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1.
Biomater Sci ; 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31965126

RESUMO

Six cationic lipidoid fluorodendrimers are synthesized to construct hybrid lipid-polymer nanoparticles for siRNA delivery. By screening the nanoplatforms including fluorodendrimers with different chemical structures, the optimized nanoparticle NPF13-5 mediates the most efficient silencing of prohibitin 1, inhibition of cell proliferation, and induction of cell apoptosis towards A549 lung adenocarcinoma cells.

2.
Drug Deliv ; 27(1): 180-190, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31924103

RESUMO

In this work, a pH-sensitive liposome-polymer nanoparticle (NP) composed of lipid, hyaluronic acid (HA) and poly(ß-amino ester) (PBAE) was prepared using layer-by-layer (LbL) method for doxorubicin (DOX) targeted delivery and controlled release to enhance the cancer treatment efficacy. The NP with pH-sensitivity and targeting effect was successfully prepared by validation of charge reversal and increase of hydrodynamic diameter after each deposition of functional layer. We further showed the DOX-loaded NP had higher drug loading capacity, suitable particle size, spherical morphology, good uniformity, and high serum stability for drug delivery. We confirmed that the drug release profile was triggered by low pH with sustained release manner in vitro. Confocal microscopy research demonstrated that the NP was able to effectively target and deliver DOX into human non-small cell lung carcinoma (A549) cells in comparison to free DOX. Moreover, the blank NP showed negligible cytotoxicity, and the DOX-loaded NP could efficiently induce the apoptosis of A549 cells as well as free DOX. Notably, in vivo experiment results showed that the DOX-loaded NPs effectively inhibited the growth of tumor, enhanced the survival of tumor-bearing mice and improved the therapeutic efficacy with reduced side-effect comparing with free drug. Therefore, the NP could be a potential intelligent anticancer drug delivery carrier for cancer chemotherapy, and the LbL method might be a useful strategy to prepare multi-functional platform for drug delivery.

3.
J Cell Commun Signal ; 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31925646

RESUMO

Esophageal squamous cell carcinoma (ESCC) is one of the most common malignant tumors with poor prognosis. Aryl hydrocarbon receptor (AHR) is a ligand-dependent transcription factor and emerging evidence shows it is associated with tumor initiation and promotion. However, the relationship between AHR and ESCC is not clear and it is meaningful to explore whether AHR could be a therapeutic target. In the present study, immunohistochemistry was performed to determine AHR expression levels in ESCC tissues. Knockdown of AHR expression in ESCC cell lines genetically and modulation of AHR by 3, 3'-diindolylmethane (DIM) pharmacologically both in vitro and in vivo were utilized to examine the corresponding alterations in cell growth, migration and invasion. Our study indicated that AHR expression levels were elevated in ESCC and associated with poor prognosis. Both knockdown and modulation of AHR inhibited tumor progression through down-regulating expression levels of PCNA, Bcl-2, Cyclin D1, MMP1, MMP2, MMP9 and up-regulating expression levels of Bax, Cleaved-Caspase 3. Our findings also indicated that repressing COX2/PGE2/STAT3 axis exerted inhibitory effects on ESCC both in vitro and in vivo assays. Taken together, AHR plays the key role in ESCC progression and targeting AHR as a therapeutic strategy with DIM is deserved for further exploration.

4.
Sci Total Environ ; 707: 136130, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-31869608

RESUMO

BACKGROUND: The general population is widely exposed to fenvalerate. However, the effects of maternal exposure to fenvalerate on neurodevelopment in offspring and the underlying metabolic mechanism are largely unknown. METHODS: Pregnant mice were exposed to fenvalerate for 11 consecutive days. The forced swimming test (FST) was performed in 35 day-old offspring to investigate the effects of fenvalerate on neurobehavioral responses. Blood serum free T4 and free T3 concentrations were measured using commercial ELISA. Blood and thyroid samples were used for metabolomic analyses with UPLC Q-Exactive. The expression levels of neurotransmitter metaolite receptors were determined in the frontal cortex of offspring using real-time PCR. RESULTS: The immobility time, free T4 and free T3, and expression levels of Htr1a and Htr2a were statistically changed in offspring male mice. Metabolomic analysis revealed that the pentose phosphate pathway, starch and sucrose metabolism, glutamic acid metabolism were the key changed pathways in the blood, and thiamine metabolism was the key changed pathway in the thyroid. CONCLUSION: Prenatal exposure to fenvalerate affected neurodevelopment in male offspring mice both via the changed abundances of metabolites involved in glycolysis related metabolism and medium-chain fatty acid metabolism, and the changes in 5-HT receptor expression.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31788470

RESUMO

Neural stem cells, which are confined in localised niches are unable to repair large brain lesions because of an inability to migrate long distances and engraft. To overcome these problems, previous research has demonstrated the use of biomaterial implants to redirect increased numbers of endogenous neural stem cell populations. However, the fate of the diverted neural stem cells and their progeny remains unknown. Here we show that neural stem cells originating from the subventricular zone can migrate to the cortex with the aid of a long-lasting injectable hydrogel within a mouse brain. Specifically, large numbers of neuroblasts were diverted to the cortex through a self-assembling ß-peptide hydrogel that acted as a tract from the subventricular zone to the cortex of transgenic mice (NestinCreERT2:R26eYFP) in which neuroblasts and their progeny are permanently fluorescently labelled. Moreover, neuroblasts differentiated into neurons and astrocytes 35 days post implantation, and the neuroblast-derived neurons were Syn1 positive suggesting integration into existing neural circuitry. In addition, astrocytes co-localised with neuroblasts along the hydrogel tract, suggesting that they assisted migration and simulated pathways similar to the native rostral migratory stream. Lower levels of astrocytes were found at the boundary of hydrogels with encapsulated brain-derived neurotrophic factor, comparing with hydrogel implants alone.

6.
Ann Transl Med ; 7(20): 544, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31807526

RESUMO

Background: To investigate the influence of preoperative physical training combining aerobic and breathing exercises on surgical lung cancer patients with impaired lung function. Methods: A total of 68 patients with predicted postoperative FEV1% <60% were equally and randomly assigned into one-week physical training combining aerobic and breathing exercises (intervened group: IG) or routine preoperative preparation (control group: CG). Then, 6-min walking distance (6-MWD), in-hospital length of stay (LOS), and other clinical variables were included and recorded. Results: An increase of 22.6±27.0 m of 6-MWD was observed in IG, compared to 2.7±27.6 m in CG (between-group difference: 19.9 m, 95% CI: 6.7 to 33.2, P=0.004), but no difference was found in lung function. The emotional function of EORTC-QLQ-30 was significantly improved in IG after the training regimen, compared to CG. Meanwhile, the intervened patients (IG) had significantly lower postoperative pulmonary complication (PPC) rate (11.8%, 4/34 vs. 35.3%, 12/34, P=0.022), shorter postoperative LOS [median: 5.0 interquartile (4.0-7.0) vs. 8.0 (7.0-10.0) days, P<0.001] and lower costs, including total cost [48,588.7 (44,999.1-52,693.3) vs. 52,445.3 (49,002.9-61,994.0) ¥, P=0.016], material cost [23,350.8 (18,300.6-26,421.9) vs. 25,730.0 (21,328.7-29,250.2) ¥, P=0.048] and drug cost [7,230.0 (6,661.9-8,347.4) vs. 11,388.6 (7,963.0-16,314.3) ¥, P<0.001]. Conclusions: The preoperative physical training combining aerobic and breathing exercises can improve exercise capacity, decrease the occurrence of PPCs, and shorten LOS with lower in-hospital cost; it thus shows potential to be an effective preparation strategy for surgical lung cancer patients with limited lung function.

7.
Phys Chem Chem Phys ; 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31829378

RESUMO

Fe-Based bulk metallic glasses (BMGs) with a composition of Fe48Cr15Mo14C15B6Y2 have recently been reported with good application performance due to their excellent mechanical and chemical properties, showing excellent corrosion resistance, remarkable forming and processing ability, ultrahigh yield strength and large elasticity. Here, we report on a new functional application for such Fe-based BMGs, which can exhibit better catalytic performance than the pristine Fe surface. The hydrogen evolution and dissociation processes of one and two H2O molecules on both BMG and pristine Fe surfaces are investigated using first-principles calculations. The energy barriers of the dissociation processes on the BMG surface are lower than those on the pristine Fe surface. Moreover, the structural configurations along the dissociation path during hydrogen evolution show that it is easier for H2O molecules to dissociate into H2 on the surface of the BMG, rendering it a more active catalyst than the pristine Fe surface. Analyses on the electronic structures show further evidence that the BMG surface has a stronger ability to facilitate charge transfer at the interface and is more inclined to accept transferred charges, thereby promoting its catalytic activity. These findings shed light on understanding the functional applications of BMGs and are anticipated to be highly meaningful for further experimental investigations.

8.
BMC Ophthalmol ; 19(1): 256, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31842802

RESUMO

BACKGROUND: Accurate measurement and reconstruction of orbital soft tissue is important to diagnosis and treatment of orbital diseases. This study applied an interactive graph cut method to orbital soft tissue precise segmentation and calculation in computerized tomography (CT) images, and to estimate its application in orbital reconstruction. METHODS: The interactive graph cut method was introduced to segment extraocular muscle and intraorbital fat in CT images. Intra- and inter-observer variability of tissue volume measured by graph cut segmentation was validated. Accuracy and reliability of the method was accessed by comparing with manual delineation and commercial medical image software. Intraorbital structure of 10 patients after enucleation surgery was reconstructed based on graph cut segmentation and soft tissue volume were compared within two different surgical techniques. RESULTS: Both muscle and fat tissue segmentation results of graph cut method showed good consistency with ground truth in phantom data. There were no significant differences in muscle calculations between observers or segmental methods (p > 0.05). Graph cut results of fat tissue had coincidental variable trend with ground truth which could identify 0.1cm3 variation. The mean performance time of graph cut segmentation was significantly shorter than manual delineation and commercial software (p < 0.001). Jaccard similarity and Dice coefficient of graph cut method were 0.767 ± 0.045 and 0.836 ± 0.032 for human normal extraocular muscle segmentation. The measurements of fat tissue were significantly better in graph cut than those in commercial software (p < 0.05). Orbital soft tissue volume was decreased in post-enucleation orbit than that in normal orbit (p < 0.05). CONCLUSION: The graph cut method was validated to have good accuracy, reliability and efficiency in orbit soft tissue segmentation. It could discern minor volume changes of soft tissue. The interactive segmenting technique would be a valuable tool for dynamic analysis and prediction of therapeutic effect and orbital reconstruction.

10.
Nano Lett ; 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31874042

RESUMO

The science of protein self-assembly has experienced significant development, from discrete building blocks of self-assembled nanoarchitectures to advanced nanostructures with adaptive functionalities. Despite the prominent achievements in the field, the desire of designing de novo protein-nanoparticle (NP) complexes and constructing dynamic NP systems remains highly challenging. In previous works, l-rhamnulose-1-phosphate aldolase (C98RhuA) tetramers were self-assembled into two-dimensional (2D) lattices via disulfide bond interactions. These interactions provided 2D lattices with high structural quality and a sophisticated assembly mode. In this study, we devised a rational design for RhuA building blocks to fabricate 2D functionalized protein lattices. More importantly, the lattices were used to direct the precise assembly of NPs into highly ordered and diverse nanoarchitectures. These structures can be employed as an excellent tool to adequately verify the self-assembly mode and structural quality of the designed RhuA crystals. The subsequent redesign of RhuA building blocks enabled us to predictably produce a novel protein lattice whose conformational dynamics can be controllably regulated. Thus, a dynamic system of AuNP lattices was achieved. Transmission electron microscopy and small-angle X-ray scattering indicated the presence of these diverse NP lattices. This contribution enables the fabrication of future NP structures in a more programmable manner with more expected properties for potential applications in nanoelectronics and other fields.

11.
Clin Chim Acta ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31758934

RESUMO

BACKGROUND: The polycystic ovary syndrome (PCOS) is the most common endocrine and metabolic disorder syndrome of women in reproductive age. Metabolomic studies of the follicular fluid can reveal the potential metabolic pathways related to PCOS. The objection of this study was to explore the changes of metabolites in the follicular fluid of PCOS. METHODS: We collected follicular fluid samples of 35 patients with PCOS and 33 controls without PCOS for metabolomic analysis with UPLC Q-Exactive. The identified metabolites were annotated with KEGG and HMDB to determine the disturbances of metabolic pathways in PCOS. Based on the regression model, we conducted the ROC analysis to find the biomarker of PCOS in the follicular fluid. RESULTS: Metabolomic analysis identified 21 differential metabolites in PCOS, which revealed that the Vitamin B6 metabolism, phenylalanine metabolism and carnitine synthesis were the key changed pathways. We found that 7ß-Hydroxycholesterol was potential biomarker of PCOS based on the ROC analysis. CONCLUSION: We identified metabolic alterations and biomarker in the follicular fluid of PCOS, providing novel ways for the diagnosis and treatment of PCOS.

12.
Metabolites ; 9(11)2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31684074

RESUMO

:Pre-clinical safety evaluation of traditional medicines is imperative because of the universality of drug-induced adverse reactions. Psoralen and isopsoralen are the major active molecules and quality-control components of a traditional herbal medicine which is popularly used in Asia, Fructus Psoraleae. The purpose of this study is to assess the long-term effects of psoralen and isopsoralen with low levels on the biochemical parameters and metabolic profiles of rats. Three doses (14, 28, and 56 mg/kg) of psoralen and one dose (28 mg/kg) of isopsoralen were administered to rats over 12 weeks. Blood and selected tissue samples were collected and analyzed for hematology, serum biochemistry, and histopathology. Metabolic changes in serum samples were detected via proton nuclear magnetic resonance (1H-NMR) spectroscopy. We found that psoralen significantly changed the visceral coefficients, blood biochemical parameters, and histopathology, and isopsoralen extra influenced the hematological index. Moreover, psoralen induced remarkable elevations of forvaline, isoleucine, isobutyrate, alanine, acetone, pyruvate, glutamine, citrate, unsaturated lipids, choline, creatine, phenylalanine, and 4-hydroxybenzoate, and significant reductions of ethanol and dimethyl sulfone. Isopsoralen only induced a few remarkable changes of metabolites. These results suggest that chronic exposure to low-level of psoralen causes a disturbance in alanine metabolism, glutamate metabolism, urea cycle, glucose-alanine cycle, ammonia recycling, glycine, and serine metabolism pathways. Psoralen and isopsoralen showed different toxicity characteristics to the rats.

13.
Cancer Manag Res ; 11: 8181-8190, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31564977

RESUMO

Objectives: To examine the predictive role of Glasgow Prognostic Score (GPS) on long-term survival in esophageal cancer. Method: Comprehensive searches of electronic databases were performed to identify potential studies that evaluated the prognostic value of pretreatment GPS in esophageal cancer patients. We combined the hazard ratios (HRs) with 95% confidence intervals (CIs) to assess the association of GPS with overall survival (OS), disease-free survival (DFS) and cancer-specific survival (CSS). Results: A total of 21 studies including 6115 patients were analyzed. Compared with patients with GPS 0, patients with elevated GPS had poorer OS (HR =2.12, 95% CI: 1.83-2.45, P<0.001) and CSS (HR =2.16, 95% CI: 1.56-2.98, P<0.001); but no significant relationship was observed between the elevated GPS and DFS (HR=2.14, 95% CI:1.00-4.61, P=0.051). Subgroup analysis outcomes were similar to overall analyses. Conclusion: Pretreatment GPS could serve as a valuable factor in predicting the prognosis of patients with esophageal cancer. More well-designed prospective studies are warranted to confirm our findings.

14.
ACS Appl Mater Interfaces ; 11(43): 40564-40574, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31566943

RESUMO

The fabrication of metal-organic framework (MOF)-based macro-materials is considered as a promising strategy toward the practical applications of powdered MOF crystals. In this study, selective laser sintering (SLS), an advanced three-dimensional (3D) powder printing technique, has been employed to fabricate MOF-polymer mixed matrix films (MMFs) by using thermoplastic polyamide 12 (PA12) powder as the matrix material and five types of MOFs including ZIF-67, NH2-MIL-101(Al), MOF-801, HKUST-1, and ZIF-8 crystals as the fillers. A three-layer HKUST-1-PA12 complex with a grid pattern is fabricated to demonstrate the printability of 3D MOF-polymer structure. Single-layer MMFs with grid patterns are printed by using the five types of MOF fillers with different mass loadings to study their free-standing characteristic, thickness, specific surface area, hydrophilia, water permeate flux, and mechanical stability. The methylene blue (MB) adsorption tests are conducted using the NH2-MIL-101(Al)-PA12 MMFs with different grid patterns to exemplify the applications of the MMFs for water purification. It is confirmed that the MOF components retain their high maximum adsorption capacity, and the printed MMFs can be conveniently regenerated for cyclic utilization. This work provides an insight into the utilization of advanced 3D printing technology to manufacture macro-MOF-polymer materials for practical applications.

15.
Pathol Res Pract ; 215(11): 152637, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31570278

RESUMO

Gastric cancer (GC) represents one of the most predominant malignancies with high incidence and mortality rates. Although traditional chemotherapeutics, including cisplatin are effective in the treatment of GC, patients often develop drug resistance in clinic. The present study aimed to explore the underlying mechanism of cisplatin-induced drug resistance in GC. The potential role of DNA demethylase ten-eleven translocation-2 (TET2) in modulating cisplatin resistance of GC cells was investigated. It was observed that TET2 was significantly decreased in cisplatin resistance SGC7901/DDP cells compared with non-resistant cells and TET2 overexpression markedly reduced the tolerance to cisplatin. Additionally, evidence was provided that TET2 regulated interleukin-6 levels in the tumor microenvironment through histone acetylation and therefore served an important role in the development of cisplatin resistance in GC cells. Taken together, the results suggested that TET2-mediated cisplatin resistance may represent a novel mechanism of drug resistance in GC cells and may offer novel treatment approaches.

16.
Surg Endosc ; 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31586253

RESUMO

BACKGROUND: Emergency endoscopic retrograde cholangiopancreatography (ERCP) for ascending acute cholangitis in patients with severe comorbidities is challenging. Here, we evaluated the efficacy and safety of one-stage ERCP in such patients by performing a retrospective study. METHODS: We included all patients with ascending acute cholangitis and undergoing ERCP between January 2017 and March 2019. In total, we recruited 212 patients: 74 and 138 with and without severe comorbidities, respectively. We collected and analyzed data related to basal characteristics, ERCP, and clinical outcomes. RESULTS: Elderly age (76.20 ± 9.99 years vs. 66.52 ± 8.16 years, P = 0.000), higher levels of leukocyte count (15.86 ± 2.47 × 109/ml vs. 13.49 ± 1.65 × 109/ml, P = 0.000), and serum bilirubin (3.11 ± 1.29 mg/dl vs. 1.94 ± 0.90 mg/dl, P = 0.000) were present in patients with severe comorbidities. A significantly higher proportion of these patients were severe cases (32.4% vs. 6.5%, P = 0.000), American Society of Anesthesiologists (ASA) stage V status (37.8% vs. 10.1%, P = 0.000) and had undergone general anesthesia (56.8% vs. 18.8%, P = 0.000). Successful biliary cannulation and complete stone clearance in one session were achieved in 207 and 202 patients, respectively. Mean length of hospital stay was 8.02 ± 2.71 days. Forty-three patients required ICU stay with the mean length of 3.26 ± 3.51 days. In-hospital mortality occurred in seven patients; all these patients had severe comorbidities. ERCP details, including urgent and early ERCP, biliary cannulation, complete stone clearance in one session, stent insertion, and complications were not significantly different between the two groups. Patients with severe comorbidities had a longer in-hospital stay (9.39 ± 3.15 days vs. 7.29 ± 2.11 days, P = 0.000), a higher proportion of ICU admission (45.9% vs. 6.5%, P = 0.000), and a longer ICU stay length (4.88 ± 4.37 days vs. 1.44 ± 0.52 days, P = 0.000). Our data also revealed that early diagnosis is an important predictor associated with clinical outcomes. CONCLUSIONS: One-stage ERCP is safe and effective for ascending acute cholangitis caused by choledocholithiasis. Early diagnosis is a significant predictor of clinical outcomes.

17.
Int J Nanomedicine ; 14: 8001-8011, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31632014

RESUMO

Background: The development of biocompatible nanocarriers that can efficiently encapsulate and deliver anticancer drug to the tumor site and provide controlled release of cargos in response to the specific cues for cancer therapy is of great significance. Methods: In this work, dual pH/redox-responsive fabrication of hybrid lipid-polymer nanoparticles (LPNPs) self-assembled from amphiphilic polymer poly(ethylene glycol) methyl ether-grafted disulfide-poly(ß-amino esters) (PBAE-ss-mPEG) and PEGylated lipid were prepared and used as drug delivery carriers. The optimization of PEGylated lipid modification was confirmed by analysis of particle size, polydispersity index (PDI), cellular uptake, serum stability, and drug loading capacity. The pK b value of LPNPs was determined as 6.55, indicating the pH-sensitivity. The critical micelle concentration (CMC) values and zeta-potential of LPNPs at different pH values were investigated to confirm its pH-sensitivity. The morphology of LPNPs before and after incubation with reducing agent was imaged to study the redox-responsibility. Results: The in vitro results showed that the drug had controlled release from LPNPs triggered by low pH and high concentration of reducing agent. Furthermore, the cytotoxicity of LPNPs was very low, and the doxorubicin (DOX)-loaded LPNPs could efficiently induce the death of tumor cells in comparison to free DOX. Conclusion: All results demonstrated that the fabricated LPNPs could be potential anticancer drug delivery carriers with a pH/redox-triggered drug release profile, and PEGylated lipid modification might be a useful method to fabricate the drug delivery platform.

18.
Cancer Cell Int ; 19: 264, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31632198

RESUMO

Background: Centromere Protein F (CENPF) associates with the centromere-kinetochore complex and influences cell proliferation and metastasis in several cancers. The role of CENPF in breast cancer (BC) bone metastasis remains unclear. Methods: Using the ONCOMINE database, we compared the expression of CENPF in breast cancer and normal tissues. Findings were confirmed in 60 BC patients through immunohistochemical (IHC) staining. Microarray data from GEO and Kaplan-Meier plots were used analyze the overall survival (OS) and relapse free survival (RFS). Using the GEO databases, we compared the expression of CENPF in primary lesions, lung metastasis lesions and bone metastasis lesions, and validated our findings in BALB/C mouse 4T1 BC models. Based on gene set enrichment analysis (GSEA) and western blot, we predicted the mechanisms by which CENPF regulates BC bone metastasis. Results: The ONCOMINE database and immunohistochemical (IHC) showed higher CENPF expression in BC tissue compared to normal tissue. Kaplan-Meier plots also revealed that high CENPF mRNA expression correlated to poor survival and shorter progression-free survival (RFS). From BALB/C mice 4T1 BC models and the GEO database, CENPF was overexpressed in primary lesions, other target organs, and in bone metastasis. Based on gene set enrichment analysis (GSEA) and western blot, we predicted that CENPF regulates the secretion of parathyroid hormone-related peptide (PTHrP) through its ability to activate PI3K-AKT-mTORC1. Conclusion: CENPF promotes BC bone metastasis by activating PI3K-AKT-mTORC1 signaling and represents a novel therapeutic target for BC treatment.

19.
Appl Environ Microbiol ; 85(22)2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31492669

RESUMO

In deep-sea hydrothermal vent environments, sulfur-oxidizing bacteria belonging to the clade SUP05 are crucial symbionts of invertebrate animals. Marine viruses, as the most abundant biological entities in the ocean, play essential roles in regulating the sulfur metabolism of the SUP05 bacteria. To date, vent sponge-associated SUP05 and their phages have not been well documented. The current study analyzed microbiomes of Haplosclerida sponges from hydrothermal vents in the Okinawa Trough and recovered the dominant SUP05 genome, designated VS-SUP05. Phylogenetic analysis showed that VS-SUP05 was closely related to endosymbiotic SUP05 strains from mussels living in deep-sea hydrothermal vent fields. Homology and metabolic pathway comparisons against free-living and symbiotic SUP05 strains revealed that the VS-SUP05 genome shared many features with the deep-sea mussel symbionts. Supporting a potentially symbiotic lifestyle, the VS-SUP05 genome contained genes involved in the synthesis of essential amino acids and cofactors that are desired by the host. Analysis of sponge-associated viral sequences revealed putative VS-SUP05 phages, all of which were double-stranded viruses belonging to the families Myoviridae, Siphoviridae, Podoviridae, and Microviridae Among the phage sequences, one contig contained metabolic genes (iscR, iscS, and iscU) involved in iron-sulfur cluster formation. Interestingly, genome sequence comparison revealed horizontal transfer of the iscS gene among phages, VS-SUP05, and other symbiotic SUP05 strains, indicating an interaction between marine phages and SUP05 symbionts. Overall, our findings confirm the presence of SUP05 bacteria and their phages in sponges from deep-sea vents and imply a beneficial interaction that allows adaptation of the host sponge to the hydrothermal vent environment.IMPORTANCE Chemosynthetic SUP05 bacteria dominate the microbial communities of deep-sea hydrothermal vents around the world, SUP05 bacteria utilize reduced chemical compounds in vent fluids and commonly form symbioses with invertebrate organisms. This symbiotic relationship could be key to adapting to such unique and extreme environments. Viruses are the most abundant biological entities on the planet and have been identified in hydrothermal vent environments. However, their interactions with the symbiotic microbes of the SUP05 clade, along with their role in the symbiotic system, remain unclear. Here, using metagenomic sequence-based analyses, we determined that bacteriophages may support metabolism in SUP05 bacteria and play a role in the sponge-associated symbiosis system in hydrothermal vent environments.

20.
Bioinformation ; 15(7): 480-489, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31485134

RESUMO

Drought is one of the major abiotic stresses causing yield losses and restricted growing area for several major crops. Rice being a major staple food crop and sensitive to water-deficit conditions bears heavy yield losses due to drought stress. To breed drought tolerant rice cultivars, it is of interest to understand the mechanisms of drought tolerance. In this regard, large amount of publicly available transcriptome datasets could be utilized. In this study, we used different transcriptome datasets obtained under drought stress in comparison to normal conditions (control) to identify novel drought responsive genes and their underlying molecular mechanisms. We found 517 core drought responsive differentially expressed genes (DEGs) and different modules using gene co-expression analysis to specifically predict their biological roles in drought tolerance. Gene ontology and KEGG analyses showed key biological processes and metabolic pathways involved in drought tolerance. Further, network analysis pinpointed important hub DEGs and major transcription factors regulating the expression of drought responsive genes in each module. These identified novel DEGs and transcription factors could be functionally characterized using systems biology approaches, which can significantly enhance our knowledge about the molecular mechanisms of drought tolerance in rice.

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