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1.
Nature ; 583(7818): 807-812, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32669708

RESUMO

The majority of targeted therapies for non-small-cell lung cancer (NSCLC) are directed against oncogenic drivers that are more prevalent in patients with light exposure to tobacco smoke1-3. As this group represents around 20% of all patients with lung cancer, the discovery of stratified medicine options for tobacco-associated NSCLC is a high priority. Umbrella trials seek to streamline the investigation of genotype-based treatments by screening tumours for multiple genomic alterations and triaging patients to one of several genotype-matched therapeutic agents. Here we report the current outcomes of 19 drug-biomarker cohorts from the ongoing National Lung Matrix Trial, the largest umbrella trial in NSCLC. We use next-generation sequencing to match patients to appropriate targeted therapies on the basis of their tumour genotype. The Bayesian trial design enables outcome data from open cohorts that are still recruiting to be reported alongside data from closed cohorts. Of the 5,467 patients that were screened, 2,007 were molecularly eligible for entry into the trial, and 302 entered the trial to receive genotype-matched therapy-including 14 that re-registered to the trial for a sequential trial drug. Despite pre-clinical data supporting the drug-biomarker combinations, current evidence shows that a limited number of combinations demonstrate clinically relevant benefits, which remain concentrated in patients with lung cancers that are associated with minimal exposure to tobacco smoke.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/terapia , Marcadores Genéticos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Terapia de Alvo Molecular , Medicina de Precisão , Fumar/genética , Teorema de Bayes , Carcinoma Pulmonar de Células não Pequenas/etiologia , Protocolos Clínicos , Ensaios Clínicos como Assunto , Estudos de Coortes , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias Pulmonares/etiologia , Oncogenes/genética , Seleção de Pacientes , Fumaça/efeitos adversos , Triagem
3.
PLoS Pathog ; 19(10): e1011717, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37878666

RESUMO

A protective HIV-1 vaccine has been hampered by a limited understanding of how B cells acquire neutralizing activity. Our previous vaccines expressing two different HIV-1 envelopes elicited robust antigen specific serum IgG titers in 20 rhesus macaques; yet serum from only two animals neutralized the autologous virus. Here, we used high throughput immunoglobulin receptor and single cell RNA sequencing to characterize the overall expansion, recall, and maturation of antigen specific B cells longitudinally over 90 weeks. Diversification and expansion of many B cell clonotypes occurred broadly in the absence of serum neutralization. However, in one animal that developed neutralization, two neutralizing B cell clonotypes arose from the same immunoglobulin germline and were tracked longitudinally. Early antibody variants with high identity to germline neutralized the autologous virus while later variants acquired somatic hypermutation and increased neutralization potency. The early engagement of precursors capable of neutralization with little to no SHM followed by prolonged affinity maturation allowed the two neutralizing lineages to successfully persist despite many other antigen specific B cells. The findings provide new insight into B cells responding to HIV-1 envelope during heterologous prime and boost immunization in rhesus macaques and the development of selected autologous neutralizing antibody lineages.


Assuntos
Vacinas contra a AIDS , Infecções por HIV , Soropositividade para HIV , HIV-1 , Animais , Anticorpos Neutralizantes , Macaca mulatta , Anticorpos Anti-HIV , Imunização , Produtos do Gene env do Vírus da Imunodeficiência Humana
4.
Int J Mol Sci ; 24(17)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37685922

RESUMO

HTLV-1 is an oncogenic human retrovirus and the etiologic agent of the highly aggressive ATL malignancy. Two viral genes, Tax and Hbz, are individually linked to oncogenic transformation and play an important role in the pathogenic process. Consequently, regulation of HTLV-1 gene expression is a central feature in the viral lifecycle and directly contributes to its pathogenic potential. Herein, we identified the cellular transcription factor YBX1 as a binding partner for HBZ. We found YBX1 activated transcription and enhanced Tax-mediated transcription from the viral 5' LTR promoter. Interestingly, YBX1 also interacted with Tax. shRNA-mediated loss of YBX1 decreased transcript and protein abundance of both Tax and HBZ in HTLV-1-transformed T-cell lines, as well as Tax association with the 5' LTR. Conversely, YBX1 transcriptional activation of the 5' LTR promoter was increased in the absence of HBZ. YBX1 was found to be associated with both the 5' and 3' LTRs in HTLV-1-transformed and ATL-derived T-cell lines. Together, these data suggest that YBX1 positively influences transcription from both the 5' and 3' promoter elements. YBX1 is able to interact with Tax and help recruit Tax to the 5' LTR. However, through interactions with HBZ, YBX1 transcriptional activation of the 5' LTR is repressed.


Assuntos
Vírus Linfotrópico T Tipo 1 Humano , Proteína 1 de Ligação a Y-Box , Humanos , Genes Virais , Vírus Linfotrópico T Tipo 1 Humano/genética , Regiões Promotoras Genéticas , RNA Interferente Pequeno , Sequências Repetidas Terminais/genética , Proteína 1 de Ligação a Y-Box/genética
5.
J Infect Dis ; 225(9): 1632-1641, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-34331451

RESUMO

BACKGROUND: Diagnosis of paucibacillary tuberculosis (TB) including extrapulmonary TB is a significant challenge, particularly in high-income, low-incidence settings. Measurement of Mycobacterium tuberculosis (Mtb)-specific cellular immune signatures by flow cytometry discriminates active TB from latent TB infection (LTBI) in case-control studies; however, their diagnostic accuracy and clinical utility in routine clinical practice is unknown. METHODS: Using a nested case-control study design within a prospective multicenter cohort of patients presenting with suspected TB in England, we assessed diagnostic accuracy of signatures in 134 patients who tested interferon-gamma release assay (IGRA)-positive and had final diagnoses of TB or non-TB diseases with coincident LTBI. Cellular signatures were measured using flow cytometry. RESULTS: All signatures performed less well than previously reported. Only signatures incorporating measurement of phenotypic markers on functional Mtb-specific CD4 T cells discriminated active TB from non-TB diseases with LTBI. The signatures measuring HLA-DR+IFNγ + CD4 T cells and CD45RA-CCR7-CD127- IFNγ -IL-2-TNFα + CD4 T cells performed best with 95% positive predictive value (95% confidence interval, 90-97) in the clinically challenging subpopulation of IGRA-positive but acid-fast bacillus (AFB) smear-negative TB suspects. CONCLUSIONS: Two cellular immune signatures could improve and accelerate diagnosis in the challenging group of patients who are IGRA-positive, AFB smear-negative, and have paucibacillary TB.


Assuntos
Tuberculose Latente , Mycobacterium tuberculosis , Tuberculose , Estudos de Casos e Controles , Humanos , Testes de Liberação de Interferon-gama , Tuberculose Latente/diagnóstico , Estudos Prospectivos , Tuberculose/diagnóstico
6.
Scand J Immunol ; 96(5)2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37406035

RESUMO

CpG Oligodeoxynucleotides (ODNs) are established TLR9 ligands; however, their functional responses in CD4+ T cells are believed to be independent of TLR9 and MyD88. We studied ligand-receptor interactions of ODN 2216 and TLR9 in human CD4+ T cells and assessed their consequences in terms of TLR9 signalling and cell phenotype. We demonstrated that the uptake of ODN 2216, a synthetic TLR9 agonist, is controlled by TLR9 signalling molecules and results in an increase in the expression of TLR9 signalling molecules, regulated via a feedback mechanism. Next, the uptake of ODN 2216 resulted in TLR9 signalling dependent but MyD88 independent increase in expression of TGF-ß. Finally, ODN 2216 treated CD4+ T cells showed an anti-inflammatory phenotype that was similar to Th3 type of regulatory T cells. These Th3-like cells were able to suppress the proliferation of untreated CD4+ T cells. Collectively, our results demonstrate a direct and interdependent relationship between ODN 2216 uptake and TLR9 signalling in CD4+ T cells. Our findings thus pave the way for future research to explore direct modulation of adaptive immune cells, using innate immune ligands, to subvert exaggerated inflammatory responses.


Assuntos
Fator 88 de Diferenciação Mieloide , Receptor Toll-Like 9 , Humanos , Receptor Toll-Like 9/genética , Ligantes , Fator 88 de Diferenciação Mieloide/metabolismo , Linfócitos T CD4-Positivos , Transdução de Sinais , Oligodesoxirribonucleotídeos/farmacologia , Oligodesoxirribonucleotídeos/genética
7.
Haematologica ; 107(12): 2928-2943, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-35615924

RESUMO

Adult T-cell leukemia and lymphoma (ATLL) is an intractable T-cell neoplasia caused by a retrovirus, namely human T-cell leukemia virus type 1 (HTLV-1). Patients suffering from ATLL present a poor prognosis and have a dearth of treatment options. In contrast to the sporadic expression of viral transactivator protein Tax present at the 5' promoter region long terminal repeats (LTR), HTLV-1 bZIP gene (HBZ) is encoded by 3'LTR (the antisense promoter) and maintains its constant expression in ATLL cells and patients. The antisense promoter is associated with selective retroviral gene expression and has been an understudied phenomenon. Herein, we delineate the activity of transcription factor MEF (myocyte enhancer factor)-2 family members, which were found to be enriched at the 3'LTR and play an important role in the pathogenesis of ATLL. Of the four MEF isoforms (A to D), MEF-2A and 2C were highly overexpressed in a wide array of ATLL cell lines and in acute ATLL patients. The activity of MEF-2 isoforms were determined by knockdown experiments that led to decreased cell proliferation and regulated cell cycle progression. High enrichment of MEF-2C was observed at the 3'LTR along with cofactors Menin and JunD resulting in binding of MEF-2C to HBZ at this region. Chemical inhibition of MEF-2 proteins resulted in the cytotoxicity of ATLL cells in vitro and reduction of proviral load in a humanized mouse model. Taken together, this study provides a novel mechanism of 3'LTR regulation and establishes MEF-2 signaling a potential target for therapeutic intervention for ATLL.


Assuntos
Vírus Linfotrópico T Tipo 1 Humano , Leucemia-Linfoma de Células T do Adulto , Linfoma , Animais , Humanos , Camundongos , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/metabolismo , Leucemia-Linfoma de Células T do Adulto/patologia , Linfoma/genética , Fatores de Transcrição MEF2/genética , Fatores de Transcrição MEF2/metabolismo , Regiões Promotoras Genéticas , Proteínas Virais/genética , Proteínas Virais/metabolismo
8.
J Org Chem ; 87(19): 12547-12557, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-35584056

RESUMO

A thorough DFT study was performed to unravel the true mechanism involved in the Pd(0)-catalyzed functional group transposition between aroyl chlorides and aryl iodides. Two different experimental groups proposed different mechanisms for the functional group transposition reaction. A careful assessment of experimental findings and thorough computational studies endorsed that the functional group transposition proceeds via phosphonium salt formation and ligand-enabled C-P bond metathesis, leading to the formation of the PhI and the intermediate 2. After the formation of the intermediate 2, the transposition of functional groups takes place through the interpalladium ligand exchange mechanism, where two palladium centers act as shuttle catalysts. In short, both C-P bond metathesis and interpalladium ligand exchange steps are crucial in the functional group transposition mechanism.

9.
Saudi Pharm J ; 30(7): 879-905, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35645588

RESUMO

The SARS-CoV-2 (COVID 19) paroxysm is a dominant health exigency that caused significant distress, affecting physical and mental health. Increased mortality, a stressed healthcare system, financial crisis, isolation, and new living and working styles enhanced societal commiseration leading to poor health outcomes. Though people try to maintain good physical health but unfortunately the mental affliction is still ignored. Poor psychological health has emerged as a burgeoning social issue and demands attention. Henceforth, the fundamental objective of this review article is to collate information about COVID-linked physical and psychological agony in diverse population groups with related symptoms and accessible diagnosis techniques. Recent studies have unraveled the fragile mental states of people who have either contracted COVID 19 or had near and dear ones falling prey to it. The impact of the epidemic on the human mind both in short and long-term, with possible risk and preventive factors together with suggested solutions for maintaining good health have also been discussed here. It also enlists the available medications, vaccines and investigational research in the form of patents and clinical trials. This article can be taken as an updated information sheet for COVID 19, accompanied by its management techniques with special emphasis on coping strategies for mental health. Further, it may also assist the policymakers to devise approaches that could enable the public to overcome the pandemic-driven adversity not only in the given situation but also futuristically.

10.
Eur J Neurosci ; 53(2): 637-648, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33169893

RESUMO

One of the key knowledge gaps in the field of Alzheimer's disease research is the lack of understanding of how amyloid beta and tau cooperate to cause neurodegeneration. We recently generated a mouse model (APP/PS1 + Tau) that develops amyloid plaque pathology and expresses human tau in the absence of endogenous murine tau. These mice exhibit an age-related behavioural hyperactivity phenotype and transcriptional deficits which are ameliorated by tau transgene suppression. We hypothesized that these mice would also display memory and hippocampal synaptic plasticity deficits as has been reported for many plaque bearing mouse models which express endogenous mouse tau. We observed that our APP/PS1 + Tau model does not exhibit novel object memory or robust long-term potentiation deficits with age, whereas the parent APP/PS1 line with mouse tau did develop the expected deficits. These data are important as they highlight potential functional differences between mouse and human tau and the need to use multiple models to fully understand Alzheimer's disease pathogenesis and develop effective therapeutic strategies.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Precursor de Proteína beta-Amiloide/genética , Animais , Modelos Animais de Doenças , Humanos , Potenciação de Longa Duração , Camundongos , Camundongos Transgênicos , Placa Amiloide , Presenilina-1 , Proteínas tau/genética
11.
Mol Pharm ; 18(1): 87-100, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33231464

RESUMO

Pancreatic ductal adenocarcinoma (PDAC), a metabolic disorder, remains one of the leading cancer mortality sources worldwide. An initial response to treatments, such as gemcitabine (GEM), is often followed by emergent resistance reflecting an urgent need for alternate therapies. The PDAC resistance to GEM could be due to ERK1/2 activity. However, successful ERKi therapy is hindered due to low ligand efficiency, poor drug delivery, and toxicity. In this study, to overcome these limitations, we have designed pH-responsive nanoparticles (pHNPs) with a size range of 100-150 nm for the simultaneous delivery of ERKi (SCH 772984) and GEM with tolerable doses. These pHNPs are polyethylene glycol (PEG)-containing amphiphilic polycarbonate block copolymers with tertiary amine side chains. They are systemically stable and capable of improving in vitro and in vivo drug delivery at the cellular environment's acidic pH. The functional analysis indicates that the nanomolar doses of ERKi or GEM significantly decreased the 50% growth inhibition (IC50) of PDAC cells when encapsulated in pHNPs compared to free drugs. The combination of ERKi with GEM displayed a synergistic inhibitory effect. Unexpectedly, we uncover that the minimum effective dose of ERKi significantly promotes GEM activities on PDAC cells. Furthermore, we found that pHNP-encapsulated combination therapy of ERKi with GEM was superior to unencapsulated combination drug therapy. Our findings, thus, reveal a simple, yet efficient, drug delivery approach to overcome the limitations of ERKi for clinical applications and present a new model of sensitization of GEM by ERKi with no or minimal toxicity.


Assuntos
Proliferação de Células/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Portadores de Fármacos/química , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Nanopartículas/química , Neoplasias Pancreáticas/tratamento farmacológico , Inibidores de Proteínas Quinases/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Carcinoma Ductal Pancreático/tratamento farmacológico , Linhagem Celular Tumoral , Desoxicitidina/administração & dosagem , Desoxicitidina/química , Sistemas de Liberação de Medicamentos/métodos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Camundongos , Camundongos Nus , Polietilenoglicóis/química , Polímeros/química , Inibidores de Proteínas Quinases/química , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Gencitabina
12.
Acta Oncol ; 60(4): 505-512, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33491521

RESUMO

PURPOSE/OBJECTIVES: A recent study has shown that tight conformity of lung Stereotactic Ablative Radiotherapy (SABR) plans might worsen loco-regional control and can predict distant metastases. The study aims to report overall survival (OS), progression-free survival (PFS), local recurrence free survival (LRFS), and dosimetry of early-stage lung cancer patients treated with SABR and to try to explore any dosimetric predictor of outcomes. MATERIAL AND METHODS: Patients treated in our institute (May 2009-August 2018) were included. Electronic medical records were reviewed for baseline characteristics, treatment details, and outcomes. Dosimetric data were extracted from Xio and Monaco software. Patients were treated according to the United Kingdom (UK) SABR consortium guidelines. Kaplan-Meier's analysis with log-rank test was used for survival analysis. The univariate and multivariable Cox regression model was used for correlating dosimetric variables and outcomes. RESULTS: We treated 1266 patients with median age of 75 years and 47.4% were male. Median follow up was 56 months. Median OS was 36 months with 1, 2, and 5 years OS of 84.2%, 64.5%, and 31.5%, respectively. Median for PFS and LRFS was not reached. One, 2, and 5 years PFS were 87.4%, 78.4%, and 72.5%, respectively. One, 2, and 5 years LRFS were 98.2%, 95.1%, and 92.5%, respectively. Planning target volume (PTV), dose to 99% volume of PTV (D99), and R50 (volume receiving the 50% dose/volume (PTV)) were significantly associated with OS. PTV, mean lung dose (MLD), V20 (volume of lung minus gross tumour volume (GTV) receiving 20 Gy), V12.5 (volume of lung minus GTV receiving 12.5 Gy), and dose fractionation were significantly associated with PFS. Nothing was associated with LRFS on univariate analysis. R100 of >1.1 was associated with better OS, PFS, and LRFS compared to R100 ≤ 1.1. CONCLUSION: SABR achieves good clinical outcomes in patients with early-stage lung cancer; even in elderly patients with multiple comorbidities. In the largest UK early lung cancer cohort treated with SABR, we found that dosimetry correlates with clinical outcomes. Further validation of these results is needed to guide future optimisation of SABR delivery.


Assuntos
Neoplasias Pulmonares , Radiocirurgia , Idoso , Humanos , Recém-Nascido , Pulmão , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia , Masculino , Estudos Retrospectivos , Reino Unido
13.
J Liposome Res ; 31(4): 381-388, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33183121

RESUMO

The aim of the current study was to develop the phytosomal gel of aloe vera extract for improved topical delivery. Aloe vera extract loaded phytosomal system was developed by fixing the amount of aloe vera extract and ethanol and by varying the concentration of lecithin (0.15-0.25% w/v) and speed of rotation (80-120 rpm). Different formulation batches were prepared as per the Design expert software. A 22 Factorial design was applied to optimize the formulation on the basis of vesicular size and entrapment efficiency. Developed formulations were evaluated for vesicular size, entrapment efficiency, PDI, zeta potential and in-vitro release. Further stability studies were also performed. For the optimized formulation (F09), vesicular size, entrapment efficiency and PDI were found as 123.1 ± 1.44 nm, 95.67 ± 0.27% and 0.98 ± 0.06. Zeta potential of -11.9 mV and drug release of 56.91 ± 4.1% obtained in 24 h. Drug release kinetics from the phytosomes follows Higuchi model. TEM micrograph confirms the uniform structure of phytosomes. Phytosomal gel of optimized phytosomal formulation (F09) was developed with 1% Carbopol 934 and physically characterized on the basis of pH, viscosity, homogeneity and drug content. Ex-vivo permeation study showed the better permeation and flux profile of phytosomal gel with the conventional aloe vera extract gel. Also, studies on phytosomal formulation and gel showed stability up-to 3 months. Thus overall, it can be concluded that the phytosomal gel is a good carrier for topical delivery of herbal extract such as aloe vera.


Assuntos
Aloe , Liberação Controlada de Fármacos , Lipossomos , Extratos Vegetais , Viscosidade
14.
J Vasc Bras ; 20: e20210008, 2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34188672

RESUMO

BACKGROUND: Variations in the upper limb arterial pattern are commonplace and necessitate complete familiarity for successful surgical and interventional procedures. Variance in the vascular tree may involve any part of the axis artery of the upper limb, including the axillary artery and brachial artery or its branches, in the form of radial and ulnar arteries, which eventually supply the hand via anastomosing arches. OBJECTIVES: To study the peculiarities of the arterial pattern of the upper limb and to correlate them with embryological development. METHODS: The entire arterial branching of forty-two upper limbs of formalin fixed adult human cadavers was examined during routine dissection for educational purposes, conducted over a 3-year period in the Department of Anatomy, Lady Hardinge Medical College, New Delhi. RESULTS: The study found: 1) One case in which a common trunk arose from the third part of the axillary artery, which immediately splayed into four branches (2.4%); 2) High division of the brachial artery into ulnar and radial arteries, in 3 cases (7.1%); 3) Pentafurcation of the brachial artery into ulnar, interosseus, radial, and radial recurrent arteries and a muscular twig to the brachioradialis in 1/42 cases (2.4%); 4) Incomplete Superficial Palmar arch in 3/42 cases (7.1%); and 5) Presence of a median artery in 2/42 case(4.8%). CONCLUSIONS: This study observed and described the varied arterial patterns of the upper limb and identified the various anomalous patterns, supplementing the surgeon's armamentarium in various surgical procedures, thereby helping to prevent complications or failures of reconstructive surgeries, bypass angiography, and many similar procedures.


CONTEXTO: As variações no padrão arterial dos membros superiores são comuns e, assim, necessitam de total familiaridade para que os procedimentos cirúrgicos e de intervenção sejam bem-sucedidos. A variância na árvore vascular pode envolver qualquer parte da artéria axial dos membros superiores, incluindo a artéria axilar, a artéria braquial ou os seus ramos, na forma das artérias radial e ulnar, as quais, em algum momento, suprem as mãos através dos arcos anastomosados. OBJETIVOS: Avaliar as peculiaridades do padrão arterial dos membros superiores e correlacioná-las ao desenvolvimento embriológico. MÉTODOS: Foram examinados os ramos arteriais completos de 42 membros superiores de cadáveres adultos conservados em formalina, os quais eram rotineiramente dissecados para fins educacionais durante 3 anos no Departamento de Anatomia Lady Hardinge Medical College, Nova Delhi. RESULTADOS: O estudo apresentou cinco desfechos. 1. Foi constatado um caso em que um tronco comum surgiu da terceira parte da artéria axilar que imediatamente se disseminou em quatro ramos (2,4%). 2. Houve divisão maior da artéria braquial em artérias ulnar e radial em três casos (7,1%). 3. Em um caso, ocorreu pentafurcação da artéria braquial em ulnar, interóssea, radial, radial recorrente e de um galho muscular em braquiorradial (2,4%). 4. Foi constatado arco palmar superficial incompleto em três dos 42 casos (7,1%). 5. Foi observada a presença da artéria mediana em 2 dos 42 casos (4,8%). CONCLUSÕES: Este estudo compreende o padrão arterial do membro superior e identifica os diversos padrões anômalos para agregar ao arsenal terapêutico de cirurgiões para diversos procedimentos cirúrgicos, com o objetivo de combater quaisquer complicações ou falhas de cirurgias reconstrutivas, de angiografias de cirurgias de revascularização e muitas outras.

15.
Drug Dev Ind Pharm ; 46(1): 50-56, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31818154

RESUMO

The major drawback of the eye drops is rapid elimination of drug from the precorneal region, thus ensuing poor bioavailability as well as therapeutic efficacy. To conquer these limitations, a pH triggered in situ gel was developed for sustained delivery of levofloxacin. Two polymers namely hydroxypropyl methylcellulose (HPMC) and sodium alginate along with the boric acid buffer were used to formulate the in situ gel. Based on the various physicochemical evaluation parameters like pH, clarity and gelling capacity placebo formulations were selected and further characterized for viscosity, in vitro release, ex vivo corneal permeation, and histopathological studies. The optimized in situ gel (F28) showed sustained release of 93 ± 4.23% for 24 h and cumulative drug permeation of 71.81 ± 4.7% for 72 h. Additionally, ocular irritation study and histopathology of the formulation treated cornea confirm the non-irritancy of the optimized formulation. Based on all the above performed studies, it can be concluded that the in situ gel would present a fruitful alternative for the ocular infections.


Assuntos
Antibacterianos/administração & dosagem , Sistemas de Liberação de Medicamentos , Cabras/metabolismo , Levofloxacino/administração & dosagem , Administração Oftálmica , Alginatos/química , Animais , Antibacterianos/química , Antibacterianos/toxicidade , Córnea/metabolismo , Preparações de Ação Retardada , Géis , Concentração de Íons de Hidrogênio , Derivados da Hipromelose/química , Levofloxacino/química , Levofloxacino/toxicidade , Viscosidade
16.
J Neurovirol ; 25(3): 289-300, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30693421

RESUMO

Human T cell leukemia virus type 1 (HTLV-1) and Zika virus (ZIKV) have been considered neglected viruses of low public health concern until recently when incidences of HTLV-1 and ZIKV were observed to be linked to serious immune-related disease and neurological complications. This review will discuss the epidemiology, genomic evolution, virus-host interactions, virulence factors, neuropathological sequelae, and current perspectives of these reemerging viruses. There are no FDA-approved therapeutics or vaccines against these viruses, and as such, it is important for clinical trials to focus on developing vaccines that can induce cell-mediated immune response to confer long-term protective immunity. Furthermore, attention should be paid to reducing the transmission of these viruses through unprotected sex, infected blood during sharing of contaminated needles, donated blood and organs, and vertical transmission from mother to baby via breastfeeding. There is an urgent need to re-evaluate repurposing current antiviral therapies as well as developing novel antiviral agents with enhanced efficacy due to the high morbidity rate associated with these two reemerging chronic viral diseases.


Assuntos
Infecções por HTLV-I , Infecção por Zika virus , Vírus Linfotrópico T Tipo 1 Humano , Humanos , Saúde Pública , Zika virus
17.
Cancer Invest ; 37(9): 453-462, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31469000

RESUMO

Cancer is a proficient evader of the immune system and is responsible for a high number of deaths annually. Most of these cancer cases are associated with genetic mutations, viruses, radiations or other carcinogenic substances like tobacco smoke. However, a significant number of cases arise as a result of infection by certain parasitic organisms other than viruses. This review tries to explore various less studied mechanisms by which these parasites induce cancer and lead to its progression. The changes brought by organisms in the genetic makeup are enumerated along with the effects of various protein products synthesised by these organisms.


Assuntos
Infecções Bacterianas/complicações , Micoses/complicações , Neoplasias/etiologia , Doenças Parasitárias/complicações , Animais , Infecções Bacterianas/genética , Carcinogênese , Progressão da Doença , Redes Reguladoras de Genes , Humanos , Micoses/genética , Neoplasias/genética , Doenças Parasitárias/genética
18.
J Immunol ; 198(5): 2156-2164, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28130493

RESUMO

Necroptosis is a form of programmed cell death defined by activation of the kinase receptor interacting protein kinase 3 and its downstream effector, the pseudokinase mixed lineage kinase domain-like (MLKL). Activated MLKL translocates to the cell membrane and disrupts it, leading to loss of cellular ion homeostasis. In this study, we use a system in which this event can be specifically triggered by a small-molecule ligand to show that MLKL activation is sufficient to induce the processing and release of bioactive IL-1ß. MLKL activation triggers potassium efflux and assembly of the NLRP3 inflammasome, which is required for the processing and activity of IL-1ß released during necroptosis. Notably, MLKL activation also causes cell membrane disruption, which allows efficient release of IL-1ß independently of the recently described pyroptotic effector gasdermin-D. Taken together, our findings indicate that MLKL is an endogenous activator of the NLRP3 inflammasome, and that MLKL activation provides a mechanism for concurrent processing and release of IL-1ß independently of gasdermin-D.


Assuntos
Apoptose , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Monócitos/fisiologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Necrose , Proteínas Quinases/metabolismo , Linhagem Celular , Membrana Celular/metabolismo , Homeostase , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas de Neoplasias/metabolismo , Proteínas de Ligação a Fosfato , Potássio/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo
19.
Am J Respir Crit Care Med ; 198(8): 1074-1084, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-29688024

RESUMO

RATIONALE: Respiratory syncytial virus (RSV) bronchiolitis is a major cause of morbidity and mortality in infancy. Severe disease is believed to result from uncontrolled viral replication, an excessive immune response, or both. OBJECTIVES: To determine RSV load and immune mediator levels in nasal mucosal lining fluid by serial sampling of nasal fluids from cases of moderate and severe bronchiolitis over the course of infection. METHODS: Infants with viral bronchiolitis necessitating admission (n = 55) were recruited from a pediatric center during 2016 and 2017. Of these, 30 were RSV infected (18 "moderate" and 12 mechanically ventilated "severe"). Nasal fluids were sampled frequently over time using nasosorption devices and nasopharyngeal aspiration. Hierarchical clustering of time-weighted averages was performed to investigate cytokine and chemokine levels, and gene expression profiling was conducted. MEASUREMENTS AND MAIN RESULTS: Unexpectedly, cases with severe RSV bronchiolitis had lower nasal viral loads and reduced IFN-γ and C-C chemokine ligand 5/RANTES (regulated upon activation, normal T cell expressed and secreted) levels than those with moderate disease, especially when allowance was made for disease duration (all P < 0.05). Reduced cytokine/chemokine levels in severe disease were also seen in children with other viral infections. Gene expression analysis of nasopharyngeal aspiration samples (n = 43) confirmed reduced type-I IFN gene expression in severe bronchiolitis accompanied by enhanced expression of MUC5AC and IL17A. CONCLUSIONS: Infants with severe RSV bronchiolitis have lower nasal viral load, CXCL10 (C-X-C motif chemokine ligand 10)/IP-10, and type-I IFN levels than moderately ill children, but enhanced MUC5AC (mucin-5AC) and IL17A gene expression in nasal cells.


Assuntos
Bronquiolite Viral/virologia , Interferons/metabolismo , Mucosa Nasal/virologia , Insuficiência Respiratória/virologia , Infecções por Vírus Respiratório Sincicial/virologia , Bronquiolite Viral/imunologia , Quimiocinas/metabolismo , Citocinas/metabolismo , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Mucosa Nasal/imunologia , Insuficiência Respiratória/imunologia , Infecções por Vírus Respiratório Sincicial/imunologia , Transcriptoma , Carga Viral
20.
J Environ Manage ; 242: 210-219, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31039530

RESUMO

The present study successfully demonstrates greener methodology of hydrodynamic cavitation using rotational flows for disinfection of water. Disinfection of two model microbial strains-gram- negative (Escherichia coli) and gram-positive (Staphylococcus aureus) using vortex diode was evaluated. The removal efficacy was quantified for two different cavitation reactors. Practically complete elimination of E. coli was achieved (99%) after 1 h of cavitation at a pressure drop of only 0.5 bar. However, elimination of S. aureus using vortex diode was observed to be lower in comparison to the removal of E. coli and only 60% disinfection could be achieved under similar conditions, which can be subsequently enhanced up to 98% by increasing pressure drop. The results were compared with another cavitating device that employs linear flow for cavitation, orifice. The reactor geometry has significant impact on the disinfection process and orifice was found to require significantly higher pressure drop (10 bar) conditions for disinfection and for eliminating gram-positive bacteria with high efficiency. A plausible mechanism for disinfection was proposed to elucidate the role of cavitation in cell destruction leading to death of cells through the rupture of cell wall, oxidative damage and possible DNA denaturation. Also, a cavitation model using per pass disinfection was developed that can provide meaningful physical description of the disinfection process as against the conventional first order reaction rate model. This study would provide meaningful insight into cavitation process based on hydrodynamic cavitation for the destruction of both gram-negative and gram-positive bacteria from various water sources, including industrial wastewaters.


Assuntos
Hidrodinâmica , Purificação da Água , Desinfecção , Escherichia coli , Staphylococcus aureus , Água
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