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1.
Nat Commun ; 15(1): 3517, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664406

RESUMEN

The oxidative potential (OP) of particulate matter (PM) is a major driver of PM-associated health effects. In India, the emission sources defining PM-OP, and their local/regional nature, are yet to be established. Here, to address this gap we determine the geographical origin, sources of PM, and its OP at five Indo-Gangetic Plain sites inside and outside Delhi. Our findings reveal that although uniformly high PM concentrations are recorded across the entire region, local emission sources and formation processes dominate PM pollution. Specifically, ammonium chloride, and organic aerosols (OA) from traffic exhaust, residential heating, and oxidation of unsaturated vapors from fossil fuels are the dominant PM sources inside Delhi. Ammonium sulfate and nitrate, and secondary OA from biomass burning vapors, are produced outside Delhi. Nevertheless, PM-OP is overwhelmingly driven by OA from incomplete combustion of biomass and fossil fuels, including traffic. These findings suggest that addressing local inefficient combustion processes can effectively mitigate PM health exposure in northern India.

2.
Cancer Med ; 12(13): 14225-14251, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37191030

RESUMEN

BACKGROUND: Percutaneous thermal ablation has become the preferred therapeutic treatment option for liver cancers that cannot be resected. Since ablative zone tissue changes over time, it becomes challenging to determine therapy effectiveness over an extended period. Thus, an immediate post-procedural evaluation of the ablation zone is crucial, as it could influence the need for a second-look treatment or follow-up plan. Assessing treatment response immediately after ablation is essential to attain favorable outcomes. This study examines the efficacy of image fusion strategies immediately post-ablation in liver neoplasms to determine therapeutic response. METHODOLOGY: A comprehensive systematic search using PRISMA methodology was conducted using EMBASE, MEDLINE (via PUBMED), and Cochrane Library Central Registry electronic databases to identify articles that assessed the immediate post-ablation response in malignant hepatic tumors with fusion imaging (FI) systems. The data were retrieved on relevant clinical characteristics, including population demographics, pre-intervention clinical history, lesion characteristics, and intervention type. For the outcome metrics, variables such as average fusion time, intervention metrics, technical success rate, ablative safety margin, supplementary ablation rate, technical efficacy rate, LTP rates, and reported complications were extracted. RESULTS: Twenty-two studies were included for review after fulfilling the study eligibility criteria. FI's immediate technical success rate ranged from 81.3% to 100% in 17/22 studies. In 16/22 studies, the ablative safety margin was assessed immediately after ablation. Supplementary ablation was performed in 9 studies following immediate evaluation by FI. In 15/22 studies, the technical effectiveness rates during the first follow-up varied from 89.3% to 100%. CONCLUSION: Based on the studies included, we found that FI can accurately determine the immediate therapeutic response in liver cancer ablation image fusion and could be a feasible intraprocedural tool for determining short-term post-ablation outcomes in unresectable liver neoplasms. There are some technical challenges that limit the widespread adoption of FI techniques. Large-scale randomized trials are warranted to improve on existing protocols. Future research should emphasize improving FI's technological capabilities and clinical applicability to a broader range of tumor types and ablation procedures.


Asunto(s)
Técnicas de Ablación , Carcinoma Hepatocelular , Ablación por Catéter , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/patología , Carcinoma Hepatocelular/cirugía , Técnicas de Ablación/efectos adversos , Técnicas de Ablación/métodos , Tomografía Computarizada por Rayos X/métodos , Ablación por Catéter/efectos adversos , Ablación por Catéter/métodos
3.
Nat Geosci ; 15(3): 196-202, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35341076

RESUMEN

Aerosols play an important yet uncertain role in modulating the radiation balance of the sensitive Arctic atmosphere. Organic aerosol is one of the most abundant, yet least understood, fractions of the Arctic aerosol mass. Here we use data from eight observatories that represent the entire Arctic to reveal the annual cycles in anthropogenic and biogenic sources of organic aerosol. We show that during winter, the organic aerosol in the Arctic is dominated by anthropogenic emissions, mainly from Eurasia, which consist of both direct combustion emissions and long-range transported, aged pollution. In summer, the decreasing anthropogenic pollution is replaced by natural emissions. These include marine secondary, biogenic secondary and primary biological emissions, which have the potential to be important to Arctic climate by modifying the cloud condensation nuclei properties and acting as ice-nucleating particles. Their source strength or atmospheric processing is sensitive to nutrient availability, solar radiation, temperature and snow cover. Our results provide a comprehensive understanding of the current pan-Arctic organic aerosol, which can be used to support modelling efforts that aim to quantify the climate impacts of emissions in this sensitive region.

4.
Int J Surg Protoc ; 25(1): 209-215, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34611571

RESUMEN

INTRODUCTION: Percutaneous thermal ablation is widely adopted as a curative treatment approach for unresectable liver neoplasms. Accurate immediate assessment of therapeutic response post-ablation is critical to achieve favourable outcomes. The conventional technique of side-by-side comparison of pre- and post-ablation scans is challenging and hence there is a need for improved methods, which will accurately evaluate the immediate post-therapeutic response. OBJECTIVES AND SIGNIFICANCE: This review summarizes the findings of studies investigating the feasibility and efficacy of the fusion imaging systems in the immediate post-operative assessment of the therapeutic response to thermal ablation in liver neoplasms. The findings could potentially empower the clinicians with updated knowledge of the state-of-the-art in the assessment of treatment response for unresectable liver neoplasms. METHODS AND ANALYSIS: A rapid review will be performed on publicly available major electronic databases to identify articles reporting the feasibility and efficacy of the fusion imaging systems in the immediate assessment of the therapeutic response to thermal ablation in liver neoplasms. The risk of bias and quality of articles will be assessed using the Cochrane risk of bias tool 2.0 and Newcastle Ottawa tool. ETHICS AND DISSEMINATION: Being a review, we do not anticipate the need for any approval from the Institutional Review Board. The outcomes of this study will be published in a peer-reviewed journal. HIGHLIGHTS: Evaluation of the therapeutic response in liver neoplasms immediately post-ablation is critical to achieve favourable patient outcomes. We will examine the feasibility and technical efficacy of different fusion imaging systems in assessing the immediate treatment response post-ablation. The findings are expected to guide the clinicians with updated knowledge on the state-of-the-art when assessing the immediate treatment response for unresectable liver neoplasms.

5.
Sci Total Environ ; 770: 145324, 2021 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-33736388

RESUMEN

National Capital Region (NCR) encompassing New Delhi is one of the most polluted urban metropolitan areas in the world. Real-time chemical characterization of fine particulate matter (PM1 and PM2.5) was carried out using three aerosol mass spectrometers, two aethalometers, and one single particle soot photometer (SP2) at two sites in Delhi (urban) and one site located ~40 km downwind of Delhi, during January-March 2018. The campaign mean PM2.5 (NR-PM2.5 + BC) concentrations at the two urban sites were 153.8 ± 109.4 µg.m-3 and 127.8 ± 83.2 µg.m-3, respectively, whereas PM1 (NR-PM1 + BC) was 72.3 ± 44.0 µg.m-3 at the downwind site. PM2.5 particles were composed mostly of organics (43-44)% followed by chloride (14-17)%, ammonium (9-11)%, nitrate (9%), sulfate (8-10)%, and black carbon (11-16)%, whereas PM1 particles were composed of 47% organics, 13% sulfate as well as ammonium, 11% nitrate as well as chloride, and 5% black carbon. Organic aerosol (OA) source apportionment was done using positive matrix factorization (PMF), solved using an advanced multi-linear engine (ME-2) model. Highly mass-resolved OA mass spectra at one urban and downwind site were factorized into three primary organic aerosol (POA) factors including one traffic-related and two solid-fuel combustion (SFC), and three oxidized OA (OOA) factors. Whereas unit mass resolution OA at the other urban site was factorized into two POA factors related to traffic and SFC, and one OOA factor. OOA constituted a majority of the total OA mass (45-55)% with maximum contribution during afternoon hours ~(70-80)%. Significant differences in the absolute OOA concentration between the two urban sites indicated the influence of local emissions on the oxidized OA formation. Similar PM chemical composition, diurnal and temporal variations at the three sites suggest similar type of sources affecting the particulate pollution in Delhi and adjoining cities, but variability in mass concentration suggest more local influence than regional.

6.
Environ Pollut ; 278: 116865, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33714061

RESUMEN

Characteristics and sources of ambient particle elements in urban Beijing were studied by hourly observations in two size fractions (PM10 and PM2.5) during November and December 2017 using an online multi-element analyzer. The reconstructed oxide concentrations of 24 elements (from Al to Pb) comprise an appreciable fraction of PM10 and PM2.5, accounting for 37% and 17%, respectively on average. We demonstrate the benefit of using high-time-resolution chemical speciation data in achieving robust source apportionment of the total elemental PM10 (PM10el) and elemental PM2.5 (PM2.5el) mass using positive matrix factorization (PMF). Biomass burning, coal combustion, secondary sulfate, industry, non-exhaust traffic and dust were identified in both size fractions (with varying relative concentrations), which accounted on average for 4%, 12%, 5%, 2%, 14%, and 63%, respectively to the total PM10el, and 14%, 35%, 21%, 6%, 12% and 12%, respectively to the total PM2.5el. Biomass burning and coal combustion exhibited higher concentrations during haze episodes of the heating season. In contrast, secondary sulfate and industry contributed more to haze episodes during the non-heating season. The fractional contribution of dust was mostly high during clean days, while the fractional non-exhaust traffic emission contribution was similar throughout the measurement period. The non-exhaust traffic emissions contributed locally, while the remaining sources were dominated by neighboring areas. Furthermore, trajectory analysis showed that the origin of the industrial sources roughly agreed with the locations of the main point sources. Overall, this work provides detailed information on the characteristics of the elements during different haze events during heating and non-heating seasons.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Contaminantes Atmosféricos/análisis , Beijing , Monitoreo del Ambiente , Material Particulado/análisis , Estaciones del Año , Emisiones de Vehículos/análisis
7.
Sci Total Environ ; 742: 140332, 2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-33167294

RESUMEN

Delhi, the capital of India, suffers from heavy local emissions as well as regional transport of air pollutants, resulting in severe aerosol loadings. To determine the sources of these pollutants, we have quantified the mass concentrations of 26 elements in airborne particles, measured by an online X-ray fluorescence spectrometer with time resolution between 30 min and 1 h. Measurements of PM10 and PM2.5 (particulate matter <10 µm and < 2.5 µm) were conducted during two consecutive winters (2018 and 2019) in Delhi. On average, 26 elements from Al to Pb made up ~25% and ~19% of the total PM10 mass (271 µg m-3 and 300 µg m-3) in 2018 and 2019, respectively. Nine different aerosol sources were identified during both winters using positive matrix factorization (PMF), including dust, non-exhaust, an S-rich factor, two solid fuel combustion (SFC) factors and four industrial/combustion factors related to plume events (Cr-Ni-Mn, Cu-Cd-Pb, Pb-Sn-Se and Cl-Br-Se). All factors were resolved in both size ranges (but varying relative concentrations), comprising the following contributions to the elemental PM10 mass (in % average for 2018 and 2019): Cl-Br-Se (41.5%, 36.9%), dust (27.6%, 28.7%), non-exhaust (16.2%, 13.7%), S-rich (6.9%, 9.2%), SFC1 + SFC2 (4%, 7%), Pb-Sn-Se (2.3%, 1.66%), Cu-Cd-Pb (0.67%, 2.2%) and Cr-Ni-Mn (0.57%, 0.47%). Most of these sources had the highest relative contributions during late night (22:00 local time (LT)) and early morning hours (between 03:00 to 08:00 LT), which is consistent with enhanced emissions into a shallow boundary layer. Modelling of airmass source geography revealed that the Pb-Sn-Se, Cl-Br-Se and SFC2 factors prevailed for northwest winds (Pakistan, Punjab, Haryana and Delhi), while the Cu-Cd-Pb and S-rich factors originated from east (Nepal and Uttar Pradesh) and the Cr-Ni-Mn factor from northeast (Uttar Pradesh). In contrast, SFC1, dust and non-exhaust were not associated with any specific wind direction.

8.
South Asian J Cancer ; 6(3): 125-128, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28975122

RESUMEN

CONTEXT: Biochemical changes occur in biological fluids and tissues of different types of malignancies. Tumor markers in serum, tissue, and other body fluids during neoplastic process are of clinical value in the management of patients with cancers. Serum alkaline phosphatase (ALP) activity is potentially a useful indicator for detection of malignancies, but its status in oral squamous cell carcinoma (OSCC) is less explored. AIMS: The aim of this study is to evaluate the serum level of ALP in OSCC patients and assess its relation with the clinicopathological features. SETTINGS AND DESIGN: A total of 175 participants (145 OSCC patients and 30 healthy controls) were included in the study. One hundred and forty-five patients with OSCC who underwent treatment at our institution were included to obtain the clinicopathological data. MATERIALS AND METHODS: Fasting blood ALP activity was evaluated using ALP assessment kit and biochemistry analyzer. STATISTICAL ANALYSIS USED: The data were analyzed by SPSS-21 software (SPSS Statistics for Windows, Version 21.0, Armonk, NY, USA), using t-test, Mann-Whitney U, and Kruskal-Wallis tests. RESULTS: Raised ALP was seen in 24% of OSCC patients. The mean ALP in OSCC was significantly higher than the control. ALP level in patients with advanced stage was significantly higher than with early stage. The serum ALP level in OSCC patients with bone involvement (BI) by local extension of tumor was significantly higher than without BI. CONCLUSION: ALP showed statistically significant differences in relation to tumor stages and BI. Hence, ALP could be useful in advanced stage disease for expressing the endurance of patient and tumor expansion. Elevated ALP in OSCC patients may indicate BI.

10.
J Investig Clin Dent ; 8(3)2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27157628

RESUMEN

OBJECTIVE: To assess whether the neutophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) before complete surgical staging will provide information on lymph node metastasis (LNM) in oral squamous cell carcinoma (OSCC) patients and to evaluate the relation of NLR and PLR with the various clinicopathologic characteristics. METHODS: The clinicopathological data and the preoperative complete blood investigation details were obtained from 68 OSCC patients who underwent surgical treatment. Receiver operating characteristics (ROC) curve analysis was used to evaluate cut-off, sensitivity, and specificity values for preoperative NLR and PLR in order to predict LNM. RESULTS: Lymph node involvement was detected in 24 (35%) patients. The best cut-off value for predicting LNM was 128.5 for the PLR, with 75% sensitivity and 70.45% specificity (P < 0.05). Fifty-five percent of patients had PLR ≤ 128.5 and 45% had PLR > 128.5. The PLR was higher in the lymph-node-positive group than in the negative group (147.63 ± 35.49 vs. 120.51 ± 42.5) (P < 0.05). There was an association between PLR cut-off and tumor stage. The best cut-off value for predicting LNM was 1.77 for NLR, with sensitivity of 87.5% and 25% specificity (P = 0.92). CONCLUSION: Preoperative PLR is directly associated with nodal involvement status of OSCC. Preoperative PLR is superior to NLR for predicting LNM in OSCC.


Asunto(s)
Plaquetas , Carcinoma de Células Escamosas/sangre , Carcinoma de Células Escamosas/secundario , Linfocitos , Neoplasias de la Boca/sangre , Neoplasias de la Boca/patología , Neutrófilos , Adulto , Anciano , Biomarcadores/sangre , Femenino , Humanos , Recuento de Leucocitos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Valor Predictivo de las Pruebas , Periodo Preoperatorio , Estudios Retrospectivos
11.
J Oral Maxillofac Pathol ; 19(2): 164-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26604491

RESUMEN

BACKGROUND: Secretor status may possibly be one of the factors in the etiopathogenesis of oral precancerous lesions and subsequently cancer. Studies have shown the relationship between the pathogenesis of disease and secretor status. They have made known that secretor status is a possible factor influencing disease status. Studies have revealed the association between blood groups and specific diseases. AIMS: To assess any association of ABO blood grouping with oral potentially malignant disorders (OPMDs) and to examine whether there is any difference in the saliva secretor status in the patients with OPMDs and healthy controls. MATERIALS AND METHODS: The study consisted of 90 subjects, with 45 patients assigned to two groups (a) Patients with potentially malignant disorders and (b) healthy controls. ABO blood grouping was done and 1 ml of unstimulated saliva was collected in a sterile test tube. The Wiener agglutination test was performed to analyze the secretor status in both the groups. Chi-square test and odd ratio were used to assess the relationship between ABO blood group and OPMDs. Chi-square test was performed to assess the relationship between secretor status and OPMDs. Probability level was fixed at <0.05. RESULTS: The results demonstrated a statistically significant relation between OPMDs and secretor status (P = 0.00). Eighty-seven percent of patients with OPMDs were nonsecretors, while in the control group sixteen percent of them were nonsecretors. There was no statistically significant relationship between ABO blood groups and OPMDs (P > 0.05). CONCLUSIONS: The study confirms the inability to secrete blood group antigens in the saliva of patients with OPMDs which could be regarded as a host risk factor. Results could not propose a relationship between ABO blood group and OPMDs.

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