Blue Nevus Hidden within the Nevus of Ota

A 3-year-old boy presented with bluish patch and scattered blue spots on the left side of his face.After several sessions of laser treatment,the azury patch in the periorbital area became even darker.Histopathology showed many bipolar,pigment-laden dendritic cells scattered in the papillary and upper reticular dermis.Immunohistochemically,these cells were positive for S100,SOX-10,melan-A,P16,and HMB-45.The positive rate of Ki-67 was less than 5%.Finally,the lesion was diagnosed with nevus of Ota concurrent with common blue nevus.Therefore,for cases of the nevus of Ota with poor response to laser treatment,the possible coexisting diseases should be suspected.

Intracranial Intermediate-Grade Melanocytic Neoplasm: Case Report Associated with Nevus of Ota

Melanocytic lesions of the CNS are rare tumours originating from melanocytes that are present in the leptomeninges. They consist of a spectrum of pigmented tumours ranging from melanocytoma to melanoma. A small group of these tumours have histopathological features between those of a benign melanocytoma and a malignant melanoma;these present as intermediate grade melanocytic neoplasms. Naevus of Ota is a blue hyperpigmented dermal lesion characterized by increased number of melanocytes in the distribution of ophthalmic and maxillary divisions of the trigeminal nerve. The association of an intracranial intermediate-grade melanocytic neoplasm with a nevus of Ota is extremely rare, with only 2 cases reported in the literature to date. As a result, their behavior and progression are still poorly understood. We present the first case of a familial naevus of Ota associated with intermediate-grade melanocytic neoplasm.

Imiquimod:A potential option for inhibition of repigmentation of congenital melanocytic nevus after laser ablation

Congenital melanocytic nevi(CMN) are common skin tumors. Large and specially located nevi cannot be completely removed by surgery, posing the risks of both cosmetic deformities and potential malignancy.Nonsurgical treatments, such as laser therapy and physical dermabrasion, can overcome the limitations of surgery;however, the high rate of repigmentation remains an unresolved global challenge. We conducted a self-controlled observational study of a patient with a nevus on the chest. Two areas of the lesion were treated with an Er:YAG laser and 5% imiquimod cream was applied to one of these areas. After nearly 7-months of follow-up, we observed a significant difference in color between the two areas, suggesting that topical imiquimod may inhibit repigmentation and significantly enhance the effectiveness of laser treatment.

Giant Cerebriform Nevus Cell Nevus of the Scalp: A Case Report

Giant cerebriform nevus cell nevus of the scalp is an extremely rare form of congenital melanocytic nevus. Giant cerebriform nevus of the scalp has a major psychosocial impact because of its unsightly appearance with fetid maceration. We report the case of a 35-year-old woman who had a painless, malodorous swelling of the cerebriform scalp measuring 20 × 17 cm in diameter with a wide base of insertion at the occipital level adhering to the deep planes. The excision associated with a skin plasty was carried out. Histology concluded that there was a giant cerebriform naevo-cellular nevus of the scalp.

History and prospect of melanocytic nevus treatment:A bibliometric analysis

Background:Melanocytic nevus is mainly treated by complete or partial removal.However,predicting the risk of malignant transformation of melanocytic nevi and which treatment patients should receive,surgical or nonsurgical management,to gain the best results and aesthetic outcomes is controversial.Methods:Global literature on melanocytic nevus treatment,published between 1997 and 2022,was scanned using the Web of Science Core Collection database.Microsoft Office Excel,CiteSpace V,VOSviewer,Scimago Graphica,Bibliometrix,and Biblioshiny packages in R were used for the bibliometric analysis to summarize the leading countries,institutions,professors,and research trends in this field.Results:This study included 1723 articles.Publications and citations exhibited positive trends over the past 20 years.The United States had the most productive organizations and publications in the comprehensive worldwide cooperation network,and China was recently one of the most active major participants.Professor Giovanni Pellacani,whose H-index,G-index,and M-index ranked first in this field,founded a virtual biopsy using reflectance confocal microscopy.In addition,Krengel and Kinsler contributed significantly to diagnosing and treating melanocytic nevi.The top 25 keywords in recent years were mostly about the mechanisms and risk factors for the malignant transformation of nevi.Conclusion:The future trend for melanocytic nevi treatment is to specify genotype-phenotype and genotypeoutcome correlations,choose proper therapy to reduce the risk of malignant transformation,and simultaneously achieve the best aesthetic outcomes.

Plantar Spitz Nevus Resembling Malignant Melanoma: Description of Immunohistochemical Findings

Spitz nevus (SN) is predominantly distributed throughout the lower extremities, while an acral location is rare. Since SN occasionally resembles the clinicopathological presentation of malignant melanoma (MM), it presents a diagnostic challenge, especially on glabrous skin. Past reports suggest that several genetic aberrations are associated with specific clinicopathological subtypes of melanocytic tumors. Immunohistochemistry can provide a clue to the presence or absence of a molecular aberration typical of Spitz tumors. We describe a case of a plantar SN with genetic analysis, including anaplastic lymphoma kinase (ALK), ROS proto-oncogene 1 (ROS1), BRAF (V600E) protein, and BRCA1-associated protein-1 (BAP1). However, we were not able to detect a characteristic gene aberration. To the best of our knowledge, no genetic aberrations in plantar SN cases have been reported. A comprehensive understanding of tumor genomics is expected to play an essential role in the classification of melanocytic tumors. Further genetic research on plantar SN is required to establish new criteria for distinguishing between SN and MM.

Dynamic MmWave Channel Reconstruction of MIMO OTA Testing for Handover Scenarios

The evaluation of handover performance is essential for ensuring seamless user experience under innovative application scenarios in the fifth generation(5G)and beyond era,including autonomous driving,mobile augmented and virtual reality.However,due to the hardware constrains of a sectored multiprobe anechoic chamber(SMPAC),switching among multiple channel models is of low precision with a high cost in traditional over-the-air(OTA)test solutions.In this paper,we present an efficient and repeatable emulation strategy to reconstruct dynamic millimeter-wave(mm Wave)channels in laboratories for multiple-input multiple-output(MIMO)mobile devices.Firstly,we propose a novel evaluation metric,called average power angular spectrum similarity percentage(APSP),which minimizes the unexpected impact induced by the indefinite condition of adaptive antenna arrays in mm Wave terminals during handover process.Moreover,we propose a partitioned probe configuration strategy by designing a beam directivitybased switching circuit,which enables quick changes of probe configurations in SMPAC.Simulation results demonstrate the effectiveness of the proposed algorithms,thus providing a guideline for the reconstruction of the dynamic channel in different scenarios with resource limitation.

Treatment of 522 patients with Nevus of Ota with Q switc hed Alexandrite laser

To evaluate the clinical response of Nevus of Ota to Q switched Alexandrite las er, and analyze factors that influence the treatment outcome Methods A total of 522 patients treated with Q switched Alexandrite laser were included in the study Single and multiple variate analyses of various factors were per formed Results Satisfactory result was observed in all patients, none of whom developed scarrin g Clinical response was improved with additional treatment sessions The clin ical response of the 20-27 week treatment interval group was significantly better t han that of the 12-19 week interval group, but showed no significant difference as compared with both the 28-35 and ≥36 week interval group Zygomatic, bucc al and frontal areas showed better response than ocular and temporal areas Tre atment session, interval, and fluence were significant factors identified by mul tivariate analysis Conclusions Q switched Alexandrite laser is an ideal method for treating Nevus of Ota witho ut injury The number of treatment sessions is more important than interval or fluence

Effect of Q-switched Alexandrite laser irradiation on epidermal melanocytes in treatment of Nevus of Ota

To investigate injury to epidermal melanocyte by Q-switched Alexandrite laser Methods Multiple biopsies were performed on 5 patients with nevus of Ota from before irradiation to 1 year after irradiation Fourteen specimens were obtained for light microscopy, and 17 for transmission electron microscopy Results Melanosomes in epidermal melanocytes were both smaller in size and fewer in number than those in dermal melanocytes Immediately after irradiation, focal extracellular vacuoles of the basal layer could be observed under light microscopy Most epidermal melanocytes underwent mild or moderate injury in the form of vacuolated melanosomes, swollen mitochondria, dilation of endoplasmic reticulum, and expansion of extracellular space, retaining intact cell membranes Normal structures were restored 5 months to 1 year after irradiation, with no depigmentation or hyperpigmentation as seen by light microscopy Conclusion Injury of melanosomes in epidermal melanocytes is reversible

A new classification of nevus of Ota

Background The nevus of Ota, is a common benign pigmentary dermatosis, mainly involve innervation area of first and second branch of trigeminal nerve. The classification of nevus of Ota was proposed by Tanino, based on 26 cases of nevus of Ota from 1937 to 1940. Studies about its classification are rarely seen in last 70 years, while it is still practical today.

是德科技携手泰尔终端实验室(CTTL)完成首个CTIA MIMO OTA动态信道模型测试系统验证

·此次合作成功验证5G NR FR1首个动态MIMO OTA信道模型·该解决方案可以对不同的终端设备制造商以及芯片组供应商的实际性能进行测试验证是德科技(Keysight Technologies,Inc.)日前宣布,该公司与泰尔终端实验室依据CTIA定义的5G NR FR1标准要求,共同构建了首个MIMO OTA动态信道模型测试和终端用户设备性能验证系统。

Response of nevus of Ota to Q-switched alexandrite laser according to treatment interval

In order to determine the appropriate treatment interval, 267 patients who underwent 3 sessions of treatment with Q-switched alexandrite laser were divided into 4 groups according to treatment interval, and their clinical responses were compared. Among them, 187 were asked about the process of pigment fading. Moreover, light and transmission electron microscopy were performed. It was noted that the clinical response of the 5 - 6 month interval group was significantly better than that of the 3 - 4 month group, but showed no significant difference from that of the 7 - 8 or ≥ 9 month group. 80.21% of investigated patients stated that marked pigment fading could no longer be observed 7 months after irradiation. 4 months after irradiation, the degenerated melanosomes and cell debris were still scattered among collagen fibers, scavenged gradually by macrophage. In conclusion, an appropriate treatment interval is 5 - 6 months.

A Novel Clock Feedthrough Frequency Compensation for Fast-Settling of Folded-Cascode OTA

Based on the minimum settling time （MST） theory and step-response analysis of the second order system in active switched capacitor （SC） networks, a novel clock feedthrough frequency compensation （CFFC） method for a folded-cascode OTA is proposed. The damping factor r/is adjusted by using MOS capacitors to introduce clock feedthrough so that the OTA can obtain the MST state and thus achieve fast settling. Research results indicate that the settling time of the compensated OTA is reduced by 22.7% ;as the capacitor load varies from 0.5 to 2.5pF,the improved settling time increases approximately linearly from 3.62 to 4.46ns： for VGA application, fast settling can also be achieved by modifying the MOS capacitor value accordingly when the closed loop gain of the compensated OTA varies.

A Linear CMOS OTA and Its Application to a 3.3V 20 MHz High-Q g_m-C Bandpass Filter

A design of a linear and fully-balanced operational transconductanee amplifier （OTA） with improved high DC gain and wide bandwidth is presented. Derivative from a single common-source field effect transistor （FET） cas- cade and its DC I-V characteristics,the third-order coefficient g3 hasbeen well compensated with a parallel FET operated in the triode region, which has even-odd symmetries between the boundary of the saturation and triode region. Therefore,for high linearity,a simple solution is obtained to increase input signal amplitude in saturation for the application of OTA continuous-time filters. A negative resistance load （NRL） technique is used for the compensation of parasitic output resistance and an achievement of a high DC-gain of the OTA circuits without extra internal nodes. Additionally, derivations from the ideal -90° phase of the gm-C integrator mainly due to a finite DC gain and parasitic poles will be avoided in the frequency range of interest. HSPICE simulation shows that the total harmonic distortion at 1Vp-p is less than 1% from a single 3.3V supply. As an application of the VHF CMOS OTA,a second-order OTA-C bandpass filter is fabricated using a 0. 18μm CMOS process with two kinds of gate-oxide layers, which has achieved a center frequency of 20MHz,a 3dB-bandwidth of 180kHz,and a quality factor of 110.

Effect of Q-switched alexandrite laser irradiation on dermal melanocytes of nevus of Ota

OBJECTIVE: To investigate the effect of Q-switched alexandrite laser irradiation on dermal melanocytes of nevus of Ota. METHODS: Multiple biopsies were carried out on 4 patients with nevus of Ota before and after laser irradiation. Altogether 11 samples were examined under light microscope and 14 under transmission electron microscope. RESULTS: Immediately after laser irradiation, the dermal melanocytes were destroyed, the melanosomes were degenerated with central vesicle formation within most of them, and intradermal round vacuoles appeared. The epidermis remained intact. Three months to 1 year after irradiation, the degenerated melanosomes and cell debris were scavenged mainly by macrophages. Dermal melanocytes gradually decreased. No fibrosis was found. CONCLUSION: Q-switched alexandrite laser can selectively destroy dermal melanocytes of nevus of Ota and treat the disease safely.

Blue rubber bleb nevus syndrome:A case report and literature review

Blue rubber bleb nevus syndrome(BRBNS)is a rare disease characterized by multiple venous malformations and hemangiomas in the skin and visceral organs.The lesions often involve the cutaneous and gastrointestinal systems.Other organs can also be involved,such as the central nervous system,liver,and muscles.The most common symptoms are gastrointestinal bleeding and secondary iron deficiency anemia.The syndrome may also present with severe complications such as rupture,intestinal torsion,and intussusception,and can even cause death.Cutaneous malformations are usually asymptomatic and do not require treatment.The treatment of gastrointestinal lesions is determined by the extent of intestinal involvement and severity of the disease.Most patients respond to supportive therapy,such as iron supplementation and blood transfusion.For more significant hemorrhages or severe complications,surgical resection,endoscopic sclerosis,and laser photocoagulation have been proposed.Here we present a case of BRBNS in a 45-year-old woman involving 16sites including the scalp,eyelid,orbit,lip,tongue,face,back,upper and lower limbs,buttocks,root of neck,clavicle area,superior mediastinum,glottis,esophagus,colon,and anus,with secondary severe anemia.In addition,we summarize the epidemiology,clinical manifestations,diagnosis,differential diagnosis and therapies of this disease by analyzing all previously reported cases to enhance the awareness of this syndrome.

Radiofrequency ablation micro-dissecting of eyelid nevus with XL-RFA device under operating microscope

AIM: To study the effect of an innovative micro-dissection procedure by radiofrequency ablation (MRA) in removing eyelid nevus.METHODS: Fifty-six consecutive outpatients with eyelid nevus were treated with MRA using a monopolar device. The effect of MRA was determined after following-up for 6mo to 5y.RESULTS: Fifty-two cases (52 eyes, 92.9%) were cured once, and 4 cases (4 eyes, 7.1%) received second treatment for small residual. All cases healed well after surgery, with no pigmentation, no scars, no loss of eyelashes, no deformation of eyelid margin. There was no visual impairment after healing.CONCLUSION: MRA of eyelid nevus using the XL-RFA device is highly efficient without significant complications.

Endoscopic therapy for esophageal hematoma with blue rubber bleb nevus syndrome

A 57-year-old woman previously diagnosed with blue rubber bleb nevus syndrome(BRBNS) reported hematemesis. BRBNS is a rare vascular anomaly syndrome consisting of multifocal hemangiomas of the skin and gastrointestinal(GI) tract but her GI tract had never been examined. An upper gastrointestinal endoscopy revealed a large bleeding esophageal hematoma positioned between the thoracic esophagus and the gastric cardia. An endoscopic injection of polidocanol was used to stop the hematoma from bleeding. The hematoma was incised using the injectionneedle to reduce the pressure within it. Finally, argon plasma coagulation(APC) was applied to the edge of the incision. The esophageal hematoma disappeared seven days later. Two months after the endoscopic the rapy, the eso phage alulcerhealed and the hemangioma did not relapse. This rare case of a large esophageal hematoma originating from a hemangioma with BRBNS was treated using a combination of endoscopic therapy with polidocanol injection, incision, and APC.

Effects of Q-Switched Laser Treatments on Acquired Bilateral Nevus of Ota-Like Macules: A Retrospective Comparative Study

Objective:Q-switched lasers,including 1064-nm Nd:YAG nansecond laser (QSNYL),755-nm alexandrite nanosecond laser (QSAL),and 694-nm nanosecond ruby laser (QSRL),are clinically available for the treatment of acquired bilateral nevus of Ota-like macules (ABNOM).However,no reliable evidence from large-scale comparative studies identifies which type of laser works best.This study aims to determine the differences in the effectiveness,complications,and risk factors of QSNYL,QSAL,and QSRL in the treatment of ABNOM,further to provide evidence for clinician to make optimal choice according to the condition of patients.Methods:We collected the data from 685 ABNOM patients,including clinical features,medical treatments,and follow-up,since 1999 to 2014.The Kruskal-Wallis test was used to compare therapeutic differences between the three groups.The risk factors were analyzed using univariate analysis (x2 test) and multivariate logistic regression analysis.Results:The overall treatment efficiency of the QSNYL group (52.5%) and QSAL group (51.9%) was higher than that of the QSRL group (39.5%) (x2 =17.468,P < 0.001).The onset time of the QSRL and QSAL groups was shorter than that of the QSNYL group.The factors influencing efficacy in the QSNYL group were age at first treatment,number of treatments,coexistence with melesma,and the presence of hyperpigmentation;in the QSAL group was the number of treatments;and in the QSRL group was the number of treatments and hyperpigmentation.The prevalence of hyperpigrnentation in the QSNYL group (30.5%) and the QSAL group (27.5%) was lower than that of the QSRL group (47.3%) (X2=6.576,P<0.001).Concluslon:The QSNYL,QSAL,and QSRL are all effective and safe treatments for ABNOM.Considering the overall efficacy,duration of treatment,side effects,and risk factors,the QSAL is an optimal choice for ABNOM treatment.

一种基于衬底驱动技术的0.8V高性能CMOS OTA

基于衬底驱动MOS技术。设计了一种0．8V COMS跨导运算放大器（OTA），在互补输入差分对的衬底端施加信号避开MOSFET阈值电压的限制以达到超低压应用,通过额外的共源放大器来提高OTA的增益。在±0．4v的电源电压下，其直流开环增益为73．8dB，单位增益带宽为16．4MHz，相位裕度为53°，功耗为125．4μW，输出电压范围为-0．337～0．370V。