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1.
Anal Chem ; 96(21): 8291-8299, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38743800

RESUMO

Nanoparticles are produced at accelerating rates, are increasingly integrated into scientific and industrial applications, and are widely discharged into the environment. Analytical techniques are required to characterize parameters such as particle number concentrations, mass and size distributions, molecular and elemental compositions, and particle stability. This is not only relevant to investigate their utility for various industrial or medical applications and for controlling the manufacturing processes but also to assess toxicity and environmental fate. Different analytical strategies aim to characterize certain facets of particles but are difficult to combine to retrieve relevant parameters coherently and to provide a more comprehensive picture. In this work, we demonstrate the first online hyphenation of optofluidic force induction (OF2i) with Raman spectroscopy and inductively coupled plasma-time-of-flight-mass spectrometry (ICP-TOFMS) to harness their complementary technology-specific advantages and to promote comprehensive particle characterizations. We optically trapped individual particles on a weakly focused vortex laser beam by aligning a microfluidic flow antiparallelly to the laser propagation direction. The position of particles in this optical trap depended on the hydrodynamic diameter and therefore enabled size calibration as well as matrix elimination. Additionally, laser light scattered on particles was analyzed in a single particle (SP) Raman spectroscopy setup for the identification of particulate species and phases. Finally, particles were characterized regarding elemental composition and their distributions in mass and size using SP ICP-TOFMS. In a proof of concept, we analyzed polystyrene-based microplastic and TiO2 nanoparticles and demonstrated the opportunities provided through the coupling of OF2i with SP Raman and SP ICP-TOFMS.

2.
Anal Bioanal Chem ; 415(21): 5181-5191, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37392213

RESUMO

Manufacturers of nanoparticle-based products rely on detailed information about critical process parameters, such as particle size and size distributions, concentration, and material composition, which directly reflect the quality of the final product. These process parameters are often obtained using offline characterization techniques that cannot provide the temporal resolution to detect dynamic changes in particle ensembles during a production process. To overcome this deficiency, we have recently introduced Optofluidic Force Induction (OF2i) for optical real-time counting with single particle sensitivity and high throughput. In this paper, we apply OF2i to highly polydisperse and multi modal particle systems, where we also monitor evolutionary processes over large time scales. For oil-in-water emulsions we detect in real time the transition between high-pressure homogenization states. For silicon carbide nanoparticles, we exploit the dynamic OF2i measurement capabilities to introduce a novel process feedback parameter based on the dissociation of particle agglomerates. Our results demonstrate that OF2i provides a versatile workbench for process feedback in a wide range of applications.

3.
Medicina (Kaunas) ; 59(9)2023 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-37763795

RESUMO

Background and Objectives: Thermal skin injuries are a prevalent cause of skin damage, potentially leading to severe morbidity and significant mortality. In this study, we intended to estimate the effects of HBO (hyperbaric oxygen treatment) and antioxidant supplementation with Filipendula ulmaria extract, individually and simultaneously, in the treatment of thermal skin injuries. Materials and Methods: As a thermal skin injury experimental model, we used two-month-old male Wistar albino rats. Thermal injuries were made with a solid aluminium bar at a constant temperature of 75 °C for 15 s. Hyperbaric oxygen treatment was performed in a specially constructed hyperbaric chamber for rats (HYB-C 300) for seven consecutive days (100% O2 at 2.5 ATA for 60 min). Antioxidant supplementation was performed with oral administration of Filipendula ulmaria extract dissolved in tap water to reach a final concentration of 100 mg/kg b.w. for seven consecutive days. Results: Simultaneous administration of hyperbaric oxygen therapy and antioxidant supplementation with Filipendula ulmaria extract significantly ameliorated the macroscopic and histopathological characteristics of the wound area and healing. Also, this therapeutic approach decreased the local expression of genes for proinflammatory mediators and increased the expression of the µ-opioid receptor and the MT1 and MT2 receptors in the wound area and spinal cord, with a consequent increase in reaction times in behavioural testing. Conclusions: In conclusion, the presented results of our study allow evidence for the advantages of the simultaneous employment of HBO and antioxidant supplementation in the treatment of thermal skin injuries, with special reference to the attenuation of painful sensations accompanied by this type of trauma.


Assuntos
Queimaduras , Filipendula , Oxigenoterapia Hiperbárica , Masculino , Animais , Ratos , Ratos Wistar , Antioxidantes/uso terapêutico , Nociceptividade , Cicatrização , Oxigênio , Suplementos Nutricionais , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
4.
Br J Clin Pharmacol ; 88(8): 3887-3890, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35084053

RESUMO

Periprosthetic joint infection (PJI) after total knee arthroplasty remains a challenging complication. The treatment options for PJI include different procedures; however, regardless of the strategy, antibiotics are required. The combination of different antibiotics increased the rates of PJI eradication. For almost 3 decades, rifampicin has been used as part of antibiotic therapy for PJI. Drug fever, a febrile response that coincides with the onset of drug administration and disappears after drug discontinuation in the absence of other underlying conditions that could cause fever, is frequently misdiagnosed. We present the case of a 72-year-old man with PJI 6 months after total knee arthroplasty. Two-stage revision surgery was followed by culture-directed antibiotic treatment (ciprofloxacin and rifampicin) against Staphylococcus aureus isolated from the periprosthetic tissue. On the fifth day of antibiotic treatment, the patient became febrile and, in the next 5 days, he had an intermittent fever of up to 40°C, although he showed clinical improvement. The patient was normotensive without a maculopapular rash, urticaria or clotting abnormalities. A drug fever was suspected, and rifampicin was discontinued. A re-challenge test was performed, and the fever recurred. Antibiotic treatment with ciprofloxacin was continued and, after 12 months of follow-up, the patient was doing well. Clinicians should be aware that fever could be a clinical presentation of drug fever. If it occurs during an infection, drug fever could necessitate additional diagnostic procedures for further evaluation, inadequate antibiotic therapy and prolonged hospitalisation.


Assuntos
Infecções Relacionadas à Prótese , Idoso , Antibacterianos/efeitos adversos , Biofilmes , Ciprofloxacina/efeitos adversos , Humanos , Masculino , Infecções Relacionadas à Prótese/tratamento farmacológico , Estudos Retrospectivos , Rifampina/efeitos adversos
5.
Sci Rep ; 14(1): 222, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167619

RESUMO

Microvascular surgery, plastic and reconstructive hand surgery, and coronary artery bypass surgery call for a microanatomical study of the branching pattern of the superficial palmar arch (SPA). For the anatomical analysis, we used a group of 20 dissected human hands injected with 4% formaldehyde solution and a 10% mixture of melted gelatin and India ink. The morphometric study was performed on 40 human hands of adult persons injected with methyl-methacrylate fluid into the ulnar and radial arteries simultaneously and afterwards corroded in 40% KOH solution for the preparation of corrosion cast specimens. The mean diameter of the SPA, between the second and third common palmar digital arteries, was 1.86 ± 0.08 mm. We identified the persistent median artery (PMA) in 5% of hands. We distinguished the three main groups of the SPAs according to variations in morphology and branching of the arch: Type 1, the long SPA; Type 2, the middle length SPA; and Type 3, the short SPA found in 27.5% of specimens. The communicating branch (CB), a vessel interconnecting the SPA to the closest branch of the radial artery, is classified into two different morphological groups. The third type of incomplete short arterial arch is the most important of the three groups of SPAs. That short SPA is potentially inadequate for restoring circulation after occlusion or radial artery harvesting for coronary artery bypass.


Assuntos
Mãos , Artéria Ulnar , Adulto , Humanos , Cadáver , Mãos/anatomia & histologia , Artéria Radial , Ponte de Artéria Coronária
6.
Artigo em Inglês | MEDLINE | ID: mdl-35329183

RESUMO

Industry 4.0 introduces smart solutions throughout the company's supply chain, including manual assembly, where the goal is to ensure shorter work cycle time, increase productivity and quality, while minimizing costs. Following the principles of this paradigm, this paper proposes a digital transformation of the manual assembly process by implementing a multi-criterial algorithm (MCA) for adjusting and configuring a human-centered smart manual assembly workstation to ensure efficient and ergonomic performance of the manual assembly process. The MCA takes into account various influential parameters, such as the anthropometry of the individual worker, gender, complexity of the assembly process, product characteristics, and product structure. The efficiency of the MCA was verified both in the laboratory environment with the time analysis and in the virtual environment using Digital Human Modelling through several ergonomic analyses. The results of the implementation of the MCA on a manual assembly workstation support the digital (re)design of the manual assembly process with the aim of creating an efficient and ergonomically suitable workstation for each worker, thus increasing the productivity and efficiency of the human-centered manual assembly process.


Assuntos
Ergonomia , Indústrias , Algoritmos , Antropometria , Eficiência , Ergonomia/métodos , Humanos
7.
J Infect Dev Ctries ; 16(8): 1317-1322, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-36099375

RESUMO

INTRODUCTION: Tuberculosis (TB) continues to be a significant public health problem. The role of small non-coding RNAs, such as microRNAs (miRNAs), was investigated extensively in Mycobacterium tuberculosis (MTB) infection as well as in a variety of other pathophysiological processes in recent years. It was found that miRNAs act as regulators of both early reaction to MTB infection and in process of adaptation of the host immune cells during latent course of the disease. Molecule miRNA-146a is expressed exclusively in immune cells and it has the most prominent role in modulation of innate immunity. METHODOLOGY: We investigated the level of expression of miRNA-146a using an RT-qPCR technique in peripheral blood mononuclear cells of 44 patients with active pulmonary TB and 17 healthy individuals. We also analyzed the significance of miRNA-146a rs2910164 SNV for expression profile of miRNA-146a, in order to investigate potential usage of miRNA-146a as a biomarker for TB. RESULTS: There was statistically significant decrease of expression of miRNA-146a in TB group compared to control group. When gender cohorts were analyzed, the expression levels in TB male and TB female subgroup were significantly lower than the expression levels in the same gender control subgroups. CONCLUSIONS: Our results indicate that miRNA-146a plays a significant role in the pathogenesis of TB, suggesting that miRNA-146a could be used as a biomarker for active pulmonary TB.


Assuntos
MicroRNAs , Tuberculose Pulmonar , Tuberculose , Biomarcadores , Feminino , Humanos , Leucócitos Mononucleares , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Sérvia/epidemiologia , Tuberculose Pulmonar/genética
8.
Braz. J. Pharm. Sci. (Online) ; 58: e191062, 2022. graf
Artigo em Inglês | LILACS | ID: biblio-1394040

RESUMO

Abstract The aim of this study was to assess the effects of methanol extract of G. verum on redox status of isolated heart of spontaneously hypertensive rats after ischemia. Twenty-four Wistar albino rats were divided into three groups: untreated control rats and rats that received 125 and 250 mg/kg G. verum extract for 4 weeks per os. Index of lipid peroxidation (measured as TBARS) and parameters of antioxidative defence system such as level of reduced glutathione (GSH) and activities of catalase (CAT) and superoxide dismutase (SOD) were spectrophotometrically determined in heart homogenate. The index of lipid peroxidation in heart tissue was lower in both treated groups compared to the control group. On the other hand, the activity of SOD was significantly higher after consumption of both doses, while the activity of CAT was significantly higher only after treatment with a higher dose of extract. Based on our results we might conclude that 4-week treatment with methanol extracts of G. verum has the potential to modulate myocardial redox signaling after ischemia, thus significantly alleviating cardiac oxidative stress and exerting dose-dependent antioxidant properties. Future studies are certainly necessary to fully clarify the role of this plant species in myocardial I-R injury.


Assuntos
Animais , Masculino , Ratos , Ratos Endogâmicos SHR , Extratos Vegetais/efeitos adversos , Galium/efeitos adversos , Ferimentos e Lesões/classificação , Estresse Oxidativo/imunologia , Coração , Isquemia/patologia , Antioxidantes/efeitos adversos
9.
Int J Inj Contr Saf Promot ; 21(4): 313-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23998250

RESUMO

The objective of this study is to describe severe road traffic injuries (RTIs) in the population under 18 years in Belgrade, the capital of Serbia. We analysed both severe non-fatal and fatal RTIs in children and adolescents under 18 years old in the Belgrade area, during the period 2008-2011. Data sources were the official statistics of the Public Health Institute in Belgrade and forensic-medical records from two paediatric university hospitals and five university hospitals for adults. Using descriptive statistical methods, demographic characteristics, mechanism, type and time of injuries, surgical treatment procedures, injury severity scores (ISS), length of stay and outcome were evaluated. The admission and mortality rates were calculated. Among the total of 379 injured, 256 (67.5%) were male; the average age was 13.0 ± 4.7 (range: 0-18 years). The annual hospital admission rate of RTIs for both sexes decreased in average by 12.6% (95% CI = 9.3%-15.9%). The mean percentage of annual changes of mortality rates was 2.0 %; 95% CI = 1.3%-5.3% (5.7 per 100,000 in 2008, 5.6 in 2009, 4.7 in 2010 and 5.9 in 2011). The highest admission rates and mortality rates were for pedestrians, followed by passengers and cyclists. Accidents occurred most commonly on Monday (18.7%). Among children hospitalised for traffic injuries, 57.8% had head and neck trauma, 30.6% extremity fractures, 5% abdominal injuries, 4.2% chest and 2.4% multiple injuries. The average ISS was 22.4 (SD = 20.4), ranging from 1 to 75. Alcohol in blood was confirmed in 7.4% males and 3.3% females (p > 0.05). The average time of hospital stay was 8.8 days (SD = 16.7), ranging from 1 to 14. The increased rates require implementation of a well-defined national strategy in our country.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Ferimentos e Lesões/epidemiologia , Acidentes de Trânsito/mortalidade , Adolescente , Fatores Etários , Criança , Pré-Escolar , Cidades/estatística & dados numéricos , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Escala de Gravidade do Ferimento , Masculino , Sérvia/epidemiologia , Ferimentos e Lesões/etiologia , Ferimentos e Lesões/mortalidade
10.
Srp Arh Celok Lek ; 141(11-12): 789-93, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24502099

RESUMO

INTRODUCTION: Occupational exposure to blood and body fluids is a serious concern of health care workers and presents a major risk of transmission of infections such as human immuno-deficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV). OBJECTIVE: The aim of this study was to determine the frequency and circumstances of occupational blood and body fluid exposures among health care workers. METHODS: Cross-sectional study was conducted in three university hospitals in Belgrade. Anonymous questionnaire was used containing data about demographic characteristics, self-reported blood and body fluid exposures and circumstances of percutaneous injuries. RESULTS: Questionnaire was filled in and returned by 216 health care workers (78.2% of nurses and 21.8% of doctors). 60.6% of participants-health care workers had sustained at least one needlestick injury during their professional practice; 25.9% of them in the last 12 months. Of occupational groups, nurses had higher risk to experience needlestick injuries than doctors (p = 0.05). The majority of the exposures occurred in the operating theatre (p = 0.001). Among factors contributing to the occurrence of needlestick injuries, recapping needles (p = 0.003) and decontamination/cleaning instruments after surgery (p = 0.001) were more frequent among nurses, while use of a needle before intervention was common among doctors (p = 0.004). Only 41.2% of health care workers had reported their injuries to a supervisor in order to obtain medical attention. 50.2% of health care workers were vaccinated with three doses of hepatitis B vaccine. CONCLUSION: There is a high rate of needlestick injuries in the daily hospital routine. Implementation of safety devices would lead to improvement in health and safety of medical staff.


Assuntos
Sangue , Líquidos Corporais , Pessoal de Saúde , Hospitais Universitários , Transmissão de Doença Infecciosa do Paciente para o Profissional , Ferimentos Penetrantes Produzidos por Agulha/epidemiologia , Exposição Ocupacional/estatística & dados numéricos , Adulto , Estudos Transversais , Feminino , Infecções por HIV/transmissão , Hepatite B/prevenção & controle , Hepatite B/transmissão , Vacinas contra Hepatite B/uso terapêutico , Hepatite C/transmissão , Humanos , Masculino , Pessoa de Meia-Idade , Enfermeiras e Enfermeiros , Médicos , Risco , Sérvia/epidemiologia , Inquéritos e Questionários
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