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1.
Gastrointest Endosc ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38583543

RESUMO

BACKGROUND AND AIMS: Endobiliary radiofrequency ablation (RFA) is an emerging endoscopic palliative adjunctive therapy used for the local treatment of unresectable malignant biliary obstruction (MBO). However, irregular ablation ranges caused by insufficient electrode-to-bile duct contact pose a significant obstacle. We investigated the feasibility of a self-expandable stent (SES)-based electrode with a customized RFA generator in the porcine liver and common bile duct (CBD). METHODS: An SES-RFA system with polarity switching was developed to perform endobiliary RFA. The ablation ranges of 20 ablation protocols were evaluated to validate the feasibility of the newly developed RFA system in the porcine liver. Nine of 20 ablation protocols were selected for evaluation in the porcine CBD with cholangiography, endoscopy, and histologic and immunohistochemical analysis. RESULTS: The SES-RFA system with polarity switching was successfully constructed and demonstrated high accuracy and reproducibility. The ablation area was clearly identified between the 2 SESs. The ablation ranges and degree of mucosal damage, including terminal deoxynucleotidyl transferase-mediated dUTP nick and labeling-positive and heat shock protein 70-positive depositions, increased proportionally with ablation protocols in the porcine liver and CBD (all P < .05). Ablation length and depth linearly increased with ablation protocols from 8.74 ± .25 to 31.25 ± .67 mm and 1.61 ± .09 to 11.94 ± .44 mm, respectively. CONCLUSIONS: The SES-RFA system with polarity switching between electrodes provided an even circumferential area of ablation and enhanced ablation depth between the electrodes. This novel endobiliary RFA system is a promising modality for local ablation in patients with unresectable MBO.

2.
Dev Med Child Neurol ; 66(8): 1096-1105, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38303153

RESUMO

AIM: We compared three different intensities of robot-assisted gait training (RAGT) for achieving favourable outcomes in children with cerebral palsy (CP). METHOD: This study was conducted using a randomized controlled, single-blind design. Thirty children (19 males and 11 females; mean age 6 years 1 month, SD 2 years) with CP classified in Gross Motor Function Classification System levels II and III were assigned to three different RAGT intensity groups: high-intensity (fastest walking speed and lowest body weight support [BWS]), low-intensity (slowest speed and highest BWS), and comfortable intensity (intermediate speed and intermediate BWS). The RAGT intervention was performed three times a week for 6 weeks. Outcome measures included the 88-item Gross Motor Function Measure, stability index, spatiotemporal parameters of gait analysis, paediatric functional independence measure, and the Canadian Occupational Performance Measure. RESULTS: The 88-item Gross Motor Function Measure was significantly improved after training in the high-intensity (D Δ8.3 ± 15.6; E Δ3.8 ± 4.1) and comfortable intensity (D Δ2.9 ± 3.1; E Δ1.2 ± 2.0) groups, whereas gait speed was improved in the comfortable intensity group, without statistically significant group differences. Only the low-intensity group showed improvement on the stability index (Δ -0.6 ± 0.9, p = 0.05). Everyday functional performance significantly improved in all three groups, with the comfortable intensity group showing the greatest improvement. INTERPRETATION: Different training intensities produced improvement in different areas; individualized RAGT intensity adjustment is therefore needed based on the rehabilitation goal.


Assuntos
Paralisia Cerebral , Robótica , Humanos , Paralisia Cerebral/reabilitação , Paralisia Cerebral/fisiopatologia , Criança , Masculino , Feminino , Método Simples-Cego , Terapia por Exercício/métodos , Pré-Escolar , Resultado do Tratamento , Marcha/fisiologia , Transtornos Neurológicos da Marcha/reabilitação , Transtornos Neurológicos da Marcha/etiologia , Avaliação de Resultados em Cuidados de Saúde
3.
BMC Psychiatry ; 24(1): 294, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637786

RESUMO

OBJECTIVE: Problematic smartphone use has been linked to lower levels of mindfulness, impaired attentional function, and higher impulsivity. This study aimed to identify the psychological mechanisms of problematic smartphone use by exploring the relationship between addictive smartphone use, mindfulness, attentional function and impulsivity. METHODS: Ninety participants were evaluated with the smartphone addiction proneness scale and classified into the problematic smartphone use group (n = 42; 24 women; mean age: 27.6 ± 7.2 years) or normal use group (n = 48; 22 women; mean age: 30.1 ± 5.7 years). All participants completed self-report questionnaires evaluating their trait impulsivity and mindfulness and attention tests that assessed selective, sustained and divided attention. We compared the variables between the groups and explored the relationship between mindfulness, attentional function, impulsivity and addictive smartphone use through mediation analysis. RESULTS: The problematic smartphone use group showed higher trait impulsivity and lower mindfulness than the normal use group. There were no significant group differences in performance on attention tests. Levels of addictive smartphone use were significantly correlated with higher levels of trait impulsivity and lower levels of mindfulness, but not with performance on attention tests. Mediation analysis showed that acting with awareness, an aspect of mindfulness, reduces the degree of addictive smartphone use through attentional impulsivity, one of the trait impulsivity. CONCLUSION: Acting without sufficient awareness could influence addictive smartphone use by mediating attentional impulsivity. This supports that executive control deficits, reflected in high attentional impulsivity, contribute to problematic smartphone use. Our findings imply that mindfulness-based interventions can enhance executive control over smartphone use by promoting awareness.


Assuntos
Atenção Plena , Humanos , Feminino , Adulto Jovem , Adulto , Smartphone , Comportamento Impulsivo , Atenção , Inquéritos e Questionários
4.
J Clin Lab Anal ; 38(6): e25027, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38506403

RESUMO

BACKGROUND: Assessment of bone marrow involvement (BMI) in non-Hodgkin lymphoma (NHL) is crucial for determining patient prognosis and treatment strategy. We assessed the prognostic value of next-generation sequencing (NGS)-based immunoglobulin (Ig) gene clonality analysis as an ancillary test for BMI evaluation in NHL. METHODS: A retrospective cohort of 124 patients newly diagnosed with B-cell NHL between 2019 and 2022 was included. NGS-based Ig clonality analysis was conducted using LymphoTrak IGH FR1 Assay and IGK Assay (Invivoscribe Technologies, San Diego, CA, USA) on BM aspirate samples, and the results were compared with those of histopathological BMI (hBMI). RESULTS: Among the 124 patients, hBMI was detected in 16.9% (n = 21). The overall agreement of BMI between Ig clonality analyses and histopathological analysis for IGH, IGK, and either IGH or IGK was 86.3%, 92.7%, and 90.3%. The highest positive percent agreement was observed with clonal rearrangements of either IGH or IGK gene (90.5%), while the highest negative percent agreement was observed with clonal rearrangement of IGK gene (96.1%). For the prediction of hBMI, positive prediction value ranged between 59.1% and 80.0% and the negative prediction value ranged between 91.3% and 97.9%. CONCLUSION: NGS-based clonality analysis is an analytic platform with a substantial overall agreement with histopathological analysis. Assessment of both IGH and IGK genes for the clonal rearrangement analysis could be considered for the optimal diagnostic performance of BMI detection in B-cell NHL.


Assuntos
Linfoma de Células B , Linfoma não Hodgkin , Humanos , Genes de Imunoglobulinas , Medula Óssea/patologia , Estudos Retrospectivos , Linfoma de Células B/genética , Linfoma de Células B/diagnóstico , Linfoma de Células B/patologia , Linfoma não Hodgkin/genética , Sequenciamento de Nucleotídeos em Larga Escala
5.
Food Microbiol ; 119: 104435, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38225047

RESUMO

Aspergillus flavus and Aspergillus oryzae are closely related fungal species with contrasting roles in food safety and fermentation. To comprehensively investigate their phylogenetic, genomic, and metabolic characteristics, we conducted an extensive comparative pangenome analysis using complete, dereplicated genome sets for both species. Phylogenetic analyses, employing both the entirety of the identified single-copy orthologous genes and six housekeeping genes commonly used for fungal classification, did not reveal clear differentiation between A. flavus and A. oryzae genomes. Upon analyzing the aflatoxin biosynthesis gene clusters within the genomes, we observed that non-aflatoxin-producing strains were dispersed throughout the phylogenetic tree, encompassing both A. flavus and A. oryzae strains. This suggests that aflatoxin production is not a distinguishing trait between the two species. Furthermore, A. oryzae and A. flavus strains displayed remarkably similar genomic attributes, including genome sizes, gene contents, and G + C contents, as well as metabolic features and pathways. The profiles of CAZyme genes and secondary metabolite biosynthesis gene clusters within the genomes of both species further highlight their similarity. Collectively, these findings challenge the conventional differentiation of A. flavus and A. oryzae as distinct species and highlight their phylogenetic, genomic, and metabolic homogeneity, potentially indicating that they may indeed belong to the same species.


Assuntos
Aflatoxinas , Aspergillus oryzae , Aspergillus flavus/metabolismo , Filogenia , Aspergillus oryzae/genética , Aspergillus oryzae/metabolismo , Aflatoxinas/genética , Genômica
6.
Proc Natl Acad Sci U S A ; 118(9)2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33619098

RESUMO

Acetogenic bacteria use cellular redox energy to convert CO2 to acetate using the Wood-Ljungdahl (WL) pathway. Such redox energy can be derived from electrons generated from H2 as well as from inorganic materials, such as photoresponsive semiconductors. We have developed a nanoparticle-microbe hybrid system in which chemically synthesized cadmium sulfide nanoparticles (CdS-NPs) are displayed on the cell surface of the industrial acetogen Clostridium autoethanogenum The hybrid system converts CO2 into acetate without the need for additional energy sources, such as H2, and uses only light-induced electrons from CdS-NPs. To elucidate the underlying mechanism by which C. autoethanogenum uses electrons generated from external energy sources to reduce CO2, we performed transcriptional analysis. Our results indicate that genes encoding the metal ion or flavin-binding proteins were highly up-regulated under CdS-driven autotrophic conditions along with the activation of genes associated with the WL pathway and energy conservation system. Furthermore, the addition of these cofactors increased the CO2 fixation rate under light-exposure conditions. Our results demonstrate the potential to improve the efficiency of artificial photosynthesis systems based on acetogenic bacteria integrated with photoresponsive nanoparticles.


Assuntos
Acetatos/química , Proteínas de Bactérias/metabolismo , Compostos de Cádmio/química , Dióxido de Carbono/química , Clostridium/metabolismo , Elétrons , Nanopartículas/química , Sulfetos/química , Acetatos/metabolismo , Processos Autotróficos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Compostos de Cádmio/metabolismo , Dióxido de Carbono/metabolismo , Clostridium/genética , Clostridium/efeitos da radiação , Coenzimas/química , Coenzimas/metabolismo , Dinitrocresóis/química , Dinitrocresóis/metabolismo , Metabolismo Energético/genética , Regulação Bacteriana da Expressão Gênica , Luz , NAD/química , NAD/metabolismo , NADP/química , NADP/metabolismo , Nanopartículas/metabolismo , Fotossíntese/genética , Sulfetos/metabolismo , Transcrição Gênica
7.
Nano Lett ; 23(19): 8914-8922, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37722002

RESUMO

Transition-metal dichalcogenides (TMDs) and metal halide perovskites (MHPs) have been investigated for various applications, owing to their unique physical properties and excellent optoelectronic functionalities. TMD monolayers synthesized via chemical vapor deposition (CVD), which are advantageous for large-area synthesis, exhibit low mobility and prominent hysteresis in the electrical signals of field-effect transistors (FETs) because of their native defects. In this study, we demonstrate an increase in electrical mobility by ∼170 times and reduced hysteresis in the current-bias curves of MoS2 FETs hybridized with CsPbBr3 for charge transfer doping, which is implemented via solution-based CsPbBr3-nanocluster precipitation on CVD-grown MoS2 monolayer FETs. Electrons injected from CsPbBr3 into MoS2 induce heavy n-doping and heal point defects in the MoS2 channel layer, thus significantly increasing mobility and reducing hysteresis in the hybrid FETs. Our results provide a foundation for improving the reliability and performance of TMD-based FETs by hybridizing them with solution-based perovskites.

8.
J Pers Assess ; : 1-17, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940620

RESUMO

Self-dehumanization, a phenomenon relevant to social psychology, has been somewhat absent from clinical psychology research. Furthermore, measures of self-dehumanization are few, and to our knowledge, no validated and generalizable self-report measure exists. To address this gap, we present a Self-Dehumanization Scale (SDS). This work incorporates evidence from three studies examining the reliability, validity, and factor structure of the SDS in an undergraduate sample, a clinically relevant community sample, and a sample with at least one minoritized identity. The SDS was derived from dehumanization theory and was developed to measure animalistic and mechanistic self-dehumanization. All studies suggested an 8-item SDS, with Study 1 suggesting a single-factor solution with, however, some indication of a two-factor structure, and Studies 2 and 3 affirming a two-factor solution. The SDS, and its respective factors, generally showed discriminant validity from related, yet distinct, measures of self-hate, self-esteem (Study 2), dissociation, and measures of discrimination (in Study 3). Finally, animalistic and mechanistic SDS showed somewhat mixed but promising evidence regarding their associations to minoritized identities and to symptoms of depression, and suicide risk, above and beyond each study's fairly stringent control variables. Thus, self-dehumanization may prove to be a clinically promising leverage point in assessing psychopathology, particularly among minoritized communities.


This work develops and tests a generalizable measure of self-dehumanization, perceiving oneself as nonhuman, as a tool to further understand and assess psychopathology. Findings indicate a validated scale that shares relations to minoritized identity and to symptoms of depression and suicide risk above and beyond known risk factors.

9.
Clin Endocrinol (Oxf) ; 98(1): 110-116, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35394662

RESUMO

BACKGROUND: The tall cell variant papillary thyroid carcinoma (TCV-PTC) shows aggressive behaviour. Thus far, the diagnosis of TCV-PTC can only be confirmed using the postoperative specimen. This study aims to evaluate whether fine-needle aspiration (FNA) or core needle biopsy (CNB) could diagnose TCV-PTC preoperatively. METHODS: This is a retrospective cohort study. We included adult patients diagnosed with TCV-PTC or PTC with tall cell features (TCF) at final surgical pathology between January 2015 and December 2018. Preoperative histology was reviewed for six cytomorphologic features suggesting TCV-PTC in FNA or the percentage of tall cells in the CNB specimen. The postoperative pathology was also reviewed to confirm the percentage of tall cells. RESULTS: A total of 119 patients were included in this study; 35 (29%) patients with PTC with TCF served as controls. The most frequent cytomorphological feature in FNA samples of TCV-PTC was tall columnar cells, including single tombstone-like cells (70%). Among 43 TCV-PTC evaluated by FNA, 3 FNA (7%) revealed the absence of any of the six cytomorphologic features suggesting TCV-PTC. When we defined 30% of tall cells in CNB specimens as a cutoff suggesting TCV-PTC, only 16 (41%) TCV-PTCs could be preoperatively detected, and 3 (7%) TCV-PTCs did not have any tall cells. The proportion of tall cells was not associated with the postoperative percentage of tall cells. CONCLUSION: Both cytomorphologic features in FNA and the percentage of tall cells in CNB present limitations for use as accurate preoperative diagnostic tools of TCV-PTC.


Assuntos
Neoplasias da Glândula Tireoide , Humanos , Biópsia com Agulha de Grande Calibre , Biópsia por Agulha Fina , Câncer Papilífero da Tireoide/diagnóstico , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/diagnóstico
10.
FEMS Yeast Res ; 232023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36564017

RESUMO

In this review, we describe the genomic and physiological features of the yeast species predominantly isolated from Nuruk, a starter for traditional Korean rice wines, and Jang, a traditional Korean fermented soy product. Nuruk and Jang have several prevalent yeast species, including Saccharomycopsis fibuligera, Hyphopichia burtonii, and Debaryomyces hansenii complex, which belong to the CUG clade showing high osmotic tolerance. Comparative genomics revealed that the interspecies hybridization within yeast species for generating heterozygous diploid genomes occurs frequently as an evolutional strategy in the fermentation environment of Nuruk and Jang. Through gene inventory analysis based on the high-quality reference genome of S. fibuligera, new genes involved in cellulose degradation and volatile aroma biosynthesis and applicable to the production of novel valuable enzymes and chemicals can be discovered. The integrated genomic and transcriptomic analysis of Hyphopichia yeasts, which exhibit strong halotolerance, provides insights into the novel mechanisms of salt and osmo-stress tolerance for survival in fermentation environments with a low-water activity and high-concentration salts. In addition, Jang yeast isolates, such as D. hansenii, show probiotic potential for the industrial application of yeast species beyond fermentation starters to diverse human health sectors.


Assuntos
Glycine max , Vinho , Humanos , Filogenia , Leveduras/genética , Fermentação , Genômica , República da Coreia
11.
J Org Chem ; 88(9): 6263-6273, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37032486

RESUMO

We report the direct radiofluorosulfurylation method for the synthesis of 18F-labeled fluorosulfuryl derivatives from phenols and amines using an [18F]FSO2+ transfer agent generated in situ. Nucleophilic radiofluorination is achieved even in a hydrous organic medium, obviating the need for azeotropic drying and the use of cryptands. This unprecedented, operationally simple isotopic functionalization facilitates the reliable production of potential radiotracers for positron emission tomography, rendering facile access to SuFEx radiochemistry.

12.
Appl Microbiol Biotechnol ; 107(2-3): 569-580, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36517544

RESUMO

Astaxanthin is receiving increasing interest as an antioxidant and high value-added secondary metabolite. Haematococcus pluvialis is the main source for astaxanthin production, and many studies are being conducted to increase the production of astaxanthin. In this study, we linked polyethylenimine (PEI) with chitosan to maintain astaxanthin-inducing ability while securing the recyclability of the inducer. Astaxanthin accumulation in H. pluvialis was induced to 86.4 pg cell-1 with the PEI-chitosan fiber (PCF) treatment prepared by cross-linking of 10 µM PEI and low molecular weight (MW) chitosan via epichlorohydrin. PEI concentration affected the astaxanthin accumulation, whereas the MW of chitosan did not. In addition, the PCF treatment in H. pluvialis increased the reactive oxygen species (ROS) content in cells, thereby upregulating the transcription of enzymes involved in astaxanthin biosynthesis. PCF can be reused multiple times with the maintenance of over 90% of the astaxanthin production efficiency. This study offers a reusable PCF stimulation strategy for enhancing natural astaxanthin content, and PCF treatment will easily increase the production scale or reduce production costs by using recyclability that is not available in current methods. KEY POINTS: • Polyethylenimine-chitosan fiber (PCF) was applied to Haematococcus pluvialis • PCF promotes astaxanthin accumulation by enhancing oxidative stress in H. pluvialis • PCF can be reused multiple times with maintaining over 90% production efficiency.


Assuntos
Quitosana , Polietilenoimina , Polietilenoimina/metabolismo , Quitosana/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
13.
Int J Med Sci ; 20(2): 186-193, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36794152

RESUMO

Background: Cytomegalovirus (CMV) reactivation is a common complication in patients undergoing allogeneic stem cell transplantation. However, the incidence of CMV reactivation is low after autologous stem cell transplantation (auto-SCT), and the prognostic value of CMV reactivation remains controversial. Moreover, reports on late CMV reactivation after auto-SCT are limited. We aimed to analyze the association between CMV reactivation and survival outcomes and develop a predictive model for late CMV reactivation in patients undergoing auto-SCT. Methods: Data of 201 patients who underwent SCT at the Korea University Medical Center from 2007 to 2018 were collected. We analyzed prognostic factors for survival outcomes after auto-SCT and risk factors for late CMV reactivation using a receiver operating characteristic curve. Then, we developed a predictive risk model for late CMV reactivation based on results of the risk factor analysis. Results: Early CMV reactivation was significantly associated with better overall survival (OS) (hazard ratio [HR], 0.329; P = 0.045) in patients with multiple myeloma; however, no significant differences were observed in patients with lymphoma. For late CMV reactivation, a serum lactate dehydrogenase level greater than the upper limit of normal (HR, 2.251; P = 0.027) and late CMV reactivation (HR, 2.964; P = 0.047) were independent risk factors for poor OS, while lymphoma diagnosis (vs. multiple myeloma; HR, 0.389; P = 0.016) was an independent risk factor for good OS. In risk factor analysis for late CMV reactivation, T-cell lymphoma diagnosis (odds ratio [OR], 8.499; P = 0.029), ≥ two prior chemotherapies (OR, 8.995; P = 0.027), failure to achieve complete response (CR) after transplantation (OR, 7.124; P = 0.031), and early CMV reactivation (OR, 12.853; P = 0.007) were significantly associated with late CMV reactivation. To develop the predictive risk model for late CMV reactivation, a score (1 to 1.5) was assigned for each of the above-mentioned variables. The optimal cutoff value (1.75 points) was calculated using the receiver operating characteristic curve. The predictive risk model showed good discrimination, with an area under the curve of 0.872 (standard error, 0.062; P < 0.001). Conclusions: Late CMV reactivation was an independent risk factor for inferior OS, whereas early CMV reactivation was associated with better survival in patients with multiple myeloma. This risk prediction model could be helpful in identifying high-risk patients who require monitoring for late CMV reactivation and potentially benefit from prophylactic or preemptive therapy.


Assuntos
Infecções por Citomegalovirus , Transplante de Células-Tronco Hematopoéticas , Linfoma , Mieloma Múltiplo , Humanos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Citomegalovirus , Mieloma Múltiplo/terapia , Infecções por Citomegalovirus/etiologia , Transplante Autólogo/efeitos adversos , Prognóstico , Linfoma/complicações , Estudos Retrospectivos
14.
Health Educ Res ; 38(6): 587-596, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37436827

RESUMO

Cervical cancer screening and human papillomavirus (HPV) vaccination are critical for those immunocompromised due to human immunodeficiency virus (HIV). Health education programs, including text messaging, can effectively improve knowledge of cervical cancer and recommended screening. This paper describes the data-driven development of a 4-week text-messaging intervention to improve HPV and cervical cancer knowledge among women living with HIV (WLH). This study reports data from surveys (n = 81; January 2020 to September 2021) and focus group discussions (FGDs, n = 39; April-June 2020) conducted among WLH in the DC area. While most WLH revealed that their usual sources of health information were through in-person group sessions, they pointed out that these were impractical options due to the coronavirus 2019 pandemic. They noted that a text-messaging intervention was feasible and acceptable. FGD participants' responses structured around the Protection Motivation Theory constructs informed the text-messaging library, covering topics such as (I) understanding of cervical cancer and HPV, (II) cervical cancer prevention and (III) HPV self-sampling. The utilization of low-cost and easily accessible health education interventions, such as mobile-based text messaging, can effectively increase knowledge and awareness of cervical cancer in populations that have been historically difficult to access and during times when health services are disrupted such as during a global pandemic or public health emergency.


Assuntos
Infecções por HIV , Infecções por Papillomavirus , Envio de Mensagens de Texto , Neoplasias do Colo do Útero , Humanos , Feminino , HIV , Neoplasias do Colo do Útero/prevenção & controle , Neoplasias do Colo do Útero/diagnóstico , Detecção Precoce de Câncer , Infecções por Papillomavirus/prevenção & controle , Infecções por HIV/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde
15.
Ecotoxicol Environ Saf ; 262: 115189, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37385021

RESUMO

Heavy metals such as lead (Pb), cadmium (Cd), and arsenic (As) are of great concern in aquatic ecosystems because of their global distribution, persistence, and biomagnification via the food web. They can induce the expression of cellular protective systems (e.g., detoxification enzymes and antioxidant enzymes) to protect organisms from oxidative stress, which is a high-energy-consuming process. Thus, energy reserves (e.g., glycogen, lipids, and proteins) are utilized to maintain metabolic homeostasis. Although a few studies have suggested that heavy metal stress can modulate the metabolic cycle in crustaceans, information on changes in energy metabolism under metal pollution remains lacking in planktonic crustaceans. In the present study, the activity of digestive enzymes (amylase, trypsin, and lipase) and the contents of energy storage molecules (glycogen, lipid, and protein) were examined in the brackish water flea Diaphanosoma celebensis exposed to Cd, Pb, and As for 48 h. Transcriptional modulation of the three AMP-activated protein kinase (AMPK) and metabolic pathway-related genes was further investigated. Amylase activity was highly increased in all heavy metal-exposed groups, whereas trypsin activity was reduced in Cd- and As-exposed groups. While glycogen content was increased in all exposed groups in a concentration-dependent manner, lipid content was reduced at higher concentrations of heavy metals. The expression of AMPKs and metabolic pathway-related genes was distinct among heavy metals. In particular, Cd activated the transcription of AMPK-, glucose/lipid metabolism-, and protein synthesis-related genes. Our findings indicate that Cd can disrupt energy metabolism, and may be a potent metabolic toxicant in D. celebensis. This study provides insights into the molecular mode of action of heavy metal pollution on the energy metabolism in planktonic crustaceans.

16.
Sensors (Basel) ; 23(20)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37896657

RESUMO

In electronic warfare systems, detecting low-probability-of-intercept (LPI) radar signals poses a significant challenge due to the signal power being lower than the noise power. Techniques using statistical or deep learning models have been proposed for detecting low-power signals. However, as these methods overlook the inherent characteristics of radar signals, they possess limitations in radar signal detection performance. We introduce a deep learning-based detection model that capitalizes on the periodicity characteristic of radar signals. The periodic autocorrelation function (PACF) is an effective time-series data analysis method to capture the pulse repetition characteristic in the intercepted signal. Our detection model extracts radar signal features from PACF and then detects the signal using a neural network employing long short-term memory to effectively process time-series features. The simulation results show that our detection model outperforms existing deep learning-based models that use conventional autocorrelation function or spectrogram as an input. Furthermore, the robust feature extraction technique allows our proposed model to achieve high performance even with a shallow neural network architecture and provides a lighter model than existing models.

17.
Environ Geochem Health ; 45(9): 6807-6822, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36445536

RESUMO

Owing to their widespread distribution and high bioaccumulation, microplastics (MPs) and mercury (Hg) are considered major threats to the ocean. MP interacts with Hg because of its high adsorption properties. However, their toxicological interactions with marine organisms, especially combined effects at the molecular level, are poorly understood. This study investigated the single and combined effects of MP and Hg on the metabolic profile of the brackish water flea Diaphanosoma celebensis. A total of 238 metabolites were significantly affected by MP, Hg, or MP + Hg. Metabolite perturbation patterns showed that toxicity of Hg and MP + Hg was similar and that of MP was not significant. Among the 223 metabolites affected by Hg, profiles of 32 unannotated metabolites were significantly different from those of MP + Hg, and combined effects of MP + Hg decreased the effect of Hg on 25 of these metabolites. Only 11 annotated metabolites were significantly affected by Hg or MP + Hg and were related to carbohydrate, lipid, vitamin, and ecdysteroid metabolism. Ten metabolites were decreased by Hg and MP + Hg and were not significantly different between the exposure groups. Enrichment analysis showed that galactose, starch, and sucrose metabolism were the most affected pathways. These findings suggest that MP has negligible toxic effect, and Hg can induce energy depletion, membrane damage, and disruption of growth, development, and reproduction. Although the impact of MP was negligible, the combined effects of MP + Hg could be metabolite specific. This study provides better understanding of the combined effects of MP and Hg on marine organisms.


Assuntos
Cladocera , Mercúrio , Compostos de Metilmercúrio , Poluentes Químicos da Água , Animais , Organismos Aquáticos , Mercúrio/análise , Mercúrio/toxicidade , Compostos de Metilmercúrio/toxicidade , Microplásticos/toxicidade , Plásticos , Águas Salinas , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise
18.
Environ Microbiol ; 24(1): 122-136, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34708498

RESUMO

Because the bacterial phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS) is involved in the regulation of various physiological processes in addition to carbohydrate transport, its expression is precisely regulated in response to the availability of PTS sugars. The PTS consists of enzyme I and histidine phosphocarrier protein, and several sugar-specific enzymes II. In Escherichia coli, genes for enzymes II specific for glucose and related sugars are co-regulated by the global repressor Mlc, and glucose induction of the Mlc regulon genes is achieved by its interaction with glucose-specific enzyme II (EIIGlc ). In this study, we revealed that, in Vibrio species, which are phylogenetically older than Enterobacteriaceae, the membrane sequestration of Mlc and thereby the induction of its regulon genes is mediated by N-acetylglucosamine (NAG)-specific EII. While Vibrio Mlc interacts only with the EIIB domain of EIINag , E. coli Mlc interacts with the EIIB domain of both EIIGlc and EIINag . The present data suggest that EIINag may be the primordial regulator of Mlc, and EIIGlc has evolved to interact with Mlc since an EIIA domain was fused to EIINag in Enterobacteriaceae. Our findings provide insight into the coevolutionary dynamics between a transcription factor and its cognate regulator according to long-term resource availability in the bacterial natural habitat.


Assuntos
Proteínas de Escherichia coli , Sistema Fosfotransferase de Açúcar do Fosfoenolpiruvato , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica , Glucose/metabolismo , Sistema Fosfotransferase de Açúcar do Fosfoenolpiruvato/genética , Sistema Fosfotransferase de Açúcar do Fosfoenolpiruvato/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
19.
Small ; 18(10): e2103523, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35023602

RESUMO

Fluorescence imaging is an indispensable tool in modern biological research, allowing simple and inexpensive color-coded visualizations of real-time events in living cells and animals, as well as of fixed states of ex vivo specimens. The accuracy of fluorescence imaging in living systems is, however, impeded by autofluorescence, light scattering, and limited penetration depth of light. Nevertheless, the clinical use of fluorescence imaging is expected to grow along with advances in imaging equipment, and will increasingly demand high-accuracy probes to avoid false-positive results in disease detection. To this end, a water-soluble and relatively safe diarylethene (DAE)-based reversible near-infrared (NIR) fluorescence photoswitch for living systems is prepared here. Furthermore, to facilitate excellent switching performance, the photoirradiation results obtained is compared using three different visible light sources to turn on NIR fluorescence through cycloreversion of DAE. While photoswitching using 589 nm light leads to slightly higher cell viability, fluorescence quenching efficiency and fatigue resistance are higher when 532 nm light with low photobleaching is used in both aqueous solution and living systems. The authors anticipate that their reversible NIR fluorescence photoswitch mediated by DAE can be beneficial for fluorescence imaging in aqueous media requiring accurate detection, such as in the autofluorescence-rich living environment.


Assuntos
Corantes Fluorescentes , Imagem Óptica , Animais , Água
20.
Small ; 18(25): e2200316, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35570584

RESUMO

To circumvent the limitations of conventional cancer immunotherapy, it is critical to prime antigen-presenting cells (APCs) to initiate the cancer-immune cycle. Here, the authors develop a metal-phenolic network (MPN)-based immunoactive nanoparticle in combination with irreversible electroporation (IRE) for an effective cancer immunotherapy. The MPN nanoparticles are synthesized by coordinating tannic acid with manganese (Mn) ions, and subsequent coating with CpG-oligodeoxynucleotides (CpG-ODNs) via hydrogen bonding. The CpG-ODN-coated Mn-phenolic network (CMP) nanoparticles are effectively internalized into macrophages, a type of APCs, and successfully trigger M1 polarization to promote release of proinflammatory cytokines. Notably, the CMP nanoparticles demonstrate an extended retention time period than the free CpG-ODN in the tumor. The tumor microenvironment tailored bipolar IRE, enhances the therapeutic efficacy by significantly broadening the ablation zone, which further increases immunogenic cell death (ICD). Ultimately, the simultaneous CMP nanoparticles and IRE treatment successfully inhibit tumor growth and prolong survival in a mouse tumor model. Thus, CMP nanoparticles are empowered with Mn and CpG-ODN immunomodulators and the tumor microenvironment tailored bipolar IRE will be a new tool for effective cancer immunotherapy to treat intractable malignancies.


Assuntos
Nanopartículas , Neoplasias , Animais , Camundongos , Eletroporação , Imunoterapia , Neoplasias/terapia , Microambiente Tumoral
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