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1.
J Pers Med ; 12(9)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36143293

RESUMO

Type 1 diabetes mellitus (T1DM) patients are a significant threat to chronic kidney disease (CKD) development during their life. However, there is always a high chance of delay in CKD detection because CKD can be asymptomatic, and T1DM patients bypass traditional CKD tests during their routine checkups. This study aims to develop and validate a prediction model and nomogram of CKD in T1DM patients using readily available routine checkup data for early CKD detection. This research utilized 1375 T1DM patients' sixteen years of longitudinal data from multi-center Epidemiology of Diabetes Interventions and Complications (EDIC) clinical trials conducted at 28 sites in the USA and Canada and considered 17 routinely available features. Three feature ranking algorithms, extreme gradient boosting (XGB), random forest (RF), and extremely randomized trees classifier (ERT), were applied to create three feature ranking lists, and logistic regression analyses were performed to develop CKD prediction models using these ranked feature lists to identify the best performing top-ranked features combination. Finally, the most significant features were selected to develop a multivariate logistic regression-based CKD prediction model for T1DM patients. This model was evaluated using sensitivity, specificity, accuracy, precision, and F1 score on train and test data. A nomogram of the final model was further generated for easy application in clinical practices. Hypertension, duration of diabetes, drinking habit, triglycerides, ACE inhibitors, low-density lipoprotein (LDL) cholesterol, age, and smoking habit were the top-8 features ranked by the XGB model and identified as the most important features for predicting CKD in T1DM patients. These eight features were selected to develop the final prediction model using multivariate logistic regression, which showed 90.04% and 88.59% accuracy in internal and test data validation. The proposed model showed excellent performance and can be used for CKD identification in T1DM patients during routine checkups.

2.
Anal Biochem ; 650: 114707, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35568159

RESUMO

Cancer is one of the most dangerous diseases in the world that often leads to misery and death. Current treatments include different kinds of anticancer therapy which exhibit different types of side effects. Because of certain physicochemical properties, anticancer peptides (ACPs) have opened a new path of treatments for this deadly disease. That is why a well-performed methodology for identifying novel anticancer peptides has great importance in the fight against cancer. In addition to the laboratory techniques, various machine learning and deep learning methodologies have developed in recent years for this task. Although these models have shown reasonable predictive ability, there's still room for improvement in terms of performance and exploring new types of algorithms. In this work, we have proposed a novel multi-channel convolutional neural network (CNN) for identifying anticancer peptides from protein sequences. We have collected data from the existing state-of-the-art methodologies and applied binary encoding for data preprocessing. We have also employed k-fold cross-validation to train our models on benchmark datasets and compared our models' performance on the independent datasets. The comparison has indicated our models' superiority on various evaluation metrics. We think our work can be a valuable asset in finding novel anticancer peptides. We have provided a user-friendly web server for academic purposes and it is publicly available at: http://103.99.176.239/iacp-cnn/.


Assuntos
Antineoplásicos , Neoplasias , Sequência de Aminoácidos , Antineoplásicos/química , Humanos , Neoplasias/tratamento farmacológico , Redes Neurais de Computação , Peptídeos/química
3.
IEEE/ACM Trans Comput Biol Bioinform ; 19(6): 3624-3634, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34546927

RESUMO

Identifying of post-translational modifications (PTM) is crucial in the study of computational proteomics, cell biology, pathogenesis, and drug development due to its role in many bio-molecular mechanisms. Computational methods for predicting multiple PTM at the same lysine residues, often referred to as K-PTM, is still evolving. This paper presents a novel computational tool, abbreviated as predML-Site, for predicting KPTM, such as acetylation, crotonylation, methylation, succinylation from an uncategorized peptide sample involving single, multiple, or no modification. For informative feature representation, multiple sequence encoding schemes, such as the sequence-coupling, binary encoding, k-spaced amino acid pairs, amino acid factor have been used with ANOVA and incremental feature selection. As a core predictor, a cost-sensitive SVM classifier has been adopted which effectively mitigates the effect of class-label imbalance in the dataset. predML-Site predicts multi-label PTM sites with 84.18% accuracy using the top 91 features. It has also achieved 85.34% aiming and 86.58% coverage rate which are much better than the existing state-of-the-art predictors on the same rigorous validation test. This performance indicates that predML-Site can be used as a supportive tool for further K-PTM study. For the convenience of the experimental scientists, predML-Site has been deployed as a user-friendly web-server at http://103.99.176.239/predML-Site.


Assuntos
Algoritmos , Lisina , Lisina/química , Biologia Computacional/métodos , Aminoácidos/química , Peptídeos
4.
Nat Immunol ; 22(1): 53-66, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33230330

RESUMO

Regenerative stem cell-like memory (TSCM) CD8+ T cells persist longer and produce stronger effector functions. We found that MEK1/2 inhibition (MEKi) induces TSCM that have naive phenotype with self-renewability, enhanced multipotency and proliferative capacity. This is achieved by delaying cell division and enhancing mitochondrial biogenesis and fatty acid oxidation, without affecting T cell receptor-mediated activation. DNA methylation profiling revealed that MEKi-induced TSCM cells exhibited plasticity and loci-specific profiles similar to bona fide TSCM isolated from healthy donors, with intermediate characteristics compared to naive and central memory T cells. Ex vivo, antigenic rechallenge of MEKi-treated CD8+ T cells showed stronger recall responses. This strategy generated T cells with higher efficacy for adoptive cell therapy. Moreover, MEKi treatment of tumor-bearing mice also showed strong immune-mediated antitumor effects. In conclusion, we show that MEKi leads to CD8+ T cell reprogramming into TSCM that acts as a reservoir for effector T cells with potent therapeutic characteristics.


Assuntos
Antineoplásicos/farmacologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Memória Imunológica/efeitos dos fármacos , Imunoterapia Adotiva , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Neoplasias/terapia , Células-Tronco/citologia , Animais , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Ciclo Celular/efeitos dos fármacos , Humanos , Memória Imunológica/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Receptores de Antígenos de Linfócitos T/fisiologia , Microambiente Tumoral
5.
Indian J Ophthalmol ; 68(12): 2935-2939, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33229673

RESUMO

PURPOSE: The purpose of this study was to evaluate wound healing abilities and efficacy of topical Vitamin C, Vitamin E, and acetylcysteine for their possible clinical use. METHODS: The study was conducted on 36 eyes of 18 single-breed rabbits, Oryctolagus cuniculus, of both sexes. A 7.5 mm calibrated vacuum corneal trephine was used to induce a defect of 100 micron depth in center of both the corneas. The right eye of rabbits was selected as the control eye and the left eye as the trial eye, which received eyedrops as Group 1-10% Vitamin C eyedrops, Group 2-3% acetylcysteine eye drops, and Group 3-1% Vitamin E eye drops. Control eyes received ringer lactate. Evaluation was done for fluorescein stain positivity, epithelial defect size, and corneal haze on Day 2, Day 7, and Day 14 post induction of the epithelial defect. RESULTS: On day 14, three eyes of control group, all Vitamin C and acetylcysteine treated eyes, and four Vitamin E treated eyes were fluorescein stain negative. The mean defect area on day 14 was 0, 0, 0.13, and 1.86 mm2 in Vitamin C, Vitamin E, acetylcysteine, and control eyes, respectively. Vitamin C and Vitamin E control corneal haze better than acetylcysteine in experimentally induced corneal wounds in rabbits. CONCLUSION: The three trial drugs with different mechanism of action showed similar effect on healing of the experimentally created corneal wounds in rabbits, with comparison showing statistical insignificance.


Assuntos
Acetilcisteína , Epitélio Corneano , Animais , Ácido Ascórbico , Córnea , Feminino , Masculino , Soluções Oftálmicas , Coelhos , Vitamina E , Cicatrização
6.
Med Hypotheses ; 142: 109754, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32438240

RESUMO

The recent global pandemic created by the Coronavirus SARS-CoV-2, started in Wuhan, China in December 2019, has generated panic, both in term of human death (4-5% of infected patients identified through testing) and the global economy. Human sufferings seem to be continuing, and it is not clear how long this will continue and how much more destruction it is going to cause until complete control is achieved. One of the most disturbing issues is Covid-19 treatment; although a large number of medications, previously used successfully with other viruses (including Chinese herbal medicines and anti-malaria drugs), are under consideration, there remain questions as to whether they can play a satisfactory role for this disease. Global attempts are ongoing to find the drugs for the treatment of this virus but none of the antiviral drugs used for treatment of other human viral infection is working and hence attempts to find new drugs are continuing. Here the author is proposing that 5-Fluorouracil (5-FU) which when used on its own is failing as an antiviral agent due to the removal of this compound by proof reading ability exceptionally found in Coronaviruses. The author here is proposing to test 5-FU in combination with a number of deoxynucleosides on animal models infected with this Covid-19. Should encouraging results ensue, therapies could then be tried on patients.


Assuntos
Infecções por Coronavirus/tratamento farmacológico , Desoxirribonucleosídeos/administração & dosagem , Desoxirribose/administração & dosagem , Fluoruracila/administração & dosagem , Pneumonia Viral/tratamento farmacológico , Monofosfato de Adenosina/administração & dosagem , Monofosfato de Adenosina/análogos & derivados , Alanina/administração & dosagem , Alanina/análogos & derivados , Betacoronavirus , COVID-19 , Cloroquina/administração & dosagem , Cloroquina/análogos & derivados , Ensaios Clínicos como Assunto , Esquema de Medicação , Sinergismo Farmacológico , Humanos , Inflamação/tratamento farmacológico , Modelos Teóricos , Pandemias , SARS-CoV-2 , Tratamento Farmacológico da COVID-19
7.
Nat Immunol ; 20(9): 1231-1243, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31358999

RESUMO

Understanding resistance to antibody to programmed cell death protein 1 (PD-1; anti-PD-1) is crucial for the development of reversal strategies. In anti-PD-1-resistant models, simultaneous anti-PD-1 and vaccine therapy reversed resistance, while PD-1 blockade before antigen priming abolished therapeutic outcomes. This was due to induction of dysfunctional PD-1+CD38hi CD8+ cells by PD-1 blockade in suboptimally primed CD8 cell conditions induced by tumors. This results in erroneous T cell receptor signaling and unresponsiveness to antigenic restimulation. On the other hand, PD-1 blockade of optimally primed CD8 cells prevented the induction of dysfunctional CD8 cells, reversing resistance. Depleting PD-1+CD38hi CD8+ cells enhanced therapeutic outcomes. Furthermore, non-responding patients showed more PD-1+CD38+CD8+ cells in tumor and blood than responders. In conclusion, the status of CD8+ T cell priming is a major contributor to anti-PD-1 therapeutic resistance. PD-1 blockade in unprimed or suboptimally primed CD8 cells induces resistance through the induction of PD-1+CD38hi CD8+ cells that is reversed by optimal priming. PD-1+CD38hi CD8+ cells serve as a predictive and therapeutic biomarker for anti-PD-1 treatment. Sequencing of anti-PD-1 and vaccine is crucial for successful therapy.


Assuntos
ADP-Ribosil Ciclase 1/metabolismo , Linfócitos T CD8-Positivos/imunologia , Resistencia a Medicamentos Antineoplásicos/imunologia , Glicoproteínas de Membrana/metabolismo , Neoplasias/imunologia , Receptor de Morte Celular Programada 1/imunologia , ADP-Ribosil Ciclase 1/genética , Animais , Anticorpos/imunologia , Linfócitos T CD8-Positivos/patologia , Vacinas Anticâncer/imunologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Imunoterapia/métodos , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Microambiente Tumoral/imunologia
8.
Cancer Immunol Res ; 6(2): 201-208, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29305519

RESUMO

Although an immune response to tumors may be generated using vaccines, so far, this approach has only shown minimal clinical success. This is attributed to the tendency of cancer to escape immune surveillance via multiple immune suppressive mechanisms. Successful cancer immunotherapy requires targeting these inhibitory mechanisms along with enhancement of antigen-specific immune responses to promote sustained tumor-specific immunity. Here, we evaluated the effect of indoximod, an inhibitor of the immunosuppressive indoleamine-(2,3)-dioxygenase (IDO) pathway, on antitumor efficacy of anti-OX40 agonist in the context of vaccine in the IDO- TC-1 tumor model. We demonstrate that although the addition of anti-OX40 to the vaccine moderately enhances therapeutic efficacy, incorporation of indoximod into this treatment leads to enhanced tumor regression and cure of established tumors in 60% of treated mice. We show that the mechanisms by which the IDO inhibitor leads to this therapeutic potency include (i) an increment of vaccine-induced tumor-infiltrating effector T cells that is facilitated by anti-OX40 and (ii) a decrease of IDO enzyme activity produced by nontumor cells within the tumor microenvironment that results in enhancement of the specificity and the functionality of vaccine-induced effector T cells. Our findings suggest a translatable strategy to enhance the overall efficacy of cancer immunotherapy. Cancer Immunol Res; 6(2); 201-8. ©2018 AACR.


Assuntos
Antígenos de Diferenciação/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Triptofano Oxigenase/antagonistas & inibidores , Triptofano/análogos & derivados , Animais , Antígenos de Diferenciação/imunologia , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/farmacologia , Epitopos de Linfócito T , Feminino , Humanos , Imunoterapia/métodos , Neoplasias Pulmonares/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Triptofano/farmacologia , Triptofano Oxigenase/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Adv Exp Med Biol ; 996: 3-11, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29124686

RESUMO

The use of ultraviolet (UV) light, for the treatment of skin conditions, dates back to the early 1900s. It is well known that sunlight can be of therapeutic value, but it can also lead to deleterious effects such as burning and carcinogenesis. Extensive research has expanded our understanding of UV radiation and its effects in human systems and has led to the development of man-made UV sources that are more precise, safer, and more effective for the treatment of wide variety of dermatologic conditions.


Assuntos
Lasers/história , Fotoquimioterapia/história , Dermatopatias/história , Raios Ultravioleta/história , Terapia Ultravioleta/história , Animais , Desenho de Equipamento , História do Século XIX , História do Século XX , História do Século XXI , Humanos , Lasers/efeitos adversos , Segurança do Paciente , Fotoquimioterapia/efeitos adversos , Fotoquimioterapia/instrumentação , Doses de Radiação , Exposição à Radiação/história , Fatores de Risco , Dermatopatias/tratamento farmacológico , Dermatopatias/radioterapia , Resultado do Tratamento , Raios Ultravioleta/efeitos adversos , Terapia Ultravioleta/efeitos adversos , Terapia Ultravioleta/instrumentação
10.
J Immunother Cancer ; 5(1): 64, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28807056

RESUMO

BACKGROUND: We previously demonstrated that in addition to generating an antigen-specific immune response, Listeria monocytogenes (Lm)-based immunotherapy significantly reduces the ratio of regulatory T cells (Tregs)/CD4+ and myeloid-derived suppressor cells (MDSCs) in the tumor microenvironment. Since Lm-based immunotherapy is able to inhibit the immune suppressive environment, we hypothesized that combining this treatment with agonist antibody to a co-stimulatory receptor that would further boost the effector arm of immunity will result in significant improvement of anti-tumor efficacy of treatment. METHODS: Here we tested the immune and therapeutic efficacy of Listeria-based immunotherapy combination with agonist antibody to glucocorticoid-induced tumor necrosis factor receptor-related protein (GITR) in TC-1 mouse tumor model. We evaluated the potency of combination on tumor growth and survival of treated animals and profiled tumor microenvironment for effector and suppressor cell populations. RESULTS: We demonstrate that combination of Listeria-based immunotherapy with agonist antibody to GITR synergizes to improve immune and therapeutic efficacy of treatment in a mouse tumor model. We show that this combinational treatment leads to significant inhibition of tumor-growth, prolongs survival and leads to complete regression of established tumors in 60% of treated animals. We determined that this therapeutic benefit of combinational treatment is due to a significant increase in tumor infiltrating effector CD4+ and CD8+ T cells along with a decrease of inhibitory cells. CONCLUSION: To our knowledge, this is the first study that exploits Lm-based immunotherapy combined with agonist anti-GITR antibody as a potent treatment strategy that simultaneously targets both the effector and suppressor arms of the immune system, leading to significantly improved anti-tumor efficacy. We believe that our findings depicted in this manuscript provide a promising and translatable strategy that can enhance the overall efficacy of cancer immunotherapy.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Proteína Relacionada a TNFR Induzida por Glucocorticoide/agonistas , Imunoterapia/métodos , Listeria monocytogenes/imunologia , Neoplasias Pulmonares/terapia , Células Supressoras Mieloides/efeitos dos fármacos , Animais , Anticorpos Monoclonais/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linhagem Celular Tumoral , Terapia Combinada , Humanos , Neoplasias Pulmonares/imunologia , Camundongos , Linfócitos T Reguladores/efeitos dos fármacos , Resultado do Tratamento , Microambiente Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Cancer Immunol Res ; 5(9): 755-766, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28848055

RESUMO

Combination therapies that depend on checkpoint inhibitor antibodies (Abs) such as for PD-1 or its ligand (PD-L1) together with immune stimulatory agonist Abs like anti-OX40 are being tested in the clinic to achieve improved antitumor effects. Here, we studied the potential therapeutic and immune effects of one such combination: Ab to PD-1 with agonist Ab to OX40/vaccine. We tested the antitumor effects of different treatment sequencing of this combination. We report that simultaneous addition of anti-PD-1 to anti-OX40 negated the antitumor effects of OX40 Ab. Antigen-specific CD8+ T-cell infiltration into the tumor was diminished, the resultant antitumor response weakened, and survival reduced. Although we observed an increase in IFNγ-producing E7-specifc CD8+ T cells in the spleens of mice treated with the combination of PD-1 blockade with anti-OX40/vaccine, these cells underwent apoptosis both in the periphery and the tumor. These results indicate that anti-PD-1 added at the initiation of therapy exhibits a detrimental effect on the positive outcome of anti-OX40 agonist Ab. These findings have important implications on the design of combination immunotherapy for cancer, demonstrating the need to test treatment combination and sequencing before moving to the clinic. Cancer Immunol Res; 5(9); 755-66. ©2017 AACR.


Assuntos
Antígenos de Diferenciação/imunologia , Antígeno B7-H1/imunologia , Imunoterapia , Neoplasias Pulmonares/imunologia , Receptor de Morte Celular Programada 1/imunologia , Animais , Anticorpos/administração & dosagem , Anticorpos/imunologia , Apoptose/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/imunologia , Linhagem Celular Tumoral , Terapia Combinada , Modelos Animais de Doenças , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Camundongos , Receptor de Morte Celular Programada 1/antagonistas & inibidores
12.
Cancer Res ; 77(15): 4135-4145, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28615225

RESUMO

Inhibition of specific Akt isoforms in CD8+ T cells promotes favored differentiation into memory versus effector cells, the former of which are superior in mediating antitumor immunity. In this study, we investigated the role of upstream PI3K isoforms in CD8+ T-cell differentiation and assessed the potential use of PI3K isoform-specific inhibitors to favorably condition CD8+ T cells for adoptive cell therapy. The phenotype and proliferative ability of tumor antigen-specific CD8+ T cells was assessed in the presence of PI3K-α, -ß, or -δ inhibitors. Inhibition of PI3K-δ, but not PI3K-α or PI3K-ß, delayed terminal differentiation of CD8+ T cells and maintained the memory phenotype, thus enhancing their proliferative ability and survival while maintaining their cytokine and granzyme B production ability. This effect was preserved in vivo after ex vivo PI3K-δ inhibition in CD8+ T cells destined for adoptive transfer, enhancing their survival and also the antitumor therapeutic activity of a tumor-specific peptide vaccine. Our results outline a mechanism by which inhibitions of a single PI3K isoform can enhance the proliferative potential, function, and survival of CD8+ T cells, with potential clinical implications for adoptive cell transfer and vaccine-based immunotherapies. Cancer Res; 77(15); 4135-45. ©2017 AACR.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Imunoterapia Adotiva/métodos , Melanoma Experimental/patologia , Inibidores de Fosfoinositídeo-3 Quinase , Animais , Linfócitos T CD8-Positivos/enzimologia , Diferenciação Celular/efeitos dos fármacos , Classe I de Fosfatidilinositol 3-Quinases , Inibidores Enzimáticos/farmacologia , Feminino , Memória Imunológica/imunologia , Ativação Linfocitária/imunologia , Melanoma Experimental/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
13.
Cancer Res ; 77(8): 1892-1904, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28108509

RESUMO

To modulate T-cell function for cancer therapy, one challenge is to selectively attenuate regulatory but not conventional CD4+ T-cell subsets [regulatory T cell (Treg) and conventional T cell (Tconv)]. In this study, we show how a functional dichotomy in Class IA PI3K isoforms in these two subsets of CD4+ T cells can be exploited to target Treg while leaving Tconv intact. Studies employing isoform-specific PI3K inhibitors and a PI3Kδ-deficient mouse strain revealed that PI3Kα and PI3Kß were functionally redundant with PI3Kδ in Tconv. Conversely, PI3Kδ was functionally critical in Treg, acting there to control T-cell receptor signaling, cell proliferation, and survival. Notably, in a murine model of lung cancer, coadministration of a PI3Kδ-specific inhibitor with a tumor-specific vaccine decreased numbers of suppressive Treg and increased numbers of vaccine-induced CD8 T cells within the tumor microenvironment, eliciting potent antitumor efficacy. Overall, our results offer a mechanistic rationale to employ PI3Kδ inhibitors to selectively target Treg and improve cancer immunotherapy. Cancer Res; 77(8); 1892-904. ©2017 AACR.


Assuntos
Linfócitos T CD4-Positivos/enzimologia , Linfócitos T CD4-Positivos/imunologia , Neoplasias Experimentais/terapia , Fosfatidilinositol 3-Quinases/imunologia , Linfócitos T Reguladores/enzimologia , Linfócitos T Reguladores/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/farmacologia , Sinergismo Farmacológico , Inibidores Enzimáticos/farmacologia , Feminino , Imunoterapia/métodos , Isoenzimas , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias Experimentais/enzimologia , Neoplasias Experimentais/imunologia , Fosfatidilinositol 3-Quinases/genética , Inibidores de Fosfoinositídeo-3 Quinase , Purinas/farmacologia , Quinazolinonas/farmacologia , Transdução de Sinais/imunologia , Subpopulações de Linfócitos T/imunologia
14.
J Virol ; 91(5)2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28031367

RESUMO

The human genome displays a rich fossil record of past gammaretrovirus infections, yet no current epidemic is evident, despite environmental exposure to viruses that infect human cells in vitro Feline leukemia viruses (FeLVs) rank high on this list, but neither domestic nor workplace exposure has been associated with detectable serological responses. Nonspecific inactivation of gammaretroviruses by serum factors appears insufficient to explain these observations. To investigate further, we explored the susceptibilities of primary and established human cell lines to FeLV-B, the most likely zoonotic variant. Fully permissive infection was common in cancer-derived cell lines but was also a feature of nontransformed keratinocytes and lung fibroblasts. Cells of hematopoietic origin were generally less permissive and formed discrete groups on the basis of high or low intracellular protein expression and virion release. Potent repression was observed in primary human blood mononuclear cells and a subset of leukemia cell lines. However, the early steps of reverse transcription and integration appear to be unimpaired in nonpermissive cells. FeLV-B was subject to G→A hypermutation with a predominant APOBEC3G signature in partially permissive cells but was not mutated in permissive cells or in nonpermissive cells that block secondary viral spread. Distinct cellular barriers that protect primary human blood cells are likely to be important in protection against zoonotic infection with FeLV.IMPORTANCE Domestic exposure to gammaretroviruses such as feline leukemia viruses (FeLVs) occurs worldwide, but the basis of human resistance to infection remains incompletely understood. The potential threat is evident from the human genome sequence, which reveals many past epidemics of gammaretrovirus infection, and from recent cross-species jumps of gammaretroviruses from rodents to primates and marsupials. This study examined resistance to infection at the cellular level with the most prevalent human cell-tropic FeLV variant, FeLV-B. We found that blood cells are uniquely resistant to infection with FeLV-B due to the activity of cellular enzymes that mutate the viral genome. A second block, which appears to suppress viral gene expression after the viral genome has integrated into the host cell genome, was identified. Since cells derived from other normal human cell types are fully supportive of FeLV replication, innate resistance of blood cells could be critical in protecting against cross-species infection.


Assuntos
Vírus da Leucemia Felina/fisiologia , Infecções por Retroviridae/virologia , Desaminase APOBEC-3G/genética , Desaminase APOBEC-3G/metabolismo , Animais , Gatos , Linhagem Celular Tumoral , Suscetibilidade a Doenças , Expressão Gênica , Genoma Viral , Células HEK293 , Humanos , Mutação , Especificidade da Espécie , Tropismo Viral , Integração Viral , Replicação Viral , Zoonoses/virologia
15.
Indian J Med Res ; 143(Supplement): S68-S73, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27748280

RESUMO

BACKGROUND & OBJECTIVES: There is lack of data on natural history and progression of prostate cancer (PC) which have implications in the management of the disease. We undertook this retrospective study to analyze factors predicting progression of metastatic PC to castration-resistant prostate cancer (CRPC) in Indian men. METHODS: Complete records of 223 of the 489 patients with metastatic PC were obtained from computerized data based system in a tertiary care hospital in north India between January 2000 to June 2012. Patients with follow up of < 6 months were excluded. Age (≤ and > 65 yr), baseline PSA (< and ≥ 50 ng/ml), bone scan and Gleason score (≤7 and >7) were recorded. Extent of bone disease (EOD) was stratified according to the number of bone lesions i.e., < 5, 5-10, > 10. CRPC was defined as two consecutive PSA rise of > 50 per cent from nadir or an absolute value of > 5 ng/ml. RESULTS: Mean age of patients was 61.5 ± 12.45 yr and their PSA level was 325.6 ± 631.35 ng/dl. Of the 223 patients, 193 (86%) progressed to CRPC at median time of 10.7 (4-124) months. Median follow up was 24 (6-137) months. On univariate and multivariate analyses EOD on bone scan was found to be a significant predictor ( P=0.006) for time to CRPC. Median time to CRPC was 10 months (CI 95%, 7.5-12.48) with >10 lesions or super scan versus 16 months (CI 95%, 10.3-21.6) with <10 bone lesion (P=0.01). Ninety (46.6 %) patients of CRPC died with median time to death from time of CRPC 21 (10-120) months. INTERPRETATION & CONCLUSIONS: Median time for progression of metastatic PC to CRPC ranged from 10-16 months depending on the extent of the bone involvement. In Indians, the aggressive course of advanced prostate cancer warrants further clinical trials to explore the need for additional treatment along with initial castration.


Assuntos
Neoplasias Ósseas/patologia , Metástase Neoplásica , Antígeno Prostático Específico/sangue , Neoplasias de Próstata Resistentes à Castração/patologia , Adulto , Idoso , Neoplasias Ósseas/sangue , Neoplasias Ósseas/secundário , Progressão da Doença , Seguimentos , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Gradação de Tumores , Neoplasias de Próstata Resistentes à Castração/sangue , Fatores de Tempo
16.
Oncoimmunology ; 5(4): e1115941, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27141399

RESUMO

The tumor microenvironment (TME) contains high levels of the Wnt family of ligands, and aberrant Wnt-signaling occurs in many tumors. Past studies have been directed toward how the Wnt signaling cascade regulates cancer development, progression and metastasis. However, its effects on host antitumor immunity remain unknown. In this report, we show that Wnts in the TME condition dendritic cells (DCs) to a regulatory state and suppress host antitumor immunity. DC-specific deletion of Wnt co-receptors low-density lipoprotein receptor-related protein 5 and 6 (LRP5/6) in mice markedly delayed tumor growth and enhanced host antitumor immunity. Mechanistically, loss of LRP5/6-mediated signaling in DCs resulted in enhanced effector T cell differentiation and decreased regulatory T cell differentiation. This was due to increased production of pro-inflammatory cytokines and decreased production of IL-10, TGF-ß1 and retinoic acid (RA). Likewise, pharmacological inhibition of the Wnts' interaction with its cognate co-receptors LRP5/6 and Frizzled (Fzd) receptors had similar effects on tumor growth and effector T cell responses. Moreover, blocking Wnt-signaling in DCs resulted in enhanced capture of tumor-associated antigens and efficient cross-priming of CD8+ T cells. Hence, blocking the Wnt pathway represents a potential therapeutic to overcome tumor-mediated immune suppression and augment antitumor immunity.

17.
Indian J Urol ; 30(1): 28-32, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24497678

RESUMO

INTRODUCTION: Free to total prostate specific antigen ratio (f/t PSA) has been used to help improving specificity of PSA in the range of 4-10 ng/ml based on the data on population based screening. There is no data on test characteristics of f/t PSA in men presenting with clinical symptoms of benign prostatic hyperplasia (BPH). This study is aimed to determine the usefulness of f/t PSA in symptomatic men. METHODOLOGY: From January 2006 to June 2012, men of 50-75 years with lower urinary tract symptoms (LUTS), normal rectal examination and PSA between 4-20 ng/ml had free and total PSA assessment. Men with clinical evidence of prostatitis, retention, history of 5α blocker reductase inhibitors and those who had surgery or biopsy on the prostate in last 3 months were excluded. Receiver operating characteristic curves were derived for f/t PSA and total PSA. The effect of age, prostate volume and Gleason score on the f/t PSA was also analyzed. All statistical analyses were performed on SPSS 16 (Chicago, USA). RESULTS: Out of 170 men with the mean age of 67.4 ± 6.6 years, 43 (25.3%) had cancer on biopsy. Area under the curve for predicting the presence or absence of prostate cancer in all the men with f/t ratio was 0.63 (confidence interval [CI]: 0.54-0.71). The median value of f/t PSA for men with cancer was 5.5% (1-25%) and 9.2% (1-63%) for those with no cancer. Cut-offs derived at 95% specificity at PSA between 4-10 ng/ml and 4-20 ng/ml were 0.5% and 1% respectively. The specificity of f/t PSA ratio at cut-off levels 7%, 10% and 15% was 73%, 60%, 45% for PSA range of 4-10 ng/ml and 63%, 47% and 35% for PSA range of 4-20 ng/ml PSA. Age, prostate volume and Gleason grade did not show any effect on f/t PSA. CONCLUSION: In men with LUTS the specificity of various f/t PSA ratio cut-offs; described for population based screening, is too low to be used as an aid to defer the decision of biopsy in PSA ranges of 4-20 ng/ml.

18.
J Nat Med ; 68(2): 274-83, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23645071

RESUMO

Cedrus deodara and Pinus roxburghii, plants mentioned in Indian literature, have been described to possess central nervous system effects and are used in Ayurvedic medicine to treat disorders of the mind. To investigate the memory-enhancing activity of volatile oil and chloroform extracts of C. deodara and P. roxburghii in the Morris water maze paradigm as well as evaluating their antioxidant properties. Aged albino mice were used to study the effect of oil and chloroform extracts on learning and memory by using the Morris water maze paradigm. The chloroform extract of C. deodara produced a significant decrease in escape latency over 7 days of training in both reference and working memory training in comparison to the control group. In the probe trial on day 8, mice in the chloroform extract of C. deodara group crossed the target area more often and spent more time in the target quadrant. Amongst the oils and extracts tested for oxidative stress parameters, only the chloroform extract of C. deodara at doses of 100 mg/kg produced a significant decrease in malondialdehyde (MDA) with a simultaneous significant increase in the level of glutathione (GSH) in both the frontal cortex and hippocampus. The present findings indicate that the chloroform extract of C. deodara has the best memory-enhancing effect due to its strong antioxidant properties from compounds like terpenoids and flavonoids. The study provides a scientific rationale for the traditional use of C. deodara in the management of memory dysfunction and related disorders.


Assuntos
Antioxidantes/farmacologia , Cedrus/química , Cognição/efeitos dos fármacos , Pinus/química , Envelhecimento , Animais , Encéfalo/efeitos dos fármacos , Glutationa/análise , Malondialdeído/análise , Memória/efeitos dos fármacos , Camundongos , Óleos Voláteis/farmacologia , Estresse Oxidativo , Extratos Vegetais/farmacologia
19.
Braz. j. microbiol ; 44(3): 799-806, July-Sept. 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-699813

RESUMO

This study reports the occurrence of antibiotic resistance and production of β-lactamases including extended spectrum beta-lactamases (ESβL) in enteric bacteria isolated from hospital wastewater. Among sixty-nine isolates, tested for antibiotic sensitivity, 73.9% strains were resistant to ampicillin followed by nalidixic acid (72.5%), penicillin (63.8%), co-trimoxazole (55.1%), norfloxacin (53.6%), methicillin (52.7%), cefuroxime (39.1%), cefotaxime (23.2%) and cefixime (20.3%). Resistance to streptomycin, chloramphenicol, nitrofurantoin, tetracycline, and doxycycline was recorded in less than 13% of the strains. The minimum inhibitory concentration (MIC) showed a high level of resistance (800-1600 µg/mL) to one or more antibiotics. Sixty three (91%) isolates produced β-lactamases as determined by rapid iodometric test. Multiple antibiotic resistances were noted in both among ESβL and non-ESβL producers. The β-lactamases hydrolyzed multiple substrates including penicillin (78.8% isolates), ampicillin (62.3%), cefodroxil (52.2%), cefotoxime (21.7%) and cefuroxime (18.8%). Fifteen isolates producing ESβLs were found multidrug resistant. Four ESβL producing isolates could transfer their R-plasmid to the recipient strain E. coli K-12 with conjugation frequency ranging from 7.0 x 10-3 to 8.8 x 10-4. The findings indicated that ESβL producing enteric bacteria are common in the waste water. Such isolates may disseminate the multiple antibiotic resistance traits among bacterial community through genetic exchange mechanisms and thus requires immediate attention.


Assuntos
Humanos , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Transferência Genética Horizontal , Águas Residuárias/microbiologia , Conjugação Genética , Enterobacteriaceae/efeitos dos fármacos , /genética , Hospitais , Incidência , Testes de Sensibilidade Microbiana , Fatores R , beta-Lactamases/metabolismo
20.
J Virol ; 87(19): 10874-83, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23903838

RESUMO

Feline leukemia virus (FeLV) is a naturally transmitted gammaretrovirus that infects domestic cats. FeLV-945, the predominant isolate associated with non-T-cell disease in a natural cohort, is a member of FeLV subgroup A but differs in sequence from the FeLV-A prototype, FeLV-A/61E, in the surface glycoprotein (SU) and long terminal repeat (LTR). Substitution of the FeLV-945 LTR into FeLV-A/61E resulted in pathogenesis indistinguishable from that of FeLV-A/61E, namely, thymic lymphoma of T-cell origin. In contrast, substitution of both FeLV-945 LTR and SU into FeLV-A/61E resulted in multicentric lymphoma of non-T-cell origin. These results implicated the FeLV-945 SU as a determinant of pathogenic spectrum. The present study was undertaken to test the hypothesis that FeLV-945 SU can act in the absence of other unique sequence elements of FeLV-945 to determine the disease spectrum. Substitution of FeLV-A/61E SU with that of FeLV-945 altered the clinical presentation and resulted in tumors that demonstrated expression of CD45R in the presence or absence of CD3. Despite the evident expression of CD45R, a typical B-cell marker, T-cell receptor beta (TCRß) gene rearrangement indicated a T-cell origin. Tumor cells were detectable in bone marrow and blood at earlier times during the disease process, and the predominant SU genes from proviruses integrated in tumor DNA carried markers of genetic recombination. The findings demonstrate that FeLV-945 SU alters pathogenesis, although incompletely, in the absence of FeLV-945 LTR. Evidence demonstrates that FeLV-945 SU and LTR are required together to fully recapitulate the distinctive non-T-cell disease outcome seen in the natural cohort.


Assuntos
Vírus da Leucemia Felina/patogenicidade , Linfoma/patologia , Glicoproteínas de Membrana/metabolismo , Infecções por Retroviridae/virologia , Sequências Repetidas Terminais/genética , Neoplasias do Timo/patologia , Infecções Tumorais por Vírus/virologia , Sequência de Aminoácidos , Animais , Southern Blotting , Gatos , DNA Viral/genética , Progressão da Doença , Feminino , Técnicas Imunoenzimáticas , Vírus da Leucemia Felina/fisiologia , Linfoma/genética , Linfoma/virologia , Glicoproteínas de Membrana/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Infecções por Retroviridae/metabolismo , Infecções por Retroviridae/patologia , Homologia de Sequência de Aminoácidos , Taxa de Sobrevida , Neoplasias do Timo/genética , Neoplasias do Timo/virologia , Infecções Tumorais por Vírus/metabolismo , Infecções Tumorais por Vírus/patologia , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo
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