Search Results - (Author, Cooperation:S. Sami)

2014-01-15

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Aneuploidy ; Animals ; Cellular Reprogramming/genetics ; Chromosomal Instability/genetics ; Chromosome Deletion ; Chromosome Disorders/genetics/pathology ; Chromosomes, Human, Pair 13/genetics ; Chromosomes, Human, Pair 17/genetics ; Clone Cells/cytology/metabolism ; Fibroblasts/cytology/metabolism ; Humans ; Induced Pluripotent Stem Cells/*cytology/*metabolism ; Karyotype ; Karyotyping ; Male ; Mice ; Models, Genetic ; *Ring Chromosomes ; Uniparental Disomy/genetics

2018-05-09

BMJ Publishing Group

0017-5749

1468-3288

Medicine

Open access, Gut

1478-1913

Blackwell Publishing Journal Backfiles 1879-2005

Theology and Religious Studies

Electronic Resource

1619-7089

Benzodiazepine receptor ; Iodine-123 isopropyl-p-iodoamphetamine ; Iomazenil ; Ischemia ; Autoradiography

Springer Online Journal Archives 1860-2000

Medicine

Abstract Single-photon emission tomography (SPET) imaging in patients with complex partial epilepsy has shown that the seizure focus is characterized by both decreased interictal blood flow and decreased uptake of the benzodiazepine (BZ) receptor tracer iodine-123 iomazenil. The purpose of this study was to examine the confounding effect of decreased flow on iomazenil uptake. The left middle cerebral artery of four rats was occluded, and the animals were simultaneously injected with 25 μCi of iodine-125 iomazenil and 500 μCi of the blood flow tracer [123I]iofetamine (N-isopropyl-p-iodoamphetamine). All rats, including two sham, were sacrificed 1 h after injection, a time when uptake of both agents is nearly maximal. Control experiments showed that arterial occlusion for 1 h did not affect the total number of BZ binding sites. Using a dual autoradiographic technique, the uptake of both [123I]iofetamine and [125I]iomazenil was measured in more than 200 regions showing variable levels of reduced flow and expressed as a percentage of the contralateral homotypic area. The straight line fit of % [125I]iomazenil (y axis) versus % [123I]iofetamine (x axis) in all 200 regions had a slope of 0.74. Insofar as the rat is an accurate model of human subjects with epilepsy, these studies suggest that decreased flow to the epileptogenic focus will linearly exacerbate the decrease in uptake secondary to neuropathologic loss of BZ receptors. Thus, for localization of seizure focus, a single SPET image of [123I]iomazenil in an epileptic patient may have greater sensitivity than a comparable blood flow image, because the former is enhanced by both decreased flow and a loss of BZ receptors.

Electronic Resource

1619-7089

Dopamine transporter ; 2β-Carbomethoxy3β-(4-iodophenyl)tropane ; Carboisopropoxy-3β-(4-iodophenyl)tropane ; Single-photon emission tomography

Springer Online Journal Archives 1860-2000

Medicine

Abstract Single-photon emission tomographic (SPET) imaging with the radiotracer [123I]2β-carbomethoxy-3β-(4-iodophenyl)tropane ([123I]β-CIT) has been reported to be a useful in vivo measure of dopamine (DA) transporters. However, in addition to its high DA transporter affinity,β-CIT also binds with high affinity to serotonin (5-HT) transporters. 2β-Carboisopropoxy-3β-(4-iodophenyl)tropane (IPCIT) has been demonstrated by in vitro studies to have higher selectivity for the DA transporter. We compared [123I]β-CIT and [123I]IPCIT SPET imaging and plasma metabolite analyses in baboons to evaluate the potential advantages of [123I]IPCIT for quantitative in vivo measurements of DA transporter densities. Both tracers had low levels (2% of total plasma123I activity) of lipophilic radiolabeled metabolites at 420 min. [123I]IPCIT had significantly higher binding to plasma proteins. The average percent free (nonprotein bound) [123I]β-CIT and [123I]IPCIT were 52%±7% and 14%±6%, respectively. Region of interest uptake data were normalized by injected dose and body weight. Consistent with the high density of 5-HT transporters in the midbrain and the lower 5-HT transporter affinity of IPCIT, the normalized peak specific midbrain uptake of [123I]β-CIT (1.7±0.5) was higher than that of [123I]IPCIT (0.4±0.2). Consistent with its greater lipophilicity, [123I]IPCIT had higher nonspecific uptake, such that normalized cerebellar uptake of [123I]IPCIT was about twice that of [123I]β-CIT. The ratio of specific to nonspecific uptake in striatum was greater for [123I]β-CIT compared to [123I]IPCIT; however, striatal binding potentials and distribution volumes were not significantly different. In conclusion, [123I]IPCIT demonstrated in vivo a higher DA transporter selectivity and higher level of nonspecific uptake.

Electronic Resource

1573-7330

antisperm antibodies ; sperm ; unexplained infertility ; in vitro fertilization

Springer Online Journal Archives 1860-2000

Medicine

Abstract To clarify further the role of antisperm antibodies in in vitro fertilization, the occurrence of antisperm antibodies on ejaculated sperm and in sera was determined by the immunobead binding assay in 67 couples after an unsuccessful in vitro fertilization cycle. Antisperm antibodies in maternal sera were associated with a failure of oocyte fertilization (P 〈0.02) or with fertilization of only 9–19% of the oocytes (P 〈0.01) in vitro. Antisperm antibodies were detected in sera from 13 of 24 women (54.2%) where no fertilization occurred, 9 of 14 women (64.3%) where less than 20% of the oocytes fertilized, and 3 of 19 women (15.8%) where greater than 40% of the oocytes fertilized. Antisperm antibodies in these sera were mostly IgG and directed against the sperm tail. Antibodies on the surface of ejaculated motile sperm were also associated with a low (9–19%) fertilization rate (P 〈0.01). Sperm-bound antibodies were detected in 2 of 24 men (8.3%) where no fertilization occurred, 5 of 14 men (35.7%) where less than 20% of the oocytes fertilized, and 0 of 19 men where fertilization was greater than 40%. Sperm-bound antibodies were mainly IgA and were tail-directed. Antisperm antibodies in sera of males were not related to the rate of fertilization. Antisperm antibodies were detected in female partners of 21 of 46 couples (45.7%) with unexplained infertility, 2 of 12 women (16.7%) with blocked tubes, 4 of 7 women (57.1%) with endometriosis, and 0 of 2 women with adrenal hyperplasia. There was no relation between the fertilization rate and the maternal age, number of oocytes harvested, or semen quality. We conclude that antisperm antibodies are present in sera from a high percentage of women with unexplained infertility and that antibodies reacting with sperm tails may directly interfere with fertilization in vitro or may be a surrogate marker for another factor that interferes with this event.

Electronic Resource

1573-1987

Springer Online Journal Archives 1860-2000

Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics

Abstract In this paper, an experimental study on the heat transfer characteristics of two phase flow condensation of pure refrigerants such as R-12 and R-22 as well as non-azeotropic refrigerant mixtures R-22/R-114 and R-22/R-152a on horizontal enhanced surface tubing is presented. The enhanced surface tubing data showed a significant enhancement of the heat transfer compared to an equivalent smooth tube depending on the mixture components and their concentrations. Correlations were proposed to predict the heat transfer characteristics such as average heat transfer coefficients as well as pressure drops of non-azeotropic refrigerant mixture flow condensation inside enhanced surface tubing. In addition, it was found that the refrigerant mixture's pressure drop is a weak function of the mixture composition.

Electronic Resource

1572-9893

Springer Online Journal Archives 1860-2000

Geography

Electronic Resource

1572-9893

Springer Online Journal Archives 1860-2000

Geography

Abstract The landform of Saudi Arabia in general and the Riyadh area in particular have their own potentiality for scenic and recreational purposes. The higher lands or features which have well cemented material in some areas of Riyadh have been recommended for scenic use, while lower lands like wide natural lakes, sand dunes and others can be mostly used for recreational purposes. Such features and purposes found here may be extrapolated into other similar areas within Saudi Arabia and may be compared with other areas elsewhere in the world.

Electronic Resource

0001-1541

Chemistry ; Chemical Engineering

Wiley InterScience Backfile Collection 1832-2000

Chemistry and Pharmacology

Process Engineering, Biotechnology, Nutrition Technology

The absorption of Cl2 into aqueous bicarbonate and aqueous hydroxide solutions was studied both experimentally and theoretically. The rate coefficient of the reaction between Cl2 and OH- was estimated over the temperature range of 293-312 K and fitted by the Arrhenius equation: \documentclass{article}\pagestyle{empty}\begin{document}$$ k_{24} = 3.56*10^{11} \exp \left({\frac{{ - 1,617}}{T}} \right) $$\end{document}.If Cl2 were assumed to react only with water and OH- in an aqueous bicarbonate solution, the predicted absorption rate would be much lower than that experimentally measured. This suggests that Cl2 reacts with HCO3- in an aqueous bicarbonate solution. The rate coefficient of the reaction between Cl2 and HCO3- was estimated over the temperature range of 293-313 K and fitted by the Arrhenius equation: \documentclass{article}\pagestyle{empty}\begin{document}$$ k_{21} = 5.63*10^{10} \exp \left({\frac{{ - 4,925}}{T}} \right) $$\end{document}.More importantly, under absorption conditions, the amount of hydroxide consumed for absorbing a specific amount of Cl2 into an aqueous hydroxide solution is almost twice the amount of bicarbonate consumed for absorbing the same amount of Cl2 into an aqueous bicarbonate solution.

5 Ill.

Electronic Resource

0029-5981

Engineering ; Engineering General

Wiley InterScience Backfile Collection 1832-2000

Mathematics

Technology

A numerical technique for the solution of two dimensional elasticity problems, referred to as The Method of Complex Finite Domains, is presented. The technique is based on assumed piecewise continuous fields of the Kolosov-Muskhelishvile complex potentials φ(z), Ψ(z). External loads and boundary conditions are modelled as continuous functions in terms of the functions' values at suitable quadrature points on the boundary. The method has a wide scope of applications because the structure of the complex potentials is known for many important regions and because of its flexiblity in modelling complex loads and boundary conditions. A numerical example that demonstrates the convergence and applicability of the method as well as the efficiency of the boundary load model is presented.

15 Ill.

Electronic Resource