An Optimized Self-Compensated Solution for Temperature and Strain Cross-Sensitivity in FBG Interrogators Based on Edge Filter.

Optical fiber sensors based on fiber Bragg gratings (FBGs) are prone to measurement errors if the cross-sensitivity between temperature and strain is not properly considered. This paper describes a self-compensated technique for canceling the undesired influence of temperature in strain measurement. An edge-filter-based interrogator is proposed and the central peaks of two FBGs (sensor and reference) are matched with the positive and negative slopes of a Fabry-Perot interferometer that acts as an optical filter. A tuning process performed by the grey wolf optimizer (GWO) algorithm is required to determine the optimal spectral characteristics of each FBG. The interrogation range is not compromised by the proposed technique, being determined by the spectral characteristics of the optical filter in accordance with the traditional edge-filtering interrogation. Simulations show that, by employing FBGs with optimal characteristics, temperature variations of 30 °C led to an average relative error of 3.4% for strain measurements up to 700µÏµ. The proposed technique was experimentally tested under non-ideal conditions: two FBGs with spectral characteristics different from the optimized results were used. The temperature sensibility decreased by 50.8% as compared to a temperature uncompensated interrogation system based on an edge filter. The non-ideal experimental conditions were simulated and the maximum error between theoretical and experimental data was 5.79%, proving that the results from simulation and experimentation are compatible.

Impact of early detection of acute invasive fungal rhinosinusitis in immunocompromised patients.

BACKGROUND: Early diagnosis of acute invasive fungal rhinosinusitis (AIFRS) is vital to improving outcomes in immunocompromised patients. This study evaluated the impact of a systematic protocol with nasal endoscopy and biopsies to early detect AIFRS in immunocompromised patients. Additionally, we compared the accuracy of frozen-section biopsy and culture with formalin-fixed paraffin-embedded (FFPE) biopsy. METHODS: Retrospective cohort in a Tertiary Referral Hospital. Patients with the suspected diagnosis of AIFRS were evaluated following a standardized protocol, including serial nasal endoscopies and biopsies when necessary. The sensitivity and specificity of frozen-section biopsy and culture were also compared with FFPE. RESULTS: The mortality rate related to AIFRS of this standardized cohort (13/43) was 30.2%. Better outcomes were observed in patients with disease limited to the turbinates and in those with higher peripheral neutrophils count. Frozen-section biopsy positivity correlated with FFPE findings for fungi detection (p-value < 0.0001), with a sensitivity of 90.6%, specificity of 72.7%, and accuracy of 86.0%. CONCLUSION: Implementation of this standardized protocol was related to a considerably low mortality rate among patients with suspected AIFRS at our Institution. Frozen-section biopsy revealed high accuracy to diagnose AIFRS. The current protocol including frozen-tissue biopsy improved the evaluation and survival rates of immunocompromised patients with presumed AIFRS.

The importance of clinical monitoring for compliance with Continuous Positive Airway Pressure / A importância do seguimento clínico para adesão ao CPAP

Abstract Introduction: Obstructive sleep apnea syndrome is currently a public health problem of great importance. When misdiagnosed or improperly treated, it can lead to serious consequences on patients' quality of life. The gold standard treatment for cases of obstructive sleep apnea syndrome, especially in mild to severe and symptomatic cases, is continuous positive airway pressure therapy. Compliance with continuous positive airway pressure therapy is directly dependent on the active participation of the patient, which can be influenced by several factors. Objective: The objective of this study is to describe the factors related to compliance with continuous positive airway pressure therapy, and to analyze which associated factors directly influence the efficiency of the treatment. Methods: Patients who received continuous positive airway pressure therapy through the Municipal Health Department of the city of Ribeirão Preto were recruited. A structured questionnaire was administered to the patients. Compliance with continuous positive airway pressure therapy was assessed by average hours of continuous positive airway pressure therapy usage per night. Patients with good compliance (patients using continuous positive airway pressure therapy ≥4 h/night) were compared to those with poor compliance (patients using <4 h/night). Results: 138 patients were analyzed: 77 (55.8%) were considered compliant while 61 (44.2%) were non-compliant. The comparison between the two groups showed that regular monitoring by a specialist considerably improved compliance with continuous positive airway pressure therapy (odds ratio, OR = 2.62). Conclusion: Compliance with continuous positive airway pressure therapy is related to educational components, which can be enhanced with continuous and individualized care to patients with obstructive sleep apnea syndrome.

Resumo Introdução: Síndrome da apneia obstrutiva do sono (SAOS) é, atualmente, um problema de saúde pública de suma importância. Quando mal diagnosticada ou tratada inadequadamente, pode levar a sérias consequências na qualidade de vida do paciente. O tratamento padrão-ouro para casos de SAOS, principalmente nos casos moderados a grave e sintomáticos, é o CPAP (Continuous Positive Airway Pressure). A adesão ao CPAP depende diretamente da participação ativa do paciente, que pode ser influenciada por vários fatores. Objetivo: O objetivo deste estudo é descrever os fatores relacionados à adesão ao CPAP e analisar quais fatores associados influenciam diretamente na eficiência do tratamento. Método: Foram recrutados pacientes que receberam CPAP pela Secretaria Municipal de Saúde de Ribeirão Preto. Um questionário estruturado foi aplicado ao paciente. A adesão ao CPAP foi avaliada pela média de horas de uso do CPAP por noite. Pacientes com boa adesão (pacientes em uso de CPAP ≥4 horas/noite) foram comparados aos com má adesão (pacientes em uso < 4 horas/noite). Resultados: No estudo, 138 pacientes foram analisados: 77 (55,8%) foram considerados aderentes e 61 (44,2%) foram não aderentes. A comparação entre os dois grupos demonstrou que o seguimento regular com especialista melhorou consideravelmente a adesão ao CPAP (odds ratio, OR = 2,62). Conclusão: A adesão ao CPAP está relacionada a componentes educacionais, que podem ser aprimorados com assistência contínua e individualizada ao paciente com SAOS.

The importance of clinical monitoring for compliance with Continuous Positive Airway Pressure.

INTRODUCTION: Obstructive sleep apnea syndrome is currently a public health problem of great importance. When misdiagnosed or improperly treated, it can lead to serious consequences on patients' quality of life. The gold standard treatment for cases of obstructive sleep apnea syndrome, especially in mild to severe and symptomatic cases, is continuous positive airway pressure therapy. Compliance with continuous positive airway pressure therapy is directly dependent on the active participation of the patient, which can be influenced by several factors. OBJECTIVE: The objective of this study is to describe the factors related to compliance with continuous positive airway pressure therapy, and to analyze which associated factors directly influence the efficiency of the treatment. METHODS: Patients who received continuous positive airway pressure therapy through the Municipal Health Department of the city of Ribeirão Preto were recruited. A structured questionnaire was administered to the patients. Compliance with continuous positive airway pressure therapy was assessed by average hours of continuous positive airway pressure therapy usage per night. Patients with good compliance (patients using continuous positive airway pressure therapy ≥4h/night) were compared to those with poor compliance (patients using <4h/night). RESULTS: 138 patients were analyzed: 77 (55.8%) were considered compliant while 61 (44.2%) were non-compliant. The comparison between the two groups showed that regular monitoring by a specialist considerably improved compliance with continuous positive airway pressure therapy (odds ratio, OR=2.62). CONCLUSION: Compliance with continuous positive airway pressure therapy is related to educational components, which can be enhanced with continuous and individualized care to patients with obstructive sleep apnea syndrome.

Effect of 3-alkylpyridine marine alkaloid analogues in Leishmania species related to American cutaneous leishmaniasis.

A series of oxygenated analogues of marine 3-alkylpyridine alkaloids were synthesized, and their leishmanicidal activity was assayed. All compounds were prepared from 3-pyridinepropanol in few steps and in good yields. The key step for the synthesis of these compounds was a classic Williamson etherification under phase-transfer conditions. Besides toxicity in peritoneal macrophages, the compounds exhibited a significant leishmanicidal activity. Of twelve compounds tested, five showed a strong leishmanicidal activity against promastigote forms of Leishmania amazonensis and L. braziliensis with IC50 below 10 µm. Compounds 11, 14, 15, and 16 showed a strong leishmanicidal activity on intracellular amastigotes (IC50 values of 2.78; 0.27; 1.03, and 1.33 µm, respectively), which is unlikely to be owing to the activation of nitric oxide production by macrophages.

Synthesis and evaluation of antimalarial activity of oxygenated 3-alkylpyridine marine alkaloid analogues.

A series of new oxygenated analogues of marine 3-alkylpyridine alkaloids were prepared from 3-pyridinepropanol in few steps and in good yields. The key step for the synthesis of these compounds was a Williamson etherification under phase-transfer conditions. All new compounds were evaluated for their antiplasmodial activity and cytotoxicity. A significant reduction in parasitaemia was observed for some of the prepared compounds, and the majority of them exhibited a selectivity index (SI) ranging from 2.78 to 15.58, which suggests that these compounds may be a promising class of substances with antimalarial activity.