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Sharma BR, Kuttippurath J, Patel VK, Gopikrishnan GS. Regional sources of NH 3, SO 2 and CO in the Third Pole. Environ Res 2024; 248:118317. [PMID: 38301761 DOI: 10.1016/j.envres.2024.118317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 01/15/2024] [Accepted: 01/24/2024] [Indexed: 02/03/2024]
Abstract
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.
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Affiliation(s)
- B R Sharma
- CORAL, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
| | - J Kuttippurath
- CORAL, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India.
| | - V K Patel
- CORAL, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
| | - G S Gopikrishnan
- CORAL, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
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Sharma BR, Kuttippurath J, Patel VK. A gradual increase of aerosol pollution in the Third Pole during the past four decades: Implication for regional climate change. Environ Res 2023; 238:117105. [PMID: 37689338 DOI: 10.1016/j.envres.2023.117105] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Revised: 09/03/2023] [Accepted: 09/06/2023] [Indexed: 09/11/2023]
Abstract
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.
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Affiliation(s)
- B R Sharma
- CORAL, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India; Department of Physics, Prithvinarayan Campus, Tribhuvan University, Pokhara, Nepal
| | - J Kuttippurath
- CORAL, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India.
| | - V K Patel
- CORAL, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
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Pathak M, Patel VK, Kuttippurath J. Spatial heterogeneity in global atmospheric CO during the COVID-19 lockdown: Implications for global and regional air quality policies. Environ Pollut 2023; 335:122269. [PMID: 37524239 DOI: 10.1016/j.envpol.2023.122269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 07/20/2023] [Accepted: 07/25/2023] [Indexed: 08/02/2023]
Abstract
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.
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Affiliation(s)
- M Pathak
- CORAL, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
| | - V K Patel
- CORAL, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
| | - J Kuttippurath
- CORAL, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India.
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McBenedict B, Hauwanga WN, Elamin A, Eshete FD, El Husseini N, El Ghazzawi AA, Patel VK, Pessôa BL, Tolentino J, Mesquita ET. Cerebrovascular Disease Mortality Trends in Brazil: An In-Depth Joinpoint Analysis. Cureus 2023; 15:e45845. [PMID: 37881379 PMCID: PMC10594394 DOI: 10.7759/cureus.45845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/24/2023] [Indexed: 10/27/2023] Open
Abstract
Background Cerebrovascular disease is the second leading cause of death and the third leading cause of disability following heart disease. In 2019, there were over 101 million people living with a stroke and 12.2 million incidents of stroke globally. For the past three decades, stroke has remained the leading cause of death in Brazil, causing over 100,000 fatalities annually, along with numerous functional impairments among those who survive. The Brazilian healthcare system has witnessed notable advancements in the last decade, including the establishment of additional hospitals and a rise in the count of healthcare professionals specializing in cardiovascular and neurological surgery. However, there exists a gap in the research landscape for continuous comprehensive studies aimed at exploring the evolving mortality rates related to cerebrovascular diseases, of which the last one included data up to 2019. This study aimed to address this gap by meticulously analyzing the trends in cerebrovascular disease mortality in Brazil from 2000 to 2021, for the variables age, sex, state of residence, and geographic region. Methods This is a descriptive, ecological, and time series study. Nationwide data for annual cerebrovascular mortality from Brazil were used for the period 2000-2021. Age-adjusted mortality rates (AAMRs) by direct standardization, encompassing people above 20 years of age, were calculated and expressed per 100,000 persons. Mortality trends were assessed using joinpoint regression analysis by calculating the annual percentage change (APC) and its corresponding 95% confidence interval (CI) across categories of age, sex, and state and region of residence. Results The mortality rates decreased for the sex categories over the analyzed years. The AAMR for the categories decreased as follows: males and females (95 deaths/100,000 to 52 deaths/100,000 inhabitants), males (108 deaths/100,000 to 63 deaths/100,000 inhabitants), and females (83 deaths/100,000 to 44 deaths/100,000 inhabitants). The most substantial reduction in AAMR for males occurred in the 30-39-year age group (APC: -4.10), while the smallest decline was observed in the 20-29-year age group (APC: -1.44). All five macro-regions demonstrated statistically significant and downward AAPC values in mortality rates. The south and midwest regions decreased at a stable rate, as denoted by the same APC and AAPC values (-4.05 and -3.11, respectively). The north and northeast regions exhibited an increase in AAMR, followed by a decrease (APC: 0.68 to -1.42 and 2.63 to -2.35, respectively). Conclusions Our comprehensive analysis revealed a downward trend in cerebrovascular disease mortality rates across diverse demographic groups and macro-regions. Females experienced a more substantial reduction compared to males. Despite higher mortality rates among individuals aged 50 and above, all age groups displayed a marked decrease. The continuous decline can be attributed to policy interventions aimed at enhancing healthcare delivery, increased awareness, and healthier diets and lifestyles. With regard to the macro-regions, the regions in the southern zone demonstrated a more significant decrease as compared to the northern part. In Brazil, a more significant decline in cerebrovascular disease mortality rates could be achieved through increased focus on prevention measures and efforts toward mitigating disparities and inequalities between macro-regions.
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Affiliation(s)
- Billy McBenedict
- General and Specialized Surgery, Universidade Federal Fluminense, Niteroi, BRA
| | - Wilhelmina N Hauwanga
- General and Specialized Surgery, Universidade Federal do Estado do Rio de Janeiro, Rio de Janeiro, BRA
| | | | | | | | | | | | - Bruno L Pessôa
- General and Specialized Surgery, Universidade Federal Fluminense, Niteroi, BRA
| | - Julio Tolentino
- General and Specialized Surgery, Universidade Federal do Estado do Rio de Janeiro, Rio de Janeiro, BRA
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Joshi A, Pathak M, Kuttippurath J, Patel VK. Adoption of cleaner technologies and reduction in fire events in the hotspots lead to global decline in carbon monoxide. Chemosphere 2023:139259. [PMID: 37343635 DOI: 10.1016/j.chemosphere.2023.139259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 05/12/2023] [Accepted: 06/16/2023] [Indexed: 06/23/2023]
Abstract
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 that 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 adaptation of improved emission control technology and regulations in the past decade 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.
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Affiliation(s)
- A Joshi
- Coral, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
| | - M Pathak
- Coral, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
| | - J Kuttippurath
- Coral, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India.
| | - V K Patel
- Coral, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
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Kashyap R, Kuttippurath J, Patel VK. Improved air quality leads to enhanced vegetation growth during the COVID-19 lockdown in India. Appl Geogr 2023; 151:102869. [PMID: 36619606 PMCID: PMC9805897 DOI: 10.1016/j.apgeog.2022.102869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 12/28/2022] [Accepted: 12/29/2022] [Indexed: 06/17/2023]
Abstract
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.
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Affiliation(s)
- Rahul Kashyap
- CORAL, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
| | - J Kuttippurath
- CORAL, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
| | - V K Patel
- CORAL, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
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Patel VK, Kuttippurath J. Significant increase in water vapour over India and Indian Ocean: Implications for tropospheric warming and regional climate forcing. Sci Total Environ 2022; 838:155885. [PMID: 35595133 DOI: 10.1016/j.scitotenv.2022.155885] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 05/08/2022] [Accepted: 05/08/2022] [Indexed: 06/15/2023]
Abstract
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.
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Affiliation(s)
- V K Patel
- CORAL, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - J Kuttippurath
- CORAL, Indian Institute of Technology Kharagpur, Kharagpur 721302, India.
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Nimbalkar SM, Patel VK, Patel DV, Nimbalkar AS, Sethi A, Phatak A. Effect of early skin-to-skin contact following normal delivery on incidence of hypothermia in neonates more than 1800 g: randomized control trial. J Perinatol 2014; 34:364-8. [PMID: 24556982 DOI: 10.1038/jp.2014.15] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 12/17/2013] [Accepted: 01/06/2014] [Indexed: 01/21/2023]
Abstract
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.
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Affiliation(s)
- S M Nimbalkar
- Department of Pediatrics, Pramukhswami Medical College, Karamsad, Anand, India
| | - V K Patel
- Department of Pediatrics, Pramukhswami Medical College, Karamsad, Anand, India
| | - D V Patel
- Department of Pediatrics, Pramukhswami Medical College, Karamsad, Anand, India
| | - A S Nimbalkar
- Department of Pediatrics, Pramukhswami Medical College, Karamsad, Anand, India
| | - A Sethi
- Department of Pediatrics, Pramukhswami Medical College, Karamsad, Anand, India
| | - A Phatak
- Department of Pediatrics, Pramukhswami Medical College, Karamsad, Anand, India
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Sharma A, Chandraker S, Patel VK, Ramteke P. Antibacterial Activity of Medicinal Plants Against Pathogens causing Complicated Urinary Tract Infections. Indian J Pharm Sci 2011; 71:136-9. [PMID: 20336211 PMCID: PMC2839399 DOI: 10.4103/0250-474x.54279] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2008] [Revised: 01/05/2009] [Accepted: 03/31/2009] [Indexed: 11/04/2022] Open
Abstract
Seventeen Indian folklore medicinal plants were investigated to evaluate antibacterial activity of aqueous, ethanol and acetone extracts against 66 multidrug resistant isolates of major urinary tract pathogens (Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Enterococcus faecalis) by disc diffusion method. Ethanol extract of Zingiber officinale and Punica granatum showed strong antibacterial activity against Escherichia coli. Ethanol extracts of Terminalia chebula and Ocimum sanctum exhibited antibacterial activity against Klebsiella pneumoniae. Ethanol extract of Cinnamomum cassia showed maximum antibacterial activity against Pseudomonas aeruginosa while ethanol extract of Azadirachta indica and Ocimum sanctum exhibited antibacterial activity against Enterococcus faecalis. The results support the folkloric use of these plants in the treatment of urinary tract infections by the tribals of Mahakoshal region of central India.
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Affiliation(s)
- Anjana Sharma
- Bacteriology Laboratory, Department of Post Graduate Studies and Research in Biological Sciences, R. D. University, Jabalpur-482 001, India
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Yadava GK, Kuhls-Gilcrist AT, Rudin S, Patel VK, Hoffmann KR, Bednarek DR. A practical exposure-equivalent metric for instrumentation noise in x-ray imaging systems. Phys Med Biol 2008; 53:5107-21. [PMID: 18723932 DOI: 10.1088/0031-9155/53/18/017] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
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.
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Affiliation(s)
- G K Yadava
- Toshiba Stroke Research Center, State University of New York at Buffalo, Buffalo, NY 14214, USA
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Menon SR, Patel VK, Mitscher LA, Shih P, Pillai SP, Shankel DM. Structure-antimutagenic activity relationship study of plicatin B. J Nat Prod 1999; 62:102-106. [PMID: 9917292 DOI: 10.1021/np980304n] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A systematic structure-activity relationship study of plicatin B (1), an antimutagenic constituent of Psoralea juncea, was undertaken with a view toward elucidating its chemical mode of action and possibly optimizing its antimutagenic activity during the process. Compound 1 and its related analogues were examined for their antimutagenic activity against mutations induced by ethyl methanesulfonate, a direct acting mutagen and alkylating agent, in Salmonella typhimurium strain TA100, utilizing the modified Ames test protocol. The dihydro analogue 3 resulting from saturation of the conjugated alkene double bond of 1 was found to exhibit reduced cytotoxicity and enhanced efficacy relative to the parent compound. This result serves preliminarily to exclude a Michael acceptor role of the alpha,beta-unsaturated carbonyl moiety in connection with its antimutagenic activity.
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Affiliation(s)
- S R Menon
- Department of Medicinal Chemistry and Department of Microbiology, University of Kansas, Lawrence, Kansas 66045, USA
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Israel EJ, Patel VK, Taylor SF, Marshak-Rothstein A, Simister NE. Requirement for a beta 2-microglobulin-associated Fc receptor for acquisition of maternal IgG by fetal and neonatal mice. The Journal of Immunology 1995. [DOI: 10.4049/jimmunol.154.12.6246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
There is considerable evidence to suggest that an FcR similar in structure to class I MHC Ags, neonatal Fc receptor (FcRn), transports IgG across the intestinal epithelium of suckling mice. However, this has not previously been shown definitively, nor has it been shown whether FcRn is the only, or even the major, IgG transporter in the neonatal mouse gut. We report here that neonatal mice homozygous for a targeted disruption of the beta 2microglobulin (beta 2m) gene, which encodes one subunit of FcRn, had reduced FcRn alpha-chain at the lumenal plasma membrane of intestinal cells. These mice had strikingly lower serum IgG levels during the first month after birth than littermates that possessed functional FcRn. Furthermore, we found by fostering mice on mothers with a different IgG allotype that all of the IgG in sera of beta 2m-/- mice was endogenous, and that none was obtained from milk. We conclude that FcRn is the only transporter of IgG from mother to young in the mouse. The onset of IgG synthesis in mice that received no milk IgG lagged behind that in siblings with normal IgG transport, suggesting that maternal IgG stimulates Ab production in the neonate. We noted no difference between the IgG concentrations in the milk of beta 2m-/- and beta 2m+/- mice, indicating that FcRn is not involved in the secretion of IgG into milk.
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Affiliation(s)
- E J Israel
- Combined Program in Pediatric Gastroenterology and Nutrition, Harvard Medical School, Massachusetts General Hospital, Boston 02114, USA
| | - V K Patel
- Combined Program in Pediatric Gastroenterology and Nutrition, Harvard Medical School, Massachusetts General Hospital, Boston 02114, USA
| | - S F Taylor
- Combined Program in Pediatric Gastroenterology and Nutrition, Harvard Medical School, Massachusetts General Hospital, Boston 02114, USA
| | - A Marshak-Rothstein
- Combined Program in Pediatric Gastroenterology and Nutrition, Harvard Medical School, Massachusetts General Hospital, Boston 02114, USA
| | - N E Simister
- Combined Program in Pediatric Gastroenterology and Nutrition, Harvard Medical School, Massachusetts General Hospital, Boston 02114, USA
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14
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Israel EJ, Patel VK, Taylor SF, Marshak-Rothstein A, Simister NE. Requirement for a beta 2-microglobulin-associated Fc receptor for acquisition of maternal IgG by fetal and neonatal mice. J Immunol 1995; 154:6246-51. [PMID: 7759862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
There is considerable evidence to suggest that an FcR similar in structure to class I MHC Ags, neonatal Fc receptor (FcRn), transports IgG across the intestinal epithelium of suckling mice. However, this has not previously been shown definitively, nor has it been shown whether FcRn is the only, or even the major, IgG transporter in the neonatal mouse gut. We report here that neonatal mice homozygous for a targeted disruption of the beta 2microglobulin (beta 2m) gene, which encodes one subunit of FcRn, had reduced FcRn alpha-chain at the lumenal plasma membrane of intestinal cells. These mice had strikingly lower serum IgG levels during the first month after birth than littermates that possessed functional FcRn. Furthermore, we found by fostering mice on mothers with a different IgG allotype that all of the IgG in sera of beta 2m-/- mice was endogenous, and that none was obtained from milk. We conclude that FcRn is the only transporter of IgG from mother to young in the mouse. The onset of IgG synthesis in mice that received no milk IgG lagged behind that in siblings with normal IgG transport, suggesting that maternal IgG stimulates Ab production in the neonate. We noted no difference between the IgG concentrations in the milk of beta 2m-/- and beta 2m+/- mice, indicating that FcRn is not involved in the secretion of IgG into milk.
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Affiliation(s)
- E J Israel
- Combined Program in Pediatric Gastroenterology and Nutrition, Harvard Medical School, Massachusetts General Hospital, Boston 02114, USA
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15
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Abstract
Because of the demonstration of a genetic linkage between glucokinase and Type II diabetes, and the central role of glucokinase on glucose metabolism, we studied glucokinase activity in the liver of patients with and without Type II diabetes. Glucokinase activity was decreased by about 50% in obese subjects with diabetes (n = 12) compared with (p < 0.01) lean controls (n = 9) and (p < 0.05) obese controls (n = 10). There was no difference between lean and obese controls. Fifty percent of subjects with diabetes had lower liver glucokinase activity than the lowest value of the controls. These data further support the important role that glucokinase plays in the pathogenesis of Type II diabetes.
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Affiliation(s)
- J F Caro
- Department of Medicine, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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16
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Abstract
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.
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Affiliation(s)
- V K Patel
- Department of Pathology, Indiana University School of Medicine, Indianapolis 46202-5120
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17
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Abstract
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.
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Affiliation(s)
- V K Patel
- Department of Pathology, Indiana University Medical Center, Indianapolis
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18
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Abstract
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.
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Affiliation(s)
- S J Thompson
- Department of Pathology, University of Bristol, UK
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19
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Patel VK, Venkatakrishna-Bhatt H. Folklore therapeutic indigenous plants in periodontal disorders in India (review, experimental and clinical approach). Int J Clin Pharmacol Ther Toxicol 1988; 26:176-84. [PMID: 3042642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Though a number of plants and their parts are used for dental ailments among population in rural and urban areas of developing countries, in India however, the most common house-hold, road-side plants are mango (Mangifera indica), neem (Azadirachta indica; Melia azadirachta), ocimum (Ocimum basilicum), tea-dust (Camellia sinensis) and uncommonly murayya, i.e., currey leaf (Murayya koenigi) [Chopra et al. 1958, Kirtikar and Basu 1935, Nadakarni 1954, Satyavati 1984]. The leaves of these plants are folded and brushed (massage with teadust) against the teeth. Therefore, the present study is restricted only to the fleshy leaf extracts [Jindal et al. 1975] (except tea) of these plants inspite of certain limitations in the methodology and arbitrations in the microbial identification and isolation in the light of recent advances in folk dentistry. The investigation was carried out in two parts: 1) Experimental study: The efficacy of various dentifrices (commonly available in the market) and the potentiating effect of the leaf extract (LE) of the aforesaid indigenous plants when amalgamated with the tooth-paste against pathogens, were investigated. Further, the protection afforded by the said plant extracts (PE) over the conventional allopathic medicines on the human plaque cultures and gram negative bacteria from patients were studied. 2) Clinical study: The therapeutic effects of the said PE (individually) on clinical application among severely infected patients were examined.
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Affiliation(s)
- V K Patel
- Department of Pharmacology and Therapeutics, Government Dental College and Hospitals, Asarva, Civil Hospital Compound, Ahmedabad, Gujarat, India
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20
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Abstract
1. The effect of exercise (2 hr treadmill running at 28 m/min) on PDHa (the activity of the active form of pyruvate dehydrogenase) in untrained rats, trained rats (2 hr/d at 25 m/min for 4 wk), and in 24 hr fasted rats was determined. 2. Exercise increased PDHa activity approximately 2 fold in fed-untrained rats. 3. Fasting decreased PDHa activity in sedentary rats to approximately half the activity in fed rats. 4. The increase in PDHa activity during exercise was less in fasted than fed rats. 5. Training did not change the total activity of PDH (phosphorylated plus nonphosphorylated forms) but the percent of PDH in the active form was increased in muscle of trained-rested rats. 6. PDHa activity was unchanged by acute exercise (2.5 hr at 40 m/min) in the trained rats.
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Affiliation(s)
- J T Brozinick
- Department of Biochemistry, School of Medicine, East Carolina University, Greenville, NC 27858
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21
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Abstract
Autopsy brain samples from patients with late-infantile, juvenile and adult forms of ceroid-lipofuscinosis (CL) and cultured skin fibroblasts from juvenile CL were analyzed for the content of phosphodolichol (P-Dol) related compounds. The levels of P-Dol obtained on treatment with hot dilute acid of the chloroform-methanol (CM 2:1) extract and the chloroform-methanol-water (CMW 1:1:3) extract of the residue were estimated by high performance liquid chromatography. Compared to age-matched control individuals, the levels of P-Dol obtained in both the extracts were increased more than 6.6 times in all the patient samples. Further analysis of the CMW extract indicates that the increased P-Dol is primarily due to oligosaccharyl diphosphodolichol. Cultured skin fibroblasts from the juvenile form of CL show normal level of free dolichol and elevated level of phosphorylated dolichols. Glycoprotein synthesis measured by incorporation of labeled glucosamine show no deficit in the transfer of oligosaccharides from lipids to proteins. A hypothesis is presented to explain the accumulation of oligosaccharyl diphosphodolichol and deficiency of lysosomal proteases in ceroid-lipofuscinosis.
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Affiliation(s)
- R K Pullarkat
- New York State Office of Mental Retardation and Developmental Disabilities Institute for Basic Research in Developmental Disabilities, Staten Island 10314
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22
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Abstract
Pyruvate dehydrogenase and phosphoenolpyruvate carboxykinase are important enzymes in the regulation of muscle pyruvate metabolism and their in vitro measured activities have been studied in muscle from rested and exercised rats. In addition, the muscle concentration of metabolic intermediates associated with pyruvate metabolism has been measured after exercise. Phosphoenolpyruvate concentration was decreased to less than half the value found in rested muscle but pyruvate concentration did not change. This suggests an increase in the in vivo rate of conversion of phosphoenolpyruvate to pyruvate. Concentrations of malate and aspartate increased two- to threefold which suggests that oxaloacetate concentration was also increased. An increase in oxaloacetate availability would increase acetyl CoA metabolism and therefore would increase pyruvate dehydrogenase activity in vivo. The basal activity of pyruvate dehydrogenase measured in vitro increased approximately twofold after 2 hr of exercise and returned to control values 5 min after the cessation of exercise. Total pyruvate dehydrogenase activity (activated to the maximal extent) was not changed by exercise. Muscle PEPCK activity was also increased during exercise suggesting an increased rate of conversion of oxaloacetate to pyruvate to provide net oxidation of oxaloacetate and other citric acid cycle intermediates. Results of this study demonstrate that the rates of formation and metabolism of pyruvate are increased during exercise.
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23
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Patel VK, Venkatakrishna-Bhatt H. In vitro study of antimicrobial activity of adhatoda vasika Linn. (leaf extract) on gingival inflammation--a preliminary report. Indian J Med Sci 1984; 38:70-2. [PMID: 6511018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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24
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Patel VK, Venkatakrishna-Bhatt H. Cichorium intibus Linn. A novel herbal preparation as a gum massage, dentifrice, anti-inflammatory and antiplaque agent (review and applied study). Therapie 1983; 38:405-14. [PMID: 6648883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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25
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Patel VK, Venkatakrishna-Bhatt H. Influence of constituents of country liquor on the induced toxicity of some muscle relaxants in mice and phrenic nerve diaphragm preparations of rats: a preliminary report. Ind Health 1980; 18:215-216. [PMID: 7251403 DOI: 10.2486/indhealth.18.215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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26
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Abstract
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.
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27
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Goebel HH, Zeman W, Patel VK, Pullarkat RK, Lenard HG. On the ultrastructural diversity and essence of residual bodies in neuronal ceroid-lipofuscinosis. Mech Ageing Dev 1979; 10:53-70. [PMID: 449423 DOI: 10.1016/0047-6374(79)90070-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
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.
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Abstract
Leukocyte glycerolipid fatty acid compositions were determined in four patients of juvenile form of neuronal ceroid-lipofuscinosis (Battens disease), their parents and age-matched controls. A 54 to 93% reduction in docosahexaenoic acid (22:6, n-3) was noted in patient leukocytes. The parents also showed reduction in docosahexaenoic acid content, but to a lesser degree. The levels of linolenic family (n-6) polyunsaturated fatty acids were unchanged suggesting that the metabolic defect in this disease is specific to the linolenic family (n-3) of fatty acids.
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Patel NB, Jindal MN, Patel VK. Study of some newly synthesized glutarimide compounds on skeletal muscle. Indian J Med Res 1977; 66:310-6. [PMID: 924603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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30
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Sepping P, Wood W, Bellamy C, Bridges PK, O'Gormann P, Bartlett JR, Patel VK. Studies of endocrine activity, plasma tryptophan and catecholamine excretion on psychosurgical patients. Acta Psychiatr Scand 1977; 56:1-14. [PMID: 331873 DOI: 10.1111/j.1600-0447.1977.tb06657.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The Geoffrey Knight Psychosurgical Unit admits patients on a regular basis and thus offers special opportunities for studying severely ill psychiatric cases, all having one particular treatment under relatively controlled conditions. The opportunity has been taken to repeat various metabolic studies previously reported to be abnormal in some psychiatric illnesses. In the present investigation several measures of endocrinological activity were studied, as was plasma tryptophan, both free and bound. None of these data confirmed reports of abnormalities and neither did the values found at operation help to predict clinical outcome 1 year later, which was another possibility. Urinary catecholamines were also measured and 2 weeks after operation. Male patients, regardless of diagnosis, showed a mean increase in adrenaline output after operation compared with the pre-operative value and this was significantly different from the females, who showed a small mean decrease. The depressed patients showed a significant reduction in noradrenaline excretion after operation compared with before operation and this trend was enhanced in those of good outcome at 1 year, the difference from those who responded poorly being significant. It could be that the ventromedial lesion that is produced alters noradrenaline metabolism or autonomic activity in depression and this possibility merits further study.
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Patel NB, Jindal MN, Patel VK. A preliminary report on the antiarrhythmic action of some newly synthesized glutarimide compounds. Indian J Physiol Pharmacol 1976; 20:172-6. [PMID: 977087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
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.
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Gandhi IC, Jindal MN, Patel VK. Mechaism of neuromuscular blockade with some antiepileptic drugs. Arzneimittelforschung 1976; 26:258-61. [PMID: 132942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Effects of four antiepileptic drugs, viz., diphenylhydantoin, trimethadione, phenobarbitone and ethosuximide, were studied on different in vitro and in vivo skeletal muscle preparations which consisted of frog rectus, rat phrenic nerve diaphragm and cat gastrocnemius sciatic nerve preparations. A dose related blockade of neuromuscular transmission was seen with all the compounds tested. The blockade was mainly confined to the neuromuscular junction, although direct stimulation of muscle was slightly affected. The blockade was partially antagonized by physostigmine, adrenaline, succinylcholine, choline, tetraethylammonium and KCl and was additive to that due to tubocurarine. Moreover, the drugs were found to possess moderate local anaesthetic activity. The blockade was therefore considered to be partly due to curariform activity and partly due to their local anaesthetic activity.
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33
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Jindal MN, Patel VK, Patel NB, Patel VA. Effect of methylated xanthines on skeletal muscle. Indian J Med Res 1976; 64:41-7. [PMID: 1270100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
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34
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Abstract
Ethanol was administered chronically for 14 days to male Sprague-Dawley rats. Day 15 was ethanol-free. On day 16 the rats received 25 mg of thiopental per kilogram (intravenously). One minute after the injection, the ethanol-treated rats showed lower blood levels of thiopental and higher liver levels of the drug than control rats given sucrose in place of ethanol. Samples of blood drawn 5 and 10 min after injection showed no significant difference in thiopental levels between the ethanol and control groups. The ethanol-treated group slept for a significantly shorter period of time. It is concluded that chronic ethanol consumption for 14 days decreases the pharmacological effects of thiopental and alters its initial distribution in the body.
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Jindal MN, Shah UH, Patel VK, Kelkar VV. A study of some beta-adrenoceptor blocking agents on skeletal muscle. Arzneimittelforschung 1975; 25:52-5. [PMID: 238544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The effect of three recently introduced beta-adrenoceptor blockers practolol, USVC 6524 and Inpea was studied on various skeletal muscle preparations. Practoloo, USVC 6524 and Inpea produced a dose related inhibition of acetylcholine induced contractions of rectus abdominis muscle of frog. These drugs also blocked neuromuscular transmission when tested on in vitro rat phrenic nerve diaphragm preparation; the blockade was partially reversed by physotigmine, KCl and adrenaline and was potentiated by d-tubocurarine. In gastrocnemius sciatic muscle-nerve preparation only Inpea exhibited neuromuscular blocking activity, while practolol and USVC 6524 did not show any effect up to a dose of 10 mg/kg (intraarterially). The apparent discrepancies between the results of in vitro and in vivo experiments could not be adequately explained. It has been discussed that the neuromuscular blockade caused by presently investigated beta-adrenoceptor blocking agents is essentially due to curare-like activity and to a small extent may be due to local anaesthetic activity.
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Shah UH, Jindal MN, Patel VK, Kelkar VV. Central actions of some beta-adrenoceptor blocking agents. Arzneimittelforschung 1974; 24:1581-4. [PMID: 4154760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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37
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Patel VK, Gohil KS. A brief review on pharmacotherapeutics of commonly used dental protective and dressings. News Bull Indian Dent Assoc 1974; 5:36-40. [PMID: 4530252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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38
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Patel VK, Jindal MN, Kelkar VV. In vivo study of mechanism of propranolol-induced blockade or neuromuscular transmission. Indian J Physiol Pharmacol 1974; 18:126-8. [PMID: 4370094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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39
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Jindal MN, Kelkar VV, Patel VK. The antagonism of the local anaesthetic activity and of acute toxicity of propranolol and pronethalol by -adrenergic blocking agents. Arch Int Pharmacodyn Ther 1972; 195:57-63. [PMID: 4400902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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40
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Patel VK, Awen CF. Benign lymphoid polyposis of ileum: three cases and a review of the literature. Can J Surg 1971; 14:402-5. [PMID: 5150187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
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41
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Washkuhn RJ, Patel VK, Robinson JR. Linear free energy models for ester solvolysis with a critical examination of the alcohol and phenol dissociation model. J Pharm Sci 1971; 60:736-44. [PMID: 5125774 DOI: 10.1002/jps.2600600516] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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42
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Abstract
Abstract
MJ 1999 [4-(isopropylamino-1-hydroxyethyl)methanesulphonanilide hydrochloride] produced a dose-related blockade of indirectly evoked twitches of the rat diaphragm, without materially altering the effects of direct stimulation. The magnitude of blockade was comparable whether the indirect stimulation was at 1/s or 1/20 s. The blockade was less pronounced at 25° than at 34°. The blockade was antagonized by neostigmine, potassium chloride, succinyl-choline, tetraethylammonium, adrenaline, isoprenaline and, to some extent, by noradrenaline. Blockade by MJ 1999 was additive to that due to tubocurarine; large concentrations of yohimbine, tolazoline, phenoxybenzamine and dihydroergotamine quickly antagonized MJ 1999 blockade. Small concentrations of adrenaline, isoprenaline, tolazoline or yohimbine prevented MJ 1999 blockade. MJ 1999 had no effect on nerve conduction. It is proposed that MJ 1999 has a two-fold mode of action at the neuromuscular junction; a curare-like effect and an action on β-receptors.
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