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61.
Impact of Calcium and Two Doses of Vitamin D on Bone Metabolism in the Elderly: A Randomized Controlled Trial
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Maya Rahme Sima Lynn Sharara Rafic Baddoura Robert H Habib Georges Halaby Asma Arabi Ravinder J Singh Moustapha Kassem Ziyad Mahfoud Maha Hoteit Rose T Daher Darina Bassil Karim El Ferkh Ghada El‐Hajj Fuleihan 《Journal of bone and mineral research》2017,32(7):1486-1495
The optimal dose of vitamin D to optimize bone metabolism in the elderly is unclear. We tested the hypothesis that vitamin D, at a dose higher than recommended by the Institute of Medicine (IOM), has a beneficial effect on bone remodeling and mass. In this double‐blind trial we randomized 257 overweight elderly subjects to receive 1000 mg of elemental calcium citrate/day, and the daily equivalent of 3750 IU/day or 600 IU/day of vitamin D3 for 1 year. The subjects’ mean age was 71 ± 4 years, body mass index 30 ± 4 kg/m2, 55% were women, and 222 completed the 12‐month follow‐up. Mean serum 25 hydroxyvitamin D (25OHD) was 20 ng/mL, and rose to 26 ng/mL in the low‐dose arm, and 36 ng/mL in the high‐dose arm, at 1 year (p < 0.05). Plasma parathyroid hormone, osteocalcin, and C‐terminal telopeptide (Cross Laps) levels decreased significantly by 20% to 22% in both arms, but there were no differences between the two groups for any variable, at 6 or 12 months, with the exception of serum calcitriol, which was higher in the high‐dose group at 12 months. Bone mineral density (BMD) increased significantly at the total hip and lumbar spine, but not the femoral neck, in both study arms, whereas subtotal body BMD increased in the high‐dose group only, at 1 year. However, there were no significant differences in percent change BMD between the two study arms at any skeletal site. Subjects with serum 25OHD <20 ng/mL and PTH level >76 pg/mL showed a trend for higher BMD increments at all skeletal sites, in the high‐dose group, that reached significance at the hip. Adverse events were comparable in the two study arms. This controlled trial shows little additional benefit in vitamin D supplementation at a dose exceeding the IOM recommendation of 600 IU/day on BMD and bone markers, in overweight elderly individuals. © 2017 American Society for Bone and Mineral Research. 相似文献
62.
Narjara Gonzalez Suarez Yuniel Fernandez-Marrero Sima Torabidastgerdooei Borhane Annabi 《Nutrients》2022,14(5)
Background: Triple-negative breast cancer (TNBC) cells secretome induces a pro-inflammatory microenvironment within the adipose tissue, which hosts both mature adipocytes and adipose-derived mesenchymal stem/stromal cells (ADMSC). The subsequent acquisition of a cancer-associated adipocyte (CAA)-like phenotype is, however, unknown in ADMSC. While epidemiological studies suggest that consuming a polyphenol-rich diet reduces the incidence of some obesity-related cancers, the chemopreventive impact of green tea-derived epigallocatechin-3-gallate (EGCG) against the cues that trigger the CAA phenotype remain undocumented in ADMSC. Methods: Human ADMSC were exposed to human TNBC-derived MDA-MB-231 conditioned media (TNBC cells secretome) supplemented or not with EGCG. Differential gene expression was assessed through RNA-Seq analysis and confirmed by RT-qPCR. Protein expression levels and the activation status of signal transduction pathways mediators were determined by Western blotting. ADMSC chemotaxis was assessed by a real-time cell migration assay. Results: The TNBC cells secretome induced in ADMSC the expression of the CAA cytokines CCL2, CCL5, IL-1β, and IL-6, and of immunomodulators COX2, HIF-1α, VEGFα, and PD-L1. The epithelial-to-mesenchymal biomarker Snail was found to control the CAA phenotype. EGCG inhibited the induction of CAA genes and the activation status of Smad2 and NF-κB. The induced chemotactic response was also inhibited by EGCG. Conclusion: The induction of an inflammatory and CAA-like phenotype in ADMSC can be triggered by the TNBC cells secretome, while still efficiently prevented by diet-derived polyphenols. 相似文献
63.
Jahan-Bakhsh Raoof Mohammad Ali Karimi Sayed Reza Hosseini Sima Mangelizadeh 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2010,638(1):33-38
In this work, m-toluidine is electropolymerized at the surface of carbon paste electrode using consecutive cyclic voltammetry in 20 mM monomer aqueous solution in the presence of 6 mM cetyltrimethyl ammonium bromide (CTAB) as surfactant. Then transition metal of nickel is incorporated into the polymer by electrodepositing of Ni (II) from 1.5 M NiSO4 acidic solution using chronoamperometry technique (−1.0 V versus Ag|AgCl|KCl (3 M) for 15 min). In alkaline medium (i.e. NaOH 0.1 M) a good redox behavior of Ni (III)/Ni (II) couple at the surface of Ni/poly (m-toluidine) modified carbon paste electrode (Ni/PMT/MCPE) in the absence and presence of CTAB (Ni/CTAB-PMT/MCPE) can be observed. Electrocatalytic oxidation of methanol has been studied on Ni/PMT/MCPE and Ni/CTAB-PMT/MCPE. The results show that CTAB significantly enhances the catalytic efficiency of nickel particles on the oxidation of methanol in aqueous alkaline media. Moreover, the effects of various parameters such as concentration of CTAB, concentration of methanol, electrodepositing time, film thickness and monomer concentration on the electrooxidation of methanol as well as long-term stability of the Ni/CTAB-PMT/MCPE have also been investigated. This polymeric modified electrode can oxidize the methanol with high current density (over 40 mA cm−2). 相似文献
65.
Farzaneh P Ebtekar M Hassan ZM Rafati S 《Iranian journal of allergy, asthma, and immunology》2003,2(2):89-93
Although thorough studies on the immune reponse to rubella have been performed, less attention has been given to the cellular mechanism and mediators that shape the process. Specifically, information concerning the nature ofcytokine patterns involved in the immune response to Rubella vaccination is not avaliable. This study deals with cytokine production patterns of spleen cells from Balb/c mice following vaccination with the Takahashi strain of Rubella vaccine. Mice were injected intraperitonealy with Rubella virus and PBS and 7, 10 or 14 days later, spleen cells were separated and cultured with varying doses of virus, con A or only the medium. ELISA assays were performed on supernatants for measurement of IL-4, INF-gamma and IL-5. LTT (Lymphocyte Transformation Test) was also performed. The data indicate variation in cytokine patterns during the time periods after vaccination. On day 7 a type 1 pattern was observed. The LTT response was also indicative of CMI (Cell Mediated Immunity) response on the 7th and 14th days while a transient suppression on day 10 was observed. These results indicate a time dependent cytokine response with variation ultimately leading o a dominant type 1 (Ti) cytokine response. 相似文献
66.
Cohen AD Grunwald MH Avinoach I Halevy S 《Journal of the American Academy of Dermatology》2003,49(4):729-730
Trichodiscomas are hamartomas of the hair disk and appear as multiple, firm, well-circumscribed papules measuring a few millimeters. In most cases, trichodiscomas are distributed on the face and neck. Trichodiscomas may occur as isolated tumors or in association with other follicular tumors. In some cases, multiple trichodiscomas appear in association with fibrofolliculomas or acrochordons. We herein describe multiple agminated trichodiscomas in the earlobe. 相似文献
67.
Antisense deoxyoligonucleotides or antibodies to murine MD-1 inhibit rejection of allogeneic and xenogeneic skin grafts in C3H mice 总被引:4,自引:0,他引:4
BACKGROUND: Altered expression of murine MD-1, a molecule controlling expression of members of the interleukin (IL)-1 receptor family of signaling proteins, regulates antigen-presenting cell-induced alloreactions. We investigated the effect of treatment with antisense deoxyoligonucleotides or antibodies to MD-1 in vivo on allogeneic and xenogeneic skin graft survival and the immune responses in transplanted mice. METHODS: C3H mice received C57BL/6 or Lewis rat skin grafts, followed by i.v. injections of anti-MD-1 antibody or antisense oligonucleotides or control reagents at 48-hr intervals. Survival was monitored. In separate studies, mice were sacrificed at 5-day intervals. Serum was analyzed for circulating MD-1 antigen, and peritoneal cells for surface expression of MD-1. The proliferative and cytolytic response of lymphocytes harvested from treated animals and restimulated in vitro with allo- or xenogeneic cells, and the cytokines produced, was measured. Graft histology was assessed at 11 days after transplantation. RESULTS: Treatment with anti-MD-1 oligonucleotides or antibodies suppressed rejection of both xeno- and allogeneic grafts, decreased induction of graft-specific cytotoxic T cells, increased production of type-2 cytokines (IL-4 and IL-10), and decreased production of type-1 cytokines (IL-2 and interferon-gamma). Serum levels of MD-1 were suppressed, as was expression of MD-1 on the surface of antigen-presenting cells. Grafts from MD-1-treated mice showed little lymphocyte infiltration, and no signs of graft necrosis. CONCLUSION: Our data suggest a critical in vivo role for MD-1 expression in regulating graft rejection, as well as in the concomitant sensitization of T cells and their cytokine production profile, which parallels the rejection response. 相似文献
68.
CDH1 mutations are present in both ductal and lobular breast cancer, but promoter allelic variants show no detectable breast cancer risk 总被引:9,自引:0,他引:9
69.
Xu G Pierson CR Murakawa Y Sima AA 《Journal of neuropathology and experimental neurology》2002,61(2):164-175
Cytoskeletal protein expression in sensory neurons and sciatic nerve axonal growth were examined in type 1 diabetic BB/Wor rats after sciatic nerve crush injury. Diabetic male rats were subjected to sciatic nerve crush at 6 wk of diabetes. L4 and L5 dorsal root ganglia (DRG) mRNA expression of low and medium molecular weight neurofilaments (NF-L, NF-M), betaII- and betaIII-tubulin as well as protein expression of NF-L, NF-M, and beta-tubulin were examined at various time points following crush injury and compared with age- and sex-matched non-diabetic BB/Wor rats. Steady state mRNA expression of NF-L, NF-M, betaII- and betaIII-tubulin were decreased in diabetic DRG. NF-L and NF-M proteins were also decreased in DRG of uncrushed diabetic animals. After crush injury, betaII- and betaIII-tubulin mRNA were upregulated in control animals at day 2 and day 6, respectively, and beta-tubulin protein showed similarly increased expression after crush injury, while such upregulations did not occur in diabetic animals. Conversely, mRNA and protein expressions of NF-L, NF-M were downregulated to a lesser extent in diabetic animals compared to control rats. These changes were associated with impaired axonal elongation and caliber growth of regenerating fibers in diabetic rats. We propose that upregulation of tubulin has a negative feedback on NF expression in response to nerve injury, as seen in control rats. The absence of this upregulation in diabetic animals may impair its regulatory effect on NF expression and contribute to perturbed nerve regeneration seen in diabetic nerve. 相似文献
70.
To explore mechanisms underlying central nervous system (CNS) complications in diabetes, we examined hippocampal neuronal apoptosis and loss, and the effect of C-peptide replacement in type 1 diabetic BB/W rats. Apoptosis was demonstrated after 8 months of diabetes, by DNA fragmentation, increased number of apoptotic cells, and an elevated ratio of Bax/Bcl-xL, accompanied by reduced neuronal density in the hippocampus. No apoptotic activity was detected and neuronal density was unchanged in 2-month diabetic hippocampus, whereas insulin-like growth factor (IGF) activities were impaired. In type 1 diabetic BB/W rats replaced with C-peptide, no TdT-mediated dUTP nick-end labeling (TUNEL)-positive cells were shown and DNA laddering was not evident in hippocampus at either 2 or 8 months. C-peptide administration prevented the preceding perturbation of IGF expression and reduced the elevated ratio of Bax/Bcl-xL. Our data suggest that type 1 diabetes causes a duration-dependent programmed cell death of the hippocampus, which is partially prevented by C-peptide. 相似文献