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1.
Talanta ; 226: 122045, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33676640

RESUMO

Hypoxia is a common medical problem, sometimes difficult to detect and caused by different situations. Control of hypoxia is of great medical importance and early detection is essential to prevent life threatening complications. However, the few current methods are invasive, expensive, and risky. Thus, the development of reliable and accurate sensors for the continuous monitoring of hypoxia is of vital importance for clinical monitoring. Herein, we report an implantable sensor to address these needs. The developed device is a low-cost, miniaturised implantable electrochemical sensor for monitoring hypoxia in tissue by means of pH detection. This technology is based on protonation/deprotonation of polypyrrole conductive polymer. The sensor was optimized in vitro and tested in vivo intramuscularly and ex vivo in blood in adult rabbits with respiration-induced hypoxia and correlated with the standard device ePOCTM. The sensor demonstrated excellent sensitivity and reproducibility; 46.4 ± 0.4 mV/pH in the pH range of 4-9 and the selectivity coefficient exhibited low interference activity in vitro. The device was linear (R2 = 0.925) with a low dispersion of the values (n = 11) with a cut-off of 7.1 for hypoxia in vivo and ex vivo. Statistics with one-way ANOVA (α = 0.05), shows statistical differences between hypoxia and normoxia states and the good performance of the pH sensor, which demonstrated good agreement with the standard device. The sensor was stable and functional after 18 months. The excellent results demonstrated the feasibility of the sensors in real-time monitoring of intramuscular tissue and blood for medical applications.


Assuntos
Acidose , Polímeros , Animais , Hipóxia/diagnóstico , Pirróis , Coelhos , Reprodutibilidade dos Testes
2.
Prenat Diagn ; 33(4): 384-90, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23494871

RESUMO

OBJECTIVE: This study aimed to evaluate the application of two quality assurance methods to the ductus venosus pulsatility index (DVPI), as a first-trimester aneuploidy marker, including retrospective assessment of distribution parameters and cumulative sum (CUSUM) plots. METHODS: The DVPI was measured in 14 444 singleton fetuses at 11+0 to 13+6 weeks in two Fetal Medicine centers during a 4-year period. Sonologist-specific quality assurance distribution parameters, previously described for nuchal translucency, were assessed: the median multiples of the median (MoM), the logarithmic standard deviation of DVPI MoMs and the weekly DVPI percent decrease. Quality assurance results were compared between median MoMs and MoM-based CUSUM plots. RESULTS: When sonologist-specific DVPI distribution parameters were retrospectively applied for quality assurance, a 1.0 median MoM, a 0.1 median logarithmic standard deviation and a 3.4 median weekly DVPI drop percentage were observed. CUSUM plots showed good agreement with 0.9-1.1 MoMs range for median MoM, in the assessment of sonologist-specific performances. CONCLUSION: Retrospective and prospective DVPI quality assurance methods appear to be applicable to DVPI at 11+0 to 13+6 weeks. Its use should be encouraged if DVPI is to be added to first-trimester Down syndrome or cardiac defects screening.


Assuntos
Aneuploidia , Transtornos Cromossômicos/diagnóstico por imagem , Feto/fisiologia , Ultrassonografia Pré-Natal/normas , Feminino , Feto/irrigação sanguínea , Humanos , Programas de Rastreamento , Gravidez , Primeiro Trimestre da Gravidez , Fluxo Pulsátil , Garantia da Qualidade dos Cuidados de Saúde , Estudos Retrospectivos
3.
Fetal Diagn Ther ; 27(3): 174-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20224253

RESUMO

Prostaglandin E(1) analogues, gemeprost and misoprostol, are the most widely used drugs for medical termination of pregnancy within the first two trimesters of pregnancy. Gemeprost has been reported to be associated with acute cardiovascular accidents in a few cases, but no adverse cardiovascular events have been reported with misoprostol. For this reason, misoprostol has been considered a potentially safer drug and is widely recommended as a first-choice drug in combination with mifepristone. We report a case of a 32-year-old woman with active smoking and obesity, who developed an episode of transient acute coronary artery vasospasm following the administration of intravaginal misoprostol. This report illustrates that misoprostol can also be associated with acute coronary events, although it remains to be evaluated whether the risk is similar or lower to gemeprost.


Assuntos
Abortivos não Esteroides/efeitos adversos , Aborto Induzido/efeitos adversos , Vasoespasmo Coronário/diagnóstico , Vasos Coronários/efeitos dos fármacos , Misoprostol/efeitos adversos , Abortivos não Esteroides/administração & dosagem , Adulto , Alprostadil/efeitos adversos , Alprostadil/análogos & derivados , Analgésicos/uso terapêutico , Dor no Peito/tratamento farmacológico , Vasoespasmo Coronário/induzido quimicamente , Vasos Coronários/fisiopatologia , Feminino , Humanos , Cetoprofeno/análogos & derivados , Cetoprofeno/uso terapêutico , Mifepristona/efeitos adversos , Misoprostol/administração & dosagem , Gravidez , Segundo Trimestre da Gravidez/efeitos dos fármacos , Trometamina/análogos & derivados , Trometamina/uso terapêutico
4.
Breast J ; 16(2): 134-40, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20136644

RESUMO

The aim of this study was to validate a nomogram and a scoring system to predict non-sentinel lymph node status in breast cancer patients with sentinel lymph node (SLN) involvement. A total of 516 breast cancer patients underwent sentinel lymph node biopsy at our institution from January 2001 to August 2006. A prospective database was used to identify breast cancer patients with a positive SLN biopsy examination who underwent a completion axillary lymph node dissection. A total of 114 patients were identified. The Memorial Sloan-Kettering Cancer Center (MSKCC) nomogram and an axilla scoring system from Paris (Hôpital Tenon) were used to predict the probability of having non-SLN involvement. One hundred fourteen patients were included in the study. The areas under the receiver operating characteristics (ROC) curves were 0.671 (95% CI: 0.552-0.790) for the MSKCC nomogram and 0.703 (95% CI: 0.596-0.811) for the Tenon score. The univariate analysis shows that size of SLN metastases, the number of positive and negative SLN and the proportion of positive SLN were statistically significant. On multivariate logistic regression analysis, the size of SLN metastases and the proportion of positive SLN were statistically significant. The two scoring systems are similar according to their area under ROC curves, but should be improved to be valid and determinant to the general population. Meanwhile, the use of scoring systems could be applied in an individual manner in some patients.


Assuntos
Neoplasias da Mama/patologia , Biópsia de Linfonodo Sentinela , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Modelos Logísticos , Metástase Linfática , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC
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