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1.
Dig Dis Sci ; 67(8): 4146-4153, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-34405362

RESUMEN

BACKGROUND: Percutaneous catheter drainage (PCD's) are prone to blockage because of necrosum. To improve the efficacy of PCD, necrolytic agents have been used. The present study compared the use of Streptokinase with H2O2 in saline irrigation. MATERIALS AND METHODS: This is a single-center randomized pilot study (from July 2018 to Dec 2019). Patients with infected pancreatic necrosis not showing response to PCD and saline irrigation were included in the study. Patients received either Streptokinase (Streptokinase group 50,000 IU in 100 ml normal saline) or 3% H2O2 (3% H2O2 in 100 ml normal saline in 1:10 dilution). Primary endpoints were the need for surgery and mortality while secondary endpoints were hospital stay and complications attributable to necrolytic agents. RESULTS: There were 30 patients in the study, 15 in each arm. Organ failure was seen in 23 (76.6%), single organ failure was present in 11 (47%), and multi-organ failure in 12 (53%). Bleeding complications (20% in H2O2 vs 6.6% in Streptokinase), need for surgery (73% in H2O2 vs 33.3% in Streptokinase) and mortality (60% in H2O2 vs 33% in Streptokinase) were higher in H2O2 group but the difference was not significant statistically. Post-irrigation hospital stay was lesser in the Streptokinase group compared to H2O2 group but the difference did not reach statistical significance (14.1 ± 7.7 vs 19.2 ± 11.7, p = 0.09) CONCLUSIONS: Streptokinase irrigation led to a trend for reduced need for necrosectomy and mortality. H2O2 group had more bleeding complications. Post-irrigation hospital stay was lesser in Streptokinase group.


Asunto(s)
Drenaje , Peróxido de Hidrógeno , Pancreatitis Aguda Necrotizante , Humanos , Peróxido de Hidrógeno/uso terapéutico , Pancreatitis Aguda Necrotizante/complicaciones , Pancreatitis Aguda Necrotizante/tratamiento farmacológico , Proyectos Piloto , Estudios Retrospectivos , Solución Salina , Estreptoquinasa/efectos adversos , Estreptoquinasa/uso terapéutico , Resultado del Tratamiento
2.
Analyst ; 140(5): 1466-76, 2015 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-25612313

RESUMEN

Hydrogels have become increasingly popular as immobilization materials for cells, enzymes and proteins for biosensing applications. Enzymatic biosensors that utilize hydrogel as an encapsulant have shown improvements over other immobilization techniques such as cross linking and covalent bonding. However, to date there are no studies which directly compare multiple hydrogel-graphene nanocomposites using the same enzyme and test conditions. This study compares the performance of four different hydrogels used as protein encapsulants in a mediator-free biosensor based on graphene-nanometal-enzyme composites. Alcohol oxidase (AOx) was encapsulated in chitosan poly-N-isopropylacrylamide (PNIPAAM), silk fibroin or cellulose nanocrystals (CNC) hydrogels, and then spin coated onto a nanoplatinum-graphene modified electrode. The transduction mechanism for the biosensor was based on AOx-catalyzed oxidation of methanol to produce hydrogen peroxide. To isolate the effect(s) of stimulus response on biosensor behavior, all experiments were conducted at 25 °C and pH 7.10. Electroactive surface area (ESA), electrochemical impedance spectroscopy (EIS), sensitivity to methanol, response time, limit of detection, and shelf life were measured for each bionanocomposite. Chitosan and PNIPAAM had the highest sensitivity (0.46 ± 0.2 and 0.3 ± 0.1 µA mM(-1), respectively) and electroactive surface area (0.2 ± 0.06 and 0.2 ± 0.02 cm(2), respectively), as well as the fastest response time (4.3 ± 0.8 and 4.8 ± 1.1 s, respectively). Silk and CNC demonstrated lower sensitivity (0.09 ± 0.02 and 0.15 ± 0.03 µA mM(-1), respectively), lower electroactive surface area (0.12 ± 0.02 and 0.09 ± 0.03 cm(2), respectively), and longer response time (8.9 ± 2.1 and 6.3 ± 0.8 s, respectively). The high porosity of chitosan, PNIPAAM, and silk gels led to excellent transport, which was significantly better than CNC bionanocomposites. Electrochemical performance of CNC bionanocomposites were relatively poor, which may be linked to poor gel stability. The differences between the Chitosan/PNIPAAM group and the Silk/CNC group were statistically significant (p < 0.05) based on ANOVA. Each of these composites was within the range of other published devices in the literature, while some attributes were significantly improved (namely response time and shelf life). The main advantages of these hydrogel composites over other devices is that only one enzyme is required, all materials are non-toxic, the sensor does not require mediators/cofactors, and the shelf life and response time are significantly improved over other devices.


Asunto(s)
Técnicas Biosensibles/métodos , Electrodos , Grafito/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Nanocompuestos/química , Nanopartículas/química , Resinas Acrílicas/química , Oxidorreductasas de Alcohol/química , Oxidorreductasas de Alcohol/metabolismo , Quitosano/química , Espectroscopía Dieléctrica , Electroquímica , Enzimas Inmovilizadas/química , Oro/química , Peróxido de Hidrógeno/química , Límite de Detección , Platino (Metal)/química
3.
Lupus ; 23(3): 319-22, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24407425

RESUMEN

Systemic lupus erythematosus (SLE) associated with antiphospholipid syndrome can have ocular complications. We report a 44-year-old Chinese lady with recurrent relapses of SLE and antiphospholipid syndrome with high disease activity, presenting with visual distortion in her right eye for 2 months. There was subretinal hemorrhage in her right eye, confirmed on investigations to be choroidal neovascularization secondary to a variant of age-related macular degeneration known as polypoidal choroidal vasculopathy (PCV). Anti-vascular endothelial growth factor therapy resolved her eye condition. SLE could be associated with PCV via common mechanisms, including complement pathway activation and vasculitis involving the choroidal circulation.


Asunto(s)
Neovascularización Coroidal/etiología , Lupus Eritematoso Sistémico/complicaciones , Degeneración Macular/complicaciones , Vasculitis/etiología , Adulto , Inhibidores de la Angiogénesis/uso terapéutico , Anticuerpos Antifosfolípidos/sangre , Síndrome Antifosfolípido/complicaciones , Síndrome Antifosfolípido/inmunología , Biomarcadores/sangre , Hemorragia de la Coroides/etiología , Neovascularización Coroidal/diagnóstico , Neovascularización Coroidal/tratamiento farmacológico , Neovascularización Coroidal/inmunología , Femenino , Angiografía con Fluoresceína , Humanos , Inmunosupresores/uso terapéutico , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/tratamiento farmacológico , Lupus Eritematoso Sistémico/inmunología , Degeneración Macular/diagnóstico , Degeneración Macular/tratamiento farmacológico , Degeneración Macular/inmunología , Fotoquimioterapia , Recurrencia , Tomografía de Coherencia Óptica , Resultado del Tratamiento , Vasculitis/diagnóstico , Vasculitis/tratamiento farmacológico , Vasculitis/inmunología
4.
Osteoarthritis Cartilage ; 18(1): 97-105, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19747586

RESUMEN

OBJECTIVE: Osteoarthritis is a disease process of cellular degradation of articular cartilage caused by mechanical loads and inflammatory cytokines. We studied the cellular response in native cartilage subjected to a mechanical load administered simultaneously with an inflammatory cytokine interleukin-1 (IL-1), hypothesizing that the combination of load and cytokine would result in accelerated extracellular matrix (ECM) degradation. METHODS: Mature bovine articular cartilage was loaded for 3 days (stimulation) with 0.2 and 0.5 MPa stresses, with and without IL-1 (IL-1alpha, 10 ng/ml), followed by 3 days of no stimulation (recovery). Aggrecan and collagen loss were measured as well as aggrecan cleavage using monoclonal antibodies AF-28 and BC-3 for cleavage by aggrecanases (ADAMTS) and matrix metalloproteinases (MMPs), respectively. RESULTS: Incubation with IL-1 caused aggrecan cleavage by aggrecanases and MMPs during the 3 days of stimulation. A load of 0.5 MPa inhibited the IL-1-induced aggrecan loss while no inhibition was found for the 0.2 MPa stress. There was no collagen loss during the treatments but upon load and IL-1 removal proteoglycan and collagen loss increased. Load itself under these conditions was found to have no effect when compared to the unloaded controls. CONCLUSIONS: A mechanical load of sufficient magnitude can inhibit ECM degradation by chondrocytes when stimulated by IL-1. The molecular mechanisms involved in this process are not clear but probably involve altered mechanochemical signal transduction between the ECM and chondrocyte.


Asunto(s)
Agrecanos/metabolismo , Cartílago Articular/fisiología , Colágeno/metabolismo , Interleucina-1/farmacología , Animales , Anticuerpos Monoclonales/inmunología , Cartílago Articular/efectos de los fármacos , Cartílago Articular/enzimología , Bovinos , Endopeptidasas/inmunología , Endopeptidasas/metabolismo , Metaloproteinasas de la Matriz/inmunología , Metaloproteinasas de la Matriz/metabolismo , Estrés Mecánico
7.
Int J Tuberc Lung Dis ; 24(12): 1247-1253, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33317667

RESUMEN

SETTING: Adolescents (age: 15-19 years) from the National Family Health Survey-4 (2015-2016), India.OBJECTIVE: To examine the sociodemographic and nutritional characteristics of adolescents with reported TB and those with a reported household TB exposure.METHODS: This was a cross-sectional study using secondary data. We assessed the factors associated with TB (reported in adolescents, or in a household member) using log binomial regression. We used height-for-age and body mass index for age Z-scores for stunting and thinness, respectively.RESULTS: Of the total 277 059 adolescents, 377 (136/100 000, 95%CI 123-151) were reported with TB and this was similar in both sexes. Another 4528 adolescents (1.6%, 95%CI 1.6-1.7) reported household TB exposure. Poverty and urban residence were associated with higher prevalence of TB and household TB exposure. The proportion of stunting was 40.7% (95%CI 33.5-48.0) in adolescents with reported TB and 38.2% (95%CI 36.2-40.2) (P = 0.248) in those with household TB exposure.CONCLUSION: Prevalence of reported adolescent TB was lower than adult TB. Poverty and urban residence were risk factors for both TB and household TB exposure. Chronic undernutrition was highly prevalent among those reported to have TB and in those at risk of TB by virtue of having household TB exposure.


Asunto(s)
Desnutrición , Delgadez , Tuberculosis , Adolescente , Femenino , Humanos , Masculino , Adulto Joven , Estudios Transversales , Trastornos del Crecimiento , India/epidemiología , Desnutrición/epidemiología , Prevalencia , Delgadez/epidemiología , Tuberculosis/epidemiología
8.
SAGE Open Med ; 8: 2050312120929238, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32551112

RESUMEN

INTRODUCTION: Central venous access using peripherally inserted central catheters is frequently used for patients receiving intravenous medications in the hospital or outpatients. Although there are several benefits of peripherally inserted central catheters, such as ease of insertion, low procedure-related risk and higher patient satisfaction, there are complications associated with peripherally inserted central catheter use. Despite some studies evaluating peripherally inserted central catheter line-related complications, the factors associated with peripherally inserted central catheter-related deep venous thrombosis in critically ill medical-surgical patients are poorly described. The objective of this case-control study was to identify the risk factors associated with peripherally inserted central catheter line-related deep venous thrombosis in critically ill medical-surgical intensive care unit patients in a community hospital. METHODS: We abstracted relevant clinical data from 21 cases with symptomatic peripherally inserted central catheter-related deep venous thrombosis and 42 controls with peripherally inserted central catheters but no deep venous thrombosis. RESULTS: Of the factors evaluated, female gender, the use of triple lumen peripherally inserted central catheters, larger outer diameter, and open (vs valve) peripherally inserted central catheters were associated with venous thrombosis. In this retrospective study, we did not identify any association of peripherally inserted central catheter-related deep venous thrombosis with a prior history of deep venous thrombosis, use of alteplase, antiplatelet therapy, prophylactic or therapeutic anticoagulation, international normalized ratio, platelet count and the use of peripherally inserted central catheters for total parenteral nutrition. CONCLUSION: Our study indicates that the catheter size relative to the diameter of the vein could be an important risk factor for the development of peripherally inserted central catheter-related deep venous thrombosis. The study findings should be confirmed in a larger study designed to identify risk factors of peripherally inserted central catheter-related deep venous thrombosis. In the meantime, the peripherally inserted central catheter lines should be used judiciously in critically ill patients.

9.
J Cell Biol ; 49(2): 423-9, 1971 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-19866769

RESUMEN

A method for isolation of nuclei from Saccharomyces cervisiae in high yield is described. The DNA/protein ratio of the isolated nuclei is 10 times higher than that of whole cells. Examination of these nuclei in phase and electron microscopes has shown them to be round bodies having a double membrane, microtubules, and a dark crescent at one end. The optimum conditions for extraction and resolution of histones of these nuclei on acrylamide gels have been investigated. The nuclei have an active RNA polymerase (E.C. 2.7.7.6) and are able to synthesize RNA in vitro. They are also readily stainable with Giemsa's, Feulgen's, and acridine orange methods.

10.
Int J Tuberc Lung Dis ; 23(2): 147-150, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30621811

RESUMEN

SETTING: Dakshina Kannada District, coastal South India, under the Revised National Tuberculosis Control Programme (RNTCP). OBJECTIVE: To identify the potential and practices at primary health centres (PHCs) for the assessment of nutritional status of patients with tuberculosis (TB), the basic tools used to measure height and weight and the type of nutritional counselling provided. DESIGN: A cross-sectional study was conducted with physical verification of availability of height and weight measuring equipment. Information was collected on the method used by medical officers for assessing nutritional status in PHCs, action taken in case the patient is undernourished and any formal training in nutritional assessment and counselling. RESULTS: Of 37 PHCs assessed, weighing machines were available in all and stadiometers in 38%. Medical officers were not calculating body mass index for nutritional assessment even when height and weight were being uniformly measured. Nutritional classification was mostly based on the appearance and physique of the patient. Counselling included advice to take milk, eggs and protein powders with efforts to arrange funds from village health, sanitation and nutrition committees. CONCLUSION: There is a need to equip the PHCs and their medical officers with necessary tools and training for nutritional assessment and counselling of patients with tuberculosis.


Asunto(s)
Consejo/métodos , Evaluación Nutricional , Atención Primaria de Salud/métodos , Tuberculosis/terapia , Estatura , Peso Corporal , Estudios Transversales , Equipos y Suministros/estadística & datos numéricos , Personal de Salud/estadística & datos numéricos , Humanos , India , Atención Primaria de Salud/estadística & datos numéricos
11.
J Family Med Prim Care ; 7(6): 1300-1303, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30613515

RESUMEN

BACKGROUND: Access to health care is important for persons with disability (PwD). The Government of India has launched the "Accessible India Campaign" (AIC) as a nationwide campaign for achieving universal accessibility for PwDs. OBJECTIVE: To conduct an on-site assessment for physical accessibility of all primary health care centers (PHCs) of Dakshina Kannada (DK) district in Karnataka using the AIC checklist. MATERIALS AND METHODS: A cross-sectional facility-based assessment of all 67 PHCs under the administrative control of the District Health and Family Welfare Office of the district was done using Physical Accessibility Audit Checklist prepared by the AIC. Ethics approval was obtained from the Institutional Ethics Committee and written permission was obtained from the District Health and Family Welfare Officer. Data were analyzed for frequencies and percentages. RESULTS: The Accessible India Physical Accessibility Audit Checklist consists of more than116 numbers of items. Out of 67 PHCs, 57 (85%) PHCs had an accessible pathway and 60 (90%) PHCs had a ramp for wheelchair. Only 25 (36%) PHCs had accessible doors. No PHCs had height-adjustable examination table, disable friendly toilets and only two PHCs had accessible weighing scales. CONCLUSION: This unique on-site assessment finds that our PHCs are not well equipped for catering to PwD. To realize AIC in terms of health care access for the PwD, there is much that remains desirable at primary health care level, a point of first contact in the public health system.

12.
Int J Lab Hematol ; 40(3): 335-342, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29573337

RESUMEN

INTRODUCTION: Hereditary spherocytosis (HS) is the most common inherited hemolytic anemia with heterogeneous clinico-laboratory manifestations. We evaluated the flow-cytometric tests: eosin-5'-maleimide (EMA) and flow-cytometric osmotic fragility test (FOFT) and the conventional osmotic fragility tests (OFT) for the diagnosis of hereditary spherocytosis (HS). METHODS: One hundred two suspected HS patients underwent EMA, FOFT, incubated OFT (IOFT), and room temperature OFT (RT-OFT). In addition, 10 cases of immune hemolytic anemia (IHA) were included, and performance of the above 4 tests was evaluated. For EMA and FOFT, 5 normal controls were assessed together with the patients and cutoffs were calculated using receiver-operator-characteristics curve (ROC) analysis. RESULTS: The best cutoff for %EMA decrease was 12.5%, and for FOFT, %residual red cells (%RRC) was 25.6%. The sensitivity and specificity of RT-OFT was 62.06% and 86.3%, respectively, while that of IOFT was 79.31% and 87.67%, respectively. Both flow cytometric tests performed better. Sensitivity and specificity of EMA was 86.2% and 93.9% respectively, and that of FOFT was 96.6% and 98.63%, respectively. The combination of the FOFT with IOFT or EMA dye-binding test yields a sensitivity of 100%, but with EMA, it had a higher specificity. Hb/MCHC was a predictor of the severity of the disease while %EMA decrease and %RRC did not correlate with severity of the disease. CONCLUSION: Flow-cytometric osmotic fragility test is the best possible single test followed by EMA for diagnosis of HS. A combination of FOFT and EMA can correctly diagnose 100% patients. These tests are likely to replace conventional OFTs in future.


Asunto(s)
Eosina Amarillenta-(YS)/análogos & derivados , Citometría de Flujo/métodos , Fragilidad Osmótica , Esferocitosis Hereditaria/diagnóstico , Adulto , Anciano , Eosina Amarillenta-(YS)/metabolismo , Eritrocitos , Humanos , Persona de Mediana Edad , Sensibilidad y Especificidad
13.
Theriogenology ; 68(4): 682-6, 2007 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-17573105

RESUMEN

Sperm morphometry, in combination with other objective traits, can be useful for developing a fertility index. The objective of the present study was to measure various biometric end points of frozen-thawed sperm from eight breeds of Indian buffaloes (Murrah, Surti, Tarai, Mehsana, Jaffrabadi, Bhadawari, Pandharpuri and Nili-Ravi). The sperm head of Pandharpuri buffaloes had the greatest length (10.21 microm), width (6.05 microm), area (52.31 microm(2)) and perimeter (31.86 microm). The ratio of sperm width to length was also greatest (0.61) in Pandharpuri as well as in two other breeds, viz. Nili-Ravi and Jaffrabadi. Murrah had the smallest sperm head width (4.75 microm), area (41.65 microm(2)) and perimeter (29.17 microm), but its sperm tail was longest (57.02 microm), along with that of Jaffrabadi buffaloes (56.96 microm). Based on mean values of sperm tail length, mid piece length and its width the eight buffalo breeds were categorized into three, four and five groups, respectively. Multivariate analysis and clustering put six breeds (Surti, Tarai, Mehsana, Jaffrabadi, Bhadawari and Nili-Ravi) in one cluster, whereas Murrah and Pandharpuri appeared as separate entities.


Asunto(s)
Búfalos/anatomía & histología , Espermatozoides/ultraestructura , Animales , Biometría/métodos , Búfalos/clasificación , Análisis por Conglomerados , Masculino , Microscopía de Contraste de Fase , Análisis de Componente Principal
15.
Int J Oral Maxillofac Surg ; 35(8): 746-9, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16777381

RESUMEN

Expression of the oncofoetal glycoprotein, carcinoembryonic antigen (CEA), has been observed in a number of malignancies and is also being pursued as a target for anti-cancer therapy. This study explored the status of this biochemical entity in the oral squamous cell carcinoma (SCC) in South India caused by extensive chewing habits. Squamous cell carcinoma in the study belonged to grade I and grade II. Tumour staging of the patients recruited in the study ranged from T2N1M0 to T4N3M0. Of the grade II cases studied, 88% (7 out of 8) showed expression of CEA. The 2 cases of grade I SCC of buccal mucosa also showed positive anti-CEA staining. If the results from this pilot study can be validated with a larger sample size, a role can be attributed to this tumour marker in oral neoplasia, thereby opening up avenues for using CEA as an additional diagnostic marker in oral SCC in this population and as a possible target for anti-cancer therapy.


Asunto(s)
Antígeno Carcinoembrionario/análisis , Carcinoma de Células Escamosas/química , Neoplasias de la Boca/química , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/etiología , Femenino , Humanos , India , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/etiología , Proyectos Piloto , Tabaco sin Humo/efectos adversos
16.
Cancer Res ; 41(9 Pt 1): 3461-4, 1981 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6790166

RESUMEN

Twenty min after i.p. administration of 3'-[14C]methyl-N,N-dimethyl-4-aminoazobenzene in corn oil to rats, 0.73% of administered radioactivity was present in the liver. Only 0.45% of radioactivity present in liver was recovered in the nuclear fraction, whereas 25% was present in the cytosol fraction. Twenty-seven % of cytosolic radioactivity was trichloroacetic acid precipitable, and 2% was immunoprecipitable with monospecific anti-rat liver ligandin immunoglobulin G. After 3 hr of administration, 3.2% of administered radioactivity was present in the liver, 40% of which was in the cytosol. Although 59% of radioactivity present in liver cytosol was trichloroacetic acid precipitable as compared to 27% at 20 min, the radioactivity precipitated by anti-ligandin immunoglobulin G was still 2%. When liver cytosol obtained from rats after 20 min of 3'-[14C]methyl-N,N-dimethyl-4-aminoazobenzene administration was fractionated on a Sephadex G-75 column, three peaks of radioactivity were observed. When cytosol was subjected to sodium dodecyl sulfate gel electrophoresis and fluorography, radioactivity was mainly associated with 5 proteins with molecular weights of 88,000, 47,000, 41,000, 31,000, and 22,000. When the immunoprecipitate obtained from cytosol with anti-ligandin immunoglobulin G was subjected to sodium dodecyl sulfate gel electrophoresis and fluorography, radioactivity was exclusively associated with the subunit of ligandin with a molecular weight of 22,000. Approximately 90% of the radioactivity in the immunoprecipitate was covalently associated with this subunit. These studies reveal that 3'-methyl-N,N-dimethyl-4-aminoazobenzene or its metabolites are selectively bound to the subunit of ligandin with a molecular weight of 22,000 and four other cytosol proteins in vivo.


Asunto(s)
Glutatión Transferasa/metabolismo , Hígado/metabolismo , Metildimetilaminoazobenceno/metabolismo , Proteínas/metabolismo , p-Dimetilaminoazobenceno/análogos & derivados , Animales , Citosol/análisis , Citosol/metabolismo , Electroforesis en Gel de Poliacrilamida , Inyecciones Intraperitoneales , Hígado/enzimología , Neoplasias Hepáticas/inducido químicamente , Masculino , Metildimetilaminoazobenceno/administración & dosificación , Unión Proteica , Ratas , Factores de Tiempo
17.
Cancer Res ; 43(10): 4816-21, 1983 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6411333

RESUMEN

Two radiolabeled hepatocarcinogens, N,N-dimethyl-4-aminoazobenzene (DAB) and 3'-methyl-N,N-dimethyl-4-aminoazobenzene (3'-Me-DAB), were rapidly cleared from the blood of rats after i.v. administration, with half-lives of 40 and 70 sec, respectively. Rates of hepatic uptake and biliary secretion of [14C]-3'-Me-DAB were double that of [14C]DAB within 30 min of administration. Two hr after azo dye injection, the hepatic output into bile of [14C]-3'-Me-DAB-derived radioactivity was three times that of [14C]DAB. Fifty and 75% of the total 3'-Me-DAB-derived radioactivity was recovered in blood, liver, and bile 30 and 120 min after injection while only 30 to 40% of the administered [14C]DAB-derived radioactivity was recovered at these times. We postulate the existence of an extrahepatic azo dye accumulation site which may compete with the ability of the liver to clear azo dye from the circulation and which releases 3'-Me-DAB-derived radioactivity more readily than that of DAB. Azo dye metabolites were isolated from liver, bile, and blood. The chromatographic pattern of liver metabolites generated in vivo by rats which received either hepatocarcinogen was obtained and compared with that of biliary metabolites. With either azo dye, some metabolites were located exclusively in the liver, some were secreted immediately into bile, while others were present in both liver and bile, indicating selectivity in biliary excretion.


Asunto(s)
Bilis/metabolismo , Hígado/metabolismo , Metildimetilaminoazobenceno/metabolismo , p-Dimetilaminoazobenceno/análogos & derivados , p-Dimetilaminoazobenceno/metabolismo , Animales , Cromatografía Líquida de Alta Presión , Semivida , Masculino , Ratas , Ratas Endogámicas , Distribución Tisular
18.
Cancer Res ; 51(19): 5315-21, 1991 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-1833050

RESUMEN

Cellular motility is a critical function in embryonic development, tissue repair, and tumor invasion. We used assays of scattering (epithelial colony dispersion), cell migration, and cell invasion to study cytokine-regulated motility in epithelial and carcinoma cell lines. Tumor necrosis factor (TNF) stimulated motility in 12 of 14 cell lines in one or more assay systems. The motility-stimulating activity of TNF did not correlate with its antiproliferative activity. In lines whose migration was stimulated by both TNF and scatter factor (SF), a fibroblast-derived cytokine which stimulates epithelial cell motility, saturating concentrations of TNF plus SF induced greater migration than either agent alone. Anti-TNF monoclonal antibody blocked TNF- but not SF-stimulated motility. While various other factors (basic fibroblast growth factor, interleukin 6, interleukin 2, colony-stimulating factor 1) had little or not motility-stimulating activity, phorbol-12-myristate-13-acetate (PMA), a tumor-promoting phorbol ester, scattered and/or stimulated migration in all cell lines studied. Combinations of saturating concentrations of TNF plus PMA or of SF plus PMA induced greater migration than did any agent alone. These findings suggest that (a) carcinoma cell motility may be mediated by multiple biochemical pathways and (b) TNF stimulates epithelial motility by a mechanism different from that of SF and PMA. In vivo, TNF might enhance invasiveness of some carcinomas or stimulate epithelial wound healing.


Asunto(s)
Neoplasias/fisiopatología , Factor de Necrosis Tumoral alfa/farmacología , Animales , Línea Celular , Movimiento Celular/efectos de los fármacos , Quimiotaxis , Citocinas/farmacología , Perros , Relación Dosis-Respuesta a Droga , Epitelio/fisiología , Factor 2 de Crecimiento de Fibroblastos/farmacología , Factor de Crecimiento de Hepatocito , Humanos , Técnicas In Vitro , Interleucina-2/farmacología , Interleucina-6/farmacología , Factor Estimulante de Colonias de Macrófagos/farmacología , Invasividad Neoplásica , Neoplasias/tratamiento farmacológico , Ratas , Acetato de Tetradecanoilforbol/farmacología , Factores de Tiempo
19.
Biosens Bioelectron ; 85: 479-487, 2016 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-27209574

RESUMEN

We demonstrate the first report of graphene paper functionalized with fractal platinum nanocauliflower for use in electrochemical biosensing of small molecules (glucose) or detection of pathogenic bacteria (Escherichia coli O157:H7). Raman spectroscopy, scanning electron microscopy and energy dispersive spectroscopy show that graphene oxide-coated nanocellulose was partially reduced by both thermal treatment, and further reduced by chemical treatment (ascorbic acid). Fractal nanoplatinum with cauliflower-like morphology was formed on the reduced graphene oxide paper using pulsed sonoelectrodeposition, producing a conductive paper with an extremely high electroactive surface area (0.29±0.13cm(2)), confirmed by cyclic voltammetry and electrochemical impedance spectroscopy. The platinum surface was functionalized with either glucose oxidase (via chitosan encapsulation) or a RNA aptamer (via covalent linking) for demonstration as a point of care biosensor. The detection limit for both glucose (0.08±0.02µM) and E. coli O157:H7 (≈4 CFUmL(-1)) were competitive with, or superior to, previously reported devices in the biosensing literature. The response time (6s for glucose and 12min for E. coli) were also similar to silicon biochip and commercial electrode sensors. The results demonstrate that the nanocellulose-graphene-nanoplatinum material is an excellent paper-based platform for development of electrochemical biosensors targeting small molecules or whole cells for use in point of care biosensing.


Asunto(s)
Técnicas Biosensibles/métodos , Infecciones por Escherichia coli/diagnóstico , Escherichia coli O157/aislamiento & purificación , Glucosa/análisis , Grafito/química , Papel , Sistemas de Atención de Punto , Aptámeros de Nucleótidos/química , Glucemia/análisis , Celulosa/química , Celulosa/ultraestructura , Espectroscopía Dieléctrica , Técnicas Electroquímicas/métodos , Infecciones por Escherichia coli/microbiología , Glucosa Oxidasa/química , Humanos , Nanoestructuras/química , Nanoestructuras/ultraestructura , Platino (Metal)/química
20.
Biochim Biophys Acta ; 740(2): 190-9, 1983 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-6860670

RESUMEN

Synthesis of both subunits (Ya and Yb) of ligandin in equal amounts was observed when poly(A)+ mRNA isolated from the post-mitochondrial fraction was translated in an in vitro wheat-germ system and the products were immunoprecipitated by monospecific antibody to ligandin and analyzed by SDS-polyacrylamide gel electrophoresis and fluorography. When the Mg2+ or K+ concentrations were increased in the in vitro wheat-germ system the ratio of synthesis of Yb/Ya subunits was 3. With a mRNA-dependent reticulocyte lysate, the synthesis of Ya subunits was 20-30% higher than Yb subunits. At a fixed K+ and Mg2+ concentration, the ratio of incorporation of [35S]methionine into Yb/Ya subunits remained 1 and 0.7 in wheat-germ and reticulocyte lysate systems, respectively, up to 60 min. When poly(A)+ mRNA was fractionated on a 5-20% sucrose gradient, ligandin mRNA was present in fractions having a peak sedimentation value of 11 S. When poly(A)+ mRNA was fractionated by gel electrophoresis, fractions enriched in mRNA for each subunit were obtained. By administration of [3H]leucine followed by determination of radioactivity in ligandin and total proteins by immunoprecipitation and trichloroacetic acid precipitation, respectively, synthesis of the Ya subunits was selectively stimulated by phenobarbital administration. When poly(A)+ mRNA from liver of rats administered phenobarbital was translated in vitro a selective increase in the mRNA content of Ya subunits was observed. When poly(A)+ RNA from testes was translated in the wheat-germ system and products analyzed, Yb subunits were the predominant subunit (greater than 90%) synthesized, reflecting the subunit composition of testicular ligandin. These results suggest that in spite of the close sequence homology between the two subunits of ligandin, there are separate mRNA's for each subunit which are independently regulated.


Asunto(s)
Glutatión Transferasa/genética , Biosíntesis de Proteínas , ARN Mensajero/metabolismo , Animales , Centrifugación por Gradiente de Densidad , Hígado/análisis , Hígado/efectos de los fármacos , Sustancias Macromoleculares , Masculino , Fenobarbital/farmacología , Biosíntesis de Proteínas/efectos de los fármacos , Ratas , Ratas Endogámicas , Espermina/farmacología , Testículo/análisis
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