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1.
Rev Sci Instrum ; 94(5)2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37204283

RESUMO

We have developed a new scintillator-based optical soft x-ray (OSXR) diagnostic system for KSTAR. By utilizing fiber optic faceplates, mm-size lens arrays, and fiber bundles, we have successfully constructed a novel optical system for scintillator-based soft x-ray detection to overcome the limited vacuum-port conditions in KSTAR. P47 (Y2SiO5), which has a fast rise (∼7 ns) and decay (∼100 ns) time sufficient for detecting plasma instabilities observed in the kHz-MHz spectral range, was selected as the scintillator material for the KSTAR OSXR system. Scintillation toward each detection channel is collected by the lens arrays coupled to optical fiber cores, which are connected to the photodetector system. Initial results obtained during the 2022 KSTAR experimental campaign support the validity of the OSXR data through the consistency of OSXR measurement results with other diagnostics. We also observe that the OSXR system can capture magnetohydrodynamic activities, such as sawtooth oscillations, and provide valuable information for disruption mitigation studies using shattered pellet injection.

2.
Rev Sci Instrum ; 93(9): 093506, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36182494

RESUMO

A new soft x-ray (SXR) array diagnostic system has been developed on versatile experiment spherical torus (VEST) for measurements of 2D SXR emissivity profile and identification of poloidal mode structure. Through tomographic inversion techniques, 2D SXR emissivity profile can be acquired from the line-integrated SXR data, which enables the visualization of mode structure of plasma instability, such as the magnetohydrodynamics mode. The SXR array diagnostic system consists of two 20-channel arrays positioned at the middle and the top on the same poloidal plane for horizontal and vertical lines of sight, respectively. Each array of the diagnostic system uses absolute extreme ultraviolet photodiode array as the detector. To apply appropriate filters (up to four) for different energy regimes without breaking the vacuum, a filter wheel and its rotatable vacuum feed-through are installed behind the pinhole. SXR data are acquired with a digitizer at the sampling rate of up to 125 MHz. Finally, we discuss initial measurement data obtained from Ohmic plasma in VEST.

3.
Org Lett ; 22(18): 7387-7392, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32903016

RESUMO

Transition-metal-catalyzed transformations of the carbon-fluorine bond not only tackle an interesting problem of challenging bond activation but also offer new synthetic strategies where the relatively inert C-F bond is converted to versatile functional groups. Herein we report a practical cobalt-catalyzed silylation of aryl fluorides that uses a cheap electrophilic silicon source with magnesium. This method is compatible with various silicon sources and can be operated under aerobic conditions. Mechanistic studies support the in situ formation of a Grignard reagent, which is captured by the electrophilic silicon source.

4.
Plast Reconstr Surg Glob Open ; 8(7): e2964, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32802658

RESUMO

Resection of large mandibular tumors followed by primary reconstruction using free tissue transfer is typically accomplished using transcutaneous cervical incisions, which provide access for ablation as well as inset of the osseous free flap. This approach offers wide exposure; however, it subjects the patient to potential facial scarring, marginal mandibular nerve injury, lip deformity/incompetence, formation of orocutaneous fistulae, as well as functional impairments to speech, mastication, and deglutition. To reduce morbidity and to preserve aesthetics, a transoral approach can be used in cases that do not require a neck dissection. This technique can be coupled with transoral dissection of the facial vessels for intraoral microanastomoses to avoid extraoral incisions altogether. We present a case of a large 17.2 cm subtotal mandibulectomy and 3-segment fibular free flap reconstruction using virtual surgical planning, with patient-specific cutting guides and reconstruction plate performed entirely transorally without any skin incisions. Although technically challenging, this is a safe and effective technique for large segmental mandibular defects, which provides superior cosmetic and functional outcomes.

5.
Ann Plast Surg ; 84(6S Suppl 5): S424-S430, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32032110

RESUMO

BACKGROUND: Precise flap planning and perforator selection are paramount for successful perforator flap surgery. Portable color-flow ultrasound (PCFU) is a convenient, low-cost, easily accessible imaging modality that is pivotal in the planning of perforator flaps where anatomic variability is the rule. METHODS: Perforator mapping was performed using an L12-4 linear-array ultrasound probe connected to an Android tablet. Images were obtained with the Lumify app (Philips Lumify, usa.philips.com). Perforator characteristics were recorded (arterial diameter, emergence points from fascia, subcutaneous course, and projection onto the skin surface) using still images and real-time videos. RESULTS: Thirty consecutive patients had 40 perforator or musculocutaneous flap reconstructions over a 2-year period. For the 15 flaps that had preoperative computed tomographic angiography (CTA) imaging, the preoperative sonographic measurements correlated with CTA and intraoperative findings. Portable color-flow ultrasound allowed perforator flap design and selection based on the largest available perforator, the most appropriate flap thickness, and comparison of multiple donor sites including left versus right. Two deep inferior epigastric perforator patients required take-back to the operating room for debridement of devitalized nonflap tissue. The superior gluteal artery perforator flap was abandoned intraoperatively due to proximal vascular anomalies. Overall flap success rate was 98% (39/40 flaps). CONCLUSIONS: Our experience with PCFU has rapidly improved, allowing individualized perforator flap selection and design based on each patient's unique perforator anatomy, reconstructive requirements, and donor site characteristics. In our practice, PCFU has supplemented CTA and in many cases has supplanted CTA as the primary imaging modality of choice in the planning of perforator flap reconstruction.


Assuntos
Mamoplastia , Retalho Perfurante , Procedimentos de Cirurgia Plástica , Cirurgia Plástica , Angiografia , Humanos , Microcirurgia , Retalho Perfurante/cirurgia
6.
Rev Sci Instrum ; 89(10): 10I118, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399758

RESUMO

In time-resolved measurement for triton burnup in Korea Superconducting Tokamak Advanced Research (KSTAR) deuterium plasmas, an NE213 liquid scintillation detector was installed and operated during the 2017 KSTAR campaign. The detector is composed of an NE213 scintillator (50 mm in diameter and 10 mm in thickness) and a photomultiplier tube (PMT). The PMT anode signal was processed under a data acquisition system which contains a field programmable gate array circuit and pulse processing software that is capable of discriminating gamma-ray and neutron pulse signals. In order to determine an appropriate threshold level for the 14 MeV neutron signal resulting from triton burnup, the NE213 scintillation detector was calibrated by using d-d and d-t neutron generators at the National Fusion Research Institute and Intense 14 MeV Neutron Source Facility, OKTAVIAN, Osaka University, Japan. The detector was installed on KSTAR with a 10 mm thick soft-iron stray magnetic field shield and a radiation shield which consists of 100 mm thick lead blocks and 200 mm thick borated polyethylene blocks. A discrimination range for d-t neutron was determined based on test results from neutron generators and KSTAR. Data points selected from the discrimination range were consistent with the classical triton confinement characteristics. In conclusion, under condition of an input counting rate of 1.9 × 105 counts per second (CPS), the detector is able to measure triton burnup signals up to 500 CPS for various plasma parameters.

7.
Org Lett ; 20(22): 7249-7252, 2018 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-30388011

RESUMO

A mild and practical cobalt-catalyzed defluoroborylation of fluoroarenes is presented for the first time. The method permits straightforward functionalization of fluoroarenes, with high selectivity for borylation of C-F over C-H bonds, and a tolerance for aerobic conditions. Furthermore, two-step 18F-fluorination was achieved for expanding the scope of 18F-positron emission tomography probes.

8.
Ann Plast Surg ; 81(4): 503-507, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30204622

RESUMO

PURPOSE: Phentermine is the most prescribed antiobesity drug in America, with 2.43 million prescriptions written in 2011. Case reports suggest there are anesthetic risks, such as refractory hypotension, involved with its perioperative use. Despite these risks and the frequency of phentermine use among plastic surgery patients, there are no published guidelines for the perioperative management of phentermine use in the plastic surgery literature. To address this patient safety issue, we performed a systematic review and provide management recommendations. METHODS: A systematic review of the pharmacology of phentermine and the anesthetic risks involved with its perioperative use was undertaken using the search engines PubMed/MEDLINE, EMBASE, and Scopus. RESULTS: A total of 251 citations were reviewed, yielding 4 articles that discussed perioperative phentermine use and complications with anesthesia. One was a review article, 2 were case reports, and 1 was a letter. Complications included hypotension, hypertension, hypoglycemia, hyperthermia, bradycardia, cardiac depression, and acute pulmonary edema. CONCLUSIONS: The relationship between phentermine and anesthesia, if any, is unclear. Hypotension on induction of general anesthesia is the most reported complication of perioperative phentermine use. Specifically, phentermine-induced hypotension may be unresponsive to vasopressors that rely on catecholamine release, such as ephedrine. Therefore, the decision to perform surgery, especially elective surgery, in a patient taking phentermine should be made with caution. Because of the half-life of phentermine, we recommend discontinuing phentermine for at least 4 days prior to surgery. This differs from the classic 2-week discontinuation period recommended for "fen-phen." The patient should be made aware of the increased risk of surgery, and a skilled anesthesiologist should monitor intraoperative blood pressure and body temperature for signs of autonomic derailment.


Assuntos
Anestesia , Anestésicos/farmacologia , Depressores do Apetite/farmacologia , Fentermina/farmacologia , Procedimentos de Cirurgia Plástica , Anestésicos/efeitos adversos , Depressores do Apetite/efeitos adversos , Interações Medicamentosas , Humanos , Fentermina/efeitos adversos
9.
Ann Plast Surg ; 80(6S Suppl 6): S356-S361, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29668508

RESUMO

BACKGROUND: Color Doppler ultrasound (CDUS) has not been routinely used in plastic and reconstructive surgery. Barriers to use have included large, cumbersome equipment, low-definition images, cost, and availability. In addition, programs in plastic surgery have not included training with ultrasound (US); thus, many current-day practitioners are unfamiliar with and reluctant to use this technology. Nevertheless, recent studies have demonstrated the utility of US in surgical planning. With the miniaturization, clearer imaging, and decreased costs of the latest US technology, previous barriers to use have largely been eliminated. METHODS: Fifty-six patients scheduled for either reconstructive or aesthetic surgery were evaluated preoperatively and/or intraoperatively by a single surgeon with the linear 12-4 probe of a Philips Lumify CDUS device (Philips, Reedsville, Penn). For patients undergoing flap reconstruction, potential donor sites were imaged in order to locate the largest perforator. For patients undergoing abdominal procedures, intraoperative visualization of the abdominal muscular layers was used for the delivery of anesthesia during transversus abdominis plane block. Lastly, the superficial fascial system (SFS) was subjectively evaluated in all preoperative patients. RESULTS: For flap reconstruction, 11 patients were preoperatively examined with CDUS in order to locate the largest perforators prior to perforator flap reconstruction. Flaps studied included the deep inferior epigastric perforator, anterolateral thigh, tensor fascia lata, thoracodorsal artery perforator, superior gluteal artery perforator, and the gracilis musculocutaneous. Color Doppler ultrasound findings were confirmed intraoperatively for all cases (100%). In 2 (18.2%) of 11 cases, CDUS identified perforators not detected by computed tomography angiography. Twenty-five patients undergoing either abdominoplasty or deep inferior epigastric perforator flap reconstruction had successful intraoperative visualization of the abdominal wall muscular layers, thus allowing administration of transversus abdominis plane blocks by the operating surgeon. Twenty patients undergoing body contouring surgery had preoperative visualization of the SFS. The SFS was found to be varied not only among different patients but also within individual patients. CONCLUSIONS: The newest, miniaturized CDUS technology has a variety of applications that may improve patient outcomes and experience in plastic surgery. Our observations require further investigation to quantify the perceived benefits of this new technology.


Assuntos
Músculos Abdominais/diagnóstico por imagem , Técnicas Cosméticas , Cuidados Intraoperatórios/instrumentação , Procedimentos de Cirurgia Plástica , Cuidados Pré-Operatórios/instrumentação , Retalhos Cirúrgicos/irrigação sanguínea , Ultrassonografia Doppler em Cores/instrumentação , Adulto , Idoso , Idoso de 80 Anos ou mais , Fáscia/diagnóstico por imagem , Feminino , Humanos , Cuidados Intraoperatórios/métodos , Masculino , Pessoa de Meia-Idade , Bloqueio Nervoso/métodos , Cuidados Pré-Operatórios/métodos , Ultrassonografia Doppler em Cores/métodos
10.
J Reconstr Microsurg ; 34(4): 300-306, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28987081

RESUMO

BACKGROUND: Variations in anterolateral thigh (ALT) arterial anatomy are well documented. Ethnicity is a known risk factor for vascular variation in several organ systems, but its impact on ALT anatomy has not been studied. Anecdotally, we observed frequent ALT arterial variation in African American (AA) patients. We thus hypothesized that AA patients have higher rates of anomalous branching. MATERIALS AND METHODS: A total of 277 computed tomography angiograms (513 lower extremities) captured between May 1, 2013 and May 31, 2015 at a tertiary academic medical center were retrospectively analyzed to determine ALT arterial branching. Patient records were examined to ascertain demographics. Data were analyzed using descriptive statistics and multinomial logistic regression. RESULTS: Males comprised 84.5%. Ethnic distribution was 55.2% AA and 36.5% Caucasian. The descending branch of the lateral circumflex femoral artery (dLCFA) originated from non-LCFA arteries (deep femoral, common femoral, or superficial femoral arteries) in 18.9% of Caucasian versus 9.1% of AA (odds ratio [OR]: 2.28; 95% confidence interval [CI]: 1.33-3.93, p < 0.01). An oblique branch was identified in 41.1% of Caucasian versus 51.9% of AA (OR: 1.56; 95% CI: 1.08-2.24, p = 0.02). Ethnicity was the only driving factor of dLCFA and oblique branch of the LCFA (oLCFA) anatomy (Wald chi-square: 14 and 11, p = 0.03 and 0.02, respectively). CONCLUSIONS: Ethnicity significantly affects ALT arterial anatomy. AA are more likely to have classical dLCFA branching with a fourth oLCFA branch. A flap with an unrecognized oLCFA-dominant supply places patients at a higher risk for flap failure and loss. We recommend preoperative imaging before undertaking an ALT flap reconstruction.


Assuntos
Negro ou Afro-Americano , Angiografia por Tomografia Computadorizada , Artéria Femoral/anatomia & histologia , Procedimentos de Cirurgia Plástica/educação , Coxa da Perna/irrigação sanguínea , Adulto , Análise de Variância , Estudos Transversais , Etnicidade , Feminino , Artéria Femoral/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Coxa da Perna/anatomia & histologia , Coxa da Perna/diagnóstico por imagem , População Branca
11.
Aesthetic Plast Surg ; 41(1): 171-178, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28032173

RESUMO

BACKGROUND: Fractional lasers were introduced to provide increased safety, while maintaining high efficacy and patient satisfaction. Patients with virtually all Fitzpatrick skin types could be safely treated using a wide spectrum of wavelengths and a broad array of skin conditions, and aging could be addressed. Although safety studies have been reported for ablative CO2 and erbium lasers, surprisingly few data are available on adverse events and complications associated with fractional lasers. OBJECTIVE: We report the frequency of adverse events, skin improvement and complications in a broad range of skin types using a standardized protocol that can be safely tailored to the patient's presenting complaints by varying the laser wavelength and number of treatments. MATERIALS AND METHODS: The medical records of 730 patients (>90% females, age ranged from 50.5. to 59.9 years.) who had been treated at FACES+ Aesthetic Facility were reviewed. Patients were followed from 1 to 10 months and were reviewed to determine the frequency of complications, as well as their frequency, type, cause, treatment and resolution thereof. Patients were categorized by Fitzpatrick skin type (I-IV) to determine whether skin type was related to the frequency of complications. Improvement in skin condition (wrinkles, nasolabial folds and pigment) was rated by a technician before and after treatment using a Likert scale, 0-5, with 0 being no change and 5 being the most improvement. RESULTS: Seven hundred thirty patients underwent procedures using fractional lasers in our center. Procedures were carried out with 3 different laser wavelengths, depending on the condition(s) treated (wrinkling vs. pigmentation issues, etc.) and the patients' desired length of downtime. The fractional Fraxel 1927-nm laser was used in 224 patients [Fitzpatrick skin type I (2.2%), II (38.4%), III (46.0%), IV (12.5%)]; the fractional Fraxel 1550-nm laser was used in 334 [type I (4.5%), II (31.9%), III (50.0%), IV (13.3%)], and the fractional Fraxel CO2 laser was used in 172 [type 1 (4.7%), II (49.7%), III (41.5%), IV (4.1%)]. The Fraxel CO2 laser showed greater improvement in wrinkles and naso-labial fold (p < 0.001). The greatest improvement in pigmentation was seen with the Fraxel 1927-nm laser (p < 0.001). Adverse events and complications occurred in 31 of 730 patients (4.2%). There was no significant difference in the rate of complications among the three treatments (p = 0.26). Complications were generally minor, and all resolved completely with treatment. Complications occurred in 4.0% of patients having the fractional Fraxel 1927-nm laser, 3.3% of patients having the fractional Fraxel 1550 nm and 6.4% of patients having the fractional Fraxel CO2 laser. Complications included 5 herpes simplex virus breakouts, 13 acne eruptions, 1 abrasion, 1 bacterial infection, 9 dermatitis, 1 drug eruption, 4 prolonged erythema, 1 hyperpigmentation, 1 increased swelling and 1 telangiectasia. There was no significant relationship between Fitzpatrick skin type and incidence of complications (p = 0.37). CONCLUSIONS: Fractional lasers in general have reduced complication rates, while maintaining high degrees of patient satisfaction. Since their inception in early 2004, our clinic has utilized fractional lasers to treat patients from a variety of ethnic backgrounds and diverse skin types with an overall complication rate of 4.2%, all of which resolved. Comprehensive care of patients with facial aging is not limited to surgery alone and should include these types of strategies to appropriately and safely address photo-damage and photo-aging. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Lasers de Gás , Lasers de Estado Sólido , Terapia com Luz de Baixa Intensidade/efeitos adversos , Terapia com Luz de Baixa Intensidade/métodos , Satisfação do Paciente/estatística & dados numéricos , Técnicas Cosméticas , Bases de Dados Factuais , Edema/etiologia , Edema/fisiopatologia , Eritema/etiologia , Eritema/fisiopatologia , Estética , Feminino , Humanos , Hiperpigmentação/diagnóstico , Hiperpigmentação/radioterapia , Masculino , Seleção de Pacientes , Estudos Retrospectivos , Medição de Risco , Envelhecimento da Pele , Resultado do Tratamento
12.
Plast Reconstr Surg Glob Open ; 4(2): e610, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27014539

RESUMO

This case report discusses the reconstruction of an entire thumb metacarpal after a diagnosis of giant cell tumor of bone. The patient underwent excision of the entire thumb metacarpal, followed by interposition of a tricortical iliac crest bone graft and metacarpophalangeal and carpometacarpal joint arthrodeses. This option allowed salvage of the patient's native thumb with functional use as a stable post to which she can pinch and grasp objects. At 9 months postoperatively, there was no evidence of recurrence.

13.
PLoS One ; 7(9): e44223, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22984479

RESUMO

BACKGROUND: A plethora of biological metabolisms are regulated by the mechanisms of ubiquitination, wherein this process is balanced with the action of deubiquitination system. Dub-2 is an IL-2-inducible, immediate-early gene that encodes a deubiquitinating enzyme with growth regulatory activity. DUB-2 presumably removes ubiquitin from ubiquitin-conjugated target proteins regulating ubiquitin-mediated proteolysis, but its specific target proteins are unknown yet. METHODOLOGY/PRINCIPAL FINDINGS: To elucidate the functional role of Dub-2, we generated genetically modified mice by introducing neo cassette into the second exon of Dub-2 and then homologous recombination was done to completely abrogate the activity of DUB-2 proteins. We generated Dub-2+/- heterozygous mice showing a normal phenotype and are fertile, whereas new born mouse of Dub-2-/- homozygous alleles could not survive. In addition, Dub-2-/- embryo could not be seen between E6.5 and E12.5 stages. Furthermore, the number of embryos showing normal embryonic development for further stages is decreased in heterozygotes. Even embryonic stem cells from inner cell mass of Dub-2-/- embryos could not be established. CONCLUSIONS: Our study suggests that the targeted disruption of Dub-2 may cause embryonic lethality during early gestation, possibly due to the failure of cell proliferation during hatching process.


Assuntos
Perda do Embrião/enzimologia , Perda do Embrião/patologia , Endopeptidases/genética , Deleção de Genes , Marcação de Genes , Proteínas Imediatamente Precoces/genética , Animais , Apoptose , Massa Celular Interna do Blastocisto/metabolismo , Massa Celular Interna do Blastocisto/patologia , Proliferação de Células , Sobrevivência Celular , Desenvolvimento Embrionário , Endopeptidases/deficiência , Endopeptidases/metabolismo , Fertilização in vitro , Técnicas de Genotipagem , Heterozigoto , Proteínas Imediatamente Precoces/deficiência , Proteínas Imediatamente Precoces/metabolismo , Tecido Linfoide/metabolismo , Tecido Linfoide/patologia , Masculino , Camundongos , Camundongos Mutantes , Fenótipo , Motilidade dos Espermatozoides , Espermatozoides/patologia , Baço/patologia , Timo/patologia
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