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3.
Front Plant Sci ; 12: 696747, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34335663

RESUMEN

As an alternative to synthetic preservatives, the use of plant-based, environmentally sustainable preservatives for wood protection has tremendous potential. The current research analyzed the dimensional stability and longevity of Lannea coromandelica wood using weed extracts viz. Lantana camara L. and Ageratum conyzoides L., respectively. Petroleum ether (PE) and methanolic weed extracts were used to treat wood blocks (5 cm × 2.5 cm × 2.5 cm) at varying concentrations ranging from 0.25 to 2.00%. The PE extract of A. conyzoides resulted in maximum swelling (tangential plane, 6.30%) at 2.00%, volumetric swelling coefficient (13.17%) at 1.50%, and volumetric shrinkage coefficient (7.71%) at 1.00% concentration, while maximum shrinkage (tangential plane, 4.10%) in methanol (M) extract was observed. In L. camara methanolic extract (1.00%), maximum anti-shrink efficiency (37.01%) was recorded. In vitro mycelial growth of the wood-rotting fungus was completely inhibited by PE extract from both weeds. However, the methanolic extract of A. conyzoides resulted in maximal inhibition (75.93%) at a concentration of 2.00%. Also, PE extract (2.00%) of A. conyzoides reduced the fungal colonization to 50%, as compared with control. The lowest weight loss (decay test, 12 weeks) was observed at a 2.00% concentration of L. camara PE extract. The present research highlighted that both A. conyzoides and L. camara could be used as an environmentally sustainable wood preservative substitute that will encourage the utilization of L. coromandelica in wood-based industries.

4.
Phys Chem Chem Phys ; 22(27): 15448-15462, 2020 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-32602482

RESUMEN

The isolation of Am(iii) ion from Ln(iii) ions is very crucial for the safe disposal of nuclear wastes and thus, studies are being continuously pursued to accomplish this goal. In view of this, herein, a new conformationally rigid bitopic ligand, N,N,N',N'-tetra(2-ethylhexyl)piperazine-di-methylenecarboxamide (PIPDA) has been synthesized and studied for the separation of Am(iii) from Ln(iii) ions. The effect of structural rigidification on the selectivity of Am(iii) over Ln(iii) was compared with an open chain flexible compound, namely, N,N,N',N'-tetra(2-ethylhexyl)-3,6-(N'',N'''-dibutyl)diaza-octane-1,8-diamide (DADA). Two oxygen atoms of the diamide moiety seem to be responsible for controlling the metal ion extraction ability of PIPDA, whereas two nitrogen atoms of the piperazine moiety most probably dictate the separation factor between the Am(iii) and Eu(iii) ions in PIPDA. In addition, scalar relativistic density functional theory (DFT) in conjunction with Born-Haber thermodynamics was used herein to compliment the experimental selectivity. The experimentally observed preferential selectivity of PIPDA for Am(iii) ion over the Ln(iii) ion was corroborated by the computed extraction free energy, ΔGext. The covalent nature of bonding between the metal ions and the ligand was confirmed by analyzing the Mayer bond order and bond character analysis using the atom in molecule concept. Though the conformational rigidity of PIPDA gives stronger interaction than DADA, it does not offer a significant advantage over DADA in terms of the separation factor. The marginal increase in the separation factor for PIPDA over DADA might be attributed to the piperazine nitrogen and to the ligand architecture during complex formation.

5.
J Hazard Mater ; 397: 122476, 2020 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-32416382

RESUMEN

In view of the limited solvent system known for the Sr2+ extraction from acidic media, extraction and recovery of 90Sr from acidic medium using novel Octabenzyloxyoctakis[[[(N,N-diethylamino)carbonyl)]methyl]oxy]calix[8]arene (BOC8A) extractant in nitro alkane medium are presented in this paper. BOC8A and nitro alkanes have been synthesized and characterized by 1H NMR, 13C NMR, FTIR and GC-MS techniques. Solvent composition of 0.01 M BOC8A in nitro octane (NO) has been optimized for substantial amount of extraction of strontium from feed acidity of 3.5-4 M nitric acid, (D3.5-4 M HNO3 = 7.1-7.8). Poor extraction of Pu4+, Ba2+, Na+ and UO22+ and negligible extraction of Am3+, Cs+, Ru3+, Nd3+, Zr2+ and trivalent lanthanides are observed. Ion dissociation mechanism was found to be operative involving an extractable complex having Sr2+, BOC8A and HNO3 in a ratio of 1:1:2. About 99 % of Sr2+ from the loaded solvent was recovered with 0.01 M HNO3. DFT calculations were used to predict the structures of free, protonated BOC8A and its complex with Sr2+. DFT result showed reorientation in conformation of BOC8A due to protonation resulting in the Sr2+ extraction from acidic medium with significantly high interaction energy between Sr2+ and diprotonated form of BOC8A.

6.
J Microbiol Methods ; 151: 7-15, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29857016

RESUMEN

Marssonina coronaria causes apple blotch disease resulting in severe premature defoliation, and is distributed in many leading apple-growing areas in the world. Effective, reliable and high-quality RNA extraction is an indispensable procedure in any molecular biology study. No method currently exists for RNA extraction from M. coronaria that produces a high quantity of melanin-free RNA. Therefore, we evaluated eight RNA extraction methods including manual and commercial kits, to yield a sufficient quantity of high-quality and melanin-free RNA. Manual methods used here resulted in low quality and black colored RNA pellets showing the presence of melanin, despite all the modifications employed to original procedures. However, these methods when coupled with clean up resulted in melanin-free RNA. On the other hand, all commercial kits used were able to yield high-quality melanin-free RNA having variable yields. TRIzol™ Reagent + RNA Clean & Concentrator™-5 and Ambion-PureLink® RNA Mini Kit were found to be the best methods as the RNA extracted with these methods from 15 day old fungal culture grown on solid medium were free of melanin with good yield. RNA extracted by this improved methodology was applied for RT-PCR, subsequent PCR amplification, and isolation of calmodulin gene sequences from M. coronaria and infected apple leaf pieces. These methods are more time effective than traditional methods and take only an hour to complete. To our knowledge, this is the first report on the method of isolation of high-quality RNA for cDNA synthesis as well as isolation of the calmodulin gene sequence from this fungus.


Asunto(s)
Ascomicetos/genética , Calmodulina/genética , ADN Complementario , Malus/microbiología , Biología Molecular/métodos , ARN de Hongos/aislamiento & purificación , Ascomicetos/crecimiento & desarrollo , Ascomicetos/aislamiento & purificación , ADN de Hongos/aislamiento & purificación , Pruebas Diagnósticas de Rutina/métodos , Regulación Fúngica de la Expresión Génica , India , Enfermedades de las Plantas/microbiología , Hojas de la Planta/microbiología , Reacción en Cadena de la Polimerasa/métodos , ARN Ribosómico 28S/genética
7.
Int J Immunopathol Pharmacol ; 28(2): 240-6, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25964383

RESUMEN

The current investigation was conducted to examine kininase II or angiotensin converting enzyme (ACE), plasma prekallikrein (PK), and nitric oxide (NO) concentrations in healthy Kuwaiti subjects and newly diagnosed Kuwaiti type 2 diabetic patients before and after treatment for 6 weeks with metformin hydrochloride 500 mg twice daily after meal. With the consent of volunteers, blood and urine samples were collected after an overnight fasting. Samples were collected from the diabetic patients before and after treatment for 6 weeks. Enzyme linked immunosorbent assay (ELISA) was carried out on the aliquoted samples to measure the concentration of kininase II. NO was detected via colorimetry. Plasma Kininase II or ACE levels were significantly (P <0.01) increased by 18% in untreated diabetics when compared with healthy volunteers. However, after treatment there was a significant decrease of 20% in their ACE levels. Plasma prekallikrein levels were raised significantly (P <0.01) by 28% in diabetic patients in contrast with the control subjects and the levels were significantly reduced (P <0.0001) by 44% after treatment with metformin hydrochloride. NO levels were found to be significantly decreased in plasma by 56% and in urine by 62% in untreated diabetic patients as compared with the healthy subjects. However, when the treated diabetic patients were compared with untreated diabetics, there was an increase of 50% in plasma and 37% in urine samples. The high levels of kininase II, prekallikrein, and reduced NO may be partly responsible for the induction of renal, cardiac, and hypertensive complications associated with type 2 diabetes. Reduced NO level is an indication of endothelial dysfunction resulting in increased blood pressure. Oral anti-diabetic treatment is associated with protective effects through the reduction of kininase II (ACE), prekallikrein, and elevation of NO levels.


Asunto(s)
Diabetes Mellitus Tipo 2/metabolismo , Óxido Nítrico/metabolismo , Peptidil-Dipeptidasa A/metabolismo , Precalicreína/metabolismo , Adulto , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Estudios de Casos y Controles , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Femenino , Humanos , Hipertensión/etiología , Hipertensión/metabolismo , Kuwait , Masculino , Persona de Mediana Edad
10.
Int J Immunopathol Pharmacol ; 26(3): 699-705, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24067466

RESUMEN

Diabetes is the most common risk factor in inducing hypertension, nephropathy and retinopathy. The bradykinin (BK)-forming system has been proposed to protect cardiovascular and renal functions. We therefore evaluated urinary active and proactive kallikrein, total kininogen, plasma tissue kallikrein, plasma creatinine, plasma glucose and plasma HbA1c in newly diagnosed untreated type 2 diabetic patients and healthy subjects. In diabetic patients, urinary and plasma tissue kallikrein concentrations were significantly increased. In addition, plasma prekallikrein levels were also significantly higher. However, urinary kininogen values were significantly reduced in diabetic patients when compared with healthy subjects. This is the first investigation among Kuwaiti Arab patients with type 2 diabetes showing abnormal activities in the BK-forming system. High levels of plasma prekallikrein may be a risk factor for developing high blood pressure as well as nephropathy. The urinary and plasma tissue kallikrein concentrations were higher in diabetic patients, which could indicate the hyperactivities of these components, and may result in increased levels of plasma glucose to induce diabetes. Furthermore, the urinary kininogen levels were reduced in diabetic patients. These alterations might reflect the utilization of urinary kininogen to form BK, a potent inflammatory agent. However, this hypothesis needs further investigation.


Asunto(s)
Bradiquinina/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Adulto , Biomarcadores/sangre , Biomarcadores/orina , Glucemia/metabolismo , Estudios de Casos y Controles , Creatinina/sangre , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/orina , Progresión de la Enfermedad , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Calicreínas/orina , Quininógenos/orina , Kuwait , Masculino , Calicreínas de Tejido/sangre
11.
Ceylon Med J ; 57(2): 84-5, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22772787

RESUMEN

OBJECTIVES: Clefts of lip (CL), palate (CP), or both (CLP) are the most common orofacial congenital malformations found among live births, accounting for a large number of head and neck anomalies. To date, little is known regarding the epidemiology and pattern of orofacial clefts in Nepal. The objectives were to know the frequency and pattern of orofacial clefts in Eastern Nepal and compare with different parts of the world. METHODS: A retrospective study was conducted at B P Koirala Institute of Health Sciences to identify all children with orofacial clefts who were treated during a period of five years. Cleft lip and/or palate records were obtained from patient files in the Hospital's Medical Record Department. Age at presentation, sex, region of origin, type and laterality of the cleft were recorded. RESULTS: A total of 398 orofacial cleft cases were seen during the period. Isolated cleft lip (CL) was the most common cleft type followed closely by cleft palate (CP). CONCLUSIONS: The distribution of clefts by side showed a significant preponderance of the left side followed by the right and bilateral sides.


Asunto(s)
Labio Leporino/epidemiología , Fisura del Paladar/epidemiología , Femenino , Humanos , Masculino , Nepal/epidemiología , Estudios Retrospectivos
12.
J Hazard Mater ; 229-230: 66-71, 2012 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-22704775

RESUMEN

A novel carrier, N,N,N',N'-tetra-(2-ethylhexyl) thiodiglycolamide, T(2EH)TDGA has been studied for transport of Pd(II) from nitric acid medium across a supported liquid membrane (SLM). Pd(II) was found to be almost quantitatively transported (≈ 99.9%) within 2h from 3.0M HNO(3) medium using 0.05 M T(2EH)TDGA in n-dodecane as carrier and 0.01 M thiourea in 0.2M HNO(3) as strippant. Pd(II) transport was also studied against various parameters like feed acidity, carrier concentration, membrane pore size, etc. Palladium transport was found to be diffusion controlled and the diffusion co-efficient value was found to be 3.56 × 10(-5)cm(2)/s. Selectivity of T(2EH)TDGA for palladium over other fission products was found to be quite high, with the separation factors for Pd, with respect to different fission products being >10(3). With respect to leaching out of carrier from the membrane support, the membrane was found to be stable for six consecutive cycles. Thus, T(2EH)TDGA can be used as an efficient carrier of Pd(II) from nitric acid medium.


Asunto(s)
Glicolatos/química , Paladio/química , Reciclaje/métodos , Compuestos de Sulfhidrilo/química , Alcanos/química , Ácido Nítrico/química
13.
Talanta ; 85(2): 1217-20, 2011 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-21726762

RESUMEN

A precise, sensitive and selective method for the spectrophotometric determination of palladium (II) using N,N,N',N'-tetra(2-ethylhexyl) thiodiglycolamide T(2EH)TDGA as an extractant is described. Palladium (II) forms yellow colored complex with T(2EH)TDGA which exhibits an absorption maximum at ∼ 300 nm. The colored complex obeys Beer's law in the concentration range 1.0-15.0 µg ml(-1) of palladium with a molar absorptivity of 1.29 × 10(5)M(-1)cm(-1). The effects of various experimental parameters have been studied to establish the optimum conditions for the extraction and determination of palladium. The precision of the method has been evaluated and the relative standard deviation has been found to be less than 0.5%. The method has been successfully applied to the determination of palladium in simulated high level liquid waste (SHLW) solution.


Asunto(s)
Fraccionamiento Químico/métodos , Glicolatos/química , Paladio/análisis , Paladio/aislamiento & purificación , Espectrofotometría/métodos , Sulfuros/química , Absorción , Paladio/química , Eliminación de Residuos Líquidos
14.
Int J Immunopathol Pharmacol ; 24(2): 337-43, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21658308

RESUMEN

The present study examined the left ventricular wall thickness (LVWT), total urinary kallikrein, total plasma kininogen and mean arterial blood pressure (MABP) in diabetic and non-diabetic Wistar Kyoto (WKY) rats. The MABP was significantly raised (P<0.01) in diabetic WKY rats compared to the respective controls. The LVWT was also significantly (P<0.01) increased in diabetic WKY rats than that of control WKY rats. The mean total urinary kallikrein level and the mean total plasma kininogen level were higher (P<0.01) in diabetic WKY rats, when these rats were treated with captopril (40 mg/kg and 80 mg/kg) against the mean value obtained from control WKY rats. In conclusion, this investigation suggests that diabetes induced in these rats can cause hypertension, increased LVWT and changes in the BK-forming components. Captopril treatment caused reduction in MABP, regression of LVWT and alterations in bradykinin (BK)-forming components. The possible significance of these observations is discussed.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Presión Sanguínea/efectos de los fármacos , Bradiquinina/metabolismo , Captopril/farmacología , Complicaciones de la Diabetes/tratamiento farmacológico , Diabetes Mellitus Experimental/tratamiento farmacológico , Ventrículos Cardíacos/efectos de los fármacos , Hipertensión/tratamiento farmacológico , Hipertrofia Ventricular Izquierda/tratamiento farmacológico , Animales , Glucemia/efectos de los fármacos , Complicaciones de la Diabetes/etiología , Complicaciones de la Diabetes/metabolismo , Complicaciones de la Diabetes/fisiopatología , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatología , Ventrículos Cardíacos/patología , Hipertensión/etiología , Hipertensión/metabolismo , Hipertensión/fisiopatología , Hipertrofia Ventricular Izquierda/etiología , Hipertrofia Ventricular Izquierda/metabolismo , Hipertrofia Ventricular Izquierda/fisiopatología , Calicreínas/orina , Quininógenos/sangre , Masculino , Ratas , Ratas Endogámicas WKY , Factores de Tiempo
15.
Ultrasonics ; 51(3): 352-8, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21168892

RESUMEN

The out-of-plane vibrations of a generalized thermoelastic circular plate are studied under different environmental temperature, plate dimensions and boundary conditions. The analytical expressions for thermoelastic damping of vibration and phase velocity of circumferential surface wave modes are obtained. It is noticed that the damping of vibrations and phase velocities of circumferential surface wave modes significantly depend on thermal relaxation time in addition to thermoelastic coupling in circular plates under resonance conditions. The surface conditions also impose significant effects on the vibrations of such resonators. The expressions for displacement and temperature fields in the plate resonator are also derived and obtained. Some numerical results have also been presented for illustration purpose in case of silicon material plate.

16.
Inflammopharmacology ; 18(3): 113-7, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20195776

RESUMEN

This investigation was conducted to evaluate the tissue kallikrein activity in the synovial and paw tissues of control, non-treated adjuvant arthritic and adjuvant arthritic rats treated either with indomethacin or prednisolone. Adjuvant arthritis was induced in male Sprague-Dawley rats in the right knee by injecting 0.05 ml of a fine suspension of heat-killed Mycobacterium tubercle bacilli in liquid paraffin (5 mg/ml). Indomethacin (2.5 mg/kg given orally) and prednisolone (3.0 mg/kg given orally) treatment for 9 days caused a significant reduction (P < 0.001) in knee swelling. In non-treated adjuvant rats, synovial tissue kallikrein levels were raised (P < 0.01) than the synovial tissue kallikrein obtained from control normal rats. Prednisolone treatment resulted in reduction (P < 0.05) and indomethacin treatment produced raise (P < 0.01) in synovial tissue kallikrein levels. In non-treated arthritic rats, the paw tissue kallikrein levels were lower (P < 0.001) than the control rats; whereas, rats treated with prednisolone and indomethacine showed higher levels (P < 0.05) of paw tissue kallikrein. These results may suggest that the prednisone and indomethacin differ in their actions in inflamed synovial tissue kallikrein and have a similar effect in non-inflamed paw tissues.


Asunto(s)
Artritis Experimental/tratamiento farmacológico , Indometacina/uso terapéutico , Prednisolona/uso terapéutico , Calicreínas de Tejido/metabolismo , Animales , Artritis Experimental/metabolismo , Artritis Experimental/patología , Miembro Posterior/efectos de los fármacos , Miembro Posterior/metabolismo , Miembro Posterior/patología , Indometacina/administración & dosificación , Articulaciones/efectos de los fármacos , Articulaciones/metabolismo , Articulaciones/patología , Masculino , Mycobacterium tuberculosis/inmunología , Prednisolona/administración & dosificación , Ratas , Ratas Sprague-Dawley
17.
Inflammopharmacology ; 16(3): 151-3, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18521541

RESUMEN

The study was conducted to evaluate the total and active brain tissue kallikrein levels as well as plasma kininogen concentrations in the experimental models of epilepsy induced by maximal electroshock (MES), submaximal electroshock (SMES) and pentylenetetrazole (PTZ) in adult Sprague-Dawley rats. There was significant increase in the total brain tissue kallikrein (P < 0.001) and active tissue kallikrein (P < 0.05) after MES, SMES and PTZ induced epilepsy. Also, the total plasma kininogen levels fell significantly (P < 0.05) after production of MES, SMES and PTZ epilepsy. These results may suggest that these changes may indicate the formation of proinflammatory mediator, kinins, in the brain and peripheral circulation in experimental epilepsy.


Asunto(s)
Química Encefálica , Epilepsia/metabolismo , Calicreínas/análisis , Quininógenos/sangre , Animales , Masculino , Ratas , Ratas Sprague-Dawley
18.
Methods Find Exp Clin Pharmacol ; 29(2): 75-8, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17440623

RESUMEN

The present study examined plasma prekallikrein (PK) activity, left ventricular wall thickness (LVWT) and mean arterial blood pressure (BP) in diabetic and nondiabetic spontaneously hypertensive rats (SHR) and normotensive Wistar Kyoto (WKY) rats. The mean arterial BP was significantly raised (p < 0.01) in diabetic WKY rats and diabetic SHR when compared with their respective controls. The LVWT was significantly (p < 0.01) increased in diabetic WKY rats when compared with that in the control WKY rats. There was also an increase (p < 0.01) in the LVWT in the SHR and diabetic SHR when compared with that in the control WKY rats and diabetic WKY rats, respectively. The plasma PK activities were higher (p < 0.01) in diabetic WKY rats, SHR, and diabetic SHR against the mean value of control WKY rats. In this animal study, these findings suggest for the first time that higher plasma PK activity may serve as an indicator for predicting high BP and left ventricular hypertrophy in diabetic and hypertensive conditions. The possible significance of these observations is discussed.


Asunto(s)
Diabetes Mellitus Experimental/fisiopatología , Hipertensión/fisiopatología , Hipertrofia Ventricular Izquierda/fisiopatología , Precalicreína/metabolismo , Animales , Biomarcadores/sangre , Presión Sanguínea , Diabetes Mellitus Experimental/complicaciones , Modelos Animales de Enfermedad , Hipertensión/complicaciones , Hipertrofia Ventricular Izquierda/complicaciones , Sistema Calicreína-Quinina/fisiología , Masculino , Valor Predictivo de las Pruebas , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Estreptozocina
19.
Inflammopharmacology ; 15(6): 252-9, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18236016

RESUMEN

Nitric oxide (NO) is a signaling molecule that plays a key role in the pathogenesis of inflammation. It gives an anti-inflammatory effect under normal physiological conditions. On the other hand, NO is considered as a pro-inflammatory mediator that induces inflammation due to over production in abnormal situations. NO is synthesized and released into the endothelial cells by the help of NOSs that convert arginine into citrulline producing NO in the process. Oxygen and NADPH are necessary co-factors in such conversion. NO is believed to induce vasodilatation in cardiovascular system and furthermore, it involves in immune responses by cytokine-activated macrophages, which release NO in high concentrations. In addition, NO is a potent neurotransmitter at the neuron synapses and contributes to the regulation of apoptosis. NO is involved in the pathogenesis of inflammatory disorders of the joint, gut and lungs. Therefore, NO inhibitors represent important therapeutic advance in the management of inflammatory diseases. Selective NO biosynthesis inhibitors and synthetic arginine analogues are proved to be used for the treatment of NO-induced inflammation. Finally, the undesired effects of NO are due to its impaired production, including in short: vasoconstriction, inflammation and tissue damage.


Asunto(s)
Inflamación/fisiopatología , Óxido Nítrico/fisiología , Animales , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/uso terapéutico , Humanos , Degeneración Nerviosa/fisiopatología , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/biosíntesis , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico Sintasa/fisiología
20.
ScientificWorldJournal ; 6: 1247-61, 2006 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-17041716

RESUMEN

The kallikrein-kinin system (KKS) is a complex system produced in various organs. This system includes kininogen (precursor for kinin), kallikreins, and pharmacologically active bradykinin (BK), which is considered to be proinflammatory and/or cardioprotective. It is a proinflammatory polypeptide that is involved in many pathological conditions and can cause pain, inflammation, increased vascular permeability, vasodilation, contraction of various smooth muscles, as well as cell proliferation. On the other hand, it has been shown that BK has cardioprotective effects, as all components of KKS are located in the cardiac muscles. Numerous observations have indicated that decreased activity of this system may lead to cardiovascular diseases, such as hypertension, cardiac failure, and myocardial infarction. BK acts on two receptors, B1 and B2, which are linked physiologically through their natural stimuli and their common participation in a variety of inflammatory responses. Recently, numerous BK antagonists have been developed in order to treat several diseases that are due to excessive BK formation. Although BK has many beneficial effects, it has been recognized to have some undesirable effects that can be reversed with BK antagonists. In addition, products of this system have multiple interactions with other important metabolic pathways, such as the renin-angiotensin system.


Asunto(s)
Antagonistas de los Receptores de Bradiquinina , Bradiquinina/metabolismo , Sistema Calicreína-Quinina/efectos de los fármacos , Sistema Calicreína-Quinina/fisiología , Receptores de Bradiquinina/agonistas , Bradiquinina/biosíntesis , Enfermedades Cardiovasculares/fisiopatología , Enfermedades Cardiovasculares/prevención & control , Enfermedades Gastrointestinales/fisiopatología , Humanos , Inflamación , Cininas/efectos adversos , Cininas/fisiología , Receptores de Bradiquinina/fisiología , Sistema Renina-Angiotensina/fisiología
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