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61.
Alfredo García-Layana Sergio Recalde Maria Hernandez Maximino J. Abraldes Joo Nascimento Emiliano Hernndez-Galilea Begoa Olmedilla-Alonso Jose Juan Escobar-Barranco Miguel Angel Zapata Rufino Silva Mariana Caballero Arredondo María Carmen Lopez-Sabater Silvia Mendez-Martínez Nieves Pardias-Barn Pilar Calvo Patricia Fernndez-Robredo 《Nutrients》2021,13(4)
The purpose of this study is evaluate the efficacy and safety of medicinal products containing the original Age-Related Eye Disease group (AREDS) formulation at doses approved in Europe (EU, control group; n = 59) with a product that adds DHA, lutein, zeaxanthin, resveratrol and hydroxytyrosol to the formula (intervention group; n = 50). This was a multicenter, randomized, observer-blinded trial conducted in patients aged 50 years or older diagnosed with unilateral exudative Age related Macular Degeneration AMD. At month 12, the intervention did not have a significant differential effect on visual acuity compared with the control group, with an estimated treatment difference in Early Treatment Diabetic Retinopathy Study (ETDRS) of −1.63 (95% CI −0.83 to 4.09; p = 0.192). The intervention exhibited a significant and, in most cases, relevant effect in terms of a reduction in some inflammatory cytokines and a greater improvement in the fatty acid profile and serum lutein and zeaxantin concentration. In patients with unilateral wet AMD, the addition of lutein, zeaxanthin, resveratrol, hydroxytyrosol and DHA to the AREDS EU recommended doses in the short-term did not have a differential effect on visual acuity compared to a standard AREDS EU formula but, in addition to improving the fatty acid profile and increasing carotenoid serum levels, may provide a beneficial effect in improving the proinflammatory and proangiogenic profile of patients with AMD. 相似文献
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Eduardo Palomares Jos C. Bellido Angel L. Morales Antonio J. Nieto Jose M. Chicharro Publio Pintado 《Optimal control applications & methods.》2021,42(1):216-235
This article presents an optimal control strategy (OCS) for semiactive vehicle suspensions with road profile sensors. The suspension is modeled as a quarter‐car model with a magnetorheological (MR) damper. The OCS main objective is to minimize the fourth‐power acceleration of the sprung mass. In addition, three pointwise constraints of the model are taken into account when the optimal control problem is solved: suspension travel limits (upper and lower) and tyre vertical force. In order to deal with a large number of constraints, we implement the gradient optimization method based on the method of moving asymptotes routine, which shows very good performance reaching optimal controls while satisfying the constrains. The solution has been compared with two passive MR damper configurations (low and high damping) as well as Skyhook and Balance control strategies for three different road inputs. Results show that OCS fulfills the constraints and reduces the sprung mass acceleration peak and the root‐mean‐quad acceleration up to 59% , in comparison to passive strategies. 相似文献
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Yuki Matsushita Angel Ka Yan Chu Wanida Ono Joshua D Welch Noriaki Ono 《Journal of bone and mineral research》2021,36(6):1145-1158
Bone marrow houses a multifunctional stromal cell population expressing C-X-C motif chemokine ligand 12 (CXCL12), termed CXCL12-abundant reticular (CAR) cells, that regulates osteogenesis and adipogenesis. The quiescent pre-adipocyte-like subset of CXCL12+ stromal cells (“Adipo-CAR” cells) is localized to sinusoidal surfaces and particularly enriched for hematopoiesis-supporting cytokines. However, detailed characteristics of these CXCL12+ pre-adipocyte-like stromal cells and how they contribute to marrow adipogenesis remain largely unknown. Here we highlight CXCL12-dependent physical coupling with hematopoietic cells as a potential mechanism regulating the adipogenic potential of CXCL12+ stromal cells. Single-cell computational analyses of RNA velocity and cell signaling reveal that Adipo-CAR cells exuberantly communicate with hematopoietic cells through CXCL12-CXCR4 ligand-receptor interactions but do not interconvert with Osteo-CAR cells. Consistent with this computational prediction, a substantial fraction of Cxcl12-creER+ pre-adipocyte-like cells intertwines with hematopoietic cells in vivo and in single-cell preparation in a protease-sensitive manner. Deletion of CXCL12 in these cells using Col2a1-cre leads to a reduction of stromal-hematopoietic coupling and extensive marrow adipogenesis in adult bone marrow, which appears to involve direct conversion of CXCL12+ cells to lipid-laden marrow adipocytes without altering mesenchymal progenitor cell fates. Therefore, these findings suggest that CXCL12+ pre-adipocyte-like marrow stromal cells prevent their premature differentiation by maintaining physical coupling with hematopoietic cells in a CXCL12-dependent manner, highlighting a possible cell-non-autonomous mechanism that regulates marrow adipogenesis. © 2021 American Society for Bone and Mineral Research (ASBMR). 相似文献
67.
Isolation of putative dengue virus receptor molecules by affinity chromatography using a recombinant E protein ligand 总被引:3,自引:0,他引:3
Nucleotide sequences coding for the full-length envelope (E) glycoprotein gene of dengue virus type 4 was amplified using an RT-PCR method from infected C6/36 cells and cloned into pPROEx-Hta expression vector. The expression of the recombinant E protein in Escherichia coli was confirmed by Western blot using a polyclonal anti-dengue polyclonal antibody. The His-tagged fusion protein was obtained from the bacterial cellular extracts in almost pure form by immobilized metal affinity chromatography and the recombinant protein retained its ability to bind to 40 and 45 kDa proteins, previously described as putative receptors for dengue virus in C6/36 cells. To purify the 40 and 45 kDa molecules, a total protein extract from C6/36 cells was passed through an affinity chromatography column using immobilized recombinant E protein. After washing with isotonic buffer, elution was accomplished using a high salt buffer. The two proteins obtained, with molecular weights of 40 and 45 kDa, were recognized by dengue 4 virus, in virus overlay protein binding assay. This procedure allows further characterization of molecules that could be involved in dengue binding and entry. 相似文献
68.
Self-rated health and mortality in the NHANES-I Epidemiologic Follow-up Study. 总被引:28,自引:7,他引:21 下载免费PDF全文
The ability of self-rated health status to predict mortality was tested with data from the National Health and Nutrition Examination Survey (NHANES-I) Epidemiologic Follow-Up Study (NHEFS), conducted from 1971-84. The sample consists of adult NHANES-I respondents ages 25-74 years (N = 6,440) for whom data from a comprehensive physical examination at the initial interview and survival status at follow-up are available. Self-rated health consists of the response to the single item, "Would you say your health in general is excellent, very good, good, fair, or poor?" Proportional hazards analyses indicated that, net of its association with medical diagnoses given in the physical examination, demographic factors, and health related behaviors, self-rated health at Time 1 is associated with mortality over the 12-year follow-up period among middle-aged males, but not among elderly males or females of any age. 相似文献
69.
Ramn Alvarenga Ariadna Gonzlez del Angel Victoria del Castillo Silvestre García de la Puente Irene Mauln Alessandra Carnevale 《American journal of medical genetics. Part A》1995,56(2):173-175
Several patients with the Silver-Russell syndrome (SRS) attending our Genetics Clinic were diagnosed as having persistent metabolic acidosis. Since this abnormality has not been reported previously in the SRS, we reexamined 33 SRS patients to evaluate the frequency and type of metabolic acidosis, the clinical and laboratory findings, and the growth pattern in SRS patients with and without metabolic acidosis. Among them, 14 had a consistent decrease in HCO levels. Renal studies in acidotic patients showed urine pH of 5.8 and 24 h urine calcium of <2.4 mg/kg/24 h; serum creatinine, excretion of glucose, and aminoacids were normal, as were renal ultrasound and excretory urography findings. These data supported the diagnosis of renal tubular acidosis, probably type II; the patients were treated with oral bicarbonate and acidosis was corrected successfully. Clinical manifestations were similar in acidotic and non-acidotic patients. The nutritional indices at diagnosis and at last evaluation (at least 8 months after diagnosis) were abnormally low in all patients; however, acidotic patients, treated with bicarbonate, showed an improvement of nutritional status particularly in the weight/height index, although the difference between groups after follow-up did not reach statistical significance. We suggest that metabolic acidosis due to renal tubular acidosis, probably type II, may occur in children with the SRS and should be looked for and treated in all patients. © 1995 Wiley-Liss, Inc. 相似文献
70.
Francisco Cano Angela Delucchi Eduardo Wolff Eugenio Rodriguez Angel Fuentes 《Pediatric nephrology (Berlin, Germany)》1995,9(5):606-608
A 6-month protocol of oral pulse calcitriol was used in nine uraemic children (2–14 years old) on dialysis who presented with renal osteodystrophy. Calcitriol was administered twice a week, 4 g per dose for patients over 30 kg and 3g for patients less than 30 kg. Plasma levels of parathyroid hormone, calcium, phosphorus and alkaline phosphatase were carefully controlled during the study. Parathyroid hormone levels decreased by 68% and 56% by the 2nd and 6th months of treatment in seven patients, while they remained unchanged in two patients with focal segmental glomerulosclerosis and massive proteinuria. Eight hypercalcaemic episodes from 77 determinations were observed, all of them recovered after 1 week of vitamin D withdrawal. We conclude that oral calcitriol pulse therapy is a good alternative for renal osteodystrophy in uraemic children. Careful monitoring of plasma parathyroid hormone and calcium is needed during follow-up when using this approach in paediatric patients. 相似文献