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1.
《Chronobiology international》2013,30(2):159-165
Orcadian and circatrigintan time series of salivary progesterone levels in premenarchal and adolescent girls and healthy mature premenopausal women have been investigated as a possible determinant for breast cancer risk. Circadian variations in progesterone appear to be more random than systematic and estimates of total daily progesterone output are better represented by samples pooled from several 2-hr specimens. Different patterns of circatrigintan progesterone secretion in girls are recognised and relate to those experienced in infertile and fertile women, though their relation to chronological or menarchal age is as yet uncertain. These data suggest that the measurement of salivary progesterone at premenarche, adolescence and maturity is a feasible, though statistically difficult, study for prospective identification of individuals at risk for breast cancer. 相似文献
2.
ContextModerate-grained data may not always represent landscape structure in adequate detail which could cause misleading results. Certain metrics have been shown to be predictable with changes in scale; however, no studies have verified such predictions using independent fine-grained data.ObjectivesOur objective was to use independently derived land cover datasets to assess relationships between metrics based on fine- and moderate-grained data for a range of analysis extents. We focus on metrics that previous literature has shown to have predictable relationships across scales.MethodsThe study area was located in eastern Connecticut. We compared a 1 m land cover dataset to a 30 m resampled dataset, derived from the 1 m data, as well as two Landsat-based datasets. We examined 11 metrics which included cover areas and patch metrics. Metrics were analyzed using analysis extents ranging from 100 to 1400 m in radius.ResultsThe resampled data had very strong linear relationships to the 1 m data, from which it was derived, for all metrics regardless of the analysis extent size. Landsat-based data had strong correlations for most cover area metrics but had little or no correlation for patch metrics. Increasing analysis areas improved correlations.ConclusionsRelationships between coarse- and fine-grained data tend to be much weaker when comparing independent land cover datasets. Thus, trends across scales that are found by resampling land cover are likely to be unsuitable for predicting the effects of finer-scale elements in the landscape. Nevertheless, coarser data shows promise in predicting fine-grained for cover area metrics provided the analysis area used is sufficiently large. 相似文献
3.
Sequential medical trials involving paired data 总被引:2,自引:0,他引:2
4.
Benjamin C. Blum Weiwei Lin Matthew L. Lawton Qian Liu Julian Kwan Isabella Turcinovic Ryan Hekman Pingzhao Hu Andrew Emili 《Molecular & cellular proteomics : MCP》2022,21(1):100189
Metabolism is recognized as an important driver of cancer progression and other complex diseases, but global metabolite profiling remains a challenge. Protein expression profiling is often a poor proxy since existing pathway enrichment models provide an incomplete mapping between the proteome and metabolism. To overcome these gaps, we introduce multiomic metabolic enrichment network analysis (MOMENTA), an integrative multiomic data analysis framework for more accurately deducing metabolic pathway changes from proteomics data alone in a gene set analysis context by leveraging protein interaction networks to extend annotated metabolic models. We apply MOMENTA to proteomic data from diverse cancer cell lines and human tumors to demonstrate its utility at revealing variation in metabolic pathway activity across cancer types, which we verify using independent metabolomics measurements. The novel metabolic networks we uncover in breast cancer and other tumors are linked to clinical outcomes, underscoring the pathophysiological relevance of the findings. 相似文献
5.
《Endocrine practice》2021,27(11):1156-1164
ObjectiveTo provide a review of the impact of high deductible health plans (HDHPs) on the utilizations of services required for optimal management of diabetes and subsequent health outcomes.MethodsSystematic literature review of studies published between January 1, 2000, and May 7, 2021, was conducted that examined the impact of HDHP on diabetes monitoring (eg, recommended laboratory and surveillance testing), routine care (eg, ambulatory appointments), medication management (eg, medication initiation, adherence), and acute health care utilization (eg, emergency department visits, hospitalizations, incident complications).ResultsOf the 303 reviewed articles, 8 were relevant. These studies demonstrated that HDHPs lower spending at the expense of reduced high-value diabetes monitoring, routine care, and medication adherence, potentially contributing to the observed increases in acute health care utilization. Additionally, patient out-of-pocket costs for recommended screenings doubled, and total health care expenditures increased by 49.4% for HDHP enrollees compared with enrollees in traditional health plans. Reductions in disease monitoring and routine care and increases in acute health care utilization were greatest in lower-income patients. None of the studies examined the impact of HDHPs on access to diabetes self-management education, technology use, or glycemic control.ConclusionAlthough HDHPs reduce some health care utilization and costs, they appear to do so at the expense of limiting high-value care and medication adherence. Policymakers, providers, and payers should be more cognizant of the potential for negative consequences of HDHPs on patients’ health. 相似文献
6.
An Extreme Value Analysis of Pollutant Concentrations in Surface Soils Due to Atmospheric Deposition
Risk assessments often rely on deterministic models using long-term averages or “steady-state” values of input variables. Such models do not provide the information needed to estimate acute exposures. This study uses extreme value theory to examine the frequency and magnitude of daily pollutant concentrations in surface soils predicted at six U.S. locations. Concentrations are predicted using a deposition-leaching model and 50 years of historical precipitation data. A stochastic model also is used to generate 1000 years of precipitation data as modeling inputs for each location. The annual maximum concentrations at each site are fitted to a Gumbel type I distribution to estimate occurrence probability. For soluble pollutants, the predicted concentration varied substantially with precipitation, and the maximum daily concentrations exceeded annual averages by 4 to 8 times. Observed and synthetic precipitation data produced similar results at most study locations, though the synthetic data provided a slightly better fit to the Gumbel type I distribution. The precipitation model allows the generation of representative precipitation data that extend limited historical records. The extreme value analysis facilitates the evaluation of maximum pollutant concentrations, return periods, and other statistics that are important in evaluating acute exposures. 相似文献
7.
《Molecular & cellular proteomics : MCP》2020,19(1):142-154
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- •Flow cytometry analysis is used to isolate ASC speck(+) NPC cells.
- •Proteome analysis of ASC speck(+) NPC cells reveals enriched mitochondrial OxPhos proteins.
- •OxPhos proteins mediate NLRP3 inflammasome activation through mtROS.
- •OxPhos proteins, NDUFB8 and ATP5B are correlated with NPC local recurrence.
8.
Comment on: Rokavec M, et al. Mol Cell 2012; 45:777-89. 相似文献
9.
BackgroundNeuroblastoma, the most common extracranial solid tumor in children, contributes disproportionately to childhood cancer mortality and few risk factors have been identified. Our objective was to evaluate associations between parental and infant characteristics and neuroblastoma incidence.MethodsChildren born in Texas between January 1995 and December 2011 were eligible for the present study. Cases (N = 637) were diagnosed with neuroblastoma in Texas during the same period; controls (N = 6370) matched on year of birth were randomly selected from birth certificates that did not link to a record in the Texas Cancer Registry. We obtained data on birth and parental demographic/reproductive characteristics from birth certificates, and estimated odds ratios (OR) and 95% confidence intervals (CIs) for neuroblastoma using logistic regression.ResultsGestational age 34–36 weeks at birth was associated with neuroblastoma (OR 1.45, CI 1.09–1.90), whereas female sex was inversely associated (OR 0.68, CI 0.58–0.81). Relative to children of non-Hispanic White women, children of Hispanic (OR 0.53, CI 0.43–0.64) or non-Hispanic Black (OR 0.52, CI 0.38–0.71) women were at reduced odds of neuroblastoma. When maternal and paternal race/ethnicity were evaluated jointly, similar patterns were observed (two non-Hispanic Black parents: OR 0.55, 95%CI 0.36–0.79; two Hispanic parents: OR 0.53, 95%CI 0.41–0.67). Older maternal age was also positively associated with neuroblastoma (OR 1.41, CI 1.04–1.90 for 35–39 years; OR 1.62, CI 0.87–2.81 for ≥40 years, relative to 25–29 years).ConclusionsFindings provide further evidence of racial/ethnic disparities in neuroblastoma incidence, determinants of which are unknown. In contrast to most published studies, we observed an association between maternal age and neuroblastoma. Further studies with more robust control for confounding are warranted. 相似文献
10.
《Journal of molecular biology》2021,433(17):166665
Transient receptor potential melastatin 4 (TRPM4) is a broadly expressed Ca2+ activated monovalent cation channel that contributes to the pathophysiology of several diseases.For this study, we generated stable CRISPR/Cas9 TRPM4 knockout (K.O.) cells from the human prostate cancer cell line DU145 and analyzed the cells for changes in cancer hallmark functions. Both TRPM4-K.O. clones demonstrated lower proliferation and viability compared to the parental cells. Migration was also impaired in the TRPM4-K.O. cells. Additionally, analysis of 210 prostate cancer patient tissues demonstrates a positive association between TRPM4 protein expression and local/metastatic progression. Moreover, a decreased adhesion rate was detected in the two K.O. clones compared to DU145 cells.Next, we tested three novel TRPM4 inhibitors with whole-cell patch clamp technique for their potential to block TRPM4 currents. CBA, NBA and LBA partially inhibited TRPM4 currents in DU145 cells. However, none of these inhibitors demonstrated any TRPM4-specific effect in the cellular assays.To evaluate if the observed effect of TRPM4 K.O. on migration, viability, and cell cycle is linked to TRPM4 ion conductivity, we transfected TRPM4-K.O. cells with either TRPM4 wild-type or a dominant-negative mutant, non-permeable to Na+. Our data showed a partial rescue of the viability of cells expressing functional TRPM4, while the pore mutant was not able to rescue this phenotype. For cell cycle distribution, TRPM4 ion conductivity was not essential since TRPM4 wild-type and the pore mutant rescued the phenotype.In conclusion, TRPM4 contributes to viability, migration, cell cycle shift, and adhesion; however, blocking TRPM4 ion conductivity is insufficient to prevent its role in cancer hallmark functions in prostate cancer cells. 相似文献