Positive Correlation Positive Correlation
Introduction Estrogen receptor-Îą (ER) and human epidermal growth factor receptor 2 (HER2) positivity are inversely correlated by standard criteria. However, we investigated the quantitative relation between ER and HER2 expression at both RNA and protein levels in HER2+ve and HER2-ve breast carcinomas.
A relationship between two variables in which both variables move in tandem. A positive correlation exists when as one variable decreases, the other variable also decreases and vice versa. In statistics, a perfect positive correlation is represented by the value +1.00, while a 0.00 indicates no correlation and a -1.00 indicates a perfect negative correlation. For example, a positive correlation would result if I plotted the daytime high temperature with the number of homes in town that ran their AC that day. The hotter it is, the more people there would be who would turn on the cold air, while lower temperatures would result in fewer ACs running. Know More About Compound Interest Calculator Math.Tutorvista.com
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A negative correlation would occur if I plotted the daytime high temperature with the number of homes who turned on their heater. The lower the temperature, the more heaters running, while a higher the temperature would result in fewer heaters being turned on. A constant correlation usually reflects a faulty sample. For example, if I want to compare age and height among children I could measure their heights and ask them their ages. If I plotted the resulting points and found that I had various heights, but all the ages were 10 yrs old, I would have a straight line on the graph. This would also tell me that when I collected the data, I hadn't asked a variety of kids to let me check their heights -- I had only asked 10 year olds Identifying the mechanisms determining species-specific life spans is a central challenge in understanding the biology of aging. Cellular stresses produce damage, that may accumulate and cause aging. Evolution theory predicts that long-lived species secure their longevity through investment in a more durable soma, including enhanced cellular resistance to stress. To investigate whether cells from long-lived species have better mechanisms to cope with oxidative and non-oxidative stress, we compared cellular resistance of primary skin fibroblasts from eight mammalian species with a range of life spans. Cell survival was measured by the thymidine incorporation assay following stresses induced by paraquat, hydrogen peroxide, tert-butyl hydroperoxide, sodium arsenite and alkaline pH (sodium hydroxide). Significant positive correlations between cell LD90 and maximum life span were found for all these stresses. Learn More Factoring calculator Math.Tutorvista.com
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Similar results were obtained when cell survival was measured by the MTT assay, and when lymphocytes from different species were compared. Cellular resistance to a variety of oxidative and non-oxidative stresses was positively correlated with mammalian longevity. Our results support the concept that the gene network regulating the cellular response to stress is functionally important in aging and longevity. Methods ER and HER2 levels were assessed with immunohistochemistry (IHC) and (for HER2) fluorescent in situ hybridization (FISH) and by quantitative reverse transcription-polymerase chain reaction (q-RT-PCR) in formalin-fixed primary breast cancers from 448 patients in the National Cancer Research Institute (NCRI) Adjuvant Breast Cancer Trial (ABC) tamoxifenonly arm. Relations at the RNA level were assessed in 1,139 TransATAC tumors. Results ER and HER2 RNA levels were negatively correlated as expected in HER2+ve (IHC 3+ and/or FISH-amplified) tumors (r = -0.45; P = 0.0028). However, in HER2-ve tumors (ER+ve and ERve combined), a significant positive correlation was found (r = 0.43; P < 0.0001), HER2 RNA levels being 1.74-fold higher in ER+ve versus ER-ve tumors. This correlation was maintained in the ER+veHER2-ve subgroup (r = 0.24; P = 0.0023) and confirmed in this subgroup in 1,139 TransATAC tumours (r = 0.25; P < 0.0001). The positive relation extended to IHC-detected ER in ABC: mean ± 95% confidence interval (CI) H-scores were 90 ± 19 and 134 ± 19 for 0 and 1+ HER2 IHC categories, respectively (P = 0.0013). A trend toward lower relapse-free survival (RFS) was observed in patients with the lowest levels of ER and HER2 RNA levels within the ER+veHER2-ve subgroup both for ABC and TransATAC cohorts.
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Published on May 26, 2012
The hotter it is, the more people there would be who would turn on the cold air, while lower temperatures would result in fewer ACs running....