Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 32
Filtrar
1.
Appl Biochem Biotechnol ; 195(9): 5280-5298, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35606635

RESUMO

4-Chlorophenol (4-CP) is a persistent organic pollutant commonly found in petrochemical effluents. It causes toxic, carcinogenic and mutagenic effects on human beings and aquatic lives. Therefore, an environmentally benign and cost-effective approach is needed against such pollutants. In this direction, the chlorophenol degrading bacterial consortium consisting of Bacillus flexus GS1 IIT (BHU) and Bacillus cereus GS2 IIT (BHU) was isolated from a refinery site. A composite biocarrier namely polypropylene-polyurethane foam (PP-PUF) was developed for bacterial cells immobilization purpose. A lab-scale moving bed biofilm reactor (MBBR) packed with Bacillus sp. immobilized PP-PUF biocarrier was employed to analyse the effect of peptone on biodegradation of 4-CP. The statistical tool, i.e. response surface methodology (RSM), was used to optimize the process variables (4-CP concentration, peptone concentration and hydraulic retention time). The higher values of peptone concentration and hydraulic retention time were found to be favourable for maximum removal of 4-CP. At the optimized process conditions, the maximum removals of 4-CP and chemical oxygen demand (COD) were obtained to be 91.07 and 75.29%, respectively. In addition, three kinetic models, i.e. second-order, Monod and modified Stover-Kincannon models, were employed to investigate the behaviour of MBBR during 4-CP biodegradation. The high regression coefficients obtained by the second-order and modified Stover-Kincannon models showed better accuracy for estimating substrate degradation kinetics. The phytotoxicity study supported that the Vigna radiata seeds germinated in treated wastewater showed higher growth (i.e. radicle and plumule) than the untreated wastewater.


Assuntos
Clorofenóis , Águas Residuárias , Humanos , Eliminação de Resíduos Líquidos/métodos , Cinética , Biofilmes , Peptonas , Reatores Biológicos , Clorofenóis/metabolismo
2.
Chemosphere ; 257: 127145, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32497836

RESUMO

Sources of airborne particulates (PM10) were investigated in two contrasting sites over central Indo-Gangetic Plain (IGP), one representing a rural background (Mirzapur) and another as an urban pollution hotspot (Varanasi). Very high PM10 concentration was noted both in Varanasi (178 ± 105 µgm-3; N:435) and Mirzapur (131 ± 56 µgm-3; N:169) with 72% and 62% of monitoring days exceeded the national air quality standard, respectively. Particulate-bound elements contribute significant proportion of PM10 mass (15%-18%), with highest contribution from Ca (7%-10%) and Fe (2%-3%). Besides, presence of Zn (1%-3%), K (1%-2%) and Na (1%-2%) was also noted. Water-soluble ionic species contributed 15%-19% of particulate mass, primarily by the secondary inorganic aerosols (SIA). Among the SIA, sulphate (5%-7%) and nitrate (4%) were prominent, contributing 59%-62% of the total ionic load, especially in winter. Particulate-bound metallic species and ions were selectively used as signatory molecules and source apportionment of PM10 was done by multivariate factor analysis. UNMIX was able to extract particulate sources in both the locations and crustal resuspensions (dust/-soil) were identified as the dominant source contributing 57%-63% of PM10 mass. Secondary aerosols were the second important source (17%-23%), followed by emissions from biomass/-refuse burning (10-19%). Transport of airborne particulates from upper IGP by prevailing westerly were identified as the important contributor of particulates, especially during high particulate loading days. Health risks associated to particulate-bound toxic metal exposure were also assessed. Non-carcinogenic health risk was within the permissible limit while there is possibility of elevated risk for PM10-bound Cr and Cd, if adequate control measures are not in place.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Material Particulado/análise , Aerossóis/análise , Poluição do Ar/análise , Biomassa , Carvão Mineral/análise , Poeira/análise , Íons/análise , Metais/análise , Medição de Risco , Estações do Ano , Emissões de Veículos/análise
3.
Bioresour Technol ; 306: 123177, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32192956

RESUMO

The performance of a moving bed biofilm reactor (MBBR) with bio-carriers made of polypropylene-polyurethane foam (PP-PUF) was evaluated for the collective removal of phenol and ammonia. Three independent variables, including pH (5.0-8.0), retention time (2.0-12.0 h), and airflow rate (0.8-3.5 L/min) were optimized using central composite design (CCD) of response surface methodology (RSM). The maximum removal of phenol and ammonia was obtained to be 92.6, and 91.8%, respectively, in addition to the removal of 72.3% in the chemical oxygen demand (COD) level at optimum conditions. First-order and second-order kinetic models were analyzed to evaluate the pollutants removal kinetics in a MBBR. Finally, a second-order model was found to be appropriate for predicting reaction kinetics. The values of second-order rate constants were obtained to be 2.35, 0.25, and 1.85 L2/gVSS gCOD h for phenol, COD, and ammonia removal, respectively.

4.
Bioresour Technol ; 242: 92-100, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28390787

RESUMO

Benzene removal in free and immobilized cells on polyurethane foam (PUF) and polyvinyl alcohol (PVA)-alginate beads was studied using an indigenous soil bacterium Bacillus sp. M3 isolated from petroleum-contaminated soil. The important process parameters (pH, temperature and inoculums size) were optimized and found to be 7, 37°C and 6.0×108CFU/mL, respectively. Benzene removals were observed to be 70, 84 and 90% within 9days in a free cell, immobilized PVA-alginate beads and PUF, respectively under optimum operating conditions. FT-IR and GC-MS analysis confirm the presence of phenol, 1,2-benzenediol, hydroquinone and benzoate as metabolites. The important kinetic parameter ratios (µmax/Ks; L/mg·day) calculated using Monod model was found to be 0.00123 for free cell, 0.00159 for immobilized alginate beads and 0.002016 for immobilized PUF. Similarly inhibition constants (Ki; mg/L) calculated using Andrew-Haldane model was found to be 435.84 for free cell, 664.25 for immobilized alginate beads and 724.93 for immobilized PUF.


Assuntos
Bacillus , Benzeno/metabolismo , Biodegradação Ambiental , Alginatos , Reatores Biológicos , Ácido Glucurônico , Ácidos Hexurônicos , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Bioresour Technol ; 242: 45-54, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28347623

RESUMO

The biodegradation of synthetic wastewater containing Atrazine, Malathion and Parathion was studied in two stage Integrated Aerobic Treatment Plant using Bacillus sp. (consortia) isolated from agricultural field. The influent stream containing these pesticides with initial COD of 1232mg/L were fed to first reactor and treated effluent of first reactor was fed to second reactor. The maximum removal of pesticides in IATP was found to be greater than 90%. The various process parameters such as pH, DO, Redox potential and BOD5/COD were monitored during the treatment. The degradation of pesticides and its metabolites in the treated effluent were confirmed by GC-MS. Kinetic parameters such as first order rate constant (Kobs), cell yield (YX/C) and decay coefficients (Kdp) were evaluated and found to be 0.00425 per hr, 0.696mg of COD/mg MLSS and 0.0010 per hr respectively. This integrated process was found more effective than physico-chemical treatment of pesticides.


Assuntos
Reatores Biológicos , Praguicidas , Eliminação de Resíduos Líquidos , Bacillus , Biodegradação Ambiental , Purificação da Água
6.
Fitoterapia ; 81(3): 190-5, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19699784

RESUMO

The effect of detoxification on Strychnos nux-vomica seeds by traditional processing with aloe and ginger juices (B), by frying in cow ghee (C), and by boiling in cow milk (D) was investigated. The ethanolic extracts of these samples were subjected to spontaneous motor activity (SMA), pentobarbitone-induced hypnosis, PTZ induced convulsions, diazepam-assisted protection, and morphine-induced catalepsy. All samples reduced SMA and inhibited catalepsy. The seeds processed in milk (D) showed the lowest strychnine content in the cotyledons, exhibited marked inhibition of PTZ induced convulsions and maximal potentiation of hypnosis, and were the safest (LD(50)).


Assuntos
Catalepsia/tratamento farmacológico , Fármacos do Sistema Nervoso Central/uso terapêutico , Atividade Motora/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Convulsões/tratamento farmacológico , Estricnina/uso terapêutico , Strychnos nux-vomica/química , Aloe , Animais , Comportamento Animal/efeitos dos fármacos , Catalepsia/induzido quimicamente , Fármacos do Sistema Nervoso Central/efeitos adversos , Fármacos do Sistema Nervoso Central/farmacologia , Diazepam/farmacologia , Gorduras na Dieta , Feminino , Zingiber officinale , Dose Letal Mediana , Masculino , Ayurveda , Camundongos , Leite , Morfina , Pentilenotetrazol , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Ratos , Sementes , Sono/efeitos dos fármacos , Estricnina/efeitos adversos , Estricnina/farmacologia , Strychnos nux-vomica/efeitos adversos
7.
Environ Technol ; 30(4): 355-64, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19492547

RESUMO

The application of an aquatic weed, Parthenium hysterophorous, has been investigated for the removal of nickel from aqueous solutions. Parthenium hysterophorous, the weed was converted to ash and was used as an adsorbent for the removal of nickel(II) from aqueous solutions at different experimental conditions. The per cent removal of Ni increased from 67.30 to 97.54%, with the nickel(II) concentration decreasing from 477.21 to 67.83 mg L(-1) at 25 degrees C, pH 11.0. The removal was favoured at higher pH, with a maximum removal at pH 11.0. The effects of concentration and temperature are also reported. Batch adsorption kinetics are described by the Lagergren equation. The value of the rate constant of adsorption was found to be 6.82 x 10(-2) min(-1) at 67.83 mg L(-1) and 25 degrees C. The applicability of the Langmuir and Freundlich equations for the present system were tested at different temperatures, viz. 25, 50 and 75 degrees C, and the constants were calculated. Thermodynamic parameters indicate the exothermic nature of nickel(II) adsorption on P. hysterophorous ash. The adsorption capacity was found to be much better than other common adsorbents reported for the removal of nickel(II).


Assuntos
Asteraceae/química , Níquel/isolamento & purificação , Extratos Vegetais/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Concentração de Íons de Hidrogênio , Incineração , Tamanho da Partícula , Temperatura , Termodinâmica
8.
Artigo em Inglês | MEDLINE | ID: mdl-19104745

RESUMO

Sarcomatoid, or spindle cell squamous cell carcinoma (SCSC), is relatively uncommon, but may be encountered. It poses a challenge in differential diagnosis that includes other spindle cell neoplasms. We present a case where the lesion existed for 20 years and raised the potential of chronicity as a factor in inducing spindle cell morphology. Detailed immunohistochemical features are demonstrated, and discussion of the differential diagnosis is offered. The patient was an 89-year-old African-American female with an exophytic and polypoid mass of the right upper arm measuring 5.5 x 5.5 x 3.0 cm. The mass had been present for the last 20 years, and was gradually and very slowly increasing in size. After refusing surgery several times, she finally agreed to have an excision. The tumor proved to be SCSC.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Neoplasias Cutâneas/diagnóstico , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Diagnóstico Diferencial , Feminino , Humanos , Imuno-Histoquímica , Queratina-7/metabolismo , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
9.
Singapore Med J ; 49(10): e269-71, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18946595

RESUMO

Pulmonary mucormycosis is a rare, frequently fatal, fungal infection. It is usually seen in the presence of various immunocompromised states, such as diabetes mellitus, haematological malignancy or renal transplantation. In the absence of underlying predisposing conditions, presentation with infiltrates, consolidation, cavitation and mass lesion have been reported. We describe a 50-year-old man who presented with cough and chest pain for six months. Chest radiograph and computed tomography showed bilateral multiple pulmonary nodules. Surgical lung biopsy revealed angioinvasive mucormycosis. He had complete recovery with amphotericin therapy.


Assuntos
Pulmão/microbiologia , Mucormicose/diagnóstico , Anfotericina B/farmacologia , Antifúngicos/farmacologia , Biópsia , Diagnóstico Diferencial , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Mucormicose/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/microbiologia , Nódulos Pulmonares Múltiplos/patologia , Radiografia Torácica/métodos , Fumar , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
13.
Indian J Chest Dis Allied Sci ; 43(4): 231-4, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-18610668

RESUMO

A case of unusual benign tumour of the lung is described. The patient presented with a history of prolonged cough with expectoration, and fever with generalised weakness of shorter duration. Radiological examination of the chest revealed a large non-homogeneous opacity with calcification in the left lower zone. Fine needle aspiration cytology (FNAC) was inconclusive. Therefore, surgical exploration and a left lower lobectomy was performed. The diagnosis of inflammatory pseudotumour was made on histopathological examination.


Assuntos
Granuloma de Células Plasmáticas/diagnóstico , Pneumopatias/diagnóstico , Adolescente , Biópsia por Agulha Fina , Granuloma de Células Plasmáticas/diagnóstico por imagem , Granuloma de Células Plasmáticas/patologia , Humanos , Pneumopatias/patologia , Masculino , Tomografia Computadorizada por Raios X
15.
Ann Card Anaesth ; 3(1): 28-31, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17848760

RESUMO

This prospective study compared control of heart rate and haemodynamics during coronary artery revascularization without cardiopulmonary bypass using either esmolol or diltiazem. Sixty adult patients with one or two vessel coronary artery disease, were randomly divided into 2 groups. Group A (n=30) received a 50 microg/kg/ loading dose of esmolol followed by a 100 microg/kg/hr infusion, for control of heart rate during surgical anastomosis of the coronary vessel. Group-B (n=30) received 0.15 mg/kg of diltiazem as a loading dose followed by a 5 mg/hr infusion for heart rate control, during the anastomosis. It was seen that heart rate control was better in group A, 51.4 +/- 1.3 beats/min, (p <0.01) than in group B, 69.6 +/- 3.0 beats/min (p <0.05), as compared to baseline values of 80.6 +/- 12.1 beats/min in group A and 82.4 +/- 10.6 beats/min in group B respectively. Systemic vascular resistance and pulmonary artery wedge pressure were unchanged in group A but mean pulmonary artery pressure and pulmonary vascular resistance were significantly raised. Group B patients had decreased systemic vascular resistance, mean pulmonary artery pressure and pulmonary artery wedge pressure, and reduced right ventricular stroke work index at the time of distal coronary anastomosis. We concluded that although esmolol provided dramatically slower heart rates, during surgery, the resulting elevations in mean pulmonary artery pressure and pulmonary vascular resistance would require caution if used in patients with underlying right ventricular dysfunction from ischaemia or infarction. Diltiazem by virtue of its effects on systemic vascular resistance, cardiac output, and lowering of mean arterial pressure may be a better choice in hypertensive patients.

16.
Cochlear Implants Int ; 1(2): 108-13, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18791999

RESUMO

Meningitis is responsible for a considerable proportion of profoundly deafened children. At the Scottish Cochlear Implant Centre, those attending for cochlear implant assessment with post-meningitic deafness were identified from 1989 to 1999. In those found suitable, findings at surgery were recorded. Meningitis notifications in Scotland from 1988 to 1998 were also studied. Out of 550 patients, 45 were found to have post-meningitic deafness. Of these, 32 were implanted and 12 were rejected. Of those implanted, 10 were affected by cochlear ossification. In five of these patients, a full insertion of a multichannel device was impossible and as a result, auditory rehabilitation was less satisfactory. Meningitis in Scotland appears to have been declining from 1988 to 1998.

17.
Ann Thorac Surg ; 68(2): 566-8, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10475434

RESUMO

Although paraplegia after a posterolateral thoracotomy has been described as a serious complication, the occurrence of tension pneumocephalus after excision of posterior mediastinal mass has also been reported as another life-threatening complication. We report one such case.


Assuntos
Neoplasias do Mediastino/cirurgia , Neurofibroma/cirurgia , Pneumocefalia/diagnóstico por imagem , Complicações Pós-Operatórias/diagnóstico por imagem , Toracotomia , Adulto , Humanos , Masculino , Reoperação , Tomografia Computadorizada por Raios X , Trepanação
18.
Indian J Med Res ; 110: 174-7, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10680303

RESUMO

This prospective study was done to compare the control of heart rate and haemodynamics during coronary artery revascularisation without cardiopulmonary bypass using either esmolol or diltiazem. Sixty adult patients with one or two vessel coronary artery disease, were randomly divided into 2 equal groups. Group A received a 500 micrograms/kg loading dose of esmolol followed by a 100 micrograms/kg/h infusion, for control of heart rate during surgical anastomosis of the coronary vessel. While Group B received 0.15 mg/kg diltiazem as a loading dose followed by a 5 mg/h infusion for heart rate control, during the anastomosis. It was seen that heart rate control was better in Group A, 51.4 (+/- 1.3) beats/min, than in Group B, 69.6 (+/- 3.9) beats/min but the decrease in heart rate was significant in both the groups at peak effect compared to respective predrug values. Group A patients had unchanged systemic resistance and pulmonary artery wedge pressure but mean pulmonary artery pressure and pulmonary vascular resistance were significantly raised. Group B patients had decreased systemic resistance, mean pulmonary artery pressure and pulmonary artery wedge pressure, and reduced right ventricular stroke work index. We concluded that although esmolol provided dramatically slower heart rates, during surgery, the resulting elevations in mean pulmonary artery pressure and pulmonary vascular resistance would require caution if used in patients with underlying right ventricular dysfunction from ischaemia or infarction. Diltiazem by virtue of its effects on systemic vascular resistance, cardiac output, and lowering of mean arterial pressure may be a better choice in hypertensive patients.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Diltiazem/uso terapêutico , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Revascularização Miocárdica , Propanolaminas/uso terapêutico , Adulto , Doença das Coronárias/cirurgia , Humanos , Monitorização Intraoperatória
19.
Indian J Chest Dis Allied Sci ; 40(1): 65-7, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9727285

RESUMO

A case of unusual intrapulmonary foreign body in the form of a pencil is described. The penetration occurred following an insignificant fall. The diagnosis was made on CT scan and subsequently surgical removal was undertaken successfully.


Assuntos
Corpos Estranhos/diagnóstico , Lesão Pulmonar , Infecções Respiratórias/etiologia , Ferimentos Penetrantes/etiologia , Criança , Corpos Estranhos/complicações , Humanos , Masculino , Infecções Respiratórias/diagnóstico , Tomografia Computadorizada por Raios X , Madeira , Cicatrização , Ferimentos Penetrantes/diagnóstico
20.
J Cardiovasc Surg (Torino) ; 38(5): 531-3, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9358815

RESUMO

An unusual early, childhood presentation in a case with reputured non-coronary sinus of Valsalva aneurysm with Gerbode defect and severe pulmonary hypertension is described. The reasons for early rupture are discussed and anatomically important relations of membranous septum, fibroskeleton of heart and conduction system are schematically elucidated. Associated severe tricuspid and aortic regurgitation are explained to be secondary effects following the rupture of aneurysm. A technique of surgical correction of this rare association of anomalies using single PTFE patch is illustrated, cautiously safeguarding the closely related conduction system. Regurgitant aortic and tricuspid valves were also successfully repaired. In retrospect, early repair before rupture of aneurysm and onset of severe pulmonary hypertension may be more beneficial, which would also prevent the leakage of semilunar and atrioventricular valves.


Assuntos
Aneurisma Aórtico/complicações , Ruptura Aórtica/complicações , Insuficiência da Valva Aórtica/etiologia , Defeitos dos Septos Cardíacos/complicações , Seio Aórtico , Insuficiência da Valva Tricúspide/etiologia , Aneurisma Aórtico/cirurgia , Ruptura Aórtica/cirurgia , Insuficiência da Valva Aórtica/cirurgia , Procedimentos Cirúrgicos Cardiovasculares/métodos , Pré-Escolar , Defeitos dos Septos Cardíacos/cirurgia , Humanos , Hipertensão Pulmonar/etiologia , Masculino , Insuficiência da Valva Tricúspide/cirurgia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA