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1.
J Assoc Physicians India ; 72(7): 25-28, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38990583

RESUMO

BACKGROUND: Recent research has shown that low serum levels of magnesium are often linked to both microvascular and macrovascular complications in individuals with diabetes mellitus. Hence, monitoring of serum magnesium levels is needed in diabetic patients. Furthermore, the addition of magnesium through supplementation may present a novel therapeutic strategy for mitigating vascular complications in individuals with diabetes. OBJECTIVES: To assess the prevalence of hypomagnesemia in type 2 diabetes mellitus patients and to assess the association between hypomagnesemia and microvascular complications of diabetes mellitus in a tertiary care hospital in North Kerala. MATERIALS AND METHODS: An analytical cross-sectional study was conducted at a tertiary care hospital involving 230 diabetic patients receiving outpatient and inpatient care in the Department of Internal Medicine at Government Medical College, Kozhikode, Kerala. The study took place from January 2018 to December 2018, during which serum magnesium levels were assessed and analyzed in relation to the patients' microvascular complications and glycemic control. RESULTS: We observed that 19.13% of the participants had hypomagnesemia. This condition was found to be more common among older individuals with diabetes, as indicated by a p-value of 0.022. However, there were no significant differences in serum magnesium levels based on gender (p-value 0.18), body mass index (BMI) (p-value 0.223), or the duration of diabetes (p-value 0.36). The prevalence of diabetic retinopathy, diabetic neuropathy, and diabetic nephropathy was higher in diabetics with hypomagnesemia than their counterparts with normal magnesium, with a p-value of 0.001, 0.001, and 0.001, respectively. There was a significant negative correlation obtained between serum magnesium and glycated hemoglobin (HbA1C) values (Pearson coefficient = -0.240 and p-value = <0.01) and fasting blood sugar (FBS) values (Pearson coefficient = -0.265 and p-value = <0.01). CONCLUSION: Hypomagnesemia is negatively correlated with HbA1C and FBS but not related to duration of diabetes and gender. The prevalence of microvascular complications was higher among the diabetics with hypomagnesemia.


Assuntos
Diabetes Mellitus Tipo 2 , Magnésio , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Masculino , Feminino , Estudos Transversais , Pessoa de Meia-Idade , Magnésio/sangue , Prevalência , Deficiência de Magnésio/epidemiologia , Deficiência de Magnésio/sangue , Deficiência de Magnésio/complicações , Idoso , Índia/epidemiologia , Adulto , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/etiologia , Angiopatias Diabéticas/sangue , Hemoglobinas Glicadas/análise
2.
Mol Ther ; 30(1): 485-500, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34450249

RESUMO

Serine/threonine kinase 3 (STK3) is an essential member of the highly conserved Hippo tumor suppressor pathway that regulates Yes-associated protein 1 (YAP1) and TAZ. STK3 and its paralog STK4 initiate a phosphorylation cascade that regulates YAP1/TAZ inhibition and degradation, which is important for regulated cell growth and organ size. Deregulation of this pathway leads to hyperactivation of YAP1 in various cancers. Counter to the canonical tumor suppression role of STK3, we report that in the context of prostate cancer (PC), STK3 has a pro-tumorigenic role. Our investigation started with the observation that STK3, but not STK4, is frequently amplified in PC. Additionally, high STK3 expression is associated with decreased overall survival and positively correlates with androgen receptor (AR) activity in metastatic castrate-resistant PC. XMU-MP-1, an STK3/4 inhibitor, slowed cell proliferation, spheroid growth, and Matrigel invasion in multiple models. Genetic depletion of STK3 decreased proliferation in several PC cell lines. In a syngeneic allograft model, STK3 loss slowed tumor growth kinetics in vivo, and biochemical analysis suggests a mitotic growth arrest phenotype. To further probe the role of STK3 in PC, we identified and validated a new set of selective STK3 inhibitors, with enhanced kinase selectivity relative to XMU-MP-1, that inhibited tumor spheroid growth and invasion. Consistent with the canonical role, inhibition of STK3 induced cardiomyocyte growth and had chemoprotective effects. Our results indicate that STK3 has a non-canonical role in PC progression and that inhibition of STK3 may have a therapeutic potential for PC that merits further investigation.


Assuntos
Neoplasias da Próstata , Proteínas Serina-Treonina Quinases , Linhagem Celular Tumoral , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Neoplasias da Próstata/genética , Proteínas Serina-Treonina Quinases/genética , Serina/farmacologia , Serina-Treonina Quinase 3 , Transdução de Sinais
3.
Biomacromolecules ; 23(9): 3866-3874, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-35977724

RESUMO

Gold nanorods (GNRs) are widely used in various biomedical applications such as disease imaging and therapy due to their unique plasmonic properties. To improve their bioavailability, GNRs often need to be coated with hydrophilic polymers so as to impart stealth properties. Poly(ethylene glycol) (PEG) has been long used as such a coating material for GNRs. However, there is increasing acknowledgement that the amphiphilic nature of PEG facilitates its interaction with protein molecules, leading to immune recognition and consequent side effects. This has motivated the search for new classes of low-fouling polymers with high hydrophilicity as alternative low-fouling surface coating materials for GNRs. Herein, we report the synthesis, characterization, and application of GNRs coated with highly hydrophilic sulfoxide-containing polymers. We investigated the effect of the sulfoxide polymer coating on the cellular uptake and in vivo circulation time of the GNRs and compared these properties with pegylated GNR counterparts. The photothermal effect and photoacoustic imaging of these polymer-coated GNRs were also explored, and the results show that these GNRs are promising as nanotheranostic particles for the treatment of cancer.


Assuntos
Ouro , Nanotubos , Ouro/farmacologia , Polímeros , Medicina de Precisão , Sulfóxidos
4.
Proc Natl Acad Sci U S A ; 116(1): 148-157, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30587589

RESUMO

The epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC) formation are two paramount processes driving tumor progression, therapy resistance, and cancer metastasis. Recent experiments show that cells with varying EMT and CSC phenotypes are spatially segregated in the primary tumor. The underlying mechanisms generating such spatiotemporal dynamics in the tumor microenvironment, however, remain largely unexplored. Here, we show through a mechanism-based dynamical model that the diffusion of EMT-inducing signals such as TGF-ß, together with noncell autonomous control of EMT and CSC decision making via the Notch signaling pathway, can explain experimentally observed disparate localization of subsets of CSCs with varying EMT phenotypes in the tumor. Our simulations show that the more mesenchymal CSCs lie at the invasive edge, while the hybrid epithelial/mesenchymal (E/M) CSCs reside in the tumor interior. Further, motivated by the role of Notch-Jagged signaling in mediating EMT and stemness, we investigated the microenvironmental factors that promote Notch-Jagged signaling. We show that many inflammatory cytokines such as IL-6 that can promote Notch-Jagged signaling can (i) stabilize a hybrid E/M phenotype, (ii) increase the likelihood of spatial proximity of hybrid E/M cells, and (iii) expand the fraction of CSCs. To validate the predicted connection between Notch-Jagged signaling and stemness, we knocked down JAG1 in hybrid E/M SUM149 human breast cancer cells in vitro. JAG1 knockdown significantly restricted tumor organoid formation, confirming the key role that Notch-Jagged signaling can play in tumor progression. Together, our integrated computational-experimental framework reveals the underlying principles of spatiotemporal dynamics of EMT and CSCs.


Assuntos
Células-Tronco Neoplásicas/fisiologia , Microambiente Tumoral/fisiologia , Neoplasias da Mama/patologia , Citocinas/metabolismo , Transição Epitelial-Mesenquimal/fisiologia , Feminino , Técnicas de Silenciamento de Genes , Humanos , Células Neoplásicas Circulantes/patologia , Células-Tronco Neoplásicas/citologia , Fenótipo , Receptores Notch/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo
5.
Opt Lett ; 46(5): 1033-1036, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33649650

RESUMO

A method for fabricating bio-inspired scattering substrates based on polydimethylsiloxane (PDMS) for spatially incoherent random lasing is presented. The leaves of monstera and piper sarmentosum plants are used to mold PDMS polymer to form wrinkle-like scattering substrates, which are then used with a liquid gain medium for random lasing. Scattering is attributed to the surface roughness (Sa) of the samples. The rougher sample with 5.2 µm Sa shows a two-mode stable lasing with a 2 nm linewidth and a lower threshold fluence of 0.2mJ/cm2 compared to the sample with smaller Sa (3.6 µm) with a linewidth of 5 nm and a threshold fluence of 0.5mJ/cm2. The waveguide theory substantiates the results of incoherent random lasing through a relation between the microstructure feature size and the mean free path. Power Fourier transform analysis is used to deduce the resonant cavity length of 180 µm in the rougher sample, and the observed variations in cavity length with Sa validate the optical feedback. PDMS being hydrophobic, the scattering substrate can be reused by wiping off the gain medium. This Letter paves the way for facile fabrication methods of bio-inspired random lasers for sensing and imaging applications.

6.
Mol Pharm ; 18(6): 2142-2160, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34010004

RESUMO

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease, for which no effective treatment is yet available to either slow or terminate it. Recent advances in gene therapy renew hope for developing an effective approach to control this disease. Non-viral vectors, such as lipid- and polymer-based nanoparticles, cationic polymers, and exosomes, can effectively transfer genes into primary neurons. The resulting gene expression can be long-term, stable, and without immunological complications, which is essential for the effective management of neurological disorders. This Review will first describe the current research and clinical stage of novel therapies for ALS. It will then touch on the journey of non-viral vector use in ALS, subsequently highlighting the application of non-viral vector-mediated gene therapy. The bottlenecks in the translation of non-viral vectors for ALS treatment are also discussed, including the biological barriers of systemic administration and the issues of "when, where, and how much?" for effective gene delivery. The prospect of employing emerging techniques, such as CRISPR-Cas9 gene editing, stem cell methodology, and low-intensity focused ultrasound for fueling the transport of non-viral vectors to the central nervous system for personalized gene therapy, is briefly discussed in the context of ALS. Despite the challenging road that lies ahead, with the current expansion in interest and technological advancement in non-viral vector-delivered gene therapy for ALS, we hold hope that the field is headed toward a positive future.


Assuntos
Esclerose Lateral Amiotrófica/terapia , Técnicas de Transferência de Genes/efeitos adversos , Terapia Genética/métodos , Vetores Genéticos/administração & dosagem , Esclerose Lateral Amiotrófica/genética , Animais , Sistemas CRISPR-Cas/genética , Células Cultivadas , Ensaios Clínicos Fase III como Assunto , Modelos Animais de Doenças , Técnicas de Transferência de Genes/tendências , Terapia Genética/efeitos adversos , Terapia Genética/tendências , Vetores Genéticos/efeitos adversos , Humanos , Nanopartículas/administração & dosagem , Cultura Primária de Células
7.
Xenotransplantation ; 28(3): e12680, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33619844

RESUMO

BACKGROUND: Thrombosis is a known consequence of intraportal islet transplantation, particularly for xenogeneic islets. To define the origins of thrombosis after islet xenotransplantation and relate it to early inflammation, we examined porcine islets transplanted into non-human primates using a dual-transplant model to directly compare islet characteristics. METHODS: α1,3-Galactosyltransferase gene-knockout (GTKO) islets with and without expression of the human complement regulatory transgene CD46 (hCD46) were studied. Biologically inert polyethylene microspheres were used to examine the generic pro-thrombotic effects of particle embolization. Immunohistochemistry was performed 1 and 24 hours after transplantation. RESULTS: Xeno-islet transplantation activated both extrinsic and intrinsic coagulation pathways. The intrinsic pathway was also initiated by microsphere embolization, while extrinsic pathway tissue factor (TF) and platelet aggregation were more specific to engrafted islets. hCD46 expression significantly reduced TF, platelet, fibrin, and factor XIIIa accumulation in and around islets but did not alter intrinsic factor activation. Layers of TF+ cells emerged around islets within 24 hours, particularly co-localized with vimentin, and identified as CD3+ and CD68+ cells inflammatory cells. CONCLUSIONS: These findings detail the origins of thrombosis following islet xenotransplantation, relate it to early immune activation, and suggest a role for transgenic hCD46 expression in its mitigation. Layers of TF-positive inflammatory cells and fibroblasts around islets at 24 hours may have important roles in the progressive events of thrombosis, inflammatory cell recruitment, rejection, and the ultimate outcome of transplanted grafts. These suggest that the strategies targeting these elements could yield more progress toward successful xenogeneic islet engraftment and survival.


Assuntos
Transplante das Ilhotas Pancreáticas , Animais , Xenoenxertos , Inflamação , Suínos , Transgenes , Transplante Heterólogo
8.
Scand J Gastroenterol ; 56(5): 588-593, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33730978

RESUMO

BACKGROUND: A subset of chronic pancreatitis patients respond poorly to pancreatic enzyme replacement therapy. Small intestinal bacterial overgrowth (SIBO) is considered to be one of the major reasons for this poor response. Previous studies have reported a wide range of prevalence of SIBO in patients with chronic pancreatitis. We aimed to assess the prevalence of SIBO in chronic pancreatitis using quantitative jejunal aspirate culture and glucose hydrogen breath test (GHBT). The sensitivity and specificity of GHBT for the diagnosis of SIBO in chronic pancreatitis were also estimated. METHODS: Newly diagnosed chronic pancreatitis patients were recruited into the study. A detailed history and relevant laboratory tests were done. All patients underwent an endoscopy and jejunal fluid aspiration for bacterial cultures and GHBT to detect SIBO. The results of GHBT were compared with jejunal fluid aspirate culture. RESULTS: The jejunal aspirate culture was positive in 18/48 (37.5%) patients while the GHBT showed that 14/48 (29%) patients had SIBO. The sensitivity, specificity, positive and negative predictive value of GHBT in our study was 44.4, 80, 57.14 and 70.59%, respectively. CONCLUSIONS: SIBO is not uncommon in chronic pancreatitis patients. One-third of our study population had SIBO. GHBT has low sensitivity but had high specificity in the diagnosis of SIBO in chronic pancreatitis.


Assuntos
Infecções Bacterianas , Pancreatite Crônica , Testes Respiratórios , Glucose , Humanos , Hidrogênio , Intestino Delgado , Pancreatite Crônica/diagnóstico
9.
Environ Res ; 201: 111614, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34216610

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are a toxic and ubiquitous class of environmental chemicals, products of fuel combustion from human and natural sources. The objective of this study was to identify vulnerable populations for high PAH exposure and variability, to better understand where to target PAH exposure reduction initiatives. Urinary metabolite data were collected from 9517 individuals from the U.S. CDC National Health and Nutrition Examination Survey years 2005-2014 for four parental PAHs naphthalene, fluorene, phenanthrene, and pyrene. We utilized these urinary biomarkers to estimate PAH intake, and regression models were fit for multiple demographic and lifestyle variables, to determine variable effects, interactions, odds of high versus low PAH intake. Smoking and secondhand smoke exposure accounted for the largest PAH intake rate variability (25.62%), and there were strongest interactions between race/ethnicity and smoking or SHS exposure, reflected in a much greater contribution of smoking to PAH intake in non-Hispanic Whites as compared to other races/ethnicities. Increased odds of high PAH intake were seen in older age groups, obese persons, college graduates, midrange incomes, smokers, and those who were SHS exposed. Among the non-smoking population, effects of other demographic factors lessened, suggesting a highly interactive nature. Our results suggest that there are demographic subpopulations with high PAH intake as a result of different smoking behaviors and potentially other exposures. This has human health, environmental justice, and regulatory implications wherein smoking cessation programs, SHS exposure regulations, and public health initiatives could be better targeted towards vulnerable subpopulations to meaningfully reduce PAH exposures.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluição por Fumaça de Tabaco , Adulto , Idoso , Humanos , Estilo de Vida , Inquéritos Nutricionais , Poluição por Fumaça de Tabaco/efeitos adversos , Populações Vulneráveis
10.
IEEE Sens J ; 21(20): 22758-22766, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35582121

RESUMO

SARS-CoV-2 nucleocapsid protein-based COVID-19 diagnosis is a promising alternative to the high-priced, time-consuming, and labor-intensive RT-PCR tests. Here, we developed a rapid, dip-type, wash-free plasmonic fiber optic absorbance biosensor (P-FAB) strategy for the point-of-care detection of SARS-CoV-2 N-protein, expressed abundantly during the infection. P-FAB involves a sandwich assay with plasmonic labels on the surface of a U-bent fiber optic sensor probe with a high evanescent wave absorbance (EWA) sensitivity. The SARS-CoV-2 N-protein is quantified in terms of the change in the intensity of the light propagating through the U-bent sensor probe coupled to a green LED and a photodetector. Firstly, the optical fiber material (silica vs. polymeric optical fiber), was evaluated to realize a sensitive sensor platform. The optimal size of AuNP labels (20, 40, and 60 nm) to achieve high sensitivity and a lower limit of detection (LoD) was investigated. Following the P-FAB strategy, fused silica/glass optical fiber (GOF) U-bent senor probe and citrate-capped AuNP labels (size ~40 nm) gave rise to an LoD down to ~2.5 ng/mL within 10 mins of read-out time. Further, studies on development and validation of a point of care (PoC) read-out device, and preclinical studies are in progress.

11.
Carcinogenesis ; 41(12): 1648-1659, 2020 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-32747956

RESUMO

Emerging evidence suggests the role of environmental chemicals, in particular endocrine-disrupting chemicals (EDCs), in progression of breast cancer and treatment resistance, which can impact survival outcomes. However, most research tends to focus on tumor etiology and the effect of single chemicals, offering little insight into the effects of realistic complex mixture exposures on tumor progression. Herein, we investigated the effect of a polycyclic aromatic hydrocarbon (PAH)-enriched EDC mixture in a panel of normal and breast cancer cells and in a tumor organoid model. Cells or organoids in culture were treated with EDC mixture at doses estimated from US adult intake of the top four PAH compounds within the mixture from the National Health and Nutrition Examination Survey database. We demonstrate that low-dose PAH mixture (6, 30 and 300 nM) increased aryl hydrocarbon receptor (AhR) expression and CYP activity in estrogen receptor (ER) positive but not normal mammary or ER-negative breast cancer cells, and that upregulated AhR signaling corresponded with increased cell proliferation and expression of antiapoptotic and antioxidant proteins XIAP and SOD1. We employed a mathematical model to validate PAH-mediated increases in AhR and XIAP expression in the MCF-7 ER-positive cell line. Furthermore, the PAH mixture caused significant growth increases in ER-negative breast cancer cell derived 3D tumor organoids, providing further evidence for the role of a natural-derived PAH mixture in enhancing a tumor proliferative phenotype. Together, our integrated cell signaling, computational and phenotype analysis reveals the underlying mechanisms of EDC mixtures in breast cancer progression and survival.


Assuntos
Apoptose , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Disruptores Endócrinos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/farmacologia , Receptores de Hidrocarboneto Arílico/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Feminino , Humanos , Receptores de Hidrocarboneto Arílico/genética , Células Tumorais Cultivadas
12.
Breast Cancer Res Treat ; 180(1): 207-217, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31960171

RESUMO

PURPOSE: Inflammatory breast cancer (IBC) is an aggressive variant for which axillary lymph node (LN) dissection following neoadjuvant chemotherapy (NACT) remains standard of care. But with increasingly effective systemic therapy, it is unclear whether more limited axillary surgery may be appropriate in some IBC patients. We sought to examine whether extent of axillary LN surgery was associated with overall survival (OS) for IBC. METHODS: Female breast cancer patients with non-metastatic IBC (cT4d) diagnosed 2010-2014 were identified in the National Cancer Data Base. Cox proportional hazards modeling was used to estimate the association between extent of axillary surgery (≤ 9 vs ≥ 10 LNs removed) and OS after adjusting for covariates, including post-NACT nodal status (ypN0 vs ypN1-3) and radiotherapy receipt (yes/no). RESULTS: 3471 patients were included: 597 (17.2%) had cN0 disease, 1833 (52.8%) had cN1 disease, and 1041 (30%) had cN2-3 disease. 49.9% of cN0 patients were confirmed to be ypN0 on post-NACT surgical pathology. Being ypN0 (vs ypN1-3) was associated with improved adjusted OS for all patients. Radiotherapy was associated with improved adjusted OS for cN1 and cN2-3 patients but not for cN0 patients. Regardless of ypN status, there was a trend towards improved adjusted OS with having ≥ 10 (vs ≤ 9) LNs removed for cN2-3 patients (HR 0.78, 95% CI 0.60-1.01, p = 0.06) but not for cN0 patients (p = 0.83). CONCLUSIONS: A majority of IBC patients in our study presented with node-positive disease, and for those presenting with cN2-3 disease, more extensive axillary surgery is potentially associated with improved survival. For cN0 patients, however, more extensive axillary surgery was not associated with a survival benefit, suggesting an opportunity for more personalized care.


Assuntos
Axila/patologia , Axila/cirurgia , Neoplasias Inflamatórias Mamárias/patologia , Neoplasias Inflamatórias Mamárias/cirurgia , Linfonodos/patologia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais , Terapia Combinada , Feminino , Humanos , Neoplasias Inflamatórias Mamárias/etiologia , Neoplasias Inflamatórias Mamárias/mortalidade , Pessoa de Meia-Idade , Terapia Neoadjuvante , Prognóstico , Resultado do Tratamento
13.
Breast Cancer Res Treat ; 180(2): 385-395, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32043194

RESUMO

PURPOSE: Inflammatory breast cancer (IBC) is an aggressive form of breast cancer with elevated metastatic potential, characterized by tumor emboli in dermal and parenchymal lymph vessels. This study has investigated the hypothesis that TGFß signaling is implicated in the molecular biology of IBC. METHODS: TGFß1-induced cell motility and gene expression patterns were investigated in three IBC and three non-IBC (nIBC) cell lines. Tissue samples from IBC and nIBC patients were investigated for the expression of nuclear SMAD2, SMAD3, and SMAD4. SMAD protein levels were related to gene expression data. RESULTS: TGFß1-induced cell motility was strongly abrogated in IBC cells (P = 0.003). Genes differentially expressed between IBC and nIBC cells post TGFß1 exposure revealed attenuated expression of SMAD3 transcriptional regulators, but overexpression of MYC target genes in IBC. IBC patient samples demonstrated a near absence of SMAD3 and -4 expression in the primary tumor compared to nIBC patient samples (P < 0.001) and a further reduction of staining intensity in tumor emboli. Integration of gene and protein expression data revealed that a substantial fraction of the IBC signature genes correlated with SMAD3 and these genes are indicative of attenuated SMAD3 signaling in IBC. CONCLUSION: We demonstrate attenuated SMAD3 transcriptional activity and SMAD protein expression in IBC, together with obliterated TGFß1-induced IBC cell motility. The further reduction of nuclear SMAD expression levels in tumor emboli suggests that the activity of these transcription factors is involved in the metastatic dissemination of IBC cells, possibly by enabling collective invasion after partial EMT.


Assuntos
Movimento Celular , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Neoplasias Inflamatórias Mamárias/patologia , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteína Smad3/genética , Fator de Crescimento Transformador beta1/metabolismo , Linhagem Celular Tumoral , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Neoplasias Inflamatórias Mamárias/genética , Neoplasias Inflamatórias Mamárias/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Transdução de Sinais , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/genética
14.
Soft Matter ; 16(17): 4220-4233, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32296794

RESUMO

In recent decades, there has been a need for novel advancement of sustainable non-fluorinated polymer electrolyte membranes for proton exchange membrane fuel cell (PEMFC) applications. The set forth strategy aims to ameliorate proton conduction of sulfonated polyethersulfone (SPES) polymer membranes with a distinct mixture of barium cerate (BCO) and neodymium-doped barium cerate (BCNO) perovskites developing cationic composite membranes (CCMs) prepared through a technique of solvent casting. The CCMs were subjected to analysis of their mechanical, structural, chemical compositional, thermal, morphological, oxidative, physicochemical, electrochemical and fuel cell polarization performance respectively. Acceptor doping of the trivalent neodymium group at the B site of BCO increases the number of oxygen vacancies and improves ionic conduction. The CCM of neodymium-doped barium cerate demonstrates a higher proton conductivity of 42.2 mS cm-1 with a lower activation energy of 6.80 kJ mol-1 at 80 °C. The maximum current density and power density with the OCV of 0.93 V for the neodymium-doped barium cerate membrane are 397 mA cm-2 and 117 mW cm-2, which is 1.8 times greater than that of the pure SPES membrane. On the basis of polarization performance, the SPES membrane with neodymium-doped barium cerate has great potential in highly-efficient PEMFC applications.

15.
Xenotransplantation ; 26(6): e12540, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31219218

RESUMO

BACKGROUND: Membrane cofactor protein CD46 attenuates the complement cascade by facilitating cleavage of C3b and C4b. In solid organ xenotransplantation, organs expressing CD46 have been shown to resist hyperacute rejection. However, the incremental value of human CD46 expression for islet xenotransplantation remains poorly defined. METHODS: This study attempted to delineate the role of CD46 in early neonatal porcine islet engraftment by comparing Gal-knocked out (GKO) and hCD46-transgenic (GKO/CD46) islets in a dual transplant model. Seven rhesus macaques underwent dual transplant and were sacrificed at 1 hour (n = 4) or 24 hours (n = 3). Both hemilivers were recovered and fixed for immunohistochemistry (CD46, insulin, neutrophil elastase, platelet, IgM, IgG, C3d, C4d, CD68, Caspase 3). Quantitative immunohistochemical analysis was performed using the Aperio Imagescope. RESULTS: Within 1 hour of intraportal infusion of xenografts, no differences were observed between the two types of islets in terms of platelet, antibody, or complement deposition. Cellular infiltration and islet apoptotic activity were also similar at 1 hour. At 24 hours, GKO/CD46 islets demonstrated significantly less platelet deposition (P = 0.01) and neutrophil infiltration (P = 0.01) compared to GKO islets. In contrast, C3d (P = 0.38) and C4d (P = 0.45) deposition was equal between the two genotypes. CONCLUSIONS: Our findings suggest that expression of hCD46 on NPIs potentially provides a measurable incremental survival advantage in vivo by reducing early thrombo-inflammatory events associated with instant blood-mediated inflammatory reaction (IBMIR) following intraportal islet infusion.


Assuntos
Ativação do Complemento/imunologia , Rejeição de Enxerto/imunologia , Proteína Cofatora de Membrana/imunologia , Transplante Heterólogo , Animais , Animais Geneticamente Modificados/imunologia , Anticorpos/imunologia , Humanos , Inflamação/imunologia , Ilhotas Pancreáticas/imunologia , Transplante das Ilhotas Pancreáticas/métodos , Macaca mulatta/imunologia , Transplante Heterólogo/métodos , Transplantes/imunologia
16.
Br J Nutr ; 121(12): 1389-1397, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31006420

RESUMO

India has the second largest number of people with type 2 diabetes (T2D) globally. Epidemiological evidence indicates that consumption of white rice is positively associated with T2D risk, while intake of brown rice is inversely associated. Thus, we explored the effect of substituting brown rice for white rice on T2D risk factors among adults in urban South India. A total of 166 overweight (BMI ≥ 23 kg/m2) adults aged 25-65 years were enrolled in a randomised cross-over trial in Chennai, India. Interventions were a parboiled brown rice or white rice regimen providing two ad libitum meals/d, 6 d/week for 3 months with a 2-week washout period. Primary outcomes were blood glucose, insulin, glycosylated Hb (HbA1c), insulin resistance (homeostasis model assessment of insulin resistance) and lipids. High-sensitivity C-reactive protein (hs-CRP) was a secondary outcome. We did not observe significant between-group differences for primary outcomes among all participants. However, a significant reduction in HbA1c was observed in the brown rice group among participants with the metabolic syndrome (-0·18 (se 0·08) %) relative to those without the metabolic syndrome (0·05 (se 0·05) %) (P-for-heterogeneity = 0·02). Improvements in HbA1c, total and LDL-cholesterol were observed in the brown rice group among participants with a BMI ≥ 25 kg/m2 compared with those with a BMI < 25 kg/m2 (P-for-heterogeneity < 0·05). We observed a smaller increase in hs-CRP in the brown (0·03 (sd 2·12) mg/l) compared with white rice group (0·63 (sd 2·35) mg/l) (P = 0·04). In conclusion, substituting brown rice for white rice showed a potential benefit on HbA1c among participants with the metabolic syndrome and an elevated BMI. A small benefit on inflammation was also observed.


Assuntos
Diabetes Mellitus Tipo 2/etiologia , Dieta/métodos , Síndrome Metabólica/complicações , Oryza/efeitos adversos , Sobrepeso/complicações , Adulto , Idoso , Glicemia/análise , Índice de Massa Corporal , Proteína C-Reativa/análise , Estudos Cross-Over , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Hemoglobinas Glicadas/análise , Humanos , Índia/epidemiologia , Insulina/sangue , Resistência à Insulina , Masculino , Síndrome Metabólica/sangue , Pessoa de Meia-Idade , Sobrepeso/sangue , Fatores de Risco , Adulto Jovem
17.
J Therm Biol ; 74: 149-159, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29801621

RESUMO

Exposure of Culex quinquefasciatus larvae to hypothermia or hyperthermia in relation to ecological temperature has resulted in alteration of enzyme activities related to maintenance of free amino acid pool and protein degradation. Sudden changes in water temperature have led to elevation of protein content particularly in molecular weight between 66 and 97.4 kDa. MALDI TOF analysis revealed the presence of putative uncharacterized protein and Phospholipase A2 activating protein in larvae subjected to 40°C for 1 hour which was not found in control and other temperature treated larvae. These proteins may be playing a role in survival of larvae at higher temperatures. Thermal shock has resulted in channeling of free amino acids for protein synthesis and elevation of amino acid catabolism through increased deamination and altered transamination, which resulted in a sharp decrease in free amino acid pool. Inhibition of Leucine amino peptidase and elevation of Cathepsin D, under the influence of thermal shock may be an adaptive response of larvae to prevent unnecessary degradation of protein and at the same time facilitated rapid internal re-organization which may accelerate pupation. Elevated activity of Phenol oxidase and its co-stimulator Trypsin -like Serine protease, along with increased expression of Phospholipase A2 activating protein is a well co-ordinated defense mechanism leading to increased immune response in stressed state. This study assumes significance because variation in environmental conditions such as global warming and their impact on mosquito physiology can influence efficiency of disease vector.


Assuntos
Adaptação Fisiológica , Aminoácidos/metabolismo , Culex/enzimologia , Larva/enzimologia , Estresse Fisiológico , Temperatura , Animais , Catepsina D/metabolismo , Resposta ao Choque Frio , Glutamato Desidrogenase/metabolismo , Resposta ao Choque Térmico , Proteínas de Insetos , Leucil Aminopeptidase/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Serina Endopeptidases/metabolismo , Transaminases/metabolismo
18.
Carcinogenesis ; 38(3): 252-260, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28426875

RESUMO

Emerging evidence from epidemiological studies suggests a link between environmental chemical exposure and progression of aggressive breast cancer subtypes. Of all clinically distinct types of breast cancers, the most lethal phenotypic variant is inflammatory breast cancer (IBC). Overexpression of epidermal growth factor receptors (EGFR/HER2) along with estrogen receptor (ER) negativity is common in IBC tumor cells, which instead of a solid mass present as rapidly proliferating diffuse tumor cell clusters. Our previous studies have demonstrated a role of an adaptive response of increased antioxidants in acquired resistance to EGFR-targeting drugs in IBC. Environmental chemicals are known to induce oxidative stress resulting in perturbations in signal transduction pathways. It is therefore of interest to identify chemicals that can potentiate EGFR mitogenic effects in IBC. Herein, we assessed in ER-negative IBC cells a subset of chemicals from the EPA ToxCast set for their effect on EGFR activation and in multiple cancer phenotypic assays. We demonstrated that endocrine-disrupting chemicals such as bisphenol A (BPA) and 2,2-bis(p-hydroxyphenyl)-1,1,1-trichloroethane can increase EGFR/ERK signaling. BPA also caused a corresponding increase in expression of SOD1 and anti-apoptotic Bcl-2, key markers of antioxidant and anti-apoptotic processes. BPA potentiated clonogenic growth and tumor spheroid formation in vitro, reflecting IBC-specific pathological characteristics. Furthermore, we identified that BPA was able to attenuate the inhibitory effect of an EGFR targeted drug in a longer-term anchorage-independent growth assay. These findings provide a potential mechanistic basis for environmental chemicals such as BPA in potentiating a hyperproliferative and death-resistant phenotype in cancer cells by activating mitogenic pathways to which the tumor cells are addicted for survival.


Assuntos
Compostos Benzidrílicos/toxicidade , Carcinógenos Ambientais/toxicidade , Receptores ErbB/genética , Neoplasias Inflamatórias Mamárias/tratamento farmacológico , Fenóis/toxicidade , Compostos Benzidrílicos/farmacologia , Carcinógenos Ambientais/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/antagonistas & inibidores , Receptor alfa de Estrogênio/genética , MAP Quinases Reguladas por Sinal Extracelular/genética , Feminino , Humanos , Neoplasias Inflamatórias Mamárias/genética , Neoplasias Inflamatórias Mamárias/patologia , Estresse Oxidativo/efeitos dos fármacos , Fenóis/farmacologia , Transdução de Sinais/efeitos dos fármacos , Esferoides Celulares/efeitos dos fármacos
20.
Int Ophthalmol ; 36(3): 413-7, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26499903

RESUMO

Nested polymerase chain reaction (nPCR) was performed on enucleated eyeball for detection of Mycobacterium tuberculosis (M. tb) genome in a patient with Eales' disease. PCR analysis in all previous studies has been done mainly using aqueous, vitreous and epiretinal membranes from these patients. Paraffin wax embedded tissue section of the enucleated eyeball was analyzed by histopathology and nPCR targeting MPB64 gene and IS6110 region of M. tb genome. Lymphocytic infiltration was seen in the vitreous, iris and the retinal tissue. Ziehl Neelsen stain was negative for acid fast bacilli. Caseation necrosis was not seen in any section. Agarose gel electrophoretogram showed positive results with 200 bp specific amplified product targeting MPB64 gene, whereas nPCR targeting IS6110 region was negative. Since biopsy proven M. tb is extremely difficult in ocular tissues due to extensive necrosis, the nPCR technique aided in the diagnosis.


Assuntos
Enucleação Ocular , Mycobacterium tuberculosis/genética , Neovascularização Patológica/complicações , Reação em Cadeia da Polimerase/métodos , Vasculite Retiniana/complicações , Tuberculose Ocular/microbiologia , DNA Bacteriano/análise , Humanos , Masculino , Tuberculose Ocular/diagnóstico , Adulto Jovem
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