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1.
Acta Med Okayama ; 76(3): 339-342, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35790366

RESUMO

A 90-year-old man presented with muscle weakness, difficulty concentrating, and dysphagia. About eighteen months prior to presentation, lansoprazole had been initiated to prevent stress ulcers; he also had a history of total thyroidectomy due to papillary thyroid cancer ten years prior. Laboratory findings were as follows: K 2.4 mEq/L, Ca 3.7 mg/dL, Mg 1.3 mg/dL, CK 5386 U/L, and intact PTH (iPTH) 14 pg/mL. Rhabdomyolysis with multiple electrolyte imbalances under proton pump inhibitor (PPI) treatment was diagnosed. We initiated intravenous hydration and electrolyte supplementation with discontinuation of PPI. After discontinuing PPI, the patient's serum magnesium, potassium, and calcium levels normalised with oral vitamin D and calcium supplementation. PPIs can cause hypocalcaemia and hypokalaemia via hypomagnesemia; hypocalcaemia is also a common postoperative complication of thyroidectomy. Careful monitoring of electrolyte levels is required in patients with long-term PPI treatment, especially in post-thyroidectomy cases.


Assuntos
Hipocalcemia , Rabdomiólise , Neoplasias da Glândula Tireoide , Idoso de 80 Anos ou mais , Cálcio , Humanos , Hipocalcemia/tratamento farmacológico , Hipocalcemia/etiologia , Masculino , Inibidores da Bomba de Prótons/uso terapêutico , Tireoidectomia/efeitos adversos
2.
J Intensive Care ; 12(1): 7, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360681

RESUMO

BACKGROUND: The HACOR score for predicting treatment failure includes vital signs and acid-base balance factors, whereas the ROX index only considers the respiratory rate, oxygen saturation, and fraction of inspired oxygen (FiO2). We aimed to externally validate the HACOR score and ROX index for predicting treatment failure in patients with coronavirus disease 2019 (COVID-19) on high-flow nasal cannula (HFNC) therapy in Japan. METHODS: This retrospective, observational, multicenter study included patients, aged ≥ 18 years, diagnosed with COVID-19 and treated with HFNC therapy between January 16, 2020, and March 31, 2022. The HACOR score and ROX index were calculated at 2, 6, 12, 24, and 48 h after stating HFNC therapy. The primary outcome was treatment failure (requirement for intubation or occurrence of death within 7 days). We calculated the area under the receiver operating characteristic curve (AUROC) and assessed the diagnostic performance of these indicators. The 2-h time-point prediction was considered the primary analysis and that of other time-points as the secondary analysis. We also assessed 2-h time-point sensitivity and specificity using previously reported cutoff values (HACOR score > 5, ROX index < 2.85). RESULTS: We analyzed 300 patients from 9 institutions (median age, 60 years; median SpO2/FiO2 ratio at the start of HFNC therapy, 121). Within 7 days of HFNC therapy, treatment failure occurred in 127 (42%) patients. The HACOR score and ROX index at the 2-h time-point exhibited AUROC discrimination values of 0.63 and 0.57 (P = 0.24), respectively. These values varied with temporal changes-0.58 and 0.62 at 6 h, 0.70 and 0.68 at 12 h, 0.68 and 0.69 at 24 h, and 0.75 and 0.75 at 48 h, respectively. The 2-h time-point sensitivity and specificity were 18% and 91% for the HACOR score, respectively, and 3% and 100% for the ROX index, respectively. Visual calibration assessment revealed well calibrated HACOR score, but not ROX index. CONCLUSIONS: In COVID-19 patients receiving HFNC therapy in Japan, the predictive performance of the HACOR score and ROX index at the 2-h time-point may be inadequate. Furthermore, clinicians should be mindful of time-point scores owing to the variation of the models' predictive performance with the time-point. Trial registration UMIN (registration number: UMIN000050024, January 13, 2023).

3.
PLoS One ; 17(6): e0270141, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35749694

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19) patients reportedly have high bicarbonate concentration. However, its relationship to the disease progression are obscure. METHODS: In this two-center retrospective study, we included COVID-19 patients with moderate severity between March 2020 and May 2021. We classified patients into three groups according to bicarbonate concentrations: high (>27 mEq/L), normal (21 to 27 mEq/L), and low (<21 mEq/L). The primary outcome was the time to clinical worsening defined by the requirement of intubation or death during 90 days. We evaluated high or low bicarbonate concentration during the clinical course related to the primary outcome using multivariable Cox proportional hazard models. RESULTS: Of the 60 participants (median age 72 years), 60% were men. Participants were classified into high (13 patients), normal (30 patients), and low (17 patients) groups. Clinical worsening occurred in 54% of patients in the high group, 23% in the normal group, and 65% in the low group. Both high and low groups were associated with a higher clinical worsening rate: HR, 3.02 (95% CI, 1.05 to 8.63) in the high group; 3.49 (95% CI: 1.33 to 9.12) in the low group. CONCLUSION: Monitoring of bicarbonate concentrations may be useful to predict the prognosis.


Assuntos
Bicarbonatos , COVID-19 , Idoso , Feminino , Humanos , Masculino , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos
4.
J Med Invest ; 68(3.4): 238-243, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34759137

RESUMO

Peripherally derived steroids affect steroid production in the brain via the blood-brain barrier. However, steroid concentrations are lower in the cerebrospinal fluid than those in the blood, indicating restricted influx of steroids because of their metabolization by choroid plexus (CP) epithelial cells. Here, we analyzed the gene expression of steroidogenic enzymes [cholesterol side-chain cleavage enzyme (P450scc), 17α-hydroxylase/C17-C20 lyase (P450c17), 3ß-hydroxysteroid dehydrogenase (3ß-HSD), 17ß-hydroxysteroid dehydrogenase type 1 (17ß-HSD1), aromatase (Cyp19a1), and 5α-reductase type 1 (5α-R1)]. These genes were expressed to a lesser extent in the CP than in the testis and to a similar extent in the cerebral cortex. However, P450scc levels were higher in the CP than in the cerebral cortex, whereas Cyp19a1 levels showed the opposite trend. We also evaluated the effects of orchiectomy and testosterone on the expression of these genes. P450c17 and 5α-R1 levels were unaffected by orchiectomy, whereas P450scc and 3ß-HSD levels were increased and decreased, respectively. Cyp19a1 expression increased upon testosterone treatment, whereas that of 17ß-HSD decreased upon orchiectomy or administration of testosterone. Immunohistochemistry analysis revealed that 17ß-HSD was expressed in the cytoplasm of CP epithelial cells. These results indicate that CP epithelial cells synthesize and convert the certain types of steroids to contribute to the homeostasis of steroids in the brain. J. Med. Invest. 68 : 238-243, August, 2021.


Assuntos
Enzima de Clivagem da Cadeia Lateral do Colesterol , Plexo Corióideo , Animais , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Plexo Corióideo/metabolismo , Masculino , Ratos , Esteroide 17-alfa-Hidroxilase/genética , Esteroide 17-alfa-Hidroxilase/metabolismo , Esteroides , Testosterona
5.
Parasitol Int ; 68(1): 40-47, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30189256

RESUMO

Toxoplasma gondii is a common perorally transmitted parasite; however, its immunopathogenesis in gut-associated tissues remains unclear. Here, we compared disease manifestation in C57BL/6 immunocompetent wild type (WT) mice and immunocompromised interferon (IFN)-γ-deficient (GKO) mice after peroral infection (PI) with T. gondii cysts (Fukaya strain). Strong PI-induced Th1 cytokine expression was detected in WT mice. Moreover, bradyzoite-specific T.g.HSP30/bag1 mRNA was detected in the ileum parenchyma and Peyer's patches (PP), but not in the mesenteric lymph nodes, at 7 days post-infection in WT mice, and was significantly higher than that in GKO mice. Nested PCR showed that parasites existed in ileum parenchyma at days 1 and 1.5 post-PI in GKO and WT mice, respectively. In addition, quantitative competitive-PCR indicated that T. gondii first colonized the PP (day 3 post-PI), followed by the ileum parenchyma and mesenteric lymph nodes, spleen, and portal and aortic blood (day 7 post-PI). Although parasites were consistently more abundant in GKO mice, similar invasion and dissemination patterns were observed in the two hosts. Collectively, these data suggest that some zoites differentiate from tachyzoites to bradyzoites in the ileum and that T. gondii initially invades the ileum parenchyma, and then accumulates and proliferates in the PP before disseminating through the lymphatic systems of both GKO and WT hosts.


Assuntos
Nódulos Linfáticos Agregados/parasitologia , Toxoplasma/imunologia , Toxoplasma/fisiologia , Toxoplasmose Animal/imunologia , Toxoplasmose Animal/parasitologia , Animais , Citocinas/imunologia , Íleo/parasitologia , Hospedeiro Imunocomprometido , Interferon gama/deficiência , Interferon gama/genética , Estágios do Ciclo de Vida/imunologia , Linfonodos/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nódulos Linfáticos Agregados/imunologia , Reação em Cadeia da Polimerase , Baço/parasitologia , Células Th1 , Toxoplasma/genética , Toxoplasma/isolamento & purificação
6.
Hepatol Res ; 38(10): 1040-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18513334

RESUMO

AIM: Non-parenchymal liver cells (NPLC) play an important role in the regulation of immune responses and the inflammatory process. In this study, we hypothesized that F4/80(+)Mac-1(high+) cells were involved in the regulative feedback-modulated regulation of inflammatory responses during concanavalin A (Con A)-induced hepatitis. METHODS: Hepatitis was induced in BALB/c mice by the intravenous injection of Con A. Liver injury was assessed using serum aminotransferase and pathology. The function of NPLC was assessed by FACS analysis. Accessory cell function of adherent Con A NPLC was performed with an ovalbumin specific T-helper 1 (Th1) clone proliferation assay. The culture supernatant nitric oxide (NO) content was quantified by the Griess reaction. Inducible NO synthase (iNOS) expression was demonstrated by immunohistochemistry and Western blot analysis. RESULTS: The number of hepatic F4/80(+)Mac-1(high+)cells increased in a time-dependent manner after Con A administration, which consequently suppressed Th1 cell proliferation by a mechanism likely to involve NO. The iNOS expression of NPLC was elevated at 24 h post-Con A injection. In nude mice, F4/80(+)Mac-1(high+)cells did not increase in the Con A-treated liver; the NPLC did not suppress Th1 clone proliferation. CONCLUSION: These findings suggest that the in vivo activation of F4/80(+)Mac-1(high+)cells by Con A administration suppresses Th1 cell proliferation by increasing NO, and subsequently reducing liver injury.

7.
Parasitol Int ; 57(4): 447-53, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18585475

RESUMO

Toxoplasma gondii infection was induced in wild type (WT) C57BL/6 and BALB/c mice and same-background interferon-gamma knockout (GKO) mice by peroral inoculation of Fukaya strain cysts. We studied parasitemia, absolute cell number of leukocytes, and cell susceptibility in peripheral blood leukocyte (PBL) subsets in vivo. Parasitemia was observed in both WT and GKO mice, although the pattern of the parasite load was totally different among them. After infection, the absolute number of neutrophils in peripheral blood increased in both GKO C57BL/6 and GKO BALB/c mice with statistical significance, while it rose up slightly in susceptible WT C57BL/6 mice, but declined moderately in resistant WT BALB/c mice. The absolute number of lymphocytes in both WT and GKO mice decreased significantly after infection. Although leukocyte number per mul decreased significantly in both strains of WT mice, it increased in GKO BALB/c mice. There were no differences in susceptibility of PBL subsets to T. gondii infection as assessed by quantitative competitive polymerase chain reaction in both WT and GKO mice. These results indicate that each of the PBL subsets was infected in vivo. The increase of neutrophils only among immunocompromised or susceptible strains suggests that the neutrophil may be involved in the lethal process of T. gondii infection. The lack of any difference in cell susceptibility per mug gDNA among the PBL subsets examined implies that the neutrophil may contribute to the whole body dissemination process of the parasite in vivo more than other PBL subsets through the increase in number.


Assuntos
Interferon gama/deficiência , Parasitemia/sangue , Toxoplasma/patogenicidade , Toxoplasmose Animal/sangue , Animais , Interferon gama/genética , Interferon gama/metabolismo , Contagem de Leucócitos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos/imunologia , Neutrófilos/parasitologia , Parasitemia/imunologia , Parasitemia/mortalidade , Parasitemia/parasitologia , Toxoplasma/imunologia , Toxoplasmose Animal/imunologia , Toxoplasmose Animal/mortalidade , Toxoplasmose Animal/parasitologia
8.
J Clin Neurosci ; 15(2): 158-65, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17981040

RESUMO

Anti-heat shock cognate protein 71 antibody (HSC71 Ab) formation in the sera of myasthenia gravis (MG) patients was measured, and the correlation between HSC71 Ab titers, clinical features and therapy efficacies for MG patients were examined. Clinical evaluations were performed according to the MG Foundation of America (MGFA) clinical classification. Therapy efficacies were measured using the MG activities of daily living (MG-ADL) score. Before treatment, 38 out of 48 serum samples (79%) from MG patients showed positive HSC71 Ab titers. In the "therapy-responsive group", HSC71 Ab titers significantly reduced, along with patient clinical improvements. Conversely, in the "therapy-resistant group", HSC71 Ab titers did not decline. The use of tacrolimus resulted in improvement in clinical manifestations together with a reduction in HSC71 Ab titers in the "therapy-resistant group". Thus, measurement of HSC71 Ab in the sera of MG patients seemed useful, as it appeared to reflect the effectiveness of treatment and allowed prediction of prognosis.


Assuntos
Autoanticorpos/sangue , Proteínas de Choque Térmico HSC70/imunologia , Miastenia Gravis/sangue , Atividades Cotidianas , Corticosteroides/uso terapêutico , Adulto , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/tratamento farmacológico , Miastenia Gravis/imunologia , Miastenia Gravis/psicologia , Receptores Colinérgicos/imunologia , Estatística como Assunto
9.
Parasitol Int ; 56(2): 141-8, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17307382

RESUMO

Toxoplasma gondii infection is generally asymptomatic in immunocompetent persons but can be life-threatening in immunocompromised persons and for fetuses in the case of maternal-fetal transmission. The effect of interferon (IFN)-gamma, which plays a crucial role in the protective immunity against T. gondii infection, on maternal-fetal transmission of T. gondii was analyzed by quantitative competitive polymerase chain reaction targeting T. gondii-specific SAG1 gene. T. gondii loads were obvious in uterus and placenta of wild type (WT) C57BL/6 (B6, susceptible strain) but not BALB/c (resistant strain) pregnant mice. Higher levels of T. gondii were detected in uterus and placenta of IFN-gamma knock-out (GKO) B6 and BALB/c than in those of WT mice. Furthermore, T. gondii was detected in fetus of GKO B6 but not GKO BALB/c, WT B6, or WT BALB/c mice. Thus, not only IFN-gamma but also genetic susceptibility to T. gondii infection was important for the protective immunity of maternal-fetal transmission of T. gondii to fetus via placenta. T. gondii-infected WT mice displayed a low delivery rate with high IFN-gamma production, whereas infected GKO mice did not. Additionally, mean body weight of neonates from T. gondii-infected GKO BALB/c pregnant mice was significantly lower than that of unaborted neonates from WT BALB/c pregnant mice, suggesting the effects of T. gondii infection on intrauterine growth retardation of fetus in pregnant GKO mice.


Assuntos
Complicações Infecciosas na Gravidez/imunologia , Toxoplasmose Animal/imunologia , Toxoplasmose Animal/transmissão , Animais , Feminino , Retardo do Crescimento Fetal/etiologia , Predisposição Genética para Doença , Transmissão Vertical de Doenças Infecciosas , Interferon gama/deficiência , Interferon gama/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Placenta/parasitologia , Doenças Placentárias/genética , Doenças Placentárias/parasitologia , Gravidez , Complicações Infecciosas na Gravidez/genética , Complicações Infecciosas na Gravidez/parasitologia , Toxoplasma , Toxoplasmose Animal/genética , Toxoplasmose Animal/parasitologia , Toxoplasmose Congênita/etiologia , Toxoplasmose Congênita/genética , Toxoplasmose Congênita/imunologia , Toxoplasmose Congênita/parasitologia
10.
Microbes Infect ; 8(4): 1045-53, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16515877

RESUMO

The ubiquitin-proteasome system (UPS) plays an indispensable role in inducing MHC class I-restricted CD8+ T cells and was exploited in the development of a DNA vaccine against the intracellular protozoan Toxoplasma gondii by constructing a chimeric DNA encoding a fusion protein between murine ubiquitin and the toxoplasma antigen SAG1. The SAG1 peptide was promptly degraded in antigen-presenting cells (APCs) transfected with the chimeric DNA. Degradation, however, was hampered by incubating the APCs with the proteasome inhibitor epoxomicin. Mice vaccinated with the DNA acquired potent protective immunity mediated by MHC class I-restricted CD8+ T cells against infection by the highly virulent Toxoplasma. The accelerated degradation and induction of immunity were dependent on the UPS since mice lacking an immuno-subunit of 20S proteasome, LMP7, lost these functions, although they were independent of the proteasome regulator PA28alpha/beta complex.


Assuntos
Antígenos de Protozoários/imunologia , Linfócitos T CD8-Positivos/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Complexo Principal de Histocompatibilidade/imunologia , Complexos Multienzimáticos/imunologia , Proteínas de Protozoários/imunologia , Vacinas Protozoárias/administração & dosagem , Toxoplasma/imunologia , Toxoplasmose/prevenção & controle , Ubiquitina/imunologia , Animais , Antígenos de Protozoários/metabolismo , Biolística , Feminino , Esquemas de Imunização , Complexo Principal de Histocompatibilidade/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Complexos Multienzimáticos/deficiência , Complexos Multienzimáticos/genética , Complexo de Endopeptidases do Proteassoma/imunologia , Proteínas/genética , Proteínas/imunologia , Proteínas de Protozoários/metabolismo , Proteínas Recombinantes de Fusão/administração & dosagem , Especificidade do Receptor de Antígeno de Linfócitos T , Toxoplasmose/imunologia , Ubiquitina/metabolismo , Vacinas de DNA/administração & dosagem
11.
Invest Ophthalmol Vis Sci ; 47(1): 265-71, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16384972

RESUMO

PURPOSE: To evaluate the effects of sulfamethoxazole (SMX) on experimental ocular toxoplasmosis by quantitative competitive polymerase chain reaction (QC-PCR) assay. METHODS: Wild-type (WT) C57BL/6 and WT BALB/c mice and interferon-gamma knockout (GKO) mice were infected orally with Toxoplasma gondii of the Fukaya strain. Mice were classified into groups. The first group (G1) remained untreated, the second group (G2) had a short SMX treatment period, and the third group (G3) received treatment continuously. WT and GKO mice were divided into G1 and G3, and G1, G2, and G3, respectively. T. gondii burdens were evaluated by QC-PCR assay. The effect on stage distribution was analyzed by reverse transcription-PCR. RESULTS: SMX significantly decreased mortality among the infected WT C57BL/6 and GKO mice. In WT G1 mice, T. gondii DNA was detected in all organs and tissues, although in G3 mice it was detected only in the brain. In GKO C57BL/6 G1 mice, the protozoan proliferated much more actively than in the WT mice. In the GKO C57BL/6 G2 mice, the number of T. gondii was less than in G1 during the treatment, although the protozoan reappeared after cessation of treatment. In GKO C57BL/6 G3 mice, T. gondii DNA was detected in the brain, optic nerve, and retina, but not in the iris, choroid, sclera, and blood. In GKO BALB/c mice, the patterns of the kinetics of protozoan abundance in various organs were similar or were milder than those in GKO C57BL/6 mice. In SMX-treated GKO mice, the percentage of bradyzoites increased and that of tachyzoites decreased in the organs and tissues. CONCLUSIONS: SMX decreased the parasitic load in both WT and GKO mice. SMX decreased the tachyzoite load but did not completely eliminate bradyzoites in GKO mice. The present mouse model was used successfully to assess treatment effects in a quantitative fashion.


Assuntos
Anti-Infecciosos/uso terapêutico , Coriorretinite/tratamento farmacológico , Interferon gama/deficiência , Sulfametoxazol/uso terapêutico , Toxoplasmose Animal/tratamento farmacológico , Toxoplasmose Ocular/tratamento farmacológico , Animais , Coriorretinite/genética , Coriorretinite/mortalidade , Coriorretinite/parasitologia , DNA de Protozoário/análise , Feminino , Interferon gama/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Parasitemia/tratamento farmacológico , Parasitemia/parasitologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Toxoplasma/efeitos dos fármacos , Toxoplasma/genética , Toxoplasmose Animal/genética , Toxoplasmose Animal/mortalidade , Toxoplasmose Animal/parasitologia , Toxoplasmose Ocular/genética , Toxoplasmose Ocular/mortalidade , Toxoplasmose Ocular/parasitologia
12.
Cell Stress Chaperones ; 11(1): 13-22, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16572725

RESUMO

Toxoplasma gondii-derived heat shock protein 70 (T.g.HSP70) induced maturation of bone marrow-derived dendritic cells (DCs) of wild-type (WT) C57BL/6 mice as evidenced by an increase in surface expression of MHC class I and II molecules and costimulatory molecules such as CD40, CD80, and CD86. Functionally, decreased phagocytic ability and increased alloreactive T cell stimulatory ability were observed in T.g.HSP70-stimulated DCs. These phenotypic and functional changes of T.g.HSP70-stimulated DCs were demonstrated in Toll-like receptor (TLR) 2- and myeloid differentiation factor 88 (MyD88)-deficient but not TLR4-deficient C57BL/6 mice. DCs from WT and TLR2-deficient but not TLR4-deficient mice produced IL-12 after T.g.HSP70 stimulation. T.g.HSP70-stimulated DCs from WT, TLR2-deficient, and MyD88-deficient, but not TLR4-deficient mice expressed IFN-beta mRNA. Thus, T.g.HSP70 stimulates murine DC maturation via TLR4 through the MyD88-independent signal transduction cascade.


Assuntos
Células da Medula Óssea/citologia , Células Dendríticas/fisiologia , Proteínas de Choque Térmico HSP70/imunologia , Receptor 4 Toll-Like/imunologia , Toxoplasma/imunologia , Animais , Feminino , Proteínas de Choque Térmico HSP70/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Toxoplasma/metabolismo
13.
Parasitol Int ; 65(1): 1-4, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26384856

RESUMO

The abundance of Toxoplasma gondii with or without sulfamethoxazole (SMX) treatment was evaluated with quantitative competitive polymerase chain reaction in various organs of wild-type C57BL/6 mice, a susceptible immunocompetent host, after peroral infection with a cyst-forming Fukaya strain of T. gondii. SMX affected different organs in three ways: T. gondii was reduced independently of SMX (skin and kidney); T. gondii was not eradicated with continuous treatment (brain, heart, and lung); and T. gondii was eradicated with continuous treatment (tongue, skeletal muscle, and small intestine). The SMX concentrations in the brains, hearts, and lungs were higher in infected mice than in uninfected mice. These results indicate that even in an immunocompetent host, chemotherapy is necessary to reduce the parasite load and thus reduce the risk of recurrent disease.


Assuntos
Coccidiostáticos/uso terapêutico , Imunocompetência , Sulfametoxazol/uso terapêutico , Toxoplasma/efeitos dos fármacos , Toxoplasmose Animal/tratamento farmacológico , Toxoplasmose Animal/parasitologia , Animais , Encéfalo/metabolismo , Encéfalo/parasitologia , Coccidiostáticos/farmacocinética , Coccidiostáticos/farmacologia , DNA de Protozoário , Modelos Animais de Doenças , Coração/parasitologia , Pulmão/metabolismo , Pulmão/parasitologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Carga Parasitária , Reação em Cadeia da Polimerase em Tempo Real , Sulfametoxazol/farmacocinética , Sulfametoxazol/farmacologia , Toxoplasma/genética , Toxoplasma/crescimento & desenvolvimento
14.
Invest Ophthalmol Vis Sci ; 46(1): 317-21, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15623791

RESUMO

PURPOSE: To investigate by ERG the effects of Toxoplasma gondii infection on the visual function of interferon gamma knockout (GKO) mice, as a model of immunocompromised hosts. METHODS: Susceptible wild-type (WT) C57BL/6 and GKO C57BL/6 mice were infected with five cysts of the avirulent T. gondii perorally. ERGs were recorded before and after the infection. The eyes of WT and GKO mice were enucleated and prepared for histologic studies 4 weeks and 12 days after infection, respectively. RESULTS: The a- and b-waves of ERGs did not change significantly up to 1 month after infection in WT mice, but those of GKO mice were significantly reduced 11 days after infection. Histopathology revealed focal retinitis and vasculitis in WT mice 4 weeks after infection. Mild inflammation and sludging of blood in the retina and choroid were found in GKO mice 12 days after infection, just before death. Cysts were found in the inner nuclear layer, with little disturbance of the surrounding retinal architecture in both WT and GKO mice. CONCLUSIONS: ERG clearly showed deterioration of visual function in GKO but not in WT mice after T. gondii infection. ERG is a sensitive and reliable method for observing activity in mice severely affected with experimental toxoplasmic retinochoroiditis.


Assuntos
Coriorretinite/fisiopatologia , Eletrorretinografia/métodos , Interferon gama/fisiologia , Retina/fisiopatologia , Toxoplasmose Animal/fisiopatologia , Toxoplasmose Ocular/fisiopatologia , Acuidade Visual/fisiologia , Animais , Feminino , Interferon gama/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Rinsho Shinkeigaku ; 45(2): 105-10, 2005 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-15782608

RESUMO

We report a 44-year-old woman with toxoplasma encephalitis that occurred during cyclosporine monotherapy for Behçet disease. She had been treated with cyclosporine for 8 years. She experienced headache and, nausea, and then consciousness disturbance developed. Brain MRI showed high-signal intensity lesions on T1-weighted MRI with Gd-enhancement in the left temporoparietal lobe, right thalamus and right frontal and temporal lobes. The pathological examination of the biopsied brain specimens suggested toxoplasma encephalitis. She improved rapidly after the administration of antibiotics for toxoplasma gondii. Anti-toxoplasma specific protein antibodies were positive in the serum and CSF, supporting a diagnosis of acute toxoplasmosis. Toxoplasma encephalitis due to cyclosporine mono-therapy has not been reported yet. The measurement of anti-toxoplasma specific protein antibodies may be useful for the early, accurate diagnosis of toxoplasmosis.


Assuntos
Síndrome de Behçet/tratamento farmacológico , Ciclosporina/efeitos adversos , Encefalite/etiologia , Toxoplasmose Cerebral/etiologia , Adulto , Feminino , Humanos , Infecções Oportunistas/etiologia
16.
Invest Ophthalmol Vis Sci ; 44(10): 4375-81, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14507882

RESUMO

PURPOSE: To establish a mouse model of ocular toxoplasmosis in both wild type (WT) and immunocompromised hosts and to clarify the effects of interferon (IFN)-gamma on the infectivity of Toxoplasma gondii in various parts of the eye. METHODS: Susceptible WT C57BL/6, resistant WT BALB/c, and IFN-gamma knockout (GKO) mice were infected with cysts of T. gondii perorally. The tissues were harvested for molecular and histopathologic studies. Analysis included a quantitative competitive polymerase chain reaction (QC-PCR) assay and reverse transcription (RT)-PCR for IFN-gamma and stage conversion markers. All animals underwent ophthalmic examinations including fluorescein angiography (FA). RESULTS: In WT C57BL/6 mice, T. gondii was detected in tissue in the following order: brain, retina, choroid, sclera, and optic nerve (ON). The highest T. gondii load was observed in the posterior retina, and was much greater than that in WT BALB/c mice. In GKO mice, disseminated infection was evident, and the T. gondii load was highest in the choroid and ON. IFN-gamma mRNA expression in WT C57BL/6 mice was higher than that in WT BALB/c mice after infection. Tachyzoites existed in GKO mice, whereas bradyzoites existed in WT C57BL/6 mice. FA showed dye leakage from the retinal capillaries of GKO mice. CONCLUSIONS: The T. gondii load in the retina in the susceptible WT strain continued to increase, unlike in the resistant WT strain. IFN-gamma was shown to regulate the T. gondii load and interconversion in the eye. A toxoplasmic vasculitis model was established with GKO mice and assay systems with QC-PCR and FA.


Assuntos
Olho/parasitologia , Interferon gama/fisiologia , Vasculite Retiniana/parasitologia , Toxoplasma/isolamento & purificação , Toxoplasmose Ocular/parasitologia , Animais , Antígenos de Protozoários/genética , Antígenos de Protozoários/metabolismo , Encéfalo/metabolismo , Encéfalo/parasitologia , Encéfalo/patologia , Modelos Animais de Doenças , Olho/metabolismo , Olho/patologia , Angiofluoresceinografia , Proteínas de Choque Térmico HSP30 , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Hospedeiro Imunocomprometido , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , RNA Mensageiro/metabolismo , Vasculite Retiniana/metabolismo , Vasculite Retiniana/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Distribuição Tecidual , Toxoplasmose Ocular/metabolismo , Toxoplasmose Ocular/patologia
17.
Int Rev Immunol ; 21(4-5): 405-21, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12486821

RESUMO

IFN-gamma downregulates the stage conversion of Toxoplasma gondii (T. gondii), from bradyzoites to tachyzoites, and the expression of heat shock protein 70 (HSP70) of T. gondii (T.g.HSP70) by tachyzoites. T.g.HSP70 has been shown to downregulate NO release from macrophages and also to induce auto-HSP70 antibody formation and IL-10 secretion by VH11-JH1 B-1 cells, resulting in the suppression of host defense responses to T. gondii infection. A novel category of virulent tachyzoite stage of T. gondii expressing T.g.HSP70 (virulent tachyzoite), which indirectly manifests its pathogenicity by downregulating host defense responses, has been proposed.


Assuntos
Interferon gama/fisiologia , Toxoplasma/fisiologia , Animais , Camundongos
18.
Cell Stress Chaperones ; 7(4): 357-64, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12653480

RESUMO

We have investigated the role of Toxoplasma gondii-derived heat shock protein 70 (TgHSP70) as a B cell mitogen by measuring proliferative responses in vitro. TgHSP70 induced prominent proliferative responses in murine B cells derived not only from T gondii-infected but also from uninfected mice. Nude mice responded to TgHSP70; however, severe combined immunodeficiency, RAG1-/- B6, and microMT mice failed to respond. B220+ spleen cells showed marked proliferation after stimulation with TgHSP70, but neither CD4+ nor CD8+ population responded. This unresponsiveness of CD4+ and CD8- T cells to TgHSP70 was antigen presenting cells independent. These data indicate that TgHSP70 induced the proliferation of B cells but not T cells. Polymyxin B, a potent inhibitor of lipopolysaccharide (LPS), did not eliminate TgHSP70-induced proliferation. C3H/HeN mice responded well to TgHSP70 stimulation; however, C3H/HeJ mice carrying a point mutation in the Toll-like receptor (TLR) 4 failed to respond. This indicates that TLR4 is required for TgHSP70-induced B cell activation. The involvement of TLR4 in the TgHSP70-induced proliferative responses of spleen cells was also shown by the use of TLR4-/- mice. But TgHSP70-induced, but not LPS-induced, spleen cell proliferation was observed in MyD88-/- mice, indicating that the MyD88 molecule was involved in LPS-induced proliferation but not in TgHSP70-induced proliferation.


Assuntos
Linfócitos B/imunologia , Divisão Celular/imunologia , Proteínas de Choque Térmico HSP70/imunologia , Mitógenos/imunologia , Toxoplasma/imunologia , Toxoplasmose/imunologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Antígenos de Diferenciação/genética , Linfócitos B/efeitos dos fármacos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Proteínas de Choque Térmico HSP70/farmacologia , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/imunologia , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/metabolismo , Masculino , Glicoproteínas de Membrana/deficiência , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Knockout , Camundongos SCID , Mitógenos/farmacologia , Dados de Sequência Molecular , Fator 88 de Diferenciação Mieloide , Polimixina B/farmacologia , Receptores de Superfície Celular/deficiência , Receptores de Superfície Celular/genética , Receptores Imunológicos/deficiência , Receptores Imunológicos/genética , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Receptor 4 Toll-Like , Receptores Toll-Like , Toxoplasma/metabolismo , Toxoplasmose/metabolismo
19.
Int Immunopharmacol ; 4(7): 911-20, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15182730

RESUMO

Phospholipase C (PLC)gamma and phospholipase D (PLD) play pivotal roles in the signal transduction required for various cellular responses, including cell proliferation and differentiation. Dendritic cells (DCs), which are professional antigen-presenting cells, can be generated from human monocytes by stimulating the cells with granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin 4 (IL-4). We investigated whether PLCgamma and PLD expression levels can be changed during the differentiation of the human monocytes into DCs. The enzymatic activity and protein level of PLC gamma1 were significantly increased in the human monocyte-derived DCs by GM-CSF/IL-4, but the protein levels of PLC gamma2 were unaltered. Moreover, the enzymatic activity and protein level of PLD1b and PLD2 were up-regulated during the differentiation of human monocytes to DCs, but those of PLD1a were not changed. A higher phagocytic activity of DCs was found to be correlated with the up-regulations of PLCgamma1 and PLD, and the phagocytic activity of DCs was inhibited by a PLC-specific inhibitor (U73122) and by a phosphatidic acid acceptor (n-butanol), but to be increased by phosphatidic acid. Thus, suggesting that PLC and PLD participate in the process. This study suggests that the up-regulations of PLCgamma1 and PLD are accompanied by the differentiation of monocytes into DCs, which results in increased phagocytic activity.


Assuntos
Células Dendríticas/efeitos dos fármacos , Monócitos/efeitos dos fármacos , Fosfolipase D/biossíntese , Fosfolipases Tipo C/biossíntese , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Células Dendríticas/enzimologia , Glicerofosfolipídeos/biossíntese , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Interleucina-4/farmacologia , Monócitos/citologia , Monócitos/enzimologia , Fagocitose/efeitos dos fármacos , Fosfolipase C gama , Fosfolipase D/imunologia , Transdução de Sinais , Fosfolipases Tipo C/imunologia , Regulação para Cima
20.
Parasitol Int ; 51(2): 187-94, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12113757

RESUMO

In a theoretical analysis of the present study, we quantitatively indicate a potential threat of congenital toxoplasmosis to Japanese young women by the use of a simple mathematical model or a special case of the well-known catalytic infection model. For introducing a risk function of congenital toxoplasmosis, an annual infection rate, r, was divided into r(1), the rate before age a(0 < a < 15), and r(2), the rate after age a. Presuming the values of r(1), r(2) and a on the basis of the current situation of Toxoplasma infection in Japan, simulation analyses were performed with the mathematical model. As the simulation clearly demonstrated, Japanese young women are potentially facing a threat of congenital toxoplasmosis, although the current risk of it is relatively lower. From the viewpoint of risk management, public intervention programs are required. Based on our analyses, public intervention programs can be classified into two groups: group 1 for women before age a and group 2 for those after age a, and each group is expected to give a different kind of effect to the risk of congenital toxoplasmosis. The present study implies that a certain public intervention program could augment the risk, inadvertently.


Assuntos
Programas de Rastreamento , Modelos Biológicos , Cuidado Pré-Natal , Toxoplasma/imunologia , Toxoplasmose Congênita/epidemiologia , Toxoplasmose Congênita/prevenção & controle , Adolescente , Adulto , Animais , Anticorpos Antiprotozoários/sangue , Feminino , Educação em Saúde , Humanos , Recém-Nascido , Japão/epidemiologia , Pessoa de Meia-Idade , Gravidez , Complicações Parasitárias na Gravidez , Risco , Fatores de Risco , Testes Sorológicos , Toxoplasmose Congênita/diagnóstico
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