720 research outputs found
Incorporation of dual-stimuli responsive microgels in nanofibrous membranes for cancer treatment by magnetic hyperthermia
Funding Information: This work is funded by FEDER funds through the COMPETE 2020 Program and National Funds through FCT?Portuguese Foundation for Science and Technology under the project POCI?01-0145-FEDER-007688 (Reference UID/CTM/50025) and PTDC/CTMCTM/30623/2017 (DREaMM).The delivery of multiple anti-cancer agents holds great promise for better treatments. The present work focuses on developing multifunctional materials for simultaneous and local combi-natory treatment: Chemotherapy and hyperthermia. We first produced hybrid microgels (MG), synthesized by surfactant-free emulsion polymerization, consisting of Poly (N-isopropyl acrylamide) (PNIPAAm), chitosan (40 wt.%), and iron oxide nanoparticles (NPs) (5 wt.%) as the inorganic compo-nent. PNIPAAm MGs with a hydrodynamic diameter of about 1 µm (in their swollen state) were successfully synthesized. With the incorporation of chitosan and NPs in PNIPAAm MG, a decrease in MG diameter and swelling capacity was observed, without affecting their thermosensitivity. We then sought to produce biocompatible and mechanically robust membranes containing these dual-responsive MG. To achieve this, MG were incorporated in poly (vinyl pyrrolidone) (PVP) fibers through colloidal electrospinning. The presence of NPs in MG decreases the membrane swelling ratio from 10 to values between 6 and 7, and increases the material stiffness, raising its Young modulus from 20 to 35 MPa. Furthermore, magnetic hyperthermia assay shows that PVP-MG-NP composites perform better than any other formulation, with a temperature variation of about 1◦C. The present work demonstrates the potential of using multifunctional colloidal membranes for magnetic hyperthermia and may in the future be used as an alternative treatment for cancer.publishersversionpublishe
Comparative study of risk factors among children and adolescents with an anthropometric diagnosis of overweight or obesity
OBJETIVO: O excesso de peso é um grande problema de saúde pública em todo o mundo, atingindo crianças e adolescentes. O presente estudo teve por objetivo verificar se a condição de portador de sobrepeso se associa à presença de fatores de risco à saúde. MÉTODOS: Foram estudados 84 sujeitos entre seis e 17 anos, constituindo-se um grupo de 34 pacientes portadores de sobrepeso e outro de 50 obesos, atendidos em ambulatório de Nutrologia Pediátrica da Universidade de Ribeirão Preto (Unaerp), durante o período de outubro de 2004 a outubro de 2005. Foram obtidas as variáveis: pressão arterial, circunferência abdominal, glicemia de jejum, glicemia de segunda hora, colesterol total, HDL-c, LDL-c e triglicérides. Comparam-se os dois grupos por meio de duas abordagens estatísticas: comparação entre as distribuições dos valores absolutos (teste de Mann-Whitney) e entre as frequências de valores considerados alterados (teste exato de Fisher). RESULTADOS: Quanto à primeira abordagem, verificou-se diferença estatística apenas para o HDL-c, com maiores valores para o subgrupo de portadores de sobrepeso de seis a dez anos. Quanto à segunda comparação, verificou-se diferença estatística para a circunferência abdominal (segundo os critérios de Freedman), HDL-c e glicemia de jejum, com maiores frequências de valores alterados entre os obesos. CONCLUSÕES: Os portadores de sobrepeso apresentaram alterações indicativas de prejuízos à sua saúde, semelhantemente aos obesos, sendo necessário também incluí-los nos programas de prevenção e tratamento.OBJECTIVE: Excess weight is a serious public health problem all over the world, affecting children and adolescents. The objective of the present study was to determine whether the condition of being overweight is associated to changes in health parameters. METHODS: 84 subjects aged 6-17 years old were studied (34 overweight and 50 obese patients), all of them assisted at the Pediatric Nutrology outpatient clinic of the University of Ribeirão Preto (Unaerp) from October/2004 to October/2005. Arterial pressure, abdominal circumference, fast glycemia, second hour glycemia, total cholesterol and its fractions (HDL-c and LDL-c) and triglycerides were determined. The two groups were compared by two statistical approaches: comparison of absolute values by Mann-Whitney test, and between frequencies of altered values by Fisher exact test. RESULTS: There was a statistical difference only for HDL-c, with higher concentrations in the overweight group when the subgroup of patients with 6-10 years old was considered. Regarding the second approach, there were statistical differences in the abdominal circumference by Freedman criteria, HDL-c and fast glycemia, with higher frequencies of altered values among obese subjects. CONCLUSIONS: Overweight patients presented alterations harmful to their health, similarly to obese individuals. It is necessary to enroll overweight children and adolescents in programs dedicated to the prevention and treatment of nutritional problems
Treatment outcomes of pulp revascularization in traumatized immature teeth using calcium hydroxide and 2% chlorhexidine gel as intracanal medication
Objective: Pulp revascularization is an effective treatment for immature necrotic teeth. Calcium hydroxide has been used in pulp revascularization as an intracanal medication due to its antimicrobial action and the non-exhibition of crown discoloration and cytotoxicity for stem cells from the apical papilla. Our study aimed to investigate the clinical success and quantitative radiographic changes of root development in immature traumatized teeth using calcium hydroxide plus 2% chlorhexidine gel as intracanal medication. Methodology: In this retrospective study, 16 patients were treated with a standardized pulp revascularization protocol. Calcium hydroxide and 2% chlorhexidine gel were manipulated in a 1:1 (v/v) ratio and inserted into root canals with Lentulo spirals (Dentsply Maillefer, Baillaigues, Switzerland). Patients were followed up for a period from 9 to 36 months for the evaluation of clinical and radiological data. Radiographic measurements of root length, root width, apical diameter, and MTA placement from the apex were quantified using software ImageJ. Wilcoxon test and t-test were used, according to nonparametric or parametric data, respectively, for changes over time in root length, root width, and apical diameter. Results: Fifteen teeth survived during the follow-up period (93.75%) and met the criteria for clinical success. Although the changes seem to be very small in many cases, significant increases in the average root length (14.28%, p<0.0001), root width (8.12%, p=0.0196), and decrease in apical diameter (48.37%, p=0.0007) were observed. MTA placement from the apex and age at the time of treatment was not significantly associated with the quantitative radiographic outcomes. Conclusions: Pulp revascularization in traumatized immature teeth treated with calcium hydroxide plus 2% chlorhexidine gel as intracanal medication had high success and survival rates, showing periodontal healing and resolution of signs and symptoms. However, concerning the continued root development, the outcomes can still be considered unpredictable
A Treatment with a Protease Inhibitor Recombinant from the Cattle Tick (Rhipicephalus Boophilus microplus) Ameliorates Emphysema in Mice
Aims: To determine whether a serine protease inhibitor treatment can prevent or minimize emphysema in mice.Methods: C57BL/6 mice were subjected to porcine pancreatic elastase (PPE) nasal instillation to induce emphysema and were treated with a serine protease inhibitor (rBmTI-A) before (Protocol 1) and after (Protocol 2) emphysema development. in both protocols, we evaluated lung function to evaluate the airway resistance (Raw), tissue damping (Gtis) and tissue elastance (Htis). the inflammatory profile was analyzed in the bronchoalveolar lavage (BALF) and through the use of morphometry; we measured the mean linear intercept (Lm) (to verify alveolar enlargement), the volume proportion of collagen and elastic fibers, and the numbers of macrophages and metalloprotease 12 (MMP-12) positive cells in the parenchyma. We showed that at both time points, even after the emphysema was established, the rBmTI-A treatment was sufficient to reverse the loss of elastic recoil measured by Htis, the alveolar enlargement and the increase in the total number of cells in the BALF, with a primary decrease in the number of macrophages. Although, the treatment did not control the increase in macrophages in the lung parenchyma, it was sufficient to decrease the number of positive cells for MMP-12 and reduce the volume of collagen fibers, which was increased in PPE groups. These findings attest to the importance of MMP-12 in PPE-induced emphysema and suggest that this metalloprotease could be an effective therapeutic target.Laboratorios de Investigacao Medica do Hospital das Clinicas da Faculdade de Medicina da USP (LIM/HC)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Univ São Paulo, Dept Med, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biol Sci, São Paulo, BrazilUNIFESP EPM, Dept Bioquim, São Paulo, BrazilUFABC, Ctr Ciencias Nat & Humanas, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biol Sci, São Paulo, BrazilUNIFESP EPM, Dept Bioquim, São Paulo, BrazilWeb of Scienc
The contribution of meteorological parameters and the COVID-19 partial lockdown on air quality in Rio de Janeiro, Brazil
This study evaluated the pollutant levels (NO2, SO2, CO, and O3), air quality index (AQI) and
the influence of meteorological variables and coronavirus disease (COVID-19) pandemic on the
air quality in Rio de Janeiro. The data set used comprises periods before (March-April, 2019) and
during pandemic (March-April, 2020). According to the AQI results, on most days, the air quality
was ranked as “good”. Brazilian air quality standards for SO2, O3, and NO2 were not exceeded in
any of the monitoring stations during partial lockdown, while CO exceeded in all periods in one
site due to industrial emission. Comparing both periods, descriptive statistics for the meteorological
parameters presented no differences, which suggests similar conditions. However, when evaluated
week by week in 2020, weather conditions presented some differences that probably affected
pollutant concentrations. The correlations between O3 and NO2 and some meteorological parameters
indicate that variations in both favored ozone formation, since it is a photochemical process favored
by temperature and solar radiation and that, in Rio de Janeiro, low NO2 concentrations lead to
increased O3. The improvements on air quality during the partial lockdown may be attributed
mainly to a reduction on emission sources rather than weather conditions.Campus Lima Centr
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