Use of a Test Diet in Screening for Neuroblastoma Reduces False-Positives Attributable to Food Intake

ABSTRACT. We attempted to reduce false-positives during screening for neuroblastoma using a qualitative urine test by introducing a test diet without foodstuffs known to cause false-positive results. In preliminary in-vivo experiments, intake of contra-indicated foods such as orange juice or banana was shown to result in high percentages of false-positive results several hours after food intake. False-positive results were obtained even after 24 hours among breast-fed infants whose mothers received orange juice. In a controlled field trial the false-positive rate was reduced to 2.84% among 540 infants taking the test diet compared with 5.05% among 9844 control infants following conventional guidance on contra-indicated foods (p < 0.05). For comparison, a questionnaire survey of nationwide screening in Japan in 1987 revealed that 66% of the screening centres employed qualitative urine tests, either a Spot or Dip method. False-positive rates, including those due to inappropriate urine collection, ranged from 0.4 % to 33.7% (mean 7.1%). Rates ranged from 0.2% to 18.7% (mean 3.4%) in the remaining 34% of screening centres employing a quantitative method with high performance liquid chromatography.     

Serum Level of Interleukin-4 in Patients with Perennial Allergic Rhinitis During Allergen-Specific Immunotherapy

Interleukin-4 (IL-4) may play a central role in the IgE synthesis system, the development of Th-2-like cells, and co-ordination as well as the persistence of airway inflammatory process in allergic disorders. Therefore, IL-4 plays a key role in airway allergic disorders. This study aimed at investigating the serum concentrations of IL-4 in patients with perennial allergic rhinitis, with special reference to the possible changes and the clinical relevance following long-term immunotherapy. The study has demonstrated that the serum level of IL-4 in allergic rhinitis patients before immunotherapy is significantly higher than that in non-atopic individuals. However, the serum IL-4 level in allergic rhinitis patients did not decrease following anti-allergic medications but significantly decreased following immunotherapy. The percentage decrease in IL-4 was correlated significantly with the percentage decrease in specific IgE antibodies following long-term immunotherapy. Immunotherapy also significantly decreased specific IgE antibodies, but this reduction in specific IgE antibodies was not significantly correlated with the clinical improvement. In contrast, the percentage decrease in serum IL-4 was significantly correlated with the percentage decrease in symptomatic scores. The authors interpret these data to mean that immunotherapy alters T-cell cytokine profiles in the long-term, and a decline of IL-4 following immunotherapy could modulate not only production of specific IgE antibodies but also inflammatory cellular events, leading to symptomatic relief in allergic rhinitis.     

Interaction of lipophilic peptides derived from mastoparan with phospholipid vesicles

Various kinds of lipophilic peptides were prepared by acylation of an ct-helical peptide, mastoparan, to investigate the effects of acyl groups on the interaction of peptides with phospholipid membranes. α-Helicity of the peptides was increased by introduction of long acyl groups. Acyl peptides showed different membrane-perturbation activities for neutral and acidic phospholipid vesicles, whereas a peptide with a dialkycarbamoyl group always exhibited a strong activity. High hemolytic activities were observed for the peptides with long acyls (single or double chain). These results indicate that lipophilic groups introduced to mastoparan contribute greatly to the interaction of the peptide with phospholipid membranes with lengthening of the acyl chain and that the structural character of the lipophilic group also influences the conformation of the peptide.     

Antibodies to hepatitis C virus and elevated transaminase levels in a town of hyperendemicity in Iwate, Japan

In an annual survey for liver function tests in persons aged > xs35 years in Iwate Prefecture, Japan, a town was identified where high levels of alanine aminotransferase abounded. Of 5152 inhabitants aged > 35 years in this town, antibodies to hepatitis C virus (HCV) determined by enzyme-linked immunosorbent assay with HCV core peptides were detected in 798 (15.5%) people, hepatitis B surface antigen was detected in 47 (0.9%) people and antibodies to hepatitis B surface antigen and/or hepatitis B core antigen unaccompanied by surface antigenaemia were detected in 1748 (33.9%) people. Antibodies to HCV core peptides correlated closely with the antibodies detected by passive haem-agglutination with recombinant HCV proteins of the second generation. Antibodies to HCV core peptides were particularly common in one of the nine districts of the town (district 8), where 276 (45.3%) of 609 inhabitants tested positive; there were no differences in the frequency of serological markers of hepatitis B virus (HEV) infection among residents in the nine districts. Of the 798 individuals with antibodies to HCV core peptides, 257 (32.2%) were found to have elevated transaminase levels. A history of transfusion was associated with a high frequency of antibodies to HCV core peptides, except in district 8 where such antibodies were equally frequent in residents irrespective of transfusions. These results indicate an epidemiology of HCV distinct from that of HBV in this town and a very local spread of HCV, as well as a high frequency of hepatic injuries in individuals with antibodies to HCV.     

STRUCTURAL STUDIES ON STEM BROMELAIN

Stem bromelain was cleaved with cyanogen bromide, and the products were fractionated with and without prior maleylation and sulfitolysis. The fragments that corresponded to the carboxyl-terminal half of the molecule were isolated and nearly completely sequenced. This portion of the enzyme molecule contained one disulfide linkage. A specific cleavage at the amino peptide bonds of that cystine residue by reduction, modification into S-cyano derivatives and exposure to alkali gave important information of the amino terminal sequence. By combining the present data with the previously known partial sequence of the parent molecule, 101 amino acid residues were aligned down to the carboxyl terminus and compared with those of papain. The sequence homology between carboxyl-terminal halves of these two thiol proteases of plant origin was found to be 34.7%.     

Erythema nodosum-like eruption in sarcoidosis

Two cases of sarcoidosis with tender, erythematous nodules on the legs are reported. The cutaneous lesions were clinically similar to those of erythema nodosum, but histologically showed non-caseating epithelioid granulomas. A review of 14 cases of this particular sarcoid eruption reported in Japan showed that 13 had ocular involvement as in our cases. In the light of the high frequency of ocular involvement, a skin biopsy should be considered in patients presenting with erythema nodosum-like eruptions situated on the legs.     

Demonstration of Somatostatin Production in Medullary Carcinoma of the Thyroid

The localization and release of somatostatin in seven casesof medullary carcinoma of the thyroid were investigated by meansof specific anti-somatostatin antibody. In all four patientsexamined high concentrations of plasma somatostatin (125–400pg/ml) and calcitonin (1,917–82,000 pg/ml) were shown.Primary and metastatic tumor tissues obtained from three patientscontained higher amounts of somatostatin (13.1–350.0 ng/gwet wt) than the surrounding tissues. Immunohistochemically,somatostatin-immuno-reactive (IR) cells and calcitonin-IR cellswere shown to compose the majority of tumor cells, leaving asmall number of nonreactive cells in primary and metastatictumors of the seven cases, but in general calcitonin-IR cellswere more numerous than somatostatin-IR cells. The numbers ofcalcitonin-IR and somatostatin-IR cells were not markedly differentfrom case to case, but their population density did not alwayscorrespond to the concentrations of plasma and tissue somatostatin.These data indicate that medullary carcinoma of the thyroidis one of the somatostatin-producing tumors.