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1.
Sensors (Basel) ; 23(7)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37050835

RESUMO

Global concerns regarding environmental preservation and energy sustainability have emerged due to the various impacts of constantly increasing energy demands and climate changes. With advancements in smart grid, edge computing, and Metaverse-based technologies, it has become apparent that conventional private power networks are insufficient to meet the demanding requirements of industrial applications. The unique capabilities of 5G, such as numerous connections, high reliability, low latency, and large bandwidth, make it an excellent choice for smart grid services. The 5G network industry will heavily rely on the Internet of Things (IoT) to progress, which will act as a catalyst for the development of the future smart grid. This comprehensive platform will not only include communication infrastructure for smart grid edge computing, but also Metaverse platforms. Therefore, optimizing the IoT is crucial to achieve a sustainable edge computing network. This paper presents the design, fabrication, and evaluation of a super-efficient GSM triplexer for 5G-enabled IoT in sustainable smart grid edge computing and the Metaverse. This component is intended to operate at 0.815/1.58/2.65 GHz for 5G applications. The physical layout of our triplexer is new, and it is presented for the first time in this work. The overall size of our triplexer is only 0.007 λg2, which is the smallest compared to the previous works. The proposed triplexer has very low insertion losses of 0.12 dB, 0.09 dB, and 0.42 dB at the first, second, and third channels, respectively. We achieved the minimum insertion losses compared to previous triplexers. Additionally, the common port return losses (RLs) were better than 26 dB at all channels.

2.
Int J Mol Sci ; 24(6)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36982849

RESUMO

The higher heating value (HHV) is the main property showing the energy amount of biomass samples. Several linear correlations based on either the proximate or the ultimate analysis have already been proposed for predicting biomass HHV. Since the HHV relationship with the proximate and ultimate analyses is not linear, nonlinear models might be a better alternative. Accordingly, this study employed the Elman recurrent neural network (ENN) to anticipate the HHV of different biomass samples from both the ultimate and proximate compositional analyses as the model inputs. The number of hidden neurons and the training algorithm were determined in such a way that the ENN model showed the highest prediction and generalization accuracy. The single hidden layer ENN with only four nodes, trained by the Levenberg-Marquardt algorithm, was identified as the most accurate model. The proposed ENN exhibited reliable prediction and generalization performance for estimating 532 experimental HHVs with a low mean absolute error of 0.67 and a mean square error of 0.96. In addition, the proposed ENN model provides a ground to clearly understand the dependency of the HHV on the fixed carbon, volatile matter, ash, carbon, hydrogen, nitrogen, oxygen, and sulfur content of biomass feedstocks.


Assuntos
Calefação , Redes Neurais de Computação , Biomassa , Algoritmos , Carbono
3.
Endocr Pract ; 28(3): 342-348, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34838762

RESUMO

OBJECTIVES: To show that there is relation between neutrophil-to-lymphocyte ratio (NLR) and metabolic syndrome and also, its components. FINDINGS: Metabolic syndrome is associated with elevated fasting blood glucose, increased blood pressure, central obesity, decreased high-density lipoprotein, and increased triglyceride levels. Because of its growing incidence and prevalence and the effect that it has on developing other noncommunicable diseases, the importance gets even more value. The prediction and control of this disease in its early stages and in the most inexpensive way is of crucial need. Due to the role of chronic low-grade inflammation in metabolic syndrome, cytokines and inflammatory factors (like interleukin-6 and tumor necrosis factor-α) play a critical role on this phenomenon. The NLR is an inflammatory marker that has an unchallenging availability and has a reasonable cost. The NLR is related to obesity, type 2 diabetes, hypertension, and blood cholesterol levels. CONCLUSION: This suggests that there may be a relationship between the NLR and metabolic syndrome. The NLR, as a low-grade inflammation marker, indicates a positive relationship with central obesity. Also, studies indicate that the incidence of diabetes, its severity, and its control are related to the NLR. Hypertension and hyperlipidemia can both be noticed with higher NLRs. This rapid review assesses the association between metabolic syndrome and the NLR.


Assuntos
Diabetes Mellitus Tipo 2 , Síndrome Metabólica , Biomarcadores , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Linfócitos/metabolismo , Linfócitos/patologia , Síndrome Metabólica/metabolismo , Neutrófilos/metabolismo , Neutrófilos/patologia
4.
J Res Med Sci ; 27: 93, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36685020

RESUMO

Cancer is a primary cause of mortality around the world and imposes a significant physiological, psychological, and financial burden on patients. Lipids regulate cell cycle progression and affect cell proliferation, migration, and apoptosis. Therefore, alterations in serum lipid levels might contribute to carcinogenesis. In this article, we review the relationships between triglyceride (TG), total cholesterol, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) levels and different types of cancer. Then, we examine the association between cancer and familial hypercholesterolemia. Finally, we evaluate the impact of statins on different types of cancer. Increased total cholesterol has been reported to increase cellular proliferation and angiogenesis in tumors and inhibit apoptosis. Increased LDL-C has been reported to induce inflammation and increase susceptibility to oxidative damage. HDL-C has anti-oxidation, anti-inflammatory, and antiproliferative properties. Increased levels of serum TG can induce oxidative stress and a chronic inflammatory state and therefore contribute to the proliferation and progression of cancer cells. Statins decrease downstream products of cholesterol synthesis that are crucial in cell proliferation and growth. Thus, lipid components can have prognostic value in cancer and management of serum lipid levels through lifestyle changes and medical therapy can be beneficial in cancer prevention and treatment.

5.
J Cell Biochem ; 120(9): 16264-16272, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31111537

RESUMO

One of the most important molecules for multiple sclerosis pathogenesis is α4 integrin, which is responsible for autoreactive leukocytes migration into the brain. The monoclonal antibody, natalizumab, was introduced to market for blocking the extravasation of autoreactive leukocytes via inhibition of α4 integrin. However, the disadvantages of antibodies provided a suitable background for other agents to be replaced with antibodies. Considering the profound advantages of aptamers over antibodies, aptamer isolation against α4 integrin was intended in the current study. The α4 integrin-specific aptamers were selected using cell-systematic evolution of ligands by exponential enrichment (SELEX) method with human embryonic kidney (HEK)-293T overexpressing α4 integrin and HEK-293T as target and control cells, respectively. Evaluation of selected aptamer was performed through flow cytometric analysis. The selected clones were then sequenced and analyzed for any possible secondary structure and affinity. The results of this study led to isolation of 13 different single-stranded DNA clones in 11 rounds of selection which were categorized to three clusters based on common structural motifs and the equilibrium dissociation constant (K d ) of the most stable structure was calculated. The evaluation of SELEX progress showed growth in aptamer affinity with increasing of the number of cycles. Taken together, the findings of this study demonstrated the isolation of α4-specific single-stranded DNA aptamers with suitable affinity for ligand, which can further be replaced with natalizumab.


Assuntos
Aptâmeros de Nucleotídeos/genética , Integrina alfa4/química , Esclerose Múltipla/genética , Aptâmeros de Nucleotídeos/farmacologia , Células HEK293 , Humanos , Integrina alfa4/genética , Modelos Moleculares , Esclerose Múltipla/tratamento farmacológico , Conformação de Ácido Nucleico , Técnica de Seleção de Aptâmeros
6.
Cancer Immunol Immunother ; 67(3): 367-379, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29124314

RESUMO

Regulatory T cells (Treg) and myeloid-derived suppressor cells (MDSC) are the two important and interactive immunosuppressive components of the tumor microenvironment that hamper anti-tumor immune responses. Therefore, targeting these two populations together might be beneficial for overcoming immune suppression in the tumor microenvironment. We have recently shown that prophylactic Foxp3 DNA/recombinant protein vaccine (Foxp3 vaccine) promotes immunity against Treg in tumor-free conditions. In the present study, we investigated the immune modulatory effects of a prophylactic regimen of the redesigned Foxp3 vaccine in the B16F10 melanoma model. Our results indicate that Foxp3 vaccination continuously reduces Treg population in both the tumor site and the spleen. Surprisingly, Treg reduction was associated with a significant decrease in the frequency of MDSC, both in the spleen and in the tumor environment. Furthermore, Foxp3 vaccination resulted in a significant reduction of arginase-1(Arg-1)-induced nitric oxide synthase (iNOS), reactive oxygen species (ROS) and suppressed MDSC activity. Moreover, this concurrent depletion restored production of inflammatory cytokine IFN-γ and enhanced tumor-specific CTL response, which subsequently resulted in the reduction of tumor growth and the improved survival rate of vaccinated mice. In conclusion, our results revealed that Foxp3 vaccine promotes an immune response against tumor by targeting both Treg and MDSC, which could be exploited as a potential immunotherapy approach.


Assuntos
Vacinas Anticâncer/imunologia , Fatores de Transcrição Forkhead/metabolismo , Melanoma Experimental/imunologia , Células Supressoras Mieloides/imunologia , Linfócitos T Reguladores/imunologia , Vacinas de DNA/imunologia , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Ativação Linfocitária/imunologia , Melanoma Experimental/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células Supressoras Mieloides/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Linfócitos T Reguladores/metabolismo , Microambiente Tumoral/imunologia
7.
Neuroimmunomodulation ; 25(2): 80-88, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30071533

RESUMO

OBJECTIVES: Myasthenia gravis (MG) is an autoimmune disease accompanied by a thymic pathology and in most patients thymectomy (TE) is used as the therapeutic approach. Both B and T cells play an important role in MG pathogenesis. METHODS: Twelve pre- and post-TE MG patients and 12 healthy controls (HCs) were enrolled. The mean percentages of Th22 and Tc22 cells were evaluated in MG patients (before and 6 months after TE) and HCs. RESULTS: The mean percentage of Tc22 cells in pre-TE patients was significantly higher than in HCs (p < 0.05), and after TE Tc22 cells significantly decreased compared to pre-TE (p < 0.05). The frequency of Th22 cells in pre-TE MG patients was not significantly different from HCs, but after TE Th22 cells were significantly decreased compared to pre-TE (p < 0.05). CONCLUSION: Our findings suggest a possible role of Th22 and Tc22 in MG pathogenesis.


Assuntos
Miastenia Gravis/sangue , Miastenia Gravis/cirurgia , Linfócitos T Auxiliares-Indutores/metabolismo , Timectomia/tendências , Adulto , Contagem de Células/tendências , Feminino , Humanos , Masculino , Miastenia Gravis/diagnóstico , Subpopulações de Linfócitos T/metabolismo
8.
Clin Immunol ; 175: 124-132, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27664934

RESUMO

Common variable immunodeficiency (CVID) is a heterogeneous group of primary immunodeficiency characterized by recurrent infections. We evaluated whether defective PI3K/Akt/FoxO pathway could influence B-cell fate. Determination of B-cell subsets in CVD patients and healthy donors (HDs) were performed using flow cytometry. We evaluated mRNA and protein expression of PI3K, Akt and FoxO using real-time PCR and flow cytometry, respectively. Moreover, phosphorylated Akt (pAkt) expression in B-cells has been measured by flowcytometry. We identified a significant reduction in the percentage of marginal zone like B-cells, memory B-cells (total, switched and unswitched) and plasmablasts in patients, as these decreased B-cell subsets had a significant negative correlation with increased apoptosis in patients. Surprisingly, we identified decreased pAkt expression in B-cells of patients than HDs. We described for the first time impaired pAkt expression in B-cells of CVID patients that had a significant correlation with antibody response to the vaccine and worse clinical complications.


Assuntos
Subpopulações de Linfócitos B/metabolismo , Linfócitos B/imunologia , Linfócitos B/metabolismo , Imunodeficiência de Variável Comum/imunologia , Imunodeficiência de Variável Comum/metabolismo , Fosforilação/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Adolescente , Adulto , Subpopulações de Linfócitos B/imunologia , Criança , Feminino , Citometria de Fluxo/métodos , Humanos , Memória Imunológica/imunologia , Masculino , Fosfatidilinositol 3-Quinases/metabolismo , Adulto Jovem
9.
Neuroimmunomodulation ; 24(4-5): 264-270, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29414833

RESUMO

OBJECTIVE: Myasthenia gravis (MG) is an autoimmune disease mediated by autoantibodies against the neuromuscular junction. The thymus has an important role in the pathogenesis of MG because most patients have thymic pathology, and thymectomy (TE) can reduce the severity of the disease. METHODS: In this study, the frequency of Th17 and Tc17 cells was studied in 12 MG patients (pre-TE and 6 months post-TE) and in 12 healthy controls (HC). RESULTS: The frequency of Tc17 cells in the pre-TE patients was significantly higher than in the HC (p < 0.05), and after TE, these cells had significantly decreased compared to before TE (p < 0.05). The frequency of Th17 cells in pre-TE patients was significantly higher than in the HC (p < 0.05), and after TE, these cells had significantly decreased compared to before TE (p < 0.05). CONCLUSION: Our findings indicated a possible role of Tc17 and Th17 in MG pathogenesis.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Progressão da Doença , Miastenia Gravis/sangue , Células Th17/metabolismo , Timectomia , Adulto , Autoanticorpos/sangue , Feminino , Seguimentos , Humanos , Masculino , Miastenia Gravis/diagnóstico , Timectomia/tendências
10.
Psychosomatics ; 57(4): 359-68, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27129358

RESUMO

BACKGROUND: Among cardiac patients, positive psychologic factors are consistently linked with superior clinical outcomes and improvement in key markers of inflammation and hypothalamic-pituitary-adrenal axis functioning. Further, positive psychology interventions (PPI) have effectively increased psychologic well-being in a wide variety of populations. However, there has been minimal study of PPIs in cardiac patients, and no prior study has evaluated their effect on key prognostic biomarkers of cardiac outcome. Accordingly, we investigated the effect of 3 distinct PPIs on risk biomarkers in cardiac patients. METHODS: In an exploratory trial, 69 patients with recent coronary artery bypass graft surgery or percutaneous intervention were randomized to (1) one of three 6-week in-person PPIs (based on the work of Seligman, Lyubomirsky, or Fordyce) or (2) a wait-list control group. Risk biomarkers were assessed at baseline, postintervention (7 weeks), and at 15-week follow-up. Between-group differences in change from baseline biomarker levels were examined via random effects models. RESULTS: Compared with the control group, participants randomized to the Seligman (B = -2.06; p = 0.02) and Fordyce PPI (B = -1.54; p = 0.04) had significantly lower high-sensitivity C-reactive protein levels at 7 weeks. Further, the Lyubomirsky PPI (B = -245.86; p = 0.04) was associated with a significantly lower cortisol awakening response at 7 weeks when compared with control participants. There were no other significant between-group differences. CONCLUSION: Despite being an exploratory pilot study with multiple between-group comparisons, this initial trial offers the first suggestion that PPIs might be effective in reducing risk biomarkers in high-risk cardiac patients.


Assuntos
Proteína C-Reativa/metabolismo , Doença da Artéria Coronariana/psicologia , Depressão/psicologia , Hidrocortisona/metabolismo , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Idoso , Biomarcadores/metabolismo , Ponte de Artéria Coronária , Doença da Artéria Coronariana/metabolismo , Doença da Artéria Coronariana/cirurgia , Feminino , Humanos , Sistema Hipotálamo-Hipofisário , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea , Projetos Piloto , Sistema Hipófise-Suprarrenal , Risco , Saliva/química , Listas de Espera
11.
J Res Med Sci ; 21: 64, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27904609

RESUMO

BACKGROUND: It is supposed that human colorectal cancer consists of a phenotypically distinct population of tumorigenic cancer cells known as cancer stem cells (CSCs) which play a pivotal role in cancer progression, maintenance, metastasis, and the relapse. The aim of this effort was to investigate and compare biological characterizations of CD133+ with CD133- cell subsets isolated from both primary and metastatic human colorectal tumors. MATERIALS AND METHODS: Using our optimized protocols, unfixed colorectal tumors were enzymatically and mechanically dissociated into single cells followed by evaluation of postdigestion viability. The obtained single cell suspensions were then subjected to cell sorting using magnetic beads according to CD133 marker. The resultant CD133+ and CD133- cell subsets were cultured in specific cell culture medium followed by aldehyde dehydrogenases (ALDH) activity assessment and flow cytometric analyses. RESULTS: The results demonstrate that CD133+ cells have smaller size and lower complexity of intracellular structure, sphere formation ability, and ALDH enzyme activity while CD133- cells isolated from primary colon cancer samples were not able to form a sphere and did not show ALDH enzyme activity. Intriguingly, CD133- cells isolated from metastatic colorectal cancer specimen were able to form a sphere and shown ALDH enzyme activity. The present study indicates that our results are in agreement with SC theory and possibility of the existence of cellular plasticity among cancer subpopulations should be portrayed. CONCLUSION: We also conclude that this cellular plasticity is greatly affected by tumor microenvironment cues and the role of CSCs niche in cancer therapeutic strategies should be precisely considered.

12.
Int Arch Allergy Immunol ; 168(2): 122-30, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26678791

RESUMO

BACKGROUND: Low, noncytotoxic concentrations of various chemotherapeutic drugs like 5-fluorouracil (5-FU) induce antitumor immune responses by selectively depleting tumor-induced immunosuppressive cells, and could therefore be used in combination with dendritic cell (DC) vaccines in order to enhance their immunotherapeutic efficacy. However, the likely negative influences of low, noncytotoxic doses of 5-FU on bone marrow-derived (BM)-DCs in vitro have not yet been investigated. METHODS: The effects of low, noncytotoxic concentrations of 5-FU on mouse BM-DC differentiation and maturation markers (CD11c, MHC class II and CD80) as well as antigen-presenting capacity and cytokine production (IL-12p70 and IL-10) have been assessed. RESULTS: Different low doses of 5-FU had no significant effect on the expression of DC differentiation and maturation or on costimulatory markers (p = 0.5). Furthermore, suboptimal doses of 5-FU did not affect the immunostimulatory functions of DCs such as antigen presentation (p = 0.6) and cytokine production (p = 0.9). CONCLUSIONS: These data suggest that low doses of 5-FU have no adverse effects on DC maturation and function, and the efficacy of DC-based cancer immunotherapy may be greatly enhanced by combining it with suboptimal doses of 5-FU.


Assuntos
Adjuvantes Imunológicos/farmacologia , Antimetabólitos Antineoplásicos/farmacologia , Células Dendríticas/efeitos dos fármacos , Fluoruracila/farmacologia , Animais , Células da Medula Óssea/citologia , Vacinas Anticâncer , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Células Dendríticas/citologia , Células Dendríticas/imunologia , Feminino , Interleucina-10/imunologia , Interleucina-12/imunologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Neoplasias/terapia
13.
J Res Med Sci ; 19(Suppl 1): S22-5, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25002889

RESUMO

BACKGROUND: Some evidence has shown a relationship between human cytomegalovirus (CMV) infection and pregnancy loss. However, whether recurrent or latent CMV infection or altered immune response to CMV is related to recurrent pregnancy loss (RPL) is unclear. We evaluated CMV infection and avidity of antibodies to CMV in women with RPL. MATERIALS AND METHODS: This case-control study was conducted on 43 women with RPL referred to a clinical immunology out-patient clinic in Isfahan (Iran), and 43 age-matched multiparous women without history of abortion as control subjects. Patients and controls were evaluated for anti-CMV IgG and IgM antibodies and IgG avidity index (AI) using the enzyme linked immunosorbent assay method. Student's t-test and Chi-square test were used to analyze the data. RESULTS: One case (2.3%) of positive anti-CMV IgM was detected in each group. Anti-CMV IgG positivity was more frequent in patients than in controls (90.6% vs. 69.8%, P = 0.014), but there was no difference between the two groups in anti-CMV IgG AI (79.4 ± 11.4 vs. 80.1 ± 10.2, P = 0.781). IgG titer was significantly higher in seropositive cases with RPL than seropositive controls (5.18 ± 1.99 vs. 2.00 ± 0.81, P < 0.001). CONCLUSION: We found that previous exposure to CMV was significantly higher in patients with RPL than the control group. However, no association was found between IgG AI and RPL. Further investigations are needed to find whether latent CMV infection starts an indirect process of autoimmune etiology in RPL or women with RPL have recurrent or reactivation of CMV infection.

14.
J Res Med Sci ; 19(12): 1129-33, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25709652

RESUMO

BACKGROUND: Colorectal cancer is one of the most important causes of morbidity and mortality in the world. It has been suggested that tissue inhibitor of metalloproteinase-1 (TIMP-1) plays a particular role in cancer promotion. The objective of the present study was to compare the effect of repeated measurement of carcinoembryonic antigen (CEA) and TIMP-1 plasma levels in a follow-up response to chemotherapy treatment in patients with unresectable metastatic colorectal cancer by surgery. MATERIALS AND METHODS: All consecutive patients between 18 and 75 years old in both genders with rectal adenocarcinoma who referred to Sayed Al-Shohada Medical Center, during 6 months of study period enrolled in the study. Level of CEA and TIMP-1 were assessed before and after two cycles of chemotherapy. Furthermore, patients underwent computed tomography scan to assess response to chemotherapy. The sensitivity, specificity, and areas under the receiver operating characteristic curves (AUC) calculated for baseline level of CEA and TIMP. RESULTS: The mean age of the studied patients was 52.7 ± 7.5 years, 12 patients (48%) were male. Response to chemotherapy after two cycles was 80%. In patients who responded to chemotherapy level of TIMP after treatment was significantly decreased compared to before treatment (P < 0.0001). Before and after treatment in patients who responded to chemotherapy the level of TIMP was significantly lower than who did not response to chemotherapy (P < 0.05). The critical values for the prediction response to chemotherapy for CEA was >63 (AUC: 0.54) and for TIMP was ≤8823 (AUC: 0.68). CONCLUSION: The present study has identified a strong significant association between high plasma TIMP-1 levels and short survival in patients with colorectal cancer. In addition, results demonstrated that the TIMP-1 provides stronger prognostic information than CEA.

15.
PLoS One ; 19(4): e0301980, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38669276

RESUMO

This research introduces a new designing process and analysis of an innovative Silicon-on-Insulator Metal-Semiconductor Field-Effect (SOI MESFET) structure that demonstrates improved DC and RF characteristics. The design incorporates several modifications to control and reduce the electric field concentration within the channel. These modifications include relocating the transistor channel to sub-regions near the source and drain, adjusting the position of the gate electrode closer to the source, introducing an aluminum layer beneath the channel, and integrating an oxide layer adjacent to the gate. The results show that the AlOx-MESFET configuration exhibits a remarkable increase of 128% in breakdown voltage and 156% in peak power. Furthermore, due to enhanced conductivity and a significant reduction in gate-drain capacitance, there is a notable improvement of 53% in the cut-off frequency and a 28% increase in the maximum oscillation frequency. Additionally, the current gain experiences a boost of 15%. The improved breakdown voltage and peak power make it suitable for applications requiring robust performance under high voltage and power conditions. The increased maximum oscillation frequency and cut-off frequency make it ideal for high-frequency applications where fast signal processing is crucial. Moreover, the enhanced current gain ensures efficient amplification of signals. The introduced SOI MESFET structure with its modifications offers significant improvements in various performance metrics. It provides high oscillation frequency, better breakdown voltage and good cut-off frequency, and current gain compared to the traditional designs. These enhancements make it a highly desirable choice for applications that demand high-frequency and high-power capabilities.


Assuntos
Desenho de Equipamento , Silício , Silício/química , Semicondutores , Transistores Eletrônicos , Condutividade Elétrica , Fontes de Energia Elétrica , Metais/química
16.
PLoS One ; 19(5): e0302634, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38718001

RESUMO

In this paper, a new microstrip triplexer is designed to work at 2.5 GHz, 4.4 GHz and 6 GHz for mid-band 5G applications. All channels are flat with three low group delays (GDs) of 0.84 ns, 0.75 ns and 0.49 ns, respectively. Compared to the previously reported works, the proposed triplexer has the minimum group delay. The designed triplexer has 18.2%, 13.7%, 23.6% fractional bandwidths (FBW%) at 2.5 GHz, 4.4 GHz and 6 GHz, respectively. The obtained insertion losses (ILs) are low at all channels. These features are obtained without a noticeable increase in the overall size. A novel and simple resonator is used to design the proposed triplexer, which includes two pairs of coupled lines combined with a shunt stub. A perfect mathematical analysis is performed to find the resonator behavior and the layout optimization. The type of shunt stub is determined mathematically. Also, the smallness or largeness of some important physical dimensions is determined using the proposed mathematical analysis. Finally, the designed triplexer is fabricated and measured, where the measurement results verify the simulations.


Assuntos
Desenho de Equipamento , Tecnologia sem Fio , Tecnologia sem Fio/instrumentação
17.
Biotechnol Lett ; 35(8): 1191-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23553521

RESUMO

Hepcidin is a peptide hormone that plays an important role in iron metabolism. We have produced a recombinant mouse hepcidin-1 by using baculovirus expression system. Its expression yield was 25 µg/ml when cell culture media were supplemented with a protease inhibitor cocktail. The recombinant mouse hepcidin-1 and synthetic human hepcidin-25 had similar effects on reducing ferroportin expression in J774A cell line and in peritoneal macrophages. However, synthetic human hepcidin-25 was more efficient than recombinant mouse hepcidin-1 in reducing iron concentration in blood circulation (p < 0.01).


Assuntos
Proteínas de Transporte de Cátions/biossíntese , Hepcidinas/metabolismo , Ferro/metabolismo , Animais , Linhagem Celular , Hepcidinas/genética , Ferro/sangue , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Modelos Animais , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia
18.
Stem Cell Rev Rep ; 19(2): 368-381, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36331801

RESUMO

The induction of feto-maternal tolerance, fetal non-immunogenicity, and the regulation of mother's immune system are essential variables in a successful pregnancy. Fetal membranes have been used as a source of stem cells and biological components in recent decades. Human amniotic epithelial cells (hAEC) have stem/progenitor characteristics like those found in the amniotic membrane. Based on their immunomodulatory capabilities, recent studies have focused on the experimental and therapeutic applications of hAECs in allograft transplantation, autoimmune disorders, and gynecological problems such as recurrent spontaneous abortion (RSA), recurrent implantation failure (RIF), and premature ovarian failure (POF). This review discusses some of the immunomodulatory features and therapeutic potential of hAECs in preventing infertility, miscarriage, and implantation failure by controlling the maternal immune system.


Assuntos
Aborto Espontâneo , Infertilidade , Insuficiência Ovariana Primária , Gravidez , Feminino , Humanos , Aborto Espontâneo/terapia , Células Epiteliais , Insuficiência Ovariana Primária/terapia
19.
J Hum Reprod Sci ; 16(3): 246-256, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38045499

RESUMO

Background: Natural killer T (NKT) cells are influential immune cells in pregnancy failures, including recurrent spontaneous abortion (RSA). Different approaches are used for these disorders due to their effects on maternal immunomodulation. Aims: In the present study, we compared the effects of two typical immunotherapies (lymphocyte immunotherapy [LIT] and low-dose prednisolone) on CD3+CD56+CD16+ and CD3+CD56+CD8+ cells as two distinct subsets of NKT cells in Women with RSA. Settings and Design: This study was a comparative cohort study conducted from 2021 to 2022. One hundred and five women with RSA were distributed into three treatment groups randomly. Materials and Methods: Fifty women in the group of low-dose prednisolone therapy, fifty women in the LIT group and five women without any treatment as the control group were included in the study. NK and NKT cell subsets were assessed using flow cytometry. Furthermore, the concentration of interferon-gamma (IFN-γ), transforming growth factor-beta (TGF-ß) and interleukin-10 (IL-10) was measured quantitatively using the enzyme-linked immunosorbent assay technique. Statistical Analysis Used: Normality and comparisons between study groups were performed by non-parametric unpaired Mann-Whitney, Kruskal-Wallis rank sum test, and one-way ANOVA. Results: The percentage of CD56dim NK cells was increased after prednisolone therapy, while this population significantly decreased in the LIT group. In contrast to the LIT group, the administration of prednisolone increased CD3+CD8+CD56+ NKT cells (P < 0.0001), which is helpful for pregnancy. The effect of the investigated treatment approaches on the population of peripheral CD3+CD56+CD16+ NKT cells of women with RSA was not adequately significant. The same situation was also observed regarding the serum level of IFN-γ. However, a significant decrease in serum levels of IL-10 and TGF-ß was observed after prednisolone therapy. Conclusion: The lower capability of LIT in changing the population of NKT cells compared to prednisolone therapy may be due to its mechanism of action, which is related to the production of blocking antibodies. These treatment approaches had different effects on NKT cells, indicating that NKT cell population and function can be affected using LIT and prednisolone therapy distinctly. In addition, prednisolone therapy and LIT in women with normal serum levels of IFN-γ have no harmful effects in changing the production of this critical cytokine.

20.
PLoS One ; 18(12): e0296272, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38134045

RESUMO

Microstrip couplers play a crucial role in signal processing and transmission in various applications, including RF and wireless communication, radar systems, and satellites. In this work, a novel microstrip 180° coupler is designed, fabricated and measured. The layout configuration of this coupler is completely new and different from the previously reported Rat-race, branch-line and directional couplers. To obtain the proposed coupler, the meandrous coupled lines are used and analyzed mathematically. To improve the performance of our coupler, an optimization method is used. The designed coupler is very compact with an overall size of 0.014λg2. The obtained values of S21 and S31 are -3.45 dB and -3.75 dB, respectively at the operating frequency, while the fractional bandwidth (FBW) is 56.2%. It operates at fo = 1.61 GHz (suitable for 5G applications) and can suppress harmonics up to 2.17fo. Another advantage of this coupler is its low phase imbalance, while the phase difference between S21 and S31 is 180°± 0.023°. Therefore, our device is a balanced coupler with ±0.3 dB magnitude unbalance at its operating frequency. It is important to note that it is very difficult to find a coupler that has all these advantages at the same time. The proposed 180° coupler is fabricated and measured. The comparison shows that the measurement and simulation results are in good agreement. Therefore, the proposed coupler can be easily used in designing high-performance 5G communication systems.


Assuntos
Comunicação , Radar , Animais , Ratos , Simulação por Computador , Processamento de Sinais Assistido por Computador
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