RESUMEN
To explore the temporal and spatial variations in phytoplankton community in small estuaries, we collected surface water samples from Yongjiang River estuary during wet, normal, and dry seasons and determined the main driving factors of phytoplankton community. A total of 358 species belonging to nine phyla and 123 genera were identified in all seasons. During wet, normal, and dry seasons, species number was 276, 154 and 151, and the abundance was (170.45±225.43)×103, (51.92±30.28)×103 and (31.65±12.79)×103 cells·L-1, respectively. Diatoms dominated the phytoplankton community, and the main dominant species were Cyclotella meneghiniana, Skeletonema costatum, and Paralia sulcata. Shannon diversity and Pielou evenness indices decreased from inside mouth to outside mouth in wet season, but there was no obvious spatial difference in normal season or dry season. Results of non-metric multidimensional scaling analysis and analysis of similarities showed that phytoplankton community composition differed significantly among different regions (inside, at and outside mouth) and different seasons. In wet season, phytoplankton abundance was significantly positively correlated with temperature, dissolved inorganic nitrogen, and dissolved reactive phosphorus, but significantly negatively correlated with salinity. In normal season, phytoplankton abundance was significantly negatively correlated with temperature. In dry season, it was not significantly correlated with environmental factors. Results of redundancy analysis showed that temperature, salinity, ammonium and dissolved reactive phosphorus explained the variations in phytoplankton community by 19.5%, 11.9%, 9.4% and 8.2%, respectively. These results revealed high dominance of diatoms and the main driving factors (temperature, salinity and nutrients) of phytoplankton community in Yongjiang River estuary.
Asunto(s)
Diatomeas , Estuarios , Fitoplancton , Ríos , Estaciones del Año , Fitoplancton/crecimiento & desarrollo , Fitoplancton/clasificación , China , Diatomeas/crecimiento & desarrollo , Diatomeas/clasificación , Dinámica Poblacional , Análisis Espacio-Temporal , Monitoreo del Ambiente , Ecosistema , Nitrógeno/análisisRESUMEN
Marine biota, especially commercially important species, serves as a basis for human nutrition. However, millions of tons of plastic litter are produced and enter the marine environment every year, with potential adverse impacts on marine organisms. In the present study, we investigated the occurrence and characteristics of microplastic (MP) pollution in the digestive tracts of 13 species of wild nektons from 20 stations sampled in the South China Sea (SCS) and the Indian Ocean (IO), and assessed the human health risks of MPs. The detection rate of MPs ranged from 0.00% to 50.00% from the SCS, which was dramatically lower than that from the IO (10.00-80.00%). The average abundance of MP was 0.18 ± 0.06 items g wet weight-1 (ww-1) in the SCS, which was significantly lower than that in the IO with a concentration of 0.70 ± 0.16 items g ww-1. Most MPs were fibers in type, black in color, and polyester (PES) in polymer composition in both the SCS and IO. Interestingly, distinct profiles of MP pollution were found between the benthic and pelagic nektons: 1) The predominant MP composition was PES in the benthic nektons, whereas polyamide (PA) accounted for a larger part of the total MP count in the pelagic nektons within the SCS; 2) The abundance of MP in the benthic nektons (0.52 ± 0.24 items individual-1) was higher than that in the pelagic nektons (0.30 ± 0.11 items individual-1). Accordingly, the mean hazard score of MPs detected in the benthic nektons (220.66 ± 210.75) was higher than that in the pelagic nektons (49.53 ± 22.87); 3) The mean size of the MP in the pelagic nektons (0.84 ± 0.17 mm) was larger than that in the benthic nektons (0.49 ± 0.09 mm). Our findings highlight the need to further investigate the ecological impacts of MPs on wild nekton, especially commercially important species, and its potential implications for human health.
Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , China , Monitoreo del Ambiente , Humanos , Océano Índico , Plásticos , Contaminantes Químicos del Agua/análisisRESUMEN
Microplastic (MP) pollution is an emerging contaminant in aquatic environments worldwide. Nonetheless, the developmental toxicity of MPs in the early life stages of fish and the mechanisms involved are not yet fully understood. The present study investigated the effects of different concentrations of polystyrene (PS) MPs on the early development of the marine model fish the medaka Oryzias melastigma. Our results showed that waterborne exposure to PS MPs significantly delayed the hatching time, altered the heartbeat and decreased the hatching rate of embryos. Furthermore, the genes involved in cardiac development, encoding for embryo-hatching enzymes, as well as inflammatory responses were significantly upregulated. The transcriptome results showed that mainly the pathways involved in metabolism, immune response, genetic information processing and diseases were significantly enriched. These results demonstrate that PS MPs negatively impact embryogenesis and the immune response of O. melastigma.
Asunto(s)
Oryzias , Contaminantes Químicos del Agua , Animales , Desarrollo Embrionario , Microplásticos , PlásticosRESUMEN
The present study was designed to investigate the prognostic significance of the preoperative sensitive-modified Glasgow prognostic score (S-mGPS) and its superiority in esophageal squamous cell carcinoma (ESCC). Clinicopathologic characteristics, preoperative albumin and C-reactive protein (CRP) levels were retrospectively collected in 442 patients who underwent transthoracic esophagectomy. The S-mGPS was calculated before surgery based on optimal cutoff values of 45.6 g/L for albumin and 10.0 mg/L for CRP. 360, 74 and 8 cases were assigned an mGPS of 0, 1 and 2, respectively. In contrast, the S-mGPS was 0 in 114, 1 in 258 and 2 in 70 patients. Of the 360 patients with an mGPS of 0, 246 migrated to the S-mGPS-1 group. Both mGPS and S-mGPS were significantly correlated with tumor length, depth of invasion, pathological tumor-node-metastasis (pTNM) stage and adjuvant treatment. In addition, they were significantly associated with disease free survival (DFS) and overall survival (OS) in univariate analysis. Furthermore, multivariate Cox regression analysis identified S-mGPS as an independent prognostic indicator for both DFS [hazard ratio (HR), 1.577; 95% confidence interval (CI), 1.149-2.163; P = 0.005] and OS (HR, 1.762; 95% CI, 1.250-2.484; P = 0.001), but not mGPS (HR, 0.957; 95% CI, 0.692-1.323; P = 0.790 for DFS and HR, 1.089; 95% CI, 0.781-1.517; P = 0.615 for OS, respectively). Moreover, subgroup analysis revealed that the prognostic impact of the S-mGPS was especially striking in pTNM stage II patients. The preoperative S-mGPS is superior to the mGPS as a prognostic predictor in patients with resectable ESCC.
Asunto(s)
Biomarcadores de Tumor/sangre , Proteína C-Reactiva/análisis , Carcinoma de Células Escamosas/sangre , Carcinoma de Células Escamosas/mortalidad , Neoplasias Esofágicas/sangre , Neoplasias Esofágicas/mortalidad , Albúmina Sérica/análisis , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Supervivencia sin Enfermedad , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Adulto JovenRESUMEN
The present study was to establish a prognostic indicator based on preoperative fibrinogen and C-reactive protein (CRP) (FC score) in esophageal squamous cell carcinoma (ESCC). Clinicopathologic characteristics, preoperative plasma fibrinogen and serum CRP levels were reviewed in patients who underwent transthoracic esophagectomy. The optimal cut-off value for fibrinogen and CRP was defined as 4.0 g/dL and 10.0 mg/L according to previous reports. Patients with elevated fibrinogen and CRP levels were assigned a score of 2, those with only one of these two abnormalities were allocated a score of 1, and those with neither of the two abnormalities were assigned a score of 0. Preoperative FC score was significantly correlated with degree of differentiation, depth of invasion, tumor-node-metastasis (TNM) stage and modified Glasgow Prognostic Score (mGPS). No significant differences in age, gender, tumor length, tumor location, lymph node status or smoking were identified between groups. Univariate survival analysis demonstrated that high preoperative FC score (1/2) was significantly associated with impaired disease free survival (DFS) [hazard ratio (HR), 1.650; 95% confidence interval (CI), 1.181-2.303; P=0.003] and overall survival (OS) (HR, 1.879; 95% CI, 1.333-2.648; P<0.001), and it remained an independent predictor for both DFS (HR, 1.468; 95% CI, 1.043-2.067; P=0.028) and OS (HR, 2.070; 95% CI, 1.266-3.385; P=0.004) in multivariate Cox regression analysis. Preoperative FC score might represent a new potential marker of worst prognosis that warrants further evaluation in prospective and large cohort studies among ESCC patients who underwent transthoracic esophagectomy.