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1.
Plant Dis ; 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34752122

RESUMO

In June 2018 and 2019, charcoal rot-like symptoms and black microsclerotia suggestive of Macrophomina phaseolina infection were observed on the basal stems of citrullus lanatus cv. 'Zaojia', causing premature death. About 1 hectare of 'Zaojia' had been investigated, disease incidence rates were almost 50%, resulting in a 40% yield loss in a single field in Shanghai, China (31°23'N , 121°33'E). A fungus was consistently isolated from infected watermelon tissues. In total, 30 cuttings from 10 infected seedlings were surface disinfected with 3% sodium hypochlorite for 3 min, washed thrice with sterile distilled water, air dried, and transferred onto potato dextrose agar (PDA). Dishes were incubated for 3 days at 27°C in the dark. Twenty four single hypha subcultures were obtained from these samples and were cultured for an additional 5 days at 27°C. Colonies were initially white, and then became grey black (Fig.1A). During the more advanced stages of infection, black microsclerotia were produced that were spherical or ovoid in shape (Fig.1B). No sexual structures and conidia developed during culture on PDA. Isolate pathogenicity was assessed both in vitro and in vivo. Watermelon plants (cv. 'Zaojia') were grown in growth chambers at 28°C (day) and 23°C (night), with a 16 h photoperiod. When seedlings were 20 days old, they were inoculated. Briefly, a needle was used to puncture watermelon stems, and 5 mm agar plugs containing actively growing mycelia were placed on these needle wounds, followed by culture for 72 h at 27°C in a dark, humid chamber. In total, 10 seedlings were inoculated with 5 mm blank PDA, and the experiment was repeated three times, with the treatment being perfomed as described above. Seedling stems were inoculated 1-2 cm above the ground by puncturing them with a needle and then transferring 5 mm agar plugs containing fungi onto the wound sites. Seedlings were kept 75% humidity and then grown for 5 days at 27°C. Ten seedlings were inoculated per experiment. As a control, 10 seedlings were inoculated with 5 mm blank PDA plugs. Experiments were repeated three times. Necrotic spots around the wounds were evident on inoculated stems at 72 h (Fig.1C). Similarly, vascular tissue necrosis and the collapse of the surrounding pith and epidermis were observed on the residual parts of seedling stems after 5 days (Fig.1E), whereas control stems did not exhibit any disease related symptoms (Fig.1D, 1F). The same pathogen was then successfully re-isolated and was successfully regrown in pure culture, thus fulfilling Koch's postulates. To identify the causative pathogen, total mycelial DNA was isolated via the CTAB method (Brandfass & Karlovsky, 2008), and the internal transcribed spacer (ITS) rDNA regions were amplified using the ITS1/ITS4 primers (White, 1990), the genus-specific MPKFI//span>MpKRI primers were used for further amplification (Babu et al., 2007). M. phaseolina ITS sequences in this study shared 100% similarity with the ITS sequences of M. phaseolina from Chickpea (MK757624.1). Genus-specific sequences from this isolate shared 100% homology with other M. phaseolina isolates (MT645816.1 and MN263167.1). As such, M. phaseolina was confirmed to be the pathogen responsible for watermelon charcoal rot in the present report, which resulted in the death of infected watermelons before maturity, causing fruits to lose their commodity value. This report is the first to our knowledge to identify M. phaseolina as a causal pathogen of watermelon charcoal rot in China.

2.
Chem Biol Interact ; 351: 109751, 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34826398

RESUMO

p-phenylenediamine (PPD) is a common component of hair dye known to induce immediate allergy, even acute dermatitis and contact dermatitis. MAS-related G protein coupled receptor-X2 (MRGPRX2) in mast cells (MCs) mediates small molecular substances-induced pseudo-allergic reactions. However, the role of MRGPRX2 in PPD-induced immediate contact allergy needs further exploration. The aim of this study was to investigate whether PPD activates MCs via MRGPRX2 and induces immediate allergies that contribute to contact dermatitis. Wild-type (WT) and kitw-sh/w-sh mice (MUT) were treated with PPD to observe local inflammation and MC degranulation in vivo. The release of inflammatory mediators was measured in vitro. Histamine 1 receptor (H1R)-/- mice were used to analyze itch type. PPD caused immediate contact allergy in WT mice, induced scratching, and local inflammatory reactions, while exhibiting minimal effects on MUT mice. PPD did not induce histamine release, but induced significant tryptase release in vivo and in vitro. PPD activated MRGPRX2 to induce MC degranulation in vitro. PPD caused immediate contact allergy in WT mice, induced scratching and local inflammatory reactions, while exhibited minimal effect on MUT mice. PPD did not induce histamine release, while induced significant tryptase release in vivo and in vitro. PPD induced immediate contact allergy by MCs activation via MRGPRX2 and lead to tryptase release. The scratching times showed no significant difference in WT mice or H1R-/- mice, which indicated PPD caused non-histaminergic itch. The results showed that PPD activated MCs via MRGPRX2 and induced immediate contact allergy, leading to the release of tryptase without monoamine release, which might induce non-histaminergic itch.

3.
Front Microbiol ; 12: 773992, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34803995

RESUMO

Recombination drives evolution of single-stranded RNA viruses and contributes to virus adaptation to new hosts and environmental conditions. Intraspecific recombinants are common in potyviruses, the largest family of single-stranded RNA viruses, whereas interspecific recombinants are rare. Here, we report an interspecific recombination event between papaya ringspot potyvirus (PRSV) and zucchini tigre mosaic potyvirus (ZTMV), two potyviruses infecting cucurbit crops and sharing similar biological characteristics and close phylogenetic relationship. The PRSV-ZTMV recombinants were detected through small RNA sequencing of viruses infecting cucurbit samples from Guangxi and Henan provinces of China. The complete nucleotide (nt) sequences of the interspecific recombinant viruses were determined using overlapping RT-PCR. Multiple sequence alignment, recombination detection analysis and phylogenetic analysis confirmed the interspecific recombination event, and revealed an additional intraspecific recombination event among ZTMV populations in China. The symptoms and host ranges of two interspecific recombinant isolates, KF8 and CX1, were determined through experimental characterization using cDNA infectious clones. Surveys in 2017 and 2018 indicated that the incidences of the interspecific recombinant virus were 16 and 19.4%, respectively, in cucurbits in Kaifeng of Henan province. The identified interspecific recombinant virus between PRSV and ZTMV and the novel recombination pattern with the recombination site in HC-pro in potyvirid provide insights into the prevalence and evolution of ZTMV and PRSV in cucurbits.

4.
SN Bus Econ ; 1(4): 54, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34778826

RESUMO

This paper examines the effects of pandemics on income inequality, specifically those pandemics that claimed more than 100,000 lives. Given that pandemics are events that rarely occur, we have use data spanning over the last 100 years (1915-2017) and relating to four pandemics. The study includes four countries that had income inequality data covering that period. Using panel data methods-fixed effects and augmented mean group estimators-we found a significant effect of these pandemics on declining income inequality. The study argues that based on the characteristics of the COVID-19 pandemic, namely that fatalities are highly concentrated in older age groups, we can neither expect a labor scarcity nor a sharp decline in productivity; however, we could expect a reduction in consumption, the possibility of savings, high unemployment rates, and high public debt ratios. The ultimate effects of COVID-19 on inequality remain unclear so far, as some of its inherent characteristics push for an increase in inequality. In contrast, others push toward a narrowing of the income gap. Supplementary Information: The online version contains supplementary material available at 10.1007/s43546-021-00059-4.

5.
Neurol Neurochir Pol ; 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34783353

RESUMO

INTRODUCTION: Different categories of hospitals in China have varying levels of patient education. Stroke recognition and emergency medical services (EMS) usage in patients appears to be closely associated with patient education in hospital. This study aimed to explore the effect of hospital classification in China on a patient's ability to recognise stroke symptoms and the likelihood of using the EMS. MATERIAL AND METHODS: A cross-sectional, community-based study was conducted from January to May 2017, and 1,426 residents who had previously been hospitalised were analysed. The patients involved in the study were from 69 administrative areas in China. Multivariable logistic regression models were developed separately for primary, secondary, and tertiary hospitals to identify the associations between hospital grades and patient stroke recognition or the prospects of them using the EMS. RESULTS: Among the 1,426 patients studied, 725 had been admitted to tertiary hospitals, 448 to secondary hospitals, and 253 to primary hospitals. According to univariate analysis, tertiary hospital patients were more likely to use the EMS than patients in primary and secondary hospitals. The difference therein was still significant after full adjustment. CONCLUSIONS: Patients in tertiary hospitals were significantly more likely to use the EMS promptly compared to patients in primary or secondary hospitals. Therefore, patient education on timely EMS usage at stroke onset should be enhanced in primary and secondary hospitals in China.

6.
J Am Heart Assoc ; 10(22): e021545, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34755547

RESUMO

Background Evidence of the association between serum lipid profiles and intraplaque neovascularization (IPN) is still limited. We aimed to study the value of a novel Doppler method, superb microvascular imaging, in correlating serum lipid profiles and evidence of IPN in a population with a high risk of stroke. Methods and Results A community-based cross-sectional study was conducted in Beijing, China. Residents (aged ≥40 years) underwent questionnaire interviews, physical examinations, and laboratory testing in 2018 and 2019. Subjects with a high risk of stroke were then selected. Standard carotid ultrasound and carotid plaque superb microvascular imaging examinations were then performed on the high-stroke-risk participants. Logistic regression was used to evaluate the relationship between serum lipid profiles and carotid plaque IPN. Overall, a total of 250 individuals (mean age, 67.20±8.12 years; 66.4% men) met the study inclusion criteria. Superb microvascular imaging revealed carotid plaque IPN in 96 subjects (38.4%). Subjects with IPN were more likely to be current smokers (34.0% versus 46.9%, P=0.046), and their identified carotid plaques were much thicker (2.35±0.63 mm versus 2.75±0.80 mm, P=0.001). Serum lipids, including total cholesterol, non-high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol were positively associated with the presence of IPN (4.33±1.00 mmol/L versus 4.79±1.12 mmol/L, P=0.001; 2.96±0.92 mmol/L versus 3.40±1.01 mmol/L, P=0.001; 2.18±0.76 mmol/L versus 2.46±0.80 mmol/L, P=0.005, respectively), and after adjustment for other confounders, the positive relationship remained significant. Furthermore, non-high-density lipoprotein cholesterol (odds ratio, 2.62 [95% CI, 1.35-5.06]) was significantly associated with the presence of carotid plaque IPN even after adjusting for low-density lipoprotein cholesterol. Conclusions Total cholesterol, non-high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol were positively associated with the presence of carotid IPN in a Chinese high-stroke-risk population. Further prospective studies should be conducted to better understand how much finding IPN adds to current stroke prediction tools.

7.
J Healthc Eng ; 2021: 8585887, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34840705

RESUMO

The goal of this study was to see if automatic biopsy guided by ultrasound could be used to provide a qualitative diagnosis of a liver tumor. Methods. A total of 40 patients (101 focuses) were treated with automatic liver parenchyma biopsy under ultrasound guidance, and the correlation between pathological outcomes and ultrasound images was investigated. The lesion size in the observation group was compared to that in the control group using conventional ultrasound (P > 0.05), and there was no significant difference. Under contrast-enhanced ultrasound (CEUS), there was no statistically significant difference in lesion size between the observation and control groups (P > 0.05). The difference in lesion size between the conventional ultrasonography and CEUS observation groups was statistically significant (P 0.05). Conclusion. Ultrasound-guided automated biopsy of the liver parenchyma is a simple and effective procedure with fewer problems and a high diagnostic rate, and it deserves to be promoted clinically.

9.
BMC Endocr Disord ; 21(1): 211, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34686184

RESUMO

BACKGROUND: Impaired fasting glucose (IFG) is a prediabetic condition. Considering that the clinical symptoms of IFG are inconspicuous, these tend to be easily ignored by individuals, leading to conversion to diabetes mellitus (DM). In this study, we established a prediction model for the onset risk of IFG in the Chongqing health check-up population to provide a reference for prevention in a health check-up cohort. METHODS: We conducted a retrospective longitudinal cohort study in Chongqing, China from January 2009 to December 2019. The qualified subjects were more than 20 years old and had more than two health check-ups. After following the inclusion and exclusion criteria, the cohort population was randomly divided into a training set and a test set at a ratio of 7:3. We first selected the predictor variables through the univariate generalized estimation equation (GEE), and then the training set was used to establish the IFG risk model based on multivariate GEE. Finally, the sensitivity, specificity, and receiver operating characteristic curves were used to verify the performance of the model. RESULTS: A total of 4,926 subjects were included in this study, with an average of 3.87 check-up records, including 2,634 males and 2,292 females. There were 442 IFG cases during the follow-up period, including 286 men and 156 women. The incidence density was 26.88/1000 person-years for men and 18.53/1000 person-years for women (P<0.001). The predictor variables of our prediction model include male (relative risk (RR) =1.422, 95 % confidence interval (CI): 0.923-2.193, P=0.3849), age (RR=1.030, 95 %CI: 1.016-1.044, P<0.0001), waist circumference (RR=1.005, 95 %CI: 0.999-1.012, P=0.0975), systolic blood pressure (RR=1.004, 95 %CI: 0.993-1.016, P=0.4712), diastolic blood pressure (RR=1.023, 95 %CI: 1.005-1.041, P=0.0106), obesity (RR=1.797, 95 %CI: 1.126-2.867, P=0.0140), triglycerides (RR=1.107, 95 %CI: 0.943-1.299, P=0.2127), high-density lipoprotein cholesterol (RR=0.992, 95 %CI: 0.476-2.063, P=0.9818), low-density lipoprotein cholesterol (RR=1.793, 95 %CI: 1.085-2.963, P=0.0228), blood urea (RR=1.142, 95 %CI: 1.022-1.276, P=0.0192), serum uric acid (RR=1.004, 95 %CI: 1.002-1.005, P=0.0003), total cholesterol (RR=0.674, 95 %CI: 0.403-1.128, P=0.1331), and serum creatinine levels (RR=0.960, 95 %CI: 0.945-0.976, P<0.0001). The area under the receiver operating characteristic curve (AUC) in the training set was 0.740 (95 %CI: 0.712-0.768), and the AUC in the test set was 0.751 (95 %CI: 0.714-0.817). CONCLUSIONS: The prediction model for the onset risk of IFG had good predictive ability in the health check-up cohort.

10.
Biomed Res Int ; 2021: 9972011, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34692847

RESUMO

Background: Increasing evidence demonstrated that long noncoding RNA (lncRNA) could affect inflammatory tumor immune microenvironment by modulating gene expression and could be used as a biomarker for HBC-related hepatocellular carcinoma (HCC) but still needs further research. The aim of the present study was to determine an lncRNA signature for the diagnosis of HBV-related HCC. Methods: HBV-related HCC expression profiles (GSE55092, GSE19665, and GSE84402) were abstracted from the GEO (Gene Expression Omnibus) data resource, and R package limma and RobustRankAggreg were employed to identify common differentially expressed genes (DEGs). Using machine learning, optimal diagnostic lncRNA molecular markers for HBV-related HCC were identified. The expression of candidate lncRNAs was cross-validated in GSE121248, and an ROC (receiver operating characteristic) curve of lncRNA biomarkers was carried out. Additionally, a coexpression network and functional annotation was built, after which a PPI (protein-protein interaction) network along with module analysis were conducted with the Cytoscape open source software. Result: A total of 38 DElncRNAs and 543 DEmRNAs were identified with a fold change larger than 2.0 and a P value < 0.05. By machine learning, AL356056.2, AL445524.1, TRIM52-AS1, AC093642.1, EHMT2-AS1, AC003991.1, AC008040.1, LINC00844, and LINC01018 were screened out as optional diagnostic lncRNA biosignatures for HBV-related HCC. The AUC (areas under the curve) of the SVM (support vector machine) model and random forest model were 0.957 and 0.904, respectively, and the specificity and sensitivity were 95.7 and 100% and 94.3 and 86.5%, respectively. The results of functional enrichment analysis showed that the integrated coexpressed DEmRNAs shared common cascades in the p53 signaling pathway, retinol metabolism, PI3K-Akt signaling cascade, and chemical carcinogenesis. The integrated DEmRNA PPI network complex was found to be comprised of 87 nodes, and two vital modules with a high degree were selected with the MCODE app. Conclusion: The present study identified nine potential diagnostic biomarkers for HBV-related HCC, all of which could potentially modulated gene expression related to inflammatory conditions in the tumor immune microenvironment. The functional annotation of the target DEmRNAs yielded novel evidence in evaluating the precise functions of lncRNA in HBV-related HCC.

11.
Front Psychol ; 12: 701945, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34603130

RESUMO

The Coronavirus Disease 2019 (COVID-19) may affect mental health. There is little research about the influence of family function on the state anxiety of college students in the context of the global pandemic. The study aimed to clarify that generalized anxiety disorder (GAD) and trait anxiety had mediating effects in family function on the state anxiety of Chinese college students following the "stay-at-home" order during the outbreak of COVID-19. This cross-sectional study was conducted online with 1,039 respondents. We analyzed demographics, The State-Trait Anxiety Inventory (ST-AI) and Chinese Family Function Scale (FAD-18), Generalized Anxiety Disorder-7 (GAD-7), and used path analysis to discuss the influence of family function on state and trait anxiety. The results showed that female students' state and trait anxiety was higher than that of male students (P < 0.05). Medical students' state and trait anxiety was lower than that of literature students (P < 0.05). The GAD of the male was lower compared with the female. The score of family function has significant differences in gender, age, education, and region (P < 0.05). Gender, family function, state anxiety, trait anxiety, and GAD relate to others (r = 0.07∼0.85, p < 0.05). The results of fit indices for measurement invariance models showed that the impact of family function among GAD, state and trait anxiety across gender is significantly different (each step p < 0.05). GAD and trait anxiety had a complete meditating effect between family function and state anxiety (the proportion of standard indirect mediating effect was 24.94% in females and 36.79% in males). A healthy family function may alleviate GAD and anxiety of college students during the COVID-19 pandemic.

12.
Materials (Basel) ; 14(19)2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34640297

RESUMO

This study compared the effects of the sulfate dry-wet cycle on the properties of ordinary concrete and nano-TiO2-modified concrete, including the mass loss rate, ultrasonic wave velocity, compressive strength, and XRD characteristics. In addition, a series of compression simulations carried out using the PFC2D software are also presented for comparison. The results show the following: (1) with an increase in dry-wet cycles, the damage to the concrete gradually increased, and adding nano-TiO2 into ordinary concrete can improve the material's sulfate resistance; (2) after 50 sulfate dry-wet cycles, the mass loss rate of ordinary concrete was -3.744%, while that of nano-TiO2-modified concrete was -1.363%; (3) the compressive strength of ordinary concrete was reduced from 41.53 to 25.12 MPa (a reduction of 39.51%), but the compressive strength of nano-TiO2-modified concrete was reduced from 49.91 to 32.12 MPa (a reduction of 35.64%); (4) after a sulfate dry-wet cycle, the nano-TiO2-modified concrete surface produced white crystalline products, considered to be ettringite based on the XRD analysis; (5) when considering the peak stress and strain of the concrete samples, the numerical results agreed well with the test results, indicating the reliability of the method.

13.
Front Neurol ; 12: 707134, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34650504

RESUMO

Objective: This study aimed to better understand the clinical, electrophysiological, pathological features and prognosis of peripheral nerve involvements in primary immunoglobulin light-chain (AL) amyloidosis. Methods: We retrospectively reviewed the clinical data of eight AL amyloidosis patients with peripheral neuropathy as the initial presentation including clinical features, histopathological findings and treatment. Results: There were seven males and one female aged from 52 to 66 years. Initial symptoms included symmetrical lower extremity numbness, lower extremity pain and carpal tunnel syndrome. Seven patients suffered from severe pain and required pain management. Six patients had predominant autonomic dysfunction. Six patients had cardiac involvement, and one patient had renal involvement. Monoclonal proteins were found in all patients, with IgA λ in one, IgG λ in two, λ alone in three, κ alone in one and IgM κ in one. Sural nerve biopsies were performed in 7 cases, all of which showed amyloid deposition in the endoneurium (in the perivascular region in some cases), in addition to moderate to severe myelinated fiber loss with axonal degeneration. Six patients were treated with combined chemotherapy. In three patients who began chemotherapy earlier (6-10 months after onset), two achieved a hematological complete response, and one achieved a partial response. three patients who had delayed chemotherapy (36 months after onset) died between 5 and 12 months after diagnosis. Conclusion: Early recognition of AL amyloidosis with peripheral neuropathy as the initial symptom is very important. Nerve biopsy can help to make the diagnosis. Early diagnosis and chemotherapy are critical to achieve better outcomes.

14.
Am J Transl Res ; 13(9): 10562-10569, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34650727

RESUMO

OBJECTIVE: To evaluate the value of the non-predominant micropapillary and solid patterns in prognosis of lung adenocarcinoma. METHODS: Totally 422 patients diagnosed with stage IA lung adenocarcinomas were included, and all their slides were reviewed. We compared clinicopathological characteristics and survival outcomes between MP- & SD- (both micropapillary and solid component were absent), MP+/SD+ (either micropapillary or solid component was present, but the single or combined percentage of the MP and SD was not greater than 50%) and MPp/SDp (either micropapillary or solid or the combined percentage of these two components was great than 50%). RESULTS: Patients with MP- & SD- had smaller tumor size (P=0.012) and lower spread through air spaces rates (P<0.001). Patients with MP- & SD- had significantly better 5-year recurrence free survival than MP+/SD+ (91% versus 70%, P<0.001) and MPp/SDp (91% versus 56%, P<0.001). The difference of RFS between MP+/SD+ subgroup and MPp/SDp subgroup was not significant (P=0.177). In the multivariate analysis, patients with MP- & SD- had a better recurrence free survival than the other two groups (versus: MP+/SD+, HR, 3.198; 95% CI, 1.537-6.653; P=0.002; versus MPp/SDp: HR, 4.981; 95% CI, 2.266-10.950; P<0.001). CONCLUSIONS: The presence of micropapillary or solid patterns, even not predominant, was a risk factor for predicting poor recurrence free survival in very early stage lung adenocarcinoma.

15.
Nano Lett ; 21(19): 8111-8118, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34597054

RESUMO

Despite being promising, the clinical application of magnetic hyperthermia for brain cancer treatment is limited by the requirement of highly invasive intracranial injections. To overcome this limitation, here we report the development of gallic acid-coated magnetic nanoclovers (GA-MNCs), which allow not only for noninvasive delivery of magnetic hyperthermia but also for targeted delivery of systemic chemotherapy to brain tumors. GA-MNCs are composed of clover-shaped MNCs in the core, which can induce magnetic heat in high efficiency, and polymerized GA on the shell, which enables tumor vessel-targeting. We demonstrate that intravenous administration of GA-MNCs following alternating magnetic field exposure effectively inhibited brain cancer development and preferentially disrupted tumor vasculature, making it possible to efficiently deliver systemic chemotherapy for further improved efficacy. Due to the noninvasive nature and high efficiency in killing tumor cells and enhancing systemic drug delivery, GA-MNCs have the potential to be translated for improved treatment of brain cancer.


Assuntos
Neoplasias Encefálicas , Hipertermia Induzida , Nanopartículas de Magnetita , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Humanos , Hipertermia , Fenômenos Magnéticos
16.
Plant Cell Environ ; 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34664281

RESUMO

Traditional gas exchange measurements are cumbersome, which makes it difficult to capture variation in biochemical parameters, namely the maximum rate of carboxylation measured at a reference temperature (Vcmax25 ) and the maximum electron transport at a reference temperature (Jmax25 ), in response to growth temperature over time from days to weeks. Hyperspectral reflectance provides reliable measures of Vcmax25 and Jmax25 ; however, the capability of this method to capture biochemical acclimations of the two parameters to high growth temperature over time has not been demonstrated. In this study, Vcmax25 and Jmax25 were measured over multiple growth stages during two growing seasons for field-grown soybeans using both gas exchange techniques and leaf spectral reflectance under ambient and four elevated canopy temperature treatments (ambient+1.5, +3, +4.5, and +6°C). Spectral vegetation indices and machine learning methods were used to build predictive models for Vcmax25 and Jmax25 , based on the leaf reflectance. Results showed that these models yielded an R2 of 0.57-0.65 and 0.48-0.58 for Vcmax25 and Jmax25 , respectively. Hyperspectral reflectance captured biochemical acclimation of leaf photosynthesis to high temperature in the field, improving spatial and temporal resolution in the ability to assess the impact of future warming on crop productivity.

17.
J Nanobiotechnology ; 19(1): 273, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34496881

RESUMO

The control of contagious or refractory diseases requires early, rapid diagnostic assays that are simple, fast, and easy-to-use. Here, easy-to-implement CRISPR/Cas12a-based diagnostic platform through Raman transducer generated by Raman enhancement effect, term as SERS-CRISPR (S-CRISPR), are described. The S-CRISPR uses high-activity noble metallic nanoscopic materials to increase the sensitivity in the detection of nucleic acids, without amplification. This amplification-free platform, which can be performed within 30-40 min of incubation time, is then used for detection of SARS-CoV-2 derived nucleic acids in RNA extracts obtained from nasopharyngeal swab specimens (n = 112). Compared with the quantitative reverse transcription polymerase chain reaction (RT-qPCR), the sensitivity and specificity of S-CRISPR reaches 87.50% and 100%, respectively. In general, the S-CRISPR can rapidly identify the RNA of SARS-CoV-2 RNA without amplification and is a potential strategy for nucleic acid point of care test (POCT).


Assuntos
Sistemas CRISPR-Cas/genética , Técnicas de Amplificação de Ácido Nucleico , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Análise Espectral Raman , COVID-19/diagnóstico , COVID-19/virologia , Regulação Fúngica da Expressão Gênica , Genes Virais , Humanos , RNA Viral/análise , Sensibilidade e Especificidade
18.
PeerJ ; 9: e12005, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34466291

RESUMO

Remote-sensing using normalized difference vegetation index (NDVI) has the potential of rapidly detecting the effect of water stress on field crops. However, this detection has typically been accomplished only after the stress effect led to significant changes in crop green biomass, leaf area index, angle and position, and few studies have attempted to estimate the uncertainties of the regression models. These have limited the informed interpretation of NDVI data in agricultural applications. We built a ground-based sensing cart and used it to calibrate the relationships between NDVI and leaf water potential (LWP) for wheat, corn, and cotton growing under field conditions. Both the methods of ordinary least-squares (OLS) and weighted least-squares (WLS) were employed in data analysis, and measurement errors in both LWP and NDVI were considered. We also used statistical resampling to test the effect of measurement errors of LWP on the uncertainties of model coefficients. Our data showed that obtaining a high value of the coefficient of determination did not guarantee a high prediction precision in the obtained regression models. Large prediction uncertainties were estimated for all three crops, and the regressions obtained were not always significant. The best models were obtained for cotton with a prediction uncertainty of 27%. We found that considering measurement errors for both LWP and NDVI led to reduced uncertainties in model coefficients. Also, reducing the sample size of LWP measurement led to significantly increased uncertainties in the coefficients of the linear models describing the LWP-NDVI relationship. Finally, potential strategies for reducing the uncertainty relative to the range of NDVI measurement are discussed.

19.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(9): 889-895, 2021.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-34535202

RESUMO

OBJECTIVES: To investigate the incidence of maternal group B Streptococcus (GBS) colonization and neonatal early-onset GBS disease (GBS-EOD), and to study the factors associated with the development of GBS-EOD in the offspring of pregnant women with GBS colonization. METHODS: A total of 16 384 pregnant women and 16 634 neonates delivered by them were enrolled prospectively who had medical records in Xiamen Maternal and Child Care Hospital, Beijing Obstetrics and Gynecology Hospital of Capital Medical University, and Zhangzhou Zhengxing Hospital from May 1, 2019 to April 30, 2020. Unified GBS screening time, culture method, and indication for intrapartum antibiotic prophylaxis (IAP) were adopted in the three hospitals. The incidence rates of maternal GBS colonization and neonatal GBS-EOD were investigated. A multivariate logistic regression analysis was used to identify the factors associated with the development of GBS-EOD in the offspring of pregnant women with GBS colonization. RESULTS: In these three hospitals, the positive rate of GBS culture among the pregnant women in late pregnancy was 11.29% (1 850/16 384), and the incidence rate of neonatal GBS-EOD was 0.96‰ (16/16 634). The admission rate of live infants born to the GBS-positive pregnant women was higher than that of those born to the GBS-negative ones (P<0.05). The live infants born to the GBS-positive pregnant women had a higher incidence rate of GBS-EOD than those born to the GBS-negative ones [6.38‰ (12/1 881) vs 0.27‰ (4/14 725), P<0.05]. The multivariate logistic regression analysis showed that placental swabs positive for GBS and positive GBS in neonatal gastric juice at birth were independent predictive factors for the development of GBS-EOD (P<0.05), while adequate IAP was a protective factor (P<0.05) in the offspring of pregnant women with GBS colonization. CONCLUSIONS: GBS colonization of pregnant women in late pregnancy has adverse effects on their offspring. It is important to determine prenatal GBS colonization status of pregnant women and administer with adequate IAP based on the indications of IAP to reduce the incidence of neonatal GBS-EOD. Citation.


Assuntos
Complicações Infecciosas na Gravidez , Infecções Estreptocócicas , Antibioticoprofilaxia , Feminino , Humanos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Placenta , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/epidemiologia , Estudos Prospectivos , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/epidemiologia , Streptococcus agalactiae
20.
Genes Dis ; 8(6): 931-938, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34522719

RESUMO

Methyltetrahydrofolate reductase (MTHFR) is a key enzyme in folate metabolism, and its single nucleotide polymorphism (SNP) site C677T may be associated with gastrointestinal cancer. However, the relationship between MTHFR C677T polymorphism and gastrointestinal tumor markers carcinoma embryonic antigen (CEA), carbohydrate antigen 199 (CA199) and carbohydrate antigen 724 (CA724) in Helicobacter pylori (H. pylori) infection is not specified. This study aims to identify the association between MTHFR C677T polymorphism and gastrointestinal tumor markers (CEA, CA199 and CA724) in H. pylori infection. The relationship between MTHFR C677T polymorphism and gastrointestinal tumor markers in 58 patients with H. pylori infection and 94 non-infected patients was studied. We found that TT genotype was a susceptibility factor of H. pylori infection, which was also associated with increased CEA and CA724 levels. Moreover, there was a negative additive interaction between MTHFR gene C677T polymorphism and CEA levels in H.pylori infection. Meanwhile, there were significant differences in CEA levels between MTHFR C677T polymorphism and H.pylori infection. The presence of T allele led to a decrease in CEA levels when 13C urea breath test (13C-UBT) was positive, while the presence of T allele led to an increase in CEA levels when 13C-UBT was negative. Therefore, we suggest that healthy people should take MTHFR C677T polymorphism screening, combined with 13C-UBT and gastrointestinal tumor markers detection, which can screen out the susceptible population of H. pylori, and help to detect gastrointestinal cancer in the early stage.

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