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1.
BMC Plant Biol ; 24(1): 151, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38418942

RESUMO

BACKGROUND: Cannabis is a historically, culturally, and economically significant crop in human societies, owing to its versatile applications in both industry and medicine. Over many years, native cannabis populations have acclimated to the various environments found throughout Iran, resulting in rich genetic and phenotypic diversity. Examining phenotypic diversity within and between indigenous populations is crucial for effective plant breeding programs. This study aimed to classify indigenous cannabis populations in Iran to meet the needs of breeders and breeding programs in developing new cultivars. RESULTS: Here, we assessed phenotypic diversity in 25 indigenous populations based on 12 phenological and 14 morphological traits in male and female plants. The extent of heritability for each parameter was estimated in both genders, and relationships between quantitative and time-based traits were explored. Principal component analysis (PCA) identified traits influencing population distinctions. Overall, populations were broadly classified into early, medium, and late flowering groups. The highest extent of heritability of phenological traits was found in Start Flower Formation Time in Individuals (SFFI) for females (0.91) Flowering Time 50% in Individuals (50% of bracts formed) (FT50I) for males (0.98). Populations IR7385 and IR2845 exhibited the highest commercial index (60%). Among male plants, the highest extent of Relative Growth Rate (RGR) was observed in the IR2845 population (0.122 g.g- 1.day- 1). Finally, populations were clustered into seven groups according to the morphological traits in female and male plants. CONCLUSIONS: Overall, significant phenotypic diversity was observed among indigenous populations, emphasizing the potential for various applications. Early-flowering populations, with their high RGR and Harvest Index (HI), were found as promising options for inclusion in breeding programs. The findings provide valuable insights into harnessing the genetic diversity of indigenous cannabis for diverse purposes.


Assuntos
Cannabis , Humanos , Feminino , Masculino , Cannabis/genética , Irã (Geográfico) , Melhoramento Vegetal , Fenótipo , Reprodução
2.
Soft Matter ; 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39283268

RESUMO

The cellular Potts model, also known as the Glazier-Graner-Hogeweg model, is a lattice-based approach by which biological tissues at the level of individual cells can be numerically studied. Traditionally, a square or hexagonal underlying lattice structure is assumed for two-dimensional systems, and this is known to introduce artifacts in the structure and dynamics of the model tissues. That is, on regular lattices, cells can assume shapes that are dictated by the symmetries of the underlying lattice. Here, we developed a variant of this method that can be applied to a broad class of (ir)regular lattices. We show that on an irregular lattice deriving from a fluid-like configuration, two types of artifacts can be removed. We further report on the transition between a fluid-like disordered and a solid-like hexagonally ordered phase present for monodisperse confluent cells as a function of their surface tension. This transition shows the hallmarks of a first-order phase transition and is different from the glass/jamming transitions commonly reported for the vertex and active Voronoi models. We emphasize this by analyzing the distribution of shape parameters found in our state space. Our analysis provides a useful reference for the future study of epithelia using the (ir)regular cellular Potts model.

3.
BMC Geriatr ; 24(1): 264, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38500036

RESUMO

BACKGROUND: One of the risk factors of diabetes is the pre-diabetes stage which is significantly prevalent in older people. Knowledge, attitude, and practice of the pre-diabetic stage are of great importance and can decrease complications. The present study aimed to determine the knowledge, attitude, and practice of the pre-diabetic older people. METHODS: This cross-sectional study was conducted from April 2022 to August 2022 on 219 pre-diabetic older people referring to Sina Hospital in Tabriz, one of the most populated cities in the northwest of Iran. Data were collected using questionnaires of Knowledge, Attitude, Practice-Prediabetes Assessment Questionnaire (KAP-PAQ). The data were analyzed by SPSS 21. RESULTS: The mean scores of knowledge (in the range of 0-17), attitude (in the range of -10, + 10), and practice (in the range of 0-26) were 1.72 ± 1.0, 2.24 ± 1.92, and 5.76 ± 2.61, respectively. The older people's knowledge and practice levels in the pre-diabetes stage were low and about 50% of them had negative views. According to the Spearman correlation test, there was a positive significant relationship between the older people's knowledge and practice (p < 0.001, r = 0.234). CONCLUSIONS: The older people in the pre-diabetes stage had low knowledge and attitude and a negative viewpoint towards correcting lifestyle on diet, exercising and physical activity, weight control, diagnostic and screening methods. Increased knowledge about pre-diabetes and strengthened positive attitude towards correcting lifestyle through counseling as well as empowering the pre-diabetic older people can increase the efficiency of pre-diabetes prevention and control programs and prevent its progression to the diabetes stage.


Assuntos
Diabetes Mellitus , Estado Pré-Diabético , Humanos , Idoso , Estado Pré-Diabético/diagnóstico , Estado Pré-Diabético/epidemiologia , Estado Pré-Diabético/terapia , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/terapia , Estilo de Vida , Inquéritos e Questionários
4.
BMC Public Health ; 24(1): 2163, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39123187

RESUMO

BACKGROUND: Considering the values and preferences of individuals who attempt to quit smoking is a crucial step in the development of smoking cessation technologies. This study aimed to explore preferences regarding smart smoking cessation technologies. METHODS: This parallel convergent mixed-methods study was conducted in two phases: quantitative and qualitative. In the quantitative phase, a cross-sectional study was conducted with 360 participants selected through stratified random sampling from technology-based smoking cessation clinics in Tabriz, Tehran, and Karaj cities in Iran. Data on demographic characteristics and preferences for smart smoking cessation technologies were collected using questionnaires and analyzed using descriptive statistics. In the qualitative phase, 25 users of these technologies were selected through purposeful and snowball sampling. The data were gathered through in-depth semistructured interviews and analyzed using qualitative content analysis with a conventional approach. Quantitative and qualitative data were integrated using the merging strategy and convergence model. RESULTS: The quantitative phase results indicated that the highest preference was related to wearing and using a smartwatch for smoking cessation and using mobile apps. In the qualitative phase, 17 subcategories were extracted and classified into 8 main categories: high effectiveness, better management of the smoking cessation process, personalized technology, safe and uncomplicated technologies, attractiveness and innovative design, scientific basis, mobile applications, and smart monitoring devices. CONCLUSION: By combining and integrating quantitative and qualitative results, it can be concluded that users are more interested in wearable technologies and interactive mobile applications. The findings of this study can assist smoking cessation technology developers in designing and improving their tools based on user needs and preferences to enhance their effectiveness and acceptability.


Assuntos
Preferência do Paciente , Pesquisa Qualitativa , Fumantes , Abandono do Hábito de Fumar , Humanos , Irã (Geográfico) , Abandono do Hábito de Fumar/psicologia , Abandono do Hábito de Fumar/métodos , Feminino , Masculino , Adulto , Estudos Transversais , Pessoa de Meia-Idade , Fumantes/psicologia , Fumantes/estatística & dados numéricos , Adulto Jovem , Aplicativos Móveis , Inquéritos e Questionários
5.
Biochem Genet ; 62(1): 18-39, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37394575

RESUMO

A new era of medical technology in cancer treatment is a directly specific modification of gene expression in tumor cells by nucleic acid delivery. Currently, the main challenge to achieving this goal is to find a non-toxic, safe, and effective strategy for gene transfer to cancer cells. Synthetic composites based on cationic polymers have historically been favored in bioengineering due to their ability to mimic bimolecular structures. Among them, polyethylenimines (PEIs) with superior properties such as a wide range of molecular weight and a flexible structure may propel the development of functional combinations in the biomedical and biomaterial fields. Here, in this review, we will focus on the recent progressions in the formulation optimization of PEI-based polyplex in gene delivery to treat cancer. Also, the effect of PEI's intrinsic characteristics such as structure, molecular weight, and positive charges which influence the gene delivery efficiency will be discussed.


Assuntos
Neoplasias , Polietilenoimina , Polietilenoimina/química , Técnicas de Transferência de Genes , Terapia Genética , Transfecção , Neoplasias/genética , Neoplasias/terapia
6.
BMC Plant Biol ; 23(1): 316, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37316783

RESUMO

With the rising demand for new cultivars of carnation, efficient transformation protocols are needed to enable the bioengineering of new traits. Here, we established a novel and efficient Agrobacterium-mediated transformation system using callus as the target explant for four commercial carnation cultivars. Leaf-derived calli of all cultivars were inoculated with Agrobacterium tumefaciens strain LBA4404 containing the plasmid pCAMBIA 2301 harboring genes for ß-glucuronidase (uidA) and neomycin phosphotransferase (nptII). Polymerase chain reaction (PCR) and histochemical assays confirmed the presence of uidA and ß-glucuronidase (GUS), respectively in transgenic shoots. The effect on transformation efficiency of medium composition and the presence of antioxidants during inoculation and co-cultivation was investigated. The transformation efficiency was increased in Murashige and Skoog (MS) medium lacking KNO3 and NH4NO3, and also in MS medium lacking macro and micro elements and Fe to 5% and 3.1% respectively, compared to 0.6% in full-strength medium. Transformation efficiency was increased dramatically to 24.4% across all carnation cultivars by the addition of 2 mg/l melatonin to nitrogen-depleted MS medium. Shoot regeneration was also doubled in this treatment. The establishment of this efficient and reliable transformation protocol can advance the development of novel carnation cultivars through molecular breeding approaches.


Assuntos
Dianthus , Melatonina , Agrobacterium tumefaciens/genética , Glucuronidase , Nitrogênio
7.
Cell Mol Neurobiol ; 43(5): 2309-2322, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36449154

RESUMO

Glioma is a malignancy of the central nervous system with a poor prognosis. Therefore, the elaboration of its molecular features creates therapeutic opportunities. Looking for the regulatory non-coding RNAs (lncRNAs and miRNAs) that are involved in glioma incidence/progression, RNA-seq analysis introduced upregulated ADAMTS9-AS1 as a bona fide candidate that sponges miR-128 and miR-150 and shows the negative correlation of expression with them. Then, RT-qPCR verified the upregulation of ADAMTS9-AS1 in glioma tissues and cell lines. Furthermore, dual-luciferase assay supported that cytoplasmic ADAMTS9-AS1 is capable of sponging miR-128 and miR-150, which are known as regulators of Ras/MAPK, PI3K, and Wnt pathways. Following the overexpression of ADAMTS9-AS1 in 1321N1 and U87 glioma cells, tyrosine kinase receptors (IGF1R and TrkC), as well as Wnt receptors (Lrp6 and Fzd) were upregulated, detected by RT-qPCR. Furthermore, downstream genes of both Ras/MAPK and Wnt pathways were upregulated. Finally following the ADAMTS9-AS1 overexpression, upregulation of Ras/MAPK and Wnt signaling pathways was verified through western blotting and Top/Fop flash assay, respectively. At the cellular level, ADAMTS9-AS1 overexpression brought about reduced sub-G1 cell population, increased proliferation rate, reduced apoptosis level, increased migration rate, shortened Bax/Bcl2 ratio, induced EMT, and stemness characteristics of transfected cells, detected by flow cytometry, MTT assay, scratch test, and RT-qPCR. Overall, these results introduced ADAMTS9-AS1 as an oncogene that upregulates Ras/MAPK and Wnt pathways through sponging of the miR-128 and miR-150 in glioma cells. The outcome of ADAMTS9-AS1 expression is more aggression of the glioma cells through increased EMT and stemness characteristics. These features candidate ADAMTS9-AS1 locus for glioma therapy. As a result, we discovered the oncogenic properties of ADAMTS9-AS1 in glioma cancer. It sponges miR-128 and miR-150 and subsequently overstimulates RAS/MAPK and Wnt signaling pathways, particularly at the receptors level. Thus, ADAMTS9-AS1 increases proliferation, migration, and stemness in glioma cell lines. A schematic representation showing the functional effect of ADAMTS9-AS1.


Assuntos
Glioma , MicroRNAs , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Proliferação de Células/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Glioma/patologia , Via de Sinalização Wnt/genética , Linhagem Celular Tumoral , Receptores Proteína Tirosina Quinases/metabolismo , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética , Proteína ADAMTS9/genética , Proteína ADAMTS9/metabolismo
8.
J Theor Biol ; 564: 111436, 2023 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-36828246

RESUMO

Local environmental interactions are a major factor in determining the success of a new mutant in structured populations. Spatial variations in the concentration of genotype-specific resources change the fitness of competing strategies locally and thus can drastically change the outcome of evolutionary processes in unintuitive ways. The question is how such local environmental variations in network population structures change the condition for selection and fixation probability of an advantageous (or deleterious) mutant. We consider linear graph structures and focus on the case where resources have a spatial periodic pattern. This is the simplest model with two parameters, length scale and fitness scales, representing heterogeneity. We calculate fixation probability and fixation times for a constant population birth-death process as fitness heterogeneity and period vary. Fixation probability is affected by not only the level of fitness heterogeneity but also spatial scale of resources variations set by period of distribution T. We identify conditions for which a previously a deleterious mutant (in a uniform environment) becomes beneficial as fitness heterogeneity is increased. We observe cases where the fixation probability of both mutant and resident types are more than their neutral value, 1/N, simultaneously. This coincides with exponential increase in time to fixation which points to potential coexistence of resident and mutant types. Finally, we discuss the effect of the 'fitness shift' where the fitness function of two types has a phase difference. We observe significant increases (or decreases) in the fixation probability of the mutant as a result of such phase shift.


Assuntos
Evolução Biológica , Seleção Genética , Dinâmica Populacional , Processos Estocásticos , Probabilidade , Mutação
9.
Br J Neurosurg ; 37(6): 1533-1543, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34979828

RESUMO

BACKGROUND: Immune checkpoint inhibitors (ICIs) are an emerging tool in the treatment of brain metastases (BMs), Stereotactic radiosurgery (SRS), traditionally used for BMs, elicits an immune brain response and can act synergistically with ICIs. We aim to investigate the efficacy of ICI administered with SRS and determine the impact of timing on BM response. METHODS: A systematical search was performed to identify potential studies concerning BMs managed with SRS alone or with SRS + ICI with relative timing administration (ICI concurrent with SRS, ICI nonconcurrent with SRS, SRS before ICI, SRS after ICI). The overall survival (OS), 12-month OS, local progression-free survival (LPFS), 12-month local brain control (LBC), distant progression-free survival (DPFS), 12-month distant brain control (DBC), and adverse events (intracranial hemorrhage, radionecrosis) were analyzed using the random-effects model. RESULTS: A total of 16 retrospective studies with 1356 BM patients were included. Compared to nonconcurrent therapy, concurrent therapy revealed a significantly longer OS (HR= 1.43; p = 0.008) and 12-months LBC (HR = 1.91; p = 0.04), a similar 12-months DBC (HR = 1.12; p = 0.547) and higher complication rate (R = 0.77; p = 0.346). Concurrent therapy leads to a significantly higher OS compared to ICI before SRS (HR = 2.55; p = 0.0003). CONCLUSION: The combination of SRS with ICI improves patients' clinical and radiological outcomes. The effectiveness of the combination is subject to the identification of an optimal therapeutic window.


Assuntos
Neoplasias Encefálicas , Melanoma , Radiocirurgia , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Melanoma/secundário , Estudos Retrospectivos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia
10.
J Cell Biochem ; 123(4): 746-758, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35060166

RESUMO

HER2 signaling upregulation is a hallmark of breast cancer which is the second cause of cancer-related death in women. Here, we were looking for the candidate microRNAs which is capable of regulating the HER2 receptor and the genes of its downstream. To this aim, preliminary bioinformatics analysis introduced hsa-miR-1254 (miR-1254) as a potential common regulator of HER2, HER3, PIK3R2, and AKT1 genes. Then, reverse-transcription quantitative polymerase chain reaction (RT-qPCR) analysis indicated a lower expression level of miR-1254 in breast cancer specimens, compared to their normal pairs. Furthermore, overexpression of miR-1254 resulted in HER2, HER3, PIK3R2, and AKT1 genes downregulation, detected by RT-qPCR and confirmed by western blot analysis and enzyme-linked immunosorbent assay test against AKT1, BAX, FADD, and HER2 protein levels in SKBR3 cells. Dual-luciferase assay also supported direct interaction of miR-1254 with MREs within 3' untranslated region sequences of HER2, HER3, PIK3R2, and AKT1 target genes. Overexpression of miR-1254 in SKBR3 cells was followed by increased BAX/BCL2 expression ratio, detected by RT-qPCR, and increased proportion of G1 cell population, detected by flow cytometry. Corroborated by cell cycle analysis, MTT, Annexin V-FITC, and Live-Dead cell staining assays, overexpression of miR-1254 in MDA-MB-231 cells showed opposing results following the overexpression of miR-1254. Taken together, results indicated that miR-1254 acts as cell-type-specific tumor suppressor that targets HER2, HER3, PIK3R2, and AKT1 transcripts. These results suggest miR-1254 as a potential therapeutic candidate for breast cancer subtypes.


Assuntos
Neoplasias da Mama , MicroRNAs , Regiões 3' não Traduzidas , Neoplasias da Mama/metabolismo , Feminino , Humanos , MicroRNAs/genética , Receptor ErbB-2 , Transdução de Sinais/genética , Proteína X Associada a bcl-2/genética
11.
J Neurooncol ; 158(1): 1-13, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35460500

RESUMO

PURPOSE: LncRNAs play essential roles in the cellular and molecular biology of glioma. Some LncRNAs exert their role through sponging miRNAs and regulating multiple signaling pathways. LINC02381 is involved in several cancer types as either oncogene or tumor suppressor. Here, we intended to find the molecular mechanisms of the LINC02381 effect during the glioma progression in related cell lines. METHODS AND RESULTS: RNA-seq data analysis indicated the oncogenic characteristics of LINC02381, and RT-qPCR results confirmed its upregulation compared to normal tissues. Besides its expression was relatively stronger in invasive glioma cell lines. Furthermore, in silico analysis revealed LINC02381 is concentrated in the cytoplasm and predicted its sponging effect against miR-128 and miR-150, which was verified through dual luciferase assay. When LINC02381 was overexpressed in 1321N1, U87, and A172 cell lines, IGF1R and TrkC receptors as well as their downstream pathways (PI3K and RAS/MAPK), were upregulated, detected by RT-qPCR, and verified by western analysis. Consistently, LINC02381 overexpression was followed by an increased proliferation rate of transfected glioma cell lines, detected by flow cytometry and MTT assay, and RT-qPCR. It also resulted in elevated EMT and stemness markers expression level, increased migration rate, and reduced apoptosis rate, detected by RT-qPCR, western analysis, scratch test, and Annexin/PI flow cytometry analysis, respectively. CONCLUSION: The overall results indicated that LINC02381 exerts its oncogenic effect in glioma cells through sponging miR-128 and miR-150 to upregulate the IGF1R signaling pathway. Our results introduce LINC02381 and miR-128, and miR-150 as potential prognosis and therapy targets for the treatment of glioma.


Assuntos
Neoplasias Encefálicas , Glioma , MicroRNAs , RNA Longo não Codificante , Receptor IGF Tipo 1 , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Carcinogênese/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Glioma/genética , Glioma/metabolismo , Glioma/patologia , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Oncogenes , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Transdução de Sinais
12.
Chem Biodivers ; 18(4): e2001044, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33764630

RESUMO

Mentha longifolia L. is well-known to be one of the most pervasive wild-growing species of the Lamiaceae family, which has extensive beneficial properties in the fields of pharmacology and biological products. In the present study, the correlation between Inter-simple sequence repeat (ISSR) markers and morpho-chemical parameters of twenty different M. longifolia accessions (MLACs) were assessed. The geographic information system (GIS) has been employed to interpret the original habitat of the accessions in Iran. ISSR analysis indicated a remarkable difference in the studied accessions, segregated them into three main groups, constructed by an unweighted pair-group method with arithmetic (UPGMA) and principal coordinate analysis (PCoA). A total of 89 bands were generated by 12 ISSR primers, among which 82 (91.97 %) of them were polymorphic. The cluster analysis based on agro-morphological data scattered MLACs into two main groups. The essential oils (EOs) were analyzed through GC/FID/MS, and four chemotypes were characterized according to the major constituents. Pulegone ranged from 0.17 to 69.50 % was the main oil constituent with the highest content. Also, HPLC-PDA was employed to identify and to quantify the phenolic compounds in the MeOH extracts of MLACs. Heatmap cluster based on phenolic compounds produced three main categories of accessions. The components identified in the extracts were rosmarinic acid, rutin, vanillic acid, ferulic acid, chlorogenic acid, caffeic acid, 3,4-dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid, and p-coumaric acid, which among them rosmarinic acid (RA) varied from 39.16 to 261.55 mg/100 g (DW) as a predominant constituent. Subsequently, multiple regression analyses between ISSR fragments and morpho-chemical data illustrated considerable relationships in the plant materials. The high variation and correlation observed in metabolic and phenotypic traits of MLACs establish an adequate source to conduct reserves conservation programs.


Assuntos
Mentha/química , Óleos Voláteis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Análise por Conglomerados , Variação Genética/genética , Irã (Geográfico) , Mentha/genética , Óleos Voláteis/química , Filogenia , Extratos Vegetais/química , Extratos Vegetais/genética
13.
Psychiatr Q ; 91(4): 1407-1413, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32418140

RESUMO

Non-suicidal self-injury (NSSI) among adolescents is a major health concern globally. The epidemiology and determinant of NSSI have not been studied extensively in Iran. Thus, this longitudinal study sought to investigate the prevalence, incidence and contributing factors of NSSI among adolescents in Iran. This study was conducted at high school students aged 14-18 years old in the metropolitan city of Tabriz, located in north western Iran. Data were collected from 6229 10th-grade students at two time-points, with 12 months interval in October and November 2017 and 2018. A self-administered questionnaire was used to collect information on demographic, NSSI and cigarette and hookah smoking from the study participants. The results showed that lifetime prevalence of NSSI among students was 6.2% (95% confidence interval [CI]: 5.7 to 6.9) at the first assessment. Scratching and hair pulling were the most and least common methods of self-injury, respectively. Over the one year, 206 students (3.6% CI 95%: 3.1-4.1) reported the onset of NSSI. Tobacco smoking and previous year average grade were related to the incidence of NSSI. Although gender was significantly associated with the prevalence of NSSI, the relationship between gender and incidence of NSSI was not significant. Although the prevalence of NSSI was low among adolescents, the incidence rate was considerable. Further studies are required to understand the risk factors of NSSI in Iran.


Assuntos
Comportamento Autodestrutivo/epidemiologia , Comportamento Autodestrutivo/psicologia , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Adolescente , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Estudos Longitudinais , Masculino , Prevalência , Fatores de Risco , Instituições Acadêmicas
15.
Chemphyschem ; 16(9): 1852-6, 2015 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-26097118

RESUMO

Stimuli-directed alignment control of liquid crystals (LCs) with desired molecular orientation is currently in the limelight for the development of smart functional materials and devices. Here, photoresponsive azo thiol (AzoSH) was grafted onto gold nanoparticles (GNPs). The resulting hybrid GNPs were able to homogeneously mix with a commercially available nematic LC host, as evidenced by Cryo-TEM. Interestingly, the LC nanocomposites were found to undergo reversible alignment transition upon light irradiation as a consequence of the trans-cis photoisomerization of the azo groups on the GNP surface. LC molecules in either planar or bare glass cells were able to change their alignment to vertical upon UV irradiation, while the vertically aligned LC molecules returned to the planar or random orientation under visible irradiation. Neither the azo thiol molecules nor the unfunctionalized GNPs alone promoted the alignment of the LC molecules in the system upon light irradiation. The photoinduced vertical alignment without applied electric or magnetic field was very stable over time and with respect to temperature. Furthermore, an optically switchable device based on the photostimulated reversible alignment control of LCs was demonstrated.

16.
Soft Matter ; 11(6): 1208-13, 2015 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-25567417

RESUMO

We experimentally observed that the photonic band gap (reflection band) of polymer stabilized cholesteric liquid crystals with negative dielectric anisotropies can be greatly broadened under DC electric fields. We explored the underlying mechanism. We found that the dispersed polymer network moved when DC voltages were applied across the liquid crystal cell. The motion of the polymer network stretched the helical pitch of the liquid crystal on one side of the cell and compressed the helical pitch on the other side of the cell. We proposed a phenomenological theory to explain the motion of the polymer network and the effect of the polymer network on the helical pitch, and this theoretical prediction agreed well with the experimental results.

17.
Heliyon ; 10(17): e36768, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39263128

RESUMO

Gibberellic acid (GA3) is inhibitory to floral development of in vitro cannabis plants and inhibiting GA3 biosynthesis promotes floral development. As such, paclobutrazol (PBZ), a potent GA3 biosynthesis inhibitor may be useful for increasing floral biomass and expediting development, but due to health concerns, its use is prohibited in cannabis production. The present study was conducted to compare the use of PBZ with tannic acid (TA), a natural compound with potential GA3 inhibiting characteristics. Results confirmed that PBZ significantly affected the number of flowers, percentage of flowering plantlet, and flower appearance time. Treatment using PBZ at a concentration of 10 µM resulted in the greatest number of flowers (7.95) compared to other treatments. Moreover, this compound at concentrations of 5 and 10 µM yielded the highest percentage of flowering plantlets, at 75 % and 70 %, respectively. Flowers also appeared 7-15 days sooner than other treatments. Additionally, the energy transfer efficiency in the photosynthetic system and chlorophyll concentration in plants treated with PBZ were considerably higher than those under other treatments. Under the PBZ treatment, the length of internode was significantly reduced. In contrast, TA generally had the opposite effect of PBZ, suggesting that it does not act as a GA3 inhibitor in this context. Furthermore, positive effects of TA at a concentration of 10 µM were observed on total leaf area (840.08 mm2) and stem length (40.09 mm). The highest number of leaves (12.5) was found in the presence of TA at a concentration of 100 µM. TA at its highest concentration (1000 µM) had an inverse effect on cannabis growth and flowering but was likely due to toxicity rather than any inhibitory effects. Consequently, the obtained results confirm the importance of growth regulators and natural compounds on plant growth and can broaden our understanding for future research and achievement of objectives.

18.
Int Immunopharmacol ; 125(Pt A): 111101, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37922568

RESUMO

There are multiple treatment strategies that have been reported for breast cancer, while new and effective therapies against it are still necessary. Stimulating the immune system and its components against cancer cells is one of the unique treatment strategies of immunotherapy and long dsRNAs are immunostimulant in this regard. Based on bioinformatics approaches, a fragment of the Rice ragged stunt RNA virus genome was selected and synthesized according to its immunogenicity. Based on the in vitro transcription technique, dsRNA was synthesized and its binding ability to the PEI/PEI-Ac Polyethylenimine (PEI) or Acetylated polyethylenimine (PEI-Ac) was verified by the gel retardation assay. Then, the PEI-Ac was synthesized by adding acetyl groups to the PEI, and the results of the 1H NMR method indicated its successful synthesis. After cancer induction by 4 T1 cells in Balb/C mice, intraperitoneal (IP) and intratumoral (IT) treatment by the PEI/PEI-Ac-dsRNA were performed and the tumor growth inhibition was evaluated. Results demonstrated that PEI/PEI-Ac-dsRNA can lead to a decrease in tumor weight and volume in both the IP and IT routes. Also, by using macro-metastatic nodule counting and hematoxylin and eosin (H&E) staining we showed that PEI/PEI-Ac-dsRNA can prevent micro and macro-metastasis in the lung. Therefore, the PEI/PEI-Ac-dsRNA acts as an effective inhibitor of growth and metastasis of the breast cancer models. We showed that viral dsRNA can exert its antitumor properties by stimulating TNF-α and IFN-γ. In general, our results revealed that dsRNA derived from the plant virus genome stimulates the intrinsic immune system and can be a potential immune stimulant drug for cancer treatment.


Assuntos
Adjuvantes Imunológicos , Neoplasias , Animais , Camundongos , Polietilenoimina , RNA de Cadeia Dupla
19.
Crit Rev Oncol Hematol ; 186: 104015, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37146702

RESUMO

To determine the efficacy of stereotactic radiosurgery (SRS) in treating patients with brain metastases (BMs), a network meta-analysis (NMA) of randomized controlled trials (RCTs) and a direct comparison of cohort studies were performed. Relevant literature regarding the effectiveness of SRS alone and in combination with whole-brain radiotherapy (WBRT) and surgery was retrieved using systematic database searches up to April 2019. The patterns of overall survival (OS), one-year OS, progression-free survival (PFS), one-year local brain control (LBC), one-year distant brain control (DBC), neurological death (ND), and complication rate were analyzed. A total of 18 RCTs and 37 cohorts were included in the meta-analysis. Our data revealed that SRS carried a better OS than SRS+WBRT (p = 0.048) and WBRT (p = 0.041). Also, SRS+WBRT demonstrated a significantly improved PFS, LBC, and DBC compared to WBRT alone and SRS alone. Finally, SRS achieved the same LBC as high as surgery, but intracranial relapse occurred considerably more frequently in the absence of WBRT. However, there were not any significant differences in ND and toxicities between SRS and other groups. Therefore, SRS alone may be a better alternative since increased patient survival may outweigh the increased risk of brain tumor recurrence associated with it.


Assuntos
Neoplasias Encefálicas , Radiocirurgia , Humanos , Radiocirurgia/efeitos adversos , Irradiação Craniana , Neoplasias Encefálicas/secundário , Intervalo Livre de Progressão , Estudos de Coortes , Estudos Retrospectivos
20.
Appl Opt ; 50(17): 2701-7, 2011 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-21673775

RESUMO

A holographic technique for fabricating an electrically switchable liquid crystal/polymer composite Fresnel lens is reported. A Michelson interferometer is used to produce the required Fresnel pattern, by placing a convex lens into one path of the interferometer. Simplicity of the method and the possibility of fabricating different focal length lenses in a single arrangement are advantages of the method. The performance of the fabricated lens was demonstrated and its electro-optical properties were investigated for its primary focal length.

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