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1.
Oncology ; 101(7): 415-424, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37231904

RESUMO

INTRODUCTION: Gastric cancer is one of the common causes of cancer-related death in the world. Neurotransmitters have recently been related to the proliferation of cancer cells, but the role of neurotransmitters in the progression of gastric cancer is still unexplored. The cross-talk between the nervous system and immune cells through serotonin and its receptors in the tumor microenvironment can impact tumor progress. Our purpose is to expose probable changes in serotonin receptors, acetylcholinesterase, and monoamine oxidase A gene expression in gastric cancer. METHODS: Transcript of serotonin receptors (5-HTR2A, 5-HTR2B, 5-HTR3A, 5-HTR7) and monoamine oxidase A genes in the peripheral blood mononuclear cells (40 patients and 40 control) and tissue (21 tumors and 21 normal adjacent tissues) were assessed. The gene expression was analyzed by quantitative real-time PCR using suitable primers. Statistical analysis was performed using appropriate software (REST, Prism). RESULTS: Significantly higher amounts of 5-HTR2A, 5-HTR2B, 5-HTR3A, 5-HTR7, and acetylcholinesterase gene transcripts were found in the peripheral blood of gastric cancer patients compared with healthy individuals. The expression of 5-HTR2B and 5-HTR3A genes was significantly higher (p = 0.0250, p = 0.0005, respectively) and the acetylcholinesterase gene was lower in the tissue of patients (p = 0.0119) compared with adjacent normal tissue. CONCLUSION: This study highlights the role of serotonin receptors in gastric cancer that might have suggestions for the development of novel therapeutics and defensive approaches that target factors associated with the link between the nervous system, cancer cells, and the tumor microenvironment.


Assuntos
Acetilcolinesterase , Neoplasias Gástricas , Humanos , Acetilcolinesterase/genética , Neoplasias Gástricas/genética , Microambiente Tumoral/genética , Leucócitos Mononucleares , Receptores de Serotonina/genética , Receptores de Serotonina/metabolismo , Expressão Gênica , Monoaminoxidase/genética
2.
BMC Microbiol ; 21(1): 315, 2021 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-34763672

RESUMO

BACKGROUND: Although recent studies have indicated that imbalance in the respiratory microbiome composition is linked to several chronic respiratory diseases, the association between the lung microbiome and lung cancer has not been extensively studied. Conflicting reports of individual studies on respiratory microbiome alterations in lung cancer complicate the matter for specifying how the lung microbiome is linked to lung cancer. Consequently, as the first meta-analysis on this topic, we integrate publicly available 16S rRNA gene sequence data on lung tissue samples of lung cancer patients to identify bacterial taxa which differ consistently between case and control groups. RESULTS: The findings of the current study suggest that the relative abundance of several bacterial taxa including Actinobacteria phylum, Corynebacteriaceae and Halomonadaceae families, and Corynebacterium, Lachnoanaerobaculum, and Halomonas genera is significantly decreased (p < 0.05) in lung tumor tissues of lung cancer patients in comparison with tumor-adjacent normal tissues. CONCLUSIONS: Despite the underlying need for scrutinizing the findings further, the present study lays the groundwork for future research and adds to our limited understanding of the key role of the lung microbiome and its complex interaction with lung cancer. More data on demographic factors and tumor tissue types would help establish a greater degree of accuracy in characterizing the lung microbial community which accords with subtypes and stages of the disease and fully capturing the changes of the lung microbiome in lung cancer.


Assuntos
Bactérias/isolamento & purificação , Neoplasias Pulmonares/microbiologia , Pulmão/microbiologia , Microbiota , Adulto , Idoso , Idoso de 80 Anos ou mais , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , DNA Bacteriano/genética , Feminino , Humanos , Masculino , RNA Ribossômico 16S/genética
3.
J Phys Chem A ; 124(25): 5089-5097, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32469520

RESUMO

We have conducted here a theoretical exploration, discussing the distinct excited state lifetimes reported experimentally for the two lowest lying protonated isomers of uracil. In this regard, the first-principal computational levels as well as the nonadiabatic surface hopping dynamics have been employed. It has been revealed that relaxation of the 1ππ* state of enol-enol form (EE+) to the ground is barrier-free via out-of-plane coordinates, resulting in an ultrashort S1 lifetime of this species. For the second most stable isomer (EK+), however, a significant barrier predicted in the CASPT2 S1 potential energy profile along the twisting coordinate has been proposed to explain the relevant long lifetime reported experimentally.

4.
J Phys Chem A ; 122(10): 2653-2662, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29489372

RESUMO

Thiazolo-[4,5- d]-thiazo-frame (tztz) compounds are important heteroaromatic organic systems, which recently became a subject of several studies in the field of organic electronics and organic photovoltaics. The most important physical nature of these systems is reported to be an equilibrium between enol and keto forms following excited-state proton transfer. This process originates from a flat trend of the S1 PE (potential energy) profile along the proton transfer coordinate. In the present work, we determined and interpreted the excited-state proton transfer and photophysical nature of these systems extensively by means of the MP2/CC2 and CASSCF theoretical approaches. Also, the effects of amine (-NH2) and cyano (-CN) substitutions were taken into account comprehensively by considering the transition energies and proton transfer pathways of the resulting tztz derivatives. It has been predicted that the physical nature of the excited-state intramolecular proton transfer, as the main character of these systems, is being affected significantly by substitutions. For all of the considered tztz derivatives, a conical intersection (CI) between ground and the S1 excited state was predicted. This CI makes the considered species capable to be responsible for photochromism and photoswitching as well.

5.
Exp Appl Acarol ; 75(1): 41-53, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29600387

RESUMO

The plant stress hypothesis posits that a herbivore's reproductive success increases when it feeds on stressed plants, while the plant vigor hypothesis predicts that a herbivore preferentially feeds on more vigorous plants. We examined these opposing hypotheses by growing spider mites (Tetranychus urticae) on the leaves of stressed and healthy (vigorous) cucumber plants. Host plants were grown under controlled conditions at low, moderate, and high concentrations of NaCl (to induce salinity stress), at low, moderate, and high fertilizer concentrations (to support growth), and without these additions (control). The effects of these treatments were evaluated by measuring fresh and dry plant biomass, carotenoid and chlorophyll content, antioxidant enzyme activity, and concentrations of PO43-, K+, and Na+ in plant tissues. The addition of low concentrations of fertilizer increased dry mass, protein, and carotenoid content relative to controls, suggesting a beneficial effect on plants. The highest NaCl treatment (2560 mg L-1) resulted in increased Na+ and protein content relative to control plants, as well as reduced PO43-, K+, and chlorophyll levels and reduced catalase and ascorbate peroxidase enzyme activity levels. Analysis of life table data of T. urticae mites raised on leaves from the aforementioned plant groups showed the intrinsic rate of increase (r) for mites was 0.167 day-1 in control specimens, 0.125 day-1 for mites reared on plants treated with a moderate concentration of fertilizer (10 mL L-1), and was highest (0.241 day-1) on plants grown under moderate salinity conditions (1920 mg L-1 NaCl). Reproductive success of T. urticae did not differ on plants watered with a moderate concentration of NaCl or a high concentration of fertilizer. The moderately-stressed plants formed a favorable environment for the development and reproduction of spider mites, supporting the plant stress hypothesis.


Assuntos
Cucumis sativus/fisiologia , Fertilizantes/análise , Salinidade , Tetranychidae/fisiologia , Animais , Feminino , Masculino , Crescimento Demográfico , Reprodução
6.
ACS Appl Mater Interfaces ; 16(3): 3019-3030, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38217858

RESUMO

Urease-powered nano/micromotors can move at physiological urea concentrations, making them useful for biomedical applications, such as treating bladder cancer. However, their movement in biological environments is still challenging. Herein, Janus micromotors based on black TiO2 with urease asymmetric catalytic coating were designed to take benefit of the optical properties of black TiO2 under near-infrared light and the movement capability in simulated bladder environments (urea). The black TiO2 microspheres were half-coated with a thin layer of Au, and l-Cysteine was utilized to attach the urease enzyme to the Au surface using its thiol group. Biocatalytic hydrolysis of urea through urease at biologically relevant concentrations provided the driving force for micromotors. A variety of parameters, such as urea fuel concentration, viscosity, and ionic character of the environment, were used to investigate how micromotors moved in different concentrations of urea in water, PBS, NaCl, and urine. The results indicate that micromotors are propelled through ionic self-diffusiophoresis caused by urea enzymatic catalysis. Due to their low toxicity and in vitro anticancer effect, micromotors are effective agents for photothermal therapy, which can help kill bladder cancer cells. These promising results suggest that biocompatible micromotors hold great potential for improving cancer treatment and facilitating diagnosis.


Assuntos
Urease , Neoplasias da Bexiga Urinária , Humanos , Terapia Fototérmica , Microesferas , Neoplasias da Bexiga Urinária/tratamento farmacológico , Ureia
7.
Cell Biochem Biophys ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38878101

RESUMO

One of the most prevalent types of cancer worldwide today is gastric intestinal (GI) tumors. To guarantee their lives, people with a developed GI require palliative care. This covers the application of targeted medicines in addition to chemotherapy treatments including cisplatin, 5-fluorouracil, oxaliplatin, paclitaxel, and pemetrexed. Because of the evidence of drug resistance emerging in poor patient outcomes and prognoses, determining the exact process of medication resistance is motivated. Besides, it is noteworthy that exosomes and noncoding RNAs, like microRNAs and long non-coding RNAs (lncRNAs), produced from tumor cells are implicated in both GI medication resistance and the carcinogenesis and development of GI disease. Biochemical events related to the cell cycle, differentiation of cells, growth, and pluripotency, in addition to gene transcription, splicing, and epigenetics, are all regulated by noncoding RNAs (ncRNAs). Therefore, it should come as a wonder that several ncRNAs have been connected in recent years to drug susceptibility and resistance as well as tumorigenesis. Additionally, through communicating directly with medications, altering the transcriptome of tumor cells, and affecting the immune system, exosomes may govern treatment resistance. Because of this, exosomal lncRNAs often act as a competitive endogenous RNA (ceRNA) of miRNAs to carry out its role in modifying drug resistance. In light of this, we provide an overview of the roles and processes of ncRNA-enriched exosomes in GI medication resistance.

8.
Curr Diabetes Rev ; 19(7): e031122210620, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36330635

RESUMO

Diabetes is one of the main causes of infertility, which impacts the quality of life of couples. These reproductive complications are important issues for all clinicians. The strategies for the treatment of diabetes-induced infertility are limited with the high cost and unsatisfied results. Due to the multi-directional differentiation potential and self-renewal ability of stem cells, these cells have emerged as attractive therapeutic agents in many diseases, including diabetes mellitus. We reviewed the current knowledge on the best available evidence regarding the role of stem cell transplantation in reproductive complications of diabetes.


Assuntos
Diabetes Mellitus , Infertilidade Masculina , Masculino , Humanos , Infertilidade Masculina/etiologia , Infertilidade Masculina/terapia , Qualidade de Vida , Diabetes Mellitus/terapia , Transplante de Células-Tronco/efeitos adversos
9.
Antioxidants (Basel) ; 11(9)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36139763

RESUMO

Zinc (Zn) and copper (Cu) are essential micronutrients for the plant's growth, development, and metabolism, but in high concentrations, the elements disrupt normal metabolic processes. The present study investigated the effects of different concentrations (added to a Hogland-based solution) of zinc (control, 5, 10 mg L-1 ZnSO4) and copper (control, 0.1, 0.2 mg L-1 CuSO4) on the growth characteristics and biochemical indices of summer squash (Cucurbita pepo L.). Compared with control, a single application of Cu or Zn at both concentrations significantly declined fruit yield, growth traits, pigments content, and high content of these minerals and values of stress-related indices. Increased Cu concentration in the nutritional solutions reduced the activity of ascorbate peroxidase (APX) and guaiacol peroxidase (GPX). Copper at high concentrations intensified ROS production, aggravated oxidative stresses, and decreased the plant yield and productivity. Nonetheless, combining Cu and Zn could alleviate stress intensity by boosting antioxidant enzymes, redox regulation, and a resultant diminishment in the content of H2O2, proline, malondialdehyde, and minerals. The obtained results corroborate that the co-application of zinc in Cu-contaminated areas can improve the plant's economic yield and physiological parameters by hindering copper toxicity and enhancing the photosynthetic capacity.

10.
Microrna ; 7(2): 74-84, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29380708

RESUMO

BACKGROUND: RNA interference (RNAi) and related pathways involving small interfering RNAs (siRNAs), microRNAs (miRNAs), and PIWI-interacting RNAs (piRNAs) regulate processes such as antiviral defense, genome surveillance, heterochromatin formation, and gene expression in animals, plants, and fungi. Studies on RNAi have revealed a two-step mechanism: (i) Degradation of dsRNA into small interfering RNAs (siRNAs), 21 to 25 nucleotides long, by an RNase III-like activity. (ii) The siRNAs join an RNase complex, RISC (RNA-induced silencing complex), which acts on the mRNA and degrades it. OBJECTIVE: Molecular structures of Dicer, Argonaute proteins, and RNA-bound complexes have offered insights into the underlying mechanisms of RNA-silencing pathways. METHODS: Sequence specific gene silencing using small interfering RNA (siRNA) is now being evaluated as a novel therapeutic strategy. RESULTS: Recently, promising data have been obtained from clinical trials for the treatment of respiratory syncytial virus and age-related macular degeneration. The exact mechanism of the RNAi pathways is still unclear. CONCLUSION: Our review summarizes the RNAi pathways and the known functions of siRNAs, miRNAs, and piRNAs in lower and higher organisms (mostly focusing on mammals) and discusses the potential applications of RNAi.


Assuntos
Inativação Gênica , Interferência de RNA , RNA Interferente Pequeno/fisiologia , Animais , Proteínas Argonautas/metabolismo , Humanos , Plantas/genética
11.
Iran J Nurs Midwifery Res ; 21(2): 202-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27095996

RESUMO

BACKGROUND: Premature neonates' feeding is of great importance due to its effective role in their growth. These neonates should reach an independent oral nutrition stage before being discharged from the Neonatal Intensive care Unit. Therefore, the researcher decided to conduct a study on the effect of palady and cup feeding on premature neonates' weight gain and their reaching full oral feeding time interval. MATERIALS AND METHODS: This is a clinical trial with a quantitative design conducted on 69 premature infants (gestational age between 29 and 32 weeks) who were assigned to cup (n = 34) and palady (n = 35) feeding groups through random allocation. The first feeding was administrated either by cup or palady method in each shift within seven sequential days (total of 21 cup and palady feedings). Then, the rest of feeding was administrated by gavage. RESULTS: Mean hospitalization time (cup = 39.01 and palady = 30.4; P < 0.001) and mean time interval to reach full oral feeding (cup = 33.7 and palady = 24.1; P < 0.001) were significantly lower in palady group compared to cup group. Mean weight changes of neonates 7 weeks after the intervention compared to those in the beginning of the intervention were significantly more in palady group compared to the cup group (cup = 146.7 and palady = 198.8; P < 0.001). CONCLUSIONS: The neonates in palady group reached full oral feeding earlier than those of cup group. Subjects' weight gain was also higher in palady group compared to the cup group. Premature neonates with over 30 weeks of gestational age and physiological stability can be fed by palady.

12.
Vet Ital ; 48(4): 405-12, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23277121

RESUMO

Brucellosis is one of the most important zoonotic diseases and is a significant cause of abortion in animals. Brucella melitensis strain Rev. 1 is recommended as the most effective vaccine for small ruminants but the application of full doses in adult animals is restricted. This study was conducted to determine a proper reduced dose of vaccine which confers protection but which is not abortifacient in Iranian fat-tailed sheep. A total of 51 non-vaccinated pregnant ewes were divided into three main groups and several subgroups. Ewes in different groups were vaccinated at different stages of pregnancy and various subgroups were subcutaneously immunised with different quantities of the micro-organism (7.5 × 10(6), 10(6), 5 × 10(5)). Ewes again became pregnant a year later and were challenged with the wild-type strain to evaluate the protection conferred. Results revealed that the proportion of vaccination-induced abortions was significantly higher in ewes immunised with 7.5 × 10(6) Rev. 1 organisms than in those which received 10(6) or 5 × 10(5) bacteria. While 80% of non-vaccinated ewes aborted after challenge, none of the vaccinated ewes aborted post-challenge. This study indicated that a reduced dose of Rev. 1 vaccine containing 10(6) or 5 × 10(5) live cells could be safely used to induce protection in Iranian fat-tailed sheep at various stages of pregnancy.


Assuntos
Vacinas Bacterianas/administração & dosagem , Brucelose/veterinária , Complicações Infecciosas na Gravidez/veterinária , Doenças dos Ovinos/prevenção & controle , Animais , Vacinas Bacterianas/efeitos adversos , Brucelose/prevenção & controle , Feminino , Irã (Geográfico) , Gravidez , Complicações Infecciosas na Gravidez/prevenção & controle , Ovinos
13.
Int J Nanomedicine ; 7: 4159-68, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22888250

RESUMO

PURPOSE: The failure of colorectal cancer treatments is partly due to overexpression of CXCR4 by tumor cells, which plays a critical role in cell metastasis. Moreover, serum alkaline phosphatase (ALP) levels are frequently elevated in patients with metastatic colorectal cancer. A polysaccharide, dextran, was chosen as the vector of siRNA. Spermine was conjugated to oxidized dextran by reductive amination process to obtain cationized dextran, so-called dextran-spermine, in order to prepare CXCR4-siRNAs/dextran-spermine nanoparticles. The fabricated nanoparticles were used in order to investigate whether downregulation of CXCR4 expression could affect serum ALP in mouse models of colorectal cancer. METHODS: Colorectal cancer was established in BALB/C mice following injection of mouse colon carcinoma cells CT.26WT through the tail vein. CXCR4 siRNA for two sites of the target gene was administered following injection of naked siRNA or siRNA encapsulated into nanoparticles. RESULTS: In vivo animal data revealed that CXCR4 silencing by dextran-spermine nanoparticles significantly downregulated CXCR4 expression compared with naked CXCR4 siRNA. Furthermore, there was correlation between CXCR4 expression and serum ALP. CONCLUSION: CXCR4 siRNA/dextran-spermine nanoparticles appear to be highly effective, and may be suitable for further in vivo applications. Further research evaluation will be needed to determine the effect of CXCR4 silencing on serum ALP levels, which may be a useful marker to predict liver metastasis in colorectal cancer.


Assuntos
Fosfatase Alcalina/sangue , Neoplasias Colorretais/metabolismo , Dextranos/química , Nanocápsulas/química , RNA Interferente Pequeno/química , Receptores CXCR4/biossíntese , Receptores CXCR4/genética , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Animais , Cátions/química , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Regulação para Baixo , Feminino , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Nanocápsulas/administração & dosagem , Tamanho da Partícula , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores CXCR4/metabolismo , Espermina/química
14.
Cancer Manag Res ; 3: 301-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21931504

RESUMO

Liver metastasis is the main cause of mortality related to colorectal cancer. CXCR4 is necessary for the outgrowth of colon cancer micrometastases. In oncology, it has been demonstrated that several human tumors release lactate dehydrogenase (LDH) into the circulation. CXCR4 gene expression and serum LDH levels are often increased in patients with colorectal cancer. Despite technological advances in cancer therapy, five-year overall survival is still around 50%. Therefore, better treatment needs to be developed. RNA interference (RNAi) is a modern and powerful tool for inhibition of gene expression. However, the rate-limiting step in this technology is effective delivery of RNAi agents. We have investigated a novel strategy of CXCR4 siRNA therapy and its effect on serum LDH levels in a BALB/C mouse model of colorectal cancer metastasis to the liver. Hepatic metastasis was established by injecting a CT26.WT mouse colon carcinoma cell line via the tail vein. Our results demonstrated that CXCR4 siRNA/ dextran-spermine nanoparticles achieved high silencing efficiency with low toxicity. Favorable localization of the nanoparticles was confirmed with CXCR4 gene expression in the liver, that was correlated with serum LDH levels. More research will be needed to determine the effect of CXCR4 silencing on serum LDH levels, which may be a useful marker for predicting liver metastasis in colorectal cancer.

15.
Pak J Biol Sci ; 10(18): 3146-9, 2007 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19090114

RESUMO

Endothelial progenitor cells from the pulp of milk teeth were isolated for use in clinical applications and tissue engineering. Normal deciduous teeth from children of 7 to 8 years of age, which more than half the tooth root was extracted, were selected from the dental centre. Cells from enzyme treated pulps were cultured and cells resulting from the fifth and eight subculture were combined for cell surface marker determination experiments. Cells were positive for CD34 marker with a total of 99/45%, determined by flowcytometry. Cells also demonstrated alkaline phosphatase (ALP) activity. From the developmental point of view, stem cells from the dental pulp seem to have derived from the neural crest, which our findings technically support this theory. In essence mobile progenitor cells from bone marrow of endothelial origin could also play a significant role in the derivation of dental pulp stem cells.


Assuntos
Fosfatase Alcalina/metabolismo , Antígenos CD34/biossíntese , Polpa Dentária/citologia , Células Endoteliais/citologia , Células-Tronco/citologia , Dente/citologia , Linhagem Celular , Células Cultivadas , Citometria de Fluxo , Humanos , Imuno-Histoquímica/métodos , Crista Neural/metabolismo , Células-Tronco/metabolismo
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