and 61.0 µM respectively. The K(m) values using H(2)O(2) as the substrate were found to be 88.0 µM, 86.0 µM, 71.0 µM, 67.0 µM, 80.0 µM and 78.0 µM respectively. The pH optima values for lignin peroxidases of the above ligninolytic fungal strains were found to be 2.5, 2.4, 2.4, 2.25, 2.5 and 2.8 respectively, where as the temperature optima values were 25°C, 24°C, 25°C, 23°C, 24°C and 25°C respectively.

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