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1.
J Neurophysiol ; 132(1): 78-86, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691520

RESUMO

Stroke-caused synergies may result from the preferential use of the reticulospinal tract (RST) due to damage to the corticospinal tract. The RST branches multiple motoneuron pools across the arm together resulting in gross motor control or abnormal synergies, and accordingly, the controllability of individual muscles decreases. However, it is not clear whether muscles involuntarily activated by abnormal synergy vary depending on the muscles voluntarily activated when motor commands descend through the RST. Studies showed that abnormal synergies may originate from the merging and reweighting of synergies in individuals without neurological deficits. This leads to a hypothesis that those abnormal synergies are still selectively excited depending on the context. In this study, we test this hypothesis, leveraging the Fugl-Meyer assessment that could characterize the neuroanatomical architecture in individuals with a wide range of impairments. We examine the ability to perform an out-of-synergy movement with the flexion synergy caused by either shoulder or elbow loading. The results reveal that about 14% [8/57, 95% confidence interval (5.0%, 23.1%)] of the participants with severe impairment (total Fugl-Meyer score <29) in the chronic phase (6 months after stroke) are able to keep the elbow extended during shoulder loading and keep the shoulder at neutral during elbow loading. Those participants underwent a different course of neural reorganization, which enhanced abnormal synergies in comparison with individuals with mild impairment (P < 0.05). These results provide evidence that separate routes and synergy modules to motoneuron pools across the arm might exist even if the motor command is mediated possibly via the RST.NEW & NOTEWORTHY We demonstrate that abnormal synergies are still selectively excited depending on the context.


Assuntos
Músculo Esquelético , Tratos Piramidais , Acidente Vascular Cerebral , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/fisiopatologia , Músculo Esquelético/fisiologia , Músculo Esquelético/fisiopatologia , Tratos Piramidais/fisiopatologia , Tratos Piramidais/fisiologia , Idoso , Adulto , Cotovelo/fisiologia , Cotovelo/fisiopatologia , Ombro/fisiologia , Ombro/fisiopatologia
2.
J Neurophysiol ; 132(1): 87-95, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38748436

RESUMO

The flexion synergy and extension synergy are a representative consequence of a stroke and appear in the upper extremity and the lower extremity. Since the ipsilesional corticospinal tract (CST) is the most influential neural pathway for both extremities in motor execution, damage by a stroke to this tract could lead to similar motor pathological features (e.g., abnormal synergies) in both extremities. However, less attention has been paid to the interlimb correlations in the flexion synergy and extension synergy across different recovery phases of a stroke. We used results of the Fugl-Meyer assessment (FMA) to characterize those correlations in a total of 512 participants with hemiparesis after stroke from the acute phase to 1 year. The FMA provides indirect indicators of the degrees of the flexion synergy and extension synergy after stroke. We found that, generally, strong interlimb correlations (r > 0.65 with all P values < 0.0001) between the flexion synergy and extension synergy appeared in the acute-to-subacute phase (<90 days). However, the correlations of the lower-extremity extension synergy with the upper-extremity flexion synergy and extension synergy decreased (down to r = 0.38) 360 days after stroke (P < 0.05). These results suggest that the preferential use of alternative neural pathways after damage by a stroke to the CST enhances the interlimb correlations between the flexion synergy and extension synergy. At the same time, the results imply that the recovery of CST integrity or/and the fragmentation (remodeling) of the alternative neural substrates in the chronic phase may contribute to diversity in neural pathways in motor execution, eventually leading to reduced interlimb correlations.NEW & NOTEWORTHY For the first time, this article addresses the asynchronous relationships in the strengths of flexion and extension synergy expressions between the paretic upper extremity and lower extremity across various phases of stroke.


Assuntos
Extremidade Inferior , Paresia , Acidente Vascular Cerebral , Extremidade Superior , Humanos , Masculino , Acidente Vascular Cerebral/fisiopatologia , Feminino , Extremidade Superior/fisiopatologia , Pessoa de Meia-Idade , Idoso , Paresia/fisiopatologia , Paresia/etiologia , Extremidade Inferior/fisiopatologia , Tratos Piramidais/fisiopatologia , Adulto
3.
Gerodontology ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39076067

RESUMO

OBJECTIVES: To determine the dental care pattern and survival rates of participants who received long-term care (LTC) and a matched control cohort in South Korea. BACKGROUND: Global ageing trends and the development of superaged societies pose healthcare challenges. South Korea's LTC system aids those with chronic illnesses and disabilities. Despite the link between oral health and systemic diseases, providing dental care in LTC facilities often reflects social neglect. METHODS: We identified 1 459 163 individuals eligible for LTC insurance in the Korean National Health Insurance Service database from July 2008 to 2015 (LTC cohort) and 1 459 544 individuals matched through propensity-score matching (matched cohort). The LTC recipients were further categorised into subgroups based on their care type (institutional, home or mixed care). Population of utilising dental services and the average number of dental visits were counted in each cohort, and the survival rate of the LTC cohort was determined according to dental utilisation. RESULTS: Population of utilising dental services increased steadily in all cohorts except for institutional care, with the highest utilisation (around 30%) observed in the matched cohort. Lower independence in LTC cohorts was associated with lower dental utilisation: 18-27% for home care, 12-18% for mixed care, and 10% for institutional care. The survival rates in the LTC cohort were significantly lower than in the matched cohort (P < .0001), with 28.1% survival in LTC vs 59.3% in the matched cohort. CONCLUSION: Long-term care recipients experience social neglect for oral care, while higher survival rates were observed in those utilised dental services.

4.
Rev Cardiovasc Med ; 24(3): 83, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39077504

RESUMO

Background: A prehospital delay from symptom onset to hospital arrival resulted in stroke-related complications or in-hospital deaths in acute stroke patients. We aimed to investigate trends in prehospital visits as a cause of prehospital delay using data from the Korean Health Insurance Service. Methods: This nationwide, population-based, retrospective cohort study included 524,524 newly-diagnosed stroke patients admitted via the emergency departments of secondary and tertiary hospitals. We obtained the prehospital visits rate from 2010 to 2019 and identified the related characteristics. Results: Prehospital visits were observed in 111,465 patients (21.3%). The prehospital visits rate decreased from 25.1% in 2010 to 17.8% in 2019, but the number of patients increased from 11,255 cases in 2010 to 11,747 cases in 2019. Fortunately, the rate of delayed admission for more than one day decreased from 26.7% to 21.3%. However, 10.4% of patients were diagnosed more than two days later. Young, females, or patients with higher income status and living in low urbanization areas exhibited a higher rate of prehospital visits. Conclusions: Prehospital visits in Korean stroke patients decreased from 25.1% in 2010 to 17.8% in 2019. However, more than 10,000 patients still visited other medical institutions before admission to treatment.

5.
Biotechnol Bioeng ; 119(2): 566-574, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34716703

RESUMO

In vitro platforms for studying the human brain have been developed, and brain organoids derived from stem cells have been studied. However, current organoid models lack three-dimensional (3D) vascular networks, limiting organoid proliferation, differentiation, and apoptosis. In this study, we created a 3D model of vascularized spheroid cells using an injection-molded microfluidic chip. We cocultured spheroids derived from induced neural stem cells (iNSCs) with perfusable blood vessels. Gene expression analysis and immunostaining revealed that the vascular network greatly enhanced spheroid differentiation and reduced apoptosis. This platform can be used to further study the functional and structural interactions between blood vessels and neural spheroids, and ultimately to simulate brain development and disease.


Assuntos
Técnicas de Cocultura/métodos , Dispositivos Lab-On-A-Chip , Neovascularização Fisiológica/fisiologia , Células-Tronco Neurais/citologia , Esferoides Celulares/citologia , Apoptose/fisiologia , Vasos Sanguíneos/fisiologia , Diferenciação Celular/fisiologia , Humanos , Engenharia Tecidual
6.
Biotechnol Bioeng ; 119(12): 3678-3693, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36043394

RESUMO

The development of a scalable and highly reproducible in vitro tumor microenvironment (TME) platform still sheds light on new insights into cancer metastasis mechanisms and anticancer therapeutic strategies. Here, we present an all-in-one injection molded plastic array three-dimensional culture platform (All-in-One-IMPACT) that integrates vascularized tumor spheroids for highly reproducible, high-throughput experimentation. This device allows the formation of self-assembled cell spheroids on a chip by applying the hanging drop method to the cell culture channel. Then, when the hydrogel containing endothelial cells and fibroblasts is injected, the spheroid inside the droplet can be patterned together in three dimensions along the culture channel. In just two steps above, we can build a vascularized TME within a defined area. This process does not require specialized user skill and minimizes error-inducing steps, enabling both reproducibility and high throughput of the experiment. We have successfully demonstrated the process, from spheroid formation to tumor vascularization, using patient-derived cancer cells (PDCs) as well as various cancer cell lines. Furthermore, we performed combination therapies with Taxol (paclitaxel) and Avastin (bevacizumab), which are used in standard care for metastatic cancer. The All-in-One IMPACT is a powerful tool for establishing various anticancer treatment strategies through the development of a complex TME for use in high-throughput experiments.


Assuntos
Microfluídica , Neoplasias , Humanos , Células Endoteliais , Reprodutibilidade dos Testes , Esferoides Celulares , Neoplasias/tratamento farmacológico , Microambiente Tumoral
7.
Arch Womens Ment Health ; 24(1): 107-117, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32643127

RESUMO

The purpose of this study was to identify factors that influence suicidal ideation and attempts among Korean women, using longitudinal data. Data from wave 4 (n = 7227), wave 5 (n = 6892), and wave 6 (n = 6632) of the Korean Longitudinal Survey of Women and Families collected on 2012, 2014, and 2016 were subjected to Kaplan-Meier and Cox regression analysis. Number of cases for suicidal ideation was 4.7% of the total cases (n = 20,751) between wave 4 through 6; number of cases for suicidal attempts was 5.7% of the cases from suicide ideation (n = 979). Depressive feelings, bad or worst health, and increased stress had significant impacts on suicidal ideation (χ2 = 1867.84, p < .001; χ2 = 983.61, p < .001; χ2 = 884.01, p < .001) and suicidal attempts (χ2 = 5.36, p < .05; χ2 = 11.19, p < .01; χ2 = 7.46, p < .05; χ2 = 6.21, p < .05) over time, respectively. From the Cox regression analysis, non-marital status (OR = 2.50, CI = 1.40-4.48) and having more than two children (OR = 2.55, CI = 1.18-5.51) compared to not having children were identified as predictors for suicidal attempt. Although the negative effect of number of children on suicidal attempts conflicts with previous evidence, socially determined mother roles and the significance of children should be considered in culturally sensitive terms when interpreting our findings.


Assuntos
Ideação Suicida , Tentativa de Suicídio , Criança , Feminino , Humanos , Estudos Longitudinais , República da Coreia/epidemiologia , Fatores de Risco
8.
J Prosthet Dent ; 125(2): 273-278, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32336540

RESUMO

STATEMENT OF PROBLEM: Implant-supported prostheses have typically been retained by cement or screws, each of which has advantages and disadvantages. Two new types of prosthesis with complementary advantages and disadvantages have been proposed: the screw- and cement-retained prosthesis, which combines cement and screw retention, and the antiloosening inner-post screw (ALIPS) type, which uses lateral screws. Both esthetic and functional factors should be considered for anterior prostheses; however, clinical studies of the complication rates of these designs are lacking. PURPOSE: The purpose of this retrospective clinical study was to evaluate the complications of dental implant-supported restorations with various prosthetic types in the anterior region and to analyze other factors that affect complications. MATERIAL AND METHODS: This study included 51 patients who had 83 implants placed in the anterior region by a single clinician between August 2009 and December 2016. Surgical and prosthetic features were recorded, and implant complications were analyzed. RESULTS: There were 45 (55.4%) cement-retained implants, 5 (6.0%) screw- and cement-retained prosthesis implants, and 32 (38.6%) ALIPS-retained implants. Peri-implant mucositis was observed most frequently in the ALIPS type (21.9%), but the biological complications did not differ significantly with the prosthetic type. The most common mechanical complication was loss of retention in the cement type of prosthesis (30.4%) and screw loosening in the ALIPS type (43.8%). Implant complications varied with position (maxilla or mandible) and implantation timing (period from tooth extraction to implant placement). CONCLUSIONS: The complications of implants placed in the anterior region were affected by different factors but did not differ significantly with the type of the retention.


Assuntos
Implantes Dentários , Falha de Restauração Dentária , Implantes Dentários/efeitos adversos , Retenção em Prótese Dentária , Prótese Dentária Fixada por Implante/efeitos adversos , Estética Dentária , Humanos , Estudos Retrospectivos
9.
Stroke ; 51(1): 99-107, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31822247

RESUMO

Background and Purpose- The theory of cognitive reserve (CR) was introduced to account for individual differences in the clinical manifestation of neuropathology. This study investigated whether CR has a modulating effect on cognitive impairment and recovery after stroke. Methods- This study is an interim analysis of the Korean Stroke Cohort for Functioning and Rehabilitation. A total of 7459 patients with first-ever stroke were included for analysis. Education, occupation, and composite CR scores derived from those 2 variables were used as CR proxies. Scores from the Korean version of the Mini-Mental State Examination analyzed for 30 months after stroke onset were analyzed. Results- Lower CR increased the risk of cognitive impairment after stroke. The odds ratio was 1.89 (95% CI, 1.64-2.19) in patients with secondary education and 2.42 (95% CI, 2.03-2.90) in patients with primary education compared with patients with higher education. The odds ratio was 1.48 (95% CI, 1.23-1.98) in patients with a skilled manual occupation and 2.01 (95% CI, 1.42-2.83) in patients with a nonskilled manual occupation compared with patients with a managerial or professional occupation. In the multilevel model analysis, the Korean version of the Mini-Mental State Examination total score increased during the first 3 months (1.93 points per month) and then plateaued (0.02 point per month). The slopes were moderated by the level of education, occupation, and composite CR score: the higher the level of education, occupation, or CR score, the faster the recovery. In the older adult group, the Korean version of the Mini-Mental State Examination scores showed a long-term decline that was moderated by education level. Conclusions- Education and occupation can buffer an individual against cognitive impairment caused by stroke and promote rapid cognitive recovery early after stroke. In addition, higher education minimizes long-term cognitive decline after stroke, especially in older patients. Clinical Trial Registration- URL: https://www.clinicaltrials.gov. Unique identifier: NCT03402451.


Assuntos
Transtornos Cognitivos/reabilitação , Disfunção Cognitiva/reabilitação , Reserva Cognitiva/fisiologia , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cognição/fisiologia , Transtornos Cognitivos/diagnóstico , Disfunção Cognitiva/complicações , Estudos de Coortes , Feminino , Humanos , Masculino , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Acidente Vascular Cerebral/diagnóstico
10.
J Oral Implantol ; 45(2): 116-126, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30452331

RESUMO

Local delivery agents (LDAs) are widely used in peri-implantitis treatments. The aim of this study was to identify LDAs remaining on the dental implant surfaces and to analyze the components of these residues after applying various cleaning methods. Implants were prepared with a sand-blasted, large-grit, acid-etched surface. Four kinds of LDAs were applied on the implant surfaces: chlorhexidine gel (group 2), tetracycline solution (group 3), and 2 kinds of minocycline hydrochloride agents (groups 4 and 5). Group 1 received normal saline as a control. Two cleaning methods were applied for different durations as follows: (1) running distilled water for 10 seconds (subgroup A), 5 minutes (subgroup B), and 15 minutes (subgroup C); and (2) water spray of a dental-unit chair for 10 seconds (subgroup D) and 5 minutes (subgroup E). Scanning electron microscopy and energy-dispersive x-ray spectroscopy were used to analyze the surface morphology and residue components for all implants. The amount of LDA removed from the implant surfaces in groups 1, 2, 3, and 5 increased with the cleaning duration and pressure. However, Minocline remained coated on the implant surfaces in group 4 under all cleaning conditions. Minocline could not be cleaned off well by water due to its hydrophobicity. Therefore, directly using this agent on implant surfaces with peri-implantitis should be carefully considered. The presence of LDA residues without drug efficacies on implant surfaces might interfere with reosseointegration and act as a reservoir of microorganisms.


Assuntos
Anti-Infecciosos Locais , Clorexidina , Implantes Dentários , Peri-Implantite , Anti-Infecciosos Locais/administração & dosagem , Clorexidina/administração & dosagem , Humanos , Microscopia Eletrônica de Varredura , Peri-Implantite/tratamento farmacológico , Propriedades de Superfície
11.
BMC Womens Health ; 17(1): 77, 2017 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-28893226

RESUMO

BACKGROUND: The prevalence of osteoporosis associated with the aging process is anticipated to increase along with the rising aging population. Periodontitis that the most common chronic infections of humankind is considered the risk factor for osteoporosis. The aim of this study was to identify the association between osteoporosis and periodontitis using a population-based cohort. METHODS: The case group was defined as patients diagnosed with periodontitis and treated with subgingival curettage, root conditioning, periodontal flap operation, bone grafting for alveolar bone defects, and guided tissue regeneration. Case and control groups matched for gender, age, household income, type of social security, disability, and residential area were generated. A Cox proportional hazard model was constructed to examine the difference in the development of osteoporosis between the case and control groups. The final sample included 13,464 participants. RESULTS: The incidence of osteoporosis was 1.1% in males and 15.8% in females during a 10-year period. The risk factors for osteoporosis in males were increasing age and Charlson Comorbidity Index score. Periodontitis was not associated with the development of osteoporosis in males. The risk factors for osteoporosis in females were increasing age, body mass index, Charlson Comorbidity Index score, diabetes, and periodontitis. Women with periodontitis were more likely to also develop osteoporosis (HR: 1.22, 95% CI: 1.01-1.48). CONCLUSIONS: Periodontitis has an effect on the development of osteoporosis in females. Managing good teeth is required for the prevention and delay of osteoporosis. This includes dental examinations, regular cleanings and gum treatment.


Assuntos
Osteoporose/etiologia , Periodontite/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Estudos de Coortes , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Osteoporose/epidemiologia , Periodontite/epidemiologia , Modelos de Riscos Proporcionais , República da Coreia/epidemiologia , Fatores de Risco , Fatores Sexuais
12.
BMC Oral Health ; 16(1): 118, 2016 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-27814698

RESUMO

BACKGROUND: Dental insurance coverage has recently expanded in Korea. The number of patients diagnosed with periodontal disease (PD), and the actual number of periodontally compromised patients has increased. However, few studies have investigated the relationships between the prevalence of periodontal disease and the incidence of PD treatment, dental insurance policies, and socio-demographic factors. To determine the incidence of periodontal treatments required, the comprehensive longitudinal data of the National Health Insurance Service were used. This study evaluated changes in the incidence of periodontal treatments, using data from the Korean National Health Insurance Cohort Database. METHODS: A random stratified sample of 1,025,340 Korean patients was selected from National Health Insurance database, using 1,476 multistage samplings (of sex, age, and income level) for 12 years from 2002 to 2013. Chi-square analysis, and univariate, and multivariate logistic regression were used to evaluate the association of socio-demographic factors with the prevalence of PD and the incidence of periodontal treatment. RESULTS: The incidence of periodontal treatment steadily and significantly increased, in both male and female participants, from 2002 to 2013. The increase was associated with socio-demographic factors and changes in national dental insurance policies. The incidence of periodontal treatment evaluated by age is influenced by the changes in national dental policies. These results suggest that the increase in patients diagnosed with PD reflects changes in dental policies and insurance benefits. CONCLUSIONS: This study confirms that national dental policies and socio-demographic factors are related to the incidence of periodontal treatments. The incidence of periodontal treatment is significantly related to the expansion of insurance coverage in South Korea.


Assuntos
Assistência Odontológica , Doenças Periodontais/terapia , Feminino , Humanos , Incidência , Masculino , Doenças Periodontais/epidemiologia , República da Coreia/epidemiologia , Estudos Retrospectivos
13.
Emerg Infect Dis ; 21(7): 1247-50, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26079171

RESUMO

We investigated an October 2014 outbreak of illness caused by Shigella sonnei in a daycare center in the Republic of Korea (South Korea). The outbreak strain was resistant to extended-spectrum cephalosporins and fluoroquinolones and was traced to a child who had traveled to Vietnam. Improved hygiene and infection control practices are needed for prevention of shigellosis.


Assuntos
Antibacterianos/farmacologia , Ciprofloxacina/farmacologia , Surtos de Doenças , Disenteria Bacilar/tratamento farmacológico , Shigella sonnei/efeitos dos fármacos , Adolescente , Antibacterianos/uso terapêutico , Criança , Pré-Escolar , Ciprofloxacina/uso terapêutico , Farmacorresistência Bacteriana Múltipla , Disenteria Bacilar/epidemiologia , Disenteria Bacilar/microbiologia , Feminino , Genes Bacterianos , Humanos , Masculino , República da Coreia/epidemiologia , Viagem , Vietnã , Resistência beta-Lactâmica
14.
J Prosthodont ; 24(7): 517-524, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26095585

RESUMO

PURPOSE: The purpose of this retrospective study was to determine the 3-year mechanical complication rates of the most distally positioned implant-supported single crowns (ISSCs) in the posterior region, and how these complication rates are affected by several clinical factors (i.e., gender, mean age, horizontal distance [HD], position in the jaw, placement location, duration of functional loading, clinical crown-to-implant length ratio [C/I ratio], and crown height space of the implant). MATERIALS AND METHODS: The mechanical complications (i.e., abutment screw loosening [ASL], abutment screw fracture [ASF], and ceramic fracture [CF]) associated with the implants were identified by examining the patients' treatment records, clinical photographs, and intraoral periapical radiographs. Statistical analyses were performed using chi-square and Student's t-test to identify the relationship between various clinical factors and the mechanical complication rates. Receiver operating characteristics analysis was conducted to determine the optimal cut-off value for the HD between the most distally positioned ISSCs and the mesially adjacent natural tooth beyond which complications occur. RESULTS: The study inclusion criteria were met by 183 patients who had undergone implant surgery in the period 2004 to 2011, involving a total of 221 implant treatments. Mechanical complications were present in 40 (18.1%) of the 221 investigated ISSCs. ASL was the most common complication (n = 28, 12.7%), followed in order by CF (n = 9, 4.1%) and ASF (n = 3, 1.4%). Repeated ASL and CF occurred in four (1.8%) and two (0.9%) implants, respectively. The mechanical complication rates differed significantly between implants with different HDs (p = 0.009) and clinical C/I ratios (p = 0.019); however, there was no significant association between the other clinical factors and the mechanical complication rates. CONCLUSION: Within the limitations of this study, it appears that the incidence of mechanical complications is higher for the most distally positioned ISSCs in the posterior region than for those positioned at other sites. Furthermore, since the rate of mechanical complications increases with increasing HD, an HD of 3.7 mm or less is recommended.

15.
ScientificWorldJournal ; 2014: 954174, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25254260

RESUMO

This study presents wave height distribution in terms of stem wave evolution phenomena on partially perforated wall structures through three-dimensional laboratory experiments. The plain and partially perforated walls were tested to understand their effects on the stem wave evolution under the monochromatic and random wave cases with the various wave conditions, incident angle (from 10 to 40 degrees), and configurations of front and side walls. The partially perforated wall reduced the relative wave heights more effectively compared to the plain wall structure. Partially perforated walls with side walls showed a better performance in terms of wave height reduction compared to the structure without the side wall. Moreover, the relative wave heights along the wall were relatively small when the relative chamber width is large, within the range of the chamber width in this study. The wave spectra showed a frequency dependency of the wave energy dissipation. In most cases, the existence of side wall is a more important factor than the porosity of the front wall in terms of the wave height reduction even if the partially perforated wall was still effective compared to the plain wall.


Assuntos
Praias , Simulação por Computador , Modelos Teóricos , Movimentos da Água , Indústria da Construção/métodos , Materiais de Construção/normas , Desastres/prevenção & controle , Oceanos e Mares , Reprodutibilidade dos Testes , Fatores de Risco
16.
ScientificWorldJournal ; 2014: 570325, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25276853

RESUMO

Fringing reefs play an important role in protecting the coastal area by inducing wave breaking and wave energy dissipation. However, modeling of wave transformation and energy dissipation on this topography is still difficult due to the unique structure. In the present study, two-dimensional laboratory experiments were conducted to investigate the cross-shore variations of wave transformation, setup, and breaking phenomena over an idealized fringing reef with the 1/40 reef slope and to verify the Boussinesq model under monochromatic wave conditions. One-layer and two-layer model configurations of the Boussinesq model were used to figure out the model capability. Both models predicted well (r (2) > 0.8) the cross-shore variation of the wave heights, crests, troughs, and setups when the nonlinearity is not too high (A 0/h 0 < 0.07 in this study). However, as the wave nonlinearity and steepness increase, the one-layer model showed problems in prediction and stability due to the error on the vertical profile of fluid velocity. The results in this study revealed that one-layer model is not suitable in the highly nonlinear wave condition over a fringing reef bathymetry. This data set can contribute to the numerical model verification.


Assuntos
Algoritmos , Antozoários/fisiologia , Recifes de Corais , Modelos Teóricos , Movimentos da Água , Animais , Conservação dos Recursos Naturais , Hidrodinâmica , Oceanos e Mares , Água do Mar
17.
Sci Rep ; 14(1): 12606, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824187

RESUMO

Most artificial intelligence (AI) studies have attempted to identify dental implant systems (DISs) while excluding low-quality and distorted dental radiographs, limiting their actual clinical use. This study aimed to evaluate the effectiveness of an AI model, trained on a large and multi-center dataset, in identifying different types of DIS in low-quality and distorted dental radiographs. Based on the fine-tuned pre-trained ResNet-50 algorithm, 156,965 panoramic and periapical radiological images were used as training and validation datasets, and 530 low-quality and distorted images of four types (including those not perpendicular to the axis of the fixture, radiation overexposure, cut off the apex of the fixture, and containing foreign bodies) were used as test datasets. Moreover, the accuracy performance of low-quality and distorted DIS classification was compared using AI and five periodontists. Based on a test dataset, the performance evaluation of the AI model achieved accuracy, precision, recall, and F1 score metrics of 95.05%, 95.91%, 92.49%, and 94.17%, respectively. However, five periodontists performed the classification of nine types of DISs based on four different types of low-quality and distorted radiographs, achieving a mean overall accuracy of 37.2 ± 29.0%. Within the limitations of this study, AI demonstrated superior accuracy in identifying DIS from low-quality or distorted radiographs, outperforming dental professionals in classification tasks. However, for actual clinical application of AI, extensive standardization research on low-quality and distorted radiographic images is essential.


Assuntos
Inteligência Artificial , Implantes Dentários , Radiografia Dentária , Humanos , Radiografia Dentária/métodos , Algoritmos , Radiografia Panorâmica/métodos
18.
medRxiv ; 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38370652

RESUMO

Objective: The flexion synergy and extension synergy are a representative consequence of a stroke and appear in the upper extremity and lower extremity. Since the ipsilesional corticospinal tract (CST) is the most influential neural pathway for both extremities in motor execution, damage by a stroke to this tract could lead to similar motor pathological features (e.g., abnormal synergies) in both extremities. However less attention has been paid to the inter-limb correlations in the flexion synergy and extension synergy across different recovery phases of a stroke. Methods: In this study, we used results of the Fugl-Meyer assessment (FMA) to characterize those correlations in a total of 512 participants with hemiparesis post stroke from the acute phase to 1 year. The FMA provides indirect indicators of the degrees of the flexion synergy and extension synergy post stroke. Results: We found that generally, strong inter-limb correlations (r>0.65 with all p-values<0.0001) between the flexion synergy and extension synergy appeared in the acute-to-subacute phase (<90 days). But correlations of lower-extremity extension synergy with upper-extremity flexion synergy and extension synergy decreased (down to r=0.38) around 360 days after stroke (p<0.05). Interpretation: These results suggest that the preferential use of alternative neural pathways after damage by a stroke to the CST enhances inter-limb correlations between the flexion synergy and extension, however a recovery of the CST or/and the functional fragmentation (remodeling) of the alternative neural substrates in the chronic phase contribute to diversity in neural pathways in motor execution, eventually leading to reduced inter-limb correlations.

19.
Lab Chip ; 24(4): 751-763, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38193617

RESUMO

Despite significant advancements in three-dimensional (3D) cell culture technology and the acquisition of extensive data, there is an ongoing need for more effective and dependable data analysis methods. These concerns arise from the continued reliance on manual quantification techniques. In this study, we introduce a microphysiological system (MPS) that seamlessly integrates 3D cell culture to acquire large-scale imaging data and employs deep learning-based virtual staining for quantitative angiogenesis analysis. We utilize a standardized microfluidic device to obtain comprehensive angiogenesis data. Introducing Angio-Net, a novel solution that replaces conventional immunocytochemistry, we convert brightfield images into label-free virtual fluorescence images through the fusion of SegNet and cGAN. Moreover, we develop a tool capable of extracting morphological blood vessel features and automating their measurement, facilitating precise quantitative analysis. This integrated system proves to be invaluable for evaluating drug efficacy, including the assessment of anticancer drugs on targets such as the tumor microenvironment. Additionally, its unique ability to enable live cell imaging without the need for cell fixation promises to broaden the horizons of pharmaceutical and biological research. Our study pioneers a powerful approach to high-throughput angiogenesis analysis, marking a significant advancement in MPS.


Assuntos
Angiogênese , Aprendizado Profundo , Técnicas de Cultura de Células
20.
Front Immunol ; 15: 1336246, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38515751

RESUMO

Introduction: To understand the immune system within the tumor microenvironment (TME) of non-small cell lung cancer (NSCLC), it is crucial to elucidate the characteristics of molecules associated with T cell activation. Methods: We conducted an in-depth analysis using single-cell RNA sequencing data obtained from tissue samples of 19 NSCLC patients. T cells were classified based on the Tumor Proportion Score (TPS) within the tumor region, and molecular markers associated with activation and exhaustion were analyzed in T cells from high TPS areas. Results: Notably, tetraspanins CD81 and CD82, belonging to the tetraspanin protein family, were found to be expressed in activated T cells, particularly in cytotoxic T cells. These tetraspanins showed strong correlations with activation and exhaustion markers. In vitro experiments confirmed increased expression of CD81 and CD82 in IL-2-stimulated T cells. T cells were categorized into CD81highCD82high and CD81lowCD82low groups based on their expression levels, with CD81highCD82high T cells exhibiting elevated activation markers such as CD25 and CD69 compared to CD81lowCD82low T cells. This trend was consistent across CD3+, CD8+, and CD4+ T cell subsets. Moreover, CD81highCD82high T cells, when stimulated with anti-CD3, demonstrated enhanced secretion of cytokines such as IFN-γ, TNF-α, and IL-2, along with an increase in the proportion of memory T cells. Bulk RNA sequencing results after sorting CD81highCD82high and CD81lowCD82low T cells consistently supported the roles of CD81 and CD82. Experiments with overexpressed CD81 and CD82 showed increased cytotoxicity against target cells. Discussion: These findings highlight the multifaceted roles of CD81 and CD82 in T cell activation, cytokine production, memory subset accumulation, and target cell cytolysis. Therefore, these findings suggest the potential of CD81 and CD82 as promising candidates for co-stimulatory molecules in immune therapeutic strategies for cancer treatment within the intricate TME.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Antígenos CD/metabolismo , Linfócitos do Interstício Tumoral , Interleucina-2/metabolismo , Microambiente Tumoral , Neoplasias Pulmonares/metabolismo , Citocinas/metabolismo , Tetraspaninas/metabolismo , Tetraspanina 28 , Proteína Kangai-1/metabolismo
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