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1.
J Matern Fetal Neonatal Med ; 36(2): 2270761, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37848386

RESUMO

Background: Macrosomia is a common disorder that occurs during pregnancy. We investigated the comprehensive metabolite profiles of pregnant maternal and fetal sera in normoglycemic macrosomia in a Chinese population. Methods: Forty pregnant women and their fetuses were included in the study (twenty macrosomia patients and twenty normal-weight controls). Maternal and umbilical cord serum metabolites were identified using ultra-performance liquid chromatography coupled with tandem mass spectrometry. Results: In total, 203 metabolites were identified. Lipids and lipid-like molecules were the predominant metabolites. Fifty-three metabolites with significant differences were obtained in the maternal samples. In the macrosomia group, the levels of docosahexaenoic acid, eicosapentaenoic acid, and arachidonic acid were significantly higher than those in the control group. Umbilical cord serum samples were obtained for 24 different metabolites. The maternal-fetal gradient of polyunsaturated fatty acids was decreased in the macrosomia group. Aconitic acid, citric acid, isocitric acid, 2-methylhexanoic acid, and 12-hydroxystearic acid were the common differential metabolites in the maternal and umbilical cord serum samples. Conclusion: There were obvious metabolic abnormalities in the sera of pregnant women and fetuses with macrosomia. Lipids and lipid-like molecules were the predominant differential metabolites but had different classifications in the maternal and umbilical cord serum. These results may provide new insights into the long-term metabolic disorders associated with macrosomia.


Assuntos
Sangue Fetal , Macrossomia Fetal , Humanos , Gravidez , Feminino , Macrossomia Fetal/epidemiologia , Sangue Fetal/química , Metabolômica , Ácidos Docosa-Hexaenoicos/metabolismo , Cromatografia Líquida
2.
Int J Pharm ; 599: 120449, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33711472

RESUMO

Intracellular pathogens pose serious challenges to the public health worldwide. Lysin, peptidoglycan hydrolase from phage, is promising alternative to conventional antibiotics because of its high bactericidal activity and low risk of resistance. However, most proteinaceous lysins cannot penetrate the mammalian cell membrane because of size exclusion. Previously, we reported a broad-spectrum chimeric lysin, ClyR, with a cysteine, histidine-dependent amidohydrolase/peptidase catalytic domain from PlyC lysin and an SH-3b cell-wall binding domain from PlySs2 lysin. Herein, we further report that a novel internal cell-penetrating peptide (CPP) is predicted in the junction region of the two constitutive domains of ClyR, mediated by which ClyR can be internalized by epithelial cells through caveolin-dependent endocytosis to target intracellular pathogens. Residues K153, P154, R169, and R188 of the internal CPP were found to be essential for ClyR-mediated internalization and intracellular killing. RNA-seq analysis further showed that there are minor differences in transcript and metabolic profiles from epithelial cells exposed to 100 µg/ml ClyR for 24 h. Taken together, our findings demonstrate a novel mechanism of internalization by ClyR, providing new insights into the rational designing of the next-generation lysins to target both extracellular and intracellular pathogens.


Assuntos
Bacteriófagos , Peptídeos Penetradores de Células , Animais , Antibacterianos , N-Acetil-Muramil-L-Alanina Amidase , Peptídeo Hidrolases
3.
J Cell Mol Med ; 25(4): 1911-1926, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33350586

RESUMO

Accumulating evidence has suggested that extracellular vesicles (EVs) play a crucial role in lung cancer treatment. Thus, we aimed to investigate the modulatory role of bone marrow mesenchymal stem cell (BMSC)-EV-derived let-7i and their molecular mechanism in lung cancer progression. Microarray-based analysis was applied to predict lung cancer-related miRNAs and their downstream genes. RT-qPCR and Western blot analyses were conducted to determine Let-7i, lysine demethylase 3A (KDM3A), doublecortin-like kinase 1 (DCLK1) and FXYD domain-containing ion transport regulator 3 (FXYD3) expressions, after which dual-luciferase reporter gene assay and ChIP assay were used to identify the relationship among them. After loss- and gain-of-function assays, the effects of let-7i, KDM3A, DCLK1 and FXYD3 on the biological characteristics of lung cancer cells were assessed. Finally, tumour growth in nude mice was assessed by xenograft tumours in nude mice. Bioinformatics analysis screened out the let-7i and its downstream gene, that is KDM3A. The findings showed the presence of a high expression of KDM3A and DCLK1 and reduced expression of let-7i and FXYD3 in lung cancer. KDM3A elevated DCLK1 by removing the methylation of H3K9me2. Moreover, DCLK1 suppressed the FXYD3 expression. BMSC-EV-derived let-7i resulted in the down-regulation of KDM3A expression and reversed its promoting role in lung cancer development. Consistently, in vivo experiments in nude mice also confirmed that tumour growth was suppressed by the BMSC-EV-derived let-7i. In conclusion, our findings demonstrated that the BMSC-EV-derived let-7i possesses an inhibitory role in lung cancer progression through the KDM3A/DCLK1/FXYD3 axis, suggesting a new molecular target for lung cancer treatment.


Assuntos
Vesículas Extracelulares/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , Transdução de Sinais , Adulto , Idoso , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Quinases Semelhantes a Duplacortina , Feminino , Xenoenxertos , Histonas/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Histona Desmetilases com o Domínio Jumonji , Masculino , Proteínas de Membrana , Camundongos , Pessoa de Meia-Idade , Modelos Biológicos , Proteínas de Neoplasias , Proteínas Serina-Treonina Quinases
4.
Front Genet ; 12: 807628, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35140744

RESUMO

Objective: This research probed into the molecular mechanisms of long non-coding RNA (lncRNA) VPS9D1 Antisense RNA 1 (VPS9D1-AS1) in lung adenocarcinoma (LUAD). Methods: lncRNA expression level was evaluated bioinformatically, and its downstream miRNA/mRNA regulatory axis was predicted by bioinformatics methods as well. qRT-PCR was used to measure VPS9D1-AS1, miRNA-30a-5p, and kinesin family member 11 (KIF11) expression. Western blot was performed to measure KIF11 protein expression. Proliferation, migration, and invasion of LUAD cells were all observed by cell biological function experiments. Dual-luciferase assay detected binding between miRNA-30a-5p and VPS9D1-AS1 or KIF11, respectively. RIP experiment detected interaction between VPS9D1-AS1 and miRNA-30a-5p. Results: VPS9D1-AS1 and KIF11 were increased in LUAD, whereas miRNA-30a-5p was decreased. VPS9D1-AS1 promoted the malignant progression of LUAD cells and could sponge miRNA-30a-5p. MiRNA-30a-5p could restore the impact of VPS9D1-AS1 on LUAD cells. KIF11 was a target downstream of miRNA-30a-5p. VPS9D1-AS1 could upregulate KIF11 expression through competitively sponging miRNA-30a-5p, and KIF11 could restore the impact of miRNA-30a-5p on LUAD cells. Conclusion: VPS9D1-AS1 could foster malignant progression of LUAD via regulating miRNA-30a-5p/KIF11 axis, suggesting that VPS9D1-AS1 is key to regulating the malignant progression of LUAD.

5.
Gastroenterol Res Pract ; 2020: 1958573, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32565778

RESUMO

BACKGROUND AND AIMS: To investigate the clinical effect of preservation or nonpreservation of the left colic artery (LCA) in total mesorectal excision (TME) under laparoscopy. METHODS: The words, like "rectal cancer," "left colonic artery," and "laparoscopy," were used as the retrieval terms, and the keyword retrieval method was adopted. The retrieval period was set as from January 1, 2013, to June 1, 2018. We searched databases including PubMed, Web of Science, and China National Knowledge Infrastructure (CNKI) to collect randomized and controlled trials which compared the effect of preservation or nonpreservation of the LCA in TME under laparoscopy. Two researchers independently carried out literature screening, data extraction, and literature quality evaluation; Review Manager 5.3 was used for the meta-analysis. RESULTS: Seven studies including 1467 cases were identified for the meta-analysis. As showed by the meta-analysis, compared with the LCA nonpreservation group, the LCA preservation group had significantly reduced incidence of anastomotic leakage (OR = 0.44, CI = [0.30, 0.65], P < 0.0001) and postoperative urinary and sexual dysfunction (OR = 0.26, CI = [0.09, 0.78], P = 0.02) and significantly shorter time for intestinal function recovery (WMD = -0.26, CI = [-0.41, -0.11], P = 0.0008). There were no significant differences between the two groups in the duration of surgery, blood loss, number of dissected lymph nodes, or postoperative hospital stay. CONCLUSIONS: From the results, the LCA preservation group seems to achieve comparable success with acceptable safety outcomes. Therefore, this surgical method can be recommended in the clinical practice.

6.
Appl Microbiol Biotechnol ; 104(4): 1609-1619, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31900556

RESUMO

The emergence of antibiotic-resistant beta-hemolytic Streptococcus agalactiae strains poses increasing threat to human beings globally. As an attempt to create a novel lysin with improved activity against S. agalactiae, a chimeric lysin, ClyV, was constructed by fusing the enzymatically active domain (EAD) from PlyGBS lysin (GBS180) and the cell wall binding domain (CBD) from PlyV12 lysin (V12CBD). Plate lysis assay combined with lytic kinetic analysis demonstrated that ClyV has improved activity than its parental enzymatic domain GBS180 against multiple streptococci. Biochemical characterization showed that ClyV is active from pH 7 to 10, with the optimum pH of 9, and is stable under NaCl concentration of < 500 mM. In a S. agalactiae infection model, a single intraperitoneally administration of 0.1 mg/mouse of ClyV protected 100% mice, while it was observed that ~ 29% survive in group that received a single dose of 0.1 mg/mouse of GBS180. Moreover, a high dose of 0.8 mg/mouse ClyV did not show any adverse effects to the health or survival rate of the mice. Considering the robust bactericidal activity and good safety profile of ClyV, it represents a potential candidate for the treatment of S. agalactiae infections.


Assuntos
Antibacterianos/farmacologia , Enzimas/farmacologia , Proteínas Recombinantes de Fusão/farmacologia , Infecções Estreptocócicas/tratamento farmacológico , Streptococcus agalactiae/efeitos dos fármacos , Animais , Enzimas/biossíntese , Enzimas/genética , Feminino , Injeções Intraperitoneais , Cinética , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes de Fusão/biossíntese , Infecções Estreptocócicas/microbiologia
7.
Environ Microbiol ; 22(3): 1125-1140, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31858668

RESUMO

Bacillus thuringiensis is the most widely used eco-friendly biopesticide, containing two primary determinants of biocontrol, endospore and insecticidal crystal proteins (ICPs). The 2-methylcitrate cycle is a widespread carbon metabolic pathway playing a crucial role in channelling propionyl-CoA, but with poorly understood metabolic regulatory mechanisms. Here, we dissect the transcriptional regulation of the 2-methylcitrate cycle operon prpCDB and report its unprecedented role in controlling the sporulation process of B. thuringiensis. We found that the transcriptional activity of the prp operon encoding the three critical enzymes PrpC, PrpD, and PrpB in the 2-methylcitrate cycle was negatively regulated by the two global transcription factors CcpA and AbrB, while positively regulated by the LysR family regulator CcpC, which jointly account for the fact that the 2-methylcitrate cycle is specifically and highly active in the stationary phase of growth. We also found that the prpD mutant accumulated 2-methylcitrate, the intermediate metabolite of the 2-methylcitrate cycle, which delayed and inhibited sporulation at the early stage. Thus, our results not only revealed sophisticated transcriptional regulatory mechanisms for the metabolic 2-methylcitrate cycle but also identified 2-methylcitrate as a novel regulator of sporulation in B. thuringiensis.


Assuntos
Bacillus thuringiensis/crescimento & desenvolvimento , Bacillus thuringiensis/genética , Proteínas de Bactérias/genética , Citratos/metabolismo , Regulação Bacteriana da Expressão Gênica/genética , Hidroliases/genética , Esporos Bacterianos/genética , Acil Coenzima A/metabolismo , Bacillus thuringiensis/enzimologia , Proteínas de Bactérias/metabolismo , Redes e Vias Metabólicas/genética , Óperon/genética , Esporos Bacterianos/crescimento & desenvolvimento , Fatores de Transcrição/genética
8.
Artigo em Inglês | MEDLINE | ID: mdl-31767724

RESUMO

Streptococcus pneumoniae is a leading human pathogen uniquely characterized by choline moieties on the bacterial surface. Our previous work reported a pneumococcus-specific chimeric lysin, ClyJ, which combines the CHAP (cysteine, histidine-dependent amidohydrolase/peptidase) enzymatically active domain (EAD) from the PlyC lysin and the cell wall binding domain (CBD) from the phage SPSL1 lysin, which imparts choline binding specificity. Here, we demonstrate that the lytic activity of ClyJ can be further improved by editing the linker sequence adjoining the EAD and CBD. Keeping the net charge of the linker constant, we constructed three ClyJ variants containing different lengths of linker sequence. Circular dichroism showed that linker editing has only minor effects on the folding of the EAD and CBD. However, thermodynamic examination combined with biochemical analysis demonstrated that one variant, ClyJ-3, with the shortest linker, displayed improved thermal stability and bactericidal activity, as well as reduced cytotoxicity. In a pneumococcal mouse infection model, ClyJ-3 showed significant protective efficacy compared to that of the ClyJ parental lysin or the Cpl-1 lysin, with 100% survival at a single ClyJ-3 intraperitoneal dose of 100 µg/mouse. Moreover, a ClyJ-3 dose of 2 µg/mouse had the same efficacy as a ClyJ dose of 40 µg/mouse, suggesting a 20-fold improvement in vivo Taking these results together, the present study not only describes a promising pneumococcal lysin with improved potency, i.e., ClyJ-3, but also implies for the first time that the linker sequence plays an important role in determining the activity of a chimeric lysin, providing insight for future lysin engineering studies.


Assuntos
Antituberculosos/farmacologia , Edição de Genes/métodos , Streptococcus pneumoniae/enzimologia , Streptococcus pneumoniae/genética , Animais , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Domínio Catalítico/genética , Parede Celular/metabolismo , Colina/metabolismo , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Engenharia de Proteínas , Fagos de Streptococcus , Relação Estrutura-Atividade
9.
Front Psychol ; 10: 1888, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31507480

RESUMO

Purpose: The primary aim of the present study is to examine the effect of 8-week mind-body exercise intervention combining aerobic jogging and mindfulness-based yoga on implicit emotion regulation ability. The secondary aim is to explore the specific potential pathways by which the mind-body exercise intervention fosters implicit emotion regulation. This may help us to understand how the key components of exercise intervention contribute to emotional benefits. Methods: Sixty participants were randomly allocated to one of two parallel groups: (1) the intervention group (n = 29) and (2) the waitlist control group (n = 31). Participants were asked to fill out scales measuring mindfulness and instructed to complete an emotion regulation task to assess implicit emotion regulation ability as well as the PWC 170 Test to evaluate aerobic fitness before and after the intervention. Results: The results of the two-way repeated ANOVA revealed that 8 weeks of intervention improved implicit emotion regulation, mindfulness, and aerobic fitness levels. Path analysis showed that only improved aerobic fitness mediated the intervention effect on implicit emotion regulation ability, controlling for change in negative affect. Notably, the relationship between the effects on implicit emotion regulation ability and aerobic fitness was moderated by improved mindfulness. Conclusion: Eight weeks of mind-body exercise intervention improves implicit emotion regulation ability. The aerobic fitness may be an essential pathway which mediates the efficacy on implicit emotion regulation ability. Furthermore, different components, such as aerobic fitness and mindfulness, may interactively contribute to such emotional benefits.

10.
Artigo em Inglês | MEDLINE | ID: mdl-30642930

RESUMO

Streptococcus pneumoniae is one of the leading pathogens that cause a variety of mucosal and invasive infections. With the increased emergence of multidrug-resistant S. pneumoniae, new antimicrobials with mechanisms of action different from conventional antibiotics are urgently needed. In this study, we identified a putative lysin (gp20) encoded by the Streptococcus phage SPSL1 using the LytA autolysin as a template. Molecular dissection of gp20 revealed a binding domain (GPB) containing choline-binding repeats (CBRs) that are high specificity for S. pneumoniae By fusing GPB to the CHAP (cysteine, histidine-dependent amidohydrolase/peptidase) catalytic domain of the PlyC lysin, we constructed a novel chimeric lysin, ClyJ, with improved activity to the pneumococcal Cpl-1 lysin. No resistance was observed in S. pneumoniae strains after exposure to incrementally doubling concentrations of ClyJ for 8 continuous days in vitro In a mouse bacteremia model using penicillin G as a control, a single intraperitoneal injection of ClyJ improved the survival rate of lethal S. pneumoniae-infected mice in a dose-dependent manner. Given its high lytic activity and safety profile, ClyJ may represent a promising alternative to combat pneumococcal infections.


Assuntos
Amidoidrolases/metabolismo , Bacteriófagos/enzimologia , Endopeptidases/metabolismo , Peptídeo Hidrolases/metabolismo , Infecções Pneumocócicas/tratamento farmacológico , Streptococcus pneumoniae/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Domínio Catalítico , Modelos Animais de Doenças , Endopeptidases/farmacologia , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Infecções Pneumocócicas/prevenção & controle
11.
Artigo em Inglês | MEDLINE | ID: mdl-30397070

RESUMO

The determination of antibiotic potency against bacterial strains by assessment of their minimum inhibitory concentration normally uses a standardized broth microdilution assay procedure developed more than 50 years ago. However, certain antibiotics require modified assay conditions in order to observe optimal activity. For example, daptomycin requires medium supplemented with Ca2+, and the lipoglycopeptides dalbavancin and oritavancin require Tween 80 to be added to the growth medium to prevent the depletion of free drug via adsorption to the plastic microplate. In this report, we examine systematically the effects of several different plate types on microdilution broth MIC values for a set of antibiotics against Gram-positive and Gram-negative bacteria, both in medium alone and in medium supplemented with the commonly used additives Tween 80, lysed horse blood, and 50% human serum. We observed very significant differences in measured MICs (up to 100-fold) for some lipophilic antibiotics, such as the Gram-positive lipoglycopeptide dalbavancin and the Gram-negative lipopeptide polymyxins, and found that nonspecific binding plates can replace the need for surfactant additives. Microtiter plate types and any additives should be specified when reporting broth dilution MIC values, as results can vary dramatically for some classes of antibiotics.


Assuntos
Meios de Cultura/química , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana/instrumentação , Aminoglicosídeos/química , Aminoglicosídeos/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Cálcio/farmacologia , Ciprofloxacina/química , Ciprofloxacina/farmacologia , Colistina/química , Colistina/farmacologia , Meios de Cultura/farmacologia , Depsipeptídeos/química , Depsipeptídeos/farmacologia , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/metabolismo , Análise Fatorial , Lipoglicopeptídeos/química , Lipoglicopeptídeos/farmacologia , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Staphylococcus aureus Resistente à Meticilina/metabolismo , Oxacilina/química , Oxacilina/farmacologia , Penicilina G/química , Penicilina G/farmacologia , Plásticos/química , Polimixina B/química , Polimixina B/farmacologia , Polissorbatos/farmacologia , Rifampina/química , Rifampina/farmacologia , Teicoplanina/análogos & derivados , Teicoplanina/química , Teicoplanina/farmacologia , Trimetoprima/química , Trimetoprima/farmacologia , Vancomicina/química , Vancomicina/farmacologia
12.
Chinese Journal of School Health ; (12): 542-545, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-818817

RESUMO

Objective@#To investigate the effect of exercise intervention on sleep quality of female college students with anxiety, and to further explore the mediating effect of negative emotions in this association.@*Methods@#Seventy female college students were randomly divided into experimental group (34 patients) and control group(36 patients). The experimental group received eight-week aerobic exercise and yoga training. The control group received no training. Sleep Quality Scale, Negative Emotion Scale and Anxiety Self-rating Scale were used to assess the level of sleep and negative emotion before and after exercise intervention.@*Results@#After exercise intervention, sleep quality (4.31±1.26), anxiety (36.41±7.32) and negative emotion (2.37±0.50) in the experimental group significantly improved(P<0.01), no similar changes were found in the control group(P<0.05). By examining the mediating effects, negative emotions played a partial mediating role in the association between exercise and sleep quality(t=6.77, P<0.01).@*Conclusion@#Exercise intervention significantly improved the quality of sleep and negative emotion among female college students with anxiety. Negative emotions play a partial role in the positive effect of exercise on sleep quality.

13.
Pancreatology ; 18(8): 935-944, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30316690

RESUMO

The transient receptor potential TRPM8 ion channel is required for cellular proliferation in pancreatic epithelia and adenocarcinoma. To elucidate the mechanism that mediates the function of TRPM8, we examined its role in the proliferation and invasion of pancreatic cancer (PC) cells. TRPM8 expression increased in both the PC tissues and cell lines; a high TRPM8 expression was correlated with poorer prognosis in patients with PC. In PC cell lines, PACN-1 and BxPC-3, Ca2+ influxes could be evoked by TRPM8; the sensitivity of PC cells to gemcitabine was increased, while the proliferation and invasion of PC cells were suppressed after RNA interference-mediated silencing of TRPM8. The mechanism of TRPM8 in gemcitabine-based chemotherapy was then investigated. The expression and activity of multidrug resistance-associated proteins, P-gp, MRP-2, LRP, was significantly reduced in response to TRPM8 silence. Moreover, TRPM8 knockdown significantly increased hENT1 protein levels and the ratio of Bax/Bcl-2 while decreased the protein levels of RRM1. Thus, TRPM8 is required for PC cell proliferation and invasion and was closely related to the gemcitabine sensitivity of PC. The modulation of TRPM8 expression may help improve treatment response of PC by combining with traditional chemotherapy.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Desoxicitidina/análogos & derivados , Inativação Gênica , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/terapia , Canais de Cátion TRPM/genética , Adulto , Idoso , Cálcio/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Terapia Combinada , Desoxicitidina/uso terapêutico , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteína 2 Associada à Farmacorresistência Múltipla , Invasividade Neoplásica , Neoplasias Pancreáticas/patologia , Prognóstico , RNA Interferente Pequeno/uso terapêutico , Canais de Cátion TRPM/antagonistas & inibidores , Gencitabina
14.
Viruses ; 10(6)2018 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-29844267

RESUMO

Enterococcus faecalis is a commensal opportunistic pathogen found in the intestine, mouth, and vaginal tract of humans. As an invasive pathogen in the oral cavity, E. faecalis is one of the leading causes of periapical endodontic lesions. However, due to the strong biofilm-forming capacity and tolerance of E. faecalis to conventional antibiotics and treatments, limited therapeutic options are available. In the present study, we investigated the activity of ClyR, a chimeric lysin with extended streptococcal lytic spectrum, against planktonic and sessile E. faecalis cells in vitro and in an ex vivo dental model. Our results showed that ClyR has robust and rapid lytic activity against multiple E. faecalis strains, killing >90% planktonic cells within 1 min at a concentration of 50 µg/mL. The biochemical experiments combined with microscopy analysis revealed that ClyR degrades E. faecalis biofilm with high efficacy in a dose-dependent manner, reducing the survival rate to 90% viable bacteria within biofilms at a low dose of 50 µg/mL, which is much better than ampicillin and similar to calcium hydroxide, the extensively used routine intracanal medicament in the treatment of endodontics and dental traumatology. The robust activity of ClyR against both planktonic and sessile E. faecalis suggests the potential of ClyR in treating endodontic infections caused by E. faecalis.


Assuntos
Antibacterianos/farmacologia , Cavidade Pulpar/microbiologia , Enterococcus faecalis/efeitos dos fármacos , Enzimas/farmacologia , Ampicilina/farmacologia , Biofilmes/efeitos dos fármacos , Hidróxido de Cálcio/farmacologia , Cavidade Pulpar/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana
15.
Nat Commun ; 9(1): 22, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29295973

RESUMO

The public health threat posed by a looming 'post-antibiotic' era necessitates new approaches to antibiotic discovery. Drug development has typically avoided exploitation of membrane-binding properties, in contrast to nature's control of biological pathways via modulation of membrane-associated proteins and membrane lipid composition. Here, we describe the rejuvenation of the glycopeptide antibiotic vancomycin via selective targeting of bacterial membranes. Peptide libraries based on positively charged electrostatic effector sequences are ligated to N-terminal lipophilic membrane-insertive elements and then conjugated to vancomycin. These modified lipoglycopeptides, the 'vancapticins', possess enhanced membrane affinity and activity against methicillin-resistant Staphylococcus aureus (MRSA) and other Gram-positive bacteria, and retain activity against glycopeptide-resistant strains. Optimised antibiotics show in vivo efficacy in multiple models of bacterial infection. This membrane-targeting strategy has potential to 'revitalise' antibiotics that have lost effectiveness against recalcitrant bacteria, or enhance the activity of other intravenous-administered drugs that target membrane-associated receptors.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Daptomicina/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Vancomicina/farmacologia , Animais , Antibacterianos/metabolismo , Antibacterianos/farmacocinética , Bactérias/classificação , Sobrevivência Celular/efeitos dos fármacos , Glicopeptídeos/metabolismo , Células HEK293 , Células Hep G2 , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
16.
Front Neurosci ; 12: 942, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30618571

RESUMO

In this work, we systematically analyzed the effects of various nodal definitions, as determined by a multi-granularity whole-brain segmentation scheme, upon the topological architecture of the human brain functional network using the resting-state functional magnetic resonance imaging data of 19 healthy, young subjects. A number of functional networks were created with their nodes defined according to two types of anatomical definitions (Type I and Type II) each of which consists of five granularity levels of whole brain segmentations with each level linked through ontology-based, hierarchical, structural relationships. Topological properties were computed for each network and then compared across levels within the same segmentation type as well as between Type I and Type II. Certain network architecture patterns were observed in our study: (1) As the granularity changes, the absolute values of each node's nodal degree and nodal betweenness change accordingly but the relative values within a single network do not change considerably; (2) The average nodal degree is generally affected by the sparsity level of the network whereas the other topological properties are more specifically affected by the nodal definitions; (3) Within the same ontology relationship type, as the granularity decreases, the network becomes more efficient at information propagation; (4) The small-worldness that we observe is an intrinsic property of the brain's resting-state functional network, independent of the ontology type and the granularity level. Furthermore, we validated the aforementioned conclusions and measured the reproducibility of this multi-granularity network analysis pipeline using another dataset of 49 healthy young subjects that had been scanned twice.

17.
Neuroscience ; 366: 70-83, 2017 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-29037598

RESUMO

In this paper, by utilizing surface diffeomorphic deformations, we constructed and analyzed subcortical shape morphometric networks in 210 healthy control (HC) subjects and 175 subjects with Alzheimer's disease (AD), aiming to identify AD-induced abnormalities in the subcortical shape network. We quantitatively analyzed pertinent network attributes of the entire network and each node. Further to this, hierarchical analyses were performed; group comparisons were conducted at the structure level first and then the sub-region level. The bilateral amygdalae, hippocampi, as well as the thalamus were all divided into multiple functionally distinct sub-regions. From the structure level analysis, we found significant HC-vs-AD group differences in the average local efficiency and average global efficiency. In addition, the local nodal efficiencies between the right thalamus and all three of the right hippocampus, right amygdala, and left thalamus, as well as that between the left amygdala and left hippocampus, decreased significantly in AD. According to the sub-regional network analyses, we observed significant AD-induced local efficiency decreases between different sub-regions within the right hippocampus itself and between the subiculum of the right hippocampus and the sub-region of the right thalamus connecting to the temporal lobe, indicating a degradation of circuit between the hippocampus, thalamus, and temporal lobe. Statistical comparisons were performed using 40,000 non-parametric permutation tests, with false discovery rate correction employed for multiple comparison correction.


Assuntos
Doença de Alzheimer/patologia , Encéfalo/patologia , Vias Neurais/patologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/patologia , Encéfalo/diagnóstico por imagem , Feminino , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Tálamo/patologia
18.
Int J Ophthalmol ; 10(3): 406-412, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28393032

RESUMO

AIM: To evaluate the morphological changes in anterior segment in Chinese patients with uveal effusion (UE) after the attack of acute primary angle-closure (APAC) using ultrasound biomicroscopy (UBM), and to assess the clinical course and prognosis of the disease. METHODS: In a retrospective case series, 26 eyes in 26 consecutive patients diagnosed with UE after the treatment of intraocular pressure (IOP)-lowering medication for the attack of APAC were enrolled. The unaffected fellow eyes served as controls. The morphological changes were observed by ultrasonography, slit lamp microscopy and gonioscopy. UBM was used to assess the degree and extent of effusion based on the analysis of parameters associated with UE. RESULTS: The mean IOP was 9.2 (SD 2.1) mm Hg at the diagnosis of UE after IOP-lowering medication, while 14.1 (SD, 2.6) mm Hg in the fellow eyes (P=0.000). The anterior chamber depth (ACD) (P=0.000), angle opening distance at 500 µm (AOD500) (P<0.01) and anterior chamber angle (ACA) (P<0.05) were decreased significantly, while ciliary body thickness (CBT) (P<0.05) increased significantly in UE eyes. UE grade analysis showed 7 eyes in grade 1, 9 eyes in grade 2, and 10 eyes in grade 3. Quadrant scores were performed of 4 eyes in 1 quadrant, 3 eyes in 3 quadrants, and 19 eyes in 4 quadrants. There was the positive correlation between grade and quadrant score (r=0.644, P=0.000). The effusion on all eyes were recovered after medication, which mean IOP was 13.9 (SD, 2.8) mm Hg. CONCLUSION: UE is a frequent complication in Chinese patients after the attack of APAC, partially associated with hypotony. The severity of UE is correlation with height of effusion, extent of detachment, and shallower ACD.

19.
Wei Sheng Wu Xue Bao ; 57(1): 121-30, 2017 Jan 04.
Artigo em Chinês | MEDLINE | ID: mdl-29746766

RESUMO

Objective: To study the regulation of sporulation controlled by two-component system (TCS) YvcPQ. Methods: ß-galactosidase experiment was used to verify the regulation of YvcP on kapD expression; bacterial one-hybrid assay, EMSA and RT-qPCR were applied to study the regulation of AbrB on yvcPQ expression; markerless gene deletion coupled with spore count was used to reveal the influence of yvcPQ and kapD expressions on sporulation. Results: transcriptional regulator AbrB up-regulated the expression of yvcPQ; YvcP promoted the expression of kapD to inhibit sporulation. Conclusion: AbrB up-regulated the transcription of yvcPQ operon, then the increased YvcP strengthened the transcriptional acitivation of sporulation inhibitor gene kapD, and subsequently inhibited sporulation.


Assuntos
Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Bacillus thuringiensis/genética , Proteínas de Bactérias/genética , Óperon , Esporos Bacterianos/genética , Esporos Bacterianos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica
20.
Biopolymers ; 96(2): 147-57, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20564028

RESUMO

Citropin 1.1, maculatin 1.1, and caerin 1.1 are short antibacterial cationic peptides from the skin glands of the Australian tree frog Litoria species. Several analogues have been synthesized to give a better insight into the relationship between the structure of the peptides and their antibacterial and haemolytic activity. Binding studies using a surface plasmon resonance (SPR) biosensor together with a vesicle-capture sensor chip have been used to investigate selectivity of the peptides and their analogues for 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol (DMPG) and 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) vesicles, as well as for vesicles made from lipid extracts from Escherichia coli and bovine brain. Data obtained for membrane selectivity using natural lipid extracts show better correlation with minimum inhibitory concentration (MIC) values against Gram-positive bacteria and haemolytic activity than that obtained using synthetic DMPG and DMPC. Electron microscopy and membrane leakage studies using Gram-positive bacteria gave further insight into the membrane disruption properties of the peptides. For maculatin 1.1, it was found that the central proline residue, which is responsible for a bend in the alpha-helical structure, is essential not only for the antibacterial activity but also for binding, and perturbation of membranes. The caerin analogues showed only small variations in their MIC values and membrane binding. In contrast, for citropin 1.1, the analogue replacing the aspartate with a lysine showed the lowest MIC against Gram-positive bacteria and best membrane binding to E. coli lipid extracts, coinciding with an increased hydrophobic moment of the peptide. These data give further insight into these antimicrobial natural products, toward the development and evaluation of these and other analogues as potential antibiotics.


Assuntos
Proteínas de Anfíbios/química , Peptídeos Catiônicos Antimicrobianos/química , Membranas Artificiais , Proteínas de Anfíbios/farmacologia , Animais , Peptídeos Catiônicos Antimicrobianos/farmacologia , Química Encefálica , Bovinos , Escherichia coli/química , Bactérias Gram-Positivas/crescimento & desenvolvimento , Humanos , Ressonância de Plasmônio de Superfície
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