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1.
PLoS Pathog ; 16(7): e1008651, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32658914

RESUMO

Type-2 immunity elicits tissue repair and homeostasis, however dysregulated type-2 responses cause aberrant tissue remodelling, as observed in asthma. Severe respiratory viral infections in infancy predispose to later asthma, however, the processes that mediate tissue damage-induced type-2 inflammation and the origins of airway remodelling remain ill-defined. Here, using a preclinical mouse model of viral bronchiolitis, we find that increased epithelial and mesenchymal high-mobility group box 1 (HMGB1) expression is associated with increased numbers of IL-13-producing type-2 innate lymphoid cell (ILC2s) and the expansion of the airway smooth muscle (ASM) layer. Anti-HMGB1 ablated lung ILC2 numbers and ASM growth in vivo, and inhibited ILC2-mediated ASM cell proliferation in a co-culture model. Furthermore, we identified that HMGB1/RAGE (receptor for advanced glycation endproducts) signalling mediates an ILC2-intrinsic IL-13 auto-amplification loop. In summary, therapeutic targeting of the HMGB1/RAGE signalling axis may act as a novel asthma preventative by dampening ILC2-mediated type-2 inflammation and associated ASM remodelling.


Assuntos
Remodelação das Vias Aéreas/imunologia , Proteína HMGB1/imunologia , Inflamação/imunologia , Linfócitos/imunologia , Músculo Liso/imunologia , Animais , Camundongos , Músculo Liso/patologia , Receptor para Produtos Finais de Glicação Avançada/imunologia
2.
Am J Pathol ; 184(6): 1795-806, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24726644

RESUMO

Human metapneumovirus (hMPV) is a leading cause of respiratory tract disease in children and is associated with acute bronchiolitis, pneumonia, and asthma exacerbations, yet the mechanisms by which the host immune response to hMPV is regulated are poorly understood. By using gene-deleted neonatal mice, we examined the contributions of the innate receptor signaling molecules interferon (IFN)-ß promoter stimulator 1 (IPS-1), IFN regulatory factor (IRF) 3, and IRF7. Viral load in the lungs was markedly greater in IPS-1(-/-) > IRF3/7(-/-) > IRF3(-/-), but not IRF7(-/-), mice compared with wild-type mice. IFN-ß and IFN-λ2/3 (IL-28A/B) production was attenuated in the bronchoalveolar lavage fluid in all factor-deficient mice compared with wild-type mice at 1 day after infection, although IFN-λ2/3 was greater in IRF3/7(-/-) mice at 5 days after infection. IRF7(-/-) and IRF3/7(-/-) mice presented with airway eosinophilia, whereas only IRF3/7(-/-) mice developed an exaggerated type 1 and 17 helper T-cell response, characterized by natural killer T-cell and neutrophilic inflammation. Despite having the highest viral load, IPS-1(-/-) mice did not develop a proinflammatory cytokine or granulocytic response to hMPV infection. Our findings demonstrate that IFN-ß, but not IFN-λ2/3, produced via an IPS-1-IRF3 signaling pathway, is important for hMPV clearance. In the absence of a robust type I IFN-α/ß response, targeting the IPS-1 signaling pathway may limit the overexuberant inflammatory response that occurs as a consequence of viral persistence.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/imunologia , Fator Regulador 3 de Interferon/imunologia , Fator Regulador 7 de Interferon/imunologia , Metapneumovirus/imunologia , Infecções por Paramyxoviridae/imunologia , Células Th1/imunologia , Células Th17/imunologia , Doença Aguda , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Humanos , Fator Regulador 3 de Interferon/genética , Fator Regulador 7 de Interferon/genética , Interferons/genética , Interferons/imunologia , Metapneumovirus/genética , Camundongos , Camundongos Knockout , Infecções por Paramyxoviridae/genética , Infecções por Paramyxoviridae/patologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Células Th1/patologia , Células Th17/patologia
3.
Pak J Pharm Sci ; 23(2): 143-8, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20363690

RESUMO

The objective of this study was to observe the drug interaction between levofloxacin and omeprazole using urinary excretion data. Levofloxacin tablet and omeprazole capsule were administered separately as well as in combination in fasting condition with a wash out period of two weeks after each administration. Urine was collected at different time intervals of 0, 0-2, 2-4, 4-8, 8-12, 12-24, 24-36 and 36-48 hr post-dose and analyzed using a validated HPLC with UV detection. Different pharmacokinetic parameters for both drugs were determined using non-compartmental method. The maximum rate of excretion (R(max)) of levofloxacin was not decreased significantly when co-administered with omeprazole (p<0.05). Similarly no significant difference (p = 0.350) was observed for Rmax of omeprazole when co-administered with levofloxacin. Again the fraction of levofloxacin excreted (f(e)/f) was not changed significantly (p = 0.953) due to the co-administration of omeprazole. Similarly fraction of omeprazole excreted (f(e)/f) also remained unaffected (p = 0.672) when co-administered with levofloxacin. No significant change was observed for the area under the rate of excretion versus midpoint of time interval curve from zero to 48 hours (AURC(0-48)) for levofloxacin and omeprazole (p = 0.816 and 0.792 respectively) when administered separately and co-administered with each other. The study clearly revealed that levofloxacin and omeprazole do not undergo any kind of interactions when administered together. So it can be concluded that these two drugs can be prescribed together to achieve optimum therapeutic activity.


Assuntos
Interações Medicamentosas , Levofloxacino , Ofloxacino/farmacocinética , Ofloxacino/urina , Omeprazol/farmacocinética , Omeprazol/urina , Adolescente , Adulto , Feminino , Humanos , Masculino , Fatores de Tempo
4.
Mucosal Immunol ; 13(4): 652-664, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32066837

RESUMO

The type-2 inflammatory response that promotes asthma pathophysiology occurs in the absence of sufficient immunoregulation. Impaired regulatory T cell (Treg) function also predisposes to severe viral bronchiolitis in infancy, a major risk factor for asthma. Hence, we hypothesized that long-lived, aberrantly programmed Tregs causally link viral bronchiolitis with later asthma. Here we found that transient plasmacytoid dendritic cell (pDC) depletion during viral infection in early-life, which causes the expansion of aberrant Tregs, predisposes to allergen-induced or virus-induced asthma in later-life, and is associated with altered airway epithelial cell (AEC) responses and the expansion of impaired, long-lived Tregs. Critically, the adoptive transfer of aberrant Tregs (unlike healthy Tregs) to asthma-susceptible mice failed to prevent the development of viral-induced or allergen-induced asthma. Lack of protection was associated with increased airway epithelial cytoplasmic-HMGB1 (high-mobility group box 1), a pro-type-2 inflammatory alarmin, and granulocytic inflammation. Aberrant Tregs expressed lower levels of CD39, an ectonucleotidase that hydrolyzes extracellular ATP, a known inducer of alarmin release. Using cultured mouse AECs, we identify that healthy Tregs suppress allergen-induced HMGB1 translocation whereas this ability is markedly impaired in aberrant Tregs. Thus, defective Treg programming in infancy has durable consequences that underlie the association between bronchiolitis and subsequent asthma.


Assuntos
Asma/etiologia , Asma/metabolismo , Bronquiolite/etiologia , Bronquiolite/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Alérgenos/imunologia , Animais , Asma/patologia , Biomarcadores , Bronquiolite/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Suscetibilidade a Doenças , Proteína HMGB1/metabolismo , Imunização , Camundongos , Transporte Proteico , Índice de Gravidade de Doença , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
5.
Curr Ther Res Clin Exp ; 69(6): 504-13, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24692824

RESUMO

BACKGROUND: Amoxicillin, a semisynthetic penicillin antibiotic, is widely prescribed in Bangladesh due to its extended spectrum and its rapid and extensive oral absorption with good tolerability. Although a number of generic oral formulations of amoxicillin are available in Bangladesh, a study of the bioequivalence and pharmacokinetic properties of these formulations has not yet been conducted in a Bangladeshi population. OBJECTIVE: The aim of this study was to assess the pharmacokinetic properties and bioequivalence of 2 formulations of amoxicillin 500-mg capsules (test, SK-mox(®); reference, Amoxil-Bencard(®)) using serum data. METHODS: This single-dose, randomized, open-label, 2-period crossover study was conducted in healthy male subjects in compliance with the Declaration of Helsinki and International Conference on Harmonisation guidelines. Subjects were assigned to receive the test or the reference drug as a single-dose, 500-mg capsule under fasting conditions after a 1-week washout period. After oral administration, blood samples were collected and analyzed for amoxicillin concentration using a validated high-performance liquid chromatography method. The pharmacokinetic parameters were determined using a noncompartmental method. The formulations were considered bioequivalent if the natural log-transformed ratios of pharmacokinetic parameters were within the predetermined equivalence range of 80% to 125%, according to the US Food and Drug Administration (FDA) requirement. RESULTS: Twenty-four healthy adult male Bangladeshi volunteers (mean [SD] age, 26.92 [3.37] years; age range, 23-34 years; mean [SD] body mass index, 23.O9 [1.58] kg/m(2)) participated in the study. Using serum data, the values obtained for the test and reference formulations, respectively, were as follows: Cmax, 9.85 (2.73) and 10.63 (2.12) µg/mL; Tmax, 1.29 (0.58) and 1.33 (0.49) hours; and AUC0-12, 27.09 (7.62) and 28.56 (6.30) µg/mL · h(-1). No period, sequence, or formulation effects were observed; however, significant variation was found among subjects with regard to AUC0-12 (P < 0.001), AUC0-∞ (P = 0.002), area under the moment curve (AUMC) from 0 to 12 hours (P < 0.001), and AUMC0-∞ (P = 0.017). All CIs for the parameters measured were within the FDA-accepted limits of 80% to 125%. CONCLUSION: The present study suggests that the test 500-mg amoxicillin capsule was bioequivalent to the reference 500-mg capsule according to the FDA regulatory definition, in this population of healthy adult male Bangladeshi volunteers.

6.
Biol Trace Elem Res ; 148(3): 275-80, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22383079

RESUMO

The purpose of the present study was to evaluate the status of serum trace elements: zinc, copper, manganese, iron, calcium, and magnesium concentrations in obsessive-compulsive disorder patients. Forty-eight obsessive-compulsive disorder patients and 48 healthy volunteers were included in this study. Patients were recruited from Bangabandhu Sheikh Mujib Medical University by random sampling. Serum trace element concentrations were determined using flame atomic absorption spectroscopy (for zinc, copper, iron, calcium, and magnesium) as well as graphite furnace atomic absorption spectroscopy (for manganese). Data were analyzed using independent t test, Pearson's correlation analysis, regression analysis, and ANOVA. Statistical analysis of these data showed a definite pattern of variation among certain elements in patients with obsessive-compulsive disorder compared to controls. In patients' serum, zinc, iron, and magnesium concentrations decreased significantly (p<0.05) compared to the controls. Serum manganese and calcium concentrations were significantly higher (p<0.05) in patients compared to the controls. These data showed a definite imbalance in the interelement relations in obsessive-compulsive disorder patients compared to controls and therefore suggest a disturbance in the element homeostasis.


Assuntos
Cálcio/sangue , Cobre/sangue , Magnésio/sangue , Manganês/sangue , Transtorno Obsessivo-Compulsivo/sangue , Oligoelementos/sangue , Zinco/sangue , Adulto , Feminino , Humanos , Íons/sangue , Masculino , Adulto Jovem
7.
Biol Trace Elem Res ; 140(3): 272-83, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20390377

RESUMO

Drug abuser patients (n=104), age ranging from 19 to 42 years, were randomly recruited to investigate the serum levels of trace elements (Cu, Zn, Fe, and Mg), malondialdehyde (MDA), and immunoglobulin (IgG, IgA, and IgM) before and after clinical intervention. Control group also included 104 healthy individuals. Blood samples were analyzed for determining trace elements, MDA, and immunoglobulin using atomic absorption spectroscopy, Ultraviolet-Visible (UV-VIS) spectroscopy, and turbidimetry method, respectively. For serum level of Zn and Fe, the differences between the groups (before intervention, after intervention, and control) were not significant (p>0.05). However, significant differences were found in serum copper levels between control group, drug abuser patients, and before and after intervention (p<0.05). The concentration of Mg was found to be significantly higher (p=0.007) in drug abuser patients than the controls, and after intervention, the level was restored to control value. A displacement of elemental homeostasis was observed in drug abuser patients compared to control, and it was improved after intervention. An increase in serum concentration of MDA was found in drug abuser patients compared to control subjects (p>0.05) but was not statistically significant. After intervention, the concentration was restored to control value (p>0.05). The serum concentrations of IgA and IgM were found to be significantly higher (p<0.05) in drug abuser patients before intervention than the controls, and the level tended to be restored to control level after clinical intervention. Serum IgG level was found to be lower in drug abuser patients compared to controls and further declined significantly (p<0.05) after intervention. These findings may suggest a possible imbalance in the levels of micronutrients, antioxidants, and immunoglobulin in drug abuser patients, which tend to be restored to control values after detoxification.


Assuntos
Usuários de Drogas , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Inativação Metabólica/fisiologia , Malondialdeído/sangue , Oligoelementos/sangue , Adulto , Cobre/sangue , Feminino , Humanos , Ferro/sangue , Magnésio/sangue , Masculino , Espectrofotometria Atômica , Adulto Jovem , Zinco/sangue
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