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101.
Wojciech P. Ozimiński Piotr Garnuszek Jan Cz. Dobrowolski 《Inorganica chimica acta》2007,360(6):1902-1914
The Pt(II) and Pt(IV) complexes with histamine were calculated by using more than 20 DFT functionals and various basis sets. Based on the comparison between the X-ray and theoretical geometrical parameters of the Pt(II)(Hist)Cl2 complex the MPW1PW91, OPW91 and SVWN5 functionals combined with the 6-311G∗∗ basis set for non-metallic and SDD (ECP) basis set for platinum were found to yield the most satisfactory agreement. The structure of the Pt(II) complex with iodohistamine important for pharmacy, so far isolated only in minute amounts, was predicted by using the MPW1PW91 functional. Comparison of the theoretical NMR chemical shifts of the Pt(II)(Hist)Cl2 complex with those found experimentally have shown that the theoretical 1H and 13C NMR chemical shifts are in plausible agreement with the experimental ones, whereas the theoretical 195Pt chemical shifts fit the experimental values only when the relativistic approach is applied within the ZORA formalism. We confirmed suitability of the three selected functionals for reproduction of the experimental structure of Pt complexes at fourth oxidation state by using the cis- and ions as models. Finally, with the selected theoretical methods, the structures and stabilities of four Pt(IV)(Hist)2Cl2 complex isomers were predicted. 相似文献
102.
Achromatopsia (ACHM) or rod monochromacy is an autosomal recessive and genetically heterogeneous retinal disorder. It is characterized
by a lack of color discrimination, poor visual acuity, photodysphoria, pendular infantile nystagmus, and abnormal photopic
electroretinographic (ERG) recordings with preservation of rod-mediated function. Mutations in three known genes are causative;
including genes for the α and β subunits of the cyclic nucleotide-gated cation channel (CNGA3 and CNGB3, respectively) and cone photoreceptor transducin—GNAT2. We investigated the prevalence of mutations in achromatopsia-causing genes in a cohort of 16 families with both clinical
and electrophysiologic evidence consistent with autosomal recessive transmission, including one subject with achromatopsia
and maternal isodisomy for chromosome 14. The most frequent mutation, p.T383fsX in CNGB3, accounted for 75% (18/24) of disease-associated alleles; intragenic SNPs in unrelated patients revealed transmission of
a common haplotype consistent with a founder effect. Homozygous p.T383fsX mutation in CNGB3 that maps to chromosome 8 was detected in a patient with achromatopsia and systemic features associated with uniparental
disomy (UPD) of chromosome 14. Two novel variants, p.R223G and p.A621E were found in CNGA3. We conclude that CNGA3 and CNGB3 mutations are responsible for the substantial majority of achromatopsia. Furthermore, the CNGB3 mutation p.T383fsX is a predominant mutation, results from a founder effect, and is responsible for the ACHM in the original
clinical report of UPD 14. 相似文献
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104.
Molecular basis of human CD36 gene mutations 总被引:1,自引:0,他引:1
CD36 is a transmembrane glycoprotein of the class B scavenger receptor family. The CD36 gene is located on chromosome 7 q11.2 and is encoded by 15 exons. Defective CD36 is a likely candidate gene for impaired fatty acid metabolism, glucose intolerance, atherosclerosis, arterial hypertension, diabetes, cardiomyopathy, Alzheimer disease, and modification of the clinical course of malaria. Contradictory data concerning the effects of antiatherosclerotic drugs on CD36 expression indicate that further investigation of the role of CD36 in the development of atherosclerosis may be important for the prevention and treatment of this disease. This review summarizes current knowledge of CD36 gene structure, splicing, and mutations and the molecular, metabolic, and clinical consequences of these phenomena. 相似文献
105.
Czerwińska E Marcinowska-Suchowierska E Walicka M Lisik W Wierzbicki Z 《Endokrynologia Polska》2007,58(2):130-138
INTRODUCTION: Obese patients may have abnormal calcium homeostasis because of unbalanced diet and decreased sun exposure. Bariatric surgery itself may lead to disturbances in calcium homeostasis (and in consequence changes in bone mass) or increase preexisting metabolic derangements. The aim of the study was: 1. To assess calcium homeostasis and biochemical markers of bone turnover in patients with morbid obesity. 2. To determine the impact of bariatric surgery on parameters mentioned above. 3. To establish recommendations for supplementation with calcium and vitamin D in morbidly obese patients after bariatric surgery. MATERIAL AND METHODS: Serum calcium, parathormone (PTH), vitamin D (25(OH)D), biochemical markers of bone turnover (beta-CrossLaps as a marker of bone resorption and osteocalcin as a marker of bone formation) and urine calcium as well as fat mass, lean mass and bone mineral content (by DXA) were measured before bariatric surgery of the stomach (VBG or GBP) in 57 morbidly obese patients (48 women, 9 men; mean age 35.9 y). The same procedures were repeated six months after operation in 28 of them (24 women, 4 men). Daily calcium intake was also determined based on food questionnaire. RESULTS: Biochemical findings in the group of patients before bariatric surgery were as follows: serum calcium, beta-CrossLaps and urine calcium were within normal range, PTH concentration was increased to 81.0 pg/ml and 25(OH)D as well as osteocalcin concentration decreased (4.9 ng/ml and 13.6 ng/ml, respectively). Six months after bariatric surgery there was no change in serum and urine calcium, PTH concentration decreased to normal level (46.8 pg/ml), 25(OH)D concentration increased to 6.5 ng/ml (not significant) and still remained below normal range. Markers of bone turnover--both resorption and formation--increased (beta-CrossLaps over normal range to 0.594 ng/ml, osteocalcin to normal range 26.8 ng/ml). Daily calcium intake was below RDA before and after bariatric procedure. CONCLUSIONS: 1. Patients with morbid obesity have secondary hyperparathyroidism and deficiency of vitamin D. 2. Abrupt weight loss after bariatric surgery is accompanied by the regression of secondary hyperparathyroidism, decrease of the deficiency of vitamin D and increase in bone turnover. 3. Supplementation with vitamin D and calcium is recommended for patients with morbid obesity after bariatric surgery. 相似文献
106.
107.
Koszytkowska-Stawińska M Kaleta K Sas W De Clercq E 《Nucleosides, nucleotides & nucleic acids》2007,26(1):51-64
Aza-analogues of Acyclovir were obtained from N-(2-pivaloyloxyethyl)-N-(pivaloyloxymethyl)-p-toluenesulfonamide via a one-pot base silylation/nucleoside coupling procedure. The antiviral activities of all aza-nucleosides in vitro against a variety of viruses were evaluated. None of these compounds displayed any specific antiviral effects. 相似文献
108.
109.
110.
Anna Sankiewicz Piotr Laudanski Lech Romanowicz Adam Hermanowicz Wiesława Roszkowska-Jakimiec Wojciech Debek Ewa Gorodkiewicz 《Analytical biochemistry》2015
We have developed a new method for highly selective determination of the ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1) concentration using a surface plasmon resonance imaging (SPRI) technique and two different biosensors. UCH-L1 was captured from a solution by immobilized specific rabbit monoclonal antibody or specific LDN-57444 inhibitor due to formation of receptor–UCH-L1 complex on the biosensor surface. The analytically useful dynamic response range of both biosensors is between 0.1 and 2.5 ng/ml. The detection limit is 0.06 ng/ml for the biosensor with antibody and 0.08 ng/ml for the biosensor with inhibitor. Biosensors based on both antibody and inhibitor were found to be suitable for quantitative determination of the UCH-L1 and exhibit good tolerance to the potential interferents. Both biosensors gave comparable results in the range of 0 to 0.20 ng/ml for plasma samples and 0.30 to 0.49 ng/ml for cerebrospinal fluid samples. To validate the new methods, comparative determination of UCH-L1 by the commercial enzyme-linked immunosorbent assay (ELISA) kit was performed. In general, in terms of UCH-L1 concentration, a good correlation between SPRI and ELISA was found. The developed biosensors can be used successfully for the determination of UCH-L1 in body fluids. 相似文献