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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 128: 674-80, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24694997

RESUMO

Experimental Raman and IR spectra of multiferroic [(CH3)2NH2][Ni(HCOO)3] were recorded at room temperature. The three-parameter hybrid B3LYP density functional method has been used with the 6-31G(d, p) basis set to derive the equilibrium geometry, atomic spin densities, vibrational wavenumbers, infrared intensities and Raman scattering activities. Based on these calculations, the assignment of the observed bands to the respective internal and lattice modes is proposed. The performed calculations revealed that the ν(NH2) stretching, ρ(NH2) rocking and τ(CH3) torsional modes are very sensitive to formation of the hydrogen bond between the DMA(+) cation and Ni-formate framework. Therefore, these modes are suitable probes for strength of hydrogen bonds in this family of metal-formate frameworks and study of their temperature dependence may provide significant information on a role of the hydrogen bonds in mechanism of the ferroelectric phase transition occurring in these compounds at low temperatures.


Assuntos
Compostos de Cálcio/química , Modelos Químicos , Níquel/química , Óxidos/química , Titânio/química , Espectrofotometria Infravermelho , Análise Espectral Raman
2.
Physiol Res ; 61(4): 405-17, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22670701

RESUMO

The aim of the study was to compare the bone mineral density (BMD) and body composition between ambulatory male MS patients and control subjects and to evaluate the relationships among body composition, motor disability, glucocorticoids (GC) use, and bone health. Body composition and BMD were measured by dual-energy X-ray absorptiometry in 104 ambulatory men with MS (mean age: 45.2 years) chronically treated with low-dose GC and in 54 healthy age-matched men. Compared to age-matched controls, MS patients had a significantly lower total body bone mineral content (TBBMC) and BMD at all measured sites except for the radius. Sixty five male MS patients (62.5 %) met the criteria for osteopenia and twenty six of them (25 %) for osteoporosis. The multivariate analysis showed a consistent dependence of bone measures (except whole body BMD) on BMI. The total leg lean mass % was as an independent predictor of TBBMC. The Expanded Disability Status Scale (EDSS), cumulative GC dose and age were independent determinants for BMD of the proximal femur. We conclude that decreasing mobility in male MS patients is associated with an increasing degree of osteoporosis and muscle wasting in the lower extremities. The chronic low-dose GC treatment further contributes to bone loss.


Assuntos
Densidade Óssea/fisiologia , Glucocorticoides/uso terapêutico , Esclerose Múltipla/tratamento farmacológico , Adulto , Composição Corporal/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/metabolismo
3.
Osteoporos Int ; 23(12): 2885-91, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22426952

RESUMO

UNLABELLED: A 12-month morning teriparatide (TPTD) administration resulted in a larger increase in the lumbar spine bone mineral density (BMD) than the evening application. The results indicate that the response of bone cells to teriparatide treatment depends on dosing time. INTRODUCTION: The aim of this study was to assess the long-term effects of the morning vs. the evening teriparatide administration on BMD and bone turnover markers (BTMs) in postmenopausal osteoporosis. METHODS: Fifty women with established postmenopausal osteoporosis were randomized to 12-month treatment with 20 µg of TPTD, administered daily in the morning or in the evening. The BMD and serum concentrations of C-terminal telopeptide of type I collagen, N-terminal propeptide of type I procollagen (PINP), and tartrate-resistant acid phosphatase isoform 5b (TRAP 5b) were measured at baseline, after 6 and 12 months. General linear model-repeated measurements were used to analyze the data. RESULTS: After 12 months, the lumbar spine BMD grew markedly (p < 0.001) with a significantly greater increase in the morning arm compared to the evening arm (9.1% vs. 4.8%, respectively, p < 0.05). The BMD at the distal radius significantly decreased (p < 0.001), with no differences between the arms. The BMD at proximal femur did not change significantly. After 6 months, the BTMs were significantly increased compared with baseline (p < 0.001). The increases in the evening arm vs. the morning arm, however, were more pronounced in PINP (+358% vs. +215%, respectively) and in TRAP 5b (+70% vs. +37%, respectively) (both p < 0.05). CONCLUSION: 12-month morning administration of TPTD resulted in a larger increase in the lumbar spine BMD than the evening application. The timing of TPTD administration may be important for its efficacy.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Osteoporose Pós-Menopausa/tratamento farmacológico , Teriparatida/administração & dosagem , Fosfatase Ácida/sangue , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/uso terapêutico , Cálcio/sangue , Colágeno Tipo I/sangue , Esquema de Medicação , Feminino , Humanos , Injeções Subcutâneas , Isoenzimas/sangue , Vértebras Lombares/fisiopatologia , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/fisiopatologia , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Fosfatos/sangue , Pró-Colágeno/sangue , Fosfatase Ácida Resistente a Tartarato , Teriparatida/uso terapêutico
4.
Osteoporos Int ; 21(12): 2027-36, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20135094

RESUMO

SUMMARY: The level of increased bone formation after 24 months of treatment with teriparatide (rhPTH (1-34), TPTD) is similar in patients who were either treatment-naïve (TN) or had lower bone turnover initially due to previous alendronate (ALN) therapy. INTRODUCTION: Bone anabolic effects of TPTD in postmenopausal women with osteoporosis may be blunted during the initial phase after switching from ALN to TPTD. To explore the long-term implications, we examined histomorphometric and biochemical markers of bone turnover of patients on TPTD therapy after long-term ALN treatment. METHODS: Paired biopsies were obtained after tetracycline double labeling at baseline and after 24 months of TPTD treatment from 29 ALN-pretreated (64.5 ± 16.4 months) and 16 TN patients. Biochemical markers were measured at baseline, during the treatment, or at study end. RESULTS: Compared with the baseline, after 24-month TPTD, activation frequency (Ac.F.) and osteoid surface (OS) increased in both groups: 0.11-0.34 cycles per year, 3.96-9.8% in the ALN-pretreated group and 0.19-0.33 cycles per year, 6.2-11.3% (p < 0.05) in the TN group, respectively. Biochemical and histomorphometric markers correlated positively both at baseline and endpoint. Serum amino terminal propeptide of type I procollagen (PINP) correlated with Ac.F. (r = 0.57, p < 0.001 and r = 0.48, p < 0.01) and OS (r = 0.51, p < 0.01 and r = 0.56, p < 0.01) at baseline and endpoint, respectively. Following 3 months of treatment, increases in biochemical markers like PINP predicted the increase in Ac.F. (r = 0.52, p < 0.01) and OS (r = 0.54, p < 0.01) after 24 months. CONCLUSIONS: The increased level of formation is similar in patients who were either TN or had lower bone turnover initially due to previous ALN therapy. Elevated bone formation in postmenopausal women with osteoporosis was sustained over a 24-month period by TPTD. Biochemical markers of bone formation are a good surrogate for the assessment of TPTD effects.


Assuntos
Alendronato/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Osteoporose Pós-Menopausa/tratamento farmacológico , Teriparatida/uso terapêutico , Adulto , Idoso , Biomarcadores/sangue , Biópsia , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Substituição de Medicamentos , Feminino , Colo do Fêmur/fisiopatologia , Humanos , Vértebras Lombares/fisiopatologia , Pessoa de Meia-Idade , Osteogênese/efeitos dos fármacos , Osteoporose Pós-Menopausa/patologia , Osteoporose Pós-Menopausa/fisiopatologia , Resultado do Tratamento
5.
J Phys Chem B ; 113(23): 8158-69, 2009 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-19453135

RESUMO

The crystal structure of the Cu(II) complex with Vitamin B(13) (orotic acid), cis-[Cu(oro)(NH(3))(2)] has revealed the presence of unusual, noncovalent pi-type interaction between the chelated Cu(II) ion and the C horizontal lineC bond of the uracilate ring [Michalska et al. Polyhedron 2007, 26, 4303]. In this work, the origin and strength of this interaction is thoroughly investigated. Comprehensive studies of the molecular structures and vibrational spectra of the title complex have been performed by using the unrestricted density functional theory methods, B3LYP, and the newly developed M05-2X functional. Calculations at the UMP2 level were also carried out for comparison. A variety of basis sets have been employed in the DFT calculations, including aug-cc-pVTZ, D95V(d,p), SDD, and LanL2DZ. The (63)Cu/(65)Cu isotope substitution technique was applied to identify the copper-ligand vibrations in the infrared spectra. The clear-cut assignment of all the bands in the FT-IR and Raman spectra of the title complex has been made on the basis of the calculated potential energy distribution, PED. It is shown that an extremely intense band at 1210 cm(-1) in the Raman spectrum of cis-[Cu(oro)(NH(3))(2)] is diagnostic for the N-1 deprotonation of the uracilate ring and coordination to the copper(II) ion. The B3LYP functional performs better than M05-2X in predicting vibrational frequencies of this complex in the solid state. Intermolecular interactions in crystal were modeled by the supramolecular system consisting of cis-[Cu(oro)(NH(3))(2)], ethylene (above), and formaldehyde (below the copper coordination plane). The stable structure of this system has been predicted only by the M05-2X and MP2 methods, which include dispersion energy, whereas the B3LYP calculations failed in geometry optimization. The distance between the Cu atom and the C horizontal lineC bond, predicted by the M05-2X method (3.00 A) is similar to the van der Waals contacts between the stacking bases in DNA. The calculated interaction energy between the chelated Cu(II) complex and ethylene amounts to -7.33 kcal mol(-1), which is similar to that determined for stacked uracil dimer. It is concluded that the London dispersion energy plays a significant role in the noncovalent interaction between the chelated Cu(II) ion and the uracilate ring in the crystal of cis-[Cu(oro)(NH(3))(2)]. Many copper enzymes in their active sites contain the chelated Cu(II) ion and the aromatic groups (Phe, Tyr and Trp) as the potential binding sites; therefore, the noncovalent copper(II)-pi interaction can be very important for the structure and functioning of these enzymes.


Assuntos
Quelantes/química , Cobre/química , Análise Espectral/métodos , Complexo Vitamínico B/química , Ligantes , Modelos Moleculares
6.
Calcif Tissue Int ; 76(2): 98-106, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15570400

RESUMO

To compare the ability of the bone mineral density (BMD) at the distal forearm, collagen I alpha 1 (COLIA1) polymorphism, and ultrasound stiffness to identify individuals with increased risk of wrist fracture, we studied 183 postmenopausal Czech women with a wrist fracture and 178 postmenopausal controls, ages 45-70 years. The genotypes "Ss" and "ss" were significantly overrepresented among fracture cases. The BMD measurements at the femoral neck, total femur, and distal forearm as well as ultrasound stiffness of the heel, broadband ultrasound attenuation (BUA), and speed of sound (SOS) were significantly lower in the fracture cohort. BMD of the distal forearm was the main determinant of susceptibility to the wrist fracture. Weight, the COLIA1 genotype, and ultrasound SOS further strengthened the predictive value of BMD. However, we found interaction between weight and both the COLIA1 Sp1 polymorphism and ultrasound parameters. Presence of the "s" allele as well as low SOS acted as significant predictors of wrist fracture only in heavier women, (> or =62 kg) but not in women with a body weight of less than 62 kg. In heavier women, both the COLIA1 Sp1 polymorphism and ultrasound parameters acted as independent markers that contributed to BMD to enhance fracture prediction. However, the COLIA1 enabled a higher specificity (specificity 72.4%, sensitivity 44.2%), whereas SOS enabled a higher sensitivity (sensitivity 73.9%, specificity, 45.7%). We conclude that BMD at total forearm, the COLIA1 polymorphism, and ultrasound SOS are independent predictors of wrist fracture in postmenopausal women. The effect of the COLIA1 Sp1 polymorphism and SOS on wrist fracture risk is more pronounced in patients with a higher body weight.


Assuntos
Peso Corporal , Calcâneo/diagnóstico por imagem , Colágeno Tipo I/genética , Fratura de Colles/genética , Fraturas Espontâneas/genética , Predisposição Genética para Doença , Polimorfismo Genético , Idoso , Densidade Óssea , Calcâneo/metabolismo , Estudos de Coortes , Colágeno Tipo I/metabolismo , Fratura de Colles/epidemiologia , Fratura de Colles/metabolismo , Feminino , Antebraço , Fraturas Espontâneas/epidemiologia , Fraturas Espontâneas/metabolismo , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/diagnóstico por imagem , Osteoporose Pós-Menopausa/epidemiologia , Osteoporose Pós-Menopausa/genética , Pós-Menopausa , Medição de Risco , Ultrassonografia
7.
Cas Lek Cesk ; 139(8): 231-6, 2000 Apr 26.
Artigo em Tcheco | MEDLINE | ID: mdl-10916211

RESUMO

BACKGROUND: The aim of the study was to determine the relationship between dual energy x-ray absorptiometry (DXA) and quantitative ultrasonometry (QUS) of calcaneus and their correlation with axial bone mineral density. METHODS AND RESULTS: 1284 subjects were tested for BMD (Bone Mineral Density) by DXA at the spine and hip (707 subjects by DPX-L, Lunar, and 577 subjects by QDR-4500 A, Hologic) and calcaneus (by PIXI, Lunar). The calcaneus was also measured using the QUS (Achilles Plus, Lunar), on the same day. The mean age of the patients was 56.5 +/- 11.6 years, mean height 166 cm, mean weight 70 kg. Three subjects were selected for precision error measurement with low, medium and high BMD of calcaneus (T-score of -2.2, -0.77 and 2.02, respectively) and scanned with re-positioning at the right heel (PIXI and Achilles Plus) 21 times on one day for short term precision error and over 21 consecutive days for long term precision error. The in vivo short term precision error of the heel measurement (BMD, SOS, BUA) in subjects with normal BMD was 0.67%, 0.47% and 1.87%, respectively; the long term in vivo precision error was 1.14%, 0.26% and 2.95%, respectively. No significant difference was found between BMD values on the right and left heel. A statistically significant correlation (p < 0.001) was found between BUA and BMD (r = 0.71), SOS and BMD (r = 0.73), Stiffness and BMD (r = 0.77). The heel BMD was also significantly correlated to BMD of the femoral neck (r = 0.64) and BMD of total femur (r = 0.70) and BMD of lumbar spine (r = 0.59). CONCLUSIONS: The DXA of the heel underestimates the prevalence of osteoporosis. The results of the heel QUS (Stiffness) appear to be better correlated to femoral BMD than heel BMD. The observed correlation coefficient of 0.77 between QUS and DXA at the heel was statistically significant, but it explains only 60% of variability of the QUS of the heel.


Assuntos
Absorciometria de Fóton , Densidade Óssea , Calcâneo/diagnóstico por imagem , Feminino , Fêmur/diagnóstico por imagem , Humanos , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Osteoporose/diagnóstico por imagem , Sensibilidade e Especificidade , Ultrassonografia
8.
Med Hypotheses ; 54(3): 472-4, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10783491

RESUMO

It is suggested that glutarimide moiety (2,6-piperidinedione) with the intact imide group (OC-NH-CO) and substituted at alpha or beta position in the ring, is acting as the carrier molecule (vector), which transports biologically active substituents (functional groups) through cell membranes. The results obtained from quantum chemical calculations and experimental studies indicate that structural features and physicochemical properties of glutarimide moiety are remarkably similar with those of uracil derivatives. Therefore, glutarimide drug may interact with specific receptors involved in transport of uracil and thymine nucleosides and it may easily cross biological membranes. (c) 2000 Harcourt Publishers Ltd.


Assuntos
Portadores de Fármacos , Piperidonas/metabolismo , Transporte Biológico , Membrana Celular/metabolismo
9.
Bone ; 26(3): 287-90, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10710003

RESUMO

Wrist fractures associated with postmenopausal women are only partially explained by osteoporosis. Recent studies have shown that polymorphism of an Spl binding site in the first intron of the collagen I alpha 1 gene (COLIA1) may determine risk for vertebral and nonvertebral fractures in post-menopausal women independent of bone mass. We investigated the relationship between the COLIA1 polymorphism, lumbar spine and femoral neck bone mineral density (BMD), ultrasound stiffness of the heel, anthropometric variables, and risk for wrist fractures in 126 Czech postmenopausal women with low bone mass who suffered one or more wrist fracture in the last 5 years and in 126 postmenopausal women with low bone mass without any fracture. Genotypes for the Spl COLIA1 polymorphism were determined by polymerase chain reaction, digestion with Ball restriction enzyme, and agarose gel electrophoresis. The test discriminates two alleles, S and s, which correspond to the presence of guanine and thymidine, respectively, at the first bases in the Spl-binding site in the first intron of the gene for CO-LIA1. No significant differences were found between the fracture and control group with regard to age, weight, and years since menopause. However, BMD of the lumbar spine and femoral neck and ultrasound stiffness of the heel were significantly lower in patients with prevalent wrist fracture. Femoral neck BMD was the strongest determinant of prevalent fracture of the wrist. COLIA1 genotyping significantly strengthened prediction of prevalent fracture of the wrist. After multivariate adjustment, women in the Ss group had 2.0 times the risk of the women in the SS group (95% confidence interval [CI] = 1.1-3.8), and the women in the ss group had 2.8 times the risk of the women in the SS group (95% CI = 0.5-14.6). The overall gene-dose effect was an odds ratio of 2.1 per copy of the "s" allele (95% CI = 1.2-3.8). In the stepwise logistic regression, COLIA1 acted synergistically with femoral neck BMD and weight in increasing prediction of wrist fracture. The results demonstrate that COLIA1 Sp1 polymorphism is associated with an increased risk of wrist fracture in postmenopausal women independent of BMD and may be helpful in clinical practice by identifying patients with an increased fracture risk.


Assuntos
Densidade Óssea/genética , Colágeno/genética , Fraturas Ósseas/genética , Polimorfismo Genético , Traumatismos do Punho/genética , Feminino , Fraturas Ósseas/fisiopatologia , Humanos , Pós-Menopausa , Traumatismos do Punho/fisiopatologia
10.
Eur J Clin Chem Clin Biochem ; 31(11): 765-71, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8305621

RESUMO

The blood plasma concentration of pseudouridine was estimated in 104 healthy adult subjects, and 108 patients suffering from malignant proliferative diseases. The HPLC method for simultaneous determination of pseudouridine and creatinine was applied. The average physiological concentration of pseudouridine in blood plasma was 2.43 +/- 0.97 mumol.l-1 or 29.15 +/- 7.40 mmol.mol-1 creatinine. The physiological urinary excretion of pseudouridine was 14.32 +/- 5.20 mumol.24 h-1.kg-0.75 or 19.60 +/- 5.22 mmol.mol-1 creatinine. Renal clearance of pseudouridine and endogenous creatinine were 4.04 +/- 0.99 and 5.50 +/- 1.46 ml.kg-0.75, respectively. A positive correlation (r = 0.55, P < 0.01) was found between age (in the range 20-92 years) and blood plasma pseudouridine concentration (mumol.l-1). By expressing plasma pseudouridine in relation to plasma creatinine, the apparent influence of non-metabolic factors (age, renal insufficiency, blood dilution) on the plasma pseudouridine concentration were largely excluded. Among haematological proliferative diseases the highest values of plasma pseudouridine concentrations were observed in chronic lymphocytic leukaemia (8.19 mumol.l-1; 54.9 mmol.mol-1 creatinine) and multiple myeloma (7.02 mumol.l-1; 52.5 mmol.mol-1 creatinine). In multiple myeloma, but not in chronic lymphocytic leukaemia, the plasma pseudouridine concentration depended on the clinical stage. A lower, but still significant response in non-Hodgkin's lymphoma was noted (4.03 mumol.l-1; 40.88 mmol.mol-1 creatinine). A significant increase of the plasma pseudouridine concentration was characteristic of adenocarcinomas of the large intestine, and it occurred in the early stages of malignant growth. In patients with lung cancer the plasma pseudouridine concentration was elevated only in advanced cases with metastases.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias/sangue , Pseudouridina/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Cromatografia Líquida de Alta Pressão , Creatinina/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/fisiopatologia , Neoplasias/urina , Pseudouridina/urina
11.
Eur J Clin Chem Clin Biochem ; 31(4): 205-9, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8318566

RESUMO

The HPLC method for the simultaneous determination of urinary neopterin, pseudouridine, and creatinine allows a rapid evaluation of the activation state of cell-mediated immunity, and the stimulation of whole-body rRNA + tRNA turnover, associated with malignant growth. Urinary neopterin and pseudouridine concentrations in healthy subjects amounted to: 106.6 +/- 34.6 mumol/mol creatinine, and 19.6 +/- 5.2 mmol/mol creatinine (mean +/- SD), respectively. The increase of neopterin excretion in patients with haematological neoplasms ranged from 146% in Hodgkin's disease to 534% in non-Hodgkin's lymphoma, whereas the increase in cancer cases ranged from 95% in adenocarcinoma of the gaster to 741% in hepatocellular carcinoma. The changes in pseudouridine excretion were much less pronounced: 63% in non-Hodgkin's lymphoma and 120% in carcinoma of the urinary bladder. The correlation coefficient between neopterin and pseudouridine was relatively low (r = 0.43), although statistically significant (P < 0.01). In the case of several neoplasms e.g. Hodgkin's disease, polycythaemia vera, and adenocarcinoma of the gaster, neopterin was significantly elevated, whereas pseudouridine remained at a normal concentration. There was a positive relationship between the stage of the disease (primary focus, regional metastases, dissemination) and urinary concentration of pseudouridine in patients with adenocarcinoma of the large intestine. In the same patients the increase of neopterin excretion was noticed both in early and advanced stages, with the highest values in disseminated disease.


Assuntos
Biopterinas/análogos & derivados , Creatinina/urina , Leucemia/urina , Linfoma/urina , Neoplasias/urina , Pseudouridina/urina , Análise de Variância , Biopterinas/urina , Cromatografia Líquida de Alta Pressão , Humanos , Neopterina , RNA de Transferência/metabolismo
12.
Nephron ; 64(2): 193-7, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8321350

RESUMO

The accumulation in blood plasma and efficiency of hemodialysis of pyrimidine compounds (orotic acid, orotidine, pseudouridine, uridine, thymine) as well as uric acid and creatinine in 23 patients with chronic renal failure (CRF) was investigated. As a reference, the analysis of the above metabolites in the plasma of 30 healthy volunteers was performed. Among examined compounds, pseudouridine possessed the highest capability of accumulation in blood plasma (25 times higher concentration than physiological). It coincided with the lowest efficiency of pseudouridine hemodialysis (44%) and the longest T1/2 (relative to creatinine) in plasma. A significant linear correlation (r = 0.81, p < 0.001) between efficiency of creatinine and pseudouridine hemodialysis was calculated. The concentration of orotic acid in the blood plasma of patients before hemodialysis exceeded 14 times its level in healthy subjects; the inhibition of uric acid synthesis by allopurinol in dialyzed patients was accompanied by enlargement of orotidine and orotate accumulation in blood plasma. Extremely high plasma concentration of examined pyrimidines remaining elevated after hemodialysis creates an additional hazard for tissue metabolism and health of patients with CRF.


Assuntos
Falência Renal Crônica/sangue , Falência Renal Crônica/terapia , Pirimidinas/sangue , Diálise Renal , Adulto , Idoso , Alopurinol/uso terapêutico , Creatinina/sangue , Feminino , Meia-Vida , Humanos , Falência Renal Crônica/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Ácido Orótico/sangue , Pseudouridina/sangue , Ácido Úrico/sangue , Uridina/análogos & derivados , Uridina/sangue
13.
Drugs Exp Clin Res ; 16(7): 343-9, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2092960

RESUMO

The essential biological importance of antineoplastons has motivated the present theoretical and experimental studies on the structure and potential binding sites of Antineoplaston A10, 3-phenylacetylamino-2,6-piperidinedione. Semi-empirical molecular orbital calculations SCF-LCAO-MO were performed using the MNDO method. The calculated molecular geometry of A10 is in very good agreement with the recently obtained X-ray structure of synthetic A10. Experimental investigations of the Raman spectra of A10 and its N,N-dideuterated derivative confirm the theoretical predictions concerning the structure and hydrogen bonding of A10. Analysis of calculated charge distribution reveals that the negative charges are localized on the ring nitrogen and on the exocyclic oxygen atoms of A10 and are similar to the corresponding charges computed for some pyrimidine bases. This indicates that Antineoplaston A10 may have similar binding sites. It is concluded that the mechanism of action of Antineoplaston A10 may in part be related to its structural and chemical resemblance with deoxythymidine and uridine. A10 may act as a nucleoside antagonist and interact very closely with adenosine units in nucleic acids and enzymes, which may interfere with protein synthesis in neoplastic cells.


Assuntos
Antineoplásicos/química , Benzenoacetamidas , Piperidinas/química , Piperidonas , Antineoplásicos/farmacocinética , Sítios de Ligação , Computação Matemática , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Piperidinas/farmacocinética
14.
Carbohydr Res ; 131(1): 29-38, 1984 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-6091879

RESUMO

Time-dependent, Fourier-transform infrared spectra of solutions of lyxose in H2O and D2O were measured, in order to identify the vibrational bands characteristic of each anomer. The anomeric C-H stretching and deformation bands, and also the anomeric C-O stretching bands, were identified.


Assuntos
Pentoses , Configuração de Carboidratos , Fenômenos Químicos , Química , Deutério , Óxido de Deutério , Análise de Fourier , Espectrofotometria Infravermelho/métodos , Água
15.
Int J Pediatr Otorhinolaryngol ; 6(3): 279-83, 1983 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6609903

RESUMO

In the time period from February 1980 to October 1981, 179 children with upper respiratory tract infections and 67 healthy controls were investigated in Warsaw. The clinical condition of the studied children, the types of the obtained H. influenzae strains and their sensitivity to the antibiotics and sulphamides used most frequently in clinical practice were analyzed.


Assuntos
Antibacterianos/farmacologia , Infecções por Haemophilus/microbiologia , Infecções Respiratórias/microbiologia , Adolescente , Criança , Pré-Escolar , Resistência Microbiana a Medicamentos , Haemophilus influenzae/efeitos dos fármacos , Humanos , Lactente , Laringite/microbiologia , Polônia , Sinusite/microbiologia , Sulfanilamidas/farmacologia
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