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1.
CEN Case Rep ; 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38277067

RESUMO

Occasionally, patients undergoing dialysis develop acute severe hypotension that requires interruption of dialysis within minutes of initiating every dialysis session. Although the underlying causes of recurrent intradialytic hypotension are evaluated extensively, including dialysis-associated allergic reactions or other possible causes, the definitive cause is sometimes missed. Dialysis is a life-sustaining procedure; therefore, prompt identification and management of the underlying cause of dialysis intolerance are crucial. Herein, we report three cases of patients undergoing dialysis who presented with hypereosinophilia-associated acute intradialytic hypotension. All three patients developed acute severe hypotension within minutes after the start of every dialysis session. The prescriptions for dialysis were changed, but episodes of intradialytic hypotension persisted. Pretreatment with methylprednisolone given intravenously before the dialysis session was also ineffective. All patients had hypereosinophilia (> 1500/µL) of different etiology. Eosinophil-lowering therapy with 0.5 mg/kg of prednisolone given orally daily was initiated, and all of them could restart dialysis without any hypotensive episodes within a few days. Our case report and literature review indicated that hypereosinophilia, regardless of its etiology, could result in severe acute hypotension shortly after the start of dialysis session. The oral administration of prednisolone daily was highly effective on hypereosinophilia-associated intradialytic hypotension, while pretreatment with intravenous corticosteroid therapy just before dialysis had no effect. Hypereosinophilia-associated acute intradialytic hypotension is an under-recognized condition; therefore, clinicians need to be aware of this clinical entity and initiate effective treatment strategies. We also provide a brief summary of previously published cases.

2.
Breast Cancer ; 31(2): 228-233, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38012337

RESUMO

OBJECTIVE: Various efforts have been made to improve the accuracy of breast cancer screening. This study aimed to report differences in the contribution of ultrasonography to cancer screening assessments of dense and non-dense breasts. METHODS: The participants in this study were 29,640 Japanese women in their 40 s who underwent breast cancer screening at the Iwate Cancer Society between 2018 and 2021. This included women who chose mammography alone or mammography with adjunctive ultrasonography (overall assessment). They were classified into two groups according to the breast density in mammography: dense breasts and non-dense breasts. Recall rate, breast cancer detection rate, and positive predictive value of the two screening-type groups were evaluated for each breast density group. RESULTS: Of the 29,640 women analyzed, 18,861 (63.6%) underwent mammography alone and 10,779 (36.3%) were by overall assessments. The number of women recalled was higher in the overall assessment group than in the mammography-alone group (2.9% vs. 1.9%, p < 0.01). The proportion of women in whom breast cancer was detected was higher in the overall assessment group than in the mammography-alone group (0.31% [n = 33] vs. 0.15% [n = 28], p < 0.01). For non-dense breasts, there were no significant differences in either the recall rate or the breast cancer detection rate between those who underwent mammography alone and those who underwent overall assessment. Conversely, for dense breasts, the recall rate after mammography alone was lower than that after overall assessment (1.8% vs. 3.8%, p < 0.01), and the breast cancer detection rate was higher after overall assessment than after mammography alone (0.40% vs. 0.18%, p < 0.01). CONCLUSION: We found the benefits of adjunctive ultrasonography with mammography to differ depending on breast density. This could be used to tailor the selection of screening modalities to individuals.


Assuntos
Densidade da Mama , Neoplasias da Mama , Feminino , Humanos , Neoplasias da Mama/diagnóstico por imagem , Ultrassonografia Mamária , Mamografia , Ultrassonografia , Detecção Precoce de Câncer , Programas de Rastreamento
3.
Exp Eye Res ; 237: 109719, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37951336

RESUMO

Presbyopia is caused by age-related lenticular hardening, resulting in near vision loss, and it occurs in almost every individual aged ≥50 years. The lens experiences mechanical pressure during for focal adjustment to change its thickness. As lenticular stiffening results in incomplete thickness changes, near vision is reduced, which is known as presbyopia. Piezo1 is a mechanosensitive channel that constantly senses pressure changes during the regulation of visual acuity, and changes in Piezo1 channel activity may contribute to presbyopia. However, no studies have reported on Piezo1 activation or the onset of presbyopia. To elucidate the relevance of Piezo1 activation and cross-linking in the development of presbyopia, we analysed the function of Piezo1 in the lens. The addition of Yoda1, a Piezo1 activator, induced an increase in transglutaminase 2 (TGM2) mRNA expression and activity through the extra-cellular signal-regulated kinase (ERK) 1/2 and c-Jun-NH2-terminal kinase1/2 pathways. In ex vivo lenses, Yoda1 treatment induced γ-crystallin cross-linking via TMG2 activation. Furthermore, Yoda1 eye-drops in mice led to lenticular hardening via TGM2 induction and activation in vivo, suggesting that Yoda1-treated animals could serve as a model for presbyopia. Our findings indicate that this presbyopia-animal model could be useful for screening drugs for lens-stiffening inhibition.


Assuntos
Canais Iônicos , Presbiopia , Camundongos , Animais , Canais Iônicos/metabolismo , Proteína 2 Glutamina gama-Glutamiltransferase , Esclerose , Transporte Biológico
4.
Int J Mol Sci ; 24(15)2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37569284

RESUMO

Adipose stem and progenitor cells (ASPCs) have been isolated from humans and animals for use in regenerative medicine and therapy. However, knowledge of ASPCs in other species is limited. Particularly, ASPCs in livestock are expected to enhance the fat content and meat composition. In this study, we isolated bovine ASPCs using cell surface markers. Specifically, we focused on ASPC markers in humans and experimental animals, namely CD26, CD146, and CD54. Stromal vascular fraction cells from bovine fat were separated using flow cytometry before primary culture. We evaluated the self-renewal and adipogenic potential of each fraction. We identified four cell populations: CD26-CD146+CD54+, CD26-CD146+CD54-, CD26-CD146-, and CD26+CD146-. Among them, the CD26-CD146+ fraction, particularly CD54+, demonstrated the properties of preadipocytes (PreAs), characterized by slow proliferation and a high adipogenic capacity. In conclusion, we could collect and characterize possible PreAs as CD26-CD146+CD54+ or CD26-CD146+CD54-, which are expected for in vitro bovine adipogenic assays in the future.


Assuntos
Dipeptidil Peptidase 4 , Células-Tronco , Humanos , Bovinos , Animais , Dipeptidil Peptidase 4/metabolismo , Diferenciação Celular , Antígeno CD146/metabolismo , Células-Tronco/metabolismo , Citometria de Fluxo , Obesidade/metabolismo , Tecido Adiposo/metabolismo
5.
Biosci Biotechnol Biochem ; 87(8): 890-897, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37156505

RESUMO

Taste is an essential factor for evaluating the quality of agricultural products. However, it is usually difficult to compare data acquired at different times or by different people because there is no invariant reference and because the evaluation methods are largely subjective. Here, we addressed these problems by developing a method for standardizing strawberry sourness and sweetness intensities using a taste sensor approach with a taste standard solution composed of sour and sweet compounds. This standard solution allows highly efficient sensor measurements because it contains the standard compounds citric acid and sucrose. In addition, we found that polyphenol destabilized the sensor response for strawberry sweetness, and its removal from the sample by appropriate treatment with polyvinylpolypyrrolidone allowed stable evaluation of the sweetness intensity. The taste sensor data obtained using this method were in good agreement with the chemical analysis values related to human sensory evaluation.


Assuntos
Fragaria , Paladar , Humanos , Paladar/fisiologia , Percepção Gustatória , Sacarose , Padrões de Referência
6.
Neurol Int ; 16(1): 33-61, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38251051

RESUMO

Recent discoveries suggest links between abnormalities in cell morphogenesis in the brain and the functional deficiency of molecules controlling signal transduction in glial cells such as oligodendroglia. Rnd2 is one such molecule and one of the Rho family monomeric GTP-binding proteins. Despite the currently known functions of Rnd2, its precise roles as it relates to cell morphogenesis and disease state remain to be elucidated. First, we showed that signaling through the loss of function of the rnd2 gene affected the regulation of oligodendroglial cell-like morphological differentiation using the FBD-102b cell line, which is often utilized as a differentiation model. The knockdown of Rnd2 using the clustered regularly interspaced palindromic repeats (CRISPR)/CasRx system or RNA interference was shown to slow morphological differentiation. Second, the knockdown of Prag1 or Fyn kinase, a signaling molecule acting downstream of Rnd2, slowed differentiation. Rnd2 or Prag1 knockdown also decreased Fyn phosphorylation, which is critical for its activation and for oligodendroglial cell differentiation and myelination. Of note, hesperetin, a citrus flavonoid with protective effects on oligodendroglial cells and neurons, can recover differentiation states induced by the knockdown of Rnd2/Prag1/Fyn. Here, we showed that signaling through Rnd2/Prag1/Fyn is involved in the regulation of oligodendroglial cell-like morphological differentiation. The effects of knocking down the signaling cascade molecule can be recovered by hesperetin, highlighting an important molecular structure involved in morphological differentiation.

7.
Am Ann Deaf ; 167(3): 286-302, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36314162

RESUMO

The study's purpose was to clarify the developmental characteristics of working memory in hard of hearing children on the basis of language ability and task variables. Eighty-three congenitally severely hard of hearing children in grades 3-9 attending Japanese elementary and junior high school were aggregated on the basis of grade and language ability into six groups and received verbal and nonverbal tasks to measure their working memory capacity. The results suggest that hard of hearing children's nonverbal working memory is less affected by language ability and develops slowly as the school year progresses, showing a developmental trend similar to that of hearing children. Verbal working memory showed differences between groups by language ability in all grades due to the influence of language ability underlying processing in the phonological loop, but the results suggest that significant improvement occurs during elementary school regardless of language ability.


Assuntos
Idioma , Memória de Curto Prazo , Criança , Humanos , Testes de Linguagem , Cognição , Audição
8.
J Imaging ; 8(5)2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35621889

RESUMO

Recent advances in depth measurement and its utilization have made point cloud processing more critical. Additionally, the human head is essential for communication, and its three-dimensional data are expected to be utilized in this regard. However, a single RGB-Depth (RGBD) camera is prone to occlusion and depth measurement failure for dark hair colors such as black hair. Recently, point cloud completion, where an entire point cloud is estimated and generated from a partial point cloud, has been studied, but only the shape is learned, rather than the completion of colored point clouds. Thus, this paper proposes a machine learning-based completion method for colored point clouds with XYZ location information and the International Commission on Illumination (CIE) LAB (L*a*b*) color information. The proposed method uses the color difference between point clouds based on the Chamfer Distance (CD) or Earth Mover's Distance (EMD) of point cloud shape evaluation as a color loss. In addition, an adversarial loss to L*a*b*-Depth images rendered from the output point cloud can improve the visual quality. The experiments examined networks trained using a colored point cloud dataset created by combining two 3D datasets: hairstyles and faces. Experimental results show that using the adversarial loss with the colored point cloud renderer in the proposed method improves the image domain's evaluation.

10.
J Atheroscler Thromb ; 29(2): 252-267, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33455974

RESUMO

AIM: We investigated the influence of weight change on concurrent changes in predicted cardiovascular disease (CVD) risk and individual CVD risk factors over time. METHODS: A total of 2,140 community-dwellers aged 40-74 years participated in both 2002 and 2007 health examinations. Obesity was defined as body mass index ≥ 25 kg/m2. Weight trajectories were classified as: "stable obese" (obese at both examinations), "obese to nonobese" (obese in 2002 but nonobese in 2007), "nonobese to obese" (nonobese in 2002 but obese in 2007), or "stable nonobese" (nonobese at both examinations). We compared changes in the model-predicted risk for CVD and individual CVD risk factors across weight-change categories. RESULTS: The predicted risk for CVD increased during 5 years in all groups; the increment in the predicted risk for CVD was smallest in the obese to nonobese participants and steepest in the nonobese to obese subjects. Compared with the stable obese participants, the obese to nonobese participants had greater favorable changes in waist circumferences, blood pressure, fasting plasma glucose, serum high-density lipoprotein cholesterol, serum triglycerides, and liver enzymes. For all these parameters, opposite trends were observed when comparing the nonobese to obese participants with the stable nonobese group. CONCLUSIONS: We demonstrated the favorable association of losing weight in obese people and avoiding excessive weight gain in nonobese people with global risk of future CVD and individual CVD risk factors in a real-world setting. The findings could improve behavioral lifestyle interventions that provide information on the health consequences of weight change at health checkups.


Assuntos
Doenças Cardiovasculares/epidemiologia , Obesidade/complicações , Aumento de Peso , Redução de Peso , Adulto , Idoso , Índice de Massa Corporal , Doenças Cardiovasculares/diagnóstico , Feminino , Fatores de Risco de Doenças Cardíacas , Humanos , Japão , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Obesidade/diagnóstico , Fatores de Tempo
11.
PLoS Pathog ; 17(10): e1009542, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34648602

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes the disease COVID-19 can lead to serious symptoms, such as severe pneumonia, in the elderly and those with underlying medical conditions. While vaccines are now available, they do not work for everyone and therapeutic drugs are still needed, particularly for treating life-threatening conditions. Here, we showed nasal delivery of a new, unmodified camelid single-domain antibody (VHH), termed K-874A, effectively inhibited SARS-CoV-2 titers in infected lungs of Syrian hamsters without causing weight loss and cytokine induction. In vitro studies demonstrated that K-874A neutralized SARS-CoV-2 in both VeroE6/TMPRSS2 and human lung-derived alveolar organoid cells. Unlike other drug candidates, K-874A blocks viral membrane fusion rather than viral attachment. Cryo-electron microscopy revealed K-874A bound between the receptor binding domain and N-terminal domain of the virus S protein. Further, infected cells treated with K-874A produced fewer virus progeny that were less infective. We propose that direct administration of K-874A to the lung could be a new treatment for preventing the reinfection of amplified virus in COVID-19 patients.


Assuntos
Anticorpos Antivirais/administração & dosagem , Antivirais/administração & dosagem , COVID-19 , Anticorpos de Domínio Único/administração & dosagem , Ligação Viral/efeitos dos fármacos , Administração Intranasal , Animais , Chlorocebus aethiops , Cricetinae , Modelos Animais de Doenças , Humanos , Mesocricetus , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/imunologia , Células Vero
12.
Chemistry ; 27(65): 16225-16231, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34549839

RESUMO

A stereogenic π-system based on dimer (2) and trimer (3) of [2.2]paracyclophane (PC) and biphenyl was prepared and its structural, photophysical, and chiroptical properties were investigated. X-ray analysis revealed that the quaterphenyl moieties in 2 adopt a double helical structure anchoring [2.2]PC from both sides. Furthermore, 3 forms a isosceles triangle structure with a large chiral cavity. A homodesmotic reaction using DFT calculations revealed that 2 has a larger strain energy than 3 owing to its highly twisted phenylene linkers. Electronic and circular dichroic (CD) spectra were recorded in CH2 Cl2 solution. The spectra of both 2 and 3 are similar, and their longest absorption band accompanying a remarkable Cotton effect is attributed to the transition from HOMO to LUMO, which is delocalized to the quaterphenyl moiety. These compounds exhibit fairly high fluorescence quantum yields (ϕ=0.70-0.83) and moderate dissymmetry factor (|gCPL |=1.6×10-3 ) in circularly polarized luminescence (CPL).

13.
Alzheimers Dement (Amst) ; 13(1): e12221, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34337134

RESUMO

INTRODUCTION: We aimed to develop a risk prediction model for incident dementia using predictors that are available in primary-care settings. METHODS: A total of 795 subjects aged 65 years or over were prospectively followed-up from 1988 to 2012. A Cox proportional-hazards regression was used to develop a multivariable prediction model. The developed model was translated into a simplified scoring system based on the beta-coefficient. The discrimination of the model was assessed by Harrell's C statistic, and the calibration was assessed by a calibration plot. RESULTS: During the follow-up period, 364 subjects developed dementia. In the multivariable model, age, female sex, low education, leanness, hypertension, diabetes, history of stroke, current smoking, and sedentariness were selected as predictors. The developed model and simplified score showed good discrimination and calibration. DISCUSSION: The developed risk prediction model is feasible and practically useful in primary-care settings to identify individuals at high risk for future dementia.

14.
Biosci Biotechnol Biochem ; 85(6): 1485-1491, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-33881472

RESUMO

Cyclic nigerosylnigerose (CNN) is a cyclic tetrasaccharide with properties distinct from those of other conventional cyclodextrins. We investigated the relative available energy of CNN in healthy humans. CNN digestibility was determined using brush border membrane vesicles from the small intestines of rats. CNN was not hydrolyzed by rat intestinal enzymes. To investigate breath hydrogen excretion, 13 human subjects were included in a double-blind cross-over, randomized, placebo-controlled study. The effects of CNN on hydrogen excretion were compared with those of a typical nondigestible, fermentable fructooligosaccharide (FOS). In the study participants, hydrogen excretion hardly increased upon CNN and was remarkably lower than for FOS. The available energy value was determined using the fermentability based on breath hydrogen excretion and was evaluated as 0 kcal/g for CNN. CNN was hardly metabolized and hence may be used as a low-energy dietary fiber.


Assuntos
Metabolismo Energético , Glucanos/metabolismo , Adulto , Testes Respiratórios , Método Duplo-Cego , Feminino , Fermentação , Humanos , Hidrogênio/metabolismo , Masculino
15.
J Org Chem ; 86(1): 1053-1064, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33253567

RESUMO

Herein, we report the synthesis of 1-(difluoromethyl)alkenes via a palladium-catalyzed reaction of difluoromethyl-substituted allylic phosphates with 1,3-dicarbonyl compounds using PdCl2(PPh3)2 as a precatalyst. 1,3-Dicarbonyl compounds attacked the γ-carbon with respect to the difluoromethyl group to afford their corresponding SN2'-type substitution products irrespective of the substitution pattern in the allylic phosphates. This regioselectivity has been ascribed to the electronic environment of the unsymmetrical π-allylpalladium intermediate using density functional theory (DFT) calculations. The reaction of difluoromethyl-substituted allylic phosphates with imides was also carried out using a different catalyst system composed of [PdCl(η3-allyl)]2 and di(diphenylphosphino)butane (dppb).

16.
Nutrients ; 12(10)2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33081125

RESUMO

Few studies have examined the association between the accumulation of unhealthy eating habits and the likelihood of obesity or central obesity in a general Japanese population. We examined this association in a sample of 1906 community-dwelling Japanese subjects (age: 40-74 years) who participated in a health check-up in 2014. A face-to-face questionnaire interview was conducted to collect information about three unhealthy eating habits, i.e., snacking, eating quickly, and eating late-evening meals. Obesity was defined as body mass index ≥25 kg/m2 and central obesity was defined as waist circumference ≥90 cm in men and ≥80 cm in women. The odds ratios (OR) were estimated by using a logistic regression analysis. Subjects with any one of the three eating habits had a significantly higher likelihood of obesity than those without that habit after adjusting for confounding factors. The multivariable-adjusted OR for obesity increased linearly with an increase in the number of accumulated unhealthy eating habits (p for trend < 0.001). Similar associations were observed for central obesity. Our findings suggest that modifying each unhealthy eating habit and avoiding an accumulation of multiple unhealthy eating habits might be important to reduce the likelihood of obesity.


Assuntos
Dieta Saudável , Comportamento Alimentar/fisiologia , Vida Independente , Obesidade/etiologia , Obesidade/prevenção & controle , Adulto , Idoso , Povo Asiático , Feminino , Humanos , Japão/epidemiologia , Masculino , Refeições , Pessoa de Meia-Idade , Obesidade/epidemiologia , Lanches , Inquéritos e Questionários , Circunferência da Cintura
17.
Hepatol Res ; 50(6): 763-769, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32153130

RESUMO

AIM: More than 1400 Japanese hemophiliacs acquired HIV infection around 1983 through contaminated blood products imported from the USA, most of whom also acquired hepatitis C virus (HCV) infection. To delineate the HCV genetic relations in HIV-coinfected hemophiliacs, we analyzed stocked plasma samples of the patients seen at the largest referral center for HIV care in Japan. METHODS: Hepatitis C virus full-genome sequences were amplified and determined using next-generation sequencing, and genotyping and phylogenetic analyses of these sequences were carried out. The results of these hemophiliacs were compared with those of previously studied HIV-coinfected Japanese non-hemophiliacs who had undergone similar analysis of HCV full-genome sequences. RESULTS: From 1997 to the end of 2017, 72 HIV-infected Japanese hemophiliacs regularly visited our outpatient clinic. Of these, 51 patients had detectable plasma HCV-RNA. The HCV full genome was successfully amplified and sequenced in 50 patients. Not only HCV genotypes 1b (28%) and 2a (6%), which are common in Japan, but also HCV genotypes 1a (32%) and 3a (22%) were identified at high frequency. A single case of intergenotypic recombinant form (2b/1a) and a single case of mixed infection (1a and 3a) were also identified. Each sequence derived from hemophiliacs was more than 0.05 genetic distance away from the other sequences in phylogenetic analysis. CONCLUSIONS: Various HCV genotypes were identified in Japanese hemophiliacs, a finding that reflects the HCV genotypic distribution in the USA. The genetic distance among them are the results of viral evolution in each patient plus HCV genetic diversity in the USA.

18.
Biosci Biotechnol Biochem ; 84(4): 824-831, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31852406

RESUMO

We examined the effect of isomaltodextrin (IMD), a soluble dietary fiber, on production of putrefactive products by intestinal bacteria using a tyrosine load test to measure phenol production in IMD-treated rats. We observed a significant increase in phenol and p-cresol concentrations in rats administered with only tyrosine, but not for rats co-administered tyrosine and IMD. To elucidate the mechanism of this effect, we analyzed the intestinal microbiota in each group and found that although IMD had no direct effect on the proportion of bacteria known to produce phenols, it did alter the balance of intestinal microbiota. The results suggested that changes in the intestinal microbiota composition reduced the metabolic capacity for tyrosine and in turn suppressed production of phenol or p-cresol, putrefactive products in the intestine.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Polissacarídeos/farmacologia , Tirosina/metabolismo , Animais , Ceco/metabolismo , Concentração de Íons de Hidrogênio , Masculino , Fenóis/metabolismo , Ratos , Ratos Wistar , Tirosina/administração & dosagem
19.
Gerontology ; 65(4): 397-406, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31096217

RESUMO

BACKGROUND: Androgen production following exercise has been suggested to contribute anabolic actions of muscle. However, the underlying mechanisms of the androgen receptor (AR) in androgen's action are still unclear. OBJECTIVE: In the present study, we examined androgen/AR-mediated action in exercise, especially for the suppression of myostatin, a potent negative regulator of muscle mass. METHODS: To examine the effects of exercise, we employed low-intensity exercise in mice and electric pulse stimulation (EPS) in C2C12 myotubes. Androgen production by C2C12 myotubes was measured by enzyme-linked immunosorbent assay. To block the action of AR, we pretreated C2C12 myotubes with flutamide. Quantitative real-time polymerase chain reaction was used to determine the expression levels of proteolytic genes including CCAAT/enhancer-binding protein delta (C/EBPδ), myostatin and muscle E3 ubiquitin ligases, as well as myogenic genes such as myogenin and PGC1α. The activation of 5'-adenosine-activated protein kinase and STAT3 was determined by Western blot analysis. RESULTS: Both mRNA and protein levels of AR significantly increased in skeletal muscle of low-intensity exercised mice and C2C12 myotubes exposed to EPS. Production of testosterone and dihydrotestosterone from EPS-treated C2C12 myotubes was markedly increased. Of interest, we found that myostatin was clearly inhibited by EPS, and its inhibition was significantly abrogated when AR was blocked by flutamide. To test how AR suppresses myostatin, we examined the effects of EPS on C/EBPδ because the promoter region of myostatin has several C/EBP recognition sites. C/EBPδ expression was decreased by EPS, and this decrease was negated by flutamide. IL-6 and phospho-STAT3 (pSTAT3) expression, the downstream pathway of myostatin, were decreased by EPS and this was also reversed by flutamide. Similar downregulation of C/EBPδ, myostatin, and IL-6 was seen in skeletal muscle of low-intensity exercised mice. CONCLUSIONS: Muscle AR expression and androgen production were increased by exercise and EPS treatment. As a mechanistical insight, it is suggested that AR inhibited myostatin expression transcriptionally by C/EBPδ suppression, which negatively influences IL-6/pSTAT3 expression and consequently contributes to the prevention of muscle proteolysis during exercise.


Assuntos
Proteína delta de Ligação ao Facilitador CCAAT/genética , Fibras Musculares Esqueléticas/metabolismo , Miostatina/genética , Condicionamento Físico Animal , Receptores Androgênicos/genética , Antagonistas de Androgênios/farmacologia , Animais , Proteína delta de Ligação ao Facilitador CCAAT/efeitos dos fármacos , Di-Hidrotestosterona/metabolismo , Estimulação Elétrica , Flutamida/farmacologia , Técnicas In Vitro , Interleucina-6/metabolismo , Camundongos , Fibras Musculares Esqueléticas/efeitos dos fármacos , Miogenina/efeitos dos fármacos , Miogenina/genética , Miostatina/efeitos dos fármacos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/efeitos dos fármacos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores Androgênicos/metabolismo , Fator de Transcrição STAT3/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Testosterona/metabolismo , Transcriptoma
20.
Arch Virol ; 164(5): 1297-1308, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30820667

RESUMO

We previously developed CCR5-tropic neutralization-resistant simian/human immunodeficiency virus (SHIV) strains and a rhesus macaque model of infection with these SHIVs. We induced the production of neutralizing antibodies (nAbs) against HIV-1 by infecting rhesus macaques with different neutralization-resistant SHIV strains. First, SHIV-MK1 (MK1) (neutralization susceptible, tier 1B) with CCR5 tropism was generated from SHIV-KS661 using CXCR4 as the main co-receptor. nAbs against parental-lineage and heterologous tier 2 viruses were induced by tier 1B virus (MK1) infection of the rhesus macaque MM482. We analyzed viral resistance to neutralization over time in MM482 and observed that the infecting virus mutated from tier 1B to tier 2 at 36 weeks postinfection (wpi). In addition, an analysis of mutations showed that N169D, K187E, S190N, S239, T459N (T459D at 91 wpi), and V842A mutations were present after 36 wpi. This led to the appearance of neutralization-resistant viral clones. In addition, MK1 was passaged in three rhesus macaques to generate neutralization-resistant SHIV-MK38 (MK38) (tier 2). We evaluated nAb production by rhesus macaques infected with SHIV-MK38 #818 (#818) (tier 2), a molecular clone of MK38. Neutralization of the parental lineage was induced earlier than in macaques infected with tier 1B virus, and neutralization activity against heterologous tier 2 virus was beginning to develop. Therefore, CCR5-tropic neutralization-resistant SHIV-infected rhesus macaques may be useful models of anti-HIV-1 nAb production and will facilitate the development of a vaccine that elicits nAbs against HIV-1.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , HIV-1/imunologia , Vírus da Imunodeficiência Símia/imunologia , Animais , Linhagem Celular , Células HEK293 , Humanos , Macaca mulatta , Doenças dos Macacos/imunologia , Doenças dos Macacos/virologia , Testes de Neutralização/métodos , Receptores CCR5/metabolismo , Receptores CXCR4/metabolismo
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