Validation of novel recipes for masking peanuts in double-blind, placebo-controlled food challenges.

BACKGROUND: Double-blind, placebo-controlled oral food challenges are the gold standard in food allergy diagnosis. Nevertheless, proper masking of peanuts is particularly complex owing to their intense flavor and odor. Thus, it is important to use validated recipes to ensure their adequate masking during oral food challenges. OBJECTIVE: To design and validate recipes containing masked peanuts for double-blind, placebo-controlled oral food challenges. METHODS: Two types of products (cookies and a custard­type dessert) containing the masked peanuts and other ingredients with low allergenic potential were designed and validated. For this purpose, of the 24 initial cookie recipes and 12 initial custard recipes developed, those that did not exhibit significant differences in their texture were selected for sensory validation. RESULTS: Similarity triangle tests were performed using a panel of 36 selected tasters, enabling the validation of 1 pair of cookie recipes and 1 pair of custard-type dessert recipe, both with low allergenic potential and suitable for those with celiac disease and for vegans. CONCLUSION: The validated recipes are of clinical and research interest because they allow to confirm a peanut allergy and detect a wide range of tolerated threshold doses, which makes it possible to provide specific indications for each patient.

Secondary prevention measures in anaphylaxis patients: Data from the anaphylaxis registry.

BACKGROUND: Patients with a history of anaphylaxis are at risk of future anaphylactic reactions. Thus, secondary prevention measures are recommended for these patients to prevent or attenuate the next reaction. METHODS: Data from the Anaphylaxis Registry were analyzed to identify secondary prevention measures offered to patients who experienced anaphylaxis. Our analysis included 7788 cases from 10 European countries and Brazil. RESULTS: The secondary prevention measures offered varied across the elicitors. A remarkable discrepancy was observed between prevention measures offered in specialized allergy centers (84% of patients were prescribed adrenaline autoinjectors following EAACI guidelines) and outside the centers: Here, EAACI guideline adherence was only 37%. In the multivariate analysis, the elicitor of the reaction, age of the patient, mastocytosis as comorbidity, severity of the reaction, and reimbursement/availability of the autoinjector influence physician's decision to prescribe one. CONCLUSIONS: Based on the low implementation of guidelines concerning secondary prevention measures outside of specialized allergy centers, our findings highlight the importance of these specialized centers and the requirement of better education for primary healthcare and emergency physicians.

Preclinical Biokinetic Modelling of Tc-99m Radiophamaceuticals Obtained from Semi-Automatic Image Processing.

The aim of this study was to develop a semi automatic image processing algorithm (AIPA) based on the simultaneous information provided by X-ray and radioisotopic images to determine the biokinetic models of Tc-99m radiopharmaceuticals from quantification of image radiation activity in murine models. These radioisotopic images were obtained by a CCD (charge couple device) camera coupled to an ultrathin phosphorous screen in a preclinical multimodal imaging system (Xtreme, Bruker). The AIPA consisted of different image processing methods for background, scattering and attenuation correction on the activity quantification. A set of parametric identification algorithms was used to obtain the biokinetic models that characterize the interaction between different tissues and the radiopharmaceuticals considered in the study. The set of biokinetic models corresponded to the Tc-99m biodistribution observed in different ex vivo studies. This fact confirmed the contribution of the semi-automatic image processing technique developed in this study.

Lipid Transfer Protein Syndrome in a Non-Mediterranean Area.

BACKGROUND: Plant food allergies associated with lipid transfer protein (LTP) have been widely described in the Mediterranean Basin. OBJECTIVE: The aim of this work was to describe the clinical profile and pollen sensitization of plant food- allergic patients sensitized to LTP in a non-Mediterranean area. METHODS: Patients with clear IgE-mediated symptoms associated with plant foods and a positive skin prick test (SPT) to Pru p 3 were included in a prospective study in the north of Spain. Reported symptoms were analyzed together with a battery of food and pollen SPTs and specific IgE components by ISAC microarray. Cross-inhibition studies were performed by ImmunoCAP with plane tree, mugwort and rPru p 3. RESULTS: Among the 72 patients included, the most frequent food allergy reported was to peaches (69%) followed by nuts (walnuts 55%, peanuts 54% and hazelnuts 43%). Most patients suffered from symptoms with multiple plant foods (a median of 6 foods per patient). Regarding the patients' pollen sensitization, 36% were sensitized to mugwort pollen (72% showing sIgE to Art v 3), 33% to grass pollen and 24% to plane tree pollen (94% with sIgE to Pla a 3). Inhibition studies showed that specific IgEs against mugwort and plane tree pollen are inhibited by Pru p 3 in a strong manner, whereas Pru p 3 was less inhibited by pollen extracts. CONCLUSIONS: LTP syndrome occurs in a non-Mediterranean area and is related to multiple sensitizations to foods and pollens such as plane tree and mugwort. In these pollen sensitizations, Pru p 3 seems to be the primary sensitizer.

Hydrogels based on poly(ethylene glycol) as scaffolds for tissue engineering application: biocompatibility assessment and effect of the sterilization process.

Hydrogels are suitable materials to promote cell proliferation and tissue support because of their hydrophilic nature, porous structure and sticky properties. However, hydrogel synthesis involves the addition of additives that can increase the risk of inducing cytotoxicity. Sterilization is a critical process for hydrogel clinical use as a proper scaffold for tissue engineering. In this study, poly(ethylene glycol) (PEG), poly(ethylene glycol)-chitosan (PEG-CH) and multi-arm PEG hydrogels were synthesized by free radical polymerization and sterilized by gamma irradiation or disinfected using 70 % ethanol. The biocompatibility assessment in human fibroblasts and hemocompatibility studies (hemolysis, platelet aggregation, morphology of mononuclear cells and viability) in peripheral blood from healthy volunteers (ex vivo), were performed. The sterilization or disinfection effect on hydrogel structures was evaluated by FT-IR spectroscopy. Results indicated that hydrogels do not induce any damage to fibroblasts, erythrocytes, platelets or mononuclear cells. Moreover, there was no significant difference in the biocompatibility after the sterilization or disinfection treatment. However, after gamma irradiation, several IR spectroscopic bands were shifted to higher or lower energies with different intensity in all hydrogels. In particular, several bands associated to carboxyl or hydroxyl groups were slightly shifted, possibly associated to scission reactions. The disinfection treatment (70 % ethanol) and γ-irradiation at 13.83 ± 0.7 kGy did not induce morphological damages and yielded sterile and biocompatible PEG hydrogels potentially useful for clinical applications.

Optimal duration of allergen immunotherapy in children with dust mite respiratory allergy.

BACKGROUND: Subcutaneous immunotherapy (SCIT) discontinuation data in children remain scarce. OBJECTIVE: We sought for differences in the clinical efficacy of 3 vs. 5 yr of SCIT in children with dust mite respiratory allergy. METHODS: We performed a 5-yr, phase IV prospective study. After the first year, the patients were randomized to 3 (IT3) or 5 yr of treatment (IT5). Efficacy was assessed at 3rd and 5th year by symptom and medication scores and visual analog scales (VAS). Skin tests with common allergens and in vitro assessments were also performed. RESULTS: Eighty-one children (mean age: 9 yr) were randomly assigned to 3 (IT3: 41) or 5 yr (IT5: 40) of immunotherapy. After 3 years, rhinitis global scores decreased in IT3 (44%; p = 0.002) and in IT5 (50%; p = 0.001). Asthma global, symptom and medication scores decreased by 100% in IT3 (p = 0.001) and IT5 (p = 0.001). VAS scores also diminished significantly (IT3: 70%, p = 0.001; IT5: 62.5%; p = 0.001). At 5th year, global rhinitis scores were reduced an additional 30% in IT5 children. Comparisons between both groups did not show differences in rhinitis (p = 0.055), asthma global scores (p = 0.948) or VAS scores at 5th year. Twenty percent of IT5 (p = 0.002) and 7% of IT3 children (p = 0.705) developed new sensitizations. At 5th year, sIgG4 determinations decreased in IT3 without significant variations in IT5. CONCLUSIONS: Three years of SCIT induced significant improvement in children with dust mite respiratory allergy, but a 5-yr course added clinical improvement in rhinitis.

Two Novel Nanosized Radiolabeled Analogues of Somatostatin for Neuroendocrine Tumor Imaging.

The somatostatin receptors (SR), which are overexpressed in a majority of neuroendocrine tumors, are targets for radiopeptide-based imaging using for example the 99mTc-Tyr3-Octreotide peptide. Dendrimers are hyperbranched polymeric structures. The nanoscopic size and near-monodisperse nature properties give polyamidoamine (PAMAM) dendrimers an edge over linear polymers in the context of drug delivery. Gold nanoparticles (AuNPs) conjugated to peptides produces stable multimeric systems with target-specific molecular recognition. The aim of this research was to prepare two nanosized multimeric systems for neuroendocrine tumor imaging, 99mTc-PAMAM-Tyr3-Octreotide and 99mTc-AuNP-Tyr-Octreotide, and to compare their in vitro uptake in SR-positive AR42J cancer cells as well as their biodistribution profile in athymic mice bearing AR42J tumors. [Tyr3, Lys(Boc)5]-Octreotide was conjugated to the carboxylate groups of the PAMAM dendrimer (G3.5) with further Boc deprotection using TFA. 99mTc labeling was carried out by a direct method. 99mTc-Tyr3-Octreotide was conjugated to AuNPs (20 nm) by spontaneous reaction with the thiol group of cysteine. Radiochemical purity (RP) was determined by size-exclusion HPLC and ITLC-SG analyses. In vitro binding studies were carried out in AR42J cancer cells. Biodistribution studies were accomplished in athymic mice with AR42J-induced tumors with blocked and unblocked receptors. Elemental analysis demonstrated that 26 Tyr3-Octreotide molecules were successfully conjugated to one molecule of PAMAM. RP for both nanosized conjugates was > 94% and showed recognition for SR in AR42J cells. The tissue distribution of radioactivity 2 h after 99mTc-PAMAM-Tyr3-Octreotide administration in mice showed specific tumor uptake (4.12 ± 0.57% of injected dose/g) and high accumulation in the pancreas (15.08 ± 3.11% of injected dose/g) which expresses SR. No significant difference in the tumor uptake was found between 99mTc-PAMAM-Tyr3-Octreotide and 99mTc-AuNP-Tyr3-Octreotide. However, the dendrimer-peptide conjugate showed a significant renal excretion. Both radiopharmaceuticals demonstrated properties suitable for use as target-specific agents for molecular imaging of tumors that overexpressed SR.

Comparative Effect Between Laser and Radiofrequency Heating of RGD-Gold Nanospheres on MCF7 Cell Viability.

Gold nanoparticles conjugated to cyclo-[Arg-Gly-Asp-D-Phe-Lys(Cys)] peptides (AuNP-c[RGDfK(C)]) have been reported as systems with specific cell internalization in breast cancer cells. AuNPs have also been proposed as localized heat sources for cancer treatment using laser irradiation or radiofrequency (RF). The aim of this research was to analyze, based on the Mie theory, the AuNP-c[RGDfK(C)] absorption cross-sections (C(abs)) of low-frequency electromagnetic waves (13.56 MHz, λ = 22 m) and optical frequency waves (laser at λ = 532 nm) and to compare their effect on MCF7 cell viability as thermal conversion sources in AuNPs (20 nm) located inside cells. Cell viability was assessed in MCF7 cells treated with AuNP-c[RGDfK(C)] or water after exposure to the RF field (200 W, 100 V/cm) or laser irradiation (Irradiance 0.65 W/cm2). In both cases (RF and laser) the presence of nanoparticles in cells caused a significant increase in the temperature of the medium (RF: AT = 29.9 ± 1.7 degrees C for AuNP compared to ΔT = 13.0 ± 1.4 degrees C for water; laser: ΔT = 13.5 ± 0.7 degrees C for AuNP compared to 3.3 ± 0.5 degrees C for water). Although RF induced a higher increase in the temperature of the medium with nanoparticles, the largest effect on the cell viability was produced by laser when nanoparticles were located inside the cells (8.7?0.7% for laser compared to 19.4 ± 0.9% for RF). The differences obtained in C(abs) values (laser: 3.7 x 10- (16) m2; RF: 7.9 x 10-(23) m2) and the observed effect on MFC7 cell viability support two mechanisms previously proposed "wave energy absorption by AuNPs" when laser is used as a thermal conversion source, and "attenuation of the wave passing through the AuNP suspension" when RF is applied. The AuNP-c[RGDfK(C)] nanosystem shows suitable properties to improve hyperthermia treatments under laser irradiation due to a larger heat release inside cells.

Food-Induced Anaphylaxis: Data From the European Anaphylaxis Registry.

BACKGROUND: Food is one of the most common elicitors of anaphylaxis, with an increasing incidence over recent years. OBJECTIVES: To characterize elicitor-specific phenotypes and identify factors enhancing the risk or severity of food-induced anaphylaxis (FIA). METHODS: We analyzed data from the European Anaphylaxis Registry applying an age- and sex-matched analysis of associations (Cramer's V) for single food triggers and calculated odds ratios (ORs) for severe FIA. RESULTS: We identified 3,427 cases of confirmed FIA showing an age-dependent elicitor ranking (for children: peanut, cow's milk, cashew, and hen's egg; and for adults: wheat flour, shellfish, hazelnut, and soy). The age- and sex-matched analysis revealed defined symptom patterns for wheat and cashew. Wheat-induced anaphylaxis was more frequently associated with cardiovascular symptoms (75.7%; Cramer's V = 0.28) and cashew-induced anaphylaxis with gastrointestinal symptoms (73.9%; Cramer's V = 0.20). Furthermore, concomitant atopic dermatitis was slightly associated with anaphylaxis to hen's egg (Cramer's V = 0.19) and exercise was strongly associated with anaphylaxis to wheat (Cramer's V = 0.56). Additional factors influencing the severity were alcohol intake in wheat anaphylaxis (OR = 3.23; CI, 1.31-8.83) and exercise in peanut anaphylaxis (OR = 1.78; CI, 1.09-2.95). CONCLUSIONS: Our data show that FIA is age-dependent. In adults, the range of elicitors inducing FIA is broader. For some elicitors, the severity of FIA seems to be related to the elicitor. These data require confirmation in future studies considering a clear differentiation between augmentation and risk factors in FIA.

Three years of specific immunotherapy may be sufficient in house dust mite respiratory allergy.

BACKGROUND: Specific immunotherapy (SIT) duration for respiratory allergy is currently based on individual decisions. OBJECTIVE: To evaluate the differences in clinical efficacy of SIT as a result of the duration between the current recommended limits (3-5 years). METHODS: A 5-year prospective, controlled clinical trial of SIT blind until the first year and randomization to a 3-year (IT3) or 5-year (IT5) course was conducted. Of the 239 patients with respiratory allergy caused by D pteronyssinus initially included, 142 completed 3 years of SIT with good compliance. Twenty-seven controls were included at the third year. Efficacy of SIT after 3 (T3) and 5 (T5) years was assessed by using clinical scores, visual analog scales (VASs), rhinitis (RQLQ) and asthma (AQLQ) quality of life questionnaires, skin tests, and serum immunoglobulins. RESULTS: At T3, significant reductions were observed in rhinitis (44% in IT3 and 50% in IT5; P < .001), asthma (80.9 % in IT3 and 70.9% in IT5; P < .001) scores, VAS (P < .001 in both), RQLQ (P < .001 in both) and AQLQ (P < .001 in both). At T5, the clinical benefit was maintained in both groups, and IT5 patients presented additional decreases (19%; P = .019) in rhinitis scores. At Tf, specific IgG(4) measurements were lower in IT3 (P = .03) without detecting differences in IT5. An increase in asthma score of 133% was the only difference observed in controls. CONCLUSION: Clinical improvement is obtained with 3 years of D pteronyssinus SIT. Two additional years of SIT add clinical benefit in rhinitis only.

Nanocarriers for delivery of siRNA as gene silencing mediator.

The term nanocarrier refers to sub-micrometric particles of less than 100 nm, designed to transport, distribute, and release nanotechnology-based drug delivery systems. siRNA therapy is a novel strategy that has great utility for a variety of treatments, however naked siRNA delivery has not been an effective strategy, resulting in the necessary use of nanocarriers for delivery. This review aims to highlight the versatility of carriers based on smart drug delivery systems. The nanocarriers based on nanoparticles as siRNA DDS have provided a set of very attractive advantages related to improved physicochemical properties, such as high surface-to-volume ratio, versatility to package siRNA, provide a dual function to both protect extracellular barriers that lead to elimination and overcome intracellular barriers limiting cytosolic delivery, and possible chemical modifications on the nanoparticle surface to improve stability and targeting. Lipid and polymeric nanocarriers have proven to be stable, biocompatible, and effective in vitro, further exploration of the development of new nanocarriers is needed to obtain safe and biocompatible tools for effective therapy.

Multimeric system of 99mTc-labeled gold nanoparticles conjugated to c[RGDfK(C)] for molecular imaging of tumor α(v)ß(3) expression.

Integrin α(V)ß(3) plays a critical role in tumor angiogenesis and metastasis. Suitably radiolabeled cyclic RGD peptides can be used for noninvasive imaging of α(V)ß(3) expression. The aim of this research was to prepare a multimeric system of technetium-99m-labeled gold nanoparticles conjugated to c[RGDfK(C)] and to evaluate its biological behavior as a potential radiopharmaceutical for molecular imaging of tumor angiogenesis. Hydrazinonicotinamide-GGC (HYNIC-GGC) and c[RGDfK(C)] peptides were synthesized and conjugated to gold nanoparticles (AuNP, 20 nm) by means of spontaneous reaction of the thiol groups of cysteine. The nanoconjugate was characterized by TEM, FT-IR, UV-vis, XPS, and Raman spectroscopy. To obtain (99m)Tc-HYNIC-GGC-AuNP-c[RGDfK(C)] ((99m)Tc-AuNP-RGD), the (99m)Tc-HYNIC-GGC radiopeptide was first prepared and added to 1.5 mL of AuNP solution (1 nM) followed by c[RGDfK(C)] (10 µL, 50 µM) at 18 °C with stirring for 15 min. Radiochemical purity (RP) was determined by size-exclusion HPLC and ITLC-SG analyses. In vitro binding studies were carried out in α(V)ß(3) receptor-positive C6 glioma cancer cells. Biodistribution studies were accomplished in athymic mice with C6-induced tumors with blocked and nonblocked receptors, and images were obtained using a micro-SPECT/CT. TEM and spectroscopy techniques demonstrated that AuNPs were functionalized with peptides. RP was 96 ± 2% without postlabeling purification. (99m)Tc-AuNP-RGD showed specific recognition for α(V)ß(3) integrins expressed in C6 cells, and 3 h after i.p. administration in mice, the tumor uptake was 8.18 ± 0.57% ID/g. Micro-SPECT/CT images showed evident tumor uptake. (99m)Tc-AuNP-RGD demonstrates properties suitable for use as a target-specific agent for molecular imaging of tumor α(V)ß(3) expression.

Wheat Anaphylaxis in Adults Differs from Reactions to Other Types of Food.

BACKGROUND: Wheat is one of the most commonly consumed foods and a known elicitor of anaphylaxis in children and adults. Reactions in adults are often cofactor dependent and characterized by a prolonged time between food intake and the onset of symptoms making the diagnosis of wheat anaphylaxis challenging. OBJECTIVE: To characterize a cohort of patients with the history of wheat anaphylaxis to better understand this atypical phenotype of anaphylaxis. METHODS: Data from the European Anaphylaxis Registry from 2007 to 2019 (n = 10,636) including 250 patients (213 adults and 37 children) with a history of anaphylaxis caused by wheat were analyzed. RESULTS: Wheat was the most common food elicitor of anaphylaxis in adults in the registry in Central Europe. Reactions to wheat in adults were frequently associated with exercise as a cofactor (82.8%) and partially delayed (57.5%). Only 36.9% of patients had atopic comorbidities, which was uncommonly low for adult patients allergic to other kinds of foods (63.2%). Anaphylaxis to wheat presented frequently with cardiovascular symptoms (86.7%) including severe symptoms such as loss of consciousness (41%) and less often with respiratory symptoms (53.6%). The reactions to wheat were more severe than reactions to other foods (odds ratio [OR] = 4.33), venom (OR = 1.58), or drugs (OR = 2.11). CONCLUSIONS: Wheat is a relevant elicitor of anaphylaxis in adults in Central Europe. Wheat anaphylaxis is highly dependent on the presence of cofactors and less frequently associated with atopic diseases compared with other food allergies. More data on mechanisms of wheat-induced anaphylaxis are required to develop preventive measures for this potentially life-threatening disease.

Differences among pollen-allergic patients with and without plant food allergy.

BACKGROUND: A considerable number of pollen-allergic patients develops allergy to plant foods, which has been attributed to cross-reactivity between food and pollen allergens. The aim of this study was to analyze the differences among pollen-allergic patients with and without plant food allergy. METHODS: Eight hundred and six patients were recruited from 8 different hospitals. Each clinical research group included 100 patients (50 plant food-allergic patients and 50 pollen-allergic patients). Diagnosis of pollen allergy was based on typical case history of pollen allergy and positive skin prick tests. Diagnosis of plant-food allergy was based on clear history of plant-food allergy, skin prick tests and/or plant-food challenge tests. A panel of 28 purified allergens from pollens and/or plant foods was used to quantify specific IgE (ADVIA-Centaur® platform). RESULTS: Six hundred and sixty eight patients (83%) of the 806 evaluated had pollen allergy: 396 patients with pollen allergy alone and 272 patients with associated food and pollen allergies. A comparison of both groups showed a statistically significant increase in the food and pollen allergy subgroup in frequency of: (1) asthma (47 vs. 59%; p < 0.001); (2) positive skin test results to several pollens: Plantago, Platanus, Artemisia, Betula, Parietaria and Salsola (p < 0.001); (3) sensitization to purified allergens: Pru p 3, profilin, Pla a 1 - Pla a 2, Sal k 1, PR-10 proteins and Len c 1. CONCLUSION: Results showed relevant and significant differences between both groups of pollen-allergic patients depending on whether or not they suffered from plant-derived food allergy.

Risk Factors and Characteristics of Biphasic Anaphylaxis.

BACKGROUND: Anaphylaxis is an immediate hypersensitivity reaction. However, a biphasic course with the second onset of symptoms can occur hours after the initial phase. Little is known about the causes of biphasic anaphylaxis making the identification of patients at risk difficult. OBJECTIVE: To identify factors predisposing for biphasic anaphylaxis for the better understanding of these reactions. METHODS: Data from the Anaphylaxis Registry (from 11 countries) including 8736 patients with monophasic and 435 biphasic anaphylaxis were analyzed. RESULTS: The rate of biphasic reactions in this large cohort was 4.7%. The identified risk factors were reaction severity (grade III/IV vs grade II: odds ratio [OR] = 1.34; 95% confidence interval [CI]: 1.1-1.62); multiorgan involvement; skin, gastrointestinal, severe respiratory, and cardiac symptoms; anaphylaxis caused by peanut/tree nut (OR = 1.78; 95% CI: 1.38-2.23) or an unknown elicitor (OR = 1.96; 95% CI: 1.41-2.72); exercise as a cofactor (OR = 1.44; 95% CI: 1.17-1.78); chronic urticaria as a comorbidity (OR = 2.12; 95% CI: 1.19-3.78); a prolonged interval between the contact with the elicitor and start of primary symptoms (OR for >30 vs <30 min: 1.38; 95% CI: 1.08-1.76); and antihistamine treatment (OR = 1.52; 95% CI: 1.14-2.02). CONCLUSION: A biphasic course of anaphylaxis occurs more frequently in severely affected patients with multiorgan involvement. However, we identified multiple additional predictors, suggesting that the pathogenesis of biphasic reactions is more complex than being a rebound of a severe primary reaction.

Refractory Anaphylaxis: Data From the European Anaphylaxis Registry.

Refractory anaphylaxis (unresponsive to treatment with at least two doses of minimum 300 µg adrenaline) is a rare and often fatal hypersensitivity reaction. Comprehensive data on its definition, prevalence, and risk factors are missing. Using the data from the European Anaphylaxis Registry (11,596 cases in total) we identified refractory anaphylaxis cases (n = 42) and analyzed these in comparison to a control group of severe anaphylaxis cases (n = 4,820). The data show that drugs more frequently elicited refractory anaphylaxis (50% of cases, p < 0.0001) compared to other severe anaphylaxis cases (19.7%). Cases elicited by insects (n = 8) were more often due to bees than wasps in refractory cases (62.5 vs. 19.4%, p = 0.009). The refractory cases occurred mostly in a perioperative setting (45.2 vs. 9.05, p < 0.0001). Intramuscular adrenaline (as a first line therapy) was administered in 16.7% of refractory cases, whereas in 83.3% of cases it was applied intravenously (significantly more often than in severe anaphylaxis cases: 12.3%, p < 0.0001). Second line treatment options (e.g., vasopression with dopamine, methylene blue, glucagon) were not used at all for the treatment of refractory cases. The mortality rate in refractory anaphylaxis was significantly higher (26.2%) than in severe cases (0.353%, p < 0.0001). Refractory anaphylaxis is associated with drug-induced anaphylaxis in particular if allergens are given intravenously. Although physicians frequently use adrenaline in cases of perioperative anaphylaxis, not all patients are responding to treatment. Whether a delay in recognition of anaphylaxis is responsible for the refractory case or whether these cases are due to an overflow with mast cell activating substances-requires further studies. Reasons for the low use of second-line medication (i.e., methylene blue or dopamine) in refractory cases are unknown, but their use might improve the outcome of severe refractory anaphylaxis cases.

Preparation and in vitro evaluation of radiolabeled HA-PLGA nanoparticles as novel MTX delivery system for local treatment of rheumatoid arthritis.

Radiosynovectomy is a technique used to decrease inflammation of the synovial tissue by intraarticular injection of a ß-emitting radionuclide, such as 177Lu, which is suitable for radiotherapy due to its decay characteristics. Drug-encapsulating nanoparticles based on poly lactic­co­glycolic acid (PLGA) polymer are a suitable option to treat several arthritic diseases, used as anti-inflammatory drugs transporters of such as methotrexate (MTX), which has been widely used in the arthritis treatment (RA), and hyaluronic acid (HA), which specifically binds the CD44 and hyaluronan receptors overexpressed on the inflamed synovial tissue cells. The 1,4,7,10­Tetraazacyclododecane­1,4,7,10­tetraacetic acid (DOTA) was used as complexing agent of Lutetium-177 for radiotherapy porpoises. The aim of this research was to synthesize 177Lu-DOTA-HA-PLGA(MTX) as a novel, smart drug delivery system with target-specific recognition, potentially useful in radiosynovectomy for local treatment of rheumatoid arthritis. The polymeric nanoparticle system was prepared and chemically characterized. The MTX encapsulation and radiolabelling were performed with suitable characteristics for its in vitro evaluation. The HA-PLGA(MTX) nanoparticle mean diameter was 167.6 nm ±â€¯57.4 with a monomodal and narrow distribution. Spectroscopic techniques demonstrated the effective conjugation of HA and chelating agent DOTA to the polymeric nanosystem. The MTX encapsulation was 95.2% and the loading efficiency was 6%. The radiochemical purity was 96 ±â€¯2%, determined by ITLC. Conclusion: 177Lu-DOTA-HA-PLGA(MTX) was prepared as a biocompatible polymeric PLGA nanoparticle conjugated to HA for specific targeting. The therapeutic nanosystem is based on bi-modal mechanisms using MTX as a disease-modifying antirheumatic drug (DMARD) and 177Lu as a radiotherapeutic component. The 177Lu-DOTA-HA-PLGA(MTX) nanoparticles showed properties suitable for radiosynovectomy and further specific targeted anti-rheumatic therapy.

[99mTc-HYNIC-N-dodecylamide]: a new hydrophobic tracer for labelling reconstituted high-density lipoproteins (rHDL) for radioimaging.

Despite the widespread use of nanotechnology in radio-imaging applications, lipoprotein based delivery systems have received only limited attention so far. These studies involve the synthesis of a novel hydrophobic radio-imaging tracer consisting of a hydrazinonicotinic acid (HYNIC)-N-dodecylamide and 99mTc conjugate that can be encapsulated into rHDL nanoparticles (NPs). These rHDL NPs can selectively target the Scavenger Receptor type B1 (SR-B1) that is overexpressed on most cancer cells due to excess demand for cholesterol for membrane biogenesis and thus can target tumors in vivo. We provide details of the tracer synthesis, characterization of the rHDL/tracer complex, in vitro uptake, stability studies and in vivo application of this new radio-imaging approach.