251 research outputs found
Wave profile and tide monitoring system for scalable implementation
A versatile, miniaturized, cost-effective, low-power wave profile and tide monitoring system, capable of long-term and scalable deployment, was developed to integrate pressure and temperature sensors in an RS485 network, for standalone operation with organized memory or real-time shared data monitoring. The pressure and temperature sensors are controlled by low-power microcontrollers, that communicate the data periodically to a datalogger, that depending on the application, store it in a removable SD card or send it to a server via Wi-Fi. The data is then analyzed to compensate for the loss in amplitude sensitivity according to the sensor’s depth. The wave profile can be sampled at a maximum rate of 100 Hz, with a 1 cm resolution. The system was tested successfully in real-life conditions, in rivers Douro and Cávado, and off the coast of Viana do Castelo.João Rocha was supported by the doctoral Grant PRT/BD/154322/2023 financed by the Portuguese Foundation for Science and Technology (FCT), and with funds from Portuguese State Budget, European Social Fund (ESF) and Por_Norte, under MIT Portugal
Program. This work is co-funded by the projects K2D: Knowledge and Data from the Deep to Space (POCI-01-0247-FEDER-045941), SONDA (PTDC/EME-SIS/1960/2020), ATLÂNTIDA (NORTE-01-0145-FEDER-000040) and CMEMS - UIDB/04436/2020 and UIDP/04436/2020
Headspace solid-phase microextraction procedure for gas-chromatography analysis of toluene in urine
Toluene is widely used in industrial and laboratory applications and in many countries is related with social problems of abuse. Unaltered urinary toluene was introduced as a bioindicator of occupational exposure to the solvent, but its analysis presents difficulties due to the low levels of the compound excreted in urine. A gas-chromatography/flame ionization method for toluene in urine is described using headspace solid-phase microextraction and establishing the better conditions for two different extracting phases: polydimethylsiloxane (PDMS) and carboxen-PDMS. The carboxen-PDMS fiber showed lower quantifying limit (12.5 ng mL-1), better extraction efficiency (up to 28.1%) and repeatability (CV < 4.9%) than PDMS coating. The method was applied to analysis of toluene in urine of workers from car repair shops exposed to low solvent levels
Wave profile and tide monitoring system for scalable implementation
Apresentação de Poster em conferência Nacional.Presentation of a wave profile and tide monitoring system, with low-cost and low-power pressure sensors connected to a datalogger in a wired or acustic network
Myosteatosis in a systemic inflammation-dependent manner predicts favorable survival outcomes in locally advanced esophageal cancer
Increased adiposity and its attendant metabolic features as well as systemic inflammation have been associated with prognosis in locally advanced esophageal cancer (LAEC). However, whether myosteatosis and its combination with systemic inflammatory markers are associated with prognosis of esophageal cancer is unknown. Our study aimed to investigate the influence of myosteatosis and its association with systemic inflammation on progression-free survival (PFS) and overall survival (OS) in LAEC patients treated with definitive chemoradiotherapy (dCRT). We retrospectively gathered information on 123 patients with LAEC submitted to dCRT at the University of Campinas Hospital. Computed tomography (CT) images at the level of L3 were analyzed to assess muscularity and adiposity. Systemic inflammation was mainly measured by calculating the neutrophil-to-lymphocyte ratio (NLR). Median PFS for patients with myosteatosis (n = 72) was 11.0 months vs 4.0 months for patients without myosteatosis (n = 51) (hazard ratio [HR]: 0.53; 95% confidence interval [CI], 0.34-0.83; P = .005). Myosteatosis was also independently associated with a favorable OS. Systemic inflammation (NLR > 2.8) was associated with a worse prognosis. The combination of myosteatosis with systemic inflammation revealed that the subgroup of patients with myosteatosis and without inflammation presented less than half the risk of disease progression (HR: 0.47; 95% CI: 0.26-0.85; P = .013) and death (HR: 0.39; 95% CI, 0.21-0.72; P = .003) compared with patients with inflammation. This study demonstrated that myosteatosis without systemic inflammation was independently associated with favorable PFS and OS in LAEC patients treated with dCRT81669676976FAPESP – Fundação de Amparo à Pesquisa Do Estado De São Paulo2018/23428-
Evaluation of the effects of Quercetin and Kaempherol on the surface of MT-2 cells visualized by atomic force microscopy
AbstractThis study investigated the anti-viral effects of the polyphenolic compounds Quercetin and Kaempherol on the release of HTLV-1 from the surface of MT-2 cells. Atomic force microscopy (AFM) was used to scan the surface of the MT-2 cells. MT-2 cells were fixed with 100% methanol on round glass lamina or cleaved mica and dried under UV light and laminar flow. The images were captured on a Multimode equipment monitored by a NanoScope IIId controller from Veeco Instruments Inc operated in tapping mode and equipped with phase-imaging hardware. The images demonstrated viral budding structures 131±57nm in size, indicating profuse viral budding. Interestingly, cell-free viruses and budding structures visualized on the surface of cells were less common when MT-2 was incubated with Quercetin, and no particles were seen on the surface of cells incubated with Kaempherol. In summary, these data indicate that HTLV-1 is budding constantly from the MT-2 cell surface and that polyphenolic compounds were able to reduce this viral release. Biological samples were analyzed with crude cell preparations just after cultivation in the presence of Quercetin and Kaempherol, showing that the AFM technique is a rapid and powerful tool for analysis of antiviral activity of new biological compounds
PtOEP–PDMS-based optical oxygen sensor
The advanced and widespread use of microfluidic devices, which are usually fabricated in polydimethylsiloxane (PDMS), requires the integration of many sensors, always compatible with microfluidic fabrication processes. Moreover, current limitations of the existing optical and electrochemical oxygen sensors regarding long-term stability due to sensor degradation, biofouling, fabrication processes and cost have led to the development of new approaches. Thus, this manuscript reports the development, fabrication and characterization of a low-cost and highly sensitive dissolved oxygen optical sensor based on a membrane of PDMS doped with platinum octaethylporphyrin (PtOEP) film, fabricated using standard microfluidic materials and processes. The excellent mechanical and chemical properties (high permeability to oxygen, anti-biofouling characteristics) of PDMS result in membranes with superior sensitivity compared with other matrix materials. The wide use of PtOEP in sensing applications, due to its advantage of being easily synthesized using microtechnologies, its strong phosphorescence at room temperature with a quantum yield close to 50%, its excellent Strokes Shift as well as its relatively long lifetime (75 µs), provide the suitable conditions for the development of a miniaturized luminescence optical oxygen sensor allowing long-term applications. The influence of the PDMS film thickness (0.1–2.5 mm) and the PtOEP concentration (363, 545, 727 ppm) in luminescent properties are presented. This enables to achieve low detection levels in a gas media range from 0.5% up to 20%, and in liquid media from 0.5 mg/L up to 3.3 mg/L at 1 atm, 25 °C. As a result, we propose a simple and cost-effective system based on a LED membrane photodiode system to detect low oxygen concentrations for in situ applications.This work was co-financed by national funds through FCT—Fundação para a Ciência e Tecnologia, I.P. under project SONDA (PTDC/EME-SIS/1960/2020), by Programa Operacional Regional
do Norte (NORTE2020), through Fundo Europeu de Desenvolvimento Regional (FEDER), Project
NORTE-01-0145-FEDER-000032—NextSea, by the European Regional Development Fund (ERDF)
through INTERREG V-A Spain-Portugal Programme (POCTEP) 2014–2020, Project N. 0591_FOODSENS_1_E and by FCT national funds, under the national support to R&D units grants, through the reference projects UIDB/04436/2020 and UIDP/04436/2020
SARS-CoV-2 reinfection: report of two cases in Southeast Brazil
From February 26, 2020 to March 11, 2021, coronavirus disease 2019 (COVID-19) pandemic resulted in 11,439,558 cases and 277,102 deaths in Brazil. Among them, 2,195,130 cases and 63,965 deaths occurred in Sao Paulo State, Southeast Brazil. The recent emergence and rise of new variants of SARS-CoV-2 is of concern because of their higher transmissibility and possible association with more severe disease. Cases of SARS-CoV-2 reinfections have been described since December 2020 in Brazil. This report describes two cases of COVID-19 reinfection, that occurred five and six months after the first infection, during the second wave of the pandemic in Sao Paulo State. Both patients presented mild symptoms in the two COVID-19 episodes and different lineages of SARS-CoV-2 were identified: B.1.1.33 and B.1.1.28 lineages in case 1 and B1.1.128 and P. 2 lineages in case 2
Exposição a pesticidas e genótipo heterozigoto de GSTP1-Alw26I associam-se à doença de Parkinson
Objective This study aimed to analyze the frequency of GSTP1-Alw26I polymorphism and to estimate its association with toxic substances in Parkinson's disease (PD). Methods A study group with 154 patients - subdivided into familial and sporadic PD groups - and 158 elderly individuals without the disease (control group) were evaluated. GSTP1-Alw26I polymorphism was analyzed by polymerase chain reaction/restriction fragment length polymorphism (PCR-RFLP). Results Patients were significantly more exposed to pesticides compared with the control group (p=0.0004), and the heterozygote genotype associated to exposure to pesticides also prevailed in patients (p=0.0001). Wild homozygote genotype was related to tobacco use (p=0.043) and alcoholism (p=0.033) in familial PD patients. Conclusion Exposure to pesticides is associated to PD, whose effect can be enhanced when combined with the heterozygote genotype of GSTP1-Alw26I. Also, large genetic and environmental studies considering tobacco use, alcoholism, GSTP1 and PD are necessary to confirm our findings.Objetivo Analisar a frequência do polimorfismo GSTP1-Alw26I, assim como estimar sua associação com substâncias tóxicas na doença de Parkinson (DP). Métodos A casuÃstica avaliada foi composta por um grupo de estudo, com 154 pacientes, subdivididos em DP familial e esporádica, e outro com 158 idosos sem a doença (grupo controle). O polimorfismo GSTP1-Alw26I foi analisado por reação em cadeia da polimerase/polimorfismo de comprimento do fragmento de restrição (PCR/RFLP). Resultados Os pacientes foram significativamente mais expostos a pesticidas, comparados com o grupo controle (p=0,0004), e o genótipo heterozigoto associado a exposição a pesticidas também prevaleceu nos pacientes (p=0,0001). O genótipo homozigoto selvagem apresentou relação com tabagismo (p=0,043) e etilismo (p=0,033) em pacientes com DP familial. Desse modo, a exposição a pesticidas está associada à DP, cujo efeito pode ser potencializado quando combinado ao genótipo heterozigoto de GSTP1-Alw26I. Estudos genético-ambientais envolvendo tabagismo, etilismo, GSTP1 e DP devem ser realizados em casuÃsticas numerosas, confirmando essa associação.Sao Jose do Rio Preto Medical School Department of NeuroscienceFAMERPFederal University of São PauloHospital de BaseUNIFESPSciEL
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