Changes in somatosensory evoked potentials in rats following transient cerebral ischemia

Background. Cerebral ischemia induced by transient middle cerebral artery occlusion is one of the most popular ischemic stroke models used to evaluate drug candidates with neuroprotective properties. The possibilities of combining this model with neurophysiological techniques (e.g., electroencephalography, electrocorticography, evoked potential registration, etc.) to assess the effectiveness of novel pharmacotherapeutic strategies appear to be of great interest to current biomedical research.The aim. Identifying specific changes in somatosensory evoked potentials occurring after cerebral ischemia induced by middle cerebral artery occlusion in rats.Materials and methods. A total number of 18 white outbred male rats were randomized into 3 groups by 6 animals in each: 1) control (presumably healthy animals); 2) ischemia-30 (30-minute middle cerebral artery occlusion); 3) ischemia-45 (45-minute occlusion). At post-surgery day 7, cortical responses to sequential electrical stimulation of left and right n. ischiadicus were registered. N1, P2, N2, P3, and N3 peak latencies and amplitudes, peak-to-peak interval durations and amplitudes were calculated. Spearman’s rank correlation coefficients were used to assess the relationship between ischemia duration and evoked potential parameters, and the Chaddock scale was used to qualitatively evaluate the strength of correlations.Results. The rats subjected to cerebral ischemia demonstrated a decrease in some of the peak amplitudes of the ipsi- and contralateral somatosensory potentials evoked by n. ischiadicus stimulation. In the injured hemisphere, decreased P2 and N3 peak and P3–N3 interval amplitudes were registered ipsilaterally, and decreased P3 peak amplitudes and N2–P3 interval durations were observed contralaterally.Conclusions. The obtained data suggest that somatosensory evoked potential registration and analysis can be used to evaluate the functional state of central nerve tracts in rats subjected to cerebral ischemia

Клинические и иммуноморфологические предикторы неблагоприятного течения хронического гепатита С

Wide incidence and high rate of poor outcomes of viral hepatitis C makes this issue very important. In majority of cases viral hepatitis C develops chronic form of the disease resulting in fibrosis, cirrhosis and hepatocellular carcinoma in longstanding period of time. The specificity of clinical presentation and particular aspects of pathogenesis complicates making the prognosis of its course significantly.Objective. Estimation of clinical and immunomorphological factors that influence the process of fibrogenesis in chronic hepatitis C.Material and methods. The object of our research was 64 liver biopsy samples from adults with natural course of chronic hepatitis C. Using immunohistochemistry and morphometric method intrahepatic CD3+, CD8+Т-lymphocites, CD68+-macrophages, alfa-SMA+-stellate cells were counted. Then the connection between this markers and histological activity index (HAI), stage of fibrosis, ALT elevation, viral load and viral genotype were evaluated.Results. It was established, that increasing amount of intrahepatic CD8+-lymphocytes implicates augmentation of histological activity and ALT level: CD8 abs./HAI – r=0,56; CD8 abs/ALT – r=0,45; HAI/ALT – r=0,58 (p<0,05), and also raising of CD68+-macrophages in mild and moderate HAI: СD8 абс./СD68 абс. – r=0,58 и 0,54 accordingly (p<0,05), and alfa-SMA+-stellate cells. Histological activity was prone to raise with the stage of fibrosis. Also the higher number of intrahepatic CD8+-lymphocytes, HAI and ALT elevation was identified in cases with viral genotype 3.Conclusion. As a result, unfavorable implication of cellrelated  immune lesion and viral genotype 3 in fibrosis progression was  demonstrated. The role of viral load was ambiguous. Актуальность изучения вирусного гепатита С обусловлена его широкой распространенностью и высокой частотой неблагоприятных исходов. Вирусный гепатит С в большинстве случаев протекает в хронической форме, приводя с течением длительного времени к фиброзу, циррозу и гепатоцеллюлярному раку. Характер клинических изменений и особенности патогенеза хронического гепатита С существенно затрудняют  прогнозирование его течения.Цель: определение клинических и иммуноморфологических факторов, оказывающих влияние на процесс фиброгенеза при хроническом гепатите С.Материалы и методы. Объектом нашего исследования явились 64 биоптата печени от взрослых пациентов, переносящих естественное течение ХГС. С помощью иммуноморфологического и морфометрического методов осуществлялся подсчет внутрипеченочных CD3+, CD8+ Т-лимфоцитов, CD68+-макрофагов, alfaSMA+-звездчатых клеток. Оценивалась взаимосвязь показателей с выраженностью гистологической активности, степенью фиброза, выраженностью цитолиза (АЛТ), вирусной нагрузкой и генотипом вируса.Результаты. Установлено, что увеличение содержания внутрипеченочных CD8+- лимфоцитов влечет за собой увеличение гистологической активности и выраженности цитолитического синдрома: CD8 абс./ИГА – r=0,56; CD8 абс./АлАт – r=0,45; ИГА/АлАт – r=0,58 при p<0,05, а также увеличение популяции CD68+ макрофагов при слабой и умеренной гистологической активности: СD8 абс./СD68 абс. – r=0,58 и 0,54 соответственно при p<0,05 и alfa-SMA+ звездчатых клеток, а гистологическая активность гепатита имеет тенденцию к нарастанию по мере увеличения степени фиброза печени. Выявлено достоверно более высокое содержание внутрипеченочных CD8+лимфоцитов, более высокая гистологическая активность и выраженность цитолитического синдрома у пациентов, инфицированных 3 генотипом ВГС.Заключение. Таким образом, была установлена неблагоприятная роль клеточно-опосредованного иммунного повреждения и 3 генотипа вируса в прогрессии фиброза. Значение вирусной нагрузки оказалось неоднозначным

Large enhancement of deuteron polarization with frequency modulated microwaves

We report a large enhancement of 1.7 in deuteron polarization up to values of 0.6 due to frequency modulation of the polarizing microwaves in a two liters polarized target using the method of dynamic nuclear polarization. This target was used during a deep inelastic polarized muon-deuteron scattering experiment at CERN. Measurements of the electron paramagnetic resonance absorption spectra show that frequency modulation gives rise to additional microwave absorption in the spectral wings. Although these results are not understood theoretically, they may provide a useful testing ground for the deeper understanding of dynamic nuclear polarization.Comment: 10 pages, including the figures coming in uuencoded compressed tar files in poltar.uu, which also brings cernart.sty and crna12.sty files neede

ЭЛИМИНАЦИЯ HCV-ИНФЕКЦИИ: ИСТОРИЯ С ПРОДОЛЖЕНИЕМ

Chronic hepatitis C remains one of the most important socially significant infections for world health. The use of modern highly effective drugs with direct antiviral action allows to achieve a sustained virological response in patients. At the same time, in a significant number of cases after elimination of HCV infection, the progression of fibrosis continues with the development of its terminal stages and an unfavorable outcome for patients. The article focuses on comorbid pathology, which is a leading factor in this process in patients with chronic hepatitis C who have achieved a sustained virological response and presenting a serious challenge to modern hepatology.Хронический гепатит С остается одной из актуальных для мирового здравоохранения социально значимых инфекций. Использование современных высокоэффективных препаратов с прямым противовирусным действием позволяет достичь устойчивого вирусологического ответа у пациентов. В то же время в значительном количестве случаев после элиминации HCVинфекции продолжается прогрессирование фиброза с развитием его терминальных стадий и неблагоприятного исхода для пациентов. В настоящей статье обсуждается роль коморбидной патологии, являющейся ведущим фактором в этом процессе у пациентов с хроническим гепатитом С, достигших устойчивого вирусологического ответа, и представляющей серьезный вызов для современной гепатологии

Spin Structure of the Proton from Polarized Inclusive Deep-Inelastic Muon-Proton Scattering

We have measured the spin-dependent structure function $g_1^p$ in inclusive deep-inelastic scattering of polarized muons off polarized protons, in the kinematic range $0.003 < x < 0.7$ and $1 GeV^2 < Q^2 < 60 GeV^2$. A next-to-leading order QCD analysis is used to evolve the measured $g_1^p(x,Q^2)$ to a fixed $Q^2_0$. The first moment of $g_1^p$ at $Q^2_0 = 10 GeV^2$ is $\Gamma^p = 0.136\pm 0.013(stat.) \pm 0.009(syst.)\pm 0.005(evol.)$. This result is below the prediction of the Ellis-Jaffe sum rule by more than two standard deviations. The singlet axial charge $a_0$ is found to be $0.28 \pm 0.16$. In the Adler-Bardeen factorization scheme, $\Delta g \simeq 2$ is required to bring $\Delta \Sigma$ in agreement with the Quark-Parton Model. A combined analysis of all available proton and deuteron data confirms the Bjorken sum rule.Comment: 33 pages, 22 figures, uses ReVTex and smc.sty. submitted to Physical Review

Polarised quark distributions in the nucleon from semi-inclusive spin asymmetries

We present a measurement of semi-inclusive spin asymmetries for positively and negatively charged hadrons from deep inelastic scattering of polarised muons on polarised protons and deuterons in the range $0.003$1~GeV$^2$. Compared to our previous publication on this subject, with the new data the statistical errors have been reduced by nearly a factor of two. From these asymmetries and our inclusive spin asymmetries we determine the polarised quark distributions of valence quarks and non-strange sea quarks at $Q^2$=10~GeV$^2$. The polarised $u$ valence quark distribution, $\Delta u_v(x)$, is positive and the polarisation increases with $x$. The polarised $d$ valence quark distribution, $\Delta d_v(x)$, is negative and the non-strange sea distribution, $\Delta \bar q(x)$, is consistent with zero over the measured range of $x$. We find for the first moments $\int_0^1 \Delta u_v(x) {\rm d}x = 0.77 \pm 0.10 \pm 0.08$, $\int_0^1 \Delta d_v(x) {\rm d}x = -0.52 \pm 0.14 \pm 0.09$ and $\int_0^1 \Delta \bar q(x) {\rm d}x= 0.01 \pm 0.04 \pm 0.03$, where we assumed $\Delta \bar u(x) = \Delta \bar d(x)$. We also determine for the first time the second moments of the valence distributions $\int_0^1 x \Delta q_v(x) {\rm d}x$.We present a measurement of semi-inclusive spin asymmetries for positively and negatively charged hadrons from deep inelastic scattering of polarised muons on polarised protons and deuterons in the range $0.003$1 GeV$^2$. Compared to our previous publication on this subject, with the new data the statistical errors have been reduced by nearly a factor of two. From these asymmetries and our inclusive spin asymmetries we determine the polarised quark distributions of valence quarks and non-strange sea quarks at $Q^2$=10 GeV$^2$. The polarised $u$ valence quark distribution, $\Delta u_v(x)$, is positive and the polarisation increases with $x$. The polarised $d$ valence quark distribution, $\Delta d_v(x)$, is negative and the non-strange sea distribution, $\Delta \bar q(x)$, is consistent with zero over the measured range of $x$. We find for the first moments $\int_0^1 \Delta u_v(x) dx = 0.77 \pm 0.10 \pm 0.08$, $\int_0^1 \Delta d_v(x) dx = -0.52 \pm 0.14 \pm 0.09$ and $\int_0^1 \Delta \bar q(x) dx= 0.01 \pm 0.04 \pm 0.03$, where we assumed $\Delta \bar u(x) = \Delta \bar d(x)$. We also determine for the first time the second moments of the valence distributions $\int_0^1 x \Delta q_v(x) dx$.We present a measurement of semi-inclusive spin asymmetries for positively and negatively charged hadrons from deep inelastic scattering of polarised muons on polarised protons and deuterons in the range $0.003$1 GeV$^2$. Compared to our previous publication on this subject, with the new data the statistical errors have been reduced by nearly a factor of two. From these asymmetries and our inclusive spin asymmetries we determine the polarised quark distributions of valence quarks and non-strange sea quarks at $Q^2$=10 GeV$^2$. The polarised $u$ valence quark distribution, $\Delta u_v(x)$, is positive and the polarisation increases with $x$. The polarised $d$ valence quark distribution, $\Delta d_v(x)$, is negative and the non-strange sea distribution, $\Delta \bar q(x)$, is consistent with zero over the measured range of $x$. We find for the first moments $\int_0^1 \Delta u_v(x) dx = 0.77 \pm 0.10 \pm 0.08$, $\int_0^1 \Delta d_v(x) dx = -0.52 \pm 0.14 \pm 0.09$ and $\int_0^1 \Delta \bar q(x) dx= 0.01 \pm 0.04 \pm 0.03$, where we assumed $\Delta \bar u(x) = \Delta \bar d(x)$. We also determine for the first time the second moments of the valence distributions $\int_0^1 x \Delta q_v(x) dx$.We present a measurement of semi-inclusive spin asymmetries for positively and negatively charged hadrons from deep inelastic scattering of polarised muons on polarised protons and deuterons in the range $0.003$1 GeV$^2$. Compared to our previous publication on this subject, with the new data the statistical errors have been reduced by nearly a factor of two. From these asymmetries and our inclusive spin asymmetries we determine the polarised quark distributions of valence quarks and non-strange sea quarks at $Q^2$=10 GeV$^2$. The polarised $u$ valence quark distribution, $\Delta u_v(x)$, is positive and the polarisation increases with $x$. The polarised $d$ valence quark distribution, $\Delta d_v(x)$, is negative and the non-strange sea distribution, $\Delta \bar q(x)$, is consistent with zero over the measured range of $x$. We find for the first moments $\int_0^1 \Delta u_v(x) dx = 0.77 \pm 0.10 \pm 0.08$, $\int_0^1 \Delta d_v(x) dx = -0.52 \pm 0.14 \pm 0.09$ and $\int_0^1 \Delta \bar q(x) dx= 0.01 \pm 0.04 \pm 0.03$, where we assumed $\Delta \bar u(x) = \Delta \bar d(x)$. We also determine for the first time the second moments of the valence distributions $\int_0^1 x \Delta q_v(x) dx$.We present a measurement of semi-inclusive spin asymmetries for positively and negatively charged hadrons from deep inelastic scattering of polarised muons on polarised protons and deuterons in the range $0.003$1 GeV$^2$. Compared to our previous publication on this subject, with the new data the statistical errors have been reduced by nearly a factor of two. From these asymmetries and our inclusive spin asymmetries we determine the polarised quark distributions of valence quarks and non-strange sea quarks at $Q^2$=10 GeV$^2$. The polarised $u$ valence quark distribution, $\Delta u_v(x)$, is positive and the polarisation increases with $x$. The polarised $d$ valence quark distribution, $\Delta d_v(x)$, is negative and the non-strange sea distribution, $\Delta \bar q(x)$, is consistent with zero over the measured range of $x$. We find for the first moments $\int_0^1 \Delta u_v(x) dx = 0.77 \pm 0.10 \pm 0.08$, $\int_0^1 \Delta d_v(x) dx = -0.52 \pm 0.14 \pm 0.09$ and $\int_0^1 \Delta \bar q(x) dx= 0.01 \pm 0.04 \pm 0.03$, where we assumed $\Delta \bar u(x) = \Delta \bar d(x)$. We also determine for the first time the second moments of the valence distributions $\int_0^1 x \Delta q_v(x) dx$.We present a measurement of semi-inclusive spin asymmetries for positively and negatively charged hadrons from deep inelastic scattering of polarised muons on polarised protons and deuterons in the range 0.0031 GeV 2 . Compared to our previous publication on this subject, with the new data the statistical errors have been reduced by nearly a factor of two. From these asymmetries and our inclusive spin asymmetries we determine the polarised quark distributions of valence quarks and non-strange sea quarks at Q 2 =10 GeV 2 . The polarised u valence quark distribution, Δu v ( x ), is positive and the polarisation increases with x . The polarised d valence quark distribution, Δd v ( x ), is negative and the non-strange sea distribution, Δ q ̄ (x) , is consistent with zero over the measured range of x . We find for the first moments ∫ 0 1 Δu v (x) d x=0.77±0.10±0.08 , ∫ 0 1 Δd v (x) d x=−0.52±0.14±0.09 and ∫ 0 1 Δ q ̄ (x) d x=0.01±0.04±0.03 , where we assumed Δ u ̄ (x)=Δ d ̄ (x) . We also determine for the first time the second moments of the valence distributions ∫ 0 1 xΔq v (x) d x

Measurement of the spin-dependent structure function g1(x) of the proton

Adams D, Adeva B, Arik E, et al. Measurement of the spin-dependent structure function g1(x) of the proton. Phys.Lett. B. 1994;329(2-3):399-406.We have measured the spin-dependent structure function $g_1~p$ of the proton in deep inelastic scattering of polarized muons off polarized protons, in the kinematic range $0.003<x<0.7$ and 1\,\mbox{GeV}~2. Its first moment, $\int_0~1 g_1~p(x) dx$, is found to be 0.136 \pm 0.011\,(\mbox{stat.})\pm 0.011\,(\mbox{syst.}) at Q~2=10\,\mbox{GeV}~2. This value is smaller than the prediction of the Ellis--Jaffe sum rule by two standard deviations, and is consistent with previous measurements. A combined analysis of all available proton, deuteron and neutron data confirms the Bjorken sum rule to within $10\%$ of the theoretical value

Construction, assembly and testing of the ATLAS hadronic end-cap calorimeter

The construction and assembly of the four wheels of the ATLAS hadronic end-cap calorimeter and their insertion into the two end-cap cryostats are described. The results of the qualification tests prior to installation of the two cryostats in the ATLAS experimental cavern are reviewed