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91.
Taishi Higashi Anna Tajima Naoko Ohshita Tatsunori Hirotsu Irhan Ibrahim Abu Hashim Keiichi Motoyama Sawako Koyama Ruriko Iibuchi Shiuhei Mieda Kenji Handa Tomoaki Kimoto Hidetoshi Arima 《AAPS PharmSciTech》2015,16(6):1290-1298
To achieve the potent therapeutic effects of human immunoglobulin G (IgG), highly concentrated formulations are required. However, the stabilization for highly concentrated human IgG is laborious work. In the present study, to investigate the potentials of polypseudorotaxane (PPRX) hydrogels consisting of polyethylene glycol (PEG) and α- or γ-cyclodextrin (α- or γ-CyD) as pharmaceutical materials for highly concentrated human IgG, we designed the PPRX hydrogels including human IgG and evaluated their pharmaceutical properties. The α- and γ-CyDs formed PPRX hydrogels with PEG (M.W. 20,000) even in the presence of highly concentrated human IgG (>100 mg/mL). According to the results of 1H-NMR, powder X-ray diffraction, and Raman microscopy, the formation of human IgG/CyD PPRX hydrogels was based on physical cross-linking arising from their columnar structures. The release profiles of human IgG from the hydrogels were in accordance with the non-Fickian diffusion model. Importantly, the stabilities of human IgG included into the hydrogels against thermal and shaking stresses were markedly improved. These findings suggest that PEG/CyD PPRX hydrogels are useful to prepare the formulation for highly concentrated human IgG.KEY WORDS: cyclodextrin, human IgG, hydrogel, polypseudorotaxane, stability 相似文献
92.
93.
Nahed Al Laham José R. Mediavilla Liang Chen Nahed Abdelateef Farid Abu Elamreen Christine C. Ginocchio Denis Pierard Karsten Becker Barry N. Kreiswirth 《PloS one》2015,10(3)
Background
Methicillin-resistant Staphylococcus aureus (MRSA) is an important pathogen in both community and healthcare-related settings worldwide. Current knowledge regarding the epidemiology of S. aureus and MRSA in Gaza is based on a single community-based carriage study. Here we describe a cross-sectional analysis of 215 clinical isolates collected from Al-Shifa Hospital in Gaza during 2008 and 2012.Methods
All isolates were characterized by spa typing, SCCmec typing, and detection of genes encoding Panton-Valentine leukocidin (PVL) and toxic shock syndrome toxin (TSST-1). Representative genotypes were also subjected to multilocus sequence typing (MLST). Antibiotic susceptibility testing was performed using VITEK2 and MicroScan.Results
MRSA represented 56.3% of all S. aureus strains, and increased in frequency from 2008 (54.8%) to 2012 (58.4%). Aside from beta-lactams, resistance was observed to tetracycline, erythromycin, clindamycin, gentamicin, and fluoroquinolones. Molecular typing identified 35 spa types representing 17 MLST clonal complexes (CC), with spa 998 (Ridom t223, CC22) and spa 70 (Ridom t044, CC80) being the most prevalent. SCCmec types I, III, IV, V and VI were identified among MRSA isolates, while type II was not detected. PVL genes (lukF/S-PV) were detected in 40.0% of all isolates, while the TSST-1 gene (tst) was detected in 27.4% of all isolates, with surprisingly high frequency within CC22 (70.4%). Both PVL and TSST-1 genes were found in several isolates from 2012.Conclusions
Molecular typing of clinical isolates from Gaza hospitals revealed unusually high prevalence of TSST-1 genes among CC22 MRSA, which is noteworthy given a recent community study describing widespread carriage of a CC22 MRSA clone known as the ‘Gaza strain’. While the latter did not address TSST-1, tst-positive spa 998 (Ridom t223) has been detected in several neighboring countries, and described as endemic in an Italian NICU, suggesting international spread of a ‘Middle Eastern variant’ of pandemic CC22 strain EMRSA-15. 相似文献94.
Seyedeh Sara Shafiei Mehran Solati-Hashjin Ali Samadikuchaksaraei Reza Kalantarinejad Mitra Asadi-Eydivand Noor Azuan Abu Osman 《PloS one》2015,10(8)
In recent years, nanotechnology in merging with biotechnology has been employed in the area of cancer management to overcome the challenges of chemopreventive strategies in order to gain promising results. Since most biological processes occur in nano scale, nanoparticles can act as carriers of certain drugs or agents to deliver it to specific cells or targets. In this study, we intercalated Epigallocatechin-3-Gallate (EGCG), the most abundant polyphenol in green tea, into Ca/Al-NO3 Layered double hydroxide (LDH) nanoparticles, and evaluated its efficacy compared to EGCG alone on PC3 cell line. The EGCG loaded LDH nanohybrids were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy (TEM) and nanosizer analyses. The anticancer activity of the EGCG-loaded LDH was investigated in prostate cancer cell line (PC3) while the release behavior of EGCG from LDH was observed at pH 7.45 and 4.25. Besides enhancing of apoptotic activity of EGCG, the results showed that intercalation of EGCG into LDH can improve the anti- tumor activity of EGCG over 5-fold dose advantages in in-vitro system. Subsequently, the in-vitro release data showed that EGCG-loaded LDH had longer release duration compared to physical mixture, and the mechanism of diffusion through the particle was rate-limiting step. Acidic attack was responsible for faster release of EGCG molecules from LDH at pH of 4.25 compared to pH of 7.4. The results showed that Ca/Al-LDH nanoparticles could be considered as an effective inorganic host matrix for the delivery of EGCG to PC3 cells with controlled release properties. 相似文献
95.
Nigar Nargis Mary E. Thompson Geoffrey T. Fong Pete Driezen A. K. M. Ghulam Hussain Ummul H. Ruthbah Anne C. K. Quah Abu S. Abdullah 《PloS one》2015,10(11)
Background
Smoking and passive smoking are collectively the biggest preventable cause of death in Bangladesh, with major public health burden of morbidity, disability, mortality and community costs. The available studies of tobacco use in Bangladesh, however, do not necessarily employ nationally representative samples needed to monitor the problem at a national scale. This paper examines the prevalence and patterns of tobacco use among adults in Bangladesh and the changes over time using large nationally representative comparable surveys.Methods
Using data from two enumerations of the International Tobacco Control (ITC) Bangladesh Project conducted in 2009 and 2012, prevalence estimates are obtained for all tobacco products by socio-economic determinants and sample types of over 90,000 individuals drawn from over 30,000 households. Household level sample weights are used to obtain nationally representative prevalence estimates and standard errors. Statistical tests of difference in the estimates between two time periods are based on a logistic regression model that accounts for the complex sampling design. Using a multinomial logit model, the time trend in tobacco use status is identified to capture the effects of macro level determinants including changes in tobacco control policies.Results
Between 2009 and 2012, overall tobacco use went down from 42.4% to 36.3%. The decline is more pronounced with respect to smokeless tobacco use than smoking. The prevalence of exclusive cigarette smoking went up from 7.2% to 10.6%; exclusive bidi smoking remained stable at around 2%; while smoking both cigarette and bidi went down from 4.6% to 1.8%; exclusive smokeless tobacco use went down from 20.2% to 16.9%; and both smokeless tobacco use and smoking went down from 8.4% to 5.1%. In general, the prevalence of tobacco use is higher among men, increases from younger to older age groups, and is higher among poorer people. Smoking prevalence is the highest among the slum population, followed by the tribal population, the national population and the border area population, suggesting greater burden of tobacco use among the disadvantaged groups.Conclusions
The overall decline in tobacco use can be viewed as a structural shift in the tobacco market in Bangladesh from low value products such as bidi and smokeless tobacco to high value cigarettes, which is expected with the growth in income and purchasing power of the general population. Despite the reduction in overall tobacco use, the male smoking prevalence in Bangladesh is still high at 37%. The world average of daily smoking among men is 31.1%. The Tobacco Control Act 2005 and the Amendment have yet to make a significant impact in curbing tobacco usage in Bangladesh. The findings in this paper further suggest that the tobacco control policies in Bangladesh need to include targeted interventions to restrain the use of particular types of tobacco products among specific demographic and socio-economic groups of the population, such as smoked tobacco among men, smokeless tobacco among women, and both smoked and smokeless tobacco among those living in rural areas, those in low socio-economic status and those belonging to the tribal and the slum population. 相似文献96.
Objectives
Recent evidence suggests that suicidal ideation is increased among university students, it is essential to increase our knowledge concerning the etiology of suicidal ideation among university students. This study was conducted to examine the relationships between problem-solving skills appraisal, hardiness, and suicidal ideation among university students. In addition, this study was conducted to examine problem-solving skills appraisal (including the three components of problem-solving confidence, approach-avoidance style, and personal control of emotion) as a potential mediator between hardiness and suicidal ideation.Methods
The participants consisted of 500 undergraduate students from Malaysian public universities.Results
Structural Equation Modelling (SEM) estimated that undergraduate students with lower hardiness, poor problem-solving confidence, external personal control of emotion, and avoiding style was associated with higher suicidal ideation. Problem-solving skills appraisal (including the three components of problem-solving confidence, approach-avoidance style, and personal control of emotion) partially mediated the relationship between hardiness and suicidal ideation.Conclusion
These findings underline the importance of studying mediating processes that explain how hardiness affects suicidal ideation. 相似文献97.
98.
Mostafa A. Yehia Tarek S. El-Ammawi Khairia M. Al-Mazidi Mahmoud A. Abu El-Ela Hejab S. Al-Ajmi 《Mycopathologia》2010,169(4):241-246
Background
Fungal infections constitute a major health problem all over the world. Signs and symptoms induced by various dermatophytic infections are difficult to distinguish clinically from each other. So, characterization by in vitro culture is required for appropriate diagnosis and treatment as well as to study the epidemiological characteristics in a region. 相似文献99.
Nina Klee Pui Ee Wong Beatriz Baragaña Farah El Mazouni Margaret A. Phillips Michael P. Barrett Ian H. Gilbert 《Bioorganic & medicinal chemistry letters》2010,20(15):4364-4366
Trypanosoma brucei, the parasite that causes human African trypanosomiasis, is auxotrophic for purines and has specialist nucleoside transporters to import these metabolites. In particular, the P2 aminopurine transporter can also selectively accumulate melamine derivatives. In this Letter, we report the coupling of the melamine moiety to 2-hydroxy APA, a potent ornithine decarboxylase inhibitor, with the aim of selectively delivering this compound to the parasite. The best compound described here shows an increased in vitro trypanocidal activity compared with the parent. 相似文献
100.
A. E. Abu Khamidakh J. V. Demchuk P. P. Zak M. Lindström M. A. Ostrovsky 《Moscow University Biological Sciences Bulletin》2010,65(2):51-55
Microspectrophotometric measurements of screening granules in Mysis relicta eyes showed that most of the granules have xanthommatin spectra (7nmax 455 nm) with selective absorption of blue light. We calculated spectral sensitivity of M.relicta eyes using screening granules absorption spectra and visual pigment absorption spectra. According to our computations the
calculated spectral sensitivity curve appears to be in a good correspondence with the real spectral sensitivity. 相似文献