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1.
Malays J Pathol ; 45(3): 457-462, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38155386

RESUMO

Hirschsprung's Disease (HD) is a congenital disorder causing severe constipation in infants and children. Suction rectal biopsy (SRB) is the preferred technique for obtaining tissue samples for histopathological evaluation. In low-resource settings like Malaysia, cost-effective diagnostic approaches are necessary, making single sample SRB valuable. This study evaluates the diagnostic accuracy and sufficiency of a single macroscopically adequate sample in suction rectal biopsies for the histopathological confirmation of HD. We conducted a retrospective study of children who underwent suction rectal biopsies for the diagnosis of HD at Hospital Raja Perempuan Zainab II (HRPZII), Kota Bharu, Kelantan. A total of 68 patients were included in the study. The inadequacy rate for bedside SRB was 14%, comparable to current literature. Our study found no statistically significant association between sample inadequacy and gestational age, gender, birth weight, or weight at biopsy. Complication rates were 0%, consistent with literature reports. Calretinin staining, an additional technique, was performed in 23 biopsy episodes, with a 4.3% inadequacy rate, compared to 20% in specimens not subjected to calretinin staining. The cost of SRB almost doubled with each additional sample taken, significant in low-resource environments. In conclusion, single sample SRBs can be adequately diagnostic and cost-effective in low-resource settings, providing valuable insights for healthcare facilities in Malaysia and other developing countries. The use of adjunctive techniques such as calretinin staining may improve diagnostic accuracy while maintaining cost-effectiveness. Further prospective studies with larger sample sizes are needed to validate these findings.


Assuntos
Doença de Hirschsprung , Lactente , Criança , Humanos , Doença de Hirschsprung/diagnóstico , Doença de Hirschsprung/patologia , Reto/patologia , Calbindina 2 , Estudos Retrospectivos , Sucção , Estudos Prospectivos , Biópsia/métodos
2.
Nat Prod Rep ; 38(4): 682-692, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33021616

RESUMO

Covering: 1951 to 2020Andrographolide is one of the most widely studied plant secondary metabolites, known to display diverse pharmacological actions. Current literature has documented a sizeable list of pharmacological targets for andrographolide, suggesting its multi-targeting nature. Many of these targets are central to the pathophysiology of highly prevalent diseases such as cardiovascular diseases, neurodegenerative disorders, autoimmunity, and even cancer. Despite its well-documented therapeutic efficacy in various disease models, for years, the discrepancies between in vivo bioavailability and bioactivity of andrographolide and the debate surrounding its multi-targeting properties (polypharmacology or promiscuity?) have hindered the development of this versatile molecule into a potential therapeutic agent. Is andrographolide a valuable lead for therapeutic development or a potential invalid metabolic panacea (IMP)? This perspective article aims to discuss this by considering various contributing factors to the polypharmacology of andrographolide.


Assuntos
Diterpenos/farmacologia , Animais , Diterpenos/química , Diterpenos/metabolismo , Diterpenos/farmacocinética , Humanos , Polifarmacologia , Ratos
3.
Pharmacol Res ; 161: 105223, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33017650

RESUMO

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death globally. Cumulative evidence has implicated renin-angiotensin system (RAS) in the pathogenesis of COPD. This study aimed to investigate potential protective effects of angiotensin II type-2 receptor (AT2R) activation in cigarette smoke (CS)-induced COPD models. Compound 21 (C21), a selective and potent non-peptide small molecule AT2R agonist, was evaluated for anti-inflammatory, anti-oxidative and anti-remodeling activities in a two-week (acute) and an eight-week (chronic) CS-induced COPD models. C21 inhibited CS-induced increases in macrophage and neutrophil counts, pro-inflammatory cytokines and oxidative damage markers in bronchoalveolar lavage (BAL) fluid, and TGF-ß1 in lung tissues, from COPD models. C21 restored phosphatase activities and reduced phospho-p38 MAPK, phospho-ERK and p65 subunit of NF-κB levels in CS-exposed lung tissues. C21 also suppressed CS-induced increases in α-Sma, Mmp9, Mmp12 and hydroxyproline levels in lung tissues, and neutrophil elastase activity in BAL fluid. C21 modulated RAS in CS-exposed lungs by downregulating Ang II but upregulating Ang-(1-7) and Mas receptor levels. C21 prevented CS-induced emphysema and improved lung functions in chronic COPD model. We report here for the first time the protective effects of AT2R agonist C21 against CS-induced COPD, and provide strong evidence for further development of AT2R agonist for the treatment of COPD.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Imidazóis/farmacologia , Pulmão/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/prevenção & controle , Enfisema Pulmonar/prevenção & controle , Receptor Tipo 2 de Angiotensina/agonistas , Sistema Renina-Angiotensina/efeitos dos fármacos , Sulfonamidas/farmacologia , Tiofenos/farmacologia , Remodelação das Vias Aéreas/efeitos dos fármacos , Angiotensina I/metabolismo , Angiotensina II/metabolismo , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Mediadores da Inflamação/metabolismo , Pulmão/metabolismo , Pulmão/fisiopatologia , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/metabolismo , Camundongos Endogâmicos BALB C , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fragmentos de Peptídeos/metabolismo , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas , Doença Pulmonar Obstrutiva Crônica/etiologia , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Enfisema Pulmonar/etiologia , Enfisema Pulmonar/metabolismo , Enfisema Pulmonar/fisiopatologia , Receptor Tipo 2 de Angiotensina/metabolismo , Receptores Acoplados a Proteínas G , Transdução de Sinais , Fumaça , Produtos do Tabaco
4.
Br J Pharmacol ; 177(16): 3662-3673, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32335896

RESUMO

BACKGROUND AND PURPOSE: Corticosteroid resistance poses a major barrier to an effective anti-inflammatory therapy for chronic obstructive pulmonary disease (COPD). The present study aimed to investigate potential corticosteroid re-sensitization actions of andrographolide, a bioactive molecule from the herb Andrographis paniculata, in COPD models, particularly in peripheral blood mononuclear cells (PBMCs) from COPD patients. EXPERIMENTAL APPROACH: Corticosteroid sensitivity in PBMCs collected from COPD patients, or in human monocytic U937 cells exposed to cigarette smoke extract (CSE), was determined by measuring LPS-induced IL-8 production, in the presence and absence of andrographolide. The mechanisms of corticosteroid re-sensitization action of andrographolide were evaluated in a mouse cigarette smoke (CS)-induced acute lung injury model. KEY RESULTS: Impaired inhibition of IL-8 production by dexamethasone was detected in PBMCs from COPD patients and in CSE-exposed U937 cells, together with reduced levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and histone deacetylase-2 (HDAC2). In both PBMCs and CSE-exposed U937 cells, andrographolide restored dexamethasone inhibition of IL-8 production, accompanied by the up-regulation of Nrf2 and HDAC2 levels. In the U937 cells, andrographolide was able to block CSE-induced Akt and reduce the level of c-Jun. Besides, andrographolide also augmented dexamethasone actions on lowering total and neutrophil counts, cytokine levels, and oxidative damage markers in bronchoalveolar lavage fluid from CS-exposed mice. CONCLUSION AND IMPLICATIONS: We report here for the first time a novel corticosteroid re-sensitization property of andrographolide in human PBMCs and provide mechanistic evidence to support clinical evaluation of andrographolide in reversing steroid resistance in COPD.


Assuntos
Fator 2 Relacionado a NF-E2 , Doença Pulmonar Obstrutiva Crônica , Corticosteroides , Animais , Diterpenos , Histona Desacetilase 2 , Humanos , Leucócitos Mononucleares , Camundongos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico
5.
Pharmacol Res ; 144: 1-7, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30953685

RESUMO

Autophagy is an evolutionary conserved process that is responsible for maintaining cellular homeostasis through lysosome-dependent degradation of damaged proteins, lipid and organelles. When autophagy is dysregulated by factors such as cigarette smoking, environmental insults and ageing, it can lead to formation of aggresome-bodies and enhanced production of reactive oxygen species (ROS), of which contribute to the pathogenesis of chronic obstructive pulmonary disease (COPD). This review will aim to decipher the pathogenic process of autophagy that is dysregulated by the various risk factors of COPD, leading to either cell death or senescence and COPD progression. It will also cover potential therapeutics that can be used to augment autophagy for the treatment of COPD. This will help shed light on COPD pathophysiology in the context of autophagy so that novel therapeutics can be developed to provide target-specific treatment.


Assuntos
Autofagia , Doença Pulmonar Obstrutiva Crônica/patologia , Animais , Autofagia/efeitos dos fármacos , Humanos , Mitofagia/efeitos dos fármacos , Terapia de Alvo Molecular , Estresse Oxidativo/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/etiologia , Doença Pulmonar Obstrutiva Crônica/metabolismo , Fatores de Risco
6.
J Intern Med ; 285(4): 436-445, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30521125

RESUMO

BACKGROUND: A lack of consensus exists amongst national guidelines regarding who should be investigated for haematuria. Type of haematuria and age-specific thresholds are frequently used to guide referral for the investigation of haematuria. OBJECTIVES: To develop and externally validate the haematuria cancer risk score (HCRS) to improve patient selection for the investigation of haematuria. METHODS: Development cohort comprise of 3539 prospectively recruited patients recruited at 40 UK hospitals (DETECT 1; ClinicalTrials.gov: NCT02676180) and validation cohort comprise of 656 Swiss patients. All patients were aged >18 years and referred to hospital for the evaluation of visible and nonvisible haematuria. Sensitivity and specificity of the HCRS in the validation cohort were derived from a cut-off identified from the discovery cohort. RESULTS: Patient age, gender, type of haematuria and smoking history were used to develop the HCRS. HCRS validation achieves good discrimination (AUC 0.835; 95% CI: 0.789-0.880) and calibration (calibration slope = 1.215) with no significant overfitting (P = 0.151). The HCRS detected 11.4% (n = 8) more cancers which would be missed by UK National Institute for Health and Clinical Excellence guidelines. The American Urological Association guidelines would identify all cancers with a specificity of 12.6% compared to 30.5% achieved by the HCRS. All patients with upper tract cancers would have been identified. CONCLUSION: The HCRS offers good discriminatory accuracy which is superior to existing guidelines. The simplicity of the model would facilitate adoption and improve patient and physician decision-making.


Assuntos
Hematúria/etiologia , Medição de Risco , Neoplasias da Bexiga Urinária/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Medição de Risco/métodos , Fatores de Risco , Sensibilidade e Especificidade , Fumar/efeitos adversos , Neoplasias da Bexiga Urinária/complicações , Neoplasias da Bexiga Urinária/etiologia , Adulto Jovem
7.
Toxicol Appl Pharmacol ; 360: 120-130, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30291937

RESUMO

Cigarette smoking is the leading cause of chronic obstructive pulmonary disease (COPD). Cigarette smoke heightens oxidative stress and impairs autophagy, advancing COPD progression. Andrographolide is a bioactive diterpenoid lactone isolated from the plant Andrographis paniculata which has been a traditional medicinal herb for respiratory diseases. As airway epithelial cells form the first interface to be exposed to cigarette smoke, this study aimed to explore the modulatory effects of andrographolide on oxidative stress and autophagy in human bronchial epithelial BEAS-2B cells exposed to cigarette smoke extract (CSE). CSE (2%) exposure increased autophagic markers p62 and LC3B-II levels in BEAS-2B cells. Andrographolide alone increased p62 and p-p62 (S349) but not LC3B-II in BEAS-2B cells. However, in the presence of CSE, andrographolide was able to simultaneously increase LC3B-II level and enhance antioxidant defense by decreasing oxidative stress and increasing total antioxidant capacity, through upregulation of nuclear Nrf2 via the p62-Nrf2 positive feedback loop. Using RFP-GFP-LC3B transfected BEAS-2B cells exposed to CSE, andrographolide was found to impair autophagosome fusion with lysosome, which may account for the moderate increase in activated caspase 3/7 and annexin V levels. Our findings revealed for the first time that andrographolide simultaneously upregulated antioxidant defense through the p62-Nrf2 loop and moderately induced apoptosis through impairment of autophagic flux in CSE-exposed bronchial epithelium. Andrographolide facilitated cigarette smoke-induced apoptosis may be a potential toxicological outcome or may protect against chronic inflammation and aberrant DNA repair. Validation of these in-vitro findings in an experimental COPD model by andrographolide is warranted.


Assuntos
Antioxidantes/metabolismo , Autofagia/efeitos dos fármacos , Brônquios/efeitos dos fármacos , Diterpenos/farmacologia , Células Epiteliais/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Fumaça/efeitos adversos , Apoptose/efeitos dos fármacos , Brônquios/metabolismo , Linhagem Celular , Células Epiteliais/metabolismo , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/metabolismo , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/metabolismo , Fumar/efeitos adversos , Nicotiana/efeitos adversos , Regulação para Cima/efeitos dos fármacos
8.
Mol Ther Nucleic Acids ; 12: 370-380, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-30195775

RESUMO

Chronic obstructive pulmonary disease (COPD) is estimated to be the third leading cause of death by 2030. Transcription factor NF-κB may play a critical role in COPD pathogenesis. Ribosomal protein S3 (RPS3), a 40S ribosomal protein essential for executing protein translation, has recently been found to interact with the NF-κB p65 subunit and promote p65 DNA-binding activity. We sought to study whether RPS3 gene silencing could protect against cigarette-smoke (CS)-induced acute lung injury in a mouse model. Effects of an intratracheal RPS3 siRNA in CS-induced lung injury were determined by measuring bronchoalveolar lavage (BAL) fluid cell counts, levels of inflammatory and oxidative damage markers, and NF-κB translocation. Lung RPS3 level was found to be upregulated for the first time with CS exposure, and RPS3 siRNA blocked CS-induced neutrophil counts in BAL fluid. RPS3 siRNA suppressed CS-induced lung inflammatory mediator and oxidative damage marker levels, as well as nuclear p65 accumulation and transcriptional activation. RPS3 siRNA was able to disrupt CS extract (CSE)-induced NF-κB activation in an NF-κB reporter gene assay. We report for the first time that RPS3 gene silencing ameliorated CS-induced acute lung injury, probably via interruption of the NF-κB activity, postulating that RPS3 is a novel therapeutic target for COPD.

9.
BMC Palliat Care ; 17(1): 11, 2018 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-29298714

RESUMO

BACKGROUND: Around the world, different models of paediatric palliative care have responded to the unique needs of children with life shortening conditions. However, research confirming their utility and impact is still lacking. This study compared patient-related outcomes and healthcare expenditures between those who received home-based paediatric palliative care and standard care. The quality of life and caregiver burden for patients receiving home-based paediatric palliative care were also tracked over the first year of enrolment to evaluate the service's longitudinal impact. METHOD: A structured impact and cost evaluation of Singapore-based HCA Hospice Care's Star PALS (Paediatric Advance Life Support) programme was conducted over a three-year period, employing both retrospective and prospective designs with two patient groups. RESULTS: Compared to the control group (n = 67), patients receiving home-based paediatric palliative care (n = 71) spent more time at home than in hospital in the last year of life by 52 days (OR = 52.30, 95% CI: 25.44-79.17) with at least two fewer hospital admissions (OR = 2.46, 95% CI: 0.43-4.48); and were five times more likely to have an advance care plan formulated (OR = 5.51, 95% CI: 1.55-19.67). Medical costs incurred by this group were also considerably lower (by up to 87%). Moreover, both patients' quality of life (in terms of pain and emotion), and caregiver burden showed improvement within the first year of enrolment into the programme. DISCUSSION: Our findings suggest that home-based paediatric palliative care brings improved resource utilization and cost-savings for both patients and healthcare providers. More importantly, the lives of patients and their caregivers have improved, with terminally ill children and their caregivers being able to spend more quality time at home at the final stretch of the disease. CONCLUSIONS: The benefits of a community paediatric palliative care programme have been validated. Study findings can become key drivers when engaging service commissioners or even policy makers in appropriate settings.


Assuntos
Custos de Cuidados de Saúde/estatística & dados numéricos , Cuidados Paliativos/normas , Avaliação de Resultados da Assistência ao Paciente , Pediatria/normas , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Serviços de Assistência Domiciliar/organização & administração , Humanos , Lactente , Masculino , Estudos Prospectivos , Qualidade de Vida/psicologia , Estudos Retrospectivos , Singapura
10.
Free Radic Biol Med ; 110: 332-344, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28684161

RESUMO

Inflammation and oxidative stress contribute to emphysema in COPD. Although corticosteroids are the standard of care for COPD, they do not reduce oxidative stress, and a subset of patients is steroid-resistant. Vitamin E isoform γ-tocotrienol possesses both anti-inflammatory and anti-oxidative properties that may protect against emphysema. We aimed to establish the therapeutic potential of γ-tocotrienol in cigarette smoke-induced COPD models in comparison with prednisolone. BALB/c mice were exposed to cigarette smoke for 2 weeks or 2 months. γ-Tocotrienol and prednisolone were given orally. Bronchoalveolar lavage (BAL) fluid and lung tissues were assessed for inflammation, oxidative damage, and regulation of transcription factor activities. Emphysema and lung function were also evaluated. γ-Tocotrienol dose-dependently reduced cigarette smoke-induced BAL fluid neutrophil counts and levels of cytokines, chemokines and oxidative damage biomarkers, and pulmonary pro-inflammatory and pro-oxidant gene expression, but restored lung endogenous antioxidant activities. γ-Tocotrienol acted by inhibiting nuclear translocation of STAT3 and NF-κB, and up-regulating Nrf2 activation in the lungs. In mice exposed to 2-month cigarette smoke, γ-tocotrienol ameliorated bronchial epithelium thickening and destruction of alveolar sacs in lungs, and improved lung functions. In comparison with prednisolone, γ-tocotrienol demonstrated better anti-oxidative efficacy, and protection against emphysema and lung function in COPD. We revealed for the first time the anti-inflammatory and antioxidant efficacies of γ-tocotrienol in cigarette smoke-induced COPD models. In addition, γ-tocotrienol was able to attenuate emphysematous lesions and improve lung function in COPD. γ-Tocotrienol may have therapeutic potential for the treatment of COPD.


Assuntos
Anti-Inflamatórios/farmacologia , Nicotiana/efeitos adversos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Enfisema Pulmonar/prevenção & controle , Espécies Reativas de Oxigênio/antagonistas & inibidores , Fumaça/efeitos adversos , Tocotrienóis/farmacologia , Animais , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Movimento Celular/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/genética , NF-kappa B/metabolismo , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos , Prednisolona/farmacologia , Doença Pulmonar Obstrutiva Crônica/etiologia , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/patologia , Enfisema Pulmonar/etiologia , Enfisema Pulmonar/genética , Enfisema Pulmonar/patologia , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais
11.
J Immunol ; 199(1): 39-47, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28526682

RESUMO

Exposure to environmental allergens is a major risk factor for asthma development. Allergens possess proteolytic activity that is capable of disrupting the airway epithelium. Although there is increasing evidence pointing to asthma as an epithelial disease, the underlying mechanism that drives asthma has not been fully elucidated. In this study, we investigated the direct DNA damage potential of aeroallergens on human bronchial epithelial cells and elucidated the mechanisms mediating the damage. Human bronchial epithelial cells, BEAS-2B, directly exposed to house dust mites (HDM) resulted in enhanced DNA damage, as measured by the CometChip and the staining of DNA double-strand break marker, γH2AX. HDM stimulated cellular reactive oxygen species production, increased mitochondrial oxidative stress, and promoted nitrosative stress. Notably, expression of nuclear factor erythroid 2-related factor 2-dependent antioxidant genes was reduced immediately after HDM exposure, suggesting that HDM altered antioxidant responses. HDM exposure also reduced cell proliferation and induced cell death. Importantly, HDM-induced DNA damage can be prevented by the antioxidants glutathione and catalase, suggesting that HDM-induced reactive oxygen and nitrogen species can be neutralized by antioxidants. Mechanistic studies revealed that HDM-induced cellular injury is NADPH oxidase (NOX)-dependent, and apocynin, a NOX inhibitor, protected cells from double-strand breaks induced by HDM. Our results show that direct exposure of bronchial epithelial cells to HDM leads to the production of reactive oxygen and nitrogen species that damage DNA and induce cytotoxicity. Antioxidants and NOX inhibitors can prevent HDM-induced DNA damage, revealing a novel role for antioxidants and NOX inhibitors in mitigating allergic airway disease.


Assuntos
Alérgenos/imunologia , Antioxidantes/fisiologia , Brônquios/imunologia , Dano ao DNA , Células Epiteliais/imunologia , Pyroglyphidae/imunologia , Espécies Reativas de Oxigênio/metabolismo , Acetofenonas/imunologia , Acetofenonas/farmacologia , Ar , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Fator de Indução de Apoptose/genética , Fator de Indução de Apoptose/metabolismo , Asma/etiologia , Asma/imunologia , Asma/fisiopatologia , Brônquios/citologia , Brônquios/metabolismo , Catalase/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/metabolismo , Glutationa/farmacologia , Humanos , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , NADPH Oxidase 2 , NADPH Oxidase 4 , NADPH Oxidases/genética , NADPH Oxidases/metabolismo
12.
J Nat Prod ; 79(5): 1308-15, 2016 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-27104764

RESUMO

Cigarette smoke (CS) is associated with many maladies, one of which is chronic obstructive pulmonary disease (COPD). As the disease progresses, patients are more prone to develop COPD exacerbation episodes by bacterial infection, particularly to nontypeable Haemophilus influenza (NTHi) infection. The present study aimed to develop a CS-exposed mouse model that increases inflammation induced by NTHi challenge and investigate the protective effects of andrographolide, a bioactive molecule with anti-inflammatory and antioxidant properties isolated from the plant Andrographis paniculata. Female BALB/c mice exposed to 2 weeks of CS followed by a single intratracheal instillation of NTHi developed increased macrophage and neutrophil pulmonary infiltration, augmented cytokine levels, and heightened oxidative damage. Andrographolide effectively reduced lung cellular infiltrates and decreased lung levels of TNF-α, IL-1ß, CXCL1/KC, 8-OHdG, matrix metalloproteinase-8 (MMP-8), and MMP-9. The protective actions of andrographolide on CS-predisposed NTHi inflammation might be attributable to increased nuclear factor erythroid-2-related factor 2 (Nrf2) activation and decreased Kelch-like ECH-associated protein 1 (Keap1) repressor function, resulting in enhanced gene expression of antioxidant enzymes including heme oxygenase-1 (HO-1), glutathione reductase (GR), glutathione peroxidase-2 (GPx-2), glutamate-cysteine ligase modifier (GCLM), and NAD(P)H quinone oxidoreductase 1 (NQO1). Taken together, these findings strongly support a therapeutic potential for andrographolide in preventing lung inflammation caused by NTHi in cigarette smokers.


Assuntos
Andrographis/química , Diterpenos/farmacologia , Haemophilus influenzae/efeitos dos fármacos , Nicotiana/efeitos adversos , Plantas Medicinais/química , Fumar/efeitos adversos , Animais , Diterpenos/química , Feminino , Glutamato-Cisteína Ligase/metabolismo , Infecções por Haemophilus/tratamento farmacológico , Heme Oxigenase-1/metabolismo , Humanos , Metaloproteinase 8 da Matriz/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Estrutura Molecular , Infiltração de Neutrófilos , Neutrófilos/metabolismo , Pneumonia/prevenção & controle , Doença Pulmonar Obstrutiva Crônica/patologia , Fator de Necrose Tumoral alfa/metabolismo
13.
Int J Colorectal Dis ; 31(2): 235-45, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26490055

RESUMO

BACKGROUND: Stage IV colorectal cancer patients with unresectable metastasis who undergo elective primary tumour resection experience heterogeneous post-operative survival. We aimed to develop a scoring model for predicting post-operative survival using pre-operative variables to identify patients who are least likely to experience extended survival following the procedure. METHODS: Survival data were collected from stage IV colorectal cancer patients who had undergone elective primary tumour resection between January 1999 and December 2007. Coefficients of significant covariates from the multivariate Cox regression model were used to compute individual survival scores to classify patients into three prognostic groups. A survival function was derived for each group via Kaplan-Meier estimation. Internal validation was performed. RESULTS: Advanced age (hazard ratio, HR 1.43 (1.16-1.78)); poorly differentiated tumour (HR 2.72 (1.49-5.04)); metastasis to liver (HR 1.76 (1.33-2.33)), lung (HR 1.37 (1.10-1.71)) and bone (HR 2.08 ((1.16-3.71)); carcinomatosis (HR 1.68 (1.30-2.16)); hypoalbuminaemia (HR 1.30 (1.04-1.61) and elevated carcinoembryonic antigen levels (HR 1.89 (1.49-2.39)) significantly shorten post-operative survival. The scoring model separated patients into three prognostic groups with distinct median survival lengths of 4.8, 12.4 and 18.6 months (p < 0.0001). Internal validation revealed a concordance probability estimate of 0.65 and a time-dependent area under receiver operating curve of 0.75 at 6 months. Temporal split-sample validation implied good local generalizability to future patient populations (p < 0.0001). CONCLUSION: Predicting survival following elective primary tumour resection using pre-operative variables has been demonstrated with the scoring model developed. Model-based survival prognostication can support clinical decisions on elective primary tumour resection eligibility.


Assuntos
Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Modelos de Riscos Proporcionais , Idoso , Algoritmos , Antígeno Carcinoembrionário/sangue , Neoplasias Colorretais/sangue , Estudos de Viabilidade , Feminino , Hemoglobinas/metabolismo , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Albumina Sérica/metabolismo
14.
Pharmacol Ther ; 162: 152-69, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26706242

RESUMO

The discovery of vitamin E (α-tocopherol) began in 1922 as a vital component required in reproduction. Today, there are eight naturally occurring vitamin E isoforms, namely α-, ß-, γ- and δ-tocopherol and α-, ß-, γ- and δ-tocotrienol. Vitamin E is potent antioxidants, capable of neutralizing free radicals directly by donating hydrogen from its chromanol ring. α-Tocopherol is regarded the dominant form in vitamin E as the α-tocopherol transfer protein in the liver binds mainly α-tocopherol, thus preventing its degradation. That contributed to the oversight of tocotrienols and resulted in less than 3% of all vitamin E publications studying tocotrienols. Nevertheless, tocotrienols have been shown to possess superior antioxidant and anti-inflammatory properties over α-tocopherol. In particular, inhibition of 3-hydroxy-3-methylglutaryl-coenzyme A reductase to lower cholesterol, attenuating inflammation via downregulation of transcription factor NF-κB activation, and potent radioprotectant against radiation damage are some properties unique to tocotrienols, not tocopherols. Aside from cancer, vitamin E has also been shown protective in bone, cardiovascular, eye, nephrological and neurological diseases. In light of the different pharmacological properties of tocopherols and tocotrienols, it becomes critical to specify which vitamin E isoform(s) are being studied in any future vitamin E publications. This review provides an update on vitamin E therapeutic potentials, protective effects and modes of action beyond cancer, with comparison of tocopherols against tocotrienols. With the concerted efforts in synthesizing novel vitamin E analogs and clinical pharmacology of vitamin E, it is likely that certain vitamin E isoform(s) will be therapeutic agents against human diseases besides cancer.


Assuntos
Vitamina E/análogos & derivados , Vitamina E/uso terapêutico , Animais , Antioxidantes/farmacocinética , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Disponibilidade Biológica , Humanos , Neoplasias , Vitamina E/farmacocinética , Vitamina E/farmacologia
15.
Phytomedicine ; 21(12): 1638-44, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25442271

RESUMO

Cigarette smoking is the primary cause of chronic obstructive pulmonary disease (COPD), which is mediated by lung infiltration with inflammatory cells, enhanced oxidative stress, and tissue destruction. Anti-malarial drug artesunate has been shown to possess anti-inflammatory and anti-oxidative actions in mouse asthma models. We hypothesized that artesunate can protect against cigarette smoke-induced acute lung injury via its anti-inflammatory and anti-oxidative properties. Artesunate was given by oral gavage to BALB/c mice daily 2h before 4% cigarette smoke exposure for 1h over five consecutive days. Bronchoalveolar lavage (BAL) fluid and lungs were collected for analyses of cytokines, oxidative damage and antioxidant activities. Bronchial epithelial cell BEAS-2B was exposed to cigarette smoke extract (CSE) and used to study the mechanisms of action of artesunate. Artesunate suppressed cigarette smoke-induced increases in BAL fluid total and differential cell counts; levels of IL-1ß, MCP-1, IP-10 and KC; and levels of oxidative biomarkers 8-isoprostane, 8-OHdG and 3-nitrotyrosine in a dose-dependent manner. Artesunate promoted anti-oxidant catalase activity and reduced NADPH oxidase 2 (NOX2) protein level in the lungs from cigarette smoke-exposed mice. In BEAS-2B cells, artesunate suppressed pro-inflammatory PI3K/Akt and p44/42 MAPK signaling pathways, and increased nuclear Nrf2 accumulation in response to CSE. Artesunate possesses anti-inflammatory and anti-oxidative properties against cigarette smoke-induced lung injury, probably via inhibition of PI3K and p42/22 MAPK signaling pathways, augmentation of Nrf2 and catalase activities, and reduction of NOX2 level. Our data suggest that artesunate may have therapeutic potential for treating COPD.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Artemisininas/farmacologia , Nicotiana/efeitos adversos , Fumar/efeitos adversos , Lesão Pulmonar Aguda/induzido quimicamente , Animais , Artesunato , Líquido da Lavagem Broncoalveolar/química , Catalase/metabolismo , Linhagem Celular , Citocinas/metabolismo , Feminino , Humanos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Glicoproteínas de Membrana/metabolismo , Camundongos Endogâmicos BALB C , NADPH Oxidase 2 , NADPH Oxidases/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Transdução de Sinais
16.
Tech Coloproctol ; 18(11): 1023-7, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24925354

RESUMO

BACKGROUND: The aim of this study was to review a consecutive series of patients who had undergone excision of recurrent retrorectal tumours and propose surgical strategies to tackle such recurrences. METHODS: Patients were identified from a prospectively maintained database. Demographic details, preoperative imaging and pathology, intra- and post-operative problems and follow-up details were noted. RESULTS: Fifteen patients (11 females) with a median age of 38 years (range 19-75 years) underwent excision of recurrent retrorectal tumours (13 benign) between 2002 and 2012. The median interval between the first and second surgical procedure was 3.5 years (range 1-19 years). Three patients had surgery performed via the transperineal approach, while 12 patients had resection via the abdominal approach. En bloc resection of adjacent organs was needed in three patients. Major pelvic bleeding occurred in two patients. R0 resection was achieved in all 15 patients, and there have been no subsequent recurrences [median follow-up 73 months (range 12-148 months)]. CONCLUSIONS: Benign recurrent retrorectal tumours can be safely excised usually without sacrifice of adjacent organs, while en bloc resection is needed for malignant tumours.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/normas , Recidiva Local de Neoplasia/cirurgia , Guias de Prática Clínica como Assunto , Neoplasias Retais/cirurgia , Adulto , Idoso , Biópsia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Estudos Prospectivos , Neoplasias Retais/diagnóstico , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto Jovem
19.
Singapore Med J ; 53(1): 46-51, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22252183

RESUMO

INTRODUCTION: With improvements in surgical techniques, instrumentation and perioperative care, Hartmann's procedure is now less frequently performed. Restoration of intestinal continuity after Hartmann's procedure has traditionally been viewed to be technically demanding and associated with significant morbidity and mortality. This is a study of outcomes after the reversal of Hartmann's procedure in an Asian population. METHODS: A prospectively collected database showed that 255 patients had undergone Hartmann's procedure from October 1989 to October 2005. Patients who subsequently underwent Hartmann's reversal were identified and their records reviewed retrospectively. RESULTS: Hartmann's reversal was attempted in 49 patients. The most common indication for Hartmann's procedure was colorectal carcinoma (49.0%). The median interval between resection and reversal was 23 weeks. Reversal was successful in 46 (93.9%) patients, with 79.6% experiencing no intraoperative complications. Failure of reversal was significantly associated with prior radiotherapy to the pelvis (p-value = 0.007). Anastomotic leak rates and re-bleeding rates were both 0.0%. 79.6% of patients made an uneventful recovery with no postoperative complications. There was no significant increase in the complication rate in older patients or patients with higher American Society of Anesthesiologists status. The overall incidence of 30-day morbidity and mortality was 20.4% and 0.0%, respectively. CONCLUSION: In our population, Hartmann's procedure is more commonly performed for colorectal cancer rather than for diverticular disease, resulting in lower rates of stoma reversal. Hartmann's reversal could be performed with acceptable morbidity and minimal mortality, although prior radiotherapy and shorter rectal stump may pose challenges during reversal surgery.


Assuntos
Carcinoma/cirurgia , Neoplasias Colorretais/cirurgia , Enteropatias/cirurgia , Laparoscopia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Anastomose Cirúrgica , Povo Asiático , Carcinoma/etnologia , Colo Sigmoide/cirurgia , Neoplasias Colorretais/etnologia , Feminino , Humanos , Enteropatias/etnologia , Masculino , Pessoa de Meia-Idade , Reto/cirurgia , Reoperação , Reprodutibilidade dos Testes , Estudos Retrospectivos , Singapura , Resultado do Tratamento
20.
J Appl Microbiol ; 112(1): 119-31, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21992228

RESUMO

AIMS: To display a liver-specific ligand on the hepatitis B virus core particles for cell-targeting delivery. METHODS AND RESULTS: A liver cell-binding ligand (preS1) was fused at the N-terminal end of the hepatitis B core antigen (HBcAg), but the fusion protein (preS1His(6) HBcAg) was insoluble in Escherichia coli and did not form virus-like particles (VLPs). A method to display the preS1 on the HBcAg particle was established by incorporating an appropriate molar ratio of the truncated HBcAg (tHBcAg) to the preS1His(6) HBcAg. Gold immunomicroscopy showed that the subunit mixture reassembled into icosahedral particles, displaying the preS1 ligand on the surface of VLPs. Fluorescence microscopy revealed that the preS1 ligand delivered the fluorescein-labelled VLPs into the HepG2 cells efficiently. CONCLUSIONS: Chimeric VLPs containing the insoluble preS1His(6) HBcAg and highly soluble tHBcAg were produced by a novel incorporation method. The preS1 ligand was exposed on the surface of the VLPs and was shown to deliver fluorescein molecules into liver cells. SIGNIFICANCE AND IMPACT OF STUDY: The newly established incorporation method can be used in the development of chimeric VLPs that could serve as potential nanovehicles to target various cells specifically by substituting the preS1 ligand with different cell-specific ligands.


Assuntos
Técnicas Genéticas , Antígenos do Núcleo do Vírus da Hepatite B/genética , Antígenos do Núcleo do Vírus da Hepatite B/metabolismo , Hepatócitos/metabolismo , Ligantes , Proteínas Recombinantes de Fusão/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Células HeLa , Células Hep G2 , Humanos , Transporte Proteico , Proteínas Recombinantes de Fusão/genética
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