Altered cochlear fibrocytes in a mouse model of DFN3 nonsyndromic deafness

DFN3, an X chromosome-linked nonsyndromic mixed deafness, is caused by mutations in the BRN-4 gene, which encodes a POU transcription factor. Brn-4-deficient mice were created and found to exhibit profound deafness. No gross morphological changes were observed in the conductive ossicles or cochlea, although there was a dramatic reduction in endocochlear potential. Electron microscopy revealed severe ultrastructural alterations in cochlear spiral ligament fibrocytes. The findings suggest that these fibrocytes, which are mesenchymal in origin and for which a role in potassium ion homeostasis has been postulated, may play a critical role in auditory function.

Long-term follow-up study of posterior lumbar interbody fusion

To see whether degenerative changes of the adjacent disks are accelerated by fixation of a lumbar segment, 48 patients who had undergone posterior lumbar interbody fusion (PLIF) more than 5 years previously were investigated radiographically and clinically. Narrowing of disk spaces was observed in 31% of the subjects, but it usually occurred at levels proximal to the fusion. The incidence of adjacent disk narrowing was not significantly higher after PLIF, compared with reports on degenerative changes of lumbar disks with aging. Some subjects showed narrowing of disks that were not adjacent to the fused level, suggesting that individual predisposition played a role in disk narrowing. Instability was not seen in any of the subjects. New development or elongation of the traction spurs at adjacent segments occurred at the disks proximal to the fusion. The clinical results were generally satisfactory, despite progression of degenerative changes on radiographs.

Raman spectroscopic study of changes in fish actomyosin during setting

Actomyosins (AMs) isolated from tilapia, lemon sole, ling cod, and rock fish were heated at 40 degrees C, and structural changes in AMs were investigated using Raman spectroscopy to elucidate low-temperature gelling phenomenon, that is, "setting", of surimi. The following conformational transitions were observed in lemon sole, ling cod, and rock fish gels during setting: a slow unfolding of alpha-helix and exposure of hydrophobic amino acid residues occurring in long-time incubation at 40 degrees C, thereby forming hydrophobic interactions among AM molecules. In addition, the most frequent conformation in disulfide bonds was gauche-gauche-trans (g-g-t) form in the set gel. On the other hand, tilapia AM did not form a gel with heating at 40 degrees C, its alpha-helical structure in the myosin being far more stable than that of the other species. The heat resistance of the tight alpha-helix may prevent the gelation of tilapia AM. It is, therefore, likely that the unfolding of the alpha-helix of myosin is a prerequisite for gelation of AM during setting.

Apoptosis-inducing activity and growth suppression by vesnarinone on human glioma transplanted in nude mice

The growth and morphological change of human glioma transplanted subcutaneously and intracerebrally to nude mice with orally administered vesnarinone, 3,4-dihydro-6-[4-(3,4-dimethoxy-benzoyl)-1-piperazinyl]-2(1H)-quinolinon e, were examined. The tumor volume of human glioma xenograft, GL-9, subcutaneously transplanted to nude mice, was significantly decreased by orally administered vesnarinone at a dose of 500 mg kg-1. Vesnarinone also significantly prolonged the survival of nude mice transplanted intracerebrally with GL-9. Apoptosis was observed in paraffin sections of both subcutaneous and intracerebral GL-9 by the method of direct immunoperoxidase detection of digoxigenin-dUTP-labeled nick ends introduced by terminal deoxynucleotidyl transferase. These findings suggest that vesnarinone suppresses the growth and induces apoptosis of glioma cells in vivo.

Intracellular Ca2+ responses to nucleotides, peptides, amines, amino acids and prostaglandins in cultured pituicytes from adult rat neurohypophysis

The present study aimed to investigate the reactivity of cultured pituicytes from adult neurohypophysis to various bioactive substances using Ca2+ indicator dye Fura-2. A transient increase of intracellular Ca2+ [Ca2+]i was observed when pituicytes were treated with nucleotides (ATP, ADP, UTP, and UDP) and amines (5-HT2 and alpha2-agonist). Treatment with peptides such as endothelin-1 (ET-1), endothelin-3 (ET-3), bradykinin (BK), vasopressin (AVP), and angiotensin II (Ang II) also induced [Ca2+]i increase in pituicytes. Prostaglandin E2 (PGE2) and F2alpha (PGF2alpha) increased [Ca2+]i, but amino acids of GABA, glutamate (Glu), and taurine had no effect. Serum-free culture condition augmented [Ca2+]i responses to ATP, Ang II and 5-HT within 24 h. These results indicate that pituicytes express many of receptors for neurotransmitters or neuromodulators.

Attenuation of urinary sodium excretion during cold-air exposure in trained athletes

To clarify whether an increase in urinary sodium (Na) excretion during cold-air exposure is attenuated in trained athletes, we analyzed the urinary and hormonal responses to cold-air exposure at 15 degrees C in trained (TR, n = 9) and untrained men (UT, n = 9). During 15 degrees C exposure in the UT group, the urinary Na excretion (UNaV), fractional excretion of Na and urinary Na to K ratio (UNa/K) increased significantly (p<0.01-0.05), but there were no variations in creatinine clearance or the filtered Na load. In the TR group, however, no significant changes were demonstrated in these parameters. The amount of increase in plasma noradrenaline and of decrease in plasma volume were greater, and the ADH and adrenaline responses were smaller in the TR group than those found in the UT group during 15 degrees C air exposure. A significant positive correlation was demonstrated between the increase of UNaV and both the relative changes of UNa/K and mean blood pressure. These results indicated that natriuresis during cold-air exposure was induced by the decrease in tubular reabsorption of Na, and that natriuresis was attenuated in trained athletes.

Morphological plasticity and rearrangement of cytoskeletons in pituicytes cultured from adult rat neurohypophysis

The adult rat neurohypophysis reveals drastic morphological plasticity of neuron-glial organization during chronic physiological stimulation. Pituicytes are modified astrocytes in the neurohypophysis, and shape conversion of them largely contributes to the morphological plasticity. The present study aimed to investigate the receptor-mediated mechanism for shape conversion of the pituicyte morphology, particularly in relation with changes of cytoskeletal organization. The cultured pituicytes from adult rat neurohypophysis were mostly flat amorphous shape in normal salt solution. Histochemical experiments showed that thick bundle of microfilament (stress fibers) and fine fibers of microtubule distributed evenly within the pituicyte. When pituicytes were treated with adenosine (more than 1 microM), isoproterenol (IPR); beta-agonist, more than 10 nM), and dibutyryl cyclic AMP (dBcAMP, 1 mM), the pituicyte morphology changed from flat to stellate shape. Upon treatment with dBcAMP, stress fibers within pituicyte cytoplasm disappeared, and microtubule assembled in the cellular processes and cytoplasm surrounding the nucleus. Pretreatment with colchicine (microtubule-disrupting agent, 25 microM) and orthovanadate (tyrosine phosphatase inhibitor, 1 mM) prevented dBcAMP-induced stellation of the pituicyte morphology. Treatment with sphingosine (protein kinase C inhibitor, 10 microM), W-7 (calmodulin dependent protein kinase inhibitor, 40 microM), ML-9 (myosin light chain kinase inhibitor, 20 microM), and cytochalasinB (CytB; microfilament disrupting agent, 5 microM), induced stellation of the pituicyte morphology. Treatment of endothelin-1 (more than 0.1 nM) and endotheline-3 (more than 0.1 nM) reverted dBcAMP-induced stellation of the pituicyte morphology to original flat one and also reverted arrangement of cytoskeletons of stress fiber and microtubules as seen in control one. The present results reveal that pituicyte shape conversion is mediated via beta-adrenergic, adenosine and endotheline and depend on rearrangement of stress fibers and microtubules. In addition, the mechanism of shape conversion of pituicytes cultured from adult neurohypophysis is quite similar to that of astrocytes cultured from neonatal brains and possibly is useful for understanding morphological plasticity of adult brains.

Macromolecular antimicrobial glycoprotein, achacin, expressed in a methylotrophic yeast Pichia pastoris

A cDNA encoding achacin, an antimicrobial glycoprotein from the body surface mucus of giant African snail Achacina fulica Férussac, was expressed in a methylotrophic yeast, Pichia pastoris, and recombinant achacin (rAch) was secreted in yeast minimal medium in a polyglycosylated form with 80 kDa. Carbohydrate analysis revealed that the glycosylated moiety of rAch was composed of 50 mol mannose and 2 mol N-acetylglucosamine residues. Antimicrobial activity using Escherichia coli and Staphylococcus aureus showed that the rAch had a behavior similar to its native counterpart. The rAch showed so wide an antimicrobial spectrum that 0.1 mg/ml rAch inhibited the growth of Pseudomonas fluorescens, Staphylococcus epidermidis, and Streptococcus faecalis in addition to E. coli and S. aureus, whereas it did not appreciably affect the growth of Proteus mirabilis, Bacillus cereus and Micrococcus luteus. The rAch was also effective in preventing growth of Vibrio anguillarum and Vibrio parahaemolyticus. The results suggested that the rAch had great potential of using as an antimicrobial agent.

Measurements of biological contaminants and particulate matter inside a dwelling in Japan

To investigate the biological contaminant levels inside dwellings in Japan, the authors measured fungal indices, airborne mite allergens (Der 1 and Der 2), and suspended particulate matter (SPM). Measurements were continuously conducted at one dwelling located in Yokosuka-city, Kanagawa. The biosensors for fungal index were set at 12 points inside and 2 points outside the dwelling. An SPM sampler was placed in the living room, and samplers for collecting allergens were placed in the living room and in the washroom. The peak level of the fungal index was recorded during July, which is the rainy season in Japan. The highest value in the dwelling was 6.9 in the toilet, and the second highest was 6.6 near a window in the living room that faces southeast, and behind the sofa. The highest monthly SPM level was 21.5 micrograms/m3 during October, and the highest monthly allergen level (Der 1) in the living room was 25.7 pg/m3 during November. A positive relationship between the fungal index and mite allergens was not observed, and the levels of contaminants were not as those found in other studies. However, further study to investigate the distribution of biological contaminants is needed because indoor temperature and relative humidity are comparatively high.

Raman spectral analysis in the C-H stretching region of proteins and amino acids for investigation of hydrophobic interactions

Raman spectra of amino acids showed complexity in the C-H stretching region (2800-3100 cm(-)(1)) attributed to diversity of CH, CH(2), and CH(3) groups in the side chains, ionization state, and microenvironment. The involvement of specific amino acids in the C-H stretching region of selected proteins, namely, lysozyme, alpha-lactalbumin, beta-lactoglobulin, and their binary mixtures, was investigated by deconvolution using maximum likelihood techniques. The main protein band near 2940 cm(-)(1) was attributed not only to aromatic and aliphatic amino acids but also to many other amino acids. A band near 3065 cm(-)(1) was assigned to aromatic residues, whereas bands near 2880 and 2900 cm(-)(1) corresponded primarily to aliphatic amino acids. Heating at 90 degrees C increased relative intensity near 2940 cm(-)(1) and decreased relative intensity at 2895-2902 cm(-)(1) for lysozyme and its mixtures with alpha-lactalbumin or beta-lactoglobulin. Additional bands at 2812 or 2838 and 3003 cm(-)(1) were observed after heating or in 8 M deuterated urea, reflecting changes upon denaturation.

Gas chromatography/principal component similarity system for detection of E. coli and S. aureus contaminating salmon and hamburger

Coho, Atlantic, Spring, and Sockeye salmon and five commercial samples of hamburger patties were analyzed by processing gas chromatography (GC) data of volatile compounds using the principal component similarity (PCS) technique. PCS scattergrams of the samples inoculated with Escherichia coli and Staphylococcus aureus followed by incubation showed the pattern-shift lines moving away from the data point for uninoculated, unincubated reference samples in different directions with increasing incubation time. When the PCS scattergrams were drawn for samples incubated overnight, the samples inoculated with the two bacterial species and the uninoculated samples appeared as three separated groups. This GC/PCS approach has the potential to ensure quality of samples by discriminating good samples from potentially spoiled samples. The latter may require further microbial assays to identify the bacteria species potentially contaminating foods.

Multiple endocrine neoplasia type 2A with the identical somatic mutation in medullary thyroid carcinoma and pheochromocytoma without germline mutation at the corresponding site in the RET proto-oncogene

A germline mutation either in exon 10 or 11 of the RET proto-oncogene is found in the majority of patients with multiple endocrine neoplasia type 2A (MEN 2A). A 41-year-old female patient was referred for further evaluation of incidentally discovered right adrenal tumor. She had bilateral adrenal pheochromocytomas and medullary thyroid carcinomas detected by endocrinological and radiological examination, and diagnosed as MEN 2A. Molecular genetic testing of the RET exons 10 and 11 exhibited the identical somatic missense mutation at codon 634 in both tumors but did not confirm germline mutations in the corresponding sites. Possible mechanisms for tumorigenesis in this patient are discussed.

Report of the annual statistical survey of the Japanese Society for Dialysis Therapy in 1996

BACKGROUND

Nearly 170,000 patients were treated by maintenance renal replacement therapy (RRT) in Japan in 1996. The current status of Japanese patients on RRT might, in some way, be suggestive for patients on RRT in other countries.

METHODS

The Japanese Society for Dialysis Therapy conducts a questionnaire survey of virtually every dialysis facility in Japan at the end of each year. Here we present the results of our survey of patients undergoing RRT as of the end of 1996, as well as five-year trends (1992-1996) in some of the data.

RESULTS

The response rate was 99.8%. At the end of 1996, there were 167,192 patients on maintenance RRT in Japan (1,328 persons per million population). The numbers of patients on maintenance RRT continued to increase during the five-year period. The gross mortality rate for that period ranged from 9.4% to 9.7%. Cuprammonium rayon was the most commonly used material (24.0%) for dialyzer membranes, followed by cellulose triacetate (18.7%). Approximately 5.0% of hemodialysis (HD) patients had a prior history of surgical release of carpal tunnel. The longer the years on HD therapy, the greater the proportion of patients with a history of such an operation. The predialysis plasma beta 2-microglobulin concentration was highest in patients aged 30 to 45 years and declined slightly after the age of 45. There was no significant difference in the HbA1c level between continuous ambulatory peritoneal dialysis and HD patients, both in whom diabetes was the disease causing renal failure. Moreover, among HD patients with diabetes, there was a clear tendency for the HbA1c level to be higher when the normalized protein catabolic rate was higher.

CONCLUSION

This report summarizes the latest results of the survey on Japanese patients on RRT.

Sperm surface heparin/heparan sulfate is responsible for sperm binding to the uterine envelope in the newt, Cynops pyrrhogaster

The sperm-binding properties of egg envelopes are investigated in the newt, Cynops pyrrhogaster. Sperm binding was only seen on the uterine envelope when acrosome-reacted sperm were inseminated. No acrosome-intact sperm bound to the envelopes. By scanning electron microscopic observation, acrosome-reacted sperm were revealed to bind to a seat-like structure present on the surface of the uterine envelope. Sperm binding to the uterine envelope was inhibited by treatment of eggs with heparin or heparan sulfate, or treatment of acrosome-reacted sperm with heparinase prior to insemination. A molecule with a molecular mass of 75 kDa was purified from the uterine envelope by affinity chromatography with heparin-Sepharose. These results indicated that sperm binding was mediated by heparin-like molecules expressed on the surface of acrosome-reacted sperm and the 75 kDa molecule was present as a constituent of uterine envelopes.

Respiratory health associated with exposure to automobile exhaust. III. Results of a cross-sectional study in 1987, and repeated pulmonary function tests from 1987 to 1990

We conducted an epidemiological study to investigate the association between exposure to automobile exhaust and respiratory health. We selected 3 zones from two geographically different areas in Tokyo on the basis of expected exposure levels: (1) within 20 m from the side of major roads with heavy traffic, (2) between 20 and 150 m from the side of the same road, and (3) a residential district of suburban Tokyo. The subjects of the study were female adults aged 30-59 y. A cross-sectional study of respiratory symptoms and repeated pulmonary function testing were also performed in each zone. The results suggested that exposure to automobile exhaust may be associated with respiratory symptoms. Nevertheless, repeated pulmonary function testing did not reveal any consistent differences. Investigators should conduct additional follow-up studies to investigate the decline of pulmonary functions with age.

Estimated number of patients with chronic renal failure but not with end-stage renal disease in Japan: comparisons between two estimation methods

We estimated the number of patients with chronic renal failure (CRF) but not with end-stage renal disease (ESRD) in Japan by two methods: a nationwide survey and an estimation using incidence rates of ESRD among CRF patients as well as the number of incident ESRD. The former estimated the number of patients with CRF but not with ESRD as 154,000 (95% confidence interval 139,000-168,000), while so did the latter as 142,000 (133,000-150,000). It follows that the number of CRF patients including ESRD could amount to more than 300,000, which would give a substantial impact on public health in Japan. Despite some own methodological issues in estimation, the two estimates were reasonably in good agreement: supporting their methodological validity in estimation, since sources of errors appeared to be quite independent of each other.

Peripheral deletion of gammadelta T cells in haemodialysis patients

Many patients with end-stage renal disease have altered host defenses against infectious agents. We have demonstrated that T cells, which play an important role in the immunological response, may undergo apoptosis by the Fas system in uraemia. To elucidate whether gammadelta T cells, which function as a first defense against intracellular pathogens, are altered in number or characteristics in dialysis patients, surface expressions of TCR, LFA-1 and Fas antigen on peripheral T cells were examined by immunofluorescence analysis. We demonstrated that the proportions of peripheral gammadelta T cells are altered significantly in haemodialysis (HD) patients. Interestingly, there were marked differences in the levels of expression of LFA-1 and Fas antigen between the two types of T cells. Moreover, both the expression of LFA-1 and that of Fas antigen were enhanced significantly in HD patients compared with normal controls. These results suggest that circulating gammadelta T cells may be susceptible to activation-induced cell death in comparison with alphabeta T cells in uraemic environments.