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1.
Obes Surg ; 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38879726

ABSTRACT

Endoscopic bariatric therapies can provide treatment options for obesity in non-surgical candidates, as a part of combination or serial treatment plans, and for the reduction of obesity-related comorbidities. Several complications of intragastric balloons have been documented, but spontaneous hyperinflation is a risk that has not been well reported previously. We describe two cases of spontaneous intragastric balloon hyperinflation and their outcomes.

2.
Curr Pharm Des ; 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38676476

ABSTRACT

BACKGROUND: Breast Cancer (BC) is a serious malignancy among women. However, chemotherapy is an important tool for cancer treatments, but the long-term use of chemotherapy drugs may lead to drug resistance and tumor recurrence. Since Breast Cancer Stem Cells (BCSCs) can be the main factor to induce BC treatment resistance and recurrence, investigation of BCSCs signaling pathways can be an effective modality to enhance cancer treatment efficiency. OBJECTIVE: In this study, the effect of metformin, SB203580, and takinib alone or in combination with radiotherapy on MCF-7 and MDA-MB-231 breast cancer cell lines was evaluated. METHODS: MCF-7 and MDA-MB-231 breast cancer cell lines were treated with metformin, SB203580, and takinib for 24 or 48 hours, followed by X-ray exposure. The MTT assay and flow cytometry analysis were performed to assess cell growth inhibition and cellular death, CXCr4 expression, and BCSCs, respectively. RESULTS: The results showed the combination of takinib/SB203580 with radiotherapy to remarkably reduce the CXCR4 expression and BCSCs levels in the MCF-7 cell line. Also, the concurrent administration of takinib/metformin/radiotherapy significantly reduced BCSCs and CXCR4 metastatic markers in the MDA-MB- 231 cells. Since the MAPK signaling pathway has an important role in inducing drug resistance and cell proliferation, the use of SB203580 as an inhibitor of p38 MAPK can improve breast cancer treatment. Furthermore, metformin and ionizing radiation by suppression of the mTOR signaling pathway can control AMPK activation and cellular proliferation. CONCLUSION: Anti-cancer and cytotoxic effects of metformin can be effective in this strategy. In conclusion, the combination of conventional chemotherapeutic drugs, including SB203580, metformin, and takinib with X-ray exposure can be a new approach to diminish the drug resistance of breast cancer.

3.
Heliyon ; 9(11): e21060, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37964831

ABSTRACT

Breast cancer (BC) is the most common malignancy, and the largest cause of cancer death among women. The interactions between tumor cells and tumor micro environmental factors have a major impact on tumor progression. One of the critical pro-inflammatory cytokines present in breast cancer tumor microenvironment is TNF-α. The aim of this study was to evaluate the long-term effect of TNF-α (1 week) along with p38 or TAK1 inhibitors as well as metformin on induction of cellular death, cancer stem cell and expression of metastatic marker CXCR4. MCF-7 and MDA-MB-231 cells were treated with TNF-α for one week and then were treated with combination of Takinib, SB203580 or Metformin; after all treatments were done, cell proliferation, cellular death, surface expression of CXCR4, CD44 and CD24 were determined. The results showed that treatment with TNF-α alone or in combination with Takinib, SB203580 and metformin elevated induction of cellular death in both cell lines compared to the control group. TNF-α also increased CXCR4 expression in MCF-7 cells, but it reduced its expression in the MDA-MB-231 cells. Also, breast cancer stem cells (BCSCs) population decreased in MDA-MB-231 cells treated with TNF-α alone or in combination with SB203580 and metformin. Although, in MCF-7 cells only combination of TNF-α and Takinib reduced BCSCs population in a time dependent manner. Altogether, we showed that TNF-α alone or in combination with other treatments can affect the progression of breast cancer.

4.
Mol Biol Rep ; 50(10): 8319-8328, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37589934

ABSTRACT

BACKGROUND: Bromodomain and extra-terminal (BET) proteins are recognized acetylated lysine of histone 4 and act as scaffolds to recruit many other proteins to promoters and enhancers of active genes, especially at the super-enhancers of key genes, driving the transcription process and have been identified as potential therapeutic targets in breast cancer. However, the efficacy of BET inhibitors such as JQ1 in breast cancer therapy is impeded by interleukin-6 (IL-6) through an as-yet-defined mechanism. METHODS AND RESULTS: We investigated the interplay between IL-6 and JQ1 in MCF-7 and MDA-MB-231 human breast cancer cells. The results demonstrate that the efficacy of JQ1 on the inhibition of cell growth and apoptosis was stronger in MDA-MB-231 cells than in MCF-7 cells. Further, MCF-7 cells, but not MDA-MB-231 cells, exhibited increased expression of CXCR4 following IL-6 treatment. JQ1 significantly reduced CXCR4 surface expression in both cell lines and diminished the effects of IL-6 pre-treatment on MCF-7 cells. While IL-6 suppressed the extension of breast cancer stem cells in MCF-7 cells, JQ1 impeded its inhibitory effect. In MCF-7 cells JQ1 increased the number of senescent cells in a time-dependent manner. CONCLUSION: Analysis of gene expression indicated that JQ1 and IL-6 synergistically increase SNAIL expression and decrease c-MYC expression in MCF-7 cells. So, the BET proteins are promising, novel therapeutic targets in late-stage breast cancers. BET inhibitors similar to JQ1 show promise as therapeutic candidates for breast cancers, especially when triple-negative breast cancer cells are increased and/or tumor-promoting factors like IL-6 exist in the tumor microenvironment.


Subject(s)
Breast Neoplasms , Interleukin-6 , Female , Humans , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Cell Line, Tumor , Cell Proliferation , Interleukin-6/genetics , Interleukin-6/pharmacology , MCF-7 Cells , Proto-Oncogene Proteins c-myc/genetics , Proto-Oncogene Proteins c-myc/metabolism , Signal Transduction , Tumor Microenvironment
5.
Curr Pharm Des ; 29(14): 1092-1104, 2023.
Article in English | MEDLINE | ID: mdl-37070446

ABSTRACT

Numerous natural compounds have been identified that are able to induce apoptosis in cancer cells. These compounds have various chemical properties and are found in medicinal plants, vegetables, and fruits that are commonly consumed by humans. Phenols represent important compounds, which have been demonstrated to induce apoptosis in cancer cells, and some of the involved mechanisms have also been determined. The most important and abundant phenolic compounds are tannins, caffeic acid, capsaicin, gallic acid, resveratrol, and curcumin. Induction of apoptosis with the least or no toxicity to natural tissues is one of the useful effects of many plant-based bioactive compounds. Phenols, with anticancer potency at different degrees, serve to induce apoptosis through different pathways, including both extrinsic (Fas) and intrinsic (calcium release, ROS increase, DNA degradation, and mitochondrial membrane impairment). In this review, we report these compounds and their apoptosis-inducing mechanisms. Apoptosis or programmed cell death is a precise and systematic mechanism that is aimed at removing damaged or abnormal cells and is very useful to control, treat, and prevent cancer. Apoptotic cells are characterized by specific morphological features and molecular expression. In addition to physiological stimuli, there are many external factors that can be useful for inducing apoptosis. Also, these compounds can affect the regulatory proteins of the apoptotic pathways, such as the apoptotic proteins (Bid and BAX) and antiapoptotic proteins (Bcl-2). Taking these compounds and their molecular mechanisms into account can help use them in combination with chemical drugs and develop new drugs.


Subject(s)
Apoptosis , Leukemia , Humans , Cell Line , Apoptosis Regulatory Proteins/metabolism , Apoptosis Regulatory Proteins/pharmacology , Gallic Acid/pharmacology
6.
J Clin Gastroenterol ; 57(9): 951-955, 2023 10 01.
Article in English | MEDLINE | ID: mdl-36730665

ABSTRACT

BACKGROUND: Hospital admissions for patients with cirrhosis continue to increase. In New York City, 25% to 30% of hospitalized cirrhotics are readmitted within 30 days. Rehospitalization is associated with increased mortality, poor quality of life, and financial burden to patients, hospitals, and payers. Preventable readmissions are partially accounted for by a well-documented quality gap between evidence-based guidelines for cirrhosis management and real-world adherence to these recommendations. METHODS: We performed a prospective cohort study that compared outcomes among cirrhotic patients admitted to 4 internal medicine teams over a 6-month period. An electronic medical record (EMR) note template that outlined best-practice measures for cirrhotics was developed. Inpatient providers on 2 teams were instructed to include it in daily progress notes and discharge summaries. The recommended practices included diagnostic paracentesis and diuretics for ascites, rifaximin, and lactulose for hepatic encephalopathy, beta blockers for esophageal varices, and antibiotic prophylaxis for spontaneous bacterial peritonitis. The remaining 2 teams continued the standard of care for cirrhotic patients. The primary outcome was 30-day readmissions. Secondary outcomes included in-hospital mortality, 30-day mortality, length of stay, and adherence to best-practice guidelines. RESULTS: Over a 6-month period, 108 cirrhotic patients were admitted, 83 in the interventional group and 25 in the control group. MELD-Na scores on admission did not differ between the groups (20.1 vs. 21.1, P =0.56). Thirty-day readmissions were not significantly different between the interventional and control groups (19.3% vs. 24%, P =0.61). However, 30-day mortality was significantly lower in the interventional group (8.4% vs. 28%, P =0.01). There was no difference between the 2 groups in in-hospital mortality (4.8% vs. 0%, P =0.27), 90-day mortality (15.7% vs. 28.0%, P =0.17) or length of stay (10.2 vs. 12.6 d, P =0.34). Adherence to best-practice metrics was similar between the groups, except for rates of diagnostic paracentesis, which were higher in the interventional group (98% vs. 80%, P =0.01). CONCLUSION: Implementation of an EMR note template with cirrhosis best practices was associated with lower 30-day mortality and higher rates of diagnostic paracentesis among admitted patients with cirrhosis. These findings suggest that the integration of best-practice measures into the EMR may improve outcomes in hospitalized cirrhotic patients. Larger studies are required to validate these findings.


Subject(s)
Electronic Health Records , Quality of Life , Humans , Prospective Studies , Hospitalization , Liver Cirrhosis/diagnosis , Liver Cirrhosis/therapy , Liver Cirrhosis/complications
8.
J Cell Biochem ; 122(12): 1915-1924, 2021 12.
Article in English | MEDLINE | ID: mdl-34569079

ABSTRACT

Degeneration and apoptotic death of the photoreceptor cell-layer of retina are a major cause of irreversible blindness in the development era. The stem cell replacement therapy is one of the strategies for the retinal repairing. In addition, exogenous signals critically contribute to the direction of lineage decisions that causes the fate-restricted photoreceptor progenitors from stem cell progeny in culture. It has been found that epidermal growth factor (EGF), taurine, and retinoic acid (RA) initially act in the instructive as well as lineage-restricted way in the progenitor lineage for producing neuroretinal cells or photoreceptor like cells from stem cell. The study aims to investigate the effect of RA and taurine in differentiation of the human bone marrow stem cell into cone photoreceptors cells and retinal ganglion cells. Mesenchymal stem cell was derived from human bone marrow of the term delivery. Therefore, the cultured cells have been treated with Dulbecco's modified Eagle's medium (DMEM)/high glucose (H+ ). After the four-cell passage, basal medium was replaced with DMEM/F12 complemented with 50 µmol/L taurine, RA (1 µM) and EGF (1 µg/ml). Subsequently cellular change morphology was detected following 7 and 14 days. Then, gene expression of neuroretinal and photoreceptor cell biomarkers (CRX, OTX2, PKC-α, recoverin, and Rho) were examined by quantitative polymerase chain reaction (Q-PCR). Also, cells were cultured, fixed, and then immunocytochemical analyzed. Primary antibodies included CRX and Rho. Cellular morphology demonstrated spindle elongated morphology. Taurine alone and combination of RA upregulate neuroretinal and photoreceptor cell biomarkers in messenger RNA and protein levels but along with EGF have not significant effect. Our data showed that taurine combination with RA can differentiate bone marrow mesenchymal stem cells into neuroretinal or photoreceptor like cells in vitro that can offer an attractive treatment ground for transplantation in the cell-replacement therapy for some forms of the retinal degeneration.


Subject(s)
Bone Marrow Cells/metabolism , Cell Differentiation/drug effects , Mesenchymal Stem Cells/metabolism , Retinal Cone Photoreceptor Cells/metabolism , Retinal Ganglion Cells/metabolism , Tretinoin/pharmacology , Humans
9.
Adv Drug Deliv Rev ; 177: 113926, 2021 10.
Article in English | MEDLINE | ID: mdl-34403749

ABSTRACT

The delivery of macromolecules via the gastrointestinal (GI) tract remains a significant challenge. A variety of technologies using physical modes of drug delivery have been developed and investigated to overcome the epithelial cell layer of the GI tract for local and systemic delivery. These technologies include direct injection, jetting, ultrasound, and iontophoresis, which have been largely adapted from transdermal drug delivery. Direct injection of agents using needles through endoscopy has been used clinically for over a century. Jetting, a needle-less method of drug delivery where a high-speed stream of fluid medication penetrates tissue, has been evaluated pre-clinically for delivery of agents into the buccal mucosa. Ultrasound has been shown to be beneficial in enhancing delivery of macromolecules, including nucleic acids, in pre-clinical animal models. The application of an electric field gradient to drive drugs into tissues through the technique of iontophoresis has been shown to deliver highly toxic chemotherapies into GI tissues. Here in, we provide an in-depth overview of these physical modes of drug delivery in the GI tract and their clinical and preclinical uses.


Subject(s)
Drug Delivery Systems , Gastrointestinal Tract , Mucous Membrane , Animals , Humans , Iontophoresis , Ultrasonic Waves
10.
Article in English | MEDLINE | ID: mdl-34221071

ABSTRACT

Medicinal plants have long been studied due to their anticancer effects and use of them is commonly increased as a complementary and alternative medicine (CAM therapies) among patients with cancer. In this study, Alhagi maurorum (A.m) and Amygdalus haussknechtii (A.h) extracts were evaluated for their effects on inhibiting the growth of 4T1 breast cancer cells. Based on MTT assay results, the IC50s of A.m and A.h extracts were 57 µg/ml and 85 µg/ml, respectively. Then the cell migration, gene expression, and degree of apoptosis after 48 hours in each treated group with A.m and A.h extracts alone or in combination with docetaxel (DTX) on 4T1 cells were evaluated. A.m had a synergistic behavior with DTX (CI < 1). A.h reduced DTX IC50 but presented CI > 1. Cell migration assay showed that each extract alone or in combination with DTX prevented the migration of 4T1 cells. The Ao/EB staining and flowcytometry results confirmed that, in combination therapy, A.m + DTX and A.h + DTX induced apoptosis close to the level of DTX. Real-time PCR analysis showed that A.m + DTX (IC50 + IC25) downregulated the mRNA expression of HIF-1α and FZD7. A.m + DTX (IC50 + IC10) group decreased the expression of HIF-1α. Moreover, in A.h + DTX (IC50 + IC25) group, ß-Catenin and FZD7 were downregulated and upregulated, respectively. Generally, our findings suggest that the combination of A.m and DTX possesses synergistic antitumor effects on 4T1 cells, which may be a valuable choice for CAM therapies. A.h has an acceptable antitumor activity but not in combination with DTX.

11.
Proc Natl Acad Sci U S A ; 118(18)2021 05 04.
Article in English | MEDLINE | ID: mdl-33903257

ABSTRACT

The role of integrins, in particular αv integrins, in regulating insulin resistance is incompletely understood. We have previously shown that the αvß5 integrin ligand milk fat globule epidermal growth factor like 8 (MFGE8) regulates cellular uptake of fatty acids. In this work, we evaluated the impact of MFGE8 on glucose homeostasis. We show that acute blockade of the MFGE8/ß5 pathway enhances while acute augmentation dampens insulin-stimulated glucose uptake. Moreover, we find that insulin itself induces cell-surface enrichment of MFGE8 in skeletal muscle, which then promotes interaction between the αvß5 integrin and the insulin receptor leading to dampening of skeletal-muscle insulin receptor signaling. Blockade of the MFGE8/ß5 pathway also enhances hepatic insulin sensitivity. Our work identifies an autoregulatory mechanism by which insulin-stimulated signaling through its cognate receptor is terminated through up-regulation of MFGE8 and its consequent interaction with the αvß5 integrin, thereby establishing a pathway that can potentially be targeted to improve insulin sensitivity.


Subject(s)
Antigens, Surface/genetics , Insulin Resistance/genetics , Insulin/genetics , Milk Proteins/genetics , Receptors, Vitronectin/genetics , Animals , Antigens, CD/genetics , Fatty Acids/genetics , Fatty Acids/metabolism , Glucose/metabolism , Glycolipids/genetics , Glycoproteins/genetics , Homeostasis/genetics , Humans , Integrin alphaVbeta3/genetics , Lipid Droplets , Mice , Muscle, Skeletal/metabolism , Receptor, Insulin/genetics , Signal Transduction/genetics
12.
Polymers (Basel) ; 13(5)2021 Feb 28.
Article in English | MEDLINE | ID: mdl-33671101

ABSTRACT

This study examines the potential use of sodium alginate (SA) biopolymer as an environmentally sustainable agent for the stabilization of rubberized soil blends prepared using a high plasticity clay soil and tire-derived ground rubber (GR). The experimental program consisted of uniaxial compression and scanning electron microscopy (SEM) tests; the former was performed on three soil-GR blends (with GR-to-soil mass ratios of 0%, 5% and 10%) compacted (and cured for 1, 4, 7 and 14 d) employing distilled water and three SA solutions-prepared at SA-to-water (mass-to-volume) dosage ratios of 5, 10 and 15 g/L-as the compaction liquid. For any given GR content, the greater the SA dosage and/or the longer the curing duration, the higher the uniaxial compressive strength (UCS), with only minor added benefits beyond seven days of curing. This behaviour was attributed to the formation and propagation of so-called "cationic bridges" (developed as a result of a "Ca2+/Mg2+ ⟷ Na+ cation exchange/substitution" process among the clay and SA components) between adjacent clay surfaces over time, inducing flocculation of the clay particles. This clay amending mechanism was further verified by means of representative SEM images. Finally, the addition of (and content increase in) GR-which translates to partially replacing the soil clay content with GR particles and hence reducing the number of available attraction sites for the SA molecules to form additional cationic bridges-was found to moderately offset the efficiency of SA treatment.

13.
Am J Med Sci ; 361(1): 43-54, 2021 01.
Article in English | MEDLINE | ID: mdl-32928496

ABSTRACT

BACKGROUND: Helicobacter pylori (H. pylori) infection causes inflammation and increases the risk of developing peptic ulcer disease (PUD); however, the exact molecular mechanisms of PUD development remain unclear. The aim of this study was to investigate the expression of CCL18, CCL28, and CXCL13 in H. pylori-positive subjects in comparison with H. pylori-negative subjects, and to determine its association with different clinical outcomes and virulence factors. METHODS: In total, 55 H. pylori-positive subjects with gastritis, 47 H. pylori-positive subjects with PUD, and 48 H. pylori-negative subjects were enrolled in this study. CCL18, CCL28, and CXCL13 expression were determined using real time polymerase chain reaction (PCR). The virulence factors of H. pylori such as cytotoxin-associated gene A (cagA), outer inflammatory protein A (oipA), blood group antigen-binding adhesin (babA), and vacuolating cytotoxin A (VacA) genes were evaluated using PCR. RESULTS: CCL18, CCL28, and CXCL13 expression in H. pylori-positive subjects were significantly higher than H. pylori-negative subjects. CCL18 and CXCL13 expression in H. pylori-positive subjects with oipA+ and babA2+were significantly higher than H. pylori-positive subjects with oipA¯ and babA2¯. CCL18 and CXCL13 expression were found to be significantly elevated in H. pylori-positive subjects with gastritis compared with H. pylori-positive subjects with PUD. CCL28 expression was significantly higher in H. pylori-positive subjects with PUD compared with H. pylori-positive subjects with gastritis. CONCLUSIONS: The increased of CCL18 and CXCL13 may be involved in the pathogenesis of H. pylori-associated gastritis, while the increased of CCL28 may be involved in the pathogenesis of H. pylori-associated PUD.


Subject(s)
Chemokine CXCL13/genetics , Chemokines, CC/genetics , Gastritis/genetics , Helicobacter Infections/genetics , Peptic Ulcer/genetics , Adult , Aged , Chemokine CXCL13/metabolism , Chemokines, CC/metabolism , Female , Gastritis/epidemiology , Gastritis/microbiology , Helicobacter Infections/epidemiology , Helicobacter Infections/microbiology , Helicobacter pylori/physiology , Humans , Iran/epidemiology , Male , Middle Aged , Peptic Ulcer/epidemiology , Peptic Ulcer/microbiology , Up-Regulation
14.
VideoGIE ; 5(11): 510-512, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33204902
15.
Mol Biol Rep ; 47(9): 6941-6947, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32888128

ABSTRACT

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) with increasing incidence and prevalence in developed countries. The presence of inflammatory cytokines is considered the main detrimental factor in severe types of IBD. The Nrf2 transcription factor plays an important role in reducing the expression of inflammatory agents such as interleukin (IL)-1ß and increasing reparative factors such as IL-11. Resveratrol, a plant-derived phenolic compound, reduces the damage in chronic experimentally induced colitis. Twenty patients with UC and also 20 healthy controls were recruited in this study. The proteins expression of Nrf2 and IL-1ß was assessed in colonic biopsies by Western blotting. Caco-2 cells were challenged with TNF-α (in vitro simulation of UC), in the presence or not of 190 nM (24 h) and 75 nM (48 h) Resveratrol. Then, Nrf2 and IL-1ß in gene and protein expression were measured by real time-PCR and Western blotting in different treatments. Finally, IL-11 proteins expression was measured in culture supernatant by ELISA. A significant increase of IL-1ß protein was detected in inflamed colonic tissues from UC patients compared with the control individuals. In Caco-2 cells challenged with TNF-α, protein expression of IL-1ß and p-Nrf2 showed an increase, while gene expression of Nrf2 did not show a significant difference. After treatment with Resveratrol, both IL-1ß mRNA and protein levels were reduced, while IL-11 protein levels showed any increase. The p-Nrf2 is a dominant form which is prevalent in inflamed tissues from UC patients. Resveratrol can reverse the inflammatory effects of TNF-α by reducing IL-1ß and increasing IL-11 production.


Subject(s)
Colitis, Ulcerative/drug therapy , Colitis, Ulcerative/metabolism , Gene Expression Regulation/drug effects , Interleukin-1beta/metabolism , NF-E2-Related Factor 2/metabolism , Resveratrol/pharmacology , Tumor Necrosis Factor-alpha/pharmacology , Adult , Caco-2 Cells , Colitis, Ulcerative/genetics , Colitis, Ulcerative/prevention & control , Down-Regulation , Female , Gene Expression Regulation/genetics , Humans , Interleukin-11/metabolism , Interleukin-1beta/genetics , Male , NF-E2-Related Factor 2/genetics , Up-Regulation
16.
J Am Soc Cytopathol ; 9(5): 389-395, 2020.
Article in English | MEDLINE | ID: mdl-32680792

ABSTRACT

Endoscopic ultrasound-guided tissue acquisition is now an imperative technique for the diagnosis of multiple diseases in the gastrointestinal tract and nearby structures. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) and fine needle biopsy via dedicated FNB needles (EUS-FNB) are two standard-essential tools for tissue acquisition. The choice of needle type is an important factor determining appropriate tissue acquisition. Multiple studies have compared EUS-FNA versus EUS-FNB on different lesions also there are several studies evaluated different needles in terms of sampling adequacy and cytological and histological accuracy. Prior studies comparing prior-generation FNB needles to FNA did not show an increased diagnostic yield with FNB. However, the newer-generation needles have demonstrated enhanced performance compared with their predecessors. As they may provide a large amount of tissue for the cytological and histological evaluation, rapid onsite specimen evaluation (ROSE), and immunohistochemical and molecular analyses, which may be very important for targeted therapy. In this review, we discuss current evidence and literature on the use of the newer generation needles for pancreatic and non-pancreatic lesions.


Subject(s)
Autoimmune Pancreatitis/diagnostic imaging , Endoscopic Ultrasound-Guided Fine Needle Aspiration/instrumentation , Endoscopic Ultrasound-Guided Fine Needle Aspiration/methods , Gastrointestinal Neoplasms/diagnostic imaging , Lymphoma/diagnostic imaging , Needles/classification , Pancreatic Neoplasms/diagnostic imaging , Autoimmune Pancreatitis/pathology , Gastrointestinal Neoplasms/pathology , Gastrointestinal Tract/pathology , Humans , Lymph Nodes/diagnostic imaging , Lymph Nodes/pathology , Lymphoma/pathology , Pancreas/diagnostic imaging , Pancreas/pathology , Pancreatic Neoplasms/pathology
17.
Light Sci Appl ; 9: 97, 2020.
Article in English | MEDLINE | ID: mdl-32549977

ABSTRACT

Plasma waves play an important role in many solid-state phenomena and devices. They also become significant in electronic device structures as the operation frequencies of these devices increase. A prominent example is field-effect transistors (FETs), that witness increased attention for application as rectifying detectors and mixers of electromagnetic waves at gigahertz and terahertz frequencies, where they exhibit very good sensitivity even high above the cut-off frequency defined by the carrier transit time. Transport theory predicts that the coupling of radiation at THz frequencies into the channel of an antenna-coupled FET leads to the development of a gated plasma wave, collectively involving the charge carriers of both the two-dimensional electron gas and the gate electrode. In this paper, we present the first direct visualization of these waves. Employing graphene FETs containing a buried gate electrode, we utilize near-field THz nanoscopy at room temperature to directly probe the envelope function of the electric field amplitude on the exposed graphene sheet and the neighboring antenna regions. Mapping of the field distribution documents that wave injection is unidirectional from the source side since the oscillating electrical potentials on the gate and drain are equalized by capacitive shunting. The plasma waves, excited at 2 THz, are overdamped, and their decay time lies in the range of 25-70 fs. Despite this short decay time, the decay length is rather long, i.e., 0.3-0.5 µm, because of the rather large propagation speed of the plasma waves, which is found to lie in the range of 3.5-7 × 106 m/s, in good agreement with theory. The propagation speed depends only weakly on the gate voltage swing and is consistent with the theoretically predicted 1 4 power law.

18.
Article in English | MEDLINE | ID: mdl-32374285

ABSTRACT

Background Experiencing early-life stress plays an important role in the pathophysiology of anxiety disorders. Ferulic acid is a phenolic compound found in some plants which has several pharmacological properties. N-methyl-D-aspartate (NMDA) receptors are involved in the pathophysiology of mood disorders. In this study we aimed to assess the anxiolytic-like effect of ferulic acid in a mouse model of maternal separation (MS) stress by focusing on the possible involvement of NMDA receptors. Methods Mice were treated with ferulic acid (5 and 40 mg/kg) alone and in combination with NMDA receptor agonist/antagonist. Valid behavioral tests were performed, including open field test (OFT) and elevated plus maze test (EPM), while quantitative real time polymerase chain reaction (qRT-PCR) was used to evaluate gene expression of NMDA subunits (GluN2A and GluN2B) in the hippocampus. Results Findings showed that treatment of MS mice with ferulic acid increased the time spent in the central zone of the OFT and increased both open arm time and the percent of open arm entries in the EPM. Ferulic acid reduced the expression of NMDA receptor subunit genes. We showed that administration of NMDA receptor agonist (NMDA) and antagonist (ketamine) exerted anxiogenic and anxiolytic-like effects, correspondingly. Results showed that co-administration of a sub-effective dose of ferulic acid plus ketamine potentiated the anxiolytic-like effect of ferulic acid. Furthermore, co-administration of an effective dose of ferulic acid plus NMDA receptor agonist (NMDA) attenuated the anxiolytic-like effect of ferulic acid. Conclusions In deduction, our findings showed that NMDA, partially at least, is involved in the anxiolytic-like effect of ferulic acid in the OFT and EPM tests.

20.
Int J Neurosci ; 130(2): 107-116, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31599165

ABSTRACT

Background and objectives: With regard to their ease of harvest and common developmental origin, dental pulp stem cells (DPSCs) may act as a favorable source of stem cells in generation of nerves. Moreover; cellular migration and differentiation as well as survival, self-renewal, and proliferation of neuroprogenitor species require the presence of the central nervous system (CNS) mitogens including EGF and bFGF. Accordingly, the possibility of the induction of neuronal differentiation of DPSCs by EGF and bFGF was evaluated in the present study.Materials and methods: DPSCs were treated with 20 ng/ml EGF, 20 ng/ml bFGF, and 10 µg/ml heparin. In order to further induce the neuroprogenitor differentiation, DPSC-derived spheres were also incubated in serum-free media for three days. The resulting spheres were then cultured in high-glucose Dulbecco's Modified Eagle Medium (DMEM) with 10% FBS. The morphology of the cells and the expression of the differentiation markers were correspondingly analyzed by quantitative polymerase chain reaction (qPCR), western blotting, and immunofluorescence (IF).Results: The EGF/bFGF-treated DPSCs showed significant increase in the expression of the neuroprogenitor markers of Nestin and SRY (sex determining region Y)-box 2 (SOX2), 72 h after treatment. The up-regulation of Nestin and SOX2 induced by growth factors was confirmed using western blotting and IF. The cultures also yielded some neuron-like cells with a significant rise in Nestin, microtubule-associated protein 2 (MAP2), and Neurogenin 1 (Ngn1) transcript levels; compared with cells maintained in the control media (p < 0.05).Conclusion: DPSCs seemed to potentially differentiate into neuron-like cells under the herein-mentioned treatment conditions.


Subject(s)
Cell Differentiation/physiology , Dental Pulp/cytology , Nerve Regeneration/physiology , Neurons/physiology , Stem Cells/physiology , Cells, Cultured , Cytological Techniques , Humans , Spheroids, Cellular/physiology
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