RESUMEN
The natural abundance of stable carbon and nitrogen isotopes (δ13C and δ15N) in leaves can provide comprehensive information on the physiological and ecological processes of plants and has been widely used in ecological research. However, recent studies on leaf δ13C and δ15N have focused mainly on woody species, few studies have been conducted on herbs in different vegetation types, and their differences and driving factors are still unclear. In this study, we focused on the herbs in subalpine coniferous forests, alpine shrublands, and alpine mea-dows on the eastern Qinghai-Tibet Plateau, and investigated the differences in leaf δ13C and δ15N of herbs and the driving factors. The results showed that there were significant differences in leaf δ13C and δ15N values of herbs among different vegetation types, with the highest δ13C and δ15N values in alpine meadows, followed by alpine shrublands, and the lowest in subalpine coniferous forests. Using variation partitioning analysis, we revealed that differences in leaf δ13C and δ15N of herbs among various vegetation types were driven by both leaf functional traits and climate factors, with the contribution of leaf functional traits being relatively higher than that of climate factors. Hierarchical partitioning results indicated that mean annual temperature (MAT), chlorophyll content index, leaf nitrogen content per unit area (Narea), and leaf mass per area were the main drivers of leaf δ13C variations of herbs across different vegetation types, while the relative importance of Narea and MAT for variation in leaf δ15N of herbs was much higher than those other variables. There was a strong coupling relationship between leaf δ13C and δ15N as indicated by the result of the ordinary least squares regression. Our findings could provide new insights into understanding the key drivers of leaf δ13C and δ15N variations in herbs across different vegetation types.
Asunto(s)
Isótopos de Carbono , Ecosistema , Isótopos de Nitrógeno , Hojas de la Planta , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Isótopos de Nitrógeno/análisis , Isótopos de Carbono/análisis , Tibet , China , Bosques , Altitud , Árboles/crecimiento & desarrollo , Árboles/metabolismo , Árboles/química , Tracheophyta/crecimiento & desarrollo , Tracheophyta/química , Tracheophyta/metabolismo , Pradera , Poaceae/crecimiento & desarrollo , Poaceae/química , Poaceae/metabolismoRESUMEN
OBJECTIVE: To investigate the incidence and prognosis of drug-induced acute renal failure (ARF) in Shanghai. METHODS: The registration forms of ARF patients admitted in 17 hospitals of and over the middle class in Shanghai from January 1, 2004 to December 31, 2006 were screened prospectively. The data, such as epidemiology, survival, mortality, and morbidity were analyzed. RESULTS: 347 of the 1200 ARF patients (28.9%), 224 males and 123 females, aged (58+/-20), suffered from drug-induced ARF. 51.0% of the 347 patients were older than 60. 60.2% of the drug-induced ARF in the non-surgical departments were community-acquired, while 55.7% of the drug-induced ARF in the surgical departments were hospital-acquired. Among the non-surgical departments, the incidence of hospital-acquired drug-induced ARF was the lowest in the department of nephrology (9.5%), while higher in the departments of hematology, cardiology, and neurology, and among the surgical departments, it was the lowest in department of renal surgery, while higher in the departments of liver transplantation, neurosurgery, and cardiovascular surgery. The most common complication was chronic kidney disease (CKD) (n=69, 19.9%), followed by cerebrovascular disease (n=59, 17.0%), diabetes mellitus (n=43, 12.4%), and hypertension (n=41, 11.8%). Renal biopsy showed acute tubular necrosis (18, 37.5%), acute interstitial nephritis (11, 22.9%), and acute infectious tubulo-interstitial nephritis (6, 12.5%). Antibiotics (47.8%) were the head causes of drug-induced ARF, especially aminoglycoside (17.0%) and cephalosporins (12.7%), followed by diuretics (22.2%) and radiocontrasts (13.3%). 22.5% of the drug-induced ARF patients had used two or more drugs. 119 patients (34.3%) needed renal replacement treatment. 100 of the 347 patients (28.8%) died. 188 of the surviving patients (54.2%) had their renal function recovered completely, the renal function of 42 of them (12.1%) was recovered partially, and 17 of then (4.9%) required dialysis when discharged. CONCLUSION: Drug-induced ARF is common with higher incidence in the patients with complications. Antibiotics, diuretic agents, and contrast medium are the main causes.
Asunto(s)
Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/epidemiología , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , China/epidemiología , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
OBJECTIVE: To investigate the prognosis after orthotopic liver transplantation (OLT), and to elucidate the risk factors of poor prognosis in these patients. METHODS: Adult recipients of OLT in Renji Hospital of Shanghai Jiaotong University were retrospectively analyzed. Data in pre-, intra- and post-OLT periods of these patients were collected. Acute kidney injury net (AKIN) criteria were used to analyze the post-OLT acute kidney injury (AKI). By following up all the patients for over a year, Kaplan-Meier survival analysis was used to evaluate the prognosis within 28 days and 1 year. Cox regression analysis was performed to evaluate risk factors of patient death, especially the influence of AKI on patient prognosis. RESULTS: There were 193 patients enrolled, the average age was (48.07+/-10.02) years old. The ratio of male to female was 4:1. One hundred and sixteen patients (60.1%) were found to have AKI after OLT. Twenty-eight-day mortality of post-OLT AKI patients was higher than that without AKI patients [15.5%(18/116) vs. 0, P<0.05], 1 year survival rate of post-OLT AKI patients was lower than that without AKI patients [(70.7% (82/116) vs. 90.9 (70/77), P<0.05). Kaplan-Meier survival analysis showed the survival rate of non-AKI (77 patients), AKI stage 1, 2 and 3 patients (58, 25 and 33 patients respectively) post-OLT were 90.9%, 81.0%, 84.0% and 42.4%, respectively. All the non-survivors were discovered to have AKI within 28 days post-OLT. Cox regression analysis showed pre-OLT hypertension [hazard ratio (HR)=4.398, 95% confidence interval (CI)ú 1.535-12.604, P=0.006], post-OLT AKI (HR=12.100, 95%CI: 1.565-93.540, P=0.017), infection (HR=4.709, 95%CI: 1.813-12.226, P=0.001) and acute physiology and chronic health evaluation II (APACHE II) score > or =10 (HR=3.627, 95%CI: 1.244-10.573, P=0.018) were risk factors of 1 year death. CONCLUSION: AKI is an independent risk factor of poor prognosis after liver transplantation. Prevention of AKI may improve the survival rate of OLT patients.