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1.
Int J Biol Macromol ; 271(Pt 1): 132267, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38816292

RESUMO

In light of the need to create new materials that are safe for use in biomedical applications like wound healing and tissue engineering, a unique nanocomposite was formulated and produced in the current investigation. A biocompatible hydrogel was created using natural polymers xanthan gum (XG) and alginate (Alg). In order to enhance the mechanical characteristics of the natural polymer-based hydrogels, polyvinyl alcohol (PVA) was added to the hydrogel matrix. Subsequently, the XG-Alg hydrogel/PVA structure was combined with ZnMnFe2O4 nanoparticles in order to augment the antibacterial efficacy of the biomaterial. The XG-Alg hydrogel/PVA/ZnMnFe2O4 nanocomposite was analyzed using XRD, EDX, FT-IR, TGA, and FE-SEM techniques to determine its properties. In addition, the mechanical properties of the pure hydrogel were compared to those of the XG-Alg hydrogel/PVA/ZnMnFe2O4 nanocomposite. The nanocomposite exhibited a biocompatibility of 96.45 % and 94.32 % with HEK293T cell lines after 24 h and 48 h of incubation, respectively, in biological evaluations. Furthermore, a significant antibacterial efficacy was demonstrated against both gram-positive S. aureus and gram-negative E. coli bacteria. The findings suggest that the developed XG-Alg hydrogel/PVA/ZnMnFe2O4 nanocomposite has promising qualities for use in biomedical fields, such as tissue engineering.


Assuntos
Alginatos , Antibacterianos , Hidrogéis , Nanocompostos , Polissacarídeos Bacterianos , Álcool de Polivinil , Alginatos/química , Alginatos/farmacologia , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/farmacologia , Álcool de Polivinil/química , Nanocompostos/química , Humanos , Antibacterianos/farmacologia , Antibacterianos/química , Hidrogéis/química , Hidrogéis/farmacologia , Células HEK293 , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Nanopartículas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Testes de Sensibilidade Microbiana
2.
Anal Methods ; 16(22): 3448-3463, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38804827

RESUMO

Some physical phenomena and various chemical substances newly introduced in nanotechnology have allowed scientists to develop valuable devices in the field of food sciences. Regarding such progress, the identification of foodborne pathogenic microorganisms is an imperative subject nowadays. These bacterial species have been found to cause severe health impacts after food ingestion and can result in high mortality in acute cases. The rapid detection of foodborne bacterial species at low concentrations is in high demand in recent diagnostics. CRISPR/Cas-mediated biosensors possess the potential to overcome several challenges in classical assays such as complex pretreatments, long turnaround time, and insensitivity. Among them, colorimetric nanoprobes based on the CRISPR strategy afford promising devices for POCT (point-of-care testing) since they can be visualized with the naked eye and do not require diagnostic apparatus. In this study, we briefly classify and discuss the working principles of the different CRISPR/Cas protein agents that have been employed in biosensors so far. We assess the current status of the CRISPR system, specifically focusing on colorimetric biosensing platforms. We discuss the utilization of each Cas effector in the detection of foodborne pathogens and examine the restrictions of the existing technology. The challenges and future opportunities are also indicated and addressed.


Assuntos
Técnicas Biossensoriais , Sistemas CRISPR-Cas , Colorimetria , Microbiologia de Alimentos , Doenças Transmitidas por Alimentos , Humanos , Bactérias/isolamento & purificação , Bactérias/genética , Técnicas Biossensoriais/métodos , Colorimetria/métodos , Microbiologia de Alimentos/métodos , Doenças Transmitidas por Alimentos/diagnóstico , Doenças Transmitidas por Alimentos/microbiologia , Doenças Transmitidas por Alimentos/prevenção & controle
3.
Sci Rep ; 14(1): 6950, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38521870

RESUMO

In this study, a CoO-Fe2O3/SiO2/TiO2 (CIST) nanocomposite was synthesized and utilized as an adsorbent to remove methylene blue (MB), malachite green (MG), and copper (Cu) from aqueous environments. The synthesized nanocomposite was characterized using field emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and X-ray diffraction (XRD). Input parameters included pH (3-10), contact time (10-30 min), adsorbent amount (0.01-0.03 g), and pollutant concentration (20-60 mg L-1). The effects of these parameters on the removal process efficiency were modeled and optimized using the response surface methodology (RSM) based on the Box-Behnken design (BBD). The RSM-BBD method demonstrated the capability to develop a second-degree polynomial model with high validity (R2 ˃ 0.99) for the removal process. The optimization results using the RSM-BBD method revealed a removal efficiency of 98.01%, 93.06%, and 88.26% for MB, MG, and Cu, respectively, under optimal conditions. These conditions were a pH of 6, contact time of 10 min, adsorbent amount of 0.025 g, and concentration of 20 mg L-1. The synthesized adsorbent was recovered through five consecutive adsorption-desorption cycles using hydrochloric acid. The results showed an approximately 12% reduction from the first to the seventh cycle. Also, MB, MG, and Cu removal from real water samples in optimal conditions was achieved in the range of 81.69-98.18%. This study demonstrates the potential use of CIST nanocomposite as an accessible and reusable option for removing MB, MG, and Cu pollutants from aquatic environments.

4.
Artigo em Inglês | MEDLINE | ID: mdl-30363799

RESUMO

BACKGROUND: Platelets have a vital role in antimicrobial host defenses. The objective of this study was to evaluate if increased mean platelet volume to platelet count (MPV/PC) ratio in acute ischemic stroke patients complicated with pneumonia was associated with increased mortality risk. METHODS: The current study was conducted at Zagazig University Hospitals. It included 500 acute ischemic stroke patients classified as group 1 that included 51 patients complicated with pneumonia after admission and group 2 that included the remaining 449 patients. Clinical assessment was carried out to exclude comorbid medical illnesses likely to interfere with platelet function or morphology. Laboratory investigations including MPV/PC ratio and brain imaging were carried out for all patients. RESULTS: There was a significant difference between both groups regarding age, National Institutes of Health Stroke Scale (NIHSS) score, and mortality within 30 days (p = 0.02, 0.03, 0.01). There was a significant difference between survivors and non-survivors of group 1 regarding to pneumonia severity index (PSI) classes IV and V (p = 0.01 and 0.02, respectively). Also, there was a significant difference regarding confusion, urea ≥ 7 mmol/L, respiratory rater ≥ 30 breaths/min, systolic blood pressure ≤ 90 mmHg or diastolic blood pressure ≤ 60 mmHg, and age ≥ 65 years at pneumonia occurrence (CURB-65) scores 3, 4, and 5 (p = 0.03, 0.02, and 0.01, respectively). Moreover, there was a significant difference regarding decreased GCS score at pneumonia occurrence, higher NIHSS scores, PSI, and higher MPV/PC ratio (p = 0.01, 0.01, 0.028, and 0.01, respectively). Age > 65 years, need for mechanical ventilation, GCS score of > 9, PSI class ≥ IV, CURB-65 scores ≥ 3, and increased MPV/PC ratio were all significantly associated with 30-day mortality in group 1 (p = 0.03, 0.01, 0.001, 0.04, 0.01, and 0.03, respectively). The predictors of 30-day mortality risk factors were GCS less than 9, increased MPV/PC ratio, and CURB-65 scores ≥ 3 (p = 0.001, 0.05, and 0.01, respectively). CONCLUSIONS: Once pneumonia develops, MPV/PC ratio could be considered a significant laboratory indicator of 30-day mortality.

5.
Artigo em Inglês | MEDLINE | ID: mdl-29780234

RESUMO

BACKGROUND: Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy of the upper extremity. The aim of this study is to evaluate the body mass index (BMI) and vitamin D levels in CTS patients. METHODS: The current study was conducted at Zagazig University Hospitals. It included 50 CTS patients and 50 controls. Clinical assessment was carried out to exclude symptoms and signs of neuropathy. Laboratory investigations including vitamin D levels, glycosylated hemoglobin, liver, and kidney function were carried out for every participant. All patients underwent electrodiagnostic study and completed Boston questionnaire to assess their pain sum score, symptom severity (SSS), and functional status (FSS). RESULTS: Patients had significantly higher BMI and lower vitamin D levels compared to controls (p = 0.003 and p = 0.001, respectively). Those with severe CTS had a significantly higher BMI and lower vitamin D levels than the others (p = 0.03 and p = 0.01 respectively). No significant difference was found between CTS subgroups regarding the SSS, while a higher significant FSS and pain sum score were reported in the severe CTS patients compared to the other two groups (p = 0.01 and p = 0.04 respectively). A significant negative correlation was detected between vitamin D levels and both of BMI, and Boston pain sum scores (p = 0.01 and p = 0.03 respectively). Also, an inverse correlation was detected between vitamin D levels and both of SSS and FSS (p = 0.14, p = 0.06). Furthermore, a significant positive and negative correlation between vitamin D levels and both of conduction velocity and distal motor latency respectively was observed (p = 0.02 and p = 0.01 respectively). CONCLUSIONS: Carpal tunnel syndrome was significantly associated with hypovitaminosis D especially in patients with higher BMI. This highlights the importance of vitamin D supplements and weight loss regimes to minimize the severity of their pain.

6.
Artigo em Inglês | MEDLINE | ID: mdl-29881250

RESUMO

BACKGROUND: Multiple sclerosis (MS) and systemic lupus erythematosus (SLE) are chronic autoimmune mediated diseases with strong genetic and environmental components. The aim of this study is to evaluate the association of STAT4 gene polymorphism with multiple sclerosis (MS) and juvenile onset systemic lupus erythematosus (JO-SLE) and its relation to disease severity. METHODS: Group 1 consisted of 40 MS patients while group 2 included 40 JO-SLE patients. Forty healthy volunteers (controls) were included in this study. STAT4 genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS: The STAT4 CC genotype and GC genotype frequencies were significantly more detected in MS and JO-SLE patients than in controls. The frequency of the STAT4 C allele was significantly higher in patients with MS and those with JSLE compared to controls. Malar rash, photosensitivity, and hair falling were significantly more detected in CC subtype. Malar rash, photosensitivity, and hair falling were significantly more detected in CC subtype. Increased 24-h protein in urine (mg/24 h) and ANA positivity, anti-ds-DNA, anti Sm antibodies' detection and decreased C3 and C4 levels showed a significantly difference in CC patients. Meanwhile, only increased 24-h protein in urine (mg/24 h) and ANA positivity were significantly more detected in GC patients. STAT4 CC genotype showed a significant increase in the SLE activity index (SLEAI) score and damage index as compared to the STAT4 GG genotype patients. No significant difference was detected in MS Kurtzke's Expanded Disability Status Scale (EDSS) comparing different STATE 4 genotypes. CONCLUSIONS: STAT4 polymorphism was significantly associated with MS and JO-SLE. Though homozygous JO-SLE patients are more risky for severe disease manifestations, homozygous MS patients are not risky for severe disease disability.

7.
Egypt J Immunol ; 16(2): 27-36, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-22059351

RESUMO

Chronic lymphocytic leukemia (CLL) is a haematopoetic neoplasm caused primarily by defects in apoptosis mechanisms and complicated by progressive marrow failure, immunosupression and increased resistance to chemotherapy. The CD40-CD40 ligand (CD40L) interaction has been shown to significantly increase antigen presentation in normal and malignant B-cells and it is a powerful regulator of cell survival. Bcl-2 expression is common in CLL and is associated with decreased overall survival. Our objective was to asses CD40 ligand (CD154) and Bcl-2 expressions and their correlation with clinical and laboratory features in CLL patients. This study was conducted on 40 subjects, including 10 healthy volunteers as the control group and 30 patients presented with de novo chronic lymphocytic leukemia (CLL), all of them were subjected to thorough history taking, full clinical examinations, routine laboratory investigations and flowcytometric assessment of CD40L and Bcl-2 on lymphocytes. There was a highly significant increase in TLC, absolute lymphocytic count, serum LDH, B2-microglobulin and Bcl-2 expression (P<0.001); there was a significant increase in CD40L expression (P<0.05); whereas there was a highly significant decrease in hemoglobin concentration and platelets count between the study group (P<0.001). There was no significant difference as regard direct Coombs' test between both groups. There was no significant relation between CD154 expression and clinical findings, Rai staging system and other laboratory parameters. CD40L expression is increased with staging of Modified Rai staging system but not reaching the significant level. There was no significant correlation between CD154 expression and some of clinical and laboratory parameters, whereas there was only significantly negative correlation between Bcl-2 expression and both haemoglobin concentration and platelets count (P<0.001). Combination of Bcl-2 antisense oligonucleotide with conventional chemotherapeutic drugs may enhance the cytotoxicity of these drugs and induces apoptosis.


Assuntos
Linfócitos B/metabolismo , Ligante de CD40/metabolismo , Leucemia Linfocítica Crônica de Células B/imunologia , Leucemia Linfocítica Crônica de Células B/fisiopatologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Idoso , Apoptose/imunologia , Linfócitos B/imunologia , Linfócitos B/patologia , Ligante de CD40/genética , Ligante de CD40/imunologia , Separação Celular , Progressão da Doença , Feminino , Citometria de Fluxo , Hemoglobinas/metabolismo , Humanos , Imunofenotipagem , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Contagem de Plaquetas , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/imunologia
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