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1.
Foods ; 12(24)2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38137258

RESUMO

In this study, sodium carboxymethyl cellulose (CMCNa) bioactive films, crosslinked with citric acid (CA), were prepared and comprehensively examined for their suitability in various applications, focusing on food packaging. The films displayed favourable properties, including appropriate thickness, transparency, and moisture content, essential for packaging purposes. Moreover, the films exhibited excellent moisture absorption rate and barrier properties, attributed to the high concentration of CMCNa and the inclusion of a CA. These films presented no significant effect of crosslinking and bioactive components on their mechanical strength, as evidenced by tensile strength and elongation at break values. Thermal stability was demonstrated in the distinct weight loss events at different temperature ranges, with crosslinking contributing to slightly enhanced thermal performance. Furthermore, the films showed varying antioxidant activity levels, influenced by temperature and the solubility of the films in different media, indicating their potential for diverse applications. Overall, these bioactive films showed promise as versatile materials with desirable properties for food packaging and related applications, where the controlled release of bioactive components is advantageous for enhancing the shelf life and safety of food products. These findings contribute to the growing research in biodegradable and functional food packaging materials.

2.
Foods ; 12(11)2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37297404

RESUMO

Corn silk (CS) extracts are reported to contain flavonoids (appx. 59.65 mg quercetin/g), polysaccharides (appx. 58.75 w.%), steroids (appx. 38.3 × 10-3 to 368.9 × 10-3 mg/mL), polyphenols (appx. 77.89 mg/GAE/g) and other functional biological substances. This study investigated the antioxidant activity of corn silk extracts related to their functional compounds. The radical scavenging effect of corn silk extracts was evaluated by the spin-trapping electron paramagnetic resonance (EPR) technique, 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzo-thiazoline-6-sulfonate) (ABTS•+) free radical measurement, ferric ion-reducing antioxidant power, and copper ion reductive capacity. It was found that the maturity stage of CS plant materials and the applied extraction procedure of their bioactive compounds have a profound effect on the radical scavenging capacity. Differences in the antioxidant activity of the studied corn silk samples based on their maturity were also confirmed. The strongest DPPH radical scavenging effect was observed for the corn silk mature stage (CS-M)stage (CS-MS) (65.20 ± 0.90)%, followed by the silky stage (CS-S) (59.33 ± 0.61)% and the milky stage (CS-M) (59.20 ± 0.92)%, respectively. In general, the final maturity stage (CS-MS) provided the most potent antioxidant effect, followed by the earliest maturity stage (CS-S) and the second maturity stage (CS-M).

3.
Foods ; 12(7)2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-37048218

RESUMO

Curcuma is a world-renowned herb known for its immense health benefits. In this study, physicochemical analyses were performed on the curcumin standard sample and curcumin multiple emulsions. The emulsions were analysed for thermal and structural stability for 21 days. Confocal laser microscopy (CLSM) was performed in order to observe the emulsion encapsulation. Modulated differential scanning calorimetry (MDSC) and HPLC methods revealed a variety of curcuminoids (curcumin, demethoxycurcumin, bisdemethoxycurcumin, and cyclocurcumin) in the investigated curcumin standard. In addition, the MDSC method was found to be suitable and comparable to HPLC for determining the curcuminoid substances. The analysis of the curcumin release revealed a value of 0.18 w.% after 14 days as the equilibrium value. Furthermore, an increase in the sizes of the emulsions was observed at the end of the 21-day study. The emulsion stability index (ESI) was used to measure the stability of multiple emulsions. The ESI reached 55.8% between 7 and 21 days later. Nano droplets of the oil phase loaded with dispersed curcumin particles captured inside the water-based carboxymethylcellulose micelles were clearly observed by CLSM.

4.
Foods ; 12(4)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36832908

RESUMO

One of the biggest challenges faced by the meat industry is maintaining the freshness of meat while extending its shelf life. Advanced packaging systems and food preservation techniques are highly beneficial in this regard. However, the energy crisis and environmental pollution demand an economically feasible and environmentally sustainable preservation method. Emulsion coatings (ECs) are highly trending in the food packaging industry. Efficiently developed coatings can preserve food, increase nutritional composition, and control antioxidants' release simultaneously. However, their construction has many challenges, especially for meat. Therefore, the following review focuses on the essential aspects of developing ECs for meat. The study begins by classifying emulsions based on composition and particle size, followed by a discussion on the physical properties, such as ingredient separation, rheology, and thermal characteristics. Furthermore, it discusses the lipid and protein oxidation and antimicrobial characteristics of ECs, which are necessary for other aspects to be relevant. Lastly, the review presents the limitations of the literature while discussing the future trends. ECs fabricated with antimicrobial/antioxidant properties present promising results in increasing the shelf life of meat while preserving its sensory aspects. In general, ECs are highly sustainable and effective packaging systems for meat industries.

5.
Adv Colloid Interface Sci ; 304: 102681, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35483124

RESUMO

Polymeric materials play a vital role in our daily life, but the growing concern for the environment demands economical and natural biopolymers that can be cross-linked to create technologically innovative lightweight materials. Their cellular matrix with extreme flexibility makes them highly acceptable for application prospects in material science, engineering, and biomedical applications. Furthermore, their biocompatibility, mechanical properties, and structural diversity provide a gateway to research them to form technologically important materials. In the light of the same, the review covers cellulose derivatives. The first section of the study covers the general properties and applications of cellulose and its derivatives. Then, the biopolymers are characterised based on their dielectric properties, crystallinity, rheology, and mechanical properties. An in-depth analysis of the diffuse process of swelling and dissolution followed by a brief discussion on diffusion and diffusion of crosslinking has been done. The review also covers a section on swelling and swelling kinetics of carboxymethyl cellulose (CMC) and hydroxyethyl cellulose (HEC). The examination of all the aforementioned parameters gives an insight into the future aspects of the biopolymers. Lastly, the study briefly covers some preferred choices of cross-linking agents and their effect on the biopolymers.


Assuntos
Carboximetilcelulose Sódica , Celulose , Biopolímeros/química , Carboximetilcelulose Sódica/química , Celulose/química , Hidrogéis/química , Reologia
6.
Ann N Y Acad Sci ; 1482(1): 36-48, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33103249

RESUMO

The causal link between high-risk human papillomavirus (hr-HPV) infection and cervical, anogenital, and some oropharyngeal malignancies has been established by both molecular and epidemiological data. The association between HPV and esophageal squamous cell carcinoma (ESCC) remains controversial, as is the true prevalence of HPV infection in ESCC. The wide range in reported rates reflects variability in the primary literature, with some larger scale case-control studies suggesting the infection rates range from 0% to 78%. Interactions between HPV and the Barrett's metaplasia-dysplasia-carcinoma sequence have been explored, and these studies have shown some conflicting data. Overall, systematic reviews have reported the prevalence of HPV-positive DNA in esophageal adenocarcinoma patients of between 13% and 35%. Postulated reasons for discrepancies in HPV prevalence rates in esophageal cancer include variations in testing methodology and assay sensitivities; technical issues, including the lack of a gold-standard primer; types of specimens utilized (fresh-frozen versus formalin-fixed tissue); geographical variation; cross-contamination; and small sample sizes. Thus, efforts must be undertaken to (1) standardize HPV testing, ideally in a central laboratory and utilizing tests that detect viral transcriptional activity; (2) avoid cross-contamination; and (3) recruit large numbers of patients to accurately ascertain HPV rates in esophageal malignancy.


Assuntos
Adenocarcinoma/patologia , Esôfago de Barrett/virologia , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Infecções por Papillomavirus/patologia , Adenocarcinoma/virologia , Adolescente , Adulto , Idoso , Alphapapillomavirus/isolamento & purificação , Esôfago de Barrett/patologia , Neoplasias Esofágicas/virologia , Carcinoma de Células Escamosas do Esôfago/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Papillomavirus/epidemiologia , Adulto Jovem
7.
World J Gastroenterol ; 26(21): 2729-2739, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32550750

RESUMO

High-risk human papillomavirus has been suggested as a risk factor for esophageal adenocarcinoma. Tumor human papillomavirus status has been reported to confer a favorable prognosis in esophageal adenocarcinoma. The size of the primary tumor and degree of lymphatic spread determines the prognosis of esophageal carcinomas. Lymph node status has been found to be a predictor of recurrent disease as well as 5-year survival in esophageal malignancies. In human papillomavirus driven cancers, e.g. cervical, anogenital, head and neck cancers, associated lymph nodes with a high viral load suggest metastatic lymph node involvement. Thus, human papillomavirus could potentially be useful as a marker of micro-metastases. To date, there have been no reported studies regarding human papillomavirus involvement in lymph nodes of metastatic esophageal adenocarcinoma. This review highlights the importance of investigating human papillomavirus in lymph node metastasis of esophageal adenocarcinoma based on data derived from other human papillomavirus driven cancers.


Assuntos
Adenocarcinoma/mortalidade , Alphapapillomavirus/isolamento & purificação , Neoplasias Esofágicas/mortalidade , Linfonodos/virologia , Metástase Linfática/patologia , Infecções por Papillomavirus/diagnóstico , Adenocarcinoma/patologia , Adenocarcinoma/virologia , Neoplasias do Ânus/mortalidade , Neoplasias do Ânus/patologia , Neoplasias do Ânus/virologia , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/virologia , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/virologia , Humanos , Linfonodos/patologia , Masculino , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Neoplasias Penianas/mortalidade , Neoplasias Penianas/patologia , Neoplasias Penianas/virologia , Prognóstico , Fatores de Risco , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Neoplasias Gástricas/virologia , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Carga Viral , Neoplasias Vulvares/mortalidade , Neoplasias Vulvares/patologia , Neoplasias Vulvares/virologia
8.
JAMA Netw Open ; 3(2): e1921189, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-32058552

RESUMO

Importance: The presence of high-risk human papillomavirus (HPV) has been associated with a favorable outcome in Barrett high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC). Nevertheless, the prognostic significance of other HPV-related biomarkers (ie, retinoblastoma protein [pRb], cyclin D1 [CD1], minichromosome maintenance protein [MCM2] and Ki-67) is unknown. Objective: To examine the association between HPV-related biomarkers and survival in adult patients with Barrett HGD and EAC. Design, Setting, and Participants: This retrospective case-control study examined the hypothesis that the HPV-related cell cycle markers (pRb, CD1, and Ki-67) and the viral surrogate marker (MCM2) may be associated with a favorable prognosis in Barrett HGD and EAC. Pretreatment biopsies were used for HPV DNA determination via polymerase chain reaction and immunohistochemistry for the HPV-related biomarkers. Recruitment of patients occurred in secondary and tertiary referral centers, with 151 patients assessed for eligibility. The study period was from December 1, 2002, to November 28, 2017, and the dates of analysis were from September 9, 2011, to November 28, 2017. Main Outcomes and Measures: Disease-free survival and overall survival. Results: Of 151 patients assessed for eligibility, 9 were excluded. Among the 142 patients with Barrett HGD or EAC (126 [88.7%] men; mean [SD] age, 66.0 [12.1] years; 142 [100%] white), 37 were HPV positive and 105 were HPV negative. No association with disease-free survival was noted for pRb, CD1, Ki-67, and MCM2. In regard to overall survival, only low expression of CD1 had a favorable prognosis (hazard ratio [HR], 0.53; 95% CI, 0.30-0.95; adjusted P = .03). All the biomarkers stratified by HPV status showed significant associations with survival. Patients with HPV-positive, low-expression pRb esophageal tumors were associated with a significantly improved disease-free survival compared with the HPV-negative, high-expression Rb tumors (HR, 0.33; 95% CI, 0.12-0.93; adjusted P = .04). Similarly, HPV-positive, low-expression CD1 was associated with a significantly favorable disease-free survival (HR, 0.26; 95% CI, 0.09-0.76; adjusted P = .01), as was HPV-positive, high-expression MCM2 (HR, 0.27; 95% CI, 0.09-0.78; adjusted P = .02). In regard to overall survival, HPV was significantly associated only with low CD1 (HR, 0.38; 95% CI, 0.15-0.94; adjusted P = .04). Conclusions and Relevance: This study's findings suggest that low expression of CD1 appears to be an independent prognostic marker in Barrett HGD and EAC. Human papillomavirus positivity in combination with pRb, CD1, MCM2, and Ki-67 was associated with a survival benefit in esophageal tumors. These findings suggest the possibility of personalization of therapy for Barrett HGD and EAC based on viral status.


Assuntos
Adenocarcinoma , Esôfago de Barrett , Neoplasias Esofágicas , Infecções por Papillomavirus , Adenocarcinoma/complicações , Adenocarcinoma/diagnóstico , Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Idoso , Esôfago de Barrett/complicações , Esôfago de Barrett/diagnóstico , Esôfago de Barrett/genética , Esôfago de Barrett/mortalidade , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Intervalo Livre de Doença , Neoplasias Esofágicas/complicações , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/mortalidade , Feminino , Humanos , Antígeno Ki-67/genética , Masculino , Pessoa de Meia-Idade , Componente 2 do Complexo de Manutenção de Minicromossomo/genética , Papillomaviridae/genética , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Prognóstico , Estudos Retrospectivos
9.
Genes (Basel) ; 11(1)2019 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-31861886

RESUMO

Ionising radiation (IR) is known to induce a wide variety of lesions in DNA. In this review, we compared three different techniques that examined the DNA sequence preference of IR-induced DNA damage at nucleotide resolution. These three techniques were: the linear amplification/polymerase stop assay, the end-labelling procedure, and Illumina next-generation genome-wide sequencing. The DNA sequence preference of IR-induced DNA damage was compared in purified DNA sequences including human genomic DNA. It was found that the DNA sequence preference of IR-induced DNA damage identified by the end-labelling procedure (that mainly detected single-strand breaks) and Illumina next-generation genome-wide sequencing (that mainly detected double-strand breaks) was at C nucleotides, while the linear amplification/polymerase stop assay (that mainly detected base damage) was at G nucleotides. A consensus sequence at the IR-induced DNA damage was found to be 5'-AGGC*C for the end-labelling technique, 5'-GGC*MH (where * is the cleavage site, M is A or C, H is any nucleotide except G) for the genome-wide technique, and 5'-GG* for the linear amplification/polymerase stop procedure. These three different approaches are important because they provide a deeper insight into the mechanism of action of IR-induced DNA damage.


Assuntos
Dano ao DNA , Genoma Humano/efeitos da radiação , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Mitocôndrias/genética , Mitocôndrias/efeitos da radiação , Radiação Ionizante , Análise de Sequência de DNA
10.
Mol Biol Rep ; 46(4): 3731-3745, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31037547

RESUMO

For ionising radiation (IR)-induced cellular toxicity, DNA cleavage is thought to be a crucial step. In this paper, the genome-wide DNA sequence preference of gamma radiation-induced cleavage was investigated in purified human DNA. We utilised Illumina short read technology and over 80 million double-strand breaks (DSBs) were analysed in this study. The frequency of occurrence of individual nucleotides at the 50,000 most frequently cleaved sites was calculated and C nucleotides were found to be most prevalent at the cleavage site, followed by G and T, with A being the least prevalent. 5'-C*C and 5'-CC* dinucleotides (where * is the cleavage site) were found to be the present at the highest frequency at the cleavage site; while it was 5'-CC*C for trinucleotides and 5'-GCC*C and 5'-CC*CC for tetranucleotides. The frequency of occurrence of individual nucleotides at the most frequently cleaved sites was determined and the nucleotides in the sequence 5'-GGC*MH (where M is A or C, H is any nucleotide except G) were found to occur most frequently for DNA that was treated with endonuclease IV (to remove blocking 3'-phosphoglycolate termini); and 5'-GSC*MH (where S is G or C) for non-endonuclease IV-treated DNA. It was concluded that GC-rich sequences were preferentially targeted for cleavage by gamma irradiation. This was the first occasion that an extensive examination of the genome-wide DNA sequence preference of IR-induced DSBs has been performed.


Assuntos
Sequência de Bases/genética , Ilhas de CpG/genética , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Clivagem do DNA/efeitos da radiação , Dano ao DNA/efeitos da radiação , DNA/efeitos da radiação , Sequência de Bases/efeitos da radiação , Ilhas de CpG/efeitos da radiação , DNA/genética , Raios gama , Estudo de Associação Genômica Ampla , Células HeLa , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Radiação Ionizante
11.
Radiat Res ; 189(3): 238-250, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29286256

RESUMO

In this work, we examined the DNA sequence preference of gamma-radiation-induced DNA damage in purified DNA sequences after heat treatment. DNA was fluorescently end-labeled and gamma-radiation-induced DNA cleavage was examined using capillary electrophoresis with laser-induced fluorescence detection. Our findings provide evidence that gamma-radiation-induced DNA damage to end-labeled DNA is nonrandom and has a sequence preference. The degree of cleavage was quantified at each nucleotide, and we observed that preferential cleavage occurred at C nucleotides with lesser cleavage at G nucleotides, while being very low at T nucleotides. The differences in percentage cleavage at individual nucleotides ranged up to sixfold. The DNA sequences surrounding the most intense radiation-induced DNA cleavage sites were examined and a consensus sequence 5'-AGGC*C (where C* is the cleavage site) was found. The highest intensity gamma-radiation-induced DNA cleavage sites were found at the dinucleotides, 5'-GG*, 5'-GC*, 5'-C*C and 5'-G*G and at the trinucleotides, 5'-GG*C, 5'-TC*A, 5'-GG*G and 5'-GC*C. These findings have implications for our understanding of ionizing radiation-induced DNA damage.


Assuntos
Dano ao DNA , DNA/genética , Raios gama/efeitos adversos , Temperatura Alta , Sequência de Bases , DNA/metabolismo , Clivagem do DNA/efeitos da radiação , Reação em Cadeia da Polimerase
12.
J Biol Inorg Chem ; 22(6): 881-892, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28509989

RESUMO

Bleomycin is an anti-tumour agent that is clinically used to treat several types of cancers. Bleomycin cleaves DNA at specific DNA sequences and recent genome-wide DNA sequencing specificity data indicated that the sequence 5'-RTGT*AY (where T* is the site of bleomycin cleavage, R is G/A and Y is T/C) is preferentially cleaved by bleomycin in human cells. Based on this DNA sequence, we constructed a plasmid clone to explore this bleomycin cleavage preference. By systematic variation of single nucleotides in the 5'-RTGT*AY sequence, we were able to investigate the effect of nucleotide changes on bleomycin cleavage efficiency. We observed that the preferred consensus DNA sequence for bleomycin cleavage in the plasmid clone was 5'-YYGT*AW (where W is A/T). The most highly cleaved sequence was 5'-TCGT*AT and, in fact, the seven most highly cleaved sequences conformed to the consensus sequence 5'-YYGT*AW. A comparison with genome-wide results was also performed and while the core sequence was similar in both environments, the surrounding nucleotides were different.


Assuntos
Bleomicina/farmacologia , Clivagem do DNA/efeitos dos fármacos , DNA/genética , Sequência de Bases
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