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1.
Nat Commun ; 8: 15529, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28569742

RESUMO

The Einstein equivalence principle (EEP) has a central role in the understanding of gravity and space-time. In its weak form, or weak equivalence principle (WEP), it directly implies equivalence between inertial and gravitational mass. Verifying this principle in a regime where the relevant properties of the test body must be described by quantum theory has profound implications. Here we report on a novel WEP test for atoms: a Bragg atom interferometer in a gravity gradiometer configuration compares the free fall of rubidium atoms prepared in two hyperfine states and in their coherent superposition. The use of the superposition state allows testing genuine quantum aspects of EEP with no classical analogue, which have remained completely unexplored so far. In addition, we measure the Eötvös ratio of atoms in two hyperfine levels with relative uncertainty in the low 10-9, improving previous results by almost two orders of magnitude.

2.
Eur Rev Med Pharmacol Sci ; 19(4): 682-93, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25753887

RESUMO

OBJECTIVE: Caffeic acid, predominantly as esters linked to quinic acid (chlorogenic acids), is a phenolic acid present at high levels in coffee. The aim of the study was to investigate effects of caffeic and chlorogenic acids on the skeletal system of female rats with normal estrogen levels and estrogen-deficient. MATERIALS AND METHODS: Caffeic acid (5 and 50 mg/kg p.o. daily) and chlorogenic acid (100 mg/kg p.o. daily) were administered for 4 weeks to non-ovariectomized and bilaterally ovariectomized mature Wistar rats, and their effects were compared with appropriate controls. Moreover, estradiol (0.2 mg/kg p.o. daily) was administered to ovariectomized rats. Bone turnover markers, mass, mineralization and mechanical properties were examined. RESULTS: Although caffeic acid at a low dose exerted some unfavorable effects on the skeletal system, at high doses, caffeic and chlorogenic acids slightly increased mineralization in the tibia and improved mechanical properties of the femoral diaphysis (compact bone). Unlike estradiol, they did not counteract the worsening of the tibial metaphysis bone strength (cancellous bone) and increases in osteocalcin concentration induced by estrogen deficiency. CONCLUSIONS: High doses of the phenolic acids slightly favorably affected the rat skeletal system independently of the estrogen status.


Assuntos
Osso e Ossos/efeitos dos fármacos , Ácidos Cafeicos/farmacologia , Ácido Clorogênico/farmacologia , Animais , Relação Dose-Resposta a Droga , Estradiol/sangue , Estradiol/farmacologia , Estrogênios/farmacologia , Feminino , Fêmur/efeitos dos fármacos , Humanos , Osteocalcina/sangue , Ovariectomia , Ratos , Ratos Wistar , Tíbia/efeitos dos fármacos
3.
Eur J Pharm Biopharm ; 88(3): 1094-104, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25460155

RESUMO

Different experimental and theoretical techniques were applied to investigate basic physical properties of very stable and homogeneous solid dispersions formed by itraconazole and octaacetylmaltose. Differential scanning calorimetry as well as semi-empirical calculations have indicated that liquid crystalline ordering in itraconazole was completely suppressed in the binary mixtures. Molecular dynamics studies with the use of broadband dielectric spectroscopy have shown that the width of the structural relaxation process becomes smaller and fragility drops in solid dispersions with respect to the pure itraconazole. Moreover, the dynamics of secondary relaxation processes was affected by acetylated maltose. As demonstrated, ß- and γ-secondary modes shift to higher and lower frequencies, respectively. On the other hand, aging experiments revealed that isostructural relaxation times in the glassy state become systematically longer with the addition of modified carbohydrate. This is a very important finding in the context of the current discussion on the factors affecting physical stability of easily crystallizing APIs. It seems that beside intermolecular interactions and local reorientation, the global mobility might control the crystallization of amorphous solid dispersions. Finally, we have demonstrated that itraconazole in binary mixtures dissolves faster and to greater extent with respect to the crystalline and amorphous form of this API.


Assuntos
Química Farmacêutica/métodos , Temperatura Baixa , Excipientes/química , Itraconazol/química , Cristais Líquidos/química , Maltose/química , Acetilação , Peso Molecular , Difração de Raios X
4.
Eur Rev Med Pharmacol Sci ; 18(13): 1937-47, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25010626

RESUMO

BACKGROUND AND AIM: An example of a medicinal plant with numerous potential activities is fenugreek (Trigonella foenum-graecum L.). The aim of the present study was to investigate the effects of fenugreek seed on bone mechanical properties in rats with normal and decreased estrogen level (developing osteoporosis). MATERIALS AND METHODS: The experiments were carried out on 3-month-old non-ovariectomized (NOVX) and ovariectomized (OVX) Wistar rats, divided into control rats, rats receiving pulverized fenugreek seed (1% in the diet) and rats receiving fenugreek seed extract standardized for 4-hydroxy-L-isoleucine (50 mg of 4-hydroxy-L-isoleucine/kg p.o. daily) for 4 weeks. Serum bone turnover markers, bone mineralization and mechanical properties were examined. RESULTS: Fenugreek seed added to food did not significantly affect bone mineralization and serum turnover markers, independently of the estrogen status. It tended to increase the strength of the tibial metaphysis (cancellous bone) in NOVX rats, and increased the strength of the femoral diaphysis (compact bone) in OVX rats. The fenugreek seed extract did not affect the skeletal system of NOVX rats, and significantly worsened mineralization of the vertebra in OVX rats, decreased due to estrogen deficiency. CONCLUSIONS: Low dietary intake of fenugreek seed may exert slight favorable skeletal effects, whereas at high doses it may damage the skeletal system.


Assuntos
Fêmur/efeitos dos fármacos , Extratos Vegetais/farmacologia , Tíbia/efeitos dos fármacos , Animais , Fenômenos Biomecânicos , Peso Corporal/efeitos dos fármacos , Calcificação Fisiológica/efeitos dos fármacos , Dieta , Relação Dose-Resposta a Droga , Estradiol/sangue , Estradiol/farmacologia , Feminino , Fêmur/fisiologia , Ovariectomia , Ratos Wistar , Sementes , Estresse Mecânico , Tíbia/fisiologia , Trigonella
5.
Plant Biol (Stuttg) ; 14(2): 285-94, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21972995

RESUMO

For 4 years we studied pollination biology and breeding system of the critically endangered, Red List plant Fritillaria meleagris L. (Liliaceae), in the larger of the two remaining populations of the plant in SE Poland. Our observations indicated that, contrary to literature data, the species is not dichogamous nor is it obligatorily out-crossing. Selfing, although rare in natural populations, results in fully developed seeds. Flowers are visited by several insect species, mostly social and solitary bees. In spite of extremely low visitation rates to this early spring-flowering plant, the species is not pollen limited. Although the largest pollen loads are transferred by solitary bees, the key pollinators are bumblebees (mostly the most common species, Bombus terrestris and B. lapidarius) due to their seasonal and floral constancy, and tolerance of bad weather conditions. The current decline of the studied population seems not to be related to the species' pollination or breeding systems but to plant habitat loss. It is suggested, however, that in smaller populations, the species' dependence on generally rare pollinators and largely out-crossed breeding system may accelerate local extinction.


Assuntos
Abelhas/fisiologia , Fritillaria/fisiologia , Polinização/fisiologia , Animais , Cruzamento , Ecossistema , Flores/crescimento & desenvolvimento , Flores/fisiologia , Fritillaria/crescimento & desenvolvimento , Polônia , Dinâmica Populacional , Reprodução/fisiologia , Sementes/crescimento & desenvolvimento , Sementes/fisiologia
7.
Folia Med Cracov ; 42(4): 263-71, 2001.
Artigo em Polonês | MEDLINE | ID: mdl-12815787

RESUMO

UNLABELLED: We studied plasma levels of troponin I (cTnI), troponin T (cTnT), creatine kinase MB (CKMBmass) and myoglobin (MB) in patients undergoing coronary artery bypass surgery with extracorporeal circulation and cardioplegia. In group 1 (25 patients without perioperative myocardial infarction) plasma levels of all markers studied were elevated after operation. In group 2 (24 patients with perioperative myocardial infarction) plasma concentrations of all markers exceeded several times levels observed in patients without myocardial infarction with maximal value for MB at 12 hours after operation; for cTnI and CKMBmass at 16 hours after surgery and for cTnT at 32 hours after the end of operation. ROC curves show cut-off value for CKMBmass 20.3 ng/ml (sensitivity 79% and specificity 89%); for cTnI cut-off value was 0.8 ng/ml (sensitivity 80% and specificity 94%) for cTnT the cut-off value was 0.41 ng/ml (sensitivity 86% and specificity 88%) and for MB the cut-off value was 419 ng/ml (sensitivity 85% and specificity 70%). CONCLUSION: All markers studied are reliable biochemical tests for perioperative myocardial infarction, however, the analysis of ROC curves suggested that cTnI and cTnT might be more useful for diagnosis of perioperative myocardial infarction after conventional coronary artery bypass surgery.


Assuntos
Ponte de Artéria Coronária/efeitos adversos , Creatina Quinase/sangue , Isoenzimas/sangue , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Mioglobina/análise , Troponina I/análise , Troponina T/análise , Idoso , Biomarcadores/sangue , Creatina Quinase Forma MB , Circulação Extracorpórea , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/prevenção & controle , Mioglobina/sangue , Assistência Perioperatória , Cuidados Pós-Operatórios , Troponina I/sangue , Troponina T/sangue
8.
Acta Biochim Pol ; 47(2): 349-53, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11051199

RESUMO

Galactosamine (GalN), a well-known hepatotoxin that depletes the cellular pool of uracil nucleotides, was previously shown to have greater impact on the inhibition of protein synthesis in hepatocytes of old rats as compared with young animals (Kmiec 1994, Ann. N.Y. Ac. Sci. 717, 216-225). In the present study we compared the effects of GalN on the nucleotide content (measured by ion-exchange HPLC) in the livers of young (4 months), adult (12 months), and old (24-26 months old) rats two hours after its intraperitoneal administration. UTP content of the livers of old control rats was significantly lower (by 28%) than that of young animals. GalN administration decreased the UTP content in the livers of young, adult and old rats by, respectively, 55%, 65% and 89%, and increased the content of UDP-sugars by 189%, 175% and 305%. The hepatic content of ATP, ADP, AMP, NAD, GTP except CTP did not differ significantly among the age groups of rats studied, and was not changed by GalN treatment. The content of CTP was significantly higher in old rats (P < 0.03) upon GalN treatment. The lower hepatic content of UTP may partially explain the increased sensitivity of hepatocytes and livers of old rats to the action of galactosamine, and possibly to other hepatotoxic compounds that decrease transcription in the liver.


Assuntos
Galactosamina/farmacologia , Fígado/crescimento & desenvolvimento , Uridina Trifosfato/metabolismo , Envelhecimento , Alanina Transaminase/sangue , Animais , Glucosamina/análogos & derivados , Glucosamina/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Ratos , Ratos Wistar , Uridina Difosfato Ácido Glucurônico/metabolismo , Uridina Difosfato N-Acetilgalactosamina/análogos & derivados , Uridina Difosfato N-Acetilgalactosamina/metabolismo
9.
Cancer Lett ; 152(2): 123-7, 2000 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-10773402

RESUMO

Individual sensitivity to mutagens has been considered to play an important role in head-and-neck squamous cells carcinoma (HNSCC) development. The bleomycin test was introduced for establishing constitutional susceptibility to mutagens (T.C. Hsu, D.A. Johnston, L.M. Cherry, D. Ramkisson, S.P. Schantz, J.M. Jessup, R.J. Winn, L. Shirley, C. Furlong, Sensitivity to genotoxic effects of bleomycin in humans: possible relationship to environmental carcinogenesis, Int. J. Cancer 43 (1989) 403-409). Its criteria are based on scoring of chromosome aberrations (CAs, mainly breaks) in Giemsa-stained chromosomes. Fluorescence in situ hybridization (FISH) offers an easy method for analysis of translocations, acentric fragments and dicentrics. In the present study FISH was applied in the analysis of bleomycin-induced CAs of the HNSCC patients and controls. The results proved that FISH is a complementary method to the classical staining in monitoring of bleomycin-induced CAs.


Assuntos
Bleomicina/efeitos adversos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Aberrações Cromossômicas , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Hibridização in Situ Fluorescente , Adulto , Idoso , Corantes Azur , Estudos de Casos e Controles , Cromossomos Humanos Par 4 , Cromossomos Humanos Par 5 , Dano ao DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Med Sci Monit ; 6(1): 141-4, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11208302

RESUMO

BACKGROUND: Congenital malformation syndromes are often caused by unbalanced chromosome translocations, which appear spontaneously or may be inherited from a healthy parent being the carrier of a balanced reciprocal translocation (rcp). Breakpoints, underlying chromosome fragment exchanges, may be located at any point of any chromosome and therefore, an infinite number of different translocations is possible. Special emphasis is placed both on the clinical characterization of every rare chromosomal aberration syndrome and on the determination of its breakpoints. OBJECTIVES: Diagnosis of a 8q22-->qter duplication in a child with multiple congenital malformations. MATERIAL AND METHODS: We determined the karyotypes of the five members of proband's family were established by using classical cytogenetic methods on whole blood obtained by venipuncture. RESULTS: We described a rare familial reciprocal translocation t(8; 14), observed in balanced form in mother and one healthy son, while being unbalanced in the son with congenital malformations. CONCLUSIONS: Balanced chromosome 8 aberration carriers should be aware of the procreation risks and need genetic counseling.


Assuntos
Anormalidades Múltiplas/genética , Aberrações Cromossômicas , Cromossomos Humanos Par 8/genética , Translocação Genética , Anormalidades Múltiplas/patologia , Cromossomos Humanos Par 14/genética , Ossos Faciais/anormalidades , Feminino , Genitália Masculina/anormalidades , Humanos , Lactente , Cariotipagem , Masculino , Linhagem
13.
Biochim Biophys Acta ; 1452(2): 145-50, 1999 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-10559467

RESUMO

Adenine (ADE) reutilisation is an important pathway of adenylate pool regeneration. Data on the rate of this process in different types of cells, its regulation and the importance of species differences is limited. In this study we evaluated adenine incorporation rate and the effect of metabolic factors on this process in human and rat endothelium and compared it to adenine phosphoribosyltransferase (APRT) activity. Microvascular endothelial cells from human (HE) and rat (RE) hearts and a transformed human microvascular endothelial cell line (HMEC-1) were investigated. The rate of adenine incorporation into the adenine nucleotide pool under control conditions was 3.1+/-0.3, 82.8+/-11.1 and 115.1+/-11.2 pmol/min per mg protein for HE, RE and HMEC-1, respectively. In the presence of 2.5 mM ribose or elevated inorganic phosphate concentration in the medium (4.8 mM), few changes were observed in all types of cells. In the presence of both ribose and high inorganic phosphate, the rate of adenine incorporation for RE and HMEC-1 was not significantly different from control, while in HE the rate of adenine incorporation into adenine nucleotides was increased by 75%. Activities of APRT in RE and HMEC-1 were 237.7+/-23.2 and 262.0+/-30.6 pmol/min per mg protein respectively while the activity in HE was markedly lower 48.7+/-3.0 pmol/min per mg protein. In conclusion, nucleotide synthesis from adenine seems to be a slow process in human cardiac microvascular endothelium but it is fast and efficient in rat heart microvascular endothelial cells. Low APRT activity in normal human endothelial cells seems to be the most likely mechanism for this. However, adenine incorporation rate and APRT activity could be greatly enhanced in human endothelium, as demonstrated in transformed cells.


Assuntos
Adenina/metabolismo , Endotélio Vascular/metabolismo , Adenina Fosforribosiltransferase/metabolismo , Animais , Capilares/metabolismo , Radioisótopos de Carbono , Linhagem Celular Transformada , Células Cultivadas , Humanos , Miocárdio/metabolismo , Fosfatos/farmacologia , Ratos , Ribose/farmacologia
14.
J Mol Cell Cardiol ; 30(3): 673-83, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9515042

RESUMO

The objective of the present study was to establish the optimal combination of inhibitors of adenosine metabolism and nucleotide precursors resulting in long-term increase in endogenous adenosine concentration without adverse metabolic consequences in non-ischemic cardiomyocytes and endothelial cells. Cardiomyocytes and endothelial cells were isolated after collagenase digestion of the rat heart. Freshly isolated cardiac myocytes or cultured endothelial cells were incubated for up to 8 h with no inhibitors or substrates or with various combinations of adenosine deaminase inhibitor: 5 micron M erythro-9(2-hydroxy-3-nonyl)adenine (EHNA), adenosine kinase inhibitors: 10 micro M 5'-iodotubercidin (ITu) or 10 micro M 5'-aminoadenosine (AA) and nucleotide precursors: 100 micro M adenine, 2.5 mm ribose and 5 mm inorganic phosphate. Nucleotide, nucleoside and base concentrations were evaluated at the end of the incubation by HPLC in cardiomyocyte or endothelial cells extracts and in incubation media. Adenosine content in cardiomyocyte suspension was enhanced after 3 h incubation in the presence of ITu+EHNA as compared to EHNA alone (2.8+/-0.2 v 0.9+/-0.2 nmol/mg protein, respectively). ATP decreased from an initial value of 22.7+/-0.7 nmol/mg protein to 18.9+/-0.7 in the presence of ITu+EHNA, while ATP was maintained at 21.8+/-0.7 nmol/mg protein with EHNA. With adenine+ITu+EHNA, the changes were similar to those observed with ITu+EHNA. However, with ribose+adenine+ITu+EHNA, ATP increased to 25. 8+/-1.2 nmol/mg protein and adenosine concentration was elevated to 3.9+/-0.3 nmol/mg protein. Similar results were observed if AA was used instead of ITu to inhibit adenosine kinase. All the changes were maintained after 8 h of incubation. Adenosine content was increased in endothelial cells incubated with ITu+EHNA to 3.1+/-0.4 nmol/mg protein as compared to 1.1+/-0.2 nmol/mg protein with EHNA alone after 3 h, while ATP decreased (18.1+/-1.1 v 22.0+/-1.4 nmol/mg protein with EHNA+ITu or EHNA, respectively). In the presence of adenine+ITu+EHNA, adenosine content increased after 3 h to 6.5+/-0.9 nmol/mg protein while ATP was elevated to 26.1+/-0.8 nmol/mg protein. Additional presence of ribose was without effect. No changes in adenylate energy charge were observed in cardiomyocytes or endothelium under any conditions studied. Inhibition of adenosine kinase and adenosine deaminase caused a decrease in ATP together with increased adenosine content both in endothelial cells and cardiomyocytes. However, the addition of adenine (endothelial cells) or adenine with ribose (cardiomyocytes) together with inhibitors of adenosine metabolism protected cells from ATP depletion and further increased adenosine concentration.


Assuntos
Adenina/metabolismo , Trifosfato de Adenosina/metabolismo , Adenosina/biossíntese , Miocárdio/metabolismo , Ribose/metabolismo , Adenina/análogos & derivados , Adenina/farmacologia , Adenosina Quinase/antagonistas & inibidores , Animais , Células Cultivadas , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Inibidores Enzimáticos/farmacologia , Coração/efeitos dos fármacos , Técnicas In Vitro , Cinética , Masculino , Miocárdio/citologia , Purinas/metabolismo , Ratos , Ratos Sprague-Dawley , Tubercidina/análogos & derivados , Tubercidina/farmacologia , Uridina/metabolismo
17.
Ann Thorac Surg ; 62(2): 469-74, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8694607

RESUMO

BACKGROUND: Ischemic preconditioning (IP) can reduce lethal injury to the myocardium induced by prolonged ischemia. However, little is known about the effect of preconditioning on the heart subjected to cardioplegic arrest and hypothermic preservation. We evaluated the effect of IP on myocardial metabolism, mechanical performance, and coronary endothelial function after cardioplegic arrest and prolonged hypothermic preservation. METHODS: An isovolumic Langendorff perfused rat heart model was used, and hearts were divided into two groups. The first group (IP, n = 14) was preconditioned by 5 minutes of global normothermic (37 degrees C) ischemia followed by 10 minutes of normothermic reperfusion before 6 hours of cold (4 degrees C) preservation, followed by 60 minutes of reperfusion. The second group (control, n = 15) was subjected to 6 hours of cold preservation followed by 60 minutes of reperfusion without preconditioning. Mechanical function was assessed using left ventricular balloon by constructing pressure-volume curves in two ways: at defined left ventricular volumes or at defined left ventricular end-diastolic pressures. Initially, the volume of the balloon was increased incrementally from 0 to 150 microL in 25-microL steps. Measurements were then repeated with loading balloon to achieve left ventricular end-diastolic pressure of 5, 10, 15, or 20 mm Hg. Myocardial function was assessed before ischemia and at 15 or 60 minutes of reperfusion. Metabolic status of the heart was evaluated by measuring the release of purine catabolites during the initial 15 minutes of reperfusion and concentrations of myocardial nucleotides at the end of reperfusion. Endothelium-mediated vasodilatation was evaluated using 10 mumol/L 5-hydroxytryptamine before and after ischemia. RESULTS: Left ventricular end-diastolic pressure values were significantly lower in the IP group, by 20% to 40%, during the reperfusion phase at each volume of the balloon compared with the control group. The rate-pressure product was more favorable during reperfusion in the IP than in the control group because of a 15% increased heart rate in the IP group. The release of purine catabolites from the heart during the reperfusion phase was reduced (p < 0.01) in the IP group (0.66 +/- 0.04 mumol) relative to the control group (0.92 +/- 0.06 mumol). No difference in the recovery of systolic function, myocardial adenosine triphosphate concentration, or endothelial function was observed between the groups. CONCLUSIONS: Under conditions of cardioplegic arrest and hypothermic preservation, IP can offer additional protection for the heart by preventing an increase in diastolic stiffness. However, metabolic improvement or better preservation of the systolic or endothelial function was not observed in this model.


Assuntos
Circulação Coronária , Parada Cardíaca Induzida , Coração/fisiopatologia , Trifosfato de Adenosina/análise , Animais , Volume Cardíaco , Vasos Coronários/fisiopatologia , Endotélio Vascular/fisiopatologia , Frequência Cardíaca , Hipertermia Induzida , Masculino , Contração Miocárdica , Reperfusão Miocárdica , Miocárdio/metabolismo , Nucleotídeos/análise , Purinas/análise , Ratos , Ratos Wistar , Serotonina , Agonistas do Receptor de Serotonina , Fatores de Tempo , Vasodilatação , Função Ventricular Esquerda , Pressão Ventricular
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