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2.
IEEE Trans Biomed Eng ; 71(4): 1161-1169, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37922169

RESUMO

Surface electromyography (sEMG) is currently the primary method for user control of prosthetic manipulation. Its inherent limitations of low signal-to-noise ratio, limited specificity and susceptibility to noise, however, hinder successful implementation. Ultrasound provides a possible alternative, but current systems with medical probes are expense, bulky and non-wearable. This work proposes an innovative prosthetic control strategy based on a piezoelectric micromachined ultrasound transducer (PMUT) hardware system. Two PMUT-based probes were developed, comprising a 23×26 PMUT array and encapsulated in Ecoflex material. These compact and wearable probes represent a significant improvement over traditional ultrasound probes as they weigh only 1.8 grams and eliminate the need for ultrasound gel. A preliminary test of the probes was performed in non-disabled subjects performing 12 different hand gestures. The two probes were placed perpendicular to the flexor digitorum superficialis and brachioradialis muscles, respectively, to transmit/receive pulse-echo signals reflecting muscle activities. Hand gesture was correctly predicted 96% of the time with only these two probes. The adoption of the PMUT-based strategy greatly reduced the required number of channels, amount of processing circuit and subsequent analysis. The probes show promise for making prosthesis control more practical and economical.


Assuntos
Membros Artificiais , Humanos , Ultrassonografia , Razão Sinal-Ruído , Transdutores , Extremidade Superior/diagnóstico por imagem
4.
Biochem Biophys Res Commun ; 515(2): 310-317, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31153635

RESUMO

The cutaneous squamous cell carcinoma (cSCC) originates from epithelial stem cells through the dysregulation of self-renewal and differentiation. Recent studies have identified methyltransferase-like 3 (METTL3)-mediated N6-methyladenosine (m6A) modification as key regulator of fate of stem cells. However, little is known about the functional importance of METTL3 in cSCC. Here, Western blot and immunohistochemistry were used to investigate the METTL3 levels in cSCC tissues. Functional experiments including surface marker detection, Brdu incorporation assay, colony forming assay, m6A dot blot and tumor xenograft assay were performed to investigate the properties in cSCC cell lines after METTL3 knock down. The expression of METTL3 was up-regulated in cSCC samples. METTL3 knock down impaired cSCC cell stem-like properties, including colony forming ability in vitro and tumorigenicity in vivo. Furthermore, METTL3 knock down and methylation inhibitor cycloleucine could decrease the m6A levels and the expression of ΔNp63 in cSCC. Exogenous expression of ΔNp63 partially restored the cell proliferation of METTL3-knockdown cSCC cells. Therefore, our data indicated the m6A methyltransferases METTL3 as a critical gene in regulating tumorigeneis of cSCC.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Metiltransferases/metabolismo , Neoplasias Cutâneas/metabolismo , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Adenosina/análogos & derivados , Adenosina/metabolismo , Animais , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/patologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Autorrenovação Celular/genética , Autorrenovação Celular/fisiologia , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Metiltransferases/antagonistas & inibidores , Metiltransferases/genética , Camundongos , Camundongos Nus , Processamento Pós-Transcricional do RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética
5.
Pediatr Res ; 83(1-1): 175-182, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29019471

RESUMO

BackgroundPropranolol is the first-choice treatment for severe infantile hemangioma (IH). However, 10- 30% of lesions relapse after propranolol treatment. The mechanisms underlying IH recurrence after propranolol treatment have not been completely elucidated.MethodsThis study combined an examination of hemodynamic changes with research regarding hemangioma stem cells (hscs) with differentially expressed microRNAs (miRNAs) to identify the factors affecting IH recurrence after propranolol treatment. Hemodynamic changes were monitored in 21 recurrent cases using high-frequency color Doppler ultrasound, and hscs were treated with different concentrations of propranolol. The levels of differentially expressed miRNAs and the activity of related pathways were then compared between 18 recurrent and 20 non-recurrent IH cases.ResultsDuring treatment, lesion depth and vessel density decreased, and the lesion resistance index increased. Obvious lesions and vessel signals were observed in recurrent cases compared with non-recurrent cases. Propranolol effectively inhibited hscs proliferation. Twenty-two differentially expressed miRNAs were found in the recurrent group compared with the non-recurrent group.ConclusionRecurrence may be attributed to a combination of events. Serum biomarkers and drug treatments for IH recurrence must be studied further.


Assuntos
Hemangioma/diagnóstico , Hemangioma/fisiopatologia , Propranolol/uso terapêutico , Recidiva , Biomarcadores/sangue , Feminino , Hemodinâmica , Humanos , Lactente , Recém-Nascido , Masculino , MicroRNAs/metabolismo , Ultrassonografia Doppler , Vasoconstrição
6.
J Med Ultrason (2001) ; 44(3): 275-278, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28224305

RESUMO

Diagnosis and monitoring of early high-flow vascular malformations could be a meaningful pursuit. However, there has been no ideal method for their long-term monitoring and prognosis. We examined 21 early high-flow vascular malformations in this study and deemed that high-frequency color Doppler ultrasound could be regarded as the first diagnostic and monitoring choice for early high-flow vascular malformations at present.


Assuntos
Monitorização Hemodinâmica , Ultrassonografia Doppler em Cores , Malformações Vasculares/diagnóstico por imagem , Nádegas/irrigação sanguínea , Nádegas/diagnóstico por imagem , Pré-Escolar , Diagnóstico Diferencial , Face/irrigação sanguínea , Face/diagnóstico por imagem , Feminino , Monitorização Hemodinâmica/métodos , Humanos , Lactente , Masculino , Fluxo Sanguíneo Regional
7.
Head Neck ; 38 Suppl 1: E1730-6, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26676449

RESUMO

BACKGROUND: Few specific reports have addressed propranolol as a treatment for parotid hemangioma, and its mechanism remains unclear. METHODS: Eighty-seven patients were recruited in this prospective study. Ten patients underwent detailed color Doppler examination. The depths, vessel densities, and resistant indices of 10 lesions were recorded and analyzed before treatment and at 1 and 3 months after treatment. RESULTS: The overall responses were "bad" in 2 cases, "stable" in 4 cases, "good" in 53 cases, and "excellent" in 28 cases. Hemangioma regrowth was observed in 11 cases (12.6%). The parents of 18 patients (20.7%) complained that their children experienced minor discomfort during therapy. The lesion depths, vessel densities, and resistant indices were altered after propranolol treatment. CONCLUSION: Propranolol can significantly reduce the sizes of parotid hemangiomas with minor side effects. Hemodynamic changes might play an important role in the course of propranolol treatment. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1730-E1736, 2016.


Assuntos
Hemangioma/tratamento farmacológico , Neoplasias Parotídeas/tratamento farmacológico , Propranolol/uso terapêutico , Administração Oral , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Recidiva Local de Neoplasia , Estudos Prospectivos , Resultado do Tratamento
8.
Tumour Biol ; 37(2): 2765-71, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26408183

RESUMO

Cutaneous squamous cell carcinoma (cSCC) is an epidermal keratinocyte-derived skin tumor, which is the second most common skin cancer in the general population. Recently, studies showed that microRNAs (miRNAs) played an important role in the development of cancer. In our study, we showed that the expression of SRCIN1 was lower in cSCC tissues than in the matched normal tissues. Moreover, there was significant inversed correlation between miR-346 and SRCIN1 in cSCC tissues. The luciferase reporter assay data showed that miR-346 can target the SRCIN1 message via the 3'-untranslated region (UTR) of SRCIN1. Overexpression of miR-346 inhibited the messenger RNA (mRNA) and protein expression of SRCIN1 in the A431 cells. In addition, ectopic expression of miR-346 promoted the A431 cell proliferation and migration. Meanwhile, SRCIN1 overexpression inhibited the A431 cell proliferation and migration. Rescue experiment has showed that SRCIN1 overexpression reduced the miR-346-induced A431 cell proliferation and migration. Herein, this study may provide miR-346 as a new therapeutic target for cSCC.


Assuntos
Carcinoma de Células Escamosas/genética , MicroRNAs/genética , Oncogenes/genética , Neoplasias Cutâneas/genética , Regiões 3' não Traduzidas/genética , Proteínas Adaptadoras de Transporte Vesicular/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Queratinócitos/patologia , RNA Mensageiro/genética , Neoplasias Cutâneas/patologia
9.
Ann Plast Surg ; 76(5): 559-63, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26101993

RESUMO

BACKGROUND: The protocol for the treatment of infantile hemangioma with propranolol varies among different clinical centers. METHODS: Six hundred seventy-nine patients who were 1 to 12 months old were recruited in this prospective study to receive propranolol treatment. The response to the propranolol therapy was classified as 4 levels. The results were primarily evaluated using color Doppler ultrasound examinations before and after propranolol treatment. RESULTS: The response was excellent in 176 (25.9%), good in 492 (72.5%), stable in 5 (0.7%), and poor in 6 (0.9%) of the patients. The mean age at the initiation of the therapy was 3.3 months (range, 1 to 10.9 months) and the mean duration of the therapy was 7.1 months (range, 3-17 months). The mean duration of the follow-up time after the discontinuation of the therapy was 5.3 months (range, 3-17 months). Regrowth of the hemangioma was observed in 92 cases (13.5%). Seventy-nine (11.6%) of the parents complained of their child's minor discomfort during the therapy. CONCLUSIONS: Propranolol (2 mg/kg per day) may significantly reduce the size of a hemangioma. As an outpatient therapy, propranolol was found to be safe for Chinese children and to have minor side effects.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Assistência Ambulatorial , Hemangioma Capilar/tratamento farmacológico , Propranolol/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , China , Feminino , Seguimentos , Hemangioma Capilar/diagnóstico por imagem , Humanos , Lactente , Masculino , Estudos Prospectivos , Neoplasias Cutâneas/diagnóstico por imagem , Resultado do Tratamento , Ultrassonografia Doppler
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