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1.
Front Pharmacol ; 15: 1331637, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38444938

RESUMO

Background: Ivacaftor is a modern drug used in the treatment of cystic fibrosis. It is highly lipophilic and exhibits a strong positive food effect. These characteristics can be potentially connected to a pronounced lymphatic transport after oral administration. Methods: A series of studies was conducted to describe the basic pharmacokinetic parameters of ivacaftor in jugular vein cannulated rats when dosed in two distinct formulations: an aqueous suspension and an oil solution. Additionally, an anesthetized mesenteric lymph duct cannulated rat model was studied to precisely assess the extent of lymphatic transport. Results: Mean ± SD ivacaftor oral bioavailability was 18.4 ± 3.2% and 16.2 ± 7.8%, respectively, when administered as an aqueous suspension and an oil solution. The relative contribution of the lymphatic transport to the overall bioavailability was 5.91 ± 1.61% and 4.35 ± 1.84%, respectively. Conclusion: Lymphatic transport plays only a minor role in the process of ivacaftor intestinal absorption, and other factors are, therefore, responsible for its pronounced positive food effect.

2.
J Thorac Cardiovasc Surg ; 165(2): 526-531.e1, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35469599

RESUMO

OBJECTIVE: The decision to perform a single-lung transplant (SLT) when the contralateral donor lung is rejected is a challenging scenario. The introduction of ex vivo lung perfusion (EVLP) has improved donor lung assessment, and we hypothesize that it has improved SLT outcomes in this setting. METHODS: A retrospective single-center review of all SLTs performed between 2000 and 2017 was performed in which the years 2000 to 2008 were considered the "pre-EVLP era" and 2009 to 2017 the "EVLP era." Recipients of SLT lungs when the contralateral lung was declined were classified into 3 groups: (1) Pre-EVLP era, (2a) EVLP era but EVLP not used, and (2b) EVLP era and EVLP used. The outcomes of interest were survival, time-to-extubation, and intensive care unit and hospital stay. RESULTS: Among 1692 transplants between 2000 and 2017, 244 (14%) were SLT. SLT rate was similar between eras (pre-EVLP 16% vs EVLP 15%), but more SLTs were performed where the contralateral lung was declined in the EVLP era (pre-EVLP 32% vs EVLP 45%, P = .04). Lungs evaluated on EVLP had lower procurement partial pressure of oxygen and were more often from donation after cardiac death donors. Recipients were generally also sicker, with a greater proportion of rapidly deteriorating recipients. Despite this, outcomes were similar between eras with a trend towards lower 30-day mortality in the EVLP era. CONCLUSIONS: The availability of EVLP allowed for better evaluation of marginal single lungs when the contralateral was declined. This has led to increased use rates with preserved outcomes despite use of more extended criteria organs.


Assuntos
Transplante de Pulmão , Pulmão , Humanos , Estudos Retrospectivos , Perfusão/efeitos adversos , Pulmão/cirurgia , Transplante de Pulmão/efeitos adversos , Doadores de Tecidos
3.
Artigo em Inglês | MEDLINE | ID: mdl-36342775

RESUMO

Introduction: Rheumatoid arthritis (RA) is a chronic autoimmune disease with unknown cause. It mainly affects joints and, without proper treatment, negatively impacts their movement, causes painful deformities, and reduces the patients' quality of life. Current treatment options consist of various types of disease-modifying antirheumatic drugs (DMARDs), however 20-30% of patients are partially resistant to them. Therefore, development of new drugs is necessary. Possible option are compounds exhibiting their action via endocannabinoid system, which plays an important role in pain and inflammation modulation. One such compound - cannabidiol (CBD) has already been shown to attenuate synovitis in animal model of RA in in vivo studies. However, it has low bioavailability due to its low water solubility and lipophilicity. This issue can be addressed by preparation of a lipid containing formulation targeting lymphatic system, another route of absorption in the body. Materials and Methods: CBD-containing emulsion was prepared by high-shear homogenization and its droplet size distribution was analysed by optical microscopy. The relative oral bioavailability compared to oil solution as well as total availability of CBD were assessed in a cross-over study in rats and absorption of CBD via lymphatic system was observed. The effect of CBD on the animal model of RA was determined. Results: Compared to oil solution, the emulsion exhibited higher absolute oral bioavailability. Significant lymphatic transport of CBD was observed in all formulations and the concentrations in lymph were calculated. The therapeutic effect of CBD on RA was confirmed as an improvement in clinical symptoms as well as morphological signs of disease activity were observed during the study. Conclusion: In this work, we prepared a simple stable emulsion formulation, determined the pharmacokinetic parameters of CBD and calculated its absolute bioavailability in rats. Moreover, we successfully tested the pharmaceutical application of such a formulation and demonstrated the positive effect of CBD in an animal model of RA.

4.
Pharmaceutics ; 14(2)2022 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-35214140

RESUMO

The aim of this prospective study was to evaluate the pharmacokinetics of ganciclovir in lung transplant recipients, to explore its covariates, and to propose an individualized dosing regimen. Ganciclovir was administered according to the protocol in a standardized intravenous dose of 5 mg/kg twice daily. Serum ganciclovir concentrations were monitored as a trough and at 3 and 5 h after dosing. Individual ganciclovir pharmacokinetic parameters were calculated in a two-compartmental pharmacokinetic model, while regression models were used to explore the covariates. Optimal loading and maintenance doses were calculated for each patient. In lung transplant recipients (n = 40), the median (IQR) ganciclovir total volume of distribution and clearance values were 0.65 (0.52-0.73) L/kg and 0.088 (0.059-0.118) L/h/kg, respectively. We observed medium-to-high inter-individual but negligible intra-individual variability in ganciclovir pharmacokinetics. The volume of distribution of ganciclovir was best predicted by height, while clearance was predicted by glomerular filtration rate. Bodyweight-normalized clearance was significantly higher in patients with cystic fibrosis, while distribution half-life was reduced in this subgroup. On the basis of the observed relationships, practical nomograms for individualized ganciclovir dosing were proposed. The dosing of ganciclovir in patients with cystic fibrosis requires special caution, as their daily maintenance dose should be increased by approximately 50%.

5.
Br J Pharmacol ; 178(23): 4663-4674, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34365639

RESUMO

BACKGROUND AND PURPOSE: Lymphatic transport of drugs after oral administration is an important mechanism for absorption of highly lipophilic compounds. Direct measurement in lymph duct cannulated animals is the gold standard method, but non-invasive cycloheximide chylomicron flow blocking method has gained popularity recently. However, concerns about its reliability have been raised. The aim of this work was to investigate the validity of cycloheximide chylomicron flow blocking method for the evaluation of lymphatic transport using model compounds with high to very high lipophilicity, that is, abiraterone and cinacalcet. EXPERIMENTAL APPROACH: Series of pharmacokinetic studies were conducted with abiraterone acetate and cinacalcet hydrochloride after enteral/intravenous administration to intact, lymph duct cannulated and/or cycloheximide pre-treated rats. KEY RESULTS: Mean total absolute oral bioavailability of abiraterone and cinacalcet was 7.0% and 28.7%, respectively. There was a large and significant overestimation of the lymphatic transport extent by the cycloheximide method. Mean relative lymphatic bioavailability of abiraterone and cinacalcet in cycloheximide method was 28-fold and 3-fold higher than in cannulation method, respectively. CONCLUSION AND IMPLICATIONS: Cycloheximide chylomicron flow blocking method did not provide reliable results on lymphatic absorption and substantially overestimated lymphatic transport for both molecules, that is, abiraterone and cinacalcet. This non-invasive method should not be used for the assessment of lymphatic transport and previously obtained data should be critically revised.


Assuntos
Quilomícrons , Absorção Intestinal , Administração Oral , Animais , Disponibilidade Biológica , Transporte Biológico , Quilomícrons/metabolismo , Cicloeximida/farmacologia , Preparações Farmacêuticas , Ratos , Reprodutibilidade dos Testes
6.
J Thorac Cardiovasc Surg ; 161(5): 1674-1685, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32723591

RESUMO

OBJECTIVES: Lobar lung transplantation (LLTx) from deceased donors is a potential solution for donor-recipient size mismatch for small sized recipients. We reviewed our institutional experience to compare outcomes after LLTx to standard lung transplantation (LTx). METHODS: We retrospectively reviewed transplants in our institution from January 2000 to December 2017. LLTx early- and long-term outcomes were compared with LTx. Additional analysis of outcomes was performed after dividing the cohort into 2 eras (era 1, 2000-2012; era 2, 2013-2017). RESULTS: Among the entire cohort (1665), 75 were LLTx (4.5%). Compared with LTx, LLTx were more frequently bridged to transplant with extracorporeal life support or mechanical ventilation and were transplanted in a rapidly deteriorating status (respectively, 20% vs 4.4%, P = .001; 22.7% vs 7.9, P < .001; and 41.3% vs 26.5%, P = .013). LLTx had longer intensive care unit and hospital lengths of stay (respectively, median 17 vs 4 days, and 45 vs 23, both P < .001), and greater 30-day mortality (13.3% vs 4.3%, P = .001) and 90-day mortality (17.3% vs 7.2%, P = .003). In era 2, despite a significantly greater 30-day mortality (10.8% vs 2.8%, P = .026), there was no significant difference in 90-day mortality between LLTx and LTx (13.5% vs 5.1%, P = .070). Overall survival at 1, 3, and 5 years was not significantly different between LLTx and LTx (73.2% vs 84.4%, 56.9% vs 68.4% and 50.4% vs 55.8, P = .088). CONCLUSIONS: Although LLTx is a high-risk procedure, both mid- and long-term survival are comparable with LTx in all cohorts in the modern era. LLTx therefore represents a valuable surgical option for small-sized recipients.


Assuntos
Transplante de Pulmão , Doadores de Tecidos , Adulto , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Pulmão/cirurgia , Transplante de Pulmão/efeitos adversos , Transplante de Pulmão/métodos , Transplante de Pulmão/mortalidade , Transplante de Pulmão/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
7.
Diagn Pathol ; 15(1): 132, 2020 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-33100226

RESUMO

BACKGROUND: Spitzoid melanocytic lesions represent a heterogeneous group of proliferations with ambiguous and overlapping terminology. The exact distinction of a Spitz nevus from a Spitzoid melanoma can be very difficult or, in some cases, impossible. Among the Spitzoid lesions, there is a lesion termed an atypical Spitz tumour (AST) that has intermediate histopathologic features between those of a Spitz nevus and a Spitzoid melanoma and thus uncertain malignant potential. There are several rare cases of patients with a Spitzoid melanoma initially misdiagnosed as a Spitz nevus or an AST with fatal consequences. It is, therefore, advised to perform a molecular characterization in cases where uncertain skin lesions are presented, as it may provide extended set of information with a possible impact on the treatment options. Furthermore, preventive measures, such as regular physical and skin examinations, as well as thorough scheduling of individual follow-up visits, are essential in patients with potentially malignant skin nevi. CASE REPORT: We report a case of a young adult female with a history of AST excision with a negative sentinel lymph node biopsy (SLNB) and insufficient follow-up. Four years after the primary dermatological diagnosis, she presented with a giant tumour in the right hemithorax. Radical en bloc resection of the tumour with right pneumonectomy and resection of the pericardium with reconstruction of the pericardium using mesh was performed. A definitive histopathological examination revealed a metastatic melanoma. The association of the previously diagnosed AST and subsequent appearance of melanoma metastases led to a retrospective re-evaluation of the initial lesion. The suspected diagnosis of Spitzoid melanoma, however, was not confirmed. Moreover, the molecular examination revealed a major discordance between the initial lesion and the lung tumour, which most likely excluded the possible association of the lung metastasis with the initial skin lesion. The initial skin lesion was a BRAF-mutant melanoma with Spitzoid features and termed as AST, while the giant lung metastasis was NRAS-mutant melanoma. The subsequent postoperative course was complicated by the appearance of brain metastases that were stereotactically irradiated. Nevertheless, despite complex specialised medical care, the patient's clinical condition rapidly deteriorated. By this time, no active oncological treatment was possible. The patient was delegated to local hospice for palliative care six months after the surgery and died three weeks later. CONCLUSIONS: Our patient was surgically treated at the age of 20 for AST and died four years later of metastatic NRAS-mutant melanoma most likely of different occult origin. Molecular characterization, as well as the close clinical follow-up should be always precisely performed in patients with uncertain skin lesions, such as AST.


Assuntos
Neoplasias Pulmonares/secundário , Melanoma/secundário , Neoplasias Primárias Múltiplas/genética , Nevo de Células Epitelioides e Fusiformes/patologia , Neoplasias Cutâneas/patologia , Feminino , GTP Fosfo-Hidrolases/genética , Humanos , Melanoma/genética , Proteínas de Membrana/genética , Mutação , Neoplasias Primárias Múltiplas/patologia , Nevo de Células Epitelioides e Fusiformes/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/secundário , Adulto Jovem , Melanoma Maligno Cutâneo
8.
J Thorac Oncol ; 12(2): 249-257, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27793776

RESUMO

INTRODUCTION: Lung cancer is the leading cause of cancer mortality worldwide; therefore, understanding the biological or clinical role of tumor-associated antigens and autoantibodies is of eminent interest for designing antitumor immunotherapeutic strategies. METHODS: Here we prospectively analyzed the serum frequencies of New York esophageal squamous cell carcinoma 1 (NY-ESO-1), human epidermal growth factor 2/neu, and melanoma-associated antigen A4 (MAGE-A4) antibodies and expression of the corresponding antigens in tumors of 121 patients with NSCLC undergoing an operation without prior neoadjuvant chemotherapy and compared them with those in 57 control age-matched patients with no history of a malignant disease. RESULTS: We found that only antibodies specific for NY-ESO-1 (19.8% [n = 24 of 121]) were significantly increased in the group of patients with NSCLC compared with in the controls. NY-ESO-1 seropositivity was significantly positively associated with an active smoking history in patients with NSCLC but not in smokers from the control group. In tumors, the frequency of NY-ESO-1 mRNA expression was 6.3% (in four of 64 patients), the frequency of human epidermal growth factor 2/neu (HER 2/neu) expression was 11.9% (five of 42), and the frequency of MAGE-A4 expression was 35.1% (20 of 57). MAGE-A4 expression in tumors correlated with smoking status and male sex in patients with NSCLC. Patients with squamous cell carcinoma displayed higher expression of NY-ESO-1 and MAGE-A4 in tumors than did patients with adenocarcinoma. On the other hand, 94.7% of nonsmoking patients in our study had adenocarcinoma (of whom 73.7% were women). CONCLUSION: These results confirm the reported high immunogenicity of NY-ESO-1 and suggest that a smoking-induced chronic inflammatory state might potentiate the development of NY-ESO-1-specific immune responses. Moreover, smoking might contribute to the expression of other cancer/testis antigens such as MAGE-A4 at early stages of NSCLC development.


Assuntos
Antígenos de Neoplasias/sangue , Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Neoplasias Pulmonares/sangue , Proteínas de Membrana/sangue , Proteínas de Neoplasias/sangue , Receptor ErbB-2/sangue , Fumar/efeitos adversos , Adenocarcinoma/sangue , Adenocarcinoma/etiologia , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias/imunologia , Carcinoma Pulmonar de Células não Pequenas/etiologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/patologia , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/patologia , Masculino , Proteínas de Membrana/imunologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos
9.
Cesk Patol ; 51(4): 175-80, 2015.
Artigo em Tcheco | MEDLINE | ID: mdl-26585108

RESUMO

Lung transplantation has become a standard therapeutic procedure for patients with end-stage pulmonary diseases in the Czech Republic. There were 246 lung transplantations performed from December 1997 to the end of November 2014 at the 3rd Department of Surgery, 1st Faculty of Medicine, Charles University in Prague and Motol University Hospital. The most common indications for transplantation were chronic obstructive pulmonary disease in 39.4 % of patients, idiopathic pulmonary fibrosis in 28.9 % of patients and cystic fibrosis in 19.1 % of patients. The trans-bronchial biopsy is important for monitoring patients after lung transplantation. The biopsy helps to detect acute cellular rejection, which was found within 63 % of our patients. Patients with the mild and moderate grade of acute cellular rejection got better after the anti-rejection therapy. The severe rejection in three patients led to the shock change in lung and to respiratory failure. Humoral rejection cannot be determined based on biopsy only - the capillaritis and the linear binding of C4d fraction of the complement to the capillaries are inconsistent findings and are not pathognomonic. The classification of chronic rejection, which corresponds to the bronchiolitis obliterans, is limited for the common absence of bronchioli in the biopsy. Therefore, bronchiolitis obliterans in our study group was detected in only 3.7 % of patients.Since the first transplantation, 109 of our patients have survived (44.3 %). After transplantation about 90 % of patients live one year, about 70.9 % of patients live 3 years and 69.1 % live 5 years. An autopsy at our department was performed in 79 cases. The most common causes of death were mycotic infections (aspergillosis, candidiasis), bacterial infections (Klebsiela, Pseudomonas aeruginosa, Burkholderia cepacia) followed by sepsis and viral infection (CMV, varicella zoster). At the autopsy, chronic rejection was found in 13 patients and it led to chronic respiratory failure, which was often complicated by an infection. The tumors as the cause of death were mostly generalized carcinomas.


Assuntos
Pneumopatias/cirurgia , Transplante de Pulmão/estatística & dados numéricos , Biópsia , República Tcheca/epidemiologia , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/epidemiologia , Humanos , Pulmão/patologia , Transplante de Pulmão/mortalidade
10.
Eur J Cardiothorac Surg ; 40(3): 619-24, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21334911

RESUMO

OBJECTIVE: To evaluate the safety and effectiveness of novel biodegradable (BD) stents to treat bronchial anastomotic stenosis in patients after lung transplantation. METHODS: Twenty BD stents were implanted endoscopically in six patients (median age 41.5 years (range 35-57 years)) with post-transplant bronchial anastomotic stenoses, between 2006 and 2010. All stents were custom-made from bio-absorbable polydioxanone (PDS). The median stent diameter was 12 mm (8-17 mm) and median length was 20mm (12-30 mm). All patients were evaluated clinically, by bronchoscopy and high-definition computed tomography (CT). RESULTS: The stenosis was initially relieved in all cases. There was no bleeding, perforation or displacement after BD stent implantation. Four patients needed multiple stenting for anastomotic re-stenosis. Median time to any re-stenting was 5 months (2-15 months). There was one sudden death, 1 year after the last BD stent implantation, from a pulmonary embolus. All five survivors are in good clinical condition up to 4 years' follow-up (median 40 months, range 7-48 months) since first stenting and intervention-free up to 44 months (median 24 months, range 7-44 months). CONCLUSIONS: This small pilot study shows that BD stents are a safe, effective and reliable alternative to classical metallic stents in patients with anastomotic stenosis after lung transplantation, and may avoid the need for permanent stenting.


Assuntos
Implantes Absorvíveis , Broncopatias/cirurgia , Transplante de Pulmão/efeitos adversos , Stents , Adulto , Obstrução das Vias Respiratórias/etiologia , Obstrução das Vias Respiratórias/cirurgia , Anastomose Cirúrgica/efeitos adversos , Broncopatias/etiologia , Broncoscopia , Constrição Patológica/etiologia , Constrição Patológica/cirurgia , Métodos Epidemiológicos , Humanos , Pessoa de Meia-Idade , Polidioxanona , Desenho de Prótese , Resultado do Tratamento
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