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OBJECTIVES: Muscle dysmorphia (MD) is a disorder affecting mainly men and is characterized by significant dissatisfaction with muscles. The idea that MD could represent an addiction has been theoretically discussed, but no empirical data are available. Based on Foster et al. (2015) framework, the Addiction to Body Image Inventory (ABII) was developed. This study aims to validate the ABII and to evaluate its capacity to capture MD severity. METHODS: A first community sample of 466 participants was recruited and completed the ABII and questionnaires on MD and body esteem. A second sample of 47 men at risk of MD was recruited mostly in gyms and completed the ABII and questionnaires on MD, eating and psychological symptoms. RESULTS: With the community sample, the results showed that the ABII had a valid factorial structure, good internal consistency, and good convergent validity. With the sample of men at risk of MD, the results showed that the ABII had good convergent validity with MD and eating symptoms but not with psychological symptoms. The results of a regression model showed that the ABII explained 12% of the MD variance. CONCLUSIONS: This study brings the first measure of addiction to body image and suggests that MD must be understood as a complex phenomenon including eating symptoms and addictive tendencies.
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H84T BanLec is a molecularly engineered lectin cloned from bananas with broad-spectrum antiviral activity against several RNA viruses. H84T BanLec dimers bind glycoproteins containing high-mannose N-glycans on the virion envelope, blocking attachment, entry, uncoating, and spread. It was unknown whether H84T BanLec is effective against human herpesviruses varicella-zoster virus (VZV), human cytomegalovirus (HCMV), and herpes simplex virus 1 (HSV-1), which express high-mannose N-linked glycoproteins on their envelopes. We evaluated H84T BanLec against VZV-ORF57-Luc, TB40/E HCMV-fLuc-eGFP, and HSV-1 R8411 in cells, skin organ culture, and mice. The H84T BanLec EC50 was 0.025 µM for VZV (SI50 = 4000) in human foreskin fibroblasts (HFFs), 0.23 µM for HCMV (SI50 = 441) in HFFs, and 0.33 µM for HSV-1 (SI50 = 308) in Vero cells. Human skin was obtained from reduction mammoplasties and prepared for culture. Skin was infected and cultured up to 14 days. H84T BanLec prevented VZV, HCMV and HSV-1 spread in skin at 10 µM in the culture medium, and also exhibited dose-dependent antiviral effects. Additionally, H84T BanLec arrested virus spread when treatment was delayed. Histopathology of HCMV-infected skin showed no overt toxicity when H84T BanLec was present in the media. In athymic nude mice with human skin xenografts (NuSkin mice), H84T BanLec reduced VZV spread when administered subcutaneously prior to intraxenograft virus inoculation. This is the first demonstration of H84T BanLec effectiveness against DNA viruses. H84T BanLec may have additional unexplored activity against other, clinically relevant, glycosylated viruses.
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Antivirais/farmacologia , Citomegalovirus/efeitos dos fármacos , Infecções por Herpesviridae/tratamento farmacológico , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 3/efeitos dos fármacos , Lectinas de Plantas/farmacologia , Dermatopatias Virais/tratamento farmacológico , Pele/virologia , Animais , Chlorocebus aethiops , Citomegalovirus/crescimento & desenvolvimento , Infecções por Herpesviridae/virologia , Herpesvirus Humano 1/crescimento & desenvolvimento , Herpesvirus Humano 3/crescimento & desenvolvimento , Camundongos Nus , Musa/genética , Lectinas de Plantas/genética , Dermatopatias Virais/virologia , Técnicas de Cultura de Tecidos , Células Vero , Replicação Viral/efeitos dos fármacosRESUMO
OBJECTIVE: In the adult brain, neural stem cells (NSCs) located in the subventricular zone (SVZ) produce both neuronal and glial cells. Thyroid hormones (THs) regulate adult NSC differentiation towards a neuronal phenotype, but also have major roles in mitochondrial metabolism. As NSC metabolism relies mainly on glycolysis, whereas mature cells preferentially use oxidative phosphorylation, we studied how THs and mitochondrial metabolism interact on NSC fate determination. METHODS: We used a mitochondrial membrane potential marker in vivo to analyze mitochondrial activity in the different cell types in the SVZ of euthyroid and hypothyroid mice. Using primary adult NSC cultures, we analyzed ROS production, SIRT1 expression, and phosphorylation of DRP1 (a mitochondrial fission mediator) as a function of TH availability. RESULTS: We observed significantly higher mitochondrial activity in cells adopting a neuronal phenotype in vivo in euthyroid mice. However, prolonged hypothyroidism reduced not only neuroblast numbers but also their mitochondrial activity. In vitro studies showed that TH availability favored a neuronal phenotype and that blocking mitochondrial respiration abrogated TH-induced neuronal fate determination. DRP1 phosphorylation was preferentially activated in cells within the neuronal lineage and was stimulated by TH availability. CONCLUSIONS: These results indicate that THs favor NSC fate choice towards a neuronal phenotype in the adult mouse SVZ through effects on mitochondrial metabolism.
Assuntos
Células-Tronco Neurais/metabolismo , Hormônios Tireóideos/metabolismo , Células-Tronco Adultas/citologia , Células-Tronco Adultas/metabolismo , Animais , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dinaminas/metabolismo , Ventrículos Laterais/metabolismo , Masculino , Potencial da Membrana Mitocondrial , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Células-Tronco Neurais/citologia , Neurogênese/efeitos dos fármacos , Neurônios/metabolismo , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Sirtuína 1/metabolismo , Glândula Tireoide/metabolismoRESUMO
OBJECTIVE: In multidisciplinary prenatal diagnosis centers, the search for a tetrasomy 12p mosaic is requested following the discovery of a diaphragmatic hernia in the antenatal period. Thus, the series of Pallister Killian syndromes (PKS: OMIM 601803) probably overestimate the prevalence of diaphragmatic hernia in this syndrome to the detriment of other morphological abnormalities. METHODS: A multicenter retrospective study was conducted with search for assistance from members of the French society for Fetal Pathology. For each identified case, we collected all antenatal and postnatal data. Antenatal data were compared with data from the clinicopathological examination to assess the adequacy of sonographic signs of PKS. A review of the literature on antenatal morphological anomalies in case of PKS completed the study. RESULTS: Ten cases were referred to us: 7 had cytogenetic confirmation and 6 had ultrasound screening. In the prenatal as well as post mortem period, the most common sign is facial dysmorphism (5 cases/6). A malformation of limbs is reported in half of the cases (3 out of 6). Ultrasound examination detected craniofacial dysmorphism in 5 cases out of 6. We found 1 case of left diaphragmatic hernia. Our results are in agreement with the malformation spectrum described in the literature. CONCLUSION: Some malformation associations could evoke a SPK without classical diaphragmatic hernia.
Assuntos
Transtornos Cromossômicos/diagnóstico , Diagnóstico Pré-Natal , Anormalidades Múltiplas/diagnóstico , Transtornos Cromossômicos/genética , Cromossomos Humanos Par 12/genética , Anormalidades Craniofaciais/diagnóstico , Feminino , França , Hérnia Diafragmática/diagnóstico , Humanos , Deformidades Congênitas dos Membros/diagnóstico , Gravidez , Estudos Retrospectivos , Ultrassonografia Pré-NatalRESUMO
DAX1/NR0B1 mutations are responsible for X-linked congenital adrenal hypoplasia (AHC) associated with hypogonadotropic hypogonadism (HH). Few data are available concerning testicular function and fertility in men with DAX1 mutations. Azoospermia as well as failure of gonadotrophin treatment have been reported. We induced spermatogenesis in a patient who has a DAX1 mutation (c.1210C>T), leading to a stop codon in position 404 (p.Gln404X). His endocrine testing revealed a low testosterone level at 1.2 nmol/l (N: 12-40) with low FSH and LH levels at 2.1 IU/l (N: 1-5 IU/l) and 0.1 IU/l (N: 1-4 IU/l), respectively. Baseline semen analysis revealed azoospermia. Menotropin (Menopur(®):150 IU, three times weekly) and human chorionic gonadotrophin (1500 IU, twice weekly) were used. After 20 months of treatment, as azoospermia persisted, bilateral multiple site testicular biopsies were performed. Histology revealed severe hypospermatogenesis. Rare spermatozoa were extracted from the right posterior fragment and ICSI was performed. Four embryos were obtained and, after a frozen-thawed single-embryo transfer, the patient's wife became pregnant and gave birth to a healthy boy. We report the first case of paternity after TESE-ICSI in a patient with DAX1 mutation, giving potential hope to these patients to father non-affected children. Furthermore, this case illustrates the fact that patients with X-linked AHC have a primary testicular defect in addition to HH.
Assuntos
Receptor Nuclear Órfão DAX-1/genética , Hipogonadismo/genética , Infertilidade Masculina/genética , Infertilidade Masculina/terapia , Técnicas de Reprodução Assistida , Hiperplasia Suprarrenal Congênita/genética , Hiperplasia Suprarrenal Congênita/patologia , Hiperplasia Suprarrenal Congênita/fisiopatologia , Hiperplasia Suprarrenal Congênita/terapia , Insuficiência Adrenal , Adulto , Receptor Nuclear Órfão DAX-1/química , Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças Genéticas Ligadas ao Cromossomo X/patologia , Doenças Genéticas Ligadas ao Cromossomo X/fisiopatologia , Doenças Genéticas Ligadas ao Cromossomo X/terapia , Humanos , Hipoadrenocorticismo Familiar , Infertilidade Masculina/tratamento farmacológico , Masculino , Túbulos Seminíferos/citologia , Túbulos Seminíferos/patologia , Espermatogênese/efeitos dos fármacos , Resultado do TratamentoRESUMO
The growth of Nile tilapia Oreochromis niloticus (0.02-20.00 g) was measured when fed to excess during the hours of light, following their exposure to five thermal regimes fluctuating around the thermal optimum for growth (T(opt) = 30 degrees C) over the diel cycle of day (light, L) and night (dark, N), i.e. 27 degrees C(L):33 degrees C(N), 28.5 degrees C(L):31.5 degrees C(N), 30 degrees C(L):30 degrees C(N), 31.5 degrees C(L):28.5 degrees C(N) and 33 degrees C(L):27 degrees C(N) (two replicates per treatment, six weeks' rearing, growth measurements at weekly intervals). A model constructed with a stepwise multiple-regression analysis accounted for 87.4% of the variation of the specific growth rate (G, % M day(-1)) from the variations of wet mass (M), the extent of the thermal fluctuation (F(T)) and their interactions, i.e. log(10)G = 1.7686 - 0.2136 log(10)M + 0.0806 [log (10)Mx log (10) (1 + F(T))] - 0.0394 [log(10)Mx log (10) (1 + F(T))](2). Based on this model, the thermal fluctuation that produces the fastest growth ( , degrees C) decreases in a curvilinear way, from 5.1 degrees C at 20 mg to c. 0.7 degrees C at 20 g. Thermal regimes that produce the slowest growth also produce the highest size heterogeneity. Functional hypotheses behind the size-dependent effects of thermal fluctuations are discussed, together with their implications in natural habitats and aquaculture systems with in different contexts of food availability.
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Tamanho Corporal , Ciclídeos/crescimento & desenvolvimento , Temperatura , Animais , Análise de RegressãoRESUMO
INTRODUCTION: Nitrofurantoin is commonly used in the treatment of urinary tract infection and may cause a potential severe complication: interstitial lung diseases. CASE REPORT: A 78-year-old and an 87-year-old woman treated with nitrofurantoin since respectively 10 months and 6 years developed cough and dyspnea. Antibiotics were ineffective and interstitial lung disease was found. Nitrofurantoin's stopping allowed a clinical and radiological improvement. CONCLUSION: A good medical supervision is important when nitrofurantoin is prescribed for a long time. The treatment has to be stopped when respiratory symptoms appear to allow an improvement of the symptoms.
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Anti-Infecciosos Urinários/efeitos adversos , Doenças Pulmonares Intersticiais/induzido quimicamente , Nitrofurantoína/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Tosse/induzido quimicamente , Dispneia/induzido quimicamente , Feminino , Humanos , Doenças Pulmonares Intersticiais/fisiopatologia , Fluxo Expiratório Máximo/efeitos dos fármacos , Capacidade Pulmonar Total/efeitos dos fármacos , Capacidade Vital/efeitos dos fármacosRESUMO
This paper reports on an experimental study of the splitting instability of an air bubble a few centimetres in diameter placed in a sealed cylindrical cell filled with liquid and submitted to vertical oscillations. The response of the bubble to the oscillations is observed with a high-speed video camera. It is found that the bubble dynamics is closely associated with the acceleration of the cell Gamma. For small acceleration values, the bubble undergoes minor shape deformations. With increasing acceleration values, these deformations are amplified and for sufficiently large Gamma the bubble becomes toroidal. The bubble may then become unstable and split into smaller parts. The onset of bubble division is studied and its dependency on physical parameters such as the fluid viscosity, the fluid surface tension and the initial size of the bubble is presented. It is found that the criterion for the bubble splitting process is associated with a threshold based on the acceleration of the oscillations. Above this threshold, the number of bubbles present in the cell is observed to grow until a final steady state is reached. Data analysis reveals that the final bubble size may be characterized in terms of Bond number.
RESUMO
The p.Val754Met variant, described in 1996 in a CF patient, has been considered a CF mutation. However, biochemical aspects, results of functional studies and, finally, the identification of a complex deletion removing exons 3 to 10 and 14b to 16 in cis of p.Val754Met in a CF patient, argue against a strong deleterious effect. An inventory through the French CF network of patients carrying p.Val754Met led to the registration of seven patients (CF: n=4; idiopathic chronic pancreatitis: n=3) and six healthy individuals, all heterozygous for the variation. Extensive CFTR gene analysis was carried out, including the search for large rearrangements and other possible mutations. The complex deletion, whose breakpoints are described here, was found only in the four CF patients, in association with the same haplotype. This data, added to the fact that the p.[Phe508del]+[Val754Met] genotype was found in a healthy individual, bring further arguments against the association of p.Val754Met with CF. We thus suggest looking for a possible complex allele whenever p.Val754Met is detected and considering it neutral regarding genetic counseling when found in isolation.
Assuntos
Alelos , Aberrações Cromossômicas , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/genética , Adolescente , Adulto , Sequência de Bases , Criança , Fibrose Cística/diagnóstico , Análise Mutacional de DNA , Feminino , Testes Genéticos , Haplótipos , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Polimorfismo Genético , Deleção de SequênciaRESUMO
BACKGROUND: Familial Mediterranean fever (FMF) is the most frequent of the recurrent inherited fevers. This autosomal recessive disorder is characterised by periodic episodes of fever and serositis that commonly affect the people of Arab, Armenian, Sephardic Jewish and Turkish origin. Most of the described MEFV gene anomalies responsible for the disease are missense mutations. In the absence of any functional test, epidemiological studies or pedigree analyses are the only means of proving the deleterious character of these sequence variations. Evidence was provided by our recent study using a population-based approach, that the p.E148Q allele is probably a benign polymorphism and not a disease-causing mutation. Its implication in FMF remains, however, controversial. OBJECTIVE: To evaluate the segregation of the p.E148Q MEFV allele with FMF disease by using pedigree analysis. PARTICIPANTS: 21 patients and 48 unaffected relatives belonging to 18 independent families with FMF. RESULTS: Segregation analysis of the p.E148Q allele was compatible with a Mendelian autosomal recessive transmission of the disease phenotype in only three families. In 15 of 18 families, segregation was partly or completely defective. The p.E148Q allele was not transmitted to 14 of 19 (74%) affected children. CONCLUSIONS: No evidence of preferential transmission of p.E148Q from heterozygous parents to their affected offspring was observed. MEFV is not associated with the clinical manifestations of several patients carrying this variant. Considering p.E148Q to be a benign polymorphism should reduce the possibility of false-positive diagnoses, while highlighting genetic heterogeneity in FMF.
Assuntos
Proteínas do Citoesqueleto/genética , Febre Familiar do Mediterrâneo/genética , Adolescente , Adulto , Alelos , Criança , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo , Polimorfismo Genético , PirinaRESUMO
OBJECTIVE: Familial Mediterranean fever (FMF) is an autosomal-recessive disorder characterized by recurrent attacks of fever, with abdominal, thoracic, or articular pain. FMF is particularly common in Mediterranean populations, while other populations are rarely affected. MEFV gene analysis provides the only objective diagnostic criterion for FMF. However, the spectrum of MEFV mutations, which was first established in classically affected populations, remains insufficiently studied in other populations. The purpose of this study was to assess involvement of MEFV in the phenotype of western European Caucasian patients with a clinical diagnosis of FMF. METHODS: Mutation analysis was performed in 208 Caucasian patients from western Europe, by screening for the most common MEFV mutations in exons 2, 3, 5, and 10, and by sequencing the promoter region and the whole MEFV coding sequence in 21 of these patients. RESULTS: None of the patients carried 2 mutated alleles. Only 2 patients carried 1 mutated allele. CONCLUSION: FMF-like syndromes in western European Caucasian populations cannot be explained by MEFV mutations. These results should be helpful in avoiding laborious and costly MEFV molecular analyses that, at the population level, seem to be of poor diagnostic value in the case of western European Caucasian patients, and rather should prompt a search for other causes in those patients.
Assuntos
Proteínas do Citoesqueleto/genética , Febre Familiar do Mediterrâneo/diagnóstico , Febre Familiar do Mediterrâneo/genética , Testes Genéticos , Mutação , Análise Mutacional de DNA , Europa (Continente) , Febre Familiar do Mediterrâneo/etnologia , Humanos , Fenótipo , Pirina , População Branca/etnologiaRESUMO
Human cytomegalovirus (HCMV) causes a broad spectrum of clinical manifestations in immunocompromised patients, including infection of the gastrointestinal tract. To investigate the role of epithelial cells in the gastrointestinal HCMV disease, we used the intestinal epithelial cell line Caco-2, which is permissive for HCMV replication. In differentiated Caco-2 cells, we showed previously that HCMV infection proceeds preferentially from the basolateral membrane, suggesting that receptors for HCMV may be contained predominantly in the basolateral membrane (A. Esclatine et al., 2000, J. Virol. 74, 513-517). Therefore, we examined expression and localization in Caco-2 cells of heparan sulfate (HS) proteoglycan and annexin II, previously implicated in initial events of HCMV infection. We observed that annexin II is expressed in Caco-2 cells, but is not essential for entry of HCMV. We showed that, during the differentiation process, HS, initially present on the entire surface of the membrane of undifferentiated cells, ultimately became sequestered at the basolateral cell surface of fully differentiated cells. We established by biochemical assays that membrane-associated HS proteoglycan mediates both viral attachment to, and subsequent infection of, Caco-2 cells, regardless of the cell differentiation state. Thus, the redistribution of HS is implicated in the basolateral entry of HCMV into differentiated Caco-2 cells.
Assuntos
Diferenciação Celular/fisiologia , Citomegalovirus/patogenicidade , Enterócitos/metabolismo , Enterócitos/virologia , Heparitina Sulfato/metabolismo , Animais , Anexina A2/metabolismo , Membrana Basal/virologia , Células CACO-2 , Polaridade Celular , Citomegalovirus/fisiologia , Humanos , CamundongosRESUMO
Rotavirus infection is the most common cause of severe infantile gastroenteritis worldwide. In vivo, rotavirus exhibits a marked tropism for the differentiated enterocytes of the intestinal epithelium. In vitro, differentiated and undifferentiated intestinal cells can be infected. We observed that rotavirus infection of the human intestinal epithelial Caco-2 cells induces cytoskeleton alterations as a function of cell differentiation. The vimentin network disorganization detected in undifferentiated Caco-2 cells was not found in fully differentiated cells. In contrast, differentiated Caco-2 cells presented Ca(2+)-dependent microtubule disassembly and Ca(2+)-independent cytokeratin 18 rearrangement, which both require viral replication. We propose that these structural alterations could represent the first manifestations of rotavirus-infected enterocyte injury leading to functional perturbations and then to diarrhea.
Assuntos
Cálcio/metabolismo , Citoesqueleto/ultraestrutura , Enterócitos/virologia , Rotavirus/patogenicidade , Células CACO-2 , Diferenciação Celular , Enterócitos/citologia , Enterócitos/ultraestrutura , Humanos , Rotavirus/fisiologia , Replicação ViralRESUMO
This study compared the efficacy and safety of the fluticasone propionate 125 microg pressurized metered dose inhaler (pMDI) propelled by either hydrofluoroalkane (HFA) 134a or chlorofluorocarbon (CFC) propellants, in adult patients with asthma. HFA 134a is a non-ozone depleting propellant used as a replacement for the CFC propellants 11 and 12 which are being phased out in accordance with the Montreal Protocol. Three hundred and eighty patients with mild to moderate asthma and 'room for improvement' in their treatment were randomized to receive fluticasone propionate 250 microg twice daily via pMDIs propelled by either CFC propellants 11 and 12 (n = 195) or HFA 134a (n = 185). Fluticasone propionate significantly improved lung function over the 4-week treatment period in both treatment groups. The improvement in mean morning peak expiratory flow (PEF) after 7 days of treatment was approximately 12 l min(-1) in both groups, rising to approximately 22 l min(-1) at the end of the 4-week treatment period. The adjusted mean difference between the two formulations over weeks 1-4 was -1 l min(-1) (90% confidence interval: -7, 5 l min(-1)), confirming their equivalence. Clinical comparability was also demonstrated with respect to secondary efficacy variables, including daily symptom scores, evening PEF and clinic visit expiratory measurements. There were no clinically relevant differences in adverse events or serum cortisol levels between the two groups. The fluticasone propionate 125 microg HFA 134a pMDI is an effective and well tolerated product and is a suitable replacement for the fluticasone propionate 125 microg CFC pMDI at a microgram equivalent dose.
Assuntos
Propelentes de Aerossol/farmacocinética , Androstadienos/administração & dosagem , Antiasmáticos/administração & dosagem , Asma/tratamento farmacológico , Hidrocarbonetos Fluorados/farmacocinética , Administração por Inalação , Adolescente , Adulto , Propelentes de Aerossol/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Clorofluorcarbonetos/efeitos adversos , Clorofluorcarbonetos/farmacocinética , Método Duplo-Cego , Feminino , Fluticasona , Volume Expiratório Forçado/fisiologia , Humanos , Hidrocarbonetos Fluorados/efeitos adversos , Hidrocortisona/sangue , Masculino , Pessoa de Meia-Idade , Pico do Fluxo Expiratório/fisiologia , Equivalência Terapêutica , Resultado do TratamentoRESUMO
Rotaviruses, which infect mature enterocytes of the small intestine, are recognized as the most important cause of viral gastroenteritis in young children. We have previously reported that rotavirus infection induces microvillar F-actin disassembly in human intestinal epithelial Caco-2 cells (N. Jourdan, J. P. Brunet, C. Sapin, A. Blais, J. Cotte-Laffitte, F. Forestier, A. M. Quero, G. Trugnan, and A. L. Servin, J. Virol. 72:7228-7236, 1998). In this study, to determine the mechanism responsible for rotavirus-induced F-actin alteration, we investigated the effect of infection on intracellular calcium concentration ([Ca(2+)](i)) in Caco-2 cells, since Ca(2+) is known to be a determinant factor for actin cytoskeleton regulation. As measured by quin2 fluorescence, viral replication induced a progressive increase in [Ca(2+)](i) from 7 h postinfection, which was shown to be necessary and sufficient for microvillar F-actin disassembly. During the first hours of infection, the increase in [Ca(2+)](i) was related only to an increase in Ca(2+) permeability of plasmalemma. At a late stage of infection, [Ca(2+)](i) elevation was due to both extracellular Ca(2+) influx and Ca(2+) release from the intracellular organelles, mainly the endoplasmic reticulum (ER). We noted that at this time the [Ca(2+)](i) increase was partially related to a phospholipase C (PLC)-dependent mechanism, which probably explains the Ca(2+) release from the ER. We also demonstrated for the first time that viral proteins or peptides, released into culture supernatants of rotavirus-infected Caco-2 cells, induced a transient increase in [Ca(2+)](i) of uninfected Caco-2 cells, by a PLC-dependent efflux of Ca(2+) from the ER and by extracellular Ca(2+) influx. These supernatants induced a Ca(2+)-dependent microvillar F-actin alteration in uninfected Caco-2 cells, thus participating in rotavirus pathogenesis.
Assuntos
Actinas/metabolismo , Células CACO-2/virologia , Cálcio/metabolismo , Rotavirus , Retículo Endoplasmático/metabolismo , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/virologia , Humanos , Microvilosidades/metabolismo , Fosfolipases Tipo C/metabolismo , Proteínas Virais/farmacologia , Replicação ViralRESUMO
Human cytomegalovirus (CMV) causes severe disease in immunosuppressed patients and notably infects the gastrointestinal tract. To understand the interaction of CMV with intestinal epithelial cells, which are highly susceptible to CMV infection in vivo, we used the intestinal epithelial cell line Caco-2 and demonstrated that CMV enters predominantly through the basolateral surface of polarized Caco-2 cells. As shown by expression of all three classes of CMV proteins and by visualization of nucleocapsids by transmission electron microscopy, both poorly and fully differentiated Caco-2 cells were permissive to CMV replication. However, infection failed to produce infectious particles in Caco-2 cells, irrespective of the state of differentiation.
Assuntos
Diferenciação Celular , Citomegalovirus/patogenicidade , Mucosa Intestinal/virologia , Antígenos Virais/imunologia , Membrana Basal/virologia , Células CACO-2 , Citomegalovirus/metabolismo , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/ultraestrutura , Microscopia Eletrônica , Nucleocapsídeo/biossínteseRESUMO
The in vivo role of endogenous interleukin 12 (IL-12) in modulating intrapulmonary growth of Legionella pneumophila was assessed by using a murine model of replicative L. pneumophila lung infection. Intratracheal inoculation of A/J mice with virulent bacteria (10(6) L. pneumophila cells per mouse) resulted in induction of IL-12, which preceded clearance of the bacteria from the lung. Inhibition of endogenous IL-12 activity, via administration of IL-12 neutralizing antiserum, resulted in enhanced intrapulmonary growth of the bacteria within 5 days postinfection (compared to untreated L. pneumophila-infected mice). Because IL-12 has previously been shown to modulate the expression of cytokines, including gamma interferon (IFN-gamma), tumor necrosis factor alpha (TNF-alpha), and IL-10, which regulate L. pneumophila growth, immunomodulatory effects of endogenous IL-12 on intrapulmonary levels of these cytokines during replicative L. pneumophila lung infection were subsequently assessed. Results of these experiments demonstrated that TNF-alpha activity was significantly lower, while protein levels of IFN-gamma and IL-10 in the lung were similar, in L. pneumophila-infected mice administered IL-12 antiserum, compared to similarly infected untreated mice. Together, these results demonstrate that IL-12 is critical for resolution of replicative L. pneumophila lung infection and suggest that regulation of intrapulmonary growth of L. pneumophila by endogenous IL-12 is mediated, at least in part, by TNF-alpha.
Assuntos
Interleucina-12/imunologia , Interleucina-12/metabolismo , Legionella pneumophila/crescimento & desenvolvimento , Doença dos Legionários/imunologia , Animais , Líquido da Lavagem Broncoalveolar/imunologia , Feminino , Interferon gama/imunologia , Interferon gama/metabolismo , Interleucina-10/imunologia , Interleucina-10/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos , Testes de Neutralização , Organismos Livres de Patógenos Específicos , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Peritoneal macrophages (PM) were isolated from mice treated with Dimycolate of Trehalose (TDM), a glycolipid extracted from the cell wall of Mycobacterium tuberculosis. PM from TDM-treated mice (TDM-PM) were shown to secrete consistent amount of IFN-gamma, which was not detectable in control Resident-PM (Res-PM), as revealed by ELISA. In addition, biologically active IFN was detected in the supernatants of TDM-PM, whereas no IFN production was found in those of control Res-PM. The addition of specific antisera to PM cultures revealed the simultaneous production of both type I and II IFNs in TDM-PM cultures. No reciprocal regulation in the production of IFN-gamma and IFN-alpha/beta was found in these cultures. In parallel, nitric oxide (NO) production was measured in TDM-PM cultures by detecting nitrites (NO2-). TDM-PM cultures accumulated high amounts of NO2- which decreased to the level of Res-PM in the presence of NMMA, an inhibitor of NO-synthases. In vitro, neither type I nor type II IFNs were involved in the stimulation of NO production. The capacity of macrophages to simultaneously secrete IFN-gamma, IFN-alpha/beta and NO upon in vivo TDM-treatment could be of particular relevance for the defense process of innate immunity in which macrophages play a crucial role.
Assuntos
Fatores Corda/farmacologia , Interferon-alfa/biossíntese , Interferon beta/biossíntese , Interferon gama/biossíntese , Macrófagos Peritoneais/metabolismo , Óxido Nítrico/biossíntese , Animais , Células Cultivadas , Feminino , Camundongos , RatosRESUMO
Legionella pneumophila is a bacterial parasite of many species of freshwater protozoa and occasionally an intracellular pathogen of humans. While protozoa are known to play a key role in the persistence of L. pneumophila in the environment, there has been limited research addressing the potential role of L. pneumophila-infected protozoa in the pathogenesis of human infection. In this report, the potential role of an L. pneumophila-infected amoeba as an infectious particle in replicative L. pneumophila lung infection was investigated in vivo with the amoeba Hartmannella vermiformis, a natural reservoir of L. pneumophila in the environment. L. pneumophila-infected H. vermiformis organisms were prepared by coculture of the amoebae and virulent L. pneumophila cells in vitro. A/J mice, which are susceptible to replicative L. pneumophila lung infection, were subsequently inoculated intratracheally with L. pneumophila-infected H. vermiformis organisms (10(6) amoebae containing 10(5) bacteria), and intrapulmonary growth of the bacteria was assessed. A/J mice inoculated intratracheally with L. pneumophila-infected H. vermiformis organisms developed replicative L. pneumophila lung infections. Furthermore, L. pneumophila-infected H. vermiformis organisms were more pathogenic than an equivalent number of bacteria or a coinoculum of L. pneumophila cells and uninfected amoebae. These results demonstrate that L. pneumophila-infected amoebae are infectious particles in replicative L. pneumophila infections in vivo and support the hypothesis that inhaled protozoa may serve as cofactors in the pathogenesis of pulmonary disease induced by inhaled respiratory pathogens.
Assuntos
Hartmannella/microbiologia , Hartmannella/parasitologia , Legionella pneumophila , Doença dos Legionários/microbiologia , Doença dos Legionários/parasitologia , Animais , Modelos Animais de Doenças , Humanos , Doença dos Legionários/transmissão , Pulmão/microbiologia , Pulmão/parasitologia , CamundongosRESUMO
The potential role of inhaled protozoa as a niche for intrapulmonary replication of Legionella pneumophila was investigated in vivo with mutant strains of L. pneumophila which have reduced virulence for the amoeba Hartmannella vermiformis. L. pneumophila AA488 and AA502 were derived from wild-type strain AA100 after transposon mutagenesis. These mutants have reduced virulence for H. vermiformis but are fully virulent for mononuclear phagocytic cells. A/J mice, which are susceptible to replicative L. pneumophila lung infections, were inoculated intratracheally with L. pneumophila AA100, AA488, or AA502 (10[6] bacteria per mouse) or were coinoculated with one of the L. pneumophila strains (10[6] bacteria per mouse) and uninfected H. vermiformis (10[6] amoebae per mouse). The effect of coinoculation with H. vermiformis on intrapulmonary growth of each L. pneumophila strain was subsequently assessed. In agreement with our previous studies, coinoculation with H. vermiformis significantly enhanced intrapulmonary growth of the parent L. pneumophila strain (AA100). In contrast, intrapulmonary growth of L. pneumophila AA488 or AA502 was not significantly enhanced by coinoculation of mice with H. vermiformis. These studies demonstrate that L. pneumophila virulence for amoebae is required for maximal intrapulmonary growth of the bacteria in mice coinoculated with H. vermiformis and support the hypothesis that inhaled amoebae may potentiate intrapulmonary growth of L. pneumophila by providing a niche for bacterial replication.