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1.
Front Cardiovasc Med ; 8: 734400, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34881299

RESUMO

Background: Positive associations between inflammatory biomarkers and the risk of heart failure (HF) have been reported in conventional observational studies. However, the causal effects of inflammatory biomarkers on HF have not been fully elucidated. We conducted a Mendelian randomization (MR) study to examine the possible etiological roles of inflammatory biomarkers in HF. Methods: Summary statistical data for the associations between single nucleotide polymorphisms (SNPs) and C-reactive protein (CRP), fibrinogen, and components of the interleukin-1 (IL-1)-interleukin-6 (IL-6) inflammatory signaling pathway, namely, interleukin-1ß (IL-1ß), IL-1 receptor antagonist (IL-1ra), IL-6, and soluble IL-6 receptor (sIL-6r), were obtained from genome-wide association studies (GWASs) for individuals of European descent. The GWAS dataset of 977,323 participants of European ancestry, which included 47,309 HF cases and 930,014 controls, was collected to identify genetic variants underlying HF. A two-sample Mendelian randomization framework was implemented to examine the causality of the association between these inflammatory biomarkers and HF. Results: Our MR analyses found that genetically determined CRP and fibrinogen were not causally associated with HF risk (odds ratio [OR] = 0.93, 95% confidence interval [CI] = 0.84-1.02, p = 0.15; OR = 0.94, 95% CI = 0.55-1.58, p = 0.80, respectively). These findings remained consistent using different Mendelian randomization methods and in sensitivity analyses. For the IL-1-IL-6 pathway, causal estimates for IL-6 (OR = 0.86, 95% CI 0.81-0.91, p < 0.001), but not for IL-1ß, IL-1ra, or sIL-6r, were significant. However, the association between genetically determined IL-6 and HF risk became non-significant after excluding SNPs with potential pleiotropy (OR = 0.89, 95% CI = 0.77-1.03, p = 0.12). Conclusion: Our study did not identify convincing evidence to support that CRP and fibrinogen, together with their upstream IL-1-IL-6 signaling pathway, were causally associated with HF risk.

2.
Artigo em Inglês | MEDLINE | ID: mdl-34791775

RESUMO

Microbial infections has become a great threat to human health and one of the main risks arises from direct contact with the surfaces contaminated by pathogenic microbes. Developing long-lasting antimicrobial materials becomes an urgent need. Herein, a kind of hexagonal column interpenetrated spheres (HCISs) are fabricated by non-covalent assembly of plant gallic acid with quaternary ammonium surfactants. Different from one-time burst release of conventional antimicrobial agents, the HCIS acts like a "antimicrobial molecular bank" and releases the antimicrobial ingredients in a multistage way, leading to long-lasting antimicrobial performance. Taking advantage of strong hydrophobicity and adhesion, HCISs are applicable to various substrates and endowed with anti-water washing property, thus showing high in vitro antimicrobial efficiency ( > 99 %) even after being used for 10 cycles. Meanwhile, HCISs exhibit broad-spectrum antimicrobial activity against bacteria and fungi, and have good biocompatibility with mammalian cells. Such a low-cost and portable long-lasting antimicrobial agent meets the growing anti-infection demand in public spaces.

3.
FASEB J ; 35(11): e21990, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34665898

RESUMO

Eukaryotic initiation factor 2A (eIF2A) is a 65 kDa protein that functions in minor initiation pathways, which affect the translation of only a subset of messenger ribonucleic acid (mRNAs), such as internal ribosome entry site (IRES)-containing mRNAs and/or mRNAs harboring upstream near cognate/non-AUG start codons. These non-canonical initiation events are important for regulation of protein synthesis during cellular development and/or the integrated stress response. Selective eIF2A knockdown in cellular systems significantly inhibits translation of such mRNAs, which rely on alternative initiation mechanisms for their translation. However, there exists a gap in our understanding of how eIF2A functions in mammalian systems in vivo (on the organismal level) and ex vivo (in cells). Here, using an eIF2A-knockout (KO) mouse model, we present evidence implicating eIF2A in the biology of aging, metabolic syndrome and central tolerance. We discovered that eIF2A-KO mice have reduced life span and that eIF2A plays an important role in maintenance of lipid homeostasis, the control of glucose tolerance, insulin resistance and also reduces the abundance of B lymphocytes and dendritic cells in the thymic medulla of mice. We also show the eIF2A KO affects male and female mice differently, suggesting that eIF2A may affect sex-specific pathways. Interestingly, our experiments involving pharmacological induction of endoplasmic reticulum (ER) stress with tunicamycin did not reveal any substantial difference between the response to ER stress in eIF2A-KO and wild-type mice. The identification of eIF2A function in the development of metabolic syndrome bears promise for the further identification of specific eIF2A targets responsible for these changes.


Assuntos
Metabolismo dos Lipídeos , Longevidade , Síndrome Metabólica/metabolismo , /fisiologia , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fatores Sexuais
4.
Mol Cell ; 81(20): 4191-4208.e8, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34686314

RESUMO

To survive, mammalian cells must adapt to environmental challenges. While the cellular response to mild stress has been widely studied, how cells respond to severe stress remains unclear. We show here that under severe hyperosmotic stress, cells enter a transient hibernation-like state in anticipation of recovery. We demonstrate this adaptive pausing response (APR) is a coordinated cellular response that limits ATP supply and consumption through mitochondrial fragmentation and widespread pausing of mRNA translation. This pausing is accomplished by ribosome stalling at translation initiation codons, which keeps mRNAs poised to resume translation upon recovery. We further show that recovery from severe stress involves ISR (integrated stress response) signaling that permits cell cycle progression, resumption of growth, and reversal of mitochondria fragmentation. Our findings indicate that cells can respond to severe stress via a hibernation-like mechanism that preserves vital elements of cellular function under harsh environmental conditions.

5.
Nat Commun ; 12(1): 5264, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34489439

RESUMO

All-polymer solar cells (all-PSCs) based on polymerized small molecular acceptors (PSMAs) have made significant progress recently. Here, we synthesize two A-DA'D-A small molecule acceptor based PSMAs of PS-Se with benzo[c][1,2,5]thiadiazole A'-core and PN-Se with benzotriazole A'-core, for the studies of the effect of molecular structure on the photovoltaic performance of the PSMAs. The two PSMAs possess broad absorption with PN-Se showing more red-shifted absorption than PS-Se and suitable electronic energy levels for the application as polymer acceptors in the all-PSCs with PBDB-T as polymer donor. Cryogenic transmission electron microscopy visualizes the aggregation behavior of the PBDB-T donor and the PSMA in their solutions. In addition, a bicontinuous-interpenetrating network in the PBDB-T:PN-Se blend film with aggregation size of 10~20 nm is clearly observed by the photoinduced force microscopy. The desirable morphology of the PBDB-T:PN-Se active layer leads its all-PSC showing higher power conversion efficiency of 16.16%.

6.
Ann Transl Med ; 9(11): 935, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34350250

RESUMO

Background: Coronary artery disease, fatty liver disease, cardiac abnormalities, the metabolic syndrome, and insulin resistance may all occur in association with an increase of epicardial adipose tissue volume (EATV). Previous studies have shown that some cardiovascular-risk factors and healthy behaviors were related to a lower risk of EATV increase. The main purpose of this study was to determine whether ideal cardiovascular health (CVH) metrics were correlated with the prevalence of high EATV. Methods: The study commenced across 2013 and 2014 and involved volunteers from the Jidong (East Hebei) district. A cohort of 2,482 participants aged 45 years or older were randomly selected, of which 49.9% were women and none were diagnosed as having cancer, stroke, or heart diseases such as atrial fibrillation, heart failure, or myocardial infarction. The study collected information concerning seven CVH metrics; namely body mass index, dietary intake, smoking, blood pressure, physical activity, total cholesterol, and fasting blood glucose, and evaluated EATV based on computed tomography. Finally, an analysis of the relationship between ideal CVH metrics and the prevalence of high EATV was made applying multiple logistic regression. Results: On the basis that age, gender, and other potential confounding factors are adjusted, comparing the participants having an ideal CVH index of 2, 3, 4, 5 and 6-7 with those having a 0-1 metric, the adjusted odds ratios (95% confidence interval) of high EATV were as follows: 0.893 (0.468-1.705), 0.581 (0.316-1.069), 0.368 (0.202-0.670), 0.218 (0.119-0.400), and 0.161 (0.085-0.306) (P trend less than 0.0001). Similar negative correlations were also seen in other cases of different age groups and gender groups, where all P trends were less than 0.0001. Conclusions: The number of ideal CVH metrics in the northern Chinese population is negatively correlated with the prevalence of high EATV, supporting the greater use of EATV as a useful parameter in clinical practice.

7.
J Pediatr ; 238: 233-240.e1, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34228986

RESUMO

OBJECTIVE: To analyze the aerobic fitness and evolution of exercise tolerance in patients with single-ventricle physiology after total cavopulmonary connection (TCPC) with an extracardiac conduit (ECC). STUDY DESIGN: This retrospective cohort study included patients with previous ECC-TCPC who underwent cardiopulmonary exercise testing (CPET) between September 2010 and September 2019. Patients who completed at least 2 tests (≥6 months apart) with adequate levels of effort were recruited for the serial CPET evaluation. RESULTS: We identified 70 patients (50% male) with a mean age of 6.45 ± 5.14 years at ECC-TCPC and 15.67 ± 5.03 years at the initial CPET. The peak oxygen consumption (peak VO2) to predicted value (peak PD) was 55.90 ± 16.81%. Twenty of the 70 identified patients (50% male) were recruited for serial analysis. The average number of CPETs was 2.6 per patient. The average duration from the first CPET to the last CPET was 3.64 years. The peak VO2 and PD increased slowly, with mean rates of 38.77 ± 129.01 mL/min and 1.66 ± 6.40%, respectively, during the study period. CONCLUSIONS: Although the patients had lower exercise tolerance after ECC-TCPC compared with their normal peers, exercise tolerance appears to have been preserved over the adolescent period in those who underwent serial testing after ECC-TCPC.


Assuntos
Limiar Anaeróbio/fisiologia , Teste de Esforço/métodos , Técnica de Fontan/efeitos adversos , Adolescente , Criança , Pré-Escolar , Feminino , Cardiopatias Congênitas/cirurgia , Humanos , Lactente , Masculino , Estudos Retrospectivos , Taiwan
8.
Nat Commun ; 12(1): 4616, 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34326339

RESUMO

Conventional ultrafine-grains can generate high strength in Mg alloys, but significant tradeoff of corrosion resistance due to inclusion of a large number of non-equilibrium grain boundaries. Herein, an ultrafine-grain structure consisting of dense ultrafine twins is prepared, yielding a high strength up to 469 MPa and decreasing the corrosion rate by one order of magnitude. Generally, the formation of dense ultrafine twins in Mg alloys is rather difficult, but a carefully designed multi-directional compression treatment effectively stimulates twinning nucleation within twins and refines grain size down to 300 nm after 12-passes compressions. Grain-refinement by low-energy twins not only circumvents the detrimental effects of non-equilibrium grain boundaries on corrosion resistance, but also alters both the morphology and distribution of precipitates. Consequently, micro-galvanic corrosion tendency decreases, and severe localized corrosion is suppressed completely. This technique has a high commercial viability as it can be readily implemented in industrial production.

10.
Front Pediatr ; 9: 657551, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34123966

RESUMO

Objective: Studies among Western children have observed that the peak oxygen consumption (peak V ˙ O2) of boys is higher than that of girls, and this difference increases as children progress through adolescence. However, the maturation process and social expectation toward Eastern boys and girls are much different from their Western counterparts. This study aimed to provide baseline information on cardiopulmonary fitness (CRF) of Taiwanese children and adolescents in relation to age and sex. We also evaluated the correlation between body mass and CRF and compared the CRF between non-obese and overweight/obese children. Methods: We conducted a retrospective study of children and adolescents aged 4-18 years in Taiwan. Participants were classified into four groups based on age (group 1, aged 4-6; group 2, aged 7-9; group 3, aged 10-13; and group 4, aged 14-18 years). All participants completed symptom-limited exercise test by treadmill and anthropometric measurements through bioelectrical impedance method. Results: In total, 897 (448 men, 449 women) participants were analyzed. Boys had higher peak V ˙ O2 (all p < 0.01) and peak metabolic equivalent (MET, all p < 0.05) than girls in all the four groups. Age significantly (P < 0.001) correlated with peak V ˙ O2 in all participants, boys, and girls, with coefficients of determination (R 2) of 0.9349, 0.9433, and 0.9085, respectively. The peak V ˙ O2 (all p < 0.001) of all the groups and peak MET (all p < 0.05) of group 2-4 associated with BMI and FMI modestly to moderately. Non-obese children had higher peak MET in group 1 (p = 0.049) and group 2-4 (all p < 0.001) than overweight/obese children significantly. Conclusions: The difference in peak V ˙ O2 and anthropometry-body composition between sexes was observed earlier in children in Taiwan than those in Western countries. Non-obese children had better CRF than overweight/obese children and the difference presented since preschool age.

11.
Nat Commun ; 12(1): 3477, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34108449

RESUMO

In a narrow temperature window in going from the isotropic to highly chiral orders, cholesteric liquid crystals exhibit so-called blue phases, consisting of different morphologies of long, space-filling double twisted cylinders. Those of cubic spatial symmetry have attracted considerable attention in recent years as templates for soft photonic materials. The latter often requires the creation of monodomains of predefined orientation and size, but their engineering is complicated by a lack of comprehensive understanding of how blue phases nucleate and transform into each other at a submicrometer length scale. In this work, we accomplish this by intercepting nucleation processes at intermediate stages with fast cross-linking of a stabilizing polymer matrix. We reveal using transmission electron microscopy, synchrotron small-angle X-ray diffraction, and angle-resolved microspectroscopy that the grid of double-twisted cylinders undergoes highly coordinated, diffusionless transformations. In light of our findings, the implementation of several applications is discussed, such as temperature-switchable QR codes, micro-area lasing, and fabrication of blue phase liquid crystals with large domain sizes.

12.
Nutr Metab Cardiovasc Dis ; 31(9): 2547-2556, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34172321

RESUMO

AIMS: Epicardial adipose tissue has been reported to be associated with the development of cardiometabolic disease. Whether this is true for hypertension and non-dipper blood pressure remains controversial. Here, we conducted a systemic review and meta-analysis to evaluate the association between EAT and blood pressure. DATA SYNTHESIS: Pubmed, Embase, and Web of Science were searched for relevant papers. Studies reported on the difference of EAT thickness between hypertensive and normotensive patients, or those recorded odds ratio (OR) between EAT and hypertension were included. The standard mean difference (SMD) and ORs were extracted and pooled using a random-effects model respectively. We further assessed the effect of EAT on circadian rhythm of blood pressure by combining multiple-adjusted ORs for non-dipper blood pressure. Seven studies with an overall sample of 1089 patients reported the mean difference of EAT thickness between hypertensive and normotensive patients, and the hypertensive patients had higher EAT (SMD = 1.07; 95% CI: 0.66-1.48; I2 = 89.2%) compared with controls. However, the pooled association between EAT and hypertension from two studies was not significant (OR = 1.65, 95%CI 0.62-4.68; I2 = 87.5%). The summary risk effect of EAT on non-dipper blood pressure from six studies comprising1208 patients showed that each 1 mm increment of EAT was associated with a 2.55-fold risk of non-dipper blood pressure. CONCLUSION: Hypertensive patients tend to present higher EAT thickness near the right ventricular wall and increased EAT thickness might be associated with high risk of non-dipper blood pressure. Future researches are warranted to determine the causal link between EAT and hypertension and the underlying mechanism.


Assuntos
Tecido Adiposo/fisiopatologia , Adiposidade , Pressão Sanguínea , Hipertensão/fisiopatologia , Tecido Adiposo/diagnóstico por imagem , Feminino , Humanos , Hipertensão/diagnóstico , Masculino , Pericárdio , Prognóstico , Medição de Risco , Fatores de Risco
13.
J Am Chem Soc ; 143(15): 5717-5726, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33843219

RESUMO

Li+-conductive ceramic oxide electrolytes, such as garnet-structured Li7La3Zr2O12, have been considered as promising candidates for realizing the next-generation solid-state Li-metal batteries with high energy density. Practically, the ceramic pellets sintered at elevated temperatures are often provided with high stiffness yet low fracture toughness, making them too brittle for the manufacture of thin-film electrolytes and strain-involved operation of solid-state batteries. The ceramic powder, though provided with ductility, does not yield satisfactorily high Li+ conductivity due to poor ion conduction at the boundaries of ceramic particles. Here we show, with solid-state nuclear magnetic resonance, that a uniform conjugated polymer nanocoating formed on the surface of ceramic oxide particles builds pathways for Li+ conduction between adjacent particles in the unsintered ceramics. A tape-casted thin-film electrolyte (thickness: <10 µm), prepared from the polymer-coated ceramic particles, exhibits sufficient ionic conductivity, a high Li+ transference number, and a broad electrochemical window to enable stable cycling of symmetric Li/Li cells and all-solid-state rechargeable Li-metal cells.

14.
PLoS One ; 16(4): e0250491, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33901243

RESUMO

As the most common type of neurodegenerative diseases (NDDs), Alzheimer's disease (AD) is thought to be caused mainly by the excessive aggregation of ß-amyloid protein (Aß). However, a growing number of studies have found that reactive oxygen species (ROS) play a key role in the onset and progression of AD. The present study aimed to probe the neuroprotective effect of high-frequency low-intensity pulsed electric field (H-LIPEF) for SH-SY5Y cells against hydrogen peroxide (H2O2) and Aß-induced cytotoxicity. By looking in a systematic way into the frequency- and amplitude-dependent neuroprotective effect of pulsed electric field (PEF), the study finds that H-LIPEF at 200 Hz produces the optimal protective effect for SH-SY5Y cells. The underlying mechanisms were confirmed to be due to the activation of extracellular signal-regulated kinase (ERK) pathway and the downstream prosurvival and antioxidant proteins. Because the electric field can be modified to focus on specific area in a non-contact manner, the study suggests that H-LIPEF holds great potential for treating NDDs, whose effect can be further augmented with the administering of drugs or natural compounds at the same time.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Eletricidade , Peróxido de Hidrogênio/toxicidade , Sistema de Sinalização das MAP Quinases , Neuroproteção , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Flavonoides/farmacologia , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Neuroproteção/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Coloração e Rotulagem , Quinases Associadas a rho/metabolismo
15.
Nat Commun ; 12(1): 1293, 2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33637721

RESUMO

Tendon injuries disrupt the balance between stability and mobility, causing compromised functions and disabilities. The regeneration of mature, functional tendons remains a clinical challenge. Here, we perform transcriptional profiling of tendon developmental processes to show that the extracellular matrix-associated protein periostin (Postn) contributes to the maintenance of tendon stem/progenitor cell (TSPC) functions and promotes tendon regeneration. We show that recombinant periostin (rPOSTN) promotes the proliferation and stemness of TSPCs, and maintains the tenogenic potentials of TSPCs in vitro. We also find that rPOSTN protects TSPCs against functional impairment during long-term passage in vitro. For in vivo tendon formation, we construct a biomimetic parallel-aligned collagen scaffold to facilitate TSPC tenogenesis. Using a rat full-cut Achilles tendon defect model, we demonstrate that scaffolds loaded with rPOSTN promote endogenous TSPC recruitment, tendon regeneration and repair with native-like hierarchically organized collagen fibers. Moreover, newly regenerated tendons show recovery of mechanical properties and locomotion functions.


Assuntos
Biomimética/métodos , Moléculas de Adesão Celular/genética , Regeneração , Tecidos Suporte , Tendão do Calcâneo , Animais , Engenharia Biomédica/métodos , Moléculas de Adesão Celular/metabolismo , Diferenciação Celular , Movimento Celular , Proliferação de Células , Colágeno , Perfilação da Expressão Gênica , Masculino , Ratos , Ratos Sprague-Dawley , Regeneração/genética , Células-Tronco/metabolismo , Traumatismos dos Tendões/terapia
16.
J Aging Phys Act ; 29(5): 866-877, 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33596540

RESUMO

Because of a shortage of health care providers, providing rehabilitation in health care facilities is difficult. Virtual reality-based rehabilitation is effective in older populations. There are only a few studies among patients with sarcopenia. This is a quasi-experimental, single-group, pretest-posttest design evaluating the clinical effectiveness of virtual reality-based progressive resistance training among residents aged over 60 years with sarcopenia in rural care facilities. The authors used Oculus Rift with headsets to provide the virtual reality-based progressive resistance training. The authors administered the program twice per week, 30 min per session, for 12 weeks. The primary outcomes were dominant handgrip strength, walking speed, and appendicular skeletal muscle mass index. Data from 30 participants were analyzed. Significant improvements in handgrip strength and walking speed were observed. Although an increasing trend in appendicular skeletal muscle mass index was observed, it did not reach statistical significance. The authors concluded that the virtual reality-based progressive resistance training is partially effective in older sarcopenic adults in health care facilities.

17.
FEBS J ; 288(22): 6365-6391, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33387379

RESUMO

Inflammation is a pathological hallmark associated with bacterial and viral infections, autoimmune diseases, genetic disorders, obesity and diabetes, as well as environmental stresses including physical and chemical trauma. Among numerous proteins regulating proinflammatory signaling, very few such as Protein kinase R (PKR), have been shown to play an all-pervading role in inflammation induced by varied stimuli. PKR was initially characterized as an interferon-inducible gene activated by viral double-stranded RNA with a role in protein translation inhibition. However, it has become increasingly clear that PKR is involved in multiple pathways that promote inflammation in response to stress activation, both dependent on and independent of its cellular protein activator of PKR (PACT). In this review, we discuss the signaling pathways that contribute to the initiation of inflammation, including Toll-like receptor, interferon, and RIG-I-like receptor signaling, as well as inflammasome activation. We go on to discuss the specific roles that PKR and PACT play in such proinflammatory signaling, as well as in metabolic syndrome- and environmental stress-induced inflammation.


Assuntos
Inflamação/metabolismo , Proteínas de Ligação a RNA/metabolismo , eIF-2 Quinase/metabolismo , Humanos , Transdução de Sinais
18.
Sci Total Environ ; 765: 142694, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33071117

RESUMO

The environment of the Bohai Sea is under enormous pressure because of rapid economic and urban development associated with increased population inhabiting the coastal zone. Environmental threats to the coastal ecosystem were analyzed using 2006-2017 statistical/monitoring data from the State Oceanic Administration, China. The results showed that harmful algal blooms occurred a total of 104 times during the period of 2006-2017, for a cumulative area of more than 21,275 km2. The main environmental threats came from offshore oil and gas production in the form of hydrocarbon pollution during extraction, as well as from urban wastewater and sewage. Oil pollution, mainly generated from spills, offshore oil platforms and large number of vessels/ports, was found to cause very severe negative impacts on the environment. Another threat is from excessive groundwater exploitation which has resulted in seawater intrusion and soil salinization occurrence in more than 90% of coastal areas around the Bohai Sea. The maximum distance of intrusion by seawater and soil salinization was more than 40 and 32 km inland, respectively. Contamination by terrestrial pollutants was identified as another threat affecting the environment quality of the Bohai Sea. Approximately 840,000 t of pollutants were carried into the sea by major rivers annually for 2010-2017. The standard discharge rate of terrestrial-source sewage outlets did not exceed 50%; however, only 13.12% of sea areas adjacent to sewage outlets (rivers) met the environmental quality requirements for functional marine areas. The results also showed the frequency of storm surges in the Bohai Sea which was 8.83 times per year and the resulting annual direct economic losses reached (RMB) 1.77 billion for 2006-2017. The results highlight the urgent need to implement an ecological management strategy to reduce the heavy ecological burdens in the coastal zone of the Bohai Sea.

19.
Sci Total Environ ; 765: 142691, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33071119

RESUMO

Inland pollutants input is a key impact factor for the coastal water quality of the Bohai Sea. The coastal and inland water pollutant inputs were analyzed by using monitoring data of recent years from the State Oceanic Administration. The results showed that more than 56% of the Bohai Sea area was unclean seawater in 2012, although the water quality improved gradually after that time. In 2017, about one-third of the Bohai Sea area still had unclean seawater. Inorganic nitrogen, reactive phosphate, and petroleum hydrocarbons are the main pollutants in the seawater. A total of approximately 840,000 t of pollutants was transported to the sea each year by major rivers during 2010-2017. Significant correlations (p < 0.05) were found between the third-grade level seawater area and the pollutants of CODcr, petroleum, NO3--N, NH4+-N, NO2--N, Cu, and Pb and between the inferior fourth-grade level seawater area and the pollutants of petroleum, NO2--N, Pb, and NO3--N. The standard discharge rate of terrestrial-source sewage outlets was no more than 50%. The low standard discharge rate of the major terrestrial-source sewage pollutants of CODcr, NH4+-N, TP, BOD5, and SS caused more than 80% of the monitored sea areas adjacent to the selected key sewage outlets to not meet the water quality requirements of the marine functional area. The results suggest that implementing a coastal water management plan is necessary to reduce the heavy ecological burdens on the coastal zone of the Bohai Sea.

20.
Sci Total Environ ; 757: 143825, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33280872

RESUMO

Due to the enhancement of human activities on the global scale, the total amount of atmospheric nitrogen (N) deposition and the rate keep increasing, which seriously affect the structure and function of terrestrial ecosystems. In order to study the effects of N deposition on the soil structure and function of coastal saline wetlands, we established a long-term nitrogen deposition simulation platform in 2012 in the Yellow River delta (YRD). Herein, we analyzed the composition and diversity of the soil microbial community under different N deposition treatments (LNN, MNN and HNN, which stand for 50 kg N ha-1 yr-1, 100 kg N ha-1 yr-1, and 200 kg N ha-1 yr-1) and in a water-only control (CK). The results showed that with the increasing level of N deposition, α-diversity (Shannon and Simpson indices) decreased significantly, and the composition of the microbial community changed. At the phylum level, compared with CK, the relative abundance of Chloroflexi increased significantly under the treatment of HNN (P = 0.002), but the relative abundance of Chlorobi (P = 0.013) and Verrucomicrobia (P = 0.035) decreased significantly. At the genus level, compared with CK, the relative abundance of Bacillus (P = 0.01) and Halomonas (P = 0.042) increased significantly with HNN treatment. Bacillus and Nitrococcus showed a significant correlation with soil NH4+-N. The results suggest that the response of microorganisms to N deposition treatments varied by the concentration, and the deposition of a high concentration would increase the nutrients in the soil, but reduce the diversity of soil microorganisms, causing a negative impact on the coastal wetland ecosystem of the YRD.


Assuntos
Microbiota , Áreas Alagadas , China , Humanos , Nitrogênio/análise , Rios , Solo , Microbiologia do Solo
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