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1.
Physiol Res ; 68(3): 419-429, 2019 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-30904006

RESUMO

The aim of this study was to evaluate the effects of exposure to 30 daily whole body cryostimulation (WBC) on lipid metabolic parameters and serum HSP-70 concentration. The study involved 45 volunteers, homogeneous in terms of diet and daily physical activity. Blood samples were collected before and after the 10(th), the 20(th), and the 30(th) session and one month after the intervention. Total cholesterol, HDL, TG concentrations and Apolipoprotein A-I, ApoB and HSP-70 protein levels were determined in serum. Additionally, the LI (Lipid Index) and the LDL level were calculated. During exposure, positive changes in the lipid profile that included a decrease in the TCh, initiated after the 20th WBC session with a simultaneous decrease in TG and LDL levels, and an increase in the HDL concentration were observed. These changes were accompanied by a downward trend in the ApoB concentration and a decrease in the ApoB:ApoA-I ratio after 30 sessions. The nature of these changes persisted for a month after the exposure. The obtained results indicate metabolic benefits that result from prolonged exposure to cryogenic temperatures, confirming the postulate of using WBC in the regulation of lipid metabolism and the prevention of cardiovascular diseases.


Assuntos
LDL-Colesterol/sangue , Crioterapia/métodos , Proteínas de Choque Térmico HSP70/sangue , Metabolismo dos Lipídeos/fisiologia , Triglicerídeos/sangue , Biomarcadores/sangue , Crioterapia/tendências , Voluntários Saudáveis , Humanos , Masculino , Distribuição Aleatória , Adulto Jovem
2.
Exp Clin Endocrinol Diabetes ; 125(3): 176-182, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27898988

RESUMO

Lipid accumulation product (LAP) is an index used for evaluating lipid overaccumulation in adults. Our study aimed at assessing associations between LAP and metabolic syndrome (MetS) and its components, age-related testosterone deficiency syndrome (TDS), low-density cholesterol (LDL), as well as HOMA-IR (insulin resistance ratio), insulin level in non-diabetics and total testosterone (TT), estradiol E2, dehydroepiandrosterone sulphate (DHEAs) and sex hormone-binding globulin (SHBG) in aging men.313 men aged 50-75 were surveyed with regard to the prevalence of diabetes (T2DM) and hypertension (HT). Anthropometric measurements, including waist circumference and arterial pressure, were performed. We also determined the levels of fasting plasma glucose (FPG), total cholesterol (TC), high-density cholesterol (HDL), low-density cholesterol (LDL), triglyceride (TG), insulin, TT, SHBG, DHEAs, and E2.Patients with diagnosed MetS, T2DM, HT, obesity, overweight and TDS had a significantly higher LAP compared to those without these conditions. LAP was significantly positively correlated with serum TC, FPG, insulin, DHEAs, as well as APB-systolic concentration, and negatively correlated with HDL, TT, and SHBG.LAP may then be used as a simple and inexpensive biomarker of metabolic disorders, and in risk assessment related to testosterone deficiency in aging men.


Assuntos
Envelhecimento/sangue , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Hipertensão/sangue , Produto da Acumulação Lipídica , Lipídeos/sangue , Testosterona/sangue , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Circunferência da Cintura
3.
Exp Parasitol ; 169: 69-76, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27466058

RESUMO

The aim of this study was to determine whether Hymenolepis diminuta may affect the expression and activity of cyclooxygenase 1 (COX-1) and cyclooxygenase 2 (COX-2), resulting in the altered levels of their main products - prostaglandins (PGE2) and thromboxane B2 (TXB2). The study used the same experimental model as in our previous studies in which we had observed changes in the transepithelial ion transport, tight junctions and in the indicators of oxidative stress, in both small and large intestines of rats infected with H. diminuta. In this paper, we investigated not only the site of immediate presence of the tapeworm (jejunum), but also a distant site (colon). Inflammation related to H. diminuta infection is associated with the increased expression and activation of cyclooxygenase (COX), enzyme responsible for the synthesis of PGE2 and TXB2, local hormones contributing to the enhanced inflammatory reaction in the jejunum and colon in the infected rats. The increased COX expression and activity is probably caused by the increased levels of free radicals and the weakening of the host's antioxidant defense induced by the presence of the parasite. Our immunohistochemical analysis showed that H. diminuta infection affected not only the intensity of the immunodetection of COX but also the enzyme protein localization within intestinal epithelial cells - from the entire cytoplasm to apical/basal regions of cells, or even to the nucleus.


Assuntos
Colo/enzimologia , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Himenolepíase/enzimologia , Hymenolepis diminuta/fisiologia , Jejuno/enzimologia , Animais , Western Blotting , Colo/parasitologia , Dinoprostona/metabolismo , Himenolepíase/parasitologia , Himenolepíase/patologia , Imuno-Histoquímica , Inflamação , Jejuno/parasitologia , Masculino , Ratos , Ratos Wistar , Tromboxano B2/metabolismo , Tribolium
4.
Gesundheitswesen ; 78(11): 749-751, 2016 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-25622211

RESUMO

Introduction: Early menopause may be associated with serious health risks resulting from, for example, decreased oestrogen levels. This may occur despite hormone replacement therapy. Aim: The aim of this study was the determination of the effect of selected reproductive factors and smoking on age at the onset of menopause in women from Szczecin and surrounding areas. Material and Methods: 305 women after natural menopause were asked to complete a questionnaire, and blood samples were collected from them to test for the levels of follicle stimulating hormone (FSH) and oestradiol (E2). Results: Smoking women experienced menopause on average more than a year earlier than non-smokers, but this difference was not statistically significant. There was no statistically significant effect of age at menarche or first birth on age at the last menstrual period. Conclusions: Age at menarche and first birth were not related to age at menopause. In smoking women, menopause occurred earlier but the difference was not statistically significant.


Assuntos
Envelhecimento/sangue , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Menopausa Precoce/sangue , Fumar/sangue , Fumar/epidemiologia , Distribuição por Idade , Feminino , Alemanha/epidemiologia , Humanos , Menopausa/sangue , Pessoa de Meia-Idade , Polônia/epidemiologia , Saúde Reprodutiva/estatística & dados numéricos
5.
Rep Prog Phys ; 78(11): 114001, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26510115

RESUMO

This report on progress explores recent advances in our theoretical and experimental understanding of the physics of open quantum systems (OQSs). The study of such systems represents a core problem in modern physics that has evolved to assume an unprecedented interdisciplinary character. OQSs consist of some localized, microscopic, region that is coupled to an external environment by means of an appropriate interaction. Examples of such systems may be found in numerous areas of physics, including atomic and nuclear physics, photonics, biophysics, and mesoscopic physics. It is the latter area that provides the main focus of this review, an emphasis that is driven by the capacity that exists to subject mesoscopic devices to unprecedented control. We thus provide a detailed discussion of the behavior of mesoscopic devices (and other OQSs) in terms of the projection-operator formalism, according to which the system under study is considered to be comprised of a localized region (Q), embedded into a well-defined environment (P) of scattering wavefunctions (with Q + P = 1). The Q subspace must be treated using the concepts of non-Hermitian physics, and of particular interest here is: the capacity of the environment to mediate a coupling between the different states of Q; the role played by the presence of exceptional points (EPs) in the spectra of OQSs; the influence of EPs on the rigidity of the wavefunction phases, and; the ability of EPs to initiate a dynamical phase transition (DPT). EPs are singular points in the continuum, at which two resonance states coalesce, that is where they exhibit a non-avoided crossing. DPTs occur when the quantum dynamics of the open system causes transitions between non-analytically connected states, as a function of some external control parameter. Much like conventional phase transitions, the behavior of the system on one side of the DPT does not serve as a reliable indicator of that on the other. In addition to discussing experiments on mesoscopic quantum point contacts that provide evidence of the environmentally-mediated coupling of quantum states, we also review manifestations of DPTs in mesoscopic devices and other systems. These experiments include observations of resonance-trapping behavior in microwave cavities and open quantum dots, phase lapses in tunneling through single-electron transistors, and spin swapping in atomic ensembles. Other possible manifestations of this phenomenon are presented, including various superradiant phenomena in low-dimensional semiconductors. From these discussions a generic picture of OQSs emerges in which the environmentally-mediated coupling between different quantum states plays a critical role in governing the system behavior. The ability to control or manipulate this interaction may even lead to new applications in photonics and electronics.

6.
Biotech Histochem ; 89(5): 342-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24325682

RESUMO

Aquaporin 2 (AQP2) is a small, integral tetrameric plasma membrane protein that is expressed in mammalian kidneys. The specific constitution of this protein and its selective permeability to water means that AQP2 plays an important role in hypertonic urine production. Immunolocalization of AQP2 has been studied in humans, monkeys, sheep, dogs, rabbits, rats, mice and adult cattle. We analyzed the expression of AQP2 in kidneys of 7-month-old Polish-Friesian var. black and white male calves. AQP2 was localized in the principal cells of collecting ducts in medullary rays penetrating the renal cortex and in the collecting ducts of renal medulla. AQP2 was expressed most strongly in the apical plasma membrane, but expression was observed also in the intracellular vesicles and basolateral plasma membrane. Our study provides new information concerning the immunolocalization of AQP2 in calf kidneys.


Assuntos
Aquaporina 2/análise , Rim/química , Animais , Bovinos , Imuno-Histoquímica , Rim/ultraestrutura , Masculino
7.
Gesundheitswesen ; 76(3): 169-71, 2014 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-23780860

RESUMO

INTRODUCTION: Underfunding of the health systemin Poland causes the patients to bear a proportion of the costs of treatment. AIM: The aim of this study was to gather knowledge of health-care services financed by the patients and socio-demographic factors which are influencing how often they use them. MATERIAL AND METHODS: A diagnostic survey was conducted among 384 residents of the West Pomeranian Province. RESULTS: Respondents most frequently used the paid services of dental care. CONCLUSIONS: The age and health condition impact on the frequency of using self-paid health-care services. condition impact on the frequency of using self-paid healthcare services.


Assuntos
Orçamentos/estatística & dados numéricos , Assistência Odontológica/economia , Custos de Cuidados de Saúde/estatística & dados numéricos , Prática Privada/economia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Assistência Odontológica/estatística & dados numéricos , Características da Família , Feminino , Serviços de Saúde/economia , Serviços de Saúde/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Polônia , Vigilância da População , Prática Privada/estatística & dados numéricos , Distribuição por Sexo , Fatores Socioeconômicos , Revisão da Utilização de Recursos de Saúde , Adulto Jovem
8.
Gesundheitswesen ; 75(8-9): 500-2, 2013 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-23299575

RESUMO

AIM: The aim of this work is to assess the impact of replacement therapy on social and professional re-adaptation of people addicted to opioids. MATERIAL AND METHODS: This study covered 82 patients (52 male, 30 female; mean age of 39.9 years) addicted to opioids and treated with methadone. An analysis of medical records served as a research method. RESULTS: Participation in the methadone programme influenced taking up a job by 47.5% of addicted; improving the legal situation, i. e., reduction of the number of criminal cases for 42.7% of addicted; and the feeling of positive impact on social re-adaptation by 96.3% of addicted. CONCLUSIONS: Replacement therapy with methadone fosters professional activation, reduces criminality and gives a feeling of social re-adaptation for people addicted to opioids.


Assuntos
Crime/estatística & dados numéricos , Emprego/estatística & dados numéricos , Metadona/uso terapêutico , Tratamento de Substituição de Opiáceos/métodos , Tratamento de Substituição de Opiáceos/estatística & dados numéricos , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Transtornos Relacionados ao Uso de Opioides/terapia , Adulto , Analgésicos Opioides/uso terapêutico , Crime/prevenção & controle , Feminino , Humanos , Masculino , Polônia/epidemiologia , Prevalência , Fatores de Risco , Ajustamento Social , Isolamento Social , Fatores Socioeconômicos , Resultado do Tratamento
9.
Phys Rev E Stat Nonlin Soft Matter Phys ; 71(3 Pt 2A): 036227, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15903566

RESUMO

We study the spectrum of an open double quantum dot as a function of different system parameters in order to receive information on the geometric phases of branch points in the complex plane (BPCP). We relate them to the geometrical phases of the diabolic points (DPs) of the corresponding closed system. The double dot consists of two single dots and a wire connecting them. The two dots and the wire are represented by only a single state each. The spectroscopic values follow from the eigenvalues and eigenfunctions of the Hamiltonian describing the double dot system. They are real when the system is closed, and complex when the system is opened by attaching leads to it. The discrete states as well as the narrow resonance states avoid crossing. The DPs are points within the avoided level crossing scenario of discrete states. At the BPCP, width bifurcation occurs. Here, different Riemann sheets evolve and the levels do not cross anymore. The BPCP are physically meaningful. The DPs are unfolded into two BPCP with different chirality when the system is opened. The geometric phase that arises by encircling the DP in the real plane, is different from the phase that appears by encircling the BPCP. This is found to be true even for a weakly opened system and the two BPCP into which the DP is unfolded.

10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 71(4 Pt 2): 046204, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15903767

RESUMO

By using a simple model we consider single-channel transmission through a double quantum dot that consists of two single dots coupled by a wire of finite length L . Each of the two single dots is characterized by a few energy levels only, and the wire is assumed to have only one level whose energy depends on the length L . The transmission is described by using S matrix theory and the effective non-Hermitian Hamilton operator H(eff) of the system. The decay widths of the eigenstates of H(eff) depend strongly on energy. The model explains the origin of the transmission zeros of the double dot that is considered by us. Mostly, they are caused by (destructive) interferences between neighboring levels and are of first order. When, however, both single dots are identical and their transmission zeros are of first order, those of the double dot are of second order. First-order transmission zeros cause phase jumps of the transmission amplitude by pi, while there are no phase jumps related to second-order transmission zeros. In this latter case, a phase jump occurs due to the fact that the width of one of the states vanishes when crossing the energy of the transmission zero. The parameter dependence of the widths of the resonance states is determined by the spectral properties of the two single dots.

11.
Phys Rev E Stat Nonlin Soft Matter Phys ; 69(6 Pt 2): 066201, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15244702

RESUMO

We consider single-channel transmission through a double quantum dot system consisting of two single dots that are connected by a wire and coupled each to one lead. The system is described in the framework of the S matrix theory by using the effective Hamiltonian of the open quantum system. It consists of the Hamiltonian of the closed system (without attached leads) and a term that accounts for the coupling of the states via the continuum of propagating modes in the leads. This model allows one to study the physical meaning of branch points in the complex plane. They are points of coalesced eigenvalues and separate the two scenarios with avoided level crossings and without any crossings in the complex plane. They influence strongly the features of transmission through double quantum dots.

12.
Phys Rev E Stat Nonlin Soft Matter Phys ; 68(1 Pt 2): 016211, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12935229

RESUMO

The properties of open quantum systems are described well by an effective Hamiltonian H that consists of two parts: the Hamiltonian H of the closed system with discrete eigenstates and the coupling matrix W between discrete states and continuum. The eigenvalues of H determine the poles of the S matrix. The coupling matrix elements W(cc')(k) between the eigenstates k of H and the continuum may be very different from the coupling matrix elements W(cc')(k) between the eigenstates of H and the continuum. Due to the unitarity of the S matrix, the W(cc')(k) depend on energy in a nontrivial manner. This conflicts with the assumptions of some approaches to reactions in the overlapping regime. Explicit expressions for the wave functions of the resonance states and for their phases in the neighborhood of, respectively, avoided level crossings in the complex plane and double poles of the S matrix are given.

13.
Phys Rev E Stat Nonlin Soft Matter Phys ; 67(2 Pt 2): 026204, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12636773

RESUMO

Exceptional points and double poles of the S matrix are both characterized by the coalescence of a pair of eigenvalues. In the first case, the coalescence causes a defect of the Hilbert space. In the second case, this is not so as shown in previous papers. Mathematically, the reason for this difference is the biorthogonality of the eigenfunctions of a non-Hermitian operator that is ignored in the first case. The consequences for the topological structure of the Hilbert space are studied and compared with existing experimental data.

14.
Phys Rev E Stat Nonlin Soft Matter Phys ; 65(6 Pt 2): 066211, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12188819

RESUMO

In a recent work the resonance widths in a microwave billiard with attached waveguide were studied in dependence on the coupling strength [E. Persson et al., Phys. Rev. Lett. 85, 2478 (2000)], and resonance trapping was experimentally found. In the present paper an effective Hamiltonian is derived that depends exclusively on billiard and waveguide geometry. Its eigenvalues give the poles of the scattering matrix provided that the system and environment are defined adequately. Further, we present the results of resonance trapping measurements where, in addition to our previous work, the position of the slit aperture within the waveguide was varied. Numerical simulations with the derived Hamiltonian qualitatively reproduce the experimental data.

15.
Phys Rev E Stat Nonlin Soft Matter Phys ; 65(2 Pt 2): 026217, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11863642

RESUMO

Laser-induced degenerate states (LIDS) are equivalent to double poles of the S matrix that are branch points in the complex plane (BPCP). These branch points cause geometric phase changes by encircling them adiabatically around a closed circuit by varying certain parameters. They cause also the well-known phase changes appearing by encircling a diabolic point (DP) being a singularity associated with level repulsion. In both cases, the wave functions are exchanged, Phi(i) --> +/- iPhi(j not equal i), at the critical value of the parameter where the states avoid crossing. Such a critical point is passed twice by encircling a DP but only once by surrounding a BPCP. As a consequence, the phase changes are different in both cases. A second surrounding restores the wave functions including their phases in both cases (when the BPCP is well isolated from others and the time of encircling is shorter than the lifetime of the two states). The different interference pictures appearing in surrounding LIDS adiabatically in opposite directions on a closed circuit represent a completion of the work by Berry.

16.
Phys Rev E Stat Nonlin Soft Matter Phys ; 64(5 Pt 2): 056214, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11736061

RESUMO

The poles of the S matrix and the wave functions of open two-dimensional quantum billiards with convex boundary of different shape are calculated by using the method of complex scaling. Two leads are attached to the cavities. The conductance of the cavities is calculated at energies with one, two, and three open channels in each lead. Bands of overlapping resonance states appear that are localized along the convex boundary of the cavities and contribute coherently to the conductance. These bands correspond to the whispering gallery modes known from classical calculations.

17.
Phys Rev E Stat Nonlin Soft Matter Phys ; 64(3 Pt 2): 036213, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11580428

RESUMO

A relation between the eigenvalues of an effective Hamilton operator and the poles of the S matrix is derived that holds for isolated as well as for overlapping resonance states. The system may be a many-particle quantum system with two-body forces between the constituents or it may be a quantum billiard without any two-body forces. Avoided crossings of discrete states as well as of resonance states are traced back to the existence of branch points in the complex plane. Under certain conditions, these branch points appear as double poles of the S matrix. They influence the dynamics of open as well as of closed quantum systems. The dynamics of the two-level system is studied in detail analytically as well as numerically.

18.
Artigo em Inglês | MEDLINE | ID: mdl-11088480

RESUMO

The Hamiltonian H of an open quantum system is non-Hermitian. Its complex eigenvalues E(R) are the poles of the S matrix and provide both the energies and widths of the states. We illustrate the interplay between Re(H) and Im(H) by means of the different interference phenomena between two neighboring resonance states. Level repulsion may occur along the real or imaginary axis (the latter is called resonance trapping). In any case, the eigenvalues of the two states avoid crossing in the complex plane. We then calculate the poles of the S matrix and the corresponding wave functions for a rectangular microwave resonator with a scatter as a function of the area of the resonator as well as of the degree of opening to a waveguide. The calculations are performed by using the method of exterior complex scaling. Re(H) and Im(H) cause changes in the structure of the wave functions which are permanent, as a rule. The resonance picture obtained from the microwave resonator shows all the characteristic features known from the study of many-body systems in spite of the absence of two-body forces. The effects arising from the interplay between resonance trapping and level repulsion along the real axis are not involved in the statistical theory (random matrix theory).

19.
Artigo em Inglês | MEDLINE | ID: mdl-11046240

RESUMO

Numerical calculations for a microwave Sinai billiard coupled strongly to a lead are performed as a function of the coupling strength between billiard and lead. They prove the formation of different time scales in an open quantum system at large coupling strength. The short-lived collective states are formed together with many long-lived trapped states.

20.
Phys Rev Lett ; 85(12): 2478-81, 2000 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-10978086

RESUMO

The coupling of a quantum mechanical system to open decay channels has been theoretically studied in numerous works, mainly in the context of nuclear physics but also in atomic, molecular, and mesoscopic physics. Theory predicts that with increasing coupling strength to the channels the resonance widths of all states should first increase but finally decrease again for most of the states. In this Letter, the first direct experimental verification of this effect, known as resonance trapping, is presented. In the experiment a microwave Sinai cavity with an attached waveguide with variable slit width was used.

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