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291.
Janet K. Kern Carolyn R. Garver Jyutika A. Mehta Patricia A. Hannan Liz E. Bakken Aileen M. Vidaud Judie Abraham Yahya Daoud 《The Yale journal of biology and medicine》2013,86(2):157-167
The purpose of the study was to explore a low-cost intervention that targets an
increasingly common developmental disorder. The study was a blinded, exploratory
evaluation of the PlayWisely program on autism symptoms and essential learning
foundation skills (attention, recognition, and memory skills) in children with a
diagnosis of autism, autism spectrum disorder (ASD), pervasive developmental
disorder – not otherwise specified (PDD-NOS), and Asperger syndrome (AS).
Eighteen children, 1 to 10 years of age, were evaluated using the Childhood
Autism Rating Scale, Second Edition (CARS2); the PlayWisely Interactive Test of
Attention, Recognition, and Memory Skills; Autism Treatment Evaluation Checklist
(ATEC), and the Modified Checklist for Autism in Toddlers (M-CHAT). There were
significant treatment effects for the PlayWisely measure on the Yellow Sets that
examine recognition; Purple Sets that examine brain region agility and early
memory skills; Blue Sets that examine phonemic awareness and recognition; and
for the Total Sets, with a similar trend toward improvement in the Green Sets
that examine perception and Red Sets that examine attention. No other measures
reached statistical significance. The results suggest that PlayWisely can
improve recognition, brain region agility, phonemic awareness, letter
recognition, and early memory skills in ASD. It was observed by the parents,
coaches, and study investigators that the children who were less than 3 years of
age showed improvements in autism symptoms; however, the group was too small to
reach statistical significance. Future studies are needed to see if this
intervention can mitigate autism symptoms in very young children with ASD. 相似文献
292.
Oluwatoyin A. Adeleke Yahya E. Choonara Pradeep Kumar Lisa C. du Toit Lomas K. Tomar Charu Tyagi Viness Pillay 《AAPS PharmSciTech》2013,14(4):1349-1359
Drug release from hydrophilic matrices is regulated mainly by polymeric erosion, disentanglement, dissolution, swelling front movement, drug dissolution and diffusion through the polymeric matrix. These processes depend upon the interaction between the dissolution media, polymeric matrix and drug molecules, which can be significantly influenced by formulation variables and excipients. This study utilized mathematical parameters to evaluate the impacts of selected formulation variables and various excipients on the release performance of hydrophilic polyamide 6,10 (PA 6,10) monolithic matrix. Amitriptyline HCl and theophylline were employed as the high and low solubility model drugs, respectively. The incorporation of different excipient concentrations and changes in formulation components influenced the drug release dynamics as evidenced by computed mathematical quantities (t x%, MDT x%, f 1, f 2, k 1, k 2, and К F). The effects of excipients on drug release from the PA 6,10 monolithic matrix was further elucidated using static lattice atomistic simulations wherein the component energy refinements corroborates the in vitro and in silico experimental data. Consequently, the feasibility of modulating release kinetics of drug molecules from the novel PA 6,10 monolithic matrix was well suggested. 相似文献
293.
Yahya M. Nor 《Chemical Speciation and Bioavailability》2013,25(2):85-91
AbstractUptake of metals by whole Eichhornia crassipes plants and excised roots was studied using a bioassay system. Results indicate that in time-series bioassay at concentration of 10 mg L?1 of either Zn or Cu, rapid uptake by whole plants occurred during the first 4 h, but subsequently levelled off after 48 h. A greater proportion of metals absorbed remain in the root system rather than being translocated to other parts of plant. When treated with different combinations of both Cu and Zn, some synergistic effect of metals appeared to have occurred as indicated by enhanced uptake when bioassays involved combination of metals. Absorption kinetics of monovalent K+ by excised Eichhornia roots after a 24-h treatment, indicated an initial linear trend over the range of 1–10 mg K L?1, but subsequently levelled off at 15 mg K L?1 concentration with Vmax of 7.5 × 10–6 M K g?1 dry tissue h?1 and Km of 1.1 × 10?3 M K. Potentiometric titrations revealed existence of pH-dependent charge densities on root system which have variable affinities for cations and helps explain the ability of Eichhornia roots to absorb and accumulate large amounts of metal ions especially at high pH of media. 相似文献
294.
Negahban S Daneshbod Y Atefi S Daneshbod K Sadjjadi SM Hosseini SV Bedayat GR Abidi H 《Acta cytologica》2007,51(4):567-570
BACKGROUND: Dirofilariasis due to Dirofilaria repens with viable microfilariae outside the worm have not been reported before. CASE: A 40-year-old truck driver from rural Shiraz, Iran, had a firm mass, 2.5 x 2.5 cm, at the dorsolateral aspect of the right forearm. Fine needle aspiration (FNA) was performed on 2 occasions. Several microfilariae with blunt heads, pointed posterior ends and empty caudal spaces resembling microfilariae of Wuchereria bancrofti but longer were seen. Since Iran is a nonendemic area for lymphatic filariae and the patient had a history of contact with a dog, with the impression of dirofilariasis, the mass was excised, and the presence of adult worms in tissue sections confirmed the diagnosis. CONCLUSION: This case ofsubcutaneous dirofilariasis was diagnosed by detecting microfilariae in FNA smears and was confirmed on histopathology. 相似文献
295.
Seyed Yahya Anvar Jeroen Frank Arjan Pol Arnoud Schmitz Ken Kraaijeveld Johan T den Dunnen Huub JM Op den Camp 《BMC genomics》2014,15(1)
Background
Aerobic methanotrophs can grow in hostile volcanic environments and use methane as their sole source of energy. The discovery of three verrucomicrobial Methylacidiphilum strains has revealed diverse metabolic pathways used by these methanotrophs, including mechanisms through which methane is oxidized. The basis of a complete understanding of these processes and of how these bacteria evolved and are able to thrive in such extreme environments partially resides in the complete characterization of their genome and its architecture.Results
In this study, we present the complete genome sequence of Methylacidiphilum fumariolicum SolV, obtained using Pacific Biosciences single-molecule real-time (SMRT) sequencing technology. The genome assembles to a single 2.5 Mbp chromosome with an average GC content of 41.5%. The genome contains 2,741 annotated genes and 314 functional subsystems including all key metabolic pathways that are associated with Methylacidiphilum strains, including the CBB pathway for CO2 fixation. However, it does not encode the serine cycle and ribulose monophosphate pathways for carbon fixation. Phylogenetic analysis of the particulate methane mono-oxygenase operon separates the Methylacidiphilum strains from other verrucomicrobial methanotrophs. RNA-Seq analysis of cell cultures growing in three different conditions revealed the deregulation of two out of three pmoCAB operons. In addition, genes involved in nitrogen fixation were upregulated in cell cultures growing in nitrogen fixing conditions, indicating the presence of active nitrogenase. Characterization of the global methylation state of M. fumariolicum SolV revealed methylation of adenines and cytosines mainly in the coding regions of the genome. Methylation of adenines was predominantly associated with 5′-m6ACN4GT-3′ and 5′-CCm6AN5CTC-3′ methyltransferase recognition motifs whereas methylated cytosines were not associated with any specific motif.Conclusions
Our findings provide novel insights into the global methylation state of verrucomicrobial methanotroph M. fumariolicum SolV. However, partial conservation of methyltransferases between M. fumariolicum SolV and M. infernorum V4 indicates potential differences in the global methylation state of Methylacidiphilum strains. Unravelling the M. fumariolicum SolV genome and its epigenetic regulation allow for robust characterization of biological processes that are involved in oxidizing methane. In turn, they offer a better understanding of the evolution, the underlying physiological and ecological properties of SolV and other Methylacidiphilum strains.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-914) contains supplementary material, which is available to authorized users. 相似文献296.
Famida G. Hoosain Yahya E. Choonara Pradeep Kumar Lomas K. Tomar Charu Tyagi Lisa C. du Toit Viness Pillay 《AAPS PharmSciTech》2014,15(5):1292-1306
The current study involved the development of a novel sustained release crosslinked semi-IPN xerogel matrix tablet prepared by chemical crosslinking of poly(ethylene) oxide (PEO) and gellan gum (GG) employing epichlorohydrin (EPI) as crosslinker. A Box–Behnken design was employed for the statistical optimization of the matrix system to ascertain the ideal combination of native polymeric and crosslinking agents. Characterization studies were performed by employing standard polymer characterization techniques such as Fourier transform infrared spectrometry, differential scanning calorimetry, and scanning electron microscopy. Formulated matrix tablets displayed zero-order release kinetics, extending over 24 h. The mechanism of drug release was primarily by swelling and surface erosion. Crosslinked semi-IPN xerogel matrix tablets were compared to non-crosslinked polymer blends; results from the study conducted showed that the physiochemical properties of the PEO and GG were sufficiently modified to allow for sustained release of sulpiride with a 100% drug release at 24 h in a controlled manner as compared to non-crosslinked formulations which displayed further release beyond the test period. Crosslinked formulations displayed water uptake between 450 and 500% indicating a controlled rate of swelling and erosion allowing for sustained release. Surface morphology of the crosslinked system depicted a porous structure formed by interpenetrating networks of polymers, allowing for a greater degree of controlled penetration into the system affording it the ability to sustain drug release. Therefore, conclusively, based on the study performed, crosslinked PEO-GG allows for the sustained release of sulpiride from a hydrophilic semi-IPN xerogel matrix system.KEY WORDS: epichlorohydrin, matrix tablet, semi-interpenetrating polymer network, sustained release, sulpiride 相似文献
297.
Güven Cetin Tuba Ozkan Seda Turgut M. Ali Cikrikcioglu M. Cem Ar Mesut Ayer Ayhan Unlu Sevda Rabia Celik Yahya Sekin Cumali Karatoprak 《Molecular biology reports》2014,41(10):6737-6742
Essential thrombocythemia (ET) is an entity of classic Philadelphia chromosome-negative myeloproliferative neoplasms (MPNs), characterized by thrombocytosis with megakaryocytic hyperplasia and thrombocytes are increased with abnormal functions. Discovery of the protein tyrosine kinase JAK2 V617F allele contributed to better understanding of the pathogenetic mechanisms of MPNs. Acquired single point mutation in the JAK2 V617F was determined approximately 50–60 % of patients with ET. In this study we aimed to investigate the relationship between JAK2 V617F gene mutation, hematologic, biochemical markers and the complications in the ET patients. A total of 268 patients diagnosed with ET and 219 of those studied for JAK2 gene mutation were followed at the hematology clinics of three major hospitals between 2008 and 2013 were screened retrospectively. Laboratory, clinical and hematologic parameters were compared for JAK2 V617F positive and JAK2 V617F negative patients with ET. 102 (46 %) patients were positive with the JAK2 V617F mutation. The complications were observed in 61 (28 %) patients and 38 (62 %) of them had JAK2 V617F mutation. The levels of white blood cells, neutrophil, basophil, red blood cells, hemoglobin, hematocrit, mean platelet volume, thrombocytes, eosinophil; urea, creatinine were significantly different in patients with the JAK2 V617F mutation (P < 0.05). Presence of the JAK2 V617F mutation supports the diagnosis of ET. It would be useful to investigate the JAK2 V617F mutation and the hematologic and biochemical markers at diagnosis with respect to consider the risk of developing complications and to take the precautions against these complications. 相似文献
298.
This cross sectional survey was conducted to determine the support in making Penang UNESCO World Heritage Site (GTWHS) smoke free and to determine the influence of tolerance towards smoking on this support. This is the first phase in making Penang, Malaysia a smoke free state. A multistage sampling process was done to select a sample of respondents to represent the population of GTWHS. Attitude towards smoking was assessed using tolerance as a proxy. A total of 3,268 members of the community participated in the survey. A big majority (n = 2969; 90.9%) of the respondents supported the initiative. Support was lowest among the owners and residents/tenants, higher age groups, the Chinese, men, respondents who had poor knowledge of the places gazetted as smoke free, and respondents with poor knowledge of the health effects on smokers and on passive smokers. The odds (both adjusted and unadjusted) of not supporting the initiative was high among those tolerant to smoking in public areas. Tolerance towards smoking was associated with 80.3% risk of non-support in the respondents who were tolerant to smoking and a 57.2% risk in the population. Health promotion and education concerning the harm of tobacco smoke in Malaysia, which has mainly targeted smokers, must change. Health education concerning the risks of second hand smoke must also be given to non-smokers and efforts should be made to denormalize smoking. 相似文献
299.
Effects of Echis pyramidum Snake Venom on Hepatic and Renal Antioxidant Enzymes and Lipid Peroxidation in Rats 下载免费PDF全文
Abdulrahman K. Al Asmari Haseeb A. Khan Rajamohammed A. Manthiri Khalid M. Al Yahya Kitab E. Al Otaibi 《Journal of biochemical and molecular toxicology》2014,28(9):407-412
The effects of Echis pyramidum venom (EPV) (0.25, 0.50, and 1.00 mg/kg) on activities of superoxide dismutase (SOD) and catalase (CAT) and levels of thiobarbituric acid reactive substances (TBARS) and total thiols (T‐SH) in liver and kidneys of rats were investigated. EPV significantly and dose dependently decreased the activities of SOD and CAT in livers. Although the kidney SOD and CAT activities were not affected by low and medium doses of EPV, the high dose significantly reduced the activities of these enzymes. Liver and kidney TBARS levels were not affected by the low and medium doses of EPV, whereas the high dose significantly increased the TBARS after 6 h postdosing. There was a significant depletion of T‐SH in liver and kidneys of rats exposed to a high dose of EPV. The acute phase oxidative stress due to an EPV injection points toward the importance of an early antioxidant therapy for the management of snake bites. 相似文献
300.
Yeoh Seak Hui A. A. Amirul Ahmad R. M. Yahya M. N. M. Azizan 《World journal of microbiology & biotechnology》2010,26(1):79-84
Aspergillus terreus, isolated from rotting bagasse, showed comparable cellulolytic activities when grown either in the free or immobilized states
with cellulose as the sole carbon source. The cultural and nutritional requirements for maximum cellulase production by the
organism either in the free or immobilized states were similar, except an increase in the temperature optimum from 30 to 40°C,
occurred upon immobilization. In the free state, the maximum filter paper hydrolase, carboxymethylcellulase and β-glucosidase
activities produced were 2.1, 13.6, and 3.2 U/ml, respectively, while in the immobilized state, the levels were 1.8, 12.0,
and 2.4 U/ml. Production of cellulolytic enzymes by immobilized cells was influenced by the surface area of the support material.
In addition, cells in the immobilized state sustained enzyme production for a much longer period with a 4.5-fold increase
in productivity during repeated batch when compared to free cells. 相似文献