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Background: Optimal treatments for severe alcoholic hepatitis (SAH) remain controversial. Previous network meta-analysis showed that corticosteroid (CS) combined with N-acetylcysteine (NAC) was superior in reducing short-term mortality of patients with SAH. Recently, granulocyte colony-stimulating factor (G-CSF) treatments for SAH yielded promising results.Objectives: To determine how currently available treatments affect the survival and complications of patients with SAH.Methods: The study was conducted following the guidelines of PRISMA. The data from PubMed, Embase, MEDLINE, Cochrane Library, and clinicaltrials.gov to October 2022 were searched, and patients with SAH with pharmacotherapy were included in our study. The primary outcome was short-term survival, and the other outcomes were medium- (3/6 months) or long-term (12 months) survival and complications after treatment. R software was used to establish network meta-analysis models and the result was expressed by the odd ratio (OR) value and 95% credible interval (Crls).Results: A total of 31 randomized controlled trials, including 19 treatment regimens, were enrolled in our study. As the primary outcome, G-CSF+ pentoxifylline (PTX) ranked first in one-month survival and showed significant superiority when compared with the placebo (OR 8.60, 95% Crls 1.92-45.10) and CS (OR 4.95, 95% Crls 1.11-25.53). Also, G-CSF+PTX ranked first in improving three-month survival and reducing the occurrence of infection. PTX+MTD ranked first in six-month survival, and G-CSF ranked first in twelve-month survival. CS+MTD ranked first in the occurrence of gastrointestinal bleeding and hepatorenal syndrome.Conclusions: The combination of G-CSF and PTX showed a significant benefit in improving the short-term survival of SAH patients.
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Background: The burden of alcohol-related liver disease (ARLD) is increasing in China. Patients with ARLD are more likely to have comorbid sarcopenia, which may impair their survival. This study aimed to evaluate the relationship between the prognoses of patients with ARLD and sarcopenia, identified using the skeletal muscle index at the third lumbar vertebra level (L3-SMI). Methods: Hospitalized patients with ARLD were retrospectively enrolled between 2015 and 2018 and followed up for 24 months to evaluate their survival profiles. Cox proportional hazards regression models were used to estimate patient survival factors. A receiver operating characteristic curve was created to identify the cut-off point of the L3-SMI for predicting the prognoses of Chinese patients with ARLD. Results: The study enrolled 168 male patients with ARLD who were followed-up for 24 months or until a study endpoint was met. The overall L3-SMI in patients with ARLD was 42.61 ± 9.15 cm2/m2, and 42.86% (72/168) of patients with ARLD were comorbid with sarcopenia. The overall survival in patients with ARLD was 77.38% at 24 months. The survival rate of patients with sarcopenia was lower than that of patients without sarcopenia (66.67% vs. 85.42%, p = 0.004). Multiple Cox regression analysis showed that sarcopenia, abstinence, and baseline creatinine level were independent prognostic factors of 24-month survival with hazard ratios (95% confidence intervals) of 2.022 (1.025-3.991), 0.275 (0.122-0.617), and 1.018 (1.008-1.027), respectively. The cut-off value of the L3-SMI for predicting 24-month survival was 40.0 cm2/m2 for male patients with ARLD. Conclusion: Sarcopenia is an independent mortality risk factor in male patients with ARLD in mainland China. Early diagnosis and intervention of sarcopenia are important for optimizing the management of patients with ARLD.
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Coronavirus disease 2019 (COVID-19) has ravaged the world since December 2019. Up to now, it is still prevalent around the world. Vaccines are an important means to prevent the spread of COVID-19 and reduce severe disease and mortality. Currently, different types of novel coronavirus vaccines are still being developed and improved, and the relevant vaccines that have been approved for marketing have been widely vaccinated around the world. As vaccination coverage continues to grow, concerns about the efficacy and safety of vaccines after real-world use have grown. Some clinical studies have shown that vaccine effectiveness is closely related to antibody response after vaccination. Among them, the advantages of COVID-19 messenger ribonucleic acid (mRNA) vaccine, such as better adaptability to variant strains and better immune response ability, have attracted great attention. However, different populations with different genders, ages, previous COVID-19 infection history, underlying diseases and treatments will show different antibody responses after mRNA vaccination, which will affect the protection of the vaccine. Based on this, this paper reviews the reports related severe acute respiratory syndrome Coronavirus 2 mRNA vaccines, and summarizes the effectiveness of vaccines in different populations and different disease states and looked forward to the precise vaccination strategy of the vaccine in the future.
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Vacinas contra COVID-19 , COVID-19 , Feminino , Masculino , Humanos , SARS-CoV-2 , COVID-19/prevenção & controle , RNA Mensageiro , Vacinas de mRNARESUMO
Background: The raising trend of cultivation of Bacillus thuringiensis (Bt)-transgenic cotton is faced with a new challenge what effects on the growth and yield of Bt cotton under elevated CO2. Methods: Rhizobacteria is the significant biological regulator to increase environmental suitability and ameliorate soil-nitrogen utilization efficiency of crops, especially Bt cotton. Pot-culture experiments investigated the effects on the yield and fiber quality components of Bt cotton (transgenic Line SCRC 37) inoculated with Azotobacter chroococcum (AC) under elevated CO2. Results: The findings indicated that the inoculation of azotobacter significantly improved the yield and fiber quality components of Bt cotton, the elevated CO2 significantly increased the soil density of A. chroococcum and the partial yield indexes (as cottonweightper 20 bolls, lint yield per 20 bolls and boll number per plant), and non-significant decrease the fiber quality components of Bt cotton except uniform. Discussion: Overall results obviously depicted that the inoculation of azotobacter and the elevated CO2 had positive effects on the yield and fiber quality components of Bt cotton. Presumably, azotobacter inoculation can be used to stimulate plant soil-nitrogen uptake and promote plant growth for Bt cotton under elevated CO2 in the future.
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Azotobacter , Bacillus thuringiensis , Dióxido de Carbono , Azotobacter/genética , Solo , Gossypium/genética , NitrogênioRESUMO
Baclofen is the only drug that has been investigated in randomized controlled studies for anti-craving in patients with alcohol use disorder (AUD) and liver disease. However, the results of its efficacy are controversial due to limited case numbers; therefore, a meta-analysis of all available studies is needed to verify efficacy and safety in this population. This systematic review and meta-analysis were conducted according to the Cochrane Collaboration Handbook (PROSPERO ID: CRD42021284439) clauses. PubMed, Embase, Medline, Cochrane, and Clinical Trials. Gov were searched for patients with AUD co-morbid liver diseases who used baclofen to maintain abstinence. The primary outcome was maintaining abstinence. Baclofen safety was evaluated by adverse reaction occurrence during treatment. A total of 322 patients with AUD co-morbid liver diseases (alcohol-related liver disease, hepatitis C, or cirrhosis) from five studies were included. The total abstinence rate was 53% (95% CI: 0.23-0.84). Specifically, the abstinence rate in patients with alcohol-related liver disease and cirrhosis was 63% and 55%, respectively. We further analyzed the two included randomized controlled studies to compare the efficacy between baclofen and a placebo. There was no significant difference in abstinence rates between baclofen and the placebo (RR: 1.42, 95% CI: 0.41-4.92). One serious adverse event was reported, and no cases of baclofen addiction were found. The abstinence rate in patients with AUD co-morbid liver diseases was 53%; however, the efficacy of baclofen for maintaining abstinence in this population still needs to be validated with further studies.
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Alcoolismo , Hepatopatias , Humanos , Alcoolismo/complicações , Alcoolismo/tratamento farmacológico , Baclofeno/efeitos adversos , Consumo de Bebidas Alcoólicas , Hepatopatias/complicações , Hepatopatias/tratamento farmacológico , FissuraRESUMO
Tree species recognition accuracy greatly affects forest remote sensing mapping and forestry resource monitoring. The multispectral and texture features of the remote sensing images from the ZiYuan-3 (ZY-3) satellite at two phenological phases of autumn and winter (September 29th and December 7th) were selected for constructing and optimizing sensitive spectral indices and texture indices. Multidimensional cloud model and support vector machine (SVM) model were constructed by the screened spectral and texture indices for remote sensing recognition of Quercus acutissima (Q. acutissima) and Robinia pseudoacacia (R. pseudoacacia) on Mount Tai. The results showed that, the correlation intensities of the constructed spectral indices with tree species were preferable in winter than in autumn. The spectral indices constructed by band 4 showed the superior correlation compared with other bands, both in the autumn and winter time phases. The optimal sensitive texture indices for both phases were mean, homogeneity and contrast for Q. acutissima, and contrast, dissimilarity and second moment for R. pseudoacacia. Spectral features were found to have a higher recognition accuracy than textural features for recognizing on both Q. acutissima and R. pseudoacacia, and winter showing superior recognition accuracy than autumn, especially for Q. acutissima. The recognition accuracy of the multidimensional cloud model (89.98%) does not show a superior advantage over the one-dimensional cloud model (90.57%). The highest recognition accuracy derived from a three-dimensional SVM was 84.86%, which was lower than the cloud model (89.98%) in the same dimension. This study is expected to provide technical support for the precise recognition and forestry management on Mount Tai.
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Quercus , Árvores , Máquina de Vetores de Suporte , Florestas , Agricultura FlorestalRESUMO
Establishing the remote sensing yield estimation model of wheat-maize rotation cultivated land can timely and accurately estimate the comprehensive grain yield. Taking the winter wheat-summer maize rotation cultivated land in Caoxian County, Shandong Province, as test object, using the Sentinel-2 images from 2018 to 2019, we compared the time-series feature classification based on QGIS platform and support vector machine algorithm to select the best method and extract sowing area of wheat-maize rotation cultivated land. Based on the correlation between wheat and maize vegetation index and the statistical yield, we screened the sensitive vegetation indices and their growth period, and obtained the vegetation index integral value of the sensitive spectral period by using the Newton-trapezoid integration method. We constructed the multiple linear regression and three machine learning (random forest, RF; neural network model, BP; support vector machine model, SVM) models based on the integral value combination to get the best and and optimized yield estimation model. The results showed that the accuracy rate of extracting wheat and maize sowing area based on time-series features using QGIS platform reached 94.6%, with the overall accuracy and Kappa coefficient were 5.9% and 0.12 higher than those of the support vector machine algorithm, respectively. The remote sensing yield estimation in sensitive spectral period was better than that in single growth period. The normalized differential vegetation index and ratio vegetation index integral group of wheat and enhanced vegetation index and structure intensify pigment vegetable index integral group of maize could more effectively aggregate spectral information. The optimal combination of vegetation index integral was difference, and the fitting accuracy of machine learning algorithm was higher than that of empirical statistical model. The optimal yield estimation model was the difference value group-random forest (DVG-RF) model of machine learning algorithm (R2=0.843, root mean square error=2.822 kg·hm-2), with a yield estimation accuracy of 93.4%. We explored the use of QGIS platform to extract the sowing area, and carried out a systematical case study on grain yield estimation method of wheat-maize rotation cultivated land. The established multi-vegetation index integral combination model was effective and feasible, which could improve accuracy and efficiency of yield estimation.
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Triticum , Zea mays , Tecnologia de Sensoriamento Remoto/métodos , Grão Comestível , ChinaRESUMO
BACKGROUND: Hepatic myelopathy (HM) is a rare neurological complication of advanced cirrhosis. Prognosis of patients with HM is generally poor without timely liver transplantation or interventional therapy. Self-resolving HM in patients with alcoholic cirrhosis has never been reported. CASE SUMMARY: A 53-year-old man with alcoholic cirrhosis and recurrent overt hepatic encephalopathy for 1 year was admitted for lower extremity weakness, slow movement, and stumbling gait. The patient was diagnosed with HM after excluding other causes of spastic paraparesis. The patient refused liver transplantation. However, the patient kept total abstinence and received a multidisciplinary treatment for complications of decompensated cirrhosis. The symptoms of HM resolved gradually after 2 years of treatment. All complications of alcoholic cirrhosis resolved after 4 years of follow-up. CONCLUSION: The case demonstrates that HM can resolve in patients without liver transplan-tation after total abstinence and systemic management of complications.
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Imipenem cilastatin sodium, as a member of a new generation of ß-lactam antibiotics, has a broad spectrum of antibacterial activity and a very wide range of application. Thrombocytopenia has been reported as a rare adverse event in several studies of patients treated with imipenem cilastatin sodium. In this study, we present a case of thrombocytopenia associated with imipenem cilastatin sodium in an older patient. The 78-year-old male patient with pulmonary infection was initiated on anti-infection therapy with imipenem cilastatin sodium. On the 9th day after imipenem cilastatin sodium administration, the patient experienced a sudden and dramatic decrease in platelet count. Similarly, on the 4th day after the re-administration of imipenem cilastatin sodium for anti-infection therapy, the patient's platelet count showed a remarkable downward trend again. A time correlation between the drug therapy and the occurrence of platelet reaction was found. The patient's platelet count gradually returned to the normal level on the 6th day after the first drug withdrawal and the 13th day after the second drug withdrawal, respectively. Considering the widespread use of imipenem cilastatin sodium, healthcare providers should improve the notification of thrombocytopenia associated with imipenem cilastatin sodium.
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Infecções Bacterianas , Trombocitopenia , Idoso , Antibacterianos/efeitos adversos , Infecções Bacterianas/tratamento farmacológico , Cilastatina/efeitos adversos , Combinação Imipenem e Cilastatina/uso terapêutico , Combinação de Medicamentos , Humanos , Imipenem/efeitos adversos , Masculino , Tienamicinas/uso terapêutico , Trombocitopenia/induzido quimicamente , Trombocitopenia/diagnóstico , Trombocitopenia/tratamento farmacológicoRESUMO
Transmission rate and role in hosts contribute to the prevalence of an endosymbiont. However, factors affecting transmission and role of facultative endosymbionts are still not well understood. Here, we illustrated that host plants and environmental temperatures affected the transmission, relative abundance and role of Arsenophonus in the cotton aphid Aphis gossypii. The transmission rate of this endosymbiont from mother aphids to offspring was relatively lower. High temperatures impeded the transmission, and infection rates declined as aphids were exposed to 30°C. Contents of amino acids and secondary metabolites were remarkably different among host plants. Aphids feeding on zucchini leaves containing a higher titre of amino acids and lower secondary metabolites harboured a relatively lower abundance of Arsenophonus. Concentrations of an amino acid and a plant secondary metabolite, cucurbitacin B, in aphid diet were not associated with Arsenophonus abundance. However, gossypol, another plant secondary metabolite, was strongly related with the abundance. Arsenophonus imparted a fitness benefit to aphids, and the benefit was dependent on host plants and gossypol concentration. In sum, plant secondary metabolite and environmental temperature affect transmission, relative abundance and role of Arsenophonus, which determine the endosymbiont prevalence in aphid populations.
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Afídeos , Gammaproteobacteria , Gossipol , Aminoácidos , Animais , Plantas , Prevalência , Simbiose , TemperaturaRESUMO
Monitoring salinity information of salinized soil efficiently and precisely using the unmanned aerial vehicle (UAV) is critical for the rational use and sustainable development of arable land resources. The sensitive parameter and a precise retrieval method of soil salinity, however, remain unknown. This study strived to explore the sensitive parameter and construct an optimal method for retrieving soil salinity. The UAV-borne multispectral image in China's Yellow River Delta was acquired to extract band reflectance, compute vegetation indexes and soil salinity indexes. Soil samples collected from 120 different study sites were used for laboratory salt content measurements. Grey correlation analysis and Pearson correlation coefficient methods were employed to screen sensitive band reflectance and indexes. A new soil salinity retrieval index (SSRI) was then proposed based on the screened sensitive reflectance. The Partial Least Squares Regression (PLSR), Multivariable Linear Regression (MLR), Back Propagation Neural Network (BPNN), Support Vector Machine (SVM), and Random Forest (RF) methods were employed to construct retrieval models based on the sensitive indexes. The results found that green, red, and near-infrared (NIR) bands were sensitive to soil salinity, which can be used to build SSRI. The SSRI-based RF method was the optimal method for accurately retrieving the soil salinity. Its modeling determination coefficient (R2) and Root Mean Square Error (RMSE) were 0.724 and 1.764, respectively; and the validation R2, RMSE, and Residual Predictive Deviation (RPD) were 0.745, 1.879, and 2.211.
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Salinidade , Solo , China , Rios , Dispositivos Aéreos não TripuladosRESUMO
Tigecycline is a tetracycline-class antibacterial indicated for the treatment of complicated skin and skin-structure infections, complicated intra-abdominal infections, and community-acquired bacterial pneumonia. It has a broad-spectrum antibacterial activity. It has identified gastrointestinal side-effects, particularly nausea and vomiting. With the increasing clinical use of tigecycline, its associated acute pancreatitis has been frequently reported in adults. However, cases of tigecycline-induced acute pancreatitis have rarely been described in children. In this study, we report a case of acute pancreatitis caused by the use of tigecycline in a child with pulmonary cystic fibrosis. In this case, abdominal pain, nausea, and vomiting occurred on the 5th day after the use of tigecycline. Elevated pancreatic enzymes occurred, and abdominal computed tomography findings were compatible with pancreatitis. After 2 weeks of discontinuation of tigecycline, the pancreatic enzyme level decreased to normal, and the symptoms of abdominal pain, nausea, and vomiting disappeared completely. In conclusion, we hope to improve the clinical awareness of children with tigecycline-associated pancreatitis, so as to reduce the probability of adverse reactions through the analysis of this case.
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Fibrose Cística , Pancreatite , Doença Aguda , Adulto , Antibacterianos/efeitos adversos , Criança , Fibrose Cística/tratamento farmacológico , Humanos , Minociclina/efeitos adversos , Pancreatite/induzido quimicamente , Pancreatite/diagnóstico , Pancreatite/tratamento farmacológico , TigeciclinaRESUMO
Objectives: Alcohol-related liver disease is an increasing public health burden in China, but there is a lack of models to predict its prognosis. This study established a nomogram for predicting the survival of Chinese patients with alcohol-related liver disease (ALD). Methods: Hospitalized alcohol-related liver disease patients were retrospectively enrolled from 2015 to 2018 and followed up for 24 months to evaluate survival profiles. A total of 379 patients were divided into a training cohort (n = 265) and validation cohort (n = 114). Cox proportional hazard survival analysis identified survival factors of the patients in the training cohort. A nomogram was built and internally validated. Results: The 3-month, 6-month, 12-month, and 24-month survival rates for the training cohort were 82.6%, 81.1%, 74.3%, and 64.5%, respectively. The Cox analysis showed relapse (P=0.001), cirrhosis (P=0.044), liver cancer (P < 0.001), and a model for end-stage liver diseases score of ≥21 (P=0.041) as independent prognostic factors. A nomogram was built, which predicted the survival of patients in the training cohort with a concordance index of 0.749 and in the internal validation cohort with a concordance index of 0.756. Conclusion: The long-term survival of Chinese alcohol-related liver disease patients was poor with a 24-month survival rate of 64.5%. Relapse, cirrhosis, liver cancer, and a model for end-stage liver disease score of ≥21 were independent risk factors for those patients. A nomogram was developed and internally validated for predicting the probability of their survival at different time points.
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Doença Hepática Terminal , Nomogramas , China/epidemiologia , Humanos , Recidiva Local de Neoplasia , Prognóstico , Estudos Retrospectivos , Índice de Gravidade de DoençaRESUMO
Agrometallomics, as an independent interdiscipline, is first defined and described in this review. Metallic elements widely exist in agricultural plants, animals and edible fungi, seed, fertilizer, pesticide, feedstuff, as well as the agricultural environment and ecology, and even functional and pathogenic microorganisms. So, the agrometallome plays a vital role in molecular and organismic mechanisms like environmetallomics, metabolomics, proteomics, lipidomics, glycomics, immunomics, genomics, etc. To further reveal the inner and mutual mechanism of the agrometallome, comprehensive and systematic methodologies for the analysis of beneficial and toxic metals are indispensable to investigate elemental existence, concentration, distribution, speciation, and forms in agricultural lives and media. Based on agrometallomics, this review summarizes and discusses the advanced technical progress and future perspectives of metallic analytical approaches, which are categorized into ultrasensitive and high-throughput analysis, elemental speciation and state analysis, and spatial- and microanalysis. Furthermore, the progress of agrometallomic innovativeness greatly depends on the innovative development of modern metallic analysis approaches including, but not limited to, high sensitivity, elemental coverage, and anti-interference; high-resolution isotopic analysis; solid sampling and nondestructive analysis; metal chemical species and metal forms, associated molecular clusters, and macromolecular complexes analysis; and metal-related particles or metal within the microsize and even single cell or subcellular analysis.
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Metabolômica , Metais , Animais , Espectrometria de Massas , Plantas , ProteômicaRESUMO
The ecological environment of the Yellow River Delta is fragile, and the soil degradation in the region is serious. Therefore it is important to discern the status of the soil degradation in a timely manner for soil conservation and utilization. The study area of this study was Kenli County in the Yellow River Delta of China. First, physical and chemical data of the soil were obtained by field investigations and soil sample analyses, and the hyper-spectra of air-dried soil samples were obtained via spectrometer. Then, the soil degradation index (SDI) was constructed by the key indicators of soil degradation, including pH, SSC, OM, AN, AP, AK, and soil texture. Next, according to a cluster analysis, soil degradation was divided into the following three grades: light degradation, moderate degradation, and heavy degradation. Moreover, the spectral characteristics of soil degradation were analyzed, and an estimation model of SDI was established by multiple stepwise regression. The results showed that the overall level of reflectance spectra increased with increased degree of soil degradation, that both derivative transformation and waveband reorganization could enhance the spectral information of soil degradation, and that the correlation between SDI and the spectral parameter of (Rλ2+Rλ1)/(Rλ2-Rλ1) was the highest among all the spectral parameters studied. On this basis, the optimum estimation model of SDI was established with the correlation coefficient of 0.811. This study fully embodies the potential of hyper-spectral technology in the study of soil degradation and provides a technical reference for the rapid extraction of information from soil degradation. Additionally, the study area is typical and representative, and thus can indirectly reflect the soil degradation situation of the whole Yellow River Delta.
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Monitoramento Ambiental/métodos , Solo/química , Análise Espectral/métodos , China , Análise por Conglomerados , Monitoramento Ambiental/estatística & dados numéricos , Concentração de Íons de Hidrogênio , Modelos Teóricos , Nitrogênio/análise , Nitrogênio/química , Fósforo/análise , Fósforo/química , Potássio/análise , Potássio/químicaRESUMO
BACKGROUND: A polyphagous insect herbivore has a wide range of host plants. However, it has been found that many polyphagous herbivores commonly exhibit a strong preference for a subset of species in their broad host range, and various host biotypes exist in herbivore populations. Nutrition and secondary metabolites in plants affect herbivore preference and performance, but it is still not clear which factors determine the host range and host preference of polyphagous herbivores. METHOD: Cotton-melon aphids, Aphis gossypii Glover, collected from cotton and cucumber crops, were used in this study. The genetic backgrounds of these aphids were detected using microsatellite PCR and six genotypes were evaluated. Performance of these six aphid genotypes on excised leaves and plants of cotton and cucumber seedlings were examined through a reciprocal transplant experiment. In order to detect whether the feeding experience on artificial diet would alter aphid host range, the six genotypes of aphids fed on artificial diet for seven days were transferred onto cotton and cucumber leaves, and then their population growth on these two host plants was surveyed. RESULTS: Aphids from cotton and cucumber plants could not colonize the excised leaves and intact plants of cucumber and cotton seedlings, respectively. All six genotypes of aphids collected from cotton and cucumber plants could survive and produce offspring on artificial diet, which lacked plant secondary metabolites. The feeding experience on the artificial diet did not alter the ability of all six genotypes to use their native host plants. However, after feeding on this artificial diet for seven days, two aphid genotypes from cotton and one from cucumber acquired the ability to use both of the excised leaves from cucumber and cotton plants. The two aphid genotypes from cotton conditioned by the feeding experience on artificial diet and then reared on excised cucumber leaves for >12 generations still maintained the ability to use intact cotton plants but did not establish a population on cucumber plants. However, one cucumber genotype conditioned by artificial diet and then reared on excised cotton leaves could use both the intact cotton and cucumber plants, showing that the expansion of host range was mediated by feeding experience. CONCLUSION: Feeding experience on artificial diet induced the expansion of host range of the cucurbit-specialized A. gossypii, and this expansion was genotype-specific. We speculated that feeding on a constant set of host plants in the life cycle of aphids may contribute to the formation of host specialization.
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Genetic polymorphism and endosymbiont infection are ubiquitous in aphid populations. It has been known that the obligate symbiont Buchnera provides aphids with essential amino acids which cannot be ingested from plant sap. Buchnera often coexists with facultative endosymbionts in aphids. However, it is unclear whether the facultative endosymbionts affect the aphid's amino acid requirements from diet. In this study, we found that the facultative endosymbiont status in populations of the cotton-melon aphid Aphis gossypii was associated with aphid genotype or host plant. The infection frequency of Arsenophonus in aphids living on cotton was significantly higher than that in aphids on cucumber, and cucumber leaves contained higher titers of free amino acids than cotton leaves, especially amino acids Leu, Arg, Ile, Val, and Phe. The net reproductive rates of five aphid genotypes infected with Arsenophonus were not different on the complete-amino-acid diet, but the values were significantly different among seven Arsenophonus-free aphid genotypes. Moreover, the net reproductive rates of aphids on the amino-acid-deficient diet were significantly affected by Arsenophonus infection and aphid genotype. Arsenophonus infection decreased aphid performance on the Phe-free diet but improved performance on the Leu-free diet and did not affect the performance on the Ile-free or Val-free diet. Arsenophonus infections altered aphid requirements for amino acids that were significantly different in cotton and cucumber leaves, suggesting this endosymbiont would modulate the host specialization of this aphid.IMPORTANCE The facultative endosymbiont Arsenophonus plays an important role in regulating reproduction through son killing, enemy resistance, and the dietary breadth of its insect hosts. In this study, we found Arsenophonus could alter aphid performance on the amino-acid-deficient diets. Arsenophonus infection increased aphid requirements for the amino acid Phe, but decreased requirements for the Leu. Cotton and cucumber leaves contained drastically different titers of free amino acids Phe and Leu, and aphids living on these two plants were infected with different incidences of Arsenophonus We hypothesize that host specialization or the host plant range of aphids may be mediated by Arsenophonus.
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Afídeos/microbiologia , Cadeia Alimentar , Gammaproteobacteria/fisiologia , Simbiose , Aminoácidos/deficiência , Animais , Afídeos/crescimento & desenvolvimento , Cucumis sativus , Gossypium , Ninfa/crescimento & desenvolvimento , Ninfa/microbiologiaRESUMO
The aberrant assembly of microtubule-associated protein Tau (τ) into insoluble aggregates is closely related to Alzheimer's disease (AD), which is elicited from Tau phosphorylation events and regulated by the specific intermolecular recognition between the proline-rich PxxP motifs of Tau and the SH3 domains of its diverse partner proteins/kinases. Here, we attempt to create a systematic interaction profile for the 10 SH3 domains of previously reported Tau partners across all the 18 Tau PxxP peptides. A number of biologically functional SH3-PxxP interaction events are identified from the profile and then tested using fluorescence spectroscopy. It is revealed that (i) the region (residues 520-560) precedent to the tubulin-binding partial repeats of Tau protein is an important target of SH3 domains, where contains the three PxxP peptides τp527-536, τp530-539 and τp547-556 that exhibit different binding profiles towards the investigated SH3 domains, (ii) as compared to τp527-536 and τp547-556, the τp530-539 peptide located between them has only a modest binding potency to most SH3 domains, suggesting that the three peptides contribute unevenly to Tau-SH3 interactions, and (iii) some other Tau PxxP peptides, particularly those within the residue range 490-510 that is neighboring to the region 520-560, can also interact effectively with several SH3 domains. The SH3 domain of the well known Tau partner kinase Fyn is determined to have high or moderate affinity for an array of Tau PxxP peptides, including τp137-146, τp493-502, τp527-536 and τp547-556 (Kd ranges 15.7-85.6⯵M).
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Doença de Alzheimer/metabolismo , Mapas de Interação de Proteínas/fisiologia , Domínios de Homologia de src/fisiologia , Proteínas tau/metabolismo , Simulação por Computador , Humanos , Peptídeos/metabolismo , Fosforilação/fisiologia , Ligação Proteica/fisiologia , Tubulina (Proteína)/metabolismoRESUMO
The remote sensing technology provides a new means for the determination of chlorophyll content in apple trees that includes a rapid analysis, low cost and large monitoring area. The Back-Propagation Neural Network (BPNN) and the Supported Vector Machine Regression (SVMR) methods were both frequently used method to construct estimation model based on remote sensing imaging. The aim of this study was to find out which estimation model of apple tree canopy chlorophyll content based on the vegetation indices constructed with visible, red edge and near-infrared bands of the sensor of Sentinel-2 was more accurate and stabler. The results were as follows: The calibration set coefficient of determination (R2) value of 0.729 and validation set R2 value of 0.667 of the model using the SVMR method based on the vegetation indices (NDVIgreen + NDVIred + NDVIre) were higher than those of the model using the BPNN method by 8.2% and 11.0%, respectively. The calibration set root mean square error (RMSE) of 0.159 and validation set RMSE of 0.178 of the model using the SVMR method based on the vegetation indices (NDVIgreen + NDVIred + NDVIre) were lower than those of the model using the BPNN method by 5.9% and 3.8%, respectively.