Morphometric analysis of the human tibial nerve and the ageing process

We analysed numbers and sizes of the human tibial nerve branch innervating the soleus muscle. The material was taken from 13 cadavers aged from 67 to 98 years. A linear regression analysis disclosed a significant age-related decrease in the mean number per unit area and the mean transverse area of axons. Such decreases with age may indicate atrophy and loss of motoneurons. Our results could help in understanding the correlation between morphology and function during the ageing process.

Effect of pH on the reduction of nitrite in water by metallic iron

Chemical reduction is an alternative technique to remove nitrogen oxides from contaminated groundwater and closed-surface water body. Metallic iron was employed as a reductant for the reduction of nitrite in water in this study. The effect of pH on the rate and products of nitrite reduction was investigated with a fixed dosage of metallic iron powder (12 mol-Fe/mol-N, size of the powder: 80 mesh). The reduction of nitrite by metallic iron was a pseudo-zero-order reaction under the experimental conditions. The reduction rate of nitrite was increased with decreasing the pH of reaction solution, and the pseudo-zero-order reaction rate constants were 180, 130, 60, 15, 10, and 1 mM/h at pH = 2, 3, 4, 5, 6, and 7, respectively. The reduction products of nitrite were nitrogen gas and ammonium. The yields of nitrogen gas from nitrite reduction were 0.63, 0.74, 0.81, 0.87, 0.92, and 0.98 as molar ratios of nitrogen atom at pH =2, 3, 4, 5, 6, and 7, respectively. Neutral condition enhanced the formation of nitrogen gas from nitrite reduction.

Identification of mutans streptococcal species by the PCR products of the dex genes

A pair of polymerase chain reaction (PCR) primers was designed on the basis of the nucleotide sequence homology of dextranase genes (dex) of Streptococcus mutans, S. sobrinus and S. downei. The primer pair amplified a 530-bp DNA fragment on the dex genes of mutans streptococcal species: S. mutans, S. sobrinus, S. downei, S. rattus and S. cricetus. HaeIII digestion of the 530-bp fragments generated species-specific subfragments, which were easily distinguishable from each other by agarose gel electrophoresis. These results suggest that the PCR-amplification of the dex gene followed by the HaeIII digestion is useful for rapid identification of the five species of mutans streptococci.

Morphometric nerve fiber analysis and aging process of the human inferior alveolar nerve

We studied morphometric nerve fiber analysis and the aging process of the inferior alveolar nerve (IAN). Human IANs were resected at the mandibular foramen. The preparation of sections involved fixation, washing, dehydration, embedding, sectioning and staining as described in our previous reports. We estimated the total number of myelinated axons in the IAN being average 26,200, the transverse area of those being average 37.1 microns 2, the average perimeter of those being 23.0 microns, the average circularity ratio of those being 0.85, respectively. According to these results, the IAN did not demonstrate notable age-relation change in any measured item. The IAN differed from not only our previous data on the human motor peripheral nerves but also those on the human sensory peripheral nerves. With regard to the aging process, the IAN indicated morphological features compared with other peripheral nerves.

[Method-performance studies of notified analytical method for fenbutatin oxide and cyhexatin]

Method-performance studies were conducted for the notified revised analytical method of fenbutatin oxide (FBTO) and cyhexatin (CHT). FBTO and CHT spiked into rice, soybeans, spinach, orange, tea powder and tea extract at the level of 0.5 microgram/g for FBTO and 0.1 microgram/g for CHT were analyzed in replicate in 6 laboratories. Means recoveries of FBTO were 85.2-96.5% and those of CHT were 83.5-89.2% except from soybeans (46.5%). Repeatability relative standard deviation values of FBTO and CHT in each crop were in the ranges of 2.3-9.4% and 3.2-6.3%, respectively. Reproducibility relative standard deviations were 3.9-12.6% for FBTO and 8.3-12.9% for CHT. Detection limits were 0.015-0.05 microgram/g for FBTO and 0.005-0.02 microgram/g for CHT.

Identification of Streptococcus salivarius by PCR and DNA probe

AIMS

To establish species-specific PCR and DNA probe methods for Streptococcus salivarius and to clarify the distribution of dextranase in oral isolates of Strep. salivarius.

METHODS AND RESULTS

A pair of PCR primers and a DNA probe were designed based on the nucleotide sequence of the dextranase gene of Strep. salivarius JCM5707. Both the PCR primer and the DNA probe specifically detected Strep. salivarius but none of the other oral streptococci (23 strains of 13 species). The primer and the probe were capable of detecting 1 pg and 1 ng of the genomic DNA, respectively, purified from Strep. salivarius JCM5707. All oral isolates (130 strains from 12 subjects) of Strep. salivarius from human saliva were positive by both methods.

CONCLUSION

The present PCR and DNA probe methods are highly specific to Strep. salivarius and are useful for the its detection and identification of this bacterium. The dextranase widely distributes among oral isolates of Strep. salivarius.

SIGNIFICANCE AND IMPACT OF THE STUDY

The DNA sequence of a dextranase gene present in the genome of Strep. salivarius is useful as the target DNA of the species-specific PCR and DNA probe.

Nerve fiber analysis and age-related changes of the human mandibular nerve

We morphometrically analyzed nerve fibers of the human mandibular nerve with a discriminative staining method that makes it possible to separate nerve fibers into myelinated and unmyelinated fibers. We counted numbers and transverse areas of myelinated axons under the microscope using an on-line image-analyzer. This study revealed the morphometric changes which affect the human mandibular nerve during the aging process.

Analysis of material and energy flow in sewage treatment facilities in Japan

Energy consumption in sewage treatment facilities in Japan has increased due to increasing tap water consumption. To reduce the resource/energy consumption in sewage treatment facilities, measures such as the selection of optimum treatment processes and operating conditions should be considered. The objective of this study is to gather information necessary for the determination of optimum sewage treatment processes and optimum operating conditions. The energy consumption and material flow in sewage treatment facilities in Japan are analyzed using statistical data. In 1994, reuse rate of treated sewage outside the treatment facilities in Japan was 18% of the amount of domestic treated water. In this regard, reuse of water outside facilities should be encouraged. Average electric power consumption per unit volume of wastewater in sewage treatment facilities varies widely from facility to facility and closely correlates with the facility scale. For example, the smaller the facility scale, the larger the electric power consumption. Treatment volume of sewage in smaller facilities is much less than their capacity. 3.7 million t year-1 of dehydration cake is incinerated and 0.1 million t year-1 of it is converted by composting. The recycle rate of the cake was low. Developing a new sludge treatment process other than incineration is necessary.

Morphometric analysis of myelinated axons in the human vagus nerve

Myelinated axons of the human vagus nerve were analyzed morphometrically on 30 cadavers (16 males and 14 females). The result showed that the transverse area and perimeter of myelinated axons decreased with age, although the total number of their axons did not change.

Auxin is a positive regulator for ethylene-mediated response in the growth of Arabidopsis roots

The requirement of auxin for the ethylene-mediated growth response in the root of Arabidopsis thaliana seedlings was investigated using two ethylene-resistant mutants, aux1-7 and eir1-1, whose roots have been shown to have a defect in the auxin influx and efflux carriers, respectively. A 50% inhibition of growth (I(50)) was achieved with 0.84 microl liter(-1) ethylene in wild-type roots, but 71.3 microl liter( -1) ethylene was required to induce I(50) in eir1-1 roots. In aux1-7 roots, I(50) was not obtained even at 1,000 microl liter(-1) ethylene. By contrast, in the presence of 10 nM 1-naphthaleneacetic acid (NAA), the concentrations of ethylene required to induce I(50) in eir1-1 and aux1-7 roots were greatly reduced nearly to the level required in wild-type roots. Since the action of NAA to restore the ethylene response in aux1-7 roots was not replaced by IAA, an increase in the intracellular level of auxin is likely to be the cause for the restoration of ethylene response. NAA at 10 nM did not inhibit root growth when applied solely, but it was the optimum concentration to recover the ethylene response in the mutant roots. These results suggest that auxin is a positive regulator for ethylene-induced inhibition in root elongation.

Unmyelinated nerve fibers of the human mandibular nerve

The aim of this research is to find and to evaluate morphometorically the unmyelinated nerve fibers in the human mandibular nerve using a light microscope. Our report demonstrates for the first time the presence of the unmyelinated nerve fibers of the human mandibular nerve stained by a special method. Our results also indicate that there is a morphometric change with aging in the unmyelinated axons of the nerve.

Morphological differentiation of nerve fibers: central, peripheral, myelinated and unmyelinated

We have developed a new technique for the morphological differentiation of various nerve fibers which is especially suitable for the morphometric study of nerve fibers of the human nervous system with the help of an image-analyzer. The knowledge from findings by this technique, which is based on several study methods, may be of importance in promoting further neuromorphologic studies and in properly understanding various aspects of neurological symptomatology and the aging process of the nervous system including nerve fibers.

Are there one million nerve fibres in the human medullary pyramid?

It has been the accepted opinion that there are one million nerve fibres in the human medullary pyramid. This seemed to be confirmed in several old reports. But we cannot agree with this opinion. We made nitrocellulose-embedded sections from three normal male brains, and stained them by our modification of Masson-Goldner method. With this method, myelinated axons appeared in blue, whereas the glial processes were coloured in red, which allowed easy discrimination between the two. After morphometric evaluation of the pyramidal axons under the microscope, it appeared without the slightest doubt, that the number of axons does not exceed one-tenth of one million.

Biodegradation of photosynthetically produced extracellular organic carbon from intertidal benthic algae

14C-labeled extracellular products of a natural microphytobenthic community and two species of benthic diatoms (Nitzschia hybridaeformis and Amphora coffeaeformis) were fractionated into extracellular dissolved organic carbon (14C-EDOC), organic carbon extracted with EDTA (14C-EDTA-extractable OC) and extracellular polymeric substances (14C-EPS). The biodegradation of this labeled extracellular organic carbon by bacteria in sediments was examined to determine the processes of enzymatic degradation of photosynthetically-produced extracellular organic carbon from microphytobenthos in an intertidal flat ecosystem. In addition, primary production as well as extracellular enzyme activities (beta- and alpha-glucosidase) were measured to evaluate the possible relationship between organic carbon production and microbiological degradation at the Isshiki intertidal flat in Mikawa Bay, Japan. With all three 14C-fractions extracted from a natural microphytobenthic assemblage and two species of benthic diatoms, more than 50% of the added substrates were mineralized within 24 h by the bacterial community in sediments. At that time, the percentage of high-molecular-weight compounds (>5 K MW) to total MW compounds of 14C-EDTA-extractable OC and 14C-EPS fractions decreased within 24 h from 50.9 to 6.6% and 74.5 to 11.1%, respectively. In situ, beta- and alpha-glucosidase activity in sediment was higher than in the seawater column (at a depth of 1 m), though the photosynthetic production of microphytobenthos was equal to that of phytoplankton. Based on our previous studies that microphytobenthos produced much more extracellular products than phytoplankton, it is assumed from these results that carbon flowing into the microbial loop through the mediation of enzymatic degradation of extracellular products in a benthic system exceeds that in the overlying water column.

Dual Differential Absorption Lidar for the Measurement of Atmospheric SO(2) of the Order of Parts in 10(9)

Vertical concentration profiles of atmospheric SO(2) of the order of parts in 10(9) (ppb) were measured by a multiwavelength differential absorption lidar system. The error that was due to O(3) and aerosols was successfully reduced by a three-wavelength dual differential absorption lidar (DIAL), and a SO(2) concentration of 1.2 ppb for 2400-3000-m altitude was obtained with 300-m range resolution. The measurement error in dual DIAL was estimated to be <1.1 ppb when several factors were considered. The influence of O(3) on SO(2) measurement error was experimentally evaluated from simultaneous measurements of atmospheric SO(2) and O(3) by two conventional DIAL pairs, each using two wavelengths.

Comparison of UDP-glucose:flavonoid 3-O-glucosyltransferase (UFGT) gene sequences between white grapes (Vitis vinifera) and their sports with red skin

The expression of the UDP-glucose:flavonoid 3-O-glucosyltransferase (UFGT) gene has been shown to be critical for anthocyanin biosynthesis in the grape berry. Using white cultivars and bud sports with red skin, we examined the expression of seven anthocyanin biosynthetic genes including the UFGT gene and compared the coding/promoter sequences of the UFGT gene. Northern blot analysis showed that the seven anthocyanin biosynthetic genes were expressed coordinately at higher levels in the red-skin sports than in the white-skin progenitors of the sports. It was especially notable that UFGT gene expression was detected only in the red-skin sports and Kyoho. However, there were no differences in either coding or promoter sequences between Italia (Vitis vinifera) and its red-skin sport Ruby Okuyama, or between Muscat of Alexandria (V. vinifera) and the red-skin sport Flame Muscat. From these findings, the phenotypic change from white to red in the sports is thought to be the result of a mutation in a regulatory gene controlling the expression of UFGT.

A serpin with M(r) 43,000 is a binding protein of M(r) 25,000 protein, a substrate for protein ser/thr kinase detected in Xenopus laevis oocytes

In an attempt to get some clue as to the function of M(r) 25,000 protein, a protein Ser/Thr kinase substrate detected in Xenopus laevis oocytes [Hashimoto, E. et al. (1995) J. Biochem. 118, 453-460], the binding protein was surveyed using the (32)P-labeled protein by casein kinase II as a screening probe. When the cytosolic proteins from oocytes were transferred to a polyvinylidene fluoride membrane and incubated with the labeled protein, only one protein with M(r) 43,000 was visualized on autoradiography. This protein was purified to a nearly homogeneous state through several column chromatography steps. The amino acid sequence of the amino-terminal region of this protein identified it as a kind of serine protease inhibitor (serpin) [Holland, L.J. et al. (1992) J. Biol. Chem. 267, 7053-7059]. However, the M(r) 25,000 protein did not have any effect on the inhibitory action of this serpin on alpha-chymotrypsin. In addition, several binding proteins were also detected in the particulate fraction of oocytes, although the exact identity of these proteins is not clear at this time. These results suggest that the M(r) 25,000 protein may play some role(s) by interacting with these binding proteins in Xenopus oocytes.

Chromosaponin I specifically interacts with AUX1 protein in regulating the gravitropic response of Arabidopsis roots

We have found that chromosaponin I (CSI), a gamma-pyronyl-triterpenoid saponin isolated from pea (Pisum sativum L. cv Alaska), specifically interacts with AUX1 protein in regulating the gravitropic response of Arabidopsis roots. Application of 60 microM CSI disrupts the vertically oriented elongation of wild-type roots grown on agar plates but orients the elongation of agravitropic mutant aux1-7 roots toward the gravity. The CSI-induced restoration of gravitropic response in aux1-7 roots was not observed in other agravitropic mutants, axr2 and eir1-1. Because the aux1-7 mutant is reduced in sensitivity to auxin and ethylene, we examined the effects of CSI on another auxin-resistant mutant, axr1-3, and ethylene-insensitive mutant ein2-1. In aux1-7 roots, CSI stimulated the uptake of [(3)H]indole-3-acetic acid (IAA) and induced gravitropic bending. In contrast, in wild-type, axr1-3, and ein2-1 roots, CSI slowed down the rates of gravitropic bending and inhibited IAA uptake. In the null allele of aux1, aux1-22, the agravitropic nature of the roots and IAA uptake were not affected by CSI. This close correlation between auxin uptake and gravitropic bending suggests that CSI may regulate gravitropic response by inhibiting or stimulating the uptake of endogenous auxin in root cells. CSI exhibits selective influence toward IAA versus 1-naphthaleneacetic acid as to auxin-induced inhibition in root growth and auxin uptake. The selective action of CSI toward IAA along with the complete insensitivity of the null mutant aux1-22 toward CSI strongly suggest that CSI specifically interacts with AUX1 protein.

Mucosal immunization against hepatitis B virus by intranasal co-administration of recombinant hepatitis B surface antigen and recombinant cholera toxin B subunit as an adjuvant

Recombinant cholera toxin B subunit (rCTB) produced by Bacillus brevis carrying pNU212-CTB has been previously found to be a potent mucosal adjuvant to aluminium-non-adsorbed tetanus toxoid (nTT) and diphtheria toxoid (nDT) co-administered intranasally, and the possibility of needle-free inoculation of these vaccines with rCTB has been suggested. In this paper we examined the potentiality of rCTB as a mucosal adjuvant to aluminium-non-adsorbed yeast-derived recombinant hepatitis B surface antigen (rHBs) being a particulate antigen when administered intranasally with rCTB. In-house ELISA showed that a mixture of rHBs (1 or 5 microg) and rCTB (10 microg) elevated not only systemic responses but also mucosal immune responses at the nasal cavity, the lung, the saliva, the small intestine and the vagina against rHBs, and these could be further increased with higher doses of antigen. With antibody isotypes of IgG, there were equally high levels of serum HBs-specific IgG1, IgG2a and IgG2b antibodies and induction of mixed Th1- and Th2-type responses was considered to occur in combination of rHBs and rCTB. Serum anti-HBs titres in almost all mice obtained from sandwich EIA using a commercial kit were higher than 1000 milli-international units ml(-1) (mIU ml(-1)). These results show that rCTB is also very effective as a mucosal adjuvant for a particulate antigen like rHBs, as well as soluble antigens like nTT and nDT reported previously, suggesting the possibility of intranasal immunization with rHBs plus rCTB in humans.

Characterization of microbial community in an activated sludge process treating domestic wastewater using quinone profiles

The dynamics of microbial community structure of activated sludges in a small-scale domestic wastewater treatment process were examined using a novel approach of quinone profiles. The composition and content of quinones in the activated sludges were analyzed monthly over a period of one year. More than 4 types of ubiquinones and 12 types of menaquinones were observed in the activated sludges, with the dominant quinones being ubiquinone (UQ)-8, menaquinone (MK)-7, followed by UQ-10, MK-8 and MK-6. The total quinone contents in the activated sludges varied from 0.93 to 2.68 mumol per gram of particle organic carbon. The molar ratio of ubiquinones to menaquinones (UK/MK) changed from 0.38 to 0.98, indicating that anaerobic bacteria dominated the microbial community of the activated sludges examined. The ratio of UQ/MK varied similar to that of dissolved oxygen in the bulk. The microbial diversity of the activated sludges calculated from the quinone compositions was 13.4-16.8. The diversity of menaquinones was much higher than that of ubiquinones, and increased slightly with increasing temperature. The microorganisms containing menaquinones appear to be sensitive to the change in temperature than those containing ubiquinones.

Senile plaques in an aged western lowland gorilla

Senile plaques (SPs) were found in the cerebral cortex of a 44-year-old Western lowland gorilla (Gorilla gorilla gorilla). All the SPs were obtained as dense assemblies consisting of fibrous materials by silver impregnation, but were not detected by Congo red. More SPs were detected by immunostaining for amyloid beta protein (A beta) and a half of A beta-positive-SPs were also immunoreactive for apolipoprotein E. Moreover, all SPs were immunoreactive for A beta 42 and A beta 43, but not for A beta 40. SPs also did not contain A beta precursor protein-positive structures. These findings suggested that SPs in this case were diffuse plaques. To our knowledge, this is the first report of SPs in the gorilla.

Effects of temperature on biodegradation characteristics of organic pollutants and microbial community in a solid phase aerobic bioreactor treating high strength organic wastewater

The BOD removal rate and microbial community structure in a solid phase aerobic bioreactor using polyvinyl alcohol gel particles as packing material for the treatment of high strength organic wastewater were investigated at various temperatures. The BOD removal rate in the bioreactor increased when the temperature increased from 20 degrees C to 30 degrees C, 40 degrees C, and 50 degrees C, but it decreased when the temperature increased from 50 degrees C to 60 degrees C. Higher temperature enhanced the endogenous respiration of microbes in the bioreactor. The microbial community structure in the bioreactor was analyzed with quinone profile. The experimental results showed that the microbial community structure in the bioreactor was significantly affected by temperature. The dominant quinone of the microbes inhabiting the bioreactor was ubiquinone-8 at 30 degrees C, but that at 50 degrees C and 60 degrees C was menaquinone-7. It was estimated that the thermophilic Bacillus having menaquinone-7 dominated in the bioreactor at higher temperature. The microbial diversity in the bioreactor varied with temperature.

Isolation and expression of the ecdysteroid-inducible angiotensin-converting enzyme-related gene in wing discs of Bombyx mori

We isolated a clone encoding a putative angiotensin-converting enzyme-related gene from the wing disc cDNA library of the silkworm, Bombyx mori (refer to as BmAcer). The predicted open reading frame encoded 648 amino acids with about 50% identities with the Drosophila melanogaster angiotensin-converting enzyme Ance and Acer. Northern analysis identified a 2.2-kilobase mRNA which was abundant in wing discs two days after the beginning of wandering. An accumulation of the transcript was observed approximately 2 h after 20-hydroxyecdysone (20E) exposure in vitro and was blocked slightly by a protein synthetic inhibitor. These data suggest that the transcription of the BmAcer gene is directly 20E-inducible.

Sexual dimorphism of the motoneurons in the human spinal cord

There have been few morphometric studies on the size of the motoneurons of the human spinal cord. The purpose of the present study is to report the differences in the size of the motoneurons between males and females in the human spinal cord. We examined numbers and transverse cell body areas of the motoneurons of the anterior horn using 16 male and 21 female human spinal cords at levels C5 and L3. The sizes of the motoneurons were larger in males than in females, but their numbers were practically the same. These results can be of great importance in setting standard values for the understanding of morphological and functional correlations.

PCR for detection and identification of Streptococcus sobrinus

Oligonucleotide primers were designed based upon a comparison of the dextranase gene (dex) sequences from Streptococcus sobrinus and S. mutans. The primers amplified a 1610-bp long DNA fragment on the dex gene by a PCR. The pair of primers was specific to S. sobrinus as the other members of the mutans streptococci - S. mutans, S. downei, S. cricetus, S. rattus, S. macacae and S. ferus - gave no PCR products. Other gram-positive oral bacteria (15 strains of 10 species of cocci and 18 strains of 12 species of rods) and gram-negative oral bacteria (3 strains of 3 species of cocci and 31 strains of 22 species of rods) also gave negative results in the PCR. The PCR procedure was able to detect as little as 100 fg of purified chromosomal DNA or as few as 9 cfu of S. sobrinus NIDR6715. Seven clinical isolates of S. sobrinus were also positive in the dex PCR. This laboratory developed the S. mutans-specific PCR (dexA PCR) method with the primers specific for a portion of the dextranase gene of S. mutans Ingbritt. Primers for the dex and dexA PCR methods detected two species exclusively from the mutans streptococci. Furthermore, these two species were effectively differentiated by the species-specific amplicons with different lengths. The application of the PCR method to human dental plaque showed that the prevalence of S. sobrinus (83%) in oral cavities was higher than currently supposed (0-50%). These results suggest that the described PCR method is suitable for the specific detection and identification of human cariogenic bacteria, S. sobrinus and S. mutans.