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1.
Zhonghua Liu Xing Bing Xue Za Zhi ; 44(8): 1237-1244, 2023 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-37661615

RESUMO

Objective: Analysis of the characteristics of influenza epidemic in Anhui Province and quantification of the impact of different factors on influenza occurrence, providing scientific basis for better influenza prevention and control. Methods: Descriptive analysis and factor analysis were conducted on influenza-like illness (ILI) cases and RT-PCR results in Anhui Province from 2013 to 2021 using data from China's Influenza Monitoring Information System. Results: The percentage of influenza-like illness (ILI%) of sentinel hospitals in Anhui Province from April 1, 2013 to March 31, 2021 was 3.80% (1 209 142/31 779 987), showing an overall increasing trend, with a relatively high proportion in 2017-2018 at 4.30% (191 148/4 448 211). The proportion of ILI cases in infants and young children aged 0-4 years was a relatively high at 54.14% (654 676/1 209 142), and the highest ILI% was observed in Fuyang City, Anhui Province (6.25%, 236 863/3 788 863). Laboratory monitoring results showed that the positive rate of ILI cases in sentinel hospitals in 8 influenza monitoring years was 16.38% (34 868/212 912), showing an increasing trend year by year, with a relatively proportion in 2017-2018 at 26.19% (6 936/26 488). The detection rate of school-age children aged 5-14 years was a relativelyhigh at 28.81% (13 869/48 144), and the positive rate was a relatively high in Wuhu City among the 16 cities, reaching 22.01% (2 693/122 237). Influenza activity showed a single peak in winter-spring and alternating double peaks in winter-spring and summer, with different subtypes alternating, and A (H3N2) was the dominant subtype in summer. The results of a multiple logistic regression model showed that the positive rate was higher in 2017-2018, among children aged 5-14 years, in winter, and in southern Anhui. Conclusions: Influenza epidemic in Anhui Province has a clear seasonal pattern, and the ILI% and detection rate have shown an upward trend from 2013 to 2021. Therefore, it is suggested to ensure vaccine supply before the winter-spring influenza season arrives, and to strengthen vaccine uptake and health education to avoid the risk of infection during the peak period of influenza.


Assuntos
Vacinas contra Influenza , Influenza Humana , Criança , Lactente , Humanos , Pré-Escolar , Influenza Humana/epidemiologia , Vírus da Influenza A Subtipo H3N2 , Cidades , Fatores de Risco
2.
Zhonghua Nei Ke Za Zhi ; 62(9): 1085-1092, 2023 Sep 01.
Artigo em Chinês | MEDLINE | ID: mdl-37650182

RESUMO

Objective: To evaluate the diagnostic for classification of newly diagnosed diabetes patients and assess the application of the screening tests recommended by the 2022 Chinese Expert Consensus on Diabetes Classification. Methods: Retrospective case series study. The data from the electronic medical record system of patients with new-onset diabetes mellitus (within 1 year of disease onset) who attending the Diabetes Specialist Outpatient Clinic at the Second Xiangya Hospital of Central South University from January 1, 2018 to December 31, 2021 were collected for the analysis. Based on the consensus, patients were categorized according their age of onset, body mass index (BMI), and suspicion of type 1 diabetes mellitus (T1DM). The chi-square statistic was used to compare key classifier indicators, including C-peptide, islet autoantibodies, and genetic markers, in the subgroups. The diagnosis in suspected T1DM patients was also evaluated. The screening strategy recommended in the consensus was further assessed using a logistic regression model and the area under the receiver-operating curve (AUC). Results: A total of 3 384 patients with new-onset diabetes were included. The average age of disease onset was (46.3±13.9) years, and 61.0% (2 065/3 384) of the patients were male. The proportions of patients who completed C-peptide and glutamic acid decarboxylase antibody (GADA) tests were 36.6% (1 238/3 384) and 37.5% (1 269/3 384), respectively. There were no significant differences in C-peptide test results among the subgroups (all P>0.05). In contrast, the GADA detection rate was higher in patients with young age of onset (<30 years old), in those who were non-obese (BMI<24 kg/m2), and in those clinically suspected of T1DM (all P<0.05). According to the diagnostic pathway proposed by the consensus, only 57.4% (1 941/3 384) of patients could be subtyped. For a definitive diagnosis, the remaining patients needed completion of C-peptide, islet autoantibody, genetic testing, or follow-up. Furthermore, among patients with clinical features of suspected T1DM, the antibody positivity rate was higher than in non-suspected T1DM patients [24.5% (154/628) vs. 7.1% (46/646), P<0.001]. When the clinical features of suspected T1DM defined in the consensus were taken as independent variables and antibody positivity was considered the outcome variable in the logistic regression model, young onset, non-obese onset, and ketosis onset could enter the model. Based on AUC analysis, the accuracy of the diagnostic model was 0.77 (95%CI 0.73-0.81), suggesting that the clinical features of suspected T1DM in the consensus have good clinical diagnostic value for this patient subgroup. Conclusions: There was a significant discrepancy between the clinical practice of diabetes classification and the process recommended by the consensus, which was specifically reflected in the low proportions of both subtyping indicator testing and definitively subtyped diabetes patients. Attention should be pay to the classification diagnosis process proposed in the consensus and the clinical detection rate of key diabetes subtyping indicators such as C-peptide and islet autoantibodies for diabetes classification should be improved. Noteworthy, the screening strategy for T1DM proposed by the consensus showed good clinical application value.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Feminino , Diabetes Mellitus Tipo 1/diagnóstico , Peptídeo C , Consenso , População do Leste Asiático , Estudos Retrospectivos , Autoanticorpos
3.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 57(9): 927-931, 2022 Sep 09.
Artigo em Chinês | MEDLINE | ID: mdl-36097939

RESUMO

Objective: To compare the accuracy and retention of denture bases fabricated by injection molding, milling, and three-dimensional (3D) printing fabricating, in order to provide some references for clinical practice. Methods: A maxillary edentulous jaw model made was used to duplicated 10 working casts. The casts were numbered and scanned. The wax pattern was designed by digital ways and conventional methods and then the denture bases were fabricated by injection molding, milling, and 3D printing. The tissue surface of experimental denture base was obtained using a dental laboratory scanner. The deviation between the tissue surface of the fabricated denture bases and the working model was evaluated. A digital force gauge was used to measure the traction force. Results: The milling group [(0.076±0.026) mm] was more accurate than the 3D printing group [(0.117±0.041) mm] (P<0.05) and the injection group [(0.120± 0.025) mm] (P<0.05). The accuracy of 3D printing group and that of injection group were not statistically significant (P>0.05). The milling group [(9.55±2.44) N] demonstrated greater retentive force than 3D printing group [(5.19±0.06) N] and injection molding group [(1.52±0.52) N] (P<0.05). Conclusions: The denture base fabricated by milling was more accurate and showed the greatest retentive force than the other groups. And 3D printing group showed better retentive force than the injection molding group. Both digital manufacturing methods can meet the requirements of clinical application.


Assuntos
Bases de Dentadura , Arcada Edêntula , Desenho Assistido por Computador , Humanos , Maxila , Impressão Tridimensional
4.
Zhonghua Gan Zang Bing Za Zhi ; 30(6): 667-671, 2022 Jun 20.
Artigo em Chinês | MEDLINE | ID: mdl-36038331

RESUMO

Most hepatocellular carcinoma are diagnosed at an advanced stage and thereby have a high mortality rate. Thus, the key to improving patient prognosis is early diagnosis of hepatocellular carcinoma. In recent years, Asian scholars have summarized a series of hepatocellular carcinoma risk score model for population with chronic hepatitis B, which can help to identify high-risk groups early and improve the early diagnosis rate. This paper briefly analyzes the risk factors and validated risk model for early prediction of hepatitis B virus-related hepatocellular carcinoma, and further reviews the effect of antiviral therapy on the risk of hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Hepatite B , Neoplasias Hepáticas , Antivirais/uso terapêutico , Carcinoma Hepatocelular/patologia , Diagnóstico Precoce , Hepatite B/tratamento farmacológico , Vírus da Hepatite B , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Humanos , Neoplasias Hepáticas/patologia , Fatores de Risco
5.
Hum Exp Toxicol ; 41: 9603271221097364, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35713481

RESUMO

INTRODUCTION: MiR-200c plays a central role in glucose metabolism in cancer cells. However, its upstream regulators in this process are unknown. CircRNA CSPP1 (circCSPP1) was predicted to bind to premature miR-200c, an oncogenic miRNA. Therefore, we explored their interaction in osteosarcoma (OS). METHODS: Differential circCSPP1 and miR-200c expression in OS was analyzed using RT-qPCR. Glucose metabolism was analyzed by glucose uptake assay. Subcellular circCSPP1 location in OS cells was detected using cellular fractionation assay. The direct interaction between circCSPP1 and miR-200c was explored using RNA-RNA pull-down assay. The role of circCSPP1 in miR-200c maturation was investigated by analyzing both mature and premature miR-200c levels in OS cells with circCSPP1 overexpression. RESULTS: CircCSPP1 and premature miR-200c levels were increased while mature miR-200c level was decreased in OS. CircCSPP1 was detected in both the nuclear and cytoplasm fractions of OS cells. CircCSPP1 directly interacted with premature miR-200c. CircCSPP1 overexpression increased premature miR-200c level, glucose uptake, and cell proliferation, but decreased mature miR-200c level. MiR-200c overexpression suppressed the role of circCSPP1 in OS cells. CONCLUSIONS: CircCSPP1 promotes OS cell proliferation and increases glucose metabolism by suppressing miR-200c maturation.


Assuntos
Neoplasias Ósseas , Proteínas de Ciclo Celular/genética , MicroRNAs/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Osteossarcoma , RNA Circular , Neoplasias Ósseas/genética , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Glucose , Humanos , MicroRNAs/genética , Osteossarcoma/genética , RNA Circular/genética
6.
Zhonghua Yi Shi Za Zhi ; 52(1): 12-20, 2022 Jan 28.
Artigo em Chinês | MEDLINE | ID: mdl-35570352

RESUMO

Tanksuqnameh (Yi Li Han) as the earliest Persian transcription of traditional Chinese medicine for the west, has great value in the history of Sino-Iranian medical cultural exchanges. The eleven drawings attached to Tanksuqnameh concerning meridians and pulse diagnosis were compared to relative paintings attached to some ancient Chinese medical books. It was found that eight of the drawings attached to Tanksuqnameh came from the paintings attached to The Zhuan Tu Ju Jie of the Yellow Emperor Eighty-One Nan Jing by Li Jiong. The sources of the three paintings have not been identified. However, based on the comparison between the three paintings attached to Tanksuqnameh and the paintings in the medical books in the Ming Dynasty in terms of outlines, names and the content, they might come from the same medical book as a reference.


Assuntos
Livros , Meridianos , China , Medicina Tradicional Chinesa
7.
J Dent Res ; 101(4): 448-457, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34796776

RESUMO

Periodontitis is a complex inflammatory disease affecting the supporting structures of teeth and is associated with systemic inflammatory disorders. Regulator of G-protein signaling 12 (RGS12), the largest protein in the RGS protein family, plays a crucial role in the development of inflammation and bone remodeling. However, the role and mechanism(s) by which RGS12 may regulate periodontitis have not been elucidated. Here, we showed that ablation of RGS12 in Mx1+ hematopoietic cells blocked bone loss in the ligature-induced periodontitis model, as evidenced morphometrically and by micro-computed tomography analysis of the alveolar bone. Moreover, hematopoietic cell-specific deletion of RGS12 inhibited osteoclast formation and activity as well as the production of inflammatory cytokines such as IL1ß, IL6, and TNFα in the diseased periodontal tissue. In the in vitro experiments, we found that the overexpression of RGS12 promoted the reprogramming of macrophages to the proinflammatory M1 type, but not the anti-inflammatory M2 type, and enhanced the ability of macrophages for migration. Conversely, knockdown of RGS12 in macrophages inhibited the production of inflammatory cytokines and migration of macrophages in response to lipopolysaccharide stimulation. Our results demonstrate for the first time that inhibition of RGS12 in macrophages is a promising therapeutic target for the treatment of periodontitis.


Assuntos
Periodontite , Proteínas RGS , Proteínas de Ligação ao GTP , Humanos , Ativação de Macrófagos , Osteogênese , Microtomografia por Raio-X
8.
Cell Tissue Res ; 388(1): 167-179, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34816281

RESUMO

In vertebrates, melatonin is mainly synthesized from serotonin in the pineal gland. Many reports have documented that melatonin is also synthesized in the extra-pineal tissues, but the synthesis of melatonin in the corpus luteum (CL) of pregnant sows has never been studied. The objectives of this study were to evaluate the expression of melatonin-synthesizing enzymes, arylalkylamine N-acetyltransferase (AANAT) and acetylserotonin O-methyltransferase (ASMT), in the CL of sows during pregnancy and to investigate the synthesis of melatonin in luteal cells. Results showed that AANAT and ASMT were both expressed in the CL of sows during pregnancy, higher levels were observed in the early- and mid-stage CL, and the lowest abundance was found in the regressing CL (later-stage). The immunostaining for AANAT and ASMT was predominantly localized in the large luteal cells of porcine CL during pregnancy. Furthermore, melatonin was synthesized in luteal cells from serotonin in a dose- and time-dependent manner. And the expressions of AANAT and ASMT were upregulated by serotonin in luteal cells. In addition, progesterone (P4) secretion and cell viability were promoted in luteal cells treated with serotonin, and the stimulatory effects were blocked by luzindole (a non-selective MT1 and MT2 antagonist). Finally, the expressions of MT1 and MT2 were augmented by serotonin in luteal cells. In conclusion, this study demonstrates for the first time the developmental expression of AANAT and ASMT in the CL and a local synthesis of melatonin in luteal cells of pregnant sows, and suggests a paracrine and/or autocrine role for melatonin in luteal function.


Assuntos
Células Lúteas , Melatonina , Acetilserotonina O-Metiltransferasa/metabolismo , Animais , Arilalquilamina N-Acetiltransferase/metabolismo , Corpo Lúteo , Feminino , Células Lúteas/metabolismo , Melatonina/farmacologia , Gravidez , Suínos
9.
Zhonghua Yi Shi Za Zhi ; 52(6): 335-342, 2022 Nov 28.
Artigo em Chinês | MEDLINE | ID: mdl-36624673

RESUMO

This paper introduced and summarized the ways and skills of promoting the circulation of air in the human body (Dao Yin Xing Qi) in Dao Yin Tu and Yin Shu and compared them with the way of breathing in Qu Gu Shi Qi. It was found that early Dao Yin drew on breathing thinking (Qi theory) and was meaningful for human health and helpful in examining how Qi theory was shaped and developed. It was also found that Dao Yin treated diseases based on meridian theories because Dao Yin for disease treatment in Dao Yin Tu and Yin Shu was related with the eleven meridians and their main symptoms in Mai Shu. The methods of practicing Dao Yin were likely to take references from the transmission routes of human meridians. The relationship between Dao Yin, Qi and meridians indicated that Qi and meridians were taken as the focus for people to understand the human body. Qi and meridians theories, widely accepted in ancient times, were taken as theoretical guidelines by stone needle, moxibustion and Dao Yin to maintain health and disease treatment.


Assuntos
Terapia por Acupuntura , Meridianos , Moxibustão , Humanos , Qi , Agulhas
10.
J Dent Res ; 100(5): 522-531, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33198557

RESUMO

Oral squamous cell carcinoma (OSCC) is the most common head and neck cancer characterized by aggressive local invasion and metastasis. The pathogenesis of OSCC is mainly due to the accumulation of genetic alterations in epithelial cells, but the underlying mechanism for its development remains unclear. Here, we found that the expression level of regulator of G protein signaling 12 (RGS12) was significantly reduced in human OSCC. To understand the role and mechanism of RGS12 in OSCC, we generated a novel RGS12 global knockout (CMVCre/+; RGS12fl/fl) mouse model by crossing RGS12fl/fl mice with CMV-Cre transgenic mice and then further induced the mice to develop OSCC by using 4-nitroquinoline 1-oxide (4NQO). Deletion of RGS12 exhibited aggressive OSCC in the tongue compared with the control RGS12fl/fl mice. Knockdown of RGS12 in OSCC cells significantly increased cell proliferation and migration. Mechanistically, we found that RGS12 associated with phosphatase and tension homolog (PTEN) via the PDZ domain to upregulate the phosphorylation and SUMOylation of PTEN and then correspondingly inactivated the AKT/mTOR signaling pathway. To test the potential therapeutic effect of RGS12 on OSCC, we overexpressed RGS12 in OSCC cells and found a significant inhibition of cancer cell proliferation and migration. Moreover, subcutaneous inoculation of RGS12-overexpressed OSCC cells in NOD scid mice showed a significant reduction in tumor formation. Our findings reveal that RGS12 is an essential tumor suppressor and highlights RGS12 as a potential therapeutic target and prognostic biomarker of OSCC.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , PTEN Fosfo-Hidrolase , Proteínas RGS , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Proteínas de Ligação ao GTP , Camundongos , Camundongos Knockout , Fosforilação , Proteínas RGS/genética , Proteínas RGS/metabolismo , Transdução de Sinais , Sumoilação
11.
Zhonghua Gan Zang Bing Za Zhi ; 28(6): 540-544, 2020 Jun 20.
Artigo em Chinês | MEDLINE | ID: mdl-32660189

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is a clinicopathological syndrome with similar hepatic histological changes to alcoholic liver disease, but without a history of excessive alcohol intake. Obesity, hyperlipidemia, diabetes, hypertension and other metabolic disorders are closely related to its occurrence and development, and its core mechanism is insulin resistance. In addition, there are also non-metabolic-related factors for the occurrence of non-alcoholic fatty liver disease, such as pancreatoduodenectomy. Pancreatoduodenectomy is the standard procedure for the treatment of tumor around the head of pancreas and ampulla. Postoperative pancreatic malfunction induced by pancreatic exocrine function after pancreatoduodenectomy is associated with the occurrence and development of secondary non-alcoholic fatty liver disease.


Assuntos
Diabetes Mellitus , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/cirurgia , Obesidade , Pancreaticoduodenectomia , Fatores de Risco
12.
Sci Total Environ ; 728: 138695, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32570312

RESUMO

Environmental flow is the quantity, timing, and quality of water flows required to sustain freshwater and estuarine ecosystems and the human livelihoods and well-being that depend on these ecosystems. Environmental flows (e-flows) are crucial parameters for ecosystem restoration. Understanding the effects of spatial variation in the hydrological and water quality factors on e-flows aids the determination of recovery prior areas and helps to improve the success rate of ecosystem restoration projects. However, few studies have investigated the effects, which severely hinder the restoration of aquatic ecosystems and the sustainable use of water resources in inland waters. This paper therefore presents a framework for studying such effects. Spatial autocorrelation, a geostatistical method, is used to analyze the spatial variation in the hydrological and water quality factors and to further analyze the effects of various factors on the spatial heterogeneity of e-flows. Four different methods including the Tennant method, wetted perimeter method, AEHRA, and integrated water quality method are integrated to comprehensively evaluate e-flows. The former three methods consider the demands of biota on the streamflow, whereas the latter considers the demands on both the streamflow and the water quality. The results show that the Tennant and wetted perimeter methods, which focus on the statistics of only streamflow, result in similar spatial distribution of e-flows; the AEHRA and integrated water quality method, which consider the effects of water quality and other hydrological factors such as flow velocity and water depth on fish, also result in a similar spatial variation. Consideration of both demands on the hydrological factors and the water quality environmental factors makes the integrated water quality method more practical, particularly in developing regions with excessive pollutant discharge into rivers. In addition, spatial variation in the hydrological and water quality factors influenced the presence of principal fish species and consequently affected the e-flows. Of the 37 water quality factors identified, water transparency had a negative impact on e-flow because the increase in transparency could reduce the number of principal fish species. Of the four hydrological factors, flow velocity and river width had positive impacts on fish because the increase in flow velocity can provide breeding sites and habitats for more fish, respectively, both of which result in increases in the numbers of principal fish species. We found that spatial variation in the hydrology and water quality factors had a profound impact on the living environments of aquatic organisms; negative changes in these factors lowered the survival probability of principal species, which changed the hierarchy and structure of the ecosystems and thus led to variation in e-flows. The results can provide priori knowledge for e-flow methods selection and a reference for ecosystem restoration helping improve the success rate of project elsewhere in the world.

13.
Sci Total Environ ; 693: 133571, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31377369

RESUMO

Inland streamflow estimation is essential in global water supply and environment protection. In data-scarce areas a highly efficient way of estimating streamflow is through remote sensing methods. However, high requirement of most previous methods on ground-measured data hinder their wide use in data-scarce areas. Therefore, this paper presented a new framework for estimation of streamflow in medium-to-small rivers with few ground measurements by using high-resolution unmanned aerial vehicle (UAV) imagery. A new Virtual Hydraulic Radius (VHR) method was proposed to complement AMHG (at-many-stations hydraulic geometry), a method not requiring any ground measurements when global parameters are used (global-AMHG) in large-scaled rivers but yielding great uncertainties in smaller scaled rivers, thus creating a VHR-AMHG method for medium-to-small rivers. The accuracy verification of the proposed method was performed by comparing it to field measurement data and the global parameters of the original AMHG (global-AMHG). Results showed that the root mean square error calculated from VHR-AMHG was 32.15 m3/s, while that from global-AMHG was 305.65 m3/s, indicating that the VHR-AHRG method yields a significantly higher accuracy for streamflow estimation for medium-to-small rivers. We found that regardless of the size of the river, AMHG is not applicable for rivers having excessively small b values in the equation w = aQb (low-b rivers). For medium-to-small rivers with b < 0.25, AMHG is not recommended. The accuracy of the original AMHG method is limited by the initial value of the model parameters and the condition that the congruent discharge (Qc) has to be within the range of observational discharge. The initial value setting of the model parameters significantly impacts the calculation accuracy. The VHR-AMHG method is able to overcome the deficiencies of the original AMHG, i.e. being overly dependent on the initial value setting with long-series known discharge data. It also eliminates the limitation of the Qc condition, as it achieves a higher accuracy for rivers in which Qc does not satisfy the condition compared to using global-AMHG on rivers that actually meet the condition, thus greatly expanding its usage scope. Thus VHR-AMHG method can provide detailed data on the spatial and temporal distribution of regional and national streamflow for governments and stakeholders, and offer scientific data support for wisely making water supply polices and sustainably protecting eco-environment.

14.
Zhonghua Gan Zang Bing Za Zhi ; 27(3): 232-235, 2019 Mar 20.
Artigo em Chinês | MEDLINE | ID: mdl-30929344

RESUMO

Hepatitis B virus (HBV) infection is the most common cause of hepatocellular carcinoma in China. Epidemiological surveys show that male have a much higher incidence of hepatocellular carcinoma than female. Studies have shown that estrogen and its receptors are associated to gender disparity in hepatocellular carcinoma, but the underlying molecular mechanisms has not yet been fully elucidated. This article reviews the possible mechanisms of estrogen and its receptors in the occurrence and progression of hepatitis B virus-related hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular , Hepatite B , Neoplasias Hepáticas , China , Estrogênios , Vírus da Hepatite B , Humanos
15.
Sci Total Environ ; 670: 837-848, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-30921717

RESUMO

With increased global warming, cyanobacteria are blooming more frequently in lakes and reservoirs, severely damaging the health and stability of aquatic ecosystems and threatening drinking water safety and human health. There is an urgent demand for the effective prediction and prevention of cyanobacterial blooms. However, it is difficult to effectively reduce the risks and loss caused by cyanobacterial blooms because most methods are unable to successfully predict cyanobacteria blooms. Therefore, in this study, we proposed a new cyanobacterial bloom occurrence prediction method to analyze the probability and driving factors of the blooms for effective prevention and control. Dominant cyanobacterial species with bloom capabilities were initially determined using a dominant species identification model, and the principal driving factors of the dominant species were then analyzed using canonical correspondence analysis (CCA). Cyanobacterial bloom probability was calculated using a newly-developed model, after which, the probable mutation points were identified and thresholds for the principal driving factors of cyanobacterial blooms were predicted. A total of 141 phytoplankton data sets from 90 stations were collected from six large-scale hydrology, water-quality ecology, integrated field surveys in Jinan City, China in 2014-2015 and used for model application and verification. The results showed that there were six dominant cyanobacterial species in the study area, and that the principal driving factors were water temperature, pH, total phosphorus, ammonia nitrogen, chemical oxygen demand, and dissolved oxygen. The cyanobacterial blooms corresponded to a threshold water temperature range, pH, total phosphorus (TP), ammonium nitrogen level, chemical oxygen demand, and dissolved oxygen levels of 19.5-32.5 °C, 7.0-9.38, 0.13-0.22 mg L-1, 0.38-0.63 mg L-1, 10.5-17.5 mg L-1, and 4.97-8.28 mg L-1, respectively. Comparison with research results from other global regions further supported the use of these thresholds, indicating that this method could be used in habitats beyond China. We found that the probability of cyanobacterial bloom was 0.75, a critical point for prevention and control. When this critical point was exceeded, cyanobacteria could proliferate rapidly, increasing the risk of cyanobacterial blooms. Changes in driving factors need to be rapidly controlled, based on these thresholds, to prevent cyanobacterial blooms. Temporal and spatial scales were critical factors potentially affecting the selection of driving factors. This method is versatile and can help determine the risk of cyanobacterial blooms and the thresholds of the principal driving factors. It can effectively predict and help prevent cyanobacterial blooms to reduce the global probability of occurrence, protect the health and stability of water ecosystems, ensure drinking water safety, and protect human health.


Assuntos
Cianobactérias/crescimento & desenvolvimento , Monitoramento Ambiental , Eutrofização , Microbiologia da Água , Lagos/microbiologia
16.
Water Res ; 153: 121-133, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30708191

RESUMO

Global aquatic ecosystems are essential to human existence and have deteriorated seriously in recent years. Understanding the influence mechanism of habitat variation on the structure of the food-web allows the effective recovery of the health of degraded ecosystems. Whereas most previous studies focused on the selection of driving habitat factors, the impact of habitat variation on the food-web structure was rarely studied, resulting in the low success rate of ecosystem restoration projects globally. This paper presents a framework for exploring the effects of spatial variations in water quality and hydrological habitat factors on the food-web structure in city waters. Indices for the evaluation of the food-web structure are first determined by integrating model-parameter extraction via literature refinement. The key water quality and hydrological factors are then determined by coupling canonical correspondence analysis with partial least squares regression. Their spatial variation is investigated using spatial autocorrelation. Finally, fuzzy clustering is applied to analyze the influence of the spatial variations in water quality and hydrological factors on the food-web structure. The results obtained in Ji'nan, the pilot city of water ecological civilization in China, show that the Shannon diversity index, connectance index, omnivory index, and the ratio of total primary production to the total respiration are important indicators of food-web structural change. They show that the driving factors affecting the aquatic food-web structure in Ji'nan are hydrological factors (e.g., river width, water depth, and stream flow), physical aspects of water quality (e.g., air temperature, water temperature, electrical conductivity, and transparency), and chemical aspects (e.g., potassium, dissolved oxygen, calcium, and total hardness). They also show that the stability of the food-web is more prone to spatial variations in water quality than in hydrological factors. Higher electrical conductivity, potassium, total hardness, and air temperature lead to deteriorated food-web structures, whereas better transparency improves structure and stability. We found that water and air temperature are the most important factors in the spatial variation of the food-web structure in the study area, followed by total hardness. Transparency is the least important factor. Large disparities and varied spatial distributions exist in the driving effects of water quality and hydrological factors across regions attributable to differences in geographical environments, water salinity (fresh vs. sea water), and environmental factors (e.g., water pollution). The above methods and results serve as a theoretical and scientific basis for a high success rate of aquatic ecosystem restoration projects in the study area and other cities worldwide.


Assuntos
Ecossistema , Qualidade da Água , China , Monitoramento Ambiental , Humanos , Hidrologia , Rios
17.
Sci Total Environ ; 665: 213-225, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30772551

RESUMO

Global algal blooms have been severely threatening safety of drinking water and development of socio-economy. Effective prevention and accurate control of algal blooms require a quantitative assessment of the influence of human activities and identification of priority areas. However, previous studies on the quantitative assessment of the effects of human activities on algal communities are lacking, severely hindering the effective and precise control of algal blooms. This paper proposes a quantitative assessment model to evaluate the impact intensity of human activities on phytoplankton. Applications showed that the proliferation of phytoplankton were more limited by nutrients such as total phosphorus and ammonia where waters are less influenced by human activities, yet were less limited by these nutrients where there are highly intensive human activities. The density of phytoplankton in waters increased with an increase in human activity intensity, particularly in concentrated agricultural areas, which are priority areas for the prevention and control of algal blooms. The methodologies can clearly identify key areas for algal bloom prevention and control and can provide scientific evidence for water and nutrient management throughout the world, reducing the risk of algal blooms and ensuring aquatic ecosystem health and potable water safety.


Assuntos
Monitoramento Ambiental , Lagos/química , Poluentes da Água/análise , Agricultura , Ecossistema , Eutrofização , Humanos , Nitrogênio/análise , Fósforo/análise , Fitoplâncton
18.
Sci Total Environ ; 656: 1373-1385, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30625666

RESUMO

It has been shown that climate change impacts the overall health of a river's ecosystem. Although predicting river health under climate change would be useful for stakeholders to adapt to the change and better conserve river health, little research on this topic exists. This paper presents a methodology predicting river health under different climate change scenarios. First, a multi-source, distributed, time-variant gain hydrological model (MS-DTVGM) was used to predict the runoff from a mountainous river in eastern China using the data from three existing IPCC5 climate change models (RCP2.6, RCP4.5, and RCP8.4). Next, a model was developed to predict the river's water quality under these scenarios. Finally, a multidimensional response model utilizing hydrology, water quality, and biology was used to predict the river's biological status and ascertain the impact of climate change on its overall health. The river is in a mountainous area near Jinan City, one of China's first "pilot" cities recognized as a "healthy water ecological community." Our results predict that the overall health of the Yufu River, which is minimally influenced by human activities, will improve by 2030 due to the increased river flow due to an increase in rainfall frequency and subsequent peak runoff. However, the total nitrogen concentration is predicted to increase, which is a potential eutrophication risk. Therefore, effective control of nitrogen pollutants entering the river will be necessary. The increase in flow velocity (the annual average increase is ~0.5 m/s) is favorable for fish reproduction. Our methods and results will provide scientific guidance for policy makers and river managers and will help people to better understand how global climate change impacts river health.

19.
BMC Plant Biol ; 18(1): 181, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-30185158

RESUMO

BACKGROUND: Sweetpotato (Ipomoea batatas (L.) Lam.) is one of the most important crops from the family of Convolvulaceae. It is widely reported that cultivated sweetpotato was originated from Ipomoea trifida. However, diploid, tetraploid and hexaploid I. trifida were found in nature. The relationship, between them, and among them and sweetpotato, is remaining unclear. RESULTS: In the present study, we detected the genome diversity and relationship of sweetpotato and different polyploidy types I. trifida using Restriction-site Associated DNA Sequencing (RAD-seq). A total of 38,605 RAD-tags containing 832,204 SNPs had been identified. These tags were annotated using five public databases, about 11,519 tags were aligned to functional genes in various pathways. Based on SNP genotype, phylogenetic relation analysis results confirmed that cultivated sweetpotato has a closer relationship with I. trifida 6× than with I. trifida 4X and I. trifida 2×. Besides, 5042 SSRs were detected in I. trifida 6×, and 3202 pairs of high-quality SSR primers were developed. A total of 68 primers were randomly selected and synthesized, of which 61 were successfully amplified. CONCLUSION: These results provided new evidence that cultivated sweetpotato originated from I. trifida 6×, and that I. trifida 6× evolved from I. trifida 4X and I. trifida 2×. Therefore, using I. trifida 6× as the model plant of sweetpotato research should be more practical than using I. trifida 2× in the future. Meanwhile, sequence information and markers from the present study will be helpful for sweetpotato and I. trifida studies in the future.


Assuntos
Evolução Molecular , Variação Genética , Ipomoea/genética , Poliploidia , Análise de Sequência de DNA/métodos , DNA de Plantas , Marcadores Genéticos , Especiação Genética , Ipomoea batatas/genética , Repetições de Microssatélites , Filogenia , Polimorfismo de Nucleotídeo Único
20.
Opt Lett ; 43(11): 2462-2465, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29856404

RESUMO

The fifth harmonic of a pulsed Nd:YLF laser has been realized in a cascade of nonlinear crystals with a record efficiency of 30%. Cesium lithium borate is used in a Type-I configuration for sum-frequency mixing of 1053 and 266 nm, producing 211 nm pulses. Flat-topped beam profiles and pulse shapes optimize efficiency. The energies of the fifth harmonic up to 335 mJ in 2.4 ns pulses were demonstrated.

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