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1.
Artigo em Inglês | MEDLINE | ID: mdl-39422841

RESUMO

The association between leukocyte telomere length (LTL) alteration and major adverse cardiovascular events (MACE) or mortality in patients with hypertension is still unclear. 20,034 patients with essential hypertension were enrolled from UK biobank. Multivariable COX regression models were performed to assess the association. LTL was shorter in hypertensive patients with MACE compared to those without MACE. Hypertensive patients in the lowest LTL quartile were at higher risk to develop MACE (adjusted HR 1.15 [95% CI 1.02-1.29], vs top LTL quartile, p-trend = 0.03). Similarly, shorter LTL was related with increased mortality (adjusted HR 1.18[95% CI 1.06-1.3], lowest vs top LTL quartile, p-trend < 0.001). This investigation demonstrated that shorter LTL is associated with increased risk of MACE or mortality in patients with essential hypertension, which indicates that LTL may be a potential predictor of prognosis or underlying therapeutic target for hypertension.

2.
PLoS One ; 19(10): e0306696, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39418285

RESUMO

Digital technologies are a significant additional powerhouse for corporate internationalization and competitiveness. The existing research has not effectively distinguished the breadth and depth of internationalization, and there are also inadequate context considerations of how much digital technology applications influence enterprise internationalization. To bridge this gap, this paper has selected 203 valid questionnaires from manufacturing enterprises in Zhejiang Province, China, then elaborates and constructs a theoretical model based on existing studies, and using multiple linear regression analysis, finally to empirically assess and further explain the mechanisms of digital technologies' influence on corporate internationalization. The results reveal that utilizing digital technologies has positive influence on both internationalization breadth and depth. Moreover, centralizing decision power negatively moderates the relationship between enterprises' digital applications and their internationalization breadth (or depth), while internationalization experience has opposite influence, with these two factors jointly moderating such relationship. Finally, this research can contribute to better understanding of leveraging digital technologies to upgrade corporate internationalization and provides reasonable theoretical insights for enhancing deeper and more diversified enterprise internationalization.


Assuntos
Tecnologia Digital , Internacionalidade , China , Humanos , Inquéritos e Questionários , Tomada de Decisões
3.
Chem Sci ; 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39397827

RESUMO

Lithium (Li) plating, triggered by fast charging and low temperature, will cause performance degradation and safety concerns for lithium-ion batteries (LIBs). However, strategically limited and controlled Li deposition might be advantageous for enhancing energy density. The detailed mechanism and regulation for performance improvement are yet to be fully explored. This study meticulously modulates the overlithiation capacity to regulate Li plating and probes its effects on the stability of high-capacity silicon/graphite (Si/Gr) electrodes through consecutive cycling and over the calendar aging period. The Si/Gr electrode (20 wt% Si) with a 20% overlithiation degree exhibits enhanced reversible capacity in comparison to the pristine Si/Gr electrode. This improvement is attributed to precision-controlled Li deposition, the increased electrochemical utilization of Si and Gr above 0 V, and the additional intercalation/alloying reactions below 0 V, which decelerate the progression of capacity degradation and significantly boost the electrochemical performance of Si/Gr electrodes. Moreover, this tailored Si/Gr electrode with a 20% overlithiation degree attenuates the deterioration associated with calendar aging. This research not only elucidates the intricate interplay and mechanisms of Li plating on Si/Gr electrodes during overlithiation but also presents a new understanding and approach to advance the performance of LIBs and extend their service lifespan.

4.
J. pediatr. (Rio J.) ; J. pediatr. (Rio J.);100(4): 413-421, July-Aug. 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1564745

RESUMO

Abstract Objective: To examine the mental health status and related factors in children and adolescents, and to assess age groups and sexes differences in factors influencing mental health. Methods: This cross-sectional study was performed on Chinese children aged 6-18 years from November 2021 to January 2022. Mental health difficulties were accessed by the Strengths and Difficulties Questionnaire. Multivariate logistic regression was used to analyze factors associated with mental health status. Multiple linear regression was used to evaluate factors associated with the scores of the Strengths and Difficulties Questionnaire. Results: The prevalence of mental health difficulties was 12.98% (n =1348). Age (OR, 0.909, [95%CI, 0.830-0.996]), sex (OR, 1.424, [95%CI, 1.033-1.963]) and screen time on weekdays ("≥2" h/d vs "< 1" h/d: OR, 2.001, [95%CI, 1.300-3.080]) were related factors for mental health difficulties. For children (year ≤ 12), the strongest related factor for mental health difficulties was screen time on weekdays ("≥ 2" h/d vs "< 1" h/d: OR, 1.821 [95%CI, 1.203-2.755]). The risk of mental health difficulties in females with ≥ 2 h/d screen time on weekends was 3.420 times higher than those with < 1 h/d (OR, 3.420, [95%CI, 1.923-6.081]). Conclusion: The prevalence of mental health difficulties among children and adolescents was relatively high. The lower age, female sex and excessive screen time were associated with a higher risk of mental health difficulties. The factors influencing mental health varied by different age groups and sexes. Thus, specific measures for different age groups and sexes should be adopted to mitigate the impact.

5.
bioRxiv ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38915556

RESUMO

Borrelia (or Borreliella) burgdorferi, the causative agent of Lyme disease, is a motile and invasive zoonotic pathogen, adept at navigating between its arthropod vector and mammalian host. While motility and chemotaxis are well established as essential for its enzootic cycle, the function of methyl-accepting chemotaxis proteins (MCPs) in the infectious cycle of B. burgdorferi remains unclear. In this study, we demonstrate that MCP5, one of the most abundant MCPs in B. burgdorferi, is differentially expressed in response to environmental signals as well as at different stages of the pathogen's enzootic cycle. Specifically, the expression of mcp5 is regulated by the Hk1-Rrp1 and Rrp2-RpoN-RpoS pathways, which are critical for the spirochete's colonization of the tick vector and mammalian host, respectively. Infection experiments with an mcp5 mutant revealed that spirochetes lacking MCP5 could not establish infections in either C3H/HeN mice or Severe Combined Immunodeficiency (SCID) mice, which are defective in adaptive immunity, indicating the essential role of MCP5 in mammalian infection. However, the mcp5 mutant could establish infection and disseminate in NOD SCID Gamma (NSG) mice, which are deficient in both adaptive and most innate immune responses, suggesting a crucial role of MCP5 in evading host innate immunity. In the tick vector, the mcp5 mutants survived feeding but failed to transmit to mice, highlighting the importance of MCP5 in transmission. Our findings reveal that MCP5, regulated by the Rrp1 and Rrp2 pathways, is critical for the establishment of infection in mammalian hosts by evading host innate immunity and is important for the transmission of spirochetes from ticks to mammalian hosts, underscoring its potential as a target for intervention strategies.

6.
J Nutr ; 154(10): 3060-3069, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38735573

RESUMO

OBJECTIVE: This study aimed to investigate the association between consumption of ultra-processed foods (UPFs) and leucocyte telomere length (LTL). METHODS: This cross-sectional study utilized data from the UK Biobank, including a total of 64,690 participants. LTL was measured using Q-PCR with natural logarithmic conversion and Z-score normalization. Dietary data were collected through a 24-hour recall questionnaire from 2009 to 2010. UPFs were identified using the Nova food classification and analyzed as either a continuous or categorical variable respectively. Multiple linear regression models were employed to analyze the association between UPF consumption and LTL. RESULTS: The included participants had an average age of 56.26 years, of whom 55.2% were female. After adjusting for sociodemographic, lifestyle-related and anthropometric variables, LTL exhibited a decrease of 0.005 (95% CI: -0.007, -0.002) with one UPF serving/day increase. Compared to participants consuming ≤ 3.5 servings/day, those consuming 3.5 to < 6, 6 to ≤ 8 and > 8 servings/day showed a shortening of LTL by 0.025 (95% CI: -0.047, -0.004), 0.034 (95% CI: -0.055, -0.012) and 0.038 (95% CI: -0.062, -0.015), respectively (P for trend = 0.001). Subgroup analyses by UPF subclasses revealed that consumption of ready-to-eat/heated food (ß = -0.008, 95% CI: -0.014, -0.002), beans and potatoes (ß = -0.024, 95% CI: -0.039, -0.009), animal-based products (ß = -0.011, 95% CI: -0.019, -0.004), artificial sugar (ß = -0.014, 95% CI: -0.025, -0.004), and beverages (ß = -0.005, 95% CI: -0.009, -0.001) showed negative associations with LTL. Conversely, breakfast cereals (ß = 0.020, 95% CI: 0.004, 0.036) and vegetarian alternatives (ß = 0.057, 95% CI: 0.027, 0.086) showed positive correlations with LTL. CONCLUSIONS: Our study found that a higher consumption of total UPFs was associated with a shorter LTL. However, some subclass UPFs may be associated with longer LTL, depending on their nutritional composition.


Assuntos
Bancos de Espécimes Biológicos , Dieta , Leucócitos , Telômero , Humanos , Feminino , Masculino , Estudos Transversais , Pessoa de Meia-Idade , Leucócitos/metabolismo , Reino Unido , Fast Foods , Idoso , Manipulação de Alimentos , Adulto , Alimento Processado , Biobanco do Reino Unido
7.
Medicine (Baltimore) ; 103(15): e37790, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38608058

RESUMO

Twist1 has been identified as a critical gene in tumor, but current study of this gene remains limitative. This study aims to investigate its roles and potential mechanisms across pan-cancer. The study used various databases and computational techniques to analyze twist's RNA expression, clinical data, gene mutations, tumor stemness, tumor microenvironment, immune regulation. Furthermore, the experimental method of fluorescence staining was carried out to identify twist1 expression in various tumor masses. After analyzing the protein-protein interaction of TWIST, enrichment analysis and predictive potential drugs were performed, and molecular docking was conducted to validate. We found that twist1 expression was significantly higher in various types of cancer and associated with tumor stage, grade, and poor prognosis in multiple cancers. Differential expression of twist1 was linked to gene mutation, RNA modifications, and tumor stemness. Additionally, twist1 expression was positively associated with tumor immunoregulation and immune checkpoint. Salinomycin, klugline, isocephaelince, manassantin B, and pimonidazole are predictive potential drugs targeting TWIST1. This study revealed that twist1 plays an important role in tumor, and might be a curial marker in tumor diagnose and prognosis. The study also highlighted twist1 as a promising therapeutic target for cancer treatment and provided a foundation for future research.


Assuntos
Neoplasias , Humanos , Biomarcadores , Simulação de Acoplamento Molecular , Neoplasias/diagnóstico , Neoplasias/genética , Prognóstico , RNA , Microambiente Tumoral
8.
J Pediatr (Rio J) ; 100(4): 413-421, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38642590

RESUMO

OBJECTIVE: To examine the mental health status and related factors in children and adolescents, and to assess age groups and sexes differences in factors influencing mental health. METHODS: This cross-sectional study was performed on Chinese children aged 6-18 years from November 2021 to January 2022. Mental health difficulties were accessed by the Strengths and Difficulties Questionnaire. Multivariate logistic regression was used to analyze factors associated with mental health status. Multiple linear regression was used to evaluate factors associated with the scores of the Strengths and Difficulties Questionnaire. RESULTS: The prevalence of mental health difficulties was 12.98% (n =1348). Age (OR, 0.909, [95%CI, 0.830-0.996]), sex (OR, 1.424, [95%CI, 1.033-1.963]) and screen time on weekdays ("≥2" h/d vs "< 1" h/d: OR, 2.001, [95%CI, 1.300-3.080]) were related factors for mental health difficulties. For children (year ≤ 12), the strongest related factor for mental health difficulties was screen time on weekdays ("≥ 2" h/d vs "< 1" h/d: OR, 1.821 [95%CI, 1.203-2.755]). The risk of mental health difficulties in females with ≥ 2 h/d screen time on weekends was 3.420 times higher than those with < 1 h/d (OR, 3.420, [95%CI, 1.923-6.081]). CONCLUSION: The prevalence of mental health difficulties among children and adolescents was relatively high. The lower age, female sex and excessive screen time were associated with a higher risk of mental health difficulties. The factors influencing mental health varied by different age groups and sexes. Thus, specific measures for different age groups and sexes should be adopted to mitigate the impact.


Assuntos
COVID-19 , Transtornos Mentais , Saúde Mental , Humanos , Adolescente , Estudos Transversais , Criança , Feminino , Masculino , COVID-19/epidemiologia , COVID-19/psicologia , China/epidemiologia , Transtornos Mentais/epidemiologia , Prevalência , Fatores Sexuais , Fatores Etários , Tempo de Tela , Fatores de Risco , Inquéritos e Questionários , Pandemias , População do Leste Asiático
9.
Sleep Med ; 117: 18-24, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38493659

RESUMO

BACKGROUND: The relationships between sleep duration and aging-associated diseases are intricate. Leukocyte telomere length (LTL) is a biomarker of aging, while the association of sleep duration and LTL is unclear. METHODS: The 310,091 study participants from UK Biobank were enrolled in this cross-sectional study. Restricted cubic splines (RCS) analysis was firstly performed to assess the nonlinear relationship between sleep duration and LTL. Sleep duration was then categorized into three groups: <7 h (short sleep duration), 7-8 h (reference group), and >8 h (long sleep duration) and multiple linear regression was applied to analyze the association of short sleep and long sleep duration with LTL. We further performed subgroup analyses stratified by sex, age, chronotype and snoring. RESULTS: RCS showed an inverted J-shaped relationship between sleep duration and LTL. Compared with the reference group, the inverse association of long sleep duration and LTL was statistically significant in fully-adjusted model (P = 0.001). Subgroup analyses showed that this association was more apparent in people over 50 years (51-60 y: P = 0.002; >60 y: P = 0.005), in men (P = 0.022), and in people preferred evening chronotype (P = 0.001). CONCLUSION: Compared with participants sleeping 7-8 h, those sleep longer than 8 h had shorter LTL in middle-aged and young-old adults. The negative association between long sleep duration and LTL was more apparent in older people, in men, and in people preferred evening chronotype.


Assuntos
Duração do Sono , Biobanco do Reino Unido , Pessoa de Meia-Idade , Adulto , Masculino , Humanos , Idoso , Estudos Transversais , Bancos de Espécimes Biológicos , Leucócitos , Telômero
10.
Infect Immun ; 92(3): e0034423, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38376159

RESUMO

As one of the keystone pathogens of periodontitis, the oral bacterium Porphyromonas gingivalis produces an array of virulence factors, including a recently identified sialidase (PG0352). Our previous report involving loss-of-function studies indicated that PG0352 plays an important role in the pathophysiology of P. gingivalis. However, this report had not been corroborated by gain-of-function studies or substantiated in different P. gingivalis strains. To fill these gaps, herein we first confirm the role of PG0352 in cell surface structures (e.g., capsule) and serum resistance using P. gingivalis W83 strain through genetic complementation and then recapitulate these studies using P. gingivalis ATCC33277 strain. We further investigate the role of PG0352 and its counterpart (PGN1608) in ATCC33277 in cell growth, biofilm formation, neutrophil killing, cell invasion, and P. gingivalis-induced inflammation. Our results indicate that PG0352 and PGN1608 are implicated in P. gingivalis cell surface structures, hydrophobicity, biofilm formation, resistance to complement and neutrophil killing, and host immune responses. Possible molecular mechanisms involved are also discussed. In summary, this report underscores the importance of sialidases in the pathophysiology of P. gingivalis and opens an avenue to elucidate their underlying molecular mechanisms.


Assuntos
Periodontite , Porphyromonas gingivalis , Humanos , Virulência , Neuraminidase/genética , Neuraminidase/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Periodontite/microbiologia
11.
PNAS Nexus ; 2(12): pgad349, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38047041

RESUMO

Spirochetes cause Lyme disease, leptospirosis, syphilis, and several other human illnesses. Unlike other bacteria, spirochete flagella are enclosed within the periplasmic space where the filaments distort and push the cell body by the action of the flagellar motors. We previously demonstrated that the oral pathogen Treponema denticola (Td) and Lyme disease pathogen Borreliella burgdorferi (Bb) form covalent lysinoalanine (Lal) cross-links between conserved cysteine and lysine residues of the FlgE protein that composes the flagellar hook. In Td, Lal is unnecessary for hook assembly but is required for motility, presumably due to the stabilizing effect of the cross-link. Herein, we extend these findings to other, representative spirochete species across the phylum. We confirm the presence of Lal cross-linked peptides in recombinant and in vivo-derived samples from Treponema spp., Borreliella spp., Brachyspira spp., and Leptospira spp. As was observed with Td, a mutant strain of Bb unable to form the cross-link has greatly impaired motility. FlgE from Leptospira spp. does not conserve the Lal-forming cysteine residue which is instead substituted by serine. Nevertheless, Leptospira interrogans FlgE also forms Lal, with several different Lal isoforms being detected between Ser-179 and Lys-145, Lys-148, and Lys-166, thereby highlighting species or order-specific differences within the phylum. Our data reveal that the Lal cross-link is a conserved and necessary posttranslational modification across the spirochete phylum and may thus represent an effective target for the development of spirochete-specific antimicrobials.

12.
PLoS Pathog ; 19(11): e1011752, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38011206

RESUMO

As an enzootic pathogen, the Lyme disease bacterium Borrelia burgdorferi possesses multiple copies of chemotaxis proteins, including two chemotaxis histidine kinases (CHK), CheA1 and CheA2. Our previous study showed that CheA2 is a genuine CHK that is required for chemotaxis; however, the role of CheA1 remains mysterious. This report first compares the structural features that differentiate CheA1 and CheA2 and then provides evidence to show that CheA1 is an atypical CHK that controls the virulence of B. burgdorferi through modulating the stability of RpoS, a key transcriptional regulator of the spirochete. First, microscopic analyses using green-fluorescence-protein (GFP) tags reveal that CheA1 has a unique and dynamic cellular localization. Second, loss-of-function studies indicate that CheA1 is not required for chemotaxis in vitro despite sharing a high sequence and structural similarity to its counterparts from other bacteria. Third, mouse infection studies using needle inoculations show that a deletion mutant of CheA1 (cheA1mut) is able to establish systemic infection in immune-deficient mice but fails to do so in immune-competent mice albeit the mutant can survive at the inoculation site for up to 28 days. Tick and mouse infection studies further demonstrate that CheA1 is dispensable for tick colonization and acquisition but essential for tick transmission. Lastly, mechanistic studies combining immunoblotting, protein turnover, mutagenesis, and RNA-seq analyses reveal that depletion of CheA1 affects RpoS stability, leading to reduced expression of several RpoS-regulated virulence factors (i.e., OspC, BBK32, and DbpA), likely due to dysregulated clpX and lon protease expression. Bulk RNA-seq analysis of infected mouse skin tissues further show that cheA1mut fails to elicit mouse tnf-α, il-10, il-1ß, and ccl2 expression, four important cytokines for Lyme disease development and B. burgdorferi transmigration. Collectively, these results reveal a unique role and regulatory mechanism of CheA1 in modulating virulence factor expression and add new insights into understanding the regulatory network of B. burgdorferi.


Assuntos
Borrelia burgdorferi , Doença de Lyme , Carrapatos , Animais , Camundongos , Histidina Quinase/genética , Histidina Quinase/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Virulência , Quimiotaxia , Doença de Lyme/genética , Doença de Lyme/microbiologia , Carrapatos/microbiologia , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Regulação Bacteriana da Expressão Gênica , Fator sigma/genética , Fator sigma/metabolismo
13.
PLoS Pathog ; 19(9): e1011674, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37747935

RESUMO

The complement system is the first line of innate immune defense against microbial infections. To survive in humans and cause infections, bacterial pathogens have developed sophisticated mechanisms to subvert the complement-mediated bactericidal activity. There are reports that sialidases, also known as neuraminidases, are implicated in bacterial complement resistance; however, its underlying molecular mechanism remains elusive. Several complement proteins (e.g., C1q, C4, and C5) and regulators (e.g., factor H and C4bp) are modified by various sialoglycans (glycans with terminal sialic acids), which are essential for their functions. This report provides both functional and structural evidence that bacterial sialidases can disarm the complement system via desialylating key complement proteins and regulators. The oral bacterium Porphyromonas gingivalis, a "keystone" pathogen of periodontitis, produces a dual domain sialidase (PG0352). Biochemical analyses reveal that PG0352 can desialylate human serum and complement factors and thus protect bacteria from serum killing. Structural analyses show that PG0352 contains a N-terminal carbohydrate-binding module (CBM) and a C-terminal sialidase domain that exhibits a canonical six-bladed ß-propeller sialidase fold with each blade composed of 3-4 antiparallel ß-strands. Follow-up functional studies show that PG0352 forms monomers and is active in a broad range of pH. While PG0352 can remove both N-acetylneuraminic acid (Neu5Ac) and N-glycolyl-neuraminic acid (Neu5Gc), it has a higher affinity to Neu5Ac, the most abundant sialic acid in humans. Structural and functional analyses further demonstrate that the CBM binds to carbohydrates and serum glycoproteins. The results shown in this report provide new insights into understanding the role of sialidases in bacterial virulence and open a new avenue to investigate the molecular mechanisms of bacterial complement resistance.


Assuntos
Neuraminidase , Ácidos Siálicos , Humanos , Neuraminidase/metabolismo , Ácidos Siálicos/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Proteínas do Sistema Complemento , Fatores Imunológicos , Porphyromonas gingivalis
14.
bioRxiv ; 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37398457

RESUMO

Spirochete bacteria cause Lyme disease, leptospirosis, syphilis and several other human illnesses. Unlike other bacteria, spirochete flagella are enclosed within the periplasmic space where the filaments distort and push the cell body by action of the flagellar motors. We previously demonstrated that the oral pathogen Treponema denticola (Td) catalyzes the formation of covalent lysinoalanine (Lal) crosslinks between conserved cysteine and lysine residues of the FlgE protein that composes the flagellar hook. Although not necessary for hook assembly, Lal is required for motility of Td, presumably due to the stabilizing effect of the crosslink. Herein, we extend these findings to other, representative spirochete species across the phylum. We confirm the presence of Lal crosslinked peptides in recombinant and in vivo -derived samples from Treponema spp., Borreliella spp., Brachyspira spp., and Leptospira spp.. Like with Td, a mutant strain of the Lyme disease pathogen Borreliella burgdorferi unable to form the crosslink has impaired motility. FlgE from Leptospira spp. does not conserve the Lal-forming cysteine residue which is instead substituted by serine. Nevertheless, Leptospira interrogans also forms Lal, with several different Lal isoforms being detected between Ser-179 and Lys-145, Lys-148, and Lys-166, thereby highlighting species or order-specific differences within the phylum. Our data reveals that the Lal crosslink is a conserved and necessary post-translational modification across the spirochete phylum and may thus represent an effective target for spirochete-specific antimicrobials. Significance Statement: The phylum Spirochaetota contains bacterial pathogens responsible for a variety of diseases, including Lyme disease, syphilis, periodontal disease, and leptospirosis. Motility of these pathogens is a major virulence factor that contributes to infectivity and host colonization. The oral pathogen Treponema denticola produces a post-translational modification (PTM) in the form of a lysinoalanine (Lal) crosslink between neighboring subunits of the flagellar hook protein FlgE. Herein, we demonstrate that representative spirochetes species across the phylum all form Lal in their flagellar hooks. T. denticola and B. burgdorferi cells incapable of forming the crosslink are non-motile, thereby establishing the general role of the Lal PTM in the unusual type of flagellar motility evolved by spirochetes.

15.
J Inflamm Res ; 16: 2595-2606, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37360625

RESUMO

Background: Mounting research indicates that brain-derived neurotrophic factor (BDNF), has great potential to increase neuro-hyperresponsiveness and airway resistance in airway allergic disease. The expression level of BDNF has been found to be notably elevated in lung/nasal lavage (NAL) fluid. However, the expression and position of BDNF in ciliated cells with allergic rhinitis remains unclear. Methods: Nasal mucosal cells were collected from patients with allergic rhinitis (AR) and mice which were performed under different allergen challenge time, then observed the expression and position of BDNF located in ciliated cells through the immunofluorescence staining. Nasal mucosa, serum and NAL fluid were collected also. The expression level of BDNF and IL-4/5/13 were detected by RT-PCR. The expressions of BDNF (in serum and NAL fluid), and total-IgE, ovalbumin sIgE (in serum) were detected by ELISA. Results: We found that MFI of BDNF in AR group's ciliated cells was obviously lower than that in the control group, and a negative correlation was discovered between MFI and VAS score. It can be roughly divided into 5 patterns according to its location in the cytoplasm of ciliated cells. In the mouse model, the expressions of BDNF in serum and NAL fluid increased temporarily after allergen stimulation. The MFI of BDNF in ciliated cells displayed an initial increase followed by a subsequent decrease. Conclusion: Our study shows for the first time that, the expression and localization of BNDF were observed in the human nasal ciliated epithelial cells of allergic rhinitis, and the expression of level was less than the control group under the persistent state of allergy. BDNF expression in ciliated cells was transient increased after allergen stimulation and decreased to normal level after 24h in mouse model of allergic rhinitis. This might be the possible source of the transient increase of BNDF in serum and NAL fluid.

16.
IEEE Trans Nanobioscience ; 22(4): 845-854, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37022021

RESUMO

BACKGROUND: Radiosurgery has been recognized as a reasonable treatment for metastatic brain tumors. Increasing the radiosensitivity and synergistic effects are possible ways to improve the therapeutic efficacy of specific regions of tumors. c-Jun-N-terminal kinase (JNK) signaling regulates H2AX phosphorylation to repair radiation-induced DNA breakage. We previously showed that blocking JNK signaling influenced radiosensitivity in vitro and in an in vivo mouse tumor model. Drugs can be incorporated into nanoparticles to produce a slow-release effect. This study assessed JNK radiosensitivity following the slow release of the JNK inhibitor SP600125 from a poly (DL-lactide-co-glycolide) (LGEsese) block copolymer in a brain tumor model. MATERIALS AND METHODS: A LGEsese block copolymer was synthesized to fabricate SP600125-incorporated nanoparticles by nanoprecipitation and dialysis methods. The chemical structure of the LGEsese block copolymer was confirmed by 1H nuclear magnetic resonance (NMR) spectroscopy. The physicochemical and morphological properties were observed by transmission electron microscopy (TEM) imaging and measured with particle size analyzer. The blood-brain barrier (BBB) permeability to the JNK inhibitor was estimated by BBBflammaTM 440-dye-labeled SP600125. The effects of the JNK inhibitor were investigated using SP600125-incorporated nanoparticles and by optical bioluminescence, magnetic resonance imaging (MRI), and a survival assay in a mouse brain tumor model for Lewis lung cancer (LLC)-Fluc cells. DNA damage was estimated by histone γ H2AX expression and apoptosis was assessed by the immunohistochemical examination of cleaved caspase 3. RESULTS: The SP600125-incorporated nanoparticles of the LGEsese block copolymer were spherical and released SP600125 continuously for 24h. The use of BBBflammaTM 440-dye-labeled SP600125 demonstrated the ability of SP600125 to cross the BBB. The blockade of JNK signaling with SP600125-incorporated nanoparticles significantly delayed mouse brain tumor growth and prolonged mouse survival after radiotherapy. γ H2AX, which mediates DNA repair protein, was reduced and the apoptotic protein cleaved-caspase 3 was increased by the combination of radiation and SP600125-incorporated nanoparticles.


Assuntos
Neoplasias Encefálicas , Carcinoma Pulmonar de Lewis , Nanopartículas , Camundongos , Animais , Carcinoma Pulmonar de Lewis/terapia , Caspase 3/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Apoptose
17.
Laryngoscope ; 133(12): 3292-3298, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37022141

RESUMO

OBJECTIVE: This study aimed to investigate the clinical characteristics of sphenoid sinus fungus ball (SSFB) to help increase the accuracy of diagnosis and efficiency of treatment. METHODS: We retrospectively analyzed the data of 77 patients who were histopathologically diagnosed with SSFB. RESULTS: The mean age of SSFB patients was 52.4 years (range 25-84), and 47 patients (61.0%) were female. Compared to age-matched and sex-matched chronic rhinosinusitis (CRS) patients, headache was more common in SSFB patients (79.2%; p < 0.0001). SSFB patients also had higher prevalence of diabetes than CRS (p = 0.0420). The features of computed tomography (CT) were sphenoid sinus opacification (100%), sclerosis (93.5%), calcification (76.6%), and bone erosion (41.6%). Functional endoscopic sinus surgery (FESS) was the best treatment option, and the trans-ethmoid (n = 64, 83.1%) was the most commonly used approach. No one experienced a recurrence of SSFB in 44 successfully contacted patients. Six months after FESS, 91.0% of patients (40/44) established proper drainage in the sphenoid sinus. The recovery rates for headache and nasal symptoms were 91.7% (33/36) and 77.8% (7/9) respectively. CONCLUSION: SSFB is more prevalent in older women and usually presents as unilateral headache. Diabetes is a potential risk factor for SSFB. CT findings provide evidence for diagnosis and suggestions for surgical approaches. FESS is the optimal treatment for SSFB. After FESS, most patients had good prognosis with no recurrence of SSFB. However, regular endoscopic follow-up is required due to the possibility of the postoperative closure of sphenoid ostium. LEVEL OF EVIDENCE: 3 Laryngoscope, 133:3292-3298, 2023.


Assuntos
Diabetes Mellitus , Sinusite , Humanos , Feminino , Idoso , Adulto , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Masculino , Seio Esfenoidal/diagnóstico por imagem , Seio Esfenoidal/cirurgia , Estudos Retrospectivos , Sinusite/diagnóstico , Sinusite/epidemiologia , Sinusite/cirurgia , Endoscopia , Cefaleia , Doença Crônica , Fungos
18.
Nano Lett ; 23(8): 3369-3376, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37052625

RESUMO

Lithium (Li) metal has attracted great attention as a promising high-capacity anode material for next-generation high-energy-density rechargeable batteries. Nonuniform Li+ transport and uneven Li plating/stripping behavior are two key factors that deteriorate the electrochemical performance. In this work, we propose an interphase acid-base interaction effect that could regulate Li plating/stripping behavior and stabilize the Li metal anode. ZSM-5, a class of zeolites with ordered nanochannels and abundant acid sites, was employed as a functional interface layer to facilitate Li+ transport and mitigate the cell concentration polarization. As a demonstration, a pouch cell with a high-areal-capacity LiNi0.95Co0.02Mn0.03O2 cathode (3.7 mAh cm-2) and a ZSM-5 modified thin lithium anode (50 µm) delivered impressive electrochemical performance, showing 92% capacity retention in 100 cycles (375.7 mAh). This work reveals the effect of acid-base interaction on regulating lithium plating/stripping behaviors, which could be extended to developing other high-performance alkali metal anodes.

19.
Infect Immun ; 91(4): e0000823, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-36939335

RESUMO

The bacterial chemotaxis regulatory circuit mainly consists of coupling protein CheW, sensor histidine kinase CheA, and response regulator CheY. Most bacteria, such as Escherichia coli, have a single gene encoding each of these proteins. Interestingly, the Lyme disease pathogen, Borreliella burgdorferi, has multiple chemotaxis proteins, e.g., two CheA, three CheW, and three CheY proteins. The genes encoding these proteins mainly reside in two operons: cheW2-cheA1-cheB2-cheY2 (A-I) and cheA2-cheW3-cheX-cheY3 (A-II). Previous studies demonstrate that all the genes in A-II are essential for the chemotaxis of B. burgdorferi; however, the role of those genes in A-I remains unknown. This study aimed to fill this gap using the CheW2 gene, the first gene in A-I, as a surrogate. We first mapped the transcription start site of A-I upstream of cheW2 and identified a σ70-like promoter (PW2) and two binding sites (BS1 and BS2) of BosR, an unorthodox Fur/Per homolog. We then demonstrated that BosR binds to PW2 via BS1 and BS2 and that deletion of bosR significantly represses the expression of cheW2 and other genes in A-I, implying that BosR is a positive regulator of A-I. Deletion of cheW2 has no impact on the chemotaxis of B. burgdorferi in vitro but abrogates its ability to evade host adaptive immunity, because the mutant can establish systemic infection only in SCID mice and not in immunocompetent BALB/c mice. This report substantiates the previous proposition that A-I is not implicated in chemotaxis; rather, it may function as a signaling transduction pathway to regulate B. burgdorferi virulence gene expression.


Assuntos
Borrelia burgdorferi , Quimiotaxia , Animais , Camundongos , Quimiotaxia/genética , Virulência , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Camundongos SCID , Borrelia burgdorferi/fisiologia , Escherichia coli/metabolismo , Proteínas Quimiotáticas Aceptoras de Metil/metabolismo
20.
J Bacteriol ; 205(2): e0046322, 2023 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36715541

RESUMO

FlgM, an antagonist of FliA (also known as σ28), inhibits transcription of bacterial class 3 flagellar genes. It does so primarily through binding to free σ28 to prevent it from forming a complex with core RNA polymerase. We recently identified an FliA homolog (FliATd) in the oral spirochete Treponema denticola; however, its antagonist FlgM remained uncharacterized. Herein, we provide several lines of evidence that TDE0201 functions as an antagonist of FliATd. TDE0201 is structurally similar to FlgM proteins, although its sequence is not conserved. Heterologous expression of TDE0201 in Escherichia coli inhibits its flagellin gene expression and motility. Biochemical and mutational analyses demonstrate that TDE0201 binds to FliATd and prevents it from binding to the σ28-dependent promoter. Deletions of flgM genes typically enhance bacterial class 3 flagellar gene expression; however, deletion of TDE0201 has an opposite effect (e.g., the mutant has a reduced level of flagellins). Follow-up studies revealed that deletion of TDE0201 leads to FliATd turnover, which in turn impairs the expression of flagellin genes. Swimming plate, cell tracking, and cryo-electron tomography analyses further disclosed that deletion of TDE0201 impairs spirochete motility and alters flagellar number and polarity: i.e., instead of having bipolar flagella, the mutant has flagella only at one end of cells. Collectively, these results indicate that TDE0201 is a FlgM homolog but acts differently from its counterparts in other bacteria. IMPORTANCE Spirochetes are a group of bacteria that cause several human diseases. A unique aspect of spirochetes is that they have bipolar periplasmic flagella (PFs), which bestow on the spirochetes a unique spiral shape and distinct swimming behaviors. While the structure and function of PFs have been extensively studied in spirochetes, the molecular mechanism that regulates the PFs' morphogenesis and assembly is poorly understood. In this report, FlgM, an anti-σ28 factor, is identified and functionally characterized in the oral spirochete Treponema denticola. Our results show that FlgM regulates the number and polarity of PFs via a unique mechanism. Identification of FliA and FlgM in T. denticola sets a benchmark to investigate their roles in other spirochetes.


Assuntos
Proteínas de Bactérias , Flagelina , Treponema denticola , Proteínas de Bactérias/genética , Escherichia coli/genética , Flagelos/metabolismo , Flagelina/genética , Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Regiões Promotoras Genéticas , Fator sigma/metabolismo , Treponema denticola/genética
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