990 resultados para temporal-pulse phase
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OBJECTIVES: To determine the pharmacodynamic (PD) profile of serum total testosterone levels (TT) and luteinizing hormone (LH) in men with secondary hypogonadism following initial and chronic daily oral doses of enclomiphene citrate in comparison to transdermal testosterone. To determine the effects of daily oral doses of enclomiphene citrate (Androxal®) in comparison to transdermal testosterone on other hormones and markers in men with secondary hypogonadism. PATIENTS AND METHODS: This was a randomized, single blind, two-center phase II study to evaluate three different doses of enclomiphene citrate (6.25mg, 12.5mg and 25 mg Androxal®), versus AndroGel®, a transdermal testosterone, on 24-hour LH and TT in otherwise normal healthy men with secondary hypogonadism. Forty-eight men were enrolled in the trial (ITT Population), but 4 men had T levels >350 ng/dL at baseline. Forty-four men completed the study per protocol (PP population). All subjects enrolled in this trial had serum TT in the low range (<350 ng/dL) and had low to normal LH (<12 IU/L) on at least two occasions. TT and LH levels were assessed each hour for 24 hours to examine the effects at each of three treatment doses of enclomiphene versus a standard dose (5 grams) of transdermal testosterone (AndroGel). In the initial profile TT and LH were determined in a naïve population following a single initial oral or transdermal treatment (Day 1). This was contrasted to that seen after six weeks of continuous daily oral or transdermal treatment (Day 42). The pharmacokinetics of enclomiphene was performed in a select subpopulation. Serum samples were obtained over the course of the study to determine levels of various hormones and lipids. RESULTS: After six weeks of continuous use, the mean ± SD concentration of TT at Day 42 C0hrTT, was 604 ± 160 ng/dL for men taking the highest of dose of enclomiphene citrate (enclomiphene, 25 mg daily) and 500 ± 278 ng in those men treated with transdermal testosterone. These values were higher than Day 1 values but not different from each other (p = 0.23, T-test). All three doses of enclomiphene increased C0hrTT, CavgTT, CmaxTT, CminTT and CrangeTT. Transdermal testosterone also raised TT, albeit with more variability, and with suppressed LH levels. The patterns of TT over 24 hour period following six weeks of dosing could be fit to a non-linear function with morning elevations, mid-day troughs, and rising night-time levels. Enclomiphene and transdermal testosterone increased levels of TT within two weeks, but they had opposite effects on FSH and LH Treatment with enclomiphene did not significantly affect levels of TSH, ACTH, cortisol, lipids, or bone markers. Both transdermal testosterone and enclomiphene citrate decreased IGF-1 levels (p<0.05) but suppression was greater in the enclomiphene citrate groups. CONCLUSIONS: Enclomiphene citrate increased serum LH and TT; however, there was not a temporal association between the peak drug levels and the Cmax levels LH or TT. Enclomiphene citrate consistently increased serum TT into the normal range and increased LH and FSH above the normal range. The effects on LH and TT persisted for at least one week after stopping treatment.
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BACKGROUND: Reconstruction of the central aortic pressure wave from the noninvasive recording of the radial pulse with applanation tonometry has become a standard tool in the field of hypertension. It is not presently known whether recording the radial pulse on the dominant or the nondominant side has any effect on such reconstruction. METHOD: We carried out radial applanation tonometry on both forearms in young, healthy, male volunteers, who were either sedentary (n = 11) or high-level tennis players (n = 10). The purpose of including tennis players was to investigate individuals with extreme asymmetry between the dominant and nondominant upper limb. RESULTS: In the sedentary individuals, forearm circumference and handgrip strength were slightly larger on the dominant (mean +/- SD respectively 27.9 +/- 1.5 cm and 53.8 +/- 10 kg) than on nondominant side (27.3 +/- 1.6 cm, P < 0.001 vs. dominant, and 52.1 +/- 11 kg, P = NS). In the tennis players, differences between sides were more conspicuous (forearm circumference: dominant 28.0 +/- 1.7 cm nondominant 26.4 +/- 1.5 cm, P < 0.001; handgrip strength 61.4 +/- 10.8 vs. 53.4 +/- 9.7 kg, P < 0.001). We found that in both sedentary individuals and tennis players, the radial pulse had identical shape on both sides and, consequently, the reconstructed central aortic pressure waveforms, as well as derived indices of central pulsatility, were not dependent on the side where applanation tonometry was carried out. CONCLUSION: Evidence from individuals with maximal asymmetry of dominant vs. nondominant upper limb indicates that laterality of measurement is not a methodological issue for central pulse wave analysis carried out with radial applanation tonometry.
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The human auditory system is comprised of specialized but interacting anatomic and functional pathways encoding object, spatial, and temporal information. We review how learning-induced plasticity manifests along these pathways and to what extent there are common mechanisms subserving such plasticity. A first series of experiments establishes a temporal hierarchy along which sounds of objects are discriminated along basic to fine-grained categorical boundaries and learned representations. A widespread network of temporal and (pre)frontal brain regions contributes to object discrimination via recursive processing. Learning-induced plasticity typically manifested as repetition suppression within a common set of brain regions. A second series considered how the temporal sequence of sound sources is represented. We show that lateralized responsiveness during the initial encoding phase of pairs of auditory spatial stimuli is critical for their accurate ordered perception. Finally, we consider how spatial representations are formed and modified through training-induced learning. A population-based model of spatial processing is supported wherein temporal and parietal structures interact in the encoding of relative and absolute spatial information over the initial ∼300ms post-stimulus onset. Collectively, these data provide insights into the functional organization of human audition and open directions for new developments in targeted diagnostic and neurorehabilitation strategies.
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BACKGROUND: To test the hypothesis that intervals with superior beat-to-beat coronary artery repositioning precision exist in the cardiac cycle, to design a coronary MR angiography (MRA) methodology in response, and to ascertain its performance. METHODS: Coronary repositioning precision in consecutive heartbeats was measured on x-ray coronary angiograms of 17 patients and periods with the highest repositioning precision were identified. In response, the temporal order of coronary MRA pulse sequence elements required modification and the T2 -prep now follows (T2 -post) rather than precedes the imaging part of the sequence. The performance of T2 -post was quantitatively compared (signal-to-noise [SNR], contrast-to-noise [CNR], vessel sharpness) to that of T2 -prep in vivo. RESULTS: Coronary repositioning precision is <1 mm at peak systole and in mid diastole. When comparing systolic T2 -post to diastolic T2 -prep, CNR and vessel sharpness remained unchanged (both P = NS) but SNR for muscle and blood increased by 104% and 36% (both P < 0.05), respectively. CONCLUSION: Windows with improved coronary repositioning precision exist in the cardiac cycle: one in peak systole and one in mid diastole. Peak-systolic imaging necessitates a re-design of conventional coronary MRA pulse sequences and leads to image quality very similar to that of conventional mid-diastolic data acquisition but improved SNR. J. Magn. Reson. Imaging 2015;41:1251-1258. © 2014 Wiley Periodicals, Inc.
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Background: Previous studies reported an increase of mean platelet volume (MPV) in patients with acute ischemic stroke. However, its correlation with stroke severity has not been investigated. Moreover, studies on the association of MPV with functional outcome yielded inconsistent results. Methods: We included all consecutive ischemic stroke patients admitted to CHUV (Centre Hospitalier Universitaire Vaudois) Neurology Service within 24 h after stroke onset who had MPV measured on admission. The association of MPV with stroke severity (NIHSS score at admission and at 24 h) and outcome (Rankin Scale score at 3 and 12 months) was analyzed in univariate analysis. The chi(2) test was performed to compare the frequency of minor strokes (NIHSS score </=4) and good functional outcome (Rankin Scale score </=2) across MPV quartiles. The ANOVA test was used to compare MPV between stroke subtypes according to the TOAST classification. Student's two-tailed unpaired t test was performed to compare MPV between lacunar and nonlacunar strokes. MPV was generated at admission by the Sysmex XE-2100 automated cell counter (Sysmex Corporation, Kobe, Japan) from EDTA blood samples. Results: There was no significant difference in the frequency of minor strokes (p = 0.46) and good functional outcome (p = 0.06) across MPV quartiles. MPV was not associated with stroke severity or outcome in univariate analysis. There was no significant difference in MPV between stroke subtypes according to the TOAST classification (p = 0.173) or between lacunar and nonlacunar strokes (10.50 +/- 0.91 vs. 10.40 +/- 0.81 fl, p = 0.322). Conclusions: MPV, assessed within 24 h after ischemic stroke onset, is not associated with stroke severity or functional outcome.
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In C57Bl/6 strain mice vaccinated with radiation-attenuated cercariae of Schistosoma mansoni immune elimination of challenge parasites occurs in the lungs. Leococytes were recovered from the lungs of such mice by bronchoalveolar lavage and cultured in vitro with larval antigen; the profile of cytokines released was then analyzed. From 14 days after vaccination, BAL cultures contained infiltrating lymphocytes wich produced abundant quantitties of IFN-g and IL-3. Challenge of vaccinated mice resulted in a second influx of IFN-g nd IL-3- producing cells, earlier than after vaccination or in the appropriate contropls. Ablation studies revealed that CD4+ T cells were the source of IFN-g. The timing of cytokine production after vaccination, and challenge was coincident with the phases of macrophage activation previously reported. At no time could lymphocytes in BAL cultures to stimulated to proliferate with either larval Ag or mitogen, in contrast to splenocytes from the same mice. Furthermore, T cell growth factor activity was not detected in BAL cultures stimulated with Ag. We suggest that the lymphocytes recruited to the lungs are memory/effector cells, When Ag. released challenge schistosomula is presented to these cells, they respond by secreting cytokines wich mediate the formation of cellular aggregates around the parasites, blocking their onward migration.
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After the acute hyperergic phase of schistosomal infection, the chronic phase of the disease corresponds to the estabilishment of a relative equilibrium between the host and the parasite. This involves: (1) A shift from the predominance of the TH2 response observed in the acute phase, to the predominance of the TH1 response in the chronic phase of the disease, with modification of lymphokine and immunoglobulin secretions patterns. (2) Redistribution of hosts responses to parasite, with predominance of systemic controls in the acute phase, and a shift towards local tissue responses in the chronic phase. This redistribution relieves the hyperergic responses involving the whole body of the host, and delimits cellular and molecular reactions to parasites to only those tissues that are directly involved by the adult parasites and their eggs. Mobilization of eosinophil granulocytes in schistosomal periovular granulomas is one of examples of this redistribution.
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This study investigated the direction of effects of temporal and downward social comparisons on self-rated health in very old age. Self-rated health can either reinforce or hinder comparison processes. In the framework of the Swiss Interdisciplinary Longitudinal Study on the Oldest Old, individuals aged 80 to 84 at baseline were interviewed and followed longitudinally for 5 years. Multilevel analyses were used to test the relative importance of temporal and social comparisons on self-rated health evaluations synchronically and diachronically (with a time lag of 12 to 18 months) as well as the direction of these relative influences. Results indicate that (a) at the synchronic level, continuity temporal comparisons have more impact than downward social comparisons on self-rated health; (b) both types of comparison had an independent and positive effect on self-rated health at the diachronic level; (c) self-rated health has an independent synchronic effect on both types of comparison and an independent diachronic effect in temporal comparison.
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Salivary glad lysates of the sand fly Lutzomia longipalpis have been shown to enhance the infectivity of Leishmania in mice. As shown herein, the simultaneous inoculation of Leishmania chagasi stationary-phase promastigotes and L. longipalpis salivary gland by the intradermal route in a group of mongrel dogs induced a statistically significant eosinophilia, in relation to dogs inoculated with Leishmania or with salivary gland lysate only. These dogs had no evidence of infection, in spite of the infectivity of the promastigotes when inoculated by the intravenous route.
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The spatial and temporal distribution of anopheline larvae was studied in two coastal malarious areas of Sucre, State, Venezuela. Seven habitat types were sampled in the village of Guayana and eight species of Anopheles were collected. Anopheles aquasalis was the predominant species collected and was most abundant in the brackish marsh habitat (71 larvae per 100 samples). It was most abundant during the rainy season. At the second location, Santa F e, six habitat types were sampled and four anopheline species were collected. Habitats where An. aquasalis was most abundant were temporary freshwater ponds (34 larvae per 100 samples) and mangroves (10.5 larvae per 100 samples). At this location it was also most abundant in the rainy season. During the dry season it was collected in small numbers in river pools (1.3 larvae per 100 samples) along with large numbers of An. pseudopunctipennis (479 larvae per 100 samples). Larval control could be an important component of the malaria control program because major habitats could be defined and presence and abundance of larvae was limited to specific times of year.
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Interaural intensity and time differences (IID and ITD) are two binaural auditory cues for localizing sounds in space. This study investigated the spatio-temporal brain mechanisms for processing and integrating IID and ITD cues in humans. Auditory-evoked potentials were recorded, while subjects passively listened to noise bursts lateralized with IID, ITD or both cues simultaneously, as well as a more frequent centrally presented noise. In a separate psychophysical experiment, subjects actively discriminated lateralized from centrally presented stimuli. IID and ITD cues elicited different electric field topographies starting at approximately 75 ms post-stimulus onset, indicative of the engagement of distinct cortical networks. By contrast, no performance differences were observed between IID and ITD cues during the psychophysical experiment. Subjects did, however, respond significantly faster and more accurately when both cues were presented simultaneously. This performance facilitation exceeded predictions from probability summation, suggestive of interactions in neural processing of IID and ITD cues. Supra-additive neural response interactions as well as topographic modulations were indeed observed approximately 200 ms post-stimulus for the comparison of responses to the simultaneous presentation of both cues with the mean of those to separate IID and ITD cues. Source estimations revealed differential processing of IID and ITD cues initially within superior temporal cortices and also at later stages within temporo-parietal and inferior frontal cortices. Differences were principally in terms of hemispheric lateralization. The collective psychophysical and electrophysiological results support the hypothesis that IID and ITD cues are processed by distinct, but interacting, cortical networks that can in turn facilitate auditory localization.
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Rats experimentally infected with Trypanosoma cruzi Y strain exhibited hypertrophy of the submandibular gland at 18 days after infection.SDS-PAGE of infected rats saliva revealed the presence of an additional band with an apparent molecular weight of about 13KDa. Electrophoresis of protein salivaand immunochemical analysis with antibody against rat cystatin S confirmed that the protein was identical to that induced by beta adrenergic stimulation.
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The benefit of bevacizumab (Bv) has been shown in different tumors including colorectal cancer, renal cancer, pulmonary non-small cell cancer and also breast cancer. However to date, there is no established test evaluating the angiogenic status of a patient and monitoring the effects of anti-angiogenic treatments. Tumor angiogenesis is the result of a balance between multiple pro- and anti¬angiogenic molecules. There is very little published clinical data exploring the impact of the anti-angiogenic therapy on the different angiogenesis-related molecules and the potential role of these molecules as prognostic or predictive factors.