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1.
J Microbiol ; 59(4): 435-447, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33630248

RESUMO

Enterotoxigenic Escherichia coli (ETEC) infection is a major cause of death in children under the age of five in developing countries. ETEC (O78:H11:CFA/I:LT+:ST+) mechanism has been studied in detail with either heat labile (LT) or heat stable (ST) toxins using in vitro and in vivo models. However, there is no adequate information on ETEC pathogenesis producing both the toxins (LT, ST) in BALB/c mice model. In this study, female mice have been employed to understand ETEC H10407 infection induced changes in physiology, biochemical and immunological patterns up to seven days post-infection and the antidiarrhoeal effect of Simarouba amara (Aubl.) bark aqueous extract (SAAE) has also been looked into. The results indicate that BALB/c is sensitive to ETEC infection resulting in altered jejunum and ileum histomorphology. Withal, ETEC influenced cAMP, PGE2, and NO production resulting in fluid accumulation with varied Na+, K+, Cl-, and Ca2+ levels. Meanwhile, ETEC subverted expression of IL-1ß, intestine alkaline phosphatase (IAP), and myeloperoxidase (MPO) in jejunum and ileum. Our data also indicate the severity of pathogenesis reduction which might be due to attainment of equilibrium after reaching optimum rate of infection. Nevertheless, degree of pathogenesis was highly significant (p < 0.01) in all the studied parameters. Besides that, SAAE was successful in reducing the infectious diarrhoea by inhibiting ETEC H10407 in intestine (jejunum and ileum), and shedding in feces. SAAE decreased cAMP, PGE2, and fluid accumulation effectively and boosted the functional activity of immune system in jejunum and ileum IAP, MPO, IL-1ß, and nitric oxide.


Assuntos
Diarreia/tratamento farmacológico , Diarreia/microbiologia , Escherichia coli Enterotoxigênica/efeitos dos fármacos , Infecções por Escherichia coli/tratamento farmacológico , Imunomodulação , Compostos Fitoquímicos/farmacologia , Fosfatase Alcalina/análise , Animais , AMP Cíclico/análise , Dinoprostona/análise , Eletrólitos/sangue , Escherichia coli Enterotoxigênica/patogenicidade , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/microbiologia , Fezes/microbiologia , Feminino , Humanos , Íleo/imunologia , Íleo/microbiologia , Íleo/patologia , Interleucina-1beta/análise , Jejuno/imunologia , Jejuno/microbiologia , Jejuno/patologia , Camundongos , Camundongos Endogâmicos BALB C , Nitritos/análise , Fragmentos de Peptídeos/análise , Peroxidase/análise , Casca de Planta/química , Extratos Vegetais/farmacologia , Simarouba/química
2.
Trop Parasitol ; 9(2): 98-107, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31579664

RESUMO

BACKGROUND AND OBJECTIVES: Dysregulated production of inflammatory cytokines might play important role in anemia during malaria infection. The objective of this study was to assess the extent of anemia due to malaria, associated complications, and inflammatory cytokines (tumor necrosis factor alpha [TNF-α], interleukin [IL]-6, and IL-10) across varying anemic intensity during malaria infections. MATERIALS AND METHODS: A hospital-based cross-sectional study was conducted at District Wenlock hospital in Mangaluru city. Samples from 627 patients and 168 healthy controls (HC) were analyzed for level of hemoglobin (Hb), red blood cells (RBCs), and inflammatory cytokines. The blood cell parameters and inflammatory cytokines levels across varying intensity of anemia were analyzed using Kruskal-Wallis test and pair-wise comparison between two groups were by Mann-Whitney U-test. Correlations were calculated by Pearson's and Spearman rank correlations. RESULTS: Compared to HC, Hb, and RBC levels were significantly lower in infected patients. On comparison with mild anemia patients (Hb 8-10.9 g/dL), the levels of TNF-α and IL-6 were significantly elevated, whereas IL-10 levels were lower during severe anemia (SA) (Hb <5 g/dL). In this endemic setting, we found a strong negative association between Hb levels and parasitemia, Hb and TNF-α, and positive relationship with IL-10; anemic patients also had significantly high TNF-α/IL-10 ratios. SA was associated with complications such as acute renal failure (16.0%), jaundice (16.0%), metabolic acidosis (24.0%), hypoglycemia (12.0%), hyperparasitemia (4.0%), and hepatic dysfunction (16.0%). CONCLUSIONS: Contrary to its benign reputation, Plasmodium vivax (Pv) infections can also result in severe malarial anemia (SMA) and its associated severe complications similar to Plasmodium falciparum infections. Dysregulated inflammatory cytokine responses play an important role in the pathogenesis of SMA, especially during Pv infections.

3.
J Genet Eng Biotechnol ; 16(2): 327-334, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30733742

RESUMO

Among different sources of lipases, fungal lipases have continued to attract a wide range of applications. Further, halophilic lipases are highly desirable for biodiesel production due to the need to mitigate environmental pollution caused as result of extensive use of fossil fuels. However, currently, the high production cost limits the industrial application of lipases. In order to address this issue, we have attempted to optimize lipase production by Fusarium solani NFCCL 4084 and using palm oil mill effluent (POME) based medium. The production was optimized using a combinatory approach of Plackett-Burman (PB) design, one factor at a time (OFAT) design and face centred central composite design (FCCCD). The variables (malt extract, (NH4)2SO4, CaCl2, MgSO4, olive oil, peptone, K2HPO4, NaNO3, Tween-80, POME and pH) were analyzed using PB design and the variables with positive contrast coefficient were found to be K2HPO4, NaNO3, Tween-80, POME and pH. The significant variables selected were further analyzed for possible optimum range by using OFAT approach and the findings revealed that K2HPO4, NaNO3, and Tween-80 as the most significant medium components, and thus were further optimized by using FCCCD. The optimum medium yielded a lipase with an activity of 7.8 U/ml, a significant 3.2-fold increase compared to un-optimized medium. The present findings revealed that POME is an alternative and suitable substrate for halophilic lipase production at low cost. Also, it is clearly evident that the combinatory approach employed here proved to be very effective in producing high activity halophilic lipases, in general.

4.
Proc Natl Acad Sci U S A ; 107(38): 16643-8, 2010 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-20823248

RESUMO

Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) family members mediate the adherence of parasite-infected red blood cells (IRBCs) to various host receptors. A previous study has shown that the parasite protein, cytoadherence-linked asexual gene 9 (CLAG9), is also essential for IRBC adherence. However, how CLAG9 influences this process remains unknown. In this study, we show that CLAG9 interacts with VAR2CSA, a PfEMP1 that mediates IRBC adherence to chondroitin 4-sulfate in the placenta. Importantly, our results show that the adherent parasites synthesize CLAG9 at two stages--the early ring and late trophozoite stages. Localization studies revealed that a substantial level of CLAG9 is located mainly at or in close proximity of the IRBC membrane in association with VAR2CSA. Upon treatment of IRBCs with trypsin, a significant amount of CLAG9 (≈150 kDa) was converted into ≈142-kDa polypeptide. Together these data demonstrate that a considerable amount of CLAG9 is embedded in the IRBC membrane such that at least a portion of the polypeptide at either N or C terminus is exposed on the cell surface. In parasites lacking CLAG9, VAR2CSA failed to express on the IRBC surface and was located within the parasite. Based on these findings, we propose that CLAG9 plays a critical role in the trafficking of PfEMP1s onto the IRBC surface. These results have important implications for the development of therapeutics for cerebral, placental, and other cytoadherence-associated malaria illnesses.


Assuntos
Antígenos de Protozoários/fisiologia , Moléculas de Adesão Celular/fisiologia , Plasmodium falciparum/fisiologia , Plasmodium falciparum/patogenicidade , Proteínas de Protozoários/fisiologia , Animais , Antígenos de Protozoários/química , Antígenos de Protozoários/genética , Sequência de Bases , Adesão Celular/fisiologia , Moléculas de Adesão Celular/biossíntese , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/genética , Sulfatos de Condroitina/fisiologia , DNA de Protozoário/genética , Membrana Eritrocítica/parasitologia , Membrana Eritrocítica/fisiologia , Membrana Eritrocítica/ultraestrutura , Eritrócitos/parasitologia , Feminino , Técnicas de Inativação de Genes , Genes de Protozoários , Interações Hospedeiro-Parasita/fisiologia , Humanos , Técnicas In Vitro , Microscopia Imunoeletrônica , Complexos Multiproteicos , Placenta/parasitologia , Placenta/fisiologia , Plasmodium falciparum/genética , Plasmodium falciparum/crescimento & desenvolvimento , Gravidez , Proteínas de Protozoários/biossíntese , Proteínas de Protozoários/química , Proteínas de Protozoários/genética
5.
J Neuroimmune Pharmacol ; 5(1): 83-91, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20020329

RESUMO

There are currently no consistent objective biochemical markers of alcohol abuse and alcoholism. Development of reliable diagnostic biomarkers that permit accurate assessment of alcohol intake and patterns of drinking is of prime importance to treatment and research fields. Diagnostic biomarker development in other diseases has demonstrated the utility of both open, systems biology, screening for biomarkers and more rational focused efforts on specific biomolecules or families of biomolecules. Long-term alcohol consumption leads to altered inflammatory cell and adaptive immune responses with associated pathologies and increased incidence of infections. This has led researchers to focus attention on identifying cytokine biomarkers in models of alcohol abuse. Alcohol is known to alter cytokine levels in plasma and a variety of tissues including lung, liver, and very importantly brain. A number of cytokine biomarker candidates have been identified, including: tumor necrosis factor-alpha, interleukin (IL)-1-alpha, IL-1-beta, IL-6, IL-8, IL-12, and monocyte chemoattractant protein-1. This is an emerging and potentially exciting avenue of research in that circulating cytokines may contribute to diagnostic biomarker panels, and a combination of multiple biomarkers may significantly increase the sensitivity and specificity of the biochemical tests aiding reliable and accurate detection of excessive alcohol intake.


Assuntos
Alcoolismo/sangue , Biomarcadores/sangue , Citocinas/sangue , Transtornos Induzidos por Álcool/metabolismo , Alcoolismo/diagnóstico , Alcoolismo/metabolismo , Animais , Citocinas/metabolismo , Etanol/efeitos adversos , Etanol/farmacologia , Humanos , Sistema Imunitário/efeitos dos fármacos , Sistema Imunitário/metabolismo , Modelos Imunológicos , Doenças do Sistema Nervoso/sangue , Doenças do Sistema Nervoso/líquido cefalorraquidiano
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