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1.
Int J Mol Sci ; 25(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38396943

RESUMO

microRNAs (miRNAs) are key regulators of both physiological and pathophysiological mechanisms in diabetes and gastrointestinal (GI) dysmotility. Our previous studies have demonstrated the therapeutic potential of miR-10a-5p mimic and miR-10b-5p mimic (miR-10a/b mimics) in rescuing diabetes and GI dysmotility in murine models of diabetes. In this study, we elucidated the safety profile of a long-term treatment with miR-10a/b mimics in diabetic mice. Male C57BL/6 mice were fed a high-fat, high-sucrose diet (HFHSD) to induce diabetes and treated by five subcutaneous injections of miR-10a/b mimics for a 5 month period. We examined the long-term effects of the miRNA mimics on diabetes and GI dysmotility, including an assessment of potential risks for cancer and inflammation in the liver and colon using biomarkers. HFHSD-induced diabetic mice subcutaneously injected with miR-10a/b mimics on a monthly basis for 5 consecutive months exhibited a marked reduction in fasting blood glucose levels with restoration of insulin and significant weight loss, improved glucose and insulin intolerance, and restored GI transit time. In addition, the miR-10a/b mimic-treated diabetic mice showed no indication of risk for cancer development or inflammation induction in the liver, colon, and blood for 5 months post-injections. This longitudinal study demonstrates that miR-10a/b mimics, when subcutaneously administered in diabetic mice, effectively alleviate diabetes and GI dysmotility for 5 months with no discernible risk for cancer or inflammation in the liver and colon. The sustained efficacy and favorable safety profiles position miR-10a/b mimics as promising candidates in miRNA-based therapeutics for diabetes and GI dysmotility.


Assuntos
Diabetes Mellitus Experimental , MicroRNAs , Neoplasias , Masculino , Animais , Camundongos , Diabetes Mellitus Experimental/genética , Estudos Longitudinais , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Inflamação , Fígado , Insulina , Colo
2.
Luminescence ; 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38148293

RESUMO

The present study investigates the impact of the ligand environment on the luminescence and thermometric behavior of Sm3+ doped A3 (PO4 )2 (A = Sr, Ca) phosphors prepared by combustion synthesis. The structural and luminescent properties of Sm3+ ions in the phosphate lattices were investigated using powder X-ray diffraction (PXRD) and photoluminescence (PL) techniques. PXRD results of the synthesized phosphors exhibit the expected phases that are in agreement with their respective standards. Fourier-transform infrared (FTIR) spectroscopy confirms the presence of PO4 vibrational bands. Upon excitation with near ultraviolet light, the PL studies indicated that Sr3 (PO4 )2 :Sm3+ phosphors exhibit a yellow light emission, whereas Ca3 (PO4 )2 :Sm3+ phosphors exhibit an emission of orange light. The PL emission results are in accordance with the CIE coordinates, with the Sr3 (PO4 )2 :Sm3+ phosphors showing coordinates of (0.56, 0.44), and the Ca3 (PO4 )2 :Sm3+ phosphors displaying coordinates of (0.60, 0.40). Thermal analysis shows improved stability of Ca3 (PO4 )2 :Sm3+ based on lower weight reduction in thermogravimetric analysis. The effect of temperature on the luminescence properties of the phosphor has been examined upon a 405 nm excitation. By using the fluorescence intensity ratio (FIR) method, the temperature responses of the emission ratios from the Sm3+ : the 4 F3/2 → 6 H5/2 transition to the 4 G5/2 → 6 H7/2 and 4 F3/2 → 6 H5/2 transition to the 4 G5/2 → 6 H9/2 emissions are characterized. The Ca3 (PO4 )2 :Sm3+ phosphors are more sensitive as compared with the Sr3 (PO4 )2 :Sm3+ phosphors. The earlier research findings strongly indicate that these phosphors hold great promise as ideal candidates for applications in non-invasive optical thermometry and solid-state lighting devices.

3.
Molecules ; 28(16)2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37630410

RESUMO

Prostate-specific membrane antigen (PSMA)-based low-molecular-weight agents using beta(ß)-particle-emitting radiopharmaceuticals is a new treatment paradigm for patients with metastatic castration-resistant prostate cancer. Although results have been encouraging, there is a need to improve the tumor residence time of current PSMA-based radiotherapeutics. Albumin-binding moieties have been used strategically to enhance the tumor uptake and retention of existing PSMA-based investigational agents. Previously, we developed a series of PSMA-based, ß-particle-emitting, low-molecular-weight compounds. From this series, 177Lu-L1 was selected as the lead agent because of its reduced off-target radiotoxicity in preclinical studies. The ligand L1 contains a PSMA-targeting Lys-Glu urea moiety with an N-bromobenzyl substituent in the ε-amino group of Lys. Here, we structurally modified 177Lu-L1 to improve tumor targeting using two known albumin-binding moieties, 4-(p-iodophenyl) butyric acid moiety (IPBA) and ibuprofen (IBU), and evaluated the effects of linker length and composition. Six structurally related PSMA-targeting ligands (Alb-L1-Alb-L6) were synthesized based on the structure of 177Lu-L1. The ligands were assessed for in vitro binding affinity and were radiolabeled with 177Lu following standard protocols. All 177Lu-labeled analogs were studied in cell uptake and selected cell efficacy studies. In vivo pharmacokinetics were investigated by conducting tissue biodistribution studies for 177Lu-Alb-L2-177Lu-Alb-L6 (2 h, 24 h, 72 h, and 192 h) in male NSG mice bearing human PSMA+ PC3 PIP and PSMA- PC3 flu xenografts. Preliminary therapeutic ratios of the agents were estimated from the area under the curve (AUC0-192h) of the tumors, blood, and kidney uptake values. Compounds were obtained in >98% radiochemical yields and >99% purity. PSMA inhibition constants (Kis) of the ligands were in the ≤10 nM range. The long-linker-based agents, 177Lu-Alb-L4 and 177Lu-Alb-L5, displayed significantly higher tumor uptake and retention (p < 0.001) than the short-linker-bearing 177Lu-Alb-L2 and 177Lu-Alb-L3 and a long polyethylene glycol (PEG) linker-bearing agent, 177Lu-Alb-L6. The area under the curve (AUC0-192h) of the PSMA+ PC3 PIP tumor uptake of 177Lu-Alb-L4 and 177Lu-Alb-L5 were >4-fold higher than 177Lu-Alb-L2, 177Lu-Alb-L3, and 177Lu-Alb-L6, respectively. Also, the PSMA+ PIP tumor uptake (AUC0-192h) of 177Lu-Alb-L2 and 177Lu-Alb-L3 was ~1.5-fold higher than 177Lu-Alb-L6. However, the lowest blood AUC0-192h and kidney AUC0-192h were associated with 177Lu-Alb-L6 from the series. Consequently, 177Lu-Alb-L6 displayed the highest ratios of AUC(tumor)-to-AUC(blood) and AUC(tumor)-to-AUC(kidney) values from the series. Among the other agents, 177Lu-Alb-L4 demonstrated a nearly similar ratio of AUC(tumor)-to-AUC(blood) as 177Lu-Alb-L6. The tumor-to-blood ratio was the dose-limiting therapeutic ratio for all of the compounds. Conclusions: 177Lu-Alb-L4 and 177Lu-Alb-L6 showed high tumor uptake in PSMA+ tumors and tumor-to-blood ratios. The data suggest that linker length and composition can be modulated to generate an optimized therapeutic agent.


Assuntos
Albuminas , Partículas beta , Humanos , Masculino , Animais , Camundongos , Ligantes , Distribuição Tecidual , Ácido Butírico
4.
Gastroenterology ; 161(2): 608-622.e7, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33895170

RESUMO

BACKGROUND & AIMS: Constipation is commonly associated with diabetes. Serotonin (5-HT), produced predominantly by enterochromaffin (EC) cells via tryptophan hydroxylase 1 (TPH1), is a key modulator of gastrointestinal (GI) motility. However, the role of serotonergic signaling in constipation associated with diabetes is unknown. METHODS: We generated EC cell reporter Tph1-tdTom, EC cell-depleted Tph1-DTA, combined Tph1-tdTom-DTA, and interstitial cell of Cajal (ICC)-specific Kit-GCaMP6 mice. Male mice and surgically ovariectomized female mice were fed a high-fat high-sucrose diet to induce diabetes. The effect of serotonergic signaling on GI motility was studied by examining 5-HT receptor expression in the colon and in vivo GI transit, colonic migrating motor complexes (CMMCs), and calcium imaging in mice treated with either a 5-HT2B receptor (HTR2B) antagonist or agonist. RESULTS: Colonic transit was delayed in males with diabetes, although colonic Tph1+ cell density and 5-HT levels were increased. Colonic transit was not further reduced in diabetic mice by EC cell depletion. The HTR2B protein, predominantly expressed by colonic ICCs, was markedly decreased in the colonic muscles of males and ovariectomized females with diabetes. Ca2+ activity in colonic ICCs was decreased in diabetic males. Treatment with an HTR2B antagonist impaired CMMCs and colonic motility in healthy males, whereas treatment with an HTR2B agonist improved CMMCs and colonic motility in males with diabetes. Colonic transit in ovariectomized females with diabetes was also improved significantly by the HTR2B agonist treatment. CONCLUSIONS: Impaired colonic motility in mice with diabetes was improved by enhancing HTR2B signaling. The HTR2B agonist may provide therapeutic benefits for constipation associated with diabetes.


Assuntos
Colo/efeitos dos fármacos , Constipação Intestinal/prevenção & controle , Complicações do Diabetes/prevenção & controle , Motilidade Gastrointestinal/efeitos dos fármacos , Indóis/farmacologia , Células Intersticiais de Cajal/efeitos dos fármacos , Complexo Mioelétrico Migratório/efeitos dos fármacos , Receptor 5-HT2B de Serotonina/efeitos dos fármacos , Agonistas do Receptor 5-HT2 de Serotonina/farmacologia , Tiofenos/farmacologia , Animais , Sinalização do Cálcio , Colo/metabolismo , Colo/fisiopatologia , Constipação Intestinal/etiologia , Constipação Intestinal/metabolismo , Constipação Intestinal/fisiopatologia , Complicações do Diabetes/metabolismo , Complicações do Diabetes/fisiopatologia , Modelos Animais de Doenças , Feminino , Genes Reporter , Células Intersticiais de Cajal/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Ovariectomia , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Receptor 5-HT2B de Serotonina/metabolismo , Serotonina/metabolismo , Triptofano Hidroxilase/genética , Triptofano Hidroxilase/metabolismo
5.
Gastroenterology ; 160(5): 1662-1678.e18, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33421511

RESUMO

BACKGROUND & AIMS: Interstitial cells of Cajal (ICCs) and pancreatic ß cells require receptor tyrosine kinase (KIT) to develop and function properly. Degeneration of ICCs is linked to diabetic gastroparesis. The mechanisms linking diabetes and gastroparesis are unclear, but may involve microRNA (miRNA)-mediated post-transcriptional gene silencing in KIT+ cells. METHODS: We performed miRNA-sequencing analysis from isolated ICCs in diabetic mice and plasma from patients with idiopathic and diabetic gastroparesis. miR-10b-5p target genes were identified and validated in mouse and human cell lines. For loss-of-function studies, we used KIT+ cell-restricted mir-10b knockout mice and KIT+ cell depletion mice. For gain-of-function studies, a synthetic miR-10b-5p mimic was injected in multiple diabetic mouse models. We compared the efficacy of miR-10b-5p mimic treatment vs antidiabetic and prokinetic medicines. RESULTS: miR-10b-5p is highly expressed in ICCs from healthy mice, but drastically depleted in ICCs from diabetic mice. A conditional knockout of mir-10b in KIT+ cells or depletion of KIT+ cells in mice leads to degeneration of ß cells and ICCs, resulting in diabetes and gastroparesis. miR-10b-5p targets the transcription factor Krüppel-like factor 11 (KLF11), which negatively regulates KIT expression. The miR-10b-5p mimic or Klf11 small interfering RNAs injected into mir-10b knockout mice, diet-induced diabetic mice, and TALLYHO polygenic diabetic mice rescue the diabetes and gastroparesis phenotype for an extended period of time. Furthermore, the miR-10b-5p mimic is more effective in improving glucose homoeostasis and gastrointestinal motility compared with common antidiabetic and prokinetic medications. CONCLUSIONS: miR-10b-5p is a key regulator in diabetes and gastrointestinal dysmotility via the KLF11-KIT pathway. Restoration of miR-10b-5p may provide therapeutic benefits for these disorders.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus/prevenção & controle , Esvaziamento Gástrico , Trânsito Gastrointestinal , Gastroparesia/prevenção & controle , Células Secretoras de Insulina/metabolismo , Células Intersticiais de Cajal/metabolismo , MicroRNAs/metabolismo , Adulto , Idoso , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Diabetes Mellitus/genética , Diabetes Mellitus/metabolismo , Modelos Animais de Doenças , Feminino , Gastroparesia/genética , Gastroparesia/metabolismo , Gastroparesia/fisiopatologia , Células HEK293 , Humanos , Células Secretoras de Insulina/patologia , Células Intersticiais de Cajal/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/genética , Pessoa de Meia-Idade , Células NIH 3T3 , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Adulto Jovem
6.
Gastroenterology ; 160(7): 2451-2466.e19, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33662386

RESUMO

BACKGROUND & AIMS: Gastrointestinal (GI) motility is regulated by serotonin (5-hydroxytryptamine [5-HT]), which is primarily produced by enterochromaffin (EC) cells in the GI tract. However, the precise roles of EC cell-derived 5-HT in regulating gastric motility remain a major point of conjecture. Using a novel transgenic mouse line, we investigated the distribution of EC cells and the pathophysiologic roles of 5-HT deficiency in gastric motility in mice and humans. METHODS: We developed an inducible, EC cell-specific Tph1CreERT2/+ mouse, which was used to generate a reporter mouse line, Tph1-tdTom, and an EC cell-depleted line, Tph1-DTA. We examined EC cell distribution, morphology, and subpopulations in reporter mice. GI motility was measured in vivo and ex vivo in EC cell-depleted mice. Additionally, we evaluated 5-HT content in biopsy and plasma specimens from patients with idiopathic gastroparesis (IG). RESULTS: Tph1-tdTom mice showed EC cells that were heterogeneously distributed throughout the GI tract with the greatest abundance in the antrum and proximal colon. Two subpopulations of EC cells were identified in the gut: self-renewal cells located at the base of the crypt and mature cells observed in the villi. Tph1-DTA mice displayed delayed gastric emptying, total GI transit, and colonic transit. These gut motility alterations were reversed by exogenous provision of 5-HT. Patients with IG had a significant reduction of antral EC cell numbers and 5-HT content, which negatively correlated with gastric emptying rate. CONCLUSIONS: The Tph1CreERT2/+ mouse provides a powerful tool to study the functional roles of EC cells in the GI tract. Our findings suggest a new pathophysiologic mechanism of 5-HT deficiency in IG.


Assuntos
Esvaziamento Gástrico/genética , Trânsito Gastrointestinal/genética , Serotonina/deficiência , Animais , Linhagem Celular , Células Enterocromafins/fisiologia , Humanos , Camundongos , Camundongos Transgênicos , Triptofano Hidroxilase/metabolismo
7.
Int J Mol Sci ; 23(5)2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35269876

RESUMO

Following the discovery of nucleic acids by Friedrich Miescher in 1868, DNA and RNA were recognized as the genetic code containing the necessary information for proper cell functioning. In the years following these discoveries, vast knowledge of the seemingly endless roles of RNA have become better understood. Additionally, many new types of RNAs were discovered that seemed to have no coding properties (non-coding RNAs), such as microRNAs (miRNAs). The discovery of these new RNAs created a new avenue for treating various human diseases. However, RNA is relatively unstable and is degraded fairly rapidly once administered; this has led to the development of novel delivery mechanisms, such as nanoparticles to increase stability as well as to prevent off-target effects of these molecules. Current advances in RNA-based therapies have substantial promise in treating and preventing many human diseases and disorders through fixing the pathology instead of merely treating the symptomology similarly to traditional therapeutics. Although many RNA therapeutics have made it to clinical trials, only a few have been FDA approved thus far. Additionally, the results of clinical trials for RNA therapeutics have been ambivalent to date, with some studies demonstrating potent efficacy, whereas others have limited effectiveness and/or toxicity. Momentum is building in the clinic for RNA therapeutics; future clinical care of human diseases will likely comprise promising RNA therapeutics. This review focuses on the current advances of RNA therapeutics and addresses current challenges with their development.


Assuntos
MicroRNAs , Nanopartículas , Ácidos Nucleicos , Humanos , MicroRNAs/genética , Nanopartículas/uso terapêutico , RNA Interferente Pequeno/genética , RNA não Traduzido/genética
8.
Int J Mol Sci ; 23(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35563399

RESUMO

Metalloendopeptidase ADAM-Like Decysin 1 (ADAMDEC1) is an anti-inflammatory peptidase that is almost exclusively expressed in the gastrointestinal (GI) tract. We have recently found abundant and selective expression of Adamdec1 in colonic mucosal PDGFRα+ cells. However, the cellular origin for this gene expression is controversial as it is also known to be expressed in intestinal macrophages. We found that Adamdec1 mRNAs were selectively expressed in colonic mucosal subepithelial PDGFRα+ cells. ADAMDEC1 protein was mainly released from PDGFRα+ cells and accumulated in the mucosal layer lamina propria space near the epithelial basement membrane. PDGFRα+ cells significantly overexpressed Adamdec1 mRNAs and protein in DSS-induced colitis mice. Adamdec1 was predominantly expressed in CD45- PDGFRα+ cells in DSS-induced colitis mice, with only minimal expression in CD45+ CD64+ macrophages. Additionally, overexpression of both ADAMDEC1 mRNA and protein was consistently observed in PDGFRα+ cells, but not in CD64+ macrophages found in human colonic mucosal tissue affected by Crohn's disease. In summary, PDGFRα+ cells selectively express ADAMDEC1, which is localized to the colon mucosa layer. ADAMDEC1 expression significantly increases in DSS-induced colitis affected mice and Crohn's disease affected human tissue, suggesting that this gene can serve as a diagnostic and/or therapeutic target for intestinal inflammation and Crohn's disease.


Assuntos
Proteínas ADAM , Colite , Doença de Crohn , Doenças Inflamatórias Intestinais , Proteínas ADAM/genética , Proteínas ADAM/metabolismo , Animais , Biomarcadores , Colite/induzido quimicamente , Colite/genética , Colite/metabolismo , Colo/citologia , Colo/metabolismo , Doença de Crohn/metabolismo , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/metabolismo , Mucosa Intestinal/metabolismo , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo
9.
Nano Lett ; 20(6): 4659-4666, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32437616

RESUMO

High quality factor mechanical resonators have shown great promise in the development of classical and quantum technologies. Simultaneously, progress has been made in developing controlled mechanical nonlinearity. Here, we combine these two directions of progress in a single platform consisting of coupled silicon nitride (SiNx) and graphene mechanical resonators. We show that nonlinear response can be induced on a large area SiNx resonator mode and can be efficiently controlled by coupling it to a gate-tunable, freely suspended graphene mode. The induced nonlinear response of the hybrid modes, as measured on the SiNx resonator surface is giant, with one of the highest measured Duffing constants. We observe a novel phononic frequency comb which we use as an alternate validation of the measured values, along with numerical simulations which are in overall agreement with the measurements.

10.
Mediators Inflamm ; 2020: 5239419, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33414685

RESUMO

Breast cancer results from a complex interplay of genetics and environment that alters immune and inflammatory systems to promote tumorigenesis. Obesity and cigarette smoking are well-known risk factors associated breast cancer development. Nicotine known to decrease inflammatory signals also modulates immune responses that favor breast cancer development. However, the mechanisms by which nicotine and obesity contribute to breast cancer remain poorly understood. In this study, we examined potential mechanisms by which nicotine (NIC) and high-fat diet (HFD) promote growth of HCC70 and HCC1806 xenografts from African American (AA) triple negative (TN) breast cancer cells. Immunodeficient mice fed on HFD and treated with NIC generated larger HCC70 and HCC1806 tumors when compared to NIC or HFD alone. Increased xenograft growth in the presence of NIC and HFD was accompanied by higher levels of tissue-resident macrophage markers and anti-inflammatory cytokines including IL4, IL13, and IL10. We further validated the involvement of these players by in vitro and ex vivo experiments. We found a proinflammatory milieu with increased expression of IL6 and IL12 in xenografts with HFD. In addition, nicotine or nicotine plus HFD increased a subset of mammary cancer stem cells (MCSCs) and key adipose browning markers CD137 and TMEM26. Interestingly, there was upregulation of stress-induced pp38 MAPK and pERK1/2 in xenografts exposed to HFD alone or nicotine plus HFD. Scratch-wound assay showed marked reduction in proliferation/migration of nicotine and palmitate-treated breast cancer cells with mecamylamine (MEC), a nicotine acetylcholine receptor (nAchR) antagonist. Furthermore, xenograft development in immune-deficient mice, fed HFD plus nicotine, was reduced upon cotreatment with MEC and SB 203580, a pp38MAPK inhibitor. Our study demonstrates the presence of nicotine and HFD in facilitating an anti-inflammatory tumor microenvironment that influences breast tumor growth. This study also shows potential efficacy of combination therapy in obese breast cancer patients who smoke.


Assuntos
Ração Animal , Anti-Inflamatórios/farmacologia , Neoplasias da Mama/induzido quimicamente , Dieta Hiperlipídica , Nicotina/farmacologia , Animais , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Imidazóis/farmacologia , Inflamassomos , Inflamação , Neoplasias Mamárias Animais/induzido quimicamente , Neoplasias Mamárias Animais/patologia , Mecamilamina/química , Camundongos , Transplante de Neoplasias , Células-Tronco Neoplásicas/metabolismo , Nicotina/química , Nicotina/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Piridinas/farmacologia , Regulação para Cima , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
11.
Nano Lett ; 18(11): 6719-6724, 2018 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-30347160

RESUMO

There is a recent surge of interest in amplification and detection of tiny motion in the growing field of opto- and electromechanics. Here, we demonstrate widely tunable, broad bandwidth, and high gain all-mechanical motion amplifiers based on graphene/silicon nitride (SiNx) hybrids. In these devices, a tiny motion of a large-area SiNx membrane is transduced to a much larger motion in a graphene drum resonator coupled to SiNx. Furthermore, the thermal noise of graphene is reduced (squeezed) through parametric tension modulation. The parameters of the amplifier are measured by photothermally actuating SiNx and interferometrically detecting graphene displacement. We obtain a displacement power gain of 38 dB and demonstrate 4.7 dB of squeezing, resulting in a detection sensitivity of 3.8 [Formula: see text], close to the thermal noise limit of SiNx.

12.
J Gastroenterol Hepatol ; 32(2): 378-387, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27262283

RESUMO

BACKGROUND AND AIM: As best estimates on functional gastrointestinal disorders (FGIDs) prevalence are expected from community studies, which are scanty from Asia, we evaluated the prevalence and risk factors of FGIDs in a rural Indian community. METHODS: House-to-house survey was undertaken by trained interviewers using translated-validated Rome III and hospital anxiety and depression questionnaires. RESULT: Among 3426 subjects ≥ 18 years old from 3 villages in Uttar Pradesh, 84% participated, of whom 80% were finally analyzed. Of these 2774 subjects (age 38.4 ± 16.5 years, 1573 [56.7%] male), 2654 [95.7%] were vegetarian and 120 [4.3%] non-vegetarian. Socioeconomic classes were upper (16.7%), upper middle (15.1%), lower middle (22%), upper lower (22.2%), and lower (24%) using Prasad's Classification; 603 (21.7%) had FGIDs (413 [14.9%] dyspepsia, 75 [2.7%] irritable bowel syndrome (IBS) and 115 [4.1%] dyspepsia-IBS overlap), by Rome III criteria. In subjects with dyspepsia, 49/528 (9%) had epigastric pain, 141 (27%) postprandial distress syndromes (EPS, PDS) and 338 (64%) EPS-PDS overlap. IBS was more often diarrhea than constipation-predominant subtype. On univariate analysis, chewing tobacco, aerated drink, tea/coffee, disturbed sleep, vegetarianism, and anxiety parameters and presence of dyspepsia predicting occurrence of IBS were associated with FGIDs. On multivariate analysis, chewing tobacco, aerated soft drink, tea/coffee, vegetarianism, anxiety parameters, and presence of dyspepsia predicting IBS were significant. CONCLUSION: Functional gastrointestinal disorders, particularly dyspepsia-IBS overlap, are common in rural Indian population; the risk factors included chewing tobacco, aerated soft drink, tea/coffee, vegetarian diet, disturbed sleep, anxiety, and dyspepsia predicting occurrence of IBS.


Assuntos
Gastroenteropatias/epidemiologia , Gastroenteropatias/etiologia , População Rural/estatística & dados numéricos , Adolescente , Adulto , Bebidas Gaseificadas/efeitos adversos , Café/efeitos adversos , Dieta Vegana/efeitos adversos , Dispepsia/etiologia , Feminino , Humanos , Índia/epidemiologia , Síndrome do Intestino Irritável/etiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Inquéritos e Questionários , Chá/efeitos adversos , Uso de Tabaco/efeitos adversos , Adulto Jovem
13.
BMC Cancer ; 16: 559, 2016 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-27473585

RESUMO

BACKGROUND: Breast cancer is a complex heterogeneous disease where many distinct subtypes are found. Younger African American (AA) women often present themselves with aggressive form of breast cancer with unique biology which is very difficult to treat. Better understanding the biology of AA breast tumors could lead to development of effective treatment strategies. Our previous studies indicate that AA but not Caucasian (CA) triple negative (TN) breast cancer cells were sensitive to nitrosative stress-induced cell death. In this study, we elucidate possible mechanisms that contribute to nitric oxide (NO)-induced apoptosis in AA TN breast cancer cells. METHODS: Breast cancer cells were treated with various concentrations of long-acting NO donor, DETA-NONOate and cell viability was determined by trypan blue exclusion assay. Apoptosis was determined by TUNEL and caspase 3 activity as well as changes in mitochondrial membrane potential. Caspase 3 and Bax cleavage, levels of Cu/Zn superoxide dismutase (SOD) and Mn SOD was assessed by immunoblot analysis. Inhibition of Bax cleavage by Calpain inhibitor, and levels of reactive oxygen species (ROS) as well as SOD activity was measured in NO-induced apoptosis. In vitro and in vivo effect of NO treatment on mammary cancer stem cells (MCSCs) was assessed. RESULTS AND DISCUSSION: NO induced mitocondria-mediated apoptosis in all AA but not in CA TN breast cancer cells. We found significant TUNEL-positive cells, cleavage of Bax and caspase-3 activation as well as depolarization mitochondrial membrane potential only in AA TN breast cancer cells exposed to NO. Inhibition of Bax cleavage and quenching of ROS partially inhibited NO-induced apoptosis in AA TN cells. Increase in ROS coincided with reduction in SOD activity in AA TN breast cancer cells. Furthermore, NO treatment of AA TN breast cancer cells dramatically reduced aldehyde dehydrogenase1 (ALDH1) expressing MCSCs and xenograft formation but not in breast cancer cells from CA origin. CONCLUSIONS: Ethnic differences in breast tumors dictate a need for tailoring treatment options more suited to the unique biology of the disease.


Assuntos
Apoptose/efeitos dos fármacos , Compostos Nitrosos/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto , Negro ou Afro-Americano , Família Aldeído Desidrogenase 1 , Animais , Caspase 3/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Immunoblotting , Isoenzimas/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos Nus , Mitocôndrias/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico/farmacologia , Compostos Nitrosos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Retinal Desidrogenase/metabolismo , Superóxido Dismutase/metabolismo , Neoplasias de Mama Triplo Negativas/etnologia , Neoplasias de Mama Triplo Negativas/metabolismo , Proteína X Associada a bcl-2/metabolismo
14.
Exp Cell Res ; 335(1): 1-11, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25911129

RESUMO

The microenvironment of tumor cells is critically involved in tumor development and progression. Tumor-associated fibroblasts (TAFs) represent a major constituent of the tumor stroma. Tumor cells are operative in the activation of TAFs, whereas TAFs in turn contribute to tumor cell malignancy. This report describes mechanisms of communication between fibroblasts and urinary bladder cancer (UBC) cells. Migration of bladder cancer cell lines RT112 and Cal-29, representing two different grades of dedifferentiation, was enhanced by cocultivation with TAFs. Conditioned medium from tumor cells induced the release of interleukin (IL)-8, hepatocyte growth factor (HGF), matrix metalloproteinase-2, granulocyte macrophage colony-stimulating factor, and monocyte chemotactic protein (MCP)-1 by TAFs. Tumor cell-derived IL-1α was identified as a major mediator of these stimulatory effects. Fibroblasts, on the other hand, exerted a migration and invasion stimulating influence on UBC cells. MCP-1 and HGF were shown to promote cell migration of both bladder cancer cell lines.


Assuntos
Quimiocinas/metabolismo , Fibroblastos/patologia , Neoplasias da Bexiga Urinária/patologia , Bexiga Urinária/patologia , Comunicação Celular , Linhagem Celular Tumoral , Movimento Celular , Quimiocina CCL2/metabolismo , Técnicas de Cocultura , Meios de Cultivo Condicionados/farmacologia , Transição Epitelial-Mesenquimal/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Interleucina-1alfa/metabolismo , Interleucina-8/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Invasividade Neoplásica , Células Estromais/patologia
15.
J Cancer Educ ; 31(4): 709-714, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-26687206

RESUMO

Lung cancer is one of the most common causes of cancer mortality among men in India and incidence is increasing, but actually, they are largely preventable diseases. In India, advanced stage at the time of presentation is responsible for high mortality and morbidity and early detection is the only way to reduce it. The purpose of this study is to know the level of awareness of various aspects of lung cancer among college teachers and impact of awareness programmes in its prevention and early detection. This assessment was part of Pink Chain Campaign-a campaign on cancer awareness. During the cancer awareness events in 2011-2013 at various women colleges in different parts in India, pre-test related to lung cancer was followed by awareness programme. Post-test using the same questionnaire was conducted at the end of interactive session, at 6 months and 1 year. A total of 872 out of 985 teachers participated in the study (overall response rate was 88.5 %). Mean age of the study population was 41.6 years (range 26-59 years). There was a significant increase in the level of knowledge regarding lung cancer at 6 months, and this was sustained at 1 year. Among teachers who were just asked yes or no question, 117 teachers (13.4 %) were smokers and 241 teachers (27.6 %) were alcoholics. Magazines and newspapers were sources for knowledge in 50-60 % of teachers, whereas approximately 30 % of teachers were educated by TV and Internet regarding various aspects of lung cancer. Post awareness at 6 months and 1 year, Pink Chain Campaign was the major source of knowledge related to lung cancer in more than 90 % of teachers by continuous and timely update on subject. Post awareness at 6 months and 1 year, there was a significant change in alcohol and smoking habits. Major reasons for not going for check-up were ignorance (83.1 %), fear (30.1 %) and lethargic attitude (29.3 %) initially, but over time, lack of time, lethargic attitude and hesitation became important factors after knowing various aspects of lung cancer. Knowledge of lung cancer was very low among teachers. Overall awareness of risk factors, sign and symptoms, screening modalities of lung cancer has improved in a year along with practices related to smoking and alcohol, but there was not much improvement in people undergoing regular check-ups. To inculcate safe practices in the lifestyle of people, awareness programmes such as the Pink Chain Campaign should be conducted more widely and frequently.


Assuntos
Detecção Precoce de Câncer/psicologia , Docentes/psicologia , Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/prevenção & controle , Adulto , Feminino , Humanos , Neoplasias Pulmonares/psicologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Socioeconômicos , Inquéritos e Questionários
16.
J Lipid Res ; 55(3): 375-84, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24443561

RESUMO

Follistatin (Fst) functions to bind and neutralize the activity of members of the transforming growth factor-ß superfamily. Fst has a well-established role in skeletal muscle, but we detected significant Fst expression levels in interscapular brown and subcutaneous white adipose tissue, and further investigated its role in adipocyte biology. Fst expression was induced during adipogenic differentiation of mouse brown preadipocytes and mouse embryonic fibroblasts (MEFs) as well as in cold-induced brown adipose tissue from mice. In differentiated MEFs from Fst KO mice, the induction of brown adipocyte proteins including uncoupling protein 1, PR domain containing 16, and PPAR gamma coactivator-1α was attenuated, but could be rescued by treatment with recombinant FST. Furthermore, Fst enhanced thermogenic gene expression in differentiated mouse brown adipocytes and MEF cultures from both WT and Fst KO groups, suggesting that Fst produced by adipocytes may act in a paracrine manner. Our microarray gene expression profiling of WT and Fst KO MEFs during adipogenic differentiation identified several genes implicated in lipid and energy metabolism that were significantly downregulated in Fst KO MEFs. Furthermore, Fst treatment significantly increases cellular respiration in Fst-deficient cells. Our results implicate a novel role of Fst in the induction of brown adipocyte character and regulation of energy metabolism.


Assuntos
Adipócitos/metabolismo , Tecido Adiposo Marrom/metabolismo , Diferenciação Celular/genética , Metabolismo Energético/genética , Folistatina/genética , Perfilação da Expressão Gênica , Adipócitos/citologia , Tecido Adiposo Marrom/citologia , Animais , Carbonil Cianeto p-Trifluormetoxifenil Hidrazona/farmacologia , Células Cultivadas , Temperatura Baixa , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Feminino , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Folistatina/metabolismo , Immunoblotting , Metabolismo dos Lipídeos/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Análise de Sequência com Séries de Oligonucleotídeos , Consumo de Oxigênio/efeitos dos fármacos , Ionóforos de Próton/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Termogênese/genética
17.
Biochem Biophys Res Commun ; 452(3): 361-8, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25159848

RESUMO

Protease inhibitors have been known to confer multiple stress tolerance in transgenic plants. We have assessed growth of yeast (Pichia pastoris GS115) strains expressing inhibitory repeat domains (PpIRD(+)) of previously characterized Capsicum annuum protease inhibitors under high salt, heavy metal and oxidative stress. PpIRD(+) strains exhibited multiple stress tolerance and showed differential molecular responses at transcriptional and translational level on exposure to stress inducing agents like heavy metal, high salt and H2O2. PpIRD(+) strains display significant reduction in metacaspase (Yca1) activity, the key enzyme in apoptosis, indicates the possibility of cross reactivity of IRDs (serine protease inhibitor) with cysteine proteases. PpIRD(+) and Saccharomyces cerevisiae knockout with Yca1 (ΔYca1) strain showed similar growth characteristics under stress, which indicated the delayed senescence due to cellular metacaspase inhibition. Molecular docking study showed a close proximity of IRDs reactive site and the active site of metacaspase in the complex that signified their strong interactions. Maintenance of GAPDH activity, primary target of metacaspase, in PpIRD(+) strain evidenced the inhibition of metacaspase activity and survival of these cells under stress. This report demonstrates a potential molecular mechanism of protease inhibitor-based multiple stress tolerance in yeast strains.


Assuntos
Caspases/química , Regulação Fúngica da Expressão Gênica , Pichia/genética , Saccharomyces cerevisiae/genética , Inibidores de Serina Proteinase/genética , Adaptação Fisiológica , Capsicum/química , Capsicum/metabolismo , Caspases/deficiência , Caspases/genética , Caspases/metabolismo , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/genética , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/metabolismo , Peróxido de Hidrogênio/farmacologia , Metais Pesados/toxicidade , Viabilidade Microbiana , Simulação de Acoplamento Molecular , Pichia/efeitos dos fármacos , Pichia/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Salinidade , Inibidores de Serina Proteinase/biossíntese , Transdução de Sinais , Cloreto de Sódio/farmacologia , Estresse Fisiológico
18.
Chem Commun (Camb) ; 60(30): 4092-4095, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38511970

RESUMO

Leishmania donovani are intracellular, human blood parasites that cause visceral leishmaniasis or kala-azar. Cell-penetrating peptides (CPPs) have been shown to modulate intracellular processes and cargo delivery, whereas host defense peptides (HDPs) promote proliferation of both naïve and antigen activated CD4+ T-cells. We report newly designed tripeptides that were able to trigger proinflammatory cytokine (IL-12 and IFN-γ) secretion by CD4+CD44+ T-cells in response to Leishmania donovani infection. These peptides can be used to induce antigen specific TH1 responses to combat obstacles of cytotoxicity and drug resistance associated with current anti-leishmanial drugs. Furthermore, these peptides can also be used as adjuvants to develop an effective immunoprophylactic approach for immunity restoration against visceral leishmaniasis.


Assuntos
Leishmania donovani , Leishmaniose Visceral , Humanos , Interleucina-12 , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/parasitologia , Linfócitos T , Imunidade , Linfócitos T CD4-Positivos
19.
J Pers Med ; 14(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38541022

RESUMO

Glucagon-like peptide-1 (GLP-1) is an incretin hormone known for its pivotal role in enhancing insulin secretion and reducing glucagon release from the pancreas. Diabetic nephropathy, which is characterized by albuminuria, represents a significant microvascular complication of diabetes. Most of the previous studies mainly focused on the therapeutic renal protective effect in clinical trials after the administration of GLP-1 receptor agonists (GLP-1 RAs), rather than before administration. Hence, this study aimed to investigate the association between fasting plasma GLP-1 levels and albuminuria before GLP-1 RA administration. A cross-sectional study was designed to evaluate the association between fasting plasma GLP-1 levels and albuminuria in patients with type 2 diabetes mellitus (T2DM). A cohort of 68 participants with T2DM was analyzed using data collected at Wonkwang University Hospital in Iksan, Korea. Logistic regression analysis was employed to determine the odds ratio (OR) and 95% confidence interval (CI) of the incidence of albuminuria between two groups categorized by fasting GLP-1 levels, low (Group L) and high GLP-1 (Group H). The OR (95% CI) for the incidence of albuminuria comparing Group L with Group H of fasting plasma GLP-1 levels was 3.41 (1.16-10.02), p = 0.03 after adjustment for relevant variables including age, gender, fasting plasma glucose, HbA1c, C-peptide, creatinine, and medication use [angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs), sodium-glucose cotransporter-2 (SGLT-2) inhibitors, and dipeptidyl peptidase-4 (DPP-4) inhibitors]. When analyzed as a continuous variable, each 1 pmol/L reduction in fasting plasma GLP-1 levels was associated with an OR (95% CI) of 1.67 (1.17-1.87), p = 0.02, following full adjustment. These results highlight a negative association between fasting plasma GLP-1 levels and the incidence of albuminuria in Korean patients with T2DM, before GLP-1 RA administration. These findings suggest that endogenous GLP-1 may have a beneficial impact in mitigating albuminuria.

20.
EMBO Mol Med ; 16(1): 185-217, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38177535

RESUMO

Japanese encephalitis virus (JEV) pathogenesis is driven by a combination of neuronal death and neuroinflammation. We tested 42 FDA-approved drugs that were shown to induce autophagy for antiviral effects. Four drugs were tested in the JE mouse model based on in vitro protective effects on neuronal cell death, inhibition of viral replication, and anti-inflammatory effects. The antipsychotic phenothiazines Methotrimeprazine (MTP) & Trifluoperazine showed a significant survival benefit with reduced virus titers in the brain, prevention of BBB breach, and inhibition of neuroinflammation. Both drugs were potent mTOR-independent autophagy flux inducers. MTP inhibited SERCA channel functioning, and induced an adaptive ER stress response in diverse cell types. Pharmacological rescue of ER stress blocked autophagy and antiviral effect. MTP did not alter translation of viral RNA, but exerted autophagy-dependent antiviral effect by inhibiting JEV replication complexes. Drug-induced autophagy resulted in reduced NLRP3 protein levels, and attenuation of inflammatory cytokine/chemokine release from infected microglial cells. Our study suggests that MTP exerts a combined antiviral and anti-inflammatory effect in JEV infection, and has therapeutic potential for JE treatment.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Animais , Camundongos , Vírus da Encefalite Japonesa (Espécie)/fisiologia , Metotrimeprazina/farmacologia , Metotrimeprazina/uso terapêutico , Doenças Neuroinflamatórias , Encefalite Japonesa/tratamento farmacológico , Encefalite Japonesa/patologia , Antivirais/farmacologia , Antivirais/uso terapêutico , Autofagia , Anti-Inflamatórios/uso terapêutico
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