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1.
Neuromodulation ; 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37552152

RESUMO

OBJECTIVES: There has been recent interest in the administration of transcranial electrical stimulation (tES) by a caregiver, family member, or patient themselves while in their own homes (HB-tES). The need to properly train individuals in the administration of HB-tES is essential, and the lack of a uniform training approach across studies has come to light. The primary aim of this paper is to present the HB-tES training and supervision program, a tele-supervised, instructional, and evaluation program to teach laypersons how to administer HB-tES to a participant and to provide a standardized framework for remote monitoring of participants by teaching staff. The secondary aim is to present early pilot data on the feasibility and effectiveness of the training portion of the program based on its implementation in 379 sessions between two pilot clinical trials. MATERIALS AND METHODS: The program includes instructional materials, standardized tele-supervised hands-on practice sessions, and a system for remote supervision of participants by teaching staff. Nine laypersons completed the training program. Data on the feasibility and effectiveness of the program were collected. RESULTS: No adverse events were reported during the training or any of the HB-tES sessions after the training. All laypersons successfully completed the training. The nine laypersons reported being satisfied with the training program and confident in their tES administration capabilities. This was consistent with laypersons requiring technical assistance from teaching staff very infrequently during the 379 completed sessions. The average adherence rate between all administrators was >98%, with seven of nine administrators having 100% adherence to the scheduled sessions. CONCLUSIONS: These findings indicate that the HB-tES program is effective and is associated with participant satisfaction. SIGNIFICANCE: We hope that the remote nature of this training program will facilitate increased accessibility to HB-tES research for participants of different demographics and locations. This program, designed for easy adaptation to different HB-tES research applications and devices, also is accessible online. The adoption of this program is expected to facilitate uniformity of study methods among future HB-tES studies and thereby accelerate the pace of tES intervention discovery.

2.
Ann Neurol ; 90(3): 428-439, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34216034

RESUMO

OBJECTIVE: Among older adults, the ability to stand or walk while performing cognitive tasks (ie, dual-tasking) requires coordinated activation of several brain networks. In this multicenter, double-blinded, randomized, and sham-controlled study, we examined the effects of modulating the excitability of the left dorsolateral prefrontal cortex (L-DLPFC) and the primary sensorimotor cortex (SM1) on dual-task performance "costs" to standing and walking. METHODS: Fifty-seven older adults without overt illness or disease completed 4 separate study visits during which they received 20 minutes of transcranial direct current stimulation (tDCS) optimized to facilitate the excitability of the L-DLPFC and SM1 simultaneously, or each region separately, or neither region (sham). Before and immediately after stimulation, participants completed a dual-task paradigm in which they were asked to stand and walk with and without concurrent performance of a serial-subtraction task. RESULTS: tDCS simultaneously targeting the L-DLPFC and SM1, as well as tDCS targeting the L-DLPFC alone, mitigated dual-task costs to standing and walking to a greater extent than tDCS targeting SM1 alone or sham (p < 0.02). Blinding efficacy was excellent and participant subjective belief in the type of stimulation received (real or sham) did not contribute to the observed functional benefits of tDCS. INTERPRETATION: These results demonstrate that in older adults, dual-task decrements may be amenable to change and implicate L-DPFC excitability as a modifiable component of the control system that enables dual-task standing and walking. tDCS may be used to improve resilience and the ability of older results to walk and stand under challenging conditions, potentially enhancing everyday functioning and reducing fall risks. ANN NEUROL 2021;90:428-439.


Assuntos
Envelhecimento/fisiologia , Marcha/fisiologia , Equilíbrio Postural/fisiologia , Córtex Pré-Frontal/fisiologia , Desempenho Psicomotor/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Humanos , Masculino , Projetos Piloto
3.
Chemistry ; 28(55): e202201664, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-35796204

RESUMO

Mesoscopic aggregate is important to transfer or even amplify the molecular information in macroscopic materials. As an important branch of aggregate science, aggregation-induced emissive luminogens (AIEgens) often show slight or even no emission in solutions but exhibit bright emission when they aggregate, which open a new avenue for the practical applications. Due to the flexible and rotor structure of AIEgens, the aggregate structure of AIEgens is highly sensitive to the surrounding microenvironment, resulting in adjustable optical properties. Fibers integrated of a multiplicity of functional components are ideal carriers to control the aggregation processes, further assembly of fibers produces large-scale fabrics with amplified functions and practical values. In this Concept article, we focus on the latest advances on the synergy between "AIE+Fiber" for the boosted performance that beyond AIE, and their applications are presented and abstracted out to stimulate new ideas for developing "AIE+Fiber" systems.

4.
J Virol ; 94(9)2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32075927

RESUMO

The capsid protein (Cap) is the sole structural protein and the main antigen of porcine circovirus type 2 (PCV2). Structural loops of the Cap play crucial roles in viral genome packaging, capsid assembly, and virus-host interactions. Although the molecular mechanisms are yet unknown, the carboxyl terminus (CT) of the PCV2 Cap is known to play critical roles in the evolution, pathogenesis, and proliferation of this virus. In this study, we investigated functions of CT. Removal of this loop leads to abrogation of the in vitro Cap self-assembly into virus-like particles (VLPs). Likewise, the mutated virus resists rescue from PK15 cell culture. A conserved PXXP motif in the CT is dispensable for VLP assembly and subsequent cell entry. However, its removal leads to the subsequent failure of virus rescued from PK15 cells. Furthermore, substituting either the PCV1 counterpart or an AXXA for the PXXP motif still supports virus rescue from cell culture but results in a dramatic decrease in viral titers compared with wild type. In particular, a strictly conserved residue (227K) in the CT is essential for VLP entry into PK15 cells, and its mutation to alanine greatly attenuates cell entry of the VLPs, supporting a mechanism for the failure to rescue a mutated PCV2 infectious DNA clone (K227A) from PK15 cell culture. These results suggest the CT of the PCV2 Cap plays critical roles in virus assembly, viral-host cell interaction(s), and virus propagation in vitroIMPORTANCE The carboxyl terminus (CT) of porcine circovirus type 2 (PCV2) capsid protein (Cap) was previously reported to be associated with immunorecognition, alterations of viral titer in swine sera, and pathogenicity. However, the molecular mechanisms underlying these effects remain unknown. In this study, roles of the critical residues and motifs of the CT are investigated with respect to virus-like particle (VLP) assembly, cell entry, and viral proliferation. The results revealed that the positively charged 227K of the CT is essential for both cell entry of PCV2 VLPs and virus proliferation. Our findings, therefore, suggest that the CT should be considered one of the key epitopes, recognized by neutralizing antibodies, for vaccine design and a target for drug development to prevent PCV2-associated diseases (PCVADs). Furthermore, it is important to respect the function of 227K for its role in cell entry if using either PCV2 VLPs for nanoscale DNA/drug cell delivery or using PCV2 VLPs to display a variety of foreign epitopes for immunization.


Assuntos
Proteínas do Capsídeo/metabolismo , Circovirus/metabolismo , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/imunologia , Capsídeo/metabolismo , Proteínas do Capsídeo/genética , Circoviridae/genética , Circoviridae/metabolismo , Infecções por Circoviridae/genética , Infecções por Circoviridae/metabolismo , Circovirus/genética , Epitopos/imunologia , Suínos , Doenças dos Suínos/virologia , Vacinas de Partículas Semelhantes a Vírus/imunologia , Montagem de Vírus/genética , Internalização do Vírus
5.
Ann Neurol ; 87(1): 75-83, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31693765

RESUMO

OBJECTIVE: Symptomatic head trauma associated with American-style football (ASF) has been linked to brain pathology, along with physical and mental distress in later life. However, the longer-term effects of such trauma on objective metrics of cognitive-motor function remain poorly understood. We hypothesized that ASF-related symptomatic head trauma would predict worse gait performance, particularly during dual task conditions (ie, walking while performing an additional cognitive task), in later life. METHODS: Sixty-six retired professional ASF players aged 29 to 75 years completed a health and wellness questionnaire. They also completed a validated smartphone-based assessment in their own homes, during which gait was monitored while they walked normally and while they performed a verbalized serial-subtraction cognitive task. RESULTS: Participants who reported more symptomatic head trauma, defined as the total number of impacts to the head or neck followed by concussion-related symptoms, exhibited greater dual task cost (ie, percentage increase) to stride time variability (ie, the coefficient of variation of mean stride time). Those who reported ≥1 hit followed by loss of consciousness, compared to those who did not, also exhibited greater dual task costs to this metric. Relationships between reported trauma and dual task costs were independent of age, body mass index, National Football League career duration, and history of musculoskeletal surgery. Symptomatic head trauma was not correlated with average stride times in either walking condition. INTERPRETATION: Remote, smartphone-based assessments of dual task walking may be utilized to capture meaningful data sensitive to the long-term impact of symptomatic head trauma in former professional ASF players and other contact sport athletes. ANN NEUROL 2020;87:75-83.


Assuntos
Cognição/fisiologia , Traumatismos Craniocerebrais/fisiopatologia , Futebol Americano/lesões , Marcha/fisiologia , Adulto , Idoso , Concussão Encefálica/complicações , Concussão Encefálica/fisiopatologia , Traumatismos Craniocerebrais/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Tecnologia de Sensoriamento Remoto/métodos , Aposentadoria , Autorrelato , Smartphone/estatística & dados numéricos , Inquéritos e Questionários
6.
J Biol Chem ; 293(39): 15221-15232, 2018 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-30108178

RESUMO

Porcine circovirus type 2 (PCV2) is one of the smallest, nonenveloped, single-stranded DNA viruses. The PCV2 capsid protein (Cap) is the sole viral structural protein and main antigenic determinant. Previous sequence analysis has revealed that the N terminus of the PCV2 Cap contains a nuclear localization signal (NLS) enriched in positively charged residues. Here, we report that PCV2's NLS can function as a cell-penetrating peptide (CPP). We observed that this NLS can carry macromolecules, e.g. enhanced GFP (EGFP), into cells when they are fused to the NLS, indicating that it can function as a CPP, similar to the classical CPP derived from HIV type 1 transactivator of transcription protein (HIV TAT). We also found that the first 17 residues of the NLS (NLS-A) have a key role in cellular uptake. In addition to entering cells via multiple endocytic processes, NLS-A was also rapidly internalized via direct translocation enabled by increased membrane permeability and was evenly distributed throughout cells when its concentration in cell cultures was ≥10 µm Of note, cellular NLS-A uptake was ∼10 times more efficient than that of HIV TAT. We inferred that the externalized NLS of the PCV2 Cap may accumulate to a high concentration (≥10 µm) at a local membrane area, increasing membrane permeability to facilitate viral entry into the cell to release its genome into a viral DNA reproduction center. We conclude that NLS-A has potential as a versatile vehicle for shuttling foreign molecules into cells, including pharmaceuticals for therapeutic interventions.


Assuntos
Proteínas do Capsídeo/genética , Peptídeos Penetradores de Células/genética , Sinais de Localização Nuclear/genética , Produtos do Gene rev do Vírus da Imunodeficiência Humana/genética , Animais , Anticorpos Antivirais/química , Anticorpos Antivirais/imunologia , Proteínas do Capsídeo/química , Proteínas do Capsídeo/farmacologia , Peptídeos Penetradores de Células/química , Peptídeos Penetradores de Células/farmacologia , Circovirus/química , Circovirus/genética , DNA de Cadeia Simples/química , DNA de Cadeia Simples/genética , DNA Viral/química , DNA Viral/genética , DNA Viral/farmacologia , Epitopos/química , Epitopos/genética , Epitopos/imunologia , Humanos , Sinais de Localização Nuclear/química , Suínos , Produtos do Gene rev do Vírus da Imunodeficiência Humana/química
7.
Biomed Chromatogr ; 33(3): e4424, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30403410

RESUMO

As chlorpyrifos is used globally to control pests in sugarcane fields, analysis of its residues on food crops is essential to assess product safety for humans. In this study, chlorpyrifos content in sugarcane plants, soil and juice was determined using a gas chromatography with an electron capture detector. The limit of quantification was 0.01 mg/kg for plant and soil, and 0.01 mg/L for juice. The degradation and residual risk in sugarcane fields after applying chlorpyrifos to two sample sites (Changsha and Danzhou, China) were assessed. Chlorpyrifos concentrations in plants and soil decreased rapidly over time, reaching a degradation rate ranging from 98.82 to 99.25% on day 35. The half-life of chlorpyrifos in both plants and soil was only 5.97-6.12 days. Regardless of application dosage (standard or high) at a pre-harvest interval of 60 days, chlorpyrifos was undetectable in the harvested sugarcane. Risk assessment indicated that chlorpyrifos residue in sugarcane did not pose a health risk to humans.


Assuntos
Clorpirifos/química , Monitoramento Ambiental/métodos , Resíduos de Praguicidas/química , Saccharum/química , Poluentes do Solo/química , Clorpirifos/análise , Cromatografia Gasosa , Limite de Detecção , Modelos Lineares , Resíduos de Praguicidas/análise , Reprodutibilidade dos Testes , Medição de Risco , Poluentes do Solo/análise
8.
J Med Ultrasound ; 27(3): 130-134, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31867175

RESUMO

BACKGROUND: Acoustic radiation force impulse (ARFI) imaging is a popular modality to measure liver fibrosis. ARFI selects optimal locations for measurement under imaging guiding. However, there are concerns on study locations and observers bias. To decrease the variations, ARFI at two locations was measured with standardized protocol. This study attempted to establish its cutoff values according to Metavir fibrosis score in different etiologies. METHODS: A consecutive series of patients who received liver histology study were prospectively enrolled. All cases had hemogram, liver biochemistry, viral markers, and ARFI two-location measurements within 4 weeks of histology study. A standardized protocol was performed by single technologist. We excluded patients with alanine aminotransferase >5x upper limit normal. RESULTS: Five hundred and ten patients that included 153 seronegative for both HBsAg and anti-HCV Non-B non-C (NBNC), 33 autoimmune liver diseases (AILD), 261 chronic hepatitis B (CHB), and 63 chronic hepatitis C (CHC) were enrolled. About 83% of NBNC patients had fat cell >5%. For diagnosis of liver cirrhosis, the area under receiver operating characteristic curve of NBNC, AILD, CHB, and CHC groups was 0.937, 0.929, 0.784, and 0.937; the cutoff values for mean ARFI were 1.788, 2.095, 1.455, and 1.710 m/s, respectively. The sensitivity and specificity are both over 0.818 for patients with nonalcoholic fatty liver diseases, CHC, and AILD, but the corresponding data are only 0.727-0.756 in CHB. The Fibrosis-4 Score is as good as ARFI on fibrosis assessment in NBNC. CONCLUSION: The performance of ARFI two-location measurement is excellent in NBNC, AILD, and CHC, but is only satisfactory in CHB.

9.
Sensors (Basel) ; 18(3)2018 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-29562601

RESUMO

A novel geolocation architecture, termed "Multiple Transponders and Multiple Receivers for Multiple Emitters Positioning System (MTRE)" is proposed in this paper. Existing Direct Position Determination (DPD) methods take advantage of a rather simple channel assumption (line of sight channels with complex path attenuations) and a simplified MUltiple SIgnal Classification (MUSIC) algorithm cost function to avoid the high dimension searching. We point out that the simplified assumption and cost function reduce the positioning accuracy because of the singularity of the array manifold in a multi-path environment. We present a DPD model for unknown signals in the presence of Multi-path Propagation (MP-DPD) in this paper. MP-DPD adds non-negative real path attenuation constraints to avoid the mistake caused by the singularity of the array manifold. The Multi-path Propagation MUSIC (MP-MUSIC) method and the Active Set Algorithm (ASA) are designed to reduce the dimension of searching. A Multi-path Propagation Maximum Likelihood (MP-ML) method is proposed in addition to overcome the limitation of MP-MUSIC in the sense of a time-sensitive application. An iterative algorithm and an approach of initial value setting are given to make the MP-ML time consumption acceptable. Numerical results validate the performances improvement of MP-MUSIC and MP-ML. A closed form of the Cramér-Rao Lower Bound (CRLB) is derived as a benchmark to evaluate the performances of MP-MUSIC and MP-ML.

11.
Acta Vet Hung ; 65(2): 278-290, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28605956

RESUMO

Porcine circovirus associated diseases (PCVAD) caused by PCV2 are responsible for severe economic losses in the swine industry. The mechanism of PCV2 replication has not been fully elucidated yet. PCV2 may be successfully rescued by means of either an infectious DNA clone containing the full length of the viral genomic DNA, or from PCV2-infected clinical tissues in PK15 cell culture. However, viruses harvested by both methods have low titres. In this study, PCV2 was prepared with a higher titre from PK15 cells infected by recombinant baculoviruses containing 1PCV2 (one stem-loop structure) or 1.1PCV2 (two stem-loop structure) genomic DNA copy. In addition, infectious DNA clones containing two stem-loop structures in either plasmid or baculovirus backbones are capable of generating a higher virus titre than the DNA clones with only one copy of stem-loop structure.


Assuntos
Circovirus/fisiologia , Genoma Viral/fisiologia , Animais , Baculoviridae/genética , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Linhagem Celular , Engenharia Genética/métodos , Recombinação Genética , Suínos
12.
Arch Virol ; 161(6): 1485-91, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26973229

RESUMO

Porcine circovirus type 2 (PCV2) causes increased mortality and poor growth or weight loss in apparently healthy swine. Therefore, methods to detect PCV2-specific antibodies in swine serum are important for prevention, diagnosis, and control of PCV2-associated diseases (PCVAD). In this study, PCV2 virus-like particles (VLPs) were used to develop a rapid, simple and economical indirect enzyme-linked immunosorbent assay to detect (with high sensitivity) PCV2-specific antibodies in swine serum. The PCV2 capsid protein (Cap) was overexpressed in E. coli after optimizing the cap gene. Subsequently, the soluble Cap was rapidly purified in one step by automated fast protein liquid chromatography (FPLC). The purified PCV2 Cap was shown by transmission electron microscopy and gel filtration chromatography to be capable of self-assembling into VLPs in vitro. Using the purified VLPs as antigens, optimal operating conditions for the VLP ELISA were determined. The concentration of PCV2 VLPs was 1 µg/ml per well, and the dilution factors for swine serum and horseradish peroxidase (HRP)-labeled goat anti-pig antibody were 1:150 and 1:4000, respectively. Out of 241 serum samples tested with this assay, 83.4 % were found to be positive. Importantly, the VLP ELISA had a total coincidence rate of 97.4 % (74/76) compared to an Ingezim PCV2 ELISA IgG assay. In summary, this rapid, inexpensive VLP ELISA has the potential to greatly facilitate large-scale investigations of PCV2-associated serotypes.


Assuntos
Circovirus/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Animais , Anticorpos Antivirais/sangue , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/veterinária , Circovirus/classificação , Circovirus/genética , Ensaio de Imunoadsorção Enzimática/métodos , Escherichia coli/genética , Escherichia coli/imunologia , Imunoglobulina G/sangue , Sorogrupo , Sus scrofa , Suínos/imunologia , Doenças dos Suínos/imunologia , Doenças dos Suínos/virologia , Vacinas de Partículas Semelhantes a Vírus/genética , Vacinas de Partículas Semelhantes a Vírus/imunologia
14.
Anal Chem ; 87(8): 4231-6, 2015 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-25811916

RESUMO

Enzyme-catalyzed signal amplification with an antibody-enzyme conjugate is commonly employed in many bioanalytical methods to increase assay sensitivity. However, covalent labeling of the enzyme to the antibody, laborious operating procedures, and extensive washing steps are necessary for protein recognition and signal amplification. Herein, we describe a novel label-free and washing-free enzyme-amplified protein detection method by using dual-functional synthetic molecules to impose steric effects upon protein binding. In our approach, protein recognition and signal amplification are modulated by a simple dual-functional synthetic probe which consists of a protein ligand and an inhibitor. In the absence of the target protein, the inhibitor from the dual-functional probe would inhibit the enzyme activity. In contrast, binding of the target protein to the ligand perturbs this enzyme-inhibitor affinity due to the generation of steric effects caused by the close proximity between the target protein and the enzyme, thereby activating the enzyme to initiate signal amplification. With this strategy, the fluorescence signal can be amplified to as high as 70-fold. The generality and versatility of this strategy are demonstrated by the rapid, selective, and sensitive detection of four different proteins, avidin, O6-methylguanine DNA methyltransferase (MGMT), SNAP-tag, and lactoferrin, with four different probes.


Assuntos
Avidina/análise , Anidrase Carbônica II/metabolismo , Corantes Fluorescentes/química , Lactoferrina/análise , O(6)-Metilguanina-DNA Metiltransferase/análise , Corantes Fluorescentes/síntese química , Humanos , Ligantes , Estrutura Molecular , O(6)-Metilguanina-DNA Metiltransferase/metabolismo
15.
Pestic Biochem Physiol ; 121: 129-35, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26047121

RESUMO

Metabolic resistance to synthetic pyrethroids in Helicoverpa armigera has recently been associated with the chimeric cytochrome P450 enyzme CYP337B3. One variant of the latter, CYP337B3v1, accounts for 40-50 fold resistance to fenvalerate in an Australian population while a second variant, CYP337B3v2, has been associated with ~7 fold resistance to cypermethrin in a Pakistani population. Here we show that ~250-1200 fold resistance to fenvalerate in populations of the species from northern and northwestern China is largely due to P450-based metabolism, and that CYP337B3v2 is also at high frequency in these populations but absent in a susceptible control strain. However we find little correlation between the level of resistance and CYP337B3v2 frequency, either across the resistant populations studied, or over time within them. While there is variation between populations in the levels of CYP337B3v2 expression, this is not correlated with the level of resistance either. These data suggest that much of the variation in the level of fenvalerate resistance in China is explained by P450s other than CYP337B3. We also find that both the level of resistance and CYP337B3v2 frequency decline in field populations transferred to the laboratory and remained there without fenvalerate exposure, suggesting a fitness cost to both characters in the absence of the pesticide pressure. However the declines in the two characters are not well correlated across populations, again consistent with a large contribution to the variation in resistance levels from factors other than CYP337B3.


Assuntos
Proteínas de Insetos/genética , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Mariposas/genética , Nitrilas/farmacologia , Piretrinas/farmacologia , Animais , China , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Esterases/metabolismo , Genótipo , Glutationa Transferase/metabolismo , Proteínas de Insetos/metabolismo , Larva/efeitos dos fármacos , Larva/enzimologia , Larva/genética , Oxigenases de Função Mista/metabolismo , Mariposas/efeitos dos fármacos , Mariposas/enzimologia
16.
J Aging Environ ; 38(1): 18-36, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38465201

RESUMO

Technology provides new opportunities to understand and optimize the relationship between the home indoor environmental quality and health outcomes in older adults. We aimed to establish proof-of-concept and feasibility of remote, real-time, high-frequency, and simultaneous monitoring of select environmental variables and outcomes related to health and wellbeing in older adults. Thirty-four participants (27 were female) with an average age (SD) of 81 years (±7.1) were recruited from community and supportive housing environments. Environmental sensors were installed in each home and participants were asked to use a wearable device on their finger and answer smartphone-based questionnaires on a daily basis. Further, a subgroup of participants were asked to complete tablet-based cognitive tests on a daily basis. Average compliance with the wearable (time worn properly / total time with device) was 81%. Participants responded to 69% of daily smartphone surveys and completed 80% of the prescribed cognitive tests. These results suggest that it is feasible to study the impact of the home thermal environment and air quality on biological rhythms, cognition, and other outcomes in older adults. However, the success of non-passive data collection elements may be contingent upon baseline cognition.

17.
J Vet Res ; 68(2): 295-302, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38947147

RESUMO

Introduction: When piglets are exposed to pathogens for a long period, the immune system organs, among them the spleen, play a major role in combating the stress caused by those pathogens. In the present study, the effect on splenocyte function was investigated in a model of weaned piglets in which stress was induced by multiple low doses of lipopolysaccharide (LPS). Material and Methods: Forty-eight 28-day-old piglets were divided into two groups: the LPS group and the control group. During the experimental period of thirteen days, the LPS group was intraperitoneally injected with LPS (100 µg/kg) once per day, and the control group was injected with the same volume of 0.9% sterile saline. On the 1st, 5th, 9th and 13th days, the piglets' spleens were collected for isolating splenocytes. The proliferation ability of splenocytes was evaluated by the cell-counting-kit 8 method. Flow cytometry was used to detect cell cycle stage and apoptosis, and the nitric oxide level of cell supernatant was also tested. Results: In the experimental group, the proliferation ability of splenocytes was enhanced, the proportion of cells in the G0/G1 phase was smaller, and cells were promoted to the S and G2/M phases. Meanwhile, apoptosis was suppressed and nitric oxide release upregulated. The results were significantly different between the LPS group and the control group on the 5th and 9th days. Conclusion: The difference between the results of one group and those of the other suggest that after the 5th LPS injection, multiple low doses of LPS activated splenocytes and restored the number of splenocytes, which maintained and possibly enhanced the regulation of the immune function of the spleen.

18.
Artigo em Inglês | MEDLINE | ID: mdl-38853485

RESUMO

BACKGROUND: The hemodynamics of prefrontal cortex (PFC) oxygenation are regulated by numerous processes operating over multiple temporal scales, producing complex patterns in its output fluctuations. Age may alter this multiscale regulation of PFC oxygenation, leading to diminished physiologic complexity of this important regulatory process. We aimed to characterize the effects of age on such complexity and its relationship to performance of an executive n-back task. METHODS: Twenty-four younger (aged 28±3 years) and 27 older (aged 78±6 years) adults completed this study. Continuous oxygenation (HbO2) and deoxygenation (HHb) signals of PFC were recorded using functional near-infrared-spectroscopy (fNIRS) while participants stood and watched a blank screen (blank), clicked a mouse when an X appeared (IdX) or when a letter was repeated from "2-back" in a sequence shown on a screen (2-back). We used multiscale entropy to quantify the HbO2 and HHb complexity of fNIRS signals. RESULTS: Older adults exhibited lower HbO2 and HHb complexity compared to younger adults, regardless of task (p=0.0005~0.002). Both groups exhibited greater complexity during the IdX and 2-back than blank task (p=0.02~0.04). Across all participants, those with greater HbO2 and/or HHb complexity during the blank task exhibited faster IdX and 2-back reaction time (ß=-0.56~-0.6, p=0.009~0.02). Those demonstrating greater increase of HbO2 and/or HHb complexity from IdX to 2-back task had lower percent increase in reaction time from IdX to 2-back task (ß=-0.41~-0.37, p=0.005~0.01). CONCLUSION: The complexity of fNIRS-measured PFC oxygenation fluctuations may capture the influence of aging on the regulation of prefrontal hemodynamics involved in executive-function-based task performance.

19.
Bioengineering (Basel) ; 11(3)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38534531

RESUMO

The four-meter gait speed (4MGS) is a recommended physical performance test in older adults but is challenging to implement clinically. We developed a smartphone application (App) with a four-meter ribbon for remote 4MGS testing at home. This study aimed to assess the validity and reliability of this smartphone App-based assessment of the home 4MGS. We assessed the validity of the smartphone App by comparing it against a gold standard video assessment of the 4MGS conducted by study staff visiting community-dwelling older adults and against the stopwatch-based measurement. Moreover, we assessed the test-retest reliability in two supervised sessions and three additional sessions performed by the participants independently, without staff supervision. The 4MGS measured by the smartphone App was highly correlated with video-based 4MGS (r = 0.94), with minimal differences (mean = 0.07 m/s, ± 1.96 SD = 0.12) across a range of gait speeds. The test-retest reliability for the smartphone App 4MGS was high (ICC values: 0.75 to 0.93). The home 4MGS in older adults can be measured accurately and reliably using a smartphone in the pants pocket and a four-meter strip of ribbon. Leveraging existing technology carried by a significant portion of the older adult population could overcome barriers in busy clinical settings for this well-established objective mobility test.

20.
J Comput Biol ; 30(10): 1131-1143, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37729064

RESUMO

Phage virion proteins (PVPs) play an important role in the host cell. Fast and accurate identification of PVPs is beneficial for the discovery and development of related drugs. Although wet experimental approaches are the first choice to identify PVPs, they are costly and time-consuming. Thus, researchers have turned their attention to computational models, which can speed up related studies. Therefore, we proposed a novel machine-learning model to identify PVPs in the current study. First, 50 different types of physicochemical properties were used to denote protein sequences. Next, two different approaches, including Pearson's correlation coefficient (PCC) and maximal information coefficient (MIC), were employed to extract discriminative information. Further, to capture the high-order correlation information, we used PCC and MIC once again. After that, we adopted the least absolute shrinkage and selection operator algorithm to select the optimal feature subset. Finally, these chosen features were fed into a support vector machine to discriminate PVPs from phage non-virion proteins. We performed experiments on two different datasets to validate the effectiveness of our proposed method. Experimental results showed a significant improvement in performance compared with state-of-the-art approaches. It indicates that the proposed computational model may become a powerful predictor in identifying PVPs.

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