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1.
Plants (Basel) ; 12(23)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38068564

RESUMO

Polyploidy is a significant evolutionary process in plants that involves the duplication of genomic content and has been recognized as a key mechanism driving plant diversification and adaptation. In natural populations, polyploids frequently arise from unreduced gametes, which subsequently fuse with reduced or unreduced gametes, resulting in triploid or tetraploid offspring, respectively. Cannabis sativa L. is a diploid species, but recent work using artificially induced polyploidy has demonstrated its potential advantages in an agricultural setting. Further, recent work has identified that some elite clonal cultivars, vis. Mac1, are triploid, with no indication that they were artificially produced. The current study was conducted to determine if polyploidy is a naturally occurring phenomenon in cannabis and to estimate the frequency of this phenomenon across populations. To do this, the presence of natural triploid individuals was evaluated in 13 seedling populations of cannabis using a flow cytometry analysis. Among the examined populations, natural triploids were identified in 10 groups with an average frequency of approximately 0.5%. The highest frequency of natural triploids was observed in a self-pollinated population at 2.3%. This research demonstrates that polyploidy is a naturally occurring event in cannabis and triploids are present at an average of approximately 0.5%, or 1 in 200 plants. These data shed light on the natural variation in ploidy within cannabis populations and contribute valuable insights to the understanding of cannabis genetics and breeding practices.

2.
HPB (Oxford) ; 25(8): 907-914, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37149487

RESUMO

BACKGROUND: The present study evaluates the impact of the pandemic on outcomes after surgical treatment for primary liver cancer in a high-volume hepatopancreatobiliary surgery center. METHODS: Patients, who underwent liver resection for primary liver resection between January 2019 and February 2020, comprised pre-pandemic control group. The pandemic period was divided into two timeframes: early pandemic (March 2020-January 2021) and late pandemic (February 2021-December 2021). Liver resections during 2022 were considered as the post-pandemic period. Peri-, and postoperative patient data were gathered from a prospectively maintained database. RESULTS: Two-hundred-eighty-one patients underwent liver resection for primary liver cancer. The number of procedures decreased by 37.1% during early phase of pandemic, but then increased by 66.7% during late phase, which was comparable to post-pandemic phase. Postoperative outcomes were similar between four phases. The duration of hospital stay was longer during the late phase, but not significantly different compared to other groups. CONCLUSION: Despite an initial reduction in number of surgeries, COVID-19 pandemic had no negative effect on outcomes of surgical treatment for primary liver cancer. The structured standard operating protocol in a high-volume and highly specialized surgical center can withstand negative effects, a pandemic may have on treatment of patients.


Assuntos
COVID-19 , Neoplasias Hepáticas , Humanos , COVID-19/epidemiologia , Pandemias , Bases de Dados Factuais , Padrões de Referência , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/cirurgia
3.
Macromol Biosci ; 23(2): e2200386, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36398565

RESUMO

Attempts are being made to develop an ideal wound dressing with excellent biomechanical and biological properties. Here, a thermos-responsive hydrogel is fabricated using chitosan (CTS) with various concentrations (1%, 2.5%, and 5% w/v) of solubilized placental extracellular matrix (ECM) and 20% ß-glycerophosphate to optimize a smart wound dressing hydrogel with improved biological behavior. The thermo-responsive CTS (TCTS) alone or loaded with ECMs (ECM-TCTS) demonstrate uniform morphology using SEM. TCTS and ECM1%-TCTS and ECM2.5%-TCTS show a gelation time of 5 min at 37 °C, while no gel formation is observed at 4 and 25 °C. ECM5%-TCTS forms gel at both 25 and 37 °C. The degradation and swelling ratios increase as the ECM content of the hydrogel increase. All the constructs show excellent biocompatibility in vitro and in vivo, however, the hydrogels with a higher concentration of ECM demonstrate better cell adhesion for fibroblast cells and induce expression of angiogenic factors (VEGF and VEGFR) from HUVEC. Only the ECM5%-TCTS has antibacterial activity against Acinetobacter baumannii ATCC 19606. The data obtained from the current study suggest the ECM2.5%-TCTS as an optimized smart biomimetic wound dressing with improved angiogenic properties now promises to proceed with pre-clinical and clinical investigations.


Assuntos
Quitosana , Hidrogéis , Gravidez , Feminino , Humanos , Hidrogéis/farmacologia , Quitosana/farmacologia , Biomimética , Cicatrização , Placenta , Bandagens , Antibacterianos/farmacologia , Proteínas da Matriz Extracelular
4.
Comb Chem High Throughput Screen ; 23(9): 981-987, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32407264

RESUMO

BACKGROUND AND OBJECTIVE: The SOX2OT lcnRNA has been recognized as a positive regulator in the transcription regulation of the SOX2 gene. Recent studies have approved the dysregulation of SOX2OT lncRNA expression patterns in some common cancer types, including esophageal, lung, and breast cancer. The objective of the present study was to investigate the correlation between overexpression of SOX2OT lcnRNA and susceptibility to breast cancer. METHODS: SOX2OT lncRNA expression profiling in 15 breast cancer and normal tumour-adjacent breast tissue samples was performed by using qRT-PCR. To evaluate the diagnostic potential of the SOX2OT lncRNA, we performed ROC curve analyses. RESULTS: The expression of SOX2OT lncRNA in patients suffering from breast cancer revealed a significant overexpression in comparison with the healthy group (P<0.001). Significantly, the elevated circulating SOX2OT lncRNA was found specific to breast cancer and could differentiate breast cancer from controls with 100% of both sensitivity and specificity. Based on the Kaplan- Meier analysis, there was no significant correlation between SOX2OT lcnRNA expression and overall survival. CONCLUSION: The results confirmed the association between breast cancer and higher SOX2OT lncRNA expression. According to the ROC curve results, SOX2OT lcnRNA could be a new measurable indicator of the breast cancer and a potential therapeutic target for breast cancer patients.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , RNA Longo não Codificante/genética , Adulto , Idoso , Biomarcadores Tumorais/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase
5.
Talanta ; 178: 870-878, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29136908

RESUMO

A new, fast and inexpensive colorimetric sensor was developed for chiral recognition of tryptophan enantiomers using chitosan-capped silver nanoparticles. The function of the sensor was based on scanometry and spectrophotometry of the colored product of a reaction solution containing a mixture of chitosan-capped silver nanoparticles, phosphate buffer and tryptophan enantiomers. The image of the colored solution was taken using the scanometer and the corresponding color values were obtained using Photoshop software which subsequently were used for optimization of the experimental parameters as the analytical signal. Two types of color values system were investigated: RGB (red, green and blue values) and CMYK (cyan, magenta, yellow and black values). The color values indicated that L-tryptophan had better interaction than D-tryptophan with chitosan-capped silver nanoparticles. A linear relationship between the analytical signal and the concentration of L-tryptophan was obtained in the concentration range of 1.3 × 10-5-4.6 × 10-4molL-1. Detection limits, were obtained to be 2.1 × 10-6, 2.4 × 10-6 and 3.8 × 10-6molL-1 for L-tryptophan based on R (red), G (green) and B (blue) values, respectively.


Assuntos
Quitosana/química , Nanopartículas Metálicas/química , Prata/química , Espectrofotometria , Temperatura , Triptofano/química , Soluções Tampão , Cor , Colorimetria , Concentração de Íons de Hidrogênio , Estereoisomerismo
6.
Biotechnol Appl Biochem ; 65(2): 274-280, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28326608

RESUMO

DNAzyme and aptamer conjugations have already been used for sensitive and accurate detection of several molecules. In this study, we tested the relationship between conjugation orientation of DNAzyme and aflatoxin B1 aptamer and their subsequent peroxidase activity. Circular dichroism (CD) spectroscopy and biochemical analysis were used here to differentiate between these two conjugation patterns. Results showed that DNAzyme-aptamer has more catalytic activity and efficiency than aptamer-DNAzyme. Thereby, DNAzyme-aptamer with its superior efficiency can be used for design and development of more sensitive aflatoxin B1 DNA based biosensors.


Assuntos
Aflatoxina B1/análise , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , DNA Catalítico/química , Benzidinas/análise , Compostos Cromogênicos/análise , Peróxido de Hidrogênio/análise , Oxirredução , Peroxidase/química
7.
J Toxicol ; 2017: 2461354, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28588614

RESUMO

Combination of aptamers with DNAzymes attracted intense attention for development of DNA-based biosensors for detection of mycotoxins. In the present study a combination of aflatoxin B1 specific aptamer and HRP- (horseradish peroxidase-) mimicking DNAzyme was optimized for detecting aflatoxin B1. Detecting approach is based on the binding affinity of aflatoxin B1 to its specific aptamer and conversion of substrate to a detectable colorimetric signal by a linked DNAzyme. Compared to conventional methods for aflatoxin B1 detection, DNA-based assay has the advantages of low cost, long-term stability, and rapid, simple, and user-friendly steps.

8.
Artigo em Inglês | MEDLINE | ID: mdl-28549294

RESUMO

A simple, fast and green method for chiral recognition of S- and R-naproxen has been introduced. The method was based on quenching of the fluorescence intensity of bovine serum albumin-stabilized gold nanoclusters in the presence of naproxen enantiomers. The quenching intensity in the presence of S-naproxen was higher than R-naproxen when phosphate buffer solution at pH7.0 was used. The chiral recognition occurred due to steric effect between bovine serum albumin conformation and naproxen enantiomers. Two linear determination range were established as 7.4×10-7-9.1×10-6 and 9.1×10-6-3.1×10-5molL-1 for both enantiomers and detection limits of 7.4×10-8molL-1 and 9.5×10-8molL-1 were obtained for S- and R-naproxen, respectively. The developed method showed good repeatability and reproducibility for the analysis of a synthetic sample. To make the procedure applicable to biological samples, the removal of heavy metals from the sample is suggested before any analytical attempt.


Assuntos
Nanopartículas Metálicas/química , Naproxeno/análise , Naproxeno/química , Espectrometria de Fluorescência/métodos , Ouro/química , Concentração de Íons de Hidrogênio , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes , Soroalbumina Bovina/química , Estereoisomerismo
9.
Avicenna J Med Biotechnol ; 9(2): 109-112, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28496951

RESUMO

BACKGROUND: Among diverse protein purification systems, affinity chromatography is the most attractive one in the purification process of coagulation factors. Coagulation factor VII is a plasma serine protease that has a significant role in natural human hemostasis and its recombinant form such as AryoSeven™, has been applied in clinical treatment of bleeding disorders. Immunoaffinity chromatography is the purification method of choice that is currently applied in the development of coagulation factor VIIa products. Aptamers as nucleic acid based affinity ligands are more promising than monoclonal antibodies. In addition, DNA aptamers are more acceptable than RNA ones in this regard. METHODS: In this study, two of the aptameric DNA oligonucleotides that showed acceptable affinities for purification of coagulation factor VIIa from plasma, were selected to evaluate their affinity against Aryoseven. A serial dilution of fluorescence labeled aptamers was incubated against the concentration of 1 nM from Aryoseven. Then, a fluorescence index was calculated according to the fluorescence intensity data measured from test and control samples. The dissociation constant of aptamers was calculated according to the fluorescence index using Prism5 software. RESULTS: Results showed that the binding affinity of the 44 nucleotide aptamer was more than 81 nucleotide aptamer sequence. As a result, this aptamer could be optimized in order to develop aptamer based affinity chromatography process for this form of recombinant coagulation factor VIIa. DISCUSSION: Aptamers with shorter length of sequence could show higher affinity in target binding, as they could adapt more easily to suitable conformation according to target interaction. However, it should be considered that the selectivity of affinity ligands is also important for target purification and analytical applications.

10.
Iran Endod J ; 12(1): 74-77, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28179929

RESUMO

INTRODUCTION: A desirable quality of any endodontic sealer is its ability to be tooth color friendly. Therefore the aim of the present study was to evaluate the tooth discoloration potential of a nano zinc oxide-eugenol (NZOE) sealer. METHODS AND MATERIALS: In order to evaluate tooth discoloration, the pulp chamber of 60 human maxillary central and lateral incisors were filled with one of the sealers, naming AH-26 (resin-based sealer), Pulpdent sealer (ZOE-based) and a NZOE experimental sealer. Color measurements was assessed at the baseline (before placement of sealers) (T0), 24 h (T1) and 72 h (T2) h, 1-week (T3), and 1-month (T4) after the placement of sealers using the Easy Shade spectrophotometer. Data were analyzed in SPSS software using one-way ANOVA, and repeated measured ANOVA. RESULTS: No significant differences were observed when the paired comparison test was performed (P>0.05). CONCLUSION: The tested NZOE sealer had similar tooth discoloration potential in comparison with AH-26 and ZOE sealer.

11.
Protein J ; 35(2): 81-99, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26984473

RESUMO

Aptamers are single stranded oligonucleotides, comparable to monoclonal antibodies (mAbs) in selectivity and affinity and have significant strategic properties in design, development and applications more than mAbs. Ease of design and development, simple chemical modification and the attachment of functional groups, easily handling and more adaptability with analytical methods, small size and adaptation with nanostructures are the valuable characteristics of aptamers in comparison to large protein based ligands. Among a broad range of targets that their specific aptamers developed, proteins and peptides have significant position according to the number of related studies performed so far. Since proteins control many of important physiological and pathological incidents in the living organisms, particularly human beings and because of the benefits of aptamers in clinical and analytical applications, aptamer related technologies in the field of proteins and peptides are under progress, exclusively. Currently, there is only one FDA approved therapeutic aptamer in the pharmaceutical market, which is specific to vascular endothelial growth factor and is prescribed for age related macular degenerative disease. Additionally, there are several aptamers in the different phases of clinical trials. Almost all of these aptamers are specific to clinically important peptide or protein targets. In addition, the application of protein specific aptamers in the design and development of targeted drug delivery systems and diagnostic biosensors is another interesting field of aptamer technology. In this review, significant efforts related to development and applications of aptamer technologies in proteins and peptides sciences were considered to emphasis on the importance of aptamers in medicinal and clinical applications.


Assuntos
Aptâmeros de Peptídeos , Peptídeos/análise , Proteínas/análise , Técnica de Seleção de Aptâmeros/tendências , Animais , Aptâmeros de Peptídeos/química , Aptâmeros de Peptídeos/metabolismo , Humanos , Camundongos , Peptídeos/química , Peptídeos/metabolismo , Proteínas/química , Proteínas/metabolismo
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 152: 119-25, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26204505

RESUMO

A rapid, simple and inexpensive spectrofluorimetric sensor for determination of doxycycline based on its interaction with thioglycolic acid-capped cadmium telluride quantum dots (TGA/CdTe QDs) has been developed. Under the optimum experimental conditions, the sensor exhibited a fast response time of <10s. The results revealed that doxycycline could quench the fluorescence of TGA/CdTe QDs via electron transfer from the QDs to doxycycline through a dynamic quenching mechanism. The sensor permitted determination of doxycycline in a concentration range of 1.9×10(-6)-6.1×10(-5)molL(-1) with a detection limit of 1.1×10(-7)molL(-1). The sensor was applied for determination of doxycycline in honey and human serum samples.


Assuntos
Antibacterianos/análise , Antibacterianos/sangue , Compostos de Cádmio/química , Doxiciclina/análise , Doxiciclina/sangue , Pontos Quânticos/química , Telúrio/química , Tioglicolatos/química , Mel/análise , Humanos , Limite de Detecção , Pontos Quânticos/ultraestrutura , Espectrometria de Fluorescência/métodos
13.
Jundishapur J Nat Pharm Prod ; 8(4): 187-91, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24624212

RESUMO

BACKGROUND: Apoptosis or programmed cell death is an essential process for elimination of damaged cells. Also, induction of apoptosis is fundamental for treating cancer. Screening for agents that induce apoptosis in tumor cells help in the development of novel agents for cancer treatment. Numerous studies suggest that the exposure of tumor cells to statins can lead to cell death via two separate processes: apoptosis or necrosis. Severe fragmentation of DNA during apoptosis can be readily measured by the neutral comet assay. Migration of DNA fragments of apoptotic cells by the electrical field can produce comet-like images. OBJECTIVES: The aim of this study was to determine the type of cell death induced by lovastatin on human colon tumor cells by using the neutral comet assay and to evaluate the utility of this method for detection of apoptosis. MATERIALS AND METHODS: HT29 cells were grown in DMEM medium then exposed to different concentrations of lovastatin, and DNA fragmentation associated with apoptosis was detected by the neutral comet assay method. RESULTS: Lovastatin induced an apoptotic response in the HT29 cell line and produced a comet pattern similar to the positive control. CONCLUSIONS: This study showed that lovastatin can induce apoptosis in the HT29 cell line and confirmed the utility of comet assay for detection of apoptosis.

14.
J Contemp Dent Pract ; 13(4): 515-20, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23151702

RESUMO

AIM: The objective of this study was to determine the association between DIAGNOdent laser and caries detector dye in detection of the remaining caries in restorative cavities. MATERIALS AND METHODS: The sample consisted of 100 cavities prepared in patients referring to the Department of Restorative Dentistry of Mashhad Dental School. After confirming caries absence by tactile examination, the presence of any residual caries was determined by a laser fluorescence (LF) device (DIAGNOdent Pen) and then by caries detector dye. The data were analyzed through McNemar test. RESULTS: When the cut off value was considered as ≥13, both DIAGNOdent Pen and caries detector dye found 54 cavities as without caries and 12 cavities as carious. There were 32 teeth diagnosed as decayed only by the dye and two cases that were diagnosed as having residual caries only by the DIAGNOdent. The McNemar test revealed a significant difference in the diagnosis of residual caries between the two methods (p < 0.05), as well as significant differences between each method and tactile examination (p < 0.05). When the cut off value was set at ≥25, no significant difference was found between laser fluorescence and tactile examination in residual caries detection (p > 0.05). CONCLUSION: Both DIAGNOdent Pen and caries detector dye can be considered as adjuncts for detecting residual caries in prepared cavities. However, the use of laser fluorescence device can provide results that are more consistent with tactile examination, while relying on caries detector dye may result in excessive removal of tooth tissue, and thus increase the risk of pulpal exposure. CLINICAL SIGNIFICANCE: Incomparision with caries detector dye, Residual caries detection by DIAGNOdent Pen is more consistent with tactile examination.


Assuntos
Corantes , Cárie Dentária/diagnóstico , Lasers , Adulto , Preparo da Cavidade Dentária , Fluorescência , Humanos , Pessoa de Meia-Idade , Propilenoglicóis , Rodaminas , Estatísticas não Paramétricas
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