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991.
Pangkhi Medhi Ololade Olatunji Atul Nayak Chandra Teja Uppuluri Richard T. Olsson Buchi N. Nalluri Diganta B. Das 《AAPS PharmSciTech》2017,18(5):1488-1494
Microneedle (MN) technology has emerged as an effective drug delivery system, and it has tremendous potential as a patient friendly substitute for conventional methods for transdermal drug delivery (TDD). In this paper, we report on the preparation of lidocaine-loaded biodegradable microneedles, which are manufactured from fish scale-derived collagen. Lidocaine, a common tissue numbing anaesthetic, is loaded in these microneedles with an aim of delivering the drug with controlled skin permeation. Evaluation of lidocaine permeation in porcine skin has been successfully performed using Franz diffusion cell (FDC) which has shown that the drug permeation rate increases from 2.5 to 7.5% w/w after 36 h and pseudo steady state profile is observed from 5.0 to 10.0% w/w lidocaine-loaded microneedle. Swelling experiments have suggested that the microneedles have negligible swellability which implies that the patch would stick to the tissue when inserted. The experiments on MN dissolution have depicted that the lidocaine loaded in the patch is lower than the theoretical loading, which is expected as there can be losses of the drug during initial process manufacture. 相似文献
992.
Biodiesel was produced using waste coffee grounds (WCGs) via a two-step process comprising lipid extraction and subsequent transesterification steps. Each step was statistically analyzed, and optimum conditions for each step were suggested. WCGs were found to have 16.4% lipid content with 1.9% free fatty acid (FFA) content. The liquid-solid ratio (LSR) significantly influenced lipid extraction from WCGs, while extraction time and temperature did not; 92.7% of lipid extraction efficiency was achieved at 13.7 mL-hexane/g-WCGs, 30 min of extraction time, and 25°C. Owing to the relatively low FFA content, an alkaline catalyst (NaOH) reaction was used that requires less amount of catalyst, methanol, and shorter reaction time compared to an acid catalyst reaction. Reaction time and temperature were the major factors affecting biodiesel conversion, and 94.0% of biodiesel conversion was obtained at optimum conditions for transesterification: 0.5% catalyst, 1.5 mL-methanol/g-lipid, 45°C, and 9 h of reaction time. With the use of statistical analysis tools, high lipid extraction efficiency and biodiesel conversion were achieved at relatively mild conditions, which would reduce biodiesel production cost substantially. 相似文献
993.
994.
Cuneyt Evren Gokhan Umut Bilge Evren 《Attention deficit and hyperactivity disorders》2017,9(4):231-238
The aim of the present study was to evaluate relationship of self-mutilative behaviour (SMB) with the severity of childhood trauma and adult attention-deficit/hyperactivity disorder (ADHD) symptoms in a sample of inpatients with alcohol use disorder (AUD). Participants included 188 inpatients with AUD. Participants were evaluated with the Self-mutilative Behaviour Questionnaire, the Childhood Trauma Questionnaire (CTQ-28) and the Adult ADD/ADHD DSM-IV Based Diagnostic Screening and Rating Scale (Adult ADHD Scale). Among inpatients with AUD those who have a history of SMB constituted the SMB group (n = 57, 30.3%), and those without a history of SMB constituted the group without SMB (n = 131, 69.7%). Risk of high ADHD risk was 2.5 times higher among those with SMB. Adult ADHD Scale and CTQ-28 scores were also higher in the group with SMB. In the first backward logistic regression model, the severity of ADHD symptoms predicted the presence of SMB, together with the severity of childhood trauma, whereas in the second model, physical neglect and inattentive (IN) dimension of ADHD predicted the presence of SMB. These findings suggest that the higher severity of physical neglect and adult IN dimension of ADHD may be related to SMB among inpatients with AUD. 相似文献
995.
996.
Zhitao Xiao Xinpeng Zhang Lei Geng Fang Zhang Jun Wu Jun Tong Philip O. Ogunbona Chunyan Shan 《Biomedical engineering online》2017,16(1):122
Background
Non-proliferative diabetic retinopathy is the early stage of diabetic retinopathy. Automatic detection of non-proliferative diabetic retinopathy is significant for clinical diagnosis, early screening and course progression of patients.Methods
This paper introduces the design and implementation of an automatic system for screening non-proliferative diabetic retinopathy based on color fundus images. Firstly, the fundus structures, including blood vessels, optic disc and macula, are extracted and located, respectively. In particular, a new optic disc localization method using parabolic fitting is proposed based on the physiological structure characteristics of optic disc and blood vessels. Then, early lesions, such as microaneurysms, hemorrhages and hard exudates, are detected based on their respective characteristics. An equivalent optical model simulating human eyes is designed based on the anatomical structure of retina. Main structures and early lesions are reconstructed in the 3D space for better visualization. Finally, the severity of each image is evaluated based on the international criteria of diabetic retinopathy.Results
The system has been tested on public databases and images from hospitals. Experimental results demonstrate that the proposed system achieves high accuracy for main structures and early lesions detection. The results of severity classification for non-proliferative diabetic retinopathy are also accurate and suitable.Conclusions
Our system can assist ophthalmologists for clinical diagnosis, automatic screening and course progression of patients.997.
Emmanuel Olorunleke Adewuyi Yun Zhao Vishnu Khanal Asa Auta Lydia Babatunde Bulndi 《International breastfeeding journal》2017,12(1):51
Background
This study investigates and compares the rates and factors associated with early initiation of breastfeeding (EIBF) within one hour of birth in rural and urban Nigeria.Methods
Data from the 2013 Nigeria Demographic and Health Survey (NDHS) were analyzed. The rates of EIBF were reported using frequency tabulation. Associated factors were examined using Chi-Square test and further assessed on multivariable logistic regression analysis.Results
The rates of EIBF were 30.8% (95% confidence interval [CI] 29.0, 32.6) and 41.9% (95% CI 39.6, 44.3) in rural and urban residences, respectively (p?<?0.001). The North-Central region had the highest EIBF rates both in rural (43.5%) and urban (63.5%) residences. Greater odds of EIBF in rural residence were significantly associated with higher birth order (Adjusted Odds Ratio [AOR] 1.29, 95% CI 1.10, 1.60), large birth size (AOR 1.33, 95% CI 1.10, 1.60), and health facility delivery (AOR 1.46, 95% CI 1.23, 1.72). Rural mothers in the rich wealth index, not working and whose husbands obtained at least a secondary school education had significantly higher odds of early initiation of breastfeeding. Regardless of residence, greater odds of EIBF were significantly associated with non-cesarean delivery (Rural AOR 3.50, 95% CI 1.84, 6.62; Urban AOR 2.48, 95% CI 1.60, 3.80) and living in North-Central (Rural AOR 1.84, 95% CI 1.34, 2.52; Urban AOR 4.40, 95% CI 3.15, 6.15) region. Also, higher odds of EIBF were significantly associated with living in North-East (Rural AOR 1.48, 95% CI 1.05, 2.08; Urban AOR 3.50, 95% CI 2.55, 4.83), South-South (Rural AOR 1.51, 95% CI 1.11, 2.10; Urban AOR 2.84, 95% CI 2.03, 3.97) and North-West (Urban residence only AOR 2.08, 95% CI 1.54, 2.80) regions.Conclusions
Rural-urban differences in the rates and factors associated with EIBF exist in Nigeria with rural residence having significantly lower rates. Intervention efforts which address the risk factors identified in this study may contribute to improved EIBF rates. Efforts need to prioritize rural mothers generally, (particularly, those in rural North-West region) as well as mothers in urban South-West region of Nigeria.998.
Meghan E. Hall Nima Khadem Mohtaram Stephanie M. Willerth 《Journal of biological engineering》2017,11(1):38
Background
Human induced pluripotent stem cells (hiPSCs) can form any tissue found in the body, making them attractive for regenerative medicine applications. Seeding hiPSC aggregates into biomaterial scaffolds can control their differentiation into specific tissue types. Here we develop and analyze a mathematical model of hiPSC aggregate behavior when seeded on melt electrospun scaffolds with defined topography.Results
We used ordinary differential equations to model the different cellular populations (stem, progenitor, differentiated) present in our scaffolds based on experimental results and published literature. Our model successfully captures qualitative features of the cellular dynamics observed experimentally. We determined the optimal parameter sets to maximize specific cellular populations experimentally, showing that a physiologic oxygen level (~?5%) increases the number of neural progenitors and differentiated neurons compared to atmospheric oxygen levels (~?21%) and a scaffold porosity of ~?63% maximizes aggregate size.Conclusions
Our mathematical model determined the key factors controlling hiPSC behavior on melt electrospun scaffolds, enabling optimization of experimental parameters.999.
We aim to unravel the biogeographic structuring of western Palaearctic longhorn beetles with focus on the location of different refugia, barriers to dispersal and postglacial range expansions with their particular filters. The interaction of different ecological features with these structures is analysed. The western Palaearctic was divided into 95 geographic entities. We produced presence-only matrices for all 955 Cerambycoidea species autochthonous to this area and derived species richness distributions and extracted faunal regions and faunal elements by cluster analyses and principal component analyses. Similar analyses were performed for sub-families and ecological groups. Longhorn beetles show a strong biogeographic structuring in the western Palaearctic. Species numbers strongly decrease to the north and west. Less mobile species and root feeders mostly contribute to the fauna of the Mediterranean region, whilst mobile species are more widespread. Feeders on broad-leaved trees dominate in western Europe, whilst feeders on coniferous trees are most important in northern Europe. Our results support multiple refugia in the Mediterranean region and underline the importance of Provence, Crimea and Crete as such refugia. Crete even might be an area of old endemism. The Atlanto- and the Ponto-Mediterranean regions are more strongly structured than assumed in classical biogeography. Mediterranean assemblages are mostly composed of non-flying species, root feeders and species with small distributions not found outside their glacial refugia. Tree feeders left their glacial retreats with their host plants. These range dynamics result in biogeographic structures with several dispersal barriers and filters composed of mountains, sea straits and climatic conditions. 相似文献
1000.
Mahdi Ghanbari Hadi Shahraki Wolfgang Kneifel Konrad J. Domig 《Symbiosis (Philadelphia, Pa.)》2017,72(3):183-193
This study addresses the biodiversity profile of bacterial community in the intestinal lumen and mucosa of snow trout fish by applying 16S rRNA gene 454-pyrosequencing. A total of 209,106 sequences with average length 689 (±53) were filtered, denoised, trimmed, and then sorted into OTUs based on 97 % sequence similarity using the USEARCH software pipeline. Bacteria representing 10 phyla were found in the samples investigated. Fimicutes ribotypes were present in intestinal-mucosa and lumen in all fish and often dominated the libraries (average 43 and 38 %, respectively). Proteobacteria were also prevalent, but at a lower relative abundance, at 22 and 29 % in mucosa and lumen, respectively. The autochthonous microbiota was dominated by sequences belonging to the Bacilli (mean sequence abundance 24 %), in particular the Lactobacillaceae, with Lactobacillus and Pediococcous being the most abundant genera. Fewer Bacilli (mean sequence abundance 22 %) and Actinobacteria (2 %) were present in the lumen, and allochthonous communities consisted of a more even split among the bacterial classes, with increases in sequences assigned to members of the γ-Proteobacteria (16 %) and Fusobacteriia (8 %). The principal bacterial genera recorded in the lumen belonged to the lactic acid bacteria group, Cetobacterium, Clostridium and Synechococcus. Results obtained suggest that the lumen and mucosal layer of the snow trout intestine may host different microbial communities. Moreover, both regions harbour a diverse microbiome with a greater microbial diversity in the intestinal mucus compared with the luminal communities of the fish. Many of these microbes might be of high physiological relevance for the fish and may play key roles in the functioning of its gut. 相似文献