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1.
Indian J Med Res ; 149(4): 548-553, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-31411180

RESUMEN

Background & objectives: Dengue virus infection is endemic in India with all the four serotypes of dengue virus in circulation. This study was aimed to determine the geographic distribution of the primary and secondary dengue cases in India. Methods: A multicentre cross-sectional study was conducted at Department of Health Research / Indian Council of Medical Research (DHR)/(ICMR) viral research and diagnostic laboratories (VRDLs) and selected ICMR institutes located in India. Only laboratory-confirmed dengue cases with date of onset of illness less than or equal to seven days were included between September and October 2017. Dengue NS1 antigen ELISA and anti-dengue IgM capture ELISA were used to diagnose dengue cases while anti-dengue IgG capture ELISA was used for identifying the secondary dengue cases. Results: Of the 1372 dengue cases, 897 (65%) were classified as primary dengue and 475 (35%) as secondary dengue cases. However, the proportion varied widely geographically, with Theni, Tamil Nadu; Tirupati, Andhra Pradesh and Udupi-Manipal, Karnataka reporting more than 65 per cent secondary dengue cases while Srinagar, Jammu and Kashmir reporting as low as 10 per cent of the same. The median age of primary dengue cases was 25 yr [interquartile range (IQR 17-35] while that of secondary dengue cases was 23 yr (IQR 13.5-34). Secondary dengue was around 50 per cent among the children belonging to the age group 6-10 yr while it ranged between 20-43 per cent among other age groups. Interpretation & conclusions: Our findings showed a wide geographical variation in the distribution of primary and secondary dengue cases in India. It would prove beneficial to include primary and secondary dengue differentiation protocol in the national dengue surveillance programme.


Asunto(s)
Anticuerpos Antivirales/sangre , Virus del Dengue/patogenicidad , Dengue/sangre , Proteínas no Estructurales Virales/sangre , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Dengue/clasificación , Dengue/epidemiología , Dengue/virología , Brotes de Enfermedades , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunoglobulina M/sangre , India/epidemiología , Lactante , Masculino , Persona de Mediana Edad , Serogrupo , Adulto Joven
2.
BMC Cancer ; 18(1): 1168, 2018 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-30477461

RESUMEN

BACKGROUND: Wnt signaling has been linked with P-glycoprotein (P-gp) overexpression and which was mainly mediated by ß-catenin nuclear translocation. Flavonoids have already been reported as modulators of the Wnt/ß-catenin pathway and hence they may serve as promising agents in the reversal of P-gp mediated cancer multi drug resistance (MDR). METHODS: In this study, we screened selected flavonoids against Wnt/ß-catenin signaling molecules. The binding interaction of flavonoids (theaflavin, quercetin, rutin, epicatechin 3 gallate and tamarixetin) with GSK 3ß was determined by molecular docking. Flavonoids on P-gp expression and the components of Wnt signaling in drug-resistant KBCHR8-5 cells were analyzed by western blotting and qRT-PCR. The MDR reversal potential of these selected flavonoids against P-gp mediated drug resistance was analyzed by cytotoxicity assay in KBCHR8-5 and MCF7/ADR cell lines. The chemosensitizing potential of flavonoids was further analyzed by observing cell cycle arrest in KBCHR8-5 cells. RESULTS: In this study, we observed that the components of Wnt/ß-catenin pathway such as Wnt and GSK 3ß were activated in multidrug resistant KBCHR8-5 cell lines. All the flavonoids selected in this study significantly decreased the expression of Wnt and GSK 3ß in KBCHR8-5 cells and subsequently modulates P-gp overexpression in this drug-resistant cell line. Further, we observed that these flavonoids considerably decreased the doxorubicin resistance in KBCHR8-5 and MCF7/ADR cell lines. The MDR reversal potential of flavonoids were found to be in the order of theaflavin > quercetin > rutin > epicatechin 3 gallate > tamarixetin. Moreover, we observed that flavonoids pretreatment significantly induced the doxorubicin-mediated arrest at the phase of G2/M. Further, the combinations of doxorubicin with flavonoids significantly modulate the expression of drug response genes in KBCHR8-5 cells. CONCLUSION: The present findings illustrate that the studied flavonoids significantly enhances doxorubicin-mediated cell death through modulating P-gp expression pattern by targeting Wnt/ß-catenin signaling in drug-resistant KBCHR8-5 cells.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Resistencia a Múltiples Medicamentos/genética , Resistencia a Antineoplásicos/genética , Flavonoides/farmacología , Expresión Génica , Vía de Señalización Wnt/efectos de los fármacos , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/química , Apoptosis/efectos de los fármacos , Apoptosis/genética , Sitios de Unión , Línea Celular Tumoral , Flavonoides/química , Glucógeno Sintasa Quinasa 3 beta/química , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Humanos , Modelos Biológicos , Conformación Molecular , Unión Proteica , Relación Estructura-Actividad
4.
Mar Pollut Bull ; 181: 113893, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35797810

RESUMEN

Gracilaria edulis is one of India's most widely cultivated seaweeds. Pilot scale cultivation of Gracilaria edulis was initiated at Andaman, India for the first time. In the present study attempt has been made to identify how different water quality parameters influence the growth. Total 11 physicochemical parameters and 9 microbiological parameters, as well as chlorophyll and zooplankton, phytoplankton parameters were studied for two different seasons to evaluate which parameters influence seaweed growth. Six (nitrate, nitrite, ammonia, silicate, chlorophyll, photosynthetic active radiation) have a positive impact on seaweed growth, while some of the bacterial species showed negative impact. Lowess 3D curve fit model showed pH range from 7.59 to 7.82, N/P ratio of 2.046, rainfall 23.85-24 mm, and Photosynthetic active radiation of 376.6 W/m2 are optimum for Gracillaria growth. This model can be applied to future mass culture.


Asunto(s)
Gracilaria , Algas Marinas , Animales , Clorofila , Océanos y Mares , Zooplancton
5.
Chemosphere ; 291(Pt 2): 132931, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34793843

RESUMEN

In this study, a facile synthesis of chemical and thermal activation of biomass tea-waste materials was explored. A tea-waste biosource carbon was explored by chemical vapor deposition (CVD) method at 700 °C. The KOH-treated carbon (AC-KH) and H3PO4-treated carbon (AC-HP) were systematically studied for morphological characteristics and showed good morphological structures and a few transparent focused layered nanosheets. The elemental analysis done by scanning electron microscopy with energy-dispersive X-ray spectroscopy confirmed the presence of activated carbon. Fourier transform infrared spectroscopy (FT-IR) showed carbon-containing functional groups. The electrochemical analysis showed cyclic voltammetry (CV) curves for electric double layer capacitance (EDLC) with 3 M KOH electrolyte. The Nyquist plot obtained using electrochemical impedance spectroscopy (EIS) showed charge transfer resistance value (Rct) of 6.08 Ω. The electrochemical galvanostatic charge-discharge (GCD) study was conducted to obtain the specific capacitance (Scp) values of AC-KH, which were found to be 131.95 F/g at 0.5 A/g and also AC-HP active material was observed 55.76 F/g at 1 A/g. The AC-KH showed superior electrochemical performance when compared to AC-HP material. Hence, AC-KH is a promising active material for high-energy supercapacitor applications.


Asunto(s)
Carbón Orgánico , , Biomasa , Hojas de la Planta , Espectroscopía Infrarroja por Transformada de Fourier
6.
Biomed Pharmacother ; 139: 111632, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34243600

RESUMEN

P-glycoprotein, encoded by ATP-binding cassette transporters B1 gene (ABCB1), renders multidrug resistance (MDR) during cancer chemotherapy. Several synthetic small molecule inhibitors affect P-glycoprotein (P-gp) transport function in MDR tumor cells. However, inhibition of P-gp transport function adversely accumulates chemotherapeutic drugs in non-target normal tissues. Moreover, most small-molecule P-gp inhibitors failed in the clinical trials due to the low therapeutic window at the maximum tolerated dose. Therefore, downregulation of ABCB1-gene expression (P-gp) in tumor tissues seems to be a novel approach rather than inhibiting its transport function for the reversal of multidrug resistance (MDR). Several plant-derived phytochemicals modulate various signal transduction pathways and inhibit translocation of transcription factors, thereby reverses P-gp mediated MDR in tumor cells. Therefore, phytochemicals may be considered an alternative to synthetic small molecule P-gp inhibitors for the reversal of MDR in cancer cells. This review discussed the role of natural phytochemicals that modulate ABCB1 expression through various signal transduction pathways in MDR cancer cells. Therefore, modulating the cell signaling pathways by phytochemicals might play crucial roles in modulating ABCB1 gene expression and the reversal of MDR.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Fitoquímicos/farmacología , Fitoquímicos/uso terapéutico , Transducción de Señal/efectos de los fármacos , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Animales , Expresión Génica/efectos de los fármacos , Humanos
7.
S Afr Fam Pract (2004) ; 63(1): e1-e9, 2021 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-33881328

RESUMEN

BACKGROUND: Diabetes has been reported as the second leading cause of death and the top leading cause of death amongst women in South Africa; it is important to evaluate any epidemiological or demographic transition related to diabetes. This study evaluated the demographically stratified prevalence of type 2 diabetes mellitus (T2DM) and existing comorbidities amongst an outpatient population in a district healthcare facility in Kwazulu-Natal (KZN). METHODS: This retrospective cross-sectional study was conducted at a district hospital, and a retrospective record review of all outpatients who reported to the hospital to be treated for T2DM between the period, August 2018-January 2019, was used. Data, such as age, sex, ethnicity and any coexisting morbidity, were collected from outpatient hospital registers and electronically captured using a record review tool. RESULTS: There were significantly more female patients (3072) compared to male patients (1050) (p 0.001) with a mean age of 59.21 years. Hypertension (77.9%) and cardiovascular problems (11.16%) were most frequent. Approximately 84% of women presented with T2DM and either one or two morbidities simultaneously. Female patients were at significantly higher risk of presenting with hypertension (odds ratio [OR] = 1.44, 95% confidence interval [CI]: 1.20;1.71), whilst their risk for cardiovascular problems was significantly lower compared to male patients (OR = 0.67, 95% CI: 0.54;0.83). CONCLUSION: The prevalence of T2DM and comorbidities differed by demographic factors, such as sex, ethnicity and age. There is a need for flexible and adaptive approaches for the prevention and management of T2DM cases in order to allocate medical resources efficiently and according to the true burden of disease because of T2DM complications.


Asunto(s)
Diabetes Mellitus Tipo 2 , Estudios Transversales , Atención a la Salud , Diabetes Mellitus Tipo 2/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Sudáfrica/epidemiología
8.
Plant Biol (Stuttg) ; 21(1): 35-44, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30098101

RESUMEN

Aluminum (Al) and proton (H+ ) ions are major acid soil stress factors deleteriously affecting plant root growth and crop yield. In our preliminary studies, cotton (Gossypium hirsutum L.) seedlings displayed very sensitive phenotypes to Al and H+ rhizotoxicities. Based on previous Arabidopsis results, we aimed to characterise the Al stress responsive Sensitive to Proton rhizotoxicity 1 (GhSTOP1) transcription system in cotton using RNAi-mediated down-regulation. With the help of seed embryo apex explants, we developed transgenic cotton plants overexpressing a GhSTOP1-RNAi cassette with NPTII selection. Kanamycin-tolerant T1 seedlings were further considered for Al and H+ stress tolerance studies. Down-regulation of the GhSTOP1 increased sensitivity to Al and proton rhizotoxicities, and root growth was significantly reduced in RNAi lines. The expression profile of GhALMT1 (Aluminum-activated Malate Transporter 1), GhMATE (Multidrug and Toxic Compound Extrusion), GhALS3 (Aluminium Sensitive 3) and key genes involved in the GABA shunt were down-regulated in the transgenic RNAi lines. Additionally, the lateral root initiation process was delayed and expression of GhNAC1, which is involved in lateral roots, was also suppressed in transgenic lines. Besides, overexpression of GhSTOP1 in Arabidopsis accelerated root growth and AtMATE and AtALMT1 expression under Al stress conditions. These analyses indicate that GhSTOP1 is essential for the expression of several genes which are necessary for acid soil tolerance mechanisms and lateral root initiation.


Asunto(s)
Adaptación Fisiológica/efectos de los fármacos , Aluminio/toxicidad , Gossypium/fisiología , Proteínas de Plantas/metabolismo , Raíces de Plantas/fisiología , Protones , Factores de Transcripción/metabolismo , Dedos de Zinc , Secuencia de Aminoácidos , Arabidopsis/genética , Secuencia de Bases , Citratos/metabolismo , Clonación Molecular , Regulación hacia Abajo/efectos de los fármacos , Regulación hacia Abajo/genética , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Genes de Plantas , Malatos/metabolismo , Fenotipo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Raíces de Plantas/efectos de los fármacos , Plantas Modificadas Genéticamente , Interferencia de ARN , ARN Mensajero/genética , ARN Mensajero/metabolismo , Suelo , Estrés Fisiológico/efectos de los fármacos , Factores de Transcripción/química
9.
Int Rev Psychiatry ; 20(5): 445-51, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19012130

RESUMEN

In Asia, like other regions, the circumstances for psychiatric care and rehabilitation impose various limitations on us. However, committed professionals have been creating innovative models of excellence, which are culturally appropriate and clinically effective. In this paper, seven innovative models of psychiatric care and rehabilitation are presented. The Nitte project in India provides a comprehensive free rural psychiatric service, while transforming the 'brain drain' problem to 'brain circulation' cooperation. Through Social Enterprises in Hong Kong recovered clients are trained and employed. Senior Peer Counselling in Singapore emphasizes the relief of emotional distress by psychological methods and the primacy of communication in the healing or therapeutic relationship. Seoul Mental Health 2020, an epoch-making project in Korea, has increased the coverage rate of community mental health centres remarkably. Yuli Psychiatric Rehabilitation Model in Taiwan helps long-term inpatients to get reintegrated into the community. In Japan, models of excellence for community-based psychiatry have been developed at local government, hospital and community/NGO levels. Chinese Psychiatry Online, an excellent website, provides public education, resource searching, self-testing and consultation services for the public along with various contents for professionals. We must disseminate information about models of excellence which provide great benefit to the people who suffer from psychiatric illness without high expenses.


Asunto(s)
Trastornos Mentales/terapia , Trastornos Psicóticos/terapia , Asia , Servicios Comunitarios de Salud Mental/organización & administración , Humanos , India , Japón , Trastornos Mentales/rehabilitación , Modelos Psicológicos , Psiquiatría/estadística & datos numéricos , Trastornos Psicóticos/rehabilitación , Rehabilitación Vocacional/estadística & datos numéricos , Servicios de Salud Rural/organización & administración
10.
Bioresour Technol ; 98(10): 1907-15, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16949817

RESUMEN

Seventeen agar samples were extracted from Gelidiella acerosa (Forsskal) Feldmann and Hamel (Rhodophyta, Gelidiales) specimens collected from nine different sites on the Indian coast-five from southeast coast and four from the west coast. The agar samples were analysed. The stability characteristics of the gels of selected agar samples were studied by rheometry under applied stress conditions, i.e. variation of the storage (G') and loss moduli (G'') were studied under varying frequency and duration (time) of the stress applied. Yield, apparent and dynamic viscosities, gelling and melting temperatures, 3,6-anhydrogalactose (3,6-AG), sulphate contents and TGA (Thermogravimetric Analysis) measurements of the products were done. It was observed that the best quality agar was produced by G. acerosa occurring in the Gulf of Mannar region in the southeast coast. The gel strengths and the viscosities of agars extracted from Gelidiella acerosa occurring in the Gulf of Mannar ranged from 500 to 700gcm(-2) and 33 to 45cP for 2001 collections and for 2002 collections the corresponding values were 450 to 845gcm(-2) and 55 to 67cP respectively. On the other hand, for the agar samples extracted from the west coast of India, the gel strength and viscosities values ranged from 225 to 400gcm(-2) and from 15 to 30cP, respectively. The agars obtained from G. acerosa collected from southeast coast have been found to be suitable for bacterial culture and molecular biology. This is the first report of superior quality of agar from the Indian agarophytes.


Asunto(s)
Agar/química , Rhodophyta/química , Agar/aislamiento & purificación , Agar/normas , Medios de Cultivo/química , Medios de Cultivo/normas , India , Océanos y Mares , Transición de Fase , Temperatura , Viscosidad
11.
Environ Technol ; 28(2): 217-24, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17396416

RESUMEN

Development of aerobic granules in the aeration tank of an activated sludge system has been studied. The introduction of activated carbon particles into the aeration tank resulted in the formation of biogranules containing activated carbon as core nuclei. The presence of activated carbon also induced the formation of self-immobilized granules, which did not have any carrier particle at their core. The presence of aerobic granules enhanced the treatment efficiency of the reactor. At an organic loading rate of 32.8 kg COD m(-3)d(-1) and 0.78 h hydraulic retention time (HRT), the reactor showed 96% COD removal efficiency. At an HRT of 0.272 h and organic loading rate of 46.7 kg COD m(-3)d(-1), the reactor outlet COD remained below 100 mg l(-1). Settling velocity studies carried out on the biogranules showed that the drag coefficient of biogranules is greater than that of the rigid particle at the same Reynolds number.


Asunto(s)
Bacterias Aerobias/química , Reactores Biológicos , Carbono/química , Eliminación de Residuos Líquidos/métodos , Aerobiosis , Bacterias Aerobias/metabolismo , Glucosa/metabolismo , Aguas del Alcantarillado
12.
Chem Phys Lipids ; 204: 25-33, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28235449

RESUMEN

Interfacial hydrolysis of oxanorbornane-based amphiphile (Triol C16) by Candida rugosa lipase was investigated using real-time polarized Fourier transform-infrared reflection absorption spectroscopy (FT-IRRAS). The kinetics of hydrolysis was studied by analyzing the ester carbonyl ν(CO) stretching vibration band across the two dimensional (2D) array of molecules at the confined interface. In particular, we demonstrate Triol C16 to form Michaelis-Menten type complex, like that of lipid-substrate analogues, where the Triol C16 head group remained accessible to the catalytic triad of the lipase. The enzyme-induced selective cleavage of the ester bond was spectroscopically monitored by the disappearance of the intense ν(CO) resonance at 1736cm-1. Consequently, the in situ spectroscopic measurements evidenced selective ester hydrolysis of Triol C16 yielding Tetrol C2OH and Palmitic acid, which remained predominantly in the undissociated form at the interface. The conformation sensitive amide I (majorly ν(CO)) and the interfacial water reorganization suggested 2D ordering of the enzyme molecules following which interfacial reactions were employed towards probing the enzyme kinetics at the air/water interface. The investigation demonstrated further the potential of IRRAS spectroscopy for real-time monitoring the hydrolytic product formation and selectivity at biomimetic interfaces.


Asunto(s)
Compuestos Bicíclicos Heterocíclicos con Puentes/metabolismo , Lipasa/metabolismo , Norbornanos/metabolismo , Tensoactivos/metabolismo , Aire , Biocatálisis , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Candida/enzimología , Hidrólisis , Lipasa/química , Estructura Molecular , Norbornanos/química , Espectroscopía Infrarroja por Transformada de Fourier , Estereoisomerismo , Tensoactivos/química , Agua/química , Agua/metabolismo
13.
Indian J Exp Biol ; 44(6): 506-13, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16784123

RESUMEN

In the present investigation, the influence of different forms of cytokinins, auxins and polyamines were tested for mass multiplication and regeneration of cotton. Initially, for the identification of effective concentration for multiple shoot induction, various concentrations of BAP, Kin and 2iP along with IAA and NAA were tested. Among tested concentrations, media fortified with MS salts; B5 vitamins; 30 g/l, glucose; 2.0 mg/l, 2iP; 2.0 mg/l, IAA and 0.7 % agar showed best response for multiplication of shoot tip explants (20 shoots per shoot tip explants). In nodal explants, maximum of 18.6 shoots were obtained in the media fortified with MS salts, B5 vitamins, 30 g/l, glucose, 2.0 mg/l, 2iP, 1.0 mg/l, NAA and 0.7 % agar. Effect of different concentrations of polyamines like spermidine and putrescine were also tested along with the above said multiplication media. Among the various treatments, 20 mg/l of putrescine showed best response and the multiple of shoots were increased to 26.5 shoots per shoot tip explants and 24.5 shoots per nodal explants. Elongation of shoots was achieved on multiple shoot induction medium. Significant number of roots were initiated in the medium supplemented with MS salts, vitamin B5 and IBA (2.0 mg/l). The frequency of root induction was increased by addition of, PVP (10 mg/l) along with root induction medium and after 2 weeks, the roots reached the maximum length of 22 cm. Further, these plantlets were hardened by using sand, soil and vermiculate in 1:1:1 ratio. The hardened plants were transferred to the environmental growth chamber for proper acclimatization. The hardened plants were then transferred to field for boll yielding and they exhibited 100% survival.


Asunto(s)
Citocininas/metabolismo , Gossypium/crecimiento & desarrollo , Gossypium/metabolismo , Poliaminas/metabolismo , Silicatos de Aluminio/metabolismo , Técnicas de Cultivo de Célula/métodos , Relación Dosis-Respuesta a Droga , Germinación , Reguladores del Crecimiento de las Plantas/metabolismo , Fenómenos Fisiológicos de las Plantas , Raíces de Plantas/efectos de los fármacos , Putrescina/farmacología , Semillas/metabolismo , Espermidina/farmacología
14.
Mol Biosyst ; 12(8): 2458-70, 2016 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-27216424

RESUMEN

P-Glycoprotein (P-gp) serves as a therapeutic target for the development of inhibitors to overcome multidrug resistance in cancer cells. Although various screening procedures have been practiced so far to develop first three generations of P-gp inhibitors, their toxicity and drug interaction profiles are still a matter of concern. To address the above important problem of developing safe and effective P-gp inhibitors, we have made systematic computational and experimental studies on the interaction of natural phytochemicals with human P-gp. Molecular docking and QSAR studies were carried out for 40 dietary phytochemicals in the drug-binding site of the transmembrane domains (TMDs) of P-gp. Dietary flavonoids exhibit better interactions with homology modeled human P-gp. Based on the computational analysis, selected flavonoids were tested for their inhibitory potential against P-gp transport function in drug resistant cell lines using calcein-AM and rhodamine 123 efflux assays. It has been found that quercetin and rutin were the highly desirable flavonoids for the inhibition of P-gp transport function and they significantly reduced resistance in cytotoxicity assays to paclitaxel in P-gp overexpressing MDR cell lines. Hence, quercetin and rutin may be considered as potential chemosensitizing agents to overcome multidrug resistance in cancer.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Antineoplásicos/farmacología , Suplementos Dietéticos , Resistencia a Antineoplásicos/genética , Flavonoides/farmacología , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/antagonistas & inhibidores , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/química , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Antineoplásicos/química , Sitios de Unión , Dominio Catalítico , Línea Celular Tumoral , Simulación por Computador , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Flavonoides/química , Humanos , Ligandos , Modelos Moleculares , Simulación del Acoplamiento Molecular , Unión Proteica , Conformación Proteica , Relación Estructura-Actividad
15.
Biochim Biophys Acta ; 686(2): 245-8, 1982 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-6896286

RESUMEN

The effect of various concentrations of calcium ion (Ca2+) on dipalmitoylphosphatidylcholine (DPPC), distearoylphosphatidylcholine (DSPC) and mixed DPPC/DSPC (1:1) liposomes was studied by differential scanning calorimetry. Ca2+ concentrations of 10 mM and above split the main transition peak of DPPC into two distinguishable components, and, at 30 mM and above, also resulted in the disappearance of a pre-transition peak. The effect of Ca2+ on DSPC liposomes was even more dramatic in that it induced a more definitive split in the main transition peak and caused the loss of the pretransition peak at only 10 mM concentration. The thermograms of the DPPC/DSPC mixed liposomes were unaltered in the presence of Ca2+, even at a concentration of 50 mM. Whether or not Ca2+ is able to alter thermograms of phosphatidylcholine liposomes appears to be dependent on the degree of molecular order of the bilayer prior to interaction with Ca2+.


Asunto(s)
Calcio , Fosfatidilcolinas , Surfactantes Pulmonares , Relación Estructura-Actividad , Termodinámica
16.
Biochim Biophys Acta ; 676(1): 118-21, 1981 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-7260108

RESUMEN

The transport of sterols incorporated into the lecithin bilayer of small unilamellar liposomes through a model membrane was studied. A two-chamber diffusion cell containing liposomes with incorporated [4-14C)cholesterol or beta-[4-14C]sitosterol in the donor chamber and liposomes with unlabeled cholesterol in the receiver chamber was used. The permeability coefficients of the sterols through silastic rubber membranes which served as a model membrane were measured. The permeability for cholesterol incorporated into liposomes in a phosphatidyl choline/cholesterol molar ratio of 1 : 1, produced by sonication for 1 h, and subsequent centrifugation at 100 000 X g for 1 h, was 1.6 . 10(-8) cm sec-1. Dilution of the liposome suspension did not change the permeability coefficient significantly. The permeability coefficient of sitosterol incorporated into liposomes was about 4-times smaller than that of cholesterol. These results suggest that the sterols were delivered to the silastic membrane by the intact liposomes and that free solute was not involved in the transport to the membrane to a significant degree. The large differences in the permeability coefficients between cholesterol and sitosterol indicate that an aqueous interfacial barrier was crossed by the sterol during the delivery to the membrane.


Asunto(s)
Colesterol , Liposomas , Elastómeros de Silicona , Sitoesteroles , Difusión , Membranas Artificiales , Permeabilidad , Fosfatidilcolinas
17.
Indian J Exp Biol ; 43(10): 921-5, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16235728

RESUMEN

Highly reproducible and simple protocol for cotton somatic embryogenesis is described here by using different concentrations of maltose, glucose, sucrose and fructose. Maltose (30 g/l) is the best carbon source for embryogenic callus induction and glucose (30 g/l) was suitable for induction, maturation of embryoids and plant regeneration. Creamy white embryogenic calli of hypocotyl explants were formed on medium containing MS basal salts, myo-inositol (100 mg/l), thiamine HCI (0.3 mg/l), picloram (0.3 mg/l), Kin (0.1 mg/l) and maltose (30 g/l). During embryo induction and maturation, accelerated growth was observed in liquid medium containing NH3NO4 (1 g/l), picloram (2.0 mg/l), 2 ip (0.2 mg/l), Kin (0.1 mg/l) and glucose (30 g/l). Before embryoid induction, large clumps of embryogenic tissue were formed. These tissues only produced viable embryoids. Completely matured somatic embryos were germinated successfully on the medium fortified with MS salts, myo-inositol (50 mg/l), thiamine HCl (0.2 mg/l), GA3 (0.2 mg/l), BA (1.0 mg/l) and glucose (30 g/l). Compared with earlier reports, 65% of somatic embryo germination was observed. The abnormal embryo formation was highly reduced by using glucose (30 g/l) compared to other carbon sources. The regenerated plantlets were fertile but smaller in height than the seed derived control plants.


Asunto(s)
Carbono/química , Gossypium/metabolismo , Regeneración , Proliferación Celular , Medios de Cultivo/farmacología , Técnicas de Cultivo , Relación Dosis-Respuesta a Droga , Fructosa/farmacología , Germinación , Glucosa/metabolismo , Glucosa/farmacología , Inositol/química , Maltosa/farmacología , Picloram/farmacología , Fenómenos Fisiológicos de las Plantas , Brotes de la Planta , Sacarosa/farmacología , Tiamina/química
18.
World J Stem Cells ; 7(8): 1118-26, 2015 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-26435771

RESUMEN

Stem cells are of global excitement for various diseases including heart diseases. It is worth to understand the mechanism or role of stem cells in the treatment of heart failure. Bone marrow derived stem cells are commonly practiced with an aim to improve the function of the heart. The majority of studies have been conducted with acute myocardial infarction and a few has been investigated with the use of stem cells for treating chronic or dilated cardiomyopathy. Heterogeneity in the treated group using stem cells has greatly emerged. Ever increasing demand for any alternative made is of at most priority for cardiomyopathy. Stem cells are of top priority with the current impact that has generated among physicians. However, meticulous selection of proper source is required since redundancy is clearly evident with the present survey. This review focuses on the methods adopted using stem cells for heart diseases and outcomes that are generated so far with an idea to determine the best therapeutic possibility in order to fulfill the present demand.

19.
Biochem Pharmacol ; 33(23): 3787-91, 1984 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-6508834

RESUMEN

The interactions of calcium and neomycin with liposomes of various anionic phospholipids plus lecithin were studied by differential scanning calorimetry. Phosphatidylinositol bisphosphate differed from other acidic phospholipids in its interactions with both calcium and neomycin. Calcium, at concentrations as low as 1 mM, induced the appearance of a second transition peak in phosphatidylinositol bisphosphate-enriched liposomes only. Neomycin acted antagonistically and precluded this phase separation. In addition, neomycin lowered the phase transition temperature of phosphatidylinositol bisphosphate-lecithin liposomes while it raised the transition temperature of all other anionic phospholipid-lecithin liposomes tested. This fluidizing effect of neomycin and the antagonism to calcium may induce critical alterations of properties of biological membranes. The study supports and extends our previous findings and conclusions that phosphatidylinositol bisphosphate may play a crucial role in the expression of aminoglycoside toxicity.


Asunto(s)
Calcio , Liposomas , Neomicina , Fosfatidilcolinas , Rastreo Diferencial de Calorimetría , Fosfatidilinositoles , Fosfatidilserinas , Relación Estructura-Actividad
20.
J Pharm Sci ; 72(12): 1465-7, 1983 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-6663487

RESUMEN

Calcium ion (Ca2+, 5 mM) caused a large upward shift in the transition temperature (Tc) of dipalmitoyl phosphatidylglycerol liposomes, apparently interacting with external and internal lipid in the bilayer. Neomycin (1 mM) caused only a small shift, apparently not penetrating the internal lipid domains. When liposomes were first incubated with Ca2+ followed by neomycin, the shift in Tc indicated displacement of Ca2+ by the drug. Liposomes of dipalmitoyl phosphatidylcholine or distearoyl phosphatidylcholine did not interact significantly with either cation. In mixed dipalmitoyl phosphatidylcholine-dipalmitoyl phosphatidylglycerol and distearoyl phosphatidylcholine-dipalmitoyl phosphatidylglycerol liposomes, addition of Ca2+ or neomycin resulted in phase separation.


Asunto(s)
Calcio , Liposomas , Neomicina , Fosfolípidos , Fenómenos Químicos , Química Física , Temperatura , Termodinámica
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