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1.
Expert Rev Clin Immunol ; 19(3): 329-339, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36706462

RESUMO

INTRODUCTION: Genetic defects affect the manner of the immune system's development, activation, and function. Nuclear factor-kappa B subunit 1 (NF-κB1) and NF-κB2 are involved in different biological processes, and deficiency in these transcription factors may reveal clinical and immunological difficulties. AREAS COVERED: This review article gathers the most frequent clinical and immunological remarkable characteristics of NF-κB1 and NF-κB2 deficiencies. Afterward, an effort is made to describe the biological mechanism, which is likely to be the cause of these clinical and immunological abnormalities. EXPERT OPINION: The present review article has explained the mechanism of contributions of the NF-κB1 and NF-κB2 deficiency in revealing immunodeficiency symptoms, specifically immunological and clinical manifestations. These mechanisms demonstrate the importance of NF-κB1 and NF-κB2 signaling pathways for B and T cell development, activation, antibody production, and immunotolerance. The manifestation of a mutation can range from no symptoms to severe complications in a family.


NF-κB1 and NF-κB2 are the transcription factors that have an essential role in the development and function of the immune system. Several mutations in the NF-κBs could lead to inborn errors of immune manifestations.There are different reports of NF-κB mutations with various clinical and immunological manifestations, whereas the mechanisms behind the appearance of these have been less discussed. We collected frequent clinical and immunological manifestations from the literature and discussed the likely biological cause of their occurrence. Here we clarify the potential mechanism that defects in NF-κB1 and NF-κB2 signaling lead to inadequate B and T cells function, specifically, insufficient switched memory B cells and class-switched antibodies and autoimmunity. We also focused on the straight correlation between deficiencies in immune system responses caused by defects in NF-κB and susceptibility to recurrent infections and other clinical problems.Since our understanding of the mechanisms of signaling pathways such as NF-κB deficiencies from genetic mutations to clinical manifestations in PIDs is limited, further in vitro and animal model studies are necessary to assess these pathways' comprehensive roles in immunodeficiency more accurately. [Figure: see text].


Assuntos
Síndromes de Imunodeficiência , NF-kappa B , Humanos , NF-kappa B/metabolismo , Subunidade p52 de NF-kappa B/genética , Subunidade p52 de NF-kappa B/metabolismo , Incidência , Subunidade p50 de NF-kappa B , Síndromes de Imunodeficiência/epidemiologia , Síndromes de Imunodeficiência/genética
2.
J Basic Microbiol ; 63(9): 1007-1015, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36086811

RESUMO

The aim of this study was to investigate the effect of zinc oxide nanoparticles (ZnO-NPs) on the expression of genes involved in toxin-antitoxin (TA) systems in multidrug-resistant (MDR) Acinetobacter baumannii. Seventy clinical isolates of A. baumannii were collected from variuos clinical samples. Antimicrobial susceptibility test was determined by disk diffusion. Type II TA system-related genes including GNAT, XRE-like, hipA, hipB, hicA, hicB were screened using polymerase chain reaction (PCR). ZnO-NPs prepared and characterized by field emission scanning electron microscopy and X-ray diffraction. MIC of ZnO-NPs of A. baumannii isolates was performed using the microdilution method. The expression of type II TA systems-related genes were assessed with and without exposure to ZnO-NPs using real-time PCR. The highest rate of resistance and sensitivity was observed against cefepime (77.14%), and ampicillin/sulbactam (42.85%), respectively. All A. baumannii isolates were considered as MDR. In this study, three TA loci were identified for A. baumannii including GNAT/XRE-like, HicA/HicB, and HipA/HipB and their prevalence was 100%, 42%, and 27.1%, respectively. There was no significant relationship between the prevalence of these systems and the origin of A. baumannii. Our data showed significant correlations between the presence of HicA/HicB system and resistance to ceftazidime, meropenem, imipenem, and cefepime (p < 0.05), and the presence of HipA/HipB system and resistance to ceftazidime, meropenem, imipenem, and cefepime (p < 0.05). In presence of ZnO-NPs, the expression of all studied genes decreased. GNAT and hicB showed the highest and lowest expression changes by 2.4 folds (p < 0.001) and 1.3 folds (p < 0.05), respectively. This study demonstrates the promising potential of nanoparticles to impact the expression of the genes involved in TA Systems. So, the application of ZnO-NPs may be helpful to design target-based strategies towards MDRs pathogens for empowered clinical applications by microbiologists and nanotechnologists.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Nanopartículas , Sistemas Toxina-Antitoxina , Óxido de Zinco , Humanos , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Óxido de Zinco/farmacologia , Ceftazidima/metabolismo , Ceftazidima/farmacologia , Cefepima/metabolismo , Cefepima/farmacologia , Meropeném/metabolismo , Meropeném/farmacologia , Imipenem/metabolismo , Imipenem/farmacologia , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana Múltipla/genética
3.
J Educ Health Promot ; 10: 310, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34667810

RESUMO

BACKGROUND: A doctor-patient relationship built on the concept of empathy is so essential to attain the best clinical outcomes in medicine. Since empathy has a positive role in interpersonal relationships and medical outcomes, its assessment is highly crucial. The aim of this study was to assess the empathy in last-year medical students using the Persian version of the Jefferson Scale of Physician Empathy (JSPE) and correlate empathy scores with demographic features. MATERIALS AND METHODS: In this cross-sectional study, last-year medical students at Shiraz Medical School, Shiraz, Iran, were recruited for this study. In this research, we used the Persian version of JSPE. The validity and reliability of the Persian version of this tool were confirmed in the previous research. For the analysis of data, we employed descriptive statistics and the independent sample t-test. RESULTS: One hundred and eighty-five final-year medical students were included in this study. The maximum score of the questionnaire was 140, and the total mean score of empathy was 98.15 ± 13.29. The females' total mean score (102.05 ± 11.89) was higher than the males' score (93.57 ± 13.46). The difference between the mean score of gender and empathy was significant (P value <.001), but there was no significant difference between empathy and the two other demographic factors (P > 0.05). CONCLUSIONS: Although physicians would gain the essential characteristics of empathy during their career, attending professors and other responsible policymakers in medical education should focus more on the factors related to physicians' empathy to train better and more professional physicians.

4.
J Biotechnol ; 259: 30-38, 2017 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-28827102

RESUMO

BACKGROUND: Human fibroblast growth factor-1 (FGF-1) has powerful mitogenic activities in a variety of cell types and plays significant roles in many physiological processes e.g. angiogenesis and wound healing. There is increasing demand for large scale production of recombinant human FGF-1 (rhFGF-1), in order to investigate the potential medical use. In the present study, we explored SHuffle™ T7 strain for production of rhFGF-1. METHODS: A synthetic gene encoding Met-140 amino acid form of human FGF-1 was utilized for expression of the protein in three different E. coli hosts (BL21 (DE3), Rosetta-gami™ 2(DE3), SHuffle™ T7). Total expressions and soluble/insoluble expression ratios of rhFGF-1 in different hosts were analyzed and compared. Soluble rhFGF-1 produced in SHuffle™ T7 cells was purified using one-step heparin-Sepharose affinity chromatography and characterized by a variety of methods for physicochemical and biological properties. RESULTS: The highest level of rhFGF-1 expression and maximum soluble/insoluble ratio were achieved in SHuffle™ T7 strain. Using a single-step heparin-Sepharose chromatography, about 1500mg of purified rhFGF-1 was obtained from one liter of the culture, representing purification yield of ∼70%. The purified protein was reactive toward anti-FGF-1 ployclonal antibody in immunoblotting. Mass spectrometry confirmed the protein had expected amino acid sequence and molecular weight. In reverse-phase high-performance liquid chromatography (RP-HPLC), the protein displayed the same retention time with the human FGF-1 standard, and purity of 94%. Less than 0.3% of the purified protein was comprised of oligomers and/or aggregates as judged by high-performance size-exclusion chromatography (HP-SEC). Secondary and tertiary structures of the protein, investigated by circular dichroism and intrinsic fluorescence spectroscopy methods, respectively, represented native folding of the protein. The purified rhFGF-1 was bioactive and stimulated proliferation of NIH 3T3 cells with EC50 of 0.84ng/mL. CONCLUSION: Although SHuffle™ T7 has been introduced for production of disulfide-bonded proteins in cytoplasm, we herein successfully recruited it for high yield production of soluble and bioactive rhFGF-1, a protein with 3 free cysteine and no disulfide bond. To our knowledge, this is the highest-level of rhFGF-1 expression in E. coli reported so far. Extensive physicochemical and biological analysis showed the protein had similar characteristic to authentic FGF-1.


Assuntos
Bacteriófago T7/genética , Fator 1 de Crescimento de Fibroblastos/química , Fator 1 de Crescimento de Fibroblastos/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Animais , Bacteriófago T7/metabolismo , Proliferação de Células/efeitos dos fármacos , Escherichia coli/genética , Fator 1 de Crescimento de Fibroblastos/genética , Fator 1 de Crescimento de Fibroblastos/farmacologia , Humanos , Camundongos , Células NIH 3T3 , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia
5.
Curr Med Chem ; 23(22): 2380-93, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27109576

RESUMO

Telomerase is a ribonucleoprotein enzyme, which has a significant role in synthesizing DNA telomeric in eukaryotes. Telomere maintenance can cause to immortalization and malignant transformation of human cells and thereby telomerase activity must be scrutinized as an important factor in most tumor cells. The proliferation of cancer cells or apoptosis induction can be suppressed by telomerase inhibition using different therapeutic agents without any side effects upon normal cells. Natural substances, with anti-tumor effects, such as those derived from plants can be suitable candidates due to their capabilities in preventing some side effects and resistance of tumors with respect to most chemotherapeutic drugs. In this regards, many studies have shown that natural phytochemicals have inhibitory effects on telomerase activity through affecting its subunits and components. Therefore, the aim of this paper is to review the recent studies on these kinds of phytochemicals in terms of property and mechanism. Moreover, strategies for improving the therapeutic efficacy of plant-derived substances such as combination therapy and nanoformulation based approaches are included.


Assuntos
Neoplasias/tratamento farmacológico , Telomerase/metabolismo , Anticarcinógenos/química , Anticarcinógenos/metabolismo , Anticarcinógenos/uso terapêutico , Catequina/análogos & derivados , Catequina/química , Catequina/metabolismo , Catequina/uso terapêutico , Curcumina/química , Curcumina/metabolismo , Curcumina/uso terapêutico , Composição de Medicamentos , Humanos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/metabolismo , Compostos Fitoquímicos/uso terapêutico , Polifenóis/química , Polifenóis/metabolismo , Polifenóis/uso terapêutico , Telomerase/antagonistas & inibidores
6.
Asian Pac J Cancer Prev ; 14(6): 3449-53, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23886126

RESUMO

BACKGROUND: Telomerase has been considered as an attractive molecular target for breast cancer therapy. The main objective of this work is to assess the inhibitory effects of silibinin and curcumin, two herbal substances, on telomerase gene expression in breast cancer cells. MATERIALS AND METHODS: For determination of cell viability tetrazolium-based assays were conducted after 24, 48, and 72 h exposure times and expression of human telomerase reverse transcriptase gene was measured with real-time PCR. RESULTS: Each compound exerted cytotoxic effects on T47D cells and inhibited telomerase gene expression, both in a time-and dose-dependent manner. The mixture of curcumin and silibinin showed relatively more inhibitory effect on growth of T47D cells and hTERT gene expression as compared with either agent alone. CONCLUSIONS: These findings suggest that cell viability along with hTERT gene expression in breast cancer cells could be reduced by curcumin and silibinin.


Assuntos
Neoplasias da Mama/enzimologia , Curcumina/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Silimarina/farmacologia , Telomerase/antagonistas & inibidores , Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Silibina , Telomerase/genética , Telomerase/metabolismo , Células Tumorais Cultivadas
7.
Asian Pac J Cancer Prev ; 14(11): 6925-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24377627

RESUMO

BACKGROUND: Despite numerous useful anticancer properties of curcumin, its utility is limited due to its hydrophobic structure. In this study, we investigated the comparative antiproliferative effect of PAMAM encapsulating curcumin with naked curcumin on the T47D breast cancer cell line. MATERIALS AND METHODS: Cytotoxic effects of PAMAM dendrimers encapsulating curcumin and curcumin alone were investigated by MTT assay. After treating cells with different concentrations of both curcumin alone and curcumin encapsulated for 24h, telomerase activity was determined by TRAP assay. RESULTS: While PAMAM dendrimers encapsulating curcumin had no cytotoxicity on cancer cells, they decreased the IC50 for proliferation and also increased the inhibitory effect on telomerase activity. CONCLUSIONS: Considering the non-toxicity in addition to effectiveness for enhancing curcumin anticancer properties, dendrimers could be considered good therapeutic vehicles for this hydrophobic agent.


Assuntos
Antineoplásicos/farmacologia , Materiais Biocompatíveis/química , Neoplasias da Mama/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Curcumina/farmacologia , Dendrímeros/química , Telomerase/antagonistas & inibidores , Neoplasias da Mama/patologia , Feminino , Humanos , Células Tumorais Cultivadas
8.
Cytotechnology ; 64(6): 719-26, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22526491

RESUMO

Leptin plays the role of mitogenic factor in the breast carcinogenesis. Therefore, it could be considered as a target for breast cancer therapy. Leptin gene expression could be modulated by activation of estrogen receptors. Silibinin is an herbal compound with anti-cancer activity on prostate and colorectal cancers. Based on the fact that targeting of leptin can be considered as a novel strategy for breast cancer therapy, the aim of this study was the investigation of potentiality of silibinin for inhibition of leptin gene expression and secretion, and its link with expression of estrogen receptors. Cytotoxic effect of silibinin on T47D breast cancer cells was investigated by MTT assay test after 24, 48 and 72 h treatments with different concentrations of silibinin. The levels of leptin, estrogen receptor α and estrogen receptor ß genes expression was measured by reverse-transcription real-time PCR. The amount of secreted leptin in the culture medium was determined by ELISA. Data were statistically analyzed by one-way ANOVA test. Silibinin inhibits growth of T47D cells in a time and dose dependent manner. There was significant difference between control and treated cells in the levels of leptin, estrogen receptor ß expression levels and the quantity of secreted leptin was decreased in the treated cells in comparison to control cells. In conclusion, silibinin inhibits the expression and the secretion of leptin and in the future it might probably be a drug candidate for breast cancer therapy through leptin targeting.

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