Vol 8, No 4 (2009)

Articles

  • XML | PDF | downloads: 291 | views: 427 | pages: 177-183

    FcεRI, The high affinity receptor for IgE plays a critical role in triggering the allergic reactions. It is responsible for inducing mast cell degranulation and deliberation of allergy mediators when it is aggregated by allergen and IgE complexes. FcεRI on the mast cells consists of three subunits; α chain directly binds IgE, β chain and dimmer of γ chains together mediate intracellular signaling. Cross-linking of IgE-bound FcεRI on the surface of mast cells and basophils by the multivalent antigen induces release of chemical mediators. The present in vitro study was designed to investigate the effect of synthetic FcεRI-α siRNA on the antigen-induced activation of MC/9 cells.
    MC/9 cells which are murine mast cells were transfected by FcεRI-α siRNA and negative control siRNA. After 6 h, anti-DNP (Dinitrophenyl) IgE was used for the cells sensitization. Then the cells were challenged with Dinitrophenyl-Human Serum Albumin (DNP-HSA) for mast cell degranulation induction before collection of supernatants. The amount of mRNA and protein expression was measured by Real Time PCR and western blot analysis, respectively. Determination of the expression rate of FcεRI-α on cell surface was achieved by flow cytometry. ELISA and spectrophotometry methods were used subsequently for measuring the effects of FcεRI-α siRNA on antigen-induced histamine and β-hexosaminidase release. FcεRI-α siRNA treated cells showed significant decrease in FcεRI-α mRNA and protein expression in comparison to control cells. FcεRI-mediated mast cell release of β-hexosaminidase and histamine were also inhibited.
    In this study it was shown that FcεRI-α siRNA could suppress FcεRI-α expression and inhibited degranulation and histamine release in antigen-stimulated MC/9 cells. In conclusion, knock-down of FcεRI-α by siRNA could be a promising method for inhibition of the mast cell-mediated allergic reactions.

  • XML | PDF | downloads: 277 | views: 463 | pages: 185-192

    A total of 65 pollen types were identified from two years atmospheric pollen survey in the environmental conditions of South Assam. Out of them, eight pollen types viz., Acacia auriculiformis, Amaranthus spinosus, Cassia alata, Cleome gynandra, Cocos nucifera, Imperata cylindrica, Ricinus communis and Trewia nudiflora, were selected for biochemical studies on the basis of their dominance in the study sites. Among the sample extract tested, Ricinus communis was found to contain the highest amount of soluble protein, free amino acid and total carbohydrate, per gram of dry weight followed by Imperata cylindrica and Cassia alata. Maximum numbers of protein polypeptide bands were detected in the sample extract of Cassia alata by polyacrylamide gel electrophoresis method followed by Acacia auriculiformis, Imperata cylindrica and Cocos nucifera. IgE binding protein fractions were maximum in Cassia alata and minimum in Trewia nudiflora.

  • XML | PDF | downloads: 251 | views: 332 | pages: 193-198

    It has been demonstrated that natural killer (NK) cells play a role in regulation of autoimmunity. They play a protective role in several rodent disease models. In this study we aimed to compare the immunophenotypic features of NK cells in Ankylosing Spondylitis (AS) with normal subjects with regard to CD56 and CD16 molecules.
    This study was carried out on 30 AS patients and 33 normal volunteer donors. Peripheral Blood Mononuclear cells (PBMC) were tested by flow cytometry detecting the intensity of CD56 and CD16 surface molecules. The percentage of positive cells and their subsets were then calculated and statistically analyzed using SPSS software. A significant increase was found in CD56+ CD16+ (P≤ 0.009), and also in the subset of CD56 dim CD16+ (P≤ 0.02), but not in CD56 bright CD16+ (P=0.3) NK cells in AS patients compared to controls. We conclude that these results may indicate that NK and their subset ratios play a role in AS pathogenesis. Moreover, determination of NK subsets in combination with clinical features may be useful for AS diagnosis. However, further studies using large samples together with determination of relevant cytokines are recommended to verify the exact role of NK in AS disease.

  • XML | PDF | downloads: 119 | views: 168 | pages: 199-203

    In this study, we evaluated the relationship between rhinosinusitis to the severity of asthma in asthmatic patients.
    This cross-sectional study was conducted on 90 patients with asthma referring to Imam Khomeini Hospital in Ardabil city. Asthma control stepping method was used for staging of asthma severity. Patients' clinical signs and paraclinical findings were individually evaluated and compared with particular attention to the presence or absence of rhinosinusitis. Chi square and t-test were used to analyze the data in SPSS15 software.
    Rhinosinusitis was found in 66 (73%) of the 90 patients. The Forced Expiratory Volume in 1 second (FEV1) was significantly lower in the patients who also had rhinosinusitis (P=0.002).Comparing severity of asthma, most of the patients with rhinosinusitis were in stage3 (42.4%) but most of the patients without rhinosinusitis were in stage1 (41.6%) (p=0.002).
    The results of this study confirm the correlation between asthma severity and rhinosinusitis in asthmatic patients. Therefore, in diagnosing asthma in patients, the possibility of the rhinosinusitis should be determined and treated.

  • XML | PDF | downloads: 253 | views: 390 | pages: 205-210

    Recent studies have proposed that a decline in bacterial infections such as tuberculosis is a factor underlying the rising prevalence and severity of atopic disorder in developed countries. There are conflicting ideas about the inverse relationship between BCG (Bacillus Calmette-Guerin) vaccination and asthma. Stronger response to tuberculin test as an indicator of more potent TH1 response is supposed to influence TH2 modulated allergic reactions. BCG scar considered as an indicator of TH1 - immunoresponse has been proposed to be smaller in asthmatic children in some studies.
    In a case-control study, 97 asthmatic and 97 control children younger than 5 years of age and BCG vaccinated at birth were tested with 5 units of tuberculin intradermaly. After 48-72 hours, the indurated area was measured in two diameters. Mean while, the scar of BCG in both groups was measured. Severity of asthma in the case group was recorded and categorized into mild, moderate and severe groups.
    The case group consisted of 63% boys and 37% girls and their tuberculin response was significantly smaller than that of the control (p=0.000), but no data supported the inverse relationship between the tuberculin response and severity of asthma (p=0.113). The scar of BCG was not significantly different in the asthmatic children with variable severity of asthma and control group (p=0.864).
    Children with definite asthma had a significant weaker response to tuberculin. This might be an indication of less potent TH1-reponse in allergic patients, but it was not associated with severity of asthma. No significant relationship between the size of BCG scar and asthma or its severity was found so perhaps BCG scar is not a sensitive indicator for development of asthma in future.

  • XML | PDF | downloads: 217 | views: 393 | pages: 211-214

    Atopic dermatitis (AD) is one of the most common infantile diseases. Immunological dysfunctions in AD patients may predispose them to infections. The aim of this study was to evaluate the relationship between infantile AD and urinary tract infection (UTI).
    In this cross sectional study, we enrolled 57 patients with AD aged 1 to 24 months that referred to dermatology clinic, and 57 healthy controls who were referred to pediatric clinic. The groups were matched according to age and gender.
    Urine samples were collected by clean-voided bag method. If a single organism was cultured at concentration of ≥105 organisms per millimeter and the existence of white blood cells more than 10 per microscopic field was seen the patients underwent suprapubic aspiration.
    The presence of one organism in suprapubic aspiration sample was regarded as positive culture. Data were analyzed using SPSS version 15 software. P value <0.05 was considered as the level of significance. Twelve (21.1%) of AD patients and 1(1.8%) of normal controls had positive urine culture tests. The difference between two groups was statistically significant (p = 0.001). The most common bacteria was E-coli.
    Infants with AD showed a higher frequency of UTI in this study. So, we suggest screening all AD infants for urinary tract infection.

  • XML | PDF | downloads: 142 | views: 224 | pages: 215-218

    Idiopathic CD4+ Lymphocytopenia is a rare combined immunodeficiency disease, characterized by low CD4+ T-cell count and increased susceptibility to opportunistic infections, autoimmunity and malignancies after exclusion of secondary forms of CD4 lymphocytopenia. Here we present a 13-year old boy who was referred to our center because of destructive ulceration of soft and hard palates with extension to nose and maxillary sinus starting at 6 months of age. He had a history of recurrent otitis media, chronic diarrhea, arthritis and herpetic lesions of eyes and mouth since the age of 5 years. Laboratory studies revealed very low number of CD4+ T-cells (<100 cells/mm3). Secondary causes of CD4 lymphocytopenia, including HIV infection, were ruled out. Immunohistological studies of destructive lesions in oral and nasal cavity revealed angiocentric T-cell lymphoma. Unfortunately, the patient died in spite of treatment with a combination of irradiation and chemotherapy. This patient is the first reported case of lethal midline granuloma with origin T-cell lymphoma in idiopathic CD4+ lymphocytopenia.

  • XML | PDF | downloads: 223 | views: 339 | pages: 219-220

    Hypersensitivity reactions to natural rubber latex have increased recently, especially among people with high exposure to latex allergens. Hypersensitivity reactions to latex are related to many conditions like occupational asthma. Our study was performed to determine the prevalence of hypersensitivity to natural rubber latex and potential food cross reactions in operation room personnel in Shiraz hospitals. In this cross-sectional, descriptive study, 580 operation room personnel filled out our questionnaire which included data about their personal history, symptoms of latex hypersensitivity, and other related allergies such as food hypersensitivity. An informed consent was obtained and skin prick tests were performed for natural rubber latex and potential food cross reactions (kiwi, banana, and potato). The obtained data were analyzed by SPSS and Chi-square test.
    Results: 104 (17.9%) of the operating room personnel showed positive latex skin tests. We revealed a significant correlation between those with positive skin tests to latex with atopia, urthicaria, and food hypersensitivity. The prevalence did not vary by sex, age, education, surgical and non-surgical gloves users, or history of contact dermatitis. Latex hypersensitivity is common among operation room personnel. Evaluation of symptoms and prediction of future diseases necessitate screening tests in individuals at risk.