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1.
ACS Omega ; 9(25): 27407-27414, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38947825

RESUMO

Hydrogen is emerging as a promising zero-carbon emission energy source for vehicle engines. However, the full potential of hydrogen engines and their economic viability remain uncertain. Additionally, comprehensive data on ultralean combustion performance and emissions as well as strategies for improving HC and CO emissions are lacking. This study addresses these gaps by thoroughly examining hydrogen combustion and emissions in a 1.5 L engine. Incorporating a hydrogen direct injection (HDI) system and an electric supercharger, we investigated emissions under various piston ring tensions during lean limit operations. Our findings reveal that hydrogen exhibits a fast combustion speed in the engine within 20 °CA, along with excellent ultralean burn performance, expanding the lambda limit to 3. As the load increases, the thermal efficiency significantly improves, reaching a maximum of 40.8%. NOx emissions peak at a lambda of 1.1 but decrease notably above 2.7, with levels below 10 ppm. At a lambda near 3, NOx emissions hover between 0 and 5 ppm, approaching zero emissions. Additionally, lubricating oil consumption during engine operation yields a minor HC and CO emissions. Higher tension piston rings result in lower HC and CO emissions, typically below 5 ppm, nearing zero emission levels.

2.
J Voice ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38969543

RESUMO

OBJECTIVES: To compare the effects of telerehabilitation (TR) and face-to-face rehabilitation (FTF) methods on the outcomes of adults with voice disorders and to analyze the effectiveness of TR. METHODS: Following Boolean Logic, a search strategy was devised, combining subject terms and keywords based on the interventions and populations outlined in the inclusion criteria. We searched PubMed, Cochrane Library, Embase, Web of Science, Scopus, CNKI, Wanfang, CQVIP databases, and manually screened academic conference papers, journal articles, and gray literature to identify eligible randomized controlled trials (RCTs) on remote voice therapy. Two researchers assessed the risk of bias in the included studies using the risk of bias assessment tool for RCTs outlined in the Cochrane Handbook for Systematic Reviews of Interventions version 5.1.0. RESULTS: Five trials with a total of 233 patients with voice disorders were included in the study after screening. The results revealed a significant difference in Jitter change values (mean difference [MD]=-0.12, 95%CI [-0.23,-0.01], P = 0.04) between TR and FTF, maximum phonation time (MD=0.76, 95%CI [-0.60,2.13], P = 0.27), Shimmer (MD=-0.04, 95%CI [-0.11,0.03], P = 0.27), voice handicap index (MD=0.87, 95%CI [-1.77,3.50], P = 0.52), and GRBAS(G) (MD=-0.00, 95%CI [-0.01,0.01], P = 0.99) had no significant difference. CONCLUSION: TR demonstrates comparable efficacy to FTF in voice treatment and is associated with higher levels of patient satisfaction, making it a viable and effective therapeutic modality. However, given the limited sample size analyzed in this study, further validation of this conclusion necessitates additional RCTs with larger sample sizes. Furthermore, researchers should remain cognizant of the constraints associated with TR and consistently refine treatment protocols to enhance the efficacy of voice therapy.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38581320

RESUMO

Objective: Language developmental delay is a common developmental disorder in children. This study stands out by conducting a comparative analysis between conventional intervention and early comprehensive intervention in children under and over 3 years of age. Unlike previous studies, our research delves into the distinctive impacts of these interventions on various developmental aspects, such as adaptive behavior, gross and fine motor skills, language, and personal social behavior. Methods: The research subjects were children diagnosed with language developmental delay who received intervention treatment at Quanzhou Children's Hospital between January 2021 and December 2022. After excluding children who did not meet the complete inclusion criteria, a total of 80 cases were included in the study. First, the clinical characteristics of all children were analyzed by separating the children by age and quantifying developmental quotients. Subsequently, the children were divided into either a control group or a research group. Children in both groups received conventional intervention, and those in the research group were also given early comprehensive intervention. Each group consisted of 40 children, and the intervention effects of the 2 groups were compared and discussed. Results: Children over 3 years of age had significantly lower developmental quotient values in various developmental areas (adaptive behavior, gross motor skills, fine motor skills, language, and personal social behavior) than those under 3 years of age (all P < .001). After the intervention, the assessment results of the research group using the Sign-Significant Language Developmental Delay Assessment Method were significantly better than those of the control group (all P < .001). After the intervention, the research group showed significant increases in speech and language expression, auditory perception and comprehension, visual-related understanding and expression, and total score, as assessed using the Early Language Development Progress Scale, compared with the control group (P = .034 for poor communication attitude, P = .028 for abnormal motor issues, and P = .042 for abnormal language comprehension abilities). After the intervention, all indicators of social behavior abilities in the research group were significantly higher than those in the control group (P = .019 for independent living skills, P = .024 for motor skills, P = .047 for homework performance, P = .017 for social interactions, P = .035 for group activity capabilities, and P = .022 for self-management ability scores), as assessed by the Infant to Middle School Social Life Skills Scale. Conclusion: Language developmental delay is a common childhood developmental disorder with a higher prevalence among males. Most cases are observed in children under 3 years of age, and as they age, they are more likely to develop global developmental delays. Early comprehensive intervention can significantly improve children's developmental status and enhance their social behavior abilities. Understanding the clinical characteristics of language developmental delay and early diagnosis, as well as implementing comprehensive intervention measures, are crucial for helping children overcome language difficulties. Through collaborative efforts, we can assist these children in realizing their full potential and achieving better language and social development.

4.
Folia Phoniatr Logop ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38547847

RESUMO

INTRODUCTION: Vowel production in dysarthria tends to be centralized, which is affected by many factors. This study examined the acoustic effects of speaker sex, tones, and speech samples (including sustained vowels, syllables, and sentences) and their interactions on vowel production in Mandarin speakers with post-stroke spastic dysarthria. METHODS: 28 patients with post-stroke spastic dysarthria (18 males, 10 females) and 21 healthy speakers (11 males and 10 females) with no significant difference in sex and age with dysarthria were recruited. They were asked to read sustained vowels /a, i, u/, 12 syllables and 12 sentences containing three vowels in four tones (ba, bá, bǎ, bà, bi, bí, bǐ, bì, pu, pú, pǔ, pù). Multiple spectral and temporal acoustic metrics were analyzed. RESULTS: Results showed that regardless of the speech samples or tones, vowel production was more centralized in dysarthria than healthy controls, manifested as the decrease in F1 range, F2 range, vowel space area (VSA), and vowel articulation index (VAI). A similar performance was observed for male speakers compared to females, and vowel duration in males was shorter than females. F1 range, F2 range, VSA, VAI, and vowel duration were significantly different across speech samples and tones, decreasing in the order of vowel-syllable-sentence and T3-T2-T1-T4, respectively. Interactions of group, speaker sex, speech sample, and tone were more sensitive in VAI and vowel duration. CONCLUSION: VAI and vowel duration were recommended as the prior metrics to the assessment of vowel production. Specific influencing factors (speaker sex, speech sample, and tone) of vowel production need to be considered by speech and language pathologists in the assessment and rehabilitation.

5.
ACS Omega ; 9(8): 8893-8903, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38434811

RESUMO

This experimental study investigates the impact of water injection into intake ports on combustion and emissions in gasoline engines. It also examines particle size distribution at various water-to-fuel ratios and explores the combined effects of water injection and compression ratios in gasoline engines. The results indicate that water injection effectively mitigates engine knock, reduces peak firing pressures, and moderates heat release rates through charge cooling. Advancing ignition timing with water injection advances combustion, resulting in reduced specific fuel consumption, particularly under moderate load conditions. Water injection lowers NOx emissions by reducing combustion temperatures but increases unburned THC emissions due to inhibited oxidation reaction rates. Minor effects were observed on CO emissions. Furthermore, particle numbers were significantly reduced with water injection, particularly in the nucleation mode particles. The simultaneous application of a higher compression ratio and water injection yields substantial improvements in fuel consumption with minimal impact on NOx and THC emissions.

6.
ACS Omega ; 8(42): 39427-39436, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37901578

RESUMO

Hydrogen is an ideal alternative fuel for internal combustion engines due to its fast combustion rate and near-zero carbon emissions. To further investigate the impact of the injection strategy on combustion performance under various excess air coefficients and loads, experimental methods were employed to systematically study injection timing, injection pressure, and dual injection. The results demonstrate that appropriately delaying hydrogen injection timing can improve the thermal efficiency by up to 2.6% and reduce NOx emissions of equivalent combustion by nearly 88%. While increasing the hydrogen pressure to 8 MPa does not directly enhance the thermal efficiency and emissions, it can reduce the injection pulse width by approximately 75%, allowing for more flexibility in delaying the injection timing. Delaying the secondary end of injection (SEOI) leads to a reduction of over 47% in NOx emissions for λ (excess air coefficient) values of 1.5 and 1.0. The combustion duration and ignition delay initially increase and then decrease with the delay in SEOI, depending on the movement state of the fuel jet. With the increase in secondary injection proportion (SIP), brake thermal efficiency increases by no more than 1%, but NOx is reduced by more than 43% for λ values of 1.5 and 1.0. In the case of ultralean conditions (λ = 2.3), increasing the SIP from 0 to 30% results in a nearly 14% increase in the peak heat release rate (HRR) and a 19% reduction in combustion duration.

7.
J Colloid Interface Sci ; 650(Pt A): 203-210, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37402326

RESUMO

Achieving all-solid-state lithium-based batteries with high energy densities requires lightweight and ultrathin solid-state electrolytes (SSEs) with high Li+ conductivity, but this still poses significant challenges. Herein, we designed a robust and mechanically flexible SSE (denoted BC-PEO/LiTFSI) by using an environmentally friendly and low-cost approach that involves bacterial cellulose (BC) as a three-dimensional (3D) rigid backbone. In this design, BC-PEO/LiTFSI is tightly integrated and polymerized through intermolecular hydrogen bonding, and the rich oxygen-containing functional groups from the BC filler also provide the active site for Li+ hopping transport. Therefore, the all-solid-state Li-Li symmetric cell with BC-PEO/LiTFSI (containing 3% BC) showed excellent electrochemical cycling properties over 1000 h at a current density of 0.5 mA cm-2. Furthermore, the Li-LiFePO4 full cell showed steady cycling performance under 3 mg cm-2 areal loading at a current of 0.1 C, and the resultant Li-S full cell maintained over 610 mAh g-1 for upward of 300 cycles at 0.2 C and 60 °C.

8.
Chin Med J (Engl) ; 136(11): 1278-1290, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37130223

RESUMO

ABSTRACT: Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease characterized by progressive lung fibrogenesis and histological features of usual interstitial pneumonia. IPF has a poor prognosis and presents a spectrum of disease courses ranging from slow evolving disease to rapid deterioration; thus, a differential diagnosis remains challenging. Several biomarkers have been identified to achieve a differential diagnosis; however, comprehensive reviews are lacking. This review summarizes over 100 biomarkers which can be divided into six categories according to their functions: differentially expressed biomarkers in the IPF compared to healthy controls; biomarkers distinguishing IPF from other types of interstitial lung disease; biomarkers differentiating acute exacerbation of IPF from stable disease; biomarkers predicting disease progression; biomarkers related to disease severity; and biomarkers related to treatment. Specimen used for the diagnosis of IPF included serum, bronchoalveolar lavage fluid, lung tissue, and sputum. IPF-specific biomarkers are of great clinical value for the differential diagnosis of IPF. Currently, the physiological measurements used to evaluate the occurrence of acute exacerbation, disease progression, and disease severity have limitations. Combining physiological measurements with biomarkers may increase the accuracy and sensitivity of diagnosis and disease evaluation of IPF. Most biomarkers described in this review are not routinely used in clinical practice. Future large-scale multicenter studies are required to design and validate suitable biomarker panels that have diagnostic utility for IPF.


Assuntos
Fibrose Pulmonar Idiopática , Doenças Pulmonares Intersticiais , Humanos , Fibrose Pulmonar Idiopática/diagnóstico , Biomarcadores , Pulmão , Líquido da Lavagem Broncoalveolar , Progressão da Doença , Prognóstico
9.
Molecules ; 28(10)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37241866

RESUMO

Two-dimensional materials have been developed as novel photovoltaic and photocatalytic devices because of their excellent properties. In this work, four δ-IV-VI monolayers, GeS, GeSe, SiS and SiSe, are investigated as semiconductors with desirable bandgaps using the first-principles method. These δ-IV-VI monolayers exhibit exceptional toughness; in particular, the yield strength of the GeSe monolayer has no obvious deterioration at 30% strain. Interestingly, the GeSe monolayer also possesses ultrahigh electron mobility along the x direction of approximately 32,507 cm2·V-1·s-1, which is much higher than that of the other δ-IV-VI monolayers. Moreover, the calculated capacity for hydrogen evolution reaction of these δ-IV-VI monolayers further implies their potential for applications in photovoltaic and nano-devices.

10.
Medicine (Baltimore) ; 102(6): e32900, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36820601

RESUMO

BACKGROUND: Benefits of intensive speech treatment have been documented for a range of speech signs in English speakers with Parkinson's Disease (PD). However, the answer to a critical question that whether the same treatment benefits speech variables including intelligibility in Mandarin speakers is still unclear. In order to develop a targeted speech treatment for Mandarin speakers with PD, we reviewed the efficacy of intensive speech treatment to improve vocal loudness and functional communication and discuss possible explanations for efficacy on Mandarin speakers with PD. METHODS: Literatures about intensive speech treatment for Mandarin speakers with PD were retrieved from PubMed, Web of Science, Embase, China National Knowledge Infrastructure (CNKI), Wanfang and Weipu Database for Chinese Technical Periodicals (VIP) Database. Search strategy was (voice therapy OR speech therapy OR voice treatment OR speech treatment OR voice training OR speech training OR voice rehabilitation OR speech rehabilitation OR Lee Silverman voice treatment OR intensive speech treatment) and (Parkinson's disease) and (Mandarin speakers OR Chinese OR Chinese people). RESULTS: Five randomized controlled trials were selected and possible explanations for efficacy on individuals with PD are discussed. Further research directions are suggested. CONCLUSION: The existing evidence from treatment efficacy studies of intensive speech treatment provides support for improving vocal loudness, speech intelligibility, pitch and rate in Mandarin speakers with PD. Our future research will continue to work to conduct a large sample multicenter randomized controlled trial to provide high quality evidence and understand the basic mechanisms accompanying treatment-related change.


Assuntos
Doença de Parkinson , Distúrbios da Voz , Voz , Humanos , Fala , Doença de Parkinson/diagnóstico , Inteligibilidade da Fala , Fonoterapia , Estudos Multicêntricos como Assunto
11.
Front Hum Neurosci ; 17: 1298974, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38259334

RESUMO

Introduction: Speech production includes segmental and suprasegmental features, which interact and cooperate with each other. Impaired speech production is common in individuals with post-stroke dysarthria. The commonly used phonemic contrast therapy and Accent Method in clinical practice can improve the segmental and suprasegmental aspects, respectively. This study aimed to explore the feasibility and immediate effectiveness of the combination of specific rhythm patterns of the Accent Method and phonemic contrast on speech production. Methods: Fifteen poststroke dysarthria patients (12 males and three females) first received accentuation task of three rhythm patterns (Largo-slow, Andante-medium, Allegro-fast) and later received speech task in appropriate rhythm patterns combined with phonemic contrast materials and non-phonemic contrast materials. Speech parameters were analyzed by considering speech clarity and prosody. Results: The results showed that the number of correct target syllables, sentence clarity, and standard deviation of intensity increased significantly, and the average length of pauses and abnormal pause times decreased significantly in Andante (medium) compared to other rhythms. The number of correct target syllables, sentence clarity, and standard deviation of intensity increased significantly compared with those in the non-phonemic contrast in Andante (medium). Conclusion: The combination of phonemic contrast and Accent Method was verified to have an immediate effect on speech production in Mandarin speakers with post-stroke dysarthria and could be further validated in other diseases with impaired speech production in the clinic in the future.

12.
Front Chem ; 10: 879402, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464209

RESUMO

Using two-dimensional (2D) heterostructure as photocatalyst for water splitting is a popular strategy for the generation of hydrogen. In this investigation, the first-principles calculations are explored to address the electronic performances of the 2D CdO/HfS2 heterostructure formed by van der Waals (vdW) forces. The CdO/HfS2 vdW heterostructure has a 1.19 eV indirect bandgap with type-II band alignment. Importantly, the CdO/HfS2 vdW heterostructure possesses an intrinsic Z-scheme photocatalytic characteristic for water splitting by obtaining decent band edge positions. CdO donates 0.017 electrons to the HfS2 layer in the heterostructure, inducing a potential drop to further separate the photogenerated electrons and holes across the interface. The CdO/HfS2 vdW heterostructure also has excellent optical absorption capacity, showing a promising role as a photocatalyst to decompose the water.

13.
Front Chem ; 10: 847319, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35237564

RESUMO

Recently, the energy shortage has become increasingly prominent, and hydrogen (H2) energy has attracted extensive attention as a clean resource. Two-dimensional (2D) materials show excellent physical and chemical properties, which demonstrates considerable advantages in the application of photocatalysis compared with traditional materials. In this investigation, based on first-principles methods, 2D PtS2 and MoTe2 are selected to combine a heterostructure using van der Waals (vdW) forces, which suggests a type-II band structure to prevent the recombination of the photogenerated charges. Then, the calculated band edge positions reveal the decent ability to develop the redox reaction for water splitting at pH 0. Besides, the potential drop between the PtS2/MoTe2 vdW heterostructure interface also can separate the photogenerated electrons and holes induced by the charge density difference of the PtS2 and MoTe2 layers. Moreover, the fantastic optical performances of the PtS2/MoTe2 vdW heterostructure further explain the promising advanced usage for photocatalytic decomposition of water.

14.
Clin Linguist Phon ; 35(8): 779-792, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32985269

RESUMO

Impairment of vowel production in dysarthria has been highly valued. This study aimed to explore the vowel production of Mandarin-speakers with post-stroke spastic dysarthria in connected speech and to explore the influence of gender and tone on the vowel production. Multiple vowel acoustic metrics, including F1 range, F2 range, vowel space area (VSA), vowel articulation index (VAI) and formant centralization ratio (FCR), were analyzed from vowel tokens embedded in connected speech produced. The participants included 25 clients with spastic dysarthria secondary to stroke (15 males, 10 females) and 25 speakers with no history of neurological disease (15 males, 10 females). Variance analyses were conducted and the results showed that the main effects of population, gender, and tone on F2 range, VSA, VAI, and FCR were all significant. Vowel production became centralized in the clients with post-stroke spastic dysarthria. Vowel production was found to be more centralized in males compared to females. Vowels in neutral tone (T0) were the most centralized among the other tones. The quantitative acoustic metrics of F2 range, VSA, VAI, and FCR were effective in predicting vowel production in Mandarin-speaking clients with post-stroke spastic dysarthria, and hence may be used as powerful tools to assess the speech performance for this population.


Assuntos
Benchmarking , Disartria , Acústica , Disartria/etiologia , Feminino , Humanos , Masculino , Fonética , Acústica da Fala , Medida da Produção da Fala
15.
Transl Cancer Res ; 10(2): 1082-1087, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35116435

RESUMO

BACKGROUND: This study aimed to explore the prognostic function of p53 and Ki-67 protein expression in chemotherapy sensitivity and prognosis in triple-negative breast cancer (TNBC). METHODS: Patients who were confirmed with TNBC in Wenzhou Geriatric Hospital and Wenzhou Hospital of Traditional Chinese Medicine (including the Oncology Department, Tumor Surgery Department, and Gynecology Department) between January 2006 and February 2018 were included in this study. The expression of p53 and Ki-67 detected by immunohistochemistry, the rate of recurrence, and the objective curative effect evaluation at the end of the first-line rescue treatment were recorded for all patients. RESULTS: The patients were followed up to August 2020, and the median follow-up time was 9 years and 4 months. A total of 285 patients with TNBC were enrolled in the study. The patients ranged in age from 19 to 76 years old, with an average age of 53 years. The overall recurrence rate among the patients was 31.58%. The majority of cases (68.07%) were pathological stage I. The overall positive expression rates of Ki-67 and p53 were 53.33% and 56.84%, respectively. In the TNBC recurrence group, the positive rates of p53 and Ki-67 were 71.11% and 82.22%, respectively, which were significantly higher than those in the non-recurrence group. The positive rates of p53 and Ki-67 in the chemosensitive group were 96.05% and 92.11%, respectively, which were significantly higher than those in the non-chemosensitive group. Among all the TNBC patients, 128 patients had positive expression of both p53 and Ki-67, and 101 patients had negative expression of both p53 and Ki-67. The chemosensitivity rate of TNBC patients with positive expression of both Ki-67 and p53 was 98.53%, and that of TNBC patients with negative expression of both Ki-67 and p53 was 0.00%. The difference was statistically significant. The recurrence rate in TNBC patients with positive expression of both Ki-67 and p53 was 53.13%, and that in patients with negative expression of both Ki-67 and p53 was 6.93%. The difference was statistically significant. CONCLUSIONS: The expression of p53 and Ki-67 had prognostic relevance to chemotherapy sensitivity and prognosis in TNBC patients.

16.
RSC Adv ; 11(47): 29576-29584, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35479544

RESUMO

Two-dimensional (2D) materials have attracted numerous investigations after the discovery of graphene. 2D van der Waals (vdW) heterostructures are a new generation of layered materials, which can provide more desirable applications. In this study, the first principles calculation was implemented to study the heterostructures based on Janus TMDs (MoSSe and WSSe) and Mg(OH)2 monolayers, which were constructed by vdW interactions. Both MoSSe/Mg(OH)2 and WSSe/Mg(OH)2 vdW heterostructures have thermal and dynamic stability. Besides, XSSe/Mg(OH)2 (X = Mo, W) possesses a direct bandgap with a type-I band alignment, which provides promising applications for light-emitting devices. The charge density difference was investigated, and 0.003 (or 0.0042) |e| were transferred from MoSSe (or WSSe) layer to Mg(OH)2 layer, and the potential drops were calculated to be 11.59 and 11.44 eV across the interface of the MoSSe/Mg(OH)2 and WSSe/Mg(OH)2 vdW heterostructures, respectively. Furthermore, the MoSSe/Mg(OH)2 and WSSe/Mg(OH)2 vdW heterostructures have excellent optical absorption wave. Our studies exhibit an effective method to construct new heterostructures based on Janus TMDs and develop their applications for future light emitting devices.

17.
Mol Med Rep ; 23(1)2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33236768

RESUMO

Chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) are highly prevalent potential risk factors for systemic disease. Previous studies have reported that COPD and OSA are major independent risk factors for cardio­ or cerebrovascular diseases. The present study aimed to investigate the role of bone marrow mesenchymal stem cells (BMSCs) on vascular injury in a COPD­OSA overlap syndrome (OS) rat model. Rats were randomly divided into three groups: Sham, OS model and BMSC. BMSC localization in major organs was detected via confocal laser fluorescence microscopy, and the aortic tissue pathological changes and related genes were measured using hematoxylin & eosin and Masson staining. Genes associated with vascular endothelial cell injury, including endothelin 1, vascular cell adhesion molecule 1 and endothelial nitric oxide synthase, were detected via reverse transcription­quantitative PCR and western blotting. Apoptosis of vascular endothelial cells was detected using TUNEL and immunofluorescence assays. The endothelial cell marker CD31 in injured vessels was analyzed via immunohistochemistry. BMSCs migrated into the heart, liver, spleen, lung, kidney, brain and aorta in the OS model. The green fluorescence expression of BMSCs demonstrated the highest level in the lung, followed by the aorta. Aortic tissue had a more severe vascular injury and increased apoptosis in the model group compared with the BMSC group. Vascular endothelial cell apoptosis was decreased in the BMSC group compared with the model group. The findings suggested that BMSCs could repair vascular injury by inhibiting endothelial cell damage and apoptosis. These data provide a theoretical basis for the treatment of cardiovascular diseases caused by OS with BMSCs.


Assuntos
Células da Medula Óssea/metabolismo , Transplante de Células-Tronco Mesenquimais , Doença Pulmonar Obstrutiva Crônica/terapia , Apneia Obstrutiva do Sono/terapia , Lesões do Sistema Vascular/terapia , Aloenxertos , Animais , Células da Medula Óssea/patologia , Modelos Animais de Doenças , Feminino , Células-Tronco Mesenquimais , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/patologia , Ratos , Ratos Sprague-Dawley , Apneia Obstrutiva do Sono/metabolismo , Apneia Obstrutiva do Sono/patologia , Síndrome , Lesões do Sistema Vascular/metabolismo , Lesões do Sistema Vascular/patologia
18.
Onco Targets Ther ; 13: 5395-5405, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606757

RESUMO

BACKGROUND: The tumor three-dimensional (3D) spheroid model in vitro is effective on detecting malignant cells and tumorigenesis, and assessing drug resistance. Compared with two-dimensional (2D) monolayer culture, breast cancer (BC) spheroids more accurately reflect the complex microenvironment in vivo, which have been extensively reported in BC research. MDA-MB-231 cells, the triple-negative breast cancer (TNBC) cell line, display representative epithelial to mesenchymal transition (EMT) associated with BC metastasis. However, the characterization of MDA-MB-231 spheroids has been largely unknown at present, which requires further attention. MATERIALS AND METHODS: Microwell array was conducted for the formation of MDA-MB-231 spheroids. In addition, H&E staining, immunohistochemistry (IHC), CellTiter-Glo® 3D cell viability assay, and flow cytometry were performed to investigate the structure and growth characteristics. Besides, Transwell and scratch healing assays were carried out to detect the migratory capacities compared with 2D culture. Western blotting and confocal fluorescence were selected to detect the expression of EMT-associated proteins. Additionally, the half maximal inhibitory concentration (IC50) values of antitumor compounds Carboplatin and Doxorubicin were measured to assess drug resistance. RESULTS: The MDA-MB-231 spheroids were viable, which maintained a compact structure with zonation features for up to 9 days. Moreover, those spheroids had a slower growth rate than those cultured as a monolayer and differential zones of proliferation. The migratory capacities were significantly enhanced by transferring the spheroids to 2D adherent culture. Compared with 2D culture, the levels of EMT-associated proteins were significantly up-regulated in spheroids. Furthermore, toxicity assessment showed that spheroids exhibited an increased resistance to the antitumor compounds. CONCLUSION: This study develops the simple spheroids and demonstrates their structure, growth and proliferation characteristics. According to our results, the spheroids are associated with superior EMT and high resistance to toxicological response compared with the standard 2D monocultures.

19.
J Health Psychol ; 25(3): 416-425, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-29129110

RESUMO

In this study, we investigated the mediating effect of social support on the relationship between parenting stress and life satisfaction in Chinese mothers of children with cerebral palsy (N = 369). The results showed that family support and friend support, but not significant-other support, had mediating effects on the relationship between parenting stress and life satisfaction. Moreover, the mediating effect of friend support was equal to family support. These results suggest that the focus should be on reducing parenting stress and increasing support from family and friends to help improve life satisfaction in mothers of children with cerebral palsy.


Assuntos
Paralisia Cerebral/enfermagem , Mães/psicologia , Poder Familiar/psicologia , Satisfação Pessoal , Apoio Social , Estresse Psicológico/psicologia , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino
20.
Mol Med Rep ; 20(5): 4665-4673, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31702032

RESUMO

Bone marrow­derived mesenchymal stem cells (BMSCs) possess potential therapeutic properties for treating patients with chronic obstructive pulmonary disease (COPD), which is characterized by emphysema and obstructive sleep apnea (OSA). However, their effects on overlap syndrome (OS) remain unclear. We investigated the potential therapeutic effects and possible mechanisms of BMSC transplantation in OS rats. To generate the OS model in rats, the animals underwent daily exposure to cigarette smoke and intermittent hypoxia. BMSCs were intravenously injected into rats. At 4 weeks post­transplantation, the severity of emphysema was assessed by lung hematoxylin and eosin (H&E) staining. The levels of oxidative stress and the malondialdehyde (MDA) and superoxide dismutase (SOD) contents in serum and lung were detected. The apoptosis of alveolar septal cells was also detected by TUNEL assay. Finally, we determined the expression of CD31 and VWF in lung tissues by an immunohistochemical (IHC) assay. It was found that BMSCs were able to migrate to the injured lung and aorta tissues. In lung tissues, transplanted BMSCs, some of which had differentiated into endotheliocytes, were found in the alveolar walls. The mean linear intercept (MLI) and pathological scores were higher and the mean alveolar number (MAN) was lower in the OS group than these parameters in the control group. These values were significantly reduced in the OS+BMSC group compared to those in the OS group. The MDA content was decreased and SOD activity was increased in the OS+BMSC group compared to those in the OS group. The apoptotic index of alveolar wall cells in the OS group was higher than that in the OS+BMSC group. The expression levels of CD31 and VWF in alveolar wall cells in the OS group were lower than those in the OS+BMSC group. These results indicate that BMSCs may inhibit the progression of emphysema in the OS model by differentiating into endotheliocytes and suppressing the apoptosis of endotheliocytes and oxidative stress. There is a possibility that the release of growth factors and structural support may be a determinant for the regenerative effects observed following treatment with BMSCs.


Assuntos
Células da Medula Óssea/metabolismo , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Doença Pulmonar Obstrutiva Crônica , Apneia Obstrutiva do Sono , Aloenxertos , Animais , Células da Medula Óssea/patologia , Modelos Animais de Doenças , Células-Tronco Mesenquimais/patologia , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/patologia , Doença Pulmonar Obstrutiva Crônica/terapia , Ratos , Ratos Sprague-Dawley , Apneia Obstrutiva do Sono/metabolismo , Apneia Obstrutiva do Sono/patologia , Apneia Obstrutiva do Sono/terapia
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