Detection of initial angiogenesis from dorsal aorta into metanephroi and elucidation of its role in kidney development

AbstractReconstruction of blood vessels is considered the most difficult part for the complicated organs, therefore, blood vessel construction is regarded as a key point for kidney regeneration in vitro. Vasculogenesis and angiogenesis are the two mechanisms to form blood vessels in embryonic organs, and most studies resided in vaculogenesis. Angiogenesis resided mostly in adult diseases such as wound healing, growth of tumors, and psoriasis diseases. However, renal angiogenesis is simply attributed to the sprouting of pre-existing blood vessel from dorsal aorta into metanephroi, and its occurrence is considered to be at a late stage of metanephric development. Since no techniques are available for delicate detection, the initial angiogenesis from dorsal aorta into metanephroi as well as its role in kidney development still remained unclear. In this study, we developed a method to detect the initial angiogenesis of dorsal aorta into metanephroi, and firstly clarified that dorsal aorta angiogenesis occurred at an early stage of metanephric development. We also elucidated the role of dorsal aorta angiogenesis in promoting the early blood vessel formation, tubule formation and glomeruli maturation. It is suggested that blood flow and dynamic circulation of various factors at the early developing stage may be prerequisite to a successful construction of blood vessels in the complicated organs either in vitro or in vivo. These findings contribute to a better understanding of dorsal aorta angiogenesis during kidney development and shed light on its significant value for the application of tissue engineering to complicated organs

Taiwan Oscillation Network

The Taiwan Oscillation Network (TON) is a ground-based network to measure solar intensity oscillations to study the internal structure of the Sun. K-line full-disk images of 1000 pixels diameter are taken at a rate of one image per minute. Such data would provide information onp-modes withl as high as 1000. The TON will consist of six identical telescope systems at proper longitudes around the world. Three telescope systems have been installed at Teide Observatory (Tenerife), Huairou Solar Observing Station (near Beijing), and Big Bear Solar Observatory (California). The telescopes at these three sites have been taking data simultaneously since October of 1994. Anl – v diagram derived from 512 images is included to show the quality of the data

Recurrent disturbances and the degradation of hard coral communities in Taiwan

Recurrent disturbances can have a critical effect on the structure and function of coral reef communities. In this study, long-term changes were examined in the hard coral community at Wanlitung, in southern Taiwan, between 1985 and 2010. In this 26 year interval, the reef has experienced repeated disturbances that include six typhoons and two coral-bleaching events. The frequency of disturbance has meant that species susceptible to disturbance, such as those in the genus Acropora and Montipora have almost disappeared from the reef. Indeed, almost all hard coral species have declined in abundance, with the result that total hard coral cover in 2010 (17.7%) was less than half what it was in 1985 (47.5%). In addition, macro-algal cover has increased from 11.3% in 2003 to 28.5% in 2010. The frequency of disturbance combined with possible chronic influence of a growing human population mean that a diverse reef assemblage is unlikely to persist on this reef into the future

Preoperative Proteinuria Is Associated with Long-Term Progression to Chronic Dialysis and Mortality after Coronary Artery Bypass Grafting Surgery

AIMS: Preoperative proteinuria is associated with post-operative acute kidney injury (AKI), but whether it is also associated with increased long-term mortality and end-stage renal disease (ESRD) is unknown. METHODS AND RESULTS: We studied 925 consecutive patients undergoing CABG. Demographic and clinical data were collected prospectively, and patients were followed for a median of 4.71 years after surgery. Proteinuria, according to dipstick tests, was defined as mild (trace to 1+) or heavy (2+ to 4+) according to the results of the dipstick test. A total of 276 (29.8%) patients had mild proteinuria before surgery and 119 (12.9%) patients had heavy proteinuria. During the follow-up, the Cox proportional hazards model demonstrated that heavy proteinuria (hazard ratio [HR], 27.17) was an independent predictor of long-term ESRD. There was a progressive increased risk for mild proteinuria ([HR], 1.88) and heavy proteinuria ([HR], 2.28) to predict all-cause mortality compared to no proteinuria. Mild ([HR], 2.57) and heavy proteinuria ([HR], 2.70) exhibited a stepwise increased ratio compared to patients without proteinuria for long-term composite catastrophic outcomes (mortality and ESRD), which were independent of the baseline GFR and postoperative acute kidney injury (AKI). CONCLUSION: Our study demonstrated that proteinuria is a powerful independent risk factor of long-term all-cause mortality and ESRD after CABG in addition to preoperative GFR and postoperative AKI. Our study demonstrated that proteinuria should be integrated into clinical risk prediction models for long-term outcomes after CABG. These results provide a high priority for future renal protective strategies and methods for post-operative CABG patients

Advanced age affects the outcome-predictive power of RIFLE classification in geriatric patients with acute kidney injury

The RIFLE (risk, injury, failure, loss, and end-stage) classification is widely used to gauge the severity of acute kidney injury, but its efficacy has not been formally tested in geriatric patients. To correct this we conducted a prospective observational study in a multicenter cohort of 3931 elderly patients (65 years of age or older) who developed acute kidney injury in accordance with the RIFLE creatinine criteria after major surgery. We studied the predictive power of the RIFLE classification for in-hospital mortality and investigated the potential interaction between age and RIFLE classification. In general, the survivors were significantly younger than the nonsurvivors and more likely to have hypertension. In patients 76 years of age and younger, RIFLE-R, -I, or -F classifications were significantly associated with increased hospital mortality in a stepwise manner. There was no significant difference, however, in hospital mortality in those over 76 years of age between patients with RIFLE-R and RIFLE-I, although RIFLE-F patients had significantly higher mortality than both groups. Thus, the less severe categorizations of acute kidney injury per RIFLE classification may not truly reflect the adverse impact on elderly patients

The role of ERK5 in endothelial cell function

Extracellular-signal-regulated kinase 5 (ERK5), also termed big MAPK1 (BMK1), is the most recently discovered member of the mitogen-activated protein kinase (MAPK) family. It is expressed in a variety of tissues and is activated by a range of growth factors, cytokines and cellular stresses. Targeted deletion of Erk5 in mice has revealed that the ERK5 signalling cascade is critical for normal cardiovascular development and vascular integrity. In vitro studies have revealed that, in endothelial cells, ERK5 is required for preventing apoptosis, mediating shear-stress signalling and regulating tumour angiogenesis. The present review focuses on our current understanding of the role of ERK5 in regulating endothelial cell function

Acute-on-chronic kidney injury at hospital discharge is associated with long-term dialysis and mortality

Existing chronic kidney disease (CKD) is among the most potent predictors of postoperative acute kidney injury (AKI). Here we quantified this risk in a multicenter, observational study of 9425 patients who survived to hospital discharge after major surgery. CKD was defined as a baseline estimated glomerular filtration rate <45ml/min per 1.73m2. AKI was stratified according to the maximum simplified RIFLE classification at hospitalization and unresolved AKI defined as a persistent increase in serum creatinine of more than half above the baseline or the need for dialysis at discharge. A Cox proportional hazard model showed that patients with AKI-on-CKD during hospitalization had significantly worse long-term survival over a median follow-up of 4.8 years (hazard ratio, 3.3) than patients with AKI but without CKD. The incidence of long-term dialysis was 22.4 and 0.17 per 100 person-years among patients with and without existing CKD, respectively. The adjusted hazard ratio for long-term dialysis in patients with AKI-on-CKD was 19.8 compared to patients who developed AKI without existing CKD. Furthermore, AKI-on-CKD but without kidney recovery at discharge had a worse outcome (hazard ratios of 4.6 and 213, respectively) for mortality and long-term dialysis as compared to patients without CKD or AKI. Thus, in a large cohort of postoperative patients who developed AKI, those with existing CKD were at higher risk for long-term mortality and dialysis after hospital discharge than those without. These outcomes were significantly worse in those with unresolved AKI at discharge