A hybrid molecule resembling the epitope spectrum of grass pollen for allergy vaccination

BACKGROUND: Allergy vaccines based on natural allergen extracts contain greatly varying amounts of individual allergens with different immunogenicity. OBJECTIVE: To develop a novel type of allergy vaccine for complex allergen sources that combines defined amounts of the major allergens in the form of single hybrid molecules. METHODS: A hybrid molecule was engineered by PCR-based mending and expression of the cDNAs coding for the 4 major grass pollen allergens and compared with its single components by circular dichroism analysis, T-cell proliferation, ELISA competition, and histamine release assays. Immune responses to the hybrid molecule were studied in BALB/c mice and rat basophil leukemia assays. RESULTS: The hybrid contained most of the B-cell epitopes of grass pollen and could be used to diagnose allergy in 98% (n = 652) of patients allergic to grass pollen. Immunization of mice and rabbits with the hybrid induced stronger and earlier IgG antibody responses than equimolar mixtures of the components, which can be explained by the induction of stronger T-cell responses by the hybrid versus the individual components. IgG antibodies induced by vaccination with the hybrid blocked immediate allergic reactions, as demonstrated by rat basophil degranulation assays in a murine model of grass pollen allergy. CONCLUSION: We demonstrate for grass pollen allergy that recombinant hybrid molecules covering the spectrum of the disease-eliciting epitopes of complex allergen sources can be engineered.     

Synthesis and structure-activity relationships of 7-substituted 3-(2, 6-dichlorophenyl)-1,6-naphthyridin-2(1H)-ones as selective inhibitors of pp60(c-src)

7-substituted 3-(2,6-dichlorophenyl)-1,6-naphthyridin-2(1H)-ones are potent inhibitors of protein tyrosine kinases, with some selectivity for c-Src. The compounds were prepared by condensing 4, 6-diaminonicotinaldehyde with 2,6-dichlorophenylacetonitrile and selectively converting the 2- and 7-amino groups of the product to hydroxy and fluoro groups, respectively, by prolonged diazotization in 50% aqueous fluoboric acid. N-Methylation, followed by treatment with aliphatic diamines, aromatic amines, or their derived lithium anions, gave the desired compounds. Selected isomeric 1, 8-naphthyridin-2(1H)-ones were also prepared in order to evaluate the relative contributions of both ring A aza atoms of the related pyrido[2,3-d]pyrimidin-7(8H)-ones to the inhibitory activity. The compounds were evaluated for their ability to prevent phosphorylation of a model substrate by c-Src, FGF-1 receptor, and PDGF-beta receptor enzymes. Overall, there was a high degree of correlation of the activities against the different kinases, with c-Src being generally the most sensitive to structural changes. 1, 6-Naphthyridin-2(1H)-one analogues bearing basic aliphatic side chains [7-NH(CH(2))(n)()NRR, 7-NHPhO(CH(2))(n)()NRR, or 7-NHPhN(CH(2))(4)NMe] were the most potent against c-Src (IC(50)s of 10-80 nM), showing good selectivity with respect to PDGFR (10-300-fold) but less with respect to FGFR. The 1, 6-naphthyridin-2(1H)-ones showed broadly similar activity to the analogous pyrido[2,3-d]pyrimidin-7(8H)-ones, whereas the 1, 8-naphthyridin-2(1H)-ones were at least 10(3)-fold less potent. These results, indicating that the 3-aza atom in the pyrido[2, 3-d]pyrimidin-7(8H)-ones is mandatory, whereas the 1-aza atom is not, support the published binding model for these compounds to c-Src (J. Med. Chem. 1998, 41, 1752), where the 3-aza and 2-NH atoms form a bidentate H-bond donor-acceptor motif that interacts with Met341 and the 1-aza atom is not involved in specific binding interactions.     

Quality of life (QOL) assessment of MIP (mitomycin, ifosfamide and cisplatin) chemotherapy in advanced non-small cell lung cancers (NSCLC)

BACKGROUND: Quality of life (QOL) assessment has emerged to measure and quantify the balance between treatment benefit and toxicity, and has a value in predicting response and overall survival in cancer patients. METHODS: From July 1995 to February 1997, 38 symptomatic patients with advanced non-small cell lung cancer (NSCLC) were treated with MIP chemotherapy (mitomycin 6 mg/m2, ifosfamide 3000 mg/m2 and cisplatin 50 mg/m2 on day 1 every 3 weeks). Patients were assessed for QOL including physical well-being, general symptoms and lung cancer-specific symptoms, as well as objective response. RESULTS: The overall response rate was 38.9% (14/36, all were partial response) and the median duration of response was 3.5 months [95% confidence interval (CI) 2.0-4.0]. The median duration of overall survival was 7 months (95% CI 5.9-8.5). The overall improvement of QOL was 58.3% with 21 patients feeling better on treatment. The toxicity of chemotherapy was mild, mainly nausea/vomiting and minimal alopecia. Using multiple clinical predictors of survival (age, histology, stage, performance status), only change of QOL emerged significantly (P = 0.0007). CONCLUSIONS: MIP had an endurable response and low toxicity profile, and provided good QOL. Integral QOL data in our study provided the strong prediction of survival in advanced NSCLC. Further experienced QOL study will provide greatly enhanced outcome data in clinical trials.      

Supraphysiological acetaldehyde levels suppress growth in chicken embryos.

Although exposure to ethanol is known to cause growth inhibition in a developing embryo, the contributing effect of acetaldehyde on growth is not as well documented. In this study, we measured acetaldehyde-induced growth suppression in three different chicken strains: Peterson x Hubbard, HY x Hubbard, and W36 Ginther White Leghorn. The chicken embryo provides a useful model for studying fetal alcohol syndrome (FAS) and has been used extensively in our laboratory. The current study was undertaken to determine whether the chicken embryo could serve as a model for studying the effects of acetaldehyde on growth. Acetaldehyde caused a significant reduction in embryonic weights only at the higher acetaldehyde concentrations. Torso-to-head ratios were unchanged at every acetaldehyde dose for all strains, supporting the suggestion that acetaldehyde-induced growth suppression was generalized in all tissues, rather than being exhibited as a selective decrease of neuronal tissue. All strains experienced a significant decrease in viability only at higher acetaldehyde concentrations, but differences in viability were evident among the strains. These results support findings obtained from previous work done on ethanol-induced differences among chicken strains by supporting the suggestion that the strain of chicken is important when studying the effects of teratogens on growth and viability. More importantly, the supraphysiological concentrations of acetaldehyde necessary to induce growth suppression seem to indicate that the chicken embryo may not be a viable model of FAS for studying the direct effects of acetaldehyde on embryonic growth.     

Toxicity assessment of fumonisins using the brine shrimp (Artemia salina) bioassay.

The Fusarium mycotoxins fumonisin B₁ (FB₁) (1) and B₂ (FB₂) (2), their hydrolysed analogues HFB₁ (3) and HFB₂ (4) and the recently discovered fumonisin derivatives N-palmitoyl-HFB₁ (5) and N-carboxymethyl-FB₁ (6) were compared for their toxicity in a short term bioassay using brine shrimp (Artemia salina). The brine shrimp were hatched in artificial sea water and exposed to the fumonisins in microwell plates with a mortality endpoint after 48 hours. LC₅₀ values were calculated after Probit transformation of the resulting data. Of the substances tested, fumonisin B₁ emerged to be the most toxic whereas its N-carboxymethyl analogue was 100-fold less effective. The hydrolysed fumonisins showed a four- to sixfold reduced toxicity compared to FB₁. N-Palmitoyl-HFB₁ had a higher LC₅₀ value than its precursor HFB₁. The brine shrimp assay proved to be a convenient and rapid system for toxicity assessment of this group of mycotoxins.     

Perioperatives Management bei Diabetes mellitus

The prevalence of diabetes in hospitalized adults is conservatively estimated at 12–25% and rising. Poor glucose control and presence of diabetes complications (e.g. diabetic nephropathy, diabetic neuropathy, atherosclerosis) are commonly regarded as risk factors for perioperative morbidity and mortality. Thus it is crucial to determine diabetes comorbidities preoperatively in order to avoid perioperative renal and cardiovascular complications. Perioperative glycemic control is challenging due to preoperative changes in diabetes treatment and the effects of surgery-associated stress hyperglycemia. For patients in general surgical units, evidence for specific glycemic goals is based on epidemiologic and physiologic data rather than clinical trials. According to guidelines of the German Society of Nutrition, the approximation of normoglycemia is reasonable as long as hypoglycemia is avoided (suggested range for plasma glucose 80–145 mg/dL).