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1.
Appl Opt ; 56(2): 330-335, 2017 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-28085872

RESUMO

In this work, we report on the analysis of speckle patterns produced by illuminating different rough surfaces with an optical vortex, a first-order (l=1) Laguerre-Gaussian beam. The generated speckle patterns were observed in the normal direction exploring four different planes: the diffraction plane, image plane, focal plane, and exact Fourier transform plane. The digital speckle patterns were analyzed using the Hurst exponent of digital images, an interesting tool used to study surface roughness. We show a proof of principle that the Hurst exponent of a digital speckle pattern is more sensitive with respect to the surface roughness when the speckle pattern is produced by an optical vortex and observed at a focal plane. We also show that Hurst exponents are not so sensitive with respect to the topological charge l. These results open news possibilities of investigation into speckle metrology once we have several techniques that use speckle patterns for different applications.

2.
Scand J Immunol ; 75(2): 142-6, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21923739

RESUMO

Sporotrichosis is a chronic granulomatous mycosis caused by the dimorphic fungus Sporothrix schenckii. The immunological mechanisms involved in the prevention and control of sporotrichosis suggest that cell-mediated immunity plays an important role in protecting the host against S. schenckii. Nonetheless, recent data strongly support the existence of protective Abs against this pathogenic fungus. In a previous study, we showed that passive Ab therapy led to a significant reduction in the number of colony forming unit in the organs of mice when the MAb was injected before and during S. schenckii infection. The ability of opsonization to enhance macrophage damage to S. schenckii and subsequent cytokine production was investigated in this work. Here we show that the fungicidal characteristics of macrophages are increased when the fungus is phagocytosed in the presence of inactivated serum from mice infected with S. schenckii or mAb anti-gp70. Additionally, we show an increase in the levels of pro-inflammatory cytokines such as TNF-α and IL-1ß. This study provides additional support for the importance of antibodies in protecting against S. schenckii and concludes that opsonization is an important process to increase TNF-α production and fungus killing by macrophages in experimental sporotrichosis.


Assuntos
Anticorpos Antifúngicos/farmacologia , Macrófagos/efeitos dos fármacos , Proteínas Opsonizantes/farmacologia , Fagocitose/efeitos dos fármacos , Sporothrix/imunologia , Esporotricose/imunologia , Fator de Necrose Tumoral alfa/biossíntese , Animais , Anticorpos Antifúngicos/isolamento & purificação , Linhagem Celular , Feminino , Soros Imunes/química , Imunidade Celular/efeitos dos fármacos , Interleucina-1beta/biossíntese , Macrófagos/imunologia , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Viabilidade Microbiana , Proteínas Opsonizantes/isolamento & purificação , Esporotricose/microbiologia , Esporotricose/patologia
3.
Braz J Med Biol Res ; 55: e12036, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35976269

RESUMO

The study of functional reorganization following stroke has been steadily growing supported by advances in neuroimaging techniques, such as functional magnetic resonance imaging (fMRI). Concomitantly, graph theory has been increasingly employed in neuroscience to model the brain's functional connectivity (FC) and to investigate it in a variety of contexts. The aims of this study were: 1) to investigate the reorganization of network topology in the ipsilesional (IL) and contralesional (CL) hemispheres of stroke patients with (motor stroke group) and without (control stroke group) motor impairment, and 2) to predict motor recovery through the relationship between local topological variations of the functional network and increased motor function. We modeled the brain's FC as a graph using fMRI data, and we characterized its interactions with the following graph metrics: degree, clustering coefficient, characteristic path length, and betweenness centrality (BC). For both patient groups, BC yielded the largest variations between the two analyzed time points, especially in the motor stroke group. This group presented significant correlations (P<0.05) between average BC changes and the improvements in upper-extremity Fugl-Meyer (UE-FM) scores at the primary sensorimotor cortex and the supplementary motor area for the CL hemisphere. These regions participate in processes related to the selection, planning, and execution of movement. Generally, higher increases in average BC over these areas were related to larger improvements in UE-FM assessment. Although the sample was small, these results suggest the possibility of using BC as an indication of brain plasticity mechanisms following stroke.


Assuntos
Córtex Motor , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Imageamento por Ressonância Magnética/métodos , Córtex Motor/diagnóstico por imagem , Córtex Motor/patologia , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/diagnóstico por imagem , Extremidade Superior
4.
Case Rep Urol ; 2021: 9981381, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34603815

RESUMO

INTRODUCTION: The genitourinary system is a recognized site for multiple primary malignant neoplasms even without syndromic anomalies. However, to the best of our knowledge, a case of upper tract urothelial carcinoma (UTUC) with contralateral renal cell carcinoma (RCC) is not reported in surgical literature so far. Case Presentation. A 52-year-old Sri Lankan male patient was found to have a right lower ureteric tumour and a left renal mass together upon investigating for painless visible hematuria. The right ureteric tumour measured 32 × 22 mm resulting in moderate hydronephrosis and cortical thinning of the right kidney, and the left renal mass measured 43 × 38 mm involving the lower pole. The biopsy of the right ureteric lesion revealed a high-grade transitional cell carcinoma with focal nested pattern and that of the left renal mass revealed a clear cell carcinoma. Right nephroureterectomy followed by a left partial nephrectomy was performed in six weeks' interval. The histology of both the resected specimens confirmed the biopsy findings. Discussion. A high-risk upper tract urothelial carcinoma such as the right ureteric tumour of this patient required a nephroureterectomy which makes the management of the contralateral renal cell carcinoma more complex. An adequate functional renal remnant was ensured after offering oncologically sound surgical treatment for both the malignancies of this patient. CONCLUSION: A UTUC when associated with a contralateral RCC poses challenges in patient management. The preservation of renal excretory function has to be considered as an important determinant in addition to oncologically sound surgical resection when managing complex cases of genitourinary malignancies involving both sides of the upper urinary tract.

5.
Toxicology ; 241(1-2): 47-57, 2007 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-17897770

RESUMO

Hydroquinone (HQ) is naturally found in the diet, drugs, as an environmental contaminant and endogenously generated after benzene exposure. Considering that HQ alters the immune system and its several source of exposures in the environment, we hypothesized that prolonged exposure of HQ could affect the course of an immune-mediated inflammatory response. For this purpose, male Wistar rats were intraperitoneally exposed to vehicle or HQ once a day, for 22 days with a 2-day interval every 5 days. On day 10 after exposure with vehicle or HQ, animals were ovalbumin (OA)-sensitized and OA-aerosolized challenged on day 23. HQ exposure did not alter the number of circulating leukocytes but impaired allergic inflammation, evidenced by lower number of leukocytes in the bronchoalveolar lavage fluid 24h after OA-challenge. Reduced force contraction of ex vivo tracheal segments upon OA-challenge and impaired mesentery mast cell degranulation after in situ OA-challenge were also detected in tissues from HQ exposed animals. The OA-specificity on the decreased responses was corroborated by normal trachea contraction and mast cell degranulation in response to compound 48/80. In fact, lower levels of circulating OA-anaphylactic antibodies were found in HQ exposed rats, as assessed by passive cutaneous anaphylaxis assay. The reduced level of OA-anaphylactic antibody was not dependent on lower number or proliferation of lymphocytes. Nevertheless, lower expression of the co-stimulatory molecules CD6 and CD45R on OA-activated lymphocytes from HQ exposed rats indicate the interference of HQ exposure with signaling of the humoral response during allergic inflammation. Together, these data indicate specific effects of HQ exposure manifested during an immune host defense.


Assuntos
Alveolite Alérgica Extrínseca/patologia , Poluentes Ambientais/toxicidade , Hidroquinonas/toxicidade , Alveolite Alérgica Extrínseca/fisiopatologia , Animais , Antígenos CD/biossíntese , Antígenos de Diferenciação de Linfócitos T/biossíntese , Líquido da Lavagem Broncoalveolar/citologia , Degranulação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Citometria de Fluxo , Antígenos Comuns de Leucócito/biossíntese , Contagem de Leucócitos , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Masculino , Mastócitos/efeitos dos fármacos , Mastócitos/ultraestrutura , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Infiltração de Neutrófilos/efeitos dos fármacos , Ovalbumina/imunologia , Anafilaxia Cutânea Passiva/imunologia , Ratos , Ratos Wistar , Baço/efeitos dos fármacos , Baço/patologia , Traqueia/efeitos dos fármacos , Traqueia/fisiologia
6.
Vet Microbiol ; 121(3-4): 257-67, 2007 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-17267142

RESUMO

The ability of alphaherpesviruses to infect different ruminant species may have important implications for control/eradication efforts. Serological data indicate that goats may be naturally infected with bovine herpesviruses. To investigate the susceptibility of goats to bovine herpesvirus-5 (BoHV-5), 3-4-month-old kids were inoculated intranasally with each of three Brazilian BoHV-5 isolates (G1, n=8; G2, n=5; G3, n=5). The acute infection was characterized by virus shedding in nasal secretions for up to 14 days (titers up to 10(5.97)TCID(50)/mL), mild respiratory signs and conjunctivitis. All animals seroconverted to BoHV-5, developing virus neutralizing (VN) titers from 4 to 32 to the homologous viruses. At day 60 post inoculation (pi), two animals from each group were euthanized for tissue collection and the remaining goats were submitted to dexamethasone administration (0.4 mg kg(-1) for 5 days). Dexamethasone treatment resulted in virus reactivation in 9 out of 12 animals, as ascertained by virus shedding and/or by increase in VN titers. Virus shedding was detected in 8/12 animals and lasted from 1 to 9 days. Latent viral DNA was detected by PCR in the olfactory bulb and/or trigeminal ganglia of 6/6 goats euthanized at day 60 pi and in 12/12 animals euthanized 40 days post-dexamethasone. These results show that young goats are susceptible to BoHV-5 and may shed virus upon reactivation of latent infection. Thus, it is reasonable to expect that goats raised in close contact with cattle in areas where BoHV-5 is endemic may be infected and therefore should be considered potential reservoirs of the virus.


Assuntos
Encefalite Viral/veterinária , Encefalite Viral/virologia , Doenças das Cabras/virologia , Infecções por Herpesviridae/veterinária , Infecções por Herpesviridae/virologia , Herpesvirus Bovino 5/fisiologia , Meningoencefalite/veterinária , Animais , Anticorpos Antivirais/sangue , DNA Viral/química , DNA Viral/genética , Dexametasona/farmacologia , Encefalite Viral/imunologia , Glucocorticoides/farmacologia , Doenças das Cabras/imunologia , Cabras , Infecções por Herpesviridae/imunologia , Herpesvirus Bovino 5/genética , Herpesvirus Bovino 5/crescimento & desenvolvimento , Meningoencefalite/imunologia , Meningoencefalite/virologia , Mucosa Nasal/virologia , Testes de Neutralização/veterinária , Reação em Cadeia da Polimerase/veterinária , Distribuição Aleatória , Latência Viral , Eliminação de Partículas Virais/imunologia
7.
Braz. j. med. biol. res ; 55: e12036, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1394129

RESUMO

The study of functional reorganization following stroke has been steadily growing supported by advances in neuroimaging techniques, such as functional magnetic resonance imaging (fMRI). Concomitantly, graph theory has been increasingly employed in neuroscience to model the brain's functional connectivity (FC) and to investigate it in a variety of contexts. The aims of this study were: 1) to investigate the reorganization of network topology in the ipsilesional (IL) and contralesional (CL) hemispheres of stroke patients with (motor stroke group) and without (control stroke group) motor impairment, and 2) to predict motor recovery through the relationship between local topological variations of the functional network and increased motor function. We modeled the brain's FC as a graph using fMRI data, and we characterized its interactions with the following graph metrics: degree, clustering coefficient, characteristic path length, and betweenness centrality (BC). For both patient groups, BC yielded the largest variations between the two analyzed time points, especially in the motor stroke group. This group presented significant correlations (P<0.05) between average BC changes and the improvements in upper-extremity Fugl-Meyer (UE-FM) scores at the primary sensorimotor cortex and the supplementary motor area for the CL hemisphere. These regions participate in processes related to the selection, planning, and execution of movement. Generally, higher increases in average BC over these areas were related to larger improvements in UE-FM assessment. Although the sample was small, these results suggest the possibility of using BC as an indication of brain plasticity mechanisms following stroke.

8.
Microbes Infect ; 8(2): 372-9, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16293438

RESUMO

Trichophyton rubrum is the most common pathogen causing dermatophytosis, accounting for approximately 80% of the reported cases of onychomycosis. Since 90% of the chronic dermatophyte infections are caused by T. rubrum, it is likely that this pathogen must have evolved mechanisms that evade or suppress cell-mediated immunity. Several reports have highlighted the participation of phagocytes in the immune defense against fungi; however, few studies have addressed the role of these cells in dermatophytosis. In this study, we investigated the interactions of resident and peritoneal macrophages with T. rubrum. We show here that the interaction of T. rubrum conidia with resident macrophages results in the production of TNF-alpha and IL-10 but not IL-12 and nitric oxide. Infected macrophages down-regulated the expression of co-stimulatory molecules (CD80 and CD54). We also show that phagocytosis of T. rubrum conidia is inhibited by the addition of fungal exoantigens or mannan. Cytotoxicity assays indicated that after 8 h of conidia ingestion macrophage viability decreased drastically. Electron microscopy revealed that the ingested conidia grow and differentiate into hyphae inside macrophages leading to rupture of the macrophage membrane.


Assuntos
Morte Celular , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Macrófagos/microbiologia , Trichophyton/patogenicidade , Animais , Citocinas/metabolismo , Feminino , Humanos , Interleucina-10/metabolismo , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/microbiologia , Camundongos , Fagocitose , Trichophyton/crescimento & desenvolvimento , Fator de Necrose Tumoral alfa/metabolismo
9.
Surg Endosc ; 17(9): 1356-61, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12811663

RESUMO

BACKGROUND: The real incidence of bile duct injury (BDI) during laparoscopic cholecystectomy (LC) is not known. METHODS: Using questionnaires, we analyzed 91,232 LC performed by 170 surgical units in Brazil between 1990 and 1997. RESULTS: A total of 167 BDI occurred (0.18%); the most frequent were Bismuth type 1 injuries (67.7%). Most injuries (56.8%) occurred at the hands of surgeons who had surpassed the learning curve (50 operations). However, the incidence dropped with increasing experience; it was 0.77% at surgical departments with <50 operations vs 0.16% at departments with >500 operations. The diagnosis was made intraoperatively in 67.7%, but it was based on intraoperative cholangiography in only 19.5%. The procedure was converted to open surgery in 85.8% when the diagnosis of injury occurred intraoperatively, and laparotomy was performed in 90.7% when the injury was diagnosed postoperatively. The mean hospitalization time was 7.6 +/- 5.9 days, the major complications were stenosis and fistulas, and the mortality rate was 4.2%. CONCLUSION: The incidence of BDI after LC is similar to that reported for the open procedure. BDI increases mortality and morbidity and prolongs hospitalization; therefore, all efforts should be made to reduce its incidence.


Assuntos
Ductos Biliares/lesões , Colecistectomia Laparoscópica , Complicações Intraoperatórias/etiologia , Anastomose Cirúrgica , Fístula Biliar/epidemiologia , Fístula Biliar/etiologia , Brasil/epidemiologia , Colangiografia , Colecistectomia Laparoscópica/estatística & dados numéricos , Competência Clínica , Ducto Colédoco/lesões , Constrição Patológica , Ducto Cístico/lesões , Ducto Hepático Comum/lesões , Mortalidade Hospitalar , Humanos , Doença Iatrogênica , Incidência , Cuidados Intraoperatórios , Complicações Intraoperatórias/diagnóstico , Complicações Intraoperatórias/epidemiologia , Complicações Intraoperatórias/cirurgia , Aprendizagem , Tempo de Internação/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Fatores de Risco , Inquéritos e Questionários
10.
Braz J Med Biol Res ; 34(4): 529-37, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11285466

RESUMO

In the present study we evaluated T cell proliferation and Th lymphokine patterns in response to gp43 from Paracoccidioides brasiliensis presented by isolated dendritic cells from susceptible and resistant mice. T cell proliferation assays showed that dendritic cells from susceptible mice were less efficient than those from resistant mice. The pattern of T cell lymphokines stimulated by dendritic cells was always Th1, although the levels of IL-2 and IFN-gamma were lower in T cell cultures from susceptible mice. To determine whether different antigen-presenting cells such as macrophages and dendritic cells stimulated different concentrations of Th1 lymphokines, the production of IFN-gamma and IL-2 was measured. It was observed that dendritic cells were more efficient than macrophages in stimulating lymphoproliferation in resistant mice. However, no significant difference was observed for IFN-gamma or IL-2 production. When cells from susceptible mice were used, macrophages were more efficient in stimulating lymphoproliferation than dendritic cells, but no difference was observed in the production of Th1 cytokine. Taken together, these results suggest the lower efficiency of dendritic cells and macrophages from B10.A mice in stimulating T cells that secrete Th1 lymphokines in vitro, an effect that may be involved in the progression of the disease in vivo.


Assuntos
Células Dendríticas/imunologia , Proteínas Fúngicas , Linfocinas/imunologia , Macrófagos/imunologia , Paracoccidioides/imunologia , Células Th1/imunologia , Animais , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/fisiologia , Antígenos de Fungos/imunologia , Divisão Celular , Suscetibilidade a Doenças , Feminino , Glicoproteínas/imunologia , Glicoproteínas/isolamento & purificação , Linfocinas/análise , Camundongos , Camundongos Endogâmicos A , Paracoccidioides/citologia , Paracoccidioidomicose/imunologia , Baço/citologia , Linfócitos T/citologia , Linfócitos T/imunologia , Células Th1/citologia
11.
Food Res Int ; 64: 283-288, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30011652

RESUMO

Functional foods are important sources of probiotic delivery, mainly by fermented milk products. The physiological benefits attributed to bifido bacteria are their abilities to interfere with the adhesion of pathogenic species to surfaces of intestinal cells, and to enhance the host's immune function through their metabolic activities. However, the effects of a technological approach - fermentation or addition of probiotic in milk, and its efficacy in health are rarely taken into consideration. Hence, fermented or unfermented milk using Bifidobacterium animalis subsp. lactis HN019 were administered to BALB/c mice for 14days. After that, the architecture of the gut was histologically investigated, and the related immune cells were examined by flow cytometry and immunofluorescence. Increase in mucus and cellularity production, changes in immune pattern and preservation of mucosal epithelia in health BALB/c mice were observed only in the fermented milk group. This suggested that changes in functionality of bifidobacteria and/or the metabolites produced by the fermentation process are the keys to improving beneficial effects in the host of the gut mucosa.

12.
Clin Vaccine Immunol ; 19(1): 23-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22089247

RESUMO

Vaccination with peptide 10 (P10), derived from the Paracoccidioides brasiliensis glycoprotein 43 (gp43), induces a Th1 response that protects mice in an intratracheal P. brasiliensis infection model. Combining P10 with complete Freund's adjuvant (CFA) or other adjuvants further increases the peptide's antifungal effect. Since dendritic cells (DCs) are up to 1,000-fold more efficient at activating T cells than CFA, we examined the impact of P10-primed bone-marrow-derived DC vaccination in mice. Splenocytes from mice immunized with P10 were stimulated in vitro with P10 or P10-primed DCs. T cell proliferation was significantly increased in the presence of P10-primed DCs compared to the peptide. The protective efficacy of P10-primed DCs was studied in an intratracheal P. brasiliensis model in BALB/c mice. Administration of P10-primed DCs prior to (via subcutaneous vaccination) or weeks after (via either subcutaneous or intravenous injection) P. brasiliensis infection decreased pulmonary damage and significantly reduced fungal burdens. The protective response mediated by the injection of primed DCs was characterized mainly by an increased production of gamma interferon (IFN-γ) and interleukin 12 (IL-12) and a reduction in IL-10 and IL-4 compared to those of infected mice that received saline or unprimed DCs. Hence, our data demonstrate the potential of P10-primed DCs as a vaccine capable of both the rapid protection against the development of serious paracoccidioidomycosis or the treatment of established P. brasiliensis disease.


Assuntos
Células Dendríticas/imunologia , Vacinas Fúngicas/imunologia , Glicoproteínas/imunologia , Paracoccidioides/imunologia , Paracoccidioidomicose/prevenção & controle , Paracoccidioidomicose/terapia , Fragmentos de Peptídeos/imunologia , Vacinação/métodos , Animais , Proliferação de Células , Citocinas/metabolismo , Vacinas Fúngicas/administração & dosagem , Pulmão/microbiologia , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Linfócitos T/imunologia , Vacinas de Subunidades Antigênicas/administração & dosagem , Vacinas de Subunidades Antigênicas/imunologia
13.
Anat Histol Embryol ; 40(2): 128-33, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21138465

RESUMO

The presence of lingual papillae and the nerve endings in the middle region of the tongue mucosa of collared peccary (Tayassu tajacu) were studied using scanning electron microscopy and light microscopy, based upon the silver impregnation method. The middle region of tongue mucosa revealed numerous filiform and fungiform papillae. The thick epithelial layer showed epithelial cells and a dense connective tissue layer containing nerve fibre bundles and capillaries. The sensory nerve endings, intensely stained by silver impregnation, were usually non-encapsulated and extended into the connective tissue of the filiform and fungiform papillae very close to the epithelial cells. In some regions, the sensory nerves fibres formed a dense and complex network of fine fibrils. The presence of these nerve fibrils may characterize the mechanisms of transmission of sensitive impulses to the tongue mucosa.


Assuntos
Gengiva/ultraestrutura , Mamíferos/anatomia & histologia , Terminações Nervosas/ultraestrutura , Língua/ultraestrutura , Animais , Tecido Conjuntivo/irrigação sanguínea , Tecido Conjuntivo/inervação , Células Epiteliais , Feminino , Gengiva/inervação , Masculino , Microscopia Eletrônica de Varredura , Coloração pela Prata/métodos , Língua/inervação
14.
Res Vet Sci ; 87(1): 161-6, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19157471

RESUMO

The biology of latent infection by bovine herpesvirus 2 (BoHV-2), the agent of mammillitis in cows, remains largely unknown. We herein report attempts to reactivate the latent infection and investigated the sites of BoHV-2 latency in experimentally infected sheep. Ewes inoculated with BoHV-2 in the udder's skin shed virus for up to five days, developed mammillitis and seroconverted. However, attempts to reactivate latent infection by dexamethasone administration at day 40 pi failed. Nevertheless, viral DNA--and not infectious virus--was detected by PCR in several nerve ganglia and/or regional lymph nodes (LNs) of all animals at day 40 post-reactivation. Likewise, lambs previously inoculated with BoHV-2 in the nose harbored latent viral DNA in trigeminal ganglia, tonsils and regional LNs. These results demonstrate that BoHV-2 establishes latent infection in nerve ganglia and in regional lymphoid tissues, yet virus reactivation is not easily achieved by standard protocols used.


Assuntos
DNA Viral/isolamento & purificação , Herpes Simples/veterinária , Herpesvirus Bovino 2/genética , Doenças dos Ovinos/virologia , Animais , DNA Viral/metabolismo , Feminino , Herpes Simples/virologia , Lactação , Ovinos , Distribuição Tecidual , Latência Viral , Eliminação de Partículas Virais
15.
Scand J Immunol ; 64(6): 595-600, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17083615

RESUMO

Chromoblastomycosis is a human chronic, often debilitating, suppurative, granulomatus mycosis of the skin and subcutaneous tissues beginning after inoculation trauma. It occurs worldwide, but is more frequently observed in tropical countries such as Brazil. Some studies have focused on fungus-host interaction, showing a predominantly cell-mediated immune response, with the activation of macrophages involved in fungus phagocytosis. Immunization with live conidia produced a high influx of CD4 T cells into the draining lymph node. The sensitized T cells proliferate in vitro when restimulated with specific antigen and preferentially produce IFN- gamma. To better characterize the role played by T cells on the chromoblastomycosis infection we used mice deficient for CD4 and CD8. Data determined by CFU counts associated with decreased DTH and IFN-gamma production of infected mice clearly demonstrated that, during experimental F. pedrosoi infection, absence of CD4(+) cells induces a more severe disease.


Assuntos
Ascomicetos , Linfócitos T CD4-Positivos/imunologia , Cromoblastomicose/imunologia , Hipersensibilidade Tardia/imunologia , Animais , Bioensaio , Antígenos CD4/genética , Antígenos CD8/genética , Cromoblastomicose/genética , Hipersensibilidade Tardia/genética , Interferon gama , Depleção Linfocítica , Camundongos , Camundongos Mutantes
16.
Scand J Immunol ; 64(4): 382-7, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16970678

RESUMO

Chromoblastomycosis is characterized by the slow development of polymorphic skin lesions (nodules, verrucas, tumores, plaques and scar tissue). Inside the host, infectious propagules adhere to epithelial cells and differentiate into sclerotic forms, which effectively resist destruction by host effector cells and allow onset of chronic disease. A cellular immune response against fungi is essential to control infection. Amongst the cells of the immune system, macrophages play the most important role in controlling fungal growth. In this study, we show that the fungicidal characteristic of macrophages is dependent on the fungal species that causes chromoblastomycosis. We began by observing that the phagocytic index was higher for Fonsecaea pedrosoi and Rhinocladiella aquaspersa compared with that of other fungi. Complement-mediated phagocytosis was more important for Phialophora verrucosa and R. aquaspersa and was inhibited by mannan when F. pedrosoi and R. aquaspersa conidia were phagocytosed by macrophages. We showed that macrophages killed significantly only R. aquaspersa. We also found that the phagocytosis of fungi has functional consequences for macrophages as phagocytosis resulted in down-modulation of MHC-II and CD80 expression as well as in the inhibition of the basal liberation of NO. However, the inhibition of the basal liberation of NO nor the down-modulation of MHC and co-stimulatory molecules were observed in the presence of R. aquaspersa.


Assuntos
Ascomicetos/imunologia , Cromoblastomicose/imunologia , Cromoblastomicose/microbiologia , Citocinas/biossíntese , Mediadores da Inflamação/metabolismo , Macrófagos Peritoneais/microbiologia , Óxido Nítrico/biossíntese , Fagocitose/imunologia , Animais , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/isolamento & purificação , Células Cultivadas , Cromoblastomicose/metabolismo , Citocinas/fisiologia , Exophiala/crescimento & desenvolvimento , Exophiala/imunologia , Exophiala/isolamento & purificação , Feminino , Mediadores da Inflamação/fisiologia , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Phialophora/crescimento & desenvolvimento , Phialophora/imunologia , Phialophora/isolamento & purificação , Especificidade da Espécie , Virulência
17.
Scand J Immunol ; 62(4): 325-33, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16253119

RESUMO

Paracoccidioidomycosis (PCM) is caused by the dimorphic fungus Paracoccidioides brasiliensis. Immunostimulatory effects of P. brasiliensis DNA and CpG-oligodeoxyribonucleotides (CpG-ODN) have shown a Th2-Th1 immunomodulation of the isogenic murine model of susceptibility, which develops a progressive and disseminating disease. In this study, we investigated the optimum time interval and doses of CpG-ODN which are able to induce Th2-Th1 immunomodulation. The optimum concentrations for the induction of a decrease in antibody production were 0.5 and 1 microg. Mice immunized twice with CpG-ODN and gp43 (5 and 7 days before the challenge) showed a 60% higher chance of survival compared with the control group (nonimmunized), and an increase in Th1 isotype (IgG2a) was also observed. In vitro assays of naive and preimmunized mice showed discrete cellular proliferation when stimulated by suitable concentrations of CpG-ODN. Type 1 cytokines interleukin-12 (IL-12) and interferon-gamma were increased in cell culture supernatants, but no significant difference was found in Th2 IL-4 cytokines in stimulated or nonstimulated cell cultures. Concerning the Th2-Th1 kinetics in experimental PCM models by adjuvant effect of CpG-ODN, there are still many questions to be answered and clarified. However, the gathering of data obtained in this investigation has led us to suggest that the modulation of Th2-Th1 in experimental PCM depends on time and CpG-ODN concentration.


Assuntos
Adjuvantes Imunológicos/farmacologia , Antígenos de Fungos/genética , Proteínas Fúngicas/genética , Glicoproteínas/genética , Oligodesoxirribonucleotídeos/farmacologia , Paracoccidioides/genética , Paracoccidioidomicose/terapia , Células Th1/imunologia , Células Th2/imunologia , Animais , Anticorpos Antifúngicos/biossíntese , Anticorpos Antifúngicos/sangue , Proliferação de Células , Células Cultivadas , Citocinas/metabolismo , Relação Dose-Resposta Imunológica , Proteínas Fúngicas/síntese química , Genes Fúngicos/imunologia , Glicoproteínas/síntese química , Linfonodos/citologia , Linfonodos/imunologia , Linfonodos/metabolismo , Camundongos , Oligodesoxirribonucleotídeos/síntese química , Paracoccidioides/crescimento & desenvolvimento , Paracoccidioides/imunologia , Paracoccidioidomicose/imunologia , Paracoccidioidomicose/patologia , Baço/microbiologia , Baço/patologia , Células Th1/efeitos dos fármacos , Células Th2/efeitos dos fármacos
18.
Clin Exp Immunol ; 137(1): 123-8, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15196252

RESUMO

Paracoccidioidomycosis is a systemic mycosis endemic in Latin America, with a high prevalence in Brazil, Argentina, Colombia and Venezuela. The aetiological agent of disease is the thermal dimorphic fungus, Paracoccidioides brasiliensis. A glycoprotein of 43 kD (gp43) is the major antigen of P. brasiliensis. Antibodies directed to this antigen are detected in the sera of all patients with paracoccidioidomycosis (PCM). Recently, it has been shown that mice immunized with anti-gp43 monoclonal antibodies (MAbs) (Ab1), induce the idiotypic cascade in the gp43 system, which produced both, anti-Id antibodies (Ab2) and anti-anti-Id antibodies (Ab3). To further characterize the idiotypic cascade modulation in mice immunized with anti-gp43 MAb 17c, hybridomas were produced. Ab2 MAbs named 7.B12 inhibited (>95%) the binding of gp43 to MAb 17c (Ab1), suggesting that this anti-Id MAb bind to the idiotope, thus fulfilling the internal image criteria. To elucidate whether Ab2 MAb could act as antigen in serological assays, instead of gp43, sera from PCM patients were tested. Using an ELISA test, it was observed that antibodies from patients and not normal serum bound to Ab2. However, the ELISA test using Ab2 bound to the solid phase made possible to serologically monitor the patients after antifungal therapy, showing an equivalent curve when compared with ELISA test employing purified gp43. Our results also showed that, when mice were immunized with Ab2beta and their cells were exposed to gp43 in vitro, a T cell proliferation response was observed.


Assuntos
Anticorpos Anti-Idiotípicos/imunologia , Antígenos de Neoplasias/imunologia , Linfócitos B/imunologia , Paracoccidioides/imunologia , Paracoccidioidomicose/imunologia , Linfócitos T/imunologia , Animais , Anticorpos Monoclonais/imunologia , Antifúngicos/uso terapêutico , Divisão Celular/imunologia , Citocinas/biossíntese , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Paracoccidioidomicose/tratamento farmacológico
19.
Scand J Immunol ; 58(3): 290-7, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12950674

RESUMO

Paracoccidioidomycosis, endemic in Latin America, is a progressive systemic mycosis caused by Paracoccidioides brasiliensis. The infection can evolve into different clinical forms that are associated with various degrees of suppressed cell-mediated immunity. Assuming that the effector immune response is a consequence of the preferential activation of either Th1 or Th2 subsets, in the present work we evaluated whether the nature of antigen-presenting cells (APCs) can influence the Th1/Th2 balance in vivo. It was observed that the injection of mature dendritic cells (DCs), macrophages and B cells primed the mice and induced a proliferation of T cells in vitro. It was seen that DCs from resistant mice stimulated predominantly interleukin-2 (IL-2) and interferon-gamma (IFN-gamma), whereas macrophages activated IL-10, IL-4 and IFN-gamma-secreting T cells and B cells IL-4 and IL-10 only. Results presented here clearly demonstrate that DC drives the development of cells secreting Th1-derived cytokines, whereas B cells induce the differentiation of a Th2 phenotype in vivo.


Assuntos
Células Apresentadoras de Antígenos/imunologia , Antígenos de Fungos/imunologia , Proteínas Fúngicas/imunologia , Glicoproteínas/imunologia , Paracoccidioides/imunologia , Paracoccidioidomicose/imunologia , Células Th1/imunologia , Células Th2/imunologia , Animais , Apresentação de Antígeno/imunologia , Células Apresentadoras de Antígenos/citologia , Células Apresentadoras de Antígenos/metabolismo , Linfócitos B/citologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Diferenciação Celular/imunologia , Citocinas/biossíntese , Citocinas/imunologia , Células Dendríticas/citologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Ativação Linfocitária/imunologia , Macrófagos Peritoneais/citologia , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Camundongos , Camundongos Endogâmicos A , Células Th1/citologia , Células Th2/citologia
20.
Med Mycol ; 36(6): 405-11, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10206751

RESUMO

The yeast form of Paracoccidioides brasiliensis, the causative agent of a deep mycosis in humans, is known to be phagocytized by, and to multiply inside, macrophages. In this work we describe the involvement of gp43, a major antigenic protein of P. brasiliensis, in the initial steps of attachment of the fungus to macrophages. Anti-gp43 F(ab) polyclonal fragments were capable of inhibiting phagocytosis in a concentration-dependent manner. Sheep red blood cells sensitized with purified gp43 were more endocytized than SRBC alone, and this process was also inhibited by anti-gp43 F(ab) fragments. Inhibition tests indicated the involvement of fucose and mannose residues in the phagocytosis of the fungus and of SRBC-gp43 by macrophages. Taken together, these results suggest that gp43 may be involved in the adherence and uptake of the fungus by murine peritoneal macrophages, and that this binding may be dependent on monosaccharide residues that are part of the gp43 glycoprotein.


Assuntos
Antígenos de Fungos/fisiologia , Proteínas Fúngicas , Glicoproteínas/farmacologia , Macrófagos Peritoneais/microbiologia , Oligossacarídeos/farmacologia , Paracoccidioides/fisiologia , Animais , Anticorpos Antifúngicos , Anticorpos Monoclonais , Antígenos de Fungos/imunologia , Adesão Celular , Eritrócitos/imunologia , Glicoproteínas/imunologia , Glicoproteínas/isolamento & purificação , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Monossacarídeos/farmacologia , Oligossacarídeos/imunologia , Oligossacarídeos/isolamento & purificação , Paracoccidioides/imunologia , Fagocitose/efeitos dos fármacos , Ovinos
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