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1.
Braz. j. biol ; 81(4): 940-953, Oct.-Dec. 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1153447

RESUMO

Abstract Nowadays food borne illness is most common in people due to their epidemic nature. These diseases affect the human digestive system through bacteria, viruses and parasites. The agents of illness are transmitted in our body through various types of food items, water and uncooked. Pathogens show drastic changes in immunosuppressant people. This review gives general insights to harmful microbial life. Pakistan is a developed country and because of its improper food management, a lot of gastrointestinal problems are noted in many patients. Bacteria are most common agents to spread diarrhoea, villi infection, constipation and dysenteric disease in human and induce the rejection of organ transplant. Enhancement of their lifestyle, properly cooked food should be used and to overcome the outbreak of the diseases.


Resumo Hoje em dia, as doenças transmitidas por alimentos são mais comuns em pessoas devido à sua natureza epidêmica. Essas doenças afetam o sistema digestivo humano por meio de bactérias, vírus e parasitas. Os agentes das doenças são transmitidos em nosso corpo por meio de diversos tipos de alimentos, água e crus. Os patógenos mostram mudanças drásticas em pessoas imunossupressoras. Esta revisão fornece uma visão geral da vida microbiana prejudicial. O Paquistão é um país desenvolvido e, devido ao seu manejo alimentar inadequado, muitos problemas gastrointestinais são observados em muitos pacientes. As bactérias são os agentes mais comuns para espalhar diarreia, infecção de vilosidades, obstipação e doença disentérica em humanos e induzem a rejeição de transplantes de órgãos. Melhoria de seu estilo de vida, alimentos devidamente cozidos devem ser utilizados e para superar o aparecimento de doenças.

2.
Braz J Biol ; 83: e247676, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34669912

RESUMO

Development of insecticides resistance mainly hinge with managements techniques for the control of Jassid, Amrasca biguttutla biguttutla. Five insecticides were applied against field collected and laboratory rared jassid populations during the years of 2017 to 2019 to profile their resistance level against field population of jassid through leaf dip method. Very low resistance level was found in jassid against confidor whereas high level of resistance was observed by pyriproxyfen against other test insecticides. Gradual resistance was observed against diafenthiuron. It is concluded that for the management of Jassid repetition of same insecticide should be avoided. The use of confidor may be reduced to overcome resistance against Jassid.


Assuntos
Hemípteros , Inseticidas , Animais , Resistência a Inseticidas , Inseticidas/farmacologia , Laboratórios
3.
Braz J Biol ; 81(4): 940-953, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33605364

RESUMO

Nowadays food borne illness is most common in people due to their epidemic nature. These diseases affect the human digestive system through bacteria, viruses and parasites. The agents of illness are transmitted in our body through various types of food items, water and uncooked. Pathogens show drastic changes in immunosuppressant people. This review gives general insights to harmful microbial life. Pakistan is a developed country and because of its improper food management, a lot of gastrointestinal problems are noted in many patients. Bacteria are most common agents to spread diarrhoea, villi infection, constipation and dysenteric disease in human and induce the rejection of organ transplant. Enhancement of their lifestyle, properly cooked food should be used and to overcome the outbreak of the diseases.


Assuntos
Doenças Transmitidas por Alimentos , Bactérias , Diarreia , Doenças Transmitidas por Alimentos/epidemiologia , Humanos , Paquistão/epidemiologia
4.
Braz. J. Biol. ; 81(4): 99-103, out.-dez. 2021. graf, tab, ilus
Artigo em Inglês | VETINDEX | ID: vti-31535

RESUMO

Abstract Nowadays food borne illness is most common in people due to their epidemic nature. These diseases affect the human digestive system through bacteria, viruses and parasites. The agents of illness are transmitted in our body through various types of food items, water and uncooked. Pathogens show drastic changes in immunosuppressant people. This review gives general insights to harmful microbial life. Pakistan is a developed country and because of its improper food management, a lot of gastrointestinal problems are noted in many patients. Bacteria are most common agents to spread diarrhoea, villi infection, constipation and dysenteric disease in human and induce the rejection of organ transplant. Enhancement of their lifestyle, properly cooked food should be used and to overcome the outbreak of the diseases.(AU)


Resumo Hoje em dia, as doenças transmitidas por alimentos são mais comuns em pessoas devido à sua natureza epidêmica. Essas doenças afetam o sistema digestivo humano por meio de bactérias, vírus e parasitas. Os agentes das doenças são transmitidos em nosso corpo por meio de diversos tipos de alimentos, água e crus. Os patógenos mostram mudanças drásticas em pessoas imunossupressoras. Esta revisão fornece uma visão geral da vida microbiana prejudicial. O Paquistão é um país desenvolvido e, devido ao seu manejo alimentar inadequado, muitos problemas gastrointestinais são observados em muitos pacientes. As bactérias são os agentes mais comuns para espalhar diarreia, infecção de vilosidades, obstipação e doença disentérica em humanos e induzem a rejeição de transplantes de órgãos. Melhoria de seu estilo de vida, alimentos devidamente cozidos devem ser utilizados e para superar o aparecimento de doenças.(AU)


Assuntos
Parasitologia de Alimentos , Microbiologia de Alimentos , Prevenção de Doenças
5.
Virusdisease ; 28(4): 373-382, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29291228

RESUMO

A viral agent implicated in the mortality of marine ornamental "Similar Damselfish" (Pomacentrus similis Allen, 1991) was isolated and characterized. The virus grew well in marine and freshwater fish cell lines from seabass and snakehead. The virus was sensitive to chloroform, acidic pH (3.0) and heat treatment at 56 °C. Biochemical characterisation indicated that the virus had double stranded DNA genome. Transmission electron microscopic analysis of ultrathin sections of infected cell pellets showed iridovirus-like icosahedral virus particles of 120-130 nm. Purified virus had six structural protein bands that ranged from of 44 to 132 kDa. PCR analysis confirmed the presence of viral DNA in infected cell cultures and sequence analysis of the major capsid protein gene showed an identity of 99.82% to that of largemouth bass virus. Serum neutralization studies involving the viral agent and koi ranavirus (KIRV) indicated partial homogeneity between the two isolates. Experimental infection of seabass (Lates calcarifer) and similar damselfish (P. similis) fingerlings with the similar damselfish virus showed cumulative mortalities of 68.75 and 93.33%. The biophysical and biochemical properties of the viral agent isolated, serological characteristics, size of major capsid proteins and the sequence similarity of the MCP gene proved that the virus belongs to the genus Ranavirus of the family Iridoviridae. Ability of the virus to grow in marine and freshwater fish cell lines and its pathogenicity to one of the cultivable marine fish shows the wide host range of the virus. This is the first report of ranavirus induced mortality in marine fish in India.

6.
Acta Pol Pharm ; 69(5): 871-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23061283

RESUMO

Mixed ligand Cu(II) complexes of the type [M(Q)(L)]-2H2O have been synthesized using 8-hydroxyquinoline (HQ) as a primary ligand and N- and/or O-donor amino acids (HL) such as L-threonine, L-proline, L-hydroxyproline, L-isoleucine and L-serine as secondary ligands. The metal complexes have been characterized on the basis of elemental analysis, electrical conductance, room temperature magnetic susceptibility measurements, spectral and thermal studies. The electrical conductance studies of the complexes in DMSO (dimethyl sulfoxide) in 10(-3) M concentration indicate their non-electrolytic nature. Room temperature magnetic susceptibility measurements revealed paramagnetic nature of the complexes. Electronic absorption spectra of the complexes show intra-ligand, charge transfer transitions and d-d transitions. The thermal analysis data of the complexes indicate the presence of crystallized water molecules. The agar cup method and tube dilution method have been used to study the antibacterial activity of the complexes against the pathogenic bacteria S. aureus, C. diphtheriae, P. aeruginosa and E. coli. The results have been compared with those of tetracycline, which was screened simultaneously and indicated mild antibacterial activity of the complexes.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Cobre/química , Cobre/farmacologia , Ligantes , Testes de Sensibilidade Microbiana
7.
Acta Pol Pharm ; 69(4): 679-86, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22876610

RESUMO

Mixed ligand complexes of dioxouranium(VI) of the type [UO2(Q)(L)-2H2O] have been synthesized using 8-hydroxyquinoline (HQ) as a primary ligand and N- and/or O- donor amino acids (HL) such as L-lysine, L-aspartic acid and L-cysteine as secondary ligands. The metal complexes have been characterized on the basis of elemental analysis, electrical conductance, room temperature magnetic susceptibility measurements, spectral and thermal studies. The electrical conductance studies of the complexes in DMF in 10(-3) M concentration indicate their non-electrolytic nature. Room temperature magnetic susceptibility measurements revealed diamagnetic nature of the complexes. Electronic absorption spectra of the complexes show intra-ligand and charge transfer transitions, respectively. Bonding of the metal ion through N- and O- donor atoms of the ligands is revealed by IR studies and the chemical environment of the protons is also confirmed by NMR studies. The thermal analysis data of the complexes indicate the presence of coordinated water molecules. The agar cup and tube dilution methods have been used to study the antibacterial activity of the complexes against the pathogenic bacteria S. aureus, C. diphtherinae, S. typhi and E. coli.


Assuntos
Aminoácidos/síntese química , Aminoácidos/farmacologia , Antibacterianos/síntese química , Antibacterianos/farmacologia , Óxidos/síntese química , Óxidos/farmacologia , Oxiquinolina/síntese química , Oxiquinolina/farmacologia , Urânio/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Condutividade Elétrica , Ligantes , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Oxiquinolina/análogos & derivados , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Relação Estrutura-Atividade , Temperatura , Água/química
8.
Int Immunopharmacol ; 13(2): 190-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22487127

RESUMO

Histamine is a mediator of inflammation in allergic disease and asthma. Stress activated protein kinases/c-jun N-terminal kinases (SAPK/JNK) are involved in asthma. This study examined the role of histamine receptors on the phosphorylation of SAPK/JNK in splenocytes. C57BL/6 mice splenocytes were treated with histamine (10⁻4 M to 10⁻¹¹ M), and its selective receptor agonists, phorbol 12 myristate 13-acetate (PMA) was used as a positive control, and phosphorylation of SAPK/JNK was determined. Histamine (10⁻4 M-10⁻8 M) inhibited phosphorylation of SAPK/JNK. H1R agonist betahistine (10⁻5 M) decreased SAPK/JNK phosphorylation and H2R agonist amthamine (10⁻5 M) did not show any significant effect. However, H3R agonist methimepip (10⁻6 M) and H4R agonist 4-methyl histamine (10⁻6 M), increased SAPK/JNK phosphorylation. We used TNFα knockout mice to determine if histamine regulated SAPK/JNK phosphorylation via TNFα. While the effects of histamine and H1 agonists were similar to that of wild type mice in inhibiting the phosphorylation of SAPK/JNK, the effects of H3 and H4 agonists differed in TNFα knockout mice splenocytes. Activation of H3 receptors decreased SAPK/JNK phosphorylation in TNFα knockout mice, as opposed to an increase in wild type mice, whereas H4 agonist did not show any significant effect on the phosphorylation of SAPK/JNK. This data showed that histamine acting through H4 receptors caused the phosphorylation of SAPK/JNK via TNFα. The role of H4 receptors in pro-inflammatory response is intriguing.


Assuntos
Sistema de Sinalização das MAP Quinases , Receptores Histamínicos/metabolismo , Animais , beta-Histina/farmacologia , Feminino , Histamina/farmacologia , Agonistas dos Receptores Histamínicos/farmacologia , Antagonistas dos Receptores Histamínicos/farmacologia , Técnicas In Vitro , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Metilistaminas/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação/efeitos dos fármacos , Receptores Acoplados a Proteínas G/metabolismo , Receptores Histamínicos H3/metabolismo , Receptores Histamínicos H4 , Baço/citologia , Baço/efeitos dos fármacos , Baço/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Tiazóis/farmacologia , Fator de Necrose Tumoral alfa/deficiência , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
9.
Acta Pol Pharm ; 69(6): 1087-93, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23285669

RESUMO

Mixed ligand Th(IV) complexes of the type [M(Q)(L)(NO3)2] x 2 H2O have been synthesized using 8-hydroxyquinoline (HQ) as a primary ligand and N- and/or O- donor amino acids (HL) such as L-lysine, L-aspartic acid and L-cysteine as secondary ligands. The metal complexes have been characterized on the basis of elemental analysis, electrical conductance, room temperature magnetic susceptibility measurements,spectral and thermal studies. The electrical conductance studies of the complexes in DMF in 10(-3) M concentration indicate their non-electrolytic nature. Room temperature magnetic susceptibility measurements revealed diamagnetic nature of the complexes. Electronic absorption spectra of the complexes show intra-ligand and charge transfer transitions, respectively. Bonding of the metal ion through N- and O- donor atoms of the ligands revealed by IR studies and the chemical environment of the protons is also confirmed by NMR studies. The thermal analysis data of the complexes indicate the presence of crystallized water molecules. The agar cup and tube dilution method have been used to study the antibacterial activity of the complexes against the pathogenic bacteria S. aureus, C. diphtheriae, S. typhi and E. coli.


Assuntos
Aminoácidos/química , Antibacterianos/síntese química , Oxiquinolina/química , Compostos de Tório/química , Antibacterianos/química , Antibacterianos/farmacologia , Ligantes , Espectroscopia de Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Acta Pol Pharm ; 68(6): 881-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22125953

RESUMO

Mixed ligand Th(IV) complexes of the type [M(Q)(L)(NO3)2] x 2H2O have been synthesized using 8-hydroxyquinoline (HQ) as a primary ligand and N- and/or O- donor amino acids (HL) such as L-threonine, L-tryptophan and L-isoleucine as secondary ligands. The metal complexes have been characterized on the basis of elemental analysis, electrical conductance, room temperature magnetic susceptibility measurements, spectral and thermal studies. The electrical conductance studies of the complexes in DMF in 10(-3). M concentration indicate their non-electrolytic nature. Room temperature magnetic susceptibility measurements revealed diamagnetic nature of the complexes. Electronic absorption spectra of the complexes show intra-ligand and charge transfer transitions, respectively. Bonding of the metal ion through N- and O-donor atoms of the ligands revealed by IR studies and the chemical environment of the protons is also confirmed by NMR studies. The thermal analysis data of the complexes indicate the presence of crystalline water molecules. The tube dilution method has been used to study the antibacterial activity of the complexes against the pathogenic bacteria S. aureus, C. diphtheriae, S. typhi and E. coli.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Nitrogênio/química , Oxigênio/química , Compostos de Tório/síntese química , Compostos de Tório/farmacologia , Aminoácidos/química , Corynebacterium diphtheriae/efeitos dos fármacos , Corynebacterium diphtheriae/crescimento & desenvolvimento , Desenho de Fármacos , Condutividade Elétrica , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Ligantes , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Oxiquinolina/química , Salmonella typhi/efeitos dos fármacos , Salmonella typhi/crescimento & desenvolvimento , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Relação Estrutura-Atividade , Tecnologia Farmacêutica/métodos , Termogravimetria
11.
Immunopharmacol Immunotoxicol ; 33(2): 250-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21554104

RESUMO

Histamine is implicated in allergic disease and asthma and ERK1/2 is involved in allergic inflammation including Th2 differentiation and proliferation. This study was designed to study the effects of histamine on ERK1/2 phosphorylation in splenocytes. C57/BL6 splenocytes were treated with different concentrations of histamine (10(-4) to 10(-11) M). Histamine (10(-4) M) increased ERK2 phosphorylation. There was, however, no significant effect seen at other concentrations (10(-11) to 10(-6) M). Surprisingly, H1 receptor agonist ß-histine (10(-5) M), H2 agonist amthamine (10(-5) M), H3 agonist methimepip (10(-6) M), and H4 agonist 4-methyl histamine (10(-6) M), all increased ERK2 phosphorylation. H1R antagonist pyrilamine (10(-6) M), H2R antagonist ranitidine (10(-5) M), H3/H4R antagonist thioperamide (10(-6) M), and H3R antagonist clobenpropit (10(-5) M) inhibited histamine-mediated ERK2 phosphorylation suggesting that all four histamine receptor subtypes played some role in this phosphorylation. Because tumor necrosis factor-α (TNF-α) causes phosphorylation of ERK1/2, we investigated whether histamine acted via secretion of TNF-α to affect ERK1/2 phosphorylation. As a consequence, TNF-α knockout mice were used and we found that there was inhibition of ERK1 and ERK2 phosphorylation by H2, H3, and H4 agonists. This was in contrast to the wild-type splenocytes where histamine augmented the phosphorylation of ERK2 via H2, H3, and H4 receptors. In TNF-α knockout mice histamine did not affect the phosphorylation of ERK2 via H1 receptors. The results suggested that histamine indirectly caused the ERK2 phosphorylation via its effects on the secretion of TNF-α and these effects were mediated via H1, H2, H3, and H4 receptors.


Assuntos
Histamina/fisiologia , Proteína Quinase 1 Ativada por Mitógeno/fisiologia , Baço/citologia , Baço/fisiologia , Animais , Feminino , Histamina/farmacologia , Agonistas dos Receptores Histamínicos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , Baço/efeitos dos fármacos , Fator de Necrose Tumoral alfa/deficiência
12.
ISRN Pharm ; 2011: 168539, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22389843

RESUMO

Mixed ligand complexes of dioxouranium (VI) of the type [UO(2)(Q)(L)·2H(2)O] have been synthesized using 8-hydroxyquinoline (HQ) as a primary ligand and amino acids (HL) such as L-threonine, L-tryptophan, and L-isoleucine as secondary ligands. The metal complexes have been characterized by elemental analysis, electrical conductance, magnetic susceptibility measurements, and spectral and thermal studies. The electrical conductance studies of the complexes indicate their nonelectrolytic nature. Magnetic susceptibility measurements revealed diamagnetic nature of the complexes. Electronic absorption spectra of the complexes show intraligand and charge transfer transitions, respectively. Bonding of the metal ion through N- and O-donor atoms of the ligands is revealed by IR studies, and the chemical environment of the protons is confirmed by NMR studies. The thermal analysis data of the complexes indicate the presence of coordinated water molecules. The agar cup and tube dilution methods have been used to study the antibacterial activity of the complexes against the pathogenic bacteria S. aureus, C. diphtheriae, S. typhi, and E. coli.

13.
Br J Radiol ; 81(972): e279-81, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19029047

RESUMO

Aspergilloma is a saprophytic infection that colonizes pre-existing lung cavities. Typically, aspergilloma develops in cavities formed as a result of diseases such as tuberculosis, sarcoidosis, bronchiectasis, lung abscess and cavitatory neoplasia. Coexistence of fungi with a pulmonary echinococcal (hydatid) cyst is seen more commonly in immunocompromised patients. Although aspergilloma has occasionally been described in operated hydatid cyst cavities, only one case has been reported previously in an unoperated case. We report on the case of a 40-year-old man with normal immune status and histologically proven concurrent infection of aspergillus in a previously unoperated pulmonary hydatid cyst.


Assuntos
Aspergilose/complicações , Equinococose Pulmonar/complicações , Pneumopatias Fúngicas/complicações , Infecções Oportunistas/complicações , Adulto , Aspergilose/diagnóstico por imagem , Aspergilose/patologia , Equinococose Pulmonar/diagnóstico por imagem , Equinococose Pulmonar/patologia , Humanos , Pneumopatias Fúngicas/diagnóstico por imagem , Pneumopatias Fúngicas/patologia , Masculino , Infecções Oportunistas/diagnóstico por imagem , Infecções Oportunistas/patologia , Tomografia Computadorizada por Raios X
14.
Acta Pol Pharm ; 64(1): 9-15, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17665845

RESUMO

Mixed ligand complexes of dioxouranium(VI) and thorium(IV) in the proportion 1:1:1 and 1:2:1 have been synthesized using 8-hydroxyquinoline as a primary ligand and L-proline and 4-hydroxy-L-proline as secondary ligands, respectively. The metal complexes have been characterized on the basis of elemental analysis, molar conductance, magnetic, spectral and thermal studies. The molar conductance studies of the complexes in DMF at 10(-3) M concentrations indicate their non-electrolytic nature. Room temperature magnetic susceptibility measurements revealed diamagnetic nature of the complexes. Electronic absorption spectra of the complexes show intra-ligand and charge transfer transitions, respectively. The thermal analysis data of the complexes indicates the presence of a coordinated water molecule/molecules. The tube dilution method has been used to study the antibacterial activity of the complexes against the pathogenic bacteria Staphylococcus aureus and Escherichia coli. The results have been compared against those of control tetracycline, which was screened simultaneously. The complexes have been screened for in vitro cytotoxicity (IC50) studies against Ehrlich ascites cells and Dalton's lymphoma ascites cells, respectively.


Assuntos
Antibacterianos/síntese química , Antineoplásicos/síntese química , Óxidos/síntese química , Tório/química , Animais , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Carcinoma de Ehrlich , Linhagem Celular Tumoral , Análise Diferencial Térmica , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Hidroxiprolina/química , Concentração Inibidora 50 , Ligantes , Magnetismo , Óxidos/química , Óxidos/farmacologia , Oxiquinolina/química , Prolina/química , Espectroscopia de Infravermelho com Transformada de Fourier , Tório/farmacologia , Urânio/química , Urânio/farmacologia
15.
Int Immunopharmacol ; 7(3): 277-86, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17276885

RESUMO

Signal Transducer and Activator of Transcription (STAT)-6 is a transcriptional factor activated mainly through the cytokines IL-4 and IL-13 leading to the Th2 cell differentiation. Th2 cells play a role in the etiology and pathogenesis of allergic disease. Histamine alters the Th1/Th2 cytokine balance towards the Th2 cytokine profile and consequently plays a role in allergic diseases and asthma. This study was designed to investigate the effects of histamine on the STAT6 phosphorylation. C57/BL6 splenocytes were pretreated with different concentrations of histamine (10(-)(4) M to 10(-)(13) M) followed by stimulation with PMA+ionomycin or IL-4. The phosphorylated and total basal STAT6 levels were assessed by employing the immunoblotting technique. Histamine caused the hyper-phosphorylation of STAT6. H1 receptor antagonist pyrilamine reversed the effect of histamine on STAT6 phosphorylation. However, H2 receptor antagonist ranitidine and H3/H4 receptor antagonist thioperamide did not affect the histamine mediated hyper-phosphorylation of STAT6. Furthermore, H1 receptor agonist betahistine enhanced the phosphorylation of STAT6 whereas H2 receptor agonist amthamine did not affect the phosphorylation STAT6. Furthermore, tyrosine kinase inhibitor, tyrphostin, inhibited the histamine mediated phosphorylation of STAT6 when stimulated with PMA+ionomycin. The effects of histamine on the STAT6 phosphorylation were indirect since they were blocked either by the antibodies to IL-4 and IL-13 or in IL-4 knock out mice in the presence of IL-13 antibody. These observations suggest that histamine indirectly affected the STAT6 phosphorylation via its effects on the secretion of cytokines (IL-4) and H1 receptor played a role in this process.


Assuntos
Histamina/farmacologia , Interleucina-4/biossíntese , Receptores Histamínicos H1/fisiologia , Fator de Transcrição STAT6/metabolismo , Animais , Feminino , Interleucina-13/fisiologia , Ionomicina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Receptores Histamínicos/fisiologia , Acetato de Tetradecanoilforbol/farmacologia
16.
Int Immunopharmacol ; 6(3): 485-93, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16428084

RESUMO

Histamine shifts TH1/TH2 cytokine balance from TH1 to TH2 cytokines and regulates the function of lymphocytes after binding to histamine receptors. The phosphorylation of STAT factors and the translocation to the nucleus are important steps in the regulation of TH1/TH2 cytokine balance. This study was designed to investigate the effects of histamine on the phosphorylation of STAT4. C57BL/6 splenocytes were isolated and treated with histamine (10(-4) to 10(-9) M) after activation with either PMA (phorbol 12 myristate 13-acetate) plus ionomycin or IL-12. The phosphorylated STAT4 levels were analyzed by Western Blot Analysis. Unstimulated splenocytes expressed both STAT4 and phosphorylated STAT4. However, phosphorylated STAT4 gradually declined within 24 h. Histamine increased the phosphorylation of STAT4 at lower concentrations (10(-6) to 10(-9) M), and had no effect at higher concentrations (10(-4) and 10(-5) M) after the cells were stimulated with PMA + ionomycin. Histamine did not affect IL-12-induced phosphorylation of STAT4. To characterize the histamine receptor subtypes involved in the up-regulation of STAT4 phosphorylation, various H1, H2 and H3/H4 receptor antagonists and/or agonists were employed. H1 receptor agonist (betahistine), but not H2 receptor agonist (amthamine), induced phosphorylation of STAT4. H1 receptor antagonist (pyrilamine) inhibited histamine-mediated phosphorylation of STAT4. However, H2 receptor antagonist (ranitidine) and H3/H4 receptor antagonist (thioperamide) did not alter this effect. Tyrosine kinase inhibitor (tyrphostin) failed to block histamine-mediated phosphorylation of STAT4. These observations suggest that histamine up-regulated the phosphorylation of STAT4 via H1 receptors, and that the Ca2+-PKC pathway, but not the tyrosine kinase pathway, was involved in this effect.


Assuntos
Histamina/fisiologia , Receptores Histamínicos H1/fisiologia , Fator de Transcrição STAT4/metabolismo , Regulação para Cima/fisiologia , Animais , Carcinógenos/farmacologia , Células Cultivadas , Feminino , Agonistas dos Receptores Histamínicos/farmacologia , Antagonistas dos Receptores Histamínicos H1/farmacologia , Interleucina-12/fisiologia , Ionomicina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Baço/citologia , Baço/efeitos dos fármacos , Baço/metabolismo , Acetato de Tetradecanoilforbol/farmacologia
17.
Acta Pol Pharm ; 63(2): 95-100, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17514871

RESUMO

Mixed ligand Th(IV) complexes of the type [M(Q)2LNO3.H2O] have been synthesized using 8-hydroxyquinoline (HQ) as a primary ligand and N- and/or O- donor amino acids (HL) such as L-alanine, L-phenylalanine, L-serine and L-tyrosine as secondary ligands. The metal complexes have been characterized on the basis of elemental analysis, electrical conductance, room temperature magnetic susceptibility measurements, spectral and thermal studies. The electrical conductance studies of the complexes in DMF at 10(-3) M concentration indicate their non-electrolytic nature. Room temperature magnetic susceptibility measurements revealed diamagnetic nature of the complexes. Electronic absorption spectra of the complexes show intra-ligand and charge transfer transitions, respectively. The thermal analysis data of the complexes indicate the presence of a coordinated water molecule. The tube dilution method has been used to study the antibacterial activity of the complexes against the pathogenic bacteria S. aureus and E. coli. The results have been compared against those of control tetracycline, which was screened simultaneously and indicate mild antibacterial activity of the complexes. The representative complex has been screened for cytotoxicity (IC50) studies against Ehrlich ascites cells and Daltons lymphoma ascites cells and shows low cytotoxic activity.


Assuntos
Antibacterianos/síntese química , Antibacterianos/toxicidade , Tório/química , Animais , Antibacterianos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Escherichia coli/efeitos dos fármacos , Ligantes , Modelos Químicos , Estrutura Molecular , Staphylococcus aureus/efeitos dos fármacos , Termodinâmica
18.
Int Immunopharmacol ; 5(7-8): 1299-309, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15914334

RESUMO

Signal transducer and activator of transcription-1 (STAT1) is a latent signal transducer protein which, on phosphorylation, is translocated from the cytoplasm to the nucleus and is subsequently activated. This study was designed to determine the involvement of histamine receptors in histamine-mediated effect on STAT1 phosphorylation. It is known that the actions of histamine mediated through H1 and H2 receptors are dependent on their respective downstream pathways, Ca(2+)-PKC and cAMP-PKA. In this study, we investigated the significance of PKA in STAT1 phosphorylation. C57BL/6 mouse splenocytes were isolated and treated with histamine (10(-7)-10(-4) M) and then activated with PMA (phorbol 12 myristate 13-acetate) plus ionomycin. The phosphorylated STAT1 levels were analyzed by immunoblotting. Histamine receptor agonists amthamine and betahistine, histamine receptor antagonists pyrilamine maleate, tripelennamine, ranitidine, cimetidine and thioperamide, cAMP agonists N(6), 2'-0-dibutyryladenosine-3',5'-cyclic monophosphate sodium salt (db-cAMP) and forskolin, protein kinase A inhibitors N-(2-[p-bromocinnamylamino]ethyl)-5-isoquinoline-sulfonamide (H89) and Rp diastereomer of adenosine cyclic 3',5'-phosphorothioate (RpcAMPs) and tyrosine kinase inhibitor tyrphostin were used to identify the upstream signal transduction pathways. We observed that histamine augmented the phosphorylation of STAT1 through both H1 and H2 receptors. Furthermore, H1 and H2 receptor antagonists displayed inverse agonism. Ca(2+)-PKC-induced phosphorylation of STAT1 was completely inhibited by H89 and significantly inhibited by RpcAMPs. DbcAMP and forskolin augmented the Ca(2+)-PKC-induced STAT1 phosphorylation thus suggesting a convergent crosstalk between the two histamine receptor signaling pathways, PKA and PKC.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Receptores Histamínicos H1/fisiologia , Receptores Histamínicos H2/fisiologia , Transativadores/metabolismo , Animais , Cálcio/metabolismo , AMP Cíclico/fisiologia , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , Feminino , Histamina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Proteína Quinase C/fisiologia , Pirilamina/farmacologia , Fator de Transcrição STAT1 , Tripelenamina/farmacologia
19.
Int Immunopharmacol ; 3(7): 909-20, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12810348

RESUMO

Atopic asthma is a chronic inflammatory disorder of the airways where upon exposure to allergens, the body mounts an immune response. This disease is associated with an increase in the number of Th2 (T helper type 2) cells and Th2 cytokines and a decrease in the number of Th1 (T helper type 1) cells and Th1 cytokines. Histamine plays an important role in the pathogenesis of atopic asthma through differential regulation of T helper lymphocytes. Histamine enhances the secretion of Th2 cytokines such as IL-4 (interleukin-4), IL-5, IL-10 and IL-13 and inhibits the production of Th1 cytokines IL-2 and IFNgamma (interferon-gamma) and monokine IL-12. It has been shown that histamine can modulate the cytokine network through upregulation of PGE(2) (prostaglandin E(2)) and NO (nitric oxide). Histamine also affects cytokine production via H2 receptors and through the activation of PKA (protein kinase A). We have also demonstrated that the Jak-STAT (Janus kinase-signal transducers and activators of transcription) pathway is involved in histamine-mediated regulation of Th2 cytokines IL-5, IL-10, IL-13 and Th1 cytokine IFNgamma. While standard treatment of asthma consists of beta-receptor agonists and inhaled corticosteroids, the elucidation of histamine's control over the cytokine network and the Th1/Th2 balance provides a basis for the potential use of antihistamines in the prevention and treatment of atopic asthma. Several other anti-allergic agents to modulate the Th1/Th2 balance are under current investigation based on this paradigm. These include cytokines, cytokine antagonists, anti-IgE, and vaccinations. As more advances are made in our understanding of histamine and its control over the Th1/Th2 balance, the use of new therapeutic targets such as these will play a prominent role in disease management.


Assuntos
Asma/imunologia , Citocinas/fisiologia , Histamina/metabolismo , Células Th1/imunologia , Células Th2/imunologia , Asma/tratamento farmacológico , Citocinas/antagonistas & inibidores , Citocinas/metabolismo , Antagonistas dos Receptores Histamínicos H1/farmacologia , Antagonistas dos Receptores Histamínicos H1/uso terapêutico , Humanos , Transdução de Sinais , Células Th1/metabolismo , Células Th2/metabolismo
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