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1.
ACS Appl Mater Interfaces ; 15(50): 58605-58612, 2023 Dec 20.
Article in English | MEDLINE | ID: mdl-38051158

ABSTRACT

The inherent interlayer resistance in two-dimensional (2D) van der Waals (vdW) multilayers is expected to significantly influence the carrier density profile along the thickness, provoking spatial modification and separation of the conducting channel inside the multilayers, in conjunction with the thickness-dependent carrier mobility. However, the effect of the interlayer resistance on the variation in the carrier density profile and its direction along the thickness under different electrostatic bias conditions has been elusive. Here, we reveal the presence of a negative differential interlayer resistance (NDIR) in WSe2 multilayers by considering various contact electrode configurations: (i) bottom contact, (ii) top contact, and (iii) vertical double-side contact (VDC). The contact-structure-dependent shape modification of the transconductance clearly manifests the redistribution of carrier density and indicates the direction of the conducting channel migration along the thickness. Furthermore, the distinct characteristic of the electrically tunable NDIR in 2D WSe2 multilayers is revealed by the observed discrepancy between the top- and bottom-channel resistances determined by four-probe measurements with VDC. Our results provide an optimized device layout and further insights into the distinct carrier transport mechanism in 2D vdW multilayers.

2.
Gerontol Geriatr Med ; 9: 23337214231201204, 2023.
Article in English | MEDLINE | ID: mdl-37781643

ABSTRACT

Social isolation is a well-documented contributor to poor mental and physical health, and interventions promoting social connectedness have been associated with various health benefits. This study examined predictors of participation in a telephone-based social connectedness intervention for socially isolated older adults. Data were obtained from a social-connectedness intervention that paired college students with Houston-area, community-dwelling adults aged 65 years and older and enrolled in Medicare Advantage plans. We combined machine learning and regression techniques to identify significant predictors of program participation. The following machine-learning methods were implemented: (1) k-nearest neighbors, (2) decision tree and ensembles of decision trees, (3) gradient-boosted decision tree, and (4) random forest. The primary outcome was a binary flag indicating participation in the telephone-based social-connectedness intervention. The most predictive variables in the ML models, with scores corresponding to the 90th percentile or greater, were included in the regression analysis. The predictive ability of each model showed high discriminative power, with test accuracies greater than 95%. Our findings suggest that telephone-based social-connectedness interventions appeal to individuals with disabilities, depression, arthritis, and higher risk scores. scores. Recognizing features that predict participation in social-connectedness programs is the first step to increasing reach and fostering patient engagement.

3.
ACS Appl Mater Interfaces ; 15(19): 23439-23446, 2023 May 17.
Article in English | MEDLINE | ID: mdl-37133360

ABSTRACT

Two-dimensional (2D) van der Waals (vdW) layered materials have provided novel opportunities to explore interesting physical properties such as thickness-dependent bandgap, moiré excitons, superconductivity, and superfluidity. However, the presence of interlayer resistance along the thickness and Schottky barrier in metal-to-2D vdW semiconducting materials causes a limited interlayer charge injection efficiency, perturbing various intrinsic properties of 2D vdW multilayers. Herein, we report a simple but powerful contact electrode design to enhance interlayer carrier injection efficiency along the thickness by constructing vertical double-side contact (VDC) electrodes. A 2-fold extended contact area of VDC not only strongly limits an interlayer resistance contribution to the field-effect mobility and current density at the metal-to-2D semiconductor interface but also significantly suppresses both current transfer length (≤1 µm) and specific contact resistivity (≤1 mΩ·cm2), manifesting clear benefits of VDC in comparison with those in conventional top-contact and bottom-contact configurations. Our layout for contact electrode configuration may suggest an advanced electronic device platform for high-performing 2D optoelectronic devices.

4.
Am J Disaster Med ; 17(2): 117-125, 2022.
Article in English | MEDLINE | ID: mdl-36494882

ABSTRACT

OBJECTIVE: Evidence suggests that people of color, especially African Americans and non-White Hispanics, residing in low-income communities are the most vulnerable to natural disasters. This study assessed individual level of self-perceived disaster preparedness, disaster response actions, and sociodemographic predictors of disaster preparedness among older minority adults in Houston, Texas. METHOD: Working with Houston-area community-based organizations and senior-living centers, a cross-sectional survey, available in English and Spanish, was disseminated between November 2020 and January 2021. PARTICIPANTS: Five hundred and twenty-two older minority adults aged 55+ completed the electronic survey. MAIN OUTCOME MEASURE(S): The main outcome measure was the level of self-perceived preparedness regarding emergencies and disastersie, prepared vs not prepared-among the study participants. RESULTS: Overall, about 58 percent of older minority adults did not perceive themselves to be prepared. Compared to individuals reporting annual incomes below $25,000, individuals reporting annual incomes between $25,000 and $74,999 were more likely to report being prepared [odds ratio (OR) = 2.28, 95 percent confidence interval (CI) = 1.29, 4.05]. Individuals who tested positive or had a close family member test positive for COVID-19 experienced 2.16 times higher odds of having self-perceived disaster preparedness than those who did not [OR = 2.16, 95 percent CI = 1.37, 3.42]. None of the other covariates were statistically significant. CONCLUSIONS: While we observed no differences in self-perceived disaster preparedness between African American and Hispanic older adults, our findings suggest the importance of prior experience/exposure to previous disasters and the role of socioeconomic status in self-perceived disaster preparedness in minority older adults.


Subject(s)
COVID-19 , Disaster Planning , Disasters , Humans , Aged , Cross-Sectional Studies , Surveys and Questionnaires
5.
Nanomaterials (Basel) ; 12(20)2022 Oct 11.
Article in English | MEDLINE | ID: mdl-36296738

ABSTRACT

While graphene shows great potential for diverse device applications, to broaden the scope of graphene-based device applications further, it would be necessary to tune the electronic state of graphene and its resultant electrical properties properly. Surface decoration with metal nanoparticles is one of the efficient doping methods to control the properties of two-dimensional materials. Here, we report the p-type doping effects in single-layer graphene decorated with silver nanoparticles (AgNPs) that were formed area-selectively by the facile one-step photoreduction (PR) process based on focused-laser irradiation. During the PR process, AgNPs were reduced on graphene in AgNO3 solution by laser-driven photoexcitation followed by chemical reactions. Based on scanning electron microscopy analyses, the morphology characteristics of AgNPs were shown to be modulated by the laser dwell time and power controllably. Further, p-type doping effects were demonstrated using graphene-field-effect transistor structures whose graphene channels were selectively decorated with AgNPs by the PR process, as validated by the decrease in channel resistance and the shift of the Dirac point voltage. Moreover, the growth of AgNPs was observed to be more active on the graphene channel that was laser-annealed ahead of the PR process, leading to enhancing the efficiency of this approach for altering device characteristics.

6.
J Am Coll Health ; : 1-7, 2022 Aug 18.
Article in English | MEDLINE | ID: mdl-35981316

ABSTRACT

OBJECTIVES: To describe the participants of a university-based COVID-19 contact tracing course and determine whether the course changed knowledge, attitudes, and intention to participate in contact tracing. PARTICIPANTS: Faculty, staff, and students were eligible. METHODS: Surveys evaluated the impact of the course on participant intentions to engage in contact tracing. Logistic regression identified characteristics associated with increased likelihood of participating in contact tracing. RESULTS: Nearly 800 individuals participated, of whom 26.2% identified as Hispanic/Latino and 14.0% as Black. Nearly half (48.8%) planned to conduct contact tracing. While attitudes did not change, knowledge improved (67.9% vs. 93.8% scores on assessments; p < 0.001). Younger participants and Black individuals were more more likely to be confident that they would participate in contact tracing. CONCLUSIONS: Course completion was associated with increased knowledge. Participants were racially and ethnically diverse, highlighting how universities can partner with health departments to develop workforces that reflect local communities.

7.
J Am Board Fam Med ; 35(3): 457-464, 2022.
Article in English | MEDLINE | ID: mdl-35641037

ABSTRACT

INTRODUCTION: Increased telemedicine implementation may promote primary care access. However, gaps in telemedicine uptake may perpetuate existing disparities in primary care access. This study assessed provider- and patient-level factors associated with telemedicine use in community-based family practice clinics. METHODS: This retrospective study used electronic medical records data from a large Federally Qualified Health Center. A 3-level mixed-effects logistic regression model explored predictors of telemedicine use, with provider and patient as random effects. RESULTS: The analytic sample included 37,428 unique patients with 106,567 primary care encounters with 42 family medicine providers. Fifty-seven percent of the sample identified as Hispanic, 28% non-Hispanic White, and 11% non-Hispanic Black. Compared to Hispanics, non-Hispanic White patients had 61% higher odds of a telemedicine visit, and non-Hispanic Black patients had 32% higher odds of a telemedicine visit. The odds of telemedicine use were lower for those who were uninsured. Those residing in metropolitan areas or medically underserved areas had greater odds of a telemedicine appointment. Commute time exhibited a dose-response relationship with telemedicine use. Provider characteristics were not significantly associated with telemedicine use. DISCUSSION: While provider characteristics were not associated with telemedicine use, greater focus on patient characteristics specific to the population served is necessary.


Subject(s)
Family Practice , Telemedicine , Ambulatory Care Facilities , Humans , Retrospective Studies
8.
J Gen Intern Med ; 37(5): 1191-1197, 2022 04.
Article in English | MEDLINE | ID: mdl-35112280

ABSTRACT

BACKGROUND: The Coronavirus Aid, Relief, and Economic Security (CARES) Act led to the rapid implementation of telemedicine across healthcare office settings. This innovation has the potential to improve healthcare use and ensure continuity of care. However, this delivery model could have an unintended consequence of worsening racial/ethnic disparities in healthcare utilization if adoption varies across sub-populations. OBJECTIVE: To examine associations between telemedicine use and race/ethnicity between 3/1/2020 and 11/30/2020, and the influence of other individual- and geographical-level factors on this relationship. DESIGN: Cohort study PARTICIPANTS: EMR data from 55 clinics in a FQHC network MAIN MEASURES: The dependent variable was visit type (in-person vs. telemedicine). Predictors of interest were patient race and ethnicity. To account for repeated visits within each patient nested within clinic, a three-level, mixed-effects, multivariable, logistic regression model was used. Subgroup analyses examined correlates of telemedicine use in African American and Hispanic cohorts, separately. KEY RESULTS: The analytic sample included 233,302 visits for 67,733 unique patients. African Americans (OR = 0.65, 95% CI: 0.61, 0.69), Asians (OR = 0.58, 95% CI: 0.52, 0.65), and American Indians / Alaska Natives and other Pacific Islanders (OR = 0.82, 95% CI: 0.70, 0.98) were significantly less likely to use telemedicine compared to Whites. Hispanics were also less likely to have a telemedicine visit (OR = 0.49, 95% CI: 0.47, 0.51) compared to non-Hispanics. Nonacute visits were more likely to be conducted via telemedicine. Distance to clinic exhibited a dose-response relationship such that patients who lived farthest from the clinics were most likely to have telemedicine visits. In the subgroup analyses to examine predictors of telemedicine use, the dose-response relationship between distance from clinic and telemedicine use persisted, with increasing distance associated with increasing likelihood of telemedicine use, in both African American and Hispanic cohorts. Nonacute visits were associated with telemedicine use in the Hispanic cohort, but not in the Black / African American cohort. CONCLUSION: Racial/ethnic disparities in telemedicine use persisted among this cohort. However, telemedicine improved utilization for African Americans and Hispanics living farther away from the clinic.


Subject(s)
COVID-19 , Telemedicine , COVID-19/epidemiology , Ethnicity , Healthcare Disparities , Humans , Pandemics , Racial Groups
9.
Article in English | MEDLINE | ID: mdl-36612723

ABSTRACT

By 2050, one in five Americans will be 65 years and older. The growing proportion of older adults in the U.S. population has implications for many aspects of health including disaster preparedness. This study assessed correlates of disaster preparedness among community-dwelling minority older adults and explored unique differences for African American and Hispanic older adults. An electronic survey was disseminated to older minority adults 55+, between November 2020 and January 2021 (n = 522). An empirical framework was used to contextualize 12 disaster-related activities into survival an0000000d planning actions. Multivariate logistic regression models were stratified by race/ethnicity to examine the correlates of survival and planning actions in African American and Hispanic older adults, separately. We found that approximately 6 in 10 older minority adults did not perceive themselves to be disaster prepared. Medicare coverage was positively associated with survival and planning actions. Income level and prior experience with disaster were related to survival actions in the African American population. In conclusion, recognizing the gaps in disaster-preparedness in elderly minority communities can inform culturally sensitive interventions to improve disaster preparedness and recovery.


Subject(s)
Disaster Planning , Disasters , Humans , Aged , United States , Medicare , Surveys and Questionnaires , Logistic Models
10.
Ann Med ; 54(1): 98-107, 2022 12.
Article in English | MEDLINE | ID: mdl-34969330

ABSTRACT

BACKGROUND AND OBJECTIVE: The Coronavirus Aid, Relief, and Economic Security Act led to the rapid implementation of telemedicine across health care office settings. Whether this transition to telemedicine has any impact on missed appointments is yet to be determined. This study examined the relationship between telemedicine usage and missed appointments during the COVID-19 pandemic. METHOD: This retrospective study used appointment-level data from 55 Federally Qualified Health Centre clinics in Texas between March and November 2020. To account for the nested data structure of repeated appointments within each patient, a mixed-effects multivariable logistic regression model was used to examine associations between telemedicine use and missed appointments, adjusting for patient sociodemographic characteristics, geographic classification, past medical history, and clinic characteristics. The independent variable was having a telemedicine appointment, defined as an audiovisual consultation started and finalized via a telemedicine platform. The outcome of interest was having a missed appointment (yes/no) after a scheduled and confirmed medical appointment. Results from this initial model were stratified by appointment type (in-person vs. telemedicine). RESULTS: The analytic sample included 278,171 appointments for 85,413 unique patients. The overall missed appointment rate was 18%, and 25% of all appointments were telemedicine appointments. Compared to in-person visits, telemedicine visits were less likely to result in a missed appointment (OR = 0.87, p < .001). Compared to Whites, Asians were less likely to have a missed appointment (OR = 0.82, p < .001) while African Americans, Hispanics, and American Indians were all significantly more likely to have missed appointments (OR = 1.61, p < .001; OR = 1.19, p = .01; OR = 1.22, p < .01, respectively). Those accessing mental health services (OR = 1.57 for in-person and 0.78 for telemedicine) and living in metropolitan areas (OR = 1.15 for in-person and 0.82 for telemedicine) were more likely to miss in-person appointments but less likely to miss telemedicine appointments. Patients with frequent medical visits or those living with chronic diseases were more likely to miss in-person appointments but less likely to miss telemedicine appointments. CONCLUSIONS: Telemedicine is strongly associated with fewer missed appointments. Although our findings suggest a residual lag in minority populations, specific patient populations, including those with frequent prior visits or chronic conditions, those seeking mental health services, and those living in metropolitan areas were less likely to miss telemedicine appointments than in-person visits. These findings highlight how telemedicine can enable effective and accessible care by reducing missed healthcare appointments.KEY MESSAGESTelemedicine was associated with 13% lower odds of missed appointments.Patients with frequent medical visits or those living with chronic diseases were less likely to miss telemedicine appointments but more likely to miss in-person appointments.Patients seeking mental health services were less likely to miss telemedicine appointments but more likely to miss in-person appointments.Similarly, those living in metropolitan areas were less likely to miss telemedicine appointments but more likely to miss in-person appointments.


Subject(s)
Appointments and Schedules , COVID-19 , Community Health Centers , Pandemics , Telemedicine , COVID-19/epidemiology , Humans , Retrospective Studies , Telemedicine/organization & administration
11.
Front Public Health ; 9: 702965, 2021.
Article in English | MEDLINE | ID: mdl-34956998

ABSTRACT

Background: The past year has severely curtailed social interactions among older adults given their high rates of COVID-19 morbidity and mortality. This study examined social, behavioral, and medical correlates of social isolation among community-dwelling older adults during the COVID-19 pandemic and stratified findings to explore unique differences in two typically neglected populations, African American and Hispanic older adults. Methods: Working with community-based organizations and senior living centers, the research team administered a survey to older adults 55 years of age and older (n = 575). The survey assessed COVID-19 prevention behaviors, medical conditions, and lived experiences, including feelings of social isolation, in the target population. Responses to a previously validated social isolation question informed a dichotomous social isolation dependent variable. Multivariable logistic regression was used to adjust for sociodemographic characteristics, medical conditions, unmet caregiving needs, and COVID-19 prevention behaviors. Results from the regression model were stratified by race/ethnicity to examine correlates of social isolation in African American and Hispanic older adults, separately. Results: Overall, female sex and a higher level of education were also positively associated with social isolation (OR = 2.46, p = 0.04; OR = 5.49, p = 0.02) while having insurance exhibited an inverse relationship (OR = 0.25, p = 0.03). Unmet caregiving needs were strongly associated with social isolation (OR = 6.41, p < 0.001) as was having any chronic conditions (OR = 2.99, p = 0.02). Diabetes was the single strongest chronic condition predictor of social isolation. Among minority older adults, a different pattern emerged. For Hispanic older adults, language, unmet caregiving needs, and social distancing were strongly associated with social isolation; while unmet caregiving needs, having 1+ chronic conditions and adhering to social distancing guidelines were significant predictors in African American older adults. Conclusion: These findings suggest that social isolation affects older adults in a myriad of ways and support the need for culturally sensitive initiatives to mitigate the effect of social isolation in these vulnerable populations.


Subject(s)
COVID-19 , Aged , Female , Humans , Independent Living , Pandemics , SARS-CoV-2 , Social Isolation
12.
South Med J ; 114(9): 593-596, 2021 09.
Article in English | MEDLINE | ID: mdl-34480193

ABSTRACT

OBJECTIVES: Since the onset of the coronavirus disease 2019 (COVID-19) pandemic, many US clinics have shifted some or all of their practice from in-person to virtual visits. In this study, we assessed the use of telehealth among primary care and specialty clinics, by targeting healthcare administrators via multiple channels. METHODS: Using an online survey, we assessed the use of, barriers to, and reimbursement for telehealth. Respondents included clinic administrators (chief executive officers, vice presidents, directors, and senior-level managers). RESULTS: A total of 85 complete responses were recorded, 79% of which represented solo or group practices and 63% reported a daily patient census >50. The proportion of clinics that delivered ≥50% of their consults using telehealth increased from 16% in March to 42% in April, 35% in May, and 30% in June. Clinics identified problems with telehealth reimbursement; although 63% of clinics reported that ≥75% of their telehealth consults were reimbursed, only 51% indicated that ≥75% of their telehealth visits were reimbursed at par with in-person office visits. Sixty-five percent of clinics reported having basic or foundational telehealth services, whereas only 9% of clinics reported advanced telehealth maturity. Value-based care participating clinics were more likely to report advanced telehealth services (27%), compared with non-value-based care clinics (3%). CONCLUSIONS: These findings highlight the adaptability of clinics to quickly transition and adopt telehealth. Uncertainty about reimbursement and policy changes may make the shift temporal, however.


Subject(s)
COVID-19/prevention & control , Medicine/statistics & numerical data , Mental Health Services/statistics & numerical data , Primary Health Care/statistics & numerical data , Telemedicine/statistics & numerical data , Health Care Surveys , Humans , Medicine/methods , Primary Health Care/methods , SARS-CoV-2 , Telemedicine/methods , Texas
13.
J Health Care Poor Underserved ; 32(2): 948-957, 2021.
Article in English | MEDLINE | ID: mdl-34120986

ABSTRACT

The COVID-19 pandemic has dramatically altered the landscape of health care delivery, prompting a rapid, widespread adoption of telehealth in primary care practices. Using a pooled sample of 1,344 primary care clinics in Texas, we examined the adoption of telehealth in Texas during the initial months of the COVID-19 pandemic, by comparing medically underserved area (MUA) clinics and non-medically underserved area (non-MUA) clinics. Our analysis suggests that compared with MUA clinics, clinics in non-MUAs were more likely to conduct a majority of their visits via telehealth before May 1st, 2020. However, later surveys indicated that differences in telehealth use between MUA and non-MUA clinics lessened, suggesting that some of the barriers that MUA clinics initially faced might have resolved over time. This research provides an additional perspective in discussions about telehealth adoption on a widespread, permanent basis in Texas and the U.S.


Subject(s)
Ambulatory Care Facilities/statistics & numerical data , COVID-19/epidemiology , Healthcare Disparities , Primary Health Care , Telemedicine/statistics & numerical data , Health Services Needs and Demand , Humans , Medically Underserved Area , Pandemics , Texas/epidemiology
14.
Article in English | MEDLINE | ID: mdl-35010293

ABSTRACT

Although evidence suggests that successive climate disasters are on the rise, few studies have documented the disproportionate impacts on communities of color. Through the unique lens of successive disaster events (Hurricane Harvey and Winter Storm Uri) coupled with the COVID-19 pandemic, we assessed disaster exposure in minority communities in Harris County, Texas. A mixed methods approach employing qualitative and quantitative designs was used to examine the relationships between successive disasters (and the role of climate change), population geography, race, and health disparities-related outcomes. This study identified four communities in the greater Houston area with predominantly non-Hispanic African American residents. We used data chronicling the local community and environment to build base maps and conducted spatial analyses using Geographic Information System (GIS) mapping. We complemented these data with focus groups to assess participants' experiences in disaster planning and recovery, as well as community resilience. Thematic analysis was used to identify key patterns. Across all four communities, we observed significant Hurricane Harvey flooding and significantly greater exposure to 10 of the 11 COVID-19 risk factors examined, compared to the rest of the county. Spatial analyses reveal higher disease burden, greater social vulnerability, and significantly higher community-level risk factors for both pandemics and disaster events in the four communities, compared to all other communities in Harris County. Two themes emerged from thematic data analysis: (1) Prior disaster exposure prepared minority populations in Harris County to better handle subsequent disaster suggesting enhanced disaster resilience, and (2) social connectedness was key to disaster resiliency. Long-standing disparities make people of color at greater risk for social vulnerability. Addressing climate change offers the potential to alleviate these health disparities.


Subject(s)
COVID-19 , Cyclonic Storms , Disaster Planning , Disasters , Climate Change , Humans , Pandemics , SARS-CoV-2 , Social Vulnerability , Texas
15.
Ann Rehabil Med ; 43(3): 335-340, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31311256

ABSTRACT

Deep brain stimulation (DBS) in internal globus pallidus is considered to be a good option for controlling generalized dystonia in patients with this condition. In this relation, it is known that DBS has already been shown to have significant effects on primary dystonia, but is seen as controversial in secondary dystonia including cerebral palsy (CP). On the other hand, intrathecal baclofen (ITB) has been known to reduce spasticity and dystonia in patients who did not respond to oral medications or botulinum toxin treatment. Here, we report a patient with dystonic CP, who received the ITB pump implantation long after the DBS and who noted remarkable improvement in the 36-Item Short Form Health Survey, Dystonia Rating Scale, Modified Barthel Index, and visual analog scale scores for pain after an ITB pump implantation was used as compared with DBS. To our knowledge, the present case report is the first to demonstrate the effects of an ITB pump on reducing pain and dystonia and improving quality of life and satisfaction, compared with DBS in a patient with CP.

16.
Front Neurol ; 9: 465, 2018.
Article in English | MEDLINE | ID: mdl-30061854

ABSTRACT

Environmental enrichment (EE) is a therapeutic paradigm that consists of complex combinations of physical, cognitive, and social stimuli. The mechanisms underlying EE-mediated synaptic plasticity have yet to be fully elucidated. In this study, we investigated the effects of EE on synaptic vesicle-associated proteins and whether the expression of these proteins is related to behavioral outcomes. A total of 44 CD-1® (ICR) mice aged 6 weeks were randomly assigned to either standard cages or EE (N = 22 each). Rotarod and ladder walking tests were then performed to evaluate motor function. To identify the molecular mechanisms underlying the effects of EE, we assessed differentially expressed proteins (DEPs) in the striatum by proteomic analysis. Quantitative real-time polymerase chain reaction (qRT-PCR), western blot, and immunohistochemistry were conducted to validate the expressions of these proteins. In the behavioral assessment, EE significantly enhanced performance on the rotarod and ladder walking tests. A total of 116 DEPs (54 upregulated and 62 downregulated proteins) were identified in mice exposed to EE. Gene ontology (GO) analysis demonstrated that the upregulated proteins in EE mice were primarily related to biological processes of synaptic vesicle transport and exocytosis. The GO terms for these biological processes commonly included Synaptic vesicle glycoprotein 2B (SV2B), Rabphilin-3A, and Piccolo. The qRT-PCR and western blot analyses revealed that EE increased the expression of SV2B, Rabphilin-3A and Piccolo in the striatum compared to the control group. Immunohistochemistry showed that the density of Piccolo in the vicinity of the subventricular zone was significantly increased in the EE mice compared with control mice. In conclusion, EE upregulates proteins associated with synaptic vesicle transport and exocytosis such as SV2B, Rabphilin-3A and Piccolo in the striatum. These upregulated proteins may be responsible for locomotor performance improvement, as shown in rotarod and ladder walking tests. Elucidation of these changes in synaptic protein expression provides new insights into the mechanism and potential role of EE.

17.
Ann Rehabil Med ; 42(3): 425-432, 2018 Jun 27.
Article in English | MEDLINE | ID: mdl-29961740

ABSTRACT

OBJECTIVE: To identify the relationship between maximum phonation time (MPT) and swallowing function, as well as the elements of swallowing, in order to provide a rationale for speech therapy in patients with Parkinsonism manifesting dysphagia. METHODS: Thirty patients with Parkinsonism who underwent speech evaluation and videofluoroscopic swallowing study (VFSS) were recruited. The MPT, the longest periods of sustained pronunciation of /aa/, was evaluated. The VFSS was evaluated using Penetration Aspiration Scale (PAS), National Institutes of Health-Swallowing Safety Scale (NIH-SSS), and Videofluoroscopic Dysphagia Scale (VDS). The relationship between dysphagia scales and MPT was analyzed using Pearson correlation. The difference in VDS variables between subgroups (Parkinson disease or Parkinsonian syndrome, independent or dependent ambulation, and normal or abnormal MPT) and the difference in MPT between subgroups based on the VDS variables were analyzed using the independent t-test. RESULTS: Bolus formation and laryngeal elevation functions were significantly higher in the normal MPT group compared with the impaired group. In the VDS variables, patients with intact bolus formation, oral transit time, pharyngeal swallow triggering, and laryngeal elevation showed significantly longer MPTs compared with the impaired groups. In addition, MPT was significantly correlated with the VDS and modestly correlated with the NIH-SSS, but not the PAS, suggesting that phonatory function is related to the oropharyngeal swallowing function, but not directly to the aspiration itself. CONCLUSION: The correlation between MPT and several swallowing-related elements was identified, indicating an interactive correlation between swallowing and phonation. This result justifies voice therapy as a treatment for dysphagia in patients with Parkinsonism.

18.
Medicine (Baltimore) ; 96(34): e7472, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28834868

ABSTRACT

Intrathecal baclofen (ITB) has been known to reduce spasticity which did not respond to oral medications and botulinum toxin treatment. However, few results have been reported comparing the effects of ITB therapy in patients with cerebral palsy (CP) and acquired brain injury. This study aimed to investigate beneficial and adverse effects of ITB bolus injection and pump therapy in patients with CP and to compare outcomes to patients with acquired brain injury such as traumatic brain injury and hypoxic brain injury. ITB test trials were performed in 37 patients (19 CP and 18 acquired brain injury). Based on ambulatory function, CP patients were divided into 2 groups: 11 patients with nonambulatory CP and 8 patients with ambulatory CP. Change of spasticity was evaluated using the Modified Ashworth Scale. Additional positive or negative effects were also evaluated after ITB bolus injection. In patients who received ITB pump implantation, outcomes of spasticity, subjective satisfaction and adverse events were evaluated until 12 months post-treatment. After ITB bolus injection, 32 patients (86.5%) (CP 84.2% versus acquired brain injury 88.9%) showed a positive response of reducing spasticity. However, 8 patients with CP had negative adverse effects. Particularly, 3 ambulatory CP patients showed standing impairment and 1 ambulatory CP patient showed impaired gait pattern such as foot drop because of excessive reduction of lower extremity muscle tone. Ambulatory CP patients received ITB pump implantation less than patients with acquired brain injury after ITB test trials (P = .003 by a chi-squared test). After the pump implantation, spasticity was significantly reduced within 1 month and the effect maintained for 12 months. Seventeen patients or their caregivers (73.9%) were very satisfied, whereas 5 patients (21.7%) suffered from adverse events showed no subjective satisfaction. In conclusion, ITB therapy was effective in reducing spasticity in patients with CP and acquired brain injury. Before ITB pump implantation, it seems necessary to perform the ITB bolus injection to verify beneficial effects and adverse effects especially in ambulatory CP.


Subject(s)
Baclofen/therapeutic use , Brain Injuries/drug therapy , Cerebral Palsy/drug therapy , Muscle Relaxants, Central/therapeutic use , Muscle Spasticity/drug therapy , Adult , Baclofen/administration & dosage , Baclofen/adverse effects , Female , Humans , Infusion Pumps, Implantable , Injections, Spinal , Male , Mobility Limitation , Muscle Relaxants, Central/administration & dosage , Muscle Relaxants, Central/adverse effects , Patient Satisfaction
19.
ISA Trans ; 70: 209-218, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28716400

ABSTRACT

In this study, we present an identification-based direct construction of the inverse generalized Prandtl-Ishlinskii (P-I) model to facilitate inverse model-based feedforward compensation of asymmetric hysteresis nonlinearities. Compared with the derivation of the inverse model analytically from a generalized P-I model, this direct modeling approach has the following advantages. First, direct inverse model identification is formulated as a nonlinear optimization problem, which is not subject to the constraint condition on the generalized P-I model's threshold and density functions, where this is indispensable for the analytical model inversion procedure. Second, this approach may be a simple and attractive alternative when the identification precision of a generalized P-I model is limited by the constraint condition, which necessarily results in insufficient hysteresis compensation functionality for the analytically derived inverse model. Finally, direct inverse model identification can overcome the drawbacks of the analytical inversion method, including the accumulation of parameter estimation errors in an analytical inverse model because these parameters are computed from the generalized P-I model's parameters in a recursive manner. Our experimental results demonstrated that the implementation of open-loop control with the directly identified inverse generalized P-I model as a feedforward compensator achieved precise compensation for the asymmetric hysteresis nonlinearities of a piezoelectric stack actuator.

20.
Eur J Immunol ; 44(6): 1672-84, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24659444

ABSTRACT

Myeloid-derived suppressor cells (MDSCs), which suppress diverse innate and adaptive immune responses and thereby provide an evasion mechanism for tumors, are emerging as a key population linking inflammation to cancer. Although many inflammatory factors that induce MDSCs in the tumor microenvironment are known, the crucial components and the underlying mechanisms remain elusive. In this study, we proposed a novel mechanism by which serum amyloid A3 (SAA3), a well-known inflammatory factor, connects MDSCs with cancer progression. We found that SAA3 expression in BALB/c mice increased in monocytic MDSCs (Mo MDSCs) with tumor growth. The induction of SAA3 by apo-SAA treatment in Mo MDSCs enhanced their survival and suppressive activity, while it inhibited GM-CSF-induced differentiation. Endogenous SAA3 itself contributed to the increase in the survival and suppressive activity of Mo MDSCs. We demonstrated that SAA3 induced TLR2 signaling, in turn increasing the autocrine secretion of TNF-α, that led to STAT3 activation. In addition, activated STAT3 enhanced the suppressive activity of Mo MDSCs. Furthermore, SAA3 induction in Mo MDSCs contributed to accelerating tumor progression in vivo. Collectively, these data suggest a novel mechanism by which Mo MDSCs mediate inflammation through SAA3-TLR2 signaling and thus exacerbate cancer progression by a STAT3-dependent mechanism.


Subject(s)
Myeloid Cells/immunology , Neoplasms, Experimental/immunology , STAT3 Transcription Factor/immunology , Serum Amyloid A Protein/immunology , Toll-Like Receptor 2/immunology , Tumor Microenvironment/immunology , Animals , Cell Line, Tumor , Inflammation/immunology , Inflammation/pathology , Mice , Mice, Inbred BALB C , Myeloid Cells/pathology , Neoplasms, Experimental/pathology , Signal Transduction/immunology
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