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1.
mBio ; : e0072724, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38975793

RESUMO

Toxoplasma gondii, the causative agent of toxoplasmosis, is an obligate intracellular parasite that infects warm-blooded vertebrates across the world. In humans, seropositivity rates of T. gondii range from 10% to 90% across communities. Despite its prevalence, few studies address how T. gondii infection changes the metabolism of host cells. In this study, we investigate how T. gondii manipulates the host cell metabolic environment by monitoring the metabolic response over time using noninvasive autofluorescence lifetime imaging of single cells, metabolite analysis, extracellular flux analysis, and reactive oxygen species (ROS) production. Autofluorescence lifetime imaging indicates that infected host cells become more oxidized and have an increased proportion of bound NAD(P)H compared to uninfected controls. Over time, infected cells also show decreases in levels of intracellular glucose and lactate, increases in oxygen consumption, and variability in ROS production. We further examined changes associated with the pre-invasion "kiss and spit" process using autofluorescence lifetime imaging, which also showed a more oxidized host cell with an increased proportion of bound NAD(P)H over 48 hours compared to uninfected controls, suggesting that metabolic changes in host cells are induced by T. gondii kiss and spit even without invasion.IMPORTANCEThis study sheds light on previously unexplored changes in host cell metabolism induced by T. gondii infection using noninvasive, label-free autofluorescence imaging. In this study, we use optical metabolic imaging (OMI) to measure the optical redox ratio (ORR) in conjunction with fluorescence lifetime imaging microscopy (FLIM) to noninvasively monitor single host cell response to T. gondii infection over 48 hours. Collectively, our results affirm the value of using autofluorescence lifetime imaging to noninvasively monitor metabolic changes in host cells over the time course of a microbial infection. Understanding this metabolic relationship between the host cell and the parasite could uncover new treatment and prevention options for T. gondii infections worldwide.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38910185

RESUMO

An extinction of incoming solar radiation is taking place by absorption and scattering by dust, water droplets, and gaseous molecules. Such phenomena are responsible for altering meteorological variables. In the present study, temporal analysis of the aerosol optical thickness (AOT) and black carbon (BC) surface mass concentration was undertaken using an ozone monitoring instrument (OMI) and modern-era retrospective analysis for research and applications, version 2 (MERRA-2) satellite from the year 2018 to 2022. The study was mainly focused on the western states of India which are Rajasthan, Gujarat, and Maharashtra. The correlation of AOT and BC surface mass concentration with near-surface temperature (2m above ground level) was analyzed. BC and temperature shows strong negative correlation as BC is known for its absorption of radiation. It accumulates in the atmosphere and contributes to atmospheric warming while simultaneously bringing down the near-surface air temperature due to the reduced sunlight reaching the ground. Also, seasonal analysis was conducted for winter, summer, monsoon, and post-monsoon, which shows the higher values of AOT in monsoon; however, seasonal average BC surface mass concentration was found high in winter in each year for all three states. AERONET data from Jaipur, Rajasthan, and Pune, Maharashtra for the year 2021 was used to further evaluate the AOT generated from OMI. The results demonstrated a significant connection, with R2 values of 0.62 and 0.69, respectively. The temperature retrieved from MERRA-2 was also validated with ground truth data of the Continuous Ambient Air Quality Monitoring Station (CAAQMS) at both stations showing high agreement with R2 > 0.70.

3.
Ageing Res Rev ; 99: 102396, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38942199

RESUMO

Lithium therapy received approval during the 1970s, and it has been used for its antidepressant, antimanic, and anti-suicidal effects for acute and long-term prophylaxis and treatment of bipolar disorder (BPD). These properties have been well established; however, the molecular and cellular mechanisms remain controversial. In the past few years, many studies demonstrated that at the cellular level, lithium acts as a regulator of neurogenesis, aging, and Ca2+ homeostasis. At the molecular level, lithium modulates aging by inhibiting glycogen synthase kinase-3ß (GSK-3ß), and the phosphatidylinositol (PI) cycle; latter, lithium specifically inhibits inositol production, acting as a non-competitive inhibitor of inositol monophosphatase (IMPase). Mitochondria and peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) have been related to lithium activity, and its regulation is mediated by GSK-3ß degradation and inhibition. Lithium also impacts Ca2+ homeostasis in the mitochondria modulating the function of the lithium-permeable mitochondrial Na+-Ca2+exchanger (NCLX), affecting Ca2+ efflux from the mitochondrial matrix to the endoplasmic reticulum (ER). A close relationship between the protease Omi, GSK-3ß, and PGC-1α has also been established. The purpose of this review is to summarize some of the intracellular mechanisms related to lithium activity and how, through them, neuronal aging could be controlled.


Assuntos
Senescência Celular , Compostos de Lítio , Neurônios , Neurônios/efeitos dos fármacos , Compostos de Lítio/farmacologia , Fármacos Neuroprotetores/farmacologia , Enzimas/metabolismo , Inositol/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Cálcio/metabolismo , Humanos , Animais , Senescência Celular/efeitos dos fármacos
4.
Int J Mol Sci ; 25(3)2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38338855

RESUMO

Systemic chronic inflammation (SCI) due to intrinsic immune over-activation is an important factor in the development of many noninfectious chronic diseases, such as neurodegenerative diseases and diabetes mellitus. Among these immune responses, macrophages are extensively involved in the regulation of inflammatory responses by virtue of their polarization plasticity; thus, dysregulation of macrophage polarization direction is one of the potential causes of the generation and maintenance of SCI. High-temperature demand protein A2 (HtrA2/Omi) is an important regulator of mitochondrial quality control, not only participating in the degradation of mis-accumulated proteins in the mitochondrial unfolded protein response (UPRmt) to maintain normal mitochondrial function through its enzymatic activity, but also participating in the regulation of mitochondrial dynamics-related protein interactions to maintain mitochondrial morphology. Recent studies have also reported the involvement of HtrA2/Omi as a novel inflammatory mediator in the regulation of the inflammatory response. HtrA2/Omi regulates the inflammatory response in BMDM by controlling TRAF2 stabilization in a collagen-induced arthritis mouse model; the lack of HtrA2 ameliorates pro-inflammatory cytokine expression in macrophages. In this review, we summarize the mechanisms by which HtrA2/Omi proteins are involved in macrophage polarization remodeling by influencing macrophage energy metabolism reprogramming through the regulation of inflammatory signaling pathways and mitochondrial quality control, elucidating the roles played by HtrA2/Omi proteins in inflammatory responses. In conclusion, interfering with HtrA2/Omi may become an important entry point for regulating macrophage polarization, providing new research space for developing HtrA2/Omi-based therapies for SCI.


Assuntos
Serina Peptidase 2 de Requerimento de Alta Temperatura A , Inflamação , Macrófagos , Mitocôndrias , Animais , Camundongos , Apoptose , Serina Peptidase 2 de Requerimento de Alta Temperatura A/metabolismo , Inflamação/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Macrófagos/metabolismo
5.
Environ Monit Assess ; 196(3): 323, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38421451

RESUMO

This study aims to generate a satellite-based qualitative emission source characterization for the heavily polluted eastern part of China in the 2010-2016 time period. The applied source identification technique relies on satellite-based NOx and SO2 emission estimates by OMI, their SO2:NOx ratio, and the MIX anthropogenic emission inventory to distinguish emissions from different emission categories (urban, industrial, natural) and characterize the dominant source per 0.25° × 0.25° grid cell in East China. Overall, we find good agreement between the satellite- and emission inventory-based spatiotemporal distribution and characterization of the dominant emission sources in East China in 2010-2016. In 2010, the satellite measurements suggest an emission distribution less dominated by industrial areas, a somewhat larger role for urban/transportation areas and agricultural activities, and more natural emissions in the southern part compared to the bottom-up emission categorization. In 2016, more than half of the classified emission categories over East China have remained the same. At the same time, there is a notable increase of agricultural lands and decrease of areas dominated by industry/transportation in 2016, suggestive of an overall decrease in heavy air pollution in East China over the course of 7 years. This is likely attributed to the sustained efforts of the Chinese government to drastically improve the air quality, especially since 2013 when the National Air Pollution Prevention and Control Action Plan was enacted. However, signs of urban expansion (urbanization) and rural-urban migration ("Go West" motion) stemmed from China's rapid economic growth and labour demand are evident; escalating industrialization (even with cleaner means) and the urban population growth in East China resulted in stronger emissions from sources representing consumption and transportation which are strongly related to NO2 and PM10 pollution (rather than SO2) and are directly influenced by the population size. This resulted to a shift of the emissions from the east mainly to the north and northwest of East China. Overall, although the effectiveness of the Chinese environmental control policies has been successful, the air pollution problem remains an important concern.


Assuntos
Poluição do Ar , Monitoramento Ambiental , Poluição Ambiental , Poluição do Ar/prevenção & controle , Agricultura , China
6.
Environ Monit Assess ; 196(2): 106, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38168710

RESUMO

The spatial and temporal dynamics of daily ultraviolet index (UVI) for a period of 18 years (2004-2022) over the Indian state of Kerala were statistically characterised in the study. The UVI measurements used for the study were derived from the ultraviolet-B (UVB) irradiance measured by the Ozone Monitoring Instrument (OMI) of the AURA satellite and classified into different severity levels for analysis. Basic statistics of daily, monthly and seasonal UVI as well as Mann-Kendall (MK) statistical trend characteristics and the rate of change of daily UVI using Theil-Sen's slope test were also evaluated. A higher variability of UVI characteristics was observed in the Kerala region, and more than 79% of the measurements fell into the categories of very high and extreme UVI values, which suggests the need of implementation of appropriate measures to reduce health risks. Although the UVI measured during the study period shows a slight decrease, most of the data show a seasonal variation with undulating low and peak values. Higher UVI are observed during the months of March, April and September. The region also has higher UVI during the southwest monsoon (SWM) and summer seasons. Although Kerala region as a single whole unit, UVI show a non-significant decreasing trend (-0.83), the MK test revealed the increasing and decreasing trends of UVI ranging from -1.96 to 0.41 facilitated the delineation of areas (domains) where UVI are increasing or decreasing. The domain of UVI increase occupies the central and southern (S) parts, and the domains of decrease cover the northern (N) and S parts of the Kerala region. The rate of change of daily UVI in domain of increase and decrease shows an average rate of 0.34 × 10-5 day-1 and -2 × 10-5 day-1, respectively. The parameters (rainfall, air temperature, cloud optical depth (COD) and solar zenith angle (SZA)) that affect the strength of UV rays reaching the surface indicate that a cloud-free atmosphere or low thickness clouds prevails in the Kerala region. Overall, the study results indicate the need for regular monitoring of UVI in the study area and also suggest appropriate campaigns to disseminate information and precautions for prolonged UVI exposure to reduce the adverse health effects, since the study area has a high population density.


Assuntos
Ozônio , Ozônio/análise , Tecnologia de Sensoriamento Remoto , Monitoramento Ambiental , Raios Ultravioleta , Estações do Ano , Índia
7.
Heliyon ; 9(12): e22825, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38125542

RESUMO

In this paper, the Gaussian optical properties and the first- and third-order isotropic and anisotropic chromatic aberrations of the Glaser magnetic lens have been derived analytically and then calculated numerically based on two methods: the differential-algebraic DA and the electron optical aberration integrals. These coefficients have been recalculated for object magnetic immersion OMI. The expressions of chromatic aberration coefficients with the inclusion of the OMI effect of round electron lenses were not published in the literature until the present work. The numerical results of high-order chromatic aberration coefficients of Glaser magnetic lenses calculated using the DA method are shown to be in excellent agreement with those calculated using the integral aberration method and with the minor relative errors of order (10-7- 10-8), indicating that all the formulas for the chromatic aberration coefficients are entirely correct. For this purpose, COSY INFINITY 10 and Mathematica 11 were used, and both proved to be excellent computer programs for this work.

8.
Sci Total Environ ; 904: 166693, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37657553

RESUMO

Remote sensing data from the Ozone Monitoring Instrument (OMI) and the TROPOspheric Monitoring Instrument (TROPOMI) play important roles in estimating surface nitrogen dioxide (NO2), but few studies have compared their differences for application in surface NO2 reconstruction. This study aims to explore the effectiveness of incorporating the tropospheric NO2 vertical column density (VCD) from OMI and TROPOMI (hereafter referred to as OMI and TROPOMI, respectively, for conciseness) for deriving surface NO2 and to apply the resulting data to revisit the spatiotemporal variations in surface NO2 for Beijing over the 2005-2020 period during which there were significant reductions in nitrogen oxide emissions. In the OMI versus TROPOMI performance comparison, the cross-validation R2 values were 0.73 and 0.72, respectively, at 1 km resolution and 0.69 for both at 100 m resolution. The comparisons between satellite data sources indicate that even though TROPOMI has a finer resolution it does not improve upon OMI for deriving surface NO2 at 1 km resolution, especially for analyzing long-term trends. In light of the comparison results, we used a hybrid approach based on machine learning to derive the spatiotemporal distribution of surface NO2 during 2005-2020 based on OMI. We had novel, independent passive sampling data collected weekly from July to September of 2008 for hindcasting validation and found a spatiotemporal R2 of 0.46 (RMSE = 7.0 ppb). Regarding the long-term trend of surface NO2, the level in 2008 was obviously lower than that in 2007 and 2009, as expected, which was attributed to pollution restrictions during the Olympic Games. The NO2 level started to steadily decline from 2015 and fell below 2008's level after 2017. Based on OMI, a long-term and fine-resolution surface NO2 dataset was developed for Beijing to support future environmental management questions and epidemiological research.

9.
Huan Jing Ke Xue ; 44(9): 4799-4808, 2023 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-37699799

RESUMO

Based on ambient air quality data, meteorological observation data, and satellite remote sensing data, the temporal and spatial variations in ozone (O3) pollution, the sensitivity of O3, and its relationship with meteorological factors in Hainan Island were analyzed in this study. The results showed that the maximum daily 8-h moving mean (O3-8h) in western and northern cities in Hainan Island was higher than that in the central, eastern, and southern cities. O3-8h was the highest in 2015, and O3-8h exceeding the standard proportion was the largest in 2019. In addition, O3-8h was positively correlated with average temperature (P<0.1), sunshine duration (P<0.01), total solar radiation (P<0.01), atmospheric pressure, and average wind speed and was negatively correlated with precipitation (P<0.05) and relative humidity. The satellite remote sensing data showed that the tropospheric NO2 column concentration (NO2-OMI) and HCHO column concentration (HCHO-OMI) displayed opposite trends in Hainan Island from 2015 to 2020. Compared with those in 2015, NO2-OMI increased by 7.74% and HCHO-OMI decreased by 10.2% in 2020. Moreover, Hainan Island belongs to the NOx control area, and the FNR value exhibited a fluctuating downward trend in the past 6 years, with a trend coefficient and climatic trend rate of -0.514 and -0.123 a-1, respectively. A strong correlation was observed between meteorological factors and the FNR value of Hainan Island.

10.
Huan Jing Ke Xue ; 44(8): 4220-4230, 2023 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-37694617

RESUMO

The surface ozone (O3) spatiotemporal distribution, variations, and its causes in Ji'nan from 2015 to 2020 were revealed based on the air quality monitoring network data and satellite retrievals from the Ozone Monitoring Instrument (OMI). The results showed that the ozone concentration in Ji'nan gradually increased from 2015 to 2020. The annual 90th percentile of the daily maximum 8-h average (MDA8) O3(namely the annual evaluation value) and the MDA8 O3(April-September) increased by 4.8 µg·(m3·a)-1 and 3.8 µg·(m3·a)-1, respectively. The trend of the ozone levels in the high-concentration range increased faster than that in the low-concentration range. The MDA8 in June increased by 7.4 µg·(m3·a)-1, and the rate range of increases was 2.6-3.9 µg·(m3·a)-1 in the cool seasons (December-February); thus, the O3 control in winter cannot be ignored. It is apparent from the diurnal variations in ozone from 2015 to 2020 in April-September that the average ozone levels have risen in recent years. The growth rate in the daytime was higher than that at night. The capacity of photochemical production has been increasing, especially in recent years. Additionally, it is noteworthy that the peak time for ozone levels occurred approximately 1-2 h earlier. The disparity of ozone concentrations among different stations gradually decreased in recent years. Compared with that in 2015, the range of areas with high O3 concentrations in 2019-2020 was further expanded. The significant positive trends in MDA8-90th and MDA8 (April-September) were observed in 16.1% and 22.6% of the monitoring sites in Ji'nan (P<0.05), most of which were located in urban areas and the suburbs close to urban areas. The temporal and spatial changes in ozone in Jinan had been affected by the changes in VOCs and NOx emissions since 2015. Satellite remote sensing data from 2015 to 2020 revealed that the NO2 tropospheric columns (April-September) showed reductions of 20.6%, with a decreasing rate of 0.3×1015 mole·(cm2·a)-1, especially in the urban areas and suburbs. The detected variation trends of tropospheric HCHO were weak and insignificant, which suggested that the decrease in NOx emissions was much greater than the decrease in VOCs emissions, and the gap had become more obvious in the urban areas. With responses to precursor emissions, the chemical sensitivity of O3 formation had been changing. The VOCs-limited regimes continuously decreased, and the mixed NOx/VOCs-sensitive regimes and NOx-limited regimes increased. In general, such an extremely inappropriate control ratio of ozone precursor NOx/VOCs led to an overall trend of slow increasing fluctuations of O3 in Ji'nan. The findings clearly indicate that the reduction of VOCs in Ji'nan was far from sufficient, and strengthening the current control of VOCs emissions is an effective measure to control the growth trend of O3 pollution in Ji'nan in the near future, especially in urban and surrounding suburban areas.

11.
Cell Mol Life Sci ; 80(9): 258, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37594630

RESUMO

HtrA2/Omi is a mitochondrial serine protease with ascribed pro-apoptotic as well as pro-necroptotic functions. Here, we establish that HtrA2/Omi also controls parthanatos, a third modality of regulated cell death. Deletion of HtrA2/Omi protects cells from parthanatos while reconstitution with the protease restores the parthanatic death response. The effects of HtrA2/Omi on parthanatos are specific and cannot be recapitulated by manipulating other mitochondrial proteases such as PARL, LONP1 or PMPCA. HtrA2/Omi controls parthanatos in a manner mechanistically distinct from its action in apoptosis or necroptosis, i.e., not by cleaving cytosolic IAP proteins but rather exerting its effects without exiting mitochondria, and downstream of PARP-1, the first component of the parthanatic signaling cascade. Also, previously identified or candidate substrates of HtrA2/Omi such as PDXDC1, VPS4B or moesin are not cleaved and dispensable for parthanatos, whereas DBC-1 and stathmin are cleaved, and thus represent potential parthanatic downstream mediators of HtrA2/Omi. Moreover, mass-spectrometric screening for novel parthanatic substrates of HtrA2/Omi revealed that the induction of parthanatos does not cause a substantial proteolytic cleavage or major alterations in the abundance of mitochondrial proteins. Resolving these findings, reconstitution of HtrA2/Omi-deficient cells with a catalytically inactive HtrA2/Omi mutant restored their sensitivity against parthanatos to the same level as the protease-active HtrA2/Omi protein. Additionally, an inhibitor of HtrA2/Omi's protease activity did not confer protection against parthanatic cell death. Our results demonstrate that HtrA2/Omi controls parthanatos in a protease-independent manner, likely via novel, unanticipated functions as a scaffolding protein and an interaction with so far unknown mitochondrial proteins.


Assuntos
Parthanatos , Serina Proteases/genética , Necroptose , Serina Endopeptidases/genética , Proteínas Mitocondriais/genética
12.
Environ Sci Technol ; 57(30): 11134-11143, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37467360

RESUMO

Satellite remote sensing is a promising method of monitoring emissions that may be missing in inventories, but the accuracy of these estimates is often not clear. We demonstrate here a comprehensive evaluation of errors in anthropogenic sulfur dioxide (SO2) emission estimates from NASA's OMI point source catalog for the contiguous US by comparing emissions from the catalog with high-quality emission inventory data over different dimensions including size of individual sources, aggregate vs individual source errors, and potential bias in individual source estimates over time. For sources that are included in the catalog, we find that errors in aggregate (sum of error for all included sources) are relatively low. Errors for individual sources in any given year can be substantial, however, with over- or underestimates in terms of total error ranging from -80 to 110 kt (roughly 10-90th percentile). We find that these errors are not necessarily random over time and that there can be consistently positive or negative biases for individual sources. We did not find any overall statistical relationship between the degree of isolation of a source and bias, either at a 40 or 70 km scales. For a sub-set of sources where inventory emissions over a radius of 70 km around an OMI detection are larger than twice the emissions within 40 km, the OMI value is consistently overestimated. We find, as expected, that emission sources not included in the catalog are the largest aggregate source of difference between the satellite estimates and inventories, especially in more recent years where source emission magnitudes have been decreasing and note that trends in satellite detections do not necessarily track trends in total emissions. We find that the OMI-based SO2 emissions are accurate in aggregate, when summed over a number of sources, but must be interpreted more cautiously at the individual source level. Similar analyses would be valuable for other satellite emission estimates; however, in many cases, the appropriate high-quality reference data may need to be generated.

13.
Am J Transl Res ; 15(6): 4033-4044, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37434840

RESUMO

OBJECTIVE: This study aimed to analyze the role of mitochondrial Omi/HtrA2 signaling pathway in neuronal apoptosis in patients with cerebral hemorrhage (CH). METHODS: In this retrospective analysis, the clinical data of 60 patients with CH who received craniotomy or minimally invasive intracranial hematoma (MIIH) were included in the case group, which was sub-divided into a craniotomy group (n=22) and a minimally invasive group (n=38) depending on the type of surgery. The brain tissue specimens of the above patients were retained in the surgical specimen repository of Yuhuan Second People's Hospital. Another 15 normal brain tissue samples retained in the surgical specimen repository were included in the normal group. The expression levels of Omi/HtrA2, X-linked inhibitor of apoptosis protein (XIAP), poly-adenosine diphosphate-ribose polymerase (PARP), pro-caspase 3, and pro-caspase 9 were determined using Western blotting. RESULTS: The case group exhibited a higher proportion of neuronal apoptosis, higher expression levels of Omi/HtrA2, PARP, and pro-caspase 3 and 9, higher activities of caspase 3 and caspase 9 (P < 0.05), and lower XIAP expression (P < 0.05) in brain tissue than the normal group. The proportion of neuronal cell apoptosis in brain tissues was positively correlated with the expression of Omi/HtrA2, PARP, and pro-caspase 3 and pro-caspase 9 (r > 0, P < 0.05), and the activity of caspase 3 and caspase 9 was negatively correlated with XIAP expression (r < 0, P < 0.05). Compared with the craniotomy group, the minimally invasive group demonstrated higher efficacy and hematoma removal rate, shorter hematoma removal time, hematoma drainage time, operation time, and hospital stay, less intraoperative bleeding, and lower postoperative complication rates (P < 0.05). The minimally invasive group showed higher expression level of serum XIAP and lower levels of serum caspase 3 and caspase 9 than the craniotomy group (P < 0.05). CONCLUSIONS: Mitochondrial Omi/HtrA2 signaling pathway may be involved in neuronal apoptosis. MIIH has the advantages of high efficacy, high hematoma clearance rate, and few complications for the treatment of CH.

14.
Sci Total Environ ; 894: 165060, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37353029

RESUMO

Formaldehyde (HCHO) is an air pollutant that has a detrimental effect on human health and atmospheric environment. Until now, satellite observation has been increasingly a valuable source for monitoring the unconventional atmospheric pollutants due to the limited availability of ground-based HCHO data. Here, we used Ozone Monitoring Instrument (OMI) and the weather research and forecasting with chemistry (WRF-Chem) model to synergistically analyze the spatiotemporal variations of tropospheric HCHO in Beijing during 2009-2020, and the response of O3 to HCHO and NO2 in hotspots. We also discuss the multiple factors influencing the variation of HCHO and identify potential source area. The results indicated that HCHO column concentration is higher in eastern Beijing, and peaking in 2018 (16.68 × 1015 mol/cm2). O3 shows a good response to HCHO, with higher HCHO and NO2 photolysis leading to O3 increase in summer. In winter, decreasing HCHO and increasing NO2 inhibits the formation of O3. Transportation emissions contributed the most to HCHO, followed by the industrial sector, while residential sources have long-term effects. Isoprene produced by plants is one of the main sources of HCHO, whereas meteorological conditions can affect production efficiency. Biomass burning contributes less. Moreover, HCHO in Beijing is affected by the combined effects of local emission and external transport, and Hebei is the potential source area. This study reveals HCHO has a great accumulation potential in cities and highlights the dominant role of anthropogenic emissions, but also need to consider the influence of natural factors and regional transport.

15.
Cureus ; 15(5): e38708, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37292562

RESUMO

In addition to the well-known convex ST-segment elevation myocardial infarction (STEMI) pattern associated with acute occlusive myocardial infarction (OMI), there are other cases that are recognized as OMI without fulfilling the established characteristic STEMI criteria. Over one-fourth of the patients initially classified as having non-STEMI can be re-classified as having OMI by recognizing other STEMI equivalent patterns. We report a case of a 79-year-old man with multiple comorbidities who was brought to the ED by paramedics with a two-hour history of ongoing chest pain. During transport, the patient suffered a cardiac arrest associated with ventricular fibrillation (VF) that required electric defibrillation and active cardiopulmonary resuscitation. Upon ED arrival, the patient was unresponsive, with a heart rate of 150 beats/min and ECG evidence of wide-QRS tachycardia that was misinterpreted as ventricular tachycardia (VT). He was further managed with intravenous amiodarone, mechanical ventilation, sedation, and unsuccessful defibrillation therapy. Upon persistence of the wide-QRS tachycardia and clinical instability, the cardiology team was emergently consulted for bedside assistance. On further review of the ECG, a shark fin (SF) OMI pattern was identified, indicative of an extensive anterolateral OMI. A bedside echocardiogram revealed a severe left ventricular systolic dysfunction with marked anterolateral and apical akinesia. The patient underwent a successful percutaneous coronary intervention (PCI) to an ostial left anterior descending (LAD) culprit occlusion with hemodynamic support but ultimately died due to multiorgan failure and refractory ventricular arrhythmias. This case illustrates an infrequent OMI presentation (<1.5%) formed by the fusion of the QRS, ST-segment elevation, and T-wave resulting in a wide triangular waveform, giving the appearance of an SF that can also potentially lead to ECG misinterpretation as VT. It also highlights the importance of recognizing STEMI-equivalent ECG patterns to avoid delays in reperfusion therapy. The SF OMI pattern has also been associated with a large amount of ischemic myocardium (such as with left main or proximal LAD occlusion) with a higher mortality risk from cardiogenic shock and/or VF. This high-risk OMI pattern should lead to a more definite reperfusion treatment, such as primary PCI and the possible need for backup hemodynamic support.

16.
Harmful Algae ; 125: 102427, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37220979

RESUMO

Dinophysis acuminata, the main cause of shellfish harvesting bans in Europe, blooms in the Galician Rías (NW Spain) throughout the upwelling season (ca. March to September). Here we illustrate rapid changes in vertical and across ría-shelf distributions of diatoms and dinoflagellates (including D. acuminata vegetative and small cells) in Ría de Pontevedra (RP) and Ría de Vigo (RV) during transitions from spin-down to spin-up phases of upwelling cycles. A subniche approach based on a Within Outlying Mean Index (WitOMI) showed that under the transient environmental conditions met during the cruise, both vegetative and small cells of D. acuminata colonized the Ria and Mid-shelf subniches, exhibiting good tolerance and extremely high marginality, in particular the small cells. Bottom-up (abiotic) control overwhelmed biological constraints, and shelf waters became a more favourable environment than the Rías. Contrasting higher biotic constraints inside the Rías were found for the small cells, with a subniche possibly controlled by unsuitable physiological status (notwithstanding the higher density) of the vegetative cell population. Results here on behaviour (vertical positioning) and physiological traits (high tolerance but very specialized niche) of D. acuminata give new insights into the ability of this species to remain in the upwelling circulation system. Higher shelf-ría exchanges in the Ría (RP) with more dense and persistent D. acuminata blooms reveal the relevance of transient event-scales and species- and site-specific characteristics to the fate of these blooms. Earlier statements about simple linear relationships between average upwelling intensities and the recurrence of Harmful algae bloom (HAB) events in the Galician Rías Baixas are questioned.


Assuntos
Diatomáceas , Dinoflagellida , Proliferação Nociva de Algas , Europa (Continente) , Alimentos Marinhos
17.
Environ Monit Assess ; 195(6): 680, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37191765

RESUMO

COVID-19 lockdown has given us an opportunity to investigate the pollutant concentrations in response to the restricted anthropogenic activities. The atmospheric concentration levels of nitrogen dioxide (NO2), carbon monoxide (CO) and ozone (O3) have been analysed for the periods during the first wave of COVID-19 lockdown in 2020 (25th March-31st May 2020) and during the partial lockdowns due to second wave in 2021 (25th March-15th June 2021) across India. The trace gas measurements from Ozone Monitoring Instrument (OMI) and Atmosphere InfraRed Sounder (AIRS) satellites have been used. An overall decrease in the concentration of O3 (5-10%) and NO2 (20-40%) have been observed during the 2020 lockdown when compared with business as usual (BAU) period in 2019, 2018 and 2017. However, the CO concentration increased up to 10-25% especially in the central-west region. O3 and NO2 slightly increased or had no change in 2021 lockdown when compared with the BAU period, but CO showed a mixed variation prominently influenced by the biomass burning/forest fire activities. The changes in trace gas levels during 2020 lockdown have been predominantly due to the reduction in the anthropogenic activities, whereas in 2021, the changes have been mostly due to natural factors like meteorology and long-range transport, as the emission levels have been similar to that of BAU. Later phases of 2021 lockdown saw the dominant effect of rainfall events resulting in washout of pollutants. This study reveals that partial or local lockdowns have very less impact on reducing pollution levels on a regional scale as natural factors like atmospheric long-range transport and meteorology play deciding roles on their concentration levels.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Poluentes Ambientais , Ozônio , Humanos , COVID-19/epidemiologia , Poluição do Ar/análise , Poluentes Atmosféricos/análise , Dióxido de Nitrogênio/análise , Monitoramento Ambiental/métodos , Controle de Doenças Transmissíveis , Ozônio/análise , Poluentes Ambientais/análise , Material Particulado/análise
18.
Sci Total Environ ; 888: 164121, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37187386

RESUMO

Near-surface ozone pollution is becoming an increasingly serious air quality issue in China, especially in "2 + 26" cities (Beijing-Tianjin-Hebei and nearby cities). HN2 + 26 cities ("2 + 26" cities of Henan Province) are located in the south of "2 + 26" cities, with frequent and severe ozone pollution events in recent years. This study investigated the diurnal evolution characteristics of ozone formation sensitivity (OFS) of HN2 + 26 cities from May to September in 2021 by the innovative combination of Global Ozone Monitoring Experiment (GOME-2B) and Ozone Monitoring Instrument (OMI) satellite data, and assessed the impact of ozone pollution control measures (OPCMs) implemented from June 26 to July 1, 2021. The localized FNR (ratio of formaldehyde to nitrogen dioxide of satellite measurement) threshold (1.4-2.55) was established, and it was found that OFS in May-September 2021 was mainly in VOCs-limited regime in the morning (∼10:00), while transitional/NOx-limited regime in the afternoon (∼14:00). Three periods (before, during and after the OPCMs) were divided to evaluate the impact of OPCMs on OFS. It was indicated that OPCMs had no impact on the morning OFS, but had a significant impact on the afternoon OFS. Specifically, the OFS in two industrial cities Xinxiang (XX) and Zhengzhou (ZZ) shifted from transitional regime to NOx-limited regime after the OPCMs. We further investigated OFS differences between urban and suburban areas and found that OFS shift of XX only existed in urban areas, while that of ZZ existed in both urban and suburban areas. We compared their measures and found that it is effective to take hierarchical control measures on different levels of ozone pollution days to alleviate ozone pollution. This study provides an improved understanding of diurnal evolution characteristics of OFS and the impacts of OPCMs on it, which will provide a theoretical basis for formulating more scientific ozone pollution control policies.

19.
Am J Emerg Med ; 69: 17-22, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37037160

RESUMO

BACKGROUND: Chest pain is a common presentation to the Emergency Department (ED) with roughly 6 million visits a year. The primary diagnostic modality for the identification of acute coronary syndrome (ACS) is the electrocardiogram (ECG), which is used to screen for electrocardiographic findings representing acute coronary occlusion. It is known that the ischemia generated by an acutely occluded coronary vessel generates a wall motion abnormality which can be visualized by echocardiogram; however, emergency physician-performed focused cardiac ultrasound (FOCUS) currently does not have a formal role in the diagnosis of OMI within the emergency department. PURPOSE: We sought to define the characteristics of FOCUS performed by emergency physicians of variable training levels in the identification of RWMA in patients presenting to the emergency department with high suspicion for ACS before undergoing cardiac catheterization or formal echocardiography. We also explored whether RWMA was associated with OMI in these patients. METHODS: We performed a structured, retrospective review of adult patients presenting to a large, academic, tertiary care center with suspected ACS from July 1st, 2019, and October 24th, 2020. Patients were included if they underwent FOCUS in the ED during the time-period above for suspected ACS looking for RWMA and FOCUS images were stored and reviewable in our middleware software. The primary outcome was the accuracy, sensitivity, and specificity of FOCUS compared to formal echocardiography for the detection of RWMA. Secondary outcomes were sensitivity of FOCUS compared to formal echocardiography for detection of RWMA in patients with and without cardiac catheterization proven OMI and sensitivity and specificity of FOCUS operators based on training. RESULTS: FOCUS for RWMA performed by emergency physicians had a sensitivity of 94% (95% CI, 82-98), specificity 35% (95% CI, 15-61), and overall accuracy of 78% (95% CI, 66-87). Of all subjects, 82% underwent urgent or emergency coronary angiography, of which 71% had OMI at the time of coronary angiography of the procedure. FOCUS identified RWMA in 87% of patients with coronary angiography proven OMI. Residents (PGY-1 - PGY-3) (n = 31) were able to detect RWMA with a sensitivity of 86% (95% CI, 64-96), a specificity of 56% (95% CI, 23-85%), and an accuracy of 77 (95% CI, 58-90%). Emergency ultrasound fellows and attendings (n = 34) were able to detect RWMA with a sensitivity of 85% (95% CI, 64-95%), a specificity of 75% (95% CI, 36-96%), and an accuracy of 82% (95% CI, 65-93%). CONCLUSIONS: Our retrospective study concludes FOCUS performed by emergency physicians may be used to detect RWMA in patients with high concern for acute coronary syndrome. This may have its greatest utility in patients presenting without STEMI where the ECG is felt to be equivocal, but the clinician has high concern for OMI, in which the presence of RWMA might result in emergent cath lab activation, though this requires further study. The presence of RWMA in such cases may help to rule in OMI as a cause; however, the absence of RWMA should exclude OMI. Further research is necessary to confirm these findings.


Assuntos
Síndrome Coronariana Aguda , Adulto , Humanos , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/diagnóstico por imagem , Estudos Retrospectivos , Ecocardiografia/métodos , Dor no Peito/etiologia , Serviço Hospitalar de Emergência
20.
Med Oncol ; 40(3): 103, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36811793

RESUMO

Colorectal cancer is the most common tumor of the gastrointestinal system. The conventional treatment options for colorectal cancer are troublesome for both patients and clinicians. Recently, mesenchymal stem cells (MSCs) have been the novel focus for cell therapy due to their migration to tumor sites. In this study, the apoptotic effect of MSCs on colorectal cancer cell lines has been aimed. HCT-116 and HT-29 were selected as the colorectal cancer cell lines. Human umbilical cord blood and Wharton's jelly were used as mesenchymal stem cell sources. To discriminate against the apoptotic effect of MSC on cancer, we also used peripheral blood mononuclear cells (PBMC) as a healthy control group. Cord blood-MSC and PBMC were obtained by ficoll-paque density gradient, and Wharton's jelly-MSC by explant method. Transwell co-culture systems were used as cancer cells or PBMC/MSCs at ratios of 1/5 and 1/10, with incubation times of 24 h and 72 h. The Annexin V/PI-FITC-based apoptosis assay was performed by flow cytometry. Caspase-3 and HTRA2/Omi proteins were measured by ELISA. For both ratios in both cancer cells, it was found that the apoptotic effect of Wharton's jelly-MSC was significantly higher in 72-h incubations (p < 0.006), whereas the effect of cord blood mesenchymal stem cell in 24-h incubations were higher (p < 0.007). In this study, we showed that human cord blood and tissue-derived MSCs treatment led to colorectal cancers to apoptosis. We anticipate that further in vivo studies may shed light on the apoptotic effect of MSC.


Assuntos
Neoplasias Colorretais , Células-Tronco Mesenquimais , Humanos , Cordão Umbilical/metabolismo , Diferenciação Celular , Leucócitos Mononucleares , Células Cultivadas , Neoplasias Colorretais/metabolismo
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