Publications by authors named "Quan Gan"

80 Publications

Macrocyclic Aromatic Amide Foldamer: Synthesis, Twisted-to-Boxlike Conformational Switching, and Molecular Recognition.

Chempluschem 2021 Jun 8;86(6):920-923. Epub 2021 Jun 8.

Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China.

In this study, a twisted macrocycle was synthesized via ring closure of a double-helical aromatic oligoamide foldamer with two disulfide bridges. Single-crystal X-ray structure and NMR spectroscopy demonstrate the twisted conformation of macrocycle both in the solid state and in solution. As a result of the rearrangement of hydrogen bonding preference, the twisted conformation could be transformed to boxlike through protonation of the pyridine segments of macrocycle. In addition, the NMR titration experiments revealed that flat aromatic guests (e. g., coronene and perylene) could bind to the boxlike macrocycle with a 1 : 1 binding stoichiometry. The addition of base to the host-guest complexes resulted in conformational reversal of the macrocycle from boxlike to twisted as well as the release of guest.
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http://dx.doi.org/10.1002/cplu.202100193DOI Listing
June 2021

A Disulfide Switch Providing Absolute Handedness Control in Double Helices via Conversion from the Antiparallel to Parallel Helical Pattern.

Chemistry 2021 May 20. Epub 2021 May 20.

Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China.

A strategy to reversibly switch the parallel/antiparallel helical conformation of aromatic double helices through the formation/breakage of a disulfide bond is presented. Single-crystal X-ray structures, NMR, and circular dichroism spectroscopy demonstrate that the double helices with terminal thiol groups favor an antiparallel helical arrangement both in the solid state and in solution, while the P/M bias of helicity induced by chiral segments from another extremity of the sequence is weak in this structural motif. The antiparallel helices can be rearranged to parallel helices through the disulfide connection of the sequences. This change enhances the bias of helical handedness and results in absolute chirality control of the double helices. The handedness-mediated process can be governed by the oxidation-reduction cycle, thereby switching the structural arrangement and the enhancement of chiral bias. In addition, we find that the sequences can dimerize into an intermolecular double helix with the disulfide connection. And the helical handedness is also fully controlled due to the head-to-head structural motif.
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http://dx.doi.org/10.1002/chem.202101221DOI Listing
May 2021

Hierarchical communication of chirality for aromatic oligoamide sequences.

Nat Commun 2021 05 11;12(1):2659. Epub 2021 May 11.

Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, Hubei Engineering Research Center for Biomaterials and Medical Protective Materials, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, P. R. China.

The communication of chirality at a molecular and supramolecular level is the fundamental feature capable of transmitting and amplifying chirality information. Yet, the limitation of one-step communication mode in many artificial systems has precluded the ability of further processing the chirality information. Here, we report the chirality communication of aromatic oligoamide sequences within the interpenetrated helicate architecture in a hierarchical manner, specifically, the communication is manipulated by three sequential steps: (i) coordination, (ii) concentration, and (iii) ion stimulus. Such approach enables the information to be implemented progressively and reversibly to different levels. Furthermore, the chiral information on the side chains can be accumulated and transferred to the helical backbones of the sequences, resulting in that one of ten possible diastereoisomers of the interpenetrated helicate is finally selected. The circular dichroism experiments with a mixture of chiral and achiral ligands demonstrate a cooperative behavior of these communications, leading to amplification of chiral information.
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http://dx.doi.org/10.1038/s41467-021-22984-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8113567PMC
May 2021

microRNA-181a promotes the proliferation of hypertrophic scar fibroblasts and inhibits their apoptosis via targeting phosphatase and tensin homolog.

Ann Palliat Med 2021 Apr;10(4):4563-4571

Department of Burn Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.

Background: This study aimed to compare the expression of microRNA (miR)-181a and phosphatase and tensin homolog (PTEN) in hypertrophic scar tissue and cells and to explore the effects of miR-181a and PTEN on the proliferation and apoptosis of the human scar fibroblast cell line HSFb.

Methods: HSFb cells were transfected with miR-negative control (miR-NC), miR-181a mimics, miR-181a inhibitor, pcDNA3.1-PTEN (pc-PTEN), or small interfence-PTEN (si-PTEN) plasmid using a Lipofectamine 2000 transfection kit. The effects of miR-181a and PTEN on the proliferation and apoptosis of HSFb were determined using a Cell Counting Kit (CCK)-8 experiment and flow cytometry, respectively. The effects of miR-181a and PTEN on the expression of apoptosis-related proteins in HSFb, including type I collagen (Col-1) and type III collagen (Col-3), were measured by western blot. Finally, the relationship between miR-181a and PTEN was explored by the dual-luciferase reporter gene experiment.

Results: The miR-181a in hypertrophic scar tissues and HSFb were significantly up-regulated compared to embryo skin fibroblast (ESF-1) cells and normal tissues (P<0.05), whereas the opposite results were seen for PTEN expression (P<0.05). Inhibiting miR-181a or upregulating the expression of PTEN significantly suppressed the proliferation of HSFb (P<0.05) and induced their apoptosis (P<0.05). Western blot revealed that inhibiting and upregulating miR-181a and PTEN, respectively, decreased the expression of the B-cell lymphoma-2 (Bcl-2), Col-1, and Col-3 proteins in HSFb, but significantly up-regulated the expression of Bcl-2-associated X protein (Bax), cleaved caspase-3 (c-caspase-3), and cleaved caspase-9 (c-caspase-9) (P<0.05). The dual-luciferase reporter gene experiment results confirmed PTEN to be the downstream target gene of miR-181a. Simultaneous upregulation of miR-181a and PTEN expression had no significant effect on the proliferation and apoptosis of HSFb.

Conclusions: miR-181a promotes the up-regulation of Col-1 and Col-3, and regulates the proliferation and apoptosis of HSFb by targeting PTEN, thereby enhancing the formation of hypertrophic scarring (HS). Therefore, miR-181a and PTEN may be potential therapeutic targets for the treatment of HS.
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http://dx.doi.org/10.21037/apm-21-604DOI Listing
April 2021

Quality of life among pregnant women with urinary incontinence: A cross-sectional study in a Malaysian primary care clinic.

PLoS One 2021 28;16(4):e0250714. Epub 2021 Apr 28.

Klinik Kesihatan Kajang, Jalan Semenyih, Kajang, Selangor, Malaysia.

Background: Pregnant women have an increased risk of urinary incontinence (UI), affecting their quality of life (QoL). This study aims to determine UI and its relationship with QoL among incontinent pregnant women.

Methods: This was a cross-sectional study in a semi-urban primary care clinic in Selangor, Malaysia, among pregnant women aged 18 years old and above. The validated study instruments consisted of questions on socio-demography, the International Consultation on Incontinence Questionnaire-UI Short Form (ICIQ-UI SF) to determine UI and the International Consultation on Incontinence Questionnaire Lower Urinary Tract Symptoms Quality of Life Module (ICIQ-LUTSQoL) to assess their QoL. A generalised linear model was used to determine the association between the continent and incontinent pregnant women with QoL.

Results: Of the approached 610 respondents, 440 consented to participate in the study, resulting in a response rate of 72.1%. The mean age was 29.8 years old (SD 4.69) with 82.2% (n = 148) having stress UI. Significant independent factors related to the decreased QoL were mid to late trimester (OR 3.06, 95% CI 1.48-6.32), stress UI, (OR 6.94, 95%CI 4.00-12.04) and urge UI (OR3.87, 95%CI 0.48-31.28). Non-Malay improved QoL (OR 0.29, 95% CI 0.16-0.52).

Conclusions: All types of UI significantly affecting pregnant women's QoL. This information is useful in enhancing antenatal management at the primary care level, whereby they should be screened for UI and provided with effective early intervention to improve their QoL.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0250714PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8081257PMC
April 2021

Tidal Effects on the Longitudinal Structures of the Martian Thermosphere and Topside Ionosphere Observed by MAVEN.

J Geophys Res Space Phys 2020 Dec 1;126(2). Epub 2021 Feb 1.

Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, USA.

Longitudinal structures in the Martian thermosphere and topside ionosphere between 150 and 200 km altitudes are studied using in situ electron and neutral measurements from the NASA Mars Atmosphere and Volatile EvolutioN (MAVEN) mission. Four time intervals are selected for comparison, during which MAVEN sampled similar local time (9.3-10.3 h) and latitude (near 20°S) regions but at different solar longitude positions (two near northern summer solstice, one each at northern vernal and autumnal equinoxes). Persistent and pronounced tidal oscillations characterize the ionosphere and thermosphere, whose longitudinal variations in density are generally in-phase with each other. Our analysis of simultaneous and collocated neutral and electron data provides direct observational evidence for thermosphere-ionosphere coupling through atmospheric tides. We conclude that the ionosphere is subject to modulation by upward-propagating thermal tides, via both tide-induced vertical displacement and photochemical reactions. Atmospheric tides constitute a ubiquitous and significant perturbation source to the ionospheric electron density, up to ~15% near 200 km.
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http://dx.doi.org/10.1029/2020ja028562DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8011558PMC
December 2020

Studies on the Regulatory Roles and Related Mechanisms of lncRNAs in the Nervous System.

Oxid Med Cell Longev 2021 13;2021:6657944. Epub 2021 Mar 13.

The Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen, Guangdong, China.

Long noncoding RNAs (lncRNAs) have attracted extensive attention due to their regulatory role in various cellular processes. Emerging studies have indicated that lncRNAs are expressed to varying degrees after the growth and development of the nervous system as well as injury and degeneration, thus affecting various physiological processes of the nervous system. In this review, we have compiled various reported lncRNAs related to the growth and development of central and peripheral nerves and pathophysiology (including advanced nerve centers, spinal cord, and peripheral nervous system) and explained how these lncRNAs play regulatory roles through their interactions with target-coding genes. We believe that a full understanding of the regulatory function of lncRNAs in the nervous system will contribute to understand the molecular mechanism of changes after nerve injury and will contribute to discover new diagnostic markers and therapeutic targets for nerve injury diseases.
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http://dx.doi.org/10.1155/2021/6657944DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7984887PMC
May 2021

Selective CO Electrochemical Reduction Enabled by a Tricomponent Copolymer Modifier on a Copper Surface.

J Am Chem Soc 2021 02 11;143(7):2857-2865. Epub 2021 Feb 11.

Joint Center for Artificial Photosynthesis and The Arnold and Mabel Beckman Laboratory of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States.

Electrochemical CO reduction over Cu could provide value-added multicarbon hydrocarbons and alcohols. Despite recent breakthroughs, it remains a significant challenge to design a catalytic system with high product selectivity. Here we demonstrate that a high selectivity of ethylene (55%) and C products (77%) could be achieved by a highly modular tricomponent copolymer modified Cu electrode, rivaling the best performance using other modified polycrystalline Cu foil catalysts. Such a copolymer can be conveniently prepared by a ring-opening metathesis polymerization, thereby offering a new degree of freedom for tuning the selectivity. Control experiments indicate all three components are essential for the selectivity enhancement. A surface characterization showed that the incorporation of a phenylpyridinium component increased the film robustness against delamination. It was also shown that its superior performance is not due to a morphology change of the Cu underneath. Molecular dynamics (MD) simulations indicate that a combination of increased local CO concentration, increased porosity for gas diffusion, and the local electric field effect together contribute to the increased ethylene and C product selectivity.
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http://dx.doi.org/10.1021/jacs.0c12478DOI Listing
February 2021

LncRNA MIR205HG regulates melanomagenesis via the miR-299-3p/VEGFA axis.

Aging (Albany NY) 2021 02 1;13(4):5297-5311. Epub 2021 Feb 1.

Xinxiang Central Hospital, Xinxiang 453000, Henan, China.

In this study, we investigated the role of lncRNA MIR205HG in melanomagenesis. Quantitative real-time PCR (qRT-PCR) analysis showed that MIR205HG levels were significantly upregulated in melanoma cell lines compared to normal human melanocytes. Similarly, MIR205HG levels were significantly higher melanoma tissues than adjacent normal skin tissues (n=30). CCK-8 and flow cytometry assays showed that MIR205HG knockdown significantly decreased the viability of melanoma cells. Dual luciferase reporter and RNA pull-down assays confirmed that MIR205HG directly binds to microRNA (miR)-299-3p. Targetscan analysis and dual luciferase reporter assays showed that miR-299-3p directly binds to the 3'UTR of VEGFA mRNA. Wound healing and transwell invasion assays showed that MIR205HG knockdown decreased migration and invasiveness of melanoma cells, and these effects were reversed by treatment with miR-299-3p inhibitor. MIR205HG-silenced melanoma cells showed increased miR-299-3p expression and lower levels of both VEGFA mRNA and protein. Tumor volumes were significantly smaller in nude mice xenografted with MIR205HG knockdown melanoma cells than the controls. These results demonstrate that MIR205HG supports melanoma growth via the miR-299-3p/VEGFA axis. This makes MIR205HG a potential therapeutic target for the treatment of melanoma.
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http://dx.doi.org/10.18632/aging.202450DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7950277PMC
February 2021

Circular RNA circSEC24A Promotes Cutaneous Squamous Cell Carcinoma Progression by Regulating miR-1193/MAP3K9 Axis.

Onco Targets Ther 2021 22;14:653-666. Epub 2021 Jan 22.

Department of Dermatological, Xinxiang Central Hospital, Xinxiang City, Henan Province, People's Republic of China.

Background: Circular RNAs (circRNAs) have been increasingly demonstrated to play critical roles in cancer progression. However, the biological functions and underlying mechanism of circRNA SEC24 homolog A, COPII coat complex component (circSEC24A) in cutaneous squamous cell carcinoma (CSCC) have not been well elucidated yet.

Methods: The expression levels of circSEC24A, microRNA-1193 (miR-1193) and mitogen-activated protein kinase kinase kinase 9 (MAP3K9) were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) or Western blot. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and colony formation assay were used to assess cell proliferation ability. Flow cytometry and transwell assay were utilized to detect cell apoptosis and migration and invasion. Glycolytic metabolism was examined via the measurement of lactate production, glucose consumption, extracellular acidification rate (ECAR), hexokinase 2 (HK2) and Lactate dehydrogenase A (LDHA) expression. The interaction between miR-1193 and circSEC24A or MAP3K9 was predicted by starBase v2.0 and verified by dual-luciferase reporter, RNA Immunoprecipitation (RIP) and pull-down assay assays. The mice xenograft model was established to investigate the roles of circSEC24A in vivo.

Results: CircSEC24A and MAP3K9 were upregulated and miR-1193 was downregulated in CSCC tissues and cells. CircSEC24A knockdown inhibited the progression of CSCC cells by inhibiting cell proliferation, migration, invasion, and glycolysis and inducing apoptosis. Moreover, miR-1193 was a direct target of circSEC24A and its downregulation reversed the inhibitory effect of circSEC24A knockdown on the progression of CSCC cells. Furthermore, MAP3K9 was a downstream target of miR-1193 and its upregulation attenuated the anti-cancer role of miR-1193 in CSCC cells. Additionally, circSEC24A acted as a molecular sponge of miR-1193 to regulate MAP3K9 expression. Furthermore, interference of circSEC24A repressed tumor growth via upregulating miR-1193 and downregulating MAP3K9.

Conclusion: CircSEC24A interference suppressed the progression of CSCC by regulating miR-1193/MAP3K9 axis, which might be a promising strategy for CSCC treatment.
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http://dx.doi.org/10.2147/OTT.S275691DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7837553PMC
January 2021

Long non-coding RNA PICSAR knockdown inhibits the progression of cutaneous squamous cell carcinoma by regulating miR-125b/YAP1 axis.

Life Sci 2021 Jun 22;274:118303. Epub 2020 Aug 22.

Department of Dermatology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China. Electronic address:

Aims: The purpose of this study was to explore the precise role and mechanism of p38 inhibiting cutaneous squamous cell carcinoma associated lincRNA (PICSAR) in CSCC.

Materials And Methods: The expression levels of PICSAR, microRNA-125b (miR-125b) and yes-associated protein1 (YAP1) were determined by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation, apoptosis and invasion were evaluated by Cell Counting Kit-8 (CCK-8) assay, flow cytometry, transwell assay, respectively. The interaction between miR-125b and PICSAR or YAP1 was predicted by bioinformatics software and confirmed by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. Western blot was employed to detect the protein expression of YAP1. The mice xenograft model was established to investigate the role of PICSAR in vivo.

Key Findings: PICSAR was upregulated in CSCC tissues and cells. PICSAR knockdown inhibited cell proliferation and invasion and induced apoptosis in CSCC cells. Moreover, miR-125b could directly bind to PICSAR and its inhibition reversed the effect of PICSAR knockdown on proliferation, invasion and apoptosis in CSCC cells. In addition, YAP1 was a direct target of miR-125b and its overexpression attenuated the anti-cancer role of miR-125b in CSCC cells. Furthermore, YAP1 expression was positively regulated by PICSAR and negatively regulated by miR-125b. Besides, interference of PICSAR suppressed tumor growth by upregulating miR-125b and downregulating YAP1.

Significance: PICSAR knockdown suppressed cell proliferation and invasion and promoted apoptosis in CSCC cells by regulating miR-125b/YAP1 axis, providing new sights for treatment of CSCC.
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http://dx.doi.org/10.1016/j.lfs.2020.118303DOI Listing
June 2021

Absolute handedness control of oligoamide double helices by chiral oxazolylaniline induction.

Org Biomol Chem 2020 Sep 21;18(34):6643-6650. Epub 2020 Aug 21.

Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China.

Aromatic oligoamide double helices bearing a chiral oxazolylaniline moiety at the C-terminus were synthesized and their helix handedness was completely controlled (de > 99%). The absolute helix sense and the de values were evaluated by using H NMR, X-ray crystallography, and circular dichroism (CD). Using crystal structure analysis, the high efficiency of helix handedness induction was attributed to the close location of the asymmetric carbon center to the helix orbits via intramolecular hydrogen bonding. The CD experiments also showed that there is no loss of chiral induction either in the interconversion of single and double helices or by elongation of the sequences.
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http://dx.doi.org/10.1039/d0ob01503bDOI Listing
September 2020

Acute fatty liver of pregnancy cases in a maternal and child health hospital of China: Three case reports.

Medicine (Baltimore) 2020 Jul;99(29):e21110

Department of Obstetrics.

Rationale: Acute fatty liver of pregnancy (AFLP) is extremely hazardous to pregnant woman in the 3rd trimester of pregnancy. AFLP has an insidious onset and nonspecific experimental indicators, which therefore is difficult to be diagnosed.

Patient Concerns: Case 1 was transferred to our hospital for hypertensive disorders complicating pregnancy at gestation of 38 weeks + 3 days. Case 2 was transferred to our hospital for suspicious fetal heart monitoring response at gestation of 36 weeks + 4 days. Case 3 was transferred to our hospital for prelabor rupture of membranes at gestation of 37 weeks + 1 days.

Diagnosis: The diagnosis of AFLP was based on the Swansea criteria.

Interventions: All 3 cases were delivered by cesarean section, and they were all transferred to intensive care unit for further treatment. Cases 2 and 3 were subjected to plasma exchange and continuous renal replacement therapy.

Outcomes: In this study, all 3 patients were initially diagnosed as gastritis. In addition, case 1 was diagnosed as preeclampsia and her AFLP was misdiagnosed with postpartum hemorrhage after cesarean delivery. Case 2 was admitted to the hospital for intrahepatic cholestasis of pregnancy and fetal distress, but we considered it as AFLP before delivery. Case 3 was treated according to severe intrahepatic cholestasis of pregnancy, but we rediagnosed it as postpartum hemorrhage and disseminated intravascular coagulation after cesarean delivery. Neonatal asphyxia and complications were not found. All of the 3 cases were fully recovered and discharged from our hospital.

Lessons: If there are multiple risk factors including vomiting, abdominal pain, and fetal distress, AFLP should be highly suspected. Early diagnosis, especially before termination of pregnancy, is the key to successful treatment of AFLP.
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http://dx.doi.org/10.1097/MD.0000000000021110DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7373617PMC
July 2020

Comparison of Microdilution Method with Agar Dilution Method for Antibiotic Susceptibility Test of .

Infect Drug Resist 2020 15;13:1775-1780. Epub 2020 Jun 15.

Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, Nanjing, People's Republic of China.

Introduction: Antimicrobial resistance (AMR) of () becomes a grave public health problem in the world. A strengthened Antimicrobial Resistance Surveillance Program is needed to track the trend of AMR development. However, the lack of a proper antimicrobial susceptibility test (AST) method is a barrier to expand the AMR surveillance in China. Traditional agar dilution (AD) method is laborious and E-test strips have no approval license for clinical use. Herein, a Chinese group modified the microdilution (MD) method for clinical ASTs. The objective of this study is to compare the MD method with the AD method for AST.

Materials And Methods: A total of 166 clinical isolates were tested for antimicrobial susceptibility of ceftriaxone, spectinomycin, azithromycin, ciprofloxacin, tetracycline, and penicillin using MD and AD method simultaneously. Results of MD method were read manually or automatically. Rates of essential agreement (EA), category agreement (CA), minor error, and very major error were compared.

Results: The total EAs (compared with results read manually) of penicillin, tetracycline, ciprofloxacin, spectinomycin, ceftriaxone, and azithromycin were 90.4%, 97.0%, 85.5%, 100.0%, 94%, and 72.3%; and CAs were 82.5%, 94.0%, 100%, 100%, 95.2%, and 94%, respectively.

Conclusion: We conclude that the MD method might be an alternative for clinical AST of in China. In particular, MD method has the potency of accurate differentiation of isolates resistant to ceftriaxone or azithromycin, which were empirically recommended for gonococcal treatment, but its quality remained suboptimal, and further improvement is needed for clinical use.
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http://dx.doi.org/10.2147/IDR.S253811DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7304676PMC
June 2020

Quantitative effects of atmospheric diffusion on surface aerosol extinction in the Pearl River Delta region.

Sci Total Environ 2020 Jul 11;727:138472. Epub 2020 Apr 11.

Foshan Meteorology Bureau, Foshan/Foshan Tornado Research Center, Guangdong, China; Guangdong Ecological Meteorology Center, Guangzhou, Guangdong, China.

Aerosol pollution is closely related to meteorological conditions. In order to accurately evaluate the effectiveness of emission reduction policies, it is very important to separate meteorological effects from emissions in long-term PM changes. In this study, we used surface extinction coefficient (SEC) of aerosol particles as an indicator to estimate the long-term trend of PM pollutant conditions, and proposed a parameter surface ventilation index (SVI) to describe the atmospheric diffusion. A novel method was introduced to quantify the effect of atmospheric diffusion and emissions on SEC from an inter-annual scale, and its applicability and limitations was discussed. The results showed that annual mean SEC exhibited an increasing trend with a rate of 15.6 Mm∙year from 2000 to 2007 and a decreasing trend with a rate of 14.4 Mm∙year from 2008 to 2018. The annual frequency distribution of SVI obeyed a lognormal distribution. The SVI value mainly concentrated between 300 and 3600 ms, SEC was negatively correlated with SVI in this range. In most cases, SEC variations were mainly dominated by emissions, and SEC variations at clean sites were more influenced by atmospheric diffusion than that at polluted sites. Emissions remained high during 2003-2007, then gradually decreased during 2008-2014 and finally accelerated decrease during 2015-2018, indicating that control policies have effectively mitigated PM pollution since 2008. In generally, this method can provide valuable information for policy makers to evaluate the emission control measures for air pollution mitigation and prevention.
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http://dx.doi.org/10.1016/j.scitotenv.2020.138472DOI Listing
July 2020

Sludge-derived biochar with multivalent iron as an efficient Fenton catalyst for degradation of 4-Chlorophenol.

Sci Total Environ 2020 Jul 1;725:138299. Epub 2020 Apr 1.

School of Environmental Science & Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China; Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, 1037 Luoyu Road, Wuhan, Hubei 430074, China; State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China.

Fe-rich biochar with multivalent iron compounds (Fe, FeC, FeO, and FeAlO) pyrolyzed from sludge cake conditioned with Fenton's reagent and red mud was utilized as an efficient Fenton catalyst for the degradation of 4-chlorophenol (4-CP). Effects of pyrolysis temperature and sludge conditioner composition on the transformation of iron compounds were studied. Both homogeneous Fenton reaction initiated by Fe leached from both low-valent Fe and FeC, and heterogeneous Fenton reaction initiated by solid iron phases of FeO and FeAlO were revealed to contribute to the degradation of 4-CP. The removal efficiency of 4-CP remained 100% after five successive degradation rounds. The homogeneous Fenton reaction mainly works in the first degradation round, and the heterogeneous Fenton reaction dominates in subsequent degradation rounds. The findings of this study suggest that sewage sludge derived Fe-rich biochar could be utilized as an efficient Fenton catalyst for recalcitrant organics degradation.
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http://dx.doi.org/10.1016/j.scitotenv.2020.138299DOI Listing
July 2020

3D Cascaded Convolutional Networks for Multi-vertebrae Segmentation.

Curr Med Imaging 2020 ;16(3):231-240

School of Automation, Harbin University of Science and Technology, Harbin 150001, China.

Background: Automatic approach to vertebrae segmentation from computed tomography (CT) images is very important in clinical applications. As the intricate appearance and variable architecture of vertebrae across the population, cognate constructions in close vicinity, pathology, and the interconnection between vertebrae and ribs, it is a challenge to propose a 3D automatic vertebrae CT image segmentation method.

Objective: The purpose of this study was to propose an automatic multi-vertebrae segmentation method for spinal CT images.

Methods: Firstly, CLAHE-Threshold-Expansion was preprocessed to improve image quality and reduce input voxel points. Then, 3D coarse segmentation fully convolutional network and cascaded finely segmentation convolutional neural network were used to complete multi-vertebrae segmentation and classification.

Results: The results of this paper were compared with the other methods on the same datasets. Experimental results demonstrated that the Dice similarity coefficient (DSC) in this paper is 94.84%, higher than the V-net and 3D U-net.

Conclusion: Method of this paper has certain advantages in automatically and accurately segmenting vertebrae regions of CT images. Due to the easy acquisition of spine CT images. It was proven to be more conducive to clinical application of treatment that uses our segmentation model to obtain vertebrae regions, combining with the subsequent 3D reconstruction and printing work.
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http://dx.doi.org/10.2174/1573405615666181204151943DOI Listing
June 2021

Comment on the Influence of Smoking Status on the Health Profiles of Older Chinese American Men.

Authors:
Quan Gan

J Am Geriatr Soc 2020 03 9;68(3):669-670. Epub 2020 Jan 9.

The International Union Against Tuberculosis and Lung Disease, New York, New York.

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http://dx.doi.org/10.1111/jgs.16326DOI Listing
March 2020

Donor-Acceptor-Type Conjugated Polymer-Based Multicolored Drug Carriers with Tunable Aggregation-Induced Emission Behavior for Self-Illuminating Cancer Therapy.

ACS Appl Mater Interfaces 2019 Nov 31;11(45):41853-41861. Epub 2019 Oct 31.

State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X) , Soochow University , 199 Ren'ai Road , Suzhou 215123 , P. R. China.

Nowadays, multicolored drug carriers have exhibited high significance in designing self-illuminating drug delivery systems to adapt different experimental conditions. In this study, we developed an efficient strategy for self-illuminating antitumor therapy using multicolored aggregation-induced emission (AIE)-active drug carriers by tuning electron donor moieties in donor-acceptor (D-A) structures. Three amphipathic conjugated polymers, to , were successfully synthesized using an AIE-active tetraphenylethylene (TPE) moiety and donor-acceptor (D-A)-type electronic structure. Interestingly, the fluorescence behavior of to could be tuned between aggregation-caused quenching and AIE by changing the electron donor moiety. Their fluorescence color in aqueous solution could be easily adjusted from yellow to red by choosing stronger electron donors. After the anticancer drug paclitaxel was loaded, two AIE-active polymers, and , could be engineered into polymer dots (Pdots) and applied in self-illuminating cancer therapy. The Pdots could not only reveal their location by a yellow- or red-colored fluorescence signal but also exhibit almost two times in vivo antitumor efficacy, high biocompatibility, and obvious tumor-targeting behavior compared to the commercially available anticancer drug Taxol. Furthermore, dots exhibited similar in vivo antitumor efficacy and biocompatibility compared to nonemission Abraxane, a commercially available drug delivery system. This work demonstrates the significant application of a D-A-type structure in the design of self-illuminating drug delivery systems.
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http://dx.doi.org/10.1021/acsami.9b11237DOI Listing
November 2019

Quadruple hybridization of quinoline-triazole oligomers.

Chem Commun (Camb) 2019 Sep;55(73):10968-10971

Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China.

A series of quinoline-triazole oligomers and their quadruple helical structures are demonstrated. The helical folding is mainly induced by the intramolecular hydrogen bonds, and solvophobic effects impel the aggregation, causing the quadruplex to be more stable in DMSO than in CDCl3 by four orders of magnitude. As a proof of concept, our studies reveal a tetramerization mechanism in which the single sequences first hybridize to dimers, and then two such dimers further aggregate into a quadruplex.
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http://dx.doi.org/10.1039/c9cc05506aDOI Listing
September 2019

One-pot solvothermal synthesis of magnetic biochar from waste biomass: Formation mechanism and efficient adsorption of Cr(VI) in an aqueous solution.

Sci Total Environ 2019 Dec 12;695:133886. Epub 2019 Aug 12.

School of Environmental Science & Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China; Hubei Provincial Engineering Laboratory of Solid Waste Treatment, Disposal and Recycling, 1037 Luoyu Road, Wuhan, Hubei 430074, China; State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China. Electronic address:

A facile one-pot solvothermal method was applied to synthesize a magnetic biochar composite (MB) using phoenix tree leaves-derived biochar as the carbon matrix. The structure of MB was optimized by varying the load ratio and particle size of FeO nanoparticles on biochar. Time-dependent structure and composition evolution of solid and liquid phases during heterogeneous solvothermal process were investigated to understand the formation mechanism of MB. Firstly, Fe/Fe ions were coordinated by oxygen-containing groups on biochar and part of them were hydrolyzed to form iron hydroxides. Then, those iron-containing precursors were thermally decomposed and reduced to iron oxides; and finally FeO nanoparticles were generated. The MB had an adsorption capacity for Cr(VI) of 55.0 mg/g in an aqueous solution, which exceeds those of biochar (39.8 mg/g) and FeO nanoparticles (26.5 mg/g). The adsorption mechanism study reveals that biochar as a carbon skeleton mainly provided binding sites for Cr(VI) and electron-donor groups for reduction of Cr(VI), while FeO nanoparticles mainly involved in the immobilization of newly formed Cr(III) through formation of Fe(III)-Cr(III) hydroxide. MB exhibited a stable structure with a lower Fe leakage at pH 2.0 than that of a comparable magnetic biochar sample prepared by conventional co-precipitation method. Recycling experiments suggested that MB could keep 84% of its initial removal capability for Cr(VI) even after seven cycles. The results indicate that solvothermal method is a promising alternative to prepare magnetic biochar for adsorption of heavy metal-containing wastewater.
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http://dx.doi.org/10.1016/j.scitotenv.2019.133886DOI Listing
December 2019

CO/CH Competitive Adsorption in Shale: Implications for Enhancement in Gas Production and Reduction in Carbon Emissions.

Environ Sci Technol 2019 Aug 29;53(15):9328-9336. Epub 2019 Jul 29.

Department of Petroleum Geology & Geology, School of Geosciences , University of Aberdeen , AB24 3UE , Aberdeen , U.K.

CO/CH interaction determines the prospects for complementary enhanced gas recovery (EGR) associated with CO sequestration in shale. We characterize the competitive adsorption of CO and CH in shale using low-field NMR. Competitive sorption of CO relative to CH is defined as the CO/CH competitive adsorption ratio (CO/CH CAR for short) when CO and CH have the same original partial pressure in shale. Results indicate the CO/CH CAR decreases with the logarithm of increasing pressure. Observed CO/CH CARs are on the order of 4.28-5.81 (YDN-1) to 3.43-5.57 (YDN-2), describing the remarkable competitive advantage of CO sorption relative to CH for shale. Results also indicate that increasing the CO/CH pressure ratio (1) increases the adsorption capacity of shales to CO and decreases that to CH logarithmically with pressure, and (2) boosts CO-CH displacement and generates greater EGR efficiency in shale, where the EGR efficiency can be inferred by the CO/CH pressure ratio using a Langmuir-like function. Furthermore, the maximum sequestration capacity of adsorbed CO during CO-CH competition is on the order of ∼3.87 cm/g (YDN-1) to ∼5.13 cm/g (YDN-2). These promising results for EGR and CO storage reveal the considerable potential for carbon capture and geological sequestration in shale.
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http://dx.doi.org/10.1021/acs.est.9b02432DOI Listing
August 2019

Deciduous DPSCs Ameliorate MPTP-Mediated Neurotoxicity, Sensorimotor Coordination and Olfactory Function in Parkinsonian Mice.

Int J Mol Sci 2019 Jan 29;20(3). Epub 2019 Jan 29.

Centre of Excellence for Omics-Driven Computational Biodiscovery, AIMST University, Bedong, Kedah 08100, Malaysia.

Parkinson's disease (PD) is a neurodegenerative disorder defined by progressive deterioration of dopaminergic neurons in the substantia nigra pars compacta (SNpc). Dental pulp stem cells (DPSCs) have been proposed to replace the degenerated dopaminergic neurons due to its inherent neurogenic and regenerative potential. However, the effective delivery and homing of DPSCs within the lesioned brain has been one of the many obstacles faced in cell-based therapy of neurodegenerative disorders. We hypothesized that DPSCs, delivered intranasally, could circumvent these challenges. In the present study, we investigated the therapeutic efficacy of intranasally administered DPSCs in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model of PD. Human deciduous DPSCs were cultured, pre-labelled with PKH 26, and intranasally delivered into PD mice following MPTP treatment. Behavioural analyses were performed to measure olfactory function and sensorimotor coordination, while tyrosine hydroxylase (TH) immunofluorescence was used to evaluate MPTP neurotoxicity in SNpc neurons. Upon intranasal delivery, degenerated TH-positive neurons were ameliorated, while deterioration in behavioural performances was significantly enhanced. Thus, the intranasal approach enriched cell delivery to the brain, optimizing its therapeutic potential through its efficacious delivery and protection against dopaminergic neuron degeneration.
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http://dx.doi.org/10.3390/ijms20030568DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6387212PMC
January 2019

Fluorometric Recognition of Nucleotides within a Water-Soluble Tetrahedral Capsule.

Angew Chem Int Ed Engl 2019 03 6;58(13):4200-4204. Epub 2019 Feb 6.

Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK.

The design of aqueous probes and binders for complex, biologically relevant anions presents a key challenge in supramolecular chemistry. Herein, a tetrahedral assembly with cationic faces and corners is reported that is capable of discriminating between anionic and neutral guests in water. Electrostatic repulsion between subcomponents can be overcome by the addition of an anionic template, or generating a robust covalent framework by incorporating tris(2-aminoethyl)amine (TREN). The resultant TREN-capped, water-soluble, fluorescent cage binds mono- and poly-phosphoric esters, including nucleotides. Its covalent skeleton renders it stable at micromolar concentrations in water, enabling the fluorometric detection of biologically relevant guests in an aqueous environment. Selective supramolecular encapsulants, such as 1, could enable new sensing applications, such as recognition of toxins and drugs, under biological conditions.
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http://dx.doi.org/10.1002/anie.201814149DOI Listing
March 2019

Directional Threading and Sliding of a Dissymmetrical Foldamer Helix on Dissymmetrical Axles.

Angew Chem Int Ed Engl 2019 03 20;58(13):4205-4209. Epub 2019 Feb 20.

CBMN (UMR5248), Univ. Bordeaux-CNRS-IPB, Institut Européen de Chimie et Biologie, 2 rue Escarpit, 33600, Pessac, France.

We have investigated the self-assembly of a dissymmetrical aromatic oligoamide helix on linear amido-carbamate rods. A dissymmetric sequence bearing two differentiated ends is able to wrap around dissymmetric dumbbell guest molecules. Structural and thermodynamic investigations allowed us to decipher the mode of binding of the helix that can bind specifically to the amide and carbamate groups of the rod. In parallel kinetic studies of threading and sliding of the helix along linear axles were also monitored by H NMR. Results show that threading of a dissymmetrical host can be kinetically biased by the nature of the guest terminus allowing a preferential sense of sliding of the helix. The study presented below further demonstrates the valuable potential of foldaxanes to combine designed molecular recognition patterns with fine control of self-assembly kinetics to conceive complex supramolecular events.
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http://dx.doi.org/10.1002/anie.201813125DOI Listing
March 2019

Ongoing change of severe hand, foot, and mouth disease pathogens in Yunnan, China, 2012 to 2016.

J Med Virol 2019 05 12;91(5):881-885. Epub 2019 Jan 12.

The Department of Medical Genetics, Institute of Medical Biology, Chinese Academy of Medical Sciences, and Peking Union Medical College, Kunming, China.

Hand, foot, and mouth disease (HFMD) is a common infectious disease caused by enteroviruses (EVs). In this study, a total of 341 children with serious HFMD were admitted to a pediatric hospital in Yunnan, China in 2012 to 2016. EVs were detected in 283 specimens (83.0%) and were assigned to 17 EV types. Enterovirus A71 (EV-A71) was predominant, accounting for 41.6%, and was followed by coxsackievirus A16 (CV-A16; 18.8%), CV-A6 (9.1%), CV-A10 and E-9 (2.9%), CV-B5 (1.8%), CV-A9 (1.2%), E-30 (0.9%), E-18, CV-A4, C-B3, and CV-A2 (0.6%) and other EV types such as CV-A8, CV-A14, E-14, E-11, and CV-B4 (0.3%). All of the EV-A71 isolates belonged to C4a; the CV-A16 belonged to B1b or B1a, although the B1b strains were predominant; and CV-A6 belonged to D3. In 2012 to 2014, E-9 was the third most frequent serotype (8.2%, 5.0%, and 6.5%, respectively). E-9 was not detected in 2015 and 2016. CV-A6 was not detected in 2012 but was the second most frequent serotype (25.3%) in 2015. Active etiological surveillance of HFMD makes it necessary to be aware of these emerging pathogens.
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http://dx.doi.org/10.1002/jmv.25393DOI Listing
May 2019

Helicity adaptation within a quadruply stranded helicate by encapsulation.

Chem Commun (Camb) 2018 Nov;54(95):13447-13450

Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, P. R. China.

The helicity of a quadruply stranded M2L4 helicate consisting of an aromatic amide bidendate ligand is flexible due to the twisting of the amide moieties and can be tuned by the encapsulated anions. This study reveals the multiple interplays and complementarities between the anions as well as between the anions and the helicate, which are synthetically responsive to the ultimate conformation of the helicate.
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http://dx.doi.org/10.1039/c8cc07932cDOI Listing
November 2018

Skin Disease Recognition Method Based on Image Color and Texture Features.

Comput Math Methods Med 2018 26;2018:8145713. Epub 2018 Aug 26.

School of Electrical and Engineer, Anhui Polytechnic University, Wuhu 241000, China.

Skin diseases have a serious impact on people's life and health. Current research proposes an efficient approach to identify singular type of skin diseases. It is necessary to develop automatic methods in order to increase the accuracy of diagnosis for multitype skin diseases. In this paper, three type skin diseases such as herpes, dermatitis, and psoriasis skin disease could be identified by a new recognition method. Initially, skin images were preprocessed to remove noise and irrelevant background by filtering and transformation. Then the method of grey-level co-occurrence matrix (GLCM) was introduced to segment images of skin disease. The texture and color features of different skin disease images could be obtained accurately. Finally, by using the support vector machine (SVM) classification method, three types of skin diseases were identified. The experimental results demonstrate the effectiveness and feasibility of the proposed method.
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http://dx.doi.org/10.1155/2018/8145713DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6129338PMC
December 2018

Synaptic Vesicle Endocytosis in Different Model Systems.

Front Cell Neurosci 2018 28;12:171. Epub 2018 Jun 28.

Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD, United States.

Neurotransmission in complex animals depends on a choir of functionally distinct synapses releasing neurotransmitters in a highly coordinated manner. During synaptic signaling, vesicles fuse with the plasma membrane to release their contents. The rate of vesicle fusion is high and can exceed the rate at which synaptic vesicles can be re-supplied by distant sources. Thus, local compensatory endocytosis is needed to replenish the synaptic vesicle pools. Over the last four decades, various experimental methods and model systems have been used to study the cellular and molecular mechanisms underlying synaptic vesicle cycle. Clathrin-mediated endocytosis is thought to be the predominant mechanism for synaptic vesicle recycling. However, recent studies suggest significant contribution from other modes of endocytosis, including fast compensatory endocytosis, activity-dependent bulk endocytosis, ultrafast endocytosis, as well as kiss-and-run. Currently, it is not clear whether a universal model of vesicle recycling exist for all types of synapses. It is possible that each synapse type employs a particular mode of endocytosis. Alternatively, multiple modes of endocytosis operate at the same synapse, and the synapse toggles between different modes depending on its activity level. Here we compile review and research articles based on well-characterized model systems: frog neuromuscular junctions, neuromuscular junctions, neuromuscular junctions, lamprey reticulospinal giant axons, goldfish retinal ribbon synapses, the calyx of Held, and rodent hippocampal synapses. We will compare these systems in terms of their known modes and kinetics of synaptic vesicle endocytosis, as well as the underlying molecular machineries. We will also provide the future development of this field.
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http://dx.doi.org/10.3389/fncel.2018.00171DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6031744PMC
June 2018

BmSUC1 is essential for glycometabolism modulation in the silkworm, Bombyx mori.

Biochim Biophys Acta Gene Regul Mech 2018 06 14;1861(6):543-553. Epub 2018 Apr 14.

School of Life Sciences, Anhui Agricultural University, Hefei 230036, Anhui, China; Anhui International Joint Research and Development Center of Sericulture Resources Utilization, Hefei 230036, Anhui, China. Electronic address:

Sucrose is the most commonly transported sugar in plants and is easily assimilated by insects to fulfill the requirement of physiological metabolism. BmSuc1 is a novel animal β-fructofuranosidase (β-FFase, EC 3.2.1.26)-encoding gene that was firstly cloned and identified in silkworm, Bombyx mori. BmSUC1 was presumed to play an important role in the silkworm-mulberry enzymatic adaptation system by effectively hydrolyzing sucrose absorbed from mulberry leaves. However, this has not been proved with direct evidence thus far. In this study, we investigated sucrose hydrolysis activity in the larval midgut of B. mori by inhibition tests and found that sucrase activity mainly stemmed from β-FFase, not α-glucosidase. Next, we performed shRNA-mediated transgenic RNAi to analyze the growth characteristics of silkworm larvae and variations in glycometabolism in vivo in transgenic silkworms. The results showed that in the RNAi-BmSuc1 transgenic line, larval development was delayed, and their body size was markedly reduced. Finally, the activity of several disaccharidases alone in the midgut and the sugar distribution, total sugar and glycogen in the midgut, hemolymph and fat body were then determined and compared. Our results demonstrated that silencing BmSuc1 significantly reduced glucose and apparently activated maltase and trehalase in the midgut. Together with a clear decrease in both glycogen and trehalose in the fat body, we conclude that BmSUC1 acts as an essential sucrase by directly modulating the degree of sucrose hydrolysis in the silkworm larval midgut, and insufficient sugar storage in the fat body may be responsible for larval malnutrition and abnormal petite phenotypes.
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http://dx.doi.org/10.1016/j.bbagrm.2018.04.002DOI Listing
June 2018
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