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1.
Neural Comput Appl ; 35(20): 14591-14609, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35250181

RESUMEN

A SARS-CoV-2 virus-specific reverse transcriptase-polymerase chain reaction (RT-PCR) test is usually used to diagnose COVID-19. However, this test requires up to 2 days for completion. Moreover, to avoid false-negative outcomes, serial testing may be essential. The availability of RT-PCR test kits is currently limited, highlighting the need for alternative approaches for the precise and rapid diagnosis of COVID-19. Patients suspected to be infected with SARS-CoV-2 can be assessed using chest CT scan images. However, CT images alone cannot be used for ruling out SARS-CoV-2 infection because individual patients may exhibit normal radiological results in the primary phases of the disease. A machine learning (ML)-based recognition and segmentation system was developed to spontaneously discover and compute infection areas in CT scans of COVID-19 patients. The computable assessment exhibited suitable performance for automatic infection region allocation. The ML models developed were suitable for the direct detection of COVID-19 (+). ML was confirmed to be a complementary diagnostic technique for diagnosing COVID-19(+) by forefront medical specialists. The complete manual delineation of COVID-19 often requires up to 225.5 min; however, the proposed RILML method decreases the delineation time to 7 min after four iterations of model updating.

2.
J Hazard Mater ; 375: 281-289, 2019 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-31078988

RESUMEN

Zea mays L. dry husk extract was used to bio synthesize copper oxide nanoparticles. Red coloured cubic Cu2O nanoparticles were obtained for the first time via this simple, eco- friendly, green synthesis route. The Cu2O nanoparticles were thermally oxidized to pure monoclinic CuO nanoparticles at 600 °C. The phases of the copper oxides were confirmed from the x-ray diffraction (XRD) studies. The nanoparticle sizes as obtained from high resolution transmission electron microscope (HRTEM) analysis range from 10 to 26 nm, 36-73 nm and 30-90 nm for the unannealed Cu2O, 300 °C and 600 °C annealed CuO respectively. The values of the bandgap energies obtained from diffuse reflectance of the nanoparticles are 2.0, 1.30 and 1.42 eV respectively for the unannealed, 300 °C, and 600 °C annealed copper oxide nanoparticles. The 600 °C annealed copper oxide nanoparticles showed 91% and 90% degradation ability for methylene blue dye (BM) and textile effluent (TE) respectively under visible light irradiation. While CuO_300 is more effective to inhibit the growth of Escherichia coli 518,133 and Staphylococcus aureus 9144, Cu2O is better for Pseudomonas aeruginosa and Bacillus licheniformis. The results confirm the photo-catalytic and anti-microbial effectiveness of the copper oxide nanoparticles.


Asunto(s)
Antibacterianos/metabolismo , Cobre/metabolismo , Nanopartículas del Metal , Eliminación de Residuos Líquidos/métodos , Zea mays/metabolismo , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Catálisis , Cobre/química , Cobre/farmacología , Cobre/efectos de la radiación , Tecnología Química Verde , Residuos Industriales , Nanopartículas del Metal/química , Nanopartículas del Metal/efectos de la radiación , Azul de Metileno/química , Fotólisis , Textiles , Contaminantes Químicos del Agua/química
3.
J Hazard Mater ; 380: 120900, 2019 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-31326841

RESUMEN

This study reports on the biodegradation of free cyanide (FCN) by cyanide degrading bacteria (CDB) that were isolated from mining wastewater and thiocyanate containing wastewater. The performance of these isolates was compared to cryopreserved CDBs that were used in previous studies. The performance of the isolates to degrade FCN was studied in batch cultures. It was observed that the CDB from the thiocyanate wastewater showed higher biodegradation rates (2.114 g CN-. L-1.O.D600 nm-1.h-1) compared to the isolates from the mining wastewater. The isolates from the cryopreserved CDBs and from the mining wastewater achieved a biodegradation rate of 1.285 g CN- L-1.O.D600 nm-1.h-1 and 1.209 g CN-.L-1.O.D600 nm-1.h-1, respectively. This study demonstrated that the source of the organisms plays a significant role on FCN biodegradation.


Asunto(s)
Bacterias/metabolismo , Biodegradación Ambiental , Cianuros/metabolismo , Contaminantes Químicos del Agua/metabolismo , Minería , Aguas Residuales
4.
Life Sci ; 60(6): 413-24, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9031688

RESUMEN

The effect of endotoxin administration on gentamicin pharmacokinetics in young adult (2-3 months) and old (22-24 months) rats was studied. Gentamicin (3 mg/kg, iv) was administered 24 hours after an endotoxin challenge (5 mg/kg, ip). Some blood biochemical parameters, viz. urea, AST, GGT activities in addition to PCV and Hb concentration and creatinine clearance were also measured. In young animals, endotoxin caused prolongation in gentamicin half life (t1/2), increased area under the plasma concentration-time curve (AUC) and reduced total body clearance (ClB) and volume of distribution (Vd). Endotoxin effects in the old rats were qualitatively similar to those induced in the young but were more pronounced. They included more than 10 fold increase in the t1/2 and AUC. In addition, a rising early phase in gentamicin plasma concentration was noticed in old rats treated with endotoxin which was, probably, due to an early redistribution process of gentamicin. The results indicate that aging and endotoxin, individually, can significantly alter gentamicin pharmacokinetics in the rat. These alterations were exacerbated when endotoxemia was induced in old rats.


Asunto(s)
Envejecimiento/metabolismo , Antibacterianos/farmacocinética , Endotoxemia/metabolismo , Endotoxinas/farmacología , Gentamicinas/farmacocinética , Animales , Antibacterianos/sangre , Glucemia/metabolismo , Proteínas Sanguíneas/metabolismo , Peso Corporal , Creatinina/metabolismo , Ingestión de Alimentos , Endotoxinas/administración & dosificación , Gentamicinas/sangre , Hematócrito , Hemoglobinas/análisis , Masculino , Ratas , Ratas Wistar , Transferasas/sangre , Urea/sangre
5.
Life Sci ; 62(15): 1361-9, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9566778

RESUMEN

Gentamicin (G) treatment (5, 20, 40 and 80 mg kg[-1] day[-1] given intramuscularly for 6 days) was shown to cause a dose-related platelet proaggregatory effect in mouse pial microcirculation. This was associated with a reduction in mouse renal function, indicated by high plasma creatinine and urea concentrations. When G was given at the same doses but as a single injection, it caused no change in renal function or platelet aggregation. Gentamicin (20 and 80 mg kg/day, given intramuscularly for 6 days) significantly (P < 0.05) impeded the platelet antiaggregatory effect of acetylsalicylic acid (100 mg kg[-1], intraperitoneally).


Asunto(s)
Aspirina/farmacología , Gentamicinas/farmacología , Piamadre/irrigación sanguínea , Inhibidores de Agregación Plaquetaria/farmacología , Agregación Plaquetaria/efectos de los fármacos , Animales , Arteriolas/efectos de los fármacos , Interacciones Farmacológicas , Masculino , Ratones
6.
Reprod Toxicol ; 11(2-3): 191-9, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9100292

RESUMEN

Rhazya stricta is a medicinal plant traditionally used in the treatment of diabetes mellitus, inflammation, and helminthiasis. Our objective was to determine if the plant extract has any effect on fetal development in the rat. A lyophilized extract of the plant was administered daily on three consecutive gestation days (GD) covering the period of preimplantation and organogenesis. The fetuses were examined on GD 20. Higher doses (5.0 or 8.0 g/kg) of R. stricta generally caused a reduction in maternal weight gain, compared to controls, whereas the lower doses (0.5 to 2.0 g/kg) did not. Treatment on GD 1, 2, 3, or 7, 8, 9 had no effect on the fetal weight. Treatment on later days GD 8, 9, 10, or 10, 11, 12, or 13, 14, 15 reduced both the number of live fetuses and their weight. Pronounced intrauterine growth retardation (IUGR) was observed in groups treated at later stages, particularly in the high dose groups. Extreme resorption characterized R. stricta treatment on GD 10, 11, and 12. Examination of the conceptus 24 h after R. stricta treatment indicated retarded placental development associated with hypovascularity, which possibly contributed to the IUGR and fetal death. The incidence of malformations such as micromelia, adactyly, maxillary-mandibular hypoplasia, protruding tongue, and edema, did not reach statistical significance. Except perhaps for a generalized growth retardation, no skeletal malformations were obvious. These observations are suggestive of potential fetal toxicity of R. stricta if taken during pregnancy.


Asunto(s)
Retardo del Crecimiento Fetal/inducido químicamente , Feto/efectos de los fármacos , Plantas Medicinales , Teratógenos/toxicidad , Animales , Peso Corporal , Cromatografía Líquida de Alta Presión , Femenino , Reabsorción del Feto/inducido químicamente , Tamaño de los Órganos , Placenta/efectos de los fármacos , Placenta/patología , Extractos Vegetales/química , Extractos Vegetales/toxicidad , Embarazo , Ratas , Ratas Wistar
7.
Pharmacol Biochem Behav ; 59(2): 547-50, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9477006

RESUMEN

Immobility induced by forced swimming is well known as an animal model of depression. Using this paradigm, we have, in the present work, tested the possibility that the medicinal plant Rhazya stricta, which has previously been found to affect the monoamine oxidase inhibitory activity in rat brain, may have an antidepressant-like action. Rats were pretreated with various doses (0.025-6.4 g/kg) of the lyophilized extract of the plant leaves, or with desipramine (10, 20, and 40 mg/kg) and were subjected to the forced swimming test. The results indicated that the plant extract produced a biphasic (bell-shaped) effect on the immobility time. The lower doses (0.1, 0.2, and 0.4 g/kg) elicited a highly significant and inversely dose-dependent decrease in immobility time, and the higher doses (0.8, 1.6, and 6.4 g/kg) showed a dose-dependent decrease in immobility time. Under the same experimental conditions desipramine (20 and 40 mg/kg) produced dose-dependent significant decreases in immobility time. Following administration of R. stricta (6.4 g/kg) the immobility time recovered progressively with time, and 4 h after its administration the immobility time was about 70% of the control level (statistically insignificant). It is concluded that R. stricta extract [or component(s) thereof] may possess an antidepressant-like effect.


Asunto(s)
Antidepresivos/farmacología , Actividad Motora/efectos de los fármacos , Plantas Medicinales/química , Animales , Antidepresivos Tricíclicos/farmacología , Desipramina/farmacología , Relación Dosis-Respuesta a Droga , Masculino , Inhibidores de la Monoaminooxidasa/farmacología , Extractos Vegetales/farmacología , Ratas , Ratas Wistar , Natación
8.
Pharmacol Biochem Behav ; 64(3): 455-60, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10548255

RESUMEN

The effect of acute and chronic treatment of rats with a lyophilized extract of the leaves of the medicinal plant Rhazya stricta on total and ambulatory activity was studied. Given acutely at single oral doses of 1, 2, 4, and 8 g/kg, the extract produced dose-dependent decreases in total activity and ambulatory activity. Diazepam (20 mg/kg, orally) produced a decrease in rat activity comparable to that produced by a dose of 1 g/kg of the extract. When given daily at an oral dose of 2 g/kg for 21 consecutive days, the extract produced, on the last day of treatment, significant decrease in activity amounting to about 30% of control activity levels. Subcutaneous (SC) treatment of rats with caffeine (7.5, 15, and 30 mg/kg), dose-dependently and significantly increased total activity and ambulatory activity. These effects were dose-dependently attenuated when the extract was given concomitantly with caffeine at oral doses of 1, 2, and 4 mg/kg. Treatment of rats with zoxazolamine alone (10, 20, or 40 mg/kg, SC) or R. Stricta (1 and 4 g/kg orally) alone significantly decreased total and ambulatory activities. Concomitant treatment with zoxazolamine and R. Stricta decreased the rats activity to a greater degree than with either treatment given alone.


Asunto(s)
Actividad Motora/efectos de los fármacos , Plantas Medicinales/química , Animales , Ansiolíticos/farmacología , Cafeína/farmacología , Estimulantes del Sistema Nervioso Central/farmacología , Diazepam/farmacología , Dopamina/fisiología , Interacciones Farmacológicas , Masculino , Relajantes Musculares Centrales/farmacología , Extractos Vegetales/farmacología , Ratas , Ratas Wistar , Factores de Tiempo , Zoxazolamina/farmacología
9.
Pharmacol Biochem Behav ; 59(3): 671-5, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9512070

RESUMEN

Rhazya stricta leaves, which have both antidepressant and sedative properties in animal models, are widely used in folk medicine in the Arabian peninsula. In this study, the effects of oral administration of leaf extracts on rat brain tribulin levels [endogenous monoamine oxidase (MAO) A and B inhibitory activity], were determined. In an acute study, low doses brought about an increase in MAO A inhibitory activity, while intermediate doses caused a significant reduction. The highest doses had no significant effects on activity. There were no significant effects on MAO B inhibitory activity at any dose. Subchronic administration (21 days) caused a significant decrease in MAO A inhibitory activity, most prominent at low dosage, and an increase in MAO B inhibitory activity. Acute intramuscular administration also resulted in a similar pattern. Such paradoxical effects were at least partially explained when different extracts of the leaves were used; a weakly basic chloroform fraction caused an increase in MAO A inhibitory activity, whereas butanol extracts brought about a decrease. These fractions had no significant effects on MAO B inhibitory activity. The findings show that Rhazya stricta leaves contain at least two different components that affect MAO inhibitory activity in opposite directions. It may be that the antidepressant and sedative actions of the plant are explicable in terms of these different components.


Asunto(s)
Química Encefálica/efectos de los fármacos , Isatina , Inhibidores de la Monoaminooxidasa/metabolismo , Plantas Medicinales/química , Animales , Encéfalo/efectos de los fármacos , Encéfalo/enzimología , Cromatografía Líquida de Alta Presión , Inyecciones Intramusculares , Masculino , Monoaminooxidasa/metabolismo , Extractos Vegetales/administración & dosificación , Extractos Vegetales/farmacología , Ratas , Ratas Wistar , Espectrofotometría Ultravioleta
10.
J Pharm Pharmacol ; 49(5): 500-4, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9178184

RESUMEN

This work examines some effects of the crude ethanolic extract of the medicinal plant Cassia italica, given at single oral doses of 0.25, 0.5 or 1 g kg-1, on the central nervous system in mice. Several models of nociception have been used to examine the analgesic effect of the extract. HPLC fingerprinting of the extract was performed to ensure uniformity of the extract material used. In treated mice, the extract caused dose-related inhibition of acetic acid-induced abdominal constriction, and in the formalin test of antinociception the extract reduced formalin-induced pain in the second (late) but not in the first (early) phase of the pain. Treatment with the extract at doses of 0.5 and 1 g kg-1 significantly increased the reaction time in the hot-plate and warm-water tail-flick tests. Naloxone was ineffective in antagonizing the analgesic effect of C. italica on tail-flick and abdominal constriction tests, possibly indicating that the effect occurs via non-opiate pathways. The C. italica extract caused slight dose-related impairment of motor control which was significant only at a dose of 1 g kg-1. Treatment at the three doses used did not affect the rectal temperature of normothermic mice, but was effective in significantly reducing the rectal temperature of hyperthermic rats, 0.5 and 1 h (but not 6 h) after administration of the extract at doses of 0.5 and 1 g kg-1. The extract also produced progressive diminution in the ambulatory and total activity of treated mice for up to 2 h after administration. It is concluded that the crude ethanolic extract of C. italica has CNS depressant properties, manifested as antinociception and sedation.


Asunto(s)
Cassia/química , Sistema Nervioso Central/efectos de los fármacos , Extractos Vegetales/farmacología , Plantas Medicinales , Animales , Temperatura Corporal/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Interacciones Farmacológicas , Etanol/química , Masculino , Ratones , Ratones Endogámicos , Actividad Motora/efectos de los fármacos , Naloxona/farmacología , Antagonistas de Narcóticos/farmacología , Nociceptores/efectos de los fármacos , Desempeño Psicomotor/efectos de los fármacos , Ratas , Recto , Sueño/efectos de los fármacos
11.
J Pharm Pharmacol ; 49(3): 301-4, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9231350

RESUMEN

This work examines the effect on the weights of vital body organs, on blood biochemical variables, on neuromuscular coordination and on cerebral microcirculation of aqueous extracts of Teucrium stocksianum, given to mice in drinking water at concentrations of 2 and 4% for 56 days. The treatment caused progressive impairment of neuromuscular coordination, as evidenced by the time spent on the rota-rod. After photochemical challenge, the time for first observable platelet aggregation in arterioles was shorter than for the control group by 22 and 45% in the 2 and 4% T. stocksianum-treated groups, respectively. Platelet aggregation on the venular side was not affected by the treatment nor were microvascular diameters. Treatment with the plant extract produced no statistically significant effect on the plasma biochemical variables that are considered indices of liver and kidney function. Histologically, brains obtained from mice treated with T. stocksianum showed loss of cerebellar Purkinje cells. Although it is likely that the accelerated platelet aggregation might have contributed to an ischaemic effect which could, at least in part, have caused the cytotoxicological changes, this does not exclude the possibility of a direct cytotoxicological effect of the plant extract. Further pharmacological and toxicological investigations on Teucrium species seem warranted.


Asunto(s)
Encéfalo/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Extractos Vegetales/toxicidad , Animales , Peso Corporal/efectos de los fármacos , Encéfalo/irrigación sanguínea , Encéfalo/patología , Luz , Masculino , Ratones , Microcirculación/efectos de los fármacos , Microcirculación/efectos de la radiación , Actividad Motora/efectos de los fármacos , Músculo Esquelético/inervación , Músculo Esquelético/fisiología , Tamaño de los Órganos/efectos de los fármacos , Agregación Plaquetaria/efectos de los fármacos , Agregación Plaquetaria/efectos de la radiación , Células de Purkinje/efectos de los fármacos
12.
J Pharm Pharmacol ; 48(5): 545-50, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8799884

RESUMEN

Although medicinal plants are used as antispasmodic agents in folk medicine there have been no scientific studies of the phytochemical composition and usefulness of these plants for such treatment. Extracts of 23 plants used in the traditional medicine of the United Arab Emirates were tested for their effects on intestinal smooth muscle activity. Most of the plants tested caused stimulation followed by inhibition of the motility of the rabbit jejunum and guinea-pig ileum. The inhibitory effect of plants that had EC50 values < 1 mg was confirmed in-vivo using the gastrointestinal transit time test. These plants were phytochemically screened for their secondary constituents. The effect of Rhazya stricta was investigated, particularly in relation to acetylcholine effect. The results indicated the potential of some of the plants, especially Rhazya stricta, as a source of antispasmodic agents.


Asunto(s)
Músculo Liso/efectos de los fármacos , Parasimpatolíticos/farmacología , Extractos Vegetales/farmacología , Plantas Medicinales/química , Acetilcolina/farmacología , Animales , Atropina/farmacología , Sinergismo Farmacológico , Motilidad Gastrointestinal/efectos de los fármacos , Cobayas , Íleon/efectos de los fármacos , Técnicas In Vitro , Yeyuno/efectos de los fármacos , Masculino , Ratones , Contracción Muscular/efectos de los fármacos , Parasimpatolíticos/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Conejos , Emiratos Árabes Unidos
13.
J Pharm Pharmacol ; 48(10): 1098-102, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8953516

RESUMEN

Because of the widespread use of T. stocksianum (Boiss) in herbal medicine and reports of the toxicity of Teucrium chamaedrys to man, the effects of acute (2 and 4 g kg-1 single dose) and chronic (4% in lieu of drinking water for 48 days) administration of an aqueous extract of T. stocksianum has been studied in rats. After acute administration no change was found in reduced liver glutathione content, plasma total protein concentration or the enzyme activities of aminotransferase or gamma glutamyl transferase. After chronic administration, no change was noticed in the plasma concentrations of total protein, total bilirubin, creatinine, urea, glucose, triglycerides, calcium or phosphorus or the enzyme activities of aminotransferase, alanine aminotransferase, creatinine kinase, gamma glutamyl transferase or lactate dehydrogenase. There was no change in food or water intake or output of urine or faeces; the body weight of the treated animals was, however, slightly reduced. No change was observed in the weight of vital body tissues. Histological examination revealed occasional hepatic 'apoptosis' and cerebral neuronal loss in the cortex and hippocampus in treated animals; focal loss of Purkinje cells in the cerebellum was particularly noticed. The results did not indicate a major hepatotoxic effect of acute or chronic administration of T. stocksianum, unlike other Teucrium spp. We report a neurotoxic effect, however, which warrants monitoring of neurological function in people taking this plant.


Asunto(s)
Plantas Medicinales , Animales , Encéfalo/efectos de los fármacos , Encéfalo/patología , Hígado/efectos de los fármacos , Hígado/patología , Masculino , Extractos Vegetales/toxicidad , Ratas , Ratas Wistar
14.
J Pharm Pharmacol ; 52(10): 1297-300, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11092575

RESUMEN

The effect of treatment with the medicinal plant Rhayva stricta Decne, on monoamine oxidase (MAO) and cholinesterase activity, and on the concentration of brain biogenic amines was studied in rats. R. stricta extract, at doses of 0.2 and 0.5 g kg(-1), significantly (P < 0.05-0.01) increased the hepatic and cerebral activity of MAO by 36-127%. The higher doses used (2.0 and 8.0 g kg(-1)) produced smaller (10-26%) and statistically insignificant increases in MAO activity in liver and brain. Cholinesterase activity in blood, liver and brain was not significantly influenced by treatment with R. stricta. The concentrations of the measured biogenic amines (noradrenaline, adrenaline, 5-hydroxytryptamine and dopamine) were significantly lowered in rats treated with R. stricta. The observed increase in MAO activity may be responsible for the lowered biogenic amines levels and may, in part, be responsible for the pharmacological effects of R. stricta extract in rats.


Asunto(s)
Aminas Biogénicas/metabolismo , Encéfalo/efectos de los fármacos , Colinesterasas/efectos de los fármacos , Hígado/efectos de los fármacos , Monoaminooxidasa/efectos de los fármacos , Extractos Vegetales/farmacología , Animales , Encéfalo/metabolismo , Colinesterasas/metabolismo , Hígado/metabolismo , Masculino , Monoaminooxidasa/metabolismo , Plantas Medicinales , Ratas , Ratas Wistar
16.
J Ethnopharmacol ; 31(3): 333-7, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2056761

RESUMEN

The aqueous extract of Albizzia anthelmintica bark at 10-150 g/kg orally showed no toxicity and high anthelmintic activity (68-100%) against experimental Hymenolepis diminuta infection in albino rats. The water extract from A. lebbek bark at 10-100 g/kg orally was less effective against the cestode and was toxic to rats at the highest dose tested (150 g/kg).


Asunto(s)
Himenolepiasis/tratamiento farmacológico , Extractos Vegetales/uso terapéutico , Plantas Medicinales/análisis , Animales , Femenino , Himenolepiasis/parasitología , Masculino , Ratas , Sudán
17.
J Ethnopharmacol ; 17(3): 205-11, 1986 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3807384

RESUMEN

Grewia bicolor is a small tree, parts of which are used in Sudanese traditional medicine for treating pustulent skin lesions, internally on indication of a delayed afterbirth and sometimes as a tranquilizer. A phytochemical investigation of Grewia bicolor gave the following results: the petroleum ether extract afforded beta-sitosterol and beta-sitosterol- and triterpene esters, and the triterpenes lupeol and betulin. The methanol extract afforded: beta-sitosterol-glucoside and three alkaloids, harman, 6-methoxyharman and 6-hydroxyharman. The latter is the main alkaloid. The methanol extract shows activity against gram-positive and gram-negative organisms and causes a strong contraction of the isolated rat uterus which can be blocked by methysergide.


Asunto(s)
Plantas Medicinales , Animales , Antibacterianos , Bacterias/efectos de los fármacos , Femenino , Harmina/análogos & derivados , Harmina/análisis , Técnicas In Vitro , Extractos Vegetales/análisis , Extractos Vegetales/farmacología , Ratas , Sitoesteroles/análisis , Esteroles/análisis , Sudán , Terpenos/análisis , Útero/efectos de los fármacos
18.
J Ethnopharmacol ; 43(2): 141-7, 1994 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-7967654

RESUMEN

The effect of R. stricta water extract on glucose homeostasis was studied in normal and streptozotocin diabetic rats. R. stricta had no effect on fasting glucose levels in normal and diabetic rats up to 7 h after its oral administration. In normal and diabetic rats R. stricta did not produce any significant effect on an oral glucose tolerance test (OGTT). Chronic administration of R. stricta in drinking water for 37 days did not produce any effect on the parameters of glucose homeostasis studied (plasma glucose, body weight, feed and fluid intake and plasma fructosamine) in the normal or diabetic phase of the experiment. The LD50 of R. stricta in mice was 2.36 g/kg body weight of the lyophilised extract and a daily administration of R. stricta to rats for 5 days did not produce any signs of organ damage.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Glucosa/metabolismo , Plantas Medicinales , Administración Oral , Animales , Peso Corporal/efectos de los fármacos , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/metabolismo , Ayuno , Femenino , Prueba de Tolerancia a la Glucosa , Homeostasis/efectos de los fármacos , Dosificación Letal Mediana , Masculino , Ratones , Medio Oriente , Ratas , Ratas Wistar , Estreptozocina
19.
J Ethnopharmacol ; 81(1): 121-7, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12020936

RESUMEN

Salvia aegyptiaca L. is used for treating various unrelated conditions that include nervous disorders, dizziness, trembling, diarrhoea and piles. This work examines some effects of the crude acetone and methanol extracts of the plant given at single oral doses of 0.25, 0.5, 1 or 2 g/kg, on the central nervous system (CNS) in mice. The extracts were also tested for anti-inflammatory and antipyretic actions. Several models of nociception have been used to examine the analgesic effect of the extract. In treated mice, the extracts caused dose-related inhibition of acetic acid-induced abdominal constriction, and significantly reduced formalin-induced pain. Treatment with the extracts at doses of 0.5 and 1 g/kg significantly increased the reaction time in the hot-plate test. In treated mice both extracts caused significant and dose-related impairment of the sensorimotor control and motor activity. Treatment with both extracts did not significantly affect the rectal temperature of normothermic mice. The methanol extract (0.5 and 1.0 g/kg) did not affect the rectal temperature of hyperthermic mice, but the acetone extract was effective in significantly reducing the rectal temperature of hyperthermic mice, 0.5 and 1 h after administration of the extract at doses of 0.25-2 g/kg. It is concluded that the crude methanol and acetone extracts of S. aegyptiaca have CNS depressant properties, manifested as antinociception and sedation. Both extracts have some anti-inflammatory and antipyretic actions. On the whole, the acetone extract appeared to be slightly more effective than the methanol extract in this regard.


Asunto(s)
Sistema Nervioso Central/efectos de los fármacos , Extractos Vegetales/farmacología , Salvia/química , Acetona , Analgésicos no Narcóticos/administración & dosificación , Analgésicos no Narcóticos/farmacología , Analgésicos no Narcóticos/uso terapéutico , Animales , Antiinflamatorios/administración & dosificación , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Temperatura Corporal/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Masculino , Metanol , Ratones , Actividad Motora/efectos de los fármacos , Dolor/inducido químicamente , Dolor/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/administración & dosificación , Extractos Vegetales/uso terapéutico , Desempeño Psicomotor/efectos de los fármacos
20.
J Ethnopharmacol ; 28(3): 285-92, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2335956

RESUMEN

Intraperitoneal administration of the ethanol extract of Grewia bicolor root (300 mg/kg) to rats in early pregnancy (+1-4 days) did not affect the number of conception sites, but significantly increased resorption. In late pregnancy (+19-20 days), the extract (300 mg/kg) did not affect duration of the gestation period; however, 400 mg/kg was lethal to all mother rats. The active compound, apparently a peptide, exerted a serotonin-like effect on rat uterus, rat fundus and rabbit jejunum. All these effects were abolished by methysergide. A transient serotonin-like rise in cat blood pressure was produced by the active fraction and this effect was also blocked by cyproheptadine.


Asunto(s)
Músculo Liso/efectos de los fármacos , Extractos Vegetales/toxicidad , Animales , Presión Sanguínea/efectos de los fármacos , Gatos , Femenino , Muerte Fetal/inducido químicamente , Inyecciones Intraperitoneales , Inyecciones Intravenosas , Masculino , Contracción Muscular/efectos de los fármacos , Embarazo , Conejos , Ratas , Ratas Endogámicas , Útero/efectos de los fármacos
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