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1.
Plant Dis ; 2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38616399

RESUMO

Oaks are the most abundant trees in naturally regenerated forests in China, play a crucial role in preventing soil erosion and maintaining ecological stability (Du et al. 2022). Quercus guyavifolia H. Léveillé (Fagaceae family, Subgenus Cerris, section Ilex), is endemic in China, distributed in the southeastern boundary of the Qinghai-Tibet Plateau, with elevations from 2, 000 - 4, 500 m a.s.l. (Denk et al. 2018; Sun et al. 2016). Powdery mildew is a prevalent disease of oaks with up to 60% of foliage infection, which can induce leaf necrosis or deformation and might contribute to oak decline (Marçais and Desprez-Loustau 2014). In September 2023, we found leaves of Q. guyavifolia near Yunnan Baima Snow Mountain covered with white fungal colonies. Diseased Q. guyavifolia plants were transplanted into a greenhouse at Yunnan University for pathogenicity tests. Conidia from diseased plants were blown into twenty healthy Q. guyavifolia seedlings by cold air blower and five non-inoculated healthy seedlings were used as control. The inoculated seedlings developed powdery mildew symptoms within ten days on both sides of the leaves. Trypan blue staining was used to identify the pathogen that infects Q. guyavifolia (Xiao et al. 2017). Microscopic examination revealed abundant conidia and extensive branched hyphae on leaves, similar to the characteristics of powdery mildew fungi. The mean length and width of conidia were 29.06 ± 3.96 × 9.52 ± 1.36 µm (n = 50). We collected fungi (YNBAIMAXS01) and extracted genomic DNA from five diseased plants (from the same location) using the CTAB method. We amplified and sequenced the ITS (Gardes and Bruns, 1993), MS294, and MS447 (two nuclear protein-encoding genes; Feau et al. 2011; GenBank numbers: PP079015, PP083693, PP083694). BLAST analysis revealed 100% identity of above three sequences with the ITS of Erysiphe quercicola isolate DACA010 (GenBank accession MT569439), MS294 of E. quercicola isolate GEM09_11_FRTB1 (GenBank accession KY348509), and MS447 of E. quercicola isolate A1I1.5 (GenBank accession KY466619). Therefore, the isolate YNBAIMAXS01 was identified as E. quercicola based on its morphological and molecular characteristics. Sequences from the above three regions for YNBAIMAXS01 and five Erysiphe species were used to construct a Maximum likelihood (ML) tree. In addition, we constructed a ML tree using only the ITS region of YNBAIMAXS01 and eight Erysiphe species from GenBank to better distinguish E. quercicola from these species. Both trees were constructed using MEGA X with K2 + G as best model. The ML trees confirmed the powdery mildew fungi isolated from Q. guyavifolia is closely related to E. alphitoides. To date, thirty-four powdery mildew species belonging to genus Erysiphe have been found affecting Quercus and nine oak species can be infected by E. quercicola (https://fungi.ars.usda.gov/). To our knowledge, this is the first report of powdery mildew caused by E. quercicola on Q. guyavifolia, thus the development of control strategies and disease management is urgently needed.

2.
Biosaf Health ; 5(2): 89-100, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37123450

RESUMO

With continuous mutations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the severe immune escape of Omicron sub-variants urges the development of next-generation broad-spectrum vaccines, especially as booster jabs after high-level vaccination coverage of inactivated vaccines in China and many other countries. Previously, we developed a coronavirus disease 2019 (COVID-19) protein subunit vaccine ZF2001® based on the tandem homo-prototype receptor-binding domain (RBD)-dimer of the SARS-CoV-2 spike protein. We upgraded the antigen into a hetero-chimeric prototype (PT)-Beta or Delta-BA.1 RBD-dimer to broaden the cross-protection efficacy and prove its efficiency with protein subunit and mRNA vaccine platforms. Herein, we further explored the hetero-chimeric RBD-dimer mRNA vaccines and evaluated their broad-spectrum activities as booster jabs following two doses of inactivated vaccine (IV) in mice. Our data demonstrated that the chimeric vaccines significantly boosted neutralizing antibody levels and specific T-cell responses against the variants, and PT-Beta was superior to Delta-BA.1 RBD as a booster in mice, shedding light on the antigen design for the next-generation COVID-19 vaccines.

3.
J Sci Food Agric ; 103(7): 3659-3673, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36754602

RESUMO

BACKGROUND: Chestnut (Castanea mollissima) shell is rich in flavonoids and our previous studies showed that proanthocyanins and anthocyanins were the two markedly varied flavonoids in chestnut shell extracts (CSE) during digestion. Here, the biotransformation of proanthocyanins and anthocyanins in a simulated gastrointestinal model, and the interactions between non-absorption CSE (NACSE) and gut microbiota in vitro, were investigated by ultra-high-performance liquid chromatography combined with triple-quadrupole mass spectrometry and 16S rRNA sequencing. RESULTS: Chestnut shell was richer in proanthocyanins and anthocyanins, while the loss of proanthocyanins was greater after digestion. Additionally, the content of anthocyanin decreased after gastric digestion but increased after intestinal digestion and remained stable after fermentation. After fermentation, delphinidin-3-O-sambubioside and pelargonidin-3-O-galactoside were newly formed. Furthermore, microbiome profiling indicated that NACSE promoted the proliferation of beneficial bacteria, while inhibiting pathogenic bacteria. CONCLUSION: All these data suggest that CSE may be a promising candidate to protect gut health. © 2023 Society of Chemical Industry.


Assuntos
Antocianinas , Microbioma Gastrointestinal , Antocianinas/química , Biotransformação , Digestão , Flavonoides , RNA Ribossômico 16S , Fagaceae/química , Extratos Vegetais/farmacologia
4.
Front Psychiatry ; 13: 966758, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36213916

RESUMO

Objectives: Diabetes and its complications are commonly associated with depressive symptoms, and few studies have investigated the diagnosis effect of depressive symptoms in patients with diabetes. The present study used a network-based approach to explore the association between depressive symptoms, which are annotated from electronic health record (EHR) notes by a deep learning model, and the diagnosis of type 2 diabetes mellitus (T2DM) and its complications. Methods: In this study, we used anonymous admission notes of 52,139 inpatients diagnosed with T2DM at the first affiliated hospital of Nanjing Medical University from 2008 to 2016 as input for a symptom annotation model named T5-depression based on transformer architecture which helps to annotate depressive symptoms from present illness. We measured the performance of the model by using the F1 score and the area under the receiver operating characteristic curve (AUROC). We constructed networks of depressive symptoms to examine the connectivity of these networks in patients diagnosed with T2DM, including those with certain complications. Results: The T5-depression model achieved the best performance with an F1-score of 91.71 and an AUROC of 96.25 compared with the benchmark models. The connectivity of depressive symptoms in patients diagnosed with T2DM (p = 0.025) and hypertension (p = 0.013) showed a statistically significant increase 2 years after the diagnosis, which is consistent with the number of patients diagnosed with depression. Conclusion: The T5-depression model proposed in this study can effectively annotate depressive symptoms in EHR notes. The connectivity of annotated depressive symptoms is associated with the diagnosis of T2DM and hypertension. The changes in the network of depressive symptoms generated by the T5-depression model could be used as an indicator for screening depression.

5.
New Phytol ; 236(2): 714-728, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35811425

RESUMO

Hemiepiphytic figs killing their host trees is an ecological process unique to the tropics. Yet the benefits and adaptive strategies of their special life history remain poorly understood. We compared leaf phosphorus (P) content data of figs and palms worldwide, and functional traits and substrate P content of hemiepiphytic figs (Ficus tinctoria), their host palm and nonhemiepiphytic conspecifics at different growth stages in a common garden. We found that leaf P content of hemiepiphytic figs and their host palms significantly decreased when they were competing for soil resources, but that of hemiepiphytic figs recovered after host death. P availability in the canopy humus and soil decreased significantly with the growth of hemiepiphytic figs. Functional trait trade-offs of hemiepiphytic figs enabled them to adapt to the P shortage while competing with their hosts. From the common garden to a global scale, the P competition caused by high P demand of figs may be a general phenomenon. Our results suggest that P competition is an important factor causing host death, except for mechanically damaging and shading hosts. Killing hosts benefits hemiepiphytic figs by reducing interspecific P competition and better acquiring P resources in the P-deficient tropics, thereby linking the life history strategy of hemiepiphytic figs to the widespread P shortage in tropical soils.


Assuntos
Ficus , Vespas , Animais , Fósforo , Folhas de Planta , Solo , Árvores
7.
Front Plant Sci ; 10: 1286, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31681381

RESUMO

The AP2 transcription factors play important roles in regulating plant growth and development. However, limited data are available on the contributions of AP2 transcription factors in wheat (Triticum aestivum L.). In the present study, a total of 62 AP2 genes were identified in wheat from a genome-wide search against the latest wheat genome data. Phylogenetic and sequence alignment analyses divided the wheat AP2 genes into 3 clusters, euAP2, euANT, and basalANT. Chromosomal distribution, gene structure and duplication, and motif composition were subsequently investigated. The 62 TaAP2 genes were unevenly distributed on 21 chromosomes. Twenty-four homologous gene sets among A, B, and D sub-genomes were detected, which contributed to the expansion of the wheat AP2 gene family. The expression levels of TaAP2 genes were examined using the WheatExp database; most detected genes exhibited tissue-specific expression patterns. The transcript levels of 9 randomly selected TaAP2 genes were validated through qPCR analyses. Overexpression of TaAP2-10-5D, the most likely homolog of Arabidopsis ANT gene, increased organ sizes in Arabidopsis. Our results extend our knowledge of the AP2 gene family in wheat, and contribute to further functional characterization of AP2s during wheat development with the ultimate goal of improving crop production.

8.
BMC Cancer ; 17(1): 222, 2017 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-28347288

RESUMO

BACKGROUND: ATP-binding cassette sub-family G member 2 (ABCG2) is a semi-transport protein that plays a major role in multidrug resistance. We aimed to evaluate the prognostic significance of ABCG2 expression in patients with clear cell renal cell carcinoma. METHODS: From 2008 to 2013, 120 patients with clear cell kidney cancer underwent surgery with paraffin-embedded specimens and necessary clinical information available. Immunohistochemistry staining was performed to grade the expression of ABCG2 as ABCG2(-): less than 10% of tumor cells stained; ABCG2(+): weak membrane staining; and ABCG2(++): moderate or strong membrane staining. The overall survival was analyzed using Kaplan-Meier method. Multivariable Cox regression evaluated the independent predictors for overall survival. RESULTS: ABCG2(-) was diagnosed in 57 (48%) patients, ABCG2(+) in 52 (43%) patients, and ABCG2 (++) in 11(9.2%) patients. ABCG2 expression significantly correlated with the five-year survival (p < 0.001) and distant metastasis (p = 0.001). In the multivariable analysis, besides Fuhrman grade, the ABCG2 expression was an independent prognostic marker for overall survival (p < 0.001) when incorporating other relevant tumor and clinical parameters (HR = 3.84, 95% CI: 1.92-7.70). CONCLUSION: The current data suggests that ABCG2 may serve as a prognostic marker for overall survival in patients with clear cell renal cell carcinoma. Further studies with large cohorts of patients will be essential for validating these findings and defining the clinical utility of ABCG2 in the patient population.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Carcinoma de Células Renais/genética , Intervalo Livre de Doença , Proteínas de Neoplasias/genética , Prognóstico , Idoso , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/cirurgia , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias
9.
AoB Plants ; 82016.
Artigo em Inglês | MEDLINE | ID: mdl-27339052

RESUMO

Epiphytes are an important component of tropical and subtropical flora, and serve vital ecological functions in forest hydrology and nutrient fluxes. However, they often encounter water deficits because there is no direct contact between their roots and the soil. The strategies employed by epiphytes for maintaining water balance in relatively water-limited habitats are not completely understood. In the present study, we investigated the anatomical traits, water loss rates, and physiology of leaves and pseudobulbs of four Dendrobium species with different pseudobulb morphologies to understand the roles of leaf and pseudobulb in maintaining water balance of epiphytic orchids. Our results showed that two species (D. chrysotoxum and D. officinale), with lower rates of water loss, have thicker leaves and upper cuticles, but lower epidermal thickness and leaf dry mass per area. In contrast, the other two species (D. chrysanthum and D. crystallinum) with thinner cuticles and higher rates of water loss, have less tissue density and greater saturated water contents in their pseudobulbs. Therefore, our results indicate that these latter two species may resist drought by storing water in the pseudobulbs to compensate for their thin cuticles and rapid water loss through the leaves. Under the same laboratory conditions, excised pseudobulbs with attached leaves had lower rates of water loss when compared with samples comprising only excised leaves. This implies that epiphytic orchids utilize two different strategies for sustaining water balance: thick cuticles to conserve water in leaves and water storage in pseudobulbs. Our results also show that Dendrobium species with thin cuticles tend to have pseudobulbs with high water storage capacity that compensates for their faster rates of water loss. These outcomes contribute to our understanding of the adaptive water-use strategies in Dendrobium species, which is beneficial for the conservation and cultivation of epiphytic orchids.

10.
PLoS One ; 10(10): e0140384, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26461108

RESUMO

Most palm species occur in the shaded lower strata of tropical rain forests, but how their traits relate to shade adaptation is poorly understood. We hypothesized that palms are adapted to the shade of their native habitats by convergent evolution towards high net carbon gain efficiency (CGEn), which is given by the maximum photosynthetic rate to dark respiration rate ratio. Leaf mass per area, maximum photosynthetic rate, dark respiration and N and P concentrations were measured in 80 palm species grown in a common garden, and combined with data of 30 palm species growing in their native habitats. Compared to other species from the global leaf economics data, dicotyledonous broad-leaved trees in tropical rainforest or other monocots in the global leaf economics data, palms possessed consistently higher CGEn, achieved by lowered dark respiration and fairly high foliar P concentration. Combined phylogenetic analyses of evolutionary signal and trait evolution revealed convergent evolution towards high CGEn in palms. We conclude that high CGEn is an evolutionary strategy that enables palms to better adapt to shady environments than coexisting dicot tree species, and may convey advantages in competing with them in the tropical forest understory. These findings provide important insights for understanding the evolution and ecology of palms, and for understanding plant shade adaptations of lower rainforest strata. Moreover, given the dominant role of palms in tropical forests, these findings are important for modelling carbon and nutrient cycling in tropical forest ecosystems.


Assuntos
Adaptação Fisiológica , Arecaceae/fisiologia , Evolução Biológica , Carbono/metabolismo , Respiração Celular , Fotossíntese , Filogenia , Folhas de Planta/fisiologia , Característica Quantitativa Herdável , Especificidade da Espécie
11.
Tree Physiol ; 35(9): 964-74, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26232783

RESUMO

To understand water-use strategies of woody bamboo species, sap flux density (Fd) in the culms of a woody bamboo (Bambusa vulgaris Schrader ex Wendland) was monitored using the thermal dissipation method. The daytime and night-time Fd were analyzed in the dry and rainy seasons. Additionally, diurnal changes in root pressure, culm circumference, and stomatal conductance (gs) were investigated to characterize the mechanisms used to maintain diurnal water balance of woody bamboos. Both in the dry and rainy seasons, daytime Fd responded to vapor pressure deficit (VPD) in an exponential fashion, with a fast initial increase in Fd when VPD increased from 0 to 1 kPa. The Fd and gs started to increase very fast as light intensity and VPD increased in the morning, but they decreased sharply once the maximum value was achieved. The Fd response of this woody bamboo to VPD was much faster than that of representative trees and palms growing in the same study site, suggesting its fast sap flow and stomatal responses to changes in ambient environmental factors. The Fd in the lower and higher culm positions started to increase at the same time in the morning, but the Fd in the higher culm position was higher than that of the lower culm in the afternoon. Consistently, distinct decreases in its culm circumference in the afternoon were detected. Therefore, unlike trees, water storage of bamboo culms was not used for its transpiration in the morning but in the afternoon. Nocturnal sap flow of this woody bamboo was also detected and related to root pressure. We conclude that this bamboo has fast sap flow/stomatal responses to irradiance and evaporative demands, and it uses substantial water storage for transpiration in the afternoon, while root pressure appears to be a mechanism resulting in culm water storage recharge during the night.


Assuntos
Bambusa/fisiologia , Escuridão , Caules de Planta/fisiologia , Água , Madeira/fisiologia , Ritmo Circadiano , Fótons , Fotossíntese , Exsudatos de Plantas , Raízes de Plantas/fisiologia , Chuva , Estações do Ano , Temperatura , Pressão de Vapor
12.
Can Urol Assoc J ; 8(11-12): E821-7, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25485010

RESUMO

INTRODUCTON: We wanted to identify the prognostic factors for overall survival (OS) in Chinese patients with metastatic renal cell carcinoma (mRCC) treated with first-line targeted therapy (sorafenib or sunitinib). METHODS: We retrospectively reviewed clinical data from 119 mRCC patients administered sorafenib or sunitinib at the Ruijin Hospital since 2007. OS rates were calculated by the Kaplan-Meier method. Each variable was investigated univariately and then multivariately using a stepwise algorithm. A multivariate Cox regression model analyzed baseline variables for prognostic significance. RESULTS: The mean patient age was 57 ± 12 years; 37 patients (31%) received sorafenib and 82 (69%) received sunitinib. The mean OS was 22.7 ± 15.6 months (range: 2.8- 68.7). OS rates at year 1, 3 and 5 were 74%, 57%, and 36%, respectively. Univariate analysis identified significant negative prognostic factors (p < 0.05) as Eastern Cooperative Oncology Group (ECOG) performance status ≥2, symptoms, no prior nephrectomy, microscopic necrosis, ≥2 metastatic sites, presence of liver, bone, or pancreas metastasis, hemoglobin less than the lower limit of normal(female <115 g/L, male <130 g/L), and serum alkaline phosphatase greater than the upper limit of normal (126 IU/L) at baseline, as well as a relative dose intensity of targeting agents in the first month (1M-RDI) of <50%. Multivariate analysis of OS identified 4 independent predictors: no symptoms, no bone or pancreas metastasis, and 1M-RDI of targeting agents (≥50%). CONCLUSIONS: With targeted therapy, there is some change in the prognostic factors for mRCC and target drug therapies (1M-RDI ≥50%) play an important role in the prognosis of mRCC. Continued progress in the identification of patient-specific prognostic factors for mRCC will require further advances in the understanding of tumour biology.

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