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1.
Sensors (Basel) ; 23(12)2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37420767

RESUMO

In this research, we present a prototype optical system that offers significant advances in detecting hydrochloric acid (HCl) and ammonia (NH3) vapors. The system utilizes a natural pigment sensor based on Curcuma longa that is securely attached to a glass surface support. Through extensive development and testing with HCl (37% aqueous solution) and NH3 (29% aqueous solution) solutions, we have successfully demonstrated the effectiveness of our sensor. To facilitate the detection process, we have developed an injection system that exposes C. longa pigment films to the targeted vapors. The interaction between the vapors and the pigment films triggers a distinct color change, which is then analyzed by the detection system. By capturing the transmission spectra of the pigment film, our system allows a precise comparison of these spectra at different concentrations of the vapors. Our proposed sensor exhibits remarkable sensitivity, allowing the detection of HCl at a concentration of 0.009 ppm using only 100 µL (2.3 mg) of pigment film. In addition, it can detect NH3 at a concentration of 0.03 ppm with a 400 µL (9.2 mg) pigment film. Integrating C. longa as a natural pigment sensor in an optical system opens up new possibilities for detecting hazardous gases. The simplicity and efficiency of our system, combined with its sensitivity, make it an attractive tool in environmental monitoring and industrial safety applications.


Assuntos
Amônia , Ácido Clorídrico , Curcuma , Gases , Água
2.
Lupus ; 32(6): 737-745, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37036020

RESUMO

OBJECTIVE: During the COVID-19 pandemic, many research studies were adapted, including our longitudinal study examining cognitive impairment (CI) in systemic lupus erythematosus (SLE). Cognitive testing was switched from in-person to virtual. This analysis aimed to determine if the administration method (in-person vs. virtual) of the ACR-neuropsychological battery (ACR-NB) affected participant cognitive performance and classification. METHODS: Data from our multi-visit, SLE CI study included demographic, clinical, and psychiatric characteristics, and the modified ACR-NB. Three analyses were undertaken for cognitive performance: (1) all visits, (2) non-CI group visits only and (3) intra-individual comparisons. A retrospective preferences questionnaire was given to participants who completed the ACR-NB both in-person and virtually. RESULTS: We analysed 328 SLE participants who had 801 visits (696 in-person and 105 virtual). Demographic, clinical, and psychiatric characteristics were comparable except for ethnicity, anxiety and disease-related damage. Across all three comparisons, six tests were consistently statistically significantly different. CI classification changed in 11/71 (15%) participants. 45% of participants preferred the virtual administration method and 33% preferred in-person. CONCLUSIONS: Of the 19 tests in the ACR-NB, we identified one or more problems with eight (42%) tests when moving from in-person to virtual administration. As the use of virtual cognitive testing will likely increase, these issues need to be addressed - potentially by validating a virtual version of the ACR-NB. Until then, caution must be taken when directly comparing virtual to in-person test results. If future studies use a mixed administration approach, this should be accounted for during analysis.


Assuntos
COVID-19 , Lúpus Eritematoso Sistêmico , Reumatologia , Humanos , Estados Unidos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/psicologia , Estudos Retrospectivos , Estudos Longitudinais , Pandemias , COVID-19/complicações , Cognição
3.
J Dent Res ; 102(4): 391-401, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36631957

RESUMO

This study compares the effectiveness of pharmacological treatments to develop guidelines for the management of acute pain after tooth extraction. We searched Medline, EMBASE, CENTRAL, and US Clinical Trials registry on November 21, 2020. We included randomized clinical trials (RCTs) of participants undergoing dental extractions comparing 10 interventions, including acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), opioids, and combinations to placebo. After duplicate screening and data abstraction, we conducted a frequentist network meta-analysis for each outcome at 6 h (i.e., pain relief, total pain relief [TOTPAR], summed pain intensity difference [SPID], global efficacy rating, rescue analgesia, and adverse effects). We assessed the risk of bias using a modified Cochrane RoB 2.0 tool and the certainty of evidence using the Grading of Recommendations, Assessment, Development, and Evaluation approach. We implemented the analyses in RStudio version 3.5.3 and classified interventions from most to least beneficial or harmful. We included 82 RCTs. Fifty-six RCTs enrolling 9,095 participants found moderate- and high-certainty evidence that ibuprofen 200 to 400 mg plus acetaminophen 500 to 1,000 mg (mean difference compared to placebo [MDp], 1.68; 95% confidence interval [CI], 1.06-2.31), acetaminophen 650 mg plus oxycodone 10 mg (MDp, 1.19; 95% CI, 0.85-1.54), ibuprofen 400 mg (MDp, 1.31; 95% CI, 1.17-1.45), and naproxen 400-440 mg (MDp, 1.44; 95% CI, 1.07-1.80) were most effective for pain relief on a 0 to 4 scale. Oxycodone 5 mg, codeine 60 mg, and tramadol 37.5 mg plus acetaminophen 325 mg were no better than placebo. The results for TOTPAR, SPID, global efficacy rating, and rescue analgesia were similar. Based on low- and very low-certainty evidence, most interventions were classified as no more harmful than placebo for most adverse effects. Based on moderate- and high-certainty evidence, NSAIDs with or without acetaminophen result in better pain-related outcomes than opioids with or without acetaminophen (except acetaminophen 650 mg plus oxycodone 10 mg) or placebo.


Assuntos
Acetaminofen , Dor Aguda , Adulto , Humanos , Acetaminofen/uso terapêutico , Ibuprofeno/uso terapêutico , Oxicodona/uso terapêutico , Metanálise em Rede , Anti-Inflamatórios não Esteroides/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologia , Analgésicos Opioides/uso terapêutico , Extração Dentária/efeitos adversos , Dor Aguda/tratamento farmacológico , Dor Aguda/etiologia
4.
Opt Express ; 29(15): 23439-23446, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34614609

RESUMO

In this paper, we present a novel mechanism for the generation of laser pulses based on the phenomenon of thermocavitation. Thermocavitation bubbles were generated within a glass cuvette filled with copper nitrate dissolved in water, where the tip of an optical fiber was placed very close to the bubble generation region. Once the bubble is generated, it expands rapidly and the incoming laser light transmitted through the optical fiber is reflected at the vapor-solution interface and reflected back into the fiber, which is coupled to an erbium-doped fiber ring laser. Laser pulses were extracted from the ring cavity and detected by a fast photodetector, which corresponds to a single thermocavitation event, obtaining a pulse repetition rate from 118 Hz to 2 kHz at 1560 nm, with a pulse width ranging from 64 to 57 µs. The repetition rate can be controlled by adjusting the laser power to induce thermocavitation. To our knowledge, this novel mechanism of laser pulses has not been reported in the literature.

6.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 410-413, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018015

RESUMO

Atrial fibrillation (AF) is an irregular heart rhythm due to disorganized atrial electrical activity, often sustained by rotational drivers called rotors. In the present work, we sought to characterize and discriminate whether simulated single stable rotors are located in the pulmonary veins (PVs) or not, only by using non-invasive signals (i.e., the 12-lead ECG). Several features have been extracted from the signals, such as Hjort descriptors, recurrence quantification analysis (RQA), and principal component analysis. All the extracted features have shown significant discriminatory power, with particular emphasis to the RQA parameters. A decision tree classifier achieved 98.48% accuracy, 83.33% sensitivity, and 100% specificity on simulated data.Clinical Relevance-This study might guide ablation procedures, suggesting doctors to proceed directly in some patients with a pulmonary veins isolation, and avoiding the prior use of an invasive atrial mapping system.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Fibrilação Atrial/diagnóstico , Eletrocardiografia , Humanos , Veias Pulmonares/cirurgia , Resultado do Tratamento
7.
Opt Express ; 28(4): 4928-4937, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32121723

RESUMO

Numerical simulations using the Finite-Difference Time-Domain method were used to study the propagation of an acoustic wave within a truncated ellipsoidal cavity. Based in our simulations, a fluidic device was designed and fabricated using a 3D printer in order to focus an acoustic wave more efficiently and expel a liquid jet. The device consists of an ellipsoidal shaped chamber filled with a highly absorbent solution at the operating wavelength (1064 nm) in order to create a vapor bubble using a continuous wavelength laser. The bubble rapidly expands and collapses emitting an acoustic wave that propagates inside the cavity, which was measured by using a needle hydrophone. The bubble collapse, and source of the acoustic wave, occurs in one focus of the cavity and the acoustic wave is focused on the other one, expelling a liquid jet to the exterior. The physical mechanism of the liquid jet generation is momentum transfer from the acoustic wave, which is strongly focused due to the geometry of the cavity. This mechanism is different to the methods that uses pulsed lasers for the same purpose. The maximum speed of the generated liquid microjets was approximately 20 m/s. One potential application of this fluidic device can be found for inkjet printing, coating and, maybe the most attractive, for drug delivery.

8.
Opt Express ; 26(2): 1556-1563, 2018 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-29402029

RESUMO

In this work, the influence of induced losses on the saturable absorption by zinc nanoparticles photodeposited onto the core of an optical fiber end is reported. Samples with different losses were obtained by the photodeposition technique using a continuous wave laser at 1550 nm. The nonlinear absorption of the saturable absorber was characterized by the P-scan technique using a high-gain pulsed erbium-doped fiber amplifier. The results have demonstrated that for optical fibers with variable induced losses by deposited nanoparticles, the modulation depth increases proportionally based on the nonlinear absorption coefficient. With induced losses fixed at 3 dB, it was demonstrated that the modulation depth increased as a function of the optical power used in the photodeposition process. The saturation intensity of the saturable absorber presents small shifts for higher intensities.

9.
Clin Exp Immunol ; 191(2): 229-239, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28963724

RESUMO

Itolizumab is a humanized anti-CD6 monoclonal antibody (mAb) that has previously shown encouraging results, in terms of safety and positive clinical effects, in a 6-week monotherapy clinical trial conducted in rheumatoid arthritis (RA) patients. The current Phase I study evaluated the safety and clinical response for a longer treatment of 12 itolizumab intravenous doses in subjects with active RA despite previous disease-modifying anti-rheumatic drug (DMARD) therapy. Twenty-one subjects were enrolled into four dosage groups (0·1, 0·2, 0·4 and 0·8 mg/kg). Efficacy end-points including American College of Rheumatology (ACR)20, ACR50 and ACR70 response rates and disease activity score in 28 joints (DAS28) were monitored at baseline and at specific time-points during a 10-week follow-up period. Itolizumab was well tolerated up to the highest tested dose. No related serious adverse events were reported and most adverse events were mild. Remarkably, itolizumab treatment did not produce lymphopenia and, therefore, was not associated with infections. All patients achieved a clinical response (ACR20) at least once during the study. Eleven subjects (55%) achieved at least a 20% improvement in ACR just 1 week after the first itolizumab administration. The clinical response was observed from the beginning of the treatment and was sustained during 24 weeks. The efficacy profile of this 12-week treatment was similar to that of the previous study (6-week treatment). These results reinforce the safety profile of itolizumab and provide further evidence on the clinical benefit from the use of this anti-CD6 mAb in RA patients.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Adolescente , Adulto , Idoso , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Cuba , Progressão da Doença , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Seguimentos , Humanos , Linfopenia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Appl Opt ; 56(25): 7167-7173, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29047977

RESUMO

A high-velocity fluid stream ejected from an orifice or nozzle is a common mechanism to produce liquid jets in inkjet printers or to produce sprays among other applications. In the present research, we show the generation of liquid jets of controllable direction produced within a sessile water droplet by thermocavitation. The jets are driven by an acoustic shock wave emitted by the collapse of a hemispherical vapor bubble at the liquid-solid/substrate interface. The generated shock wave is reflected at the liquid-air interface due to acoustic impedance mismatch generating multiple reflections inside the droplet. During each reflection, a force is exerted on the interface driving the jets. Depending on the position of the generation of the bubble within the droplet, the mechanical energy of the shock wave is focused on different regions at the liquid-air interface, ejecting cylindrical liquid jets at different angles. The ejected jet angle dependence is explained by a simple ray tracing model of the propagation of the acoustic shock wave inside the droplet.

13.
Physiol Meas ; 38(7): 1426-1440, 2017 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-28497774

RESUMO

OBJECTIVE: The aim of this work was to evaluate the potential changes in the ballistocardiogram (BCG) signal induced by different respiratory patterns and posture, by using the dynamic time warping (DTW) technique. APPROACH: BCG signals were recorded in a group of 20 healthy volunteers, simultaneously with an electrocardiogram (ECG). Two recordings, one in a supine (SUP) and one in a standing (ST) position, including spontaneous breathing, two 1 min apneas (at full and empty-lungs, respectively) and 30 s of Valsalva, were analyzed. A warped averaged waveform was computed for each phase, from which amplitude and temporal parameters were extracted to characterize each condition. MAIN RESULTS: Variations were found in both amplitude and duration of BCG-derived parameters among manoeuvres, especially when compared to spontaneous breathing, suggesting a complex interaction between intra-thoracic pressure changes acting on venous return, together with the autonomic nervous system modulation on heart rate. The effect of a hydrostatic pressure gradient elicited by postural conditions was also evident. SIGNIFICANCE: Posture and respiratory manoeuvres affect the BCG signal in different ways, probably as a result of changes induced in preload and afterload. This supports the need to define separate normality ranges for each posture and/or breathing conditions, as well as the importance of applying specific manoeuvres to highlight any pathological response in the computed BCG parameters.


Assuntos
Balistocardiografia , Postura/fisiologia , Respiração , Processamento de Sinais Assistido por Computador , Adulto , Feminino , Frequência Cardíaca , Humanos , Masculino , Fatores de Tempo
14.
J Antimicrob Chemother ; 71(12): 3449-3452, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27543657

RESUMO

OBJECTIVES: To evaluate the in vitro activity of anidulafungin combined with amphotericin B or voriconazole against Candida spp. biofilms. METHODS: Four Candida albicans, four Candida tropicalis, four Candida glabrata, two Candida parapsilosis and two Candida orthopsilosis blood isolates were tested by the microdilution chequerboard method combined with the XTT metabolic assay. Biofilm MIC was defined as the lowest concentration producing 50% metabolic inhibition with respect to control (BMIC50). Concentrations in the combinations ranged from 1/8 × BMIC50 to 4 × BMIC50 found for each antifungal tested alone. RESULTS: Anidulafungin plus amphotericin B acted synergistically against C. albicans and C. glabrata biofilms [fractional inhibitory concentration index (FICI): 0.082-0.387], but showed no interaction against C. tropicalis, C. parapsilosis and C. orthopsilosis (FICI: 0.516-2.099). The combination of these antifungals failed to completely remove biofilms of C. albicans and C. glabrata, decreasing the metabolic activity of the biofilms up to 80% and 95%, respectively, which did not occur when each antifungal was used alone. Anidulafungin plus voriconazole showed no interaction against all isolates. Using a less stringent criterion previously proposed to define synergism (FICI < 1) and antagonism (FICI > 1.25), antagonistic interactions were found against some isolates. CONCLUSIONS: Anidulafungin with amphotericin B results in a synergistic effect against C. albicans and C. glabrata biofilms at serum concentrations of the drugs, but showed no interaction against C. tropicalis and C. parapsilosis complex. Anidulafungin plus voriconazole showed no interaction against the five Candida species assayed. Biofilms of C. tropicalis were found to be the most resistant towards the combinations assayed. The results presented may be of potential interest in the clinical setting.


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Equinocandinas/farmacologia , Voriconazol/farmacologia , Anidulafungina , Candida/isolamento & purificação , Candida/fisiologia , Candidemia/microbiologia , Sinergismo Farmacológico , Humanos , Testes de Sensibilidade Microbiana
15.
Physiol Meas ; 36(10): 2041-55, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26289679

RESUMO

It is well known that prolonged microgravity leads to cardiovascular deconditioning, inducing significant changes in autonomic control of the cardiovascular system. This may adversely influence cardiac repolarization, and provoke cardiac rhythm disturbances. T-wave alternans (TWA), reflecting temporal and spatial repolarization heterogeneity, could be affected. The aim of this work was to test the hypothesis that 5 d and 21 d head-down (-6°) bed rest (HDBR) increases TWA, thus suggesting a higher underlying electrical instability and related arrhythmogenic risk. Forty-four healthy male volunteers were enrolled in the experiments as part of the European Space Agency's HDBR studies. High-fidelity ECG was recorded during orthostatic tolerance (OT) and aerobic power (AP) tests, before (PRE) and after HDBR (POST). A multilead scheme for TWA amplitude estimation was used, where non-normalized and T-wave amplitude normalized TWA indices were computed. In addition, spectral analysis of heart rate variability during OT was assessed. Both 5 d and 21 d HDBR induced a reduction in orthostatic tolerance time (OTT), as well as a decrease in maximal oxygen uptake and reserve capacity, thus suggesting cardiovascular deconditioning. However, TWA indices were found not to increase. Interestingly, subjects with lower OTT after 5 d HDBR also showed higher TWA during recovery after OT testing, associated with unbalanced sympathovagal response, even before the HDBR. In contrast with previous observations, augmented ventricular heterogeneity related to 5 d and 21 d HDBR was not sufficient to increase TWA under stress conditions.


Assuntos
Repouso em Cama , Eletrocardiografia , Estresse Fisiológico , Adulto , Aerobiose , Voluntários Saudáveis , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
16.
Nat Prod Rep ; 32(1): 29-48, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25315648

RESUMO

Covering: up to April 2014. The development of drugs with broad-spectrum antiviral activities is a long pursued goal in drug discovery. It has been shown that blocking co-opted host-factors abrogates the replication of many viruses, yet the development of such host-targeting drugs has been met with scepticism mainly due to toxicity issues and poor translation to in vivo models. With the advent of new and more powerful screening assays and prediction tools, the idea of a drug that can efficiently treat a wide range of viral infections by blocking specific host functions has re-bloomed. Here we critically review the state-of-the-art in broad-spectrum antiviral drug discovery. We discuss putative targets and treatment strategies, with particular focus on natural products as promising starting points for antiviral lead development.


Assuntos
Antivirais , Produtos Biológicos , Descoberta de Drogas , Produtos Biológicos/farmacologia , Sistemas de Liberação de Medicamentos , Humanos , Estrutura Molecular
19.
Int Rev Immunol ; 32(3): 282-306, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23617796

RESUMO

Infections with HIV represent a great challenge for the development of strategies for an effective cure. The spectrum of diseases associated with HIV ranges from opportunistic infections and cancers to systemic physiological disorders like encephalopathy and neurocognitive impairment. A major progress in controlling HIV infection has been achieved by highly active antiretroviral therapy (HAART). However, HAART does neither eliminate the virus reservoirs in form of latently infected cells nor does it completely reconstitute immune reactivity and physiological status. Furthermore, the failure of the STEP vaccine trial and the only marginal efficacies of the RV144 trial together suggest that the causal relationships between the complex sets of viral and immunological processes that contribute to protection or disease pathogenesis are still poorly understood. Here, we provide an up-to-date overview of HIV-host interactions at the cellular, the immune system and the neuroendocrine systems level. Only by integrating this multi-level knowledge one will be able to handle the systems complexity and develop new methodologies of analysis and prediction for a functional restoration of the immune system and the health of the infected host.


Assuntos
Vacinas contra a AIDS/uso terapêutico , Infecções por HIV/imunologia , Infecções por HIV/terapia , HIV-1 , Sistema Imunitário/imunologia , Sistemas Neurossecretores/imunologia , Animais , Terapia Antirretroviral de Alta Atividade , Comunicação Celular , Ensaios Clínicos como Assunto , Infecções por HIV/tratamento farmacológico , Humanos , Sistema Imunitário/virologia , Imunidade Celular , Sistemas Neurossecretores/virologia , Falha de Tratamento , Replicação Viral
20.
IEEE Trans Biomed Eng ; 59(8): 2312-20, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22692868

RESUMO

In this paper, we present a patient-adaptable algorithm for ECG heartbeat classification, based on a previously developed automatic classifier and a clustering algorithm. Both classifier and clustering algorithms include features from the RR interval series and morphology descriptors calculated from the wavelet transform. Integrating the decisions of both classifiers, the presented algorithm can work either automatically or with several degrees of assistance. The algorithm was comprehensively evaluated in several ECG databases for comparison purposes. Even in the fully automatic mode, the algorithm slightly improved the performance figures of the original automatic classifier; just with less than two manually annotated heartbeats (MAHB) per recording, the algorithm obtained a mean improvement for all databases of 6.9% in accuracy A, of 6.5% in global sensitivity S and of 8.9% in global positive predictive value P(+). An assistance of just 12 MAHB per recording resulted in a mean improvement of 13.1% in A, of 13.9% in S, and of 36.1% in P(+). For the assisted mode, the algorithm outperformed other state-of-the-art classifiers with less expert annotation effort. The results presented in this paper represent an improvement in the field of automatic and patient-adaptable heartbeats classification, concluding that the performance of an automatic classifier can be improved with an efficient handling of the expert assistance.


Assuntos
Algoritmos , Eletrocardiografia/métodos , Processamento de Sinais Assistido por Computador , Análise por Conglomerados , Bases de Dados Factuais , Frequência Cardíaca/fisiologia , Humanos , Sensibilidade e Especificidade
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