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1.
Drug Res (Stuttg) ; 72(7): 367-371, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35724675

RESUMEN

Coenzyme Q10 (CoQ10) is an efficient antioxidant produced endogenously in a living organism. It acts as an important cofactor in the electron transport system of mitochondria and reported as a safe supplement in humans and animals with minimal adverse effect. CoQ10 is found naturally, as a trans configuration, chemical nomenclature of which is 2,3- dimethoxy-5- methyl-6-decaprenyle -1,4-benzoquinone. It is found in the body in two forms. In quinone form (oxidized form), it serves as an electron transporter that transfers the electrons in the electron transport chain between various complexes, and in ubiquinol form (reduced form), it serves as potent antioxidants by scavenging free radicals or by tocopherol regeneration in the living organism. Its primary roles include synthesis of adenosine triphosphate (ATP), stabilizes lipid membrane, antioxidant activity, cell growth stimulation, and cell death inhibition. CoQ10 has shown a variety of pharmacological and clinical effects including neuroprotective, hepatoprotective, anti-atherosclerotic, anticonvulsant, antidepressant, anti-inflammatory, antinociceptive, cardiovascular, antimicrobial, immunomodulatory, and various effects on the central nervous system. Present review has set about to bring updated information regarding to clinical and preclinical activities of CoQ10, which may be helpful to researchers to explore a new bioactive molecules for various therapeutic application.


Asunto(s)
Antioxidantes , Ubiquinona , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Suplementos Dietéticos , Radicales Libres/metabolismo , Humanos , Mitocondrias , Ubiquinona/análogos & derivados , Ubiquinona/farmacología
2.
Mymensingh Med J ; 31(1): 15-23, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34999674

RESUMEN

There is progressive increase of Hb levels is observed during course of intrauterine development of fetus but high concentrations found at birth. In preterm neonate normal Hb is characteristically deviated from term neonate. Breast milk is the only natural ideal food for both term and preterm babies from birth up to 6 months. Preterm milk was found to contain significantly higher concentrations nutrients particularly iron than term milk. Preterm human milk is more suitable for the premature infant than term human milk. As Hb concentration varies in term and preterm babies in different counties in different feeding practices. The purpose of this longitudinal descriptive study is to find out the pattern of changes in the Hb level among exclusively breastfed preterm and term infants during the first six months of life. This study was carried in the Neonatal Intensive Care Unit (NICU), Mymensingh Medical College Hospital (MMCH), Mymensingh from September 2016 to February 2018. One hundred fifty (150) neonates both term and preterm were included in this study and followed up to 6 months of age. After admission informed written consent was taken from parents, thorough history taking and clinical examination were done. Data were collected in a pre-designed case record form. All the babies of Group A provided 2mg/kg iron supplementation from 6 weeks for 2 months for universal recommendation. Hb level was measured of all exclusively breast feed babies at admission after birth then next follow-up at 6 weeks, 3 months and 6 months. All information regarding history, anthropometrics measurement, Hb level was recorded in structural questionnaire. Data analysis was done by SPSS version 20.0. Male were predominant in both groups. Most of the preterm (72.0%) and term babies (65.3%) were delivered by vaginal route. Mean Hb level was found significantly higher among preterm babies than term babies after birth were 16.55g/dl and 15.98g/dl respectively. Sharp fall of Hb concentration was observed after birth up to 6 weeks in both preterm and term babies but Hb level was found significantly lower in preterm in comparison to term babies (9.27gm/dl vs. 9.58gm/dl). In term babies, even after 6 weeks fall of Hb level continued to 3 months of age followed by gradual increase up to 6 months without iron supplementation. Hb level of in preterm babies gradually increased from 6 weeks up to 6 months with universal iron supplementation. Hb level fall sharply up to 6 weeks in both exclusively breastfed term and preterm babies but even after 6 weeks term babies experienced gradual fall of Hb levels up to 3 months. Hb level increases in exclusively breast-fed term babies without iron supplementation from 3 months of age. Hb level in exclusively breastfed preterm babies increase from 6 weeks onward might be effect of universal iron supplementation.


Asunto(s)
Lactancia Materna , Recien Nacido Prematuro , Conducta Alimentaria , Femenino , Hemoglobinas/análisis , Humanos , Lactante , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Masculino
3.
Braz. j. biol ; 82: 1-8, 2022. tab
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1468421

RESUMEN

The experiment was carried out on mango cv. Dusehri to investigate the effect of N, P and K fertilizers on vegetative, reproductive growth, yield and fruit quality. Eight different fertilizer combinations such as T1 (control), T2 (N), T3 (P), T4 (K), T5 (NP), T6 (NK), T7 (PK) and T8 (NPK) were used. Individual or combine fertilizer application of N (1000 g), P (750 g) and K (750 g) were applied during growing season in February and August. All the treatments significantly influenced on vegetative growth, flowering, fruiting, yield and other physiochemical attributes of mango as compared to control. Least effect was observed with individual fertilizer application while combine fertilizer treatments enhanced most of the investigated parameters. Especially, qualitative traits showed non significant differences between treated and untreated mango trees. However, among the different treatments T8 (NPK) showed significance for fruiting aspects such as maximum size of growth flushes (177.51 mm), total number of panicles/tree (845), total number of flowers/panicle (974), sex ratio (69.18%), fruit retention (13.85%), total number of fruits/tree (379), yield (82 kg/tree), fruit weight (197.5 g), pulp weight (135.5 g) and physiochemical parameters namely TSS (24.53), Vit. C (57.63 mg/100 mL) and total sugar (20.84%). In general, combine application of NPK (T8) were the most effective in enhancing fruiting aspects, yield, physiochemical characteristics as well as improved fruit quality of mango trees.


O experimento foi realizado em manga cv. Dusehri para investigar o efeito dos fertilizantes N, P e K no crescimento vegetativo, reprodutivo, produtividade e de qualidade do fruto. Foram utilizadas oito combinações diferentes de fertilizantes: T1 (controle), T2 (N), T3 (P), T4 (K), T5 (NP), T6 (NK), T7 (PK) e T8 (NPK). Cada tratamento de N(1.000 g), P (750 g) e K (750 g) foi aplicado duas vezes durante a estação de crescimento em fevereiro e agosto. Todos os tratamentos influenciaram significativamente o crescimento vegetativo, floração, frutificação, produtividade e outros atributos físico-químicos da manga em relação ao controle. Menos efeito foi observado com a aplicação individual de fertilizante, enquanto os tratamentos combinados aumentaram a maioria dos parâmetros investigados. Especialmente as características qualitativas mostraram diferenças não significativas entre mangueiras tratadas e não tratadas. No entanto, entre os diferentes tratamentos, T8 (NPK) apresentou significância para aspectos de frutificação, como tamanho máximo de folgas de crescimento (177,51 mm), número total de panículas/árvore (845), número total de flores/panícula (974), razão sexual (69,18%), retenção de frutos (13,85%), número total de frutos/árvore (379), produção (82 kg/árvore), peso do fruto (197,5 g) e peso da polpa (135,5 g), além de parâmetros físico-químicos, como TSS (24,53), vitamina C (57,63 mg/100 mL) e açúcar total (20,84%). Em geral, a aplicação combinada de NPK (T8) foi a mais eficaz no aprimoramento dos aspectos de frutificação, produtividade, características físico-químicas, além da melhoria da qualidade dos frutos das mangueiras.


Asunto(s)
Fósforo/administración & dosificación , Mangifera/crecimiento & desarrollo , Mangifera/efectos de los fármacos , Nitrógeno/administración & dosificación , Estándar de Identidad y Calidad de Productos y Servicios , Potasio/administración & dosificación
4.
Plant Biol (Stuttg) ; 23 Suppl 1: 152-161, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33176068

RESUMEN

The interaction of mineral nutrients with metals/metalloids and signalling molecules is well known. In the present study, we investigated the effect of phosphorus (P) in mitigation of arsenic (As) stress in mustard (Brassica juncea L.). The study was conducted to investigate potential of 30 mg P·kg-1 soil P supplement (diammonium phosphate) to cope up with the adverse effects of As stress (24 mg As·kg-1 soil) in mustard plants Supplementation of P influenced nitric oxide (NO) generation, which up-regulated proline metabolism, ascorbate-glutathione system and glyoxalase system and alleviated the effects of on photosynthesis and growth. Arsenic stress generated ROS and methylglyoxal content was scavenged through P-mediated NO, and reduced As translocation from roots to leaves. The involvement of NO under P-mediated alleviation of As stress was substantiated with the use of cPTIO (NO biosynthesis inhibitor) and SNP (NO inducer). The reversal of P effects on photosynthesis under As stress with the use of cPTIO emphasized the role of P-mediated NO in mitigation of As stress and protection of photosynthesis The results suggested that P reversed As-induced oxidative stress by modulation of NO formation, which regulated antioxidant machinery. Thus, P-induced regulatory interaction between NO and reversal of As-induced oxidative stress for the protection of photosynthesis may be suggested for sustainable crops.


Asunto(s)
Arsénico , Planta de la Mostaza , Antioxidantes , Arsénico/toxicidad , Suplementos Dietéticos , Óxido Nítrico , Estrés Oxidativo , Fósforo , Fotosíntesis
5.
Br Poult Sci ; 57(4): 566-75, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27108741

RESUMEN

The present study was conducted to evaluate the role of extruded flaxseed (EFS) and α-tocopherol acetate (ATA) for the enhancement of polyunsaturated fatty acids ratio (PUFA) over saturated fatty acids (SFA) in broiler meat as a source of healthier meat. A total of 96 one-d-old Cobb 550 broilers were randomly divided into 8 treatments with three replicates having 4 birds in each. EFS (extruded at 155°C) at 100, 150 and 200 g/kg alone and in combination with ATA at 200 mg/kg were supplemented through normal feed from the third week onward. During the 6-week growth period, body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR) and mortality were recorded. At slaughter, weight of liver, heart and kidney and fat content in breast and leg meat were measured. Fatty acid profiles in breast and leg meat were developed to estimate the PUFA to SFA ratio. The results revealed that FI and FCR changed significantly in all groups and BWG increased in all the supplemented groups. The weight of liver, kidney and heart increased more in the supplemented group containing the maximum level of EFS with ATA compared with single supplementation of EFS. The fat content in breast and leg meat decreased as the inclusion level of EFS increased. The level was low in leg meat compared with breast meat. Mortality decreased in all supplemented groups. The PUFA to SFA ratio was significantly higher in leg meat (3.23) compared with breast meat (1.81) and the study therefore indicates that ATA and EFS supplementation could be used to improve the PUFA to SFA ratio in broiler meat.


Asunto(s)
Pollos/fisiología , Dieta/veterinaria , Suplementos Dietéticos , Lino/química , Carne/análisis , Valor Nutritivo , alfa-Tocoferol/metabolismo , Alimentación Animal/análisis , Animales , Pollos/crecimiento & desarrollo , Ácidos Grasos/análisis , Ácidos Grasos Insaturados/análisis , Carne/normas , Distribución Aleatoria , Semillas/química , alfa-Tocoferol/administración & dosificación
6.
J Neonatal Perinatal Med ; 6(2): 137-44, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24246516

RESUMEN

INTRODUCTION: Of annual four million neonatal deaths, majority in the developing world, approximately three-quarters die within the first week of life. Pakistan has one of the highest newborn mortality rates. STUDY DESIGN: We conducted a cross sectional study to assess knowledge, attitudes and practices of women of reproductive age in rural Pakistan. RESULTS: Of 1490 mothers interviewed, prevalence of newborn care practices ranged between 32% (early bathing of newborn) and 69% (use of traditional cord applications). Uptake of antenatal care services was identified as a strong predictor of good newborn care after controlling for skilled birth attendance, socio-economic status, age of mother and sex of infant (OR = 1.26; 95% CI: 1.00-1.57). CONCLUSIONS: The association of uptake of antenatal care services with good newborn care highlights the necessity to improve coverage of services with the integration of counseling about newborn care in order to reduce the burden of neonatal morbidity and mortality.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Atención Prenatal/métodos , Adulto , Lactancia Materna/estadística & datos numéricos , Estudios Transversales , Femenino , Humanos , Higiene , Recién Nacido , Partería/estadística & datos numéricos , Madres/psicología , Pakistán , Aceptación de la Atención de Salud/estadística & datos numéricos , Atención Prenatal/psicología , Atención Prenatal/estadística & datos numéricos , Salud Rural , Factores Socioeconómicos , Adulto Joven
7.
Bangladesh Med Res Counc Bull ; 39(1): 6-10, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23923404

RESUMEN

The study was performed to compare the blood glucose lowering effect of Swietenia mahagoni seeds with an oral antidiabetic drug, rosiglitazone in experimentally induced diabetic rats. Twentyfour healthy Long Evans Norwegian strain of rats were included in the study and divided into four groups (A, B, C and D) comprising 6 rats each. Group A (control group) received standard rat food for 14 days. Diabetes was induced by a single intraperitoneal administration of alloxan 120 mg/kg body weight in Group B, C and D. Group B was given standard food for 10 days and considered as diabetic control. Group C and D were treated with ethanolic extract of Swietenia mahagoni seeds 1000 mg/kg and rosiglitazone 10 mg/kg orally respectively. Administration of ethanolic extract of Swietenia mahagoni seeds in group C and rosiglitazone in group D produced a significant reduction in blood glucose level as compared to diabetic control (group B). Histological examination of pancreas showed destruction of beta cells in Islets of pancreas in group B whereas retaining of islets and few degranulations of beta cells of pancreas found in group C and group D. The observations and results of the present study provide information that ethanolic extract of Swietenia mahagoni seeds has hypoglycaemic effect in experimentally induced diabetic rats which requires further investigation.


Asunto(s)
Glucemia/efectos de los fármacos , Diabetes Mellitus Experimental/tratamiento farmacológico , Meliaceae , Fitoterapia , Tiazolidinedionas/uso terapéutico , Aloxano/administración & dosificación , Animales , Bangladesh , Diabetes Mellitus Experimental/inducido químicamente , Femenino , Hipoglucemiantes/uso terapéutico , Masculino , Extractos Vegetales/uso terapéutico , Ratas , Ratas Long-Evans , Rosiglitazona , Semillas
8.
J Enzyme Inhib Med Chem ; 22(3): 343-50, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17674816

RESUMEN

Six novel triorganotin(IV) 2-maleimidopropanoato complexes: R3SnOCOCH3(CH)(COCH)2, (R: Me(l), Et(2), n-Pr(3), n-Bu(4), Ph(5), Bz(6) have been synthesized. Their solid-state configuration has been determined by FT IR and lI9mSn Mössbauer spectroscopy. The tin(IV) atom is five-coordinated in all the complexes with 2-maleimidopropanoic acid behaving as a monoanionic bidentate ligand coordinating the tin(IV) atom through a chelating or bridging carboxylate group. The solution-state configuration has been elucidated by means of 1H-, 13C- and 119Sn-NMR spectroscopy which assigned a tetrahedron. Elemental analysis and FAB MS data also supported a 1:1 metal to ligand stoichiometry. The title complexes have been screened in vitro for anti-tumour, anti-fungal, anti-leishmanial and urease inhibition activities and displayed promising results.


Asunto(s)
Compuestos Orgánicos de Estaño/química , Compuestos Orgánicos de Estaño/farmacología , Animales , Antifúngicos/síntesis química , Antifúngicos/química , Antifúngicos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Evaluación Preclínica de Medicamentos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Humanos , Técnicas In Vitro , Leishmania/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Compuestos Orgánicos de Estaño/síntesis química , Espectrometría de Masa Bombardeada por Átomos Veloces , Espectroscopía Infrarroja por Transformada de Fourier , Espectroscopía de Mossbauer , Relación Estructura-Actividad , Tripanocidas/síntesis química , Tripanocidas/química , Tripanocidas/farmacología , Ureasa/antagonistas & inhibidores
9.
Mymensingh Med J ; 11(1): 49-53, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12148399

RESUMEN

Hereditary haemoglobin disorders (E-beta Thalassaemia & Thalassaemia) are inherited as recessive disorders so that the heterozygote subjects are generally healthy. They commonly present with progressive pallor, thalassaemic facies, splenohepatomegaly & growth retardation. Diagnosis of carriers & patients are usually confirmed by haemoglobin electrophoresis. Transfusion-chelation therapy is usually employed for their treatment. Allogenic bone marrow transplantation is the only definite cure. Gene therapy remains to be the major challenging goal of future curative therapy. During the last 10 years wit medical advances, the number of pregnancies in thalassaemia is increasing. Normal pregnancy can be maintained with regular packed blood cells transfusion given carefully. In Bangladesh, HHD can be prevented by I. carrier identification and marriage counseling, II. passing and enforcing laws against marriage between two carriers, III. introducing thalassaemia in school curriculum and IV. creating public awareness.


Asunto(s)
Hemoglobinopatías , Bangladesh , Hemoglobinopatías/diagnóstico , Hemoglobinopatías/prevención & control , Hemoglobinopatías/terapia , Humanos
10.
Acta Crystallogr D Biol Crystallogr ; 55(Pt 6): 1204-5, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10329786

RESUMEN

The basic lectin from Artocarpus hirsuta specific towards methyl alpha-galactose has been purified and crystallized using the hanging-drop vapour-diffusion method with ammonium sulfate as precipitant. Three different crystal forms, orthorhombic I, orthorhombic II and hexagonal, were grown under the same crystallization conditions. The orthorhombic forms belonged to space group P212121 with unit-cell dimensions a = 92.9, b = 99.8, c = 166. 2 A and a = 89.9, b = 121.9, c = 131.6 A, respectively. The unit-cell dimensions of the hexagonal form were a = b = 84.1 and c = 271.7 A and the space group was P6122.


Asunto(s)
Fabaceae/química , Lectinas/química , Plantas Medicinales , Semillas/química , Cristalización , Cristalografía por Rayos X , Fabaceae/embriología , Lectinas de Plantas , Conformación Proteica
11.
Glimpse ; 18(1): 8, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-12291504

RESUMEN

The study aims to examine the perceptions, causes, and treatment of diseases among the people of a few selected villages in Matlab and their relation to traditional culture and interventions made by BRAC and ICDDR,B in the form of rural development and MCH-FP programs. Four sets of villages were chosen purposively--two DSS and the other two non-DSS. In one of the DSS villages the MCH-FP program is underway, while the other does not have such programs. Likewise, one of the non-DSS villages has the rural development program of BRAC, while the other does not have any. From each village 10 respondents were selected purposively to gather information. The perception of disease is mostly defined in terms of the functions of the body. On very few occasions it is defined in terms of the action rendered by germs or the pathological condition of the body organs. The difference between the meaning and the actual diseases is often blurred. While identifying the causes, often the reference is made to invisible spirits, locally known as alga batash. The modes of treatment combine both modern and traditional elements. However, the health teaching educates them about the perception, causes, and treatment of certain diseases. In society, the elderly people, religious preachers, and traditional healers play important roles to influence the mind of the people. Sometimes gender relations and other structural features also bear on the minds of the illiterate poor. The difference between the intervention and non-intervention villages is expressed in the fact that the people of the intervention villages are constantly exposed to the agents making changes, while in the non-intervention villages it is intermittent. Traditional culture still plays an important role in the construction of disease perception and the choice of treatment, while modern approaches are combined with it. The intervention procedures widen modern approaches but could not eliminate the traditional notions altogether.


Asunto(s)
Cultura , Enfermedad , Educación en Salud , Planificación en Salud , Medicina Tradicional , Percepción , Población Rural , Terapéutica , Asia , Bangladesh , Conducta , Atención a la Salud , Demografía , Países en Desarrollo , Educación , Salud , Servicios de Salud , Medicina , Organización y Administración , Población , Características de la Población , Psicología
12.
J Biol Chem ; 268(22): 16378-87, 1993 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-8344923

RESUMEN

The binding of winged bean basic agglutinin (WBA I) to 4-methylumbelliferyl (MeUmb) galactosides was examined by extrinsic fluorescence titration and stopped-flow spectrofluorimetry. Upon binding to WBA I, MeUmb alpha-galactosides show quenching in fluorescence intensity, decrease in UV absorbance with a concomitant blue shift, and decrease in fluorescence excited-state lifetimes. However, their beta-analogues show enhancement in fluorescence intensity, increase in UV absorbance with a red shift, and an increase in fluorescence excited-state lifetimes. This implies that the umbelliferyl groups of alpha- and beta-galactosides experience non-polar and polar microenvironments, respectively, upon binding to WBA I. Replacement of the anomeric hydroxyl group of galactose by 4-methylumbelliferyl moiety increases the affinity of resulting saccharides. Substitution of C-2 hydroxyl of galactose by an acetamido group leads to increased affinity due to a favorable entropy change. This suggests that acetamido group of MeUmb-alpha/beta-GalNAc binds to a relatively non-polar subsite of WBA I. Most interestingly, this substitution also reduces the association rate constants dramatically. Inspection of the activation parameters reveals that the enthalpy of activation is the limiting factor for the differences in the forward rate constants for these saccharides and the entropic contribution to the activation energy is small.


Asunto(s)
Colorantes Fluorescentes/metabolismo , Galactósidos/metabolismo , Himecromona/análogos & derivados , Lectinas/metabolismo , Acetilgalactosamina/metabolismo , Fabaceae , Himecromona/metabolismo , Cinética , Lectinas de Plantas , Plantas Medicinales , Análisis de Regresión , Espectrometría de Fluorescencia , Termodinámica
13.
J Neurosurg ; 68(4): 505-17, 1988 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3280746

RESUMEN

A multicenter, randomized placebo-controlled double-blind trial of nimodipine in poor-grade aneurysm patients was carried out in 17 Canadian hospitals. Of 188 patients enrolled in the trial, 32 were excluded for protocol violations and two were excluded due to statistical considerations, leaving 154 patients for valid outcome analysis. Nimodipine treatment was associated with a significantly better outcome (p less than 0.001): 21 (29.2%) of 72 nimodipine-treated patients had a good outcome at 3 months after subarachnoid hemorrhage (SAH) compared to eight (9.8%) of 82 placebo-treated patients. Delayed ischemic deficits from vasospasm alone were significantly less frequent in the nimodipine group (p less than 0.05) with permanent deficits occurring in five nimodipine-treated patients (6.9%) and in 22 placebo-treated patients (26.8%). Improvement in the good outcome rate and reduction in delayed ischemic deficits from vasospasm alone occurred in both Grade 3 and 4 patients, with no difference between nimodipine- and placebo-treated patients being found in Grade 5 patients. Repeat angiography after Day 4 was carried out in 124 patients. There was no significant difference in the incidence of moderate or severe diffuse spasm, which was seen in 64.3% of nimodipine-treated patients and 66.2% of placebo-treated patients. The authors conclude that nimodipine treatment in poor-grade patients with SAH results in an increase in the number of good outcomes and a reduction in the incidence of delayed neurological deterioration due to vasospasm. This effect occurs by a mechanism other than prevention of large-vessel spasm as visualized on angiography.


Asunto(s)
Aneurisma Intracraneal/tratamiento farmacológico , Nimodipina/uso terapéutico , Adolescente , Adulto , Anciano , Antifibrinolíticos/uso terapéutico , Isquemia Encefálica/etiología , Isquemia Encefálica/fisiopatología , Isquemia Encefálica/prevención & control , Angiografía Cerebral , Infarto Cerebral/diagnóstico por imagen , Infarto Cerebral/etiología , Ensayos Clínicos como Asunto , Método Doble Ciego , Humanos , Aneurisma Intracraneal/complicaciones , Aneurisma Intracraneal/mortalidad , Aneurisma Intracraneal/fisiopatología , Ataque Isquémico Transitorio/diagnóstico por imagen , Ataque Isquémico Transitorio/etiología , Ataque Isquémico Transitorio/prevención & control , Persona de Mediana Edad , Nimodipina/efectos adversos , Índice de Severidad de la Enfermedad , Hemorragia Subaracnoidea , Tomografía Computarizada por Rayos X
15.
J Biol Chem ; 261(7): 3013-9, 1986 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-3753974

RESUMEN

A basic lectin (pI approximately 10.0) was purified to homogeneity from the seeds of winged bean (Psophocarpus tetragonolobus) by affinity chromatography on Sepharose 6-aminocaproyl-D-galactosamine. The lectin agglutinated trypsinized rabbit erythrocytes and had a relative molecular mass of 58,000 consisting of two subunits of Mr 29,000. The lectin binds to N-dansylgalactosamine, leading to a 15-fold increase in dansyl fluorescence with a concomitant 25-nm blue shift in the emission maximum. The lectin has two binding sites/dimer for this sugar and an association constant of 4.17 X 10(5) M-1 at 25 degrees C. The strong binding to N-dansylgalactosamine is due to a relatively positive entropic contribution as revealed by the thermodynamic parameters: delta H = -33.62 kJ mol-1 and delta S0 = -5.24 J mol-1 K-1. Binding of this sugar to the lectin shows that it can accommodate a large hydrophobic substituent on the C-2 carbon of D-galactose. Studies with other sugars indicate that a hydrophobic substituent in alpha-conformation at the anomeric position increases the affinity of binding. The C-4 and C-6 hydroxyl groups are critical for sugar binding to this lectin. Lectin difference absorption spectra in the presence of N-acetylgalactosamine indicate perturbation of tryptophan residues on sugar binding. The results of stopped flow kinetics with N-dansylgalactosamine and the lectin are consistent with a simple one-step mechanism for which k+1 = 1.33 X 10(4) M-1 s-1 and k-1 = 3.2 X 10(-2) s-1 at 25 degrees C. This k-1 is slower than any reported for a lectin-monosaccharide complex so far. The activation parameters indicate an enthalpically controlled association process.


Asunto(s)
Metabolismo de los Hidratos de Carbono , Fabaceae/metabolismo , Lectinas/metabolismo , Plantas Medicinales , Termodinámica , Animales , Unión Competitiva , Conformación de Carbohidratos , Cromatografía de Afinidad , Compuestos de Dansilo/metabolismo , Galactosamina/análogos & derivados , Galactosamina/metabolismo , Hemaglutinación , Cinética , Matemática , Peso Molecular , Lectinas de Plantas , Conejos , Espectrometría de Fluorescencia
16.
Planta Med ; 47(3): 191-2, 1983 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17404912
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