The odontoblast as a sensory receptor cell? The expression of TRPV1 (VR-1) channels

Previous reports have shown the expression of several mechanosensitive ionic channels on the plasma membrane in odontoblasts, which are the cells responsible for dentin formation. The membrane characteristics of odontoblasts imply that they could play critical roles in the mechano-transduction of fluid displacement within dentinal tubules into the electrical cell signals, to carry dentin sensation to the central nervous system. However, the direct ionic mechanism underlying such a dentin nociceptive function remains unclear. In the present study, we investigated the expression of the transient receptor potential vanilloid subfamily member 1 (TRPV1) channel - which essentially contributes to the detection of pain sensation - in rat odontoblasts by immunohistochemical and nystatin perforated patch-clamp techniques. Immunohistochemical observation showed the localization of TRPV1-immunoreactions on the distal regions of odontoblast membranes. In the patch-clamp experiments, we observed capsaicin-induced inward currents that were inhibited by capsazepine, a TRPV1 channel antagonist. Our results indicate a significant expression of TRPV1 channels in odontoblasts, suggesting that odontoblasts may directly respond to noxious stimuli such as a thermal-heat stimulus, and point to the necessity for a reconsideration of the cellular mechanisms of dentin sensation based on the transmembrane ionic signals in odontoblasts.     

Relationship between ABO histo-blood group type and an outbreak of norovirus gastroenteritis among primary and junior high school students: results of questionnaire-based study

Noroviruses are common causative agents of epidemic gastroenteritis in humans. Recent studies showed that human susceptibility to noroviruses was associated with ABO histo-blood group type. It was also observed that various degrees of susceptibility were exhibited by different norovirus strains. In January 2003, an outbreak of acute gastroenteritis including 661 affected primary and junior high school students occurred through lunch bread contaminated with norovirus in Hokkaido, Japan. To clarify the relationship between ABO histo-blood group type and the norovirus infection, we performed a written questionnaire to schoolchildren about the consumption of the bread, onset of symptoms and person-to-person transmission in their household. Questionnaires were returned from 722 schoolchildren (response rate, 65.8%), of whom 55.3% suffered gastroenteritis. As a result of this survey, it was found that schoolchildren with blood group type A (71.1%, 133/187) were more susceptible to the norovirus infection, whereas, schoolchildren with blood group type AB (55.3%, 26/47) were less affected (P (Z0) < 0.025). In addition, the presumptive prevalence rate of person-to-person transmission in each household indicated that schoolchildren with blood group type AB (19.2%, 5/26) had a lower risk of infection than those with blood group type A or O [A : 41.4%, 55/133 O : 39.5%, 49/124 (unknown for one case) ] [P (Z0) < 0.025]. Our findings suggested that persons with blood group type AB were less affected by the norovirus infection in this outbreak.     

Molecular analysis of streptococcal pyrogenic exotoxin genes among group A Streptococcus isolates from Japanese patients with pharyngitis and skin infections

Group A Streptococci (GAS) from patients with pharyngitis and skin infections were examined for T serotypes, emm types, and streptococcal pyrogenic exotoxin gene types. The results were summarized as follows: 1) T and emm types were determined in 130 GAS isolates obtained between 2000 and 2004. Among 85 throat isolates, predominant T/emm types were T12/emm12 (25%), T4/emm4 (19%), and T1/emm1 (14%). Among 45 skin isolates, predominant T/emm types were T28/emm28 (13%), TB 3264/emm89 (13%), Tnontypeable/emm58 (13%), T1/emm1 (11%), and T12/emm12 (11%). Predominant T/emm types of skin isolates in 2000-2004 slightly differed from those during 1990s in our previous report. 2) The presence of streptococcal pyrogenic exotoxin genes in 292 GAS isolates obtained between 1990 and 2004 was examined. Significantly lower proportion of skin isolates, compared with throat isolates, was found to harbor the speA gene (12 versus 26%, respectively; p<0.01), or the speC gene (40 versus 65%, respectively; P<0.01). All but one of tested isolates carried the speB gene. The speB-negative isolate was identified as S. dysgalactiae subsp. equisimilis with the group A antigen. 3) Types of the speA alleles were determined in 59 speA-positive GAS isolates. Among 44 throat isolates, 37 (84%) were speA lineage I (speA1-speA2-speA3-speA6), and 7 (16%) were lineage II (speA4-speA5). Among 15 skin isolates, 11 (73%) were lineage I and 4 (27%) were lineage II. The pairwise associations were observed between emm type and speA allele: emm1 and speA2, emm3 and speA3, emm6 and speA4, emm11 and speA2, emm18 and speA1.     

Increased expression of EGFR and TGF-α in segmental renal dysplasia in duplex kidney

Renal dysplasia (RD) is a disorganised development of renal parenchyma that results in a deficit of functional renal tissue. It is known that the epidermal growth factor (EGF) and the transforming growth factor- (TGF-) enhance renal cell proliferation, migration and differentiation during kidney development through binding to the same EGF receptor (EGFR). The aim of the study was to analyse the expression of TGF- and EGFR in the dysplastic kidney. The specimens of dysplstic upper poles duplex kidneys were surgically resected from 19 patients. Indirect immunohistochemistry was performed using the ABC method employing antibodies against EGFR and TGF-, and gene expression using primers specific to the human genes. There was absent or weak EGFR and TGF- immunoreactivity in normal kidney tissue. In dysplastic kidneys, there was strong TGF- and EGFR immunoreactivity in the epithelium of primitive tubules and strong EGFR immunoreactivity in the connective tissue around the primitive tubules. Our findings of markedly increased local expression of EGFR and TGF- in primitive tubules suggest that EGFR and TGF- may play an important role in altering renal morphogenesis resulting in renal dysplasia.     

Upregulated expression of EGF and TGF-α in the proximal respiratory epithelium in the human hypoplastic lung in congenital diaphragmatic hernia

Newborn infants with congenital diaphragmatic hernia (CDH) still have a high mortality rate. Epidermal growth factor (EGF) and transforming growth factor- (TGF-) are peptide growth factors involved in the fetal lung growth and development. The EGF and TGF- have been reported to promote pulmonary branching activity and alveolar type-II pneumocyte proliferation. Epidermal growth factor and TGF- immunoreactivity and mRNA expression in the bronchial and bronchiolar epithelium is maximal during early fetal life and barely detectable in the proximal airways of neonatal lung. The purpose of this study was to determine protein and gene expression of EGF and TGF- in CDH lung in order to elucidate the potential role of these growth factors in the pathogenesis of pulmonary hypoplasia in CDH. Lung tissue specimens were obtained from archival lung tissue from 11 patients with CDH and 5 controls. Indirect immunohistochemistry was performed using ABC method with anti-EGF and anti-TGF- antibodies. In situ hybridization was performed using EGF and TGF- specific digoxigenin-labeled oligonucleotide probes. The most striking difference between hypoplastic CDH lung and control lung was the strong EGF and TGF- mRNA expression and immunoreactivity in the bronchial and bronchiolar epithelium in CDH lung. The upregulated protein and gene expression of EGF and TGF- in the proximal airways in the CDH hypoplastic lung suggests persistence of fetal stage of pulmonary airway development in CDH.     

A case of squamous metaplasia of the ureter

This paper reports a 73-year-old man who developed ureteral squamous metaplasia. Preoperative drip infusion pyelography showed a ureteral tumor with a major axis measuring 2.5 cm, which had a smooth surface and a broad base. Computed tomography findings suggested that the lesion might be a submucous mesodermal tumor or inverted papillary transitional cell carcinoma. Therefore, retroperitoneal laparoscopic left nephroureterectomy was performed.     

Measuring workplace climate: reliability and validity of the 12-item Organizational Climate Scale (OCS-12)]

In order to investigate the reliability and validity of the short version of the 30-item Organizational Climate Scale (OCS-30; Toshima and Matsuda, 1992, 1995), a self-administered questionnaire was conducted in a sample of 819 employees of two medium-sized private companies in Japan by using the OCS-30, the Generic Job Stress Questionnaire (GJSQ), and the 12-item General Health Questionnaire (GHQ-12). The OCS has two subscales, i.e., the Tradition Scale (TS) and the Organizational Environment Scale (OES). The organizational climate perceived by each worker can be grouped into four categories based on the subscale scores: low TS and high OES (Active), high TS and high OES (Governed), low TS and low OES (Disorganized), and high TS and low OES (Reluctant). Principal component analysis for the OCS-30 was submitted (varimax rotation, the number of factors = 2), and 6 items for each factor, with factor loadings greater than 0.50, were selected for the short version, which constituted the 12-item Organizational Climate Scale (OCS-12). Cronbach's alpha reliability coefficients of the two subscales of the OCS-12 were acceptable; 0.63 for the TS and 0.71 for the OES. Both two subscales of the OCS-12 were significantly correlated with the GHQ-12 and many subscales of the GJSQ, which indicated the good constructive validity of the OCS-12. Among 4 types of organizational climate categorized by the OCS-12, the "Active" group showed the lowest job stress scores. It is suggested that the OCS-12 could be a reliable and valid instrument for assessing workers' perception of workplace climate.