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1.
Ann Card Anaesth ; 26(4): 411-417, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37861575

RESUMEN

Background: Maintaining a low left atrial pressure (LAP) in off-pump coronary artery bypass grafting (OPCAB) is desirable. This study was done to compare the effects of intravenous levosimendan or milrinone on LAP at different stages of OPCAB. Materials and Methods: After institutional ethics committee clearance, this two-arm double-blind randomized control trial was done in 44 adult patients with triple vessel coronary artery disease undergoing OPCAB at cardiac OT of IPGME&R, Kolkata. The patients were randomly allocated into two groups receiving intraoperative either levosimendan or milrinone. Pulmonary capillary wedge pressure (PCWP) was compared as the primary outcome parameter, whereas other echocardiographic and hemodynamic parameters were also assessed during six stages of OPCAB, that is, after sternotomy, proximal(s), left anterior descending artery (LAD), obtuse marginal (OM), posterior descending artery (PDA) grafting, and before sternal closure. Numerical parameters were compared using Student's unpaired two-tailed t-test. Results: PCWP was found to be significantly lower (P < 0.05) in the levosimendan group during proximal (P = 0.047), LAD (P = 0.018), OM (P < 0.0001), PDA grafting (P = 0.028), and before sternal closure (P = 0.015). Other parameters indicate LAP, that is, from mitral early diastolic inflow velocity to mitral annular early diastolic velocity ratio (E/e'), which indicated significantly lower LAP in levosimendan group during LAD, OM, and PDA grafting and before sternal closure. Conclusion: Levosimendan may be used as a primary inotrope in terms of better reduction in left atrial pressure during different stages of OPCAB, translating to a decrease in left ventricular end-diastolic pressure, therefore maintaining optimum coronary perfusion pressure, which is the primary goal of the surgery.


Asunto(s)
Puente de Arteria Coronaria Off-Pump , Milrinona , Adulto , Humanos , Simendán , Milrinona/farmacología , Milrinona/uso terapéutico , Presión Atrial , Estudios Prospectivos
2.
Indian J Thorac Cardiovasc Surg ; 39(4): 438-439, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37346445

RESUMEN

Lung hydatid cyst is a frequently encountered site of echinococcus infection after the liver. Rupture of endobronchial hydatid cyst may lead to hydatemesis or may spread to the normal lung or can cause anaphylactic reactions. Performing bronchoscopy in cases with bronchial hydatid is controversial. The thoracic hydatid cyst may destroy the native lung parenchyma or may cause mass effect on the surrounding structures. Ball valve obstruction of the bronchial hydatid cyst is not documented in the literature and here the authors present such a case as the recognition of the ball valve mechanism is important as it may cause tension pneumothorax. Supplementary information: The online version contains supplementary material available at 10.1007/s12055-023-01541-4.

3.
Indian J Thorac Cardiovasc Surg ; 39(4): 402-406, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37346447

RESUMEN

Mitral valve prolapse in the young is the most common cause of mitral regurgitation (MR). Constrictive pericarditis (CP) is a chronic and end-stage manifestation of the inflammatory process of the pericardium. Apart from equalization of diastolic pressure of the chambers as well as increased ventricular interdependence, the thickened pericardial sheath in end-stage pericarditis fails to accommodate the intrathoracic venous return due to restricted cardiac chamber filling. Intracardiac valvular pathologies might co-exist in CP. This report presents a case in which effusive CP was associated with MR and highlights the pivotal role of intraoperative transesophageal echocardiography (TEE) in the decision-making of such co-existent lesions.

4.
Ann Card Anaesth ; 22(1): 41-46, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30648678

RESUMEN

Background: Atrial septal defect (ASD) is a common congenital heart disease associated with volume overload of Right ventricle (RV) with variable effect on Left ventricle (LV). Two-dimensional (2D) Strain analysis is a new tool for objective analysis of myocardial function. This prospective study evaluated the systolic function of right and left ventricle by conventional 2D echo and strain echo and measured changes in cardiac hemodynamics that occurred in patients of ASD before and after correction. Patients and Methods: 2D echo and strain analysis of each patient before and at 48 hrs, 3 months and 6 months after correction was performed. Routine 2D echo parameters and global longitudinal strain of both ventricles were measured. Result: Improvement in LV ejection fraction (P = 0.0001) and myocardial performance index (MPI) (P < 0.0001) occurred at the end of 6 months, whereas decrease in RV MPI (P < 0.0001) and tricuspid annular plane systolic excursion (P < 0.0001) became statistically significant after 3 months of ASD correction. In comparison to conventional 2D echo, global longitudinal strain of RV decreased significantly only after 48 hours of ASD correction while there was no improvement in left ventricular global longitudinal strain after 6 month of correction. Conclusion: There was improvement in RV function with subtle change in LV function by strain imaging and most of these changes were completed within 6 months of ASD correction and nearly correlated with conventional 2DEchocardiography.


Asunto(s)
Defectos del Tabique Interatrial/fisiopatología , Función Ventricular Izquierda/fisiología , Adolescente , Niño , Preescolar , Femenino , Defectos del Tabique Interatrial/diagnóstico por imagen , Defectos del Tabique Interatrial/cirugía , Humanos , Lactante , Recién Nacido , Masculino , Estudios Prospectivos , Función Ventricular Derecha/fisiología
5.
J Hazard Mater ; 341: 277-289, 2018 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-28803052

RESUMEN

We report, for the first time, a detailed study at river water and hyporheic zone systems through collection and analyses of shallow sediments and selected source rocks, pore water, and river water from forty-two locations at the Chianan Plain (CP), SW Taiwan. The study was focused to understand the possible changes in the river water and sediment chemistry as a consequence of high arsenic (mean±SD=71.28±16.24µg/L, n=46) groundwater discharge to three major rivers in the plain. The study shows, except few locations, As concentration in river sediments corresponds to average As concentration in soil and upper crustal abundance and of source rock. Sequential extraction indicates that As is mostly bound to FeOOH. No enrichment of arsenic in river sediments or depletion of aqueous As and iron in pore water was observed down to the maximum sampling depth of 1.7m although manganese is enriched in sediments. Dissolved As concentrations in the river sediments are much lower compared to the hotspots in the CP aquifers. This suggests that no As attenuation processes are active or they cannot be detected in this zone. Mn precipitates at higher redox level compared to Fe and As and thus attenuates in the studied zone.

6.
Indian Heart J ; 69(3): 364-370, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28648435

RESUMEN

Pericardial cysts are rare with an incidence of about 1 in every 100,000 persons and one in 10 pericardial cysts may actually be a pericardial diverticulum. Pericardial cysts and diverticula share similar developmental origin and may appear as an incidental finding in chest roentgenogram in an asymptomatic patient. CT scan is considered as best modality for diagnosis and delineation of the surrounding anatomy. Cardiac MRI is recommended in the evaluation of the compressive effects caused by the pericardial cysts. The authors recommend echocardiography for serial follow up and image guided aspiration of the pericardial cyst in presence of compressive effects leading to cardiovascular and airway symptoms. A systematic approach is desirable for management of pericardial cysts depending on size, shape and compression effects, symptoms and easy access to serial Echocardiographic follow up. However, pericardial diverticulum may not be differentiated from cysts by the above testing, and only identified at surgery.


Asunto(s)
Diagnóstico por Imagen , Manejo de la Enfermedad , Quiste Mediastínico/diagnóstico , Quiste Mediastínico/cirugía , Algoritmos , Ecocardiografía , Humanos , Tomografía Computarizada por Rayos X
7.
J Hazard Mater ; 272: 112-20, 2014 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-24685527

RESUMEN

Twelve arsenic (As)-resistant bacteria (minimum inhibitory concentration ranging from 10 to 30mM and 150 to 320mM for As(III) and As(V), respectively) were isolated from the agricultural soil of the Chianan Plain in southwestern Taiwan using enrichment techniques. Eight isolates capable of oxidizing As(III) (rate of oxidation from 0.029 to 0.059µMh(-1) 10(-9) cell) and exhibiting As(III)-oxidase enzyme activity belong to Pseudomonas, Acinetobacter, Klebsiella and Comamonas genera, whereas four isolates that did not show As(III)-oxidizing activity belong to Geobacillus, Bacillus, Paenibacillus, and Enterobacter genera. Assessment of the parameters of plant growth promotion revealed that Pseudomonas sp. ASR1, ASR2 and ASR3, Geobacillus sp. ASR4, Bacillus sp. ASR5, Paenibacillus sp. ASR6, Enterobacter sp. ASR10 and Comamonas sp. ASR11, and ASR12 possessed some or all of the studied plant growth-promoting traits, including phosphate-solubilization, siderophore, IAA-like molecules and ACC deaminase production. In addition, the ability of As-resistant isolates to grow over wide ranges of pH and temperatures signify their potential application for sustainable bioremediation of As in the environment.


Asunto(s)
Arsénico/química , Bacterias/aislamiento & purificación , Plantas/microbiología , Microbiología del Suelo , Contaminantes del Suelo/química , Biodegradación Ambiental , Concentración de Iones de Hidrógeno , Pruebas de Sensibilidad Microbiana , Oxígeno/química , Fosfatos/química , Filogenia , Plantas/efectos de los fármacos , Temperatura
8.
Water Res ; 47(19): 6983-91, 2013 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-24169515

RESUMEN

The role of arsenite oxidizers in natural attenuation of arsenic pollution necessitates studies on their abundance and diversity in arsenic-contaminated aquifers. In this study, most probable number-polymerase chain reaction (MPN-PCR) and denaturing gradient gel electrophoresis (DGGE) was applied to monitor depth-wise abundance and diversity of aerobic arsenite oxidizers in arsenic-enriched groundwater of Beimen, southwestern Taiwan. The results revealed that the abundance of arsenite oxidizers ranged from 0.04 to 0.22, and the lowest ratio was observed in the most arsenic-enriched and comparatively more reduced groundwater (depth 200 m) of Beimen 1. The highest ratio was observed in the less arsenic-enriched and less reduced groundwater (depth 60 m) of Beimen 2B. DGGE profiles showed a shift in diversity of arsenite oxidizers, consisting of members of the Betaproteobacteria (61%), Alphaproteobacteria (28%) and Gammaproteobacteria (11%), depending on mainly arsenic concentration and redox level in groundwater. Groundwater with the lowest arsenic and highest dissolved oxygen at Beimen 2B harbored 78% of the arsenite oxidizers communities, while groundwater with the highest arsenic and lowest dissolved oxygen at Beimen 1 and Beimen-Jinhu harbored 17 and 22% of arsenite oxidizers communities, respectively. Pseudomonas sp. was found only in groundwater containing high arsenic at Beimen 1 and Beimen-Jinhu, while arsenite oxidizers belonging to Alpha- and Betaproteobacteria were dominated in groundwater containing low arsenic.


Asunto(s)
Arsenitos/metabolismo , Agua Subterránea/microbiología , Alphaproteobacteria/genética , Alphaproteobacteria/aislamiento & purificación , Alphaproteobacteria/metabolismo , Betaproteobacteria/genética , Betaproteobacteria/aislamiento & purificación , Betaproteobacteria/metabolismo , Biodiversidad , Electroforesis en Gel de Gradiente Desnaturalizante , Enfermedades Endémicas , Agua Subterránea/análisis , Agua Subterránea/química , Datos de Secuencia Molecular , Oxidación-Reducción , Pseudomonas/genética , Pseudomonas/metabolismo , Taiwán , Contaminantes Químicos del Agua/análisis
9.
Artículo en Inglés | MEDLINE | ID: mdl-23973597

RESUMEN

Bacterial spectra were obtained in the wavenumber range of 4000-600 cm(-1) using FTIR spectroscopy. FTIR spectral patterns were analyzed and matched with 16S-rRNA signatures of bacterial strains OS1 and OS2, isolated from oil sludge. Specific spectral bands obtained from OS1 (FJ226761), reference strain Bacillus flexus (ATCC 49095), OS2 (FJ215874) and reference strain Stenotrophomonas maltophilia (ATCC 19861) respectively, suggested that OS1 and ATCC 49095 were closely related whereas OS2 was different. The bands probably represent groups of proteins and lipids of specific bacteria. Separate peaks found in B. flexus were similar to those of OS1. The S. maltophilia (ATCC 19861) and OS2 exhibited a similar peak at 3272 cm(-1). Amide bands (I, II and III) exhibited that OS1 and B. flexus were closely related, but were different from OS2. In the fingerprint region, peak at 1096 cm(-1) and 1360 cm(-1) exhibited the specific fingerprints of OS2 and reference strain S. maltophilia (ATCC 19861), respectively. The specific fingerprint signature was found at 1339 cm(-1) for OS1 and at 1382 cm(-1) for B. flexus ATCC 49095, allowing these two strains of B. flexus to be differentiated. This spectral signature originated from phospholipid and RNA components of the cell. Principle components analysis (PCA) of spectral regions exhibited with distinct sample clusters between Bacillus flexus (ATCC 49095), S. maltophilia (ATCC 19861), OS1 and OS2 in amide and fingerprint region.


Asunto(s)
Bacillus/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Stenotrophomonas maltophilia/química , Bacillus/clasificación , Bacillus/aislamiento & purificación , Proteínas Bacterianas/química , Lípidos/química , Aguas del Alcantarillado/microbiología , Stenotrophomonas maltophilia/clasificación , Stenotrophomonas maltophilia/aislamiento & purificación
10.
J Hazard Mater ; 262: 951-9, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-23498168

RESUMEN

Arsenic (As) contamination in terrestrial geothermal systems has been identified in many countries worldwide. Concentrations higher than 0.01 mg/L are detrimental to human health. We examined potential consequences for As contamination of freshwater resources based on hydrogeochemical investigations of geothermal waters in deep wells and hot springs collected from western Anatolia, Turkey. We analyzed samples for major ions and trace element concentrations. Temperature of geothermal waters in deep wells showed extreme ranges (40 and 230 °C), while, temperature of hot spring fluids was up to 90 °C. The Piper plot illustrated two dominant water types: Na-HCO3(-) type for geothermal waters in deep wells and Ca-HCO3(-) type for hot spring fluids. Arsenic concentration ranged from 0.03 to 1.5mg/L. Dominance of reduced As species, i.e., As(III), was observed in our samples. The Eh value ranged between -250 and 119 mV, which suggests diverse geochemical conditions. Some of the measured trace elements were found above the World Health Organization guidelines and Turkish national safe drinking water limits. The variation in pH (range: 6.4-9.3) and As in geothermal waters suggest mixing with groundwater. Mixing of geothermal waters is primarily responsible for contamination of freshwater resources and making them unsuitable for drinking or irrigation.


Asunto(s)
Arsénico/análisis , Monitoreo del Ambiente/métodos , Agua Dulce , Contaminantes Químicos del Agua/análisis , Arsénico/química , Carbono/química , Geografía , Agua Subterránea , Manantiales de Aguas Termales , Concentración de Iones de Hidrógeno , Temperatura , Oligoelementos/química , Turquía , Purificación del Agua/métodos , Abastecimiento de Agua
11.
Ecotoxicol Environ Saf ; 92: 252-7, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23523002

RESUMEN

Incidental soil ingestion is expected to be a significant exposure route to arsenic for children because of the potentially high arsenic contents found in certain soils. Therefore, it is prudent to get information on oral bioaccessibility of arsenic following incidental soil ingestion and its relevance in health risk assessment for future remediation strategies. Soil samples were collected from eight villages of Ambagarh Chauki block, Chhattisgarh, Central India. The soils from seven villages had total arsenic content more than the background level of 10mgkg(-1) (ranged from 16 to 417mgkg(-1)), whereas the total arsenic content of soil from Hauditola was 7mgkg(-1). Bioaccessible arsenic assessed by the simplified bioaccessibility extraction test (SBET) ranged from 5.7 to 46.3%. Arsenic bioaccessibility was significantly influenced by clay content (R(2)=0.53, p<0.05, n=8), TOC (R(2)=0.50, p<0.05, n=8), Fe content (R(2)=0.47, p<0.05, n=8) and soil pH (R(2)=0.75, p<0.01, n=8). Risk assessment of the study sites showed that hazard index of arsenic under incidental soil ingestion was below 1 in all the study sites, except Kaudikasa. However, carcinogenic risk probability for arsenic to children from the villages Meregaon, Thailitola, Joratarai and Kaudikasa was below acceptable level (<1×10(-4)), suggesting potential health risk for children from these sites could not be overlooked. With high carcinogenic risk value (3.8E-05) and HI index (>1) for arsenic in soils of Kaudikasa, attention should be paid for development of remediation measure.


Asunto(s)
Arsénico/análisis , Exposición a Riesgos Ambientales/estadística & datos numéricos , Contaminantes del Suelo/análisis , Suelo/química , Niño , Exposición a Riesgos Ambientales/análisis , Humanos , India , Medición de Riesgo
12.
J Hazard Mater ; 262: 980-8, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-22809631

RESUMEN

The present study deals with geochemical characterization of mud fluids and sediments collected from Kunshuiping (KSP), Liyushan (LYS), Wushanting (WST), Sinyangnyuhu (SYNH), Hsiaokunshui (HKS) and Yenshuikeng (YSK) mud volcanoes in southwestern Taiwan. Chemical constituents (cations, anions, trace elements, organic carbon, humic acid, and stable isotopes) in both fluids and mud were analyzed to investigate the geochemical processes and spatial variability among the mud volcanoes under consideration. Analytical results suggested that the anoxic mud volcanic fluids are highly saline, implying connate water as the probable source. The isotopic signature indicated that δ(18)O-rich fluids may be associated with silicate and carbonate mineral released through water-rock interaction, along with dehydration of clay minerals. Considerable amounts of arsenic in mud irrespective of fluid composition suggested possible release through biogeochemical processes in the subsurface environment. Sequential extraction of As from the mud indicated that As was mostly present in organic and sulphidic phases, and adsorbed on amorphous Mn oxyhydroxides. Volcanic mud and fluids are rich in organic matter (in terms of organic carbon), and the presence of humic acid in mud has implications for the binding of arsenic. Functional groups of humic acid also showed variable sources of organic matter among the mud volcanoes being examined. Because arsenate concentration in the mud fluids was found to be independent from geochemical factors, it was considered that organic matter may induce arsenic mobilization through an adsorption/desorption mechanism with humic substances under reducing conditions. Organic matter therefore plays a significant role in the mobility of arsenic in mud volcanoes.


Asunto(s)
Arsénico/química , Monitoreo del Ambiente/métodos , Sustancias Húmicas , Contaminantes Químicos del Agua/química , Adsorción , Silicatos de Aluminio , Aniones , Calibración , Arcilla , Análisis Factorial , Geografía , Sedimentos Geológicos/química , Geología/métodos , Hidróxidos/química , Compuestos Orgánicos/química , Oxidación-Reducción , Oxígeno/química , Microbiología del Suelo , Espectroscopía Infrarroja por Transformada de Fourier , Taiwán , Erupciones Volcánicas
13.
Environ Geochem Health ; 34(5): 563-74, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22580621

RESUMEN

Drinking of arsenic (As)-contaminated groundwater has adverse effects on health of millions of people worldwide. This study aimed to determine the degree of severity of As exposure from drinking water in peri-urban Moyna and Ardebok villages, West Bengal, India. Arsenic concentrations in hair, nail and urine samp les of the individuals were determined. Arsenical dermatosis, keratosis and melanosis were investigated through medical evaluation. We have evaluated the association between As exposure from drinking water, and keratosis and melanosis outcomes. The results showed that 82.7 % of the sampled tube wells contain As concentrations above 10 µg/L, while 57.7 % contain As concentrations above 50 µg/L. The hair, nail and urine As concentrations were positively correlated with As concentrations in drinking water. In our study population, we observed a strong association between As concentrations ranging 51-99 µg/L and keratosis and melanosis outcomes, although the probability decreases at higher concentration ranges perhaps due to switching away from the use of As-contaminated tube wells for drinking and cooking purposes. High As concentrations in hair, nail and urine were observed to be associated with the age of the study population. The level of As concentrations in hair, nail and urine samples of the study population indicated the degree of severity of As exposure in the study region.


Asunto(s)
Arsénico/toxicidad , Exposición a Riesgos Ambientales , Agua Subterránea/análisis , Queratosis/inducido químicamente , Melanosis/inducido químicamente , Enfermedades de la Piel/inducido químicamente , Contaminantes Químicos del Agua/toxicidad , Adolescente , Adulto , Arsénico/análisis , Arsénico/orina , Agua Potable/análisis , Monitoreo del Ambiente , Femenino , Fluorescencia , Cabello/química , Humanos , India/epidemiología , Queratosis/epidemiología , Masculino , Melanosis/epidemiología , Persona de Mediana Edad , Uñas/química , Enfermedades de la Piel/epidemiología , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/orina
15.
Artículo en Inglés | MEDLINE | ID: mdl-21879849

RESUMEN

Arsenic (As) enrichment in groundwater has become a major global environmental disaster. Groundwater samples were collected from 64 sites located in the districts of 24-Parganas (S), and Nadia in West Bengal, India (Bhagirathi sub-basin), and 51 sites located in the districts of Comilla, Noakhali, Magura, Brahman baria, Laxmipur, Munshiganj, Faridpur and Jhenaida in Bangladesh (Padma-Meghna sub-basin). Groundwater samples were also collected from two As-affected areas (Chianan and Lanyang plains) of Taiwan (n = 26). The concentrations of major solutes in groundwater of the Padma-Meghna sub-basin are more variable than the Bhagirathi sub-basin, suggesting variations in the depositional and hydrological settings. Arsenic concentrations in groundwaters of the studied areas showed large variations, with mean As concentrations of 125 µg/L (range: 0.20 to 1,301 µg/L) in Bhagirathi sub-basin, 145 µg/L (range: 0.20 to 891 µg/L) in Padma-Meghna sub-basin, 209 µg/L (range: 1.3 to 575 µg/L) in Chianan plain, and 102 µg/L (range: 2.5 to 348 µg/L) in Lanyang plain groundwater. The concentrations of Fe, and Mn are also highly variable, and are mostly above the WHO-recommended guideline values and local (Indian and Bangladeshi) drinking water standard. Piper plot shows that groundwaters of both Bhagirathi and Padma-Meghna sub-basins are of Ca-HCO(3) type. The Chianan plain groundwaters are of Na-Cl type, suggesting seawater intrusion, whereas Lanyang plain groundwaters are mostly of Na-HCO(3) type. The study shows that reductive dissolution of Fe(III)-oxyhydroxides is the dominant geochemical process releasing As from sediment to groundwater in all studied areas.


Asunto(s)
Arsénico/análisis , Agua Potable/química , Agua Subterránea/química , Contaminantes Químicos del Agua/análisis , Adsorción , Arsénico/química , Bangladesh , Agua Potable/análisis , Agua Potable/normas , Monitoreo del Ambiente/métodos , Compuestos Férricos/análisis , Compuestos Férricos/química , Agua Subterránea/análisis , India , Hierro/análisis , Hierro/química , Hierro/normas , Manganeso/análisis , Manganeso/química , Manganeso/normas , Compuestos de Manganeso/análisis , Compuestos de Manganeso/química , Oxidación-Reducción , Taiwán , Contaminantes Químicos del Agua/química
16.
Artículo en Inglés | MEDLINE | ID: mdl-21879855

RESUMEN

Arsenic (As) enrichment in groundwater has led to extensive research, particularly on the factors responsible for its release into groundwater. In the Gangetic plain, organic matter driven microbial reduction of Fe-oxyhydroxides is considered as the most plausible mechanism of As release into groundwater. However, the role of organic matter in the aqueous environment is not well known and particularly that of organometallic complex. In this study, we have characterized bulk sediment and groundwater samples, collected from Barasat, West Bengal, India, to understand the effect of organic matter in the binding and mobility of As in the subsurface environment. The results showed a moderate correlation (R(2) = 0.49, p < 0.05) between dissolved organic carbon (DOC) and As in groundwater, suggesting that DOC has a role in releasing As into groundwater. The relative fluorescent intensity (RFI) of the dissolved humic substances in groundwater showed a maximum value of 65 QSU (mean: 47 ± 8 QSU). FT-IR spectra of the extracted humic acid fractions of the sediment showed COO-, C = O, OH, and C = C (aromatic ring) functional groups, which may act as a chelating agents with the metal(loid)s. FT-IR spectra of the HA-As complex exhibited specific peaks at 1242 and 832 cm(-1) in the fingerprint region. This is similar to the extracted humic acid fractions of the Gangetic sediment, suggesting binding of As with humic substances.


Asunto(s)
Arsénico/química , Sedimentos Geológicos/química , Agua Subterránea/química , Sustancias Húmicas/análisis , Compuestos Orgánicos/química , Arsénico/análisis , Sedimentos Geológicos/análisis , Agua Subterránea/análisis , India , Metales/análisis , Metales/química , Compuestos Orgánicos/análisis , Espectrometría de Fluorescencia , Espectroscopía Infrarroja por Transformada de Fourier , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química
17.
Artículo en Inglés | MEDLINE | ID: mdl-21879853

RESUMEN

Hot springs are the important natural sources of geothermally heated groundwater from the Earth's crust. Kuan-Tzu-Ling (KTL), Chung-Lun (CL) and Bao-Lai (BL) are well-known hot springs in southern Taiwan. Fluid and mud (sediments) samples were collected from the eruption points of three hot springs for detailed biogeochemical characterization. The fluid sample displays relatively high concentrations of Na(+) and Cl(-) compared with K(+), Mg(2+), Ca(2+), NO(2) (-), and SO(4) (2-), suggesting a possible marine origin. The concentrations of Fe, Cr, Mn, Ni, V and Zn were significantly higher in the mud sediments compared with fluids, whereas high concentrations of As, Ba, Cu, Se, Sr and Rb were observed in the fluids. This suggests that electronegative elements were released during sediment-water interactions. High As concentration in the fluids was observed to be associated with low redox (Eh) conditions. The FTIR spectra of the humic acid fractions of the sediments showed the presence of possible functional groups of secondary amines, ureas, urethanesm (amide), and silicon. The sulfate-reducing deltaproteobacterium 99% similar to Desulfovibrio psychrotolerans (GU329907) were rich in the CL hot spring while mesophilic, proteolytic, thiosulfate- and sulfur-reducing bacterium that 99% similar to Clostridium sulfidigenes (GU329908) were rich in the BL hot spring.


Asunto(s)
Monitoreo del Ambiente/métodos , Sedimentos Geológicos/análisis , Sedimentos Geológicos/microbiología , Manantiales de Aguas Termales/análisis , Manantiales de Aguas Termales/microbiología , Clostridium/clasificación , Clostridium/genética , Clostridium/aislamiento & purificación , ADN Bacteriano/genética , Desulfovibrio/clasificación , Desulfovibrio/genética , Desulfovibrio/aislamiento & purificación , Agua Subterránea/análisis , Agua Subterránea/microbiología , Sustancias Húmicas/análisis , Datos de Secuencia Molecular , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Azufre/análisis , Azufre/metabolismo , Taiwán , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismo
18.
Artículo en Inglés | MEDLINE | ID: mdl-21879856

RESUMEN

Microbial reduction of arsenate [As(V)] plays an important role in arsenic (As) mobilization in aqueous environments. In this study, we investigated reduction of arsenate by different bacterial isolates such as OSBH(1) (GU329913), OSBH(2) (GU329914), OSBH(3) (GU329915), OSBH(4) (GU329916) and OSBH(5) (GU329917), isolated from the oil sludge of a sewage treatment plant operated by the China Petroleum Refinery Company in Kaohsiung, southern Taiwan. Bacterial strains of pure culture were identified by 16S rRNA analysis (≥99 % nucleotide similarity). Morphological and 16S rRNA analysis show that the isolate OSBH(1) is similar to E. coli, OSBH(2) is similar to P. stutzeri, OSBH(3) is similar to P. putida, OSBH(4) is similar to P. aeruginosa, and OSBH(5) is similar to B. Cereus. The As(V) was transformed to As(III) in the presence of isolates OSBH(2) and OSBH(5) by a detoxification process. The potential reduction rates of As(V) were higher in the presence of isolate OSBH(5) compared to the isolate OSBH(2). The microbial growth (cell/mL) of isolate OSBH(5) was significantly higher in culture medium compared to OSBH(2). The bacterial isolates such as OSBH(1), OSBH(3) and OSBH(4) were found to be incapable of transforming the As(V). It is concluded that the activity of the oil-degrading bacterial isolates described in this work contributes to the mobilization of As in the more toxic As(III) form that affects biotic life.


Asunto(s)
Arsénico/metabolismo , Bacillus cereus/genética , Biodegradación Ambiental , Escherichia coli/genética , Contaminación por Petróleo , Pseudomonas/genética , Arseniatos/química , Arseniatos/metabolismo , Arsénico/química , Bacillus cereus/aislamiento & purificación , Bacillus cereus/metabolismo , Escherichia coli/aislamiento & purificación , Escherichia coli/metabolismo , Datos de Secuencia Molecular , Oxidación-Reducción , Reacción en Cadena de la Polimerasa , Pseudomonas/aislamiento & purificación , Pseudomonas/metabolismo , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Especificidad de la Especie , Taiwán
19.
Artículo en Inglés | MEDLINE | ID: mdl-21879854

RESUMEN

Fluid and mud samples collected from Hsiaokunshui (HKS), Wushanting (WST), Yenshuikeng (YSK), Kunshuiping (KSP), Liyushan (LYS), and Sinyangnyuhu (SYNH) mud volcanoes of southwestern Taiwan were characterized for major ions, humic substances (HS) and trace elements concentrations. The relationship between the release of arsenic (As) and activities of sulfate-reducing bacteria has been assessed to understand relevant geochemical processes in the mud volcanoes. Arsenic (0.02-0.06 mg/L) and humic substances (4.13 × 10(-4) to 1.64 × 10(-3) mM) in the fluids of mud volcanoes showed a positive correlation (r = 0.99, p < 0.05) except in Liyushan mud volcano. Arsenic and iron in mud sediments formed two separate groups i) high As, but low Fe in HKS, WST, and SYNH; and ii) low As, but high Fe in the YSK, KSP, and LYS mud volcanoes. The Eh(S.H.E.) values of the mud volcano liquids were characterized by mild to strongly reducing conditions. The HKS, SYNH, and WST mud volcanoes (near the Chishan Fault) belongs to strong reducing environment (-33 to -116 mV), whereas the LYS, YSK, and KSP mud volcanoes located near the coastal plain are under mild reducing environment (-11 to 172 mV). At low Eh values mud volcanoes, saturation index (SI) values of poorly crystalline phases such as amorphous ferric hydroxide indicate understaturation, whereas saturation is reached in relatively high Eh(S.H.E.) values mud volcanoes. Arsenic contents in sediments are low, presumably due to its release to fluids (As/Fe ratio in YSK, KSP, and LYS sediment: 4.86 × 10(-4)-6.20 × 10(-4)). At low Eh(S.H.E.) values (mild to strong reducing environment), arsenic may co-precipitate with sulfides as a consequence of sulfate reduction (As/Fe ratios in WST, HKS, and SYNH sediments: 0.42-0.69).


Asunto(s)
Sedimentos Geológicos/análisis , Sedimentos Geológicos/microbiología , Agua Subterránea/análisis , Agua Subterránea/microbiología , Arsénico/análisis , Arsénico/metabolismo , ADN Bacteriano/genética , Sustancias Húmicas/análisis , Compuestos de Hierro/análisis , Compuestos de Hierro/metabolismo , Oxidación-Reducción , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Azufre/análisis , Azufre/metabolismo , Bacterias Reductoras del Azufre/clasificación , Bacterias Reductoras del Azufre/genética , Bacterias Reductoras del Azufre/aislamiento & purificación , Bacterias Reductoras del Azufre/metabolismo , Taiwán , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismo
20.
Artículo en Inglés | MEDLINE | ID: mdl-21879858

RESUMEN

The widespread incidence of chronic arsenicosis in the Bengal Delta has led to intensive research on arsenic (As) enrichment in groundwater as well as accumulation in foodstuffs, as there are potential health risks associated with exposure to As from both sources. This study deals with human As exposure through the drinking of groundwater, consumption of locally grown foodstuffs (e.g., crops and vegetables) and cooked food in Nadia district, West Bengal. Groundwater and foodstuffs were collected and analyzed with FI-HG-AAS to estimate the total As content. Urine samples collected from human subjects were analyzed to assess the As exposure. Two major crops, boro and aman rice, showed a considerable amount of As, with mean values of 194 and 156 µg kg(-1), respectively. Significant levels of As were also found in other common crops and vegetables cultivated in this area (for example, the mean As in Arum and radish was 780 and 674 µg kg(-1), respectively). Total intake of As from foodstuffs by adults (560 µg day(-1)) and children (393 µg day(-1)) in the area was found to be at alarming levels. Arsenic exposure was demonstrated by the presence of As in urine (ranging between 154 and 276 µg L(-1)), with overall As retention of 50-60 %. The results of this study further indicate the potential risk of As exposure to local inhabitants through the food chain which is associated with continuous consumption of As-contaminated foodstuffs. Therefore, more action needs to be taken to control the contamination pathways (such as the water-soil-crop system) to protect humans from continuous ingestion of As through foodstuffs.


Asunto(s)
Arsénico/análisis , Exposición a Riesgos Ambientales/análisis , Análisis de Inyección de Flujo/métodos , Contaminación de Alimentos/análisis , Agua Subterránea/análisis , Oryza/química , Espectrofotometría Atómica/métodos , Verduras/química , Adulto , Arsénico/orina , Niño , Agua Potable/análisis , Femenino , Humanos , India , Masculino , Especificidad de la Especie
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