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1.
Front Endocrinol (Lausanne) ; 15: 1397512, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38745951

RESUMO

Background: The Oxidative Balance Score (OBS) is commonly used to assess oxidative stress and provides a comprehensive evaluation of dietary and lifestyle-related exposures. However, there is limited research on the association between OBS and colorectal cancer (CRC), its subsites, and complications. The objective of this study was to assess the relationship between OBS and the risk of CRC, its subsites, and common complications in a large prospective cohort study. Methods: We included data from 175,808 participants in the UK Biobank data sample repository from 2006 to 2010. We evaluated OBS using a scoring system based on 22 dietary and lifestyle factors. Multiple adjustments, including multivariate Cox proportional hazard regression, gender stratification, subgroup analysis, and sensitivity analysis, were performed to fully explore the relationship between OBS and CRC, its subsites, and complications. The mediation analysis was conducted to investigate whether serum albumin, uric acid, and neutrophil levels mediate the relationship between OBS and CRC. Results: After adjusting for potential confounding factors, a significant negative correlation was found between OBS and the risk of CRC and its subsites (proximal colon cancer, distal colon cancer, and rectal cancer). This correlation was particularly pronounced in male CRC patients. Serum albumin, uric acid, and neutrophil count, which are biomarkers, were found to have a significant mediating effect between OBS and CRC. Conclusion: Our study suggests that higher exposure to antioxidants assessed through OBS (diet and lifestyle rich in antioxidants) may decrease the occurrence of CRC and its subsites.


Assuntos
Neoplasias Colorretais , Estresse Oxidativo , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/prevenção & controle , Neoplasias Colorretais/sangue , Estudos Prospectivos , Incidência , Idoso , Fatores de Risco , Estilo de Vida , Adulto , Dieta , Ácido Úrico/sangue , Reino Unido/epidemiologia , Seguimentos
2.
J Clin Nurs ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38572996

RESUMO

BACKGROUND: Older hospitalised patients have low levels of physical activity and multiple impairing factors. AIMS: To systematically evaluate the perceived barriers to physical activity among older patients during hospitalisation, and provide reference for future intervention programs. DESIGN: Following ENTREQ, do a systematic evaluation and synthesis of qualitative investigations. METHODS: An exhaustive exploration was conducted across the CNKI, Wanfang Database, VIP Database, China Biomedical Literature Database, PubMed, Embase, Cochrane Library and Web of Science from their inception until August, 2023 to identify qualitative research on obstacles to physical activity among older hospital patients. The quality of the literature was evaluated using the Joanna Briggs Institute's critical appraisal tool for qualitative research. Meta-synthesis method was used to integrate the results. RESULTS: In total, 8 literatures were included, 43 themes were extracted, and analogous research results were amalgamated to generate 10 categories and 3 syntheses: individual level, interpersonal influencing factors and hospital environment and resources level. CONCLUSION: Older inpatients are faced with multiple barriers to physical activity. Medical staff should pay attention to changes in physical activity during hospitalisation, identify barriers to physical activity in older inpatients and provide references for promoting physical activity programs for the older. NO PATIENT OR PUBLIC CONTRIBUTION: This study is a meta-synthesis and does not require relevant contributions from patients or the public. WHAT IS ALREADY KNOWN: Older patients are at low physical activity levels during hospitalisation. Older inpatients are faced with multiple barriers to physical activity. WHAT THIS PAPER ADDS: Factors of physical activity impairment in hospitalised older patients should be considered in the context of health status, psychological factors, motivation and social support. Disease-induced psychological fallout has a greater impact on physical activity in the older.

3.
Front Immunol ; 15: 1359540, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469291

RESUMO

Background and aims: Inflammatory bowel disease (IBD), mainly categorized into Crohn's disease (CD) and ulcerative colitis (UC), is a chronic relapsing gastrointestinal disorder that significantly impairs patients' quality of life. IBD patients often experience comorbidities such as anxiety and depression, and the underlying mechanisms and treatment strategies remain areas of investigation. Methods: We conducted a Mendelian randomization(MR) analysis utilizing brain image derived phenotypes (IDP) from the UK Biobank database to investigate the causal relationships between IBD and alterations in brain structural morphology and connectivity of neural tracts. This study aimed to identify biological evidence linking IBD to psychiatric disorders such as anxiety and depression. Results: Specifically, the volume of grey matter in the Left Frontal Orbital Cortex exhibited a negative association with the onset of Crohn's disease (odds ratio (OR) [95% confidence interval (CI)]: 0.315[0.180~0.551], adjusted P=0.001), while the volume of the superior frontal cortex in the right hemisphere showed a positive correlation with the development of Ulcerative colitis (OR [95% CI]: 2.285[1.793~2.911], adjusted P<0.001), and the volume of lateral occipital cortex in the left hemisphere demonstrated a positive relationship with Crohn's disease onset (OR [95% CI]: 1.709[1.671~1.747], adjusted P<0.001). In the context of reverse causality, the onset of UC or CD has led to alterations in imaging derived phenotypes associated with five disorders (anxiety, depression, schizophrenia, bipolar disorder, pain) and three functions (memory, emotion, language). Conclusion: Our study has demonstrated a causal relationship between IBD and IDPs. IDPs may serve as potential biomarkers for the progression of IBD and as predictive intermediaries for the development of neurological diseases in IBD patients.


Assuntos
Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Humanos , Qualidade de Vida , Encéfalo/diagnóstico por imagem , Biomarcadores , Fenótipo , Neuroimagem
4.
Med Sci Monit ; 30: e942687, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38439525

RESUMO

BACKGROUND Sleep disorders are a common disease faced by people today and can lead to fatigue, lack of concentration, impaired memory, and even death. In recent years, the development of brain stimulation techniques has provided a new perspective for the treatment of sleep disorders. However, there is a lack of bibliometric analyses related to sleep disorders and brain stimulation techniques. Therefore, this study analyzed the application status and trend of brain stimulation technology in sleep disorder research. MATERIAL AND METHODS Articles and reviews published between 1999 and 2023 were retrieved from the Web of Science. CiteSpace was used to visually analyze the publications, countries, institutions, journals, authors, references, and keywords. RESULTS A total of 459 publications were obtained. The number of studies was shown to be on a general upward trend. The country with the largest number of publications was the United States; UDICE-French Research Universities had the highest number of publications; Neurology had the highest citation frequency; 90% of the top 10 references cited were from Journal Citation Reports Q1; Brigo was the author with the highest number of publications; and the most frequent keywords were "transcranial magnetic stimulation", "deep brain stimulation", and "Parkinson disease". CONCLUSIONS Our study used CiteSpace software to analyze 459 studies published since 1999 on brain stimulation techniques for the treatment of sleep disorders, revealing research trends and the current state of the field. Our results will help researchers to understand the existing research quickly and provide direction for future research.


Assuntos
Bibliometria , Transtornos do Sono-Vigília , Humanos , Fadiga , Transtornos do Sono-Vigília/terapia , Tecnologia , Encéfalo
5.
Artigo em Inglês | MEDLINE | ID: mdl-38437147

RESUMO

Using functional connectivity (FC) or effective connectivity (EC) alone cannot effectively delineate brain networks based on functional magnetic resonance imaging (fMRI) data, limiting the understanding of the mechanism of tinnitus and its treatment. Investigating brain FC is a foundational step in exploring EC. This study proposed a functionally guided EC (FGEC) method based on reinforcement learning (FGECRL) to enhance the precision of identifying EC between distinct brain regions. An actor-critic framework with an encoder-decoder model was adopted as the actor network. The encoder utilizes a transformer model; the decoder employs a bidirectional long short-term memory network with attention. An FGEC network was constructed for the enrolled participants per fMRI scan, including 65 patients with tinnitus and 28 control participants healthy at the enrollment time. After 6 months of sound therapy for tinnitus and prospective follow-up, fMRI data were acquired again and retrospectively categorized into an effective group (EG) and an ineffective group (IG) according to the treatment effect. Compared with FC and EC, the FGECRL method demonstrated better accuracy in discriminating between different groups, highlighting the advantage of FGECRL in identifying brain network features. For the FGEC network of the EG and IG per state (before and after treatment) and healthy controls, effective therapy is characterized by a similar pattern of FGEC network between patients with tinnitus after treatment and healthy controls. Deactivated information output in the motor network, somatosensory network, and medioventral occipital cortex may biologically indicate effective treatment. The maintenance of decreased EC in the primary auditory cortex may represent a failure of sound therapy, further supporting the Bayesian inference theory for tinnitus perception. The FGEC network can provide direct evidence for the mechanism of sound therapy in patients with tinnitus with distinct outcomes.


Assuntos
Mapeamento Encefálico , Zumbido , Humanos , Mapeamento Encefálico/métodos , Estudos Retrospectivos , Zumbido/terapia , Teorema de Bayes , Estudos Prospectivos , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
6.
J Clin Nurs ; 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38108248

RESUMO

AIM: To analyse the risk factors and incidence of falls in geriatric outpatients in a university hospital ward in Hangzhou, China. METHODS: From May 2020 to August 2022, 1712 geriatric outpatients in a university hospital ward in Hangzhou, China, were screened using a socio-demographic questionnaire (e.g. gender, age, living arrangement, etc.) and assessment scales. The correlation between each factor and falls was preliminarily analysed by chi-squared tests. Finally, binary logistic regression analysis was conducted to further analyse the risk factors of falls. The STROBE checklist was used in reporting this study. RESULTS: Of the 1712 geriatric outpatients recruited, 1626 participants (60-79 and ≥ 80 years old) with complete questionnaire and assessment data were included. The occurrence of falls for those in the 60-79 age group was 8.4%, and for those in the ≥80 age group it was 13.4%. Age (p = .007), use of a walking assistance device (p < .001), the Stay Independent Brochure Questionnaire (SIB) (OR = 7.751, 95% CI = 5.089-11.806, p < .001), living arrangement (p = .004), timed up and go test (TUGT) (p = .007) and three diseases or above (OR = 2.496, 95% CI = 1.358-11.4.586, p = .003) reached statistical significance. CONCLUSIONS: Older people have a high incidence of falls. In this study, age, disease history, SIB scores (≥4 points), living arrangement, TUGT and walking assistance device increased the probability of falls in older Chinese adults. Personalised interventions should be carried out according to the specific situation of older people to effectively reduce their incidence of falls and improve their quality of life. RELEVANCE TO CLINICAL PRACTICE: The basic characteristics and fall risk factors of the older can help nurses identify fall risk, and early intervention by caregivers can reduce fall-related injuries, which has practical significance for promoting healthy aging. PATIENT OR PUBLIC CONTRIBUTION: The subjects of this study were older patients ≥60 years old, and the demographic characteristics and fall-related information of patients were obtained by questionnaire. The team worked closely with a team of experts in the field of health care. Some researchers collect data and rewrite them, while other researchers analyse the information and write a paper. All authors read and approved the final manuscript.

8.
Cerebellum ; 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993636

RESUMO

Ataxia-ocular apraxia 2 (AOA2) is a rare neurodegenerative autosomal recessive disorder with no effective treatment. In this study, we present the case of a patient diagnosed with AOA2, who experienced walking instability and uncoordinated movement. The patient underwent transcranial alternating current stimulation (tACS) treatment for 4 weeks with follow-up after 1 month. The effectiveness of the treatment was evaluated using the International Cooperative Ataxia Rating Scale (ICARS), the Scale for the Assessment and Rating of Ataxia (SARA), the 9-Hole Peg Test (9HPT), and functional near-infrared spectroscopy (fNIRS). Following treatment, the patient's ataxia symptoms showed significant improvement and continued to be alleviated during the follow-up period, suggesting a lasting effect of tACS treatment. Our findings from this case study provide compelling evidence for the potential of tACS as a treatment option for AOA2.

9.
Brain Commun ; 5(5): fcad261, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37869577

RESUMO

We determined the structural and functional alterations in the insula and its subregions in patients with idiopathic tinnitus in order to identify the neural changes involved in the progression from recent onset to chronic tinnitus. We recruited 24 recent-onset tinnitus patients, 32 chronic tinnitus patients and 36 healthy controls. We measured the grey matter volume and fractional amplitude of low-frequency fluctuation of the insula and its subregions and the functional connectivity within the insula and between the insula and the rest of the brain. Relationships between MRI and clinical characteristics were estimated using partial correlation analysis. Both recent-onset and chronic tinnitus patients showed decreased fractional amplitude of low-frequency fluctuation in the insula and its subregions, but only chronic tinnitus patients showed bilateral grey matter atrophy in the ventral anterior insula. Abnormal functional connectivity was detected in recent-onset and chronic tinnitus patients relative to the healthy controls, but functional connectivity differences between recent-onset and chronic tinnitus patients were found in only the auditory-related cortex, frontal cortex and limbic system. Functional alterations (fractional amplitude of low-frequency fluctuation and functional connectivity of the left ventral anterior insula), but not structural changes, were correlated with clinical severity. Bilateral grey matter atrophy in the ventral anterior insula decreased regional activities in the left ventral anterior insula and left posterior insula, and abnormal functional connectivity of the insula subregions with auditory and non-auditory areas were implicated in the progression from recent onset to chronic tinnitus. This suggests that tinnitus generation and development occur in a dynamic manner and involve aberrant multi-structural and functional (regional brain activity and abnormal functional connectivity) reorganization of the insula.

10.
Med Sci Monit ; 29: e941486, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37661601

RESUMO

BACKGROUND Inspiratory muscle training (IMT) aims to train inspiratory muscles based mainly on the diaphragm by applying a load resistance during the inspiratory process. Many papers related to IMT have been published in various journals; however, no articles objectively and directly present the development trends and research hotspots of IMT. Therefore, this study used CiteSpace to visually analyze recent IMT-related publications to provide valuable information for future IMT-related studies. MATERIAL AND METHODS CiteSpace was applied to analyze the IMT-related publications by countries, institutions, journals, authors, references, and keywords. RESULTS We included 504 papers. The number of IMT-related publications trended upward between 2009 and 2022. Leuven had the highest number of publications by an institution. The American Journal of Respiratory and Critical Care Medicine was the most frequently co-cited journal. Half of the top 10 references cited were from Journal Citation Reports (JCR) Q1 and half were about the application of IMT in chronic obstructive pulmonary disorder. Gosselink was the author with the highest number of publications and Aldrich was the author with the highest co-citation frequency. The preponderance of studies on the surgical population and postoperative pulmonary complications reflects potential application of IMT in enhanced recovery after surgery. CONCLUSIONS This study provides scholars with important information related to IMT research. It analyzes IMT research trends and status, which can help researchers identify primary topics in the field and find ways to explore new research directions to promote the application of IMT in clinical practice and the cooperation of IMT-related disciplines.


Assuntos
Diafragma , Instalações de Saúde , Humanos , Modalidades de Fisioterapia , Complicações Pós-Operatórias , Período Pós-Operatório
11.
CNS Neurosci Ther ; 29(12): 4070-4081, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37392024

RESUMO

AIMS: This study systematically investigated structural and functional alterations in the thalamus and its subregions using multimodal magnetic resonance imaging (MRI) and examined its clinical relevance in tinnitus patients with different outcomes after sound therapy (narrowband noise). METHODS: In total, 60 patients with persistent tinnitus and 57 healthy controls (HCs) were recruited. Based on treatment efficacy, 28 patients were categorized into the effective group and 32 into the ineffective group. Five MRI measurements of the thalamus and its seven subregions, including gray matter volume, fractional anisotropy, fractional amplitude of low-frequency fluctuation, and functional connectivity (FC), were obtained for each participant and compared between the groups. RESULTS: Patients in both the groups exhibited widespread functional and diffusion abnormalities in the whole thalamus and several subregions, with more obvious changes observed in the effective group. All tinnitus patients had abnormal FC compared with the HCs; FC differences between the two patient groups were only observed in the striatal network, auditory-related cortex, and the core area of the limbic system. We combined the multimodal quantitative thalamic alterations and used it as an imaging indicator to evaluate prognosis before sound therapy and achieved a sensitivity of 71.9% and a specificity of 85.7%. CONCLUSION: Similar patterns of thalamic alterations were identified in tinnitus patients with different outcomes, with more obvious changes observed in the effective group. Our findings support the tinnitus generation hypothesis of frontostriatal gating system dysfunction. A combination of multimodal quantitative thalamic properties may be used as indicators to predict tinnitus prognosis before sound therapy.


Assuntos
Zumbido , Humanos , Zumbido/diagnóstico por imagem , Zumbido/terapia , Zumbido/patologia , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Sistema Límbico/patologia , Tálamo/diagnóstico por imagem
12.
Polymers (Basel) ; 15(14)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37514508

RESUMO

Structural damping composites exhibit considerable potential in aerospace and other fields due to their excellent damping and vibration reduction performance, as well as their structural carrying capacity. However, conventional structural damping composite materials generally do not combine excellent mechanical and damping properties at the same time, which makes it difficult for them to meet the practical demand in engineering. In this paper, polyetherimide (PEI) non-woven fabric interlayer materials loaded with quantified polydopamine (PDA) and carboxylated multi-walled carbon nanotubes (MWCNTs-COOH) were used to prepare carbon fiber-reinforced bismaleimide composites through the co-curing process. The mechanical and damping properties of the composites were systematically studied. The results demonstrate that PEI non-woven fabric interlayers loaded with PDA and MWCNTs-COOH can synchronously improve the mechanical and damping properties of the co-cured composites. The incorporation of carbon nanotubes and polydopamine during the co-curing process synergistically improves the flexural strength, flexural modulus, interlaminar shear strength, and impact fracture toughness of the composites. Most importantly, damping properties show an increase of 45.0% in the loss factor of the co-cured composites. Moreover, the reinforcement mechanism was investigated using the optical microscopy and scanning electron microscopy, which indicated that the PEI interlayers loaded with carbon nanotubes and polydopamine form a rich resin area between the layers of the composites.

13.
J Zhejiang Univ Sci B ; 24(6): 539-543, 2023 Jun 15.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37309045

RESUMO

Epstein-Barr virus (EBV), a double-stranded DNA virus with an envelope, is a ubiquitous pathogen that is prevalent in humans, although most people who contract it do not develop symptoms (Kerr, 2019). While the primary cells EBV attacks are epithelial cells and B lymphocytes, its target range expands to a variety of cell types in immunodeficient hosts. Serological change occurs in 90% of infected patients. Therefore, immunoglobulin M (IgM) and IgG, serologically reactive to viral capsid antigens, are reliable biomarkers for the detection of acute and chronic EBV infections (Cohen, 2000). Symptoms of EBV infection vary according to age and immune status. Young patients with primary infection may present with infectious mononucleosis; there is a typical triad of symptoms including fever, angina, and lymphadenectasis (Houen and Trier, 2021). In immunocompromised patients, response after EBV infection may be atypical, with unexplained fever. The nucleic acid of EBV can be detected to confirm whether high-risk patients are infected (Smets et al., 2000). EBV is also associated with the occurrence of certain tumors (such as lymphoma and nasopharyngeal carcinoma) because it transforms host cells (Shannon-Lowe et al., 2017; Tsao et al., 2017).


Assuntos
Infecções por Vírus Epstein-Barr , Viroses , Humanos , Traqueia , Herpesvirus Humano 4 , Febre , Granuloma
14.
Exp Ther Med ; 25(6): 241, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37153898

RESUMO

Chronic pain is the primary symptom of osteoarthritis affecting a patient's quality of life. Neuroinflammation and oxidative stress in the spinal cord contribute to arthritic pain and represent ideal targets for pain management. In the present study, a model of arthritis was established by intra-articular injection of complete Freund's adjuvant (CFA) into the left knee joint in mice. After CFA inducement, knee width and pain hypersensitivity in the mice were increased, motor disability was impaired, spinal inflammatory reaction was induced, spinal astrocytes were activated, antioxidant responses were decreased, and glycogen synthase kinase 3ß (GSK-3ß) activity was inhibited. To explore the potential therapeutic options for arthritic pain, lycorine was intraperitoneally injected for 3 days in the CFA mice. Lycorine treatment significantly reduced mechanical pain sensitivity, suppressed spontaneous pain, and recovered motor coordination in the CFA-induced mice. Additionally, in the spinal cord, lycorine treatment decreased the inflammatory score, reduced NOD-like receptor protein 3 inflammasome (NLRP3) activity and IL-1ß expression, suppressed astrocytic activation, downregulated NF-κB levels, increased nuclear factor erythroid 2-related factor 2 expression and superoxide dismutase activity. Furthermore, lycorine was shown to bind to GSK-3ß through three electrovalent bonds, to inhibit GSK-3ß activity. In summary, lycorine treatment inhibited GSK-3ß activity, suppressed NLRP3 inflammasome activation, increased the antioxidant response, reduced spinal inflammation, and relieved arthritic pain.

15.
Polymers (Basel) ; 15(8)2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37111984

RESUMO

Metal-organic frameworks (MOFs) have been previously shown as an emerging modified class of epoxy resin. In this work, we report a simple strategy for preventing zeolitic imidazolate framework (ZIF-8) nanoparticles from agglomerating in epoxy resin (EP). Branched polyethylenimine grafted ZIF-8 in ionic liquid (BPEI-ZIF-8) nanofluid with good dispersion was prepared successfully using an ionic liquid as both the dispersant and curing agent. Results indicated that the thermogravimetric curve of the composite material had no noticeable change with increasing BPEI-ZIF-8/IL content. The glass transition temperature (Tg) of the epoxy composite was reduced with the addition of BPEI-ZIF-8/IL. The addition of 2 wt% BPEI-ZIF-8/IL into EP effectively improved the flexural strength to about 21.7%, and the inclusion of 0.5 wt% of BPEI-ZIF-8/IL EP composites increased the impact strength by about 83% compared to pure EP. The effect of adding BPEI-ZIF-8/IL on the Tg of epoxy resin was explored, and its toughening mechanism was analyzed in combination with SEM images showing fractures in the EP composites. Moreover, the damping and dielectric properties of the composites were improved by adding BPEI-ZIF-8/IL.

16.
Small ; 19(34): e2301797, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37093211

RESUMO

Recent studies have found that the existence of oxygen around the active sites may be essential for efficient electrochemical CO2 -to-CO conversion. Hence, this work proposes the modulation of oxygen coordination and investigates the as-induced catalytic behavior in CO2 RR. It designs and synthesizes conjugated phthalocyanine frameworks catalysts (CPF-Co) with abundant CoN4 centers as an active source, and subsequently modifies the electronic structure of CPF-Co by introducing graphene oxide (GO) with oxygen-rich functional groups. A systematic study reveals that the axial coordination between oxygen and the catalytic sites could form an optimized O-CoN4 structure to break the electron distribution symmetry of Co, thus reducing the energy barrier to the activation of CO2 to COOH*. Meanwhile, by adjusting the content of oxygen, the proper supports can also facilitate the charge transfer efficiency between the matrix layer and the catalytic sites. The optimized CPF-Co@LGO exhibits a high TOF value (2.81 s-1 ), CO selectivity (97.6%) as well as stability (24 h) at 21 mA cm-2 current density. This work reveals the modulation of oxygen during CO2 RR and provides a novel strategy for the design of efficient electrocatalysts, which may inspire new exploration and principles for CO2 RR.

17.
Sci Total Environ ; 881: 163424, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37054788

RESUMO

The impacts of nitrogen (N) availability on soil organic carbon (SOC) decomposition were often explored based on N enrichment (N+) experiments. However, many natural and anthropogenic processes often reduce soil N availability. There is no direct evidence about how decreased N availability (N-) affects SOC decomposition, and the mechanisms of microbe-driven SOC decomposition in response to N availability remain unclear. Here, we used ion-exchange membranes to simulate N-. Soil samples from four temperate grassland sites, ranging from non-degradation to extreme degradation, were incubated with the N- and N+ treatments. We found that the total cumulative carbon (C) release was promoted by the N- treatment (8.60 to 87.30 mg C/g Cinital) but was inhibited by the N+ treatment (-129.81 to -16.49 mg C/g Cinital), regardless of the degradation status. N- dramatically increased recalcitrant C decomposition by increasing soil pH at all grassland sites; while did not affect or even decreased labile C decomposition by significantly increasing microbial C use efficiency and soil microbial biomass N. Interestingly, the effects of N- and N+ on SOC decomposition was asymmetric; with increased grassland degradation, the SOC decomposition was more sensitive to N- than to N+. Our results provide direct evidence for the different effects and mechanisms of N- on SOC decomposition and should be considered in soil process models to better predict the response of the nutrient cycle to global changes.

18.
Artigo em Inglês | MEDLINE | ID: mdl-37022456

RESUMO

Tinnitus is associated with abnormal functional connectivity of multiple regions of the brain. However, previous analytic methods have disregarded information on the direction of functional connectivity, leading to only a moderate efficacy of pretreatment planning. We hypothesized that the pattern of directional functional connectivity can provide key information on treatment outcomes. Sixty-four participants were enrolled in this study: eighteen patients with tinnitus were categorized into the effective group, twenty-two patients into the ineffective group, and twenty-four healthy participants into the healthy control group. We acquired resting-state functional magnetic resonance images prior to sound therapy and constructed an effective connectivity network of the three groups using an artificial bee colony algorithm and transfer entropy. The key feature of patients with tinnitus was the significantly increased signal output of the sensory network, including the auditory, visual, and somatosensory networks, and parts of the motor network. This provided critical insights into the gain theory of tinnitus development. The altered pattern of functional information orchestration, represented by a higher degree of hypervigilance-driven attention and enhanced multisensory integration, may explain poor clinical outcomes. The activated gating function of the thalamus is one of the key factors for a good prognosis in tinnitus treatment. We developed a novel method for analyzing effective connectivity, facilitating an understanding of the tinnitus mechanism and treatment outcome expectation based on the direction of information flow.

19.
mSystems ; 8(1): e0095422, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36541763

RESUMO

The disproportionation of inorganic sulfur compounds could be widespread in natural habitats, and microorganisms could produce energy to support primary productivity through this catabolism. However, the microorganisms that carry this process out and the catabolic pathways at work remain relatively unstudied. Here, we investigated the bacterial diversity involved in sulfur disproportionation in hydrothermal plumes from Carlsberg Ridge in the northwestern Indian Ocean by enrichment cultures. A bacterial community analysis revealed that bacteria of the genera Sulfurimonas and Sulfurovum, belonging to the phylum Campylobacterota and previously having been characterized as chemolithoautotrophic sulfur oxidizers, were the most dominant members in six enrichment cultures. Subsequent bacterial isolation and physiological studies confirmed that five Sulfurimonas and Sulfurovum isolates could disproportionate thiosulfate and elemental sulfur. The ability to disproportionate sulfur was also demonstrated in several strains of Sulfurimonas and Sulfurovum that were isolated from hydrothermal vents or other natural environments. Dialysis membrane experiments showed that S0 disproportionation did not require the direct contact of cells with bulk sulfur. A comparative genomic analysis showed that Campylobacterota strains did not contain some genes of the Dsr and rDSR pathways (aprAB, dsrAB, dsrC, dsrMKJOP, and qmoABC) that are involved in sulfur disproportionation in some other taxa, suggesting the existence of an unrevealed catabolic pathway for sulfur disproportionation. These findings provide evidence for the catabolic versatility of these Campylobacterota genera, which are widely distributed in chemosynthetic environments, and expand our knowledge of the microbial taxa involved in this reaction of the biogeochemical sulfur cycle in hydrothermal vent environments. IMPORTANCE The phylum Campylobacterota, notably represented by the genera Sulfurimonas and Sulfurovum, is ubiquitous and predominant in deep-sea hydrothermal systems. It is well-known to be the major chemolithoautotrophic sulfur-oxidizing group in these habitats. Herein, we show that the mesophilic predominant chemolithoautotrophs of the genera Sulfurimonas and Sulfurovum could grow via sulfur disproportionation to gain energy. This is the first report of the chemolithoautotrophic disproportionation of thiosulfate and elemental sulfur within the genera Sulfurimonas and Sulfurovum, and this comes in addition to their already known role in the chemolithoautotrophic oxidation of sulfur compounds. Sulfur disproportionation via chemolithoautotrophic Campylobacterota may represent a previously unrecognized primary production process in hydrothermal vent ecosystems.


Assuntos
Compostos de Enxofre , Tiossulfatos , Compostos de Enxofre/metabolismo , Tiossulfatos/metabolismo , Ecossistema , Água do Mar/microbiologia , Filogenia , Diálise Renal , Enxofre/metabolismo , Bactérias/genética
20.
Plant Dis ; 107(3): 809-819, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35949187

RESUMO

Powdery mildew is a key airborne foliar disease of barley in southeastern and southwestern China. Barley varieties usually partially or wholly lose resistance to the pathogen Blumeria graminis (DC.) f. sp. hordei 3 to 5 years after release due to the frequent acquirements of new virulences in the pathogen population. However, no B. graminis f. sp. hordei virulence detection has been carried out in the recent decade and, thus, no information is available on the present virulence components and major pathotypes in epidemic regions. Twenty-one near-isogenic lines of Pallas were selected to detect B. graminis f. sp. hordei virulence variation, with 97 pathotypes identified from the isolates collected from 2015 to 2019. The virulence complexities ranged from 1 to 12, with 1.5 isolates on average assigned per pathotype, suggesting a natural trait of high pathotype diversity and low virulence complexity in the Chinese B. graminis f. sp. hordei populations. Eleven high-virulence pathotypes were detected in the traditional barley-growing regions in Yunnan and Zhejiang. Six virulent pathotypes to resistance gene mlo-5 were detected only in the two traditional epidemic regions, with a virulence frequency (VF) of 4.8% (7 of 147). Compared with the results from a decade ago, VFs for resistance alleles Mla3, mlo-5, Mla6 + Mla14, Mla7 + Mlk, Mlg + MlCP, and Mla13 + MlRu3 + MlaRu4 increased from 0 to 0.7 to 25.8%. Isolates from Yunnan and Zhejiang had similar virulence profiles, which differed from those identified in Tibet. In addition, genetic diversities differed in the isolate groups collected from Tibet, Yunnan, and Zhejiang.


Assuntos
Ascomicetos , Virulência/genética , China , Ascomicetos/genética , Variação Genética
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