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1.
Can J Microbiol ; 61(7): 451-5, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25994226

ABSTRACT

Fast-growing mycobacteria such as Mycobacterium sp. and Mycobacterium smegmatis degrade natural sterols. They are a model to study tuberculosis. Interestingly, M. smegmatis has been found in river effluents derived from paper production, and therefore, it would be important to gain further insight into its capacity to synthesize steroids that are potential endocrine disruptors affecting the development and reproduction of fishes. To our knowledge, the capacity of M. smegmatis to synthesize estrogens and even testosterone has not been previously reported. Therefore, the objective of this study was to investigate the capacity of M. smegmatis to synthesize in vitro testosterone and estrogens from tritiated precursors and to investigate the metabolic pathways involved. Results obtained by thin-layer chromatography showed that (3)H-progesterone was transformed to 17OH-progesterone, androstenedione, testosterone, estrone, and estradiol after 6, 12, or 24 h of incubation. (3)H-androstenedione was transformed into testosterone and estrogens, mainly estrone, and (3)H-testosterone was transformed to estrone and androstenedione. Incubation with (3)H-dehydroepiandrosterone rendered androstenediol, testosterone, and estrogens. This ability to transform less potent sex steroids like androstenedione and estrone into other more active steroids like testosterone and estradiol or vice versa suggests that M. smegmatis can influence the amount of self-synthesized strong androgens and estrogens and can transform those found in the environment.


Subject(s)
Androgens/metabolism , Estrogens/metabolism , Mycobacterium smegmatis/metabolism , Steroids/metabolism , Androgens/analysis , Chromatography, Thin Layer , Dehydroepiandrosterone , Estrogens/analysis , Female , Humans , Mycobacterium smegmatis/chemistry , Steroids/analysis
2.
Inmunología (1987) ; 28(4): 161-172, oct.-dic. 2009. ilus
Article in English | IBECS | ID: ibc-108258

ABSTRACT

En este estudio se investiga la eficacia de M. tuberculosis muerto porcalor (Mtbi) y las Proteinas del Filtrado del Cultivo (PFC) en la activación de las células mononucleares (MC) y polimorfonucleares neutrolilos (PMN)de sangre periférica de pacientes tuberculosos. Se evalua en 16 pacientes tuberculosos, HIV- y 12 controles sanos el Estallido Respiratorio, los metabolitos derivados del NO y la producción de IL-2, IL-12 y TNFeÁ por las células estimuladas. Se detecta un incremento en la concentración de TNFeÁ en el sobrenadante de cultivo (s.c.) de PMN al comparar con los valoresbasales y en la evaluada en s.c. de MC y PMN estimulados, al ser comparadas con las del grupo control, excepto para los neutrófilos estimuladoscon PFC. Se mostraron niveles aumentados de IL-12 e IL-2 en s.c. de ambas células, MC y PMN estimuladas por en PTB, mientras que no se hallarondiferencias en los s.c. de los controles. Los valores basales de Estallido Respiratorio (RB) detectada en MC y PMN de pacientes no difirieron significantivamente de los correspondientes al grupo control. La expresión del Estallido Respiratorio en ambos tipos celulares fue menor en los pacientes que en los controles, independientemente del estímulo empleado. Sedeterminaron concentraciones de nitritos más elevadas en los sobrenadantesde las MC estimuladas con Mtbi y PFC provenientes de pacientes, comparadas con las de los controles. Los datos obtenidos relacionados al estímulo de la respuesta celular, nos proporcionan información sobre la inmunidad protectiva contra el M. tuberculosis y, a la vez, aportan algunos recursos útiles para una terapia anti-tuberculosa más eficiente (AU)


The efficacy of heat-killed Mycobacterium tuberculosis (HKMtb) andits culture filtrate proteins (CFP) to activate blood mononuclear cells (MC)and polymorphonuclear neutrophils (PMN) from tuberculosis patientswas investigated. Respiratory burst, NO-derived metabolites, IL-2, IL-12and TNF-¦Á production of stimulated cells from 16 HIV- tuberculosispatients and 12 healthy controls were analyzed. Increased amounts ofTNF-¦Á in supernatants from baseline and stimulated polymorphonuclear and mononuclear cells of tuberculosis patients were detected whencompared with controls, except for CFP stimulated neutrophils. Augmented IL-2 and IL-12 levels were observed in supernatants of both stimulated MC and PMN from TBP while no differences were found in control supernatants. The patients had a lower respiratory burst responsethan the controls, for both cell types, regardless of the stimulus employed. Higher nitrite concentrations were found in HKMtb- and CFP-stimulated mononuclear supernatants from patients, compared with controls. The obtained data of the stimulated cellular responses provides usinformation about the protective immunity against Mycobacterium tuberculosis and some resources to obtain a more efficient anti-tuberculous therapy (AU)1


Subject(s)
Humans , Tuberculosis/immunology , Mycobacterium tuberculosis/pathogenicity , Respiratory Burst/immunology , Bacterial Proteins/immunology , Nitrites/analysis , Cytokines/analysis , Tumor Necrosis Factor-alpha/analysis , Interleukin-2/analysis , Interleukin-12/analysis
3.
Medicina (B Aires) ; 66(2): 131-4, 2006.
Article in Spanish | MEDLINE | ID: mdl-16715761

ABSTRACT

Bacterial vaginosis (VB) is a syndrome characterized by overgrowth of endogenous Gram negative bacterial flora and the lack of the normal flora. Within bacterial enzymes, sialidases have been considered a virulence factor of many pathogenic microorganisms colonizing the different mucous membranes. Their presence in vaginal discharges can be correlated with VB. The aim of this study was to detect the activity of this enzyme in women with this syndrome and without clinical evidence of genital infection. Out of a total 112 women studied, 51 were patients with VB and the other 61 women presented normal vaginal flora. For the quantification of enzyme activity, the technique based on the enzymatic hydrolysis of a derivative acid of the acetyl metoxifenil muramic acid was used. In the studied population both groups shared values from 0.5 to 5.1 nmoles of metoxifenol, whereas only 11 out of 52 patients with VB (21.17%), registered more than 5.1 nmoles. The presence of sialidase activity is not enough to confirm VB, except for values greater than 5.5 nmoles of the metoxifenol produced in the enzymatic reaction.


Subject(s)
Neuraminidase/metabolism , Vagina/enzymology , Vaginosis, Bacterial/enzymology , Body Fluids/enzymology , Body Fluids/microbiology , Case-Control Studies , Female , Gardnerella vaginalis/isolation & purification , Humans , Statistics, Nonparametric , Syndrome , Vagina/microbiology , Vaginosis, Bacterial/diagnosis , Vaginosis, Bacterial/microbiology
4.
Medicina (B.Aires) ; 66(2): 131-134, 2006. graf
Article in Spanish | LILACS | ID: lil-440400

ABSTRACT

La vaginosis bacteriana (VB) es un síndrome caracterizado por el sobrecrecimiento bacteriano deflora endógena Gram negativa, que desplaza a la flora lactobacilar normal. Dentro de las enzimasbacterianas, las sialidasas han sido consideradas factores de virulencia de muchos microorganismos patógenosque colonizan las distintas mucosas. Su presencia en fluidos vaginales puede estar correlacionada con VB. Elpropósito de este estudio fue comprobar la actividad de dicha enzima en mujeres con este síndrome y sin evidenciaclínica de infección genital. Se estudiaron 112 mujeres (51 fueron pacientes con VB y 61 mujeres conflora colonizante habitual). Para la cuantificación de la actividad sialidasa se empleó la técnica basada en lahidrólisis enzimática de un derivado ácido del ácido metoxifenil acetil murámico. En la población estudiada seencontró que ambos grupos mostraron valores comprendidos entre 0.5 a 5.1 nmoles de metoxifenol, mientrasque 11 de 52 pacientes con VB (21.17%), registraron valores superiores a 5.1 nmoles. La presencia de actividadsialidasa solamente no es índice de VB, excepto para valores mayores de 5.5 nmoles de metoxifenol, producidosen la reacción enzimática.


Bacterial vaginosis (VB) is a syndromecharacterized by overgrowth of endogenous Gram negative bacterial flora and the lack of the normalflora. Within bacterial enzymes, sialidases have been considered a virulence factor of many pathogenic microorganismscolonizing the different mucous membranes. Their presence in vaginal discharges can be correlatedwith VB. The aim of this study was to detect the activity of this enzyme in women with this syndrome andwithout clinical evidence of genital infection. Out of a total 112 women studied, 51 were patients with VB andthe other 61 women presented normal vaginal flora. For the quantification of enzyme activity, the technique basedon the enzymatic hydrolysis of a derivative acid of the acetyl metoxifenil muramic acid was used. In the studiedpopulation both groups shared values from 0.5 to 5.1 nmoles of metoxifenol, whereas only 11 out of 52 patientswith VB (21.17%), registered more than 5.1 nmoles. The presence of sialidase activity is not enough to confirmVB, except for values greater than 5.5 nmoles of the metoxifenol produced in the enzymatic reaction.


Subject(s)
Humans , Female , Neuraminidase/metabolism , Vagina/enzymology , Vaginosis, Bacterial/enzymology , Body Fluids/enzymology , Body Fluids/microbiology , Case-Control Studies , Gardnerella vaginalis/isolation & purification , Statistics, Nonparametric , Syndrome , Vagina/microbiology , Vaginosis, Bacterial/diagnosis , Vaginosis, Bacterial/microbiology
5.
Medicina (B.Aires) ; 66(2): 131-134, 2006. graf
Article in Spanish | BINACIS | ID: bin-123449

ABSTRACT

La vaginosis bacteriana (VB) es un síndrome caracterizado por el sobrecrecimiento bacteriano deflora endógena Gram negativa, que desplaza a la flora lactobacilar normal. Dentro de las enzimasbacterianas, las sialidasas han sido consideradas factores de virulencia de muchos microorganismos patógenosque colonizan las distintas mucosas. Su presencia en fluidos vaginales puede estar correlacionada con VB. Elpropósito de este estudio fue comprobar la actividad de dicha enzima en mujeres con este síndrome y sin evidenciaclínica de infección genital. Se estudiaron 112 mujeres (51 fueron pacientes con VB y 61 mujeres conflora colonizante habitual). Para la cuantificación de la actividad sialidasa se empleó la técnica basada en lahidrólisis enzimática de un derivado ácido del ácido metoxifenil acetil murámico. En la población estudiada seencontró que ambos grupos mostraron valores comprendidos entre 0.5 a 5.1 nmoles de metoxifenol, mientrasque 11 de 52 pacientes con VB (21.17%), registraron valores superiores a 5.1 nmoles. La presencia de actividadsialidasa solamente no es índice de VB, excepto para valores mayores de 5.5 nmoles de metoxifenol, producidosen la reacción enzimática. (AU)


Bacterial vaginosis (VB) is a syndromecharacterized by overgrowth of endogenous Gram negative bacterial flora and the lack of the normalflora. Within bacterial enzymes, sialidases have been considered a virulence factor of many pathogenic microorganismscolonizing the different mucous membranes. Their presence in vaginal discharges can be correlatedwith VB. The aim of this study was to detect the activity of this enzyme in women with this syndrome andwithout clinical evidence of genital infection. Out of a total 112 women studied, 51 were patients with VB andthe other 61 women presented normal vaginal flora. For the quantification of enzyme activity, the technique basedon the enzymatic hydrolysis of a derivative acid of the acetyl metoxifenil muramic acid was used. In the studiedpopulation both groups shared values from 0.5 to 5.1 nmoles of metoxifenol, whereas only 11 out of 52 patientswith VB (21.17%), registered more than 5.1 nmoles. The presence of sialidase activity is not enough to confirmVB, except for values greater than 5.5 nmoles of the metoxifenol produced in the enzymatic reaction. (AU)


Subject(s)
Comparative Study , Humans , Female , Vaginosis, Bacterial/enzymology , Neuraminidase/metabolism , Vagina/enzymology , Vaginosis, Bacterial/microbiology , Statistics, Nonparametric , Syndrome , Body Fluids/enzymology , Body Fluids/microbiology , Vagina/microbiology , Gardnerella vaginalis/isolation & purification , Case-Control Studies , Vaginosis, Bacterial/diagnosis
6.
Medicina (B.Aires) ; 66(2): 131-134, 2006. graf
Article in Spanish | BINACIS | ID: bin-119582

ABSTRACT

La vaginosis bacteriana (VB) es un síndrome caracterizado por el sobrecrecimiento bacteriano deflora endógena Gram negativa, que desplaza a la flora lactobacilar normal. Dentro de las enzimasbacterianas, las sialidasas han sido consideradas factores de virulencia de muchos microorganismos patógenosque colonizan las distintas mucosas. Su presencia en fluidos vaginales puede estar correlacionada con VB. Elpropósito de este estudio fue comprobar la actividad de dicha enzima en mujeres con este síndrome y sin evidenciaclínica de infección genital. Se estudiaron 112 mujeres (51 fueron pacientes con VB y 61 mujeres conflora colonizante habitual). Para la cuantificación de la actividad sialidasa se empleó la técnica basada en lahidrólisis enzimática de un derivado ácido del ácido metoxifenil acetil murámico. En la población estudiada seencontró que ambos grupos mostraron valores comprendidos entre 0.5 a 5.1 nmoles de metoxifenol, mientrasque 11 de 52 pacientes con VB (21.17%), registraron valores superiores a 5.1 nmoles. La presencia de actividadsialidasa solamente no es índice de VB, excepto para valores mayores de 5.5 nmoles de metoxifenol, producidosen la reacción enzimática. (AU)


Bacterial vaginosis (VB) is a syndromecharacterized by overgrowth of endogenous Gram negative bacterial flora and the lack of the normalflora. Within bacterial enzymes, sialidases have been considered a virulence factor of many pathogenic microorganismscolonizing the different mucous membranes. Their presence in vaginal discharges can be correlatedwith VB. The aim of this study was to detect the activity of this enzyme in women with this syndrome andwithout clinical evidence of genital infection. Out of a total 112 women studied, 51 were patients with VB andthe other 61 women presented normal vaginal flora. For the quantification of enzyme activity, the technique basedon the enzymatic hydrolysis of a derivative acid of the acetyl metoxifenil muramic acid was used. In the studiedpopulation both groups shared values from 0.5 to 5.1 nmoles of metoxifenol, whereas only 11 out of 52 patientswith VB (21.17%), registered more than 5.1 nmoles. The presence of sialidase activity is not enough to confirmVB, except for values greater than 5.5 nmoles of the metoxifenol produced in the enzymatic reaction. (AU)


Subject(s)
Comparative Study , Humans , Female , Vaginosis, Bacterial/enzymology , Neuraminidase/metabolism , Vagina/enzymology , Vaginosis, Bacterial/microbiology , Statistics, Nonparametric , Syndrome , Body Fluids/enzymology , Body Fluids/microbiology , Vagina/microbiology , Gardnerella vaginalis/isolation & purification , Case-Control Studies , Vaginosis, Bacterial/diagnosis
7.
Immunol Lett ; 98(1): 45-8, 2005 Apr 15.
Article in English | MEDLINE | ID: mdl-15790507

ABSTRACT

Tuberculosis (TB) is the main cause of death by infection diseases worldwide. Considering that NO, TNF-alpha and TGF-beta participate a great deal in TB immunopathogenesis, we wished to analyse whether these mediators showed some relationship with the degree of pulmonary affectation. The sample comprised 29 TB (HIV-), inpatients with mild-moderate (n = 10) or advanced (n = 19) newly-diagnosed disease, together with 12 healthy controls HCo. Serum nitrite was assessed by reducing nitrate to nitrite, and further measured by the Griess reaction. Levels of TNF-alpha and TGF-beta were determined by ELISA (R&D Systems). Serum levels of TNF-alpha were significantly higher in the advanced TB cases if compared with HCo, (p < 0.05 ) and from values of Mild-Moderate TB patients (p < 0.05). Serum levels of TGF-beta from advanced TB patients have increased values if compared with Hco (p < 0.005) and Mild-Moderate patients (p < 0.05). These values were also significantly different from Mild-Moderate cases + HCo (p = 0.01) Advanced TB patients had significantly reduced nitrite levels compared with those of Mild-Moderate patients and HCo (p < 0.002). Taken as a whole NO-derived metabolites in TB patients (M-M and Advanced cases) remained lower than values in HCo (p = 0.005) A negative correlation was found when comparing the two cytokines with nitrites(r = -0.44 ).TGF-beta and TNF-alpha were positively correlated (r = 0.44, p < 0.01), 0.44, p < 0.01. In synthesis, the inverse correlation found between both cytokines concentrations and NO levels in TB patients may be viewed as a consequence of a more predominant TGF-beta effect.


Subject(s)
Nitric Oxide/blood , Transforming Growth Factor beta/blood , Tuberculosis, Pulmonary/blood , Tumor Necrosis Factor-alpha/metabolism , Adult , Humans , Mycobacterium tuberculosis/metabolism , Severity of Illness Index , Tuberculosis, Pulmonary/physiopathology
12.
Rev. microbiol ; 23(2): 66-70, abr.-jun. 1992. tab, graf
Article in Portuguese | LILACS | ID: lil-279919

ABSTRACT

Comprovado experimentalmente o efeito anti-tumoral do Staphylococcus aureus sobre um sarcoma transplantado em ratos(S-E 100).Ratos adultos endocriados e inoculados s.c.com S-E 100 receberam via s.c. uma suspensäo de 8*10elevado a sexta S.aureus mortos por tindalizaçäo.Grupos experimentais:1)S-E 100+S.aureus 7 dias antes:2)S-E 100+S.aureus simultaneamente;3)S-E 100+S.aureus 7 dias depois;4)S-E 100 (grupo de controle).A incidência do S-E 100 näo modificou de forma significativa nos grupos experimentais.As medidas efetuadas nos dias 7, 14, 21, 28 depois de inoculado o tumor evidenciaram que os animais desafiados, prévia e simultaneamente com S.aureus apresentavam tumores com um tamanho significativamente menor que o grupo de controle.Nos animais que pertenciam aos grupos 1 e 2, o período de sobrevivência foi significativamente superior ao grupo controle, mas a porcentagem de mortalidade näo foi diferente entre os grupos.O estudo histológico do tumor evidenciou uma maior superfície de tecido necrosado, sete(7) dias antes do desafio tumoral com o microorganismo, e nos ratos inoculados simultaneamente, em relaçäo aos animais que pertenciam ao grupo de controle.Conclusäo:S.aureus quando é inoculado antes(vacina)ou em forma simultânea ao desafio com sarcoma E-100 exerce uma inibiçäo do crescimento do tumor e também induz um aumento no processo de necrose do tumor além de aumentar o período de sobrevida dos animais.


Subject(s)
Animals , Rats , Rats , Sarcoma/epidemiology , Staphylococcus aureus/classification , Staphylococcus aureus/growth & development , Tumor Necrosis Factor-alpha/ultrastructure
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