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1.
Eur Heart J ; 45(17): 1553-1567, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38486376

RESUMO

BACKGROUND AND AIMS: The ecto-nucleoside triphosphate diphosphohydrolases of the CD39 family degrade ATP and ADP into AMP, which is converted into adenosine by the extracellular CD73/ecto-5-nucleotidase. This pathway has been explored in antithrombotic treatments but little in myocardial protection. We have investigated whether the administration of solCD39L3 (AZD3366) confers additional cardioprotection to that of ticagrelor alone in a pre-clinical model of myocardial infarction (MI). METHODS: Ticagrelor-treated pigs underwent balloon-induced MI (90 min) and, before reperfusion, received intravenously either vehicle, 1 mg/kg AZD3366 or 3 mg/kg AZD3366. All animals received ticagrelor twice daily for 42 days. A non-treated MI group was run as a control. Serial cardiac magnetic resonance (baseline, Day 3 and Day 42 post-MI), light transmittance aggregometry, bleeding time, and histological and molecular analyses were performed. RESULTS: Ticagrelor reduced oedema formation and infarct size at Day 3 post-MI vs. controls. A 3 mg/kg AZD3366 provided an additional 45% reduction in oedema and infarct size compared with ticagrelor and a 70% reduction vs. controls (P < .05). At Day 42, infarct size declined in all ticagrelor-administered pigs, particularly in 3 mg/kg AZD3366-treated pigs (P < .05). Left ventricular ejection fraction was diminished at Day 3 in placebo pigs and worsened at Day 42, whereas it remained unaltered in ticagrelor ± AZD3366-administered animals. Pigs administered with 3 mg/kg AZD3366 displayed higher left ventricular ejection fraction upon dobutamine stress at Day 3 and minimal dysfunctional segmental contraction at Day 42 (χ2P < .05 vs. all). Cardiac and systemic molecular readouts supported these benefits. Interestingly, AZD3366 abolished ADP-induced light transmittance aggregometry without affecting bleeding time. CONCLUSIONS: Infusion of AZD3366 on top of ticagrelor leads to enhanced cardioprotection compared with ticagrelor alone.


Assuntos
Adenosina Trifosfatases , Apirase , Infarto do Miocárdio , Ticagrelor , Animais , Humanos , Masculino , Adenosina/análogos & derivados , Adenosina/farmacologia , Antígenos CD , Apirase/metabolismo , Cardiotônicos/farmacologia , Cardiotônicos/uso terapêutico , Modelos Animais de Doenças , Infarto do Miocárdio/tratamento farmacológico , Agregação Plaquetária/efeitos dos fármacos , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Suínos , Ticagrelor/farmacologia , Ticagrelor/uso terapêutico , Adenosina Trifosfatases/farmacologia , Adenosina Trifosfatases/uso terapêutico
2.
Radiographics ; 44(4): e230160, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38483831

RESUMO

The epicardial space (ES) is the anatomic region located between the myocardium and the pericardium. This space includes the visceral pericardium and the epicardial fat that contains the epicardial coronary arteries, cardiac veins, lymphatic channels, and nerves. The epicardial fat represents the main component of the ES. This fat deposit has been a focus of research in recent years owing to its properties and relationship with coronary gossypiboma plaque and atrial fibrillation. Although this region is sometimes forgotten, a broad spectrum of lesions can be found in the ES and can be divided into neoplastic and nonneoplastic categories. Epicardial neoplastic lesions include lipoma, paraganglioma, metastases, angiosarcoma, and lymphoma. Epicardial nonneoplastic lesions encompass inflammatory infiltrative disorders, such as immunoglobulin G4-related disease and Erdheim-Chester disease, along with hydatidosis, abscesses, coronary abnormalities, pseudoaneurysms, hematoma, lipomatosis, and gossypiboma. Initial imaging of epicardial lesions may be performed with echocardiography, but CT and cardiac MRI are the best imaging modalities to help characterize epicardial lesions. Due to the nonspecific onset of signs and symptoms, the clinical history of a patient can play a crucial role in the diagnosis. A history of malignancy, multisystem diseases, prior trauma, myocardial infarction, or cardiac surgery can help narrow the differential diagnosis. The diagnostic approach to epicardial lesions should be made on the basis of the specific location, characteristic imaging features, and clinical background. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.


Assuntos
Tecido Adiposo , Corpos Estranhos , Humanos , Tecido Adiposo/patologia , Pericárdio/diagnóstico por imagem , Miocárdio , Ecocardiografia/métodos
3.
Tour Manag ; 88: 104395, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34720321

RESUMO

This paper analyses the influence that the initial actions and strategies pursued by hotel managers have on the recovery of occupancy after a crisis such as the COVID-19 pandemic. To do this, a specific survey is carried out on managers of Spanish hotels. The main findings show that labour actions, especially plans for temporary employment regulations, innovation and differentiation strategies, reorientation to closer markets and obtaining information from official sources as a guarantee of their certainty, are the measures that have a greater impact on the possibilities of recovering hotel activity. In addition, government measures that contribute to the improvement of the financial situation of firms can also play a relevant role in hotel recovery.

4.
Radiographics ; 41(1): 8-31, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33337967

RESUMO

Acute chest pain is a common reason for visits to the emergency department. It is important to distinguish among the various causes of acute chest pain, because treatment and prognosis are substantially different among the various conditions. It is critical to exclude acute coronary syndrome (ACS), which is a major cause of hospitalization, death, and health care costs worldwide. Myocardial ischemia is defined as potential myocyte death secondary to an imbalance between oxygen supply and demand due to obstruction of an epicardial coronary artery. Unobstructed coronary artery disease can have cardiac causes (eg, myocarditis, myocardial infarction with nonobstructed coronary arteries, and Takotsubo cardiomyopathy), and noncardiac diseases can manifest with acute chest pain and increased serum cardiac biomarker levels. In the emergency department, cardiac MRI may aid in the identification of patients with non-ST-segment elevation myocardial infarction or unstable angina or ACS with unobstructed coronary artery disease, if the patient's clinical history is known to be atypical. Also, cardiac MRI is excellent for risk stratification of patients for adverse left ventricular remodeling or major adverse cardiac events. Cardiac MRI should be performed early in the course of the disease (<2 weeks after onset of symptoms). Steady-state free-precession T2-weighted MRI with late gadolinium enhancement is the mainstay of the cardiac MRI protocol. Further sequences can be used to analyze the different pathophysiologic subjacent mechanisms of the disease, such as microvascular obstruction or intramyocardial hemorrhage. Finally, cardiac MRI may provide several prognostic biomarkers that help in follow-up of these patients. Online supplemental material is available for this article. ©RSNA, 2020.


Assuntos
Meios de Contraste , Infarto do Miocárdio , Dor no Peito/diagnóstico por imagem , Dor no Peito/etiologia , Gadolínio , Humanos , Imageamento por Ressonância Magnética
5.
Am J Ther ; 27(1): e13-e23, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31876562

RESUMO

BACKGROUND: Historical description of first insulin trials just after its discovery. AREAS OF UNCERTAINTY: The review includes first initiatives of insulin treatment. The probability of other trials, not reported to the Insulin Committee of the University of Toronto and conducted in the years 1922 and 1923, is quite low. DATA SOURCES: (1) Archival Collections, University of Toronto: Insulin Discovery and Early Developments of Insulin (University of Toronto Libraries digital special collection, with a particular section entitled "From a Patient's Point of View" containing letters, patient charts, newspaper clippings, and photographs). (2) Thomas Fisher Rare Book Library: Academy of Medicine Collection, F. G. Banting Papers, C. H. Best Papers, J. B.Collip Papers, W. R. Feasby Papers, E. Hugues Papers, J. J. R. Macleod Papers. (3) National Library of Medicine: PubMed search for the topic of history of insulin, History of Medicine-on syllabus archive. (4) Selected Journals for History of Medicine: Bulletin of the History of Medicine, Journal of the History of Medicine and Allied Sciences, Medical History. (5) Selected books: The Discovery of Insulin (M. Bliss); Diabetes, Its Medical and Cultural History (D. von Engelhardt); H. C. Hagedorn and Danish Insulin (T.Deckert), Continuing Quest (W. A. Tomkins). THERAPEUTIC ADVANCES: This historical review shows the quick progress from impure pancreatic extract to the selective isoelectric precipitation of the hormone, which made possible the introduction of insulin in the clinic. CONCLUSIONS: The coordination between the Departments of Physiology (Connaught Laboratories) and Medicine (Toronto General Hospital) was essential for the discovery and implementation of insulin therapy. The Insulin Committee was decisive for the negotiation with the pharmaceutical industry, the purification, grand-scale production, patents' achievement, and provision of licenses to expert clinicians and prestigious health centers. At the end of the year 1923, insulin treatment was already extended to Europe (mainly Scandinavia, Great Britain, and Spain). Insulin discovery and treatment changed the clinical spectrum of diabetes.


Assuntos
Diabetes Mellitus/história , Hipoglicemiantes/história , Insulina/história , Diabetes Mellitus/tratamento farmacológico , História do Século XX , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico
6.
Am J Ther ; 27(1): e1-e12, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31599767

RESUMO

BACKGROUND: Historical review on the early development of organotherapy for diabetes [pancreatic extracts (PE)] and its relationship with the social and political circumstances. AREAS OF UNCERTAINTY: The diagnosis of diabetes relied only in the presence of glycosuria and cardinal symptoms. Blood glucose determinations were not regularly available, requiring large volumes for sampling. Micromethods for glycemia were developed just in the last years of the investigated period. Hypoglycemia remains undiscovered. Isolation and purification of PE were difficult tasks due to the unknown chemical structure of the antidiabetic hormone. DATA SOURCES: (1) Berliner Medizinhistoriches Museum der Charité (Humboldt University). (2) GeDenKort Charité-Wissenschaft in Verantwortung. (3) Geheim Staatsarchiv Preußischer Kulturbesitz. (4) Archival Collections, University of Toronto: Thomas Fisher Rare Book Library. Academy of Medicine Collection, F. G. Banting Papers, C. H. Best Papers, J. J. R. Macleod Papers. (5) National Library of Medicine: Pubmed search for the topic of history of insulin. History of Medicine-on syllabus archive. (6) Selected books: The Discovery of Insulin (M. Bliss); Diabetes, Its Medical and Cultural History (D. von Engelhardt); Brown-Séquard (M. J. Aminoff); Diabetes: The Biography (R. Tattersall); The Endocrine Organs (E. Schäfer); The Internal Secretions (E. Gley); Health, race and German politics between national unification and Nazism, 1870-1945 (P. Weindling). THERAPEUTIC ADVANCES: Demonstration that diabetes is a pancreatic disease. The outstanding progress of medical physiology led to the birth of endocrinology and the key concepts of homeostasis. Experimental scientists designed new procedures for complete pancreatectomy and elaboration of PE containing the antidiabetic principle. Organotherapy achieved complete success in the treatment of myxedema and partial success in the treatment of experimental and clinical diabetes. CONCLUSIONS: The organotherapy of diabetes was an obliged step to facilitate the identification of the antidiabetic hormone. Organotherapy of diabetes was a paradigm for the integration of basic and applied knowledge about hormone action and development of endocrine pharmacology.


Assuntos
Diabetes Mellitus/história , Hipoglicemiantes/história , Extratos Pancreáticos/história , Glicemia , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/tratamento farmacológico , Endocrinologia/história , História do Século XIX , História do Século XX , Humanos , Hipoglicemiantes/uso terapêutico , Pâncreas/fisiopatologia , Extratos Pancreáticos/uso terapêutico
7.
Mycopathologia ; 185(4): 639-652, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32564177

RESUMO

Broad-spectrum antifungal prophylaxis is currently considered the standard of care for adults with de novo AML for the prevention of invasive fungal infections (IFIs), especially invasive pulmonary aspergillosis (IPA). Because fluconazole has been used in our center as anti-yeast prophylaxis, we sought to analyze in detail the incidence of IFIs over a 17-year period, as well as their impact on outcome. A standardized protocol of patient management, including serum galactomannan screening and thoracic CT-guided diagnostic-driven antifungal therapy, was used in all patients. A total of 214 consecutive adults with de novo AML who were treated in 3 CETLAM (Grupo Cooperativo para el Estudio y Tratamiento de las Leucemias Agudas y Mielodisplasias) protocols from 2002 to 2018 were included. The 90-day incidence of any IFI (including possible cases) was 11% (95% CI 4-15%), most cases occurred during induction chemotherapy (8%, 95% CI 4-12%), and most cases were probable/proven IPA (8%, 95% CI 3-13%). Developing an IFI during induction and consolidation had no impact on 1-year survival. A case-control study with 23 cases of IPA and 69 controls identified induction/re-induction chemotherapy, chronic pulmonary disease and age > 60 years/poor baseline performance status as potential pretreatment risk factors. The current study proves that inpatient induction and consolidation chemotherapy for de novo AML can be given in areas with "a priori" high-burden of airborne molds with fluconazole prophylaxis, while the selective use of anti-mold prophylaxis in patients at very high risk may further reduce the incidence of IFI in this specific clinical scenario.


Assuntos
Antifúngicos , Quimioterapia de Consolidação , Infecções Fúngicas Invasivas , Leucemia Mieloide Aguda , Adulto , Antifúngicos/uso terapêutico , Estudos de Casos e Controles , Humanos , Infecções Fúngicas Invasivas/epidemiologia , Infecções Fúngicas Invasivas/prevenção & controle , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/microbiologia , Pessoa de Meia-Idade , Estudos Retrospectivos
8.
Langmuir ; 35(3): 678-686, 2019 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-30580527

RESUMO

Phasins, the major proteins coating polyhydroxyalkanoate (PHA) granules, have been proposed as suitable biosurfactants for multiple applications because of their amphiphilic nature. In this work, we analyzed the interfacial activity of the amphiphilic α-helical phasin PhaF from Pseudomonas putida KT2440 at different hydrophobic-hydrophilic interfacial environments. The binding of PhaF to surfaces containing PHA or phospholipids, postulated as structural components of PHA granules, was confirmed in vitro using supported lipid bilayers and confocal microscopy, with polyhydroxyoctanoate- co-hexanoate P(HO- co-HHx) and Escherichia coli lipid extract as model systems. The surfactant-like capabilities of PhaF were determined by measuring changes in surface pressure in Langmuir devices. PhaF spontaneously adsorbed at the air-water interface, reducing the surface tension from 72 mN/m (water surface tension at 25 °C) to 50 mN/m. The differences in the adsorption of the protein in the presence of different phospholipid films showed a marked preference for phosphatidylglycerol species, such as 1-palmitoyl-2-oleoyl- sn-glycero-3-phosphoglycerol. The PHA-binding domain of PhaF (BioF) conserved a similar surface activity to PhaF, suggesting that it is responsible for the surfactant properties of the whole protein. These new findings not only increase our knowledge about the role of phasins in the PHA machinery but also open new outlooks for the application of these proteins as biosurfactants.


Assuntos
Proteínas de Bactérias/química , Pseudomonas putida/química , Tensoativos/química , Adsorção , Proteínas de Bactérias/isolamento & purificação , Escherichia coli/genética , Interações Hidrofóbicas e Hidrofílicas , Bicamadas Lipídicas/química , Domínios Proteicos , Tensoativos/isolamento & purificação , Lipossomas Unilamelares/química
9.
J Ultrasound Med ; 38(3): 761-765, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30171619

RESUMO

OBJECTIVES: To assess the feasibility of gastrointestinal endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) for histologic confirmation of cancer recurrence in women with gynecologic cancer. METHODS: This work was a retrospective cohort study comprising 46 consecutive women treated for gynecologic cancer and suspected of having a deep pelvic or abdominal recurrence on ultrasound imaging, computed tomography, positron emission tomography-computed tomography, or magnetic resonance imaging, evaluated at our institution from January 2010 to December 2017. Primary cancer was ovarian (n = 22), cervical (n = 13), endometrial (n = 4), sarcoma (n = 4), and other (n = 3). All women underwent EUS examinations for locating the lesion and guiding FNA. The results of FNA (benign/malignant) were assessed. Procedure-related complications were recorded. RESULTS: The patients' mean age was 57.8 years. A total of 66 procedures were performed. Eleven women underwent 2 procedures; 2 women underwent 3 procedures; and 1 woman underwent 6 procedures at different times during the study period. In 1 case, no lesion was detected on the EUS assessment, and in 2 cases, FNA was not successful. Most lesions were located in the retroperitoneum or involved the intestine. Fine-needle aspiration could be performed in 63 cases (94.5%). Cytologic samples were adequate in 62 of 63 (98.4%). Recurrence was confirmed in 56 cases (90.3%) and ruled out in 6 (9.7%). No patient had any complication related to the procedure. CONCLUSIONS: Endoscopic ultrasound-guided FNA is a minimally invasive, feasible, and safe technique for confirming pelvic/abdominal recurrence of gynecologic cancer.


Assuntos
Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Neoplasias Gastrointestinais/diagnóstico por imagem , Trato Gastrointestinal/diagnóstico por imagem , Trato Gastrointestinal/patologia , Neoplasias dos Genitais Femininos/patologia , Segunda Neoplasia Primária/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Estudos de Viabilidade , Feminino , Neoplasias Gastrointestinais/patologia , Neoplasias Gastrointestinais/secundário , Humanos , Pessoa de Meia-Idade , Segunda Neoplasia Primária/patologia , Estudos Retrospectivos , Adulto Jovem
10.
Circulation ; 134(22): 1708-1719, 2016 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-27789556

RESUMO

BACKGROUND: The P2Y12 receptor antagonist ticagrelor has been shown to be clinically superior to clopidogrel. Although the underlying mechanisms remain elusive, ticagrelor may exert off-target effects through adenosine-related mechanisms. We aimed to investigate whether ticagrelor reduces myocardial injury to a greater extent than clopidogrel after myocardial infarction (MI) at a similar level of platelet inhibition and to determine the underlying mechanisms. METHODS: Pigs received the following before MI induction: (1) placebo-control; (2) a loading dose of clopidogrel (600 mg); (3) a loading dose of ticagrelor (180 mg); or (4) a loading dose of ticagrelor followed by an adenosine A1/A2-receptor antagonist [8-(p-sulfophenyl)theophylline, 4 mg/kg intravenous] to determine the potential contribution of adenosine in ticagrelor-related cardioprotection. Animals received the corresponding maintenance doses of the antiplatelet agents during the following 24 hours and underwent 3T-cardiac MRI analysis. Platelet inhibition was monitored by ADP-induced platelet aggregation. In the myocardium, we assessed the expression and activation of proteins known to modulate edema formation, including aquaporin-4 and AMP-activated protein kinase and its downstream effectors CD36 and endothelial nitric oxide synthase and cyclooxygenase-2 activity. RESULTS: Clopidogrel and ticagrelor exerted a high and consistent antiplatelet effect (68.2% and 62.2% of platelet inhibition, respectively, on challenge with 20 µmol/L ADP) that persisted up to 24 hours post-MI (P<0.05). All groups showed comparable myocardial area-at-risk and cardiac worsening after MI induction. 3T-Cardiac MRI analysis revealed that clopidogrel- and ticagrelor-treated animals had a significantly smaller extent of MI than placebo-control animals (15.7 g left ventricle and 12.0 g left ventricle versus 22.8 g left ventricle, respectively). Yet, ticagrelor reduced infarct size to a significantly greater extent than clopidogrel (further 23.5% reduction; P=0.0026), an effect supported by troponin-I assessment and histopathologic analysis (P=0.0021). Furthermore, in comparison with clopidogrel, ticagrelor significantly diminished myocardial edema by 24.5% (P=0.004), which correlated with infarct mass (r=0.73; P<0.001). 8-(p-Sulfophenyl)theophylline administration abolished the cardioprotective effects of ticagrelor over clopidogrel. At a molecular level, aquaporin-4 expression decreased and the expression and activation of AMP-activated protein kinase signaling and cyclooxygenase-2 increased in the ischemic myocardium of ticagrelor- versus clopidogrel-treated animals (P<0.05). These protein changes were not observed in those animals administered the adenosine receptor blocker 8-(p-sulfophenyl)theophylline. CONCLUSIONS: Ticagrelor, beyond its antiplatelet efficacy, exerts cardioprotective effects by reducing necrotic injury and edema formation via adenosine-dependent mechanisms.


Assuntos
Adenosina/análogos & derivados , Cardiotônicos/farmacologia , Infarto do Miocárdio/tratamento farmacológico , Ticlopidina/análogos & derivados , Adenosina/farmacologia , Animais , Plaquetas/efeitos dos fármacos , Clopidogrel , Ciclo-Oxigenase 2/metabolismo , Infarto do Miocárdio/enzimologia , Infarto do Miocárdio/patologia , Inibidores da Agregação Plaquetária/farmacologia , Distribuição Aleatória , Suínos , Ticagrelor , Ticlopidina/farmacologia
11.
Biochim Biophys Acta Biomembr ; 1859(9 Pt B): 1740-1748, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28450046

RESUMO

Pulmonary surfactant is a membrane-based lipid-protein system essential for the process of breathing, which coats and stabilizes the whole respiratory surface and possesses exceptional biophysical properties. It constitutes the first barrier against the entry of pathogens and harmful particles in the alveolar region, extended through the lungs, but on the other hand, it can offer novel possibilities as a shuttle for the delivery of drugs and nanocarriers. The advances in nanotechnology are opening the doors to new diagnostic and therapeutic avenues, which are not accessible by means of the current approaches. In this context, the pulmonary route is called to become a powerful way of entry for innovative treatments based on nanotechnology. In this review, the anatomy of the respiratory system and its properties for drug entry are first revisited, as well as some current strategies that use the respiratory route for both local and peripheral action. Then, a brief overview is presented on what pulmonary surfactant is, how it works and why it could be used as a drug delivery vehicle. Finally, the review is closed with a description of the development of nanocarriers in the lung context and their interaction with endogenous and clinical pulmonary surfactants. This article is part of a Special Issue entitled: Membrane Lipid Therapy: Drugs Targeting Biomembranes edited by Pablo V. Escribá.


Assuntos
Sistemas de Liberação de Medicamentos , Nanomedicina , Surfactantes Pulmonares/administração & dosagem , Humanos , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas , Tamanho da Partícula , Surfactantes Pulmonares/toxicidade
12.
Langmuir ; 33(32): 7929-7939, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28738158

RESUMO

Pulmonary surfactant is a crucial system to stabilize the respiratory air-liquid interface. Furthermore, pulmonary surfactant has been proposed as an effective method for targeting drugs to the lungs. However, few studies have examined in detail the mechanisms of incorporation of drugs into surfactant, the impact of the presence of drugs on pulmonary surfactant performance at the interface under physiologically meaningful conditions, or the ability of pulmonary surfactant to use the air-liquid interface to vehiculise drugs to long distances. This study focuses on the ability of pulmonary surfactant to interfacially vehiculize corticosteroids such as beclomethasone dipropionate (BDP) or Budesonide (BUD) as model drugs. The main objectives have been to (a) characterize the incorporation of corticosteroids into natural and synthetic surfactants, (b) evaluate whether the presence of corticosteroids affects surfactant functionality, and (c) determine whether surfactant preparations enable the efficient spreading and distribution of BDP and BUD along the air-liquid interface. We have compared the performance of a purified surfactant from porcine lungs and two clinical surfactants: Poractant alfa, a natural surfactant of animal origin extensively used to treat premature babies, and CHF5633, a new synthetic surfactant preparation currently under clinical trials. Both, natural and clinical surfactants spontaneously incorporated corticosteroids up to at least 10% by mass with respect to phospholipid content. The presence of the drugs did not interfere with their ability to efficiently adsorb into air-liquid interfaces and form surface active films able to reach and sustain very low surface tensions (<2 mN/m) under compression-expansion cycling mimicking breathing dynamics. Furthermore, the combination of clinical surfactant with corticosteroids efficiently promoted the active diffusion of the drug to long distances along the air-liquid interface. This effect could not be mimicked by vehiculisation of corticosteroids in liposomes or in micellar emulsions similar to the formulations currently in use to deliver anti-inflammatory corticosteroids through inhalation.


Assuntos
Surfactantes Pulmonares/química , Corticosteroides , Animais , Emulsões , Pulmão , Tensão Superficial , Suínos
13.
Acta Oncol ; 53(1): 96-102, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24032443

RESUMO

BACKGROUND: To assess treatment tolerance by patients treated with a dose-adapted salvage radiotherapy (SRT) protocol based on an multiparametric endorectal magnetic resonance imaging (erMRI) failure definition model after radical prostatectomy (RP). MATERIAL AND METHODS: A total of 171 prostate cancer patients recurring after RP undergoing erMRI before SRT were analyzed. A median dose of 64 Gy was delivered to the prostatic bed (PB) with, in addition, a boost of 10 Gy to the suspected relapse as visualized on erMRI in 131 patients (76.6%). Genitourinary (GU) and gastrointestinal (GI) toxicities were scored using the RTOG scale. RESULTS: Grade ≥ 3 GU and GI acute toxicity were observed in three and zero patients, respectively. The four-year grade ≥ 2 and ≥ 3 late GU and GI toxicity-free survival rates (109 patients with at least two years of follow-up) were 83.9 ± 4.7% and 87.1 ± 4.2%, and 92.1 ± 3.6% and 97.5 ± 1.7%, respectively. Boost (p = 0.048) and grade ≥ 2 acute GU toxicity (p = 0.008) were independently correlated with grade ≥ 2 late GU toxicity on multivariate analysis. CONCLUSIONS: A dose-adapted, erMRI-based SRT approach treating the PB with a boost to the suspected local recurrence may potentially improve the therapeutic ratio by selecting patients that are most likely expected to benefit from SRT doses above 70 Gy as well as by reducing the size of the highest-dose target volume. Further prospective trials are needed to investigate the use of erMRI in SRT as well as the role of dose-adapted protocols and the best fractionation schedule.


Assuntos
Fracionamento da Dose de Radiação , Gastroenteropatias/prevenção & controle , Imageamento por Ressonância Magnética/métodos , Doenças Urogenitais Masculinas/prevenção & controle , Recidiva Local de Neoplasia/prevenção & controle , Prostatectomia , Neoplasias da Próstata/radioterapia , Terapia de Salvação , Adulto , Idoso , Idoso de 80 Anos ou mais , Seguimentos , Gastroenteropatias/etiologia , Gastroenteropatias/patologia , Humanos , Masculino , Doenças Urogenitais Masculinas/etiologia , Doenças Urogenitais Masculinas/patologia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/etiologia , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia
14.
Ann Biomed Eng ; 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38853207

RESUMO

Rotational mechanics is a fundamental determinant of left ventricular ejection fraction (LVEF). The coding system currently employed in clinical practice does not distinguish between rotational patterns. We propose an alternative coding system that makes possible to identify the rotational pattern of the LV and relate it to myocardial function. Echocardiographic images were used to generate speckle tracking-derived transmural global longitudinal strain (tGLS) and rotational parameters. The existence of twist (basal and apical rotations in opposite directions) is expressed as a rotational gradient with a positive value that is the sum of the basal and apical rotation angles. Conversely, when there is rigid rotation (basal and apical rotations in the same direction) the resulting gradient is assigned a negative value that is the subtraction between the two rotation angles. The rotational patterns were evaluated in 87 healthy subjects and 248 patients with LV hypertrophy (LVH) and contrasted with their myocardial function. Our approach allowed us to distinguish between the different rotational patterns. Twist pattern was present in healthy controls and 104 patients with LVH and normal myocardial function (tGLS ≥ 17%, both). Among 144 patients with LVH and myocardial dysfunction (tGLS < 17%), twist was detected in 83.3% and rigid rotation in 16.7%. LVEF was < 50% in 34.7%, and all patients with rigid rotation had a LVEF < 50%. The gradient rotational values showed a close relationship with LVEF (r = 0.73; p < 0.001). The proposed coding system allows us to identify the rotational patterns of the LV and to relate their values with LVEF.

16.
Acta Diabetol ; 60(11): 1513-1530, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37407772

RESUMO

AIMS: Since the Nobel Prize in Physiology or Medicine was awarded in 1923 to FG Banting and JJR Macleod, many voices have been raised against this decision. The bitterest protest was that of the Romanian scientist Nicolae C. Paulescu. In 2002, The Romanian Academy of Sciences, the European Association for the Study of Diabetes (EASD) and the International Diabetes Federation (IDF) planned to hold a series of academic events the following year in Paris to acknowledge Paulescu's scientific merits in the discovery of the antidiabetic hormone. However, the initiative was cancelled in August 2003, when the European Center of the Simon Wiesenthal Foundation (SWC) accused Paulescu of being antisemitic. The authors of this manuscript have decided to approach "the Paulescu case" from its double aspect, scientific and sociopolitical, to analyze the circumstances surrounding the discovery of the antidiabetic hormone, and Paulescu's alleged antisemitic past in the historical context of the Romanian nation in the interwar period. METHODS: We contacted the SWC and people related to the 2003 events in Paris. We performed a comparative review of the documents published by the Toronto group and by Paulescu and analyzed the correspondence and articles generated by international experts from the scientific community interested in the controversy. We carried out an exhaustive bibliographic search through several online catalogs (INDEXCAT, NLM Gateway, EUREKA, MEDHIST). We travelled to Bucharest, where we visited Paulescu's house-museum, interviewed a former student of the Romanian professor, and a prominent medical historian who was knowledgeable about Paulescu's scientific and political biography. Dan Angelescu†, son of Dr. Constantin Angelescu (1904-1990), Paulescu's nephew and collaborator, provided us with a copy of all the available documentation from Paulescu's personal archive. It constitutes an essential source for understanding Paulescu's personal, political and academic biography. Archives consulted: Românǎ Academy (Bucharest). Personal Archive of Paulescu, House -Museum (Bucharest)*. Romanian Jewish Heritage (Bucharest). http://romanianjewish.org/ **. Simon Wiesenthal Center (Los Angeles, CA) http://www.wiesenthal.com **. Romanian Patent Office. Oficiul de Stat pentru Invenții si Mǎrci (OSIM) (Bucharest)***. Nobel Archives (Stockholm) https://www.nobelprize.org . Internet Archive (San Francisco, CA) https://archive.org **. Wellcome Library (London) https://wellcomelibrary.org **. The European Library https://www.theeuropeanlibrary.org/ **. US National Library of Medicine, NLM historical collections http://www.nlm.nih.gov/hmd/index.html **. US. Holocaust Memorial Museum http://www.ushmm.org/ (*: archive consulted on site; **: material found in the online catalog of the archive; ***: archivists sent us digitized copies of archival material). Books consulted for information on the history of Romania and antisemitism: "Nationalist ideology and antisemitism. The case of Romanian intellectuals in the 1930s", by Leon Volovici; "The mystique of ultranationalism: History of the Iron Guard, Romania, 1919-1941" by Francisco Vega; "Romania 1866-1947", by Keith Hitchins; "History of Romania. Compendium", by Ioan-Aurel Pop and Joan Bolovan; "The Holocaust in Romania. The destruction of Jews and Gypsies under the Antonescu regime, 1940-1944", by Radu Ioanid; "The Jews of East Central Europe between the World Wars", by Ezra Mendelson; "Cultural Politics in Greater Romania. Regionalism, Nation Building and Ethnic Struggle, 1918-1930", by Irina Livezeanu, and "Judeophobia. How and when it is born, where and why it survives", by Gustavo Daniel Perednik. Articles are referenced in the bibliography section at the end of the manuscript. RESULTS: A-Nicolae Paulescu developed an intense long-term research activity, which included complete pancreatectomy and preparation of a pancreatic extract (PE) containing the antidiabetic hormone he called pancreina. Parenteral administration of the PE achieved excellent results in the treatment of experimental diabetes in dogs and induction of hypoglycemia in the healthy animal. This work was initiated before 1916 and published at least eight months antedating the publication of the first article by Banting and Best (February 1922), who were acquainted with Paulescu's results, but misinterpreted them. The pancreatic extract of the two Canadian researchers, -iletin/insulin-, only achieved similar results to that of the Romanian scientist once they abandoned the use of the "degenerated pancreas" extract (ligation of the ductal system), replacing it with the pancreas of adult or fetal bovine. Pancreina and insulin were very similar. The award of the Nobel Prize in Physiology or Medicine to FG Banting and JJR Macleod in October 1923 honored the successful clinical use of insulin in patients with diabetes mellitus. Paulescu's achievements were ignored. B-Nicolae Paulescu publicly manifested his Judeophobic ideology on multiple occasions in academic and political interventions and in publications and participated with other figures from the Romanian intellectual sphere in the founding of the Uniunea Național Crestinǎ (UNC, National Christian Union) in 1922 and of the Liga Apǎrǎrii Național Cresține (LANC, League for Christian National Defense) in 1923, antisemitic far-right political parties, associated with an irrational Christian orthodoxy and hatred of Jews. Paulescu played a pivotal role in the spread of antisemitism. CONCLUSIONS: A-The Romanian scientist NC Paulescu started an intense research program aimed at the isolation of the antidiabetic hormone before 1916, including an original procedure of pancreatectomy in the dog and the elaboration of a pancreatic extract that achieved excellent results in the treatment of experimental diabetes, demonstrating its beneficial effects on the metabolism of carbohydrates, proteins and fats and reducing both glycosuria and glycemia and the urinary excretion of ketone bodies of depancreatized dogs toward normality. The results of these investigations were published in 1920 and 1921, predating the first report published by FG ​​Banting and CH Best in February 1922. It has been sufficiently demonstrated that Canadian researchers were aware of Paulescu's excellent results, mentioning them only in passing, albeit erroneously misrepresenting key results of the Romanian scientist's publication in the aforementioned seminal Canadian article. Expert historians and international scientists have recognized that the pancreatic extract that Paulescu called pancreina and that obtained by Banting and Best, insulin, were very similar. The October 1923 award of the Nobel Prize in Physiology or Medicine to FG Banting and JJR Macleod ignored Paulescu's scientific achievements in the treatment of experimental diabetes and rewarded the extraordinary advance of insulin treatment in human diabetes. B-At the end of August 2003, a few days before the date of the celebration at the Hôtel Dieu in Paris of the scheduled program of tribute to the scientific merits of NC Paulescu and his important contribution to the discovery of the antidiabetic hormone, convened by the Romanian Academy and the International Diabetes Federation, the Wiesenthal Foundation publicly accused the Romanian scientist of being an antisemite, an act that determined the cancellation of the announced events. The exhaustive investigation of the personal convictions and antisemitic behavior of Nicolae C. Paulescu has undoubtedly documented the Judeophobic ideology of the Romanian scientist, linked to his orthodox religious radicalism, manifested in multiple documents (mostly pamphlets) and interventions in collaboration with other relevant personalities of the Romanian intelligentsia of his time. Furthermore, Paulescu participated in the creation of political organizations of the most radical extreme right that played a fundamental role in the spread of antisemitism amongst the Romanian population and the university community.


Assuntos
Medicina , Prêmio Nobel , Fisiologia , Humanos , Aniversários e Eventos Especiais , Romênia
17.
Acta Diabetol ; 60(2): 163-189, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36585966

RESUMO

AIMS: The general objective has been the historiographical investigation of the organotherapy of diabetes mellitus between 1906 and 1923 in its scientific, social and political dimensions, with special emphasis on the most relevant contributions of researchers and institutions and on the controversies generated on the priority of the "discovery" of antidiabetic hormone. METHODS: We have analyzed the experimental procedures and determination of biological parameters used by researchers during the investigated period (1906-1923): pancreatic ablation techniques, induction of acinar atrophy with preservation of pancreatic islets, preparation of pancreatic extracts (PE) with antidiabetic activity, clinical chemistry procedures (glycemia, glycosuria, ketonemia, ketonuria, etc.). The field investigation has included on-site and online visits to cities, towns, buildings, laboratories, universities, museums and research centers where the reported events took place, obtaining documents, photographic images, audiovisual recordings, as well as personal interviews complementary to the documentation consulted (primary sources, critical bibliography, reference works). The documentary archival sources have been classified according to theme, including those consulted in situ with those extracted online and digitized copies received mainly by email. Among the many archives contacted, those listed below have been most useful and have been consulted on site and on repeated visits: National Library of Medicine-Historical Archives (Bethesda, MD, USA); Archives, University of Toronto and Thomas Fisher Rare Books Library (Toronto, Ontario, Canada); Francis A. County Library of Medicine, Harvard University (Boston, Mass, USA); Zentralbibliothek der Humboldt-Universität (Berlin, DE), Geheimarchiv des Preußischen Staates (Berlin, DE); Landesamt für Bürger-und Ordnungsangelegenheiten (LABO) (Berlin, DE); Arhivele Academiei Române si Universitǎții Carol Davila (Bucharest, RO). MAIN RESULTS AND CONCLUSIONS: A) The European researchers Zülzer (Z Exp Path Ther 23:307-318, 1908) and Paulescu (CR Seances Soc Biol Fil 85:558, 1921) meet the requirements of the priority rule in the discovery of the antidiabetic hormone. B) Factors of socioeconomic and political nature related with the First World War and the inter-war period delayed the process of purification of the antidiabetic hormone in Europe. C) The Canadian scientist J. Collip, University of Alberta, temporarily assimilated to the University of Toronto, and the American chemist and researcher G. Walden, with the expert collaboration of Eli Lilly & Co., were the main authors of the purification process of the antidiabetic hormone. D) The scientific evidence, reflected in the heuristics of this research, allows to assert that the basic investigation carried out by the Department of Physiology of the University of Toronto, directed by the Scottish J. Macleod, in conjunction with the clinical research undertaken by the Department of Medicine of the University of Toronto (W. Campbell, A. Fletcher, D. Graham) made it possible in record time the successful treatment of patients with what was until then a deadly disease.


Assuntos
Diabetes Mellitus , Insulina , Humanos , História do Século XX , Insulina/uso terapêutico , Canadá , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/história , Hipoglicemiantes/uso terapêutico , Pâncreas , Glucagon
18.
Acta Diabetol ; 60(9): 1241-1256, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37266749

RESUMO

AIMS: To analyze the main contributions to the discovery of the antidiabetic hormone in the period between 1889, the year in which Oskar Minkowski demonstrated that complete pancreatectomy in dogs caused diabetes, and the year 1923, the date in which the clinical use of insulin was consolidated. A main objective has been to review the controversies that followed the Nobel Prize and to outline the role of the priority rule in Science. METHODS: We have considered the priority rule defined by Robert Merton in 1957, which takes into account the date of acceptance of the report of a discovery in an accredited scientific journal and/or the granting of a patent, complemented by the criteria set out by Ronald Vale and Anthony Hyman (2016) regarding the transfer of information to the scientific community and its validation by it. The awarding of the Nobel Prize in Physiology or Medicine in October 1923 has represented a frame of reference. The claims and disputes regarding the prioritization of the contributions of the main researchers in the organotherapy of diabetes have been analyzed through the study of their scientific production and the debate generated in academic institutions. MAIN RESULTS AND CONCLUSIONS: (1) According to the criteria of Merton, Vale and Hyman, the priority of the discovery of the antidiabetic hormone corresponds to the investigations developed in Europe by E. Gley (1900), GL Zülzer (1908) and NC Paulescu (1920). (2) The active principle of the pancreatic extracts developed by Zülzer (acomatol), Paulescu (pancreina) and Banting and Best (insulin) was the same. (3) JB Collip succeeded in isolating the active ingredient from the pancreatic extract in January 1922, eliminating impurities to the point of enabling its use in the clinic. (4) In 1972, the Nobel Foundation modified the purpose of the 1923 Physiology or Medicine award to Banting and Macleod by introducing a new wording: "the credit for having produced the pancreatic hormone in a practical available form" (instead of "for the discovery of insulin").


Assuntos
Diabetes Mellitus , Prêmio Nobel , Animais , Cães , História do Século XX , Insulina/uso terapêutico , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/história , Glucagon , Extratos Pancreáticos/uso terapêutico , Hipoglicemiantes/uso terapêutico
19.
Biofabrication ; 15(3)2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37236174

RESUMO

Biofilm-associated infections are causing over half a million deaths each year, raising the requirement for innovative therapeutic approaches. For developing novel therapeutics against bacterial biofilm infections, complexin vitromodels that allow to study drug effects on both pathogens and host cells as well as their interaction under controlled, physiologically relevant conditions appear as highly desirable. Nonetheless, building such models is quite challenging because (1) rapid bacterial growth and release of virulence factors may lead to premature host cell death and (2) maintaining the biofilm status under suitable co-culture requires a highly controlled environment. To approach that problem, we chose 3D bioprinting. However, printing living bacterial biofilms in defined shapes on human cell models, requires bioinks with very specific properties. Hence, this work aims to develop a 3D bioprinting biofilm method to build robustin vitroinfection models. Based on rheology, printability and bacterial growth, a bioink containing 3% gelatin and 1% alginate in Luria-Bertani-medium was found optimal forEscherichia coliMG1655 biofilms. Biofilm properties were maintained after printing, as shown visually via microscopy techniques as well as in antibiotic susceptibility assays. Metabolic profile analysis of bioprinted biofilms showed high similarity to native biofilms. After printing on human bronchial epithelial cells (Calu-3), the shape of printed biofilms was maintained even after dissolution of non-crosslinked bioink, while no cytotoxicity was observed over 24 h. Therefore, the approach presented here may provide a platform for building complexin vitroinfection models comprising bacterial biofilms and human host cells.


Assuntos
Bioimpressão , Humanos , Bioimpressão/métodos , Impressão Tridimensional , Hidrogéis , Biofilmes , Bactérias , Células Epiteliais , Alicerces Teciduais , Engenharia Tecidual/métodos
20.
Adv Drug Deliv Rev ; 183: 114141, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35149123

RESUMO

Mucus covers all wet epithelia and acts as a protective barrier. In the airways of the lungs, the viscoelastic mucus meshwork entraps and clears inhaled materials and efficiently removes them by mucociliary escalation. In addition to physical and chemical interaction mechanisms, the role of macromolecular glycoproteins (mucins) and antimicrobial constituents in innate immune defense are receiving increasing attention. Collectively, mucus displays a major barrier for inhaled aerosols, also including therapeutics. This review discusses the origin and composition of tracheobronchial mucus in relation to its (barrier) function, as well as some pathophysiological changes in the context of pulmonary diseases. Mucus models that contemplate key features such as elastic-dominant rheology, composition, filtering mechanisms and microbial interactions are critically reviewed in the context of health and disease considering different collection methods of native human pulmonary mucus. Finally, the prerequisites towards a standardization of mucus models in a regulatory context and their role in drug delivery research are addressed.


Assuntos
Pulmão , Muco , Sistemas de Liberação de Medicamentos , Humanos , Mucinas/análise , Mucinas/química , Muco/química , Reologia
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