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1.
J Am Acad Dermatol ; 81(5): 1176-1180, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31255749

RESUMO

BACKGROUND: Artificial intelligence methods for the classification of melanoma have been studied extensively. However, few studies compare these methods under the same standards. OBJECTIVE: To seek the best artificial intelligence method for diagnosis of melanoma. METHODS: The contrast test used 2200 dermoscopic images. Image segmentations, feature extractions, and classifications were performed in sequence for evaluation of traditional machine learning algorithms. The recent popular convolutional neural network frameworks were used for transfer learning training classification. RESULTS: The region growing algorithm has the best segmentation performance, with an intersection over union of 70.06% and a false-positive rate of 17.67%. Classification performance was better with logistic regression, with a sensitivity of 76.36% and a specificity of 87.04%. The Inception V3 model (Google, Mountain View, CA) worked best in deep learning algorithms: the accuracy was 93.74%, the sensitivity was 94.36%, and the specificity was 85.64%. LIMITATIONS: There was no division in the severity of melanoma samples used in this experiment. The data set was relatively small for deep learning. CONCLUSION: The performance of traditional machine learning is satisfactory for the small data set of melanoma dermoscopic images, and the potential for deep learning in the future big data era is enormous.


Assuntos
Inteligência Artificial , Melanoma/patologia , Neoplasias Cutâneas/patologia , Dermoscopia , Humanos , Melanoma/classificação , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias Cutâneas/classificação
2.
Dermatol Surg ; 37(10): 1480-5, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21790845

RESUMO

BACKGROUND: The Q-switched alexandrite laser (QSAL) has been clinically proven to be effective in treating nevus of Ota, but a large-scale retrospective study with long-term follow-up has never been performed. OBJECTIVE: To evaluate the efficacy of the QSAL in treating nevus of Ota, the laser's long-term side effects, complications associated with the treatments, and the recurrence rate. MATERIALS AND METHODS: Eight hundred six patients (651 female, 155 male) with a diagnosis of nevus of Ota who had received a series of QSAL (wavelength 755 nm) treatments were recruited. The typical settings were fluences of 3.8 to 4.8 J/cm(2) and a spot size of 3 mm. Follow-ups were conducted via questionnaire with 590 patients who had completed the treatment at least 3 years earlier. RESULTS: Overall, 93.9% of patients achieved complete clearance after an average of 5.2 sessions. All recurrences (0.8%) appeared beyond the previously treated sites. No long-term adverse effects, including hypopigmentation, hyperpigmentation, textural changes, and malignant transformation, were observed. CONCLUSION: The QSAL is a safe and effective modality for treating nevus of Ota. Recurrence was rare and appeared beyond the previously treated sites. The authors have indicated no significant interest with commercial supporters.


Assuntos
Neoplasias Faciais/terapia , Lasers de Estado Sólido/uso terapêutico , Terapia com Luz de Baixa Intensidade , Nevo de Ota/radioterapia , Neoplasias Cutâneas/radioterapia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Lasers de Estado Sólido/efeitos adversos , Terapia com Luz de Baixa Intensidade/efeitos adversos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
3.
J Invest Dermatol ; 131(5): 1129-38, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21326296

RESUMO

Frequent somatic mutations of BRAF (v-raf murine sarcoma viral oncogene homolog B) exon T1799A, which are implicated in the initial events of promutagenic cellular proliferation, are detected in both malignant melanomas (MM) and melanocytic nevi (MN). Most of the data regarding BRAF exon T1799A mutation have been from Caucasian cohorts, and a comprehensive screening of a homogeneous population is lacking. A total of 379 cases of MN and 195 cases of MM were collected from Chinese Han living in three geographical regions in China, i.e., northeast, southwest, and northwest China. BRAF exon T1799A mutation was detected by PCR and sequencing from microdissected tumors. In all, 59.8% cases of MN harbored BRAF exon T1799A mutation. Samples from regions with high UV exposure had higher detection rates than regions with lower UV exposure (73.5, 67.0, and 38.9%, respectively; χ(2) = 31.674, P = 1.59E-7). There were no differences in mutation rates between congenital and acquired MN; however, acquired MN with advanced age of onset had a higher mutation rate than those with younger age of onset (χ(2) = 13.23, P = 0.02). In all, 15.0% cases of MM harbored the BRAF mutation. The mutation rate in MM was not affected by region, histological type, gender, pattern of UV exposure, and age. The study suggests that the mutation is not necessarily associated with malignant transformation.


Assuntos
Éxons/genética , Melanoma/genética , Mutação/genética , Nevo Pigmentado/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genética , Adolescente , Adulto , Povo Asiático/genética , Povo Asiático/estatística & dados numéricos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Melanoma/epidemiologia , Nevo Pigmentado/epidemiologia , Prevalência , Estudos Retrospectivos , Neoplasias Cutâneas/epidemiologia , Raios Ultravioleta/efeitos adversos , Adulto Jovem
5.
J Cosmet Laser Ther ; 12(6): 250-5, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21142731

RESUMO

BACKGROUND AND OBJECTIVES: The ablative fractional CO2 laser has been successfully used in treating photoaged skin in the Caucasian population. However, its application in Asian skin has not been widely reported. The purpose of this study is to observe the efficacy and safety of the protocol 'ActiveFX' for photodamaged facial skin in Chinese patients. METHODS: A non-sequential fractional ultrapulsed CO2 laser with specific settings is used in addition to a new computer pattern generator (CPG). Twenty patients received a single-session, single-pass, ablative fractional treatment on a split face. The patients were evaluated at baseline, and 1 and 3 months (M1, M3) after the treatment using a quartile grading scale. They were also asked to assess their overall satisfaction using a 4-point scale. The improvement of the coarse wrinkles was also quantitatively analyzed with a 3D in vivo imaging system. RESULTS: At M1 and M3, the blinded investigator rated global improvement as 2.8 ± 0.95 and 3.00 ± 0.73, which was consistent with the patients' assessment (2.55 ± 0.83 at M1 and 3.15 ± 0.88 at M3). The roughness analysis (Rz) demonstrated a significant decrease in periorbital wrinkles (p < 0.0001). Minimal and reversible adverse side effects and rapid healing were noted. CONCLUSIONS: Non-sequential fractional ultrapulsed CO2 laser resurfacing (ActiveFX) is considered an excellent treatment modality for photodamaged Chinese facial skin.


Assuntos
Povo Asiático , Terapia a Laser , Lasers de Gás , Envelhecimento da Pele/efeitos da radiação , Adulto , China , Fracionamento da Dose de Radiação , Face , Feminino , Humanos , Pessoa de Meia-Idade , Satisfação do Paciente , Distribuição Aleatória , Rejuvenescimento
7.
Lasers Surg Med ; 42(2): 185-91, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20166160

RESUMO

BACKGROUND AND OBJECTIVES: Intense pulsed light (IPL) is regarded as the gold standard of nonablative photo-rejuvenation. Yet there is still a need to observe its efficacy and safety on dark skin using a split-face module. STUDY DESIGN/MATERIALS AND METHODS: Twenty-four Chinese women with photoaging were enrolled in this study. Patients were randomized to receive four IPL treatments at 3- to 4-week intervals on one side of face, with the other side spared as control. Changes of photoaging were evaluated using a global evaluation, an overall self-assessment, a Mexameter and a Corneometer. Skin biopsies were taken after four sessions of treatment on one side of face. The melanocyte density and the contents of melanin, collagen fibers, and elastic fibers were stained and used to evaluate the improvement on dyschromia and other signs of photoaging. RESULTS: The global scores of photoaging on treated side decreased significantly from 3.02 to 1.22, while it remained unchanged on the untreated side. Twenty-one of 24 patients (87.5%) rated their improvement as excellent or good. The difference on the values of melanin index and erythema index on treated side were significantly larger than those on untreated side after the 1st session, the 4th session and at 3-month follow-up (P<0.05). The melanin contents were significantly decreased and the collagen fibers were obviously increased only on treated side (P<0.05). Adverse effects of treated side were limited to mild pain and transient erythema. CONCLUSION: Using this split-face module, IPL treatment is proved both clinically and histologically to be effective in treating photoaging skin in Chinese population. Adverse effects were minimal and acceptable.


Assuntos
Povo Asiático , Terapia com Luz de Baixa Intensidade/métodos , Rejuvenescimento , Envelhecimento da Pele/patologia , Envelhecimento da Pele/efeitos da radiação , Adulto , China , Estética , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Lasers , Pessoa de Meia-Idade , Satisfação do Paciente , Probabilidade , Medição de Risco , Envelhecimento da Pele/etnologia , Estatísticas não Paramétricas , Resultado do Tratamento
8.
Phytother Res ; 23(6): 868-73, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19107739

RESUMO

Because of the central role of transcription factor nuclear factor-kappaB (NF-kappaB) in cell survival and proliferation in human multiple myeloma, the possibility of using it as a target for myeloma treatment was explored using genistein, an agent known to have very little or no toxicity in humans. It was found that NF-kappaB was constitutively active in two human myeloma cell lines examined and that genistein, a chemopreventive agent, down-regulated NF-kappaB in two cell lines as indicated by the electrophoretic mobility gel shift assay and prevented the nuclear retention of p65 as shown by immunocytochemistry. Two myeloma cell lines showed constitutively active Akt phosphorylation. Genistein suppressed the constitutive Akt phosphorylation. Genistein also down-regulated the expression of NF-kappaB-regulated gene products, including bcl-2, bcl-xl, cyclin D1 and ICAM-1. This led to the suppression of proliferation and induction of apoptosis. Overall, the results indicate that genistein down-regulates NF-kappaB and phospho-Akt in human myeloma cells, leading to the suppression of proliferation and induction of apoptosis, thus providing the molecular basis for the treatment of myeloma patients with this pharmacologically safe agent.


Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Genisteína/farmacologia , NF-kappa B/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Regulação para Baixo , Humanos , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição RelA/metabolismo
9.
Dermatol Surg ; 34(5): 693-700; discussion 700-1, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18318729

RESUMO

BACKGROUND: Melasma is commonly seen in the Asian population. Traditional therapies are less effective and may cause adverse effects. OBJECTIVE: The objective was to study the efficacy and safety of a new intense pulsed light (IPL) device in the treatment of melasma in Chinese patients. METHODS: Eighty-nine women with melasma were enrolled in this open-labeled study. Subjects received a total of four IPL treatments at 3-week intervals. Changes in facial hyperpigmentation and telangiectasis were evaluated using an objective, skin colorimeter (Mexameter, Courage & Khazaka), the melasma area and severity index (MASI), and a global evaluation by the patients and blind investigators. RESULTS: Sixty-nine of 89 patients (77.5%) obtained 51% to 100% improvement, according to the overall evaluation by dermatologists. Self-assessment by the patients indicated that 63 of 89 patients (70.8) considered more than 50% or more improvement. Mean MASI scores decreased substantially from 15.2 to 4.5. Mexameter results demonstrated a significant decrease in the degree of pigmentation and erythema beneath the melasma lesions. Patients with the epidermal-type melasma responded better to treatment than the mixed type. Adverse actions were minimal. CONCLUSION: IPL treatment is a good option for patients with melasma. Adverse actions of IPL were minimal and acceptable.


Assuntos
Melanose/terapia , Fototerapia/métodos , Adulto , Fatores Etários , Povo Asiático , Feminino , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento
10.
Dermatol Surg ; 31(3): 281-6, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15841627

RESUMO

BACKGROUND: Topical anesthetics are important tools for many dermatologic procedures. The S-Caine Peel is composed of a 1:1 (w:w) eutectic mixture composed of lidocaine base 7%, USP, and tetracaine base 7%, USP. It is applied as a cream, dries on exposure to air, and forms a flexible membrane, which can be easily peeled off. OBJECTIVE: To evaluate the effectiveness of the S-Caine Peel in providing clinically useful local dermal anesthesia for laser-assisted tattoo removal and to monitor the nature and frequency of adverse events associated with the safety of the S-Caine Peel. METHODS: Thirty adult patients undergoing laser-assisted tattoo removal were enrolled in this multicentered, randomized, double-blind, placebo-controlled study. Each subject received both the S-Caine Peel and placebo simultaneously for 60 minutes. The primary efficacy parameter was a 100 mm visual analog scale (VAS) for patient self-assessment of pain. Secondary efficacy parameters included both the investigator's and an independent observer's evaluation of subject pain (4-point categorical scale: no pain through severe pain) and the patient's and the investigator's overall impression of the local anesthetic. RESULTS: Mean VAS scores were 42 mm for the S-Caine Peel and 66 mm for placebo treatment sites (p=.001). Patients received adequate pain relief in 50% of S-Caine Peel sites versus 7% of placebo sites (p=.002). The percentage of those who would like to use the S-Caine Peel again were 43% for the S-Caine Peel compared with 7% for placebo (p=.005). Investigators' evaluations revealed that 70% of patients had less pain at S-Caine Peel treatment sites compared with 10% with less pain at placebo sites (p<.001), and 70% of the S-Caine Peel-treated sites achieved adequate anesthesia versus 10% of placebo sites (p<.001). The independent witness assessed less pain in 67% of S-Caine Peel-treated sites versus 10% of the placebo sites (p=.002). One occurrence of moderate to severe erythema was noted at both an S-Caine Peel and a placebo treatment site on removal of the S-Caine Peel after 60 minutes, which self-resolved quickly. There was no statistical difference between the two groups. Other side effects were limited to local mild, transient erythema at the application sites. CONCLUSION: Administration of the S-Caine Peel for 60 minutes prior to laser-assisted tattoo removal was effective in significantly reducing pain levels associated with the procedure.


Assuntos
Anestésicos Locais , Terapia a Laser , Lidocaína/administração & dosagem , Tatuagem , Tetracaína/administração & dosagem , Administração Tópica , Adulto , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Humanos , Masculino , Dor/prevenção & controle
11.
Dermatol Surg ; 29(10): 1012-8, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12974697

RESUMO

BACKGROUND: Topical anesthetics are valuable tools for many dermatologic procedures. OBJECTIVE: To evaluate the efficacy and safety of S-Caine Peel composed of 1:1 (wt:wt) mixture of 7% lidocaine and 7% tetracaine in the induction of local anesthesia before long-pulsed Nd:YAG laser therapy for leg veins. METHODS: Two randomized, double-blinded, placebo-controlled trials were performed. In study 1, 60 adults received S-Caine Peel and placebo cream for 30 or 60 minutes. Efficacy was evaluated by a patient visual analog scale and impression. The pain scale and impression were evaluated by the investigator and an independent observer. In study 2, 40 adults received 60- and 90-minute applications. RESULTS: In study 1, the 30- and 60-minute application times were grouped: Patients had adequate pain relief in 48% of S-Caine sites versus 23% of placebo sites (P<0.001). Investigators reported none-to-mild pain in 50% of active sites versus 33% of placebo sites (P=0.007), with adequate anesthesia in 65% of active sites versus 43% of placebo sites (P=0.002). The independent witness assessed none-to-mild pain in 52% of active sites versus 37% of placebo sites (P=0.067). In study 2, investigators rated none-to-mild pain in 75% of 60-minute and 85% of 90-minute S-Caine sites versus 30% and 50% of placebo sites (P=0.012 and P=0.002, respectively), with adequate anesthesia in 70% and 85% of 60- and 90-minute of active sites versus 25% and 20% of placebo sites (P=0.029 and P=0.001, respectively). The independent witness rated none to mild pain in 80% and 85% of 60 and 90 minute of S-Caine sites versus 35% and 50% of placebo sites (P=0.008 and P=0.004). CONCLUSION: The S-Caine Peel provides safe and highly effective local anesthesia when applied for at least 60 minutes for laser therapy of leg veins. Facile removal of the peel provides a unique advantage and ease in administration.


Assuntos
Anestésicos Locais/administração & dosagem , Terapia a Laser/efeitos adversos , Lidocaína/administração & dosagem , Dor/prevenção & controle , Tetracaína/administração & dosagem , Doenças Vasculares/cirurgia , Administração Tópica , Adulto , Método Duplo-Cego , Combinação de Medicamentos , Humanos , Perna (Membro)/cirurgia , Dor/etiologia , Fatores de Tempo , Resultado do Tratamento
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