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1.
Nature ; 620(7975): 768-775, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37612392

RESUMO

Models of artificial intelligence (AI) that have billions of parameters can achieve high accuracy across a range of tasks1,2, but they exacerbate the poor energy efficiency of conventional general-purpose processors, such as graphics processing units or central processing units. Analog in-memory computing (analog-AI)3-7 can provide better energy efficiency by performing matrix-vector multiplications in parallel on 'memory tiles'. However, analog-AI has yet to demonstrate software-equivalent (SWeq) accuracy on models that require many such tiles and efficient communication of neural-network activations between the tiles. Here we present an analog-AI chip that combines 35 million phase-change memory devices across 34 tiles, massively parallel inter-tile communication and analog, low-power peripheral circuitry that can achieve up to 12.4 tera-operations per second per watt (TOPS/W) chip-sustained performance. We demonstrate fully end-to-end SWeq accuracy for a small keyword-spotting network and near-SWeq accuracy on the much larger MLPerf8 recurrent neural-network transducer (RNNT), with more than 45 million weights mapped onto more than 140 million phase-change memory devices across five chips.

2.
J Med Case Rep ; 17(1): 186, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37101309

RESUMO

BACKGROUND: Chromosome 5p partial monosomy (5p-syndrome) and chromosome 6p partial trisomy are chromosomal abnormalities that result in a variety of symptoms, but liver dysfunction is not normally one of them. Alagille syndrome (OMIM #118450) is a multisystem disorder that is defined clinically by hepatic bile duct paucity and cholestasis, in association with cardiac, skeletal, and ophthalmologic manifestations, and characteristic facial features. Alagille syndrome is caused by mutations in JAG1 on chromosome 20 or NOTCH2 on chromosome 1. Here, we report a preterm infant with karyotype 46,XX,der(5)t(5,6)(p15.2;p22.3) and hepatic dysfunction, who was diagnosed as having incomplete Alagille syndrome. CASE PRESENTATION: The Japanese infant was diagnosed based on the cardiac abnormalities, ocular abnormalities, characteristic facial features, and liver pathological findings. Analysis of the JAG1 and NOTCH sequences failed to detect any mutations in these genes. CONCLUSIONS: These results suggest that, besides the genes that are known to be responsible for Alagille syndrome, other genetic mutations also may cause Alagille syndrome.


Assuntos
Síndrome de Alagille , Lactente , Humanos , Recém-Nascido , Síndrome de Alagille/diagnóstico , Síndrome de Alagille/genética , Síndrome de Alagille/patologia , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismo , Recém-Nascido Prematuro , Cariótipo
3.
Theriogenology ; 176: 200-205, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34627050

RESUMO

In dairy cows, the efficacy of oxytocin treatment for preventing retained fetal membranes (RFM) is controversial. The physiological condition of cows associated with the calving process may affect the action of oxytocin. This study aimed to elucidate the difference in the efficacy of exogenous oxytocin treatment immediately after calving among cows that received various obstetric interventions. The calving ease was recorded using a score of 1-5, and assisted birth was defined as a score of 2 or more. Cows that required calving assistance (assisted, n = 28) due to delayed calving progression had a prolonged time from calving to expulsion of the fetal membrane (P < 0.01), and impaired reproductive performance compared to cows that did not receive calving assistance (unassisted, n = 78). The effect of oxytocin treatment was determined using cows that did not expel their fetal membrane within 3 h after calving. Cows were randomly divided into the control (unassisted, n = 41; assisted, n = 22) or oxytocin group (unassisted, n = 33; assisted, n = 10). Oxytocin (50 IU) was administered intramuscularly to the cows in the oxytocin group between 3 and 6 h after calving, while no treatment was administered in the control group. In cows with assisted birth, oxytocin administration accelerated placental expulsion (P < 0.05) and improved several reproductive parameters, such as the number of services until conception (P < 0.05) and the calving to conception intervals (P < 0.05) compared to the control group. On the other hand, oxytocin administration slightly accelerated placental expulsion (P < 0.05), but failed to improve fertility in cows with unassisted birth. The results indicate that the action of oxytocin varies depending on the calving situation of the cows. Oxytocin administration during the early postpartum period could prevent RFM and improve the decline in reproductive performance associated with calving assistance.


Assuntos
Doenças dos Bovinos , Placenta Retida , Animais , Bovinos , Membranas Extraembrionárias , Feminino , Fertilidade , Ocitocina/uso terapêutico , Placenta , Placenta Retida/tratamento farmacológico , Placenta Retida/prevenção & controle , Placenta Retida/veterinária , Período Pós-Parto , Gravidez , Reprodução
4.
Parkinsonism Relat Disord ; 64: 293-299, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31103486

RESUMO

OBJECTIVE: To present five new McLeod Syndrome (MLS) pedigrees with novel XK gene mutations, review the literature of this disorder, and discuss the typical and atypical clinical features noted with these new mutations. METHODS: This is a multi-center retrospective review of five MLS cases with novel gene mutations. Genotypic and phenotypic information has been obtained from each center. RESULTS: Five novel mutations are reported in this Case series. New clinical findings include prolonged asymptomatic elevated creatine kinase (CK) levels, vocal tics, presence of obstructive sleep apnea (OSA), and one patient of Vietnamese ethnicity. CONCLUSIONS: We expand on the clinical and genetic spectrum of MLS demonstrating the clinical variability of MLS.


Assuntos
Sistemas de Transporte de Aminoácidos Neutros/genética , Neuroacantocitose/genética , Neuroacantocitose/fisiopatologia , Adulto , Comorbidade , Creatina Quinase/sangue , Europa (Continente) , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Neuroacantocitose/sangue , Neuroacantocitose/epidemiologia , Linhagem , Estudos Retrospectivos , Apneia Obstrutiva do Sono/epidemiologia , Vietnã
5.
New Microbes New Infect ; 27: 4-6, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30505452

RESUMO

This study describes a patient who experienced hepatobiliary Mycobacterium avium infection associated with neutralizing anti-interferon gamma (IFN-γ) autoantibodies during treatment for disseminated M. avium disease. Hepatobiliary M. avium infection should be considered in jaundiced patients with neutralizing anti-IFN-γ autoantibodies, including those receiving antimycobacterial therapy for disseminated M. avium disease.

6.
Int J Tuberc Lung Dis ; 22(6): 695-703, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29862956

RESUMO

BACKGROUND: Little is known about the clinical characteristics and health-related quality of life (HQOL) of elderly patients with pulmonary Mycobacterium avium complex (pMAC) disease. OBJECTIVES: To evaluate HQOL using the 36-Item Short-Form Health Survey and St George's Respiratory Questionnaire (SGRQ) and to investigate the predictors of HQOL changes among elderly patients with pMAC disease. METHODS: This prospective cohort registry was conducted at Keio University Hospital, Tokyo, Japan, between May 2012 and July 2015 and included 84 patients with pMAC disease aged 75 years who had completed the HQOL questionnaire and 48 patients with pMAC disease who had been followed up and completed the HQOL questionnaire in cross-sectional and longitudinal analyses, respectively. RESULTS: In cross-sectional analyses, elderly patients with pMAC disease had significantly lower role-physical, general health, vitality, social functioning, role-emotional and role/social component scores than the general Japanese elderly population. Analysis of covariance revealed that patients with cavitary lesions had significantly worse physical functioning and SGRQ scores (P < 0.05). Longitudinal analysis showed that under-treatment, short duration of disease and positive sputum smear at baseline were predictors of worse HQOL at 12 months. CONCLUSIONS: Elderly patients with pMAC disease have reduced HQOL. Further large studies on HQOL are required to refine the use of this parameter in the treatment of these patients.


Assuntos
Pneumopatias/fisiopatologia , Complexo Mycobacterium avium/isolamento & purificação , Infecção por Mycobacterium avium-intracellulare/fisiopatologia , Qualidade de Vida , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Estudos Transversais , Feminino , Seguimentos , Hospitais Universitários , Humanos , Estudos Longitudinais , Pneumopatias/microbiologia , Masculino , Estudos Prospectivos , Inquéritos e Questionários , Tóquio
10.
Science ; 357(6354): 928-932, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28860386

RESUMO

NAD+ (oxidized form of NAD:nicotinamide adenine dinucleotide)-reducing soluble [NiFe]-hydrogenase (SH) is phylogenetically related to NADH (reduced form of NAD+):quinone oxidoreductase (complex I), but the geometrical arrangements of the subunits and Fe-S clusters are unclear. Here, we describe the crystal structures of SH in the oxidized and reduced states. The cluster arrangement is similar to that of complex I, but the subunits orientation is not, which supports the hypothesis that subunits evolved as prebuilt modules. The oxidized active site includes a six-coordinate Ni, which is unprecedented for hydrogenases, whose coordination geometry would prevent O2 from approaching. In the reduced state showing the normal active site structure without a physiological electron acceptor, the flavin mononucleotide cofactor is dissociated, which may be caused by the oxidation state change of nearby Fe-S clusters and may suppress production of reactive oxygen species.


Assuntos
Proteínas de Bactérias/química , Hidrogenase/química , NAD/química , Sítios de Ligação , Oxirredução , Conformação Proteica , Subunidades Proteicas/química , Solubilidade
11.
Bone Joint Res ; 6(7): 439-445, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28747338

RESUMO

OBJECTIVES: We have previously investigated an association between the genome copy number variation (CNV) and acetabular dysplasia (AD). Hip osteoarthritis is associated with a genetic polymorphism in the aspartic acid repeat in the N-terminal region of the asporin (ASPN) gene; therefore, the present study aimed to investigate whether the CNV of ASPN is involved in the pathogenesis of AD. METHODS: Acetabular coverage of all subjects was evaluated using radiological findings (Sharp angle, centre-edge (CE) angle, acetabular roof obliquity (ARO) angle, and minimum joint space width). Genomic DNA was extracted from peripheral blood leukocytes. Agilent's region-targeted high-density oligonucleotide tiling microarray was used to analyse 64 female AD patients and 32 female control subjects. All statistical analyses were performed using EZR software (Fisher's exact probability test, Pearson's correlation test, and Student's t-test). RESULTS: CNV analysis of the ASPN gene revealed a copy number loss in significantly more AD patients (9/64) than control subjects (0/32; p = 0.0212). This loss occurred within a 60 kb region on 9q22.31, which harbours the gene for ASPN. The mean radiological parameters of these AD patients were significantly worse than those of the other subjects (Sharp angle, p = 0.0056; CE angle, p = 0.0076; ARO angle, p = 0.0065), and all nine patients required operative therapy such as total hip arthroplasty or pelvic osteotomy. Moreover, six of these nine patients had a history of operative or conservative therapy for developmental dysplasia of the hip. CONCLUSIONS: Copy number loss within the region harbouring the ASPN gene on 9q22.31 is associated with severe AD. A copy number loss in the ASPN gene region may play a role in the aetiology of severe AD.Cite this article: T. Sekimoto, M. Ishii, M. Emi, S. Kurogi, T. Funamoto, Y. Yonezawa, T. Tajima, T. Sakamoto, H. Hamada, E. Chosa. Copy number loss in the region of the ASPN gene in patients with acetabular dysplasia: ASPN CNV in acetabular dysplasia. Bone Joint Res 2017;6:439-445. DOI: 10.1302/2046-3758.67.BJR-2016-0094.R1.

12.
13.
J Thromb Haemost ; 14(4): 850-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26773298

RESUMO

BACKGROUND: Accurate evaluation of thrombogenicity helps to prevent thrombosis and excessive bleeding. The total thrombus-formation analysis system (T-TAS) was developed for quantitative analysis of platelet thrombus formation by the use of microchips with thrombogenic surfaces (collagen, platelet chip [PL-chip]; collagen plus tissue factor, atherome chip [AR-chip]). We examined the utility of the T-TAS in the assessment of the efficacy of antiplatelet therapy in patients with coronary artery disease (CAD). METHODS AND RESULTS: In this cross-sectional study, 372 consecutive patients admitted to the cardiovascular department were divided into three groups: patients not receiving any antiplatelet therapy (control, n = 56), patients receiving aspirin only (n = 69), and patients receiving aspirin and clopidogrel (n = 149). Blood samples were used for the T-TAS to measure the platelet thrombus-formation area under the curve (AUC) at various shear rates (1500 s(-1) [PL18 -AUC10 ] and 2000 s(-1) [PL24 -AUC10 ] for the PL-chip; 300 s(-1) [AR10 -AUC30 ] for the AR-chip). The on-clopidogrel platelet aggregation was measured by the use of P2Y12 reaction units (PRUs) with the VerifyNow system. The mean PL24 -AUC10 levels were 358 ± 111 (± standard deviation) (95% confidence interval [CI] 328.9-387.1) in the control group, 256 ± 108 (95% CI 230.5-281.5) in the aspirin group, and 113 ± 91 (95% CI 98.4-127.6) in the aspirin/clopidogrel group. In the aspirin/clopidogrel group, the PL24 -AUC10 was higher in poor metabolizers (PMs) with cytochrome P450 2C19(CYP2C19) polymorphisms (152 ± 112, 95% CI 103.4-200.6) than in the non-PM group (87 ± 74, 95% CI 73.8-100.2). CONCLUSIONS: Our findings suggest that the PL24 -AUC10 level measured by the T-TAS is a potentially suitable index for the assessment of antiplatelet therapy in CAD patients.


Assuntos
Plaquetas/efeitos dos fármacos , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Idoso , Área Sob a Curva , Aspirina/administração & dosagem , Clopidogrel , Estudos Transversais , Citocromo P-450 CYP2C19/genética , Eletrocardiografia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Agregação Plaquetária , Inibidores da Agregação Plaquetária/sangue , Testes de Função Plaquetária , Polimorfismo Genético , Trombose/sangue , Trombose/tratamento farmacológico , Trombose/genética , Ticlopidina/administração & dosagem , Ticlopidina/análogos & derivados
14.
Ann Rev Mar Sci ; 8: 185-215, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26515811

RESUMO

Global ship-based programs, with highly accurate, full water column physical and biogeochemical observations repeated decadally since the 1970s, provide a crucial resource for documenting ocean change. The ocean, a central component of Earth's climate system, is taking up most of Earth's excess anthropogenic heat, with about 19% of this excess in the abyssal ocean beneath 2,000 m, dominated by Southern Ocean warming. The ocean also has taken up about 27% of anthropogenic carbon, resulting in acidification of the upper ocean. Increased stratification has resulted in a decline in oxygen and increase in nutrients in the Northern Hemisphere thermocline and an expansion of tropical oxygen minimum zones. Southern Hemisphere thermocline oxygen increased in the 2000s owing to stronger wind forcing and ventilation. The most recent decade of global hydrography has mapped dissolved organic carbon, a large, bioactive reservoir, for the first time and quantified its contribution to export production (∼20%) and deep-ocean oxygen utilization. Ship-based measurements also show that vertical diffusivity increases from a minimum in the thermocline to a maximum within the bottom 1,500 m, shifting our physical paradigm of the ocean's overturning circulation.


Assuntos
Carbono/análise , Água do Mar/química , Clima , Oceanografia/instrumentação , Navios , Temperatura , Movimentos da Água
15.
Artigo em Inglês | MEDLINE | ID: mdl-29225399

RESUMO

In this work we present a method for dense reconstruction of anatomical structures using white light endoscopic imagery based on a learning process that estimates a mapping between light reflectance and surface geometry. Our method is unique in that few unrealistic assumptions are considered (i.e., we do not assume a Lambertian reflectance model nor do we assume a point light source) and we learn a model on a per-patient basis, thus increasing the accuracy and extensibility to different endoscopic sequences. The proposed method assumes accurate video-CT registration through a combination of Structure-from-Motion (SfM) and Trimmed-ICP, and then uses the registered 3D structure and motion to generate training data with which to learn a multivariate regression of observed pixel values to known 3D surface geometry. We demonstrate with a non-linear regression technique using a neural network towards estimating depth images and surface normal maps, resulting in high-resolution spatial 3D reconstructions to an average error of 0.53mm (on the low side, when anatomy matches the CT precisely) to 1.12mm (on the high side, when the presence of liquids causes scene geometry that is not present in the CT for evaluation). Our results are exhibited on patient data and validated with associated CT scans. In total, we processed 206 total endoscopic images from patient data, where each image yields approximately 1 million reconstructed 3D points per image.

16.
Proc SPIE Int Soc Opt Eng ; 94152015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25991876

RESUMO

We present a system for registering the coordinate frame of an endoscope to pre- or intra- operatively acquired CT data based on optimizing the similarity metric between an endoscopic image and an image predicted via rendering of CT. Our method is robust and semi-automatic because it takes account of physical constraints, specifically, collisions between the endoscope and the anatomy, to initialize and constrain the search. The proposed optimization method is based on a stochastic optimization algorithm that evaluates a large number of similarity metric functions in parallel on a graphics processing unit. Images from a cadaver and a patient were used for evaluation. The registration error was 0.83 mm and 1.97 mm for cadaver and patient images respectively. The average registration time for 60 trials was 4.4 seconds. The patient study demonstrated robustness of the proposed algorithm against a moderate anatomical deformation.

17.
Acta Neurochir Suppl ; 120: 167-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25366618

RESUMO

PURPOSE: We evaluated patients treated with prophylactic intra-arterial administration of fasudil hydrochloride (IAF) after subarachnoid haemorrhage (SAH). MATERIALS AND METHODS: Between August 1998 and December 2012, 92 patients with aneurysmal SAH were treated with IAF for angiographic vasospasm without ischemic symptoms after their follow-up angiography. Patients comprised 50 women and 42 men, aged 24-83 (mean 56.6) years. IAF consisted of 15 mg of fasudil hydrochloride dissolved in 20 ml physiological saline and injected through a catheter during approximately 15 min, after diagnostic angiography. The clinical outcome was evaluated using the Glasgow Outcome Scale (GOS) at discharge and ischemic lesions resulting from vasospasm were assessed on computed tomography (CT) scan at discharge. RESULTS: Forty-eight patients underwent surgical clipping and 44 patients underwent endovascular coiling. Angiographic improvement was observed in all patients (100 %). At discharge, 76 (83.0 %) of 92 patients showed good recovery on GOS. Nine patients developed progression of delayed ischemic neurological deficits (DIND) and three of these patients had ischemic lesions on CT scans. No patient had any significant changes in vital signs or any other adverse effects resulting from IAF. CONCLUSION: IAF therapy was safe and effective for patients with vasospasm following SAH. Prophylactic IAF therapy may prevent symptomatic vasospasm.


Assuntos
1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , Recuperação de Função Fisiológica/efeitos dos fármacos , Hemorragia Subaracnóidea/tratamento farmacológico , Vasodilatadores/administração & dosagem , Vasoespasmo Intracraniano/tratamento farmacológico , Vasoespasmo Intracraniano/prevenção & controle , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Embolização Terapêutica , Feminino , Seguimentos , Humanos , Injeções Intra-Arteriais , Masculino , Pessoa de Meia-Idade , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/cirurgia , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Vasoespasmo Intracraniano/cirurgia , Adulto Jovem
18.
Neurogastroenterol Motil ; 27(1): 82-91, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25428414

RESUMO

BACKGROUND: Serotonin type 3 receptor (5-HT3 R) antagonists are potentially useful therapeutic agents for diarrhea-predominant irritable bowel syndrome (IBS-D). To identify biomarkers predicting effectiveness of the 5-HT3 R antagonist (ramosetron) in IBS-D. METHODS: Irritable bowel syndrome-D Japanese subjects received 2.5 or 5 µg of ramosetron once daily for 4 weeks. Colonic mucosal S100A and tryptophan hydroxylase (TPH) mRNA expression levels were measured before treatment. Genomic DNA was extracted from blood and polymorphisms of TPH1 and TPH2 were analyzed. KEY RESULTS: Forty-two patients (27 men and 15 women, mean age 42 years) with IBS-D were included for analysis. Improvement of IBS symptoms was seen in 26 (61.9%). Baseline S100A10 (p = 0.02) and TPH1 (p = 0.02) expression were significantly higher in the ramosetron responders than in the non-responders. The frequencies of the TPH1 rs4537731G allele in linkage disequilibrium with the TPH1 rs7130929 T allele (11.5% vs 50%, p = 0.003; OR: 12; 95% CI: 2.1-69) along with TPH1 rs211105 C allele (3.8% vs 43.8%, p = 0.0003; OR: 19; 95% CI: 2.1-181) were significantly lower in the responders than in the non-responders. The mean scores of diarrhea at baseline were significantly higher (5.2 vs 3.7, p = 0.005) in patients with TPH1 rs211105 T/T than those with the G allele. CONCLUSIONS & INFERENCES: TPH1 gene polymorphisms and S100A10 expression, which correlate with 5-HT signaling were associated with ramosetron effectiveness in IBS-D, and may possibly lead to prospective identification of the resistance to treatment.


Assuntos
Anexina A2/metabolismo , Benzimidazóis/administração & dosagem , Biomarcadores Farmacológicos , Diarreia/tratamento farmacológico , Síndrome do Intestino Irritável/tratamento farmacológico , Proteínas S100/metabolismo , Antagonistas do Receptor 5-HT3 de Serotonina/administração & dosagem , Triptofano Hidroxilase/genética , Adulto , Diarreia/complicações , Feminino , Humanos , Mucosa Intestinal/metabolismo , Síndrome do Intestino Irritável/complicações , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Polimorfismo de Nucleotídeo Único , Resultado do Tratamento
19.
Bull Entomol Res ; 105(2): 152-65, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25499047

RESUMO

Zizina emelina (de l'Orza) is listed on Japan's Red Data List as an endangered species because of loss of its principal food plant and habitat. We compared parts of the mitochondrial and nuclear genes of this species to investigate the level of genetic differentiation among the 14 extant populations. We also examined infection of the butterfly with the bacterium Wolbachia to clarify the bacterium's effects on the host population's genetic structure. Mitochondrial and nuclear DNA analyses revealed that haplotype composition differed significantly among most of the populations, and the fixation index F ST was positively correlated with geographic distance. In addition, we found three strains of Wolbachia, one of which was a male killer; these strains were prevalent in several populations. There was linkage between some host mitochondrial haplotypes and the three Wolbachia strains, although no significant differences were found in a comparison of host mitochondrial genetic diversity with nuclear genetic diversity in Wolbachia-infected or -uninfected populations. These genetic analyses and Wolbachia infection findings show that Z. emelina has little migratory activity and that little gene flow occurs among the current populations.


Assuntos
Borboletas/genética , Borboletas/microbiologia , DNA Mitocondrial/química , Wolbachia/fisiologia , Animais , Espécies em Perigo de Extinção , Feminino , Variação Genética , Interações Hospedeiro-Patógeno , Japão , Masculino , Filogenia , Razão de Masculinidade
20.
Cell Death Dis ; 5: e1189, 2014 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-24763046

RESUMO

Obesity-related disorders are closely associated with the development of age-related hearing impairment (ARHI). Adiponectin (APN) exerts protective effects against obesity-related conditions including endothelial dysfunction and atherosclerosis. Here, we investigated the impact of APN on ARHI. APN-knockout (APN-KO) mice developed exacerbation of hearing impairment, particularly in the high frequency range, compared with wild-type (WT) mice. Supplementation with APN prevented the hearing impairment in APN-KO mice. At 2 months of age, the cochlear blood flow and capillary density of the stria vascularis (SV) were significantly reduced in APN-KO mice as compared with WT mice. APN-KO mice also showed a significant increase in terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive apoptotic cells in the organ of Corti in the cochlea at 2 months of age. At the age of 6 months, hair cells were lost at the organ of Corti in APN-KO mice. In cultured auditory HEI-OC1 cells, APN reduced apoptotic activity under hypoxic conditions. Clinically, plasma APN levels were significantly lower in humans with ARHI. Multiple logistic regression analysis identified APN as a significant and independent predictor of ARHI. Our observations indicate that APN has an important role in preventing ARHI.


Assuntos
Adiponectina/deficiência , Envelhecimento/patologia , Progressão da Doença , Perda Auditiva/metabolismo , Adiponectina/sangue , Adiponectina/metabolismo , Adiponectina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Limiar Auditivo/efeitos dos fármacos , Capilares/patologia , Linhagem Celular , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Células Ciliadas Auditivas/efeitos dos fármacos , Células Ciliadas Auditivas/patologia , Perda Auditiva/sangue , Perda Auditiva/patologia , Perda Auditiva/fisiopatologia , Humanos , Masculino , Camundongos Knockout , Pessoa de Meia-Idade , Órgão Espiral/irrigação sanguínea , Órgão Espiral/efeitos dos fármacos , Órgão Espiral/patologia , Órgão Espiral/fisiopatologia , Fluxo Sanguíneo Regional/efeitos dos fármacos
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