535 research outputs found
Study on anisotropies and momentum densities in AlN, GaN and InN by positron annihilation
The independent particle model (IPM) coupled with empirical pseudopotential method (EPM) was used to compute the thermalized positron charge densities in specific family of binary tetrahedrally coordinated crystals of formula ANB8-N. Initial results show a clear asymmetrical positron charge distribution relative to the bond center. It is observed that the positron density is maximum in the open interstices and is excluded not only, from the ion cores but also to a considerable degree from the valence bonds. Electron-positron momentum densities are calculated for the (001,110) planes. The results are used to analyze the positron effects in AlN, GaN and InN compounds. Our computational technique provides the theoretical means of interpreting the k-space densities obtained experimentally using the twodimensional angular correlation of annihilation radiation (2D-ACAR)
The correlation between maternal hypomagnesemia and preterm labour
Background: Preterm birth is defined as all births before 37 weeks completed, which is a major cause of neonatal death and significant cause of long term loss of human potential amongst survivors. The objective of this study was to verify the correlation between low maternal serum magnesium level and preterm delivery.Methods: one hundred patients who admitted into the labour room of the hospital due to preterm labour (28-36+6 weeks of gestation) whose etiology could not be explained by etiological factors were enrolled in this prospective case-control study during the period from June 2013 to June 2014. And another 80 women of comparable gestational age who were referred to the consultation clinic of our hospital for achieving prenatal care or for causes other than preterm labour, provided only those whose birth occurred after 37th week considered as a control group. Serum magnesium level was measured in both groups.Results: Women in preterm labour had a significantly reduced serum magnesium level (mean1.552 mg/dl with a S.D. of 0.658 versus 1.81 mg/dl with a SD of 0.735) for those delivered at term (p<0.032). Number of patients with Preterm labour who gave of history of muscle cramps were significantly greater than those delivered at term (p<0.00193). Percentage of patients with preterm labour belonging to low socio-economic class was significantly higher than the upper and middle socio-economic classes (p<0.041).Conclusions: Serum magnesium level can be used as a predicting tool for idiopathic preterm labour
Validated Stability-indicating HPTLC Determination of Baclofen in Bulk Drug, Pharmaceutical Formulations and Real Human Urine and Plasma.
A simple, highly selective and stability-indicating high-performance thin-layer chromatographic method was developed and validated for the analysis of baclofen in bulk powder, pharmaceutical formulations and human urine and in and real human plasma. The method employed TLC aluminum plates precoated with silica gel 60 F254 as the stationary phase. The solvent system consisted of butanol–acetic acid–water (3.0: 0.5: 0.5, v/v/v). This system was found to give compact spots for baclofen (Rf value of 0.54). Densitometric analysis was carried out in the absorbance mode at 238 nm. The linear regression analysis data for the calibration plot showed good linear relationship (r2 = 0.9983) in the concentration range 1.5-7.5 µg per spot. The analytical performance of the method was fully validated, and the results were satisfactory. The limits of detection and quantitation were 0.31 and 1.03 µg per spot, respectively. Baclofen was subjected to acid and alkali hydrolysis, oxidation and photodegradation. The degraded product was well separated from the pure drug. Results indicate that the drug is stable against light and basic conditions. However, additional peaks were observed at Rf value of 0.65 and at Rf value of 0.14 with hydrogen peroxide and hydrochloric acid respectively, indicating that the drug is susceptible to oxidation and acid degradation. The method was applied for the analysis of baclofen in commercial tablets and the results were similar to those obtained using the reference method. As the method could effectively separate the drug from its degradation product, it can be employed as a stability-indicating one. The high sensitivity of the proposed method allowed determination of baclofen in real human urine and plasma
A Generalized Skew of type IV Logistic Distribution
In this paper, we derive, the probability density function (pdf) and cumulative distribution function (CDF) of the skew type IV generalized logistic distribution GSLD IV . The general statistical properties of the GSLD IV . such as: the moment generating function (mgf), characteristic function (ch.f), Laplace and fourier transformations are obtained in explicit form. Expressions for the nth moment, skewness and kurtosis coefficients are discussed. The mean deviation about the mean and about the median are also obtained. We consider the general case by inclusion of location and scale parameters. The results of Asgharzadeh (2013) are obtained as special cases. Graphically illustration of some results have been represented. Further we present a numerical example to illustrate some results of this paper. Keywords: skew type IV generalized logistic distribution, moment generating function, skewness, kurtosis, mean deviation
Desarrollo y caracterización de una nueva formulación nano-lipoosómica de alendronato sódico con un polímero biodegradable
This work was supported by the pharmacological
departmental grant.Background: Alendronate Sodium (ALDS) is the drug of choice for treatment of osteoporosis. However,
50% of the osteoporotic patients ceased the treatment within the first year due to its potential side effect
on the gastrointestinal tract (GIT).
Objective: The current study aimed to utilize nanotechnology to develop a nano-oral liposomal preparation
containing biodegradable polymer (Starch) that enhance the drug prosperities.
Methods: Nanoliposomes of ALDS were prepared using different concentrations of solubilized starch
(0.1 - 0.5 g ) by thin film hydration method. A new method of alendronate quantitative determination
was used to overcome the obstacle of its determination by using a new highly sensitive derivatization
method. The selected formula was visualized using TEM, in vitro release studies and Stability study was
also carried out.
Furthermore, ulcerogenicity studies were performed to compare between the optimum prepared formula
and a standard nonliposomal ALDS.
Results: Six nano-oral liposomal formulations were prepared with zeta potentials ranging from -12 mV
to -39 mV and a particle size ranging from 94 nm to 298 nm. The encapsulation efficiency studies demonstrated
that the amount of ALDS entrapped within liposomes increased with increasing starch concentration.
The stability studies confirmed the role of starch in increasing the stability of the prepared
liposomes. In vitro release studies have demonstrated a relative delay in ALDS releases from the liposome
core.
Ulcerogenicity studies proofed that the prepared formula has a significant gastric tolerance.
Conclusion: a novel liposomal formula of ALDS was developed with better tolerability. However, further
clinical investigations are necessary to evaluate its therapeutic effectiveness.Antecedentes: El alendronato sódico (ALDS) es el fármaco de elección para el tratamiento
de la osteoporosis. Sin embargo, el 50% de los pacientes osteoporóticos cesaron el tratamiento
en el primer año debido a su posible efecto secundario en el tracto gastrointestinal (GIT).
Objetivo: El presente estudio tiene como objetivo utilizar la nanotecnología para desarrollar una preparación
liposomal nano-oral que contiene polímero biodegradable (almidón) que mejoran la prosperidad de la droga.
Métodos: Se prepararon nanoliposomas de ALDS utilizando diferentes concentraciones de almidón solubilizado
(0,1 - 0,5 g) mediante un método de hidratación de película delgada. Se utilizó un nuevo
método de determinación cuantitativa de alendronato para superar el obstáculo de su determinación utilizando un nuevo método de derivatización altamente sensible.
La fórmula seleccionada se visualizó utilizando TEM, estudios de
liberación in vitro y se realizó también un estudio de estabilidad.
Además, los estudios de ulcerogenicidad se realizaron para comparar
entre la fórmula óptima preparada y un estándar no liposomal ALDS.
Resultados : Se prepararon seis formulaciones liposomales
nano-orales con potenciales zeta que oscilaban entre -12 mV
y -39 mV y un tamaño de partícula que variaba de 94 nm a 298
nm. Los estudios de eficacia de la encapsulación demostraron
que la cantidad de ALDS atrapada dentro de los liposomas aumentaba
con el aumento de la concentración de almidón. Los
estudios de estabilidad confirmaron el papel del almidón en
el aumento de la estabilidad de los liposomas preparados. Los
estudios de liberación in vitro han demostrado un retraso relativo
en las liberaciones de ALDS del núcleo de liposomas.
Los estudios de ulcerogenicidad demostraron que la fórmula
preparada tiene una tolerancia gástrica significativa.
Conclusión: se desarrolló una nueva fórmula liposomal de ALDS
con mejor tolerabilidad. Sin embargo, otras investigaciones clínicas
son necesarias para evaluar su efectividad terapéutica
Performance of Five Species of Phytoseiid Mites (Acari: Phytoseiidae) on Bactrocera zonata Eggs (Diptera: Tephritidae) as a Factitious Food
Development, survival and reproduction of the generalist predatory mites, Amblyseius largoensis (Muma), Neoseiulus barkeri (Hughes), Typhlodromips swirskii (Athias-Henriot), Proprioseiopsis kadii (El-Halawany and Abdel-Samad) and Cydnosus negevi (Swirski and Amitai) were assessed when fed on eggs of Bactrocera zonata (Saunders) (Diptera: Tephritidae) as a factitious food. For N. barkeri and P. kadii, the development was faster, while the reproduction was higher in N. barkeri and A. largoensis than for P. kadii. Survival of immatures of T. swirskii and C. negevi was low on eggs of B. zonata and all failed to develop beyond the protonymphal stage.
A total of 35.4, 31.2 and 19.6 eggs per female, respectively, were obtained when N. barkeri, A. largoensis and P. kadii were fed B. zonata eggs. A diet of the peach fruit fly eggs provided the longest female longevity and highest mean total fecundity, which resulted in the highest net reproductive rate (Ro=34.61 and 32.78) and doubling time (DT=1.53 and 1.60) for N. barkeri and A. largoensis, respectively
Novel quinazoline and acetamide derivatives as safe anti-ulcerogenic agent and anti-ulcerative colitis activity
Two novel quinazoline derivatives named as; 3-[(4-hydroxy-3-methoxy-benzylidene)-amino]-2-p-tolyl3H-quinazolin-4-one
(5) and 2-p-Tolyl-3-[3,4,5-trimethoxy-benzylidene-amino]-3H-quinazolin-4-one
(6) in addition to one acetamide derivative named as 2-(2-Hydroxycarbonylphenylamino)-N-(4-
aminosulphonylphenyl) 11 were synthesized, and evaluated for their anti-ulcerogenic & AntiUlcerative
colitis activities.
All of the three compounds showed curative activity against acetic acid induced ulcer model at a dose
of 50 mg/kg, they produced 65%, 85% & 57.74% curative ratio for compounds 5, 6 & 11 respectively. The
effect of the tested compounds 5, 6 & 11 at dose 50 mg/kg were significantly (P < 0.01) more effective
than dexamesathone (0.1 mg/kg) in reducing all parameters.
Compounds showed curative activity of for peptic ulcer (induced by absolute alcohol (at a dose of 50
mg/kg, it produced Curative of control ulcer 56.00%, 61.70% & 87.1% for compounds 5, 6 & 11 respectively
at dose 50 mg/kg, while the standard drug (Omeprazole 20 mg/kg) produced 33.3%. In both tests, the
activity of our target compounds were higher than the standard drugs used for treatment of peptic ulcer
and ulcerative colitis. No side effects were reported on liver and kidney functions upon prolonged oral
administration of this compounds
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