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81.
Heterogeneous pattern of chromosomal breakpoints involving the MYC locus in multiple myeloma 总被引:2,自引:0,他引:2
Fabris S Storlazzi CT Baldini L Nobili L Lombardi L Maiolo AT Rocchi M Neri A 《Genes, chromosomes & cancer》2003,37(3):261-269
Chromosomal rearrangements of the MYC locus, which often involve the IG loci, are recurrent events in multiple myeloma (MM) and plasma cell leukemia (PCL). We used dual-color fluorescence in situ hybridization (FISH) to characterize the breakpoint locations of chromosomal translocations/rearrangements involving the MYC locus at 8q24 found in a panel of 14 MM cell lines and 70 primary tumors (66 MM and 4 PCL). MYC locus alterations were observed in 21 cases: MYC/IG (mainly IGH@) fusions in 11 cell lines and three patients (2 MM and 1 PCL), and extra signals and/or abnormal MYC localizations in seven patients (5 MM and 2 PCL). Fourteen of these cases were investigated by FISH analyses by use of a panel of BAC clones covering about 6 Mb encompassing the MYC locus. The breakpoints were localized in a region 100-250 kb centromeric to MYC in four cases, a region 500-800 kb telomeric to the gene in four cases, and regions > or = 2 Mb centromeric or telomeric to MYC in five cases. Two different breakpoints were detected in the KMS-18 cell line, whereas the insertion of a MYC allele was found in a complex t(16;22) chromosomal translocation in the RPMI8226 cell line. Our data document a relatively high dispersion of 8q24 breakpoints in MM. 相似文献
82.
Antigenic sites of coxsackie A9 virus inducing neutralizing monoclonal antibodies protective in mice 总被引:1,自引:0,他引:1
A panel of murine IgG monoclonal antibodies (MAbs) was produced against coxsackievirus A9 (CAV9). Fifty-nine MAbs reactive in ELISA with purified CAV9 were identified. Eighteen of them could efficiently inhibit infection by CAV9 but not coxsackieviruses B. Neutralization-resistant CAV9 variants to four different MAbs were isolated and tested for resistance to neutralization by other MAbs of the panel. Three groups of reactivity including 10, 7, and 1 MAbs were thus identified. Sequencing of neutralization-escape virus mutants showed that neutralization by one MAb group was affected by change of VP3 amino acids 62 or 69. For the second group of reactivity, mutations included amino acids 154 or 165 of VP2. The only MAb of the third group selected for a change at residue 70 of VP2. Protection studies in a newborn mouse model of myositis suggested that either epitopes in VP2 or in VP3 mediate protection from CAV9 infection in vivo. 相似文献
83.
The negative role exerted by cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) in the regulation of T-cell activity, as induced by T-cell receptor (TCR)/CD3 and CD28 costimulation, has been widely described. In the present work we investigated the role of CTLA-4 in the control of cell activation, as induced by costimulation of the adhesion molecule lymphocyte function-associated antigen-1 (LFA-1) in murine CD4+ T cells. Results show that CTLA-4 engagement inhibits interleukin-2 (IL-2) production, not only when induced by CD3/CD28 costimulation, but also when CD4+ T cells are costimulated by anti-CD3 and anti-LFA-1 monoclonal antibodies (mAbs). LFA-1 has been described to induce Ca2+ mobilization also in the absence of TCR engagement. Moreover, we found that CTLA-4 engagement negatively affects Ca2+ mobilization and NF-AT activation, as induced by LFA-1 engagement alone. PLCgamma1 phosphorylation was also dampened within minutes after CTLA-4 engagement. Altogether these data indicate that through the control of signals induced by different receptors, CTLA-4 could be a global attenuator of T-cell activation. 相似文献
84.
85.
Jernimo P. Martins Lucia C. Silva Matheus S. Nunes Gabriel Rübensam Jarbas R. Oliveira Rodrigo B. M. Silva Maria M. Campos 《Nutrients》2021,13(4)
Dry extracts from the Eurasian plants, Ajuga turkestanica, Eurycoma longifolia, and Urtica dioica have been used as anabolic supplements, despite the limited scientific data on these effects. To assess their actions on early sarcopenia signs, male and female castrated mice were supplemented with lyophilized extracts of the three plants, isolated or in association (named TLU), and submitted to resistance exercise. Ovariectomy (OVX) led to body weight increase and non-high-density cholesterol (HDL) cholesterol elevation, which had been restored by exercise plus U. dioica extract, or by exercise and TLU, respectively. Orchiectomy (ORX) caused skeletal muscle weight loss, accompanied by increased adiposity, being the latter parameter reduced by exercise plus E. longifolia or U. dioica extracts. General physical activity was improved by exercise plus herbal extracts in either OVX or ORX animals. Exercise combined with TLU improved resistance to fatigue in OVX animals, though A. turkestanica enhanced the grip strength in ORX mice. E. longifolia or TLU also reduced the ladder climbing time in ORX mice. Resistance exercise plus herbal extracts partly altered gastrocnemius fiber size frequencies in OVX or ORX mice. We provide novel data that tested ergogenic extracts, when combined with resistance exercise, improved early sarcopenia alterations in castrated male and female mice. 相似文献
86.
Zuzana Paduchov Barbora Katren
íkov Magdalna Vavkov Lucia Laubertov Zuzana Nagyov Iveta Garaiova Zdenka ura
kov Jana Trebatick 《Nutrients》2021,13(4)
In the DEPOXIN project, we have found that a high ratio of omega-6/omega-3 fatty acids (FA) is associated with worsening of depressive symptoms in children and adolescents with depressive disorder (DD) and that the 12-week omega-3 FA supplementation modulates DD symptoms. Here we present our results of the secondary outcomes: the levels of thromboxane (TXB), brain-derived neurotrophic factor (BDNF), homocysteine (HCy) and vitamin D. Fifty-eight patients were randomized into two arms. One group received a fish oil emulsion enriched with omega-3 FA, and the other received a sunflower oil emulsion containing omega-6 FA, for 12 weeks. Depressive symptoms were evaluated, using the Child’s Depressive Inventory (CDI). The patients with DD had elevated TXB levels and decreased vitamin D levels, as compared to healthy controls. Both CDI and omega-6/omega-3 ratio correlated positively with TXB and negatively with BDNF at baseline. Compared to the omega-6 FA group, the supplementation with omega-3 FA for 12 weeks significantly reduced plasma TXB (p = 0.024) and increased BDNF (p = 0.011) levels. No changes in HCy and vitamin D were observed. Our results demonstrate the possible role of TXB and BDNF in the pathophysiology of DD and the benefits of omega-3 FA supplementation. The study was registered with the ISRCTN registry (ISRCTN81655012). 相似文献
87.
Dan Liu Maria Lucia Pace Maria Goddard Rowena Jacobs Raphael Wittenberg Anne Mason 《Health economics》2021,30(1):36-54
Since 2010, adult social care spending in England has fallen significantly in real terms whilst demand has risen. Reductions in social care supply may also have impacted demand for NHS services, particularly for those whose care is provided at the interface of the health and care systems. We analyzed a panel dataset of 150 local authorities (councils) to test potential impacts on hospital utilization by people aged 65 and over: emergency admission rates for falls and hip fractures (“front‐door” measures); and extended stays of 7 days or longer; and 21 days or longer (“back‐door” measures). Changes in social care supply were assessed in two ways: gross current expenditure (per capita 65 and over) adjusted by local labor costs and social care workforce (per capita 18 and over). We ran negative binomial models, controlling for deprivation, ethnicity, age, unpaid care, council class, and year effects. To account for potential endogeneity, we ran instrumental variable regressions and dynamic panel models. Sensitivity analysis explored potential effects of funding for integrated care (the Better Care Fund). There was no consistent evidence that councils with higher per capita spend or higher social care staffing rates had lower hospital admission rates or shorter hospital stays. 相似文献
88.
89.
Leticia Faria Serpa Margarita Maria Ortiz Anne Chaves Lima Línea Bueno Paula Cristina Nogueira Cleusa Ferri Vera Lucia Conceio De Gouveia Santos 《Wound repair and regeneration》2021,29(1):79-86
This study aimed to estimate the incidence of hospital‐acquired pressure injury (PI) and its risk factors in inpatient and intensive care units of five hospitals (two public and three private) in the city of Sao Paulo, Brazil. A 6‐month follow‐up prospective cohort study (n = 1937) was conducted from April to September 2013. Baseline and follow‐up measurements included demographic and care information, as well as risk assessments for both undernutrition (NRS‐2002) and PI (Braden scale). Poisson regression with robust variance was used for data analysis. A total of 633 patients (32.60%) showed risk for PI. The incidence rate of PI was of 5.9% (9.9% in public hospitals vs 4.1% in private hospitals) and was higher in intensive care units, compared to inpatient care units (10% vs 5.7%, respectively). Risk for PI increased with age (RR = 1.05; 95% CI 1.04‐1.07); was higher in in public hospitals, compared to private hospitals (RR = 4.39; 95% CI 2.92‐6.61); in patients admitted for non‐surgical reasons compared to those admitted for surgical reasons (RR = 1.91; 95% CI 1.12‐3.27); in patients with longer hospital stays (RR = 1.04; 95% CI 1.03‐1.06); high blood pressure (RR = 1.76; 95% CI 1.17‐2.64); or had a risk for undernutrition (RR = 3.51; 95% CI 1.71‐7.24). Higher scores in the Braden scale was associated with a decreased risk of PI (RR = 0.79; 95% CI 0.75‐0.83). The results of our study indicate that 5.9% of all patients developed PI and that the most important factors that nurses should consider are: patient age, care setting, length of hospitalization, comorbidities, reason for admission and nutrition when planning and implementing PI‐preventative actions. 相似文献
90.