Ultrasound Pretreatment for Enhancing Fine and Ultrafine Flake Graphite Flotation Beneficiation.

With the severe depletion of coarse flake graphite (a critical raw material) resources, developing and utilizing fine and ultrafine graphite resources have recently attracted attention. Froth flotation is a widely used technique for the initial enrichment of graphite; however, the flotation selectivity decreases significantly along with particle size reduction. Ultrasound pretreatment would be a promising method to improve the flotation of fine particles. As an innovative approach to understand better the flotation response of different flake graphite sizes, this study conducted a comparative analysis based on flotation concentrate yield and ash as well as ash removal rate between the flake graphite with various particle sizes after ultrasound pretreatment. Particle size, X-ray powder diffraction, and scanning electron microscopy and energy dispersive X-ray spectroscopy analyses were used to investigate the effect of ultrasound treatment on mineralogical properties of the flake graphite with varied particle sizes. Process outcomes indicated that the flotation performance of fine flake graphite (mean chord length: 62.63 µm) was significantly enhanced after ultrasound pretreatment. However, flotation of the ultrafine flake graphite (mean chord length: 24.97 µm) after ultrasound treatment was limited due to the difficulty of generating sufficient fragmentation and dissociation by microjets and shock waves formed by the cavitation effect. Compared with conventional flotation, the concentrate yield of ultrasound flotation increased from 88.95 to 94.98%, ash content decreased from 5.72 to 4.87%, and ash removal rate enhanced from 36.94 to 42.61%. Particle size and mineral property analyses confirmed that further crushing and dissociation of the larger flake graphite after ultrasound pretreatment would be the main factors contributing to improved flotation performance. Additionally, the formation of air flocs in the coarse flake graphite during the ultrasound pretreatment process facilitated the flotation recovery of the crushed graphite particles.

A comparative study on the influence of single and combined ultrasounds assisted flake graphite flotation.

Ultrasound has emerged as a promising technique for improving the mineral flotation performance. However, limited research exists regarding the influence of different ultrasound types on the flotation process. Specifically, the impact of combined ultrasound and the comparison of horn- and bath-type ultrasounds on flotation have not been fully investigated. To address this knowledge gap, a comprehensive study to explore the effects of different ultrasonic pretreatments on the flotation of flake graphite was conducted. A Box-Behnken design is employed to analyze the effects of combined ultrasound on graphite flotation. By characterizing the properties of graphite samples before and after the ultrasonic treatment, the aim is to elucidate the mechanism underlying the impact of ultrasound on graphite flotation. The experimental results indicated that the ultrasonic cavitation intensity exerted a significant influence on the graphite flotation recovery. Both horn- and bath- type ultrasounds contributed to flotation, but horn-type ultrasound demonstrated a more pronounced effect, leading to a 7% increase in flotation recovery, whereas bath-type ultrasound resulted in only a 2% increase. Furthermore, the cavitation intensity of combined ultrasound was found to be higher than that of single-frequency ultrasound in the same duration. However, the performance of graphite flotation was better with short duration combined ultrasound pretreatment, while the opposite trend was observed for a long duration ultrasound pretreatment. These findings may inform the development of more efficient and effective ultrasonic pretreatments for flotation separation processes.

Zhx2 maintains islet ß-cell mass and function by transcriptionally regulating Pax6.

Emerging evidence shows that pancreatic ß-cell function and quality are key determinants in the progression of type 2 diabetes (T2D). The transcription factor zinc finger homeobox 2 (Zhx2) is involved in proliferation and development of multiple cells. However, the exact role of Zhx2 in ß-cells and T2D remains completely unknown. Here, we report that Zhx2 orchestrates ß-cell mass and function by regulating paired box protein pax-6 (Pax6). We found that ß-cell-specific knockout Zhx2 (Zhx2BKO) mice showed a decrease in ß-cell proliferation and glucose homeostasis. Under prediabetic and diabetic conditions, we discovered glucose intolerance in both Zhx2BKO-HFD mice and Zhx2BKO-db/db mice, with reduced ß-cell mass and insulin secretion. Mechanistically, we demonstrated that Zhx2 targeted the Pax6 promoter region (-1740∼-1563; -862∼-559; -251∼+75), enhanced promoter activity. Overall, Zhx2 maintains ß-cell function by transcriptionally regulating Pax6, which provides a therapeutic target for diabetes intervention.

Characterization of Banana SNARE Genes and Their Expression Analysis under Temperature Stress and Mutualistic and Pathogenic Fungal Colonization.

SNAREs (soluble N-ethylmaleimide-sensitive-factor attachment protein receptors) are engines for almost all of the membrane fusion and exocytosis events in organism cells. In this study, we identified 84 SNARE genes from banana (Musa acuminata). Gene expression analysis revealed that the expression of MaSNAREs varied a lot in different banana organs. By analyzing their expression patterns under low temperature (4 °C), high temperature (45 °C), mutualistic fungus (Serendipita indica, Si) and fungal pathogen (Fusarium oxysporum f. sp. Cubense Tropical Race 4, FocTR4) treatments, many MaSNAREs were found to be stress responsive. For example, MaBET1d was up-regulate by both low and high temperature stresses; MaNPSN11a was up-regulated by low temperature but down-regulated by high temperature; and FocTR4 treatment up-regulated the expression of MaSYP121 but down-regulated MaVAMP72a and MaSNAP33a. Notably, the upregulation or downregulation effects of FocTR4 on the expression of some MaSNAREs could be alleviated by priorly colonized Si, suggesting that they play roles in the Si-enhanced banana wilt resistance. Foc resistance assays were performed in tobacco leaves transiently overexpressing MaSYP121, MaVAMP72a and MaSNAP33a. Results showed that transient overexpression of MaSYP121 and MaSNPA33a suppressed the penetration and spread of both Foc1 (Foc Race 1) and FocTR4 in tobacco leaves, suggesting that they play positive roles in resisting Foc infection. However, the transient overexpression of MaVAMP72a facilitated Foc infection. Our study can provide a basis for understanding the roles of MaSNAREs in the banana responses to temperature stress and mutualistic and pathogenic fungal colonization.

Effect of ultrasound power on HCl leaching kinetics of impurity removal of aphanitic graphite.

This study aimed to investigate the effect of ultrasonic power and temperature on the impurity removal rate during conventional and ultrasonic-assisted leaching of aphanitic graphite. The results showed that the ash removal rate increased gradually (∼50 %) with the increase in ultrasonic power and temperature but deteriorated at high power and temperature. The unreacted shrinkage core model was found to fit the experimental results better than other models. The Arrhenius equation was used to calculate the finger front factor and activation energy under different ultrasonic power conditions. The ultrasonic leaching process was significantly influenced by temperature, and the enhancement of the leaching reaction rate constant by ultrasound was mainly reflected in the increase of the pre-exponential factor A. Ultrasound treatment improved the efficiency of impurity mineral removal by destroying the inert layer formed on the graphite surface, promoting particle fragmentation, and generating oxidation radicals. The poor reactivity of hydrochloric acid with quartz and some silicate minerals is a bottleneck limiting the further improvement of impurity removal efficiency in ultrasound-assisted aphanitic graphite. Finally, the study suggests that introducing fluoride salts may be a promising method for deep impurity removal in the ultrasound-assisted hydrochloric acid leaching process of aphanitic graphite.

Investigating spatial variations in dynamic cerebral autoregulation through a computational model of stenosis.

Objective. Dynamic cerebral autoregulation (dCA) is a well-established mechanism that acts to maintain cerebral blood flow (CBF) reasonably constant in response to short-term fluctuations in blood pressure. It is known to be impaired in many clinical conditions, including stenosis, which is also a major risk factor for ischaemic stroke. However, it is not yet well understood whether impairment in dCA in one brain region is independent or not on dCA impairment in other brain regions, for example, whether there are spatial effects of stenosis on dCA. This is due to the complex blood flow environment and the lack of physiological experiments.Approach. We thus establish and apply a novel computational stenosis model including the circle of Willis to investigate and to quantify the degree of dCA impairment and CBF patterns as a function of stenosis fraction, measured in different configurations of the cerebral vasculature.Main results. We find some evidence for dependence between dCA in different brain regions, although this is very preliminary and much more experimental data will be required to answer this question fully.Significance.Our study has provided a first attempt to consider the effect of stenosis in various arteries on cerebral autoregulation to investigate spatial variations in dCA. This has potential applications in the treatment of cerebrovascular diseases where the control of cerebral perfusion is critical but where measurements are scarce.

TIM-4 orchestrates mitochondrial homeostasis to promote lung cancer progression via ANXA2/PI3K/AKT/OPA1 axis.

Mitochondrial function and homeostasis are critical to the proliferation of lung cancer cells. T-cell immunoglobulin and mucin domain-containing molecule 4 (TIM-4) promotes the development and progression of lung cancer. However, the role of TIM-4 in mitochondria homeostasis in tumor cells remains completely unknown. In this study, we found that TIM-4 promoted growth and proliferation of lung cancer cells by the oxidative phosphorylation (OXPHOS) pathway. Consistently, inhibition of OXPHOS reversed TIM-4-induced proliferation of lung cancer cells. Notably, TIM-4 promoted mitochondrial fusion via enhancing L-OPA1 protein expression. Mechanistically, TIM-4 regulated protein of L-OPA1 through the PI3K/AKT pathway, and TIM-4 interacted with ANXA2 to promote the activation of PI3K/AKT signaling. Collectively, TIM-4 promotes oxidative phosphorylation of lung cancer cells to accelerate tumor progress via ANXA2/PI3K/AKT/OPA1 axis, which sheds significant new lights on the potential role of TIM-4 in regulating tumor cell metabolism.

A method for high-concentration agarose gel preparation and its application in high-resolution separation of low-molecular-weight nucleic acids and proteins.

Separation of nucleic acids and proteins using gels has always been a crucial part of molecular biology research. For low-molecular-weight nucleic acids and proteins, low- and medium-concentration agarose gels cannot achieve the high resolution as polyacrylamide gels. We found that 6 %-14 % high-concentration agarose gels (HAGs) could be easily dissolved in an autoclave and the vertical gel cast can be effortlessly filled using an easy-made plastic box. Coupled with the improved buffer condition, HAG electrophoresis resulted in a good resolution of DNA and protein bands. With conventional TBE buffer plus 0.2 % NaCl, DNA fragments that differ by 2-5-bp within the 50-200-bp size range can be resolved on 6 %-8 % HAGs. By using TBE without NaCl, DNA fragments that differ by 2-bp or 2-nt within the 10-100-bp size range can be well resolved on >8 % HAGs. Using a buffer system comprising 1 M Tris-Cl for gel preparation, 0.2 M Tris-Cl/0.2 % SDS as upper tank buffer, and 0.2 M Tris-Cl as the lower tank buffer, HAGs achieved good molecular weight separation of total bacterial and plant proteins in the 10-200 kDa range. In conclusion, we developed a method for HAG preparation and electrophoresis of low-molecular-weight nucleic acids and proteins.

T-cell immunoglobulin- and mucin-domain-containing molecule-4 maintains adipose tissue homeostasis by orchestrating M2 macrophage polarization via nuclear factor kappa B pathway.

Obesity is generally associated with low-grade inflammation. Adipose tissue macrophages (ATMs) orchestrate metabolic inflammation. The classical (M1-like) or alternative (M2-like) activation of ATMs is functionally coupled with the metabolic status of fat tissues. It has been found that T-cell immunoglobulin- and mucin-domain-containing molecule-4 (Tim-4) inhibits inflammation by regulating macrophages. However, the exact role of Tim-4 in macrophage polarization and obesity remains unknown. Here, we identified Tim-4 as a critical switch governing macrophage M1/M2 polarization and energy homeostasis. Tim-4 deletion led to spontaneous obesity in elder mice and promoted obesity severity of db/db mice. Obesity microenvironment enhanced the expression of Tim-4 in white adipose tissue and ATMs. In vitro, we detected an increase in M1-like cells and decrease in M2-like cells in both peritoneal macrophages and bone marrow-derived macrophages from Tim-4 knockout mice. Mechanistically, we demonstrated that Tim-4 promoted M2-like macrophages polarization via suppressing nuclear factor kappa B (NF-κB) signaling pathway. In addition, we found that Tim-4 promoted TLR4 internalization, which might contribute to regulation of NF-κB signaling. Collectively, these results indicated that Tim-4 maintained adipose tissue homeostasis by regulating macrophage polarization via NF-κB pathway, which would provide a new target for obesity intervention.

Risk factors and prognosis of acute cerebrovascular events at 1 year after hip fracture in elderly patients / 中国骨伤

OBJECTIVE@#To investigate risk factors of acute cerebrovascular events and effects on the prognosis within 1 year after hip fracture surgery.@*METHODS@#A retrospective analysis was performed on 320 elderly patients with hip fracture treated from July 2017 to December 2020, including 111 males and 209 females, aged from 60 to 101 years old with an average of (79.05±8.48) years old. According to whether acute cerebrovascular events occurred within 1 year after surgery, patients were divided into cerebrovascular events and non-cerebrovascular events group. Clinical data of patients were collected, including age, sex, comorbidities, fracture type, white blood cell count, hemoglobin, albumin, activities of daily living (ADL) score, walking ability, type of anesthesia, type of surgery, and length of hospital stay, Univariate analysis and multivariate Logistic regression were used to analyze the independent risk factors of acute cerebrovascular events within 1 year after hip fracture in elderly patients. ADL, walking ability and mortality were compared between the two groups 1 year after surgery.@*RESULTS@#Acute cerebrovascular events occurred in 38 patients (11.9%) within 1 year after surgery. In the cerebrovascular events group, there were 20 males and 18 females, aged (82.53±7.91) years. In the non-cerebrovascular event group, there were 91 males and 191 females, aged with an average of (78.59±8.46) years old . Univariate analysis showed that acute cerebrovascular events were associated with age (t=2.712, P=0.007), male (χ2=6.129, P=0.013), hypertension (χ2=8.449, P=0.004), arrhythmia (χ2=6.360, P=0.012), stroke history (χ2=34.887, P=0.000), diabetes mellitus (χ2=4.574, P=0.032) and length of hospital stay (t=2.249, P=0.025) were closely related. Multivariate Logistic regression analysis showed age (OR=1.068, P=0.018), male (OR=2.875, P=0.008), arrhythmia (OR=2.722, P=0.017) and stroke history (OR=7.382, P=0.000) was an independent risk factor for acute cerebrovascular events 1 year after surgery. The patients with cerebrovascular events died at 1 year after surgery (11 cases) compared with those without cerebrovascular events (41 cases), and the difference was statistically significant(χ2=5.108, P=0.024). ADL scores of patients with cerebrovascular events at 1 year after operation were (58.70±14.45) points compared with those without cerebrovascular events (67.83±10.45) points, and the difference was statistically significant(t=4.122, P=0.000). Independent walking, assisted walking and bed rest were 3, 17 and 7 cases in cerebrovascular event group, and 54, 174 and 13 cases in non-cerebrovascular event group, respectively;and the difference was statistically significant(χ2=11.030, P=0.003).@*CONCLUSION@#Acute cerebrovascular events were common in elderly patients 1 year after hip fracture. Age, male, arrhythmia and stroke history were independent risk factors for acute stroke. The patients in the cerebrovascular event group had higher mortality and worse self-care ability and walking ability one year after operation.

GPER inhibitor increases tamoxifen-induced apoptosis in T-47DTR-resistant cells / 中国药理学通报

Aim To study the effect of G protein-coupled estrogen receptor(GPER)inhibitor G15 on the sensitivity of breast cancer tamoxifen-resistant cells to T-47DTR. Methods Experiments were carried out with 4-hydroxytamoxifen(4-OHT),the active form of tamoxifen in vivo. The sensitivity of tamoxifen-resistant breast cancer cell line T-47DTR and its parental cell line T-47D to tamoxifen was detected by MTT assay; the expression of GPER protein was analyzed by plasma separation of inhibitor G15; the effect of 4-OHT combined with G15 on the apoptosis of T-47DTR cells was analyzed by flow cytometry AnnexinV-FITC/PI double staining; the expression levels of apoptosis-related proteins Bax,Bcl-2,caspase-3,cleaved caspase-3,caspase-9,cleaved caspase-9 were analysed by Western blot. Results(1)Compared with the parental cell T-47D,the resistance of T-47DTR-resistant cells to 4-OHT was significantly enhanced.(2)When 4-OHT(2 μmol·L-1)was administered,the membrane distribution of GPER increased,indicating that GPER was activated in T-47DTR-resistant cells compared with the control group; Compared with OHT,the use of G15(5 μmol·L-1)and OHT significantly reduced the expression of GPER.(3)GPER inhibitor G15 could increase the apoptotic rate of T-47DTR-resistant cells while down-regulating the anti-apoptotic protein Bcl-2 and up-regulating the expression of pro-apoptotic proteins Bax,cleaved caspase-3,cleaved caspase-9. Conclusions The GPER inhibitor G15 increases the apoptosis of T-47DTR cells and restores the sensitivity of drug-resistant cells to tamoxifen.

Clinical and radiologic outcomes after tendon insertion medialized repair of large-to-massive rotator cuff tears / 中国修复重建外科杂志

OBJECTIVE@#To evaluate the effectiveness of tendon insertion medialized repair in treatment of large-to-massive rotator cuff tears (L/MRCT).@*METHODS@#The clinical and imaging data of 46 L/MRCT patients who underwent arthroscopic insertion medialized repair between October 2015 and June 2019 were retrospectively analyzed. There were 26 males and 20 females with an average age of 57.7 years (range, 40-75 years). There were 20 cases of large rotator cuff tears and 26 cases of massive rotator cuff tears. Preoperative imaging evaluation included fatty infiltration (Goutallier grade), tendon retraction (modified Patte grade), supraspinatus tangent sign, acromiohumeral distance (AHD), and postoperative medializaiton length and tendon integrity. The clinical outcome was evaluated by visual analogue scale (VAS) score, American Society for Shoulder and Elbow Surgery (ASES) score, shoulder range of motion (including anteflexion and elevation, lateral external, and internal rotation) and anteflexion and elevation muscle strength before and after operation. The patients were divided into two groups (the intact tendon group and the re-teared group) according to the integrity of the tendon after operation. According to the medializaiton length, the patients were divided into group A (medialization length ≤10 mm) and group B (medialization length >10 mm). The clinical function and imaging indexes of the patients were compared.@*RESULTS@#All patients were followed up 24-56 months, with an average of 31.8 months. At 1 year after operation, MRI showed that the medializaiton length of supraspinatus tendon was 5-15 mm, with an average of 10.26 mm, 33 cases in group A and 13 cases in group B. Eleven cases (23.91%) had re-teared, including 5 cases (45.45%) of Sugaya type Ⅳ and 6 cases (54.55%) of Sugaya type Ⅴ. At last follow-up, the VAS score, ASES score, shoulder anteflexion and elevation range of motion, lateral external rotation range of motion, and anteflexion and elevation muscle strength significantly improved when compared with those before operation ( P<0.05); there was no significant difference in internal rotation range of motion between pre- and post-operation ( P>0.05). The Goutallier grade and modified Patte grade of supraspinatus muscle in the re-teared group were significantly higher than those in the intact tendon group, and the AHD was significantly lower than that in the intact tendon group ( P<0.05). There was no significant difference in other baseline data between the two groups ( P>0.05). Except that the ASES score of the intact tendon group was significantly higher than that of the re-teared group ( P<0.05), there was no significant difference in the other postoperative clinical functional indicators between the two groups ( P>0.05). There was no significant difference in the incidence of re-tear, VAS score, ASES score, range of motion of shoulder joint, and anteflexion and elevation muscle strength between group A and group B ( P>0.05).@*CONCLUSION@#Tendon insertion medialized repair may be useful in cases with L/MRCT, and shows good postoperative shoulder function. Neither tendon integrity nor medialization length shows apparent correlations with postoperative shoulder function.

mRNA Expression of Aquaporins in Human Luteinized Granulosa Cells from Different Diameter Follicles / 中山大学学报(医学科学版)

ObjectiveTo investigate the mRNA expression levels of various aquaporins （AQPs） in luteinized granulosa cells from follicles of different diameters. MethodsFrom March 25， 2022 to September 23， 2022 in our reproductive medicine center， 48 women undergoing in-vitro fertilization （IVF） were enrolled and divided into the antagonist group and the agonist group according to the ovarian stimulation protocol. Follicular fluid samples were collected on the day of oocyte pick-up and granulosa cells were extracted from follicles of different diameters： small （<13 mm）， medium （13~18 mm） and large （≥18 mm）. After RNA quantification， 22 cases （66 samples） were included for analysis and mRNA expression levels of AQPs were compared among the three follicle groups. ResultsThe mRNA expression of aquaporin 2 （AQP2） in luteinized granulosa cells increased with the increase of follicle diameter （linear trend P = 0.004） and the difference was statistically significant between two groups of large and small follicles （P = 0.017）. Statistical difference was found in the antagonist group （P = 0.049 6）， but not in the agonist group （P = 0.108）. ConclusionThe mRNA level of AQP2 in luteinized granulosa cells increases with the increase of follicle diameter and its expression is related to the ovarian stimulation protocol， suggesting that AQP2 may play a role in follicle growth and follicular fluid formation， and its mRNA expression level may be regulated by follicle stimulating hormone （FSH） and luteinizing hormone （LH）.

A facile and efficient synthesis approach of salidroside esters by whole-cell biocatalysts in organic solvents.

Salidroside, the main bioactive compound isolated from the plant source of Rhodiola rosea L, possesses broad-spectrum pharmacological activities, but suffers from the low cell membranes permeability and alimentary absorption due to its high polarity. Therefore, a whole-cell catalytic strategy for the synthesis of salidroside esters was explored to improve its lipophilicity. The results showed that Aspergillus oryzae demonstrated the highest biocatalytic activity among the microbial strains tested. For the synthesis of salidroside caprylate, the optimum conditions of reaction medium, Aspergillus oryzae amount, molar ratio of vinyl caprylate to salidroside and reaction temperature were acetone, 30 mg/ml, 10°C and 40°C, respectively. Under these conditions, the initial reaction rate was 15.36 mM/h, and substrate conversion and regioselectivity all reached 99%. Moreover, the results indicated that although various 6'-monoesters derivatives of salidroside were exclusively obtained with excellent conversions (96%-99%), the reaction rate varied greatly with different chain-length acyl donors. This study details an efficient and cost-effective biocatalytic approach for the synthesis of salidroside esters by using Aspergillus oryzae as a catalyst for the first time. Considering the whole cell catalytic efficiency and operational stability, this strategy may provide a new opportunity to develop green industrial processes production for ester derivatives of salidroside and its analogues.

Integrative Transcriptomic and Phytohormonal Analyses Provide Insights into the Cold Injury Recovery Mechanisms of Tea Leaves.

Tea plant is susceptible to low temperature, while the cold injury recovery mechanisms of tea leaves are still unclear. Windbreak has an effective and gradient range of protecting tea plants. Tea plants with increasing cold damage degree have varying recovery status accordingly, which are the ideal objects for investigating the cold injury recovery mechanisms of tea leaves. Here, we investigated the transcriptome and phytohormone profiles of tea leaves with different cold injury degrees in recovery (adjacent to the windbreak), and the levels of chlorophylls, malondialdehyde, major phytohormones as well as the activities of peroxidase (POD) and superoxide dismutase (SOD) were also measured. The results showed the content of total chlorophylls and the activity of POD in mature tea leaves gradually decreased with the distance to windbreak, while SOD showed the opposite. The major phytohormones were highly accumulated in the moderately cold-injured tea leaves. The biosynthesis of abscisic acid (ABA) was enhanced in the moderate cold damaged tea leaves, suggesting that ABA plays an important role in the cold response and resistance of tea plants. The transcriptomic result showed that the samples in different rows were well discriminated, and the pathways of plant-pathogen interaction and flavonoid biosynthesis were enriched based on KEGG analysis. WRKY, GRAS and NAC were the top classes of transcription factors differentially expressed in the different cold-injured tea leaves. Thus, windbreak is effective to protect adjacent tea plants from cold wave, and phytohormones importantly participate in the cold injury recovery of tea leaves.

Influences of Serendipita indica and Dictyophorae echinovolvata on the Growth and Fusarium Wilt Disease Resistance of Banana.

Recently, many control methods have been tried and applied in the Fusarium wilt disease control of banana and have achieved definite progresses. In this study, by using 'Zhongjiao No.3' and 'Zhongjiao No.4' banana seedlings as materials, the effects of Serendipita indica and bamboo fungus (Dictyophorae echinovolvata) culture substrates on the growth and Fusarium wilt disease resistance of banana were investigated. Results showed that the plant height, leaf length, leaf width, root length and root thickness, aboveground part fresh weight, root fresh weight, and relative chlorophyll content and nitrogen content in leaves of banana seedlings colonized with S. indica were all greater than those of non-colonized controls, while these parameters of banana seedlings grown in nutrient soil containing D. echinovolvata culture substrates were significantly suppressed. Both S. indica non-colonized and colonized seedlings cultivated in nutrient containing 1/4 D. echinovolvata culture substrates showed much milder symptoms compared with those cultivated in normal nutrient soil, indicating that the addition of bamboo fungus substrates to the soil can enhance the Fusarium wilt resistance of banana. The results obtained in this study can provide a basis for the application of S. indica and bamboo fungus in the prevention and control of banana Fusarium wilt disease.

Limited Recognition of Highly Conserved Regions of SARS-CoV-2.

Understanding the immune response to severe acute respiratory syndrome coronavirus (SARS-CoV-2) is critical to overcome the current coronavirus disease (COVID-19) pandemic. Efforts are being made to understand the potential cross-protective immunity of memory T cells, induced by prior encounters with seasonal coronaviruses, in providing protection against severe COVID-19. In this study we assessed T-cell responses directed against highly conserved regions of SARS-CoV-2. Epitope mapping revealed 16 CD8+ T-cell epitopes across the nucleocapsid (N), spike (S), and open reading frame (ORF)3a proteins of SARS-CoV-2 and five CD8+ T-cell epitopes encoded within the highly conserved regions of the ORF1ab polyprotein of SARS-CoV-2. Comparative sequence analysis showed high conservation of SARS-CoV-2 ORF1ab T-cell epitopes in seasonal coronaviruses. Paradoxically, the immune responses directed against the conserved ORF1ab epitopes were infrequent and subdominant in both convalescent and unexposed participants. This subdominant immune response was consistent with a low abundance of ORF1ab encoded proteins in SARS-CoV-2 infected cells. Overall, these observations suggest that while cross-reactive CD8+ T cells likely exist in unexposed individuals, they are not common and therefore are unlikely to play a significant role in providing broad preexisting immunity in the community. IMPORTANCE T cells play a critical role in protection against SARS-CoV-2. Despite being highly topical, the protective role of preexisting memory CD8+ T cells, induced by prior exposure to circulating common coronavirus strains, remains less clear. In this study, we established a robust approach to specifically assess T cell responses to highly conserved regions within SARS-CoV-2. Consistent with recent observations we demonstrate that recognition of these highly conserved regions is associated with an increased likelihood of milder disease. However, extending these observations we observed that recognition of these conserved regions is rare in both exposed and unexposed volunteers, which we believe is associated with the low abundance of these proteins in SARS-CoV-2 infected cells. These observations have important implications for the likely role preexisting immunity plays in controlling severe disease, further emphasizing the importance of vaccination to generate the immunodominant T cells required for immune protection.

Genome-wide identification of FAD gene family and their contributions to the temperature stresses and mutualistic and parasitic fungi colonization responses in banana.

Fatty acid desaturase (FAD) plays important roles in plant growth and development and plant defense processes. In this study, we identified 27 MaFAD genes from the banana genome. According to the amino acid sequence similarities, their encoded proteins could be classified into five subfamilies. This classification is consistently supported by their gene and protein structures, conserved motifs and subcellular localizations. Segmental duplication events were found to play predominant roles in the MaFAD gene family expansion. Thirty miRNAs targeting MaFADs were identified and many hormone- and stress-responsive cis-acting elements and transcription factor binding sites (TFBSs) were identified in their promoters, indicating that the MaFADs expression regulation was very complicated. Gene expression analysis showed that some MaFADs showed significant differential expression in response to high and low temperature. FocTR4 influenced greatly the expression of several MaFADs and greatly induced the fatty acid (FA) accumulations in roots. Although S. indica showed no significant influence on the expression of most MaFADs, it could greatly alleviate the influence of FocTR4 on several MaFADs and FA biosynthesis. Our study revealed that MaFADs contributed greatly to the responses of high and low temperature stresses and mutualistic and parasitic fungi colonization in banana.

Correlation of plasma prolactin and cortisol with vasovagal syncope in children / 中华实用儿科临床杂志

Objective:To investigate the changes of plasma prolactin (PRL) and cortisol (Cor) in the head up tilt test (HUT) in children with vasovagal syncope (VVS), and their correlation with VVS.Methods:From May 2019 to May 2020, 75 children diagnosed as VVS through positive HUT in the Children′s Hospital, Capital Institute of Pediatrics were retrospectively recruited as VVS group, while 29 healthy children with negative HUT during the same period were collected in healthy control group.Heart rate (HR) and blood pressure [systolic and diastolic blood pressure (SBP, DBP)] were monitored using a noninvasive continuous blood pressure monitor.The changes of HR, SBP and DBP were analyzed and their differences between the supine position and positive reaction of HUT were compared.The contents of PRL and Cor in the supine position and positive reaction of HUT were measured using the electrochemiluminescence, and their changes (ΔPRL and ΔCor) were calculated.Differences between groups were analyzed by the two-tailed Student′s t-test or the Mann- Whitney test.Receiver operating characteristic (ROC) curves were plotted to analyze the predictive value of ΔPRL on VVS. Results:There were no significant differences in the age, gender, body mass index, blood electrolyte, syncope frequency and syncope course between VVS group and healthy control group (all P>0.05). There was no significant difference in syncope frequency and course of syncope among subtypes of VVS group (vasodepressor syncope, mixed syncope, cardioinhibitory syncope)(all P>0.05). Compared with healthy control group, PRL after HUT was significantly higher in VVS group[36.23 (22.08, 61.97) μg/L vs.11.47 (8.00, 23.25 ) μg/L, Z=-5.40, P<0.01]. Both ΔPRL [25.36( 9.92, 48.93) μg/L vs.-0.10(- 2.67, 9.32) μg/L, Z=-5.39, P<0.01] and ΔCor [(84.4±43.6) μg/L vs.(57.6±64.6) μg/L, t=-2.44, P<0.05 ] were significantly higher in VVS group than those of healthy control group.PRL at HUT positive reaction was negatively correlated with SBP and DBP ( r=- 0.46, -0.45, all P<0.01). In VVS group, PRL at HUT positive reaction was negatively correlated with SBP ( r=-0.38, -0.24, all P<0.05). In VVS group, ΔCor after HUT was negatively correlated with SBP ( r=-0.25, P<0.05). ROC curves revealed that the cut-off value of ΔPRL in predicting HUT was 4.03 μg/L, with the sensitivity of 89.3% and specificity of 72.4%. Conclusions:Plasma PRL and Cor increase during syncope in VVS children, and plasma PRL is correlated with blood pressure drop.The increased plasma level of PRL in VVS children with positive HUT is correlated with blood pressure, and ΔCor is correlated with SBP.Plasma PRL and Cor may be involved in the pathogenesis of VVS and ΔPRL presents the diagnostic potential of VVS in children.

Expression and role of the TRPC family in TGF-β1-induced calcium influx in podocytes / 生理学报

The TRPC family consists of multiple important cationic channels in mammals that participate in a variety of physiological and pathological processes. Our previous studies have shown that transforming growth factor-β1 (TGF-β1) increases the expression of TRPC6 in podocytes, but the roles of other members of the TRPC family in podocytes require further investigation. In this study, we investigated the effect of TGF-β1 on the expression of the TRPC family and the role of the TRPC family in the changes of the intracellular Ca2+ concentration ([Ca2+]i) in podocytes induced by TGF-β1. The model of podocyte injury was established by treatment with TGF-β1 in immortalized glomerular podocytes (MPC5) in vitro. qRT-PCR and Western blot were used to detect the effect of TGF-β1 on the mRNA and protein expression of each TRPC family member. After the expression of each TRPC family member was knocked down by a siRNA-based approach and blocked by SKF96365, respectively, free cytosolic Ca2+ was measured using the fluorescent Ca2+ indicator Fluo-3/AM, and the dynamic change of [Ca2+]i in podocytes was detected by a dynamic high-speed calcium imaging system. The results showed that TGF-β1 increased the protein expression of TRPC1/3/6 in podocytes, but had no effects on the protein expression of TRPC4. The protein expression levels of TRPC5/7 were only affected by 4 ng/mL and 8 ng/mL TGF-β1, respectively. TGF-β1 increased TRPC1/3/6 mRNA levels in podocytes, however had no effects on TRPC4/5/7 mRNA. TGF-β1 significantly increased [Ca2+]i in podocytes. Knockdown of TRPC1/4/5/7 in podocytes had no significant effect on the [Ca2+]i induced by TGF-β1, but TRPC3/6 knockdown significantly decreased the [Ca2+]i. There was no significant difference in the [Ca2+]i between the TRPC6 siRNA-treated group and SKF96365-treated group, but the [Ca2+]i of the TRPC3 siRNA-treated group was significantly higher than that of SKF96365-treated group. These results demonstrate that TGF-β1 increases the expression of the TRPC1/3/6 in podocytes. TGF-β1 increases [Ca2+]i in podocytes, which is dependent on the TRPC3/6 expression. Our results also suggest that the effect of TRPC6 on [Ca2+]i in podocytes may be greater than that of TRPC3.