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1.

Background

2D strain imaging of the left atrium (LA) is a new echocardiographic method which allows us to determine contractile, conduit and reservoir functions separately. This method is particularly useful when changes are subtle and not easily determined by traditional parameters, as it is in arterial hypertension and atrial fibrillation (AF). The aims of our study were: to determine LA contractile, conduit and reservoir function by 2D strain imaging in patients with mild arterial hypertension and paroxysmal AF; to assess LA contractile, conduit and reservoir functions’ relation with LV diastolic dysfunction (DD) parameters.

Methods

LA contractile, conduit and reservoir functions together with echocardiographic signs of LV DD were assessed in 63 patients with arterial hypertension and paroxysmal AF. Patients were grouped according to number of signs showing LV DD (annular e’ velocity: septal e’?<?7 cm/s, lateral e’?<?10 cm/s, average E/e’ ratio?>?14, LA volume index >?34 ml/m2, peak tricuspid regurgitation velocity?>?2.8 m/s) present. Number of patients with 0 signs – 17, 1 sign – 26, 2 signs – 19. Contractile, conduit and reservoir functions were compared between the groups.

Results

Mean contractile, conduit and reservoir strains in all the patients were???14.14 (± 5.83) %, 15.98 (± 4.85) % and 31.03 (± 7.64) % respectively. Contractile strain did not differ between the groups. Conduit strain was higher in patients with 0 signs compared with other groups (p =?0.016 vs 1 sign of LV DD and p =?0.001 vs 2 signs of LV DD). Reservoir strain was higher in patients with 0 signs compared with other groups (p =?0.014 vs 1 sign of LV DD and p <?0.001 vs 2 signs of LV DD).

Conclusions

The patients with paroxysmal AF and primary arterial hypertension have decreased reservoir, conduit and pump LA functions even in the absence of echocardiographic signs of LV DD. With increasing number of parameters showing LV DD, LA conduit and reservoir functions decrease while contractile does not change. LA conduit and reservoir functions decrease earlier than the diagnosis of LV DD can be established according to the guidelines in patients with primary arterial hypertension and AF.
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2.

Background

Diabetes and hypertension increase arterial stiffness and cardiovascular events in all societies studied so far; sub-Saharan African studies are sparse. We investigated factors affecting arterial function in Ghanaians with diabetes, hypertension, both or neither.

Method

Testing the hypothesis that arterial stiffness would progressively increase from controls to multiply affected patients, 270 participants were stratified into those with diabetes or hypertension only, with both, or without either. Cardio-ankle vascular index (CAVI), heart–ankle pulse wave velocity (haPWV), aortic PWV (PWVao) by Arteriograph, aortic and brachial blood pressures (BP), were measured.

Results

In patients with both diabetes and hypertension compared with either alone, values were higher of CAVI (mean?±?SD, 8.3?±?1.2 vs 7.5?±?1.1 and 7.4?±?1.1 units; p?<?0.05), PWVao (9.1?±?1.4 vs 8.7?±?1.9 and 8.1?±?0.9 m/s; p?<?0.05) and haPWV (8.5?±?1 vs 7.9?±?1 and 7.2?±?0.7 m/s; p?<?0.05) respectively. In multivariate analysis, age, having diabetes or hypertension and BMI were independently associated with CAVI in all participants (β?=?0.49, 0.2, 0.17 and -0.2 units; p?<?0.01, respectively). Independent determinants of PWVao were heart rate, systolic BP and age (β?=?0.42, 0.27 and 0.22; p?<?0.01), and for haPWV were systolic BP, age, BMI, diabetes and hypertension status (β?=?0.46, 0.32, -0.2, 0.2 and 0.11; p?<?0.01).

Conclusion

In this sub-Saharan setting with lesser atherosclerosis than the western world, arterial stiffness is significantly greater in patients with coexistent diabetes and hypertension but did not differ between those with either diabetes or hypertension only. Simple, reproducibly measured PWV/CAVI may offer effective and efficient targets for intervention.
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3.

Background

Left ventricular (LV) diastolic dysfunction occurs earlier in the ischemic cascade than LV systolic dysfunction and electrocardiographic changes. Diastolic wall strain (DWS) has been proposed as a marker of LV diastolic stiffness. Therefore, the objectives of this study were to define the relationship between DWS and coronary revascularization and to evaluate other echocardiographic parameters in patients with stable angina who were undergoing coronary angiography (CAG).

Methods

Four hundred forty patients [mean age: 61?±?10; 249 (57%) men] undergoing CAG and with normal left ventricular systolic function without regional wall motion abnormalities were enrolled. Among them, 128 (29%) patients underwent revascularization (percutaneous intervention: 117, bypass surgery: 11). All patients underwent echocardiography before CAG and the DWS was defined using posterior wall thickness (PWT) measurements from standard echocardiographic images [DWS?=?PWT(systole)-PWT(diastole)/PWT(systole)].

Results

Patients who underwent revascularization had a significantly lower DWS than those who did not (0.26?±?0.08 vs. 0.38?±?0.09, p?<?0.001). Age was comparable between the two groups (61?±?9 vs. 60?±?11, p?=?0.337), but the proportion of males was significantly higher among patients who underwent revascularization (69 vs. 52%, p?=?0.001). The LV ejection fraction was similar but slightly decreased (60.9?±?5.7 vs. 62.4?±?6.2%, p?=?0.019) and the E/E’ ratio was elevated (10.3?±?4.0 vs. 9.0?±?3.1, p?<?0.001) among patients who underwent revascularization. In multiple regression analysis, lower DWS was an independent predictor of revascularization (cut-off value: 0.34; sensitivity: 89%; AUC: 0.870; SE: 0.025; p?<?0.001).

Conclusion

DWS, a simple parameter that can be calculated from routine 2D echocardiography, is inversely associated with the presence of coronary artery disease and the need for revascularization.
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4.

Purpose

The use of cardiac magnetic resonance (CMR) analysis has increased in patients with hypertrophic cardiomyopathy (HCM). Quantification of left ventricular (LV) measures will be affected by the inclusion or exclusion of the papillary muscles as part of the LV mass, but the magnitude of effect and potential consequences are unknown.

Methods

We performed Cine-CMR in (1) clinical HCM patients (n?=?55) and (2) subclinical HCM mutation carriers without hypertrophy (n?=?14). Absolute and relative differences in LV ejection fraction (EF) and mass were assessed between algorithms with and without inclusion of the papillary muscles.

Results

Papillary muscle mass in group 1 was 6.6?±?2.5 g/m2 and inclusion of the papillary muscles resulted in significant relative increases in LVEF of 4.5?±?1.8?% and in LV mass of 8.7?±?2.6?%. For group 2 these figures were 4.0?±?0.9 g/m2, 3.8?±?1.0?% and 9.5?±?1.8?%, respectively. With a coefficient of variation of 4?%, this 9?% difference in LV mass during CMR follow-up will be considered a change, while in fact the exact same mass may have been assessed according to two different algorithms.

Conclusions

In clinical HCM patients, CMR quantification of important LV measures is significantly affected by inclusion or exclusion of the papillary muscles. In relative terms, the difference was similar in subjects without hypertrophy. This underscores a general need for a uniform approach in CMR image analysis.
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5.

Introduction

Swine dysentery caused by Brachyspira hyodysenteriae is a production limiting disease in pig farming. Currently antimicrobial therapy is the only treatment and control method available.

Objective

The aim of this study was to characterize the metabolic response of porcine colon explants to infection by B. hyodysenteriae.

Methods

Porcine colon explants exposed to B. hyodysenteriae were analyzed for histopathological, metabolic and pro-inflammatory gene expression changes.

Results

Significant epithelial necrosis, increased levels of l-citrulline and IL-1α were observed on explants infected with B. hyodysenteriae.

Conclusions

The spirochete induces necrosis in vitro likely through an inflammatory process mediated by IL-1α and NO.
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6.

Background

Long-term intensive training leads to morphological and mechanical changes in the heart generally known as “athlete’s heart”. Previous studies have suggested that the diastolic and systolic function of the ventricles is unaltered in athletes compared to sedentary.The purpose of this study was to investigate myocardial performance index (MPI) by pulsed wave Doppler (PWD) and by tissue Doppler imaging (TDI) in female elite athletes compared to sedentary controls.

Methods

The study consisted of 32 athletes (mean age 20 ± 2 years) and 34 sedentary controls (mean age 23 ± 2 years). MPI by PWD and TDI were measured in the left (LV) and right ventricle (RV) in both groups. Moreover, comparisons of MPI by the two methods and between the LV and RV within the two groups were made.

Results

There were no significant differences in MPI between athletes and controls (p > 0.05), whereas the LV had significantly higher MPI compared to RV (p < 0.001, in athletes and controls). The agreement and the correlation between the two methods measuring MPI showed low agreement and no correlation (athletes RV r = ?0.027, LV r = 0.12; controls RV r = 0.20, LV r = 0.30).

Conclusion

The global function of the LV and RV measured by MPI with PWD and TDI is similar in female athletes compared to sedentary controls. Conversely, both MPI by PWD and by TDI shows a significant difference between the LV and RV. However, the agreement and correlation between conventional methods of measuring MPI by PWD compared to MPI by TDI is very poor in both these populations.
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7.

Introduction

Botanicals containing iridoid and phenylethanoid/phenylpropanoid glycosides are used worldwide for the treatment of inflammatory musculoskeletal conditions that are primary causes of human years lived with disability, such as arthritis and lower back pain.

Objectives

We report the analysis of candidate anti-inflammatory metabolites of several endemic Scrophularia species and Verbascum thapsus used medicinally by peoples of North America.

Methods

Leaves, stems, and roots were analyzed by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) and partial least squares-discriminant analysis (PLS-DA) was performed in MetaboAnalyst 3.0 after processing the datasets in Progenesis QI.

Results

Comparison of the datasets revealed significant and differential accumulation of iridoid and phenylethanoid/phenylpropanoid glycosides in the tissues of the endemic Scrophularia species and Verbascum thapsus.

Conclusions

Our investigation identified several species of pharmacological interest as good sources for harpagoside and other important anti-inflammatory metabolites.
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8.

Introduction

Mass spectrometry imaging (MSI) experiments result in complex multi-dimensional datasets, which require specialist data analysis tools.

Objectives

We have developed massPix—an R package for analysing and interpreting data from MSI of lipids in tissue.

Methods

massPix produces single ion images, performs multivariate statistics and provides putative lipid annotations based on accurate mass matching against generated lipid libraries.

Results

Classification of tissue regions with high spectral similarly can be carried out by principal components analysis (PCA) or k-means clustering.

Conclusion

massPix is an open-source tool for the analysis and statistical interpretation of MSI data, and is particularly useful for lipidomics applications.
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9.

Background

Weaning stress affects the small intestine of piglets. MiR-146b is differentially expressed in suckling and weaned piglets. In this study, we evaluated the effects of miR-146b on cell viability, proliferation, and apoptosis in IPEC-J2 cells.

Results

Transfection with miR-146b mimics successfully increased miR-146b levels by 1000× (P?<?0.001). The over-expression of miR-146b significantly promoted the apoptosis (P?<?0.01) of IPEC-J2 cells, with no significant effects on cell viability or proliferation. MiR-146b suppressed the luciferase activity of the miR-TLR4-wt by 57% compared with the negative control, while mutation of the miR-146b binding site significantly blocked the suppressive effect (P?<?0.05). Western blot results showed that TLR4 levels decreased in IPEC-J2 cells transfected with miR-146b mimics (P?<?0.05).

Conclusions

The over-expression of miR-146b promotes IPEC-J2 cell apoptosis. TLR4 is a direct target of miR-146b in IPEC-J2 cells.

Reviewers

This article was reviewed by Eugene Berezikov and Jan B Hoek.
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10.

Background

Verheij syndrome is a rare microdeletion syndrome of chromosome 8q24.3 that harbors PUF60, SCRIB, and NRBP2 genes. Subsequently, loss of function mutations in PUF60 have been found in children with clinical features significantly overlapping with Verheij.

Case presentation

Here we present the first Chinese Han patient with a de novo nonsense variant (c.1357C?>?T, p.Gln453*) in PUF60 by clinical whole exome sequencing. The 5-year-old boy presents with dysmorphic facial features, intellectual disability, and growth retardation but without apparent cardiac, renal, ocular, and spinal anomalies.

Conclusions

Our finding contributes to the understanding of the genotype and phenotype in PUF60 related disorder.
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11.

Introduction

Cellulose microfibril is a major cell wall polymer that plays an important role in the growth and development of plants. The gene cellulose synthase A (CesA), encoding cellulose synthases, is involved in the synthesis of cellulose microfibrils. However, the regulatory mechanism of CesA gene expression is not well understood, especially during the early developmental stages.

Objective

To identify factor(s) that regulate the expression of CesA genes and ultimately control seedling growth and development.

Methods

The presence of cis-elements in the promoter region of the eight CesA genes identified in flax (Linum usitatissimum L. ‘Nike’) seedlings was verified, and three kinds of ethylene-responsive cis-elements were identified in the promoters. Therefore, the effect of ethylene on the expression of four selected CesA genes classified into Clades 1 and 6 after treatment with 10?4 and 10?3 M 1-aminocyclopropane-1-carboxylic acid (ACC) was examined in the hypocotyl of 4–6-day-old flax seedlings.

Results

ACC-induced ethylene either up- or down-regulated the expression of the CesA genes depending on the clade to which these genes belonged, age of seedlings, part of the hypocotyl, and concentration of ACC.

Conclusion

Ethylene might be one of the factors regulating the expression of CesA genes in flax seedlings.
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12.

Background

Almost all attempts to improve patient selection for cardiac resynchronization therapy (CRT) using echo-derived indices have failed so far. We sought to assess: the performance of homemade software for the automatic quantification of integral 3D regional longitudinal strain curves exploring left ventricular (LV) mechanics and the potential value of this tool to predict CRT response.

Methods

Forty-eight heart failure patients in sinus rhythm, referred for CRT-implantation (mean age: 65 years; LV-ejection fraction: 26%; QRS-duration: 160 milliseconds) were prospectively explored. Thirty-four patients (71%) had positive responses, defined as an LV end-systolic volume decrease ≥15% at 6-months. 3D–longitudinal strain curves were exported for analysis using custom-made algorithms. The integrals of the longitudinal strain signals (I L,peak) were automatically measured and calculated for all 17 LV-segments.

Results

The standard deviation of longitudinal strain peak (SDI L,peak ) for all 17 LV-segments was greater in CRT responders than non-responders (1.18% s?1 [0.96; 1.35] versus 0.83% s?1 [0.55; 0.99], p = 0.007). The optimal cut-off value of SDI L,peak to predict response was 1.037%.s?1. In the 18-patients without septal flash, SDI L,peak was significantly higher in the CRT-responders.

Conclusions

This new automatic software for analyzing 3D longitudinal strain curves is avoiding previous limitations of imaging techniques for assessing dyssynchrony and then its value will have to be tested in a large group of patients.
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13.

Introduction

Little is known about the association of urine metabolites with structural lesions in persons with diabetes.

Objectives

We examined the relationship between 12 urine metabolites and kidney structure in American Indians with type 2 diabetes.

Methods

Data were from a 6-year clinical trial that assessed renoprotective efficacy of losartan, and included a kidney biopsy at the end of the treatment period. Metabolites were measured in urine samples collected within a median of 6.5 months before the research biopsy. Associations of the creatinine-adjusted urine metabolites with kidney structural variables were examined by Pearson’s correlations and multivariable linear regression after adjustment for age, sex, diabetes duration, hemoglobin A1c, mean arterial pressure, glomerular filtration rate (iothalamate), and losartan treatment.

Results

Participants (n?=?62, mean age 45?±?10 years) had mean?±?standard deviation glomerular filtration rate of 137?±?50 ml/min and median (interquartile range) urine albumin:creatinine ratio of 34 (14–85) mg/g near the time of the biopsy. Urine aconitic and glycolic acids correlated positively with glomerular filtration surface density (partial r?=?0.29, P?=?0.030 and r?=?0.50, P?<?0.001) and total filtration surface per glomerulus (partial r?=?0.32, P?=?0.019 and r?=?0.43, P?=?0.001). 2-ethyl 3-OH propionate correlated positively with the percentage of fenestrated endothelium (partial r?=?0.32, P?=?0.019). Citric acid correlated negatively with mesangial fractional volume (partial r=-0.36, P?=?0.007), and homovanillic acid correlated negatively with podocyte foot process width (partial r=-0.31, P?=?0.022).

Conclusions

Alterations of urine metabolites may associate with early glomerular lesions in diabetic kidney disease.
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14.

Background

The study aimed at examining hypoxia-inducible factor (HIF)1α expression in adenocarcinomas and adenomas in bitches in regard to tumour malignancy grade, proliferation, apoptosis and vascularisation. Therefore, paraffin sections of 15 adenomas and 64 adenocarcinomas sampled from 79 dogs aged 6 to 16 years were analysed.

Results

A significantly higher HIF-1α expression was noted in adenocarcinomas in comparison to adenomas (P?<?0.0004). Moreover, HIF-1α expression in adenocarcinomas correlated positively with tumour malignancy grade (r?=?0.59, P?<?0.05), Ki-67 antigen expression (r?=?0.43; P?<?0.0005), TUNEL-positive cells (r?=?0.62, P?<?0001) and tumour vascularity measured by quantification of vessels characterized by the expression of von Willebrand Factor (r?=?0.57, P?<?0.05).

Conclusion

Results of this study indicate a similar biological role of HIF-1α in dogs and in humans, which may confirm suitability of the animal model in investigations on progression of tumours in humans.
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15.

Objective

The visceral sensitivity index (VSI) is a useful self-report measure of the gastrointestinal symptom-specific anxiety (GSA) of patients with irritable bowel syndrome (IBS). Previous research has shown that worsening GSA in IBS patients is related to the severity of GI symptoms, suggesting that GSA is an important endpoint for intervention. However, there is currently no Japanese version of the VSI. We therefore translated the VSI into Japanese (VSI-J) and verified its reliability and validity.

Material and methods

Participants were 349 university students aged 18 and 19 years and recruited from an academic class. We analyzed data from the VSI-J, Anxiety Sensitivity Index (ASI), Hospital Anxiety and Depression scale (HAD), and Irritable Bowel Syndrome Severity Index (IBS-SI). The internal consistency, stability, and factor structure of the VSI-J and its associations with anxiety, depression and severity measures were investigated.

Results

The factor structure of the VSI-J is unidimensional and similar to that of the original VSI (Cronbach’s α?=?0.93). Construct validity was demonstrated by significant correlations with ASI (r?=?0.43, p?<?0.0001), HAD-ANX (r?=?0.19, p?=?0.0003), and IBS-SI scores (r?=?0.45, p?<?0.0001). Furthermore, the VSI-J was a significant predictor of severity scores on the IBS-SI and demonstrated good discriminant (p?<?0.0001) and incremental (p?<?0.0001) validity.

Conclusion

These findings suggest that the VSI-J is a reliable and valid measure of visceral sensitivity.
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16.

Background

The aim of this study was to explore the characteristics and prognostic information of estrogen receptor-positive/progesterone receptor-negative (ER+/PR?) male breast cancer.

Methods

Using the US National Cancer Institute’s Surveillance, Epidemiology, and End Results database, we compared the demographics, clinical characteristics, and outcome of estrogen receptor-positive/progesterone receptor-positive (ER+/PR+) patients with ER+/PR? male breast cancer patients from 1990 to 2010. Two thousand three hundred twenty-two patients with ER+/PR+ tumors and 355 patients with ER+/PR? tumors were included in our study.

Results

ER+/PR? patients were younger (P?=?0.008) and more likely to be African American (P?<?0.001) while presented with higher histological grade (P?<?0.001), larger tumor size (P?=?0.010), and more invasion to the lymph nodes (P?=?0.034) and distant sites (P?<?0.001), thus later stage (P?=?0.001). Despite higher chance of receiving chemotherapy (51.0% vs 36.5%, P?<?0.001), ER+/PR? patients experienced significantly worse breast cancer-specific survival (BSCC) (P?<?0.001) and shorter overall survival (OS) (P?=?0.003). Multivariate Cox model confirmed that tumor size, lymph node invasion, metastasis, and surgery were independent prognostic factors of both BSCC and OS for ER+/PR? male breast cancer. Age at diagnosis and chemotherapy were significantly associated with OS but not with BSCC.

Conclusion

ER+/PR? male breast cancer was more aggressive and experienced shorter survival than ER+/PR+ patients. The prognosis was mainly associated with tumor size, lymph node invasion, metastasis, and surgery.
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17.

Background

Deteriorated arterial function and high incidence of cardiovascular events characterise diabetes mellitus. Metformin and recent antidiabetic drugs, SGLT2 inhibitors, reduce cardiovascular events. We explored the possible effects of empagliflozin’s effect on top of metformin treatment on endothelial function and arterial stiffness parameters in type 1 diabetes mellitus (T1DM) patients.

Methods

Forty T1DM patients were randomised into three treatment groups: (1) empagliflozin (25 mg daily), (2) metformin (2000 mg daily) and (3) empagliflozin/metformin (25 mg daily and 2000 mg daily, respectively). The fourth group received placebo. Arterial function was assessed at inclusion and after 12 weeks treatment by: endothelial function [brachial artery flow-mediated dilation (FMD), reactive hyperaemia index (RHI)], arterial stiffness [pulse wave velocity (PWV) and common carotid artery stiffness (β-stiffness)]. For statistical analysis one-way analysis of variance with Bonferroni post-test was used.

Results

Empagliflozin on top of metformin treatment significantly improved endothelial function as did metformin after 12 weeks of treatment: FMD [2.6-fold (P?<?0.001) vs. 1.8-fold (P?<?0.05)] and RHI [1.4-fold (P?<?0.01) vs. 1.3-fold (P?<?0.05)]. Empagliflozin on top of metformin treatment was superior to metformin in improving arterial stiffness parameters; it significantly improved PWV and β-stiffness compared to metformin [by 15.8% (P?<?0.01) and by 36.6% (P?<?0.05), respectively]. Metformin alone did not influence arterial stiffness.

Conclusion

Empagliflozin on top of metformin treatment significantly improved arterial stiffness compared to metformin in T1DM patients. Endothelial function was similarly improved in all treatment groups. Empagliflozin seems to possess a specific capacity to decrease arterial stiffness, which could support its cardioprotective effects observed in large clinical studies.Trial registration Clinical trial registration: NCT03639545
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18.

Background

Previous research suggested that single gene expression might be correlated with acute myeloid leukemia (AML) survival. Therefore, we conducted a systematical analysis for AML prognostic gene expressions.

Methods

We performed a microarray-based analysis for correlations between gene expression and adult AML overall survival (OS) using datasets GSE12417 and GSE8970. Positive findings were validated in an independent cohort of 50 newly diagnosed, non-acute promyelocytic leukemia (APL) AML patients by quantitative RT-PCR and survival analysis.

Results

Microarray-based analysis suggested that expression of eight genes was each associated with 1-year and 3-year AML OS in both GSE12417 and GSE8970 datasets (p?<?0.05). Next, we validated our findings in an independent cohort of AML samples collected in our hospital. We found that ubiquitin-conjugating enzyme E2E1 (UBE2E1) expression was adversely correlated with AML survival (p?=?0.04). Multivariable analysis showed that UBE2E1 high patients had a significant shorter OS and shorter progression-free survival after adjusting other known prognostic factors (p?=?0.03). At last, we found that UBE2E1 expression was negatively correlated with patients’ response to induction chemotherapy (p?<?0.05).

Conclusions

In summary, we demonstrated that UBE2E1 expression was a novel prognostic factor in adult, non-APL AML patients.
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19.

Background

Myocardial performance index (MPI) has been investigated in a variety of populations, but the effect of food intake has not been evaluated. We assessed whether myocardial performance index is affected by food intake in healthy subjects.

Methods

Twenty-three healthy subjects aged 25.6?±?4.5 years were investigated. MPI was measured before, 30 min after, and 110 min after a standardized meal.

Results

MPI decreased significantly (P?<?0.05) from fasting values 30 min after the meal, and had almost returned to baseline after 110 min. MPI decreased from 0.28?±?0.06 (fasting) to 0.20?±?0.07 30 min after eating. At 110 min after eating the index value was almost back to the baseline value 0.26?±?0.06. (P?=?0.15).

Conclusions

This study shows that myocardial performance index is affected by food intake in healthy subjects.
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20.

Objective

To improve the production of welan gum and obtain a carotenoid-free strain while reducing the fermentation and post-treatment costs.

Results

The vitreoscilla globin (vgb) gene combined with the β-galactosidase (lacZ) promoter was inserted into the phytoene synthase (crtB) gene region of the chromosome in Alcaligenes sp. ATCC31555. When the recombinant strain was grown in a 5 l fermentor, welan gum was produced at 24 ± 0.4 g l?1 compared to 21 g ± 0.4 g l?1 in the wild type. Furthermore, the carotenoid-free welan gum produced using Alcaligenes sp. ATCC31555 VHb strain was less expensive with improved properties.

Conclusions

Alcaligenes sp. ATCC31555 VHb strain was a better neutral welan-producing strain with a higher production than the wild-type strain.
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