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1.
Demography ; 60(1): 1-14, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36692169

RESUMO

State-level disparities in life expectancy are wide, persistent, and potentially growing in the United States. However, the extent to which differences in lifespan variability by state have changed over time is unclear. This research note describes trends in lifespan variability for the United States overall and by state from 1960 to 2019 using period life table data from the United States Mortality Database. Lifespan disparity at birth (e0†) decreased over time in the United States overall from 14.0 years in 1960-1964 to 12.2 in 2015-2019. Lifespan variability decreased in all states, but states differed in the level and pace with which these changes occurred. Southern states and the District of Columbia exhibited consistently higher (i.e., less equitable) levels of lifespan variability than the nation overall. Conversely, lifespan variability was lower among several states in the Northeast (e.g., Connecticut and Massachusetts), Upper Midwest (e.g., Iowa, Minnesota, and Wisconsin), and West (e.g., California, Oregon, Utah, and Washington). We observe a particularly worrisome trend of increasing lifespan variability for the United States overall and for most states from 2010-2014 to 2015-2019. Monitoring state-level trends in lifespan variability has the potential to inform policies designed to ameliorate population health disparities.


Assuntos
Longevidade , Recém-Nascido , Estados Unidos , Humanos , Massachusetts , Utah , Wisconsin
2.
J Magn Reson Imaging ; 53(5): 1410-1421, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33594733

RESUMO

BACKGROUND: Non-invasive assessment of the hemodynamic changes of cirrhosis might help guide management of patients with liver disease but are currently limited. PURPOSE: To determine whether free-breathing 4D flow MRI can be used to quantify the hemodynamic effects of cirrhosis and introduce hydraulic circuit indexes of severity. STUDY TYPE: Retrospective. POPULATION: Forty-seven patients including 26 with cirrhosis. FIELD STRENGTH/SEQUENCE: 3 T/free-breathing 4D flow MRI with soft gating and golden-angle view ordering. ASSESSMENT: Measurements of the supra-celiac abdominal aorta, supra-renal abdominal aorta (SRA), celiac trunk (CeT), superior mesenteric artery (SMA), splenic artery (SpA), common hepatic artery (CHA), portal vein (PV), and supra-renal inferior vena cava (IVC) were made by two radiologists. Measures of hepatic vascular resistance (hepatic arterial relative resistance [HARR]; portal resistive index [PRI]) were proposed and calculated. STATISTICAL ANALYSIS: Bland-Altman, Pearson's correlation, Tukey's multiple comparison, and Cohen's kappa. P < 0.05 was considered significant. RESULTS: Forty-four of 47 studies yielded adequate image quality for flow quantification (94%). Arterial structures showed high inter-reader concordance (range; ρ = 0.948-0.987) and the IVC (ρ = 0.972), with moderate concordance in the PV (ρ = 0.866). Conservation of mass analysis showed concordance between large vessels (SRA vs. IVC; ρ = 0.806), small vessels (celiac vs. CHA + SpA; ρ = 0.939), and across capillary beds (CeT + SMA vs. PV; ρ = 0.862). Splanchnic flow was increased in patients with portosystemic shunting (PSS) relative to control patients and patients with cirrhosis without PSS (P < 0.05, difference range 0.11-0.68 liter/m). HARR was elevated and PRI was decreased in patients with PSS (3.55 and 1.49, respectively) compared to both the control (2.11/3.18) and non-PSS (2.11/2.35) cohorts. DATA CONCLUSION: 4D flow MRI with self-navigation was technically feasible, showing promise in quantifying the hemodynamic effects of cirrhosis. Proposed quantitative metrics of hepatic vascular resistance correlated with PSS. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY STAGE: 2.


Assuntos
Hemodinâmica , Cirrose Hepática , Velocidade do Fluxo Sanguíneo , Humanos , Cirrose Hepática/diagnóstico por imagem , Imageamento por Ressonância Magnética , Veia Porta , Estudos Retrospectivos
3.
J Bacteriol ; 202(8)2020 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-31792010

RESUMO

Cystic fibrosis (CF) patients chronically infected with both Pseudomonas aeruginosa and Staphylococcus aureus have worse health outcomes than patients who are monoinfected with either P. aeruginosa or S. aureus We showed previously that mucoid strains of P. aeruginosa can coexist with S. aureusin vitro due to the transcriptional downregulation of several toxic exoproducts typically produced by P. aeruginosa, including siderophores, rhamnolipids, and HQNO (2-heptyl-4-hydroxyquinoline N-oxide). Here, we demonstrate that exogenous alginate protects S. aureus from P. aeruginosa in both planktonic and biofilm coculture models under a variety of nutritional conditions. S. aureus protection in the presence of exogenous alginate is due to the transcriptional downregulation of pvdA, a gene required for the production of the iron-scavenging siderophore pyoverdine as well as the downregulation of the PQS (Pseudomonas quinolone signal) (2-heptyl-3,4-dihydroxyquinoline) quorum sensing system. The impact of exogenous alginate is independent of endogenous alginate production. We further demonstrate that coculture of mucoid P. aeruginosa with nonmucoid P. aeruginosa strains can mitigate the killing of S. aureus by the nonmucoid strain of P. aeruginosa, indicating that the mechanism that we describe here may function in vivo in the context of mixed infections. Finally, we investigated a panel of mucoid clinical isolates that retain the ability to kill S. aureus at late time points and show that each strain has a unique expression profile, indicating that mucoid isolates can overcome the S. aureus-protective effects of mucoidy in a strain-specific manner.IMPORTANCE CF patients are chronically infected by polymicrobial communities. The two dominant bacterial pathogens that infect the lungs of CF patients are P. aeruginosa and S. aureus, with ∼30% of patients coinfected by both species. Such coinfected individuals have worse outcomes than monoinfected patients, and both species persist within the same physical space. A variety of host and environmental factors have been demonstrated to promote P. aeruginosa-S. aureus coexistence, despite evidence that P. aeruginosa kills S. aureus when these organisms are cocultured in vitro Thus, a better understanding of P. aeruginosa-S. aureus interactions, particularly mechanisms by which these microorganisms are able to coexist in proximal physical space, will lead to better-informed treatments for chronic polymicrobial infections.


Assuntos
Alginatos/metabolismo , Fibrose Cística/microbiologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/fisiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/metabolismo , Biofilmes , Coinfecção/microbiologia , Humanos , Interações Microbianas , Pseudomonas aeruginosa/genética , Staphylococcus aureus/genética
4.
Br J Nutr ; 117(9): 1244-1256, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28643618

RESUMO

Rice bran (RB) consumption has been shown to reduce colorectal cancer (CRC) growth in mice and modify the human stool microbiome. Changes in host and microbial metabolism induced by RB consumption was hypothesised to modulate the stool metabolite profile in favour of promoting gut health and inhibiting CRC growth. The objective was to integrate gut microbial metabolite profiles and identify metabolic pathway networks for CRC chemoprevention using non-targeted metabolomics. In all, nineteen CRC survivors participated in a parallel randomised controlled dietary intervention trial that included daily consumption of study-provided foods with heat-stabilised RB (30 g/d) or no additional ingredient (control). Stool samples were collected at baseline and 4 weeks and analysed using GC-MS and ultra-performance liquid chromatography-MS. Stool metabolomics revealed 93 significantly different metabolites in individuals consuming RB. A 264-fold increase in ß-hydroxyisovaleroylcarnitine and 18-fold increase in ß-hydroxyisovalerate exemplified changes in leucine, isoleucine and valine metabolism in the RB group. A total of thirty-nine stool metabolites were significantly different between RB and control groups, including increased hesperidin (28-fold) and narirutin (14-fold). Metabolic pathways impacted in the RB group over time included advanced glycation end products, steroids and bile acids. Fatty acid, leucine/valine and vitamin B6 metabolic pathways were increased in RB compared with control. There were 453 metabolites identified in the RB food metabolome, thirty-nine of which were identified in stool from RB consumers. RB consumption favourably modulated the stool metabolome of CRC survivors and these findings suggest the need for continued dietary CRC chemoprevention efforts.


Assuntos
Neoplasias Colorretais , Fibras na Dieta/administração & dosagem , Fezes/química , Manipulação de Alimentos , Redes e Vias Metabólicas/efeitos dos fármacos , Oryza , Humanos
5.
Nutr Cancer ; 68(8): 1269-1280, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27689688

RESUMO

Consumption of navy beans (NB) and rice bran (RB) have been shown to inhibit colon carcinogenesis. Given the overall poor diet quality in colorectal cancer (CRC) survivors and low reported intake of whole grains and legumes, practical strategies to increase consumption merit attention. This study determined feasibility of increasing NB or RB intake in CRC survivors to increase dietary fiber and examined serum inflammatory biomarkers and telomere lengths. Twenty-nine subjects completed a randomized controlled trial with foods that included cooked NB powder (35 g/day), heat-stabilized RB (30 g/day), or no additional ingredient. Fasting blood, food logs, and gastrointestinal health questionnaires were collected. The amount of NB or RB consumed equated to 4-9% of subjects' daily caloric intake and no major gastrointestinal issues were reported with increased consumption. Dietary fiber amounts increased in NB and RB groups at Weeks 2 and 4 compared to baseline and to control (P ≤ 0.01). Telomere length correlated with age and HDL cholesterol at baseline, and with improved serum amyloid A (SAA) levels at Week 4 (P ≤ 0.05). This study concludes feasibility of increased dietary NB and RB consumption to levels associated with CRC chemoprevention and warrants longer-term investigations with both foods in high-risk populations that include cancer prevention and control outcomes.


Assuntos
Fibras na Dieta/farmacologia , Inflamação/dietoterapia , Oryza , Phaseolus , Idoso , Biomarcadores/sangue , Sobreviventes de Câncer , HDL-Colesterol/sangue , Neoplasias Colorretais/complicações , Suplementos Nutricionais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteína Amiloide A Sérica/análise , Homeostase do Telômero
6.
Carcinogenesis ; 36 Suppl 1: S19-37, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26106138

RESUMO

Carcinogenesis is thought to be a multistep process, with clonal evolution playing a central role in the process. Clonal evolution involves the repeated 'selection and succession' of rare variant cells that acquire a growth advantage over the remaining cell population through the acquisition of 'driver mutations' enabling a selective advantage in a particular micro-environment. Clonal selection is the driving force behind tumorigenesis and possesses three basic requirements: (i) effective competitive proliferation of the variant clone when compared with its neighboring cells, (ii) acquisition of an indefinite capacity for self-renewal, and (iii) establishment of sufficiently high levels of genetic and epigenetic variability to permit the emergence of rare variants. However, several questions regarding the process of clonal evolution remain. Which cellular processes initiate carcinogenesis in the first place? To what extent are environmental carcinogens responsible for the initiation of clonal evolution? What are the roles of genotoxic and non-genotoxic carcinogens in carcinogenesis? What are the underlying mechanisms responsible for chemical carcinogen-induced cellular immortality? Here, we explore the possible mechanisms of cellular immortalization, the contribution of immortalization to tumorigenesis and the mechanisms by which chemical carcinogens may contribute to these processes.


Assuntos
Carcinogênese/induzido quimicamente , Carcinógenos/administração & dosagem , Senescência Celular/efeitos dos fármacos , Substâncias Perigosas/efeitos adversos , Animais , Exposição Ambiental/efeitos adversos , Humanos
7.
Carcinogenesis ; 36 Suppl 1: S203-31, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26106140

RESUMO

Environmental contributions to cancer development are widely accepted, but only a fraction of all pertinent exposures have probably been identified. Traditional toxicological approaches to the problem have largely focused on the effects of individual agents at singular endpoints. As such, they have incompletely addressed both the pro-carcinogenic contributions of environmentally relevant low-dose chemical mixtures and the fact that exposures can influence multiple cancer-associated endpoints over varying timescales. Of these endpoints, dysregulated metabolism is one of the most common and recognizable features of cancer, but its specific roles in exposure-associated cancer development remain poorly understood. Most studies have focused on discrete aspects of cancer metabolism and have incompletely considered both its dynamic integrated nature and the complex controlling influences of substrate availability, external trophic signals and environmental conditions. Emerging high throughput approaches to environmental risk assessment also do not directly address the metabolic causes or consequences of changes in gene expression. As such, there is a compelling need to establish common or complementary frameworks for further exploration that experimentally and conceptually consider the gestalt of cancer metabolism and its causal relationships to both carcinogenesis and the development of other cancer hallmarks. A literature review to identify environmentally relevant exposures unambiguously linked to both cancer development and dysregulated metabolism suggests major gaps in our understanding of exposure-associated carcinogenesis and metabolic reprogramming. Although limited evidence exists to support primary causal roles for metabolism in carcinogenesis, the universality of altered cancer metabolism underscores its fundamental biological importance, and multiple pleiomorphic, even dichotomous, roles for metabolism in promoting, antagonizing or otherwise enabling the development and selection of cancer are suggested.


Assuntos
Carcinogênese/induzido quimicamente , Carcinogênese/metabolismo , Carcinógenos Ambientais/efeitos adversos , Exposição Ambiental/efeitos adversos , Neoplasias/induzido quimicamente , Neoplasias/metabolismo , Animais , Humanos , Neoplasias/etiologia
8.
Carcinogenesis ; 36 Suppl 1: S232-53, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26106141

RESUMO

An emerging area in environmental toxicology is the role that chemicals and chemical mixtures have on the cells of the human immune system. This is an important area of research that has been most widely pursued in relation to autoimmune diseases and allergy/asthma as opposed to cancer causation. This is despite the well-recognized role that innate and adaptive immunity play as essential factors in tumorigenesis. Here, we review the role that the innate immune cells of inflammatory responses play in tumorigenesis. Focus is placed on the molecules and pathways that have been mechanistically linked with tumor-associated inflammation. Within the context of chemically induced disturbances in immune function as co-factors in carcinogenesis, the evidence linking environmental toxicant exposures with perturbation in the balance between pro- and anti-inflammatory responses is reviewed. Reported effects of bisphenol A, atrazine, phthalates and other common toxicants on molecular and cellular targets involved in tumor-associated inflammation (e.g. cyclooxygenase/prostaglandin E2, nuclear factor kappa B, nitric oxide synthesis, cytokines and chemokines) are presented as example chemically mediated target molecule perturbations relevant to cancer. Commentary on areas of additional research including the need for innovation and integration of systems biology approaches to the study of environmental exposures and cancer causation are presented.


Assuntos
Carcinógenos Ambientais/efeitos adversos , Exposição Ambiental/efeitos adversos , Inflamação/induzido quimicamente , Inflamação/imunologia , Neoplasias/induzido quimicamente , Neoplasias/imunologia , Animais , Carcinogênese/induzido quimicamente , Carcinogênese/imunologia , Humanos , Imunidade Inata/efeitos dos fármacos , Imunidade Inata/imunologia , Neoplasias/etiologia , Risco
9.
Carcinogenesis ; 36 Suppl 1: S111-27, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26002081

RESUMO

An increasing number of studies suggest an important role of host immunity as a barrier to tumor formation and progression. Complex mechanisms and multiple pathways are involved in evading innate and adaptive immune responses, with a broad spectrum of chemicals displaying the potential to adversely influence immunosurveillance. The evaluation of the cumulative effects of low-dose exposures from the occupational and natural environment, especially if multiple chemicals target the same gene(s) or pathway(s), is a challenge. We reviewed common environmental chemicals and discussed their potential effects on immunosurveillance. Our overarching objective was to review related signaling pathways influencing immune surveillance such as the pathways involving PI3K/Akt, chemokines, TGF-ß, FAK, IGF-1, HIF-1α, IL-6, IL-1α, CTLA-4 and PD-1/PDL-1 could individually or collectively impact immunosurveillance. A number of chemicals that are common in the anthropogenic environment such as fungicides (maneb, fluoxastrobin and pyroclostrobin), herbicides (atrazine), insecticides (pyridaben and azamethiphos), the components of personal care products (triclosan and bisphenol A) and diethylhexylphthalate with pathways critical to tumor immunosurveillance. At this time, these chemicals are not recognized as human carcinogens; however, it is known that they these chemicalscan simultaneously persist in the environment and appear to have some potential interfere with the host immune response, therefore potentially contributing to promotion interacting with of immune evasion mechanisms, and promoting subsequent tumor growth and progression.


Assuntos
Substâncias Perigosas/efeitos adversos , Substâncias Perigosas/imunologia , Evasão da Resposta Imune/efeitos dos fármacos , Vigilância Imunológica/efeitos dos fármacos , Neoplasias/induzido quimicamente , Neoplasias/imunologia , Animais , Meio Ambiente , Humanos , Evasão da Resposta Imune/imunologia , Vigilância Imunológica/imunologia , Neoplasias/etiologia
10.
Carcinogenesis ; 36 Suppl 1: S160-83, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26106136

RESUMO

Potentially carcinogenic compounds may cause cancer through direct DNA damage or through indirect cellular or physiological effects. To study possible carcinogens, the fields of endocrinology, genetics, epigenetics, medicine, environmental health, toxicology, pharmacology and oncology must be considered. Disruptive chemicals may also contribute to multiple stages of tumor development through effects on the tumor microenvironment. In turn, the tumor microenvironment consists of a complex interaction among blood vessels that feed the tumor, the extracellular matrix that provides structural and biochemical support, signaling molecules that send messages and soluble factors such as cytokines. The tumor microenvironment also consists of many host cellular effectors including multipotent stromal cells/mesenchymal stem cells, fibroblasts, endothelial cell precursors, antigen-presenting cells, lymphocytes and innate immune cells. Carcinogens can influence the tumor microenvironment through effects on epithelial cells, the most common origin of cancer, as well as on stromal cells, extracellular matrix components and immune cells. Here, we review how environmental exposures can perturb the tumor microenvironment. We suggest a role for disrupting chemicals such as nickel chloride, Bisphenol A, butyltins, methylmercury and paraquat as well as more traditional carcinogens, such as radiation, and pharmaceuticals, such as diabetes medications, in the disruption of the tumor microenvironment. Further studies interrogating the role of chemicals and their mixtures in dose-dependent effects on the tumor microenvironment could have important general mechanistic implications for the etiology and prevention of tumorigenesis.


Assuntos
Exposição Ambiental/efeitos adversos , Substâncias Perigosas/efeitos adversos , Microambiente Tumoral/efeitos dos fármacos , Animais , Carcinogênese/induzido quimicamente , Humanos , Neoplasias/induzido quimicamente
11.
Carcinogenesis ; 36 Suppl 1: S2-18, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26106139

RESUMO

As part of the Halifax Project, this review brings attention to the potential effects of environmental chemicals on important molecular and cellular regulators of the cancer hallmark of evading growth suppression. Specifically, we review the mechanisms by which cancer cells escape the growth-inhibitory signals of p53, retinoblastoma protein, transforming growth factor-beta, gap junctions and contact inhibition. We discuss the effects of selected environmental chemicals on these mechanisms of growth inhibition and cross-reference the effects of these chemicals in other classical cancer hallmarks.


Assuntos
Exposição Ambiental/efeitos adversos , Substâncias Perigosas/efeitos adversos , Neoplasias/induzido quimicamente , Neoplasias/etiologia , Animais , Humanos , Transdução de Sinais/efeitos dos fármacos
12.
Carcinogenesis ; 36 Suppl 1: S184-202, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26106137

RESUMO

One of the important 'hallmarks' of cancer is angiogenesis, which is the process of formation of new blood vessels that are necessary for tumor expansion, invasion and metastasis. Under normal physiological conditions, angiogenesis is well balanced and controlled by endogenous proangiogenic factors and antiangiogenic factors. However, factors produced by cancer cells, cancer stem cells and other cell types in the tumor stroma can disrupt the balance so that the tumor microenvironment favors tumor angiogenesis. These factors include vascular endothelial growth factor, endothelial tissue factor and other membrane bound receptors that mediate multiple intracellular signaling pathways that contribute to tumor angiogenesis. Though environmental exposures to certain chemicals have been found to initiate and promote tumor development, the role of these exposures (particularly to low doses of multiple substances), is largely unknown in relation to tumor angiogenesis. This review summarizes the evidence of the role of environmental chemical bioactivity and exposure in tumor angiogenesis and carcinogenesis. We identify a number of ubiquitous (prototypical) chemicals with disruptive potential that may warrant further investigation given their selectivity for high-throughput screening assay targets associated with proangiogenic pathways. We also consider the cross-hallmark relationships of a number of important angiogenic pathway targets with other cancer hallmarks and we make recommendations for future research. Understanding of the role of low-dose exposure of chemicals with disruptive potential could help us refine our approach to cancer risk assessment, and may ultimately aid in preventing cancer by reducing or eliminating exposures to synergistic mixtures of chemicals with carcinogenic potential.


Assuntos
Carcinogênese/induzido quimicamente , Carcinógenos Ambientais/efeitos adversos , Exposição Ambiental/efeitos adversos , Substâncias Perigosas/efeitos adversos , Neoplasias/induzido quimicamente , Neoplasias/etiologia , Neovascularização Patológica/induzido quimicamente , Animais , Humanos
13.
Carcinogenesis ; 36 Suppl 1: S128-59, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26106135

RESUMO

The purpose of this review is to stimulate new ideas regarding low-dose environmental mixtures and carcinogens and their potential to promote invasion and metastasis. Whereas a number of chapters in this review are devoted to the role of low-dose environmental mixtures and carcinogens in the promotion of invasion and metastasis in specific tumors such as breast and prostate, the overarching theme is the role of low-dose carcinogens in the progression of cancer stem cells. It is becoming clearer that cancer stem cells in a tumor are the ones that assume invasive properties and colonize distant organs. Therefore, low-dose contaminants that trigger epithelial-mesenchymal transition, for example, in these cells are of particular interest in this review. This we hope will lead to the collaboration between scientists who have dedicated their professional life to the study of carcinogens and those whose interests are exclusively in the arena of tissue invasion and metastasis.


Assuntos
Carcinógenos Ambientais/efeitos adversos , Invasividade Neoplásica/patologia , Metástase Neoplásica/patologia , Animais , Progressão da Doença , Exposição Ambiental/efeitos adversos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos
14.
Carcinogenesis ; 36 Suppl 1: S38-60, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26106143

RESUMO

The aim of this work is to review current knowledge relating the established cancer hallmark, sustained cell proliferation to the existence of chemicals present as low dose mixtures in the environment. Normal cell proliferation is under tight control, i.e. cells respond to a signal to proliferate, and although most cells continue to proliferate into adult life, the multiplication ceases once the stimulatory signal disappears or if the cells are exposed to growth inhibitory signals. Under such circumstances, normal cells remain quiescent until they are stimulated to resume further proliferation. In contrast, tumour cells are unable to halt proliferation, either when subjected to growth inhibitory signals or in the absence of growth stimulatory signals. Environmental chemicals with carcinogenic potential may cause sustained cell proliferation by interfering with some cell proliferation control mechanisms committing cells to an indefinite proliferative span.


Assuntos
Carcinógenos Ambientais/efeitos adversos , Proliferação de Células/efeitos dos fármacos , Exposição Ambiental/efeitos adversos , Substâncias Perigosas/efeitos adversos , Neoplasias/induzido quimicamente , Neoplasias/etiologia , Transdução de Sinais/efeitos dos fármacos , Animais , Humanos
15.
Carcinogenesis ; 36 Suppl 1: S61-88, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26106144

RESUMO

Genome instability is a prerequisite for the development of cancer. It occurs when genome maintenance systems fail to safeguard the genome's integrity, whether as a consequence of inherited defects or induced via exposure to environmental agents (chemicals, biological agents and radiation). Thus, genome instability can be defined as an enhanced tendency for the genome to acquire mutations; ranging from changes to the nucleotide sequence to chromosomal gain, rearrangements or loss. This review raises the hypothesis that in addition to known human carcinogens, exposure to low dose of other chemicals present in our modern society could contribute to carcinogenesis by indirectly affecting genome stability. The selected chemicals with their mechanisms of action proposed to indirectly contribute to genome instability are: heavy metals (DNA repair, epigenetic modification, DNA damage signaling, telomere length), acrylamide (DNA repair, chromosome segregation), bisphenol A (epigenetic modification, DNA damage signaling, mitochondrial function, chromosome segregation), benomyl (chromosome segregation), quinones (epigenetic modification) and nano-sized particles (epigenetic pathways, mitochondrial function, chromosome segregation, telomere length). The purpose of this review is to describe the crucial aspects of genome instability, to outline the ways in which environmental chemicals can affect this cancer hallmark and to identify candidate chemicals for further study. The overall aim is to make scientists aware of the increasing need to unravel the underlying mechanisms via which chemicals at low doses can induce genome instability and thus promote carcinogenesis.


Assuntos
Carcinogênese/induzido quimicamente , Carcinógenos Ambientais/efeitos adversos , Exposição Ambiental/efeitos adversos , Instabilidade Genômica/efeitos dos fármacos , Substâncias Perigosas/efeitos adversos , Neoplasias/induzido quimicamente , Neoplasias/etiologia , Animais , Humanos
16.
Carcinogenesis ; 36 Suppl 1: S89-110, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26106145

RESUMO

Cell death is a process of dying within biological cells that are ceasing to function. This process is essential in regulating organism development, tissue homeostasis, and to eliminate cells in the body that are irreparably damaged. In general, dysfunction in normal cellular death is tightly linked to cancer progression. Specifically, the up-regulation of pro-survival factors, including oncogenic factors and antiapoptotic signaling pathways, and the down-regulation of pro-apoptotic factors, including tumor suppressive factors, confers resistance to cell death in tumor cells, which supports the emergence of a fully immortalized cellular phenotype. This review considers the potential relevance of ubiquitous environmental chemical exposures that have been shown to disrupt key pathways and mechanisms associated with this sort of dysfunction. Specifically, bisphenol A, chlorothalonil, dibutyl phthalate, dichlorvos, lindane, linuron, methoxychlor and oxyfluorfen are discussed as prototypical chemical disruptors; as their effects relate to resistance to cell death, as constituents within environmental mixtures and as potential contributors to environmental carcinogenesis.


Assuntos
Carcinogênese/induzido quimicamente , Carcinógenos Ambientais/efeitos adversos , Morte Celular/efeitos dos fármacos , Exposição Ambiental/efeitos adversos , Substâncias Perigosas/efeitos adversos , Neoplasias/induzido quimicamente , Neoplasias/etiologia , Animais , Homeostase/efeitos dos fármacos , Humanos
17.
Carcinogenesis ; 36 Suppl 1: S254-96, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26106142

RESUMO

Lifestyle factors are responsible for a considerable portion of cancer incidence worldwide, but credible estimates from the World Health Organization and the International Agency for Research on Cancer (IARC) suggest that the fraction of cancers attributable to toxic environmental exposures is between 7% and 19%. To explore the hypothesis that low-dose exposures to mixtures of chemicals in the environment may be combining to contribute to environmental carcinogenesis, we reviewed 11 hallmark phenotypes of cancer, multiple priority target sites for disruption in each area and prototypical chemical disruptors for all targets, this included dose-response characterizations, evidence of low-dose effects and cross-hallmark effects for all targets and chemicals. In total, 85 examples of chemicals were reviewed for actions on key pathways/mechanisms related to carcinogenesis. Only 15% (13/85) were found to have evidence of a dose-response threshold, whereas 59% (50/85) exerted low-dose effects. No dose-response information was found for the remaining 26% (22/85). Our analysis suggests that the cumulative effects of individual (non-carcinogenic) chemicals acting on different pathways, and a variety of related systems, organs, tissues and cells could plausibly conspire to produce carcinogenic synergies. Additional basic research on carcinogenesis and research focused on low-dose effects of chemical mixtures needs to be rigorously pursued before the merits of this hypothesis can be further advanced. However, the structure of the World Health Organization International Programme on Chemical Safety 'Mode of Action' framework should be revisited as it has inherent weaknesses that are not fully aligned with our current understanding of cancer biology.


Assuntos
Carcinogênese/induzido quimicamente , Carcinógenos Ambientais/efeitos adversos , Exposição Ambiental/efeitos adversos , Substâncias Perigosas/efeitos adversos , Neoplasias/induzido quimicamente , Neoplasias/etiologia , Animais , Humanos
18.
Environ Sci Technol ; 48(24): 14677-85, 2014 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-25365583

RESUMO

The objective of this study was to determine the background exposures to pesticides as detected in urine from 21 healthy companion dogs in Northern Colorado. A panel of 301 pesticides was used to screen urine samples collected from dogs using an established ultraperformance liquid chromatography-mass spectrometry (UPLC-MS/MS) platform. Canine food intakes were controlled for one month on diets that were also screened for pesticide contents. Fifteen distinct pesticides were detected in urine. The most frequently detected compounds in canine urine samples collected over a 1 month period were atrazine, fuberidazole, imidacloprid, terbumeton, and clopyralid. Fuberidazole was the only pesticide detected in both the diets and urine. Companion dogs develop many similar chronic diseases as humans and represent a relevant model for biomonitoring combinations of environmental pesticide exposures, as well as for evaluating the potential relationships between environmental exposures and disease risk.


Assuntos
Exposição Ambiental/análise , Praguicidas/urina , Animais , Atrazina/urina , Benzimidazóis/análise , Benzimidazóis/urina , Cromatografia Líquida/métodos , Colorado , Cães , Ingestão de Alimentos , Monitoramento Ambiental/métodos , Feminino , Masculino , Espectrometria de Massas , Praguicidas/análise , Animais de Estimação/urina , Espectrometria de Massas em Tandem/métodos
19.
J Cross Cult Gerontol ; 29(3): 243-58, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24909895

RESUMO

Much like other racial/ethnic groups, Latinos are facing challenges to provide needed care to aging adults. Older Latinos underutilize nursing homes and home health care services and primarily rely on their families for assistance. While this general trend has been established, little attention has been paid to nativity differentials in patterns of caregiving for this segment of the aging population. The analyses are based on the latest wave (Wave 7) of the Hispanic Established Population for Epidemiologic Studies of the Elderly or H-EPESE (2010/2011) a sample of older Mexican-origin adults and their family caregivers living in the southwestern U.S. We examine 629 child caregiver/parent care recipient dyads using bivariate statistics and multinomial logistic regression analyses. The results reveal that while grown children of Mexican-origin elders play a critical role in providing instrumental and financial supports to their aging parents, the burden that the children of foreign-born parents bear is greater. Despite higher rates of disability, Mexican-born elders are more dependent on a child for help and far less likely to call upon other family members, relatives and community based-providers for help than the U.S. born. Given the recent and future growth of older Latinos, intervention strategies will need to focus on nativity status and acculturative processes in the context of caregiving and caregiver burden.


Assuntos
Cuidadores/estatística & dados numéricos , Necessidades e Demandas de Serviços de Saúde/estatística & dados numéricos , Serviços de Assistência Domiciliar/estatística & dados numéricos , Americanos Mexicanos/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Estudos de Coortes , Etnicidade , Família , Feminino , Idoso Fragilizado , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Pais , Estados Unidos
20.
J Dev Behav Pediatr ; 44(2): e88-e94, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36729525

RESUMO

OBJECTIVE: The COVID-19 pandemic has exacerbated differences related to employment and family psychological health. However, empirical evidence examining COVID-19-linked differences concerning children and families remains scant. This study addresses this gap by examining sociodemographic differences associated with COVID-19 on family access to resources and family psychological health. METHOD: A telephone survey of 600 caregivers living in Mississippi was conducted from August 2020 to April 2021. Caregivers answered questions about levels of worry regarding themselves or their child contracting COVID-19 and impact of the pandemic on household income, access to resources, and family psychological health. RESULTS: Multivariate models demonstrated that Black caregivers (n = 273; 45.5%) had increased odds of agreeing that they worry about contracting COVID-19 (odds ratio [OR] = 2.57). Furthermore, as caregiver reported household annual income decreased, caregivers had increased odds of agreeing that they worry about contracting COVID-19 (OR = 1.16), lost job-related income (OR = 1.14), and had a hard time obtaining resources (OR = 1.16) because of the pandemic. No significant differences related to rural or urban residence were observed. CONCLUSION: The findings highlight the need for pragmatic responses that are attuned to differences by providing more equitable access to resources for families. The findings suggest that strategies addressing family worry, obtaining job-related income support, and helping families obtain tangible resources may positively affect family psychological health. As population changes in vaccination rates and COVID variants emerge, reassessment of family and community impact seems indicated. Limitations and future research directions are discussed.


Assuntos
COVID-19 , Humanos , Criança , Pandemias , SARS-CoV-2 , Renda , Cuidadores
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