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1.
J Urol ; 207(5): 1105-1115, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34968146

RESUMO

PURPOSE: We sought to automate R.E.N.A.L. (for radius, exophytic/endophytic, nearness of tumor to collecting system, anterior/posterior, location relative to polar line) nephrometry scoring of preoperative computerized tomography scans and create an artificial intelligence-generated score (AI-score). Subsequently, we aimed to evaluate its ability to predict meaningful oncologic and perioperative outcomes as compared to expert human-generated nephrometry scores (H-scores). MATERIALS AND METHODS: A total of 300 patients with preoperative computerized tomography were identified from a cohort of 544 consecutive patients undergoing surgical extirpation for suspected renal cancer at a single institution. A deep neural network approach was used to automatically segment kidneys and tumors, and geometric algorithms were developed to estimate components of R.E.N.A.L. nephrometry score. Tumors were independently scored by medical personnel blinded to AI-scores. AI- and H-score agreement was assessed using Lin's concordance correlation and their predictive abilities for both oncologic and perioperative outcomes were assessed using areas under the curve. RESULTS: Median age was 60 years (IQE 51-68), and 40% were female. Median tumor size was 4.2 cm and 91.3% had malignant tumors, including 27%, 37% and 24% with high stage, grade and necrosis, respectively. There was significant agreement between H-scores and AI-scores (Lin's ⍴=0.59). Both AI- and H-scores similarly predicted meaningful oncologic outcomes (p <0.001) including presence of malignancy, necrosis, and high-grade and -stage disease (p <0.003). They also predicted surgical approach (p <0.004) and specific perioperative outcomes (p <0.05). CONCLUSIONS: Fully automated AI-generated R.E.N.A.L. scores are comparable to human-generated R.E.N.A.L. scores and predict a wide variety of meaningful patient-centered outcomes. This unambiguous artificial intelligence-based scoring is intended to facilitate wider adoption of the R.E.N.A.L. score.


Assuntos
Inteligência Artificial , Neoplasias Renais , Computadores , Feminino , Humanos , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Pessoa de Meia-Idade , Necrose , Nefrectomia/métodos , Estudos Retrospectivos
2.
Phys Chem Chem Phys ; 24(44): 27121-27127, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36342321

RESUMO

During the last decade, X-ray free-electron lasers (XFELs) have enabled the study of light-matter interaction under extreme conditions. Atoms which are subject to XFEL radiation are charged by a complex interplay of (several subsequent) photoionization events and electronic decay processes within a few femtoseconds. The interaction with molecules is even more intriguing, since intricate nuclear dynamics occur as the molecules start to dissociate during the charge-up process. Here, we demonstrate that by analyzing photoelectron angular emission distributions and kinetic energy release of charge states of ionic molecular fragments, we can obtain a detailed understanding of the charge-up and fragmentation dynamics. Our novel approach allows for gathering such information without the need of complex ab initio modeling. As an example, we provide a detailed view on the processes happening on a femtosecond time scale in oxygen molecules exposed to intense XFEL pulses.

3.
Phys Rev Lett ; 126(8): 083201, 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33709766

RESUMO

We investigate the differential ionization probability of chiral molecules in the strong-field regime as a function of the helicity of the incident light. To this end, we analyze the fourfold ionization of bromochlorofluoromethane (CHBrClF) with subsequent fragmentation into four charged fragments and different dissociation channels of the singly ionized methyloxirane. By resolving for the molecular orientation, we show that the photoion circular dichroism signal strength is increased by 2 orders of magnitude.

4.
Phys Rev Lett ; 127(10): 103201, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34533326

RESUMO

We report on a joint experimental and theoretical study of photoelectron circular dichroism (PECD) in methyloxirane. By detecting O 1s photoelectrons in coincidence with fragment ions, we deduce the molecule's orientation and photoelectron emission direction in the laboratory frame. Thereby, we retrieve a fourfold differential PECD clearly beyond 50%. This strong chiral asymmetry is reproduced by ab initio electronic structure calculations. Providing such a pronounced contrast makes PECD of fixed-in-space chiral molecules an even more sensitive tool for chiral recognition in the gas phase.

5.
Support Care Cancer ; 28(10): 4667-4675, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31955277

RESUMO

PURPOSE: Patients with advanced cancer often receive suboptimal end-of-life (EOL) care. Particularly males with advanced cancer are more likely to receive EOL care that is more aggressive, even if death is imminent. Critical factors determining EOL care are EOL conversations or advance care planning. However, information about gender-related factors influencing EOL conversations is lacking. Therefore, the current study investigates gender differences concerning the content, the desired time point, and the mode of initiation of EOL conversations in cancer patients. METHODS: In a cross-sectional study, 186 female and male cancer patients were asked about their preferences for EOL discussions using a semi-structured interview, focusing on (a) the importance of six different topics (medical and nursing care, organizational, emotional, social, and spiritual/religious aspects), (b) the desired time point, and (c) the mode of discussion initiation. RESULTS: The importance of EOL topics differs significantly regarding issue (p = 0.002, η2 = 0.02) and gender (p < 0.001, η2 = 0.11). Males wish to avoid the engagement in discussions about death and dying particularly if they are anxious about their end-of-life period. They wish to be addressed regarding the "hard facts" nursing and medical care only. In contrast, females prefer to speak more about "soft facts" and to be addressed about each EOL topic. Independent of gender, the majority of patients prefer to talk rather late: when the disease is getting worse (58%), at the end of their therapy, or when loosing self-sufficiency (27.5%). CONCLUSION: The tendency of patients to talk late about EOL issues increases the risk of delayed or missed EOL conversations, which may be due to a knowledge gap regarding the possibility of disease-associated incapability. Furthermore, there are significant gender differences influencing the access to EOL conversations. Therefore, for daily clinical routine, we suggest an early two-step, gender-sensitive approach to end-of-life conversations.


Assuntos
Planejamento Antecipado de Cuidados/normas , Neoplasias/psicologia , Assistência Terminal/psicologia , Estudos Transversais , Feminino , Identidade de Gênero , Humanos , Masculino
6.
J Cosmet Laser Ther ; 21(2): 71-75, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29764244

RESUMO

INTRODUCTION: Fractionated radiofrequency (RF) tissue tightening is an alternative method to fractionated laser treatment of skin wrinkling, laxity and acne scars, with reduced risk of scarring or persistent pigmentation. The aim of this study was to evaluate and quantify the wound healing process after RF treatment. MATERIALS AND METHODS: 12 patients were treated with a 64-pin fractional bipolar RF device with 60 mJ/pin applied energy. Confocal laser scanning microscopy (CLSM) examination was performed on day 1, day 2, day 7 and day 14 after treatment. Clinical wound healing process was measured and expressed as a percentage. RESULTS: All patients developed erythema, mild edema and crusts at the treated areas. Two weeks after treatment clinical symptoms resolved. During ablation patients reported moderate pain. Directly after ablation microscopic ablation zones could be detected in CLSM. Measurement of MAZ at epidermis, dermo-epidermal junction and papilary dermis showed a constant diameter until two weeks after treatment. Re-epithelization of the MAZ could be detected already 1 week after treatment. However, 2 weeks after ablation the honeycomb pattern of the epidermis was not yet completely restored. DISCUSSION: Bipolar fractionated RF treatment demonstrates clinically a rapid wound healing response. The subepidermal remodelling process still ongoing after 14 days, showing new granulation tissue. Therefore, treatment intervals of at least 14 days should be recommended to allow completion of the remodelling process.


Assuntos
Terapia por Radiofrequência , Envelhecimento da Pele/efeitos da radiação , Cicatrização/efeitos da radiação , Adulto , Técnicas Cosméticas/efeitos adversos , Eritema/etiologia , Feminino , Humanos , Masculino , Microscopia Confocal , Dor/etiologia , Ondas de Rádio/efeitos adversos , Cicatrização/fisiologia
7.
Int J Cosmet Sci ; 41(5): 472-478, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31339574

RESUMO

OBJECTIVE: To confirm the robustness and validity of an automatic scoring system, algorithm-based, that grades the severity of nine facial signs through "selfies" smartphones pictures taken by European Caucasian women through dermatological assessments. METHODS: 157 Caucasian women from three countries (France, Germany, Spain), of different ages (20-75 years), took one "selfie" image by the frontal camera of their smartphones whereas local dermatologists photographed them with the back camera of the same smartphone. The same nine facial signs of these subjects were initially graded by these local dermatologists, using referential Skin Aging Atlases. All 314 "selfies" images were then further automatically analyzed by the algorithm. The severity of facial signs (wrinkles, pigmentation, ptosis, skin folds etc.) were statistically compared to the assessments made by the three dermatologists, taken as ground truth. RESULTS: Highly significant coefficients of correlation (P < 0.001) were found in the three cohorts between the grades provided by the system and those from dermatologists in live. The back camera - of a better resolution than the frontal one - seems affording slightly more significant correlations. However, although significantly correlated, the signs of vascular disorders and cheek skin pores present some disparities that are likely linked to the technical diversity of smartphones or self-shootings, leading to lower coefficients of correlations. CONCLUSION: This automatic scoring system offers a promising approach in the harmonization of Dermatological assessments of skin facial signs and their changes with age or the follow up of anti-aging treatments.


OBJECTIF: De confirmer la validité et la solidité d'un système de scorage automatique qui quantifie la sévérité de neuf signes du visage à partir de photographies de type "selfies" prises par des femmes Caucasiennes Européennes d'âge différents. MÉTHODES: 157 femmes Caucasiennes de trois pays différents (France, Allemagne, Espagne), d'âges différents (20-75 ans) ont pris un « selfie¼ avec la caméra frontale de leur téléphone tandis que le dermatologue local les a photographiées à l'aide de la caméra dorsale du même appareil. Les neuf signes faciaux ciblés par le système de scorage automatique ont été préalablement évalués par trois dermatologues locaux, utilisant des Atlas référentiels du vieillissement cutané. Les 314 images obtenues furent ensuite analysées automatiquement par l'algorithme. Les sévérités des neuf signes (rides, ptose, plis, pigmentation...) ont été ensuite comparées à celles établies par les dermatologues, considérées comme références absolues. RÉSULTATS: De très significatifs coefficients de corrélation (P < 0.001) ont été trouvés dans les trois cohortes entre les scores fournis par le système et ceux issus des évaluations des dermatologues des visages durant la visite des volontaires. La caméra du dos des smartphones - de meilleure résolution que la frontale - semble fournir de légèrement meilleures significativités. Cependant, bien que significativement corrélés, les signes des désordres vasculaires et des pores cutanés des joues montrent quelques disparités, dues possiblement à la diversité technique des smartphones ou celle des prises de vue, conduisant à de plus faibles coefficients de corrélation. CONCLUSION: Ce système de quantification automatique semble offrir une approche prometteuse dans l'harmonisation des évaluations dermatologiques des signes faciaux et leurs modifications liées à l'âge et/ou le suivi de traitements à vocation antivieillissement cutané.


Assuntos
Dermatologistas , Face , Pele , Adulto , Idoso , Automação , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Smartphone , População Branca , Adulto Jovem
8.
Br J Dermatol ; 179(2): 478-485, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29569229

RESUMO

BACKGROUND: Early detection is a key factor in improving survival from melanoma. Today, the clinical diagnosis of cutaneous melanoma is based mostly on visual inspection and dermoscopy. Preclinical studies in freshly excised or paraffin-embedded tissue have shown that the melanin fluorescence spectra after stepwise two-photon excitation, a process termed dermatofluoroscopy, differ between cutaneous melanoma and melanocytic naevi. However, confirmation from a larger prospective clinical study is lacking. OBJECTIVES: The primary end point of this study was to determine the diagnostic accuracy of dermatofluoroscopy in melanoma detection. Secondary end points included the collection of data for improving the computer algorithm that classifies skin lesions based on melanin fluorescence and the assessment of safety aspects. METHODS: This was a prospective, blinded, multicentre clinical study in patients with pigmented skin lesions (PSLs) indicated for excision either to rule out or to confirm cutaneous melanoma. All included lesions underwent dermoscopy and dermatofluoroscopy in vivo before lesions were excised and subjected to histopathological examination. RESULTS: In total, 369 patients and 476 PSLs were included in the final analysis. In 101 of 476 lesions (21·2%) histopathology revealed melanoma. The observed sensitivity of dermatofluoroscopy was 89·1% (90 of 101 melanomas identified), with an observed specificity of 44·8%. The positive and negative predictive values were 30·3% and 93·9%, respectively. No adverse events occurred. CONCLUSIONS: Dermatofluoroscopy is a safe and accurate diagnostic method to aid physicians in diagnosing cutaneous melanoma. Limitations arise from largely amelanotic or regressing lesions lacking sufficient melanin fluorescence.


Assuntos
Dermoscopia/métodos , Detecção Precoce de Câncer/métodos , Melanoma/diagnóstico por imagem , Neoplasias Cutâneas/diagnóstico por imagem , Adulto , Idoso , Biópsia , Dermoscopia/efeitos adversos , Dermoscopia/instrumentação , Detecção Precoce de Câncer/efeitos adversos , Detecção Precoce de Câncer/instrumentação , Estudos de Viabilidade , Feminino , Fluoroscopia/efeitos adversos , Fluoroscopia/instrumentação , Fluoroscopia/métodos , Humanos , Melanoma/patologia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade , Pele/diagnóstico por imagem , Pele/patologia , Neoplasias Cutâneas/patologia
9.
J Chem Phys ; 149(4): 044902, 2018 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-30068172

RESUMO

Viscoelastic response in terms of the complex shear modulus G*(ω) of the linear polymers poly(ethylene-alt-propylene), poly(isoprene), and poly(butadiene) is studied for molar masses (M) from 3k up to 1000k and over a wide temperature range starting from the glass transition temperature Tg (174 K-373 K). Master curves G'(ωτα) and G″(ωτα) are constructed for the polymer-specific relaxation. Segmental relaxation occurring close to Tg is independently addressed by single spectra. Altogether, viscoelastic response is effectively studied over 14 decades in frequency. The structural relaxation time τα used for scaling is taken from dielectric spectra. We suggest a derivative method for identifying the different power-law regimes and their exponents along G″(ωτα) ∝ ωε″. The exponent ε″ = ε″(ωτα) ≡ d ln G″(ωτα)/d ln(ωτα) reveals more details compared to conventional analyses and displays high similarity among the polymers. Within a simple scaling model, the original tube-reptation model is extended to include contour length fluctuations (CLFs). The model reproduces all signatures of the quantitative theory by Likhtman and McLeish. The characteristic times and power-law exponents are rediscovered in ε″(ωτα). The high-frequency flank of the terminal relaxation closely follows the prediction for CLF (ε″ = -0.25), i.e., G″(ω) ∝ ω-0.21±0.02. At lower frequencies, a second regime with lower exponent ε″ is observed signaling the crossover to coherent reptation. Application of the full Likhtman-McLeish calculation provides a quantitative interpolation of ε″(ωτα) at frequencies below those of the Rouse regime. The derivative method also allows identifying the entanglement time τe. However, as the exponent in the Rouse regime (ωτe > 1) varies along εeRouse = 0.66 ± 0.04 (off the Rouse prediction εRouse = 0.5) and that at ωτe < 1 is similar, only a weak manifestation of the crossover at τe is found at highest M. Yet, calculating τe/τα= (M/Mo)2, we find good agreement among the polymers when discussing ε″(ωτe). The terminal relaxation time τt is directly read off from ε″(ωτα). Plotting τt/τe as a function of Z = M/Me, we find universal behavior as predicted by the TR model. The M dependence crosses over from an exponent significantly larger than 3.0 at intermediate M to an exponent approaching 3.0 at highest M in agreement with previous reports. The frequency of the minimum in G″(ωτα) scales as τmin ∝ M1.0±0.1. An M-independent frequency marks the crossover to glassy relaxation at the highest frequencies. Independent of the amplitude of G″(ω), which may be related to sample-to-sample differences, the derivative method is a versatile tool to provide a detailed phenomenological analysis of the viscoelastic response of complex liquids.

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