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1.
Heliyon ; 10(9): e29989, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38707456

RESUMEN

Objectives: To investigate extracts of the stem bark of Ziziphus jujuba (L.) Gaertn. var. hysudrica Edgew. (Rhamnaceae) for anti-inflammatory activity and isolate the active principle(s). Methods: The dry powder was macerated separately in three types of solvents to prepare methanol extract (ME), ethyl acetate extract (EE), and chloroform extract (CE). Following in vitro anti-inflammatory screening, the most active extract was selected to isolate the active compound. Both, the active extract and isolated compound were further tested on rats using the carrageenan-induced inflammation model. The blood and paw tissue were subjected to qPCR, and histopathology, respectively. Key findings: CE showed comparatively higher anti-inflammatory activity (85.0-95.0 %) in all in vitro assays, except the heat-induced membrane stabilization model (p < 0.05), and upon column chromatography, it yielded a pure crystalline compound. The compound was a pentacyclic triterpenoid (Lupane), named as hydroxymethyl (3ß)-3-methyl-lup-20(29)-en-28-oate (Hussainate). CE (500 mg/kg) and Hussainate (1.0 mg/kg) reduced edema in 5 h after carrageenan administration. The activity of Hussainate was found to be comparable to that of dexamethasone (standard). The possible activity mechanism was the downregulation of tumor necrosis factor-alpha (TNF-α), cyclooxygenase-2 (COX-II), NF-κB, and IL-1ß. Conclusions: This study reveals that chloroform extract of the stem's bark of Z. jujuba may be used to prepare standardized anti-inflammatory herbal products using Hussainate as an active analytical marker. Hussainate may be used as a lead to develop anti-inflammatory drugs.

2.
Eur Rev Med Pharmacol Sci ; 27(23): 11211-11221, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38095371

RESUMEN

OBJECTIVE: Amiodarone (AMD), a drug of choice to treat cardiac arrhythmias, has a narrow therapeutic index (NTI). It inhibits CYP3A4, CYP2C9, and CYP2D6 enzymes. Quercetin (QUE), a pharmacologically important bioflavonoid in vegetables and fruits, is important in treating cardiovascular comorbidities. QUE alters the bioavailability of drugs used concurrently by dual inhibition of P-glycoproteins (P-gp) and cytochrome (CYP) enzyme systems. The current study aimed to investigate the pre-treatment and co-administration effect of QUE on AMD pharmacokinetics in rats. MATERIALS AND METHODS: Two separate animal trials (I and II) were planned to probe the effect of QUE on AMD pharmacokinetics by following previously cited studies. The pre-treatment group received oral doses of QUE for 14 days, and a single dose of AMD on the 15th day. Rats were administered single doses of QUE (20 mg/kg) and AMD (50 mg/kg) concurrently in a carboxymethylcellulose (CMC) in the co-administration study. Blood was collected at pre-determined time points. AMD was quantified by HPLC, and data was analyzed by PK solver software. RESULTS: In the pre-treated group, peak plasma concentration (Cmax) and area under the curve (AUC0-∞) of AMD were increased by 45.52% and 13.70%, respectively, while time to achieve maximum concentration (tmax), half-life (t1/2) and clearance (CL) were declined by 35.72%, 16.75%, and 11.0% respectively compared to the control. In the co-administered group, compared to controls, Cmax and AUC0-∞ were elevated to 12.90% and 7.80%, respectively, while tmax, t1/2, and CL declined by 16.70%, 2.35%, and 13.40%. Further, AMD was increased in lung tissue of both treated groups, relative to the respective controls. CONCLUSIONS: A notable pharmacokinetic drug interaction between QUE and AMD was observed in rats and warrants possible drug interaction study in humans, suggesting AMD dose adjustment specifically in patients with arrhythmia having a pre-treatment history and simultaneous administration of QUE-containing products.


Asunto(s)
Amiodarona , Quercetina , Humanos , Ratas , Animales , Quercetina/farmacología , Amiodarona/farmacología , Distribución Tisular , Interacciones Farmacológicas , Disponibilidad Biológica , Área Bajo la Curva
3.
Eur Rev Med Pharmacol Sci ; 26(3): 1049-1055, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35179772

RESUMEN

OBJECTIVE: The reorganization of cancer services and the increased work burden on health care providers during the COVID-19 pandemic are likely to be associated with significant negative psychological impact. The aim of this study is to evaluate the impact of COVID-19 pandemic on the psychological well-being of oncology clinicians in the Middle East and North Africa (MENA) region. MATERIALS AND METHODS: We randomly invited 1500 oncology clinicians including medical oncologists, clinical oncologists, radiation oncologists and surgical oncologists from 17 countries in the MENA region to complete a web-based survey to determine the level of psychological stress during the COVID-19 pandemic from October 2020 to January 2021. The questionnaire was based on the Perceived Stress Scale (PSS), Generalized Anxiety Disorders Scale (GAD-7) and WHO Well-being Index (WHO-5). The data was analyzed using SPSS version 21 and the difference between groups was measured by t-test and ANOVA. RESULTS: Overall, 520 (35%) clinicians including 368 (71%) males and 152 (29%) females participated in the survey with 247 (47%) participants between the ages of 36 to 45 years. Average score of 29.6 for males and 30.2 on PSS-10, indicative of high-perceived stress in both the genders. Compared to males, females had significantly higher anxiety levels on GAD-7 scale (p=.04), but this difference in stress level and well-being was not observed on PSS-10 (p=.134) and WHO -5 well-being index (p=.709). Clinicians of age 25-35 years had significantly higher anxiety levels on GAD-7 scale (p=.004) and higher stress on PSS (p=.000) as compared to other age groups. Age over 55 years was associated with lower levels of anxiety and stress on GAD-7 and PSS. Oncology clinicians working in public sector experienced significantly lower stress as compared to private sector on PSS scale (p=.041). CONCLUSIONS: Anxiety and stress levels among oncology clinicians have significantly increased in COVID-19 pandemic in the MENA region. Females and young clinicians had higher anxiety and stress, while oncology clinicians over the age of 55 years and working in the public sector reported less stress and anxiety. The general wellbeing of clinicians was well preserved even in a highly stressful and anxious situation.


Asunto(s)
COVID-19/psicología , Oncólogos/psicología , Estrés Psicológico/epidemiología , Adulto , África del Norte/epidemiología , Ansiedad/epidemiología , Femenino , Encuestas Epidemiológicas/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Medio Oriente/epidemiología , Pandemias , Sector Privado , Sector Público
4.
Acta Biol Hung ; 65(3): 355-67, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25194738

RESUMEN

Synthetic seed technology is an alternative to traditional micropropagation for production and delivery of cloned plantlets. Synthetic seeds were produced by encapsulating nodal segments of C. angustifolia in calcium alginate gel. 3% (w/v) sodium alginate and 100 mM CaCl2 · 2H2O were found most suitable for encapsulation of nodal segments. Synthetic seeds cultured on half strength Murashige and Skoog medium supplemented with thidiazuron (5.0 µM) + indole-3-acetic acid (1.0 µM) produced maximum number of shoots (10.9 ± 0.78) after 8 weeks of culture exhibiting (78%) in vitro conversion response. Encapsulated nodal segments demonstrated successful regeneration after different period (1-6 weeks) of cold storage at 4 °C. The synthetic seeds stored at 4 °C for a period of 4 weeks resulted in maximum conversion frequency (93%) after 8 weeks when placed back to regeneration medium. The isolated shoots when cultured on half strength Murashige and Skoog medium supplemented with 1.0 µM indole-3-butyric acid (IBA), produced healthy roots and plantlets with well-developed shoot and roots were successfully hardened off in plastic pots containing sterile soilrite inside the growth chamber and gradually transferred to greenhouse where they grew well with 85% survival rate. Growth performance of 2 months old in vitro-raised plant was compared with in vivo seedlings of the same age. Changes in the content of photosynthetic pigments, net photosynthetic rate (PN), superoxide dismutase and catalase activity in C. angustifolia indicated the adaptation of micropropagated plants to ex vitro conditions.


Asunto(s)
Plantas Medicinales/crecimiento & desarrollo , Semillas/crecimiento & desarrollo , Senna/crecimiento & desarrollo , Adaptación Fisiológica , Catalasa/metabolismo , Proliferación Celular , Clorofila/metabolismo , Fotosíntesis , Reguladores del Crecimiento de las Plantas/farmacología , Plantas Medicinales/efectos de los fármacos , Plantas Medicinales/metabolismo , Regeneración , Semillas/efectos de los fármacos , Semillas/metabolismo , Senna/efectos de los fármacos , Senna/metabolismo , Superóxido Dismutasa , Factores de Tiempo , Técnicas de Cultivo de Tejidos
5.
J Biotechnol ; 184: 219-28, 2014 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-24910973

RESUMEN

A Pichia pastoris transformant carrying the cutinase cDNA of Glomerella cingulata was over-expressed in a 5L bioreactor (2.0L working volume) under fed-batch conditions. Bioreactor experiments rely on varying selected parameters in repeated rounds of optimisation: here these included duration of induction, pH and temperature. Highest cell densities (320gL(-1) wet cell weight) with a cutinase production of 3800mgL(-1) and an activity of 434UmL(-1) were achieved 24h after induction with methanol in basal salt medium (at pH 5 and 28°C). Characterisation of the cutinase showed that it was stable between pH 6 and pH 11, had an optimum pH of 8.0 and retained activity for 30min at 50°C (optimum temperature 25°C).The preferred substrates of G. cingulata cutinase were the medium- to long-chain ρ-nitrophenyl esters of ρ-nitrophenylcaprylate (C8), ρ-nitrophenyllaurate (C12) and ρ-nitrophenylmyristate (C14), with the highest catalytic efficiency, kcat/Km of 7.7±0.7mM(-1)s(-1) for ρ-nitrophenylcaprylate. Microscopic analyses showed that the G. cingulata cutinase was also capable of depolymerising the high molecular weight synthetic polyester, polyethylene terephthalate.


Asunto(s)
Técnicas de Cultivo Celular por Lotes/métodos , Hidrolasas de Éster Carboxílico/biosíntesis , Phyllachorales/enzimología , Proteínas Recombinantes/biosíntesis , Reactores Biológicos , Hidrolasas de Éster Carboxílico/química , Hidrolasas de Éster Carboxílico/metabolismo , Concentración de Iones de Hidrógeno , Phyllachorales/genética , Pichia/genética , Pichia/crecimiento & desarrollo , Tereftalatos Polietilenos/química , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Tensoactivos/química , Temperatura
6.
Acta Biol Hung ; 64(3): 377-84, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24013898

RESUMEN

An in vitro propagation system for Cassia angustifolia Vahl. has been developed. Due to the presence of sennosides, the demand of this plant has increased manyfold in global market. Multiple shoots were induced by culturing nodal explants excised from mature plants on a liquid Murashige and Skoog [8] medium supplemented with 5-100 µM of thidiazuron (TDZ) for different treatment duration (4, 8, 12 and 16 d). The optimal level of TDZ supplemented to the culture medium was 75 µM for 12 d induction period followed by subculturing in MS medium devoid of TDZ as it produced maximum regeneration frequency (87%), mean number of shoots (9.6 ± 0.33) and shoot length (4.4 ± 0.46 cm) per explant. A culture period longer than 12 d with TDZ resulted in the formation of fasciated or distorted shoots. Ex vitro rooting was achieved when the basal cut end of regenerated shoots was dipped in 200 µM indole-3-butyric acid (IBA) for half an hour followed by their transplantation in plastic pots filled with sterile soilrite where 85% plantlets grew well and all exhibited normal development. The present findings describe an efficient and rapid plant regeneration protocol that can further be used for genetic transformation studies.


Asunto(s)
Cassia/crecimiento & desarrollo , Técnicas de Cultivo , Compuestos de Fenilurea/administración & dosificación , Tiadiazoles/administración & dosificación , Medios de Cultivo
7.
Pak J Pharm Sci ; 23(1): 35-41, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20067864

RESUMEN

Imatinib inhibits Bcr-Abl, c-KIT and PDGFR kinases. It is approved for the treatment of chronic myeloid leukemia (CML), gastrointestinal stromal tumors (GIST) and has further therapeutic potential. Male ICR mice were given imatinib PO (50 or 25 mg/kg, 5 doses every 2 h); euthanized 2 h after the last dose administration; plasma, liver, brain, spleen and kidney were collected and imatinib concentration measured by an optimized HPLC method for quantification in tissues. Methanol (1:1 v/v plasma) and pH 4, 40:30:30 (v/v/v) water-methanol-acetonitrile at 5 ml/g (brain) and 10 ml/g (spleen, kidney, liver) ratio was added to the samples, homogenized, sonicated, centrifuged (15,000 rpm, 5 min, 2 degrees C) and the supernatant injected into an Inertsil CN-3 column (4.6 mm x 150 mm, 5 microm) using 64:35:1 (v/v/v) water-methanol-triethylamine (pH 4.8), flow rate 1 ml/min, 25 degrees C. Imatinib eluted at 7.5 min (268 nm). Linearity: 0.1-50 microg/ml; precision, accuracy, inter- and intra-day variability was within 15%. Recovery was above 95% (plasma), 80% (brain) and 90% (kidney, liver, spleen). Imatinib tissue concentrations were 6-8 folds higher than plasma except brain, where the ratio decreased from 0.24 to 0.08 suggesting limited brain penetration, likely due to blood brain barrier efflux transporters. The extensive distribution supports the expansion of therapeutic applications.


Asunto(s)
Antineoplásicos/farmacocinética , Cromatografía Líquida de Alta Presión/métodos , Piperazinas/farmacocinética , Pirimidinas/farmacocinética , Administración Oral , Animales , Antineoplásicos/administración & dosificación , Benzamidas , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Mesilato de Imatinib , Masculino , Ratones , Ratones Endogámicos ICR , Piperazinas/administración & dosificación , Pirimidinas/administración & dosificación , Distribución Tisular
8.
Eur J Drug Metab Pharmacokinet ; 24(2): 127-32, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10510739

RESUMEN

The disposition kinetics of erythromycin were determined in normal and endotoxin-induced febrile rabbits following intravenous injection of a single dose of 10 mg/kg body weight. In febrile rabbits, body weight, blood pH, total lipids and total proteins in plasma remained unchanged, packed cell volume, albumin and the albumin/globulin ratio reduced while glucose and globulins increased significantly. The mean plasma drug concentration was lower under febrile conditions at all the sampling times except at 480 and 720 min after drug administration where the levels remained the same. The values for t1/2elim and MRT of the drug were observed to be prolonged while that of the Clt reduced and Vd increased in the febrile rabbits. The febrile condition resulted in an alteration in the disposition kinetics of erythromycin suggesting an adjustment of the dosage under febrile conditions.


Asunto(s)
Antibacterianos/metabolismo , Recuento de Células Sanguíneas/efectos de los fármacos , Eritromicina/metabolismo , Fiebre/metabolismo , Animales , Peso Corporal/efectos de los fármacos , Endotoxinas , Fiebre/inducido químicamente , Concentración de Iones de Hidrógeno , Conejos , Factores de Tiempo
9.
J Anat ; 187 ( Pt 1): 181-90, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7591979

RESUMEN

A variety of model-based (growth models) and model-free (cubic splines, exponentials) equations were fitted using weighted-nonlinear least squares regression to embryonic growth data from Alligator mississippiensis eggs incubated at 30 and 33 degrees C. Goodness of fit was estimated using a chi 2 on the sum of squared, weighted residuals, and run and sign tests on the residuals. One of the growth models used (Preece & Baines, 1978) was found to be superior to the classical growth models (exponential, monomolecular, logistic, Gompertz, von Bertalanffy) and gave an adequate fit to all longitudinal measures taken from the embryonic body and embryonic mass. However, measurements taken from the head could not be fitted by growth models but were adequately fitted by weighted least squares cubic splines. Data for the stage of development were best fitted by a sum of 2 exponentials with a transition point. Comparison of the maximum growth rates and parameter values, indicated that the growth data at 30 degrees C could be scaled to 33 degrees C to multiplying the time by a scaling factor of 1.2. This is equivalent to a Q10 of about 1.86 or, after solving the Arrhenius equation, an E++ of 46.9 kJmol-1. This may be interpreted as indicating a common rate-limiting step in development at the 2 temperatures.


Asunto(s)
Caimanes y Cocodrilos/embriología , Diferenciación Sexual , Temperatura , Animales , Femenino , Masculino , Matemática , Modelos Biológicos
10.
Arch Int Physiol Biochim ; 92(2): 73-9, 1984 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6208869

RESUMEN

The rate of energy flow in Porcellio spinicornis was investigated in a select group of a laboratory population. The consumption, assimilation and production were calculated to be 1 233, 1 002 and 304 cal/year, respectively, in the male, and 1 261, 1 198 and 429 cal/year, respectively, in the female. Ignoring loss due to mortality, and applying the population density of 2 295 m2 in the laboratory colony, the isopod population should consume 2 861.8 kcal m-2 year-1, resulting in an assimilation of 2 524.5 kcal m-2 year-1 and a total productivity of 841.1 kcal m-2 year-1.


Asunto(s)
Equinodermos/fisiología , Metabolismo Energético , Amoníaco/biosíntesis , Animales , Ingestión de Energía , Femenino , Masculino , Consumo de Oxígeno , Factores Sexuales
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