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1.
BMC Public Health ; 24(1): 1358, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769474

RESUMO

BACKGROUND: Understanding factors associated with antiretroviral treatment (ART) adherence is crucial for ART success among people living with HIV (PLHIV) in the "test and treat" era. Multiple psychosocial factors tend to coexist and have a syndemic effect on ART adherence. We aimed to explore factors associated with ART adherence and the syndemic effect of multiple psychosocial factors on ART adherence among PLHIV newly starting ART in Guangdong Province, China. METHODS: Newly diagnosed PLHIV from six cities in Guangdong Province were recruited between May 2018 and June 2019, and then followed up from May 2019 to August 2020. Baseline and follow-up data were collected from a questionnaire and the national HIV surveillance system, the follow-up data of which were analyzed in this study. A Center for Adherence Support Evaluation (CASE) index > 10 points was defined as optimal ART adherence, which was measured via participants' self-reported adherence during follow-up survey. Multivariable logistic regression was used to identify factors associated with ART adherence. Exploratory factor analysis (EFA) and multi-order latent variable structural equation modeling (SEM) were performed to explore the syndemic effect of multiple psychosocial factors on ART adherence. RESULTS: A total of 734 (68.53%) follow-up participants were finally included in this study among the 1071 baseline participants, of whom 91.28% (670/734) had self-reported optimal ART adherence. Unemployment (aOR = 1.75, 95%CI: 1.01-3.02), no medication reminder (aOR = 2.28, 95%CI: 1.09-4.74), low medication self-efficacy (aOR = 2.28, 95%CI: 1.27-4.10), low social cohesion (aOR = 1.82, 95%CI: 1.03-3.19), no social participation (aOR = 5.65, 95%CI: 1.71-18.63), and ART side effects (aOR = 0.46, 95%CI: 0.26-0.81) were barriers to optimal ART adherence. The EFA and second-order latent variable SEM showed a linear relationship (standardized coefficient = 0.43, P < 0.001) between ART adherence and the latent psychosocial (syndemic) factor, which consisted of the three latent factors of medication beliefs and self-efficacy (standardized coefficient = 0.65, P < 0.001), supportive environment (standardized coefficient = 0.50, P < 0.001), and negative emotions (standardized coefficient=-0.38, P < 0.01). The latent factors of medication beliefs and self-efficacy, supportive environment, and negative emotions explained 42.3%, 25.3%, and 14.1% of the variance in the latent psychosocial factor, respectively. CONCLUSIONS: About nine out of ten PLHIV on ART in Guangdong Province self-reported optimal ART adherence. However, more efforts should be made to address barriers to optimal ART adherence.


Assuntos
Infecções por HIV , Adesão à Medicação , Humanos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/psicologia , China/epidemiologia , Masculino , Feminino , Adulto , Estudos Transversais , Adesão à Medicação/estatística & dados numéricos , Adesão à Medicação/psicologia , Pessoa de Meia-Idade , Antirretrovirais/uso terapêutico , Inquéritos e Questionários , Fármacos Anti-HIV/uso terapêutico , Adulto Jovem
2.
Sci Total Environ ; 930: 172671, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38653407

RESUMO

Soil acidification often suppresses microbial growth and activities, resulting in a negative impact on soil organic carbon (C) decomposition. While the detrimental effects of acidification on soil and plant properties have been extensively studied, less attention has been paid on the shifts in soil microbial communities and their influences of the decomposition of organic C with different chemical complexities. Taking advantage of an acid addition experiment in a Tibetan alpine meadow, here we examined the response of soil microbial communities to soil acidification and microbial effect on the decomposition of organic C with different chemical complexities (i.e., glucose and lignin, representing labile and recalcitrant C respectively). We found that soil acidification had no impact on microbial respiration and microbial abundance even though it decreased bacterial diversity significantly. Soil acidification increased the relative abundance of some microbial taxa, like Alphaproteobacteria and Acidobacteriia in bacteria increased by 36 %, 284 %, and Eurotiomycetes, Sordariomycetes and Leotiomycetes in fungi increased by 145 %, 279 % and 12.7-fold, but decreased the relative abundance of Acidimicrobiia by 33 % in highest acid addition treatment. Changes in microbial communities (bacterial and fungal community composition, the diversity of bacterial community and the ratio of fungi to bacteria) are significantly related to the decomposition of glucose and lignin. More specifically, soil acidification decreased the decomposition of glucose but increased the decomposition of lignin, indicating a trade-off between the decomposition of labile and recalcitrant soil organic C under soil acidification. Overall, shifts in microbial communities under soil acidification might be accompanied by an increased ability to break down more recalcitrant C. This trade-off between the decomposition of labile and recalcitrant C may change soil C quality under future acid deposition scenarios.


Assuntos
Glucose , Pradaria , Lignina , Microbiota , Microbiologia do Solo , Solo , Solo/química , Glucose/metabolismo , Bactérias , Concentração de Íons de Hidrogênio , Tibet , Fungos
3.
Nat Commun ; 15(1): 2695, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538640

RESUMO

Global potent greenhouse gas nitrous oxide (N2O) emissions from soil are accelerating, with increases in the proportion of reactive nitrogen emitted as N2O, i.e., N2O emission factor (EF). Yet, the primary controls and underlying mechanisms of EFs remain unresolved. Based on two independent but complementary global syntheses, and three field studies determining effects of acidity on N2O EFs and soil denitrifying microorganisms, we show that soil pH predominantly controls N2O EFs and emissions by affecting the denitrifier community composition. Analysis of 5438 paired data points of N2O emission fluxes revealed a hump-shaped relationship between soil pH and EFs, with the highest EFs occurring in moderately acidic soils that favored N2O-producing over N2O-consuming microorganisms, and induced high N2O emissions. Our results illustrate that soil pH has a unimodal relationship with soil denitrifiers and EFs, and the net N2O emission depends on both the N2O/(N2O + N2) ratio and overall denitrification rate. These findings can inform strategies to predict and mitigate soil N2O emissions under future nitrogen input scenarios.


Assuntos
Agricultura , Solo , Solo/química , Óxido Nitroso/análise , Fertilizantes/análise , Nitrogênio , Concentração de Íons de Hidrogênio , Microbiologia do Solo , Desnitrificação
4.
Sci Total Environ ; 920: 170979, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38367727

RESUMO

Organic amendments can improve soil fertility and microbial diversity, making agroecosystems more resilient to stress. However, it is uncertain whether organic amendments will enhance the functional capacity of soil microbial communities, thereby mitigating fluctuations in microbial respiration caused by environmental changes. Here, we examined the impacts of long-term organic amendments on the dynamics of microbial catabolic capacity (characterized by enzyme activities and carbon source utilization) and microbial respiration, as well as their interrelationships during a period with fluctuating temperature and rainfall in the field. We then subjected the field soil samples to laboratory heating disturbances to further evaluate the importance of microbial catabolic capacity in explaining patterns of microbial respiration. In both field and laboratory experiments, organic amendments tended to increase the stability of microbial catabolic capacity, but significantly increased the vulnerability of microbial respiration to environmental changes. However, the direction and driving factors of microbial respiration affected by environmental changes differed between the field and laboratory experiments. Environmental changes in the field suppressed the promotional effects of organic amendments on microbial respiration mainly through reducing microbial catabolic capacity, while laboratory heating further enhanced microbial respiration mainly due to increased soil resource availability. Together, these findings suggest that increased microbial respiration variations under organic amendments may potentially increase the uncertainty in predicting soil carbon emissions in the scenario of ongoing climate/anthropogenic changes, and highlight the necessity of linking laboratory studies on environmental changes to field conditions.


Assuntos
Carbono , Microbiologia do Solo , Carbono/metabolismo , Solo , Temperatura
6.
Int J Mol Sci ; 24(3)2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36768487

RESUMO

Cuticular proteins (CPs) are a large family and perform a variety of functions. However, the physiological roles of cuticle protein 21-like (Cpr21L) in the brown planthopper (Nilaparvata lugens, BPH), one of the most destructive insect pests of rice, are largely unclear. In this study, Cpr21L was revealed to be expressed in both BPH nymphs and adults, and the mRNA expression level was much higher in male adults than female adults. Spatially, the expression of Cpr21L in the testis was higher than in the ovary. The RNA interference (RNAi) of Cpr21L seriously decreased nymph survival, and no individual survived 8 days post-dsCpr21L injection. The RNAi of Cpr21L in adults also decreased the fertility of males, especially in the dsCpr21L♂ × dsGFP♀ group. The average number of eggs laid by one female in this group significantly decreased by 50.1%, and the eggs' hatchability decreased from 76.5% to 23.8% compared with the control (dsGFP♂ × dsGFP♀). Furthermore, observations under a stereomicroscope showed that the RNAi of Cpr21L severely impaired the development of the testes. Therefore, Cpr21L is essential for the nymphal survival and male fecundity of BPH, thus providing a possible target for pest control.


Assuntos
Hemípteros , Oryza , Animais , Feminino , Fertilidade/genética , Ninfa , Oryza/genética , Ovário , Interferência de RNA
7.
Glob Chang Biol ; 28(24): 7410-7427, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36149390

RESUMO

Dissolved organic matter (DOM) plays a vital role in biogeochemical processes and in determining the responses of soil organic matter (SOM) to global change. Although the quantity of soil DOM has been inventoried across diverse spatio-temporal scales, the underlying mechanisms accounting for variability in DOM dynamics remain unclear especially in upland ecosystems. Here, a gradient of SOM storage across 12 croplands in northeast China was used to understand links between DOM dynamics, microbial metabolism, and abiotic conditions. We assessed the composition, biodegradability, and key biodegradable components of DOM. In addition, SOM and mineral-associated organic matter (MAOM) composition, soil enzyme activities, oxygen availability, soil texture, and iron (Fe), Fe-bound organic matter, and nutrient concentrations were quantified to clarify the drivers of DOM quality (composition and biodegradability). The proportion of biodegradable DOM increased exponentially with decreasing initial DOM concentration due to larger fractions of depolymerized DOM that was rich in small-molecular phenols and proteinaceous components. Unexpectedly, the composition of DOM was decoupled from that of SOM or MAOM, but significantly related to enzymatic properties. These results indicate that microbial metabolism exhibited a dominant role in DOM generation. As DOM concentration declined, increased soil oxygen availability regulated DOM composition and enhanced its biodegradability mainly through mediating microbial metabolism and Fe oxidation. The oxygen-induced oxidation of Fe(II) to Fe(III) removed complex DOM compounds with large molecular weight. Moreover, increased oxygen availability stimulated oxidase-catalyzed depolymerization of aromatic substances, and promoted production of protein-like DOM components due to lower enzymatic C/N acquisition ratio. As global changes in temperature and moisture will have large impacts on soil oxygen availability, the role of oxygen in regulating DOM dynamics highlights the importance of integrating soil oxygen supply with microbial metabolism and Fe redox status to improve model predictions of soil carbon under climate change.


Assuntos
Ferro , Solo , Solo/química , Matéria Orgânica Dissolvida , Ecossistema , Oxigênio , Oxirredução
8.
Front Pediatr ; 10: 774973, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35356442

RESUMO

Background: Urethrocutaneous fistula is one of the most common complications arising from hypospadias surgery. The purpose of our study was to investigate the effectiveness and safety of allogeneic human acellular dermal matrix (HADM) application as a means of preventing the occurrence of urethrocutaneous fistula following hypospadias surgery. Methods: This is a non-randomized study of 219 cases (out of 270 patients with hypospadias) which satisfied inclusion and exclusion criteria. These patients were divided into two groups: 101 HADM patients, and 118 control patients (who did not receive HADM). In the control group, 77 boys were treated by single-stage urethroplasty (TIP) and 41 underwent staged urethroplasty (Thiersch-Duplay). In the HADM group, 59 boys underwent the TIP and 42 underwent the Thiersch-Duplay. In the postoperative period, we recorded the incidence of infection, urethrocutaneous fistula, and urethral stricture complications in these two groups of patients. The effectiveness and safety of HADM in preventing urethrocutaneous fistula following hypospadias surgery were evaluated according to these indicators. Results: In the control group, following the operation there were 16 cases of infection, 38 cases of urethrocutaneous fistula after extubating, and 5 cases of urethral stricture. In the HADM group, there were 19 cases of postoperative infection, 12 cases of urethrocutaneous fistula after extubating, and 5 children with urethral stricture. In comparing the two groups, it was found that the postoperative infection rate (13.6 vs. 18.8%) and the incidence of urethral stricture (4.2 vs. 5.0%) were not statistically significant (P > 0.05), while the postoperative urethrocutaneous fistula rate (32.2 vs. 11.9%) was statistically significant (P < 0.001). Conclusion: It is found that HADM application can significantly reduce the incidence of urethrocutaneous fistula complications, without increasing the risk of infection and urethral stricture.

9.
J Agric Food Chem ; 70(9): 2839-2850, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35226488

RESUMO

Transferrins are multifunctional proteins, but their role in the interaction of rice and brown planthopper (BPH) remains unclear. In this study, the full-length cDNA of transferrin genes NlTsf1, NlTsf2, and NlTsf3 was cloned. Reverse transcription quantitative polymerase chain reaction showed that the expressions of NlTsf1 and NlTsf3 were significantly suppressed in BPH reared on the resistant rice R1 by 68.0 and 86.7%, respectively, compared with that on the susceptible S9. The survival rate decreased to 3.3% for dsNlTsf3-treated nymphs, to 58.9% for dsNlTsf1, and to 56.7% for dsNlTsf2 on day 11. RNAi of NlTsf3 against females largely reduced the number of eggs by 99.4%, and it decreased by 48.6% for dsNlTsf1 but did not significantly decrease for dsNlTsf2. Collectively, NlTsf1, NlTsf2, and NlTsf3 are essential for the survival and fecundity of BPH and are differentially involved in the interaction between rice and BPH. Therefore, NlTsf1 and NlTsf3 may be used as targets to control BPH.


Assuntos
Hemípteros , Oryza , Animais , Feminino , Hemípteros/genética , Hemípteros/metabolismo , Ninfa/genética , Ninfa/metabolismo , Oryza/genética , Oryza/metabolismo , Interferência de RNA , Transferrinas/genética , Transferrinas/metabolismo
10.
Dig Dis ; 40(6): 796-809, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34937035

RESUMO

BACKGROUND: Traditional endoscopic submucosal dissection (ESD) has developed different methods, such as pocket method (P-ESD), traction-assisted method (T-ESD), and hybrid method (H-ESD). In this meta-analysis, the benefits and drawbacks of different ESD methods were discussed and ranked. STUDY DESIGN: Studies comparing different methods of colorectal ESD were searched by using PubMed, EMBASE, and Cochrane Library databases. The study was conducted for five endpoints: en bloc resection rate, R0 resection rate, operation time, dissection speed, and adverse events rate. Pairwise and network meta-analyses were performed through Rev Man 5.4 and Stata 16.0. The quality of all included studies was assessed using the Cochrane Risk of Bias Tool and the Newcastle-Ottawa Scale. RESULTS: Twenty-six studies met the inclusion criteria, including 7 RCTs and 19 non-RCTs, with a total of 3,002 patients. The pooled analysis showed that the en bloc resection rate of H-ESD was significantly lower than that of C-ESD, P-ESD, and T-ESD (RR = 0.28, 95% CI [0.12, 0.65]; RR = 0.11, 95% CI [0.03, 0.44]; RR = 8.28, 95% CI [2.50, 27.42]). Compared with C-ESD, the operation time of H-ESD and T-ESD was significantly shorter (MD = -21.83, 95% CI [-34.76, -8.90]; MD = -23.8, 95% CI [-32.55, -15.06]). Meanwhile, the operation time of T-ESD was also significantly shorter than that of P-ESD (MD = -18.74, 95% CI [-31.93, -5.54]). The dissection speed of T-ESD was significantly faster than that of C-ESD (MD = 6.26, 95% CI [2.29, 10.23]). CONCLUSION: P-ESD and T-ESD are probably the two best methods of colorectal ESD at present. The advantages of P-ESD are high en bloc resection rate and low incidence of adverse events. The advantages of T-ESD are rapid dissection and short operation time.


Assuntos
Neoplasias Colorretais , Ressecção Endoscópica de Mucosa , Humanos , Ressecção Endoscópica de Mucosa/efeitos adversos , Metanálise em Rede , Resultado do Tratamento , Dissecação/métodos , Neoplasias Colorretais/cirurgia , Estudos Retrospectivos
11.
Glob Chang Biol ; 27(23): 6166-6180, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34464997

RESUMO

Oxygen (O2 ) limitation contributes to persistence of large carbon (C) stocks in saturated soils. However, many soils experience spatiotemporal O2  fluctuations impacted by climate and land-use change, and O2 -mediated climate feedbacks from soil greenhouse gas emissions remain poorly constrained. Current theory and models posit that anoxia uniformly suppresses carbon (C) decomposition. Here we show that periodic anoxia may sustain or even stimulate decomposition over weeks to months in two disparate soils by increasing turnover and/or size of fast-cycling C pools relative to static oxic conditions, and by sustaining decomposition of reduced organic molecules. Cumulative C losses did not decrease consistently as cumulative O2 exposure decreased. After >1 year, soils anoxic for 75% of the time had similar C losses as the oxic control but nearly threefold greater climate impact on a CO2 -equivalent basis (20-year timescale) due to high methane (CH4 ) emission. A mechanistic model incorporating current theory closely reproduced oxic control results but systematically underestimated C losses under O2  fluctuations. Using a model-experiment integration (ModEx) approach, we found that models were improved by varying microbial maintenance respiration and the fraction of CH4 production in total C mineralization as a function of O2 availability. Consistent with thermodynamic expectations, the calibrated models predicted lower microbial C-use efficiency with increasing anoxic duration in one soil; in the other soil, dynamic organo-mineral interactions implied by our empirical data but not represented in the model may have obscured this relationship. In both soils, the updated model was better able to capture transient spikes in C mineralization that occurred following anoxic-oxic transitions, where decomposition from the fluctuating-O2 treatments greatly exceeded the control. Overall, our data-model comparison indicates that incorporating emergent biogeochemical properties of soil O2 variability will be critical for effectively modeling C-climate feedbacks in humid ecosystems.


Assuntos
Carbono , Solo , Dióxido de Carbono/análise , Ecossistema , Metano , Oxigênio
12.
Pest Manag Sci ; 77(10): 4658-4668, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34092014

RESUMO

BACKGROUND: The brown planthopper (BPH), Nilaparvata lugens, is a serious insect pest of rice. Autophagy and its related gene ATG3 play multiple roles in insects. However, information about the functions of ATG3 in BPH (NlATG3) is unavailable, and its potential as a target for pest control remains unclear. RESULTS: RT-qPCR results showed a relatively low expression of NlATG3 in 1st-4th-instar nymphs, which increased through 9-day-old adults. The expression of NlATG3 increased continuously in 1-day-old through 5-day-old eggs, whereas it decreased thereafter. The mRNA level of NlATG3 was markedly higher in the ovary (1.16) and head (1.00) compared to the rest body parts of BPH adults. Injecting nymphs with dsNlATG3 at doses from 62.5 to 250 ng per insect had strong lethal effect upon them. For the 5th-instar nymphs, all individuals died within 5 days after receiving the dsNlATG3, and importantly, no individual successfully molted. Transmission electron microscopy revealed the new cuticle of nymphs injected with dsNlATG3 became loose and curved, which is clearly different from that of the control. Correspondingly, the obvious vesicles in epidermal cells disappeared after dsNlATG3-treatment. RNAi of NlATG3 significantly reduced the total number of eggs laid per female as well as the eggs' hatchability, especially in the dsNlATG3♀ × dsGFP♂ group, whose total number of eggs laid per female largely decreased by 80.4%, and whose eggs' hatchability was significantly reduced from 95.7% to zero, when compared with the control (dsGFP♀ × dsGFP♂). CONCLUSION: NlATG3 is a promising target for developing RNAi-based insect management strategies. © 2021 Society of Chemical Industry.


Assuntos
Hemípteros , Animais , Autofagia , Feminino , Fertilidade , Hemípteros/genética , Humanos , Ninfa/genética , Interferência de RNA
13.
Acad Radiol ; 28(5): 687-693, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32418785

RESUMO

OBJECTIVE: Different grades of meningiomas require different treatment strategies and have a different prognosis; thus, the noninvasive classification of meningiomas before surgery is of great importance. The purpose of this study was to explore the application value of magnetic resonance imaging (MRI) radiomics based on enhanced-T1-weighted (T1WI) images in the prediction of meningiomas grade. MATERIALS AND METHODS: A total of 98 patients with meningiomas who were confirmed by surgical pathology and underwent preoperative routine MRI between January 2017 and December 2019 were analyzed. There were 82 cases of low-grade meningiomas (WHO grade I) and 16 cases of high-grade meningiomas (7 cases of WHO grade II and 9 cases of WHO grade III). These patients were randomly divided into a training group and test group according to 7:3 ratio. The lesions were manually delineated using ITK-SNAP software, and radiomics analysis were performed using the Analysis Kit (AK) software. A total of 396 tumor texture features were extracted. Subsequently, the LASSO algorithm was used to reduce the feature dimensions. Next, a prediction model was constructed using the Logistic Regression method and receiver operator characteristic was used to evaluate the prediction performance of the model. RESULTS: A radiomics prediction model was constructed based on the selected nine characteristic parameters, which performed well in predicting the meningiomas grade. The accuracy rates in the training group and the test group were respectively 94.3% and 92.9%, the sensitivities were respectively 94.8%, and 91.7%, the specificities were respectively 91.7% and 100%, and the area under the curve values were respectively 0.958 and 0.948. CONCLUSION: The MRI radiomics method based on enhanced-T1WI images has a good predictive effect on the classification of meningiomas and can provide a basis for planning clinical treatment protocols.


Assuntos
Neoplasias Meníngeas , Meningioma , Algoritmos , Humanos , Imageamento por Ressonância Magnética , Neoplasias Meníngeas/diagnóstico por imagem , Meningioma/diagnóstico por imagem , Curva ROC , Estudos Retrospectivos
14.
Glob Chang Biol ; 26(9): 5320-5332, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32533721

RESUMO

The ongoing global change is multi-faceted, but the interactive effects of multiple drivers on the persistence of soil carbon (C) are poorly understood. We examined the effects of warming, reactive nitrogen (N) inputs (12 g N m-2  year-1 ) and altered precipitation (+ or - 30% ambient) on soil aggregates and mineral-associated C in a 4 year manipulation experiment with a semi-arid grassland on China's Loess Plateau. Our results showed that in the absence of N inputs, precipitation additions significantly enhanced soil aggregation and promoted the coupling between aggregation and both soil fungal biomass and exchangeable Mg2+ . However, N inputs negated the promotional effects of increased precipitation, mainly through suppressing fungal growth and altering soil pH and clay-Mg2+ -OC bridging. Warming increased C content in the mineral-associated fraction, likely by increasing inputs of root-derived C, and reducing turnover of existing mineral-associated C due to suppression of fungal growth and soil respiration. Together, our results provide new insights into the potential mechanisms through which multiple global change factors control soil C persistence in arid and semi-arid grasslands. These findings suggest that the interactive effects among global change factors should be incorporated to predict the soil C dynamics under future global change scenarios.


Assuntos
Carbono , Solo , Ecossistema , Pradaria , Nitrogênio/análise
15.
Glob Chang Biol ; 26(6): 3726-3737, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32227617

RESUMO

Oxygen (O2 ) limitation is generally understood to suppress oil carbon (C) decomposition and is a key mechanism impacting terrestrial C stocks under global change. Yet, O2 limitation may differentially impact kinetic or thermodynamic versus physicochemical C protection mechanisms, challenging our understanding of how soil C may respond to climate-mediated changes in O2 dynamics. Although O2 limitation may suppress decomposition of new litter C inputs, release of physicochemically protected C due to iron (Fe) reduction could potentially sustain soil C losses. To test this trade-off, we incubated two disparate upland soils that experience periodic O2 limitation-a tropical rainforest Oxisol and a temperate cropland Mollisol-with added litter under either aerobic (control) or anaerobic conditions for 1 year. Anoxia suppressed total C loss by 27% in the Oxisol and by 41% in the Mollisol relative to the control, mainly due to the decrease in litter-C decomposition. However, anoxia sustained or even increased decomposition of native soil-C (11.0% vs. 12.4% in the control for the Oxisol and 12.5% vs. 5.3% in the control for the Mollisol, in terms of initial soil C mass), and it stimulated losses of metal- or mineral-associated C. Solid-state 13 C nuclear magnetic resonance spectroscopy demonstrated that anaerobic conditions decreased protein-derived C but increased lignin- and carbohydrate-C relative to the control. Our results indicate a trade-off between physicochemical and kinetic/thermodynamic C protection mechanisms under anaerobic conditions, whereby decreased decomposition of litter C was compensated by more extensive loss of mineral-associated soil C in both soils. This challenges the common assumption that anoxia inherently protects soil C and illustrates the vulnerability of mineral-associated C under anaerobic events characteristic of a warmer and wetter future climate.


Assuntos
Carbono , Solo , Anaerobiose , Mudança Climática , Lignina
16.
Korean J Radiol ; 21(4): 501-504, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32100486

RESUMO

From December 2019, Coronavirus disease 2019 (COVID-19) pneumonia (formerly known as the 2019 novel Coronavirus [2019-nCoV]) broke out in Wuhan, China. In this study, we present serial CT findings in a 40-year-old female patient with COVID-19 pneumonia who presented with the symptoms of fever, chest tightness, and fatigue. She was diagnosed with COVID-19 infection confirmed by real-time reverse-transcriptase-polymerase chain reaction. CT showed rapidly progressing peripheral consolidations and ground-glass opacities in both lungs. After treatment, the lesions were shown to be almost absorbed leaving the fibrous lesions.


Assuntos
Infecções por Coronavirus/diagnóstico por imagem , Pneumonia Viral/diagnóstico por imagem , Adulto , COVID-19 , Feminino , Febre/etiologia , Humanos , Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X
17.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(3): 250-255, 2019 May 28.
Artigo em Chinês | MEDLINE | ID: mdl-31257808

RESUMO

OBJECTIVE: To investigate the protective effects of procyanidin on periprosthetic osteolysis caused by tricalcium phosphate (TCP) wear particles in the mouse calvaria and its mechanism. METHODS: Forty-eight male ICR mice were randomly divided into sham group, TCP group, and procyanidin (0.2 mg/kg, 1 mg/kg, 5 mg/kg)-treated group (n=12). A periprosthetic osteolysis model in the mouse calvaria was established by implanting 30 mg of TCP wear particles onto the surface of bilateral parietal bones following removal of the periosteum. On the 2nd day post-operation, procyanidin (1 mg/kg, 5 mg/kg) was locally injected to the calvaria under the periosteum every other day. After 2 weeks, all the mice were sacrificed to collect the blood samples and the calvaria. Periprosthetic osteolysis and osteoclastogenesis in the mouse calvaria were observed by tartrate resistant acid phosphatase (TRAP) staining and HE staining. mRNA levels of TRAP, capthesin K, c-Fos and NFATc1 in the periprosthestic bone tissue were examined by real-time fluorescence quantitative PCR. Serum contents of total anti-oxidation capacity (T-AOC) and MDA, and superoxide dismutase (SOD) activity were determined by chemical colorimetry. Protein expressions of autophagic biomarkers such as Beclin-1 and LC-3 in periprosthetic bone tissue of the calvaria were examined by Western blot. RESULTS: Compared with sham group, periprosthetic osteolysis, osteoclastogenesis, mRNA levels of TRAP, capthesin K, c-Fos and NFATc1, and serum MDA content were increased significantly in the TCP group (P<0.05), whereas serum T-AOC level and SOD activity were decreased. The protein expressions of Beclin-1 and LC-3, and the conversion of LC3-II from LC3-I were both up-regulated markedly in the mouse calvaria of TCP group (P<0.05). Compared with TCP group, osteolysis, osteoclastogenesis, mRNA levels of TRAP, capthesin K, c-Fos and NFATc1 and serum MDA content were decreased obviously in the procyanidine group (P<0.05), serum T-AOC level and SOD activity were increased, the expressions of Beclin-1 and LC-3, and the conversion of LC3-II from LC3-I were down-regulated obviously in the mouse calvaria of procyanidin group (P<0.05). CONCLUSION: Procyanidin has a protective effect of periprosthetic osteolysis caused by TCP wear particles in the mouse calvaia, its mechanism may be mediated by inhibition of oxidative stress and autophagy.


Assuntos
Biflavonoides/farmacologia , Fosfatos de Cálcio/efeitos adversos , Catequina/farmacologia , Osteólise , Proantocianidinas/farmacologia , Próteses e Implantes/efeitos adversos , Animais , Autofagia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Estresse Oxidativo , Distribuição Aleatória , Crânio
18.
Front Physiol ; 10: 1622, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32082181

RESUMO

Autophagy plays multiple roles in regulating various physiological processes in cells. However, we currently lack a systematic analysis of autophagy and the autophagy-related gene 1 ATG1 in the brown planthopper (BPH, Nilaparvata lugens), one of the most destructive of the insect pests of rice. In this study, the full-length cDNA of an autophagy-related gene, NlATG1, was cloned from BPH. Real-time qPCR (RT-qPCR) revealed that this NlATG1 gene was expressed differently across developmental stages, at higher levels in nymphs but lower levels in adults. RNA interference with dsNlATG1 significantly decreased the mRNA level of the target gene to 14.6% at day 4 compared with that of the dsGFP control group. The survival of the dsNlATG1-treated group decreased significantly from day 4 onward, dropping to 48.3% on day 8. Examination using transmission electron microscopy (TEM) showed that epithelial cells of the BPH's midgut in the dsNlATG1-treated group had less autophagic vacuoles than did the dsGFP control, and knockdown of NlATG1 clearly inhibited the starvation-induced autophagy response in this insect. RNA interference of NlATG1 upregulated the NlFis1 gene involved in mitochondrial fission, leading to reductions in mitochondrial width and area. Furthermore, knockdown of NlATG1 also decreased the ATP content and accumulation of glycogen. Together, these results demonstrate that the NlATG1 gene participates in regulating autophagy and fission of mitochondria in the brown planthopper, making it a potentially promising target for pest control given its key role in autophagy, including maintaining the normal structure and function of mitochondria.

19.
Front Neurol ; 9: 363, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29951028

RESUMO

Impaired spontaneous regional activity and altered topology of the brain network have been observed in obstructive sleep apnea (OSA). However, the mechanisms of disrupted functional connectivity (FC) and topological reorganization of the default mode network (DMN) in patients with OSA remain largely unknown. We explored whether the FC is altered within the DMN and examined topological changes occur in the DMN in patients with OSA using a graph theory analysis of resting-state functional magnetic resonance imaging data and evaluated the relationship between neuroimaging measures and clinical variables. Resting-state data were obtained from 46 male patients with untreated severe OSA and 46 male good sleepers (GSs). We specifically selected 20 DMN subregions to construct the DMN architecture. The disrupted FC and topological properties of the DMN in patients with OSA were characterized using graph theory. The OSA group showed significantly decreased FC of the anterior-posterior DMN and within the posterior DMN, and also showed increased FC within the DMN. The DMN exhibited small-world topology in both OSA and GS groups. Compared to GSs, patients with OSA showed a decreased clustering coefficient (Cp) and local efficiency, and decreased nodal centralities in the left posterior cingulate cortex and dorsal medial prefrontal cortex, and increased nodal centralities in the ventral medial prefrontal cortex and the right parahippocampal cortex. Finally, the abnormal DMN FC was significantly related to Cp, path length, global efficiency, and Montreal cognitive assessment score. OSA showed disrupted FC within the DMN, which may have contributed to the observed topological reorganization. These findings may provide further evidence of cognitive deficits in patients with OSA.

20.
Front Plant Sci ; 9: 710, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29896209

RESUMO

Brown planthopper (BPH) Nilaparvata lugens Stål is a serious insect pest of rice in Asian countries. Active compounds have close relationship with rice resistance against BPH. In this study, HPLC, MS/MS, and NMR techniques were used to identify active compounds in total flavonoids of rice. As a result, a BPH resistance-associated compound, Peak 1 in HPLC chromatogram of rice flavonoids, was isolated and identified as schaftoside. Feeding experiment with artificial diet indicated that schaftoside played its role in a dose dependent manner, under the concentration of 0.10 and 0.15 mg mL-1, schaftoside showed a significant inhibitory effect on BPH survival (p < 0.05), in comparison with the control. The fluorescent spectra showed that schaftoside has a strong ability to bind with NlCDK1, a CDK1 kinase of BPH. The apparent association constant KA for NlCDK1 binding with schaftoside is 6.436 × 103 L/mol. Docking model suggested that binding of schaftoside might affect the activation of NlCDK1 as a protein kinase, mainly through interacting with amino acid residues Glu12, Thr14 and Val17 in the ATP binding element GXGXXGXV (Gly11 to Val18). Western blot using anti-phospho-CDK1 (pThr14) antibody confirmed that schaftoside treatment suppressed the phosphorylation on Thr-14 site of NlCDK1, thus inhibited its activation as a kinase. Therefore, this study revealed the schaftoside-NlCDK1 interaction mode, and unraveled a novel mechanism of rice resistance against BPH.

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