Faculty Bibliography
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176
Short-Term Adverse Effects of Austerity Policies on Mortality Rates: What Could Their Real Magnitude Be? [Comment]
PMID: 29995467
ISSN: 1541-0048
CID: 4214292
Blood Concentrations of Persistent Organic Pollutants and Unhealthy Metabolic Phenotypes in Normal-Weight, Overweight, and Obese Individuals
Factors underlying metabolic phenotypes, such as the metabolically healthy but obese phenotype, remain unclear. Differences in metabolic phenotypes-particularly, among individuals with a similar body mass index-could be related to concentrations of persistent organic pollutants (POPs). To our knowledge, no studies have analyzed POPs and metabolic phenotypes in normal-weight persons. We investigated the relationships between serum concentrations of POPs and metabolic phenotypes in 860 normal-weight, overweight, and obese participants in the 2002 Catalan Health Interview Survey (Spain). POP concentrations were significantly higher in metabolically unhealthy than in metabolically healthy individuals. In models adjusting for body mass index and other confounders, hexachlorobenzene, β-hexachlorocyclohexane, and polychlorinated biphenyls were associated with the unhealthy metabolic phenotype and metabolic syndrome. Among normal-weight individuals, the adjusted prevalence ratio of having an unhealthy phenotype for the upper category of the sum of orders of the 6 mentioned POPs (all individually associated with metabolic phenotypes) was 4.1 (95% confidence interval: 1.7, 10.0). Among overweight and obese individuals, the corresponding prevalence ratio for the sum of polychlorinated biphenyls was 1.4 (95% confidence interval: 1.0, 1.8). Our results supported the hypothesis that POP concentrations are associated with unhealthy metabolic phenotypes, not only in obese and overweight individuals but also (and probably more strongly) in normal-weight individuals.
PMID: 29106481
ISSN: 1476-6256
CID: 4214262
The Association of Recently Diagnosed Diabetes and Long-term Diabetes With Survival in Pancreatic Cancer Patients: A Pooled Analysis
OBJECTIVES:It is unclear whether long-standing diabetes or new-onset pancreatogenic diabetes contributes to poor prognosis in patients with pancreatic ductal adenocarcinoma (PDAC). METHODS:We investigated the influence of diabetes diagnosed shortly before PDAC and long-term diabetes on overall survival in 2792 PDAC patients who had participated in 3 PDAC case-control studies in the Pancreatic Cancer Case-Control Consortium. There were 300 patients with long-term diabetes of more than 3 years' duration (11%) and 418 patients with recently diagnosed diabetes of 3-year duration or less (15%). We performed Cox regression to determine the association of long-term diabetes and recently diagnosed diabetes with overall survival, adjusting for study site, age, sex, race, stage of disease, surgery, chemotherapy, smoking history, and body mass index at diagnosis. RESULTS:In the overall population, neither long-term diabetes (hazard ratio [HR], 1.10; 95% confidence interval [CI], 0.97-1.26) nor recently diagnosed diabetes (HR, 1.06; 95% CI, 0.94-1.18) was associated with shorter survival. When stratified by stage of disease, long-term diabetes was associated with 42% increase in rate of death in persons with resectable PDAC (HR, 1.42; 95% CI, 1.13-1.78), whereas it was not associated with survival in PDAC patients with more advanced disease. CONCLUSION:Long-term diabetes was associated with increased rate of death in patients with resectable PDAC.
PMCID:5807116
PMID: 29401167
ISSN: 1536-4828
CID: 4214282
Genome-wide meta-analysis identifies five new susceptibility loci for pancreatic cancer
In 2020, 146,063 deaths due to pancreatic cancer are estimated to occur in Europe and the United States combined. To identify common susceptibility alleles, we performed the largest pancreatic cancer GWAS to date, including 9040 patients and 12,496 controls of European ancestry from the Pancreatic Cancer Cohort Consortium (PanScan) and the Pancreatic Cancer Case-Control Consortium (PanC4). Here, we find significant evidence of a novel association at rs78417682 (7p12/TNS3, P = 4.35 × 10-8). Replication of 10 promising signals in up to 2737 patients and 4752 controls from the PANcreatic Disease ReseArch (PANDoRA) consortium yields new genome-wide significant loci: rs13303010 at 1p36.33 (NOC2L, P = 8.36 × 10-14), rs2941471 at 8q21.11 (HNF4G, P = 6.60 × 10-10), rs4795218 at 17q12 (HNF1B, P = 1.32 × 10-8), and rs1517037 at 18q21.32 (GRP, P = 3.28 × 10-8). rs78417682 is not statistically significantly associated with pancreatic cancer in PANDoRA. Expression quantitative trait locus analysis in three independent pancreatic data sets provides molecular support of NOC2L as a pancreatic cancer susceptibility gene.
PMCID:5805680
PMID: 29422604
ISSN: 2041-1723
CID: 2947002
Neurotoxic chemicals in adipose tissue: A role in puzzling findings on obesity and dementia
Midlife obesity is associated with increased risk of dementia, whereas late-life obesity is commonly associated with a lower risk of dementia. Although methodologic issues are often discussed in this apparent risk reversal, chronic exposure to low-dose organochlorine pesticides (OCPs), an emerging risk factor for dementia in general populations, may contribute to a direct explanation for these differences. OCPs are strong lipophilic chemicals with very long half-lives (several years), primarily stored in adipose tissue and very slowly released and metabolized over years. As serum concentrations of neurotoxic OCPs strongly correlate with brain OCPs (r = 0.95), any condition enhancing the release of OCPs from the adipose tissue into circulation would increase the risk of dementia. Increased release of OCPs from adipose tissue typically occurs in (1) dysfunctional adipocytes accompanied by uncontrolled lipolysis and (2) weight loss. Weight gain may help sequester circulating OCPs in adipose tissue. As obesity is the most common reason that adipocytes become dysfunctional, midlife obesity can increase dementia risk through the chronic release of OCPs into circulation. However, late-life obesity potentially decreases dementia risk because weight loss after midlife will increase the release of OCPs while weight gain may actually decrease the release. These countervailing forces may underlie paradoxical associations with dementia of obesity in midlife vs late life which is influenced by weight change after midlife. This hypothesis should be tested in future experimental and human studies on obesity and dementia.
PMCID:5798659
PMID: 29358509
ISSN: 1526-632x
CID: 4214272
Citizens' perceptions of the presence and health risks of synthetic chemicals in food: results of an online survey in Spain
OBJECTIVE:To explore factors influencing perceptions and viewpoints on the responsibility for the presence of toxic substances in food, on enforcement of laws and regulations that control human exposure to toxic substances in food, and on the effectiveness of such regulations. METHODS:An online survey was completed by 740 individuals from several parts of Spain (median age, 47 years; 67% were women; 70% had completed university studies). RESULTS:Over 87% of respondents said that it was possible that throughout their lives they could have accumulated in their body toxic substances potentially dangerous to their health. The attribution of the responsibility for toxic substances in food to a larger number of social groups was more frequent among respondents who consulted information about the problem more often (odds ratio [OR]: 1.92), who correctly identified factors that increase the likelihood of toxic substances in food being harmful to human health (OR: 2.86), who better knew the health problems that may be caused by such substances (OR: 2.48), and who recognised more food groups that tend to have concentrations of toxic substances potentially harmful to health (OR: 2.92) (all p values <0.001). Women were 65% less likely than men to answer that regulations on toxic substances in food are effective (p<0.001); and so were participants who identified more food groups with potentially toxic concentrations. CONCLUSIONS:Among study participants there was a widespread scepticism and distrust towards the enforcement and effectiveness of laws and regulations that in Spain aim to control human exposure to toxic substances in food.
PMID: 28666557
ISSN: 1578-1283
CID: 4214252
Changes in the total effective xenoestrogen burden (TEXB) of breast cancer patients during an 18-month post-surgical follow-up
We aimed to assess changes in the total effective xenoestrogen burden (TEXB) -a biomarker of combined effect of mixtures of xenoestrogens- in breast cancer patients at surgery (breast adipose tissue) and at different time points during an 18-month follow-up (abdominal adipose tissue), and to analyze the potential influence of socio-demographic, reproductive, tumor, and treatment characteristics on TEXB levels. TEXB-alpha (due to persistent organohalogenated chemicals) and TEXB-beta (due mainly to endogenous estrogens) were quantified in 44 women. TEXB values significantly increased over follow-up (p <0.001); the largest difference was observed at 6-12 months post-surgery (p <0.001); then decreased over time. TEXB-alpha at 6-18 months was significantly higher in younger patients with estrogen receptor positivity (p=0.034) and in those receiving anti-neoplasm chemotherapy. Cancer treatment may be responsible for the increase in TEXB-alpha observed in patients with hormone-dependent tumors, which may confer to xenoestrogens a role in the progression of the disease.
PMID: 28288811
ISSN: 1873-1708
CID: 4214242
Discourses on the Toxic Effects of Internal Chemical Contamination in Catalonia, Spain
Human exposure to and contamination by environmental toxic compounds generates discourses and practices that merit greater attention. In this article, we assess internal chemical contamination and the risk of toxic effects as an experience related to the production of meaning in everyday life. Drawing on the analysis of semantic networks of narratives from semi-structured interviews conducted with 43 informants in Catalonia, Spain, we consider participants' perceptions of the health risks of toxic compounds, including social discourses on exposure, toxicity, and internal chemical contamination, and on responsibilities, consequences, and proposed strategies for controlling toxic compounds. Informants' narratives on the relationships between nature and nurture suggest that they no longer perceive rigid boundaries separating the human body from the external environment and its chemical pollutants.
PMID: 27142961
ISSN: 1545-5882
CID: 4214212
[The biomonitoring of toxic substances in biological samples of general population]
Many of the world's most developed countries have adopted biomonitoring of toxic substances in order to ascertain their levels in biological samples. These substances get into the body through different environmental exposures. Monitoring toxic substances in biological samples should allow us to ascertain their levels in vulnerable groups, assess their evolution over time, make comparisons with levels observed in other countries, identify groups at risk or with high toxic levels and promote research. The main objective of biomonitoring is to act as a policy design tool to facilitate the implementation of particular measures in various sectors: health, environmental, agricultural and livestock or food industry sectors. In Spain, information on levels of toxic substances of environmental origin is provided by specific studies on health effects from environmental sources, such as the INMA project (INfancia y Medio Ambiente [childhood and environment]). In addition, biomonitoring projects have been implemented in Catalonia and the Canary Islands, together with a national biomonitoring programme in the adult working population. However, further progress is needed to develop a system that covers the general population as well as subgroups at risk, which relies on the collaboration of the involved authorities and the participation of professionals from different sectors and citizen organisations interested in the relationship between health and the environment.
PMID: 27132480
ISSN: 1578-1283
CID: 4214202
Three new pancreatic cancer susceptibility signals identified on chromosomes 1q32.1, 5p15.33 and 8q24.21
Genome-wide association studies (GWAS) have identified common pancreatic cancer susceptibility variants at 13 chromosomal loci in individuals of European descent. To identify new susceptibility variants, we performed imputation based on 1000 Genomes (1000G) Project data and association analysis using 5,107 case and 8,845 control subjects from 27 cohort and case-control studies that participated in the PanScan I-III GWAS. This analysis, in combination with a two-staged replication in an additional 6,076 case and 7,555 control subjects from the PANcreatic Disease ReseArch (PANDoRA) and Pancreatic Cancer Case-Control (PanC4) Consortia uncovered 3 new pancreatic cancer risk signals marked by single nucleotide polymorphisms (SNPs) rs2816938 at chromosome 1q32.1 (per allele odds ratio (OR) = 1.20, P = 4.88x10-15), rs10094872 at 8q24.21 (OR = 1.15, P = 3.22x10-9) and rs35226131 at 5p15.33 (OR = 0.71, P = 1.70x10-8). These SNPs represent independent risk variants at previously identified pancreatic cancer risk loci on chr1q32.1 (NR5A2), chr8q24.21 (MYC) and chr5p15.33 (CLPTM1L-TERT) as per analyses conditioned on previously reported susceptibility variants. We assessed expression of candidate genes at the three risk loci in histologically normal (n = 10) and tumor (n = 8) derived pancreatic tissue samples and observed a marked reduction of NR5A2 expression (chr1q32.1) in the tumors (fold change -7.6, P = 5.7x10-8). This finding was validated in a second set of paired (n = 20) histologically normal and tumor derived pancreatic tissue samples (average fold change for three NR5A2 isoforms -31.3 to -95.7, P = 7.5x10-4-2.0x10-3). Our study has identified new susceptibility variants independently conferring pancreatic cancer risk that merit functional follow-up to identify target genes and explain the underlying biology.
PMCID:5340084
PMID: 27579533
ISSN: 1949-2553
CID: 2232522
