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BackgroundLignin is a key component of the secondary cell wall of plants, providing mechanical support and facilitating water transport as well as having important impact effects in response to a variety of biological and abiotic stresses.ResultsIn this study, we identified 104 genes from ten enzyme gene families related to lignin biosynthesis in Musa acuminata genome and found the number of MaCOMT gene family was the largest, while MaC3Hs had only two members. MaPALs retained the original members, and the number of Ma4CLs in lignin biosynthesis was significantly less than that of flavonoids. Segmental duplication existed in most gene families, except for MaC3Hs, and tandem duplication was the main way to expand the number of MaCOMTs. Moreover, the expression profiles of lignin biosynthesis genes during fruit development, postharvest ripening stages and under various abiotic and biological stresses were investigated using available RNA-sequencing data to obtain fruit ripening and stress response candidate genes. Finally, a co-expression network of lignin biosynthesis genes was constructed by weighted gene co-expression network analysis to elucidate the lignin biosynthesis genes that might participate in lignin biosynthesis in banana during development and in response to stresses.ConclusionThis study systematically identified the lignin biosynthesis genes in the Musa acuminata genome, providing important candidate genes for further functional analysis. The identification of the major genes involved in lignin biosynthesis in banana provides the basis for the development of strategies to improve new banana varieties tolerant to biological and abiotic stresses with high yield and high quality.

The basic helix−loop−helix (bHLH) proteins are a superfamily of transcription factors (TFs) that can bind to specific DNA target sites, playing a central role in a wide range of metabolic, physiological, and developmental processes in higher organisms. However, no systemic analysis of bHLH TFs has been reported in banana, a typical climacteric fruit in tropical and subtropical regions. In our study, 259 MabHLH TF genes were identified in the genome of Musa acuminata (A genome), and phylogenetic analysis indicated that these MabHLHs could be classified into 23 subfamilies with the bHLHs from rice and Arabidopsis. The amino acid sequences of the bHLH domain in all MabHLH protein sequences were quite conserved, especially Arg-12, Arg-13, Leu-23, and Leu-79. Distribution mapping results showed that 258 MabHLHs were localized on the 11 chromosomes in the M. acuminata genome. The results indicated that 40.7% of gene duplication events were located in collinear fragments, and segmental duplications might have played a key role in the expansion of MabHLHs. Moreover, the expression profiles of MabHLHs in different fruit development and ripening stages and under various abiotic and biotic stresses were investigated using available RNA-sequencing data to obtain fruit development, ripening-specific, and stress-responsive candidate genes. Finally, a co-expression network of MabHLHs was constructed by weighted gene co-expression network analysis to elucidate the MabHLHs that might participate in important metabolic biosynthesis pathways in banana during development and the response to stress. A total of 259 MabHLHs were identified, and their sequence features, conserved domains, phylogenetic relationships, chromosomal distributions, gene duplications, expression profiles, and co-expression networks were investigated. This study systematically identified the MabHLHs in the M. acuminata genome at the genome-wide level, providing important candidate genes for further functional analysis. These findings improve our understanding of the molecular basis of developmental and stress tolerance in an important banana cultivar.

BackgroundTricuspid annuloplasty is increasingly performed during left heart valve surgery, but the long‐term clinical outcome postoperatively is not satisfactory. The aim of this study was to determine whether residual pulmonary hypertension (PHT) contributes to the adverse outcome. Methods and ResultsOne‐hundred thirty‐seven patients (age 61±11 years; men, 30%) who underwent tricuspid annuloplasty during left‐side valve surgery were enrolled. The mean pulmonary artery systolic pressure before surgery was 49±13 mm Hg and 32±15 mm Hg following surgery. Patients were divided into 3 groups according to postoperative pulmonary artery systolic pressure: no residual PHT (n=78, 57%), mild residual PHT (n=43, 31%), or significant residual PHT (n=16, 12%). A preoperative larger right ventricular (RV) geometry and tricuspid valve tethering area were associated with mild or significant residual PHT. A total of 24 adverse events (20 heart failures and 4 cardiovascular deaths) occurred during a median follow‐up of 25 months. Kaplan–Meier survival curve demonstrated that patients with significant residual PHT had the highest percentage of adverse events followed by those with mild residual PHT. Patients with no residual PHT had a very low risk of adverse events. Multivariable Cox regression analysis revealed that both mild (hazard ratio=4.94; 95% CI =1.34–18.16; P=0.02) and significant residual PHT (hazard ratio=8.67; 95% CI =2.43–30.98; P

Objective: To observe the effect of vitaminD3 on airway inflammation and osteopontin (OPN) expression on cough variant asthma (CVA) models. Methods: SD rats were randomly divided into blank group, model group and treatment group, each group with 10 rats. The CVA model was induced by intraperitoneal injection combined with aerosolized ovalbumin (OVA), the treatment group was given 100 mg / ml of vitaminD3 30 minutes before challenge by administered orally. Airway hyperreaction were measured by airway resistance after inhalation of acetylcholine (Ach). Wright-Gimsa staining was used to observe the inflammatory cells in bronchoalveolar lavage fluid (BALF). HE and PAS were used to observe the morphological changes of lung tissue. OPN expression was detected by immunohistochemistry. Results: 1) Airway hyperreaction: airway resistance after inhalation Ach in model group and treatment group were significantly higher than that in blank group (P <0.01), airway resistance in treatment group were lower than that in model group (P <0.01); 2) Classification of inflammatory cells: The percentage of macrophages, lymphocytes, neutrophils, and eosinophils in the BALF of the model group and the treatment group were increased compared with the blank group (P <0.01),furthermore, the number of treatment group were lower than the model group(P <0.05); 3) Morphological changes of lung tissue: a large amount of inflammatory cells and goblet cell proliferation were observed in the lung tissue of the model group, and these changes were slight in treatment group compared with model group; OPN expression in lung tissue: The expression of OPN in model and treatment group were increased compared with blank group (P <0.05), and the treatment group was lower than that of model group (P <0.05). The OPN content was positively correlated with the percentage of inflammatory cells in BALF (P < 0.05). Conclusions: Vitamin D3 can reduce airway hyperreaction and airway inflammation in CVA rats. The mechanism may be related to the intervention of OPN expression in lung tissue. [ABSTRACT FROM AUTHOR]

Objective: To investigate the clinical effect of ultra-low frequency repetitive transcranial magnetic stimulation on dysphagia in elderly patients with acute cerebral infarction and its impact on quality of life. Methods: 60 elderly patients with dysphagia caused by acute cerebral infarction were randomly divided into rTMS group and control group, 30 cases in each group. Both groups received routine drug therapy and swallowing function training. rTMS group was additionally treated by ultra-low frequency (10mHZ) repetitive transcranial magnetic stimulation for 14 days. The changes of NIHSS score and ADL score and NSE serum level and Wa Tian drinking water experiment and Fujishima Ichiro dysphagia scale score and SWAL-QOL score and SF-36 score were observed between the two groups before and after treatment. The clinical effect was evaluated by Wa Tian drinking water experiment. Results: After treatment, The clinical effective rate in rTMS group was significantly higher compared with that in the control group (P < 0.05), NIHSS score and serum NSE level were significantly lower compared with the control group (P < 0.05), ADL score and Fujishima Ichiro dysphagia score and SWAL-QOL score and SF-36 scores were significantly higher compared with the control group (P < 0.05). After treatment, SF-36 total score(or SWAL-QOL Score) was negatively correlated with NSE serum level and NIHSS score, which was positively correlated with ADL score and Fujishima Ichiro dysphagia scale score score. Conclusion: Ultra-low frequency rTMS therapy can reduce NSE level, effectively improve dysphagia in elderly patients with acute cerebral infarction and significantly improve the elderly patients' life quality. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of low-frequency rTMS combined with fasudil on neurological function in patients with acute cerebral infarction and its mechanism. Method:120 patients with acute cerebral infarction admitted from January 2016 to January 2019 were randomly divided into four groups: control group (n = 30), fasudil group (n = 30), rTMS group (n = 30), fasudil + rTMS group (n = 30). The changes of NIHSS score, ADL score, serum GAP- 43, serum RhoA and serum ROCK-II were observed and recorded before and after treatment. Results: The ADL scores and serum GAP-43 levels of the four groups after treatment were higher than those before treatment (P < 0.05); the NIHSS scores, serum RhoA and serum ROCK-II levels of the four groups after treatment were lower than those before treatment (P < 0.05); After treatment, ADL score and serum GAP-43 level in fasudil+rTMS group were higher than those in other three groups (P < 0.05); After treatment, NIHSS score, serum RhoA and serum ROCK-II levels in fasudil+rTMS group were lower than those in other three groups (P < 0.05). After treatment, NIHSS score was positively correlated with RhoA and ROCK-II content, negatively correlated with GAP-43 content and ADL score. Conclusions: Low-frequency rTMS combined with fasudil in the treatment of acute cerebral infarction can significantly improve neurological deficits, improve daily living ability, promote axonal remodeling and regeneration. It may be one of its mechanisms by increasing the expression of GAP-43 in serum and reducing the expression levels of RhoA and ROCK-II in serum. It has high clinical value. [ABSTRACT FROM AUTHOR]

A non-dipper pattern of high blood pressure is associated with increased risk of organ damage and cardiovascular disease in patients with hypertension. The aim of the study was to evaluate the left ventricular (LV) remodeling and function and arterial stiffness in a dipper/non-dipper pattern of high blood pressure in patients with hypertension. A total of 183 hypertensive patients with no history of adverse cardiovascular events were divided into two groups based on 24 hours ambulatory blood pressure monitoring (ABPM): 66 patients with a dipper pattern and 117 patients with non-dipper pattern. Detailed transthoracic echocardiogram was performed and analyzed with advance speckle tracking 3-orthogonal direction strain analysis to assess LV systolic function and tissue Doppler-derived E/E' for LV diastolic function assessment. Cardio ankle vascular index (CAVI) was used to evaluate arterial stiffness. Compared with patients with dipper hypertension, those with non-dipper hypertension had increased LV mass index, higher prevalence of eccentric and concentric LV hypertrophy, more impaired LV diastolic and systolic function and peripheral arterial stiffness. Multivariable analysis revealed that a non-dipper pattern was independently associated with LV systolic dysfunction evaluated by speckle tracking-derived strain analysis. In conclusion, a non-dipper pattern of hypertension is an independent risk factor for LV systolic dysfunction. Treatment that could reverse this non-dipper pattern may reduce cardiac damage in these patients. [ABSTRACT FROM AUTHOR]

Background: Patients with type 2 diabetes mellitus (T2DM) are at high risk for cardiovascular events. The aim of the study was to assess whether global longitudinal strain (GLS) provides prognostic value in these patients. Methods: A total of 247 T2DM patients without history of cardiovascular complications and participated in the CDATS study were prospectively enrolled. Left ventricular (LV) systolic function was assessed by LV ejection fraction and speckle tracking derived LV systolic GLS. Diastolic function was assessed by E/E' ratio deined as the passive trans-mitral LV inflow velocity to tissue Doppler imaging velocity of the medial mitral annulus. Cardiovascular event included acute coronary syndrome, cerebrovascular stroke, hospitalization for heart failure and cardiovascular death. Results: A total of 18 cardiovascular events occurred during a median follow-up duration of 33 months. Both E/E' ratio [hazard ratio (HR) 1.15, P < 0.01] and GLS (HR 1.39, P < 0.01) were independently associated with cardiovascular events. Importantly, GLS provided incremental prognostic information in addition to clinical data, HbA1c and E/E' ratio (Chi square 77.46, P = 0.04). Receiver-operator characteristic curve analysis demonstrated that E/E' ratio [area under curve (AUC) 0.66, P = 0.03] and GLS (AUC 0.72, P < 0.01) were strong predictors of cardiovascular events. Kaplan-Meier analysis showed that patients with E/E' > 13.6 or GLS > -17.9 % were associated with cardiovascular events. The presence of either a high E/E' ratio or an impaired GLS provides an excellent negative predictive value of cardiovascular events in these patients. Conclusions: In T2DM patients with no history of cardiovascular disease, impaired GLS was associated with cardiovascular events and provided incremental prognostic value. [ABSTRACT FROM AUTHOR]

Background: Type 2 diabetes mellitus (T2DM) complicated by retinopathy is associated with altered left ventricular (LV) structure and resting myocardial dysfunction unlike T2DM without retinopathy. The myocardial response to stress has not been compared in patients with and without diabetic retinopathy. The aim of this retrospective study was to determine the relationship between retinopathy and myocardial function in patients with T2DM at rest and during exercise echocardiography. Methods: 134 patients with T2DM and no evidence of underlying coronary artery disease were recruited. All patients underwent retinal photography to screen for diabetic retinopathy, and resting and exercise echocardiography. Resting echocardiography was analyzed by conventional echocardiographic parameters and speckle tracking derived global longitudinal strain (GLS). Exercise echocardiography parameters included diastolic function reserve index (DFRI) and stress GLS. Results: The mean age of participants was 60 years and 49 % were male. Diabetic retinopathy was identified in 43 patients (32 %). Resting echocardiography revealed that those with diabetic retinopathy had a higher prevalence of impaired diastolic function, higher E/E' ratio (LV filling pressures) and impaired resting GLS compared with those without. Exercise echocardiography revealed that those with diabetic retinopathy also had more impaired DFRI and stress GLS. Multivariable analysis showed that the presence of diabetic retinopathy was independently associated with high resting E/E', diastolic dysfunction grade, impaired resting GLS, low DFRI and impaired stress GLS. Conclusions: In conclusion, the presence of diabetic retinopathy was independently associated with impaired resting myocardial function (diastolic and systolic function) and myocardial function during stress (evaluated by DFRI and stress GLS). [ABSTRACT FROM AUTHOR]

The banana, a typical climacteric fruit, undergoes a postharvest ripening process followed by a burst in ethylene production that signals the beginning of the climacteric period. Postharvest ripening plays an important role in improving the quality of the fruit as well as limiting its shelf life. To investigate the role of glutamate decarboxylase (GAD) in climacteric ethylene biosynthesis and fruit ripening in postharvest banana, a GAD gene was isolated from banana, designated MuGAD. Coincidently with climacteric ethylene production, MuGAD expression as well as the expression of the genes encoding the Musa 1-aminocyclopropane-1-carboxylate synthase (MaACS1) and Musa 1-aminocyclopropane-1-carboxylate oxidase (MaACO1) greatly increased during natural ripening and in ethylene-treated banana. Moreover, ethylene biosynthesis, ripening progress, and MuGAD, MaACS1, and MaACO1 expression were enhanced by exogenous ethylene application and inhibited by 1-methylcyclopropene (1-MCP). Taken together, our results suggested that MuGAD is involved in the fruit ripening process in postharvest banana. [ABSTRACT FROM AUTHOR]

A full-length cDNA isolated from banana (Musa acuminata L. AAA group) fruit was named MaMDH, containing an open reading frame encoding 332 amino acids that represents the gene for cytoplasmic malic dehydrogenase (MDH). Sequence analysis showed that MaMDH shares high similarity with MDHs from castor bean (XP_002533463), tobacco (CAC12826), peach (AAL11502), and chickpeas (CAC10208). Real-time quantitative polymerase chain reaction (PCR) analysis of MaMDH spatial expression showed that it was expressed in all organs examined: roots, rhizomes, leaves, flowers, and fruits. The expression was the highest in flowers followed by the fruits and roots, whereas the rhizomes and leaves displayed the lowest expression levels. Real-time quantitative PCR revealed that MaMDH exhibited differential expression patterns in post-harvest banana fruits correlating with ethylene biosynthesis. In naturally ripened banana fruits, MaMDH expression was in accordance with ethylene biosynthesis. In accordance, for banana fruits treated with the ethylene analog 1-methylclopropene (1-MCP), MaMDH expression levels were inhibited and remained constant. After treatment with ethylene, MaMDH expression in banana fruits significantly increased with ethylene biosynthesis and peaked 3 days after harvest, which was 11 days earlier than that in naturally ripened banana fruits. These results suggest that MaMDH expression is induced by ethylene to regulate post-harvest banana fruits ripening. [ABSTRACT FROM AUTHOR]