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1.
J Synchrotron Radiat ; 30(Pt 2): 347-358, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36891848

ABSTRACT

There is an increasing demand for simple and efficient sample delivery technology to match the rapid development of serial crystallography and its wide application in analyzing the structural dynamics of biological macromolecules. Here, a microfluidic rotating-target device is presented, capable of three-degrees-of-freedom motion, including two rotational degrees of freedom and one translational degree of freedom, for sample delivery. Lysozyme crystals were used as a test model with this device to collect serial synchrotron crystallography data and the device was found to be convenient and useful. This device enables in situ diffraction from crystals in a microfluidic channel without the need for crystal harvesting. The circular motion ensures that the delivery speed can be adjusted over a wide range, showing its good compatibility with different light sources. Moreover, the three-degrees-of-freedom motion guarantees the full utilization of crystals. Hence, sample consumption is greatly reduced, and only 0.1 mg of protein is consumed in collecting a complete dataset.

2.
Biomacromolecules ; 24(1): 1-18, 2023 01 09.
Article in English | MEDLINE | ID: mdl-36507729

ABSTRACT

Amyloid protein cross-seeding is a peculiar phenomenon of cross-spreading among different diseases. Unlike traditional infectious ones, diseases caused by amyloid protein cross-seeding are spread by misfolded proteins instead of pathogens. As a consequence of the interactions among misfolded heterologous proteins or polypeptides, amyloid protein cross-seeding is considered to be the crucial cause of overlapping pathological transmission between various protein misfolding disorders (PMDs) in multiple tissues and cells. Here, we briefly review the phenomenon of cross-seeding among amyloid proteins. As an interesting example worth mentioning, the potential links between the novel coronavirus pneumonia (COVID-19) and some neurodegenerative diseases might be related to the amyloid protein cross-seeding, thus may cause an undesirable trend in the incidence of PMDs around the world. We then summarize the theoretical models as well as the experimental techniques for studying amyloid protein cross-seeding. Finally, we conclude with an outlook on the challenges and opportunities for basic research in this field. Cross-seeding of amyloid opens up a new perspective in our understanding of the process of amyloidogenesis, which is crucial for the development of new treatments for diseases. It is therefore valuable but still challenging to explore the cross-seeding system of amyloid protein as well as to reveal the structural basis and the intricate processes.


Subject(s)
COVID-19 , Neurodegenerative Diseases , Humans , Amyloidogenic Proteins , Amyloid beta-Peptides/chemistry , Amyloid/metabolism
3.
Mol Carcinog ; 60(8): 538-555, 2021 08.
Article in English | MEDLINE | ID: mdl-34062009

ABSTRACT

Triple-negative breast cancer (TNBC) is the most malignant subtype of breast cancer. Some microRNAs (miRNAs) were abnormally expressed in TNBC, and they are closely related to the occurrence and progression of TNBC. Here, we found that miR-506 was significantly downregulated in TNBC and relatively lower miR-506 expression predicted a poorer prognosis. Moreover, we found that miR-506 could inhibit MDA-MB-231 cell viability, colony formation, migration, and invasion, and suppress the ERK/Fos oncogenic signaling pathway through upregulating its direct target protein proenkephalin (PENK). Therefore, miR-506 was proposed as a nucleic acid drug for TNBC therapy. However, miRNA is unstable in vivo, which limiting its application as a therapeutic drug via conventional oral or injected therapies. Here, a gelatin nanosphere (GN) delivery system was applied for the first time to load exogenous miRNA. Exogenous miR-506 mimic was loaded on GNs and injected into the in situ TNBC animal model, and the miR-506 could achieve sustained and controlled release. The results confirmed that overexpression of miR-506 and PENK in vivo through loading on GNs inhibited in situ triple-negative breast tumor growth and metastasis significantly in the xenograft model. Moreover, we indicated that the ERK/Fos signaling pathway was intensively inactivated after overexpression of miR-506 and PENK both in vitro and in vivo, which was further validated by the ERK1/2-specific inhibitor SCH772984. In conclusion, this study demonstrates that miR-506-loaded GNs have great potential in anti-TNBC aggressiveness therapy.


Subject(s)
Enkephalins/genetics , Extracellular Signal-Regulated MAP Kinases/metabolism , Gene Expression Regulation, Neoplastic , MicroRNAs/genetics , Protein Precursors/genetics , Proto-Oncogene Proteins c-fos/metabolism , Signal Transduction , Triple Negative Breast Neoplasms/genetics , Triple Negative Breast Neoplasms/metabolism , Animals , Cell Line, Tumor , Disease Models, Animal , Disease Progression , Female , Gelatin , Gene Transfer Techniques , Humans , Mice , MicroRNAs/administration & dosage , Nanospheres , Triple Negative Breast Neoplasms/pathology , Xenograft Model Antitumor Assays
4.
Appl Microbiol Biotechnol ; 105(7): 2759-2773, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33683398

ABSTRACT

The self-assembly of biomacromolecules is an extremely important process. It is potentially useful in the fields of life science and materials science. To carry out the study on the self-assembly of proteins, it is necessary to find out the suitable self-assembly conditions, which have always been a challenging task in practice. Inspired by the screening technique in the field of protein crystallization, we proposed using the same screening technique for seeking suitable protein self-assembly conditions. Based on this consideration, we selected 5 proteins (ß-lactoglobulin, hemoglobin, pepsin, lysozyme, α-chymotrypsinogen (II) A) together with 5 screening kits (IndexTM, BML, Morpheus, JCSG, PEG/Ion ScreenTM) to investigate the performance of these crystallization screening techniques in order to discover new optimized conditions of protein self-assembly. The screens were all kept at 293 K for certain days, and were analyzed using optical microscope, scanning electron microscope, transmission electron microscope, atomic force microscope, fluorescence microscope, and atomic absorption spectroscope. The results demonstrated that the method of protein crystallization screening can be successfully applied in the screening of self-assembly conditions. This method is fast, high throughput, and easily implemented in an automated system, with a low protein consumption feature. These results suggested that such strategy can be applied to finding new conditions or forms in routine research of protein self-assembly. KEY POINTS: • Protein crystallization screening method is successfully applied in the screening of self-assembly conditions. • This screening method can be applied on various kinds of proteins and possess a feature of low protein consumption. • This screening method is fast, high throughput, and easily implemented in an automated system.


Subject(s)
Proteins , Crystallization
5.
Bioelectromagnetics ; 39(6): 428-440, 2018 Sep.
Article in English | MEDLINE | ID: mdl-29873401

ABSTRACT

Large gradient high magnetic field (LG-HMF) is a powerful tool to study the effects of altered gravity on organisms. In our study, a platform for the long-term culture of aquatic organisms was designed based on a special superconducting magnet with an LG-HMF, which can provide three apparent gravity levels (µ g, 1 g, and 2 g), along with a control condition on the ground. Planarians, Dugesia japonica, were head-amputated and cultured for 5 days in a platform for head reconstruction. After planarian head regeneration, all samples were taken out from the superconducting magnet for a behavioral test under geomagnetic field and normal gravity conditions. To analyze differences among the four groups, four aspects of the planarians were considered, including head regeneration rate, phototaxis response, locomotor velocity, and righting behavior. Data showed that there was no significant difference in the planarian head regeneration rate under simulated altered gravity. According to statistical analysis of the behavioral test, all of the groups had normal functioning of the phototaxis response, while the planarians that underwent head reconstruction under the microgravity environment had significantly slower locomotor velocity and spent more time in righting behavior. Furthermore, histological staining and immunohistochemistry results helped us reveal that the locomotor system of planarians was affected by the simulated microgravity environment. We further demonstrated that the circular muscle of the planarians was weakened (hematoxylin and eosin staining), and the epithelial cilia of the planarians were reduced (anti-acetylated tubulin staining) under the simulated microgravity environment. Bioelectromagnetics. 2018;39:428-440. © 2018 Wiley Periodicals, Inc.


Subject(s)
Magnetic Fields , Planarians/physiology , Regeneration , Animals , Aquatic Organisms , Gravitation , Immunohistochemistry , Movement , Phototaxis , Planarians/anatomy & histology , Time Factors
6.
Int J Biol Macromol ; 256(Pt 1): 128370, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38000594

ABSTRACT

Infection poses a significant barrier to effective wound repair, leading to increased inflammatory responses that ultimately result in incomplete and prolonged wound healing. To address this challenge, numerous antibacterial ingredients have been incorporated into dressings to inhibit wound infection. Our previous work demonstrated that lysozyme/silver nanoparticles (LYZ/AgNPs) complexes, prepared using an eco-friendly one-step aqueous method, exhibited excellent antibacterial efficacy with favorable biosafety. To further explore its potential application in advancing wound healing, calcium alginate (CA) with good porosity, water absorption, and water retention capacities was formulated with LYZ/AgNPs to prepare composite sponge (CA/LYZ/AgNPs). As expected, in vivo experiments involving full-thickness skin wound and scald wound healing experiments demonstrated that CA-LYZ-AgNPs composite sponges with excellent biocompatibility exhibited remarkable antibacterial activity against gram-positive bacteria, gram-negative bacteria and fungi, and outperformed the wound healing process efficacy of other commercially available AgNPs-loaded wound dressings. In summary, this work introduces a CA/LYZ/AgNPs sponge featuring exceptional antibacterial efficacy and biocompatibility, thus holding promising potential in wound care applications.


Subject(s)
Alginates , Metal Nanoparticles , Alginates/pharmacology , Silver/pharmacology , Muramidase , Anti-Bacterial Agents/pharmacology , Wound Healing , Bandages , Water
7.
Int J Biol Macromol ; 273(Pt 1): 133074, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38866293

ABSTRACT

Triple-negative breast cancer (TNBC) is the most malignant subtype of breast cancer, has a poor prognosis and limited access to efficient targeted treatments. Chronic unpredictable mild stress (CUMS) is highly risk factor for TNBC occurrence and development. Type X collagen (COL10A1), a crucial protein component of the extracellular matrix, ranks second among all aberrantly expressed genes in TNBC, and it is significantly up-regulated under CUMS. Nevertheless, the impact of CUMS and COL10A1 on TNBC, along with the underlying mechanisms are still unclear. In this research, we studied the effect of CUMS-induced norepinephrine (NE) elevation on TNBC, and uncovered that it notably enhanced TNBC cell proliferation, migration, and invasion in vitro, and also fostering tumor growth and lung metastasis in vivo. Additionally, our investigation found that COL10A1 directly interacted with integrin subunit beta 1 (ITGB1), then activates the downstream PI3K/AKT signaling pathway, thereby promoting TNBC growth and metastasis, while it was reversed by knocking down of COL10A1 or ITGB1. Our study demonstrated that the TNBC could respond to CUMS, and advocate for COL10A1 as a pivotal therapeutic target in TNBC treatment.


Subject(s)
Cell Proliferation , Collagen Type X , Integrin beta1 , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , Signal Transduction , Triple Negative Breast Neoplasms , Triple Negative Breast Neoplasms/pathology , Triple Negative Breast Neoplasms/genetics , Triple Negative Breast Neoplasms/drug therapy , Triple Negative Breast Neoplasms/metabolism , Integrin beta1/metabolism , Integrin beta1/genetics , Humans , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Female , Animals , Cell Line, Tumor , Signal Transduction/drug effects , Cell Proliferation/drug effects , Collagen Type X/metabolism , Collagen Type X/genetics , Disease Progression , Mice , Cell Movement/drug effects , Gene Expression Regulation, Neoplastic/drug effects , Gene Knockdown Techniques
8.
World J Clin Cases ; 12(4): 787-794, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38322674

ABSTRACT

BACKGROUND: Fulminant type 1 diabetes mellitus (FT1DM) that occurs during pregnancy or the perinatal period is known as pregnancy-related FT1DM (PF), always without history of abnormal glucose metabolism. Here, we present four patients who developed FT1DM during treatment but were first diagnosed with gestational diabetes mellitus (GDM). CASE SUMMARY: The clinical data of four patients with GDM combined with FT1DM admitted to our hospital between July 2018 and April 2021 were collected, and the patients and their infants were followed up. All patients were diagnosed with GDM during the second trimester and were treated. The blood glucose level elevated suddenly during the third trimester and then were diagnosed with FT1DM. Two patients had an insulin allergy, and two had symptoms of upper respiratory tract infection before onset. One patient developed ketoacidosis, and three developed ketosis. Two patients had cesarean section deliveries, and two had vaginal deliveries. The growth and development of the infants were normal. C-peptide levels were lower than those at onset, suggesting progressive impairment of islet function. The frequencies of the DRB1 09:01, DQB1 03: 03, DQA1 03:02, DPA1 01:03, DPA1 02:02, DPB1 05:01, DRB4 01:03, G 01:01, and G 01:04 human leukocyte antigen (HLA)-G alleles were high in the present study. CONCLUSION: In comparison with pregnancy-associated FT1DM (PF), patients with GDM combined with FT1DM had an older age of onset, higher body mass index, slower onset, fewer prodromal symptoms, and less acidosis. The pathogenesis may be due to various factors affecting the already fragile ß-cells of GDM patients with genetically susceptible class II HLA genotypes. We speculate that GDM combined with FT1DM during pregnancy, referred to as "double diabetes," is a subtype of PF with its own unique characteristics that should be investigated further.

9.
Biomater Sci ; 12(5): 1332-1334, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38362932

ABSTRACT

Correction for 'MiR-4458-loaded gelatin nanospheres target COL11A1 for DDR2/SRC signaling pathway inactivation to suppress the progression of estrogen receptor-positive breast cancer' by Jie Liu et al., Biomater. Sci., 2022, 10, 4596-4611, https://doi.org/10.1039/D2BM00543C.

10.
Acta Crystallogr D Biol Crystallogr ; 69(Pt 10): 1901-10, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24100310

ABSTRACT

High-quality crystals are key to obtaining accurate three-dimensional structures of proteins using X-ray diffraction techniques. However, obtaining such protein crystals is often a challenge. Several containerless crystallization techniques have been reported to have the ability to improve crystal quality, but it is unknown which is the most favourable way to grow high-quality protein crystals. In this paper, a quality comparison of protein crystals which were grown under three containerless conditions provided by diamagnetic levitation, silicone oil and agarose gel was conducted. A control experiment on a vessel wall was also simultaneously carried out. Seven different proteins were crystallized under the four conditions, and the crystal quality was assessed in terms of the resolution limit, the mosaicity and the Rmerge. It was found that the crystals grown under the three containerless conditions demonstrated better morphology than those of the control. X-ray diffraction data indicated that the quality of the crystals grown under the three containerless conditions was better than that of the control. Of the three containerless crystallization techniques, the diamagnetic levitation technique exhibited the best performance in enhancing crystal quality. This paper is to our knowledge the first report of improvement of crystal quality using a diamagnetic levitation technique. Crystals obtained from agarose gel demonstrated the second best improvement in crystal quality. The study indicated that the diamagnetic levitation technique is indeed a favourable method for growing high-quality protein crystals, and its utilization is thus potentially useful in practical efforts to obtain well diffracting protein crystals.


Subject(s)
Crystallography, X-Ray , Gravitation , Magnetic Resonance Spectroscopy , Photoelectron Spectroscopy , Proteins/chemistry , Sepharose/standards , Silicone Oils/standards , Animals , Chickens , Crystallization/methods , Crystallization/standards , Crystallography, X-Ray/methods , Crystallography, X-Ray/standards , Escherichia coli Proteins/chemistry , Proteins/standards , Quality Control , Trichosanthes , X-Ray Diffraction/methods , X-Ray Diffraction/standards
11.
Food Funct ; 14(10): 4621-4631, 2023 May 22.
Article in English | MEDLINE | ID: mdl-37158592

ABSTRACT

The abnormal accumulation of fused in sarcoma (FUS) is a pathological hallmark in a proportion of patients with frontotemporal dementia and amyotrophic lateral sclerosis. Therefore, the clearance of FUS aggregates is a possible therapeutic strategy for FUS-associated neurodegenerative diseases. This study reports that curcumin can strongly suppress FUS droplet formation and stress granule aggregation of FUS. Fluorescence spectra and isothermal titration calorimetry showed that curcumin can bind FUS through hydrophobic interactions, thereby reducing the ß-sheet content of FUS. Aggregated FUS sequesters pyruvate kinase, leading to reduced ATP levels. However, results from a metabolomics study revealed that curcumin changed the metabolism pattern and differentially expressed metabolites were enriched in glycolysis. Curcumin attenuated FUS aggregation-mediated sequestration of pyruvate kinase and restored cellular metabolism, consequently increasing ATP levels. These results indicate that curcumin is a potent inhibitor of FUS liquid-liquid phase separation and provide novel insights into the effect of curcumin in ameliorating abnormal metabolism.


Subject(s)
Curcumin , Frontotemporal Dementia , Sarcoma , Humans , Pyruvate Kinase/genetics , Pyruvate Kinase/metabolism , Curcumin/pharmacology , Frontotemporal Dementia/metabolism , Adenosine Triphosphate , Mutation , RNA-Binding Protein FUS/chemistry , RNA-Binding Protein FUS/genetics , RNA-Binding Protein FUS/metabolism
12.
Research (Wash D C) ; 6: 0146, 2023.
Article in English | MEDLINE | ID: mdl-37228640

ABSTRACT

The biological effects of magnetic fields (MFs) have been a controversial issue. Fortunately, in recent years, there has been increasing evidence that MFs do affect biological systems. However, the physical mechanism remains unclear. Here, we show that MFs (16 T) reduce apoptosis in cell lines by inhibiting liquid-liquid phase separation (LLPS) of Tau-441, suggesting that the MF effect on LLPS may be one of the mechanisms for understanding the "mysterious" magnetobiological effects. The LLPS of Tau-441 occurred in the cytoplasm after induction with arsenite. The phase-separated droplets of Tau-441 recruited hexokinase (HK), resulting in a decrease in the amount of free HK in the cytoplasm. In cells, HK and Bax compete to bind to the voltage-dependent anion channel (VDAC I) on the mitochondrial membrane. A decrease in the number of free HK molecules increased the chance of Bax binding to VDAC I, leading to increased Bax-mediated apoptosis. In the presence of a static MF, LLPS was marked inhibited and HK recruitment was reduced, resulting in an increased probability of HK binding to VDAC I and a decreased probability of Bax binding to VDAC I, thus reducing Bax-mediated apoptosis. Our findings revealed a new physical mechanism for understanding magnetobiological effects from the perspective of LLPS. In addition, these results show the potential applications of physical environments, such as MFs in this study, in the treatment of LLPS-related diseases.

13.
ACS Appl Mater Interfaces ; 15(43): 49931-49942, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37856675

ABSTRACT

The skin secretion of Andrias davidianus (SSAD) is a novel biological adhesive raw material under development. This material exhibits robust adhesion while maintaining the flexibility of the wound. It also has the potential for large-scale production, making it promising for practical application explore. Hence, in-depth research on methods to fine-tune SSAD properties is of great importance to promote its practical applications. Herein, we aim to enhance the adhesive and healing properties of SSAD by incorporating functional components. To achieve this goal, we selected 3,4-dihydroxy-l-phenylalanine and vaccarin as the functional components and mixed them with SSAD, resulting in a new bioadhesive, namely, a formulation termed "enhanced SSAD" (ESSAD). We found that the ESSAD exhibited superior adhesive properties, and its adhesive strength was improved compared with the SSAD. Moreover, ESSAD demonstrated a remarkable ability to promote wound healing. This study presents an SSAD-based bioadhesive formulation with enhanced properties, affirming the feasibility of developing SSAD-based adhesive materials with excellent performance and providing new evidence for the application of SSAD. This study also aims to show that SSAD can be mixed with other substances, and addition of effective components to SSAD can be studied to further adjust or improve its performance.


Subject(s)
Tissue Adhesives , Wound Healing , Humans , Adhesives/pharmacology , Skin , Tissue Adhesives/pharmacology , Tissue Adhesions , Mucus , Hydrogels
14.
J Adv Res ; 2023 Dec 29.
Article in English | MEDLINE | ID: mdl-38159844

ABSTRACT

INTRODUCTION: The population of Taiwan has a long history of ethno-cultural evolution. The Taiwanese population was isolated from other large populations such as the European, Han Chinese, and Japanese population. The Taiwan Biobank (TWB) project has built a nationwide database, particularly for personal whole-genome sequence (WGS) to facilitate basic and clinical collaboration nationally and internationally, making it one of the most valuable public datasets of the East Asian population. OBJECTIVES: This study provides comprehensive medical genomic findings from TWB WGS data, for better characterization of disease susceptibility and the choice of ideal treatment regimens in Taiwanese population. METHODS: We reanalyzed 1496 WGS using a PrecisionFDA Truth challenge winner method Sentieon DNAscope. Single nucleotide variants (SNV) and small insertions/deletions (INDEL) were benchmarked. We also analyzed pharmacogenomic (PGx) drug-associated alleles, and copy number variants (CNV). Multiple practicing clinicians reviewed and curated the clinically significant variants. Variant annotations can be browsed at TaiwanGenomes (https://genomes.tw). RESULTS: We found that each participant had an average of 6,870.7 globally novel variants and 75.3% (831/1103) of the participants harbored at least one PharmGKB-selected high evidence level human leukocyte antigen (HLA) risk allele. 54 PharmGKB-reported high-level instances of evidence of Cytochrome P450 variant-drug pairs, with a population frequency of over 13.2%. We also identified 23 variants in the ACMG secondary finding V3 gene list from 25 participants, suggesting that 1.67% (25/1496) of the population is harboring at least one medical actionable variant. Our carrier status analyses suggest that one in 25 couples (3.94%) would risk having offspring with at least one pathogenic variant, which is in line with rates found in Japan and Singapore. For pathogenic CNV, we detected 6.88% and 2.02% carrier rates for alpha thalassemia and spinal muscular atrophy, respectively. CONCLUSION: Our study highlights the overall medical insights of a complete Taiwanese genomic profile.

15.
Hum Mol Genet ; 19(14): 2917-25, 2010 Jul 15.
Article in English | MEDLINE | ID: mdl-20460270

ABSTRACT

Biliary atresia (BA) is characterized by the progressive fibrosclerosing obliteration of the extrahepatic biliary system during the first few weeks of life. Despite early diagnosis and prompt surgical intervention, the disease progresses to cirrhosis in many patients. The current theory for the pathogenesis of BA proposes that during the perinatal period, a still unknown exogenous factor meets the innate immune system of a genetically predisposed individual and induces an uncontrollable and potentially self-limiting immune response, which becomes manifest in liver fibrosis and atresia of the extrahepatic bile ducts. Genetic factors that could account for the disease, let alone for its high incidence in Chinese, are to be investigated. To identify BA susceptibility loci, we carried out a genome-wide association study (GWAS) using the Affymetrix 5.0 and 500 K marker sets. We genotyped nearly 500 000 single-nucleotide polymorphisms (SNPs) in 200 Chinese BA patients and 481 ethnically matched control subjects. The 10 most BA-associated SNPs from the GWAS were genotyped in an independent set of 124 BA and 90 control subjects. The strongest overall association was found for rs17095355 on 10q24, downstream XPNPEP1, a gene involved in the metabolism of inflammatory mediators. Allelic chi-square test P-value for the meta-analysis of the GWAS and replication results was 6.94 x 10(-9). The identification of putative BA susceptibility loci not only opens new fields of investigation into the mechanisms underlying BA but may also provide new clues for the development of preventive and curative strategies.


Subject(s)
Biliary Atresia/genetics , Chromosomes, Human, Pair 10 , Genetic Loci , Genetic Predisposition to Disease , Asian People/genetics , Case-Control Studies , Chromosome Mapping , Chromosomes, Human, Pair 10/genetics , Female , Gene Frequency , Genome-Wide Association Study , Humans , Linkage Disequilibrium , Male , Polymorphism, Single Nucleotide
16.
Proc Natl Acad Sci U S A ; 106(8): 2694-9, 2009 Feb 24.
Article in English | MEDLINE | ID: mdl-19196962

ABSTRACT

Hirschsprung's disease (HSCR), or aganglionic megacolon, is a congenital disorder characterized by the absence of enteric ganglia in variable portions of the distal intestine. RET is a well-established susceptibility locus, although existing evidence strongly suggests additional loci contributing to sporadic HSCR. To identify these additional genetic loci, we carried out a genome-wide association study using the Affymetrix 500K marker set. We successfully genotyped 293,836 SNPs in 181 Chinese subjects with sporadic HSCR and 346 ethnically matched control subjects. The SNPs most associated with HSCR were genotyped in an independent set of 190 HSCR and 510 control subjects. Aside from SNPs in RET, the strongest overall associations in plausible candidate genes were found for 2 SNPs located in intron 1 of the neuregulin1 gene (NRG1) on 8p12, with rs16879552 and rs7835688 yielding odds ratios of 1.68 [CI(95%):(1.40, 2.00), P = 1.80 x 10(-8)] and 1.98 [CI(95%):(1.59, 2.47), P = 1.12 x 10(-9)], respectively, for the heterozygous risk genotypes under an additive model. There was also a significant interaction between RET and NRG1 (P = 0.0095), increasing the odds ratio 2.3-fold to 19.53 for the RET rs2435357 risk genotype (TT) in the presence of the NRG1 rs7835688 heterozygote, indicating that NRG1 is a modifier of HSRC penetrance. Our highly significant association findings are backed-up by the important role of NRG1 as regulator of the development of the enteric ganglia precursors. The identification of NRG1 as an additional HSCR susceptibility locus not only opens unique fields of investigation into the mechanisms underlying the HSCR pathology, but also the mechanisms by which a discrete number of loci interact with each other to cause disease.


Subject(s)
Genetic Predisposition to Disease , Genome, Human , Hirschsprung Disease/genetics , Nerve Tissue Proteins/genetics , Female , Genetic Markers , Genome-Wide Association Study , Humans , Male , Neuregulin-1 , Polymorphism, Single Nucleotide , Proto-Oncogene Proteins c-ret/genetics
17.
J Acoust Soc Am ; 131(4): 3164-72, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22501088

ABSTRACT

This paper reports on an ultrasonic levitation system developed for crystallization from solution in a containerless condition. The system has been proven to be able to levitate droplets stably and grow crystals rapidly and freely from a levitated droplet. Crystals of four samples, including NaCl, NH(4)Cl, lysozyme, and proteinase K, were obtained successfully utilizing the system. The studies showed that the crystals obtained from the acoustically levitated droplets all exhibited higher growth rates, larger sizes, better shapes, fewer crystals, as well as fewer twins and shards, compared with the control on a vessel wall. The results indicated that containerless ultrasonic levitation could play a key role in improving the crystallization of both inorganic salts and proteins. The ultrasonic levitation system could be used as a ground-based microgravity simulation platform, which could swiftly perform crystallization and screening of crystallization conditions for space crystallization and other ground-based containerless techniques. Moreover, the approach could also be conveniently applied to researching the dynamics and mechanism of crystallization. In addition, the device could be used for the preparation of high-purity materials, analysis of minute or poisonous samples, study of living cells, environmental monitoring, and so on.

18.
Int J Mol Sci ; 13(8): 9514-9526, 2012.
Article in English | MEDLINE | ID: mdl-22949812

ABSTRACT

The protein structural entries grew far slower than the sequence entries. This is partly due to the bottleneck in obtaining diffraction quality protein crystals for structural determination using X-ray crystallography. The first step to achieve protein crystallization is to find out suitable chemical reagents. However, it is not an easy task. Exhausting trial and error tests of numerous combinations of different reagents mixed with the protein solution are usually necessary to screen out the pursuing crystallization conditions. Therefore, any attempts to help find suitable reagents for protein crystallization are helpful. In this paper, an analysis of the relationship between the protein sequence similarity and the crystallization reagents according to the information from the existing databases is presented. We extracted information of reagents and sequences from the Biological Macromolecule Crystallization Database (BMCD) and the Protein Data Bank (PDB) database, classified the proteins into different clusters according to the sequence similarity, and statistically analyzed the relationship between the sequence similarity and the crystallization reagents. The results showed that there is a pronounced positive correlation between them. Therefore, according to the correlation, prediction of feasible chemical reagents that are suitable to be used in crystallization screens for a specific protein is possible.


Subject(s)
Databases, Protein , Multiprotein Complexes/chemistry , Proteins/chemistry , Animals , Crystallization , Crystallography, X-Ray , Humans , Sequence Homology
19.
Int J Mol Sci ; 13(12): 16916-28, 2012 Dec 11.
Article in English | MEDLINE | ID: mdl-23443127

ABSTRACT

The effect of magnetic fields on water is still a highly controversial topic despite the vast amount of research devoted to this topic in past decades. Enhanced water evaporation in a magnetic field, however, is less disputed. The underlying mechanism for this phenomenon has been investigated in previous studies. In this paper, we present an investigation of the evaporation of water in a large gradient magnetic field. The evaporation of pure water at simulated gravity positions (0 gravity level (ab. g), 1 g, 1.56 g and 1.96 g) in a superconducting magnet was compared with that in the absence of the magnetic field. The results showed that the evaporation of water was indeed faster in the magnetic field than in the absence of the magnetic field. Furthermore, the amount of water evaporation differed depending on the position of the sample within the magnetic field. In particular, the evaporation at 0 g was clearly faster than that at other positions. The results are discussed from the point of view of the evaporation surface area of the water/air interface and the convection induced by the magnetization force due to the difference in the magnetic susceptibility of water vapor and the surrounding air.


Subject(s)
Magnetic Fields , Models, Chemical , Water/chemistry
20.
Int J Pharm ; 627: 122200, 2022 Nov 05.
Article in English | MEDLINE | ID: mdl-36155893

ABSTRACT

Staphylococcus aureus (S. aureus) infection, especially its drug-resistant bacterial infection, is a great challenge often faced by clinicians and patients, and it is also one of the most important threats to public health. Finding a safe and effective antibacterial agent is of great significance for the prevention and treatment of S. aureus infection. Lysozyme is known to have antibacterial effects against Gram-positive bacteria including S. aureus. Here, high-quality lysozyme with a purity of more than 99% and an activity of more than 60, 000 U/mg was prepared from egg white, which showed excellent antibacterial activity against three strains of S. aureus, especially against MRSA. Furthermore, an antibacterial cream loaded with lysozyme was prepared and tested in scald wound healing. The lysozyme-loaded cream exhibited the effect of preventing wound infection and promoting wound healing on scalds, and no toxicity was found in animal organs. Overall, lysozyme showed great application potential in the prevention and treatment of infections caused by S. aureus and scalded wound healing. The most remarkable discovery in this work is the unexpectedly powerful inhibitory effect of lysozyme on the drug-resistant bacterial, especially MRSA, which is usually very difficult to deal with using normal antibacterial drugs.


Subject(s)
Burns , Dermatologic Agents , Methicillin-Resistant Staphylococcus aureus , Staphylococcal Infections , Animals , Staphylococcus aureus , Microbial Sensitivity Tests , Muramidase/pharmacology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Wound Healing , Dermatologic Agents/pharmacology , Burns/drug therapy
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