620 research outputs found
Polymeric Separation Media: Binding of a§ unsaturated Carbonyl Compounds to Insoluble Resins through Michael Additions or Chelation of Derivatives
This is the publisher's version, also available electronically from "http://www.degruyter.com"
Bone marrow-derived endothelial progenitor cells are a major determinant of nascent tumor neovascularization
Tumors build vessels by cooption of pre-existing vasculature and de novo recruitment of bone marrow (BM)-derived endothelial progenitor cells (EPCs). However, the contribution and the functional role of EPCs in tumor neoangiogenesis are controversial. Therefore, by using genetically marked BM progenitor cells, we demonstrate the precise spatial and temporal contribution of EPCs to the neovascularization of three transplanted and one spontaneous breast tumor in vivo using high-resolution microscopy and flow cytometry. We show that early tumors recruit BM-derived EPCs that differentiate into mature BM-derived endothelial cells (ECs) and luminally incorporate into a subset of sprouting tumor neovessels. Notably, in later tumors, these BM-derived vessels are diluted with non-BM-derived vessels from the periphery, which accounts for purported differences in previously published reports. Furthermore, we show that specific ablation of BM-derived EPCs with alpha-particle-emitting anti-VE-cadherin antibody markedly impaired tumor growth associated with reduced vascularization. Our results demonstrate that BM-derived EPCs are critical components of the earliest phases of tumor neoangiogenesis
Expression profiling of metalloproteinases and tissue inhibitors of metalloproteinases in normal and degenerate human achilles tendon
To profile the messenger RNA (mRNA) expression for the 23 known genes of matrix metalloproteinases (MMPs), 19 genes of ADAMTS, 4 genes of tissue inhibitors of metalloproteinases (TIMPs), and ADAM genes 8, 10, 12, and 17 in normal, painful, and ruptured Achilles tendons. Tendon samples were obtained from cadavers or from patients undergoing surgical procedures to treat chronic painful tendinopathy or ruptured tendon. Total RNA was extracted and mRNA expression was analyzed by quantitative real-time reverse transcription–polymerase chain reaction, normalized to 18S ribosomal RNA. In comparing expression of all genes, the normal, painful, and ruptured Achilles tendon groups each had a distinct mRNA expression signature. Three mRNA were not detected and 14 showed no significant difference in expression levels between the groups. Statistically significant (P < 0.05) differences in mRNA expression, when adjusted for age, included lower levels of MMPs 3 and 10 and TIMP-3 and higher levels of ADAM-12 and MMP-23 in painful compared with normal tendons, and lower levels of MMPs 3 and 7 and TIMPs 2, 3, and 4 and higher levels of ADAMs 8 and 12, MMPs 1, 9, 19, and 25, and TIMP-1 in ruptured compared with normal tendons. The distinct mRNA profile of each tendon group suggests differences in extracellular proteolytic activity, which would affect the production and remodeling of the tendon extracellular matrix. Some proteolytic activities are implicated in the maintenance of normal tendon, while chronically painful tendons and ruptured tendons are shown to be distinct groups. These data will provide a foundation for further study of the role and activity of many of these enzymes that underlie the pathologic processes in the tendon
Nutrient adequacy during weight loss interventions: a randomized study in women comparing the dietary intake in a meal replacement group with a traditional food group
<p>Abstract</p> <p>Background</p> <p>Safe and effective weight control strategies are needed to stem the current obesity epidemic. The objective of this one-year study was to document and compare the macronutrient and micronutrient levels in the foods chosen by women following two different weight reduction interventions.</p> <p>Methods</p> <p>Ninety-six generally healthy overweight or obese women (ages 25–50 years; BMI 25–35 kg/m<sup>2</sup>) were randomized into a Traditional Food group (TFG) or a Meal Replacement Group (MRG) incorporating 1–2 meal replacement drinks or bars per day. Both groups had an energy-restricted goal of 5400 kJ/day. Dietary intake data was obtained using 3-Day Food records kept by the subjects at baseline, 6 months and one-year. For more uniform comparisons between groups, each diet intervention consisted of 18 small group sessions led by the same Registered Dietitian.</p> <p>Results</p> <p>Weight loss for the 73% (n = 70) completing this one-year study was not significantly different between the groups, but was significantly different (p ≤ .05) within each group with a mean (± standard deviation) weight loss of -6.1 ± 6.7 kg (TFG, n = 35) vs -5.0 ± 4.9 kg (MRG, n = 35). Both groups had macronutrient (Carbohydrate:Protein:Fat) ratios that were within the ranges recommended (50:19:31, TFG vs 55:16:29, MRG). Their reported reduced energy intake was similar (5729 ± 1424 kJ, TFG vs 5993 ± 2016 kJ, MRG). There was an improved dietary intake pattern in both groups as indicated by decreased intake of saturated fat (≤ 10%), cholesterol (<200 mg/day), and sodium (< 2400 mg/day), with increased total servings/day of fruits and vegetables (4.0 ± 2.2, TFG vs 4.6 ± 3.2, MRG). However, the TFG had a significantly lower dietary intake of several vitamins and minerals compared to the MRG and was at greater risk for inadequate intake.</p> <p>Conclusion</p> <p>In this one-year university-based intervention, both dietitian-led groups successfully lost weight while improving overall dietary adequacy. The group incorporating fortified meal replacements tended to have a more adequate essential nutrient intake compared to the group following a more traditional food group diet. This study supports the need to incorporate fortified foods and/or dietary supplements while following an energy-restricted diet for weight loss.</p
Setting the agenda for social science research on the human microbiome
The human microbiome is an important emergent area of cross, multi and transdisciplinary study. The complexity of this topic leads to conflicting narratives and regulatory challenges. It raises questions about the benefits of its commercialisation and drives debates about alternative models for engaging with its publics, patients and other potential beneficiaries. The social sciences and the humanities have begun to explore the microbiome as an object of empirical study and as an opportunity for theoretical innovation. They can play an important role in facilitating the development of research that is socially relevant, that incorporates cultural norms and expectations around microbes and that investigates how social and biological lives intersect. This is a propitious moment to establish lines of collaboration in the study of the microbiome that incorporate the concerns and capabilities of the social sciences and the humanities together with those of the natural sciences and relevant stakeholders outside academia. This paper presents an agenda for the engagement of the social sciences with microbiome research and its implications for public policy and social change. Our methods were informed by existing multidisciplinary science-policy agenda-setting exercises. We recruited 36 academics and stakeholders and asked them to produce a list of important questions about the microbiome that were in need of further social science research. We refined this initial list into an agenda of 32 questions and organised them into eight themes that both complement and extend existing research trajectories. This agenda was further developed through a structured workshop where 21 of our participants refined the agenda and reflected on the challenges and the limitations of the exercise itself. The agenda identifies the need for research that addresses the implications of the human microbiome for human health, public health, public and private sector research and notions of self and identity. It also suggests new lines of research sensitive to the complexity and heterogeneity of human–microbiome relations, and how these intersect with questions of environmental governance, social and spatial inequality and public engagement with science
Id-1 stimulates cell proliferation through activation of EGFR in ovarian cancer cells
Increased EGFR (epidermal growth factor receptor) expression has been reported in many types of human cancer and its levels are positively associated with advanced cancers. Recently, upregulation of Id-1 (inhibitor of differentiation or DNA binding) protein was found in over 70% of ovarian cancer samples and correlated with poor survival of ovarian cancer patients. However, the molecular mechanisms responsible for the role of Id-1 in ovarian cancer are not clear. The aim of this study was to investigate the effect of Id-1 on ovarian cancer proliferation and its association with the EGFR pathway. To achieve this, we transfected an Id-1 expression vector into three ovarian cancer cell lines and examined cell proliferation rate by flow cytometry and bromodeoxyuridine staining. We found that ectopic Id-1 expression led to increased cell proliferation demonstrated by increased BrdU incorporation rate and S-phase fraction. The Id-1-induced cell growth was associated with upregulation of EGFR at both transcriptional and protein levels. In contrast, inactivation of Id-1 through transfection of an Id-1 antisense vector resulted in downregulation of EGFR. Our results indicate that increased Id-1 in ovarian cancer cells may promote cancer cell proliferation through upregulation of EGFR. Our findings also implicate that Id-1 may be a potential target for the development of novel strategies in the treatment of ovarian cancer. © 2004 Cancer Research UK.link_to_OA_fulltex
Id-1 and Id-2 are markers for metastasis and prognosis in oesophageal squamous cell carcinoma
Id protein family consists of four members namely Id-1 to Id-4. Different from other basic helix–loop–helix transcription factors, they lack the DNA binding domain. Id proteins have been shown to be dysregulated in many different cancer types and their prognostic value has also been demonstrated. Recently, Id-1 has been shown to be upregulated in oesophageal squamous cell carcinoma (ESCC). However, the prognostic implications of Id proteins in ESCC have not been reported. We examined the expression of the Id proteins in ESCC cell lines and clinical ESCC specimens and found that Id protein expressions were dysregulated in both the ESCC cell lines and specimens. By correlating the expression levels of Id proteins and the clinicopathological data of our patient cohort, we found that M1 stage tumours had significantly higher nuclear Id-1 expression (P=0.012) while high nuclear Id-1 expression could predict development of distant metastasis within 1 year of oesophagectomy (P=0.005). In addition, high levels of Id-2 expression in both cytoplasmic and nuclear regions predicted longer patient survival (P=0.041). Multivariate analysis showed that high-level expression of Id-2 in both cytoplasmic and nuclear regions and lower level of nuclear Id-1 expression were independent favourable predictors of survival in our ESCC patients. Our results suggest that Id-1 may promote distant metastasis in ESCC, and both Id-1 and Id-2 may be used for prognostication for ESCC patients
The Intracellular Localization of ID2 Expression Has a Predictive Value in Non Small Cell Lung Cancer
ID2 is a member of a subclass of transcription regulators belonging to the general bHLH (basic-helix-loophelix) family of transcription factors. In normal cells, ID2 is responsible for regulating the balance between proliferation and differentiation. More recent studies have demonstrated that ID2 is involved in tumor progression in several cancer types such as prostate or breast
Adsorption at cell surface and cellular uptake of silica nanoparticles with different surface chemical functionalizations: impact on cytotoxicity
International audienceSilica nanoparticles are particularly interesting for medical applications because of the high inertness and chemical stability of silica material. However, at the nanoscale their innocuousness must be carefully verified before clinical use. The aim of this study was to investigate the in vitro biological toxicity of silica nanoparticles depending on their surface chemical functionalization. To that purpose, three kinds of 50 nm fluorescent silica-based nanoparticles were synthesized: 1) sterically stabilized silica nanoparticles coated with neutral polyethylene glycol (PEG) molecules, 2) positively charged silica nanoparticles coated with amine groups and 3) negatively charged silica nanoparticles coated with carboxylic acid groups. RAW 264.7 murine macrophages were incubated for 20 hours with each kind of nanoparticles. Their cellular uptake and adsorption at the cell membrane were assessed by a fluorimetric assay and cellular responses were evaluated in terms of cytotoxicity, pro-inflammatory factor production and oxidative stress. Results showed that the highly positive charged nanoparticle, were the most adsorbed at cell surface and triggered more cytotoxicity than other nanoparticles types. To conclude, this study clearly demonstrated that silica nanoparticles surface functionalization represents a key parameter in their cellular uptake and biological toxicity
Gene expression profiling integrated into network modelling reveals heterogeneity in the mechanisms of BRCA1 tumorigenesis
Background: gene expression profiling has distinguished sporadic breast tumour classes with genetic and clinical differences. Less is known about the molecular classification of familial breast tumours, which are generally considered to be less heterogeneous. Here, we describe molecular signatures that define BRCA1 subclasses depending on the expression of the gene encoding for oestrogen receptor, ESR1. Methods: for this purpose, we have used the Oncochip v2, a cancer-related cDNA microarray to analyze 14 BRCA1-associated breast tumours. Results: signatures were found to be molecularly associated with different biological processes and transcriptional regulatory programs. The signature of ESR1-positive tumours was mainly linked to cell proliferation and regulated by ER, whereas the signature of ESR1-negative tumours was mainly linked to the immune response and possibly regulated by transcription factors of the REL/NFκB family. These signatures were then verified in an independent series of familial and sporadic breast tumours, which revealed a possible prognostic value for each subclass. Over-expression of immune response genes seems to be a common feature of ER-negative sporadic and familial breast cancer and may be associated with good prognosis. Interestingly, the ESR1-negative tumours were substratified into two groups presenting slight differences in the magnitude of the expression of immune response transcripts and REL/NFκB transcription factors, which could be dependent on the type of BRCA1 germline mutation. Conclusion: this study reveals the molecular complexity of BRCA1 breast tumours, which are found to display similarities to sporadic tumours, and suggests possible prognostic implications
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