Identification of tissue-embedded ascarid larvae by ribosomal DNA sequencing

Polymerase chain reaction (PCR) was applied to identify tissue-embedded ascarid nematode larvae. Two sequences of the internal transcribed spacer (ITS) regions of ribosomal DNA (rDNA), ITS1 and ITS2, of the ascarid parasites were amplified and compared with those of ascarid-nematodes registered in a DNA database (GenBank). The ITS sequences of the PCR products obtained from the ascarid parasite specimen in our laboratory were compatible with those of registered adult Ascaris and Toxocara parasites. PCR amplification of the ITS regions was sensitive enough to detect a single larva of Ascaris suum mixed with porcine liver tissue. Using this method, ascarid larvae embedded in the liver of a naturally infected turkey were identified as Toxocara canis. These results suggest that even a single larva embedded in tissues from patients with larva migrans could be identified by sequencing the ITS regions.     

Immune responses of interferon gamma (IFN-gamma) knock out mice to repeated Haemaphysalis longicornis (Acari: Ixodidae) nymph infestations

To investigate the immunological mechanisms of acquired resistance to tick infestation, interferon gamma (IFN-gamma) deficient mice (IFN-gamma mice) were used to assess interleukin-4 (IL-4) and antibody production levels against tick salivary gland antigen on three successive infestations with Haemoaphysalis longicornis Neumann nymphs. The engorged body weight of the ticks decreased during the second and third infestations. Similar observations were noted in IFN-gamma+/+ mice. However, the engorged body weight of the ticks from IFN-gamma +/+ mice were considerably lower than those from IFN-gamma-/- mice. A marked increase in antibody production during the second and third infestations was observed indicating that IFN-gamma-/- mice could acquire immunological resistance against H. longicornis nymphs. Moreover, IL-4 levels were higher during the first and third infestations but decreased during the second infestation. IL-4 levels were significantly higher in IFN-gamma-/- mice than in IFN-gamma+/+ mice. We have shown here that the statistically significant high IL-4 levels observed in IFN-gamma-/- mice may be a result of type 2 helper cell (Th2) polarization. However, the apparently higher IL-4 levels during the first and third infestations and the notable decline during the second infestation suggest that other cytokines or factors in the host immune system may play a part in regulating IL-4 levels.     

An analysis of the relationship between aggressiveness and personality traits of children

The purpose of the present study was to understand the concept of aggressiveness of children through an analysis of the relationship between aggressiveness and personality traits. A total of 1,206 elementary school children were enrolled in the study. In order to investigate the correlation, a path analysis was performed using multiple regression analyses in which 4 variables of aggressiveness (irritability, hostility, physical aggression and verbal aggression) were employed as dependent variables and 5 variables of personality traits (agreeableness, conscientiousness, emotionality, openness and extroversion) were used as independent variables. The results of the analysis indicated that significantly positivepath was observed from extroversion to all four variables of aggressiveness. Extroversion indicated especially strong influence on irritability and physical aggression. A significantly negativepath was observed from agreeableness to irritability and hostility. From conscientiousness, a negative path was observed towards physical aggression and a positive path towards verbal aggression. A significantly negative path was observed from emotionality only towards verbal aggression. It was assumed that each of the four inferior characteristics of aggressiveness of children had a complex nature to be influenced by multiple personality traits.     

Frequent occurrence of in vivo clonal expansion of CD4− CD8− T cells bearing T cell receptor αβ chains in adult humans

We have previously reported 2 cases of healthy men showing in vivo monoclonal expansion of mature CD4^? CD8^? αβ T cells. In the present study, an additional 3 adults were found to exhibit such an expansion, among a total 464 adult donors studied. These 5 individuals were otherwise physiologically normal, with no history of severe illness and autoimmune disease at the time of examination. To investigate the mechanisms of the clonal expansion, further characterization of the clonal cells was attempted. No apparent preference for usage of the Tcell receptor β chain variable region was observed in the clonal T cells. These clonal T cells showed lectin-dependent or redirected antibody-dependent cell-mediated cytotoxicities, whereas they could not lyse autologous lymphoblastoid cell lines. Failure of Fas antigen expression was not observed for any of these clones. These results suggest that clonal expansion of CD4^? CD8^? αβ T cells frequently occurs in the periphery without any T cell abnormalities.     

Peripheral T-cell Lymphomas Immunologic and Enzyme Histochemical Analysis of 15 Cases

Ffteen cases of peripheral T cell lymphoma were studied to evaluate the respective properties of various histologic types using enzyme histochemical and ultrastructural examinations in addition to immunological methods. Eleven cases in an ATLA negative group manifested various histologic patterns such as IBL like, pleomorphic and Lennert's lymphomas in comparison with the relatively monomorphic proliferation of neoplastic lymphoid cells in the 4 ATLA positive cases. The presence of neoplastic clear cells is characteristic of peripheral T-cell malignancies, and is likely to be found in CD4 lymphomas. There is an occasional reaction of epithelioid histiocytes and plasma cells with eosinophils, the former being designated Lennert's lymphoma and the latter IBL like T-cell lymphoma. Immunological examination revealed four immunophenotypic patterns: (1) CD2⁺3⁺4⁺8⁺, (2) CD2⁺ 3⁻4⁺8⁻, (3) CD2⁺3⁺4⁻8⁺, and (4) CD2⁺3⁺4⁺8⁺, but did not provide information concerning the intimate relationship between histologic types and immuno phenotyes. β-Glucuronidase reactivity, however, contributed to the distinction between helper and suppressor T cell malignancies, suggesting its usefulness for distinguishing these two cell types and their malignant counterparts.     

In vitro early changes in intercellular junctions by treatment with a chemical carcinogen

To examine early intercellular junction changes caused by treatmentwith 9, 10-dimethyl-l, 2-benzanthracene (DMBA), rat lingualepithelium was cultivated in isolation and observed by electrophysiological,freeze-fracture and whole-mount electron microscopy. Electrophysiologicalmeasurements showed a transient decrease in membrane potentialof -10.2 mV 6 h after the treatment. It returned to almost thesame level as that of the control group 1 day later. Six hoursafter treatment, input resistance decreased rapidly to 5.3 Mbut increased to 18.0 M 12 h after treatment. Transient reductionof input resistance and membrane potential occurred prior tothe decrease in the coupling ratio 6 h after treatment withDMBA. In freeze-fracture replicas, the number of gap junctionsdecreased by 45% of the control value 6 h after treatment withDMBA. At 12 h and thereafter, the number and area of gap junctionssubsequently decreased by 60–80% of the control value.Alterations in the number and area of desmosomes were similarto those of the gap junctions. The formation of epithelial cytoskeletons,partially devoid of the 2–4 and 5–8 nm filamentswas also observed. A decrease in the density of filament networksbeneath the plasma membranes was especially apparent. Treatmentwith a carcinogen brought about morphological cellular changesas early as 6 h after treatment, and such early changes mighttrigger metabolic cellular abnormalities. Affected cells appearto move away from normal cells in a process of repeated destructionand revision of intercellular junctions, and cytoskeletons.     

Ingestion of High β-Glucan Barley Flour Enhances the Intestinal Immune System of Diet-Induced Obese Mice by Prebiotic Effects

The prebiotic effect of high β-glucan barley (HGB) flour on the innate immune system of high-fat model mice was investigated. C57BL/6J male mice were fed a high-fat diet supplemented with HGB flour for 90 days. Secretory immunoglobulin A (sIgA) in the cecum and serum were analyzed by enzyme-linked immunosorbent assays (ELISA). Real-time PCR was used to determine mRNA expression levels of pro- and anti-inflammatory cytokines such as interleukin (IL)-10 and IL-6 in the ileum as well as the composition of the microbiota in the cecum. Concentrations of short-chain fatty acids (SCFAs) and organic acids were analyzed by GC/MS. Concentrations of sIgA in the cecum and serum were increased in the HGB group compared to the control. Gene expression levels of IL-10 and polymeric immunoglobulin receptor (pIgR) significantly increased in the HGB group. HGB intake increased the bacterial count of microbiota, such as Bifidobacterium and Lactobacillus. Concentrations of propionate and lactate in the cecum were increased in the HGB group, and a positive correlation was found between these organic acids and the IL-10 expression level. Our findings showed that HGB flour enhanced immune function such as IgA secretion and IL-10 expression, even when the immune system was deteriorated by a high-fat diet. Moreover, we found that HGB flour modulated the gut microbiota, which increased the concentration of SCFAs, thereby stimulating the immune system.     

Photoreceptor differentiation of retinoblastoma: An electron microscopic study of 29 retinoblastomas

Retinoblastomas exhibit a unique form of differentiation to produce cell elements similar to those seen in a photoreceptor cell. An ultrastructural study was performed on 29 cases of retinoblastoma to further clarify the cytologic characteristics of the tumor cells. The age of the retinoblastomas averaged 17.1 months and the tumor cells showing photo-receptor differentiation were demonstrated in 10 cases (35%). The findings were especially notable in retinoblastomas with Flexner-Wintersteiner rosette formation (seven cases, 28%). Similar photoreceptor differentiation was also evident in solid cell clusters without rosette formation (four cases, 14%). The presence of photoreceptor elements was assumed to be significantly frequent both in Flexner-Wintersteiner rosettes and in the solid cell clusters. The cell cytoplasm also showed proliferation of long mitochondria and microtubules, reflecting photoreceptor differentiation. The hereditary-type retinoblastoma showed more advanced cell differentiation than the non-hereditary type. Photoreceptor differentiated retinoblastoma showed rather indolent growth compared with the undifferentiated type, and the former can expect a curative treatment by operation. These observations provide additional findings of the biological nature of retinoblastomas.     

Prenatal exposure to ionizing radiation and subsequent development of seizures

Seizures are a frequent sequela of impaired brain development and can be expected to affect more children with radiation-related brain damage than children without such damage. This report deals with the incidence and type of seizures among survivors prenatally exposed to the atomic bombing of Hiroshima and Nagasaki, and their association with specific stages of prenatal development at the time of irradiation. Fetal radiation dose was assumed to be equal to the dose to the maternal uterus. Seizures here include all references in the clinical record to "seizure," "epilepsy," or "convulsion." Histories of seizures were obtained at biennial routine clinical examinations starting at about the age of 2 years. These clinical records were used to classify seizures as febrile or unprovoked (without precipitating cause). No seizures were ascertained among subjects exposed 0-7 weeks after fertilization at doses higher than 0.10 Gy. The incidence of seizures was highest with irradiation at the eighth through the 15th week after fertilization among subjects with doses exceeding 0.10 Gy and was linearly related to the level of fetal exposure. This obtains for all seizures without regard to the presence of fever or precipitating causes, and for unprovoked seizures. When the 22 cases of severe mental retardation were excluded, the increase in seizures was only suggestively significant and only for unprovoked seizures. After exposure at later stages of development, there was no increase in recorded seizures.     

Extensive metabolism of the flavonoid chrysin by human Caco-2 and Hep G2 cells

1. Chrysin is one of many bioflavonoids with chemopreventive properties in cardiovascular disease and cancer. In an effort better to understand factors that may affect the oral bioavailability of the bioflavonoids from dietary sources, the metabolism of chrysin by cultured intestinal Caco-2 cells and hepatic Hep G2 cells was studied, together modelling human presystemic metabolism. 2. At concentrations that may be achieved in the diet, chrysin was extensively metabolized to two conjugated metabolites, M1 and M2, with no CYP-mediated oxidation. M1 was identified as a glucuronide, and M2 as a sulphate conjugate by LC/MS and other spectroscopic and biochemical techniques. Sulphate conjugation occurred at a rate twice that of glucuronic acid conjugation in both cell types. 3. M1 was catalyzed by UGT1A6 with a Km = 12 microM. M2 was catalyzed both by M- and P-form phenolsulphotransferases (SULT 1A3 and SULT 1A1) with very low Km of 3.1 and 0.05 microM respectively. 4. Pretreatment with 3-methylcholanthrene, interestingly, did not result in oxidation of chrysin but rather in increased glucuronidation. 5. Also, M1 and M2 were the only metabolites formed from chrysin in fresh rat hepatocytes. The metabolism of another flavonoid, apigenin, was very similar to that of chrysin. 6. These observations suggest that both sulphation and glucuronidation are critical determinants of the oral bioavailability of bioflavonoids in humans, although a contribution from CYP-mediated oxidation can not be excluded.