RESUMO
Systemic sclerosis (SSc) is an autoimmune disease that affects skin and multiple internal organs. TGF-ß, a central trigger of cutaneous fibrosis, activates fibroblasts with the involvement of the stress-inducible chaperone heat shock protein 90 isoform α (Hsp90α). Available evidence supports overexpression and secretion of Hsp90α as a feature in profibrotic pathological conditions. The aim of this work is to investigate the expression and function of Hsp90α in experimental models of skin fibrosis such as human fibroblasts, C57BL/6 mice, and in human SSc. For this purpose, we generated a new experimental model based on doxorubicin administration with improved characteristics with respect to the bleomycin model. We visualized disease progression in vivo by fluorescence imaging. In this work, we obtained Hsp90α mRNA overexpression in human skin fibroblasts, in bleomycin- and doxorubicin-induced mouse fibrotic skin, and in lungs of bleomycin- and doxorubicin-treated mice. Hsp90α-deficient mice showed significantly decreased skin thickness compared with wild-type mice in both animal models. In SSc patients, serum Hsp90α levels were increased in patients with lung involvement and in patients with the diffuse form of SSc (dSSc) compared with patients with the limited form of SSc. The serum Hsp90α levels of patients dSSc were correlated with the Rodnan score and the forced vital capacity variable. These results provide new supportive evidence of the contribution of the Hsp90α isoform in the development of skin fibrosis. In SSc, these results indicated that higher serum levels were associated with dSSc and lung fibrosis.
Assuntos
Proteínas de Choque Térmico HSP90/metabolismo , Escleroderma Sistêmico , Dermatopatias , Animais , Bleomicina , Modelos Animais de Doenças , Doxorrubicina/metabolismo , Fibroblastos , Fibrose , Proteínas de Choque Térmico/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Escleroderma Sistêmico/metabolismo , Pele , Dermatopatias/patologiaRESUMO
Sepsis is the leading cause of acute kidney injury in critically ill patients. Tumor necrosis factor-α (TNF-α) has been implicated in the pathogenesis of septic kidney injury; however, the sites and mechanisms of renal TNF-α production during sepsis remain to be defined. In the present study, we showed that TNF-α expression is increased in medullary thick ascending limbs (MTALs) of mice with sepsis induced by cecal ligation and puncture. Treatment with lipopolysaccharide (LPS) for 3 h in vitro also increased MTAL TNF-α production. Sepsis and LPS increased MTAL TNF-α expression through activation of the myeloid differentiation factor 88 (MyD88)-IL-1 receptor-associated kinase 1-ERK signaling pathway. Pretreatment with monophosphoryl lipid A (MPLA), a nontoxic immunomodulator that protects against bacterial infection, eliminated the sepsis- and LPS-induced increases in MTAL TNF-α production. The suppressive effect of MPLA on TNF-α was mediated through activation of a phosphatidylinositol 3-kinase-dependent pathway that inhibits MyD88-dependent ERK activation. This likely involves MPLA-phosphatidylinositol 3-kinase-mediated induction of Tollip, which negatively regulates the MyD88-ERK pathway by inhibiting activation of IL-1 receptor-associated kinase 1. These regulatory mechanisms are similar to those previously shown to mediate the effect of MPLA to prevent sepsis-induced inhibition of MTAL [Formula: see text] absorption. These results identify the MTAL as a site of local TNF-α production in the kidney during sepsis and identify molecular mechanisms that can be targeted to attenuate renal TNF-α expression. The ability of MPLA pretreatment to suppress MyD88-dependent ERK signaling in the MTAL during sepsis has the dual beneficial effects of protecting tubule transport functions and attenuating harmful proinflammatory responses.
Assuntos
Citocinas/metabolismo , Medula Renal/efeitos dos fármacos , Lipídeo A/análogos & derivados , Alça do Néfron/efeitos dos fármacos , Sepse/metabolismo , Animais , Medula Renal/metabolismo , Lipídeo A/farmacologia , Lipopolissacarídeos/farmacologia , Alça do Néfron/metabolismo , Masculino , Camundongos , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
BACKGROUND: At present only monoclonal EIA (enzyme-immunoassay) stool antigen-tests have obtained optimal accuracy in the diagnosis of Helicobacter pylori. Our aim was to evaluate the accuracy of two stool antigen-tests, the validated Premier Platinum HpSA PLUS (EIA test) and the newly available ImmunoCard STAT! HpSA HD (rapid test) for the initial diagnosis and the confirmation of eradication of H. pylori infection. PATIENTS AND METHODS: Patients with indication of H. pylori diagnosis, or confirmation after treatment were included. Data were coded to protect personal data and ensure blindness between tests. Accuracy was considered as coincident diagnosis with the gold standard (13C-urea breath test, UBT). The EIA was used as a bench standard. All stool tests were performed in duplicate. RESULTS: 264 patients completed the protocol (100 naïve, 164 post-eradication). Average age was 52 years, 61% women, 11% ulcer. Positive diagnoses by UBT were 41% for naïve and 17% for post-eradication. Overall ImmunoCard and EIA accuracies were respectively 91% (95%C.I.=88-94%) and 89% (86-93%), sensitivities 72% (67-78%) and 72% (67-78%), and specificities 98% (96-100%), and 95% (92-97%). Concordance between ImmunoCard and EIA was 95% (93-98%). DISCUSSION: Our results indicate that the newly available ImmunoCard rapid stool antigen-test achieves 90% accuracy, with high specificity but suboptimal sensitivity. The ImmunoCard attained equivalent accuracies as the EIA bench standard, with 95% concordance.
Assuntos
Antígenos de Bactérias/análise , Fezes/microbiologia , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/imunologia , Imunoensaio/métodos , Técnicas Imunoenzimáticas/métodos , Kit de Reagentes para Diagnóstico , Idoso , Área Sob a Curva , Testes Respiratórios , Dispepsia/microbiologia , Fezes/química , Feminino , Helicobacter pylori/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Úlcera Péptica/microbiologia , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
LPS inhibits HCO3- absorption in the medullary thick ascending limb (MTAL) through a Toll-like receptor 4 (TLR4)-myeloid differentiation factor 88 (MyD88)-extracellular signal-regulated kinase (ERK) pathway that is upregulated by sepsis. Pretreatment with the nontoxic immunomodulator monophosphoryl lipid A (MPLA) prevents inhibition by LPS through activation of a TLR4-TIR-domain-containing adaptor-inducing interferon-ß (TRIF)-phosphatidylinositol 3-kinase (PI3K) pathway that prevents LPS-induced ERK activation. Here, we identified the molecular mechanisms that underlie the protective inhibitory interaction between the MPLA-PI3K and LPS-ERK pathways. Treatment of mouse MTALs with LPS in vitro increased phosphorylation of IL-1 receptor-associated kinase (IRAK)-1, a critical mediator of LPS signaling downstream of TLR4-MyD88. Activation of ERK by LPS was eliminated by a selective IRAK-1 inhibitor, establishing IRAK-1 as the upstream mediator of ERK activation. Pretreatment of MTALs with MPLA in vitro prevented LPS-induced IRAK-1 activation; this effect was dependent on PI3K. Treatment of MTALs with MPLA increased expression of Toll-interacting protein (Tollip), an inducible protein that negatively regulates LPS signaling by inhibiting IRAK-1. The MPLA-induced increase in Tollip protein level was prevented by PI3K inhibitors. In coimmunoprecipitation experiments, MPLA increased the amount of Tollip stably bound to IRAK-1, an interaction that inhibits IRAK-1 activation. These results support a mechanism whereby MPLA increases Tollip expression in the MTAL through a PI3K-dependent pathway. Tollip, in turn, inhibits LPS-induced TLR4 signaling by suppressing activation of IRAK-1, thereby preventing activation of ERK that inhibits HCO3- absorption. These studies show that MPLA induces reprogramming of MTAL cells that protects against LPS stimulation and identify IRAK-1 and Tollip as new therapeutic targets to prevent renal tubule dysfunction in response to infectious and inflammatory stimuli.
Assuntos
Adjuvantes Imunológicos/farmacologia , Bicarbonatos/metabolismo , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lipídeo A/análogos & derivados , Alça do Néfron/efeitos dos fármacos , Reabsorção Renal/efeitos dos fármacos , Sepse/tratamento farmacológico , Proteínas Adaptadoras de Transporte Vesicular/genética , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Citoproteção , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Lipídeo A/farmacologia , Alça do Néfron/metabolismo , Alça do Néfron/fisiopatologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Fosforilação , Ratos Sprague-Dawley , Sepse/metabolismo , Sepse/fisiopatologia , Transdução de Sinais , Receptor 4 Toll-Like/metabolismoRESUMO
BACKGROUND: Helicobacter pylori infection is associated with chronic gastritis, ulcers and gastric cancer. Antimicrobial resistance has increased worldwide affecting the efficacy of current treatments. Most guidelines recommend implementation of regional surveillance of primary antibiotic resistance of H pylori. Only a fraction of individuals infected with H pylori develop gastric diseases which are related to virulence factors of the bacteria. The aims of the study were to determine the primary antimicrobial resistance rates of H pylori and to know the virulence factors prevalence of strains circulating in Southern Europe. MATERIALS AND METHODS: Susceptibility testing by Etest to clarithromycin, levofloxacin, metronidazole, amoxicillin and tetracycline was performed in 102 isolates (99 naïve patients). The prevalence of virulence factors (cagA, vacA, oipA, babA and dupA) was evaluated in 102 H pylori isolates from patients with mild-disease symptoms and in 22 isolates from patients with severe-disease symptoms. RESULTS: Primary resistance rates were 12.1% to clarithromycin, 13.1% to levofloxacin, 24.2% to metronidazole and 0% to amoxicillin and tetracycline. Combined resistance to clarithromycin and levofloxacin was 3% and to clarithromycin and metronidazole 4%. Prevalence of virulence factors in the mild- and severe-disease group was 35.3% and 81.8% for cagA, 20.6% and 54.5% for cagA/vacAs1m1, 94.1% and 95.4% for babA2, 78.4% and 100% for oipA and 30.4% and 18.2% for dupA. CONCLUSIONS: Primary antimicrobial resistance rates were under 15% for clarithromycin and levofloxacin. The prevalence of H pylori carrying the virulent genotype cagA/vacAs1m1 was higher than 20% in the mild-disease and 54% in the severe-disease symptom group.
Assuntos
Farmacorresistência Bacteriana/genética , Infecções por Helicobacter/microbiologia , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/patogenicidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Feminino , Genótipo , Helicobacter pylori/genética , Humanos , Masculino , Pessoa de Meia-Idade , Filogeografia , Espanha , Fatores de Virulência/genética , Adulto JovemRESUMO
BACKGROUND: Inositols (INOs) supplementation during pregnancy, specifically the combination of myo-inositol (MI) and D-chiro-inositol (DCI), has been reported to improve vascular parameters in women with gestational diabetes mellitus. We demonstrated previously that offspring born to pregnant mice lacking the endothelial nitric oxide synthase (eNOS+/-) gene have hypertension (HTN) as adults and, when fed a high-fat diet (HFD), develop a metabolic syndrome (MS) phenotype. OBJECTIVE: Our aim was to evaluate whether INOs treatment in pregnancy complicated by MS improves the vascular and metabolic profile in mice offspring programmed in utero to develop HTN and MS. MATERIALS AND METHODS: Heterozygous eNOS+/- mice fed an HFD manifest a MS phenotype. Female eNOS+/- mice with MS were bred with a wild-type (WT) male. On gestational day 1, pregnant females were randomly allocated to receive either a mixture of INOs (MI/DCI: 7.2/0.18 mg/mL) or water as placebo until delivery. The female offspring obtained were genotyped and categorized as: WT (genetically normal, with eNOS gene) and eNOS+/- offspring (genetically modified, heterozygous for eNOS gene). Both offspring developed in an abnormal uterine environment due to maternal MS. At 9-10 weeks of age, the offspring underwent a glucose tolerance test (GTT) and systolic blood pressure (SBP) measurement. The mice were then sacrificed, and the carotid arteries were isolated for evaluation of vascular responses. Responses to phenylephrine (PE), in the presence and absence of a nonspecific nitric oxide inhibitor (N-nitro-L-arginine methyl ester [L-NAME]), the vasodilator acetylcholine (ACh), and sodium nitroprusside (SNP) were assessed. RESULTS: The GTT showed lower glucose levels in both eNOS+/-INOs (P = .03) and WT-INOs (P = .05) offspring born to MS dams on INOs supplementation compared to offspring born to untreated dams. SBP was higher in eNOS+/- offspring compared to WT (169 ± 7 vs 142 ± 9 mm Hg, respectively, P = .04) and INOs treatment decreased SBP in WT-INOs (110 ± 10 mm Hg, P = .01) but not in eNOS+/-INOs offspring. Maximal (%Max) contractile response to PE was higher in eNOS+/- offspring born to MS dams and was decreased in those born to MS dams treated with INOs (%Max, eNOS+/-, 123 ± 7 vs eNOS+/-INOs, 82 ± 11 mm Hg, P = .007). No differences were seen in PE contractile responses in WT offspring born to MS dams treated or not treated with INOs (WT, 92 ± 4 vs WT-INOs, 75 ± 7). The L-NAME response was decreased in eNOS+/-INOs and WT-INOs offspring compared to untreated ones. The ACh vasorelaxation was impaired in eNOS+/- and WT offspring born to MS dams, and maternal INOs treatment improved offspring vascular relaxation in both offspring (P = .01 and P = .03, respectively). No differences were seen in response to SNP. CONCLUSION: Inositols supplementation improved glucose tolerance, SBP, and vascular responses in adult eNOS+/- and WT offspring born to dams with MS. Interestingly, WT born to MS dams show an altered vascular profile similar to eNOS+/- offspring and exhibit an improved response to INOs treatment. Our findings suggest that the benefits of INOs treatment are more pronounced in offspring exposed to environmental factors in utero, and less likely in those due to genetic factors.
Assuntos
Hipertensão/prevenção & controle , Inositol/uso terapêutico , Síndrome Metabólica/prevenção & controle , Complicações na Gravidez/tratamento farmacológico , Cuidado Pré-Natal/métodos , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Complexo Vitamínico B/uso terapêutico , Animais , Biomarcadores/sangue , Esquema de Medicação , Feminino , Hipertensão/sangue , Hipertensão/etiologia , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/tratamento farmacológico , Síndrome Metabólica/etiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Gravidez , Efeitos Tardios da Exposição Pré-Natal/sangue , Efeitos Tardios da Exposição Pré-Natal/etiologia , Distribuição AleatóriaRESUMO
The TGFß superfamily is composed of more than 33 growth and differentiation factors, including TGFß1, ß2, ß3, BMPs, GDFs, nodal-related proteins, and activins. These members usually exert pleiotropic actions on several tissues and control multiple cellular processes, such as cell growth, cell survival, cell migration, cell fate specification, and differentiation, both during embryonic development and postnatal life. Although the effects of these factors on immune responses were elucidated long ago, most studies have been focused on the actions of TGFßs on T cells, as major regulators of adaptive immunity. In this review, we discuss new findings about the involvement of TGFß superfamily members in the control of B cell development and function. Moreover, the potential contribution of TGFß signaling to control B cell-mediated autoimmune diseases and its utility in the design of new therapies are also discussed.
Assuntos
Autoimunidade/fisiologia , Linfócitos B/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Autoimunidade/genética , Diferenciação Celular/fisiologia , Sobrevivência Celular/fisiologia , Humanos , Transdução de Sinais/fisiologiaRESUMO
KEY POINTS: Nitric oxide is essential in the vascular adaptation to pregnancy, as knockout mice lacking nitric oxide synthase (NOS3) have abnormal utero-placental perfusion, hypertension and growth restriction. We previously showed with ex vivo studies on transgenic animals lacking NOS3 that adverse intrauterine environment alters fetal programming of vascular reactivity in adult offspring. The current research shows that altered vascular reactivity correlates with higher blood pressure in vivo. Our data suggest that higher blood pressure depends on both genetic background (NOS3 deficiency) and uterine environment, becomes more evident with age (> 7 postnatal weeks), activity and stress, is gender specific (preponderant among males), and can be affected by the sleep-awake cycle. In utero or early postnatal life (< 7 weeks), before onset of hypertension, may represent a potential window for intervention to prevent future cardiovascular disorders. ABSTRACT: Nitric oxide is involved in the vascular adaptation to pregnancy. Using transgenic animals, we previously showed that adverse intrauterine environment alters vascular reactivity in adult offspring. The aim of our study was to determine if altered vascular programming is associated with abnormal blood pressure (BP) profiles in vivo. Mice lacking a functional endothelial nitric oxide synthase (KO, NOS3-/- ) and wild-type mice (WT, NOS3+/+ ) were crossbred to generate homozygous NOS3-/- (KO), maternally derived heterozygous NOS3+/- (KOM: mother with adverse intrauterine environment from NOS3 deficiency), paternally derived heterozygous NOS3+/- (KOP: mother with normal in utero milieu) and NOS3+/+ (WT) litters. BP was measured in vivo at 7, 14 and 21 weeks of age. After univariate analysis, multivariate population-averaged linear regression models were used to identify factors affecting BP. When compared to WT offspring, systolic (SBP), diastolic (DBP) and mean (MAP) BP progressively increased from KOP, to KOM, and peaked among KO (P < 0.001), although significance was not reached for KOP. Higher BP was also associated with male gender, older age (> 7 postnatal weeks), higher locomotor activity, daytime recordings, and recent blood pressure transducer insertion (P < 0.001). Post hoc analysis showed that KOM had higher SBP than KOP (P < 0.05). Our study indicates that adverse intrauterine environment contributes, along with multiple other factors, to account for hypertension; moreover, in utero or early postnatal life may represent a possible therapeutic window for prevention of cardiovascular disease later in life.
Assuntos
Pressão Sanguínea , Desenvolvimento Fetal/fisiologia , Óxido Nítrico Sintase Tipo III/genética , Animais , Feminino , Frequência Cardíaca , Locomoção , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Óxido Nítrico Sintase Tipo III/fisiologia , Telemetria , ÚteroRESUMO
BACKGROUND: Treatment of nonsevere hypertension during pregnancy is controversial. Sildenafil is a phosphodiesterase inhibitor that potentiates nitric oxide by promoting vasodilation. Nitric oxide plays a vital role in mediating the vascular adaptations during pregnancy. OBJECTIVE: The objective of the study was to determine whether treatment with sildenafil during pregnancy would lower maternal systolic blood pressure without adversely affecting fetal growth. STUDY DESIGN: Females with nonsevere hypertension (endothelial nitric oxide synthase(+/-)) were cross-bred with normotensive wild-type males. At gestational day 1, pregnant dams were randomized to either sildenafil (0.4 mg/mL per day, comparable dose used in human pregnancy) or water for 3 weeks. Four groups were then generated: wild type (n = 7), wild type-sildenafil (n = 11), endothelial nitric oxide synthase(+/-) (n = 8), and endothelial nitric oxide synthase(+/-)sildenafil (n = 7). On gestational day 18, systolic blood pressure was measured. Dams were killed, fetal and placental weights were obtained, and carotid arteries were dissected to measure in vitro vascular reactivity with a wire-myography system. Responses to phenylephrine, L-NG-nitroarginine methyl ester, acetylcholine, and sodium nitroprusside were studied. RESULTS: Mean systolic blood pressure was elevated in the endothelial nitric oxide synthase(+/-) dams compared with wild-type controls (P = .03). Treatment with sildenafil decreased systolic blood pressure in the endothelial nitric oxide synthase(+/-)-treated dams compared with nontreated endothelial nitric oxide synthase(+/-) dams (P = .03). No differences were seen in the wild-type dams with or without sildenafil (P = .47). Fetuses from endothelial nitric oxide synthase(+/-) dams were smaller compared with wild-type controls (P < .001); however, when these endothelial nitric oxide synthase(+/-) dams were treated with sildenafil, fetal weight increased compared with the nontreated endothelial nitric oxide synthase(+/-) group (P < .001). No difference were seen in wild-type groups treated or not treated with sildenafil (P = .41). Placental weights were not significantly different among groups (endothelial nitric oxide synthase(+/-)sildenafil vs endothelial nitric oxide synthase(+/-) [P = .48]; wild-type-sildenafil vs wild type [P = .52]). Maximal vascular contraction induced by phenylephrine was blunted in endothelial nitric oxide synthase(+/-) dams treated with sildenafil compared with nontreated endothelial nitric oxide synthase(+/-) dams (P < .01). No change in contractile response was seen in wild-type groups treated or not treated (P = .53). When vessels were preincubated with L-NG-nitroarginine methyl ester, the contractile responses were similar among all groups (P = .54). In addition, maximal vascular relaxation induced by acetylcholine was improved in the endothelial nitric oxide synthase(+/-) dams treated with sildenafil compared with endothelial nitric oxide synthase(+/-) nontreated dams (P < .01). No change in relaxation response was seen in wild-type groups treated or not treated (P = .62). Sodium nitroprusside did not change the contractile response in any of the groups (P = .31). CONCLUSION: Pregnant dams deficient in endothelial nitric oxide synthase, a nonsevere hypertensive murine model, treated with sildenafil had lower maternal systolic blood pressure, increased fetal growth, and improvement in vascular reactivity. Treatment with sildenafil may be beneficial in pregnancies complicated by nonsevere hypertension.
Assuntos
Desenvolvimento Fetal , Hipertensão Induzida pela Gravidez/tratamento farmacológico , Inibidores da Fosfodiesterase 5/farmacologia , Citrato de Sildenafila/farmacologia , Animais , Artérias Carótidas/efeitos dos fármacos , Feminino , Peso Fetal , Modelos Animais , Placenta/fisiologia , GravidezRESUMO
BACKGROUND: Nonbismuth quadruple (concomitant) regimen is recommended for first-line empirical Helicobacter pylori (HP) eradication treatment when clarithromycin resistance is more than 15-20%. Our objective was to evaluate the efficacy and tolerability of concomitant versus antimicrobial susceptibility-guided treatment in an area with high rates of clarithromycin resistance. METHODS: Three hundred consecutive HP-infected patients received antimicrobial susceptibility-guided therapy or empirical concomitant therapy for 10 days. The concomitant regimen was omeprazole (20 mg/12 hour), amoxicillin (1 g/12 hour), clarithromycin (500 mg/12 hour), and metronidazole (500 mg/12 hour) (OACM). Patients diagnosed by culture received one of three combinations of antibiotics based on susceptibility results: omeprazole, amoxicillin, and clarithromycin (OAC); omeprazole, amoxicillin, and levofloxacin (OAL); or omeprazole, amoxicillin, and metronidazole (OAM), at the aforementioned doses (and 500 mg/12 hour in the case of levofloxacin). Eradication was confirmed with a (13)C urea breath test, 6 weeks after treatment. Adverse events and adherence were assessed with questionnaires and reviewing medication sachets. RESULTS: The mean age was 50 years, 59% were women, and 14% had peptic ulcers. Concomitant and antimicrobial susceptibility-guided eradication rates were, respectively, 87% and 94% by intention-to-treat (p = .08) and 89% and 95% (p = .08) per protocol per-protocol analysis. Adverse effects were reported in 31% of patients on OACM and 15% of those on susceptibility-guided therapy (p < .05). CONCLUSIONS: For HP eradication in a region with high rates of multiple drug resistance, antimicrobial susceptibility-guided therapy is more effective than empirical concomitant therapy.
Assuntos
Antibacterianos/administração & dosagem , Claritromicina/administração & dosagem , Farmacorresistência Bacteriana , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Adulto , Idoso , Quimioterapia Combinada , Feminino , Infecções por Helicobacter/microbiologia , Helicobacter pylori/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
OBJECTIVES: To survey antibiotic resistance among Streptococcus pyogenes isolates collected from 2005 to 2012, to characterize those showing erythromycin resistance and to analyse the association of certain emm types with erythromycin resistance or susceptibility. METHODS: Resistance determinants or mutations conferring erythromycin, clindamycin, tetracycline and fluoroquinolone resistance were analysed. All erythromycin-resistant isolates and a sample of erythromycin-susceptible isolates were emm typed. Multilocus sequence typing was performed for representative emm types. RESULTS: Antimicrobial susceptibility was studied for 12â346 S. pyogenes isolates. Erythromycin, clindamycin and tetracycline resistance showed a decreasing trend. In 2012, 2.8% of isolates were erythromycin resistant versus 7.5% in 2005 and 11.7% in 2006. Although 21 clones were involved, 4 clones accounted for almost 90% of erythromycin-resistant isolates. The emm12/ST36 clone, carrying the mef(A) gene, was the predominant (41.1%) erythromycin-resistant clone, with an incidence peak in 2008, followed by a gradual decline. The M phenotype predominated each year except for 2005, when two of the main erythromycin-resistant clones (emm11/ST403 and emm28/ST52) harboured an erm(B) gene. Erythromycin resistance was significantly higher in adults than in children. Skin isolates showed the highest erythromycin resistance rate; among these, perianal isolates frequently belonged to the emm28/ST52 clone. The emm type was not a predictor of erythromycin resistance; however, most emm11 and emm12 were erythromycin-resistant isolates. Macrolide consumption was similar throughout the study period. Only two isolates with a high level of levofloxacin resistance were detected. CONCLUSIONS: Resistance was mainly related to the circulation of emm12/ST36, emm11/ST403, emm28/ST52 and emm4/ST39 clones, all of which declined throughout the study period.
Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Eritromicina/farmacologia , Infecções Estreptocócicas/microbiologia , Streptococcus pyogenes/efeitos dos fármacos , Adolescente , Adulto , Idoso , Antígenos de Bactérias/genética , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Transporte/genética , Criança , Pré-Escolar , Farmacorresistência Bacteriana/genética , Europa (Continente) , Genótipo , História do Século XXI , Humanos , Lactente , Recém-Nascido , Macrolídeos/farmacologia , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutação , Fenótipo , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/história , Streptococcus pyogenes/genética , Streptococcus pyogenes/isolamento & purificação , Adulto JovemRESUMO
OBJECTIVE: Fetal alcohol syndrome (FAS) is the most common cause of nongenetic mental retardation. Oxidative stress is one of the purported mechanisms. Nicotinamide adenine dinucleotide phosphate oxidase (NOX) is an enzyme involved in the production of reactive oxygen species. Our objective was to evaluate NOX in the fetal brain of a well-validated mouse model of FAS. STUDY DESIGN: Timed, pregnant C57BL/6J mice were injected intraperitoneally with 0.03 mL/g of either 25% ethyl alcohol or saline. Fetal brain, liver, and placenta were harvested on gestational day 18. The unit of analysis was the litter; tissue from 6-8 litters in the alcohol and control group was isolated. Evaluation of messenger ribonucleic acid (mRNA) expression of NOX subunits (DUOX1, DUOX2, NOX1, NOX2, NOX3, NOX4, NOXA1, NOXO1, RAC1, p22phox, and p67phox) was performed using quantitative real-time polymerase chain reaction; alcohol vs placebo groups were compared using a Student t test or a Mann-Whitney test (P < .05). RESULTS: Alcohol exposed fetal brains showed significant up-regulation in subunits DUOX2 (1.61 ± 0.28 vs 0.84 ± 0.09; P = .03), NOXA1 (1.75 ± 0.27 vs 1.09 ± 0.06; P = .04), and NOXO1 (1.59 ± 0.10 vs 1.28 ± 0.05; P = .02). Differences in mRNA expression in the placenta were not significant; p67phox was significantly up-regulated in alcohol-exposed livers. CONCLUSION: Various NOX subunits are up-regulated in fetal brains exposed to alcohol. This effect was not observed in the fetal liver or placenta. Given the available evidence, the NOX system may be involved in the causation of FAS through the generation of reactive oxygen species and may be a potential target for preventative treatment in FAS.
Assuntos
Transtornos do Espectro Alcoólico Fetal/enzimologia , NADPH Oxidases/fisiologia , Animais , Encéfalo/embriologia , Encéfalo/enzimologia , Modelos Animais de Doenças , Feminino , Transtornos do Espectro Alcoólico Fetal/fisiopatologia , Feto/enzimologia , Camundongos Endogâmicos C57BL , NADP , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima/fisiologiaRESUMO
OBJECTIVE: Preeclampsia alters fetal programming and results in long-term metabolic consequences in the offspring. Pravastatin has been shown to prevent preeclampsia in animal models. Our aim was to characterize the effects of preeclampsia on fetal programming of adult growth and metabolic function, and evaluate the role of preventive pravastatin therapy, using a well characterized murine model. STUDY DESIGN: CD-1 mice were injected through the tail vein with adenovirus carrying soluble fms-like tyrosine kinase 1 (sFlt-1) and randomly allocated to pravastatin (5 mg/kg/day; sFlt-1/prav, n = 7) or water (sFlt-1, n = 6) until weaning. A control group was injected with adenovirus carrying the murine immunoglobulin G2α Fc fragment (mFc, n = 8). Male and female offspring (6-8/group) were weighed every month until 6 months of age. Intraperitoneal glucose tolerance testing was performed after 16 hours of fasting at 3 and 6 months of age; glucose and insulin responses were measured. RESULTS: sFlt-1 offspring weight was lower than mFc control (P < .001) until 2 months of age for females and 5 months of age for males (P < .001). There were no differences in postnatal growth between mFc and sFlt-1/prav offspring. At 3 and 6 months, female sFlt-1 offspring had higher glucose response compared with mFc and sFlt-1/prav. Three-month-old male sFlt-1 had lower insulin response compared with mFc offspring. CONCLUSION: Preeclampsia alters postnatal growth and metabolic function in the adult offspring in this animal model. Maternal therapy with prav prevents some of these alterations in the offspring.
Assuntos
Glicemia/metabolismo , Desenvolvimento Fetal/efeitos dos fármacos , Insulina/sangue , Camundongos/crescimento & desenvolvimento , Pravastatina/uso terapêutico , Pré-Eclâmpsia/tratamento farmacológico , Análise de Variância , Animais , Área Sob a Curva , Peso Corporal , Proteínas de Ciclo Celular , Modelos Animais de Doenças , Feminino , Masculino , Camundongos/metabolismo , Pravastatina/farmacologia , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/induzido quimicamente , Gravidez , Receptores Acoplados a Proteínas G , Receptor 1 de Fatores de Crescimento do Endotélio VascularRESUMO
OBJECTIVE: Despite the importance of Treg cells in the maintenance of immunologic tolerance, the mechanisms that control their generation and activity are unknown. Since the cell cycle inhibitor p27(Kip1) (p27) was involved in T cell anergy, we undertook this study to explore its role in both Treg cell processes. METHODS: The development of type II collagen-induced arthritis (CIA) and lupus-like abnormalities was compared between transgenic mice overexpressing human Bcl-2 in T cells (BCL2-TgT mice) and nontransgenic mice that were deficient or not deficient in p27. The contribution of Treg cells to disease evolution was also explored. Finally, the in vitro activity of Treg cells and their differentiation from naive CD4+ cells was compared between these strains of mice. RESULTS: BCL2-TgT mice were protected against CIA by a Treg cell-dependent mechanism. In association with this protection, the overexpression of Bcl-2 in T cells enhanced the differentiation and activity of Treg cells. Both Bcl-2 effects were independent of its antiapoptotic activity but dependent on its capacity to induce the expression of p27 that augmented the strength of transforming growth factor ß (TGFß) signaling in T cells. Accordingly, down-modulation of p27 expression in BCL2-TgT mice promoted CIA. In addition, p27 deficiency in aged C57BL/6 mice reduced the number and activity of Treg cells and induced the development of mild lupus-like abnormalities. CONCLUSION: Our results point to p27 as a critical regulator of Treg cell differentiation and function through the positive modulation of TGFß signaling strength in T cells.
Assuntos
Artrite Experimental/imunologia , Autoimunidade/imunologia , Diferenciação Celular/imunologia , Inibidor de Quinase Dependente de Ciclina p27/genética , Linfócitos T Reguladores/imunologia , Animais , Artrite Experimental/genética , Artrite Experimental/metabolismo , Autoimunidade/genética , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Camundongos , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismoRESUMO
OBJECTIVES: Helicobacter pylori gastritis is considered an infectious disease, regardless of symptoms and stage of disease. Most consensus documents recommend empirical therapy based on local antimicrobial susceptibility patterns. We aimed to provide clinically useful information about primary and secondary antimicrobial resistance to antimicrobials commonly prescribed for H. pylori. METHODS: Overall, 31,406 gastroduodenal biopsies and 2,641 string tests from patients over 15 years of age were plated on selective media, isolating H. pylori in 36.7% of biopsies and 50.7% of string tests. Susceptibility testing could be performed in 96.6% (12,399/12,835) of H. pylori isolates. Polymerase chain reaction (PCR) was also used to detect H. pylori and its resistance to clarithromycin, providing susceptibility data for 112 patients with negative culture results. RESULTS: Resistance to amoxicillin and tetracycline was unusual (0.6% and 0.2%, respectively). Rates of primary resistance to clarithromycin and metronidazole remained steady over the 22-year study period, at around 14% for clarithromycin and 30% for metronidazole, while primary resistance to levofloxacin tripled (from 7.6% in 2000 to 21.7% in 2021, P < 0.001) and increased with patient age. Notably, 1.8% of isolates were multiresistant to clarithromycin, metronidazole, and levofloxacin. Overall, secondary resistance rates were higher (P < 0.0001) than primary resistance rates for clarithromycin (42.5% vs 14.1%), metronidazole (40.9% vs 32%), and levofloxacin (21.5% vs 17.1%). CONCLUSION: Determination of susceptibility for H. pylori by culture and/or PCR in patients undergoing endoscopy could facilitate the implementation of tailored therapy and guide the choice of empirical therapy when susceptibility testing cannot be performed, potentially helping limit the emergence of antimicrobial resistance.
Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos , Claritromicina/farmacologia , Metronidazol , Helicobacter pylori/genética , Levofloxacino , Espanha/epidemiologia , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/tratamento farmacológicoRESUMO
OBJECTIVE: The objective of the study was to determine whether perinatal nicotine exposure adversely affects cardiovascular health in adulthood. STUDY DESIGN: C57Bl/6J female mice were randomized to 200 µg/mL nicotine in 2% saccharin or 2% saccharin alone from 2 weeks before breeding until weaning. Offspring weight, vital signs, and carotid artery vascular reactivity were studied. A second cohort was subjected to shaker stress on day 4 of 7 days. Selected mediators of vascular tone were evaluated by molecular studies. Student t or Mann-Whitney U test was performed for statistical analysis (significance: P < .05). RESULTS: Nicotine-exposed compared with control female offspring had significantly elevated mean blood pressure under normal and stress conditions. Nicotine females lacked heart rate elevation after stress. Nicotine males had higher mean heart rate and a blunted contractile response to phenylephrine compared with controls, without an increase in blood pressure. CONCLUSION: Perinatal nicotine exposure has an impact on the developmental programming of future cardiovascular health, with adverse effects more evident in female offspring.
Assuntos
Pressão Sanguínea/efeitos dos fármacos , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/fisiologia , Nicotina/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Fatores SexuaisRESUMO
Retapamulin in vitro activity against 400 Streptococcus pyogenes clinical isolates obtained from skin, pharynx, ear fluid, and blood samples recovered from 2007 to 2009 was studied. The isolates belonged to 26 different emm types, including isolates nonsusceptible to erythromycin (n=187), tetracycline (n=99), ciprofloxacin (n=59), and bacitracin (n=43). Results were compared to the activities of 16 other antibiotics for topical and systemic use. Retapamulin MICs ranged from ≤0.015 to 0.12 µg/ml, showing the highest intrinsic activity among the topical antimicrobial drugs studied.
Assuntos
Anti-Infecciosos/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Streptococcus pyogenes/efeitos dos fármacos , Bacitracina/farmacologia , Ciprofloxacina/farmacologia , Diterpenos , Eritromicina/farmacologia , Testes de Sensibilidade Microbiana , Tetraciclina/farmacologiaRESUMO
The Escherichia coli heat-labile enterotoxin (LT) possesses a powerful mucosal and systemic adjuvant effect. However, little is known about the cellular and molecular basis of the immunostimulatory activity of LT at the mucosal level, and even less information is available on the mechanisms underlying its systemic adjuvant activity. In this study, we show that distinct mechanisms are responsible for the parenteral and mucosal adjuvanticity of LT. Indeed, the systemic administration of LT upregulates the expression of glucocorticoid-induced TNFR-related protein (GITR), but not other activation markers, in naive T cells. Using WT and GITR-deficient mice and LT and its enzymatically inactive mutant LTK63 as adjuvants, we show that the induction of GITR expression in T cells accounts for the systemic immunostimulatory capacity of LT, which requires an intact enzymatic activity. In contrast, the mucosal administration of LT does not induce GITR expression on Peyer's patche T cells and accordingly no differences are observed in the mucosal adjuvanticity of LT between WT and GITR-deficient mice. Altogether, our results demonstrate the distinct effect of LT after parenteral administration when compared with the mucosal delivery, and describe a new mechanism of LT adjuvanticity related to its ability to induce the expression of GITR in CD4(+) T cells.
Assuntos
Toxinas Bacterianas/imunologia , Linfócitos T CD4-Positivos/imunologia , Enterotoxinas/imunologia , Proteínas de Escherichia coli/imunologia , Imunidade nas Mucosas/imunologia , Ativação Linfocitária/imunologia , Receptores de Fator de Crescimento Neural/imunologia , Receptores do Fator de Necrose Tumoral/imunologia , Adjuvantes Imunológicos , Animais , Anticorpos Antibacterianos/imunologia , Separação Celular , Citometria de Fluxo , Proteína Relacionada a TNFR Induzida por Glucocorticoide , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Receptores de Fator de Crescimento Neural/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
The objective of this study was to investigate vascular function at different ages in a transgenic murine model of fetal vascular programming using a model of uteroplacental insufficiency induced by lack of endothelial nitric oxide synthase. Homozygous NOS3 knockout (KO) and wild-type (WT) mice were cross bred to produce WT, KO, and heterozygous that developed in WT (KOP) or KO (KOM) mothers. Male/female offspring from the four groups were killed at 7, 14, and 21 wk of age (n = 5-10/group), and carotid arteries were used for in vitro vascular studies. Responses to phenylephrine (PE), with/without N(G)-nitro-L-arginine methyl ester (L-NAME), angiotensin (ANG), acetylcholine (ACh), sodium nitroprusside, and isoproterenol (ISO) were studied. At 7 wk, only KO offspring showed higher contractile response to PE, whereas, at 14 and 21 wk, both KO and KOM had a higher response. Incubation with L-NAME abolished these differences. ANG contraction was higher in male KO in all age groups and in 21-wk-old females. Relaxation to ACh and ISO was absent in KO, and significantly decreased in KOM offspring in all age groups compared with KOP and WT, independent of gender. Sodium nitroprusside was not different between groups. The effect of the altered intrauterine environment on the development of abnormal vascular function was limited at 7 wk of age and most evident at 14 wk; further deterioration was limited to ANG-mediated vascular contractility in KO offspring. Our findings provide some hope that at least the first seven postnatal weeks may be an appropriate therapeutic window to prevent cardiovascular disease later in life.
Assuntos
Envelhecimento , Artérias Carótidas/enzimologia , Doenças das Artérias Carótidas/enzimologia , Óxido Nítrico Sintase Tipo III/deficiência , Insuficiência Placentária/enzimologia , Vasoconstrição , Vasodilatação , Fatores Etários , Análise de Variância , Animais , Artérias Carótidas/efeitos dos fármacos , Artérias Carótidas/embriologia , Artérias Carótidas/fisiopatologia , Doenças das Artérias Carótidas/embriologia , Doenças das Artérias Carótidas/genética , Doenças das Artérias Carótidas/fisiopatologia , Doenças das Artérias Carótidas/prevenção & controle , Modelos Animais de Doenças , Progressão da Doença , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Feminino , Desenvolvimento Fetal , Genótipo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Óxido Nítrico Sintase Tipo III/genética , Fenótipo , Insuficiência Placentária/genética , Insuficiência Placentária/fisiopatologia , Gravidez , Fatores Sexuais , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologiaRESUMO
This study examines the effects of VEGF-121 therapy in an animal model of preeclampsia induced by overexpression of soluble VEGF receptor 1 (sVEGFR-1). At day 8 of gestation, CD-1 mice were implanted with subcutaneous osmotic pumps containing either VEGF-121 or vehicle and fitted with telemetric blood pressure (BP) catheters for continuous BP monitoring (days 8-18 of gestation). On day 9, the animals in the VEGF-121 group were randomly allocated for injection with adenovirus carrying sVEGFR-1 or the murine immunoglobulin G2α Fc fragment (mFc) as virus control (Adv-sVEGFR-1; Adv-mFc). Animals in the vehicle group were injected with Adv-sVEGFR-1. On day 18, mice were euthanized, placentas and pups weighted, carotid arteries isolated, and their responses studied in vitro using a wire myograph for isometric tension recording. In mice overexpressing sVEGFR-1, treatment with VEGF-121 significantly reduced BP from days 10 to 18 of gestation compared with that of vehicle. VEGF-sVEGFR-1 animals had significantly higher vasorelaxant response to sodium nitroprusside and significantly lower contractile response to the thromboxane agonist (U-46619) compared with that of the vehicle-sVEGFR-1 mice. Phenylephrine and acetylcholine responses did not significantly vary between the VEGF-sVEGFR-1 and the vehicle-sVEGFR-1 mice. Average pup weight was significantly lower in the vehicle-sVEGFR-1 group compared with the VEGF-sVEGFR-1 and VEGF-mFc groups. In conclusion, VEGF-121 therapy attenuates vascular dysfunction and diminishes intrauterine growth abnormality in an animal model of preeclampsia induced by overexpression of sVEGFR-1. Modulation of VEGF pathway turns into a promising therapeutic approach of preeclampsia.