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1.
Clin Dermatol ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38880357

RESUMO

The ethical implications of medical schools or any of their academic departments accepting large corporate donations, mainly from pharmaceutical companies, have been long debated. Although such contributions are common in other graduate institutions, medical schools must be convinced about potential conflicts of interest and public opinion. We re-explore the benefits these kinds of gifts would afford for improved educational and research resources against the ethical dilemmas this kind of donation would present and concerns about public perception and actual conflict of interest. Using the principles of beneficence, nonmaleficence, autonomy, and distributive justice, we discuss the physicians' obligations and conceivable patient backlash that may ensue. Ultimately, we recognize the necessity for financial resources to support academic missions but contend that health care facilities and medical education must be equipped while ensuring a complete lack of bias in sponsorship.

2.
J Biomed Opt ; 28(8): 086003, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37638107

RESUMO

Significance: The quantification of protoporphyrin IX (PpIX) in skin can be used to study photodynamic therapy (PDT) treatments, understand porphyrin mechanisms, and enhance preoperative mapping of non-melanoma skin cancers. Aim: We aim to develop a smartphone-based imager for performing simultaneous radiometric fluorescence (FL) and white light (WL) imaging to study the baseline levels, accumulation, and photobleaching of PpIX in skin. Approach: A smartphone-based dual FL and WL imager (sDUO) is introduced alongside new radiometric calibration methods for providing SI-units of measurements in both pre-clinical and clinical settings. These radiometric measurements and corresponding PpIX concentration estimations are applied to clinical measurements to understand mechanistic differences between PDT treatments, accumulation differences between normal tissue and actinic keratosis lesions, and the correlation of photosensitizer concentrations to treatment outcomes. Results: The sDUO alongside the developed methods provided radiometric FL measurements (nW/cm2) with a demonstrated sub nanomolar PpIX sensitivity in 1% intralipid phantoms. Patients undergoing PDT treatment of actinic keratosis (AK) lesions were imaged, capturing the increase and subsequent decrease in FL associated with the incubation and irradiation timepoints of lamp-based PDT. Furthermore, the clinical measurements showed mechanistic differences in new daylight-based treatment modalities alongside the selective accumulation of PpIX within AK lesions. The use of the radiometric calibration enabled the reporting of detected PpIX FL in units of nW/cm2 with the use of liquid phantom measurements allowing for the estimation of in-vivo molar concentrations of skin PpIX. Conclusions: The phantom, pre-clinical, and clinical measurements demonstrated the capability of the sDUO to provide quantitative measurements of PpIX FL. The results demonstrate the use of the sDUO for the quantification of PpIX accumulation and photobleaching in a clinical setting, with implications for improving the diagnosis and treatment of various skin conditions.


Assuntos
Ceratose Actínica , Humanos , Ceratose Actínica/diagnóstico por imagem , Ceratose Actínica/tratamento farmacológico , Smartphone , Pele/diagnóstico por imagem , Luz
3.
Photodiagnosis Photodyn Ther ; 30: 101790, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32344195

RESUMO

BACKGROUND: Hypoxic lesions often respond poorly to cancer therapies. Particularly, photodynamic therapy (PDT) consumes oxygen in treated tissues, which in turn lowers its efficacy. Tools for online monitoring of intracellular pO2 are desirable. METHODS: The pO2 changes were tracked during photodynamic therapy (PDT) with δ-aminolevulinic acid (ALA) in mouse skin, xenograft tumors, and human skin. ALA was applied either topically as Ameluz cream or systemically by injection. Mitochondrial pO2 was quantified by time-gated lifetime-based imaging of delayed fluorescence (DF) of protoporphyrin IX (PpIX). RESULTS: pO2-weighted images were obtained with capture-times of several seconds, radiant exposures near 10 mJ/cm2, spatial resolution of 0.3 mm, and a broad dynamic range 1-50 mmHg, corresponding to DF lifetimes ≈20-2000 µs. The dose-rate effect on oxygen consumption was investigated in mouse skin. A fluence rate of 1.2 mW/cm2 did not cause any appreciable oxygen depletion, whereas 6 mW/cm2 and 12 mW/cm2 caused severe oxygen depletion after radiant exposures of only 0.4-0.8 J/cm2 and <0.2 J/cm2, respectively. Reoxygenation after PDT was studied too. With a 5 J/cm2 radiant exposure, the recovery times were 10-60 min, whereas with 2 J/cm2 they were only 1-6 min. pO2 distribution was spatially non-uniform at (sub)-millimeter scale, which underlines the necessity of tracking pO2 changes by imaging rather than point-detection. CONCLUSIONS: Time-gated imaging of PpIX DF seems to be a unique tool for direct online monitoring of pO2 changes during PDT with a promising potential for research purposes as well as for comparatively easy clinical translation to improve efficacy in PDT treatment.


Assuntos
Ácido Aminolevulínico/farmacologia , Consumo de Oxigênio/efeitos dos fármacos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Protoporfirinas/farmacocinética , Ácido Aminolevulínico/farmacocinética , Animais , Humanos , Camundongos , Mitocôndrias/efeitos dos fármacos , Imagem Óptica , Oxigênio/metabolismo , Fármacos Fotossensibilizantes/farmacocinética
4.
Am J Dermatopathol ; 39(1): 53-55, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27149335

RESUMO

Abdominal wall transplants are relatively new procedures that are frequently performed in conjunction with multivisceral transplants. The skin of the abdominal wall transplant is often the first site for graft rejection to manifest itself. Prompt recognition can lead to appropriate treatment before the involvement of the underlying viscera. However, the signs of graft rejection are nonspecific and can overlap with other entities. We present a case of a patient who received a multivisceral and abdominal wall transplant from 2 different donors, who presented with acute and eventually chronic graft rejection of the abdominal wall graft. Serial biopsies performed during the course of her treatment demonstrated progressive sclerotic changes in the dermis. Because these changes were confined to the abdominal wall graft, they could represent either chronic graft rejection or graft-versus-graft disease. To date, graft-versus-graft disease has not been documented in these patients. This case illustrates the possibility that patients with multidonor transplants may be at an increased risk for graft failure secondary to multiple potential etiologies.


Assuntos
Parede Abdominal/cirurgia , Rejeição de Enxerto/patologia , Doença Enxerto-Hospedeiro/patologia , Transplante de Pele/efeitos adversos , Pele/patologia , Parede Abdominal/patologia , Biópsia , Doença Crônica , Diagnóstico Diferencial , Feminino , Humanos , Valor Preditivo dos Testes , Esclerose , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
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