Shrimp Allergy: Analysis of Commercially Available Extracts for In Vivo Diagnosis.

BACKGROUND AND OBJECTIVE: Skin prick testing (SPT) with commercial extracts is the first step in the diagnosis of shrimp allergy, although its clinical efficiency is unknown. Objective: To analyze the clinical usefulness of all commercial crustacean extracts available for SPT in Italy. METHODS: We performed a multicenter study of 157 shrimp-allergic patients who underwent SPT with 5 commercial crustacean extracts and with house dust mite (HDM) extract. Commercial extracts were analyzed using SDS-PAGE and compared with a freshly prepared in-house shrimp extract. IgE to Pen a 1/Pen m 1, Pen m 2, and Pen m 4 was determined, and immunoblot analysis was performed on a large number of sera. RESULTS: The skin reactions caused by commercial crustacean extracts were extremely heterogeneous, resulting in 32 clinical profiles, with marked differences in protein content and missing proteins at molecular weights corresponding to those of major shrimp allergens. Only strong Pen a 1/Pen m 1 reactors reacted to both HDM and all 5 commercial extracts in SPT. Most patients, including those who were tropomyosin-negative, reacted to HDM. Patients reacted to a large and variable array of proteins, and IgE reactivity was common at high molecular weights (>50 kDa). CONCLUSIONS: The in vivo diagnosis of shrimp allergy must continue to be based on SPT with fresh material. Shrimp-allergic patients frequently react to a number of ill-defined high-molecular-weight allergens, thus leaving currently available materials for component-resolved diagnosis largely insufficient. Mites and crustaceans probably share several allergens other than tropomyosin.

Anaphylactic reaction after the concomitant intravenous administration of corticosteroids and gastroprotective drugs: two case reports.

Corticosteroids are therapeutic drugs widely used in cases of allergic, inflammatory and autoimmune diseases, but sometimes allergic hypersensitivity reactions have been reported as a rare adverse effect of the corticosteroids themselves. Moreover, glucocorticoids can induce gastric lesions; that’s why they are sometimes administered intravenously together with some drugs such as proton pump inhibitors (PPI) or inhibitors of histamine-2 receptors (antiH2) working as gastric protectors. Although it is difficult to establish which drug was responsible in case of hypersensitivity reactions, as hypersensitivity reactions following to the use of PPI or anti-H2 have been already described in literature. Here we describe two cases of immediate-type hypersensitivity triggered from the administration of a corticosteroid plus a gastroprotective agent and the diagnostic check up required in both these patients.

Use of a rapid and simple method to extract proviral DNA in the identification of HIV-1 by PCR.

DNA extraction is a critical step in PCR analysis and is closely related to its sensitivity. Traditional methods, based on phenol-chloroform extraction, require more time and the use of toxic reagents. GeneReleaser (Bio Ventures Inc.) is a commercial product which releases DNA from whole blood, cell cultures, bacterial colonies and the like. Cells lysis and DNA extraction are accomplished directly in the amplification tube on a thermocycler. We used GeneReleaser in the identification of HIV-1 proviral DNA by PCR on whole blood samples. All samples arrived at our laboratory for HIV-1 detection were treated with two different procedures. The classical one was based on the lysis of separated lymphocytes by proteinase K, while the other consisted in DNA extraction by GeneReleaser from 5 microliters of whole blood in sodium citrate. All samples were amplified for HIV-1 GAG region; to prevent carry-over contamination Uracil N-glycosylase (UNG) sterilization was performed. Amplified sequences were revealed using the DEIA commercial system (Sorin Biomedica, Italy). To verify the suitability both of cell lysates and GeneReleaser DNA-extracted samples for PCR, we amplified a specific sequence of HLA-DQ-alpha gene. Initial data indicate that this new method might reduce the performance time of PCR (DNA extraction time was around 15 minutes) and improve PCR sensitivity.

Seborrheic dermatitis and daylight.

Patients with mood depression have been found to have a higher prevalence of seborrheic dermatitis (SD), possibly related to their tendency to live indoors. The prevalence of outpatients with SD has now been found to be directly related to the number of gloomy days in the area. Since UV light might not be the only reason for the well-known improvement in SD in summer, an explanation possibly related to melatonin is envisaged.

Keratosis pilaris decalvans non-atrophicans.

A patient is described who presented with an eruption of tiny follicular keratotic papules on the limbs and the trunk accompanied by profuse hair loss. Histologically, a diagnosis of keratosis pilaris was made. The eruption cleared spontaneously in 3 months with complete regrowth of hair. Neither atrophy nor scarring remained. This appears to be the first reported case of keratosis pilaris decalvans non-atrophicans.

Patients with mood depression have a high prevalence of seborrhoeic dermatitis.

Prevalence and severity of seborrhoeic dermatitis were studied in 150 patients with psychiatric disorders, including schizophrenia, mood disorders, anxiety and organic mental illness. As a control group, we examined 150 patients waiting for surgery and regarded as obviously anxious. Thirty-eight psychiatric patients were found to have seborrhoeic dermatitis, versus 13 in the surgery group. This statistically significant difference was entirely ascribable to patients with depression.

Retinoic acid treatment induces apoptosis or expression of a more differentiated phenotype on different fractions of cultured fetal rat hepatocytes.

The present study reports the effects of retinoic acid (RA) on cultured fetal rat hepatocytes. We show that RA treatment induces both differentiation and apoptosis. Hepatocytes cultured for 48 hours in the presence of 5 microl/L RA form junctional complexes in the areas of contact between neighboring cells and develop bile canaliculi, typical features of mature and well-differentiated cells. At the same time, about 20% of cells are induced to die by apoptosis, and the percentage of apoptotic cells increases according to the concentration of RA used and the duration of treatment. The induction of apoptosis, studied at the morphological and biochemical levels, revealed that, in our system, the classical compaction of chromatin occurs only during the final stages of the process; instead of the common marker of apoptosis, i.e., the "DNA ladder" pattern of fragmentation, megabase-sized fragments were found. These observations provide further evidence of the existence of fundamental differences in the mechanisms of apoptosis among cell types. To investigate the molecular mechanism of the effects of RA, we evaluated the expression of two proteins, c-myc and p53, which are known to be involved in both cell differentiation and apoptosis. The data obtained show that the amount of p53 remained unchanged after RA treatment. On the contrary, a dose-dependent reduction in c-myc levels was found, suggesting that RA action may be mediated by modulation of this oncogene. Our findings regarding the apoptosis-inducing effect of RA, which was not found in adult hepatocytes, suggest a possible relationship between this phenomenon and the proliferative capacity and/or differentiation state of hepatocytes.

Modulation of cell surface expression of liver carbohydrate receptors during in vivo induction of apoptosis with lead nitrate.

Cell surface expression of carbohydrate receptors (i.e. mannose and galactose receptors) and phagocytosis of apoptotic cells by sinusoidal liver cells was studied. Binding sites and phagocytic activity were quantified at different time intervals (1, 3, 5, 7, 9, 11, 13, 15, 20, 30, 40 and 60 days) after the in vivo administration to rats of a potent liver mitogen, lead nitrate, that also induces apoptosis. The number and distribution of binding sites was receptor and cell-type dependent during the days following the metal injection. The use of competing saccharides in inhibition uptake experiments suggests that sinusoidal liver cells actively phagocytose apoptotic hepatocytes and circulating apoptotic cells by using both receptors. In particular, Kupffer cells at 5 and 15 days after the lead nitrate injection are very active in internalizing apoptotic cells (two- to threefold control). However, phagosomes containing apoptotic hepatocytes are often seen inside the cytoplasm of parenchymal and endothelial cells.

Leucocyte identification and analysis in human semen.

The analysis of leucocyte population in human semen could be useful in the diagnosis and therapeutic monitoring of male genital infections, but it is difficult due the low percentage of leucocytes, often not easily recognizable from immature cells of spermatogenesis. A method was developed for the isolation and identification of different leucocyte populations in human semen in healthy subjects using anti-CD45-covered magnetic beads. The seminal fluid was incubated with anti-CD45-covered magnetic beads and the samples were placed in contact with a magnet. The CD45-positive cells recovered were analyzed by light microscopy. The leucocyte formula was compared with a leucocyte formula performed on seminal fluid sediment. The method, even if laborious, eliminates all spermatozoa and most of cells of spermatogenetic lineage, thus permitting phenotyping and functional analysis on isolated leucocytes.

IgE responses to Dermatophagoides pteronyssinus native major allergens Der p 1 and Der p 2 during long-term specific immunotherapy.

We investigated by ELISA the IgE response to whole extract of the house-dust mite Dermatophagoides pteronyssinus (Dp) and to the native major allergens, Der p 1 and Der p 2, in sera from 18 adult patients (group A) with Dp-allergic asthma before (t0) and 1, 2, 3, and 4 (t1-t4) years after subcutaneous specific immunotherapy (SIT). A qualitative reduction (P = 0.05) of the IgE responses to Dp and Der p 2 was observed from t1 to t4, but a highly statistical significant decrease appeared at t3 (P < 0.01). With regard to Der p 1 IgE values, the immunotherapy induced a significant decrease (P < 0.01) at t3, but not before. In group A, the IgE responses to Der p 1 and Der p 2 were not correlated at t0 (rs = 0.31; P = 0.21) but were correlated at t3 (rs = 0.78; P = 0.001). We also examined sera from 14 adult patients (group B, same SIT schedule as group A) who were without respiratory symptoms at the end of the third year (t3) of Dp SIT. At this time (t3), there were no significant differences in Der p 1 and Der p 2 IgE levels between group A and group B.