Subtype IV of the BK polyomavirus is prevalent in East Asia.

BK polyomavirus (BKV) is ubiquitous in human populations, infecting children asymptomatically and then persisting in the kidney. Using either serological or genotyping methods, BKV isolates have been classified into four subtypes (I-IV), with subtype I mainly detected in all countries studied so far. To elucidate the subtype of BKV prevalent in East Asia, we examined BKV-positive urine samples collected from immunocompetent elderly patients in Mongolia, Northeast China, Northwest China, Southeast China, Southwest China, Vietnam and Japan. The 287-bp typing region of the viral genome in each of these samples was PCR-amplified and sequenced, and a phylogenetic tree was constructed. According to the tree, BKV isolates in East Asia were unambiguously classified into subtype I or IV (subtypes II and III were not detected). In Japan, subtype I was mainly detected and subtype IV was rare, whereas in the other regions subtype IV was detected frequently, at rates ranging from 24 to 100%. Thus, East Asia (excluding Japan) is a region in which subtype-IV BKV is prevalent, a finding that requires the view of the geographic distribution of BKV subtypes to be revised. Furthermore, we present evidence that the immunological states of urine donors do not affect the pattern of BKV subtypes.

Unambiguous identification of JC polyomavirus strains transmitted from parents to children.

JC polyomavirus (JCV), the etiological agent of progressive multifocal leukoencephalopathy, is ubiquitous in humans, infecting children asymptomatically, then persisting in renal tissue. It has been proposed that JCV is transmitted mainly from parents to children through long-term cohabitation. The objective of this study was to further elucidate the mode of JCV transmission. In 5 families, we selected parent/child pairs between whom JCV was probably transmitted (judged on the basis of the identity of a 610-bp JCV DNA sequence between the parent and child). We established 5 to 9 complete JCV DNA clones from the urine of each parent or child. The complete sequences of these clones were determined and compared in each family. Nucleotide substitutions were detected in 4 parents and 1 child, and sequence rearrangements (deletions or duplications) were found in 2 parents and 2 children. Phylogenetic comparison of the detected sequences indicated that the diversity of JCV DNA sequences was generated in each family (i.e. not caused by multiple infection). We found that in 4 of the 5 families, a sequence detected in the parent was completely identical to one in the child. These findings provided further support for the proposed mode of JCV transmission, i.e. parent-to-child transmission during cohabitation.

Asian domains of four major genotypes of JC virus, Af2, B1-b, CY and SC.

JC virus (JCV) strains worldwide can be classified into various genotypes based on DNA sequence variations. To define the domains of the four major JCV genotypes in Asia, we collected urine samples at six unstudied sites: three in southeastern Asia, two in the central highlands and one in central Asia. DNA was extracted from urine samples, and used to amplify a 610-bp region of the viral genome. For each geographical site, we determined 16 to 31 sequences, from which a phylogenetic tree was constructed to unambiguously classify detected JCV isolates into distinct genotypes. From JCV genotype profiles at the sites studied here and elsewhere, the following conclusions were drawn. Although Af2 is the major genotype in Africa, this genotype also occurs in western and central Asia. B1-b mainly occurs in western and central Asia, including the central highlands. CY occurs in northeastern Asia with the southern boundary between China and southeast Asian countries. Although SC predominates in southeastern Asia, it also occurs in northern and central Asia at lower frequencies. In addition, a few minor JCV genotypes (B1-a, B2 and B3) occur at many sites. We discuss here the anthropological and medical significance of the present findings.

Expression of the voltage-dependent chloride channel ClC-3 in human nasal tissue.

In the present study, ClC-3, one of the voltage-dependent chloride channels, was identified in human nasal tissue. In situ hybridization and immunohistochemical investigations demonstrated the localization of ClC-3 in the serous acini and ductal portions of submucosal nasal glands, which are the primary source of nasal secretion. Our data suggest that this channel contributes to nasal secretion via chloride transport. Its dysfunction might lead to abnormal nasal secretion in such pathological states as sinusitis.

Presence of Streptococcus infection in extra-oropharyngeal head and neck squamous cell carcinoma and its implication in carcinogenesis.

To investigate the involvement of S. anginosus infection in head and neck cancer in the extra-oropharyngeal cavity, we analyzed 3 DNA samples prepared from squamous cell carcinoma of the external auditory canal and one from squamous cell carcinoma of the skin using polymerase chain reaction (PCR) analysis and Southern blot analysis to detect the DNA sequence of S. anginosus. We also examined these four specimens by Gram's stain to detect the streptococcal bacterial bodies. By PCR analysis, the DNA sequence of S. anginosus was found in 4 out of 4 (100%) DNA samples obtained from these tumors. By Southern blot analysis, positive bands were detected in one out of the 3 (33%) samples from the tumor taken from the external auditory canal. We detected streptococcal bacterial bodies in one of the three specimens from the tumor obtained from cancer of the external auditory canal and in the one specimen from the skin cancer by the method of Gram's stain. Contrary to our expectations, these bacterial bodies were located in the middle of the tumor. Since S. anginosus is thought to exist in the mouth as a normal flora and to be located mainly in the gingiva and dental plaque, these data strongly indicate that S. anginosus infection is implicated in the carcinogenesis of head and neck squamous cell carcinoma.

The expression of apoptosis-related proteins in the aged cochlea of Mongolian gerbils.

OBJECTIVE: Apoptotic changes have been reported in the aged gerbil cochlea and are speculated to be one of the principal causes of presbyacusis. The objective of the study was to determine the underlying mechanism of apoptotic change in the aged gerbil cochlea. STUDY DESIGN: Prospective controlled animal study. METHODS: We examined the tissue distribution of bcl-2, bax, caspase-3p20, and caspase-3p32 using immunohistochemical techniques in the young and aged gerbil cochlea, together with the measurement of the distortion product of otoacoustic emission (DPOAE). RESULTS: Aged gerbils showed a significant reduction of the DPOAE amplitude as compared with that of the young gerbils, suggesting a disturbance of the auditory function in the aged cochlea. There was a significant decrease in the number of bcl-2-positive cells in the aged gerbils. The expression of bax in the aged group was slightly increased but did not significantly differ from that in the young gerbils. A significantly increased number of caspase-3p20-positive cells was observed in the organ of Corti, spiral ganglion, and lateral wall of cochlea in the aged gerbils as compared with those of the young gerbils. There was no significant difference in the expression levels of caspase-3p32 between the young and aged groups. In the aged cochlea, the degree of deterioration of DPOAE responses was compatible with those of both the reduction of bcl-2 and the activation of caspase-3p20. CONCLUSION: These data suggest that the suppression of bcl-2 protein expression may lead to apoptosis-induced presbyacusis through activation of caspase-3 in the aged gerbil cochlea.

Quantitative assessment of the pharyngeal airway by dynamic magnetic resonance imaging in obstructive sleep apnea syndrome.

Dynamic changes in the pharyngeal airway of patients with obstructive sleep apnea syndrome (OSAS) were evaluated by quantitating the findings of real-time imaging performed during wakefulness and spontaneous sleep by means of dynamic magnetic resonance imaging (MRI). Six patients with OSAS and 3 non-OSAS subjects, selected prospectively and randomly, underwent polysomnography and dynamic MRI. The cross-sectional areas of the soft palate and oropharynx and the anterior-posterior airway dimensions seen during wakefulness and spontaneous sleep were calculated by US National Institutes of Health imaging software. On the basis of a case control study, comparisons were made with age-matched and body mass index-matched obese non-OSAS snorers. Spontaneous sleep caused significant obstruction and narrowing of various sites of the pharyngeal airway in the OSAS patients, but not in the non-OSAS subjects. During wakefulness, the non-OSAS subjects showed no marked narrowing of the pharyngeal airways, whereas a transient but significant narrowing was observed in the OSAS patients. The mean values of both the cross-sectional area and the anterior-posterior diameter at the soft palate were significantly reduced by spontaneous sleep in the OSAS patients. Dynamic MRI in awake OSAS patients shows promise as a routine diagnostic tool for localizing the upper airway collapse for appropriate selection of surgical therapy.

Expression of the Sox10 gene during mouse inner ear development.

Mutations in the SOX10 gene, encoding a cell-lineage specific transcription factor, are associated with congenital deafness. We analyzed the expression of Sox10 mRNA in developing mouse inner ear by in situ hybridization. Sox10 mRNA is expressed in the entire epithelia of the otic vesicle at embryonic day 11.5 (E11.5) and in the developing cochlea and vestibule at E13.5. In postnatal day 8 and adult cochleas, Sox10 expression is restricted to the supporting cells of the organ of Corti. These expression profiles suggest that Sox10 is important for development of the cochlea.

Streptococcus anginosus in head and neck squamous cell carcinoma: implication in carcinogenesis.

It has been suggested that Helicobacter pylori (H. pylori) infection might be associated with not only gastric ulcers but also gastric malignancies. Recently, it was reported that the Streptococcus anginosus (S. anginosus) DNA sequence was found in DNA samples extracted from esophageal cancers. Because smoking and alcohol abuse are regarded as risk factors for both esophgeal cancer and head and neck cancer, infection of S. anginosus might be associated with carcinogenesis of head and neck cancer. To investgate the involvement of S. anginosus infection in head and neck cancer, we analyzed 217 DNA samples prepared from head and neck squamous cell carcinomas. We performed PCR analysis with S. anginosus-16S ribosomal DNA-specific primers, and Southern blot analysis. For detection of S. anginosus in the oral and pharyngeal cavities, we used oropharyngeal bacteriological culture and PCR analysis of gingival smears of the patients. By PCR analysis, the S. anginosus DNA sequence was found in 217 out of 217 (100%) DNA samples obtained from head and neck cancers. By Southern blot analysis, positive bands were detected in 41 out of 125 (33%) samples. We could find no S. anginosus colony in oropharyngeal bacteriological culture dishes of 53 patients with and without head and neck cancer. On the other hand, we found the S. anginosus DNA fragment in 8 out of 8 DNA samples obtained from gingival smears by PCR analysis. These data indicate that the upper aerodigestive environment of the patients permitting S. anginosus infection was implicated in the carcinogenesis of head and neck squamous cell carcinoma.

Measurement of stapedius contraction during vocalization effort in patients after laryngectomy or tracheostomy.

The contraction of the stapedius muscle during the effort of vocalization was examined by measurement of acoustic compliance in subjects who had undergone laryngectomy or tracheostomy. No significant level of persistent compliance change was recorded in any of the subjects, indicating the absence of effective contraction of the stapedius during the vocalization effort. In two subjects who use an electrolarynx, although no significant compliance change resulted from the simple vocalization effort without the electrolarynx (no actual vocalized sound), a remarkable level of persistent compliance change was observed during the vocalization using the electrolarynx. These results seem to indicate that a simple vocalization effort without actual voice cannot elicit effective contraction of the middle ear muscles, and that sound generation during vocalization is essential for effective contraction of the middle ear muscles during vocalization, at least in some human subjects.

Apparent change of masking functions with compression-type digital hearing aid.

Signal perception ability under conditions of a narrow band masker in subjects with hearing aids was examined using a theoretical model of the auditory nerve fibre (ANF) with a deteriorated tuning curve in addition to measurements of actual masking function in subjects wearing hearing aids. The results obtained indicate that the apparent masking function could be affected by the frequency-gain character as well as by the degree of compression. Usually, the compression-type of amplification with flat and/or high-frequency weighted characteristics improves not only the apparent thresholds but also the apparent masked thresholds under conditions of lower frequency masking. On the other hand, a low-frequency masker amplified by a higher gain with low-frequency weighted amplification could cause larger upward-masking effects on the signal perception of the higher frequency signal in some conditions. The present study may contribute to our understanding of the underlying mechanisms of the effects of different amplification by the aid.

The time-course of the effects of contralateral sound on the level of distortion product otoacoustic emissions.

The effects of the addition of contralateral noise on the level of distortion product otoacoustic emissions (DPOAEs) were examined. In the present study, the DPOAEs were recorded for a relatively long period (2 minutes), and the time-course of the effects of contralateral sound on the level of DPOAEs were considered. In general, the addition of the contralateral noise resulted in suppression of the level of DPOAEs. The time-course of this suppression appeared to depend on the level of the contralateral noise. When the level of the contralateral noise was low, the suppression of the level of DPOAEs seemed to be largely unchanged for at least 2 minutes. In contrast, when a relatively high level of contralateral noise was used, the suppression of the level of DPOAEs decreased with time.

Identification of carp proopiomelanocortin-related peptides and their effects on phagocytes.

We report the immunomodulating effects of proopiomelanocortin (POMC)-related peptides on phagocytic cells in carp. The complete amino acid sequences of two carp POMCs (I and II) were deduced from the nucleotide sequences after cDNA cloning. Both POMCs consist of 194 amino acids (91% sequence identity) including identical alpha-melanotropin (MSH) and beta-endorphin (EP). All hormonal peptides derived from two POMCs were identified by mass spectrometry after separation by high-performance liquid chromatography of an acid-acetone extract from a single pituitary. These peptides were alpha-MSH, N-Des-Ac-alpha-MSH, di-Ac-alpha-MSH, beta-MSH I, beta-MSH-II, N-Ac-beta-EP(1-29), corticotropin-like intermediate lobe peptide I and II and N-terminal peptide of POMC I and II. The immunomodulating effects of synthetic MSHs and EPs on phagocytic cells from carp head kidney were examined. Di-Ac-alpha-MSH, beta-MSH I, N-Ac-beta-EP(1-29) and beta-EP(1-29) increased the production of superoxide anion at 0.1-100 ng ml-1 for these MSHs and 1-100 ng ml-1 for EPs in RPMI 1640 medium.

Expression of connexin 31 in the developing mouse cochlea.

Connexin 31 (Cx31) mutations cause an autosomal dominant form of high-frequency hearing loss. The immunohistochemical localization of Cx31 in mouse cochlea was studied at different ages between 0 and 60 days after birth (DAB). Cx31-like immunoreactivity was detected in fibrocytes of spiral ligament and spiral limbus at 12 DAB, gradually enhanced with the increase of age and reached the adult pattern on 60 DAB. Immunoreactivity decreased gradually from the basal to apical turn in all developmental stages. The mRNA of Cx31 was also identified by RT-PCR. The distribution of Cx31 and connexin 26 were obviously different in the developing mouse cochlea. The expression and distribution of Cx31 in the development may explain the progressive hearing loss in human Cx31 mutations.

Characterization of novel and identified genes in guinea pig organ of corti.

A number of proteins are expressed in the organ of Corti and are considered to be responsible for hearing. However, most of them have not been identified. Therefore, to achieve a better understanding of the genetic factors influencing these traits, the first step is to characterize the genes expressed in the organ of Corti. In the present study, a cDNA library was constructed from the guinea pig organ of Corti. After sequencing isolated clones, 196 expressed sequence tags (ESTs) were identified with FASTA analysis: 65 ESTs showed significant sequence homology to previously identified genes in guinea pig, human or other species, and 131 ESTs showed no significant matches to sequences already present in the DNA database DDBJ/GenBank/EMBL. A variety of matching sequences, some of which were known to be cochlea-specific, were found through FASTA analysis of the 65 clones. RT-PCR with a panel of 10 different tissue mRNA revealed the restricted expression of 13 unknown clones. The results of our analysis allowed the establishment of a list of genes expressed in the guinea pig organ of Corti.

A case of extramedullary plasmacytoma arising from the nasal septum.

A rare case of extramedullary plasmacytoma arising from the nasal septum with localized amyloid deposition is reported. A 75-year-old woman presented with a history of post-nasal discharge and nasal obstruction for several months. Endonasal endoscopic observation revealed the presence of a mass arising from her nasal septum with an extension to the nasopharynx. No cervical lymph nodes were palpable. The biopsy specimen was diagnosed as a plasmacytoma (IgG, lambda-light chain type). Both serum myeloma-protein and urine Bence-Jones protein were negative. Bone marrow biopsy, a chest radiograph, total body skeletal survey and 67Ga- and 99mTc-scintigrams showed no other systemic lesions. These findings confirmed the diagnosis of extramedullary plasmacytoma in the nasal septum. The patient received irradiation of 40 Gy without clinically detectable reduction of tumour size. The patient eventually underwent complete resection of the tumour by KTP/532 laser under endonasal endoscopic control. Pathologically, the tumour mass was composed mainly of amyloid deposition with a marked reduction of tumour cells. This indicated the radiosensitiveness of tumour cells, which was clinically masked by the increased amyloid deposition. The clinical presentation, pathological features and surgical procedures are described with a review of the literature.

Endonasal endoscopic marsupialization of paranasal sinus mucoceles.

Paranasal sinus mucoceles are relatively common in Japan, especially after prior Caldwell-Luc surgery. Recently developed endonasal endoscopic approaches were used for the drainage and marsupialization of mucoceles. We present the surgical treatment of 97 patients with mucoceles, including 68 maxillary, 13 ethmoid, nine frontal, seven sphenoid, eight frontoethmoid, and one sphenoethmoid sinuses. Six patients with maxillary mucoceles were operated via a sublabial incision. For frontal mucoceles, four patients were treated by a combined external and endonasal endoscopic approach. The other mucoceles underwent complete marsupialization under endonasal endoscopic control. There were no intraoperative or postoperative complications. No evidence of recurrence was observed in any patients during follow-up periods ranging from 36 to 84 months.

Prognostic factors of chronic rhinosinusitis under long-term low-dose macrolide therapy.

We studied the immunological and histopathological factors that affect the prognosis of chronic rhinosinusitis under long-term low-dose macrolide therapy. Sixteen patients with chronic rhinosinusitis were given 200 mg clarithromycin or 150 mg roxithromycin orally once a day without other concurrent treatments for 2-3 months. Measurement of the serum IgE level, blood cell count and differential leukocyte count of the peripheral blood, cytological assessment of the nasal smear and computed tomographic (CT) scans of the paranasal sinuses were performed before treatment. The opacity of the sinuses was estimated and scored by the CT images. After treatment, anterior ethmoidal mucosa samples were collected, an infiltrated inflammatory cells, interferon (IFN)-gamma-positive cells and interleukin (IL)-4-positive cells were examined histologically and immunohistochemically. The severity of nasal symptoms was scored before and after treatment, and the improvement rate of the score (symptomatic improvement rate) was calculated. Patients with normal levels of serum IgE (