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1.
J Community Health ; 45(4): 689-695, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32468155

RESUMO

The psychological impact of outbreaks on individuals includes an intense and wide range of psychiatric morbidities. People are likely to experience feelings as; worry about being infected or getting sick, increased self-blame, and helplessness. This study aimed to assess the impact of COVID-19 on mental health and social support among Egyptian adults during the period of the pandemic. This is a cross-sectional observational study using an anonymous online questionnaire. The survey was conducted through a link shared on social networking sites. It was conducted from 2 May 2020 to 9 May 2020. The general populations of the Egyptian adults were included by using convenience and snowball sampling technique (510 adults). Impact Event scale mean 34.3 ± 15. About 211 (41.4%) suffered a severe impact. There was an increase in stress from work in 174 (34.1%), financial stress in 284 (55.7%), and stress from home in 320 (62.7%). Half of them felt horrified and helpless in 275 (53.9%), and 265 (52%) respectively, while 338 (66.3%) felt apprehensive. only 24.2% reported increased support from friends, while increased support from family members in 207 (40.6%). 46.5% shared their feelings with family members, while 176 (34.5%) shared with others. Caring for family members' feelings increased in 330 (64.7%). Age and rural residency were negative predictors for the impact of event score, while female gender or presence of chronic condition was a positive predictor for the impact of event score. Covid-19 pandemic has a great psychological impact on adult Egyptians and affected social support.


Assuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/psicologia , Saúde Mental/estatística & dados numéricos , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/psicologia , Apoio Social , Adolescente , Adulto , Ansiedade/epidemiologia , COVID-19 , Estudos Transversais , Egito/epidemiologia , Emoções , Família/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Psicológico/epidemiologia , Inquéritos e Questionários , Adulto Jovem
2.
BMC Med Ethics ; 21(1): 49, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32539704

RESUMO

BACKGROUND: Organ donation has become one of the most effective ways to save lives and improve the quality of life for patients with end-stage organ failure. No previous studies have investigated the preferences for the different consenting options for organ donation in Egypt. This study aims to assess Egyptians' preferences regarding consenting options for posthumous organ donation, and measure their awareness and acceptance of the Egyptian law articles regulating organ donation. METHODS: A cross sectional study was conducted among 2743 participants over two years. Each participant was required to rank eleven consenting options from 1 (most preferred) to 11 (least preferred), and to report his awareness and acceptance of the seven articles of the Egyptian law of organ donation. RESULTS: 47% of the participants expressed willingness to donate their organs after death. This percentage increased to 78% when consenting options were explained to participants. "Informed consent by donor only" was the most preferred type of consent for one third of respondents. Awareness of the law articles regulating organ donation was relatively low ranging from 56% to 23%. CONCLUSION: Currently, around half of the Egyptian population agree to posthumous organ donation. This percentage could be increased significantly by raising the awareness about how the process of donation could be regulated and how the patient's right of decision could be protected.


Assuntos
Distância Psicológica , Obtenção de Tecidos e Órgãos , Estudos Transversais , Egito , Humanos , Qualidade de Vida , Doadores de Tecidos
3.
East Mediterr Health J ; 24(6): 579-587, 2018 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-30079953

RESUMO

BACKGROUND: Attention deficit hyperactivity disorder (ADHD) is a common paediatric neurodevelopmental disorder, with serious impacts on individuals, families and communities. It is associated with cognitive, behavioural, emotional, social and developmental disturbances and impaired academic achievement. AIMS: To describe quality of life (QOL) of parents of ADHD children and family function. To determine the relationship between QOL, family function and sociodemographic characteristics. METHODS: This was a cross-sectional study of 125 parents of children with any type of ADHD who were selected by systematic random sampling. The study was conducted between May and December 2015 in the Outpatient Family Medicine Clinic at Suez Canal University Hospital. The World Health Organization Quality of Life-Brief (WHOQOL-BREF) and Adaptability, Participation, Growth, Affection, Resolution (APGAR) questionnaires were used for data collection. RESULTS: Median physical, psychological and social domain scores were 12, and mean environmental domain score was 11.9. The median scores of perception of health and QOL of the parents were 3.0. Most of the families (79.2%) were dysfunctional. Statistically significant relationships were found between all domains and education; physical scores of QOL and gender, employment and income; psychological scores of QOL and residence; environmental scores of QOL and age, income and marital status. Dysfunctional families were likely to be affected by age, gender, physical and psychological domain scores of QOL of parents. CONCLUSIONS: Parents of children with ADHD had average QOL. Most parents had dysfunctional families. Future family intervention studies are recommended.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Família/psicologia , Pais/psicologia , Qualidade de Vida/psicologia , Adulto , Criança , Estudos Transversais , Egito , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto Jovem
4.
J Family Community Med ; 31(1): 16-24, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38406223

RESUMO

BACKGROUND: Health coaching effectively improves hypertension self-care activities and the control of blood pressure (BP) in hypertensive patients. Studies on the effects of health coaching on patients in primary care with uncontrolled hypertension in developing countries are limited. In this study, the effectiveness of health coaching on hypertension self-care and BP control was assessed in patients who have uncontrolled hypertension compared to standard care in Egypt. MATERIALS AND METHODS: Our quasi-experimental study included control and intervention groups. The intervention group included 70 participants who received health coaching sessions (face-to-face and by telephone) besides the standard care, whereas the control group included 71 participants who only received the standard care. The study was conducted between July 2020 and November 2021. The participants were recruited from three primary healthcare settings in the Port Said Governorate. Personal and medical history, BP measurements, and hypertension self-care activity level effects (H-SCALE) were obtained. Paired-t-test was used to assess the changes in BP measurement, and H-SCALE score before and after receiving the health coaching. McNemar's test was used to assess changes in controlled BP and optimal hypertension self-care activities between control and health coached groups. Multiple logistic regression analysis assessed the predictors of better BP control. RESULTS: Health coaching resulted in more controlled BP (51.4%, P < 0.001) compared to the delivery of only usual care (11.3%, P = 0.008). The intervention showed a significant promotion in hypertension self-care activities, including medication usage (P < 0.001), low-salt diet (P < 0.001), and weight management (P < 0.001). The H-SCALE score mean change was the only predictor for BP control (odds ratio 1.057, P = 0.048) in the intervention group after 6 months. CONCLUSION: Intervention including traditional health coaching and phone calls is a beneficial modality for the promotion of hypertension self-care and improvement of BP control in primary care patients with uncontrolled hypertension.

5.
Int J Biol Macromol ; 241: 124632, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37119918

RESUMO

The limited usage of chitosan as a dye adsorbent is attributed to its compact structure and low swelling ability, despite its exceptional properties. The present study aimed to prepare novel chitosan/pyrazole Schiff base (ChS) adsorbents enriched with greenly synthesized zinc oxide nanoparticles. The preparation of ZnO-NPs was carried out through a green approach using the Coriandrum sativum extract. The presence of ZnO-NPs at the nanoscale was validated through TEM, DLS and XRD analyses. FTIR and 1H NMR confirmed the successful preparation of the Schiff base and its ZnO-NPs adsorbents. The incorporation of ZnO-NPs improved the thermal, swelling and antimicrobial properties of the chitosan Schiff base. In addition, a significant improvement in the adsorption of Maxilon Blue dye from its aqueous solution by the Schiff base/ZnO-NPs adsorbent was achived. The prepared ChS/ZnO-NPs adsorbent has the potential to be used as an alternative to conventional adsorbents for the removal of dyes from wastewater.


Assuntos
Quitosana , Nanopartículas , Óxido de Zinco , Corantes/química , Quitosana/química , Óxido de Zinco/química , Águas Residuárias , Bases de Schiff , Nanopartículas/química
6.
Pan Afr Med J ; 45: 85, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37663634

RESUMO

Introduction: the global prevalence of type 2 diabetes in adults is estimated to be 6.4%. The current prevalence of type 2 diabetes in Egyptians aged 20 to 79 is approximately 15.6%. The objective of medical nutrition therapy (MNT) is to optimize the management of the "ABC" for diabetes control, glycated hemoglobin, blood pressure, and cholesterol. Our study aimed to assess the effect of MNT on glycemic control in patients with type 2 diabetes attending the family practice clinic. Methods: a quasi-experimental intervention trial was conducted with 40 diabetic patients seeking medical service in the Suez Canal University Hospital family practice clinic. The participants were over 20 years old and had uncontrolled type 2 diabetes. Patients were surveyed using El-Gilany questionnaire to evaluate the socio-demographic traits, physical examination data, and laboratory investigations at baseline and after 12 weeks. Results: medical nutrition therapy (MNT) significantly reduced glycated hemoglobin level (p<0.001); the median level of glycated hemoglobin was 10% with a minimum level of 7.5% vs. a maximum of 14% in the pre-intervention phase. In comparison, the median glycated hemoglobin level was 9.5%, with a minimum level of 5.6% vs. a maximum of 13.5% in the post-intervention phase. In addition, there was a significant improvement in blood pressure, weight, body mass index, fasting plasma glucose, and lipid profile. Conclusion: there is evidence that MNT is a crucial component of type 2 diabetes therapy.


Assuntos
Diabetes Mellitus Tipo 2 , Terapia Nutricional , Adulto , Humanos , Adulto Jovem , Instituições de Assistência Ambulatorial , Diabetes Mellitus Tipo 2/terapia , Hemoglobinas Glicadas , Controle Glicêmico
7.
Int J Biol Macromol ; 212: 294-302, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35605720

RESUMO

Despite the outstanding characteristics of alginate, it suffers from bad UV-barrier, water barrier, and antimicrobial properties limiting its wide usage in food packaging. For this concern, Box-Behnken design (BBD) was applied to prepare an alginate-based edible coating of the best optimized UV-shielding properties upon the incorporation of both Aloe vera (AV) and zinc oxide nanoparticles (ZnO-NPs). The optimized minimum UV-transmittance was 4.96% when the optimized compositions of alginate (1.05 g), AV (2.95 g), and ZnO-NPs (4.93 wt%) were used. FTIR was used to verify the successful edible coating preparation while the wide-angle X-ray diffraction (XRD) was used to identify the interactions between the film's components. The incorporation of both AV and ZnO-NPs significantly improved alginate's thermal, water vapor permeability (WVP), mechanical and antimicrobial properties. In addition, the films incorporated with both AV and ZnO-NPs exhibited excellent UV-barrier properties compared with neat alginate. The optimized alginate film incorporated with both ZnO-NPs and AV significantly extended the shelf-life of tomato fruits up to 16 days without any defects. Due to the outstanding physical, UV-shielding, and antimicrobial properties of the optimized alginate/AV/ZnO-NPs film, it could be used potentially in food packaging industries.


Assuntos
Aloe , Anti-Infecciosos , Filmes Comestíveis , Óxido de Zinco , Alginatos , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Embalagem de Alimentos
8.
Int J Biol Macromol ; 190: 837-844, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34517032

RESUMO

The applications of edible coatings stemmed exclusively from alginate in food packaging are restricted due to their inherent deficient antimicrobial, barrier, and UV-barrier properties. In this work, we aimed to design smart alginate-based coatings for active food packaging through the addition of both aloe vera (AV) and garlic oil (GO). The interactions between the film components were verified by FTIR and XRD. Thermal and mechanical properties were improved by the presence of AV and GO. The presence of AV and GO did not significantly influence the transparency of alginate films. The films exhibited a significant UV-shielding to all UV regions. Water vapor permeability was significantly (p < 0.05) reduced either through the incorporation of AV or GO. The antimicrobial properties of the prepared films were considerably improved by the presence of AV and GO. The shelf-life of tomatoes (Solanum lycopersicum L.) was extended when coated with the alginate film incorporated with AV and GO. Owing to the outstanding UV-shielding, mechanical, thermal, and antimicrobial properties, the alginate/AV/GO active coatings could potentially be implemented in the food packaging industry.


Assuntos
Alginatos/química , Filmes Comestíveis , Embalagem de Alimentos , Aloe/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Cor , Fungos/efeitos dos fármacos , Alho/química , Testes de Sensibilidade Microbiana , Permeabilidade , Óleos de Plantas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor , Termogravimetria , Raios Ultravioleta , Difração de Raios X
9.
PLoS One ; 16(6): e0252996, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34125842

RESUMO

BACKGROUND: Informed consent (IC) is a healthcare standard emphasizing the meaning of human dignity as clarified in the Universal Declaration of Human Rights. Data about IC practices in Egypt is insufficient. This study aimed to assess the Egyptian patients'/guardians' experiences about IC and their expectations about its practices' purposes in general and according to the type of the healthcare facility. METHODS: Self-administered questionnaire was carried out for 1092 participants who had undergone or were scheduled to a procedure requiring an IC at three studied types for Egyptian health care facilities. Ten statements were ranked twice by the participants to reflect their perception of IC purpose as per what is currently practiced and what they believe should be practiced. RESULTS: IC implementation varies significantly (p<0.05) across the health care facilities in Egypt. The percentage of its implementation at the non-governmental facilities, governmental facilities, and university hospital was 85.9%, 77.8%, and 63.8 respectively. The first three ranked purposes of the current IC practices were: "Helping patient/guardian decide (64.9%)", "Documenting patient's/guardian's decision (59.3%)", and "Having shared decision (57.3%)". The perceived purposes of IC to be practiced were: "Informing the patient/guardian (68.4%)", "Making sure patient/guardian understand (65.3%)" and "Documenting patients/guardians decisions (65.1%)". "Being a meaningless routine" was reported by the majority to be ranked as a low purpose for IC current and preferred practices. CONCLUSION: The practice of IC is common within the Egyptian medical community. Participants believe that information disclosure "Making sure patients understand" has to help in IC decision making and its main purpose. However, unfortunately, this is not perceived as a current purpose of IC. There was consensus agreement that documenting the patient's/guardian's decision and informing the patient/guardian are perceived as both important current and preferred purposes for IC practices.


Assuntos
Tomada de Decisões , Revelação/normas , Consentimento Livre e Esclarecido/ética , Tutores Legais/psicologia , Percepção , Adulto , Estudos Transversais , Egito , Feminino , Humanos , Consentimento Livre e Esclarecido/psicologia , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
10.
Int J Biol Macromol ; 163: 649-656, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32645501

RESUMO

Zinc crosslinked supramolecular hydrogels from O-carboxymethyl chitosan biguanidine were successfully prepared. The structures of the prepared hydrogels were verified by 1H NMR, FTIR and XRD. FE-SEM verified the porous structure of hydrogels especially at high contents of Zn2+ ions. The integral procedure decomposition temperatures calculated from TGA curves showed that the thermal stability was increased upon increasing the content of Zn2+ ions. Cytotoxicity assays confirmed that the amounts of Zn2+ ions released from hydrogels were below the toxic level towards a breast cancer cell line (MCF-7). The prepared hydrogels exhibited a significant microbial inhibition towards different species of bacteria and fungi, particularly at high Zn contents. Based on the obtained interesting data, the prepared zinc/O-carboxymethyl chitosan biguanidine could be used in drug delivery and biomedical applications.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Biguanidas/química , Materiais Biocompatíveis/química , Quitosana/análogos & derivados , Hidrogéis/química , Zinco/química , Bactérias/efeitos dos fármacos , Quitosana/química , Fungos/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Difração de Raios X
11.
J Diabetes Metab Disord ; 19(2): 951-958, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33553017

RESUMO

BACKGROUND: Adherence affected by many factors in the patient or in the treatment. One of these factors is beliefs about medicine, which is modifiable. This study aimed to assess the effect of beliefs about medicines on adherence to medications in diabetic patients. METHODS: It is a cross-sectional descriptive-analytic study, conducted between March 2019 and June 2019, in Family medicine outpatient clinic, Suez Canal University, Egypt. A consecutive sample of diabetic patients presented to the clinic in the period of study was included until fulfilling sample size (82 patients). They filled validated questionnaires of the Morisky Medication Adherence Scale, Beliefs about Medicine, and socio-demographic characteristics. RESULTS: About half of the patients were non-adherent (54.9%). The necessity beliefs mean was 18.6, while the median was 20, concerns beliefs mean was 14.2, while the median was 14, overuse beliefs mean was 12.2, while the median was 13, finally mean and median of harm score was 11.0. There was a statistically significant relationship between age, education, concern, and harm score with adherence (p = 0.04, 0.02, < 0.001, and 0.03). Age was a positive predictor of adherence; and concern beliefs score was a negative predictor of adherence. CONCLUSIONS: Physicians should inquire about their patient medication beliefs and its effect on patient adherence to discover and solve concerns of diabetic patients to improve non-adherence.

12.
Int J Biol Macromol ; 165(Pt B): 2693-2701, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33098892

RESUMO

This work aims to prepare multifunctional edible coating based on alginate and Aloe vera (AV) optimized to minimum water vapor permeability (WVP) using Box-Behnken design. Titanium oxide nanoparticles (nTiO2) were incorporated into the optimized film at different contents. FTIR confirmed the structures, while XRD confirmed nTiO2 incorporation with a size ranging from 20.38 to 28.81 nm. The UV-shielding was enhanced either in the presence of AV or nTiO2. Thermal stability by TGA was improved upon increasing the nTiO2 content. WVP was significantly decreased from 21.53 g mm/m2 day kPa for calcium alginate to 7.18 g mm/m2 day kPa in the presence of AV and nTiO2 (5 wt%). Color measurements showed non-significant changes in the film's transparency after AV and nTiO2 incorporation. Mechanical and antimicrobial properties were improved in the presence of nTiO2. Shelf-life studies on tomatoes showed significant resistance to mass loss and spoilage when coated with (alginate/AV) film containing 5 wt% of nTiO2.


Assuntos
Alginatos/química , Quitosana/farmacologia , Nanopartículas/química , Preparações de Plantas/farmacologia , Alginatos/farmacologia , Aloe/química , Antibacterianos/química , Antibacterianos/farmacologia , Quitosana/química , Filmes Comestíveis , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/microbiologia , Preparações de Plantas/química , Resistência à Tração , Titânio/química
13.
Int J Biol Macromol ; 165(Pt A): 1187-1197, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33035528

RESUMO

Edible films based on chitosan biguanidine hydrochloride and CMC were optimized for the minimum water vapor permeability (WVP) using the 3-level factorial design. Titanium oxide nanoparticles (nTiO2) were incorporated in different contents into the optimized film (Owvp). FTIR and 1H NMR confirmed the successful preparation of films. FE-SEM showed that nTiO2 was homogeneously distributed, with a size of about 25.78 nm for the film containing 5 wt% of nTiO2. XRD was used to study the film's crystallinity, and calculate the crystallite size of nTiO2 using Debye-Scherrer Equation. Thermal stability, by TGA, was improved while the water vapor permeability was reduced upon increasing the nTiO2 content. Color measurements showed that the nTiO2 incorporation didn't significantly affect the transparency. Elongation at break was decreased upon nTiO2 incorporation while tensile strength and Young's modulus were increased with increasing nTiO2 up to 3 wt% then begin to decrease. The nanocomposites exhibited significant UV-barrier properties and enhanced antimicrobial activity especially at high contents of nTiO2. Shelf-life studies on green bell pepper coated with the nanocomposite films showed excellent resistance to mass loss and spoilage during storage. The obtained data confirm the efficiency of the prepared nTiO2 nanocomposite films to extend the shelf-life of food.


Assuntos
Carboximetilcelulose Sódica/química , Quitosana/química , Embalagem de Alimentos , Nanopartículas/química , Capsicum/efeitos dos fármacos , Capsicum/efeitos da radiação , Guanidina/química , Humanos , Titânio/química , Raios Ultravioleta/efeitos adversos
14.
SN Compr Clin Med ; 2(12): 2568-2575, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33195996

RESUMO

With the deteriorating situation during the COVID-19 pandemic, healthcare workers and medical students posted in wards are also supposed to be at risk of getting infected. This study aimed to evaluate knowledge, risk perception, and preventive behaviors related to the COVID-19 pandemic among undergraduate medical students in Egypt. This is a cross-sectional observational study using an anonymous online questionnaire. The survey was conducted through a link shared on social networking sites. Data were collected from 19 June 2020 to 26 June 2020. The medical students of Suez Canal University fulfilled the inclusion criteria and agreed to participate in the study were included by using convenience and snowball sampling technique (283 students). The total related knowledge score was 80.9%. The majority (83%) feel that coronavirus infection is a life-threatening illness. About 86.9% of the students perceived a COVID-19-infected person as a serious threat to society. However, three-quarters of the students (76.3%) perceived risk of infection with COVID-19 during ward rotations. About 92% of the students are practicing preventive behaviors. Female senior students have higher percentages in regard to related knowledge and practicing preventive behaviors. Students who received education about Covid-19 and students perceived higher risk of infection were more adherent to preventive measures. There is a moderate correlation between related knowledge and practicing preventive behaviors. Medical students have good knowledge, practice preventive behaviors, and perceive risk of being infected. The direction to raise knowledge and awareness will enhance practicing preventive behaviors to control the disease.

15.
Int J Biol Macromol ; 139: 614-620, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31381919

RESUMO

Chitosan biguanidine hydrochloride (CBg) was prepared as a novel multifunctional biodegradable polymer with antimicrobial and excellent water-solubility properties, and used as a crosslinker to prepare carboxymethyl cellulose (CMC)/alginate (A)/CBg edible coating. FTIR confirmed the successful preparation of CBg and CMC/A/CBg films. Wide-angle X-ray diffraction showed that the amorphous structure of CMC/A had some degree of order after CBg addition. The film thickness and solubility were decreased after CBg addition due to the formation of a dense crosslinked structure. CBg addition significantly improved the thermal properties of the films as detected from the calculated IPDT values from TGA curves. Water vapor permeability was reduced to 54% of the value of CMC/A when CBg was added by15 wt%. The addition of CBg didn't change the transparency of CMC/A films. The mechanical properties and antibacterial properties were significantly enhanced after the addition of CBg. CMC/A/CBg were coated on tomato fruits, and the shelf-life studies showed that the storage weight loss was significantly reduced, and the spoilage was inhibited after coating. These results suggest that CMC/A/CBg edible coating might be a promising candidate in food preservation industries.


Assuntos
Alginatos/química , Carboximetilcelulose Sódica/química , Filmes Comestíveis , Conservação de Alimentos , Guanidina/química , Antibacterianos/química , Anti-Infecciosos/farmacologia , Bacillus subtilis , Quitosana/química , Reagentes de Ligações Cruzadas , Escherichia coli , Embalagem de Alimentos , Solanum lycopersicum , Teste de Materiais , Permeabilidade , Polímeros/química , Solubilidade , Vapor , Streptococcus pneumoniae , Resistência à Tração , Termogravimetria , Água/química , Difração de Raios X
16.
Int J Biol Macromol ; 139: 1162-1167, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31415850

RESUMO

This study aims to prepare binary edible films made from carboxymethyl cellulose (CMC) and chitosan biguanidine hydrochloride (CBg) activated with frankincense oil (FO). The interactions between CMC, CBg and FO were confirmed by FTIR. XRD showed that the addition of FO led to decreasing the crystallinity of CMC/CBg films. The water vapour permeability was reduced upon increasing the FO content. The presence of FO made the films brighter and didn't change their transparency as detected from the color measurements. The films exhibited better mechanical properties in the presence of FO as detected from the improved values of both tensile strength and elongation at break. The prepared films exhibited excellent antibacterial activity especially at high content of FO (5%). CMC/CBg/FO films might be used potentially in the production of edible films due to their excellent physical and antibacterial properties.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Carboximetilcelulose Sódica/química , Quitosana/química , Franquincenso/química , Óleos Voláteis/química , Bacillus subtilis/efeitos dos fármacos , Teste de Materiais , Permeabilidade , Vapor , Streptococcus pneumoniae/efeitos dos fármacos , Resistência à Tração
17.
Int J Biol Macromol ; 116: 840-848, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29777814

RESUMO

This work aims to study the effect of a vinyl-modified montmorillonite (VMT) on the physical and antimicrobial properties of chitosan-graft-polyacrylic acid superabsorbent (Ch-g-PA). Ch-g-PA was first optimized using Box-Behnken design to obtain the maximum equilibrium swelling, and the model was efficient to express the experimental swelling data (R2 = 0.999). VMT was further added to the optimized Ch-g-PA in different contents 0, 4, 7 and 10 wt%. FTIR confirmed the successful synthesis of the copolymers and their nanocomposites. Morphology and the average pores size were studied using SEM. Wide angle X-ray diffraction showed the formation of exfoliated nanocomposites after VMT addition. Thermal stability studied by TGA was greatly enhanced in the presence of VMT. The swelling kinetics by Voigt-based viscoelastic model showed that the equilibrium swelling was increased by increasing the VMT up to 7 wt% then decreased after further incorporation. The superabsorbents exhibited salt and pH-responsive properties and showed a pH-reversibility at two buffer solutions (pH = 2 and pH = 9). Moreover, the prepared superabsorbents exhibited a strong bacterial and fungal killing ability which becomes more pronounced upon increasing the VMT content. The obtained results encourage the usage of the prepared copolymer nanocomposites in many fields as antimicrobial superabsorbents of improved physical properties.


Assuntos
Resinas Acrílicas , Anti-Infecciosos , Bactérias/crescimento & desenvolvimento , Bentonita , Quitosana , Resinas Acrílicas/química , Resinas Acrílicas/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Bentonita/química , Bentonita/farmacologia , Quitosana/química , Quitosana/farmacologia
18.
Int J Biol Macromol ; 116: 443-450, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29727654

RESUMO

Novel bioactive edible films based on sodium alginate (A) and chitosan biguanidine hydrochloride (CG) with different weight percents were successfully prepared. 13C NMR and 1H NMR confirmed the successful guanidylation of chitosan. Fourier transform infrared confirmed the successful reaction between CG and A. The interaction between CG and A was confirmed through the reduction of the crystalline peaks of both CG and A as detected from their wide-angle X-ray diffraction. Thermogravimetric analysis confirmed that CG enhanced the thermal stability of films as detected from the calculated integral procedure decomposition temperature (IPDT) values. CG incorporation improved the mechanical properties of dry and wet samples. A/CG films exhibited a reduced water vapor permeability and good color properties. The antibacterial study proved that the prepared films showed a remarkable antibacterial killing ability. These results revealed that A/CG films could be an alternative candidate to be used as antibacterial edible films in food industries.


Assuntos
Alginatos/química , Antibacterianos/química , Quitosana/química , Guanidina/química , Cor , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Espectroscopia de Ressonância Magnética/métodos , Permeabilidade/efeitos dos fármacos , Vapor , Temperatura , Termogravimetria/métodos , Água/química , Difração de Raios X/métodos
19.
Int J Biol Macromol ; 111: 19-27, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29292154

RESUMO

Green synthesis of novel nanocomposites series based on chitosan biguanidine grafted poly(3-hydroxybutyrate) copolymer (ChG-g-PHB) and silver nanoparticles (AgNPs) was successfully done via in situ reduction of AgNO3 in the copolymer matrix. Transmission electron microscopy verified the homogeneous dispersion of spherical shape of the AgNPs with an average particle size 12.3 to 19.2nm. X-ray diffraction pattern revealed face centered cubic structure of AgNPs. The thermal stability was improved upon increasing the AgNPs content up to 2.0%, then declined upon loading with 3.0%. Coats-Redfern model showed that the sample with 2.0% AgNPs has the highest activation energy of the thermal degradation with values of 264 and 270kJmol-1 for the 1st and 2nd degradation steps, respectively. Differential scanning calorimetry indicated that AgNPs acts as a nucleating agent for the nonisothermal melt crystallization of PHB component. Avrami equation described well the crystallization of PHB segments, with average Avrami exponent of 3.10 and 3.36 for ChG-g-PHB and its 2.0% nanocomposite, respectively. Regardless of the content of AgNPs, the antimicrobial activity of the nanocomposites is better than the neat copolymer. The sample loaded with 3.0% AgNPs showed the best antimicrobial activity with MIC value range of 0.98-1.95µgmL-1.


Assuntos
Anti-Infecciosos/química , Quitosana/química , Química Verde , Nanopartículas Metálicas/química , Anti-Infecciosos/síntese química , Biguanidas/síntese química , Biguanidas/química , Cristalização , Hidroxibutiratos/química , Poliésteres/química , Prata/química
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