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961.
Faiez Zannad Jacqueline Alikhaani Sadegh Alikhaani Javed Butler Jason Gordon Klaus Jensen Rani Khatib Lorenzo Mantovani Robin Martinez Wanda F. Moore Masahiro Murakami Lothar Roessig Norman Stockbridge Harriette G.C. Van Spall Clyde Yancy John A. Spertus 《European journal of heart failure》2023,25(4):478-487
There are many consequences of heart failure (HF), including symptoms, impaired health-related quality of life (HRQoL), and physical and social limitations (functional status). These have a substantial impact on patients' lives, yet are not routinely captured in clinical trials. Patient-reported outcomes (PROs) can quantify patients' experiences of their disease and its treatment. Steps can be taken to improve the use of PROs in HF trials, in regulatory and payer decisions, and in patient care. Importantly, PRO measures (PROMs) must be developed with involvement of patients, family members, and caregivers from diverse demographic groups and communities. PRO data collection should become more routine not only in clinical trials but also in clinical practice. This may be facilitated by the use of digital tools and interdisciplinary patient advocacy efforts. There is a need for standardization, not only of the PROM instruments, but also in procedures for analysis, interpretation and reporting PRO data. More work needs to be done to determine the degree of change that is important to patients and that is associated with increased risks of clinical events. This ‘minimal clinically important difference’ requires further research to determine thresholds for different PROMs, to assess consistency across trial populations, and to define standards for improvement that warrant regulatory and reimbursement approvals. PROs are a vital part of patient care and drug development, and more work should be done to ensure that these measures are both reflective of the patient experience and that they are more widely employed. 相似文献
962.
Alexandra Potvin-Desrochers Alisha Atri Alejandra Martinez Moreno Caroline Paquette 《The European journal of neuroscience》2023,57(1):163-177
Freezing of gait (FOG) is a debilitating motor symptom of Parkinson's disease (PD). Although PD dopaminergic medication (L-DOPA) seems to generally reduce FOG severity, its effect on neural mechanisms of FOG remains to be determined. The purpose of this study was to quantify the effect of L-DOPA on brain resting-state functional connectivity in individuals with FOG. Functional magnetic resonance imaging was acquired at rest in 30 individuals living with PD (15 freezers) in the ON- and OFF- medication state. A seed-to-voxel analysis was performed with seeds in the bilateral basal ganglia nuclei, the thalamus and the mesencephalic locomotor region. In freezers, medication-state contrasts revealed numerous changes in resting-state functional connectivity, not modulated by L-DOPA in non-freezers. In freezers, L-DOPA increased the functional connectivity between the seeds and regions including the posterior parietal, the posterior cingulate, the motor and the medial prefrontal cortices. Comparisons with non-freezers revealed that L-DOPA generally normalizes brain functional connectivity to non-freezers levels but can also increase functional connectivity, possibly compensating for dysfunctional networks in freezers. Our findings suggest that L-DOPA could contribute to a better sensorimotor, attentional, response inhibition and limbic processing to prevent FOG when triggers are encountered but could also contribute to FOG by interfering with the processing capacity of the striatum. This study shows that levodopa taken to control PD symptoms induces changes in functional connectivity at rest, in freezers only. Increases (green) in functional connectivity of GPe, GPi, putamen and thalamus with cognitive, sensorimotor and limbic cortical regions of the Interference model (blue) was observed. Our results suggest that levodopa can normalize connections similar to non-freezers or increases connectivity to compensate for dysfunctional networks. 相似文献
963.
Marcela Chisté Elena Vrotsos Carlos Zamora Antonio Martinez 《Annals of diagnostic pathology》2013,17(3):295-297
Chronic lymphocytic leukemia/small lymphocytic lymphoma is a neoplasm composed of monomorphic small B lymphocytes in the peripheral blood, bone marrow, spleen, and lymph nodes, forming proliferation centers in tissue infiltrates (Muller-Hermelink HK, Montserrat E, Catovsky D, et al. Chronic lymphocytic leukaemia/small lymphocytic lymphoma, in Swerdlow SH (ed). WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues. Lyon, France, International Agency for Research on Cancer, 2008, pp. 180-182). We report a case of a 77-year-old man with a medical history of chronic lymphocytic leukemia who presented with worsening chest pain over 8 weeks. Imaging studies revealed severe aortic stenosis and moderate mitral regurgitation. He subsequently underwent minimally invasive aortic valve replacement and mitral repair at our institution. Grossly, the specimen consisted of a trileaflet valve with multiple yellow-white focally hemorrhagic and calcified nodules over its surface. Histologically, a lymphocytic infiltrate composed of monotonous small cells with scant cytoplasm was seen as well as calcification and fibrosis. Immunohistochemical stains were positive for CD20, PAX5, CD5, and CD23. To our knowledge, this is the first reported case of an immunohistochemically documented chronic lymphocytic leukemia/small lymphocytic lymphoma to involve a cardiac valve. 相似文献
964.
Edgar Toschi-Dias Ivani C. Trombetta Valdo José Dias da Silva Cristiane Maki-Nunes Maria Janieire N. N. Alves Luciana F. Angelo Felipe X. Cepeda Daniel G. Martinez Carlos Eduardo Negrão Maria Urbana P. B. Rondon 《European journal of applied physiology》2013,113(3):671-679
Previous investigations show that metabolic syndrome (MetSyn) causes sympathetic hyperactivation. Symptoms of anxiety and mood disturbance (AMd) provoke sympatho-vagal imbalance. We hypothesized that AMd would alter even further the autonomic function in patients with MetSyn. Twenty-six never-treated patients with MetSyn (ATP-III) were allocated to two groups, according to the levels of anxiety and mood disturbance: (1) with AMd (MetSyn + AMd, n = 15), and (2) without AMd (MetSyn, n = 11). Ten healthy control subjects were also studied (C, n = 10). AMd was determined using quantitative questionnaires. Muscle sympathetic nerve activity (MSNA, microneurography), blood pressure (oscillometric beat-to-beat basis), and heart rate (ECG) were measured during a baseline 10-min period. Spectral analysis of RR interval and systolic arterial pressure were analyzed, and the power of low (LF) and high (HF) frequency bands were determined. Sympatho-vagal balance was obtained by LF/HF ratio. Spontaneous baroreflex sensitivity (BRS) was evaluated by calculation of α-index. MSNA was greater in patients with MetSyn + AMd compared with MetSyn and C. Patients with MetSyn + AMd showed higher LF and lower HF power compared with MetSyn and C. In addition, LF/HF balance was higher in MetSyn + AMd than in MetSyn and C groups. BRS was decreased in MetSyn + AMd compared with MetSyn and C groups. Anxiety and mood disturbance alter autonomic function in patients with MetSyn. This autonomic dysfunction may contribute to the increased cardiovascular risk observed in patients with mood alterations. 相似文献
965.
966.
M.B.M. Linhares C.M. Gaspardo L.O. Souza B.O. Valeri F.E. Martinez 《Brazilian journal of medical and biological research》2014,47(6):527-532
Sucrose solution is recommended as relevant pain relief management in neonates duringacute painful procedures; however, only a few studies have analyzed the potentiallyadverse effects of sucrose administration to preterm neonates. The goal of this studywas to examine the potential side effects of sucrose for pain relief in preterminfants, assessing feeding and weight gain during hospitalization and their feedingpatterns postdischarge. The study sample consisted of 43 preterm neonates dividedinto two groups: a sucrose group (SG, n=18) and a control group (CG, n=25) in whichno sucrose was administered. The SG received 0.5 mL/kg 25% oral sucrose for 2 minprior to all acute painful procedures during three consecutive days. A prospectivereview of medical charts was performed for all samples. The study was done prior toimplementation of the institutional sucrose guidelines as a routine service, andfollowed all ethical requirements. There were no statistically significantdifferences between groups in terms of weight gain, length of stay with orogastrictubes, and parenteral feeding. Postdischarge, infant nutritional intake includedfeeding human milk to 67% of the SG and 74% of the CG. There were no statisticallysignificant differences between groups regarding human milk feeding patternspostdischarge. Neonate feeding patterns and weight gain were unaffected following theshort-term use of sucrose for pain relief. 相似文献
967.
968.
D Werner F Martinez F Roch-Ramel 《The Journal of pharmacology and experimental therapeutics》1990,252(2):792-799
The transport of urate and p-aminohippurate (PAH) across the pig renal brush border membrane was investigated using membrane vesicles. Compared to a pH equilibrium condition (pHin = 7.4; pHout = 7.4), an outwardly directed OH- gradient (pHin = 7.4; pHout = 5.8) stimulated markedly both lactate and pyrazinoate uptake with overshoots exceeding 2 times that of the steady state. In contrast, neither OH-/urate nor OH-/PAH exchange could be demonstrated. An outwardly directed Cl- gradient (Cl-in = 100 mM; Cl-out = 16.7 mM) increased 2.6-fold 15-sec PAH uptake compared to Cl- equilibrium (Cl-in = Cl-out = 100 mM) but this stimulation was due solely to an effect of membrane potential. Creation of an electropositive intravesicular space, by imposing an inwardly directed K+ gradient (K+in = 0 mM; K+out = 100 mM) in the presence of valinomycin, was very effective to drive uphill PAH and urate accumulation compared to the control condition (no valinomycin). Four-second potential-stimulated PAH uptake was saturable (Km, 0.8 mM; Vmax, 1.7 nmol/mg of protein x 4 sec). Different organic anions cis-inhibited both 4-sec potential-stimulated PAH and urate uptakes in a similar fashion. PAH and urate, moreover, decreased each other's accumulation. In countertransport experiments, PAH and urate uptakes were not significantly stimulated by trans-unlabeled substrate. These results are consistent with the presence, in the pig renal brush border membrane, of a mediated secretory pathway common for urate and PAH, which could be facilitated by the potential difference existing in vivo across the luminal membrane of the proximal tubule. 相似文献
969.
Wallerian degeneration is a very well described phenomenon in the vertebrate nervous system. In arthropods, and especially in crustaceans, nerve fiber degeneration has not been described extensively. In addition, literature shows that the events do not follow the same patterns as in vertebrates. In this study we report, by qualitative and quantitative ultrastructural analyses, the features and time course of the protocerebral tract degeneration following extirpation of the optic stalk. No remarkable changes were observed seven days after lesion. After 28 days the protocerebral tracts presented apparently preserved small and large diameter axons and some degenerating medium axons, with irregular contours and empty-looking aspect of the axoplasm. Forty days after the ablation of the optic stalks, both small (type I) and medium (type II and III) axons revealed signs of partial or total degeneration, but large nerve fibers (type IV) were still intact. After 45 days, the tract showed signs of advanced stage of degeneration and, apart from large axons, normal-looking fibers were almost absent. At these 3 last time points, degenerating axons displayed different electron densities and aspects, probably correlating to different onset times of the process. In addition, cells with granules in their cytoplasm, possibly hemocytes, were quite distinct, especially at 40 and 45 days after axotomy. These cells might share with glial cells the function of phagocytosis of cellular debris during the protocerebral tract degeneration. Quantitative analysis showed that the number of degenerating fibers increased significantly from 28 to 40 days after lesion, whereas the number of normal fibers decreased accordingly. Measurements of cross-sectional areas of normal and degenerating axons showed that types II and III (medium) start to degenerate before type I (small). Type IV (large) axons do not degenerate, even after 40 days. Therefore, we can conclude that degeneration in these afferent fibers starts late after axotomy, but proceeds at a faster rate afterwards until the complete degeneration of small and medium axons. 相似文献
970.