RESUMO

This study reports on the modification of bacterial cellulose (BC) membranes produced by static fermentation of Komagataeibacter xylinus bacterial strains with graphene oxide-silver nanoparticles (GO-Ag) to yield skin wound dressings with improved antibacterial properties. The GO-Ag sheets were synthesized through chemical reduction with sodium citrate and were utilized to functionalize the BC membranes (BC/GO-Ag). The BC/GO-Ag composites were characterized to determine their surface charge, morphology, exudate absorption, antimicrobial activity, and cytotoxicity by using fibroblast cells. The antimicrobial activity of the wound dressings was assessed against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The results indicate that the BC/GO-Ag dressings can inhibit ∼70% of E. coli cells. Our findings also revealed that the porous BC/GO-Ag antimicrobial dressings can efficiently retain 94% of exudate absorption after exposure to simulated body fluid (SBF) for 24 h. These results suggest that the dressings could absorb excess exudate from the wound during clinical application, maintaining adequate moisture, and promoting the proliferation of epithelial cells. The BC/GO-Ag hybrid materials exhibited excellent mechanical flexibility and low cytotoxicity to fibroblast cells, making excellent wound dressings able to control bacterial infectious processes and promote the fast healing of dermal lesions.

Assuntos

Antibacterianos , Materiais Biocompatíveis , Celulose , Escherichia coli , Grafite , Teste de Materiais , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Prata , Staphylococcus aureus , Cicatrização , Grafite/química , Grafite/farmacologia , Prata/química , Prata/farmacologia , Cicatrização/efeitos dos fármacos , Celulose/química , Celulose/farmacologia , Nanopartículas Metálicas/química , Antibacterianos/química , Antibacterianos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Tamanho da Partícula , Pseudomonas aeruginosa/efeitos dos fármacos , Gluconacetobacter xylinus/química , Humanos , Camundongos , Bandagens , Animais

RESUMO

Bacterial cellulose (BC), produced by bacterial fermentation, is a high-purity material. BC can be oxidized (BCOXI), providing aldehyde groups for covalent bonds with drugs. Frutalin (FTL) is a lectin capable of modulating cell proliferation and remodeling, which accelerates wound healing. This study aimed to develop an FTL-incorporated dressing based on BC, and to evaluate its physicochemical properties and biological activity in vitro. An experimental design was employed to maximize FTL loading yield onto the BC and BCOXI, where independent variables were FTL concentration, temperature and immobilization time. BCOXI-FTL 1 (44.96 % ± 1.34) had the highest incorporation yield (IY) at the experimental conditions: 6 h, 5 °C, 20 µg mL-1. The second highest yield was BCOXI-FTL 6 (23.28 % ± 1.43) using 24 h, 5 °C, 100 µg mL-1. Similarly, the same reaction parameters provided higher immobilization yields for native bacterial cellulose: BC-FTL 6 (16.91 % ± 1.05) and BC-FTL 1 (21.71 % ± 1.57). Purified FTL displayed no cytotoxicity to fibroblast cells (<50 µg mL-1 concentration) during 24 h. Furthermore, BCOXI-FTL and BC-FTL were non-cytotoxic during 24 h and stimulated fibroblast migration. BCOXI-FTL demonstrated neutrophil activation in vitro similar to FTL. These promising results indicate that the bacterial cellulose matrices containing FTL at low concentrations, could be used as an innovative biomaterial for developing wound dressings.

Assuntos

Artocarpus , Bandagens , Celulose , Lectinas de Plantas , Artocarpus/química , Celulose/química , Celulose/farmacologia , Lectinas de Plantas/química , Lectinas de Plantas/farmacologia , Animais , Camundongos , Fibroblastos/efeitos dos fármacos , Cicatrização/efeitos dos fármacos

RESUMO

BACKGROUND: Fatigue is one of the most common symptoms reported by individuals with multiple sclerosis and it contributes to the reduction of the functionality. Therefore, it is important to assess the impact of fatigue on daily living of individuals with multiple sclerosis. The Modified Fatigue Impact Scale (MFIS) is an instrument to assess the perception of the impact of fatigue. However, there have been no investigations about the measurement properties of this instrument administered over the telephone for individuals with multiple sclerosis. OBJECTIVES: To verify the concurrent validity, the test-retest reliability, the standard error of measurement (SEM) and the minimal detectable change (MDC) of the MFIS applied over the telephone to assess the perception of the impact of fatigue of individuals with multiple sclerosis. METHODS: The MFIS, composed of 21 items covering three domains: physical, cognitive and psychosocial, was applied at three different moments with an interval of 5-7 days. To establish the concurrent criterion validity, the face-to-face application and the first evaluation by telephone were used. The two telephone assessments were used to assess the test-retest reliability The intraclass correlation coefficient (ICC) with 95 % confidence interval (CI) and the Bland-Altman method were used. The standard error of measurement (SEM) and the MDC was calculated according to reliability results. RESULTS: Thirty individuals (40.83 ± 10.61, 60 % female) were included. The median score on the Expanded Disability Status Scale was 2.00 (±4.00). The majority of participants experienced fatigue (n = 17; 56.67 %). A significant and high magnitude correlation (0.70 ≤ ICC ≤ 0.87, p < 0.001) was found in the investigation of concurrent criterion validity. The Bland-Altman method showed a mean difference between 0.70 to 2.17 points between face-to-face and telephone-based application of the MFIS. For test-retest reliability, a significant and very high magnitude correlation (0.91 ≤ ICC ≤ 0.97, p < 0.001) was found. The Bland-Altman method showed a mean difference between -0.03 and -0.77 points between two telephone-based applications. The SEM and the MDC were 0.71 and 1.97 points. CONCLUSION: The telephone-based application of the MFIS to assess the perceived impact of fatigue in individuals with multiple sclerosis demonstrated adequate measurement properties, and may be a valuable tool to assess patients in clinical practice.

Assuntos

Fadiga , Esclerose Múltipla , Telefone , Humanos , Fadiga/etiologia , Fadiga/diagnóstico , Feminino , Reprodutibilidade dos Testes , Masculino , Esclerose Múltipla/complicações , Adulto , Pessoa de Meia-Idade , Psicometria/normas , Índice de Gravidade de Doença

RESUMO

Bacterial cellulose (BC) represents a promising biomaterial, due to its unique and versatile properties. We report, herein, on purposely-designed structural modifications of BC that enhance its application as a wound dressing material. Chemical modification of the functional groups of BC was performed initially to introduce a hydrophobic/oleophilic character to its surface. Specifically, silanization was carried out in an aqueous medium using methyltrimethoxisilane (MTMS) as the silanizing agent, and aerogels were subsequently prepared by freeze-drying. The BC-MTMS aerogel obtained displayed a highly porous (99 %) and lightweight structure with an oil absorption capacity of up to 52 times its dry weight. The XRD pattern indicated that the characteristic crystallographic planes of the native BC were maintained after the silanization process. Thermal analysis showed that the thermal stability of the BC-MTMS aerogel increased, as compared to the pure BC aerogel (pBC). Moreover, the BC-MTMS aerogel was not cytotoxic to fibroblasts and keratinocytes. In the second step of the study, the incorporation of natural oils into the aerogel's matrix was found to endow antimicrobial and/or healing properties to BC-MTMS. Bourbon geranium (Pelargonium X ssp.) essential oil (GEO) was the only oil that exhibited antimicrobial activity against the tested microorganisms, whereas buriti (Mauritia flexuosa) vegetable oil (BVO) was non-cytotoxic to the cells. This study demonstrates that the characteristics of the BC structure can be modified, while preserving its intrinsic features, offering new possibilities for the development of BC-derived materials for specific applications in the biomedical field.

Assuntos

Celulose , Óleos Voláteis , Óleos de Plantas , Celulose/química , Celulose/farmacologia , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Géis/química , Cicatrização/efeitos dos fármacos , Fabaceae/química , Humanos , Fibroblastos/efeitos dos fármacos , Pelargonium/química , Silanos/química

RESUMO

The solvent-free esterification of the free fatty acids (FFAs) obtained by the hydrolysis of castor oil (a non-edible vegetable oil) with 2-ethyl-1-hexanol (a branched fatty alcohol) was catalyzed by different free lipases. Eversa Transform 2.0 (ETL) features surpassed most commercial lipases. Some process parameters were optimized by the Taguchi method (L16'). As a result, a conversion over 95% of the FFAs of castor oil into esters with lubricants properties was achieved under optimized reaction conditions (15 wt% of biocatalyst content, 1:4 molar ratio (FFAs/alcohol), 30 °C, 180 rpm, 96 h). The substrates molar ratio had the highest influence on the dependent variable (conversion at 24 h). FFAs/2-ethyl-1-hexanol esters were characterized regarding the physicochemical and tribological properties. Interestingly, the modification of the FFAs with 2-ethyl-1-hexanol by ETL increased the oxidative stability of the FFAs feedstock from 0.18 h to 16.83 h. The biolubricants presented a lower friction coefficient than the reference commercial mineral lubricant (0.052 ± 0.07 against 0.078 ± 0.04). Under these conditions, ETL catalyzed the oligomerization of ricinoleic acid (a hydroxyl fatty acid) into estolides, reaching a conversion of 25.15% of the initial FFAs (for the first time).

Assuntos

Óleo de Rícino , Ácidos Graxos não Esterificados , Hexanóis , Esterificação , Ésteres/química , Ácidos Graxos/química , Lipase/metabolismo , Etanol , Catálise , Enzimas Imobilizadas/química

RESUMO

BACKGROUND: Approximately 80% of infected women infected by Chlamydia trachomatis are asymptomatic, although this infection can lead to serious complications in the female reproductive tract. Few data on Chlamydia infection and genotypes are available in Amazonian communities. OBJECTIVES: To describe the prevalence of and associated factors and to identify the genotypes of sexual C. trachomatis infection in female university students in different urban centers (capital and interiors) in the Brazilian state of Pará, in the eastern Amazon region. METHODS: A cross-sectional study was performed among young women attending public universities in four different urban centers in the eastern Amazon region. They were invited to participate in the studt and cervical secretions were collected for molecular diagnosis of C. trachomatis. We utilized amplification of the ompA gene by nested PCR. Positive samples were genotyped by nucleotide sequencing. Study participants completed a questionnaire on social, epidemiological, and reproductive health variables. A Qui-square and Binominal regression test were used to evaluate the degree of association of these variables with the infection. RESULTS: A total of 686 female students was included in the study. The overall prevalence of C. trachomatis was 11.2% (77/686). The prevalence of this infection was higher in interiors (15.2% vs 9.5%/ p: 0.0443). Female university students who do not have a sexual partner (11.8%/p <0.008), who do not use a condom in their sexual relations (17.8%/p <0.0001) and who reported having suffered a miscarriage (32%/p <0.0001) have high chances of acquiring this sexual infection. The ompA gene was sequenced in only 33 (42.8%) samples, revealing the genotype J was the most frequent (27.2% [9/33]), followed by genotypes D (24.2% [8/33]), and then genotypes F (18.2% [6/33]), E (15.1% [5/33]) K (6.1% [2/33]), Ia (6.1% [2/33]), and G (3.1% [1/33]). CONCLUSIONS: The high prevalence of sexual infection by C. trachomatis in the female university students from the interior of the state of Pará, individuals with no fixed sexual partner, those that had had a miscarriage, the students that do not use condoms in their sexual relations. The genotype J of C. trachomatis genotypes was the most frequent. These data are important to help defining the epidemiological effects of chlamydial infections in Amazonian populations.

Assuntos

Aborto Espontâneo , Infecções por Chlamydia , Gravidez , Humanos , Feminino , Chlamydia trachomatis/genética , Universidades , Prevalência , Cidades/epidemiologia , Brasil/epidemiologia , Estudos Transversais , Infecções por Chlamydia/epidemiologia , Infecções por Chlamydia/diagnóstico , Genótipo

RESUMO

This study investigated the prevalence and the potential risk factors for anxiety and depression among physiotherapists during the pandemic. Physiotherapists answered a web-based questionnaire including 1) sociodemographic, professional and clinical information; 2) psychosocial demands; and 3) two validated questionnaires to measure anxiety and depression. Binary logistic regression identified the risk factors by means of odds ratio (OR) and 95% confidence interval (CI). In 417 participants, there was a high prevalence of anxiety (48.2%) and depression (53.0%). The risk factors for anxiety were female sex (OR 2.07; 95%CI 1.01-4.24), worsening in sleep patterns (OR 3.78; 95%CI 1.92-7.44), moderate (OR 2.24; 95%CI 1.00-5.00) and extreme concern about financial issues (OR 3.47; 95%CI 1.57-7.65), and extreme loneliness (OR 3.47; 95%CI 1.71-7.07). The risk factors for depression were female sex (OR 2.16; 95%CI 1.03-4.55), low family income (OR 2.43; 95%CI 1.21-4.89), worsening in sleep patterns (OR 5.97; 95%CI 3.02-11.82), extreme concern about financial issues (OR 2.61; 95%CI 1.15-5.94), and extreme loneliness (OR 4.38; 95%CI 2.00-9.63). This study found a high prevalence of anxiety and depression in the studied population and identified risk factors for both.

Assuntos

COVID-19 , Fisioterapeutas , Humanos , Feminino , Masculino , Estudos Transversais , Pandemias , Brasil/epidemiologia , Depressão/epidemiologia , COVID-19/epidemiologia , Ansiedade/epidemiologia

RESUMO

Abstract This study investigated the prevalence and the potential risk factors for anxiety and depression among physiotherapists during the pandemic. Physiotherapists answered a web-based questionnaire including 1) sociodemographic, professional and clinical information; 2) psychosocial demands; and 3) two validated questionnaires to measure anxiety and depression. Binary logistic regression identified the risk factors by means of odds ratio (OR) and 95% confidence interval (CI). In 417 participants, there was a high prevalence of anxiety (48.2%) and depression (53.0%). The risk factors for anxiety were female sex (OR 2.07; 95%CI 1.01-4.24), worsening in sleep patterns (OR 3.78; 95%CI 1.92-7.44), moderate (OR 2.24; 95%CI 1.00-5.00) and extreme concern about financial issues (OR 3.47; 95%CI 1.57-7.65), and extreme loneliness (OR 3.47; 95%CI 1.71-7.07). The risk factors for depression were female sex (OR 2.16; 95%CI 1.03-4.55), low family income (OR 2.43; 95%CI 1.21-4.89), worsening in sleep patterns (OR 5.97; 95%CI 3.02-11.82), extreme concern about financial issues (OR 2.61; 95%CI 1.15-5.94), and extreme loneliness (OR 4.38; 95%CI 2.00-9.63). This study found a high prevalence of anxiety and depression in the studied population and identified risk factors for both.

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Resumo Este estudo investigou a prevalência e potenciais fatores de risco para ansiedade e depressão em fisioterapeutas durante a pandemia. Fisioterapeutas responderam a um questionário na web, incluindo: dados sociodemográficos, profissionais e clínicos; demandas psicossociais; e dois questionários validados para medir ansiedade e depressão. Regressão logística binária identificou fatores de risco para ansiedade e depressão por meio de odds ratio (OR) e intervalo de confiança de 95% (IC). Em 417 participantes houve alta prevalência de ansiedade (48,2%) e depressão (53%). Os fatores de risco para ansiedade foram: sexo feminino (OR 2,07; IC95% 1,01-4,24), piora nos padrões de sono (OR 3,78; IC95% 1,92-7,44), moderada (OR 2,24; IC95% 1,00-5,00) e extrema preocupação financeira (OR 3,47; IC95% 1,57-7,65) e extrema solidão (OR 3,47; IC95% 1,71-7,07). Os fatores de risco para depressão foram: sexo feminino (OR 2,16; IC95% 1,03-4,55), baixa renda familiar (OR 2,43; IC95% 1,21-4,89), piora nos padrões de sono (OR 5,97; IC95% 3,02-11,82), extrema preocupação financeira (OR 2,61; IC95% 1,15-5,94) e extrema solidão (OR 4,38; IC95% 2,00-9,63). Este estudo mostrou alta prevalência de ansiedade e depressão na população estudada e identificou fatores de risco para ambos.

RESUMO

OBJECTIVE: Oral candidiasis is a common fungal infection that affects the oral mucosa, and happens when Candida albicans interacts with bacteria in the oral microbiota, such as Streptococcus mutans, causing severe early childhood caries. C. albicans and S. mutans mixed biofilms are challenging to treat with conventional antimicrobial therapies, thus, new anti-infective drugs are required. This study aimed to test a drug delivery system based on chitosan microparticles loaded with geranium and lemongrass essential oils to inhibit C. albicans and S. mutans mixed biofilms. METHODOLOGY: Chitosan microparticles loaded with essential oils (CM-EOs) were obtained by spray-drying. Susceptibility of planktonic were performed according CLSI at 4 to 2,048 µg/mL. Mixed biofilms were incubated at 37ºC for 48 h and exposed to CM-EOs at 256 to 4,096 µg/mL. The antimicrobial effect was evaluated using the MTT assay, with biofilm architectural changes analyzed by scanning electron microscopy. RAW 264.7 cell was used to evaluate compound cytotoxicity. RESULTS: CM-EOs had better planktonic activity against C. albicans than S. mutans. All samples reduced the metabolic activity of mixed C. albicans and S. mutans biofilms, with encapsulated oils showing better activity than raw chitosan or oils. The microparticles reduced the biofilm on the slides. The essential oils showed cytotoxic effects against RAW 264.7 cells, but encapsulation into chitosan microparticles decreased their toxicity. CONCLUSION: This study demonstrates that chitosan loaded with essential oils may provide an alternative method for treating diseases caused by C. albicans and S. mutans mixed biofilm, such as dental caries.

Assuntos

Quitosana , Cárie Dentária , Óleos Voláteis , Pré-Escolar , Humanos , Óleos Voláteis/farmacologia , Candida albicans , Streptococcus mutans , Quitosana/farmacologia , Cárie Dentária/prevenção & controle , Biofilmes

RESUMO

The increasing worries by the inadequate use of energy and the preservation of nature are promoting an increasing interest in the production of biolubricants. After discussing the necessity of producing biolubricants, this review focuses on the production of these interesting molecules through the use of lipases, discussing the different possibilities (esterification of free fatty acids, hydroesterification or transesterification of oils and fats, transesterification of biodiesel with more adequate alcohols, estolides production, modification of fatty acids). The utilization of discarded substrates has special interest due to the double positive ecological impact (e.g., oil distillated, overused oils). Pros and cons of all these possibilities, together with general considerations to optimize the different processes will be outlined. Some possibilities to overcome some of the problems detected in the production of these interesting compounds will be also discussed.

Assuntos

Lipase , Óleos , Lipase/metabolismo , Esterificação , Álcoois , Biocatálise , Biocombustíveis , Enzimas Imobilizadas/metabolismo