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1.
Pharm Res ; 39(6): 1047-1064, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35619043

RESUMO

Cytoplasmic delivery of bioactives requires the use of strategies such as active transport, electroporation, or the use of nanocarriers such as polymeric nanoparticles, liposomes, micelles, and dendrimers. It is essential to deliver bioactive molecules in the cytoplasm to achieve targeted effects by enabling organelle targeting. One of the biggest bottlenecks in the successful cytoplasmic delivery of bioactives through nanocarriers is their sequestration in the endosomes that leads to the degradation of drugs by progressing to lysosomes. In this review, we discussed mechanisms by which nanocarriers are endocytosed, the mechanisms of endosomal escape, and more importantly, the strategies that can be and have been employed for their escape from the endosomes are summarized. Like other nanocarriers, polymeric micelles can be designed for endosomal escape, however, a careful control is needed in their design to balance between the possible toxicity and endosomal escape efficiency. Keeping this in view, polyion complex micelles, and polymers that have the ability to escape the endosome, are fully discussed. Finally, we provided some perspectives for designing the polymeric micelles for efficient cytoplasmic delivery of bioactive agents through endosomal escape.


Assuntos
Micelas , Nanopartículas , Endocitose , Endossomos/metabolismo , Polímeros/metabolismo
2.
Pharm Res ; 39(6): 1115-1134, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35386012

RESUMO

Cancer is associated with a comprehensive burden that significantly affects patient's quality of life. Even though patients' disease condition is improving following conventional therapies, researchers are studying alternative tools that can penetrate solid tumours to deliver the therapeutics due to issues of developing resistance by the cancer cells. Treating cancer is not the only the goal in cancer therapy; it also includes protecting non-cancerous cells from the toxic effects of anti-cancer agents. Thus, various advanced techniques, such as cell-based drug delivery, bacteria-mediated therapy, and nanoparticles, are devised for site-specific delivery of drugs. One of the novel methods that can be targeted to deliver anti-cancer agents is by utilising genetically modified non-pathogenic bacterial species. This is due to the ability of bacterial species to multiply selectively or non-selectively on tumour cells, resulting in biofilms that leads to disruption of metastasis process. In preclinical studies, this technology has shown significant results in terms of efficacy, and some are currently under investigation. Therefore, researchers have conducted studies on bacteria transporting the anti-cancer drug to targeted tumours. Alternatively, bacterial ghosts and bacterial spores are utilised to deliver anti-cancer drugs. Although in vivo studies of bacteria-mediated cancer therapy have shown successful outcome, further research on bacteria, specifically their targeting mechanism, is required to establish a complete clinical approach in cancer treatment. This review has focused on the up-to-date understanding of bacteria as a therapeutic carrier in the treatment of cancer as an emerging field.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Bactérias , Sistemas de Liberação de Medicamentos , Excipientes , Humanos , Neoplasias/patologia , Qualidade de Vida
3.
J Assoc Physicians India ; 70(8): 11-12, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36082725

RESUMO

BACKGROUND: Diabetic nephropathy (DN) is an important and catastrophic complication of diabetes mellitus (DM). Kidney disease has heterogeneity in histology in diabetes patients and includes both diabetic kidney disease (DKD) (albuminuric or nonalbuminuric) and nondiabetic kidney disease (NDKD) either in isolation or in coexistence with DN. Diabetic nephropathy is hard to overturn. While NDKD is treatable and reversible. MATERIALS AND METHODS: We enrolled a total of 50 type 2 diabetes mellitus (T2DM) patients with clinical kidney disease, of both genders and age >18 years, who underwent kidney biopsy from October 2016 to October 2018. Patients with proteinuria <30 mg per day were excluded from the study. The indications of the renal biopsy were nephrotic syndrome (NS), active urinary sediment, rapid decline in renal function, asymptomatic proteinuria, and hematuria. RESULT: A total of 50 (males: 42 and females: eight) patients with T2DM who underwent kidney biopsy were enrolled. The clinical presentation was: NS 26 (52%), chronic kidney disease (CKD) 11 (22%), asymptomatic proteinuria and hematuria six (12%), acute kidney injury (AKI) four (8%), and acute nephritic syndrome (ANS) three (6%). Diabetic retinopathy (DR) was noted in 19 (38%) cases. Kidney biopsy revealed isolated DN, isolated NDKD, and NDKD superimposed on DN in 26 (52%), 14 (28%), and 10 (20%) cases, respectively. Idiopathic membranous nephropathy (MN) (4) and amyloidosis (2) were the most common forms of NDKD, whereas diffuse proliferative glomerulonephritis (DPGN) was the main form of NDKD superimposed on DN. Diabetic nephropathy was observed in 15 (79%) cases in presence of DR and also in 11 (35.5%) cases even in absence of DR. Of eight patients with microalbuminuria four (50%) cases have biopsy-proven DN. CONCLUSION: About 48% of patients had NDKD either in isolation or in coexistence with DN. Diabetic nephropathy was found in absence of DR and in patients with a low level of proteinuria. The level of proteinuria and presence of DR does not help to distinguish DN vs NDKD. Hence, renal biopsy may be useful in selected T2DM patients with clinical kidney disease to diagnose NDKD.


Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Retinopatia Diabética , Glomerulonefrite , Síndrome Nefrótica , Adolescente , Biópsia , Diabetes Mellitus Tipo 2/diagnóstico , Nefropatias Diabéticas/complicações , Nefropatias Diabéticas/diagnóstico , Feminino , Glomerulonefrite/complicações , Hematúria , Humanos , Rim/patologia , Masculino , Síndrome Nefrótica/complicações , Proteinúria/etiologia , Estudos Retrospectivos
4.
J Assoc Physicians India ; 67(9): 18-22, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31561682

RESUMO

INTRODUCTION: The safe and effective treatment of HIV-associated renal diseases with cART can decrease the progression to ESRD and also improve the morbidity and mortality secondary to renal failure. MATERIAL AND METHODS: HIV positive patients with clinical kidney disease were the subjects of this study. The diagnosis of HIV was established using immunochromatographic assays. The patients were subjected to meticulous history, physical examination, laboratory investigations and kidney biopsy. Patients were treated with combined antiretroviral therapy and enalapril. They were followed at 3 months interval for one year. Short term outcome was assessed using changes in serum creatinine and proteinuria. Long term outcome assessments were done using progression to end stage renal disease and patients survival. RESULT: Ten (Male=7; Female=3) HIV patients with clinical renal disease were included in this study. Their age ranged between 26-55 (Mean=40.5±8.8) years. The mean serum creatinine at the baseline, three, six, nine and twelve months was 2.46, 2.09, 2.43, 2.46 and 2.58 mg/dl respectively. The mean e-GFR by MDRD equation at 0, 3, 6, 9 and 12 months was 40.9, 45.5, 48.2, 51.1 and 52.5 ml/ min/1.73m2 respectively. The mean twenty four hour urinary protein excretion at 0, 3, 6, 9 and 12 months was 3.01, 2.82, 2.22, 2.02 and 1.79 grams respectively. Six patients showed improvement in creatinine and e-GFR, whereas worsening of renal function was seen in four patients. Proteinuria decreased in seven patients, whereas it remained unchanged in three patients. There was no mortality at the end of one year of follow up. CONCLUSION: Treatment with combined ART and ACEIs slows the progression of HIV-associated kidney disease, decreases proteinuria and improves the GFR.


Assuntos
Antirretrovirais/uso terapêutico , Quimioterapia Combinada , Infecções por HIV/complicações , Nefropatias/terapia , Adulto , Creatinina , Feminino , Seguimentos , Taxa de Filtração Glomerular , HIV , Humanos , Rim , Falência Renal Crônica , Masculino , Pessoa de Meia-Idade , Proteinúria
5.
J Assoc Physicians India ; 67(11): 18-21, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31793263

RESUMO

INTRODUCTION: Crescentic Glomerulonephritis (CGN) is most aggressive structural phenotype and accounts for 2%-7% of renal biopsy in most series. The aim of study was to assess the clinical feature and outcome of CGN at our centre. MATERIAL AND METHODS: The renal biopsy performed during the period of January 2015 to January 2018 was studied and patients showing crescentic glomerulonephritis on histology were selected for this study. The clinical presentation, immunological assay, biochemical and haematological investigations, treatment protocol and final outcome at three month of these patients were analysed in the present study. RESULTS: Of 380 biopsy, 26 (male=17, female=9) patients had histological evidence of CGN (6.8%). The age of patients ranged between 13-75 (mean=43) years. Fibro cellular and cellular crescent was noted in 84.61% and 15.38% of patients respectively. Small vessels vasculitis and granuloma was observed in 5 (19.23%) cases. Based on immunohistopathology, we observed type I (n=3), type II (n=8), type III (n=5), type IV (n=3), and type V (n=7) crescentic GN in 11.53%, 30.76%, 19.23%, 11.53% and 26.92% of patients respectively. Haemodialysis was given to 22(84.61%) and 4(15.38%) patients were treated with immunosuppressive therapy. Plasmapheresis was used in two double positive (ANCA + Anti GBM Ab) patients. Remaining 21(80.76%) has progressed to ESRD over a period of 2-3 months. CONCLUSION: Type II (immune complex) CGN was most common type followed by type V (immune negative) and type III (pauci-immune) CGN. The crescentic GN had worse prognosis with >80% of patients progressed to ESRD within 3 month of time from onset of illness. Early diagnosis and treatment is associated with favourable outcome.


Assuntos
Glomerulonefrite , Vasculite , Anticorpos Anticitoplasma de Neutrófilos , Biópsia , Feminino , Glomerulonefrite/complicações , Glomerulonefrite/etiologia , Glomerulonefrite/terapia , Humanos , Masculino , Estudos Retrospectivos , Vasculite/etiologia
6.
Matern Child Nutr ; 15(3): e12815, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30903804

RESUMO

Stunting in children is a global public health concern. We investigated how global DNA methylation relates to food intakes, dietary diversity, and development of stunting among 324 children aged 24-36 months in a slum community in Dhaka, Bangladesh. Stunted children (height-for-age z score ˂-2; n = 162) and their age- and sex-matched nonstunted counterparts (height-for-age z score ˃-1; n = 162) were selected by active community surveillance. We studied global DNA methylation, measured as 5-mC% content in whole blood. Dietary intake, anthropometric measurement, and sociodemographic information were obtained. In the multiple linear regression model, increased global DNA methylation level in children was significantly associated with consumption of lower amount of energy, coef: .034 (95% CI [.014, .053]); P = .001, protein, coef: .038 (95% CI [.019, .057]); P = .000, carbohydrate, coef: .027 (95% CI [.008, .047]); P = .006, zinc, coef: .020 (95% CI [.001, .039]); P = .043, total dietary intakes, coef: .020 (95% CI [.001, .039]); P = .043, and intake from plant sources, coef: .028 (95% CI [.009, .047]); P = .005, after adjusting for other covariates. Moreover, higher fruits and vegetables consumption was significantly associated with lower 5-mC% level, coef: -.022 (95% CI [-.041, -.002]); P = .028. Our findings suggest a significant association between low dietary intakes and increased global DNA methylation. We also found increased global DNA methylation in stunted children. To establish the relationship among the macronutrient intakes, global DNA methylation, and stunting, future prospective studies are warranted in resource-poor settings.


Assuntos
Metilação de DNA , Carboidratos da Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Ingestão de Energia/etnologia , Transtornos do Crescimento/genética , Áreas de Pobreza , Bangladesh/epidemiologia , Fenômenos Fisiológicos da Nutrição Infantil , Pré-Escolar , Estudos Transversais , Inquéritos sobre Dietas , Epigênese Genética , Humanos , Oligoelementos/administração & dosagem , População Urbana , Vitaminas/administração & dosagem
7.
Biochim Biophys Acta Proteins Proteom ; 1866(5-6): 722-730, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29654975

RESUMO

Retromer complex plays a crucial role in intracellular protein trafficking and is conserved throughout the eukaryotes including malaria parasite, Plasmodium falciparum, where it is partially conserved. The assembly of retromer complex in RBC stages of malarial parasite is extremely difficult to explore because of its complicated physiology, small size, and intra-erythrocytic location. Nonetheless, understanding of retromer assembly may pave new ways for the development of novel antimalarials targeting parasite-specific protein trafficking pathways. Here, we investigated the assembly of retromer complex in P. falciparum, by an immunosensing method through highly sensitive Surface Plasmon Resonance (SPR) technique. After taking leads from the bioinformatics search and literature, different interacting proteins were identified and specific antibodies were raised against them. The sensor chip was prepared by covalently linking antibody specific to one component and the whole cell lysate was passed through it in order to trap the interacting complex. Antibodies raised against other interacting components were used to detect them in the trapped complex on the SPR chip. We were able to detect three different components in the retromer complex trapped by the immobilized antibody specific against a different component on a sensor chip. The assay was reproduced and validated in a different two-component CD74-MIF system in mammalian cells. We, thus, illustrate the assembly of retromer complex in P. falciparum through a bio-sensing approach that combines SPR with immunosensing requiring a very small amount of sample from the native source.


Assuntos
Técnicas Biossensoriais , Complexos Multiproteicos/metabolismo , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/metabolismo , Ressonância de Plasmônio de Superfície , Proteínas de Transporte Vesicular/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Western Blotting , Biologia Computacional , Células Hep G2 , Humanos , Imunoprecipitação , Cinética , Camundongos , Complexos Multiproteicos/genética , Complexos Multiproteicos/imunologia , Células NIH 3T3 , Plasmodium falciparum/genética , Plasmodium falciparum/imunologia , Ligação Proteica , Transporte Proteico , Proteínas de Protozoários/genética , Proteínas de Protozoários/imunologia , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/imunologia
8.
BMC Psychiatry ; 17(1): 281, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28826398

RESUMO

BACKGROUND: Autism spectrum disorders (ASD) are a group of complex neurodevelopmental disorders. The prevalence of ASD in many South Asian countries is still unknown. The aim of this study was to systematically review available epidemiological studies of ASD in this region to identify gaps in our current knowledge. METHODS: We searched, collected and evaluated articles published between January 1962 and July 2016 which reported the prevalence of ASD in eight South Asian countries. The search was conducted in line with the PRISMA guidelines. RESULTS: We identified six articles from Bangladesh, India, and Sri Lanka which met our predefined inclusion criteria. The reported prevalence of ASD in South Asia ranged from 0.09% in India to 1.07% in Sri Lanka that indicates up to one in 93 children have ASD in this region. Alarmingly high prevalence (3%) was reported in Dhaka city. Study sample sizes ranged from 374 in Sri Lanka to 18,480 in India. The age range varied between 1 and 30 years. No studies were found which reported the prevalence of ASD in Pakistan, Nepal, Bhutan, Maldives and Afghanistan. This review identifies methodological differences in case definition, screening instruments and diagnostic criteria among reported three countries which make it very difficult to compare the studies. CONCLUSIONS: Our study is an attempt at understanding the scale of the problem and scarcity of information regarding ASD in the South Asia. This study will contribute to the evidence base needed to design further research and make policy decisions on addressing this issue in this region. Knowing the prevalence of ASD in South Asia is vital to ensure the effective allocation of resources and services.


Assuntos
Povo Asiático/psicologia , Povo Asiático/estatística & dados numéricos , Transtorno do Espectro Autista/epidemiologia , Bangladesh/epidemiologia , Humanos , Índia/epidemiologia , Sri Lanka/epidemiologia
9.
Antimicrob Agents Chemother ; 60(7): 4217-28, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27139466

RESUMO

We synthesized a new series of conjugated hydrazones that were found to be active against malaria parasite in vitro, as well as in vivo in a murine model. These hydrazones concentration-dependently chelated free iron and offered antimalarial activity. Upon screening of the synthesized hydrazones, compound 5f was found to be the most active iron chelator, as well as antiplasmodial. Compound 5f also interacted with free heme (KD [equilibrium dissociation constant] = 1.17 ± 0.8 µM), an iron-containing tetrapyrrole released after hemoglobin digestion by the parasite, and inhibited heme polymerization by parasite lysate. Structure-activity relationship studies indicated that a nitrogen- and sulfur-substituted five-membered aromatic ring present within the benzothiazole hydrazones might be responsible for their antimalarial activity. The dose-dependent antimalarial and heme polymerization inhibitory activities of the lead compound 5f were further validated by following [(3)H]hypoxanthine incorporation and hemozoin formation in parasite, respectively. It is worth mentioning that compound 5f exhibited antiplasmodial activity in vitro against a chloroquine/pyrimethamine-resistant strain of Plasmodium falciparum (K1). We also evaluated in vivo antimalarial activity of compound 5f in a murine model where a lethal multiple-drug-resistant strain of Plasmodium yoelii was used to infect Swiss albino mice. Compound 5f significantly suppressed the growth of parasite, and the infected mice experienced longer life spans upon treatment with this compound. During in vitro and in vivo toxicity assays, compound 5f showed minimal alteration in biochemical and hematological parameters compared to control. In conclusion, we identified a new class of hydrazone with therapeutic potential against malaria.


Assuntos
Antimaláricos/farmacologia , Benzotiazóis/farmacologia , Hidrazonas/farmacologia , Animais , Antimaláricos/síntese química , Antimaláricos/química , Benzotiazóis/síntese química , Benzotiazóis/química , Cloroquina/química , Cloroquina/farmacologia , Resistência a Múltiplos Medicamentos , Hidrazonas/síntese química , Hidrazonas/química , Ferro/química , Masculino , Camundongos , Plasmodium falciparum/efeitos dos fármacos , Plasmodium yoelii/efeitos dos fármacos , Pirimetamina/química , Pirimetamina/farmacologia
10.
Mol Pharm ; 13(12): 4179-4190, 2016 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-27934479

RESUMO

This study investigated the potential of chitosan-coated mixed micellar nanocarriers (polyplexes) for codelivery of siRNA and doxorubicin (DOX). DOX-loaded mixed micelles (serving as cores) were prepared by thin film hydration method and coated with chitosan (CS, serving as outer shell), and complexed with multidrug resistance (MDR) inhibiting siRNA. Selective targeting was achieved by folic acid conjugation. The polyplexes showed pH-responsive enhanced DOX release in acidic tumor pH, resulting in higher intracellular accumulation, which was further augmented by downregulation of mdr-1 gene after treatment with siRNA-complexed polyplexes. In vitro cytotoxicity assay demonstrated an enhanced cytotoxicity in native 4T1 and multidrug-resistant 4T1-mdr cell lines, compared to free DOX. Furthermore, in vivo, polyplexes codelivery resulted in highest DOX accumulation and significantly reduced the tumor volume in mice with 4T1 and 4T1-mdr tumors as compared to the free DOX groups, leading to improved survival times in mice. In conclusion, codelivery of siRNA and DOX via polyplexes has excellent potential as targeted drug nanocarriers for treatment of MDR cancers.


Assuntos
Neoplasias da Mama/terapia , Quitosana/química , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Resistência a Múltiplos Medicamentos , Nanopartículas/administração & dosagem , Polímeros/administração & dosagem , RNA Interferente Pequeno/genética , Animais , Antibióticos Antineoplásicos/farmacologia , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Portadores de Fármacos , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Polietilenoglicóis , Polímeros/química
11.
Protein Expr Purif ; 120: 7-15, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26690372

RESUMO

Translocation of various proteins to the subcellular organelles is an essential mechanism to regulate the metabolic pathways and often vacuolar protein sorting (VPS) proteins are involved in this transportation. Plasmodium falciparum VPS29 (PfVPS29) is predicted to be a functional component in the assembly of the retromer complex; however, so far detailed characterization of PfVPS29 in its native form is not yet done. We report the successful expression and purification of tag-free recombinant PfVPS29 with a yield of 5.6 mg from 1 L of Escherichia coli culture. PfVPS29 was purified by combined anion-exchange and size exclusion chromatography. The protein showed a single band in SDS-PAGE and it exhibited molecular mass of 21.7 kDa as measured by MALDI-TOF mass spectrometry. Secondary structure was elucidated by circular dichroism spectroscopy. It was found to be a monomeric protein in solution as evident from dynamic light scattering studies, chemical cross-linking experiments and size exclusion chromatography. Subsequently, polyclonal anti-PfVPS29 antibody was generated and used for evaluating protein expression by western blot and following subcellular localization in P. falciparum by confocal immunofluoroscence microscopy. PfVPS29 was found to be located in cytoplasm and expressed from early trophozoite to schizont stages with maximum expression in trophozoite stage. This study provides purification, biophysical characterization and subcellular localization of PfVPS29 in different asexual stages of P. falciparum.


Assuntos
Plasmodium falciparum/metabolismo , Proteínas de Protozoários/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Sequência de Aminoácidos , Western Blotting , Dicroísmo Circular , Clonagem Molecular , Citoplasma/metabolismo , Eletroforese em Gel de Poliacrilamida , Expressão Gênica , Estágios do Ciclo de Vida , Espectrometria de Massas , Dados de Sequência Molecular , Peso Molecular , Plasmodium falciparum/fisiologia , Estrutura Secundária de Proteína , Proteínas de Protozoários/genética , Proteínas de Protozoários/isolamento & purificação , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/isolamento & purificação
12.
J Biol Chem ; 289(12): 8098-105, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24492614

RESUMO

The present study was designed to examine the functional relevance of two heterozygous mutations (H391Y and K422R), observed earlier by us in the Bloom syndrome condition. Cells stably expressing exogenous wild-type or mutant PKM2 (K422R or H391Y) or co-expressing both wild type and mutant (PKM2-K422R or PKM2-H391Y) were assessed for cancer metabolism and tumorigenic potential. Interestingly, cells co-expressing PKM2 and mutant (K422R or H391Y) showed significantly aggressive cancer metabolism as compared with cells expressing either wild-type or mutant PKM2 independently. A similar trend was observed for oxidative endurance, tumorigenic potential, cellular proliferation, and tumor growth. These observations signify the dominant negative nature of mutations. Remarkably, PKM2-H391Y co-expressed cells showed a maximal effect on all the studied parameters. Such a dominant negative impaired function of PKM2 in tumor development is not known; this study demonstrates for the first time the possible predisposition of Bloom syndrome patients with impaired PKM2 activity to cancer and the importance of studying genetic variations in PKM2 in the future to understand their relevance in cancer in general.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Pulmão/patologia , Mutação de Sentido Incorreto , Piruvato Quinase/genética , Animais , Síndrome de Bloom/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Glicólise , Humanos , Pulmão/metabolismo , Neoplasias Pulmonares/metabolismo , Camundongos , Piruvato Quinase/metabolismo , Espécies Reativas de Oxigênio/metabolismo
15.
Mol Pharm ; 12(12): 4247-58, 2015 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-26567518

RESUMO

Multidrug resistance poses a great challenge to cancer treatment. In order to improve the targeting and codelivery of small interfering RNA (siRNA) and doxorubicin, and to overcome multidrug resistance, we conjugated a cholic acid-polyethylenimine polymer with folic acid, forming CA-PEI-FA micelles. CA-PEI-FA exhibited a low critical micelle concentration (80 µM), small average particle size (150 nm), and positive zeta potential (+ 12 mV). They showed high entrapment efficiency for doxorubicin (61.2 ± 1.7%, w/w), forming D-CA-PEI-FA, and for siRNA, forming D-CA-PEI-FA-S. X-ray photoelectron spectroscopic analysis revealed the presence of external FA on D-CA-PEI-FA micelles. About 25% doxorubicin was released within 24 h at pH 7.4, while more than 30% release was observed at pH 5. The presence of FA enhanced micelle antitumor activity. The D-CA-PEI-FA and D-CA-PEI-FA-S micelles inhibited tumor growth in vivo. No significant differences between their in vitro cytotoxic activities or their in vivo antitumor effects were observed, indicating that the siRNA coloading did not significantly increase the antitumor activity. Histological analysis revealed that tumor tissues from mice treated with D-CA-PEI-FA or D-CA-PEI-FA-S showed the lowest cancer cell density and the highest levels of apoptosis and necrosis. Similarly, the livers of these mice exhibited the lowest level of dihydropyrimidine dehydrogenase among all treated groups. The lowest serum vascular endothelial growth factor level (VEGF) (24.4 pg/mL) was observed in mice treated with D-CA-PEI-FA-S micelles using siRNA targeting VEGF. These findings indicated that the developed CA-PEI-FA nanoconjugate has the potential to achieve targeted codelivery of drugs and siRNA.


Assuntos
Adenocarcinoma/tratamento farmacológico , Ácido Cólico/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Doxorrubicina/administração & dosagem , Ácido Fólico/química , Polietilenoimina/química , RNA Interferente Pequeno/administração & dosagem , Adenocarcinoma/metabolismo , Animais , Linhagem Celular Tumoral , Ácido Cólico/química , Neoplasias Colorretais/metabolismo , Doxorrubicina/química , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Ácido Fólico/administração & dosagem , Humanos , Camundongos , Camundongos Nus , Micelas , Nanoconjugados/administração & dosagem , Nanoconjugados/química , Tamanho da Partícula , Polietilenoglicóis/química , Polietilenoimina/administração & dosagem , Fator A de Crescimento do Endotélio Vascular/metabolismo
16.
BMC Cancer ; 14: 438, 2014 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-24929433

RESUMO

BACKGROUND: The global burden from cancer is rising, especially as low-income countries like Bangladesh observe rapid aging. So far, there are no comprehensive descriptions reporting diagnosed cancer group that include hematological malignancies in Bangladesh. METHODS: This was a multi-center hospital-based retrospective descriptive study of over 5000 confirmed hematological cancer cases in between January 2008 to December 2012. Morphological typing was carried out using the "French American British" classification system. RESULTS: A total of 5013 patients aged between 2 to 90 years had been diagnosed with malignant hematological disorders. A 69.2% were males (n=3468) and 30.8% females (n=1545), with a male to female ratio of 2.2:1. The overall median age at diagnosis was 42 years. Acute myeloid leukemia was most frequent (28.3%) with a median age of 35 years, followed by chronic myeloid leukemia with 18.2% (median age 40 years), non-Hodgkin lymphoma (16.9%; median age 48 years), acute lymphoblastic leukemia (14.1%; median age 27 years), multiple myeloma (10.5%; median age 55 years), myelodysplastic syndromes (4.5%; median age 57 years) and Hodgkin's lymphoma (3.9%; median age 36 years). The least common was chronic lymphocytic leukemia (3.7%; median age 60 years). Below the age of 20 years, acute lymphoblastic leukemia was predominant (37.3%), followed by acute myeloid leukemia (34%). Chronic lymphocytic leukemia and multiple myeloma had mostly occurred among older patients, aged 50-over. CONCLUSIONS: For the first time, our study presents the pattern and distribution of diagnosed hematological cancers in Bangladesh. It shows differences in population distributions as compared to other settings with possibly a lower presence of non-Hodgkin lymphoma. There might be under-reporting of affected women. Further studies are necessary on the epidemiology, genetics and potential environmental risk factors within this rapidly aging country.


Assuntos
Neoplasias Hematológicas/classificação , Neoplasias Hematológicas/diagnóstico , Neoplasias Hematológicas/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bangladesh , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
17.
Mol Pharm ; 11(10): 3596-608, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25157890

RESUMO

The objective of this study is to synthesize and evaluate acute toxicity of the bacterial cellulose (BC)/acrylamide (Am) hydrogels as noncytotoxic and biocompatible oral drug delivery vehicles. A novel series of solubilized BC/Am hydrogels were synthesized using a microwave irradiation method. The hydrogels were characterized by Fourier transform infrared spectroscopy (FTIR), swelling ratio, porosity, drug release, and in vitro and in vivo biocompatibility experiments. FTIR spectra revealed that the BC crystallinity and gel fraction decreased as the NaOH concentration increased from 2% to 10% w/v, whereas the optical transparency, pH sensitivity, and porosity were enhanced with increasing alkali concentration. Theophylline was used as a model drug for drug loading and release studies. The percentage of drug released was higher at pH 7.4 compared to pH 1.5. In vitro cytotoxicity and hemolytic tests indicated that the BC/Am hydrogel is noncytotoxic and hemocompatible. Results of acute oral toxicity tests on ICR mice suggested that the hydrogels are nontoxic up to 2000 mg/kg when administered orally, as no toxic response or histopathological changes were observed in comparison to control mice. The results of this study demonstrated that the pH-sensitive smart hydrogel makes it a possible safe carrier for oral drug delivery.


Assuntos
Acrilamida/química , Celulose/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Hidrogel de Polietilenoglicol-Dimetacrilato/efeitos adversos , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Animais , Portadores de Fármacos/efeitos adversos , Sistemas de Liberação de Medicamentos/efeitos adversos , Feminino , Concentração de Íons de Hidrogênio , Camundongos , Camundongos Endogâmicos ICR
18.
Mol Pharm ; 11(11): 4130-42, 2014 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-25252107

RESUMO

Stimuli-responsive bacterial cellulose-g-poly(acrylic acid) hydrogels were investigated for their potential use as an oral delivery system for proteins. These hydrogels were synthesized using electron beam irradiation without any cross-linking agents, thereby eliminating any potential toxic effects associated with cross-linkers. Bovine serum albumin (BSA), a model protein drug, was loaded into the hydrogels, and the release profile in simulated gastrointestinal fluids was investigated. Cumulative release of less than 10% in simulated gastric fluid (SGF) demonstrated the potential of these hydrogels to protect BSA from the acidic environment of the stomach. Subsequent conformational stability analyses of released BSA by SDS-PAGE, circular dichroism, and an esterase activity assay indicated that the structural integrity and bioactivity of BSA was maintained and preserved by the hydrogels. Furthermore, an increase in BSA penetration across intestinal mucosa tissue was observed in an ex vivo penetration experiment. Our fabricated hydrogels exhibited excellent cytocompatibility and showed no sign of toxicity, indicating the safety of these hydrogels for in vivo applications.


Assuntos
Resinas Acrílicas/química , Celulose/química , Sistemas de Liberação de Medicamentos , Hidrogéis/química , Muco/metabolismo , Soroalbumina Bovina/administração & dosagem , Soroalbumina Bovina/química , Adesivos/química , Animais , Bovinos , Dicroísmo Circular , Reagentes de Ligações Cruzadas/metabolismo , Concentração de Íons de Hidrogênio , Masculino , Soluções Oftálmicas/química , Ratos , Ratos Wistar
19.
Behav Brain Funct ; 10: 12, 2014 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-24716619

RESUMO

OBJECTIVE: While Parkinson's disease (PD) has traditionally been described as a movement disorder, there is growing evidence of disruption in emotion information processing associated with the disease. The aim of this study was to investigate whether there are specific electroencephalographic (EEG) characteristics that discriminate PD patients and normal controls during emotion information processing. METHOD: EEG recordings from 14 scalp sites were collected from 20 PD patients and 30 age-matched normal controls. Multimodal (audio-visual) stimuli were presented to evoke specific targeted emotional states such as happiness, sadness, fear, anger, surprise and disgust. Absolute and relative power, frequency and asymmetry measures derived from spectrally analyzed EEGs were subjected to repeated ANOVA measures for group comparisons as well as to discriminate function analysis to examine their utility as classification indices. In addition, subjective ratings were obtained for the used emotional stimuli. RESULTS: Behaviorally, PD patients showed no impairments in emotion recognition as measured by subjective ratings. Compared with normal controls, PD patients evidenced smaller overall relative delta, theta, alpha and beta power, and at bilateral anterior regions smaller absolute theta, alpha, and beta power and higher mean total spectrum frequency across different emotional states. Inter-hemispheric theta, alpha, and beta power asymmetry index differences were noted, with controls exhibiting greater right than left hemisphere activation. Whereas intra-hemispheric alpha power asymmetry reduction was exhibited in patients bilaterally at all regions. Discriminant analysis correctly classified 95.0% of the patients and controls during emotional stimuli. CONCLUSION: These distributed spectral powers in different frequency bands might provide meaningful information about emotional processing in PD patients.


Assuntos
Encéfalo/fisiopatologia , Emoções/fisiologia , Lateralidade Funcional/fisiologia , Doença de Parkinson/fisiopatologia , Idoso , Eletroencefalografia , Medo/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/psicologia , Reconhecimento Psicológico/fisiologia
20.
Nucleic Acids Res ; 40(3): 1174-90, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22006844

RESUMO

We have investigated the DNA-binding nature as well as the function of a putative Alba (Acetylation lowers binding affinity) family protein (PfAlba3) from Plasmodium falciparum. PfAlba3 possesses DNA-binding property like Alba family proteins. PfAlba3 binds to DNA sequence non-specifically at the minor groove and acetylation lowers its DNA-binding affinity. The protein is ubiquitously expressed in all the erythrocytic stages of P. falciparum and it exists predominantly in the acetylated form. PfAlba3 inhibits transcription in vitro by binding to DNA. Plasmodium falciparum Sir2 (PfSir2A), a nuclear localized deacetylase interacts with PfAlba3 and deacetylates the lysine residue of N-terminal peptide of PfAlba3 specific for DNA binding. PfAlba3 is localized with PfSir2A in the periphery of the nucleus. Fluorescence in situ hybridization studies revealed the presence of PfAlba3 in the telomeric and subtelomeric regions. ChIP and ChIP ReChIP analyses further confirmed that PfAlba3 binds to the telomeric and subtelomeric regions as well as to var gene promoter.


Assuntos
Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Plasmodium falciparum , Proteínas de Protozoários/química , Proteínas de Protozoários/metabolismo , Sequência de Aminoácidos , Imunoprecipitação da Cromatina , DNA/química , DNA/metabolismo , Proteínas de Ligação a DNA/análise , Lisina/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Peptídeos/metabolismo , Ligação Proteica , Proteínas de Protozoários/análise , Proteínas de Ligação a RNA/química , Sirtuína 2/metabolismo , Transcrição Gênica
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