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1.
Artigo em Inglês | MEDLINE | ID: mdl-31421663

RESUMO

BACKGROUND: A skin prick test (SPT) and food challenge test (OFC) are useful in identification of food sensitization and food allergy. OBJECTIVE: To evaluate food allergen sensitization by SPT and food allergy by OFC in allergic Thai patients METHODS: SPTs for common food allergens were performed on allergic patients at Siriraj Hospital, Bangkok, Thailand, from 2011 to 2015. An OFC was performed in positive food SPT patients with informed consent. RESULTS: SPTs to food were positive in 539 (20%) out of 2,678 allergic patients (73.8% were < 10 years old). Crab was the most common sensitized food in each year of the study period. In patients aged < 1 year, the most common sensitized foods were egg white (23.8%) and wheat (22.2%), while shrimp was for patients aged > 10 years (25%). A positive OFC was found in 29 (26.1%) out of the 111 OFCs performed (9.1% in patients with asthma, 28.6% in allergic rhinitis and 26.3% in food allergy). Positive OFCs were found for 60% of the crab, 35.7% of the egg yolk, and 31% of the cow's milk OFCs. Compared to OFC, SPT showed high specificity (71%-100%) but low sensitivity (0%-40%). The percentage of sensitization to egg white, egg yolk, wheat, soy, and peanut significantly increased (p < 0.05) from 2011 to 2015. CONCLUSION: The sensitization to egg white, egg yolk, wheat, soy, and peanut significantly increased and crab was the most common sensitized food. Food allergy in patients with allergic rhinitis was as common as in patients diagnosed food allergy.

2.
Front Immunol ; 9: 1710, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30090103

RESUMO

A vaccine against schistosomiasis would contribute to a long-lasting decrease in disease spectrum and transmission. Our previous protection studies in mice using Schistosoma mansoni Cathepsin B (Sm-Cathepsin B) resulted in 59 and 60% worm burden reduction with CpG oligodeoxynucleotides and Montanide ISA720 VG as adjuvants, respectively. While both formulations resulted in significant protection in a mouse model of schistosomiasis, the elicited immune responses differed. Therefore, in this study, we aimed to decipher the mechanisms involved in Sm-Cathepsin B vaccine-mediated protection. We performed in vitro killing assays using schistosomula stage parasites as targets for lung-derived leukocytes and serum obtained from mice immunized with Sm-Cathepsin B adjuvanted with either Montanide ISA 720 VG or CpG and from non-vaccinated controls. Lung cells and immune sera from the Sm-Cathepsin B + Montanide group induced the highest killing (63%) suggesting the importance of antibodies in cell-mediated parasite killing. By contrast, incubation with lung cells from Sm-Cathepsin B + CpG immunized animals induced significant parasite killing (53%) independent of the addition of immune serum. Significant parasite killing was also observed in the animals immunized with Sm-Cathepsin B alone (41%). For the Sm-Cathepsin B + Montanide group, the high level killing effect was lost after the depletion of CD4+ T cells or natural killer (NK) cells from the lung cell preparation. For the Sm-Cathepsin B + CpG group, high parasite killing was lost after CD8+ T cell depletion, and a reduction to 39% was observed upon depletion of NK cells. Finally, the parasite killing in the Sm-Cathepsin B alone group was lost after the depletion of CD4+ T cells. Our results demonstrate how the different Sm-Cathepsin B formulations influence the immune mechanisms involved in parasite killing and protection against schistosomiasis.

3.
Asian Pac J Allergy Immunol ; 36(2): 69-76, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29161054

RESUMO

BACKGROUND: Flooding may affect aeroallergen sensitization. OBJECTIVE: To evaluate aeroallergen sensitization in children with asthma and/or allergic rhinitis (AR) by skin prick test (SPT) before and after the great flood of 2011 in Bangkok, Thailand. METHODS: The study was performed retrospectively in asthma and/or AR children (aged 0-18 years) in Siriraj Hospital, Bangkok, Thailand from 2009 to 2013. All of the cases received SPT with common aeroallergens. RESULTS: SPTs were performed from 2009-2013 in a total of 2,010 asthma and/or AR children and 58.2% and 60.5% showed positive results, respectively. Poly-sensitization to aeroallergens was found in 67.5% of asthma and 67.0% of AR SPT-positive patients. In the study period, Dermatophagoides pteronyssinus (Dp) and Dermatophagoides ferinae (Df) were the most common causes of aeroallergen sensitization (82.4% and 76.5%, respectively), followed by American cockroach (43.5%). After the severe flood in Bangkok in 2011, the trend of sensitization to American cockroach, Bermuda grass, Johnson grass, and Cladosporium spp. significantly decreased. However, the trend of sensitization to dog and Alterneria allergens in 2010 studied cases, significantly increased. During the study period, mean wheal diameter (MWD) of dog SPT was significantly associated with asthma severity, while the MWD of Dp SPT was significantly associated with AR severity. CONCLUSIONS: The aeroallergen sensitizations patterns had changed from previous years compared to the year during or after the flood. Thus, the great flood may have had a major impact on types of sensitization and the clinical patterns of airway allergy. Further confirmed by a prospective study is warranted.


Assuntos
Poluentes Atmosféricos/imunologia , Alérgenos/imunologia , Asma/epidemiologia , Inundações , Rinite Alérgica/epidemiologia , Adolescente , Asma/etiologia , Asma/imunologia , Criança , Pré-Escolar , Desastres , Feminino , Humanos , Lactente , Masculino , Prevalência , Estudos Retrospectivos , Rinite Alérgica/etiologia , Rinite Alérgica/imunologia , Tailândia/epidemiologia
4.
Sci Transl Med ; 9(420)2017 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-29237759

RESUMO

An effective Zika virus (ZIKV) vaccine will require long-term durable protection. Several ZIKV vaccine candidates have demonstrated protective efficacy in nonhuman primates, but these studies have typically involved ZIKV challenge shortly after vaccination at peak immunity. We show that a single immunization with an adenovirus vector-based vaccine, as well as two immunizations with a purified inactivated virus vaccine, afforded robust protection against ZIKV challenge in rhesus monkeys at 1 year after vaccination. In contrast, two immunizations with an optimized DNA vaccine, which provided complete protection at peak immunity, resulted in reduced protective efficacy at 1 year that was associated with declining neutralizing antibody titers to subprotective levels. These data define a microneutralization log titer of 2.0 to 2.1 as the threshold required for durable protection against ZIKV challenge in this model. Moreover, our findings demonstrate that protection against ZIKV challenge in rhesus monkeys is possible for at least 1 year with a single-shot vaccine.


Assuntos
Vacinas Virais/imunologia , Infecção por Zika virus/imunologia , Infecção por Zika virus/virologia , Zika virus/imunologia , Animais , Antígenos Virais/imunologia , DNA Viral/metabolismo , Feminino , Macaca mulatta , Camundongos Endogâmicos BALB C , Vacinação
5.
Pediatr Emerg Care ; 2017 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-28614101

RESUMO

OBJECTIVE: The purpose of this study was to evaluate the clinical characteristics of allergy to stings from the Hymenoptera order of insects in a hospital in Thailand. METHODS: A descriptive retrospective analytical study was carried out in inpatients and outpatients suffering from Hymenoptera stings from 2009 to 2013 in Siriraj Hospital. RESULTS: Medical records of 386 patients with an allergy to Hymenoptera stings were evaluated. Anaphylaxis was more common in patients younger than 15 years, who comprised 22.3% of patients in this study. The most common sting type was from wasps (58.3%). Eighty-five percent of patients sought medical treatment less than 24 hours after being stung. A systemic reaction and anaphylaxis were found in 9.9% and 4.4% of subjects, respectively. In 17 patients with anaphylaxis, only 11 patients (64.7%) received an epinephrine (adrenaline) injection as treatment, and only 8 (47.1%) received epinephrine autoinjectors or epinephrine-prefilled syringes to prevent a possible subsequent severe reaction. Significantly more patients younger than 15 years received epinephrine for prevention of an allergic reaction than did those older than 15 years (87.5% vs 11.7%, P < 0.001). Antibiotics were given to 43.0% of patients. CONCLUSIONS: Anaphylaxis from Hymenoptera stings was more common in children than in adults. Only half of the patients visited the emergency room within 1 hour of being stung. Overuse of antibiotics and underuse of epinephrine were found. More information about Hymenoptera stings should be provided to the public, and the use of epinephrine should be encouraged in the case of severe reactions and anaphylaxis.

6.
Asian Pac J Allergy Immunol ; 34(4): 295-299, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27362402

RESUMO

BACKGROUND: The skin prick test (SPT) is a valid and approved tool that is used to diagnose atopic diseases. The SPT is accurate, safe, simple and inexpensive. However, the histamine concentration used as a positive control in the SPT varies among centers. OBJECTIVE: To compare SPT results using different concentrations of locally-prepared and imported histamine solutions. METHOD: This prospective, randomized, double-blind, self-controlled study was performed in healthy adult volunteers. The SPT was performed using 4 concentrations of histamine solutions (imported, 1 mg/mL; locally-prepared, 1, 5 and 10 mg/mL). Locally-prepared histamine positive controls were prepared from histamine biphosphate monohydrate using sterile technique. RESULTS: Seventy-five adult volunteers (mean age, 36 years) were included in the study. Eight volunteers were male and 9 had a history of atopy. Mean wheal diameter (MWD) for imported histamine was 3.49 mm for a concentration of 1 mg/mL, and that of locally-prepared histamine was 2.94 mm, 5.05 mm and 5.52 mm for concentrations of 1, 5 and 10 mg/mL histamine, respectively. Negative SPT results (MWD <3 mm) were found in 11 subjects (14.7%) who received imported histamine and 26 subjects (34.7%) who received the locally-prepared histamine at concentration of 1 mg/mL. All subjects tested with locally-prepared histamine at concentrations of 5 and 10 mg/mL had a MWD > 3 mm. CONCLUSIONS: Locally-prepared histamine base at concentrations of 5 and 10 mg/mL yielded better positive results than both imported and locally-prepared histamine at a concentration of 1 mg/mL.


Assuntos
Agonistas dos Receptores Histamínicos/administração & dosagem , Histamina/análogos & derivados , Hipersensibilidade Imediata/diagnóstico , Testes Cutâneos/métodos , Adulto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Histamina/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
7.
BMC Infect Dis ; 16: 112, 2016 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-26945988

RESUMO

BACKGROUND: Schistosomiasis is the most important human helminth infection due to its impact on public health. The clinical manifestations are chronic and significantly decrease an individual's quality of life. Infected individuals suffer from long-term organ pathologies including fibrosis which eventually leads to organ failure. The development of a vaccine against this parasitic disease would contribute to a long-lasting decrease in disease spectrum and transmission. METHOD: Our group has chosen Schistosoma mansoni (Sm) cathepsin B, a peptidase involved in parasite feeding, as a prospective vaccine candidate. Our experimental formulation consisted of recombinant Sm-cathepsin B formulated in Montanide ISA 720 VG, a squalene based adjuvant containing a mannide mono-oleate emulsifier. Parasitological burden was assessed by determining adult worm, hepatic egg, and intestinal egg numbers in each mouse. Serum was used in ELISAs to evaluate production of antigen-specific antibodies, and isolated splenocytes were stimulated with the antigen for the analysis of cytokine secretion levels. RESULTS: The Sm-cathepsin B and Montanide formulation conferred protection against a challenge infection by significantly reducing all forms of parasitological burdens. Worm burden, hepatic egg burden and intestinal egg burden were decreased by 60%, 6%, and 56%, respectively in immunized animals compared to controls (P = 0.0002, P < 0.0001, P = 0.0009, respectively). Immunizations with the vaccine elicited robust production of Sm-cathepsin B specific antibodies (endpoint titers = 122,880). Both antigen-specific IgG1 and IgG2c titers were observed, with the former having more elevated titers. Furthermore, splenocytes isolated from the immunized animals, compared to control animals, secreted higher levels of key Th1 cytokines, IFN-γ, IL-12, and TNF-α, as well as the Th2 cytokines IL-5 and IL-4 when stimulated with recombinant Sm-cathepsin B. The Th17 cytokine IL-17, the chemokine CCL5, and the growth factor GM-CSF were also significantly increased in the immunized animals compared to the controls. CONCLUSION: The formulation tested in this study was able to significantly reduce all forms of parasite burden, stimulate robust production of antigen-specific antibodies, and induce a mixed Th1/Th2 response. These results highlight the potential of Sm-cathepsin B/Montanide ISA 720 VG as a vaccine candidate against schistosomiasis.


Assuntos
Catepsina B , Proteínas de Helminto , Schistosoma mansoni , Esquistossomose mansoni , Vacinas , Animais , Catepsina B/química , Catepsina B/imunologia , Proteínas de Helminto/química , Proteínas de Helminto/imunologia , Camundongos , Schistosoma mansoni/química , Schistosoma mansoni/imunologia , Esquistossomose mansoni/imunologia , Esquistossomose mansoni/parasitologia , Esquistossomose mansoni/prevenção & controle
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