mV

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Distribution within Medical Sciences

Terms modified by mV

  • mv strain
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  • Selected Abstracts


    C1473G polymorphism in mouse tph2 gene is linked to tryptophan hydroxylase-2 activity in the brain, intermale aggression, and depressive-like behavior in the forced swim test

    JOURNAL OF NEUROSCIENCE RESEARCH, Issue 5 2009
    Daria V. Osipova
    Abstract Tryptophan hydroxylase-2 (TPH2) is the rate-limiting enzyme of brain serotonin synthesis. The C1473G polymorphism in the mouse tryptophan hydroxylase-2 gene affects the enzyme's activity. In the present study, we investigated the linkage between the C1473G polymorphism, enzyme activity in the brain, and behavior in the forced swim, intermale aggression, and open field tests using mice of the C57BL/6 (C/C) and CC57BR/Mv (G/G) strains and the B6-1473C (C/C) and B6-1473G (G/G) lines created by three successive backcrossings on C57BL/6. Mice of the CC57BR/Mv strain had decreased brain enzyme activity, aggression intensity, and immobility in the forced swim test, but increased locomotor activity and time spent in the central part of the open field arena compared with animals of the C57BL/6 strain. Mice of the B6-1473G line homozygous for the 1473G allele had lower TPH2 activity in the brain, aggression intensity, and immobility time in the forced swim test compared with animals of the B6-1473C line homozygous for the 1473C allele. No differences were found between the B6-1473G and B6-1473C mice in locomotor activity and time spent in the central part of the arena in the open field test. Thus, the C1473G polymorphism is involved in the determination of TPH2 activity and is linked to aggression intensity and forced-swim immobility in mice. At the same time, the polymorphism does not affect locomotion and anxiety-related behavior in the open field test. The B6-1473C and B6-1473G mice represent a valuable experimental model for investigating molecular mechanisms of serotonin-related behavior. 2008 Wiley-Liss, Inc. [source]


    Involvement of Transcription Factor HNF3, in the Effect of o -Aminoazotoluene on Glucocorticoid Induction of Tyrosine Aminotransferase in Mice Sensitive to its Hepatocarcinogenic Action

    MOLECULAR CARCINOGENESIS, Issue 1 2001
    Konstantin Y. Kropachev
    Abstract In the rodent liver, hepatocarcinogens inhibit the glucocorticoid induction of several liver-specific genes, including tyrosine aminotransferase (TAT). A distinct positive correlation exists in mice between the extent of inhibition of TAT induction after acute administration of o -aminoazotoluene (OAT) and the frequency of liver tumors after chronic exposure to the carcinogen. To elucidate the mechanism of the carcinogenic action, the effects of OAT on the DNA-binding activity of several transcription factors participating in the glucocorticoid regulation of TAT gene expression were studied. The experimental inbred male mice were sensitive (A/He and SWR/J, tumor induction frequency of 75,100%, TAT induction inhibition of 35,50%) and resistant (CC57BR/Mv and AKR/J, 0,6% and 10,15%, respectively) to OAT. Gel retardation experiments showed that hepatocyte nuclear factor 3 (HNF3), DNA-binding activity was strongly reduced in nuclear extracts from the livers of OAT-treated A/He and SWR/J mice but only slightly reduced in CC57Br/Mv and AKR/J mice. The DNA-binding activities of Ets, AP1 family members, and GME binding proteins were unaffected. HNF3, DNA-binding activity was reduced by 1 h after OAT administration and remained low for 1 mo, as did inhibition of TAT induction in the liver. These results suggested that the inhibitory effect of OAT on the glucocorticoid induction of TAT is mediated by reduced HNF3, DNA-binding activity. 2001 Wiley-Liss, Inc. [source]


    Cytohormonal and morphological alterations in cervicovaginal smears of postmenopausal women on hormone replacement therapy

    DIAGNOSTIC CYTOPATHOLOGY, Issue 10 2006
    Sanjay Gupta M.D.
    Abstract The objective of the study was to study the cytohormonal and morphological alterations in cervicovaginal smears associated with the use of hormone replacement therapy (HRT) and to assess the utility of vaginal cytology in determining the response to HRT. Ninety postmenopausal women (30 on estrogen,progesterone combination (HRT) for 1 to 24 mo (user 1), 30 on estrogen therapy (ERT) for 1 to 44 mo (user 2), and 30 not on any hormones (nonusers)) were included in the cross-sectional study. Their lateral vaginal wall smears and cervical smears were examined for hormonal and morphological assessments, respectively. The smear pattern showed predominance of parabasal cells in 46.6% of nonusers, while none of the users had >70% parabasal cells. A high percentage (>70%) of intermediate cells was found in 46.6% of users and only in 16.6% of nonusers. A high maturation value (MV) was found in more than 75% of users but in only 16.6% of nonusers. The women with high MV (>50) were significantly less symptomatic than did nonusers. Atrophic changes were present in cervical smears of 14/20 (46.6%) nonusers when compared with 1/60 (1.66%) users. Atypical squamous cells of undetermined significance (ASC-US) were diagnosed in seven users and three nonusers. It persisted on follow-up in four users and one nonuser. Histology revealed one mild dysplasia among users. Lactobacilli were more frequently observed in users. The cytohormonal pattern on vaginal smears correlates well with the response to hormonal therapy and clinical symptoms. Awareness of the morphological alterations associated with the use of replacement hormones would enable the cytologists to reduce the false-positive diagnoses while evaluating postmenopausal smears. Diagn. Cytopathol. 2006;34:676,681. 2006 Wiley-Liss, Inc. [source]


    Evidence of Robust Coupling of Atrioventricular Mechanical Function of the Right Side of the Heart: Insights from M-Mode Analysis of Annular Motion

    ECHOCARDIOGRAPHY, Issue 6 2008
    Raveen Bazaz M.D.
    Background: Extensive data exist regarding annular descent and ventricular function. We have already demonstrated significant differences in amplitude and timing of events between maximal mitral (MAPSE) and tricuspid (TAPSE) annular plane systolic excursion as well as described quantitative temporal differences in annular ascent (AA) between the right and left sides of the heart. However, whether any relationship exists between annular ascent and descent components remains uninvestigated. Methods: Left ventricular ejection fraction (LVEF), right ventricular fractional area change (RVFAC), MAPSE, TAPSE, MV, and TV AA as well as pulsed tissue Doppler of the lateral MV and TV annuli were recorded from 53 patients. Results: In this population (age 55 17 years) mean LVEF was 55 19%, mean RVFAC was 47 20%, mean MAPSE was 2.11 0.72 cm, mean TAPSE was 1.48 0.44 cm, mean MV AA was 0.52 0.17 cm, TV AA was 0.96 0.47, MV A-wave 0.10 0.04 cm/s, and TV A-wave was 0.13 0.05 cm/s. A more robust correlation was seen between TV AA and RVFAC than between MV AA and LVEF and also between TV AA and pulsed TDI TV A-wave velocity than between MV AA and pulsed TDI MV A-wave. Conclusion: Our data reveal that mechanical systolic functions of the atria and the ventricles are more closely coupled on the right than on the left side of the heart. Whether this is a result of anatomic linking or chamber geometry will require further study. [source]


    Assessment of the Tilting Properties of the Human Mitral Valve during Three Main Phases of the Heart Cycle: An Echocardiographic Study

    ECHOCARDIOGRAPHY, Issue 4 2006
    Daniel Vanhercke B.N., N.F.E.S.C., R.D.C.S.
    Rationale and Objectives: In experimental models of the left heart, the mitral valve (MV) is commonly implanted perpendicular to a central axis of the apex/MV. To adapt this to a more correct anatomical model, as well as for further studies of the left ventricle, we created a database of implantation angles of the MV and annulus during three main phases of the heart cycle, based on standard cardiac ultrasound measurements. Materials and Methods: Twenty-eight patients were studied with the standard cardiac ultrasound equipment. From the apical echo window, an anteroposterior (AP) plane and a perpendicular commisure-commisure (CC) plane were generated during three critical moments in the heart cycle: systole (S); diastole early filling (E); and diastole late filling (A). In both planes, the angles between the annular plane and each mitral leaflet, as well as the angle between a theoretical longitudinal axis through the apex and center of the MV orifice and the mitral annulus plane, were measured with a custom-made application of Matlab R14. Results: We observed an inclination of the angle mitral annulus/central left ventricle axis, with its lowest point in the direction of the aortic valve (AP plane) of 85 7 in systole (S), 88 8 in early diastole (E), and 88 7 in late diastole (A). In the CC plane, we observed an almost horizontal implantation of 91 5 in systole (S), 91 8 in early diastole (E), and 91 7 in late diastole (A). [source]


    The Double Jeopardy of Blunt Chest Trauma: A Case Report and Review

    ECHOCARDIOGRAPHY, Issue 3 2006
    Subha L. Varahan M.D.
    Cardiac injury, specifically valvular rupture, must be considered after blunt chest trauma even in previously healthy patients. Isolated mitral regurgitation (MR) and tricuspid regurgitation (TR) due to blunt chest trauma are rare phenomena. More unique is simultaneous complete papillary muscle rupture of the mitral valve (MV) and tricuspid valve (TV) with only four patients being previously reported in the literature. This case describes a patient with complete transection of the posteromedial papillary muscle of the MV with severe MR and a concomitant flail TV with severe TR following a motor vehicular accident. The importance of transthoracic and transesophageal echocardiography in the early evaluation of patients following blunt chest trauma is also highlighted by this case. [source]


    3 ISCHEMIC MITRAL VALVE REPAIR: THE IMPACT OF THE MECHANISM OF MITRAL REGURGITATION ON LATE POSTOPERATIVE RESULTS

    ECHOCARDIOGRAPHY, Issue 1 2004
    E. Ereminien
    Aim: The aim of our study was to establish the anatomical-functional mechanisms of ischemic mitral regurgitation (MR) and to analyse its impact on late results after mitral valve (MV) reconstructive surgery. Methods: The study included 53 patients with ischemic MR, who underwent CABG and MV repair. MV surgery consisted of subvalvular apparatus repair and/or annuloplasty. 2D Doppler investigations performed pre-, 10,14 days, and 12 months after surgery included evaluation of MV and left ventricular (LV) geometry and function. Results: Analysis of the mechanisms of ischemic MR permitted dividing patients into two groups: group 1,29 patients with inferobasal scar and posterior papillary muscle (PM) displacement, including 22 patients with PM infarction and 7 patients without it, and group 2,24 patients with isolated mitral annulus (MA) dilation. In the case of PM infarction two different mechanisms of MR were stated: (a) P3 restriction and A3 prolapse due to chordal tethering, (b) A3 P3 (commissural) prolapse due to chordal papillary elongation. Preoperatively LV geometry and function were better preserved in group 1 and late MV repair results were better versus (vs.) group 2: LV end-systolic diameter index decreased from 22.9 3.1 mm/m2 to 20.9 3.6 mm/m2 at 1 year, p < 0.05, LV ejection fraction increased from 34.9 8.4 to 41.8 8.1%, respectively, p < 0.05. No significant changes in LV geometry and function were noted in group 2. Conclusions: The underlying mechanism of ischemic MR has an impact on MV repair results. In patients with MR due to posterobasal infarction MV repair resulted in more favorable postoperative effect-marked improvement in LV geometry and function late after surgery versus MR due to isolated MA dilation. [source]


    Laboratory diagnosis of variant Creutzfeldt,Jakob disease

    HISTOPATHOLOGY, Issue 1 2000
    J W Ironside
    The neuropathological and biochemical features of 33 cases of variant Creutzfeldt,Jakob disease (vCJD) diagnosed up to the end of 1998 are analysed in relation to the 646 cases of suspected CJD referred to the CJD Surveillance Unit laboratory from 1990 to 1998. Morphological studies of the central nervous system, lymphoid tissues and other organs were accompanied by immunocytochemistry; Western blot analysis of PrPRES was performed on frozen brain tissue. The findings were analysed in relation to clinical and genetic data. The pathology of vCJD showed morphological and immunocytochemical characteristics distinct from other cases of CJD. PrP accumulation was widespread in lymphoid tissues in vCJD, but was not identified in other non-neural tissues. PrPRES accumulation in vCJD brain tissue showed a uniform glycotype pattern distinct from sporadic CJD. All analysed cases of vCJD were methionine homozygotes at codon 129 of the PrP gene. No evidence currently exists to suggest that cases of CJD diagnosed in individuals who are MV or VV at codon 129 of the PrP gene represent ,human bovine spongiform encaphalopathy (BSE)'. Continued surveillance is required to further investigate this possibility, with the need to investigate autopsy tissues from suspected cases by histological and biochemical techniques. [source]


    Prospective study of body mass index, height, physical activity and incidence of bladder cancer in US men and women

    INTERNATIONAL JOURNAL OF CANCER, Issue 1 2007
    Crystal N. Holick
    Abstract We evaluated prospectively the association between body mass index (BMI), height, recreational physical activity and the risk of bladder cancer among US adults. Data were used from 2 ongoing cohorts, the Health Professionals Follow-up Study and the Nurses' Health Study, with 3,542,012 years of follow-up and 866 incident bladder cancer cases (men = 507; women = 359) for the anthropometric analysis and 1,890,476 years of follow-up and 706 incident bladder cancer cases (men = 502; women = 204) for the physical activity analysis. Cox proportional hazard models were used to estimate incidence rate ratios (RR) and 95% confidence intervals (CI) between BMI, height, physical activity and bladder cancer risk adjusting for age, pack-years of cigarette smoking and current smoking. Estimates from each cohort were pooled using a random-effects model. We observed no association between baseline BMI and bladder cancer risk, even when we compared a BMI of ,30 kg/m2 to a BMI of 18,22.9 kg/m2 [pooled multivariate (MV) RR, 1.16; 95% CI: 0.89,1.52]. A weak, but statistically significant, association was observed for the same comparison after excluding bladder cancer cases diagnosed within the first 4 years of follow-up (pooled MV RR, 1.33; 95% CI: 1.01,1.76). Height was not related to bladder cancer risk (pooled MV RR, 0.82; 95% CI: 0.65,1.03, top vs. bottom quintile). Total recreational physical activity also was not associated with the risk of bladder cancer (pooled MV RR, 0.97; 95% CI: 0.77,1.24, top vs. bottom quintile). Our findings do not support a role for BMI, height or physical activity in bladder carcinogenesis. 2006 Wiley-Liss, Inc. [source]


    Interleukin-10 expression significantly correlates with minor CD8+ T-cell infiltration and high microvessel density in patients with gastric cancer

    INTERNATIONAL JOURNAL OF CANCER, Issue 8 2006
    Teruhisa Sakamoto
    Abstract We aimed to investigate the relationships between interleukin-10 (IL-10) expression and both the clinicopathological findings and prognoses in patients with gastric cancer and to compare IL-10 expression with microvessel (MV) density and CD8+ T lymphocyte infiltration to evaluate its effects on angiogenesis and immune responses in gastric cancer. IL-10 expression was determined in gastric cancer patients by reverse transcription-polymerase chain reaction (RT-PCR) or immunohistochemical procedures. Two of 7 normal gastric tissues showed IL-10 mRNA expression, while its expressions were confirmed in all advanced gastric carcinoma tissues examined (n = 11) by RT-PCR. Immunohistochemical staining demonstrated that IL-10 expression was detected in 52 (47.7%) of 109 cases. There was a close correlation between IL-10 expression and MV density. IL-10 expression inversely correlated with CD8+ T-lymphocyte infiltration. The prognoses of patients whose tumors expressed IL-10 were significantly worse than those of patients whose tumors did not express IL-10. Multivariate analysis indicated IL-10 expression was an independent prognostic factor. IL-10 might be associated with tumor progression by stimulating angiogenesis and suppressing immune responses in gastric cancer. 2005 Wiley-Liss, Inc. [source]


    Multipole moments and polarizability of molecular systems with D3h symmetry in orbitally degenerate states

    INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 6 2006
    I. Ya.
    Abstract It was proved, by ab initio studies, that the electronic ground states of the molecules MF3 (MV, Cr, Mn), M3 (MLi, Na, K), and C3H3, with D3h symmetry, have orbital degeneracy. It was shown that in the base functions of these degenerate states, the reduced matrix elements of the in-plane E,-type components of the dipole moment, of the quadrupole moments and of the nontotal symmetric components of the (hyper)polarizability are nonzero. The computed values of the dipole and quadrupole moments of the polarizability and hyperpolarizabilities are comparable to those of the molecular systems of the lower than D3h symmetry. 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006 [source]


    Multicenter Blinded Analysis of RT-PCR Detection Methods for Paramyxoviruses in Relation to Paget's Disease of Bone,

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 4 2007
    Stuart H Ralston MD
    Abstract Conflicting results have been reported on the detection of paramyxovirus transcripts in Paget's disease, and a possible explanation is differences in the sensitivity of RT-PCR methods for detecting virus. In a blinded study, we found no evidence to suggest that laboratories that failed to detect viral transcripts had less sensitive RT-PCR assays, and we did not detect measles or distemper transcripts in Paget's samples using the most sensitive assays evaluated. Introduction: There is conflicting evidence on the possible role of persistent paramyxovirus infection in Paget's disease of bone (PDB). Some workers have detected measles virus (MV) or canine distemper virus (CDV) transcripts in cells and tissues from patients with PDB, but others have failed to confirm this finding. A possible explanation might be differences in the sensitivity of RT-PCR methods for detecting virus. Here we performed a blinded comparison of the sensitivity of different RT-PCR,based techniques for MV and CDV detection in different laboratories and used the most sensitive assays to screen for evidence of viral transcripts in bone and blood samples derived from patients with PDB. Materials and Methods: Participating laboratories analyzed samples spiked with known amounts of MV and CDV transcripts and control samples that did not contain viral nucleic acids. All analyses were performed on a blinded basis. Results: The limit of detection for CDV was 1000 viral transcripts in three laboratories (Aberdeen, Belfast, and Liverpool) and 10,000 transcripts in another laboratory (Manchester). The limit of detection for MV was 16 transcripts in one laboratory (NIBSC), 1000 transcripts in two laboratories (Aberdeen and Belfast), and 10,000 transcripts in two laboratories (Liverpool and Manchester). An assay previously used by a U.S.-based group to detect MV transcripts in PDB had a sensitivity of 1000 transcripts. One laboratory (Manchester) detected CDV transcripts in a negative control and in two samples that had been spiked with MV. None of the other laboratories had false-positive results for MV or CDV, and no evidence of viral transcripts was found on analysis of 12 PDB samples using the most sensitive RT-PCR assays for MV and CDV. Conclusions: We found that RT-PCR assays used by different laboratories differed in their sensitivity to detect CDV and MV transcripts but found no evidence to suggest that laboratories that previously failed to detect viral transcripts had less sensitive RT-PCR assays than those that detected viral transcripts. False-positive results were observed with one laboratory, and we failed to detect paramyxovirus transcripts in PDB samples using the most sensitive assays evaluated. Our results show that failure of some laboratories to detect viral transcripts is unlikely to be caused by problems with assay sensitivity and highlight the fact that contamination can be an issue when searching for pathogens by sensitive RT-PCR,based techniques. [source]


    Mini-Maze Suffices as Adjunct to Mitral Valve Surgery in Patients with Preoperative Atrial Fibrillation

    JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2000
    ANTON E. TUINENBURG M.D.
    Mini-Maze and Mitral Valve Surgery. Introduction: After mitral valve (MV) surgery, preoperative atrial fibrillation (AF) often recurs while cardioversion therapy generally fails. Additional Cox maze surgery improves postoperative arrhythmia outcome, but the extensive nature of such an approach limits general appliance. We investigated the clinical outcome of a simplified, less extensive Cox maze procedure ("mini-maze") as adjunct to MV surgery. Methods and Results: Thirteen patients with MV disease and preoperative AF were treated with combined surgery (group 1). Nine control patients without previous AF underwent isolated MV surgery (group 2). We retrospectively compared the results to findings in 23 patients with preoperative AF who had undergone isolated MV surgery (group 3). In group 1, mini-maze took an additional 46 minutes of perfusion time. One 75-year-old patient died of postoperative multiple organ failure. Seven patients showed spontaneously converting (within 2 months) postoperative AF. After 1 year, 82% were in sinus rhythm (SR). No sinus node dysfunction was observed. In group 2, all patients were in SR after 1 year. In group 3, only 53% were in SR after 1 year, despite serial cardioversion and antiarrhythmic drug therapy. Exercise tolerance and heart rate were comparable for groups 1 and 2. Left atrial function was present in all but one patient in group 1 and in all patients in group 2 (after MV reconstruction). Conclusion: Adding a relatively simple mini-maze to MV surgery improves arrhythmia outcome in patients with preoperative AF without introducing sinus node dysfunction or persistent absence of left atrial function. The results of this type of combined surgery are encouraging and deserve further attention. [source]


    Human liver stem cell-derived microvesicles accelerate hepatic regeneration in hepatectomized rats

    JOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 6b 2010
    M. B. Herrera
    Abstract Several studies indicate that adult stem cells may improve the recovery from acute tissue injury. It has been suggested that they may contribute to tissue regeneration by the release of paracrine factors promoting proliferation of tissue resident cells. However, the factors involved remain unknown. In the present study we found that microvesicles (MVs) derived from human liver stem cells (HLSC) induced in vitro proliferation and apoptosis resistance of human and rat hepatocytes. These effects required internalization of MVs in the hepatocytes by an ,4 -integrin-dependent mechanism. However, MVs pre-treated with RNase, even if internalized, were unable to induce hepatocyte proliferation and apoptosis resistance, suggesting an RNA-dependent effect. Microarray analysis and quantitative RT-PCR demonstrated that MVs were shuttling a specific subset of cellular mRNA, such as mRNA associated in the control of transcription, translation, proliferation and apoptosis. When administered in vivo, MVs accelerated the morphological and functional recovery of liver in a model of 70% hepatectomy in rats. This effect was associated with increase in hepatocyte proliferation and was abolished by RNase pre-treatment of MVs. Using human AGO2, as a reporter gene present in MVs, we found the expression of human AGO2 mRNA and protein in the liver of hepatectomized rats treated with MVs. These data suggested a translation of the MV shuttled mRNA into hepatocytes of treated rats. In conclusion, these results suggest that MVs derived from HLSC may activate a proliferative program in remnant hepatocytes after hepatectomy by a horizontal transfer of specific mRNA subsets. [source]


    Prethymectomy plasmapheresis in myasthenia gravis

    JOURNAL OF CLINICAL APHERESIS, Issue 4 2005
    Jiann-Horng Yeh
    Abstract Plasma exchange before thymectomy may decrease the time on mechanical ventilation (MV) and shorten the stay in the intensive care unit (ICU) for patients with myasthenia gravis (MG). This study evaluated the effects of prethymectomy plasmapheresis. A total of 29 myasthenic patients, 18 women and 11 men aged 20,73 years, were treated with double filtration plasmapheresis (DFP) for two to five consecutive sessions over a period between 2 and 21 days (mean 8.1 days) before transsternal thymectomy. Acetylcholine receptor antibody (AchRAb) titers, vital capacity (VC), maximal inspiratory pressure (Pimax), and MG score were measured before and after the course of DFP. Three outcome measures including duration of postoperative hospital stay, duration of ICU stay, and duration of MV were analyzed for correlation with clinical variables. The duration of MV ranged from 6 to 93 h, with a median of 21 h. The median ICU stay was one day and the median postoperative hospital stay was 10 days. A higher removal rate of AchRAb was associated with a shorter duration of ICU and postoperative hospital stay (P = 0.001 and 0.019, respectively). Postoperative hospital stay was strongly correlated with post-DFP Pimax (P = 0.010), and marginally correlated with pre-DFP VC (P = 0.047) and to a lesser extent with pre-DFP Pimax (P = 0.063). Univariate analysis using the log rank test revealed that removal rate of AchRAb <30% (P = 0.043) and pre-DFP Pimax <,60 cmH2O (P = 0.024) were significantly associated with prolonged ICU stay. Risk factors for prolonged postoperative stay included post-DFP Pimax <,60 cmH2O (P = 0.017), pre-DFP Pimax <,60 cmH2O (P = 0.031), and post-DFP VC < 1.0 L (P = 0.046). Our results confirmed the efficacy and safety of DFP in prethymectomy preparation for myasthenic patients. J. Clin. Apheresis, 2005 2005 Wiley-Liss, Inc. [source]


    Prediction of octanol,water partition coefficients of organic compounds by multiple linear regression, partial least squares, and artificial neural network

    JOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 15 2009
    Hassan Golmohammadi
    Abstract A quantitative structure,property relationship (QSPR) study was performed to develop models those relate the structure of 141 organic compounds to their octanol,water partition coefficients (log Po/w). A genetic algorithm was applied as a variable selection tool. Modeling of log Po/w of these compounds as a function of theoretically derived descriptors was established by multiple linear regression (MLR), partial least squares (PLS), and artificial neural network (ANN). The best selected descriptors that appear in the models are: atomic charge weighted partial positively charged surface area (PPSA-3), fractional atomic charge weighted partial positive surface area (FPSA-3), minimum atomic partial charge (Qmin), molecular volume (MV), total dipole moment of molecule (,), maximum antibonding contribution of a molecule orbital in the molecule (MAC), and maximum free valency of a C atom in the molecule (MFV). The result obtained showed the ability of developed artificial neural network to prediction of partition coefficients of organic compounds. Also, the results revealed the superiority of ANN over the MLR and PLS models. 2009 Wiley Periodicals, Inc. J Comput Chem, 2009 [source]


    Isoflurane attenuates pulmonary interleukin-1, and systemic tumor necrosis factor-, following mechanical ventilation in healthy mice

    ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 6 2009
    M. VANEKER
    Background: Mechanical ventilation (MV) induces an inflammatory response in healthy lungs. The resulting pro-inflammatory state is a risk factor for ventilator-induced lung injury and peripheral organ dysfunction. Isoflurane is known to have protective immunological effects on different organ systems. We tested the hypothesis that the MV-induced inflammatory response in healthy lungs is reduced by isoflurane. Methods: Healthy C57BL6 mice (n=34) were mechanically ventilated (tidal volume, 8 ml/kg; positive end-expiratory pressure, 4 cmH2O; and fraction of inspired oxygen, 0.4) for 4 h under general anesthesia using a mix of ketamine, medetomidine and atropine (KMA). Animals were divided into four groups: (1) Unventilated control group; (2) MV group using KMA anesthesia; (3) MV group using KMA with 0.25 MAC isoflurane; (4) MV group using KMA with 0.75 MAC isoflurane. Cytokine levels were measured in lung homogenate and plasma. Leukocytes were counted in lung tissue. Results: Lung homogenates: MV increased pro-inflammatory cytokines. In mice receiving KMA+ isoflurane 0.75 MAC, no significant increase in interleukin (IL)-1, was found compared with non-ventilated control mice. Plasma: MV induced a systemic pro-inflammatory response. In mice anesthetized with KMA+ isoflurane (both 0.25 and 0.75 MAC), no significant increase in tumor necrosis factor (TNF)-, was found compared with non-ventilated control mice. Conclusions: The present study is the first to show that isoflurane attenuates the pulmonary IL-1, and systemic TNF-, response following MV in healthy mice. [source]


    Percutaneous Mitral Valve Repair for Mitral Regurgitation

    JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 1 2003
    PETER C. BLOCK M.D.
    Mitral regurgitation (MR) associated with, ischemic, and degenerative (prolapse) disease, contributes to left ventricular (LV) dysfunction due to remodeling, and LV dilation, resulting in worsening of MR. Mitral valve (MV) surgical repair has provided improvement in survival, LV function and symptoms, especially when performed early. Surgical repair is complex, due to diverse etiologies and has significant complications. The Society for Thoracic Surgery database shows that operative mortality for a 1st repair is 2% and for re-do repair is 4 times that. Cardiopulmonary bypass and cardiac arrest are required. The attendant morbidity prolongs hospitalization and recovery. Alfieri simplified mitral repair using an edge-to-edge technique which subsequently has been shown to be effective for multiple etiologies of MR. The MV leaflers are typically brought together by a central suture producing a double orifice MV without stenosis. Umana reported that MR decreased from grade 3.6 +/,0.5 to0.8 +/,0.4 (P < 0.0001)and LV ejection fraction increased from 33 +/,13% to 45 +/,11%(P = 0.0156). In 121 patients, Maisano reported freedom from re-operation of 95 +/,4.8% with up to 6 year follow-up. Oz developed a MV "grasper" that is directly placed via a left ventriculotomy and coapts both leaflets which are then fastened by a graduated spiral screw. An in-vitro model using explanted human valves showed significant reduction in MR and in canine studies, animals followed by serial echo had persistent MV coaptation. At 12 weeks the device was endothelialized. These promising results have paved the way for a percutaneous or minimally invasive off pump mitral repair. Evalve has developed catheter-based technology, which, by apposing the edges of a regurgitant MV, results in edge-to-edge repair. Release of the device is done after echo and fluoroscopic evaluation under normal loading conditions. If the desired effect is not produced the device can be repositioned or retrieved. Animal studies show excellent healing, with incorporation of the device into the leaflets at 6,10 weeks with persistent coaptation. Another percutaneous approach has been to utilize the proximity of the coronary sinus (CS) to the mitral annulus (MA). Placement of a self-compressing device in the CS along the region of the posterior MA has, in canine models, reduced MR and addresses the issues of MA dilation and its contribution to MR. Ongoing studies are underway for both techniques. (J Interven Cardiol 2003;16:93,96) [source]


    Co-circulation of two genotypes of measles virus and mutual change of the prevailing genotypes every few years in Osaka, Japan

    JOURNAL OF MEDICAL VIROLOGY, Issue 2 2003
    Hideyuki Kubo
    Abstract Genotypes of 44 wild-type measles virus (MV) strains isolated in Osaka, Japan, during 1997,2001, were determined based on phylogenetic analyses of a 456-nt 3, terminal nucleoprotein gene sequence with the reference MV strains designated by the World Health Organization. The wild-type MV strains were classified into two genotypes, D3 and D5, recognized as indigenous in Japan. Six of 12 strains isolated in 1997 were classified into genotype D3 and the other 6 into D5. Eleven of 13 strains were D3, and 2 were D5 in 1998. There were no measles epidemics, and no strains were isolated in 1999. Nine of 10 strains were genotype D5, and only one was D3 in 2000, and 9 of 9 were D5 in 2001. These results indicate that the wild-type MV strains classified into genotypes D3 and D5 co-circulated without the complete change of the MV genotype in Osaka, except in 2001. Furthermore, the prevailing genotype was different between 1998 and 2000,2001. Together with a previous report about MV genotype in this area during 1993,1995, these results suggest that the mutual change of the prevailing wild-type MV genotypes between D3 and D5 occurs every few years in Osaka, Japan. J. Med. Virol. 69:273,278, 2003. 2003 Wiley-Liss, Inc. [source]


    The relaxations of temporal bond polarizabilities of methylviologen adsorbed on the Ag electrode by 514.5 nm excitation: a Raman intensity study

    JOURNAL OF RAMAN SPECTROSCOPY, Issue 3 2009
    Chao Fang
    Abstract An algorithm to elucidate the temporal bond polarizabilities from the surface enhanced Raman (SERS) intensities was employed to the case of methylviologen (MV) adsorbed on the Ag electrode. This enables us to obtain the properties of its SERS mechanisms and the effect of its adsorption. The analysis shows that the charge transfer and electromagnetic mechanisms involving in this MV SERS system possess different relaxation times for its various temporal bond polarizabilities. The physics is that the process involved in the charge transfer mechanism will take longer time than that involved in the electromagnetic mechanism since it needs more time to redistribute the charges during relaxation. The time division between these two mechanisms is figured out to be around 3 ps for this system. Adsorption also enhances the relaxation of the temporal bond polarizabilities, in general. The adsorption effect is indicated by the temporal bond polarizabilities close to the final stage of relaxation. They are, in fact, the quantities parallel to the bond electronic densities in the molecular orbital (MO) concept. For comparison, the case of MV solid was also analyzed. Copyright 2008 John Wiley & Sons, Ltd. [source]


    Independent Effects of Nitrogen Substitution for Oxygen and Yttrium Substitution for Magnesium on the Properties of Mg-Y-Si-Al-O-N Glasses

    JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 3 2003
    Michael J. Pomeroy
    Glasses of composition (in equivalent percent) (28 ,x)Mg:xY:56Si:16Al:(100 ,y)O:yN, with x= 0, 14, or 28 for y= 0 and 15 and with x= 0, 7, 14, 21, or 28 for y= 10, were prepared by melting and casting. For glasses where the nitrogen content was varied for a constant cationic ratio, the glass molar volume (MV), compactness (C), Young's modulus (E), glass-transition temperature (Tg), and dilatometric-softening temperature (Tds) varied linearly as the nitrogen content increased, with MV decreasing and the other properties increasing. From the incremental changes in these properties with nitrogen content, for glasses with x= 0, 14, and 28, good linear fits (R2 > 0.99) were obtained, and best-fit slopes are reported here. The property changes and their linearity were consistent with the increased cross-linking of the glass network by tricoordinated nitrogen. The replacement of magnesium by yttrium led to a nonlinear decrease in glass compactness and to nonlinear increases in MV, Tg, and Tds. However, linear correlations were found for MV and ionic volume and for Tg, Tds, and the coordination of (Si,Al)(O,N) tetrahedra of the glass structural units to the modifier cations not involved in charge compensating aluminum ions in fourfold coordination. The replacement of magnesium by yttrium had little effect on Young's modulus, and this result was related to similar changes in the compactness, C. The present results showed that the effects of substituting nitrogen for oxygen and yttrium for magnesium are independent and additive; thus, no synergistic effects of anion and cation substitutions were observed. [source]


    Quantitative Electromyographic Examination in Myogenic Disorders of 6 Horses

    JOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 2 2003
    I.D. Wijnberg
    Electromyographic needle examination (EMG), including the semiautomatic quantitative analysis of motor unit action potential (MUAP), is an important diagnostic tool for myopathy in humans. The diagnostic possibilities of this technique have not been fully explored in horses; however, recent studies have shown that MUAP analysis can be performed in conscious horses. To determine the diagnostic possibilities of EMG in horses, we compared the EMG results of the subclavian muscle, the triceps, and the lateral vastus muscle in 6 equine patients thought to have myogenic disorders with those in 7 normal control horses. The EMG results were compared with the results of the histopathologic examination of the lateral vastus muscle in patients and controls. Histopathologic examination showed muscle disease in 3 patients. In the patient group, several types of abnormal spontaneous activities were observed (mainly fibrillation potentials and positive sharp waves), and the MUAPs of the patient group had a markedly shorter duration and lower amplitude than those of the control group. In the subclavian muscle, triceps, and lateral vastus muscle of affected horses, the MUAP duration was 5.0 0.4 (mean SD), 3.9 0.3, and 4.7 1.1 milliseconds, respectively. The MUAP amplitude was 217 55, 150 74, and 180 54 MV; the number of phases was 2.4 0.2, 2.5 0.3, and 2.3 0.1; and the number of turns was 2.6 0.2, 2.4 0.2, and 2.8 0.5, respectively. In conclusion, it appears that the EMG may be a more sensitive method than other techniques for examining muscle biopsies for diagnosis of early-stage myopathy in horses. [source]


    Progressive Renal Vascular Proliferation and Injury in Obese Zucker Rats

    MICROCIRCULATION, Issue 4 2010
    RADU ILIESCU
    Microcirculation (2010) 17, 250,258. doi: 10.1111/j.1549-8719.2010.00020.x Abstract Objective:, Obesity, an independent risk factor for chronic kidney disease, may induce renal injury by promoting inflammation. Inflammatory cytokines can induce neovascularization in different organs, including the kidneys. However, whether obesity triggers renal neovascularization and, if so, its effect on renal function has never been investigated. Methods:, Blood pressure, proteinuria, and glomerular filtration rate (GFR) were measured in vivo. Renal microvascular (MV) architecture was studied by 3D micro-CT in lean and obese Zucker rats (LZR and OZR, n = 7/group) at 12, 22, and 32 weeks of age. Renal inflammation was assessed by quantifying interleukin (IL)-6, tumor necrosis factor (TNF)-alpha, and ED-1 expression, as renal fibrosis in trichrome-stained cross-sections. Results:, Mild inflammation and lower GFR was only observed in younger OZR, without renal fibrosis or changes in MV density. Interestingly, renal MV density increased in OZR at 32 weeks of age, accompanied by pronounced increase in renal IL-6 and TNF-alpha, ED-1+ cells, proteinuria, decreased GFR, and fibrosis. Conclusions:, This study shows increased renal cortical vascularization in experimental obesity, suggesting neovascularization as an evolving process as obesity progresses. Increased renal vascularization, possibly triggered by inflammation, may reflect an initially compensatory mechanism in obesity. However, increased inflammation and inflammatory-induced neovascularization may further promote renal injury as obesity advances. [source]


    Cosmic flows on 100 h,1 Mpc scales: standardized minimum variance bulk flow, shear and octupole moments

    MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2010
    Hume A. Feldman
    ABSTRACT The low-order moments, such as the bulk flow and shear, of the large-scale peculiar velocity field are sensitive probes of the matter density fluctuations on very large scales. In practice, however, peculiar velocity surveys are usually sparse and noisy, which can lead to the aliasing of small-scale power into what is meant to be a probe of the largest scales. Previously, we developed an optimal ,minimum variance' (MV) weighting scheme, designed to overcome this problem by minimizing the difference between the measured bulk flow (BF) and that which would be measured by an ideal survey. Here we extend this MV analysis to include the shear and octupole moments, which are designed to have almost no correlations between them so that they are virtually orthogonal. We apply this MV analysis to a compilation of all major peculiar velocity surveys, consisting of 4536 measurements. Our estimate of the BF on scales of ,100 h,1 Mpc has a magnitude of |v| = 416 78 km s ,1 towards Galactic l= 282 11 and b= 6 6. This result is in disagreement with , cold dark matter with Wilkinson Microwave Anisotropy Probe 5 (WMAP5) cosmological parameters at a high confidence level, but is in good agreement with our previous MV result without an orthogonality constraint, showing that the shear and octupole moments did not contaminate the previous BF measurement. The shear and octupole moments are consistent with WMAP5 power spectrum, although the measurement noise is larger for these moments than for the BF. The relatively low shear moments suggest that the sources responsible for the BF are at large distances. [source]


    Where are the cosmic metals at z, 3?

    MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 1 2008
    Jesper Sommer-Larsen
    ABSTRACT The global temperature distribution of the cosmic gas-phase oxygen at z, 3 is determined by combining high-resolution cosmological simulations of individual protogalactic as well as larger regions with the observed, extinction-corrected, rest-frame V -band galaxy luminosity function. The simulations have been performed with three different stellar initial mass functions (IMFs), a Kroupa (K98), a Salpeter (S) and an Arimoto,Yoshii (AY), spanning a range of a factor of 5 in chemical yield and specific supernova type II energy feedback. Gas-phase oxygen is binned according to T as log(T) , 4.0 (,cold'), log(T) , 4.5 (,warm') and log(T) , 5.0, 5.5, 6.0, 6.5, 7.0 (,hot' phases). Oxygen is found to be distributed over all T phases, in particular for the top-heavy AY IMF. But, at variance with previous works, it is found that for the K98 and S IMFs the cold phase is the most important. For these IMFs it contains 47 and 37 per cent, respectively, of all gas-phase oxygen, mainly at fairly high density, nH, 0.1 cm,3. The implications of this in relation to observational damped Ly, absorber studies are discussed. In relation to ,missing metals' it is found that a significant fraction of the oxygen is located in a warm/hot phase that may be very difficult to detect. Moreover, it is found that less than about 20,25 per cent of the cosmic oxygen is associated with galaxies brighter than MV,,22, i.e. the faintest galaxy luminosities probed by current metallicity determinations for Lyman-break galaxies (LBGs). Hence, 75,80 per cent of the oxygen is also in this sense ,missing'. From the LBG-based, ,, 1500 ultraviolet luminosity density history at z, 3, we obtain an essentially IMF-independent constraint on the mean oxygen density at z= 3. We compare this to what is obtained from our models, for the three different IMFs. We find that the K98 IMF is strongly excluded, as the chemical yield is simply too small, the Salpeter is marginally excluded, and the AY matches the constraint well. The K98 IMF can only match the data if the ,, 1500 extinction corrections have been overestimated by factor of ,4, which seems highly unlikely. The yields for K98 are also far too small to match the observational data for C iv. The optimal IMF should have a yield intermediate between the S and AY. [source]


    Structural parameters of Mayall II = G1 in M31

    MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2007
    J. Ma
    ABSTRACT Mayall II = G1 is one of the most luminous globular clusters (GCs) known in M31. New deep, high-resolution observations with the Advanced Camera for Surveys on the Hubble Space Telescope are used to provide accurate photometric data to the smallest radii yet. In particular, we present the precise variation of ellipticity and position angle, and of surface brightness for the core of the object. Based on these accurate photometric data, we redetermine the structural parameters of G1 by fitting a single-mass isotropic King model. We derive a core radius, rc= 0.21 0.01 arcsec (= 0.78 0.04 pc), a tidal radius, rt= 21.8 1.1 arcsec (= 80.7 3.9 pc), and a concentration index c= log (rt/rc) = 2.01 0.02. The central surface brightness is 13.510 mag arcsec,2. We also calculate the half-light radius, at rh= 1.73 0.07 arcsec (= 6.5 0.3 pc). The results show that, within 10 core radii, a King model fits the surface brightness distribution well. We find that this object falls in the same region of the MV versus log Rh diagram as , Centauri, M54 and NGC 2419 in the Milky Way. All three of these objects have been claimed to be the stripped cores of now defunct dwarf galaxies. We discuss in detail whether GCs, stripped cores of dwarf spheroidals and normal dwarf galaxies form a continuous distribution in the MV versus log Rh plane, or if GCs and dwarf spheroidals constitute distinct classes of objects; we present arguments in favour of this latter view. [source]


    Discovery and analysis of three faint dwarf galaxies and a globular cluster in the outer halo of the Andromeda galaxy,

    MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2006
    N. F. Martin
    ABSTRACT We present the discovery of three faint dwarf galaxies and a globular cluster in the halo of the Andromeda galaxy (M31), found in our MegaCam survey that spans the southern quadrant of M31, from a projected distance of ,50 to ,150 kpc. Though the survey covers 57 deg2, the four satellites lie within 2 of one another. From the tip of the red giant branch (RGB), we estimate that the globular cluster lies at a distance of 631 58 kpc from the Milky Way and along with a ,100 kpc projected distance from M31 we derive a total distance of 175 55 kpc from its host, making it the farthest M31 globular cluster known. It also shows the typical characteristics of a bright globular cluster, with a half-light radius of 2.3 0.2 pc and an absolute magnitude in the V band of MV,0=,8.5 0.3. Isochrone fitting reveals that it is dominated by a very old population with a metallicity of [Fe/H],,1.3. The three dwarf galaxies are revealed as overdensities of stars that are aligned along the RGB tracks in their colour,magnitude diagrams. These satellites are all very faint, with absolute magnitudes in the range ,7.3 ,MV,0,,6.4, and show strikingly similar characteristics with metallicities of [Fe/H],,1.4 and half-light radii of ,120 45 pc, making these dwarf galaxies two to three times smaller than the smallest previously known satellites of M31. Given their faintness, their distance is difficult to constrain, but we estimate them to be between 740 and 955 kpc which places them well within the virial radius of the host galaxy. The panoramic view of the MegaCam survey can provide an unbiased view of the satellite distribution of the Andromeda galaxy and, extrapolating from its coverage of the halo, we estimate that up to 45 20 satellites brighter than MV,,6.5 should be orbiting M31. Hence faint dwarf galaxies cannot alone account for the missing satellites that are predicted by , cold dark matter models, unless they reside in dark matter minihaloes that are more massive than the typical masses of 107 M, currently inferred from their central radial velocity dispersion. [source]


    Stem cells in craniofacial and dental tissue engineering

    ORTHODONTICS & CRANIOFACIAL RESEARCH, Issue 2 2005
    MV Risbud
    Abstract Authors ,, Risbud MV, Shapiro IM Mesenchymal stem cells (MSC) have been identified in a variety of adult tissues as a population of pluripotential self-renewing cells. Based on their adherence and colony forming properties, a small number of MSC can be isolated from most mesenchymal tissues as well as bone marrow. In the presence of one or more growth factors, these cells commit to lineages that lead to the formation of bone, cartilage, muscle, tendon and adipose tissue; recent studies indicate that stem cells for cementum, dentine and the periodontal ligament also exist. All of these cells can be expanded in vitro, and, embedded in a scaffold, inserted into defects to promote healing and tissue replacement. Increased understanding of the molecular mechanism directing lineage specification and morphogenesis is providing a rational approach for the regeneration of craniofacial tissues and oral structures. [source]


    Low donor-to-recipient weight ratio does not negatively impact survival of pediatric heart transplant patients

    PEDIATRIC TRANSPLANTATION, Issue 6 2010
    Liwen Tang
    Tang L, Du W, Delius RE, L'Ecuyer TJ, Zilberman MV. Low donor-to-recipient weight ratio does not negatively impact survival of pediatric heart transplant patients. Pediatr Transplantation 2010: 14:741,745. 2010 John Wiley & Sons A/S. Abstract:, A major limitation to success in pediatric heart transplantation is donor organ shortage. While the use of allografts from donors larger than the recipient is accepted, the use of undersized donor grafts is generally discouraged. Using the UNOS database, we wanted to evaluate whether using smaller donor hearts affects the short- and long-term survival of pediatric heart transplant patients. A retrospective analysis of data entered into the UNOS database from April 1994 to May 2008 was performed. Pediatric heart transplant recipients (ages 0,18 yr) with DRWR <2.0 were identified and divided into two groups: Low-DRWR (<0.8) and Ideal-DRWR (0.8,2.0). Patients' demographics, pretransplant diagnoses, age at transplantation, severity of pretransplant condition, and rate of complications prior to hospital discharge after transplantation were noted. Fisher's exact, chi-square, and Wilcoxon rank sum tests were used to compare patients' baseline characteristics. Kaplan,Meier curves and Cox proportional hazard regression were used to compare patients' survival and to identify independent risk factors for outcomes. There were 3048 patients (204 with Low- and 2844 with Ideal-DRWR). The Low-ratio group patients were older (8.3 vs. 6.9 yr; p = 0.001), there was a slight male predominance in the Low-DRWR group (p = 0.055). The Low-DRWR group had longer transplant wait time than the Ideal-DRWR group (97 vs. 85 days; p = 0.04). The groups did not differ in race, primary diagnoses, severity of pretransplant condition (medical urgency status, need for ventilation, inotropic support, ECMO, nitric oxide, or dialysis, the PVR for those with bi-ventricular anatomy), or post-transplant complications (length of stay, need for inotropic support, dialysis, and rate of infections). The Low-DRWR patients had less episodes of acute rejection during the first-post-transplant month. Infants with DRWR 0.5,0.59 had lower 30-day survival rate (p = 0.045). There was no difference in short- and long-term survival between the patients with DRWR 0.6,0.79 and DRWR 0.8,2.0. Use of smaller allografts (DRWR 0.6,0.8) has no negative impact on the short- and long-term survival of pediatric heart transplant patients. [source]


    Polarization effects and phase equilibria in high-energy-density polyvinylidene-fluoride-based polymers

    ACTA CRYSTALLOGRAPHICA SECTION A, Issue 5 2010
    V. Ranjan
    Using first-principles calculations, the phase diagrams of polyvinylidene fluoride (PVDF) and its copolymers under an applied electric field are studied and phase transitions between their nonpolar , and polar , phases are discussed. The results show that the degree of copolymerization is a crucial parameter controlling the structural phase transition. In particular, for tetrafluoroethylene (TeFE) concentration above 12%, PVDF,TeFE is stabilized in the , phase, whereas the , phase is stable for lower concentrations. As larger electric fields are applied, domains with smaller concentrations ( 12%) undergo a transition from the , to the , phase until a breakdown field of ~600,MV,m,1 is reached. These structural phase transitions can be exploited for efficient storage of electrical energy. [source]