Лимонна вербена (ЛВ) використовується в традиційній народній медицині як засіб проти астми, спазмів, застуди, лихоманки, болю різного походження, безсоння і т. п., проте її ефекти не досліджувались експериментально. Вивчали дію водного екстракту листя цієї рослини на параметри тестів, пов'язаних із ноцицепцією, - тесту відсмикування хвоста та тесту "кислотних корчів". Готували перший водний екстракт із листя ЛВ та дегітратували його. Досліди було проведено на 7-ми експериментальних групах щурів лінії Вістар; тварини цих груп одержували внутрішньоочеревинні ін'єкції фізіологічного розчину (контроль), ЛВ-екстракту в 4-х дозах (10, 100, 500 та 1000 мг сухої речовини на 1 кг маси тіла), морфіну та екстракту ЛВ (1000 мг/кг) із попередньою ін'єкцією налоксону. Ін'єкції екстракту в дозах 500 та 1000 мг/кг призводили до суттєвого збільшення латентного періоду реакції відсмикування хвоста у порівнянні з аналогічним показником у контролі (P << 0,001). Кількість "корчів" у відповідному тесті протягом 1 год суттєво зменшувалася після ін'єкцій екстракту в дозах від 100 до 1000 мг/кг. Максимальні аналгетичні ефекти були близькими до таких після ін'єкцій морфіну (10 мг/кг). Налоксон повністю усував ефекти екстракту ЛВ у тесті відсмикування хвоста, але лише частково пригнічував відповідну дію в тесті "корчів". Отже, результати проведених експериментів показали, що водний екстракт листя ЛВ має відчутну антиноцицептивну дію; можливості застосування цього екстракту або його похідних у контролі болю мають бути досліджені в подальшому.

We search for marginal Fermi-liquid behavior in the two-band Hubbard model with one narrow band. We consider the limit of low electron densities in the bands and strong intraband and interband Hubbard interactions. We analyze the influence of electron - polaron effect and other mechanisms of mass-enhancement (related to momentum dependence of the self-energies) on effective mass and scattering times of light and heavy components in the clean case (electron - electron scattering and no impurities). We find the tendency towards phase-separation (towards negative partial compressibility of heavy particles) in a 3D case for large mismatch between the densities of heavy and light bands in a strong coupling limit. We also observe that for low temperatures and equal densities the resistivity in a homogeneous state R(T) ~ T<^>2 behaves in a Fermi-liquid fashion both in 3D and 2D cases. For temperatures higher then effective bandwidth for heavy electrons <$E T~>>~W sub h sup *> the coherent behavior of heavy component is totally destroyed. The heavy particles move diffusively in the surrounding of light particles. In the same time the light particles scatter on the heavy ones as if on immobile (static) impurities. In this regime the heavy component is marginal, while the light one is not. The resistivity goes on saturation for <$E T~>>~W sub h sup *> in the 3D case. In 2D the resistivity has a maximum and localization tail due to weak-localization corrections of Altshuler - Aronov type. Such behavior of resistivity in 3D could be relevant for some uranium-based heavy-fermion compounds like UNi2Al3

and in 2D for some other mixed-valence compounds possibly including the layered manganites. We also consider briefly the superconductive (SC) instability in the model. The leading instability is towards p-wave pairing and is governed by enhanced Kohn - Luttinger mechanism of SC at low electron density. The critical temperature corresponds to the pairing of heavy electrons via polarization of the light ones in 2D.

Індекс рубрикатора НБУВ: В317.23 + В317.242

Рубрики:

Квантова статистика

Теорія фазових переходів 2 роду

Шифр НБУВ: Ж14063 Пошук видання у каталогах НБУВ 
Повний текст  Наукова періодика України 

Aim - to investigate the influence of exogenous lactoferrin (LF) on tumor growth, energy and lipid metabolism of Walker-256 carcinosarcoma and to assess genotoxic effects of LF. The study was performed on Walker-256 tumor-bearing rats. Total lipids and phospholipids were determined by thin-layer chromatography. Comet assay was used to investigate the genotoxic effects of LF. Daily i.p. administrations of exogenous LF at concentrations of 1 mg/kg and 10 mg/kg starting from the 4<^>th day after tumor transplantation suppressed growth of Walker-256 carcinosarcoma by almost 44 %. After treatment with recombinant LF in both doses, the phospholipid composition of Walker-256 carcinosarcoma cells was changed (3-fold increase of phosphatidylethanolamine, 3.4-fold increase of phosphatidylcholine, and 1.8-fold increase of sphingomyelin, while the cardiolipin content decreased by 67 %. Exogenous LF was not genotoxic for bone marrow cells (as assessed by the ratio of PCE/NCE, number of micronuclei) and peripheral blood lymphocytes (percentage of DNA in the tail of a comet) in Walker-256 carcinosarcoma-bearing rats. Conclusion: exogenous LF caused the inhibition of Walker-256 carcinosarcoma growth and a decrease in the microviscosity of plasma cell membranes, and exerted no genotoxicity toward bone marrow cells and peripheral blood of experimental animals.

The effects of long-term administration of phytoestrogens (PEs), genistein (Gen) and naringenin (Nar), on nociception, imflammatory hyperalgesia, and metamizol-induced analgesia, the efficacy of PEs vs 17<$E beta>-E to modulate nociception, as well as the gender dependency of PE effects, and NOS and TH (NO synthase and tyrosine hydroxylase, respectively) expression in the periaqueductal gray (PAG) were studied in gonadectomized female and male rats. The paw pressure, tail flick, and hot plate tests, incapacitance test, and plethismometry were employed for in vivo studies. For in vitro studies, immuno- or histochemical staining of NOS and TH expression in PAG were applied. Data revealed that PEs like 17<$E beta>-E dicreased nociceptive thresholds in both sexes, but more significantly in the female rats. Genistein intensified carrageenan-induced exudative inflammatory reaction and modulated metamizol-induced analgesia. The long-term PE administration resulted in gender-specific alterations of NO and TH expression. The effects of PEs might correlate to gender-specific 17<$E beta>-E-like action in male and female individuals. The results suggest that, similarly to other estrogen-like compounds, PEs can play a significant role in the individualization of analgesic therapy.

Aim - to study upstream and downstream events in CD150-mediated Akt signaling pathway in normal human B cells, EBVtransformed lymphoblastoid (LCL) and malignant Hodgkin's lymphoma (HL) B cell lines. Methods: to access protein-protein interaction we applied immunoprecipitation, Western blot analysis and surface plasmon resonance (SPR) technique. A novel modification of SPR technique using reduced glutathione bound to golden surface was proposed. Immunostaining and isolation of cytoplasmic fractions and nuclear extracts were performed to detect proteins' localization in cells. Western blot analysis was performed to follow up the phosphorylation of proteins on specific sites and proteins' expression level. It was shown that CD150 ligation induced Akt activation in normal tonsillar B cells (TBC), SH2D1A positive LCL and HL B cell lines. The p85alpha subunit of PI3K co-precipitated with CD150 cytoplasmic tail. This direct association depends on tyrosine phosphorylation and is mediated by N terminal SH2 domain of p85alpha. CD150 initiated phosphorylation of FoxO1 transcription factor in normal B cells as well as in LCL MP-1 and HL cell line L1236. At the same time, CD150 ligation triggered GSK-3beta kinase phosphorylation only in immortalized LCL MP-1 and HL cell line L1236. Conclusions: we have demonstrated that CD150 receptor could trigger PI3K-mediated Akt signaling pathway in normal, EBV-transformed and malignant B cells. CD150-mediated phosphorylation of Akt downstream targets GSK-3beta and FoxO1 in EBV-transformed and HL cells could be one of the mechanisms to avoid apoptosis and support survival program in these immortalized B cells.

A computer model to simulate hybrid solar cells based on hydrogenated amorphous silicon carbide (a-SiC:H) and crystalline silicon (c-Si) was developed. Using the developed approach, the current-voltage characteristics of p(n) a-SiC:H/n(p) c-Si heterojunction solar cells were analyzed. It was shown that the maximum cell efficiency of the p - n and n - p tandems is observed for the amorphous layer thickness ~ 0,03 - 0,06 and 0,01 - 0,03 <$E mu>m, respectively. The efficiency of the n - p heterojunctions is found to be higher than that of the p - n tandem by approximately 1,5 %. This is attributed to the fact that, in n-doped a-SiC:H, the conductive band tail is narrower compared to the valence band one in p-doped films. The simulated results are compared with the available experimental data obtained with a-SiC:H/c-Si heterostructures.

The aim of present study was to develop a model for a functional analysis of a recently identified marker of the ovarian cancer - sodium-dependent phosphate transporter NaPi2b. For this purpose, we have created HEK293 stable cell lines expressing wild type or mutant forms of NaPi2b (T330V substitution in a large extracellular loop and a 6 amino acid residues deletion in the C-terminal cytoplasmic tail), revealed in the ovarian cancer cell lines. The expression of wild type and mutant forms NaPi2b in the stable cell lines created was confirmed by Western-blot analysis with monoclonal antibodies against NaPi2b. The cellular models described here will be useful for studying the function of sodium-dependent phosphate transporter NaPi2b in health and disease.

The model-independent part of the radiative corrections, due to the hard-photon emission from the lepton vertex in the elastic electron-deuteron scattering (the so-called elastic radiative tail), has been calculated to the deep inelastic scattering of the electron beam on the deuteron target. The elastic radiative tail has been calculated both for the unpolarized scattering and for the scattering of unpolarized electron beam on the tensor polarized deuteron target.

To date, genome instability is considered to be a common feature not only of tumor cells, but also of non-malignant cells of cancer patients, including peripheral blood lymphocytes (PBLs). The issue of the association between genome instability in tumor cells and PBLs, as well as of its relationship with tumor progression remains poorly understood. Aim - to evaluate the level DNA damage in tumor cells and PBLs of endometrial cancer (EC) patients with regard to clinical and morphological characteristics of the patients. DNA damage was assessed in 106 PBLs samples and 42 samples of tumor cell suspension from EC patients by comet assay. PBLs from 30 healthy women were used as control. The level of DNA damage was expressed as the percentage of DNA in the comet tails (% tail DNA). Results: it was revealed that the amount of DNA damage in PBLs of EC patients was 2,2 times higher in comparison with that of healthy donors (8,3 +- 0,7 and 3,7 +- 0,4 % tail DNA, respectively) (p << 0,05). In this study, no association between the levels of DNA damage in endometrial tumor cells and PBLs was observed (r = 0,11 ; p >> 0,05). The amounts of DNA damage both in tumor cells and PBLs were not related to the degree of tumor differentiation as well as the depth of myometrial invasion, but depended on the body mass index (BMI) of EC patients: high level of lesions was observed in patients with elevated BMI values. Furthermore, the level of DNA damage in tumor cells was associated to familial aggregation of cancer and was significantly higher in endometrial cells from patients with family history of cancer vs that from EC patients with sporadic tumors (32,3 +- 2,9 and 22,8 +- 1,8 % tail DNA, respectively) (p << 0,05). It was also found that for women who had high level of DNA damage in PBLs, the risk of EC was greater (odds ratio value of 3,5) compared to those with low level of such lesions. Conclusion: genome instability that appears as an increased level of DNA damage in tumor cells and PBLs of EC patients is associated with BMI and family history of cancer and can reflect a predisposition to cancer.

Fullerene C60 films were grown using physical vapor deposition on Si substrates at room temperature. Then chemical modification with cross-linking these films was performed using the reaction with 1,8-octanediamine (DA) or octane-1,8-dithiol (DT). These chemically cross-linked C60 films are capable of stable binding the Ag or Au nanoclusters. Optical properties of the obtained nanostructured hybrid films were investigated by both reflectance spectroscopy and spectral ellipsometry within the spectral range 1,55 to 5,0 eV at various angles of incidence. From the spectral dependences of the extinction coefficient in the region of optical absorption edge, the physical nature of the fundamental allowed direct band-gap transitions between HOMO-LUMO states <$E E sub g>, the optical absorption edge near the intrinsic transition <$E E sub o>, and exponential tail of the density-of-states caused by defects have been determined. Influence of chemical modification and decoration of metal nanoparticles on the above mentioned parameters has been analyzed.

Центральное ядро амигдалярного комплекса (Ce) является структурой, в которой заканчивается один из важнейших ноцицептивных путей, спино (тригемино)-парабрахио-амигдалярный тракт. В экспериментах на белых крысах-самцах Ce билатерально электролитически разрушалось. Уровень ноцицепции оценен по значениям латентного периода реакции отдергивания хвоста, которые сравнивали с соответствующими величинами у интактных и псевдооперированных крыс. Стереотаксическая билатеральная электролитическая коагуляция Се существенно снижала болевую чувствительность. Кроме того, изменения болевой чувствительности в пределах дня, характерные для контрольных животных, заметно сглаживались.

Influence of light polarization on absorption saturation for wurtzite modification CdSe has been investigated. It has been ascertained that the size of blurring the fundamental absorption edge for wurtzite modification CdSe is determined by the non-equilibrium electron filling both the conduction band extremum, when the energy of photons <$Eh nu> is higher than the bandgap energy Eg, and the density-of-state tail caused by the presence of static disorder, when the <$Eh nu~<<~E sub g>. The density-of-state tail resulting from the presence of dynamic disorder is not filled with electrons because of continuous changes of the dynamic potential relief value in time. In the high-energy spectral region, change in the absorption coefficient is limited by the stimulated emission processes.

In this article, two factors that limit the performance of HIT solar cells (Heterojunction with Intrinsic Thin Layer) based on amorphous silicon/crystalline silicon are studied. First, we study the influence of the valence band tail width (characteristic energy ED) and the conduction band tail width (characteristic energy ED) of hydrogenated amorphous silicon. Then we analyze the effect of electrons mobility <$Emu>n and holes mobility <$Emu>p in the emitter of the structure ITO/p-a-Si:H/i-pm-Si:H/n-c-Si/Al. Our results show that a decrease of ED in the p-a-Si:H layer decreases the donors density of states in the gap. as well as holes recombination in thus layer. However, no amelioration is observed when ED decreases. Furthermore, we show that increasing the mobility of charge earners pn and <$Emu>p, enhance the performance of the studied solar cells.

Aim - to investigate the mechanisms of cytotoxic activity and pro-/antioxidant effect of lactoferrin on hormone receptor-positive and receptor-negative breast cancer cells in vitro. The study was performed on receptor-positive (MCF-7, T47D) and receptor-negative (MDA-MB-231, MDA-MB-468) human breast cancer cell lines. Immunocytochemical staining, flow cytometry, low-temperature electron paramagnetic resonance, and the Comet assay were used. Upon treatment with lactoferrin, the increased levels of reactive oxygen species (ROS) (p << 0,05), NO generation rate by inducible NO-synthase (p << 0,05) and the level of "free" iron (p << 0,05) were observed. Moreover, the effects of lactoferrin were more pronounced in receptor-negative MDA-MB-231 and MDA-MB-468 cells. These changes resulted in increased expression of proapoptotic Bax protein (p << 0,05), reduced expression of the antiapoptotic Bcl-2 protein (p << 0,05) and level of not-oxidized mitochondrial cardiolipin (1,4 - 1,7-fold, p << 0,05). This, in turn, caused an increase in the percentage of apoptotic cells (by 14 - 24 %, p << 0,05). Cytotoxic effects of lactoferrin were accompanied by an increase in the percentage of DNA in the comet tail and blocking cell cycle at G2/M phase, especially in receptor-negative cell lines. Conclusion: the study showed that exogenous lactoferrin causes a violation of an antioxidant balance by increasing the level of ROS, "free" iron and NO generation rate, resalting in the blocking of cell cycle at G2/M-phase and apoptosis of malignant cells.

We present an explicit water molecular dynamics simulation of dilute solutions of model alkyltrimethylammonium surfactant ions (number of methylene groups in the tail is 3, 5, 8, 10, and 12) in mixture with NaF, NaCl, NaBr, and NaI salts, respectively. The SPC/E model is used to describe water molecules. Results of the simulation at 298 K are presented in the form of radial distribution functions between nitrogen and carbon atoms of CH2 groups on the alkyltrimethylammonium ion, and the counterion species in the solution. The running coordination numbers between carbon atoms of surfactants and counterions are also calculated. We show that I<^>- counterion exhibits the highest, and F<^>- the lowest affinity to "bind" to the model surfactants. The results are discussed in view of the available experimental and simulation data for this and similar solutions.

Background: intraoperative ultrasound examination (IOUS) is indispensable part of modem surgical interventions in tumors of hepatopancreatobiliary zone. In this study retrospective analysis of IOUS efficiency in surgical treatment of pancreatic tumors was provided. In the period from January 2013 till November 2015 in the National Cancer Institute IOUS was applied during 76 surgical interventions: for pancreatic head tumors - in 46 (60,5 %) patients, for body/tail pancreatic tumors - in 20 (26,3 %) patients, in 10 (13,2 %) patients - for periampullary zone neoplasms. In IOUS we performed primary tumor assessment (localization, degree of tumor spreading to superior mesenteric vessels, hepatoduodenal ligament vessels, additional foci occurrence in pancreas), and liver metastases detection. Surgical interventions were performed: pancreatoduodenectomy in 52 (68,4 %) patients, radical antegrade modal pancreatosplenectomy - in 14 (18,4 %) patients. IOUS allowed determining additional tumor foci in pancreas in 2 (2,6 %) patients, in 8 (10,5 %) observations tumor invasion into portal or superior mesenteric vein was determined. In 21 (27,6 %) patient additional hepatic neoplasms were detected (in half of cases - 11,8 %, metastases). These findings resulted in change of surgical intervention extent in 23 (30,3 %) patients: expansion to combined resections in 14 (18,4 %) patients, reduction to symptomatic operations in 5 (6,6 %) cases, organ-preserving operations were performed in 4 (5,3 %) patients. Variant anatomy of hepatic arterial blood supply was determined in 41 (53,9 %) patients that necessitated performance correction of resection stages for preservation of adequate hepatic blood supply. Conclusions: IOUS is a highly-precise diagnostic method substantively influencing operation course in pancreatic tumors, enabling surgeon to provide adequate staging and permanent correction of operation course.

The overdamped Brownian motion of a self-propelled particle which is driven by a projected internal force is studied by solving the Langevin equation analytically. The "active" particle under study is restricted to move along a linear channel. The direction of its internal force is orientationally diffusing on a unit circle in a plane perpendicular to the substrate. An additional time-dependent torque is acting on the internal force orientation. The model is relevant for active particles like catalytically driven Janus particles and bacteria moving on a substrate. Analytical results for the first four time-dependent displacement moments are presented and analysed for several special situations. For a vanishing torque, there is a significant dynamical non-Gaussian behaviour at finite times t as signalled by a non-vanishing normalized kurtosis in the particle displacement which approaches zero for long time with a 1/t long-time tail.

It is shown that systemic injections of analgin and ketorolac in doses equivalent to those used in clinics induce antinociception in awake rats (tail-flick test) and, when carried out repetitively, induce tolerance to these agents and cross-tolerance to morphine (blocked by naloxone).

Організація нервової мережі відсмикування "хвоста" в аплізії дозволяє побудувати модельну систему, за допомогою якої можна ефективно досліджувати прості форми навчання та пам'яті. Використовуючи інтерфейс Python та програмний засіб NEURON, змодельовано даний рефлекс та досліджено декілька властивостей модельної мережі. Феномени адаптації частоти розряду (SFA) та біфуркації з доданням періоду за мінімуму частоти спостережено в сенсорних нейронах за умов стимуляції прямокутними стимулами. В усіх нейронах мережі зміни сили стимуляції призводили спочатку до збільшення числа піків у пачках, а потім до його зменшення. Окрім того, у разі зменшення кількості стимульованих сенсорних нейронів на виходах інтернейронів та моторного нейрона з'являлася підпорогова кайма, що відрізнялася від такої в інтактних пачок. Більш того, потенціали, продуковані моторним нейроном, індукували відповідні осциляції сили, розвинутої м'язовим волокном, що свідчило про сполучення процесів збудження/скорочення у хвостовій частині аплізії. У разі змін провідності синапсів між інтернейронами та мотонейронами тривалість "довгих" імпульсних відповідей закономірно збільшувалася, що вказувало на прояви синаптичної пластичності.

Background - the development of hormone-dependent cancers, including endometrial carcinomas, in great part may be mediated by the genotoxic effects of estrogen metabolites, among which 4-hydroxyestradiol (4OHE2) is characterized by the most prominent DNA-damaging properties. It is assumed that the individual sensitivity to the 4OHE2 may determine the predisposition to endometrial cancer (EС). Aim - to analyze the sensitivity of peripheral blood lymphocytes (PBLs) of EC patients to the 4OHE2 and to evaluate the repair efficiency of 4OHE2-induced DNA damage. The study was performed on the PBLs of 53 EC patients and 20 healthy women. The level of DNA damage was measured using the comet assay and was expressed as % tail DNA. The DNA repair efficiency (%) was evaluated by determining the ratio between the amount of repaired DNA damage and the level of 4OHE2-induced damage that appeared after incubation of PBLs with 4OHE2. In PBLs of EC patients, a higher level of 4OHE2-induced DNA damage (32,0 +- 2,2 % tail DNA) and lower DNA repair efficiency (34,0 +- 4,5 %) was observed compared to PBLs of healthy women (22,3 +- 2,3 % tail DNA and 48,8 +- 4,5 %, respectively). PBLs of EC patients with deep tumor invasion of myometrium were characterized by more prominent decrease of DNA repair than those with less invasive tumor (<< 1/2 of myometrium) (20,9 +- 7,8 and 43,7 +- 6,7 %, respectively). Furthermore, lower DNA repair efficiency was detected in the PBLs of EC patients with a family history of cancer compared to this parameter in patients with sporadic tumors (20,9 +- 7,8 and 47,1 +- 5,5 %, respectively). Conclusion: the PBLs of EC patients are characterized by increased sensitivity to the genotoxic effect of 4OHE2 and reduced repair efficiency regarding 4OHE2-induced DNA damage. A lower level of DNA repair is observed in EC patients with deep tumor myometrial invasion and a family history of cancer.