32 research outputs found
Identifying extreme COVID-19 mortality risks in English small areas: a disease cluster approach
The COVID-19 pandemic is having a huge impact worldwide and has highlighted the extent of health inequalities between countries but also in small areas within a country. Identifying areas with high mortality is important both of public health mitigation in COVID-19 outbreaks, and of longer term efforts to tackle social inequalities in health. In this paper we consider different statistical models and an extension of a recent method to analyze COVID-19 related mortality in English small areas during the first wave of the epidemic in the first half of 2020. We seek to identify hotspots, and where they are most geographically concentrated, taking account of observed area factors as well as spatial correlation and clustering in regression residuals, while also allowing for spatial discontinuities. Results show an excess of COVID-19 mortality cases in small areas surrounding London and in other small areas in North-East and and North-West of England. Models alleviating spatial confounding show ethnic isolation, air quality and area morbidity covariates having a significant and broadly similar impact on COVID-19 mortality, whereas nursing home location seems to be slightly less important.This work has been supported by Projects MTM2017-82553-R (AEI/FEDER, UE) and Project PID2020-113125RB-I00/MCIN/AEI/10.13039/501100011033). Funding Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature
Master your Metrics with Calibration
Machine learning models deployed in real-world applications are often
evaluated with precision-based metrics such as F1-score or AUC-PR (Area Under
the Curve of Precision Recall). Heavily dependent on the class prior, such
metrics make it difficult to interpret the variation of a model's performance
over different subpopulations/subperiods in a dataset. In this paper, we
propose a way to calibrate the metrics so that they can be made invariant to
the prior. We conduct a large number of experiments on balanced and imbalanced
data to assess the behavior of calibrated metrics and show that they improve
interpretability and provide a better control over what is really measured. We
describe specific real-world use-cases where calibration is beneficial such as,
for instance, model monitoring in production, reporting, or fairness
evaluation.Comment: Presented at IDA202
Growth Inhibition of Human Gynecologic and Colon Cancer Cells by Phyllanthus watsonii through Apoptosis Induction
Phyllanthus watsonii Airy Shaw is an endemic plant found in Peninsular Malaysia. Although there are numerous reports on the anti cancer properties of other Phyllanthus species, published information on the cytotoxicity of P. watsonii are very limited. The present study was carried out with bioassay-guided fractionation approach to evaluate the cytotoxicity and apoptosis induction capability of the P. watsonii extracts and fractions on human gynecologic (SKOV-3 and Ca Ski) and colon (HT-29) cancer cells. P. watsonii extracts exhibited strong cytotoxicity on all the cancer cells studied with IC50 values of ≤ 20.0 µg/mL. Hexane extract of P. watsonii was further subjected to bioassay-guided fractionation and yielded 10 fractions (PW-1→PW-10). PW-4→PW-8 portrayed stronger cytotoxic activity and was further subjected to bioassay-guided fractionation and resulted with 8 sub-fractions (PPWH-1→PPWH-8). PPWH-7 possessed greatest cytotoxicity (IC50 values ranged from 0.66 – 0.83 µg/mL) and was selective on the cancer cells studied. LC-MS/MS analysis of PPWH-7 revealed the presence of ellagic acid, geranic acid, glochidone, betulin, phyllanthin and sterol glucoside. Marked morphological changes, ladder-like appearance of DNA and increment in caspase-3 activity indicating apoptosis were clearly observed in both human gynecologic and colon cancer cells treated with P. watsonii especially with PPWH-7. The study also indicated that P. watsonii extracts arrested cell cycle at different growth phases in SKOV-3, Ca Ski and HT-29 cells. Cytotoxic and apoptotic potential of the endemic P. watsonii was investigated for the first time by bioassay-guided approach. These results demonstrated that P. watsonii selectively inhibits the growth of SKOV-3, Ca Ski and HT-29 cells through apoptosis induction and cell cycle modulation. Hence, P. watsonii has the potential to be further exploited for the discovery and development of new anti cancer drugs
The role of pannexin 1 in the purinergic regulation of synaptic transmission in mouse motor synapses
The role of pannexin 1 in the release to the extracellular space of ATP/adenosine modulating the acetylcholine (ACh) secretion was studied in mouse diaphragm motor synapses. Using neuromuscular preparations obtained from wild-type and pannexin-1 knockout mice, the miniature endplate potential (MEPPs) and evoked endplate potentials (EPPs) were recorded in combination with pharmacological modulation of P2-type ATP receptors and A1-type adenosine receptors. Selective inhibition of A1 receptors with DPCPX or P2 receptors with PPADS increased quantal content of EPPs in wild-type mice. MRS 2211, selective antagonist of P2Y13 receptors, produced the same effect. Activation of receptors A1 or P2Y13 by their agonists (2-CADO and IDP, respectively) decreased the EPP quantal content. It means that the activity of endogenous ATP and adenosine is synergistic and directed to depression of the ACh release. ARL67156, an inhibitor of synaptic ecto-ATPases, which blocks the hydrolysis of ATP to adenosine and increases the level of ATP in the synaptic cleft, prolonged EPPs without changing their quantal content. In pannexin-1 knockout mice there were no changes in the EPP quantal content and in other parameters of synaptic transmission as compared to wildtype mice. However, downregulation of purinergic effects with antagonists of A1 or P2 receptors (DPCPX, PPADS, MRS 2211) did not change EPP quantal content and any other parameters of spontaneous or evoked ACh release in all cases. ARL67156 did not alter the temporal parameters of EPPs, either. Nevertheless, 2-CADO, the A1-type receptor agonist, decreased the EPP quantal content, while the agonist of P2Y13 receptors decreased the MEPP amplitude. Thus, in mice lacking pannexin 1, procedures revealing the presence and regulatory activity of synaptic ATP/adenosine did not change the parameters of synaptic transmission. The obtained data substantiate a mandatory role of pannexin 1 in the purinergic regulation of motor synapse activity by endogenous ATP/adenosine