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981.
Bond J Scott S Hampshire DJ Springell K Corry P Abramowicz MJ Mochida GH Hennekam RC Maher ER Fryns JP Alswaid A Jafri H Rashid Y Mubaidin A Walsh CA Roberts E Woods CG 《American journal of human genetics》2003,73(5):1170-1177
Mutations in the ASPM gene at the MCPH5 locus are expected to be the most common cause of human autosomal recessive primary microcephaly (MCPH), a condition in which there is a failure of normal fetal brain development, resulting in congenital microcephaly and mental retardation. We have performed the first comprehensive mutation screen of the 10.4-kb ASPM gene, identifying all 19 mutations in a cohort of 23 consanguineous families. Mutations occurred throughout the ASPM gene and were all predicted to be protein truncating. Phenotypic variation in the 51 affected individuals occurred in the degree of microcephaly (5-11 SDs below normal) and of mental retardation (mild to severe) but appeared independent of mutation position. 相似文献
982.
Kabilan S Blyth J Lee MC Marshall AJ Hussain A Yang XP Lowe CR 《Journal of molecular recognition : JMR》2004,17(3):162-166
Holographic sensors for monitoring glucose were fabricated from hydrogel films containing chemical ligands based on phenylboronic acid. The films were transformed into reflection holograms using a diffusion method coupled with exposure to laser light. The diffraction wavelength of the holograms was used to monitor the swelling of the hydrogel film in the presence of glucose. Fully reversible changes in diffraction wavelength were demonstrated, highlighting the potential for using these holograms as glucose sensors. 相似文献
983.
Ashraf MZ Singh M Hussain ME Prasad AK Fahim M 《Indian journal of experimental biology》2001,39(4):329-333
The contractility of airway smooth muscle (ASM) plays an important role in pathophysiology of several bronchial disorders. Increased contraction of ASM during asthma and respiratory viral infection has been attributed to the release of mediators acting through different receptors. In the present study, influence of influenza type A virus (H1N1) infection has been examined on ASM responsiveness to various bronchoactive agents e.g. adenosine, histamine, 5-hydroxytryptamine (5-HT) and isoproterenol in an organ bath set up for isolated tissue preparation. The contractile effect of adenosine, histamine and 5-HT was enhanced, however, relaxant response of isoproterenol was attenuated with the duration following viral exposure. The most prominent response was observed 48 to 72 hr after infection and tissues from multiple exposure to virus infected animals showed the maximum contractile response. Results demonstrated the deleterious effect of viral infection on ASM function and the findings will be helpful in understanding the mechanism of influenza virus induced bronchoconstriction. 相似文献
984.
Al-Haddawi MH Jasni S Son R Mutalib AR Bahaman AR Zamri-Saad M Sheikh-Omar AR 《The Journal of General and Applied Microbiology》1999,45(6):269-275
Forty isolates of Pasteurella multocida from healthy (17 isolates) and diseased (23 isolates) rabbits were assayed for the presence of plasmids in seeking to determine whether any correlation exists between the presence of plasmids and health status, sensitivity to antimicrobial agents, capsular and somatic type, and the anatomic site of isolation. Six isolates were found harboring plasmids. A similar ladder pattern ranging from 18 to 3 megadalton (Mda) were found in three isolates recovered from diseased rabbits. One band of molecular weight 6.6 Mda was shared by four of five (4/5) isolates from the diseased rabbits. No correlation was found between the presence of the common plasmids and serotype, resistance to antimicrobial agents, and anatomic sites from which the bacteria were cultured. Random amplification polymorphic DNA was applied to subtype all the isolates of P. multocida. Two single primers were tested for their abilities to generate individual fingerprints by using PCR. Primer 1 grouped the isolates into 7 profiles, and primer 2 grouped them into 15. Random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) results show the presence of a wide heterogeneity within P. multocida isolates. Therefore RAPD-PCR is an efficient technique to detect the DNA polymorphism and could be used to discriminate P. multocida of rabbit isolates together with serologic typing. 相似文献
985.
Ahmad VU Abbasi MA Hussain H Akhtar MN Farooq U Fatima N Choudhary MI 《Phytochemistry》2003,63(2):217-220
One new phenolic glycoside named benzoylsalireposide (1) along with one known phenolic glycoside named salireposide (2) have been isolated from Symplocos racemosa. Four other known compounds i.e. beta-amyrin (3), oleonolic acid (4), beta-sitosterol (5) and beta-sitosterol glycoside (6) were also isolated from this plant. The structure elucidation of the isolated compounds was based primarily on 1D- and 2D-NMR analysis, including COSY, HMQC, and HMBC correlations. The compound 1 and 2 showed inhibitory activity against snake venom phosphodiesterase I. 相似文献
986.
987.
Determination of mifepristone levels in wild canid serum using liquid chromatography 总被引:3,自引:0,他引:3
Stith C Delwar Hussain M 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2003,794(1):9-15
An HPLC method was developed to determine levels of mifepristone, in coyote (Canis latrans) serum where mifepristone will be used as an oral contragestive agent for nonlethal predator control. Serum samples were extracted using C(18) solid-phase extraction cartridges. A synthetic analog of mifepristone, RTI-3021-003, was used as the internal standard. Separation of the compounds was achieved by using a C(18) (150 x 4.6 mm) column. The mobile phase was 55% acetonitrile in water running at 1.0 ml/min with UV detection at 305 nm. The assay was linear in the range of 10 to 1000 ng/ml. Inter-day accuracies for 10, 200 and 1000 ng/ml were 95.9, 99.4 and 104.7%, respectively. Inter-day precisions measured by RSD were 19.8, 9.7 and 4.5%. Intra-day accuracies were 117, 106.9 and 99.4% for 10, 200 and 1000 ng/ml, respectively. Intra-day RSDs were 19.7, 3.7 and 9.3%, respectively. A simple, sensitive and validated HPLC analytical method was developed to quantitate mifepristone in canine serum. 相似文献
988.
The endocrine pancreas is comprised of beta and alpha cells producing the glucostatic hormones insulin and glucagon, respectively, and arises during development by the differentiation of stem/progenitor cells in the foregut programmed by the beta cell lineage-specific homeodomain protein Idx-1. Brain-4 (Brn-4) is expressed in the pancreatic anlaga of the mouse foregut at e10 in the alpha cells and transactivates glucagon gene expression. We expressed Brn-4 in pancreatic precursors or beta cell lineage in transgenic mice by placing it under either Idx-1 or insulin promoter (rat insulin II promoter) control, respectively. Idx-1 expression occurs at developmental day e8.5, and insulin expression occurs at e9.5, respectively. Misexpression of Brn-4 by the Idx-1 promoter results in ectopic expression of the proglucagon gene in insulin-expressing pancreatic beta cells, whereas misexpression by rat insulin II promoter did not. The early developmental expression of Brn-4 appears to be a dominant regulator of the glucagon expressing alpha cell lineage, even in the context of the beta cell lineage. 相似文献
989.
Rudkowski JC Barreiro E Harfouche R Goldberg P Kishta O D'Orleans-Juste P Labonte J Lesur O Hussain SN 《American journal of physiology. Lung cellular and molecular physiology》2004,286(4):L793-L800
Apoptosis(programmed cell death) is induced in pulmonary cells and contributes to the pathogenesis of acute lung injury in septic humans. Previous studies have shown that nitric oxide (NO) is an important modulator of apoptosis; however, the functional role of NO derived from inducible NO synthase (iNOS) in sepsis-induced pulmonary apoptosis remains unknown. We measured pulmonary apoptosis in a rat model of Escherichia coli lipopolysaccharide (LPS)-induced sepsis in the absence and presence of the selective iNOS inhibitor 1400W. Four groups were studied 24 h after saline (control) or LPS injection in the absence and presence of 1400W pretreatment. Apoptosis was evaluated using DNA fragmentation, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining, and caspase activation. LPS administration significantly augmented pulmonary cell apoptosis and caspase-3 activity in airway and alveolar epithelial cells. Pretreatment with 1400W significantly enhanced LPS-induced pulmonary apoptosis and increased caspase-3 and -7 activation. The antiapoptotic effect of iNOS was confirmed in iNOS-/- mice, which developed a greater degree of pulmonary apoptosis both under control conditions and in response to LPS compared with wild-type mice. By comparison, genetic deletion of the neuronal NOS had no effect on LPS-induced pulmonary apoptosis. We conclude that NO derived from iNOS plays an important protective role against sepsis-induced pulmonary apoptosis. 相似文献
990.
The effect of anhydrous lactose particle size distribution on its performance in the wet granulation process was evaluated.
Three grades of anhydrous lactose were used in the study: “as is” manufacturer grade and 2 particle size fractions obtained
by screening of the 60M lactose. Particle growth behavior of the 3 lactose grades was evaluated in a high shear mixer. Compactibility
and porosity of the resulting granules were also evaluated. A uniaxial compression test on moist agglomerates of the 3 lactose
grades was performed in an attempt to explain the mechanism of particle size effect observed in the high shear mixer. Particle
growth of anhydrous lactose in the high shear mixer was inversely related to the particle size of the starting material. In
addition, granulation manufactured using the grade with the smallest particle size was more porous and demonstrated enhanced
compactibility compared with the other grades. Compacts with similar porosity and low liquid saturation demonstrated brittle
behavior and their breakage strength was inversely related to lactose particle size in the uniaxial compression test, suggesting
that material with smaller particle size may exhibit more pronounced nucleation behavior during wet granulation. On the other
hand, compacts prepared at higher liquid saturation and similar compression force exhibited more plastic behavior and showed
lower yield stress for the grade with smallest particle size. The lower yield stress of compacts prepared with this grade
may indicate a higher coalescence tendency for its granules during wet granulation. 相似文献