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1.
Sci Total Environ ; 931: 172924, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38697550

RESUMEN

The water quality in the drinking water reservoir directly affects people's quality of life and health. When external pollution input is effectively controlled, endogenous release is considered the main cause of water quality deterioration. As the major nitrogen (N) and phosphorus (P) sources in reservoirs, sediment plays a vital role in affecting the water quality. To understand the spatial and temporal variation of N and P in the sediment, this study analyzed the current characteristics and cumulative effects of a semi-humid reservoir, Yuqiao Reservoir, in North China. The N and P concentrations in the reservoir sediment were decreased along the flow direction, while the minimum values were recorded at the central sediment profile. External input and algal deposition were the main factors leading to higher sediment concentrations in the east (Re-E) and west (Re-W) areas of reservoir sediment profiles. According to the long-term datasets, the peaks of both sediment total nitrogen content and deposition rate were observed in the 2010s, which has increased about three times and six times than in the1990s, respectively. Therefore, the increase in phosphorus concentration may be the main reason for eutrophication in water in recent years. The mineralization of organic matter has a significant promoting effect on releasing N and P from sediments, which will intensify eutrophication in water dominated by P and bring huge challenges to water environment management. This study highlights that the current imbalance in N and P inputs into reservoirs and the endogenous P release from sediment will have a significant impact on water quality.

2.
Sci Total Environ ; 923: 171417, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38447725

RESUMEN

The water-level fluctuations zones (WLFZs) are crucial transitional interfaces within river-reservoir systems, serving as hotspots for N2O emission. However, the comprehension of response patterns and mechanisms governing N2O emission under hydrological fluctuation remains limited, especially in karstic canyon reservoirs, which introduces significant uncertainty to N2O flux assessments. Soil samples were collected from the WLFZs of the Hongjiadu (HJD) Reservoir along the water flow direction from transition zone (T1 and T2) to lacustrine zone (T3, T4 and T5) at three elevations for each site. These soil columns were used to conduct simulation experiments under various water-filled pore space gradients (WFPSs) to investigate the potential N2O flux pattern and elucidate the underlying mechanism. Our results showed that nutrient distribution and N2O flux pattern differed significantly between two zones, with the highest N2O fluxes in the transition zone sites and lacustrine zone sites were found at 75 % and 95 % WFPS, respectively. Soil nutrient loss in lower elevation areas is influenced by prolonged impoundment durations. The higher N2O fluxes in the lacustrine zone can be attributed to increased nutrient levels resulting from anthropogenic activities. Furthermore, correlation analysis revealed that soil bulk density significantly impacted N2O fluxes across all sites, while NO3-and SOC facilitated N2O emissions in T1-T2 and T4-T5, respectively. It was evident that N2O production primarily contributed to nitrification in the transition zone and was constrained by the mineralization process, whereas denitrification dominated in the lacustrine zone. Notably, the annual N2O efflux from WLFZs accounted for 27 % of that from the water-air interface in HJD Reservoir, indicating a considerably lower contribution than anticipated. Nevertheless, this study highlights the significance of WLFZs as a vital potential source of N2O emission, particularly under the influence of anthropogenic activities and high WFPS gradient.

3.
Front Med (Lausanne) ; 9: 990538, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36186798

RESUMEN

Objective: Primary orbital lymphoma (POL) accounts for an essential part of adult orbital malignancies. Nevertheless, it remains a relatively rare lymphoid malignancy, accounting for <1% of all non-Hodgkin's lymphoma (NHL) cases. Orbital diffuse large B-cell lymphoma (DLBCL) is one of the most prevalent subtypes of POL that confers the worst outcomes. The prognostic determinants of orbital DLBCL remain unknown. Therefore, a retrospective analysis was conducted by investigating the Surveillance, Epidemiology, and End Results (SEER) database for independent predictive factors for the prognosis of orbital DLBCL. Materials and methods: Using the SEER program, we acquired patient data including demographics, clinical characteristics, and treatment strategies. Our cohort included cases of primary orbital DLBCL diagnosed from 2000 to 2017. We conducted Kaplan-Meier analyses to visualize the overall survival (OS) and cause-specific survival (CSS). The Cox proportional hazard regression models were applied to assess the effects of these prognostic factors on OS and CSS. Results: The present cohort included 332 patients with orbital DLBCL. Age was the most impacted variable by orbital DLBCL. Three independent prognostic variables of orbital DLBCL were identified on diagnosis: advanced age, no radiation treatment, and late-stage (Stage IV). Moreover, patients who underwent chemotherapy demonstrated a greater OS when compared with those who did not. In orbital DLBCL, being unmarried was also a poor prognostic factor. Conclusion: The current study is the largest population-based case series of orbital DLBCL. The age at the time of diagnosis, marital status, absence of chemotherapy or radiotherapy, and tumor stage were all found to be correlated with worse prognosis.

4.
Environ Sci Pollut Res Int ; 28(21): 26617-26627, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33492596

RESUMEN

The increase of affected river reaches by reservoirs has drastically disturbed the original hydrological conditions, and subsequently influenced the nutrient biogeochemistry in the aquatic system, particularly in the cascade reservoir system. To understand the seasonal variation of nitrogen (N) behaviors in cascade reservoirs, hydrochemistry and nitrate dual isotopes (δ15N-NO3- and δ18O-NO3-) were conducted in a karst watershed (Wujiang River) in southwest China. The results showed that NO3--N accounted for almost 90% of the total dissolved nitrogen (TDN) concentration with high average concentration 3.8 ± 0.4 mg/L among four cascade reservoirs. Higher N concentration (4.0 ± 0.8 mg/L) and larger longitudinal variation were observed in summer than in other seasons. The relationship between the variation of NO3--N and dual isotopes in the profiles demonstrated that nitrification was dominated transformation, while assimilation contributed significantly in the epilimnion during spring and summer. The high dissolved oxygen concentration in the present cascade reservoirs system prevented the occurrence of N depletion processes in most of the reservoirs. Denitrification occurred in the oldest reservoir during winter with a rate ranging from 18 to 28%. The long-term record of surface water TDN concentration in reservoirs demonstrated an increase from 2.0 to 3.6 mg/L during the past two decades (~ 0.1 mg/L per year). The seasonal nitrate isotopic signature and continuously increased fertilizer application demonstrated that chemical fertilizer contribution significantly influenced NO3--N concentration in the karst cascade reservoirs. The research highlighted that the notable N increase in karst cascade reservoirs could influence the aquatic health in the region and further investigations were required.


Asunto(s)
Nitratos , Contaminantes Químicos del Agua , China , Monitoreo del Ambiente , Nitratos/análisis , Nitrógeno/análisis , Isótopos de Nitrógeno/análisis , Isótopos de Oxígeno/análisis , Ríos , Estaciones del Año , Contaminantes Químicos del Agua/análisis
5.
Acta Pharmacol Sin ; 42(10): 1610-1619, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33495514

RESUMEN

Septic acute liver injury is one of the leading causes of fatalities in patients with sepsis. Toll-like receptor 4 (TLR4) plays a vital role in response to lipopolysaccharide (LPS) challenge, but the mechanisms underlying TLR4 function in septic injury remains unclear. In this study, we investigated the role of TLR4 in LPS-induced acute liver injury (ALI) in mice with a focus on inflammation and apoptosis. Wild-type (WT) and TLR4-knockout (TLR4-/-) mice were challenged with LPS (4 mg/kg) for 6 h. TLR4 signaling cascade markers (TLR4, MyD88, and NF-κB), inflammatory markers (TNFα, IL-1ß, and IL-6), and apoptotic markers (Bax, Bcl-2, and caspase 3) were evaluated. We showed that LPS challenge markedly increased the levels of serum alanine aminotransferase (ALT)/aspartate aminotransferase (AST) and other liver pathological changes in WT mice. In addition, LPS challenge elevated the levels of liver carbonyl proteins and serum inflammatory cytokines, upregulated the expression of TLR4, MyD88, and phosphorylated NF-κB in liver tissues. Moreover, LPS challenge significantly increased hepatocyte apoptosis, caspase 3 activity, and Bax level while suppressing Bcl-2 expression in liver tissues. These pathological changes were greatly attenuated in TLR4-/- mice. Similar pathological responses were provoked in primary hepatic Kupffer cells isolated from WT and TLR4-/- mice following LPS (1 µg/mL, 6 h) challenge. In summary, these results demonstrate that silencing of TLR4 attenuates LPS-induced liver injury through inhibition of inflammation and apoptosis via TLR4/MyD88/NF-κB signaling pathway. TLR4 deletion confers hepatoprotection against ALI induced by LPS, possibly by repressing macrophage inflammation and apoptosis.


Asunto(s)
Apoptosis/fisiología , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Inflamación/metabolismo , Receptor Toll-Like 4/metabolismo , Animales , Caspasa 3/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Citocinas/metabolismo , Técnicas de Inactivación de Genes , Hepatocitos/metabolismo , Macrófagos del Hígado/metabolismo , Lipopolisacáridos , Hígado/patología , Ratones Endogámicos C57BL , Ratones Noqueados , Factor 88 de Diferenciación Mieloide/metabolismo , Subunidad p50 de NF-kappa B/metabolismo , Transducción de Señal/fisiología , Receptor Toll-Like 4/genética
6.
World J Clin Cases ; 7(24): 4355-4365, 2019 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-31911919

RESUMEN

BACKGROUND: Multisystemic smooth muscle dysfunction syndrome (MSMDS) is a rare genetic disease worldwide. The main mutation is the actin alpha 2 (ACTA2) gene p.R179H. In this paper, we report a Chinese MSMDS patient and systematically review the previous literature. CASE SUMMARY: Here, we report a 9.6-month-old Chinese girl who was diagnosed with MSMDS based on her history and symptoms, such as recurrent cough, wheezing, and complications with congenital fixed dilated pupils. Chest high-resolution computed tomography revealed inhomogeneous lung transparency, obvious exudative lesions, and some lung fissures that were markedly thickened. Cranial magnetic resonance imaging excluded bleeding and infarction but showed abnormal signals in the centrum ovale majus and bilateral periventricular regions. Echocardiography only showed patent foramen ovale, and no patent ductus arteriosus, pulmonary artery dilatation, or pulmonary hypertension was found. Bronchoscopy indicated moderate bronchial malacia. These examinations in conjunction with the typical eye abnormality suggested a diagnosis of MSMDS, and sequencing of exon 6 of the ACTA2 gene demonstrated the heterozygous mutation c.536G>A, p.R179H. However, her parents' gene analyses were normal. CONCLUSION: MSMDS is a rare genetic disease mainly caused by the mutation of the ACTA2 gene p.R179H. Early genetic diagnosis should be performed for children presenting with congenital fixed dilated pupils and patent ductus arteriosus. During the process of diagnosis and treatment, clinicians should be on high alert for cerebrovascular, cardiovascular, and pulmonary complications.

7.
Biochem Biophys Res Commun ; 465(3): 324-30, 2015 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-26241674

RESUMEN

Proliferative vitreoretinopathy (PVR) is a serious complication of retinal detachment and vitreoretinal surgery, which can lead to severe vision reduction. Long non-coding RNAs (lncRNAs) play critical roles in many biological processes and disease development. We attempted to determine the role of lncRNAs in the setting of PVR. Microarray analysis revealed that 78 lncRNAs were abnormally expressed in the epiretinal membranes (ERMs) of PVR patients, including 48 up-regulated and 30 down-regulated lncRNA transcripts. We subsequently focus on one lncRNA, MALAT1, and investigated its expression pattern in the biofluid of PVR patients. MALAT1 was significantly up-regulated in the cellular and plasma fraction of peripheral blood in PVR patients. MALAT1 expression was obviously reduced after PVR operation. In vitro experiments revealed the role of MALAT1 in regulating RPE proliferation and migration, which is critical for ERMs formation. This study suggests that lncRNAs are the potential regulators of PVR pathology. MALAT1 is a potential prognostic indicator and a target for the diagnosis and gene therapy for PVR diseases.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , ARN Largo no Codificante/sangre , ARN Largo no Codificante/genética , Vitreorretinopatía Proliferativa/sangre , Vitreorretinopatía Proliferativa/genética , Secuencia de Bases , Biomarcadores de Tumor/sangre , Movimiento Celular/genética , Proliferación Celular/genética , Marcadores Genéticos/genética , Humanos , Datos de Secuencia Molecular , Vitreorretinopatía Proliferativa/patología
8.
Zhongguo Gu Shang ; 26(4): 349-53, 2013 Apr.
Artículo en Chino | MEDLINE | ID: mdl-23844502

RESUMEN

Osteoclasts and osteoblasts are not exist alone,while communicating with each other through direct contact, diffusible paracrine factors and cell-bone matrix interaction. Co-culture system of osteoblast with osteoclast,including direct co-culture and indirect co-culture. It should be according to the ratio of osteoclasts and osteoblasts under the pathology, choosing the same species. Compared with lonely culture of osteoblasts or osteoclasts,co-culture system is much closer to the microenvironment in vivo. It benefits to explain the interactions between osteoblasts and osteoclasts, exploring molecular communication in bone diseases. It was mainly used to investigate the pharmacological mechanism of herbal and western medicine in bone remodeling. Some osteoporosis drugs (such as epimedium,sanchi, fructus psoraleae, ranelate strontium) not only promoted osteoblastic bone formation, but also inhibited osteoclastic bone resorption in the system,so as to balance bone homeostasis. At the same time,it has been used to study medical physics and assess biomedical materials in recent years. Considerably,the co-cultrue system will be used to study the subchondral bone remodeling and its pharmacological mechanism of herbal and western medicine in osteoarthritis.


Asunto(s)
Técnicas de Cocultivo , Animales , Remodelación Ósea , Comunicación Celular , Humanos , Osteoblastos/citología , Osteoclastos/citología
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