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1.
J Biomed Sci ; 29(1): 37, 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35681239

RESUMO

BACKGROUND: Calls for the coronavirus to be treated as an endemic illness, such as the flu, are increasing. After achieving high coverage of COVID-19 vaccination, therapeutic drugs have become important for future SARS-CoV-2 variant outbreaks. Although many monoclonal antibodies have been approved for emergency use as treatments for SARS-CoV-2 infection, some monoclonal antibodies are not authorized for variant treatment. Broad-spectrum monoclonal antibodies are unmet medical needs. METHODS: We used a DNA prime-protein boost approach to generate high-quality monoclonal antibodies. A standard ELISA was employed for the primary screen, and spike protein-human angiotensin-converting enzyme 2 blocking assays were used for the secondary screen. The top 5 blocking clones were selected for further characterization, including binding ability, neutralization potency, and epitope mapping. The therapeutic effects of the best monoclonal antibody against SARS-CoV-2 infection were evaluated in a hamster infection model. RESULTS: Several monoclonal antibodies were selected that neutralize different SARS-CoV-2 variants of concern (VOCs). These VOCs include Alpha, Beta, Gamma, Delta, Kappa and Lambda variants. The high neutralizing antibody titers against the Beta variant would be important to treat Beta-like variants. Among these monoclonal antibodies, mAb-S5 displays the best potency in terms of binding affinity and neutralizing capacity. Importantly, mAb-S5 protects animals from SARS-CoV-2 challenge, including the Wuhan strain, D614G, Alpha and Delta variants, although mAb-S5 exhibits decreased neutralization potency against the Delta variant. Furthermore, the identified neutralizing epitopes of monoclonal antibodies are all located in the receptor-binding domain (RBD) of the spike protein but in different regions. CONCLUSIONS: Our approach generates high-potency monoclonal antibodies against a broad spectrum of VOCs. Multiple monoclonal antibody combinations may be the best strategy to treat future SARS-CoV-2 variant outbreaks.


Assuntos
Anticorpos Monoclonais , Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Animais , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/uso terapêutico , Vacinas contra COVID-19 , Cricetinae , Humanos , Glicoproteína da Espícula de Coronavírus/genética
2.
Int J Mol Sci ; 22(16)2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34445789

RESUMO

The SARS-CoV-2 pseudovirus is a commonly used strategy that mimics certain biological functions of the authentic virus by relying on biological legitimacy at the molecular level. Despite the fact that spike (S), envelope (E), and membrane (M) proteins together wrap up the SARS-CoV-2 virion, most of the reported pseudotype viruses consist of only the S protein. Here, we report that the presence of E and M increased the virion infectivity by promoting the S protein priming. The S, E, and M (SEM)-coated pseudovirion is spherical, containing crown-like spikes on the surface. Both S and SEM pseudoviruses packaged the same amounts of viral RNA, but the SEM virus bound more efficiently to cells stably expressing the viral receptor human angiotensin-converting enzyme II (hACE2) and became more infectious. Using this SEM pseudovirus, we examined the infectivity and antigenic properties of the natural SARS-CoV-2 variants. We showed that some variants have higher infectivity than the original virus and that some render the neutralizing plasma with lower potency. These studies thus revealed possible mechanisms of the dissemination advantage of these variants. Hence, the SEM pseudovirion provides a useful tool to evaluate the viral infectivity and capability of convalescent sera in neutralizing specific SARS-CoV-2 S dominant variants.


Assuntos
Anticorpos Antivirais/metabolismo , COVID-19/imunologia , Proteínas do Envelope de Coronavírus/metabolismo , SARS-CoV-2/patogenicidade , Proteínas da Matriz Viral/metabolismo , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Anticorpos Antivirais/imunologia , COVID-19/sangue , COVID-19/virologia , Linhagem Celular , Proteínas do Envelope de Coronavírus/genética , Proteínas do Envelope de Coronavírus/imunologia , Proteínas do Envelope de Coronavírus/ultraestrutura , Cricetinae , Humanos , Microscopia Eletrônica de Transmissão , Mutação , Testes de Neutralização , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Proteínas da Matriz Viral/genética , Proteínas da Matriz Viral/imunologia , Proteínas da Matriz Viral/ultraestrutura , Vírion/genética , Vírion/imunologia , Vírion/metabolismo , Vírion/ultraestrutura
3.
Appl Opt ; 59(1): 201-209, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32225289

RESUMO

While using digital halftoning to achieve multi-tones in a 1 bit electrophoretic display (EPD), e.g., a three-pigment chromatic EPD, the drive current is significantly increased because of frequently reversed pixel values. Aimed at this issue, this study first establishes a model that can accurately predict the drive current from image content. Next, based on the direct binary search method, a new halftoning method is proposed by constructing a combined merit function that incorporates both the perceptual image quality and the drive current. As a result, in experiments using a 13.5 in. three-pigment EPD and several test images, compared with the well-developed error-diffusion method, the proposed method produces little image quality degradation, whereas the drive current increase with respect to the minimum current of the EPD is reduced from 71.8 to 33.0 mA, for a significant reduction of 54.0%.

4.
Rheumatol Int ; 37(2): 273-279, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27844125

RESUMO

Previous cross-sectional studies have suggested an association between migraine and rheumatoid arthritis (RA), but no longitudinal study has been performed to evaluate the temporal relationship between the two conditions. The purpose of the present population-based, propensity score-matched cohort study was to investigate whether migraineurs are at a higher risk of developing RA. A total of 58,749 subjects aged between 20 and 90 years with at least two ambulatory visits with a diagnosis of migraine were recruited in the migraine group. We fit a logistic regression model that included age, sex, comorbid conditions, and socioeconomic status as covariates to compute the propensity score. The non-migraine group consisted of 58,749 propensity score-matched, randomly sampled subjects without migraine. The RA-free survival curves were generated using the Kaplan-Meier method. Stratified Cox proportional hazard regression was used to estimate the effect of migraine on the risk of RA. During follow-up, 461 subjects in the migraine group and 220 in the non-migraine group developed RA. The incidence rate of RA was 3.18 (95% confidence interval [CI] 2.90-3.49) per 1000 person-years in the migraine group and 1.54 (95% CI 1.34-1.76) per 1000 person-years in the non-migraine group. Compared to the non-migraine group, the crude hazard ratio of RA for the migraine group was 2.15 (95% CI 1.82-2.56, P < 0.0001), and the multivariable-adjusted hazard ratio was 1.91 (95% CI 1.58-2.31, P < 0.0001). This study showed that patients with migraine had an increased risk of developing RA.


Assuntos
Artrite Reumatoide/epidemiologia , Transtornos de Enxaqueca/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Artrite Reumatoide/etiologia , Feminino , Seguimentos , Humanos , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Risco , Adulto Jovem
5.
Cephalalgia ; 36(14): 1316-1323, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26853806

RESUMO

BACKGROUND: The association between migraine and Parkinson's disease (PD) remains controversial. The purpose of the present population-based, propensity score-matched follow-up study was to investigate whether migraineurs are at a higher risk of developing PD. METHODS: A total of 41,019 subjects aged between 40 and 90 years with at least two ambulatory visits with a diagnosis of migraine in 2001 were enrolled in the migraine group. A logistic regression model that included age, sex, pre-existing comorbidities and socioeconomic status as covariates was used to compute the propensity score. The non-migraine group consisted of 41,019 propensity score-matched, randomly sampled subjects without migraine. The PD-free survival rate were estimated using the Kaplan-Meier method. Stratified Cox proportional hazard regression was used to estimate the effect of migraine on the risk of developing PD. RESULTS: During follow-up, 148 subjects in the migraine group and 101 in the non-migraine group developed PD. Compared to the non-migraine group, the hazard ratio of PD for the migraine group was 1.64 (95% confidence interval: 1.25-2.14, p = 0.0004). The PD-free survival rate for the migraine group was significantly lower than that for the non-migraine group (p = 0.0041). CONCLUSIONS: This study showed an increased risk of developing PD in patients with migraine.


Assuntos
Transtornos de Enxaqueca/diagnóstico , Transtornos de Enxaqueca/epidemiologia , Doença de Parkinson/diagnóstico , Doença de Parkinson/epidemiologia , Vigilância da População , Pontuação de Propensão , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Vigilância da População/métodos , Fatores de Risco , Taiwan/epidemiologia
6.
Nat Commun ; 15(1): 6607, 2024 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-39098891

RESUMO

Delivering synthetic protein-coding RNA bypassing the DNA stage for ectopic protein functioning is a novel therapeutic strategy. Joining the linear RNA head-to-tail covalently could be a state-of-the-art strategy for functioning longer. Here we enroll a cis-acting ligase ribozyme (RzL) to generate circular RNA (circRNA) in vitro for ectopic protein expression. The RNA circularization is confirmed by masking the 5' phosphate group, resisting exonuclease RNase R digestion, failing for further tailing, and sequencing the RT-PCR products of the joined region. Interestingly, one internal ribosome entry site (IRES) renders circRNA translation competent, but two IRES in cis, not trans, hamper the translation. The circRNA with highly potent in translation is conferred for antiviral functioning. Accompanying specific guided RNA, a circRNA expressing ribonuclease Cas13 shows excellent potential against the corresponding RNA virus, further extending circRNA functioning in its growing list of applications.


Assuntos
RNA Catalítico , RNA Circular , RNA Circular/metabolismo , RNA Circular/genética , RNA Catalítico/metabolismo , RNA Catalítico/genética , Humanos , Sítios Internos de Entrada Ribossomal , Biossíntese de Proteínas , RNA/metabolismo , RNA/genética , Células HEK293 , Exorribonucleases
7.
Mol Ther Oncolytics ; 28: 104-117, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36699618

RESUMO

Glioblastoma (GBM) is the most common aggressive malignant brain cancer and is chemo- and radioresistant, with poor therapeutic outcomes. The "double-edged sword" of virus-induced cell death could be a potential solution if the oncolytic virus specifically kills cancer cells but spares normal ones. Zika virus (ZIKV) has been defined as a prospective oncolytic virus by selectively targeting GBM cells, but unclear understanding of how ZIKV kills GBM and the consequences hinders its application. Here, we found that the cellular gasdermin D (GSDMD) is required for the efficient death of a human GBM cell line caused by ZIKV infection. The ZIKV protease specifically cleaves human GSDMD to activate caspase-independent pyroptosis, harming both viral protease-harboring and naive neighboring cells. Analyzing human GSDMD variants showed that most people were susceptible to ZIKV-induced cytotoxicity, except for those with variants that resisted ZIKV cleavage or were defective in oligomerizing the N terminus GSDMD cleavage product. Consistently, ZIKV-induced secretion of the pro-inflammatory cytokine interleukin-1ß and cytolytic activity were both stopped by a small-molecule inhibitor targeting GSDMD oligomerization. Thus, potential ZIKV oncolytic therapy for GBM would depend on the patient's GSDMD genetic background and could be abolished by GSDMD inhibitors if required.

8.
J Cell Mol Med ; 16(3): 582-93, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21545685

RESUMO

Aging has less effect on adipose-derived mesenchymal stem cells (ADSCs) than on bone marrow-derived mesenchymal stem cells (BMSCs), but whether the fact holds true in stem cells from elderly patients with osteoporotic fractures is unknown. In this study, ADSCs and BMSCs of the same donor were harvested and divided into two age groups. Group A consisted of 14 young patients (36.4 ± 11.8 years old), and group B consisted of eight elderly patients (71.4 ± 3.6 years old) with osteoporotic fractures. We found that the doubling time of ADSCs from both age groups was maintained below 70 hrs, while that of BMSCs increased significantly with the number of passage. When ADSCs and BMSCs from the same patient were compared, there was a significant increase in the doubling time of BMSCs in each individual from passages 3 to 6. On osteogenic induction, the level of matrix mineralization of ADSCs from group B was comparable to that of ADSCs from group A, whereas BMSCs from group B produced least amount of mineral deposits and had a lower expression level of osteogenic genes. The p21 gene expression and senescence-associated ß-galactosidase activity were lower in ADSCs compared to BMSCs, which may be partly responsible for the greater proliferation and differentiation potential of ADSCs. It is concluded that the proliferation and osteogenic differentiation of ADSCs were less affected by age and multiple passage than BMSCs, suggesting that ADSCs may become a potentially effective therapeutic option for cell-based therapy, especially in elderly patients with osteoporosis.


Assuntos
Tecido Adiposo/patologia , Envelhecimento/patologia , Células-Tronco Mesenquimais/patologia , Osteoporose/patologia , Fraturas por Osteoporose/patologia , Tecido Adiposo/metabolismo , Adulto , Idoso , Envelhecimento/metabolismo , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Diferenciação Celular , Proliferação de Células , Transplante de Células , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Feminino , Expressão Gênica , Humanos , Masculino , Células-Tronco Mesenquimais/metabolismo , Osteogênese/fisiologia , Osteoporose/metabolismo , Osteoporose/terapia , Fraturas por Osteoporose/metabolismo , Fraturas por Osteoporose/terapia , Cultura Primária de Células , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
9.
J Biomed Biotechnol ; 2012: 498051, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22577293

RESUMO

Few rejuvenation and antiaging markers are used to evaluate food supplements. We measured three markers in peripheral blood to evaluate the antiaging effects of a food supplement containing placental extract. Samples were evaluated for CD34(+) cells, insulin-like growth factor 1 (IGF1), and telomerase activity, which are all markers related to aging. To control the quality of this food supplement, five active components were monitored. In total, we examined 44 individuals who took the food supplement from 1.2 months to 23 months; the average number of CD34(+) cells was almost 6-fold higher in the experimental group compared with the control group. Food supplement intake did not change serum IGF1 levels significantly. Finally, the average telomerase activity was 30% higher in the subjects taking this food supplement. In summary, our results suggest that the placental extract in the food supplement might contribute to rejuvenation and antiaging.


Assuntos
Antígenos CD34/metabolismo , Suplementos Nutricionais , Células-Tronco/efeitos dos fármacos , Telomerase/metabolismo , Adulto , Fatores Etários , Animais , Antígenos CD34/sangue , Método Duplo-Cego , Feminino , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Pessoa de Meia-Idade , Placebos , Placenta/efeitos dos fármacos , Placenta/metabolismo , Gravidez , Análise de Regressão , Células-Tronco/metabolismo , Suínos , Telomerase/sangue
10.
Nutrients ; 13(6)2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34071812

RESUMO

The tongue plays an important role in swallowing, and its dysfunction theoretically leads to inadequate oral intake and subsequent malnutrition. This study aimed to explore how different levels of tongue pressure are related to malnutrition among community-dwelling older individuals. The target population was community-dwelling adults aged ≥ 65 years. Tongue pressure was measured using the Iowa Oral Performance Instrument, whereas the mini nutrition assessment (MNA) test was administered to determine the nutritional status. A full MNA score of less than 24 points was defined as risk of malnutrition. Multivariate logistic regression analyses were conducted to calculate the odds ratio (OR) of risk of malnutrition among different quartiles of tongue pressure. Among the 362 participants, 26 (7.1%) were classified as having risk of malnutrition. Body weight, body mass index, handgrip strength, skeletal muscle mass index, sum MNA score, and serum levels of albumin were lower in the malnutrition risk groups than in the normal nutrition status group. A positive correlation was identified between tongue pressure and the MNA score (r = 0.143, p < 0.01). Treating the subgroup of the highest quartile of tongue pressure as the reference, the crude odds ratio (OR) of having risk of malnutrition was 5.37 (95% CI, 1.14-25.28) in the subgroup at the third quartile, 3.10 (95% CI, 0.60-15.84) in the subgroup at the second quartile, and 3.95 (95% CI, 0.81-19.15) in the subgroup at the lowest quartile. After adjustment for age and sex, the subgroup in the third quartile still presented with a significantly higher risk (OR, 4.85; 95% CI, 1.02-22.99) of risk of malnutrition. Compared with the subgroup at the highest quartile of tongue pressure, the crude OR for all the subgroups in the lower three quartiles was 4.17 (95% CI, 0.96-18.04), showing borderline significance (p = 0.05). In conclusion, we found hints for an association between decreased tongue pressure and an increased risk of malnutrition in community-dwelling older individuals. Older people with suboptimal tongue pressure should undergo a thorough assessment of their nutritional status and swallowing function for the early identification of subclinical malnutrition and dysphagia.


Assuntos
Desnutrição , Língua/fisiopatologia , Idoso , Estudos Transversais , Feminino , Fragilidade/fisiopatologia , Humanos , Vida Independente , Masculino , Desnutrição/epidemiologia , Desnutrição/fisiopatologia , Estado Nutricional , Pressão , Fatores de Risco , Sarcopenia/fisiopatologia , Taiwan
11.
Cell Transplant ; 23(4-5): 541-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24816449

RESUMO

Stroke is one of the disorders for which clinically effective therapeutic modalities are most needed, and numerous ways have been explored to attempt to investigate their feasibilities. However, ischemic- or hemorrhagic-induced inflammatory neuron death causes irreversible injuries and infarction regions, and there are currently no truly effective drugs available as therapy. It is therefore urgent to be able to provide a fundamental treatment method to regenerate neuronal brain cells, and therefore, the use of stem cells for curing chronic stroke could be a major breakthrough development. In this review, we describe the features and classification of stroke and focus on the benefits of adipose tissue-derived stem cells and their applications in stroke animal models. The results show that cell-based therapies have resulted in significant improvements in neuronal behaviors and functions through different molecular mechanisms, and no safety problems have so far arisen after transplantation. Further, we propose a clinical possibility to create a homing niche by reducing the degree of invasive intracerebroventricular transplantation and combining it with continuous intravenous administration to achieve a complete cure.


Assuntos
Tecido Adiposo/citologia , Transplante de Células-Tronco , Células-Tronco/citologia , Acidente Vascular Cerebral/terapia , Animais , Diferenciação Celular , Doença Crônica , Humanos , Imunomodulação , Neovascularização Fisiológica , Fatores de Crescimento Neural/metabolismo , Células-Tronco/metabolismo
13.
Clin Endocrinol (Oxf) ; 62(4): 492-7, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15807882

RESUMO

OBJECTIVE: Leiomyoma and hyperprolactinaemia are both progesterone-dependent diseases. Hormone-related genes, such as the progesterone receptor (PGR), might be involved in their pathogenesis. DESIGN AND MEASUREMENTS: Subjects were divided into three groups: (i) leiomyoma (n = 120); (ii) hyperprolactinaemia (n = 101); (iii) normal controls (n = 140). We investigated the Alu (306-bp DNA) insertion in intron G of the PGR gene in all individuals. PGR gene polymorphisms [T1 (wild-type); T2 (PROGINS, with Alu insertion)] were determined by PCR and electrophoresis. Genotype and allele frequencies of the PROGINS in each group were detected and compared. RESULTS: We observed no significant difference of the PGR*T1/T2 genotypes and allele frequencies between leiomyoma and other two groups. The proportions of T1 homozygote/heterozygote/T2 homozygote in each group were (i) 90/8.3/1.7%; (ii) 84.2/9.9/5.9%; (iii) 92.9/6.4/0.7%. In contrast, a higher percentage of T2-related genotype and allele were noted in hyperprolactinaemic women compared to other two groups. The proportions of T1/T2 alleles in each group were: (i) 94.2/5.8%; (ii) 89.1/10.9%; (iii) 96.1/3.9%. CONCLUSIONS: The PROGIN*T2-related genotype and allele are related to a higher susceptibility to hyperprolactinaemia. The PROGINS polymorphism is not associated with leiomyoma development.


Assuntos
Elementos Alu , Hiperprolactinemia/genética , Receptores de Progesterona/genética , Adulto , Alelos , Povo Asiático , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Hiperprolactinemia/etnologia , Leiomioma/etnologia , Leiomioma/genética , Polimorfismo Genético , Taiwan , Neoplasias Uterinas/etnologia , Neoplasias Uterinas/genética
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