Parietaria
Double-blind, placebo-controlled study of immunotherapy with Parietaria judaica: clinical efficacy and tolerance. (1/6)
Allergy to Parietaria causes significant morbidity in most Mediterranean areas. The aim of this study is to investigate the efficacy and tolerance of Parietaria depot extract at 25 BU/mL (1.5 microg/mL Par j 1). We performed a multicenter double-blind, placebo-controlled study in rhinitic patients with/without asthma, sensitized to Parietaria. 42 patients followed 20-month immunotherapy. Clinical efficacy was based on symptom and medication scores and the percentage of healthy days (days without symptoms or medication). Severity of asthma/rhinitis scales, visual analogue scale, evaluation of the treatment by doctors and patients, immediate and delayed cutaneous response and quality of life questionnaires were also studied. The active group showed a sustained decrease in symptoms (p = 0.008), medication (p = 0.009) and both (p = 0.001), and an increase in healthy days (p = 0.001) throughout the study, with a threefold increase of healthy days and almost a three time reduction in medication only after one year of treatment. Asthma and rhinitis severity scales also decreased after immunotherapy, and blinded clinical evaluation by physicians confirmed efficacy in 85% and 77% of the active patients. Patient's self-evaluation returned similar results. None of these changes were observed with placebo. Immediate cutaneous response was significantly reduced at the maintenance phase in the active group and remained reduced throughout the study. Late-phase response after intradermal testing also showed a statistical decrease in actively treated patients. Immunotherapy was well tolerated and every systemic reaction reported was mild. In conclusion, immunotherapy with Parietaria 25 BU/mL is an effective and safe treatment for patients with respiratory allergies. (+info)Age, gender and reactivity to allergens independently influence skin reactivity to histamine. (2/6)
BACKGROUND: The ability to mount an IgE response to allergens is a prerequisite for the development of positive allergen skin tests. Histamine is commonly used as a positive control in skin prick testing and provides a measure of nonspecific skin reactivity, similar to bronchial hyper-responsiveness. METHODS: To determine whether allergen responsiveness, age, gender and season of the year contribute to histamine sensitivity, 620 subjects (502 of them with at least one known sensitizing allergen and the remaining 118 non-allergic controls) were prick-tested with a panel of allergens common in the Northern Italy semi-rural area where the patients lived, and with 10 mg/ml histamine dihydrochloride. RESULTS: We found higher histamine reactivity in allergic versus control individuals (median value 23.7 versus 19.8 mm2; p=0.0497). Likewise, we found in allergic subjects a correlation between allergen responsiveness in terms of number of positive allergens at skin prick test and sensitivity to histamine (mono- sensitized versus poly-sensitized subjects: p=0.0015). Moreover older age and male sex were associated with a higher response to histamine, also when separately considering allergic subjects (p<0.0001 in both cases: correlation coefficient for age versus histamine reactivity: r=0.3408). The correlation between allergen responsiveness and sensitivity to histamine was maintained also when statistically balanced for age and sex. CONCLUSION: Allergen responsiveness, gender and age allow more accurate prediction of histamine sensitivity than either parameter alone. (+info)Tolerance and immunological changes of chemically modified allergen vaccine of Parietaria judaica in accelerated schedules. (3/6)
The physicochemical modification of allergen vaccines provides a chance for administering higher doses in a shorter period of time. We sought to assess the safety and immunological changes of using a biologically standardized and modified Parietaria judaica pollen extract in accelerated schedules. Two accelerated schedules were tested in 45 P. judaica-allergic patients: 20 patients reached the maximum dose after two visits using two different concentrations and 25 patients reached the maximum dose after only one visit with two injections of the maximum concentration vial. The tolerance was assessed by recording all side effects related with immunotherapy. Specific antibody levels against native extract and rPar j 2 allergen were evaluated at the beginning and the end of the study. Allergenic potency determined by enzyme allergosorbent test (EAST) inhibition and skin prick test showed that modified P. judaica pollen had a 99.9% less allergenicity than native extract. After 650 doses administered, two clinically irrelevant local reactions (diameter<0 x 5 cm) and no systemic reactions were registered. Significant increases in allergen-specific IgG4 and IgG against P. judaica extract and rPar j 2 and significant decrease of specific IgE against Par j 2 were observed. The modified extract of P. judaica is safe to treat sensitive patients, even at accelerated regimens, and induces significant immunological changes. (+info)Associations among pollen sensitizations from different botanical species in patients living in the northern area of Madrid. (4/6)
OBJECTIVE: To determinate the existence of associations among sensitizations to antigens produced by pollen grains of different botanical species as assessed by skin prick tests in patients with respiratory disorders. METHODS: Six hundred twenty nine consecutive patients living in the northern area of Madrid who underwent clinical evaluation because of rhinoconjunctivitis, and/or asthma were studied. All patients were tested with a skin prick test using a battery of inhalants including pollens, dust mites, molds and danders. The exploratory multivariate technique of Multiple Correspondence Analysis was used to compare the homogeneity of sensitizations between groups. Of the 629 patients, 459 (73.0%) had positive skin prick tests to pollen and were selected as the study group. RESULTS: The most prevalent pollen sensitization was to Gramineae pollen (83.7%) followed by Oleaceae sensitisation (75.8%). Multiple Correspondence Analysis revealed the existence of an association among pollen sensitizations, showing that they clustered two groups: sensitizations to Gramineae, Oleaceae, Cupressaceae, Chenopodiaceae, Plantaginaceae (group I), and sensitizations to Betulaceae, Platanaceae, Compositae (group II). Sensitization to Parietaria was not included in any of the sensitization groups and showed an independent behaviour. CONCLUSION: Pollen sensitizations in our area cluster into two association groups which have not previously been reported. (+info)Expression patterns of HLA-DR+ or HLA-DR- on CD4+/CD25++/CD127low regulatory T cells in patients with allergy. (5/6)
BACKGROUND: Allergic rhinoconjunctivitis induced by pollen is a highly prevalent chronic inflammatory disease in Europe. Parietariajudaica is a frequent trigger in the Mediterranean area. The function of regulatory T cells (Treg cells) in allergy has recently been investigated, but further data are necessary to better understand their role and to find new strategies to treat allergic diseases such as allergic rhinoconjunctivitis. OBJECTIVE: To characterize gene expression of HLA-DR+ or HLA-DR- on peripheral CD4+/CD25++/CD127low Treg cells in patients with allergy. METHODS: Peripheral Treg cells (CD4+/CD25++/CD127low) were quantified using flow cytometry and sorted according to HLA-DR expression during the pollen season in patients with allergic rhinoconjunctivitis caused by P. judaica. The results were compared with those of nonatopic controls. Expression of associated cytokines and their receptors was measured using quantitative reverse transcription-polymerase chain reaction after extraction of mRNA in sorted populations. RESULTS: During the pollen season, no significant differences were observed between allergic patients with rhinoconjunctivitis and healthy controls in terms of the absolute number or the percentage of Treg cells in peripheral blood. All patients had a higher number/percentage of HLA-DR- Treg cells than HLA-DR+ Treg cells. In both groups we found high levels of FOXP3 mRNA expression. Despite being lower in number, HLA-DR+ Treg cells presented higher expression of CD28, PRF1, GZMB, and FASL than HLA-DR-Treg cells. CONCLUSIONS: The most relevant results obtained suggest that HLA-DR+ Treg cells tend to present higher gene expression of molecules associated with contact-dependent cell activation and cytotoxicity. (+info)Sublingual immunotherapy in polysensitized patients: effect on quality of life. (6/6)
BACKGROUND: Quality of life (QOL) is an important issue in allergic rhinitis and has been evaluated in a number of studies that have shown how it is impaired in untreated patients and improved by effective treatment. However, there are no data concerning QOL after sublingual immunotherapy (SLIT) in polysensitized patients. OBJECTIVE: To evaluate the effect, in real-life clinical practice, of SLIT on QOL in a population of polysensitized patients with allergic rhinitis. METHODS: We prospectively evaluated 167 consecutively enrolled polysensitized patients with allergic rhinitis. QOL was measured in all cases with the Rhinoconjunctivitis Quality of Life Questionnaire at baseline and after 1 year of SLIT (performed in approximately 70% of cases using single allergen extracts provided by the same manufacturer). RESULTS: The most frequent causes of sensitization were grass pollen, Parietaria, and house dust mites. The mean number of sensitizations per patient was 3.65. SLIT was performed with 1 extract in 123 patients (73.6%), with 2 extracts in 31 patients (18.6%), and with more than 2 extracts in 13 patients (7.8%). The mean values of all the QOL items improved significantly (P < .01 in all cases), with the following reductions noted: activities, 3.96 to 2.89; sleep, 2.07 to 1.56; general problems, 2.16 to 1.5; practical problems, 3.69 to 2.58; nasal symptoms, 3.57 to 2.50; eye symptoms, 2.92 to 1.83; and emotional aspects, 2.2 to 1.44. CONCLUSIONS: This study provides evidence that QOL can be improved in polysensitized patients treated with SLIT, and that the use of just 1 or 2 allergen extracts seems to be sufficient and effective in terms of improving QOL. (+info)'Parietaria' is a genus of flowering plants, also known as pellitory, which includes several species that can cause allergic reactions due to their tiny pollen grains and are often found growing in urban areas.
"Parietaria" is a genus of flowering plants in the nettle family, Urticaceae. Commonly known as pellitory-of-the-wall or wall pennywort, these plants are found in many parts of the world and are often considered to be weeds. They can grow in a variety of environments, including walls, rocks, and soil.
In a medical context, Parietaria species are not well known for their medicinal properties, but some studies suggest that they may have anti-inflammatory and antioxidant effects. Contact with the plants can cause skin irritation or allergic reactions in some people, due to the presence of tiny hairs on the leaves and stems that can release histamine and other chemicals.
It's worth noting that "Parietaria" is not a commonly used medical term, and it is more frequently encountered in botany and horticulture than in clinical medicine. If you have any specific concerns about allergic reactions or skin irritation related to Parietaria or any other plant, it's always best to consult with a healthcare professional for personalized advice and treatment.
'Pollen' is a fine to coarse powder containing male reproductive gametophytes which, when transferred to the stigma of a pistil, can lead to fertilization and subsequent seed production in seed plants.
Pollen, in a medical context, refers to the fine powder-like substance produced by the male reproductive organ of seed plants. It contains microscopic grains known as pollen grains, which are transported by various means such as wind, water, or insects to the female reproductive organ of the same or another plant species for fertilization.
Pollen can cause allergic reactions in some individuals, particularly during the spring and summer months when plants release large amounts of pollen into the air. These allergies, also known as hay fever or seasonal allergic rhinitis, can result in symptoms such as sneezing, runny nose, congestion, itchy eyes, and coughing.
It is important to note that while all pollen has the potential to cause allergic reactions, certain types of plants, such as ragweed, grasses, and trees, are more likely to trigger symptoms in sensitive individuals.
Allergens are substances that can induce an abnormal immune response, leading to allergic symptoms or diseases in susceptible individuals.
An allergen is a substance that can cause an allergic reaction in some people. These substances are typically harmless to most people, but for those with allergies, the immune system mistakenly identifies them as threats and overreacts, leading to the release of histamines and other chemicals that cause symptoms such as itching, sneezing, runny nose, rashes, hives, and difficulty breathing. Common allergens include pollen, dust mites, mold spores, pet dander, insect venom, and certain foods or medications. When a person comes into contact with an allergen, they may experience symptoms that range from mild to severe, depending on the individual's sensitivity to the substance and the amount of exposure.