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1.
J Med Virol ; 95(5): e28800, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37218583

RESUMO

Studies analyzing the relationship between BK polyomavirus (BKV) or JC polyomavirus (JCV) infection and kidney transplant (KT) long term clinical outcomes are scarce. Therefore, we evaluated this relationship in a single-center retrospective cohort of 288 KT patients followed for 45.4(27.5; 62.5) months. Detection of BKV viremia in two consecutive analyses led to discontinuation of antimetabolite and initiation of mammalian target of rapamycin inhibitor. Outcome data included de novo BKV and/or JCV viremia and/or viruria after KT, death-censored graft survival and patient survival. BKV viruria and viremia were detected in 42.4% and 22.2% of KT recipients, respectively. BKV viremic patients had higher urinary BKV viral loads at the onset of viruria, when compared to nonviremic patients (7 log10 vs. 4.9 log10 cp/mL, p < 0.001). JCV viruria was identified in 38.5% of KT patients; the 5.9% of KT recipients who developed JCV viremia had higher JCV urinary viral loads at the onset of viruria, when compared to non-viremic patients (5.3 vs. 3.7 log10 cp/mL, p = 0.034). No differences were found in estimated glomerular filtration rate at the end of follow up, when comparing BKV or JCV viruric or viremic patients with nonviremic patients. No association was found between JCV or BKV viruria or viremia and death/graft failure. Therefore, higher BKV urinary viral loads at the onset could serve as an early maker of over immunosuppression. JCV and BKV replication was not associated with inferior clinical outcomes in KT patients with the above-mentioned immunosuppression strategy.


Assuntos
Vírus BK , Vírus JC , Nefropatias , Transplante de Rim , Infecções por Polyomavirus , Infecções Tumorais por Vírus , Humanos , Transplante de Rim/efeitos adversos , Estudos Retrospectivos , Vírus BK/genética , Viremia , Vírus JC/genética , DNA Viral
2.
Eur J Pediatr ; 181(3): 1259-1262, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34595613

RESUMO

Cytomegalovirus (CMV) is the most frequent cause of congenital infection all over the world. Its prevalence ranges from 0.2 to 2.2%. Transmission from children to their pregnant mothers is a well-known risk factor, particularly if they attend a childcare centre. This study aims to compare the prevalence of CMV congenital infection (CMV_CI) in Portugal (Lisbon) between two studies, performed respectively in 2019 and 2020. In the 2019 study, performed in two hospitals, we found a 0.67% CMV_CI prevalence, using a pool strategy previously tested with saliva samples. In the 2020 study, using the same pool approach in four hospitals (the previous and two additional), and based on 1277 samples, the prevalence was 0.078%.Conclusion: The close temporal coincidence with COVID-19 lockdown suggests that these measures may have had a significant impact on this reduction, although other explanations cannot be ruled-out. What is Known: • Cytomegalovirus is the leading cause of congenital infection. • Behavioural measures decrease cytomegalovirus seroconversion in pregnant women. What is New: • From 2019 to 2020 there was a significant reduction in the prevalence of congenital CMV infection.


Assuntos
COVID-19 , Infecções por Citomegalovirus , Complicações Infecciosas na Gravidez , COVID-19/epidemiologia , COVID-19/prevenção & controle , Criança , Controle de Doenças Transmissíveis , Infecções por Citomegalovirus/congênito , Infecções por Citomegalovirus/epidemiologia , Infecções por Citomegalovirus/prevenção & controle , Feminino , Humanos , Portugal/epidemiologia , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/prevenção & controle , Prevalência , SARS-CoV-2
3.
Emerg Infect Dis ; 27(3): 880-893, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33622483

RESUMO

Staphylococcus saprophyticus is a primary cause of community-acquired urinary tract infections (UTIs) in young women. S. saprophyticus colonizes humans and animals but basic features of its molecular epidemiology are undetermined. We conducted a phylogenomic analysis of 321 S. saprophyticus isolates collected from human UTIs worldwide during 1997-2017 and 232 isolates from human UTIs and the pig-processing chain in a confined region during 2016-2017. We found epidemiologic and genomic evidence that the meat-production chain is a major source of S. saprophyticus causing human UTIs; human microbiota is another possible origin. Pathogenic S. saprophyticus belonged to 2 lineages with distinctive genetic features that are globally and locally disseminated. Pangenome-wide approaches identified a strong association between pathogenicity and antimicrobial resistance, phages, platelet binding proteins, and an increased recombination rate. Our study provides insight into the origin, transmission, and population structure of pathogenic S. saprophyticus and identifies putative new virulence factors.


Assuntos
Infecções Comunitárias Adquiridas , Infecções Estafilocócicas , Infecções Urinárias , Animais , Humanos , Staphylococcus saprophyticus , Suínos , Fatores de Virulência
4.
Antimicrob Agents Chemother ; 65(7): e0268520, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-33941519

RESUMO

Staphylococcus saprophyticus is a common pathogen of the urinary tract, a heavy metal-rich environment, but information regarding its heavy metal resistance is unknown. We investigated 422 S. saprophyticus isolates from human infection and colonization/contamination, animals, and environmental sources for resistance to copper, zinc, arsenic, and cadmium using the agar dilution method. To identify the genes associated with metal resistance and assess possible links to pathogenicity, we accessed the whole-genome sequence of all isolates and used in silico and pangenome-wide association approaches. The MIC values for copper and zinc were uniformly high (1,600 mg/liter). Genes encoding copper efflux pumps (copA, copB, copZ, mco, and csoR) and zinc transporters (zinT, czrAB, znuBC, and zur) were abundant in the population (20 to 100%). Arsenic and cadmium showed various susceptibility levels. Genes encoding the ars operon (arsRDABC), an ABC transporter and a two-component permease, were linked to resistance to arsenic (MICs ≥ 1,600 mg/liter; 14% [58/422]; P < 0.05). At least three cad genes (cadA or cadC and cadD-cadX or czrC) and genes encoding multidrug efflux pumps and hyperosmoregulation in acidified conditions were associated with resistance to cadmium (MICs ≥ 200 mg/liter; 20% [85/422]; P < 0.05). These resistance genes were frequently carried by mobile genetic elements. Resistance to arsenic and cadmium were linked to human infection and a clonal lineage originating in animals (P < 0.05). Altogether, S. saprophyticus was highly resistant to heavy metals and accumulated multiple metal resistance determinants. The highest arsenic and cadmium resistance levels were associated with infection, suggesting resistance to these metals is relevant for S. saprophyticus pathogenicity.


Assuntos
Arsênio , Metais Pesados , Animais , Cádmio , Cobre , Humanos , Testes de Sensibilidade Microbiana , Staphylococcus saprophyticus
5.
Br J Clin Pharmacol ; 87(8): 3227-3233, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33474776

RESUMO

AIMS: To compare the pharmacokinetics of amoxicillin (AMX) in obese and nonobese subjects, given as single dose 875-mg tablets. METHODS: A prospective, single-centre, open-label, clinical study was carried out involving 10 nonobese and 20 obese subjects given a dose of an AMX 875-mg tablet. Serial blood samples were collected between 0 and 8 hours after administration of AMX and plasma levels were quantified by liquid chromatography-tandem mass spectrometry. The pharmacokinetic parameters (PK) were calculated by noncompartmental analysis and means of the 2 groups were compared using Student t-test. Analysis of correlation between covariates and PK was performed using Pearson's correlation coefficient. RESULTS: Ten nonobese subjects (mean age 30.6 ± 7.12 y; body mass index 21.56 ± 1.95 kg/m2 ) and 20 obese subjects (mean age 34.47 ± 7.03 y; body mass index 33.17 ± 2.38 kg/m2 ) participated in the study. Both maximum concentration (Cmax ; 12.12 ± 4.06 vs. 9.66 ± 2.93 mg/L) and area under the curve (AUC)0-inf (34.18 ± 12.94 mg.h/L vs. 26.88 ± 9.24 mg.h/L) were slightly higher in nonobese than in obese subjects, respectively, but differences were not significant. The volume of distribution (V/F) parameter was statistically significantly higher in obese compared to nonobese patients (44.20 ± 17.85 L vs. 27.57 ± 12.96 L). Statistically significant correlations were observed for several weight metrics vs. AUC, Cmax , V/F and clearance, and for creatinine clearance vs. AUC, Cmax and clearance. CONCLUSION: In obese subjects, the main altered PK was V/F as a consequence of greater body weight. This may result in antibiotic treatment failure if standard therapeutic regimens are administered.


Assuntos
Amoxicilina , Obesidade , Administração Oral , Adulto , Área Sob a Curva , Cromatografia Líquida , Humanos , Estudos Prospectivos , Adulto Jovem
6.
Eur J Pediatr ; 180(4): 1067-1072, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33052471

RESUMO

Human cytomegalovirus (HCMV) is the leading congenital infection agent in the world. The importance of screening this infection has been debated, as 10-15% of the asymptomatic newborns with HCMV at birth will present late sequelae. The aim of this study was to test the feasibility of using saliva pools from newborns in a screening program for congenital HCMV infection, in two Portuguese hospitals. The screening was based on the use of pools of 10 saliva samples for detection of viral DNA by real-time PCR. Whenever there was a positive pool, the samples were tested individually, and for each positive sample the result was confirmed with a urine sample collected in the first 2 weeks of life. The study involved 1492 newborns. One hundred and fifty pools were screened, with 14 positive results in saliva, but only 10 were confirmed in urine samples, giving a prevalence of congenital HCMV infection in both hospitals of 0.67% (CI95% 0.36 to 1.23%).Conclusion: The overall prevalence of congenital HCMV infection in both hospitals was 0.67%. The use of saliva pools proved to be effective for the screening of this congenital infection, allowing timely screening and confirmation in a large population, with associated cost reduction. What is Known: • Newborn screening for HCMV is desirable. • Saliva is a good and practical sample. What is New: • The feasibility of using saliva pools for a large-scale screening. • The cost reduction of this strategy.


Assuntos
Infecções por Citomegalovirus , Citomegalovirus , Citomegalovirus/genética , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/epidemiologia , DNA Viral , Feminino , Humanos , Recém-Nascido , Triagem Neonatal , Reação em Cadeia da Polimerase em Tempo Real , Saliva
7.
Am J Transplant ; 20(4): 1188-1191, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31654479

RESUMO

Kidney transplant (KT) recipients have an increased risk for urothelial carcinoma. A role for JC virus (JCV) in human cancers is not yet proved but there is an increasingly reported association between BK virus (BKV) nephropathy and renourinary neoplasms. We report a KT recipient who developed a high-grade urothelial carcinoma 5 years after a diagnosis of JCV nephropathy and 9 years after kidney transplantation. Neoplastic tissue was positive for JCV DNA by real-time polymerase chain reaction (PCR). Immunochemical staining showed strong positivity for cell cycle markers (p16, p53, and Ki67) and for early viral protein JCV large T antigen (JCV LTag; using a broad polyomavirus antibody); however, late viral protein (VP1) stained negative. In contrast, in non-neoplastic urothelium, JCV DNA and all immunochemical markers were negative. These facts suggest that malignancy was induced by JCV. To the best of our knowledge, this is the first report of urothelial high-grade carcinoma associated with JCV nephropathy in a KT recipient.


Assuntos
Vírus BK , Carcinoma de Células de Transição , Vírus JC , Transplante de Rim , Infecções por Polyomavirus , Infecções Tumorais por Vírus , Neoplasias da Bexiga Urinária , Vírus BK/genética , DNA Viral/genética , Humanos , Vírus JC/genética , Transplante de Rim/efeitos adversos , Infecções por Polyomavirus/complicações , Retroviridae , Neoplasias da Bexiga Urinária/etiologia
8.
BMC Pulm Med ; 20(1): 39, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32054471

RESUMO

BACKGROUND: Respiratory virome is an integral part of the human microbiome and its characterization may contribute to a better understanding of the changes that arise in the disease and, consequently, influence the approach and treatment of patients with acute lower respiratory infections. The aim of this study was to evaluate the presence of respiratory viruses in the lower airways of individuals undergoing invasive mechanical ventilation, with and without acute lower respiratory infection (respectively WRI and WORI groups). METHODS: We studied 44 mini-bronchoalveolar lavage samples (collected with a double catheter, Combicath® kit) from patients with mean age in the seventh decade, 20 from WORI group and 24 from WRI group, who were hospitalized for acute respiratory failure in Intensive Care Units of two hospitals in the Lisbon area. Real-time PCR was applied to verify analyse the presence of 15 common respiratory viruses (adenovirus, human bocavirus, influenza virus A and B, repiratory syncytial virus, human parainfluenza virus types 1, 2, 3 and 4, human enterovirus, human rhinovirus, human metapneumovirus, human coronavirus group 1 (229E, NL63) and 2 (OC43, HKU1). RESULTS: Respiratory viruses were detected in six of the 20 patients in the WORI group: influenza AH3 (n = 2), parainfluenza virus 1/3 (n = 2), human rhinovirus (n = 2), respiratory syncytial virus (n = 1) and human metapneumovirus (n = 1). In the WRI group, respiratory viruses were detected in 12 of the 24 patients: influenza AH3 (n = 3), human rhinovirus (n = 3), respiratory syncytial virus (n = 3), human metapneumovirus (n = 3), human bocavirus (n = 2) and human enterovirus (n = 1). Simultaneous detection of two viruses was recorded in two samples in both groups. CONCLUSIONS: The results of this study suggest the presence of common respiratory viruses in the lower respiratory tract without causing symptomatic infection, even in carefully collected lower samples. This may have important implications on the interpretation of the results on the diagnostic setting.


Assuntos
Respiração Artificial , Insuficiência Respiratória/terapia , Insuficiência Respiratória/virologia , Infecções Respiratórias/complicações , Viroses/complicações , Viroses/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/terapia , Viroses/virologia , Adulto Jovem
9.
Int J Sports Med ; 41(1): 44-53, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31747700

RESUMO

The indirect identification of doping in sports can be performed by assessing athletes' hematological perturbations from the analysis of blood collected on different occasions. Because prosecution for doping based on this information requires expensive and time-consuming interpretation of blood analysis results by various expert hematologists, mathematical data screening is performed to decide which cases should be forwarded to hematologists. The current Bayesian and univariate screening of data does not process the multivariate trends of blood parameters or take the time interval between samplings into account. This work presents a computational tool that overcomes these limitations by calculating a single score, the hematological perturbation index (HPIx), for which a threshold is defined above which hematologists should be asked to assess the athlete's biological passport. The doping detection from this index, normalized for days difference between samplings based on 3, 4 or 5 consecutive samplings, is associated with true positive result rates (TP) not below 98% and false positive result rates (FP) less than 0.9%. Therefore, this tool can be useful as an early warning system of hematological perturbations to decide which athletes should be more closely monitored and which biological passports should be forwarded to hematologists for medical interpretation of data.


Assuntos
Dopagem Esportivo , Testes Hematológicos , Detecção do Abuso de Substâncias/métodos , Reações Falso-Positivas , Humanos , Método de Monte Carlo , Análise Multivariada , Incerteza
10.
Molecules ; 25(18)2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32947912

RESUMO

The antimicrobial evaluation of twelve natural and hemisynthetic isopimarane diterpenes are reported. The compounds were evaluated against a panel of Gram-positive bacteria, including two methicillin-resistant Staphylococcus aureus (MRSA) strains and one vancomycin-resistant Enterococcus (VRE) strain. Only natural compounds 7,15-isopimaradien-19-ol (1) and 19-acetoxy-7,15-isopimaradien-3ß-ol (6) showed promising results. Isopimarane (1) was the most active, showing MIC values between 6.76 µM against S. aureus (ATCC 43866) and 216.62 µM against E. faecalis (FFHB 427483) and E. flavescens (ATCC 49996). Compound (6) showed moderated activity against all tested microorganisms (MIC between value 22.54 and 45.07 µM). These compounds were found to be active against the methicillin-sensitive strains of S. aureus (CIP 106760 and FFHB 29593), showing MIC values of 13.55 (1) and 22.54 (6) µM. Both compounds were also active against vancomycin-resistant E. faecalis (ATCC 51299) (MIC values of 54.14 and 45.07 µM, respectively). In addition, the cytotoxicity of nine compounds 7,15-isopimaradien-3ß,19-diol (2); mixture: 15-isopimarene-8ß-isobutyryloxy-19-ol and 15-isopimarene-8ß-butyryloxy-19-ol (3); 3ß-acetoxy-7,15-isopimaradiene-19-ol (5); 19-acetoxy-7,15-isopimaradiene-3ß-ol (6); 3ß,19-diacetoxy-7,15-isopimaradiene (8); 15-isopimarene-8ß,19-diol (9); 19-O-ß-d-glucopyranoside-7,15-isopimaradiene (10); lagascatriol-16-O-ß-d-glucopyranoside (11) and lagascatriol-16-O-α-d-mannopyranoside (12) was evaluated in the human breast cancer cell line MDA-MB-231. Isopimarane (2) was the only compound showing some cytotoxicity. The IC50 value of compound (2) was 15 µM, suggesting a mild antiproliferative activity against these breast cancer cells.


Assuntos
Abietanos/química , Anti-Infecciosos/química , Diterpenos/química , Anti-Infecciosos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Diterpenos/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade , Resistência a Vancomicina/efeitos dos fármacos
11.
Mol Pharm ; 16(12): 5025-5034, 2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31721592

RESUMO

The potential of a physiologically-based pharmacokinetic (PBPK) model to predict oral amoxicillin bioavailability, by considering the physiological changes after "Roux-en-Y gastric bypass" (RYGB) surgery in bariatric patients, was evaluated. A middle-out approach for parameter estimations was undertaken using in vitro, in situ, and in vivo data. The observed versus predicted plasma concentrations and the model sensitivity of the simulated parameters of AUC0-inf and Cmax of amoxicillin (AMX) were used to confirm the reliability of the estimation. The model considers that a drug-transporter (Transp) in the initial segments of the normal intestine plays a significant role in the AMX absorption. A lower fraction absorbed (Fabs) was observed in RYGB patients (54.43% for suspension and 45.21% for tablets) compared to healthy subjects (77.48% capsule). Furthermore, the tablet formulation presented a lower dissolved fraction (Fd) and Fabs compared to the suspension formulation of AMX in RYGB patients (91.70% and 45.21% versus 99.92% and 54.43%, respectively). The AUC0-inf and Cmax were sensitive to changes in Rtintestine, PeffAMX, and Transp for both healthy and RYGB models. Additionally, AUC0-inf and Cmax were also sensitive to changes in the tlag parameter for tablet formulation in RYGB patients. The PBPK model showed a reduction in AMX bioavailability as a consequence of reduced intestinal length after RYGB surgery. Additionally, the difference in the predicted Fd and Fabs between suspension and tablet suggests that liquid formulations are preferable in postbariatric patients.


Assuntos
Amoxicilina/administração & dosagem , Amoxicilina/farmacocinética , Derivação Gástrica , Administração Oral , Humanos , Cinética , Solubilidade , Suspensões/química
12.
Br J Clin Pharmacol ; 85(9): 2118-2125, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31215676

RESUMO

AIMS: To evaluate the relative bioavailability of oral amoxicillin (AMX) tablets in comparison to AMX suspension in Roux-en-Y gastric bypass bariatric subjects. METHODS: A randomized, double-blind, cross-over study was performed on the bioavailability of oral AMX tablets and suspension in Roux-en-Y gastric bypass subjects operated at least 3 months previously . Doses of 875 mg of the AMX tablet or 800 mg of the AMX suspension were given to all the subjects, allowing a washout of 7 days between the periods. Blood samples were collected at 0, 0.25, 0.5, 1, 1.5, 2, 4, 6 and 8 hours after drug administration and the AMX levels were quantified by liquid chromatography coupled with triple quadrupole tandem mass spectrometry. The pharmacokinetic parameters were calculated by noncompartmental analysis, normalized to an 875 mg dose and the bioavailability of the AMX from the tablets was compared to that from the suspension formulation. RESULTS: Twenty subjects aged 42.65 ± 7.21 years and with a body mass index of 29.88 ± 4.36 kg/m2 were enrolled in the study. The maximum AMX plasma concentration of the tablets and the suspension (normalized to 875 mg) were 7.42 ± 2.99 mg/L and 8.73 ± 3.26 mg/L (90% confidence interval of 70.71-99.11), and the total area under the curve from time zero to infinity were 23.10 ± 7.41 mg.h/L and 27.59 ± 8.32 mg.h/L (90% confidence interval of 71.25-97.32), respectively. CONCLUSION: The tablets presented a lower bioavailability than the suspension formulation and the total absorbed amount of AMX in these subjects was lower in comparison to the standard AMX absorption rates in nonbariatric subjects, regardless of the formulation.


Assuntos
Amoxicilina/farmacocinética , Antibacterianos/farmacocinética , Derivação Gástrica/efeitos adversos , Administração Oral , Adulto , Amoxicilina/administração & dosagem , Amoxicilina/sangue , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Área Sob a Curva , Disponibilidade Biológica , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Suspensões , Comprimidos
13.
Mol Pharm ; 15(12): 5454-5467, 2018 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-30372084

RESUMO

The goal of this project was to explore and to statistically evaluate the responsible gastrointestinal (GI) factors that are significant factors in explaining the systemic exposure of ibuprofen, between and within human subjects. In a previous study, we determined the solution and total concentrations of ibuprofen as a function of time in aspirated GI fluids, after oral administration of an 800 mg IR tablet (reference standard) of ibuprofen to 20 healthy volunteers in fasted state conditions. In addition, we determined luminal pH and motility pressure recordings that were simultaneously monitored along the GI tract. Blood samples were taken to determine ibuprofen plasma levels. In this work, an in-depth statistical and pharmacokinetic analysis was performed to explain which underlying GI variables are determining the systemic concentrations of ibuprofen between (inter-) and within (intra-) subjects. In addition, the obtained plasma profiles were deconvoluted to link the fraction absorbed with the fraction dissolved. Multiple linear regressions were performed to explain and quantitatively express the impact of underlying GI physiology on systemic exposure of the drug (in terms of plasma Cmax/AUC and plasma Tmax). The exploratory analysis of the correlation between plasma Cmax/AUC and the time to the first phase III contractions postdose (TMMC-III) explains ∼40% of the variability in plasma Cmax for all fasted state subjects. We have experimentally shown that the in vivo intestinal dissolution of ibuprofen is dependent upon physiological variables like, in this case, pH and postdose phase III contractions. For the first time, this work presents a thorough statistical analysis explaining how the GI behavior of an ionized drug can explain the systemic exposure of the drug based on the individual profiles of participating subjects. This creates a scientifically based and rational framework that emphasizes the importance of including pH and motility in a predictive in vivo dissolution methodology to forecast the in vivo performance of a drug product. Moreover, as no extensive first-pass metabolism is considered for ibuprofen, this study demonstrates how intraluminal drug behavior is reflecting the systemic exposure of a drug.


Assuntos
Liberação Controlada de Fármacos , Jejum/fisiologia , Absorção Gastrointestinal/fisiologia , Trato Gastrointestinal/fisiologia , Ibuprofeno/farmacocinética , Administração Oral , Adulto , Área Sob a Curva , Disponibilidade Biológica , Variação Biológica Individual , Variação Biológica da População/fisiologia , Conjuntos de Dados como Assunto , Feminino , Voluntários Saudáveis , Humanos , Concentração de Íons de Hidrogênio , Ibuprofeno/administração & dosagem , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Solubilidade , Comprimidos , Adulto Jovem
14.
Mol Pharm ; 15(12): 5468-5478, 2018 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-30417648

RESUMO

Exploring the intraluminal behavior of an oral drug product in the human gastrointestinal (GI) tract remains challenging. Many in vivo techniques are available to investigate the impact of GI physiology on oral drug behavior in fasting state conditions. However, little is known about the intraluminal behavior of a drug in postprandial conditions. In a previous report, we described the mean solution and total concentrations of ibuprofen after oral administration of an immediate-release (IR) tablet in fed state conditions. In parallel, blood samples were taken to assess systemic concentrations. The purpose of this work was to statistically evaluate the impact of GI physiology (e.g., pH, contractile events) within and between individuals (intra and intersubject variability) for a total of 17 healthy subjects. In addition, a pharmacokinetic (PK) analysis was performed by noncompartmental analysis, and PK parameters were correlated with underlying physiological factors (pH, time to phase III contractions postdose) and study parameters (e.g., ingested amount of calories, coadministered water). Moreover, individual plasma profiles were deconvoluted to assess the fraction absorbed as a function of time, demonstrating the link between intraluminal and systemic behavior of the drug. The results demonstrated that the in vivo dissolution of ibuprofen depends on the present gastric pH and motility events at the time of administration. Both intraluminal factors were responsible for explaining 63% of plasma Cmax variability among all individuals. For the first time, an in-depth analysis was performed on a large data set derived from an aspiration/motility study, quantifying the impact of physiology on systemic behavior of an orally administered drug product in fed state conditions. The data obtained from this study will help us to develop an in vitro biorelevant dissolution approach and optimize in silico tools in order to predict the in vivo performance of orally administered drug products, especially in fed state conditions.


Assuntos
Liberação Controlada de Fármacos , Absorção Gástrica/fisiologia , Ibuprofeno/farmacocinética , Período Pós-Prandial/fisiologia , Estômago/fisiologia , Administração Oral , Adulto , Área Sob a Curva , Disponibilidade Biológica , Variação Biológica Individual , Variação Biológica da População/fisiologia , Simulação por Computador , Conjuntos de Dados como Assunto , Feminino , Interações Alimento-Droga/fisiologia , Esvaziamento Gástrico/fisiologia , Voluntários Saudáveis , Humanos , Concentração de Íons de Hidrogênio , Ibuprofeno/administração & dosagem , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Solubilidade , Comprimidos , Adulto Jovem
15.
Pharm Res ; 35(6): 111, 2018 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-29600438

RESUMO

PURPOSE: Mycobacterium tuberculosis which causes tuberculosis, is primarily resident within macrophages. 1,3-ß-glucan has been proposed as a ligand to target drug loaded nanoparticles (NPs) to macrophages. In this study we characterized the intracellular pharmacokinetics of the anti-tubercular drug rifampicin delivered by 1,3-ß-glucan functionalized PLGA NPs (Glu-PLGA). We hypothesized that Glu-PLGA NPs would be taken up at a faster rate than PLGA NPs, and consequently deliver higher amounts of rifampicin into the macrophages. METHODS: Carbodiimide chemistry was employed to conjugate 1,3-ß-glucan and rhodamine to PLGA. Rifampicin loaded PLGA and Glu-PLGA NPs as well as rhodamine functionalized PLGA and Glu-PLGA NPs were synthesized using an emulsion solvent evaporation technique. Intracellular pharmacokinetics of rifampicin and NPs were evaluated in THP-1 derived macrophages. A pharmacokinetic model was developed to describe uptake, and modelling was performed using ADAPT 5 software. RESULTS: The NPs increased the rate of uptake of rifampicin by a factor of 17 and 62 in case of PLGA and Glu-PLGA, respectively. Expulsion of NPs from the macrophages was also observed, which was 3 fold greater for Glu-PLGA NPs than for PLGA NPs. However, the ratio of uptake to expulsion was similar for both NPs. After 24 h, the amount of rifampicin delivered by the PLGA and Glu-PLGA NPs was similar. The NPs resulted in at least a 10-fold increase in the uptake of rifampicin. CONCLUSIONS: Functionalization of PLGA NPs with 1,3-ß-glucan resulted in faster uptake of rifampicin into macrophages. These NPs may be useful to achieve rapid intracellular eradication of Mycobacterium tuberculosis.


Assuntos
Antibióticos Antituberculose/farmacocinética , Macrófagos/metabolismo , Nanopartículas/química , Rifampina/farmacocinética , Tuberculose/tratamento farmacológico , Antibióticos Antituberculose/uso terapêutico , Técnicas de Cultura de Células/métodos , Linhagem Celular , Portadores de Fármacos , Composição de Medicamentos/métodos , Humanos , Modelos Biológicos , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Rifampina/uso terapêutico , Tuberculose/microbiologia , beta-Glucanas/química
16.
Mol Pharm ; 14(12): 4281-4294, 2017 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-28737409

RESUMO

In this study, we determined the pH and buffer capacity of human gastrointestinal (GI) fluids (aspirated from the stomach, duodenum, proximal jejunum, and mid/distal jejunum) as a function of time, from 37 healthy subjects after oral administration of an 800 mg immediate-release tablet of ibuprofen (reference listed drug; RLD) under typical prescribed bioequivalence (BE) study protocol conditions in both fasted and fed states (simulated by ingestion of a liquid meal). Simultaneously, motility was continuously monitored using water-perfused manometry. The time to appearance of phase III contractions (i.e., housekeeper wave) was monitored following administration of the ibuprofen tablet. Our results clearly demonstrated the dynamic change in pH as a function of time and, most significantly, the extremely low buffer capacity along the GI tract. The buffer capacity on average was 2.26 µmol/mL/ΔpH in fasted state (range: 0.26 and 6.32 µmol/mL/ΔpH) and 2.66 µmol/mL/ΔpH in fed state (range: 0.78 and 5.98 µmol/mL/ΔpH) throughout the entire upper GI tract (stomach, duodenum, and proximal and mid/distal jejunum). The implication of this very low buffer capacity of the human GI tract is profound for the oral delivery of both acidic and basic active pharmaceutical ingredients (APIs). An in vivo predictive dissolution method would require not only a bicarbonate buffer but also, more significantly, a low buffer capacity of dissolution media to reflect in vivo dissolution conditions.


Assuntos
Líquidos Corporais/química , Motilidade Gastrointestinal/fisiologia , Trato Gastrointestinal/fisiologia , Ibuprofeno/farmacocinética , Absorção Intestinal/fisiologia , Absorção Fisiológica , Administração Oral , Adulto , Líquidos Corporais/fisiologia , Soluções Tampão , Liberação Controlada de Fármacos , Voluntários Saudáveis , Humanos , Concentração de Íons de Hidrogênio , Mucosa Intestinal/fisiologia , Manometria , Pessoa de Meia-Idade , Solubilidade , Comprimidos , Equivalência Terapêutica , Fatores de Tempo , Adulto Jovem
17.
BMC Public Health ; 17(1): 146, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28143602

RESUMO

BACKGROUND: Rubella infection can affect several organs and cause birth defects that are responsible for congenital rubella syndrome (CRS). Congenital hearing loss is the most common symptom of this syndrome, occurring in approximately 60% of CRS cases. Worldwide, over 100 000 babies are born with CRS every year. There is no specific treatment for rubella, but the disease is preventable by vaccination. Since 1969, the rubella vaccine has been implemented in many countries, but in Africa, only a few countries routinely immunize against rubella. The aim of this study was to estimate the rate of infection from the wild-type rubella virus in São Tomé and Príncipe by determining rubella seroprevalence with a DBS method. The goal of this study was to reinforce the need for implementation of the rubella vaccine in this country. As secondary objectives, the validation of a DBS method was first attempted and an association between seroprevalence and hearing loss was assessed. METHODS: We collected samples from individuals observed during humanitarian missions in São Tomé and Príncipe. All individuals underwent an audiometric evaluation, and a drop of blood was collected for the dried blood spot (DBS). We define two groups: the case group (individuals with unilateral or bilateral hearing loss (HL)) and the control group (individuals with two normal ears). Patients were excluded if they suffered from conductive HL, if they showed evidence of possible causes of HL, if they had developmental delay or if they refused to participate in the study. RESULTS: Among the 315 subjects, we found 64.1% individuals with IgG for the rubella virus, 32.1% without immunity for the rubella virus and 3.8% who were borderline. In the control group, 62.6% were positive for the rubella IgG, whereas in the case group, 72% were positive. Analyzing both groups, with ages ranging from 2 to 14 years of age and from 15 to 35 years of age, we found a seroprevalence of 50.3% to rubella in the younger group and 82.1% in the older group, with a significant difference between cases and control group noted within the younger patients (p = 0.025). CONCLUSIONS: Rubella is a disease that can be prevented. Rubella infections are still very common in São Tomé and Príncipe, and women of child-bearing age are still at risk for rubella infection during pregnancy, justifying the urgency of vaccination against rubella. A statistically significant association between the group of children under 14 years of age with HL and immunity for rubella was observed in this country, although this study did not allow us to establish a cause-effect relationship between rubella infection and SNHL.


Assuntos
Perda Auditiva Neurossensorial/epidemiologia , Rubéola (Sarampo Alemão)/epidemiologia , Adolescente , Adulto , África Subsaariana/epidemiologia , Estudos de Casos e Controles , Criança , Serviços de Saúde da Criança , Pré-Escolar , Feminino , Perda Auditiva Neurossensorial/prevenção & controle , Humanos , Masculino , Missões Médicas , Rubéola (Sarampo Alemão)/sangue , Rubéola (Sarampo Alemão)/prevenção & controle , Vacina contra Rubéola/administração & dosagem , Estudos Soroepidemiológicos , Vacinação , Adulto Jovem
18.
Pharm Res ; 31(12): 3313-22, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24867425

RESUMO

PURPOSE: To develop a QSAR model, based on calculated molecular descriptors and an Artificial Neural Networks Ensemble (ANNE), for the estimation of rat tissue-to-blood partition coefficients (Kt:b), as well as the assessment of the applicability domain of the model and its utility in predicting the drug distribution in humans. METHODS: A total of 1460 individual Kt:b values (75% train and 25% validation), obtained in 13 different rat tissues were collected in the literature. A correlation between simple molecular descriptors for lipophilicity, ionization, size and hydrogen bonding capacity and Kt:b data was attempted by using an ANNE. RESULTS: Similar statistics were observed between the train and validation group of data with correlations, between the observed values and the predicted average ANNE values, of 0.909 and 0.896, respectively. A degradation of the correlations was observed for predicted values with high uncertainty, as judged by the standard deviations of the ANNE outputs. This was further observed when using the ANNE Kt:b values in a Physiologically based pharmacokinetic (PBPK) model for predicting the Human Volume of distribution of another 532 drugs. CONCLUSIONS: This model (available as a MS Excel® workbook in the Supporting material of this article) may be a valuable tool for prediction and simulation in early drug development, allowing the in silico estimation of rat Kt:b values for PBPK purposes and also indicating its applicability domain.


Assuntos
Redes Neurais de Computação , Preparações Farmacêuticas/metabolismo , Farmacocinética , Algoritmos , Animais , Simulação por Computador , Humanos , Modelos Biológicos , Relação Quantitativa Estrutura-Atividade , Ratos , Reprodutibilidade dos Testes , Distribuição Tecidual
19.
Eur J Pediatr ; 173(8): 1059-65, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24599798

RESUMO

UNLABELLED: Influenza surveillance is usually based on nationally organized sentinel networks of physicians and on hospital reports. This study aimed to test a different report system, based on parents' phone contact to the research team and in home collection of samples by a dedicated team. The identification of influenza and other respiratory viruses in children who attended a Hospital Emergency Department was also recorded. Real-time PCR and reverse transcription PCR were performed for influenza A and B, parainfluenza 1-4, adenovirus, human metapneumovirus, respiratory syncytial virus A and B, rhinovirus, enterovirus, group 1 coronaviruses, group 2 coronaviruses, and human bocavirus. One hundred children were included, 64 from the day care centers and 36 from the Hospital. Overall, 79 samples were positive for at least one respiratory virus. Influenza A (H3) was the virus most frequently detected: 25 cases, 20 of these in children under 5 years of age (ten from day care centers and ten who went to the hospital) which was higher than those reported by the National Influenza Surveillance Programme for this age. CONCLUSION: The results obtained in this study suggest that a surveillance system based on parents' reports could complement the implanted system of the National Influenza Surveillance Programme.


Assuntos
Monitoramento Epidemiológico , Influenza Humana/epidemiologia , Infecções Respiratórias/epidemiologia , Criança , Pré-Escolar , Serviço Hospitalar de Emergência , Feminino , Humanos , Lactente , Influenza Humana/virologia , Masculino , Pais , Portugal/epidemiologia , Reação em Cadeia da Polimerase em Tempo Real , Infecções Respiratórias/virologia , Vírus/isolamento & purificação
20.
Pharmaceutics ; 16(5)2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38794260

RESUMO

In the European Union, bioequivalence (BE) for narrow therapeutic index (NTI) drugs is currently demonstrated when the 90% confidence interval for the ratio of the population geometric means of the test and reference products for AUC, and in some cases for Cmax, falls within the acceptance range of 90.00% to 111.11%. However, meeting this requirement results in an increased difficulty of demonstrating BE and a need for clinical trials with larger subject sample sizes, especially for medium-to-high variability drugs. To address this challenge, a scaled average BE based on the reference product within-subject variability for narrowing the acceptance range of NTI drugs was recently proposed. However, this approach showed increased type I error (T1E), especially close to the cut-off point between the unscaled and scaled portions of the method. Based on simulations, this limitation can be overcome by predefining the protocol the path to be followed: either the fixed 90.00-111.11% acceptance range approach or the previously proposed scaled average BE approach with a slight adjustment of the one-sided significance level α to 0.042 for a 2 × 3 × 3 partial replicate design and without a lower cut-off point. This results in a mixed approach allowing to reduce the sample size whilst not inflating the T1E.

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