Aspergillus fumigatus and aspergillosis: From basics to clinics

The airborne fungus Aspergillus fumigatus poses a serious health threat to humans by causing numerous invasive infections and a notable mortality in humans, especially in immunocompromised patients. Mould-active azoles are the frontline therapeutics employed to treat aspergillosis. The global emergence of azole-resistant A. fumigatus isolates in clinic and environment, however, notoriously limits the therapeutic options of mould-active antifungals and potentially can be attributed to a mortality rate reaching up to 100 %. Although specific mutations in CYP 51A are the main cause of azole resistance, there is a new wave of azole-resistant isolates with wild-type CYP 51A genotype challenging the efficacy of the current diagnostic tools. Therefore, applications of whole-genome sequencing are increasingly gaining popularity to overcome such challenges. Prominent echinocandin tolerance, as well as liver and kidney toxicity posed by amphotericin B, necessitate a continuous quest for novel antifungal drugs to combat emerging azole-resistant A. fumigatus isolates. Animal models and the tools used for genetic engineering require further refinement to facilitate a better understanding about the resistance mechanisms, virulence, and immune reactions orchestrated against A. fumigatus. This review paper comprehensively discusses the current clinical challenges caused by A. fumigatus and provides insights on how to address them.

[miR-483-5p aggravates cisplatin-induced premature ovarian insufficiency in rats by targeting FKBP4]

OBJECTIVE

To investigate the role of FKBP4 protein in cisplatin-induced premature ovarian insufficiency (POI).

OBJECTIVE

We performed ITRAQ assay of the ovarian tissues from 4 mice with cisplatin-induced POI and 4 control mice, and identified FKBP4 as a significantly down-regulated protein in the oocytes and granulosa cells following cisplatin treatment. TargetScan software was used for target analysis of FKBP4, and qRT-PCR and Western blotting were used to verify the expression levels of miR-483-5p and FKBP4 in the mouse models. Serum samples were collected from patients with POI and healthy women for detecting miR-483-5p level with qRT-PCR. Cell transfection and dual-luciferase assay were performed to determine the relationship between miR-483-5p and FKBP4. In primary granulosa cells and KGN cells, we examined the effect of miR-483-5p alone, miR-483-5p and cisplatin, and miR-483-5p combined with both cisplatin and FKBP4 on cell apoptosis. We also assessed ovarian function in a transgenic mouse model with ovarian miR-483-5p overexpression in comparison wigh wildtype mice using immunofluorescence assay, in situ hybridization and ELISA.

OBJECTIVE

Ovarian FKBP4 expression was significantly decreased in mice with cisplatin-induced POI. Analysis using TargetScan software indicated that FKBP4 was the potential target of miR-483-5p, which was highly expressed in the ovaries and serum of POI mice and in the serum of patients with POI. In vitro experiments further confirmed that FKBP4 was the target of miR-483-5p. In KGN and primary granulosa cells, FKBP4 overexpression significantly reduced cell apoptosis induced by both cisplatin and miR-483-5p overexpression (P= 0.0045 and 0.0177, respectively). In the transgenic mice with miR-483-5p overexpression in the oocytes, cisplatin induced more severe ovarian damages as compared with those in the wild-type mice.

OBJECTIVE

miR-483-5p/FKBP4 is a new and important pathway in cisplatin-induced POI, in which cisplatin increases ovarian miR- 483-5p expression to result in targeted downregulation of FKBP4. Up-regulation of miR-483-5p may increase ovarian sensitivity to cisplatin and cause severe ovarian dysfunction. Detection of serum miR-483-5p level may help to predict the occurrence and development of POI.

MiR-320c prevents the malignant development of cervical cancer by regulating GABRP level

OBJECTIVE

This study aims to explore the role of microRNA-320c (miR-320c) in regulating biological behaviors of cervical cancer and the potential mechanism, thus providing experimental references for developing therapeutic target of cervical cancer.

PATIENTS AND METHODS

Differential expressions of miR-320c in cervical cancer samples and normal cervical tissues were determined. Potential association between miR-320c level and clinical characteristics of cervical cancer patients was analyzed. After overexpression of miR-320c, migratory potential changes in HeLa, and C33-A cells were examined. At last, target gene binding to miR-320c was predicted online and its involvement in the malignant development of cervical cancer was finally explored.

RESULTS

It was found that miR-320c was lowly expressed in cervical cancer tissues. Compared with cervical cancer patients with high expression of miR-320c, those with low expression had higher rates of lymphatic metastasis and distant metastasis. Besides, the overexpression of miR-320c markedly inhibited migratory potential in HeLa and C33-A cells. GABRP was verified to be the target gene binding to miR-320c. Notably, GABRP was able to reverse the role of miR-320c in regulating migratory potential in cervical cancer.

CONCLUSIONS

MiR-320c is capable of inhibiting migratory potential in cervical cancer by targeting GABRP, which may be utilized as a therapeutic target of cervical cancer.

MiR-808 inhibits cardiomyocyte apoptosis and expressions of caspase-3 and caspase-9 in rats with myocardial infarction by regulating TGF-β1 signaling pathway

OBJECTIVE

To investigate the effects of micro ribonucleic acid (miR)-808 on cardiomyocyte apoptosis and expressions of caspase-3 and caspase-9 in rats with myocardial infarction (MI) by regulating the transforming growth factor-β1 (TGF-β1) signaling pathway.

MATERIALS AND METHODS

A total of 24 specific pathogen-free female Sprague-Dawley rats were enrolled and randomly divided into normal group, model group, and miR-808 group, 8 rats in each group. In the model group and miR-808 group, MI model was prepared by ligation of the left anterior descending coronary artery in the rats. The miR-808 group was transfected with miR-808 lentivirus after the model was established. After one week of intervention, the expression of TGF-β1 was detected by reverse transcription-polymerase chain reaction (RT-PCR). The cardiac function of rats was determined by echocardiography. The myocardium of rats was observed by Masson staining. The cardiomyocyte apoptosis of rats was examined by TdT-mediated dUTP-biotin nick end labeling (TUNEL) method. The expression levels of caspase-3 and caspase-9 were detected by Western blotting.

RESULTS

The expression of TGF-β1 mRNA was higher in the model group than that in the normal group (p<0.05), but compared with that in the model group, it was lower in the miR-808 group. The myocardial function and cardiomyocyte survival rate in the miR-808 group was better and higher than those in the model group (p<0.05). The expression levels of caspase-3 and caspase-9 in the miR-808 group were lower than those in the model group (p<0.05).

CONCLUSIONS

MiR-808 can inhibit cardiomyocyte apoptosis in rats with MI by down-regulating TGF-β1 expression and inhibiting the expressions of caspase-3 and caspase-9.

Longitudinal change in bone mineral density among Chinese individuals with HIV after initiation of antiretroviral therapy

This is the first study to report changes in BMD and related risk factors among Chinese patients with HIV after initiation of tenofovir disoproxil fumarate (TDF)-containing antiretroviral therapy. Greater bone mineral density (BMD) loss was observed in patients treated with TDF, compared to those on non-TDF-containing regimens. Our findings provide important knowledge regarding the risk factors in the long-term clinical management of patients with HIV in China.

INTRODUCTION

Persons living with HIV (PLWH) are at increased risk for osteoporosis and fracture. Tenofovir disoproxil fumarate (TDF) has been associated with higher rates of bone mineral density (BMD) loss, osteoporosis, and fracture. Few studies have studied the impact among PLWH in Asia.

METHODS

We analyzed retrospectively patients from the outpatient HIV clinic of a large tertiary hospital in Beijing, China, from March 2007 to May 2016. Patients who had dual-energy X-ray absorptiometry testing prior to antiretroviral initiation and at 48 and/or 96 weeks after initiation were included in this analysis.

RESULTS

A total of 136 patients were included (mean age 36.0 ± 10.6 years) and over 90% participants were male and Han Chinese ethnicity. We observed greater declines in BMD at the spine from baseline to week 48 (-2.94% vs. -0.74%) and at the hip from baseline to week 96 (-4.37% vs. -2.34%) in the TDF group compared with the non-TDF group. With regard to HIV-specific parameters, longer duration since HIV diagnosis and undetectable viral load over time were associated with lower BMD at the hip [relative risk (RR) 0.97, 95% confidence index (CI) (0.95, 0.99) per 1 year increase and RR 0.96, 95%CI (0.94, 0.99), respectively] and femoral neck [RR 0.97, 95%CI (0.95, 0.99) per 1 year increase and RR 0.97, 95%CI (0.95, 0.998), respectively] over 96 weeks.

CONCLUSIONS

This is the first study to report changes in BMD among PLWH after initiation of TDF-based antiretroviral therapy in China. Our findings provide important knowledge for the long-term clinical management of PLWH from this region.

Improved survival and survival without bronchopulmonary dysplasia in very low birth weight infants after active perinatal care

Background

Perinatal and neonatal care for very low birth weight (VLBW) infants have changed significantly during the past two decades. However, it is unclear how these changes have affected neonatal mortality and morbidity in developing countries.

Objectives

The aim of this study was to investigate the impact of the advanced neonatal care on short-term outcomes of VLBW infants.

Methods

A retrospective study was performed to compare the mortality and morbidity of VLBW infants between period I (2007-2011) and period II (2012-2016) in our unit.

Results

A total of 188 infants in period I and 214 infants in period II were evaluated. The overall in-hospital mortality for VLBW infants dropped from 26.1% in period I to 13.1% in period II. The incidence of birth asphyxia decreased significantly during period II (10.1% [period I] vs 3.7% [period II]). The rate of nasal continuous positive airway pressure (NCPAP) use (69.8% vs 87.1%) and the duration of NCPAP therapy (median: 3 days [period I] vs 5 days [period II]) increased significantly, while the proportion of infants treated with mechanical ventilation and the duration of mechanical ventilation significantly decreased. There was a significant increase in the proportion of survivors without major neonatal morbidity, mainly due to a significant increase in the incidence of survival without bronchopulmonary dysplasia (BPD) (72.7% vs 82.8%). In contrast, the incidence of late-onset sepsis increased significantly during period II (7.9% vs 19.4%).

Conclusions

Active perinatal care is associated with improvements in survival and survival free of BPD for VLBW infants. However, late-onset sepsis is still a major concern.

IL-6 knockout ameliorates myocardial remodeling after myocardial infarction by regulating activation of M2 macrophages and fibroblast cells

OBJECTIVE

To investigate the effects of interleukin-6 (IL-6) gene knockout on myocardial remodeling after myocardial infarction (MI) in mice and the potential mechanism, to provide certain references for the prevention and treatment of MI in clinic.

MATERIALS AND METHODS

A total of 40 male C57 mice were divided into two groups, namely Sham group (n=20) and MI group (n=20), using a random number table. Another 20 mice with IL-6 gene knockout were enrolled into the MI + IL-6 KO group. The MI model was established by means of ligating the left anterior descending coronary artery of the mice. 28 d later, the survival status of the three groups of mice was recorded. In addition, the cardiac functions of each group of mice, including two-dimensional echocardiography, ejection fraction (EF%) and fractional shortening (FS%), were measured. The cross-sectional area and pathological change of the myocardial cells in cardiac tissues of each group of mice were detected via hematoxylin and eosin (H&E) staining. Immunohistochemistry was applied to determine the expression of tumor necrosis factor-alpha (TNF-α) in each group of mouse cardiac tissues. Moreover, immunofluorescent staining was utilized to measure the content of M2 macrophages in each group of mouse cardiac tissues.

RESULTS

The 28-d survival rate of the mice with IL-6 gene knockout was remarkably higher than that of the wild-type mice (p<0.05). Furthermore, the cardiac functions of the mice in the MI + IL-6 KO group were superior to those in the MI group, with markedly improved FS% and EF% (p<0.05). According to the H&E staining results, the cross-sectional areas of the heart and myocardial cells were decreased notably in MI + IL-6 KO group compared with those in the MI group (p<0.05). The immunohistochemical staining results showed that IL-6 knockout could lower the MI-induced high expression of TNF-α (p<0.05), and Masson's trichrome staining indicated that IL-6 knockout could also repress the degree of cardiac fibrosis. Moreover, it was discovered through immunofluorescent staining that the mice in the MI + IL-6 KO group had markedly elevated content of M2 macrophages in cardiac tissues than those in the MI group (p<0.05).

CONCLUSIONS

Inhibiting IL-6 gene expression can prominently ameliorate the MI-induced myocardial remodeling, whose mechanism is possibly associated with the activation of M2 macrophages and reduced collagen production in fibroblast cells.

Downregulated miRNA-26a-5p induces the apoptosis of endothelial cells in coronary heart disease by inhibiting PI3K/AKT pathway

OBJECTIVE

Multiple microRNAs (miRNAs) are abnormally expressed in endothelial cells during the occurrence of coronary artery disease (CAD). Previous researches have demonstrated that miRNA-26a-5p participates in regulating the proliferation of vascular smooth muscle cells and angiogenesis. The aim of this study was to clarify the role of miRNA-26a-5p in regulating cellular performances of endothelial cells in the progression of CAD.

PATIENTS AND METHODS

In vivo CAD model was successfully established by feeding high-fat diet in 8-week-old female ApoE/LDLR-/- mice. CAD mice were administered with miRNA-26a-5p NC or miRNA-26a-5p inhibitor, respectively. Meanwhile, coronary endothelial cells were isolated from CAD mice and normal controls. Relative levels of miRNA-26a-5p, the gene of phosphate and tension homology deleted on chromosome ten (PTEN) and vascular endothelial growth factor (VEGF) in CAD patients and coronary endothelial cells isolated from CAD mice were examined. The regulatory effect of miRNA-26a-5p on atherosclerosis-related genes in primary endothelial cells and HUVECs were detected as well. Moreover, the viability and apoptosis of primary endothelial cells with miRNA-26a-5p knockdown were assessed by cell counting kit-8 (CCK-8) assay and flow cytometry, respectively. Dual-luciferase reporter gene assay was conducted to identify the relationship between miRNA-26a-5p and PTEN. Furthermore, the regulatory role of miRNA-26a-5p in phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway was examined in endothelial cells.

RESULTS

MiRNA-26a-5p and VEGF were significantly downregulated in CAD patients and primary endothelial cells isolated from CAD mice. However, PTEN was significantly upregulated. CAD mice administrated with miRNA-26a-5p inhibitor exhibited remarkably upregulated ET-1, TxA2, and ANG II, as well as downregulated eNOS and PGI2. Conversely, transfection of miRNA-26a-5p mimics in HUVECs obtained the opposite trends. PTEN was identified as the direct target gene of miRNA-26a-5p. Moreover, significantly reduced viability and enhanced apoptotic rate were observed in endothelial cells isolated from CAD mice administrated with miRNA-26a-5p inhibitor. In addition, the protein level of p-AKT in endothelial cells with miRNA-26a-5p knockdown was significantly down-regulated.

CONCLUSIONS

MiRNA-26a-5p influences the proliferative and apoptotic abilities of endothelial cells isolated from CAD mice by targeting PTEN to activate PI3K/AKT pathway.

MiR-1294 acts as a tumor suppressor in clear cell renal cell carcinoma through targeting HOXA6

OBJECTIVE

Renal cancer represents about 3% of all human cancers. Clear cell renal cell carcinoma (ccRCC) is the main type of renal cancer. MicroRNAs (miRNAs) have been reported to play crucial roles in the carcinogenesis of human cancers. This study was aimed to investigate the expression of miR-1294 and the mechanisms underlying miR-1294-mediated ccRCC progression.

MATERIALS AND METHODS

The miR-1294 expression levels in ccRCC cell lines were analyzed by quantified real time-PCR (qRT-PCR). The effect of the miR-1294 expression on the overall survival of ccRCC patients was analyzed by the Kaplan-Meier Plotter. Cell proliferation, colony growth, and cell invasion were examined by cell counting kit-8 assay, colony formation assay, and transwell invasion assay, respectively. The luciferase activity reporter assay and Western blot assay were conducted to validate the connection between miR-1294 and homeobox A6 (HOXA6).

RESULTS

MiR-1294 was downregulated in ccRCC cell lines and correlated with the poor overall survival of ccRCC patients. The overexpression of miR-1294 inhibits ccRCC cell proliferation, colony growth, and cell invasion. HOXA6 was validated as a target of miR-1294 and negatively regulated by miR-1294. The overexpression of HOXA6 attenuated the miR-1294-mediated effects on ccRCC cellular functions.

CONCLUSIONS

Our results indicated that miR-1294 functions as a tumor suppressor in ccRCC. MiR-1294 suppressed cell proliferation, colony formation, and invasion in ccRCC partially via targeting HOXA6.

Policy infrastructure and mechanism to Promote “Health by All” Movement for Overturning Obesity

Background

Obesity is a pressing pandemic. However, major policies have targeted individual responsibility and focused on “losing weight or lowering calories”. Such approach has limited effect and overlooks the hidden obesity.

Methods

Under auspices of NHRI Forum, Taiwan; the WAKE.TAIWAN Research Team analyzed the global trends of policies, strategies, and literatures to formulate guiding principles for a total solution. 1. Defining obesity should go beyond body weight and emphasize more on healthy body composition and muscle mass, etc. 2. Effective obesity control strategy should facilitate building healthy living environments, lifestyle, and culture for natural flow of healthy behaviors. 3. All sectorial leaders should be involved in engaging and promoting healthy lifestyle culture and environment.

Results

”Guidelines for Establishing a lifestyle and Culture of Healthy Body Build” has been published as a blueprint for policy reform and strategies development, which consists of three parts. Part I emphasizes the active roles, social responsibilities, influence, and opportunities confronted the leaders and experts in all sectors and how government may facilitate these societal engagements, “Healthy by All”. The crucial sectors should include academia, NGO/NPO, industry/business, workplaces, healthcare systems, educational sectors, media and press, etc. Part II details on community spatial planning and architectural designs for healthy lifestyles. Part III proposes governmental “Health in All” infrastructure and mechanism.

Conclusions

We anticipate that the Guideline may draw out expertise and volunteering in all sectors of the society and help guide the public to take initiative in building such a culture of healthy-body-build and achieving this goal in all aspects of daily life.

Key messages

Emphasize on healthy body composition rather than body weight. Propagate 'Health by all' movement to foster building 'healthy physique' culture.

LINC00665/miR-9-5p/ATF1 is a novel axis involved in the progression of colorectal cancer

Long noncoding RNAs (lncRNAs) are abnormally expressed in many malignant tumors and involved in regulating the malignant phenotypes of cancer cells. However, the role of LINC00665 in colorectal cancer (CRC) and its regulatory mechanism remain unclear. In this study, real-time polymerase chain reaction (RT-PCR) was used to detect the expressions of LINC00665, miR-9-5p and activating transcription factor 1 (ATF1) mRNA in CRC tissues. The expression of ATF1 in CRC tissues was also detected by immunohistochemistry and Western blot. CCK-8 and colony formation assays were employed to detect cell proliferation. Cell cycle and apoptosis were detected by flow cytometry analysis. Scratch healing assay and Transwell test were exploited to detect cell migration and invasion. The targeting relationships between LINC00665 and miR-9-5p, and miR-9-5p and ATF1 were validated by dual luciferase reporter assay. We found that LINC00665 was significantly overexpressed in CRC tissues, and it was also negatively correlated with the expression of miR-9-5p and positively associated with the expression of ATF1. Besides, LINC00665 promoted the proliferation, migration and invasion of CRC cells, and inhibited cell apoptosis by sponging miR-9-5p. ATF1 was proved to be the downstream target of miR-9-5p and was indirectly regulated by LINC00665. Collectively, it is concluded that LINC00665 contributes to the progression of CRC by regulating miR-9-5p/ATF1 axis.

Unraveling the Topological Phase of ZrTe_{5} via Magnetoinfrared Spectroscopy

For materials near the phase boundary between weak and strong topological insulators (TIs), their band topology depends on the band alignment, with the inverted (normal) band corresponding to the strong (weak) TI phase. Here, taking the anisotropic transition-metal pentatelluride ZrTe_{5} as an example, we show that the band inversion manifests itself as a second extremum (band gap) in the layer stacking direction, which can be probed experimentally via magnetoinfrared spectroscopy. Specifically, we find that the band anisotropy of ZrTe_{5} features a slow dispersion in the layer stacking direction, along with an additional set of optical transitions from a band gap next to the Brillouin zone center. Our work identifies ZrTe_{5} as a strong TI at liquid helium temperature and provides a new perspective in determining band inversion in layered topological materials.

The association of bisphenol A exposure with premature ovarian insufficiency: a case-control study

BACKGROUND

A few epidemiological investigations and animal studies have demonstrated that bisphenol A (BPA) may affect female reproductive health. However, no epidemiologic study has investigated the relationship between BPA exposure and the risk of premature ovarian insufficiency (POI).

METHODS

In this case-control study, urinary concentrations of BPA and serum levels of reproductive hormone were measured. Associations between BPA concentrations and the risk of POI and POI-related hormone levels were estimated.

RESULTS

Among BPA quartiles, no obvious association was found between BPA levels and the risk of POI (p = 0.603). Although the adjusted odds ratio (OR) of POI was slightly increased for participants in the highest BPA concentration quartile, the association was not statistically significant (OR = 1.282, 95% confidence interval [CI] 0.615-2.049 for the highest vs. lowest quartile, p = 0.508). Although follicle stimulating hormone (FSH) and anti-Mullerian hormone (AMH) levels showed no tendency of an association with BPA (p = 0.941 and p = 0.876 for FSH and AMH, respectively), the highest quartile of luteinizing hormone was significantly positively associated with BPA levels (OR = 1.333, 95% CI 0.986-1.803, p = 0.042).

CONCLUSIONS

The urinary concentrations of BPA determined in this study were consistent with the range of exposure currently observed in Chinese women. However, BPA exposure at a relatively low level is not associated with POI in Chinese women. Further epidemiological studies are needed to confirm our findings.

Activation of the STAT1 Pathway Accelerates Periodontitis in Nos3-/- Mice

Early studies on the etiology and pathogenesis of hypertension have shown that it has a considerable association with inflammation and the immune response as well as periodontitis. Clinical studies have also shown that hypertension can promote the periodontal tissue destruction caused by periodontitis. However, the underlying mechanisms remain unclear. This study aimed to explore the possible mechanisms of how hypertension aggravates periodontitis. Treatment with or without the signal transducer and activator of transcription 1 (STAT1) inhibitor fludarabine was performed in an endothelial nitric oxide synthase gene knockout-related (Nos3^-/-) mouse model with the hypertension phenotype of periodontitis induced by bacteria. Micro-computed tomography, immunohistochemistry, Western blot, quantitative reverse transcription polymerase chain reaction, immunofluorescence, and ELISA were performed. We demonstrated that Nos3^-/--related hypertension increases bone resorption and periodontal destruction in periodontitis lesion areas, which can be inhibited by the STAT1 inhibitor. Experimental data also showed that Nos3^-/- significantly increased macrophage infiltration and proinflammatory cytokine expression in the periodontitis lesion area, which is dependent on the angiotensin II-induced STAT1 pathway. Inhibition of STAT1 in vivo can decrease the expression of proinflammatory cytokines and macrophage infiltration. Furthermore, data in this study showed that Nos3^-/--related hypertension further downregulated the STAT3 anti-inflammatory function and its downstream chemokine expression in a STAT1-dependent manner. By applying RAW 264.7 and L929 cell lines and monocytes isolated from Nos3^-/- mice, we confirmed that activation of the STAT1 pathway inhibits STAT3 and its downstream pathway and promotes inflammatory cytokine expression in vitro. Collectively, our current study demonstrated that STAT1 plays an indispensable role in the Nos3^-/--related hypertension with aggravation of periodontitis, suggesting that STAT1 may be a key target for the treatment of periodontitis with hypertension.

Enhanced stability of quantum Hall skyrmions under radio-frequency radiations

We present in this paper the results from a recent study on the stability of the quantum Hall skyrmions state at a Landau level filling factor (ν) close to ν = 1 in a narrow GaAs quantum well. Consistent with previous work, a resonant behavior is observed in the resistively detected NMR measurements. In the subsequent current-voltage (I-V) measurements to examine its breakdown behavior under radio frequency radiations, we observe that the critical current assumes the largest value right at the ⁷⁵As nuclear resonant frequency. We discuss possible origin for this unexpectedly enhanced stability.

Particle-Hole Symmetry and the Fractional Quantum Hall Effect in the Lowest Landau Level

We report on detailed experimental studies of a high-quality heterojunction insulated-gate field-effect transistor (HIGFET) to probe the particle-hole symmetry of the fractional quantum Hall effect (FQHE) states about half-filling in the lowest Landau level. The HIGFET is specially designed to vary the density of a two-dimensional electronic system under constant magnetic fields. We find in our constant magnetic field, variable density measurements that the sequence of FQHE states at filling factors ν=1/3,2/5,3/7… and its particle-hole conjugate states at filling factors 1-ν=2/3,3/5,4/7… have a very similar energy gap. Moreover, a reflection symmetry can be established in the magnetoconductivities between the ν and 1-ν states about half-filling. Our results demonstrate that the FQHE states in the lowest Landau level are manifestly particle-hole symmetric.

First-principles calculations of oxygen octahedral distortions in LaAlO3/SrTiO3(001) superlattices

The size, shape and connectivity of oxide octahedra are essential for understanding and controlling the emergent functional properties of ABO₃ perovskites. Using first-principles calculations, we systematically studied the oxygen octahedral rotation and deformation in LaAlO₃/SrTiO₃(001) superlattices. Superlattices with electron- or hole-doped interfaces, or both, are compared. The results showed that there are at least three different types of oxygen octahedral distortions in these superlattices, which is more than what had previously been reported in the literature. We demonstrate that interfacial oxygen octahedral coupling and hole-doping, in addition to epitaxial strain, are the key factors underlying the formation of multiple types of oxygen octahedral rotations in these systems. We confirm that oxygen octahedral rotations and deformations play an essential role in insulator-metal transitions. Furthermore, octahedral distortion leads to ferroelectricity like dipole formation with the polarization vector always pointing to the positively charged interfaces.

Gut microbiota differences during metamorphosis in sick and healthy giant spiny frogs (Paa spinosa) tadpoles

Gut microbiota plays important roles in host nutrition, immunity, development and health; therefore, disruption of the gut microbiota is closely associated with development of diseases in the host. In amphibians, metamorphosis is associated not only with extensive changes in the gut microbiota, but also with high mortality. Therefore, we hypothesized that unsuccessful restructuring of the gut microbiota during metamorphosis was an important factor that caused the fatalities. To test this hypothesis, we investigated the gut microbiota of apparently sick and healthy giant spiny frog tadpoles during metamorphosis, using high-throughput sequencing of the 16S rRNA gene. Our results showed that most dominant phyla differed significantly among developmental stages of sick and healthy Paa spinosa tadpoles. The differences in the dominant genera in sick and healthy tadpoles were the highest at the stage of degeneration of cloacal tube (TDCT). After the metamorphosis, the composition of the gut microbiota was more alike between healthy and sick tadpoles at the stage of forelimb emergence than at TDCT. These results imply that failed restructuring of the gut microbiota during metamorphosis caused the death of P. spinosa tadpoles. These results provided an important reference to prevent the high actual of P. spinosa tadpoles during metamorphosis. SIGNIFICANCE AND IMPACT OF THE STUDY: We investigated the gut microbiota of apparently sick and healthy giant spiny frog (Paa spinosa) tadpoles during metamorphosis, using high-throughput sequencing of the 16S rRNA gene. Our results showed that the differences in the dominant genera in sick and healthy tadpoles were the highest at the stage of degeneration of cloacal tube. After the metamorphosis, the composition of the gut microbiota was alike between healthy and sick tadpoles. These results imply that failed restructuring of the gut microbiota during metamorphosis caused the death of P. spinosa tadpoles.

[One-stage posterior correction and second-stage anterior debridement and fusion in treating children with thoracic tuberculosis complicated with kyphoscoliosis]

Objective: To investigate the clinical outcomes of one-stage posterior correction surgery and second-stage anterior debridement and fusion in treating children with thoracic tuberculosis complicated with kyphoscoliosis. Methods: From January 2008 to December 2014, a total of 17 children with thoracic vertebral tuberculosis complicated with kyphoscoliosis who underwent a one-stage posterior correction and second-stage anterior debridement and complementary fusion were included. There were 8 males and 9 females with an average age of (8±4) years (5-14 years). All patients underwent posterior correction and anterior debridement and bone graft fusion surgery. The neurological function was determined by Frankel grade. The operation time, estimated blood loss (EBL), levels fused and numbers of screws were recorded. The following radiographic parameters were measured: Cobb angle of the coronal curve, regional kyphosis and sagittal vertical axis (SVA). The incidence of intraoperative and postoperative complications was recorded. The data before and after the operation were compared with paired sample t test. Results: The tuberculosis lesions located in the thoracic vertebrae, and the abscess involved 2 to 4 vertebral segments. The average operation time was (4.1±0.8) h, the EBL was (526±275) ml, the levels fused were 7.6±2.3, and 173 pedicle screws were placed. The preoperative coronal curve averaged 12.6°±6.2°, and it was corrected to 4.2°±1.9° postoperatively (t=4.628, P<0.01), the regional kyphosis was 67.2°±19.4°, and it was corrected to 15.7°±8.2° postoperatively (t=8.192, P<0.01). The SVA improved from (8.1±5.0) mm to (3.0±1.7) mm postoperatively. The mean duration of follow-up for all the patients were (38±11) months. At final follow-up, SVA was reduced to (2.4±2.0) mm and the other parameter kept stable. Thirteen patients had more than one grade improvement of Frankel grade. The VAS score for all patients improved from 4.7±2.8 to 2.2±0.5 postoperatively (t=3.973, P=0.01), and improved to 0.5±0.5 at final follow-up (t=-7.880, P<0.01). No recurrence of primary spinal tuberculosis was seen at final follow-up of all patients. Conclusions: One-stage posterior correction and second-stage anterior complementary debridement and fusion is an effective procedure for children with thoracic tuberculosis complicated with kyphoscoliosis. Significant postoperative deformity correction could be achieved with satisfactory improvement of neurological function. Solid fusion and satisfactory correction maintenance were observed at mid-to long-term follow-up.

P916The effect of a novel, user-friendly, transcatheter edge-to-edge mitral valve repair device in a porcine model of mitral regurgitation

Objective

A new technique has been devised to treat mitral regurgitation (MR) through the transapical route by replicating the edge-to-edge repair surgery. This system encompasses an easy-to-use leaflet clamp and a smaller-sized delivery system (14F–16F). We aimed to evaluate the effectiveness of this device in a porcine model of acute MR.

Methods

Acute MR was induced in 36 anesthetized porcine subjects by severing the major chordae supporting the corresponding segment of the leaflet. This device was then transapically implanted on the prolapsing segment under 3D epicardial echocardiographic guidance. All of the animals were killed 30 days after the procedure to verify the proper location of the implanted devices.

Results

Cutting the major chordae induced an eccentric MR jet (MR grade: 3+, 27.8%/4+, 72.2%) in all of the animals. Every single pig was then successfully implanted with one clamp. The duration of catheterization ranged from 18 to 40 minutes. Overt MR reduction was observed following the procedure through echocardiography; residual MR was mild in 8 cases, trivial in 19 cases, and absent in 9 cases. In terms of hemodynamic parameters, the mean and maximum mitral valve pressure gradients were increased significantly (p<0.01), but these values were less than 4 mmHg in all of the cases. Autopsy demonstrated that all but one device were precisely placed to clip the prolapsing segment of the mitral valve, and there was no evidence of thrombosis, thromboembolism or impairment of the cardiac structure.

Table 1. Changes in hemodynamic parameters, cardiac size, and functional parameters after the procedure Preoperation Postoperation P value MR-maxA (mm2) 7.27±2.13 1.54±1.29 0.000 MVPG-max (mmHg) 1.95±0.47 3.66±0.62 0.000 MVPG-mean (mmHg) 0.87±0.31 1.7±0.28 0.000 LVEDD (mm) 46.08±2.85 46.44±3.53 0.239 LVESD (mm) 29.11±3.44 29.08±3.62 0.940 LVEF (%) 66.53±6.4 67.14±4.93 0.256 LAD (mm) 35.75±2.24 36.42±1.99 0.057 LAA (mm2) 12.95±2.22 12.64±1.55 0.301

Figure 1

Conclusions

Transapical implantation of the novel mitral valve repair device is effective and safe in reducing acutely induced MR in pigs; thus, suggesting that it has great potential for clinical benefit in patients with MR.

Acknowledgement/Funding

Shanghai Science and Technology Committee

Abstract 3161: Novel evidence for Trefoil Factor 3 as an oncogenic mediator of disease progression, and a potential predictor for neoadjuvant chemotherapy in colorectal cancer

Colorectal cancer (CRC) is a major cause of morbidity and mortality throughout the world. The increased incidence rates of CRC places a considerable burden on individuals and society in Asian countries. Although surgical resection remains the standard treatment for CRC patients, accumulating evidences showed advanced patients derived an additional benefit from molecular targeted agents. Therefore, there is a great need to identify novel cellular targets in CRC that can be exploited for therapeutic benefit. Trefoil factor 3 (TFF3), is a member of a family of small secretory proteins characterized by three intrachain disulfide bonds constituting the trefoil motif. TFF3 was initially found as a mediator of mucosal healing and play a critical role in epithelial restitution. Recent studies showed that TFF3 may contribute to tumorigenesis. However, its role in CRC remains unclear. Herein, the protein expression of TFF3 was measured in colorectal adenoma polyps (PLP, n=20), cancer tissues (n=20) and matched adjacent healthy tissues (n=20) by immunohistochemical (IHC) assay. We further evaluated serum and urine level of TFF3 from healthy volunteers (n=40), PLP patients (n=40) and CRC patients (n=40) by using ELISA assay. To investigate the functional or mechanistic role of TFF3 in CRC, we conducted several in vivo and in vitro approaches. The IHC showed that TFF3 was frequently overexpressed in cancer tissues (12/20, P&lt;0.0001), while scarcely detected in PLP (2/20) or healthy tissues (3/20). In addition, serum or urine level of TFF3 was increased in CRC patients, compared to PLP patients or healthy volunteers (P=0.00032). Intriguingly, we found patients with lower serum TFF3 level are more sensitive to neoadjuvant chemotherapy than those with higher TFF3 level (with 3.4 fold increase, P&lt;0.0001). With regard to biological function of TFF3, we found overexpression of TFF3 in CRC cell lines HCT-116 and SW480 significantly enhanced cell viability, invasion, and colony formation capacity. Subsequent mice model validated its oncogenic role in CRC, which TFF3 treatment remarkably enhances xenograft growth. In conjunction with its higher serum level in chemoresistant patients, we found overexpression of TFF3 endows HCT-116 cells with 5’-Fluorouracil resistant phenotype. Mechanistically, we observed overexpression of TFF3 is sufficient to activate Akt and Autophagy pathways in HCT-116 and SW480 cells, confirming its correlation with malignant clinical and biological phenotype. In conclusion, we identified TFF3 as a novel diagnostic marker in CRC and a promising predictor for neoadjuvant chemotherapy. Targeting TFF3 may provide an effective strategy for improving treatment of this malignancy.

Note: This abstract was not presented at the meeting.

Citation Format: Ying Long, Tsuyoshi Ozawa, Hanhua Li, Weijie Pan, Wenhao Weng. Novel evidence for Trefoil Factor 3 as an oncogenic mediator of disease progression, and a potential predictor for neoadjuvant chemotherapy in colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3161.