Application of a Diatom Transfer Function to Quantitative Paleoclimatic Reconstruction — A Case Study of Yunlong Lake, Southwest China

Although diatom records from lake sediments have been used for quantitative paleoclimatic reconstruction, their validity and sensitivity have rarely been tested rigorously. At Yunlong Lake, an alpine lake in Southwest China, we studied the seasonal succession of diatom assemblages to produce a mean surface water temperature (MSWT) transfer function. In addition, based on the spatial distribution of surface diatom assemblages with water depth, we produced a diatom-water depth (WD) transfer function. Combined with the analysis of diatom assemblages in a sediment core (YL2013-A), changes in surface water temperature and water level over the last ∼100 years were quantitatively reconstructed using the diatom-based transfer functions. Comparison with records of regional meteorology and reservoir water capacity revealed that the diatom-based lake water level reconstruction is a sensitive indicator of short-term fluctuations in precipitation, and it also reflects a long-term stepwise rise in water level caused by the impounding and large-scale extension of the reservoir. In addition, the diatom-inferred MSWT is consistent with the changes in air temperature prior to large-scale human disturbance of the site. However, after the extension of the reservoir, although the regional air temperature continued to increase, the water temperature decreased substantially. This suggests that the large increase in lake water volume in the short term led to a decrease in the average water temperature, which in turn led to the occurrence of a diatom bloom in the cold season. The results demonstrate that diatom transfer functions based on modern observations of the same lake has a high environmental sensitivity and can be used for the quantitative reconstruction of regional climate change. Overall, our findings provide a foundation for the use of lake diatom records for quantitative paleoclimatic reconstruction on various timescales

The Role of Peroxisome Proliferator-Activated Receptors in Kidney Diseases

Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear hormone receptor superfamily of ligand-activated transcription factors. Accumulating evidence suggests that PPARs may play an important role in the pathogenesis of kidney disease. All three members of the PPAR subfamily, PPARα, PPARβ/δ, and PPARγ, have been implicated in many renal pathophysiological conditions, including acute kidney injury, diabetic nephropathy, and chronic kidney disease, among others. Emerging data suggest that PPARs may be potential therapeutic targets for renal disease. This article reviews the physiological roles of PPARs in the kidney and discusses the therapeutic utility of PPAR agonists in the treatment of kidney disease.</jats:p

Elevated neutrophil percentage-to-albumin ratio predicts increased all-cause and cardiovascular mortality among individuals with diabetes

Abstract Evidence regarding the neutrophil percentage-to-albumin ratio (NPAR) and mortality risk in diabetes patients is scarce. This study aimed at investigating the prognostic value of NPAR for mortality in patients with diabetes. This retrospective analysis was conducted on 6,962 diabetic patients from the NHANES database. Restricted cubic spline (RCS) was used to visualize the association of the NPAR with mortality risk. Weighted multivariable Cox regression models and subgroup analyses were adopted to assess the association of the NPAR with all-cause and cardiovascular mortality. Time-dependent receiver operating characteristic curve (ROC) analysis was conducted to evaluate the accuracy of the NPAR in predicting survival outcomes. Mediation analysis explored the indirect impact of NPAR on mortality mediated through eGFR. During a median follow-up of 6.7 years, there were 1,804 deaths were recorded, including 602 cardiovascular deaths. The RCS regression showed that NPAR has a J-shaped association with all-cause mortality, and a positive linear association with CVD mortality. Each one-unit increase in NPAR was linked with a 14% and 12% increased risk of all-cause and cardiovascular mortality, respectively. The association was consistent in subgroup analyses based on age, sex, race, BMI, hypertension, CKD, and history of CVD. The time-dependent ROC curve showed the area under the curve of were 0.809 for all-cause mortality, and 0.780 for CVD mortality. In mediation analyses, eGFR partially mediated these relationships. An elevated NPAR is independently associated with increased all-cause and cardiovascular mortality in diabetes patients