Potential bioavailability of phosphorus in citrus orchard soil to Microcystis aeruginosa

Algal blooms in eutrophic water bodies are controlled by inputs of phosphorus (P) as the growth-limiting nutrient. Runoff particulate P associated with soil from fields often predominates among P fractions. Here, an algal bioassay to investigate the potential bioavailability of particulate P in soil collected from a citrus orchard was conducted. Microcystis aeruginosa was cultured in medium containing soil as the sole source of P. The P in the soil was not notably solubilized after autoclaving. Analyses of chlorophyll-a, suspended solids, particulate organic carbon, and particulate organic nitrogen showed that M. aeruginosa could utilize some of the P present in the soil, perhaps that in particulate form, but this form of P was not sufficient to maintain optimum growth.

Regeneration of articular cartilage defects in the temporomandibular joint of rabbits by fibroblast growth factor-2: a pilot study

The purpose of this study was to investigate the therapeutic usefulness of fibroblast growth factor-2 (FGF-2) in rabbit temporomandibular joints (TMJ) with osteoarthritis. A 10-mm(3) defect was bored in the surface of the mandibular condyle head. The animals were divided into four groups: two test groups in which the defect was filled with lyophilized collagen containing 0.1 or 1.0microg of FGF-2, and two control groups, in which the defects were filled with lyophilized collagen without FGF-2 or left empty. The defective sites were examined under a light microscope 3 weeks after surgery. Initiation of cartilage formation was observed in the defects filled with 0.1microg of FGF-2, but only a small amount of cartilage was found in the defects of the 1.0-mug FGF-2- treated group. In the control groups, soft-tissue repair only or no tissue repair was found. In vivo, a dose of 0.1microg of FGF-2 can stimulate articular cartilage restoration in defects of the TMJ in rabbits, although determining the effective concentration range of FGF-2 may be difficult. The present results suggest that an optimum concentration of FGF-2 could restore defects of TMJ articular cartilage clinically.

Neural Responses to Human Voice and Hemisphere Dominance for Lexical-semantic Processing

Objectives : In our previous functional magnetic resonance imaging (fMRI) study, we determined that there was distinct left hemispheric dominance for lexical- semantic processing without the influence of human voice perception in right-handed healthy subjects. However, the degree of right-handedness in the right-handed subjects ranged from 52 to 100 according to the Edinburgh Handedness Inventory (EHI) score. In the present study, we aimed to clarify the correlation between the degree of right-handedness and language dominance in the fronto-temporo-parietal cortices by examining cerebral activation for lexical-semantic processing.

Methods : Twenty-seven normal right-handed healthy subjects were scanned by fMRI while listening to sentences (SEN), reverse sentences (rSEN), and identifiable non-vocal sounds (SND). Fronto-temporo-parietal activation was observed in the left hemisphere under the SEN - rSEN contrast, which included lexical- semantic processing without the influence of human voice perception. Laterality Indexwas calculated as LI = (L - R)/(L + R) X 100, L: left, R: right.

Results : Laterality Index in the fronto-temporo-parietal cortices did not correlate with the degree of right-handedness in EHI score.

Conclusions : The present study indicated that the degree of right-handedness from 52 to 100 in EHI score had no effect on the degree of left hemispheric dominance for lexical-semantic processing in right-handed healthy subjects.

Neural responses to human voice and hemisphere dominance for lexical-semantic processing--an fMRI study

OBJECTIVES

In our previous functional magnetic resonance imaging (fMRI) study, we determined that there was distinct left hemispheric dominance for lexical-semantic processing without the influence of human voice perception in right-handed healthy subjects. However, the degree of right-handedness in the right-handed subjects ranged from 52 to 100 according to the Edinburgh Handedness Inventory (EHI) score. In the present study, we aimed to clarify the correlation between the degree of right-handedness and language dominance in the fronto-temporo-parietal cortices by examining cerebral activation for lexical-semantic processing.

METHODS

Twenty-seven normal right-handed healthy subjects were scanned by fMRI while listening to sentences (SEN), reverse sentences (rSEN), and identifiable non-vocal sounds (SND). Fronto-temporo-parietal activation was observed in the left hemisphere under the SEN - rSEN contrast, which included lexical-semantic processing without the influence of human voice perception. Laterality Index was calculated as LI = (L - R)/(L + R) x 100, L: left, R: right.

RESULTS

Laterality Index in the fronto-temporo-parietal cortices did not correlate with the degree of right-handedness in EHI score.

CONCLUSIONS

The present study indicated that the degree of right-handedness from 52 to 100 in EHI score had no effect on the degree of left hemispheric dominance for lexical-semantic processing in right-handed healthy subjects.

A functional MRI study: cerebral laterality for lexical-semantic processing and human voice perception

BACKGROUND AND PURPOSE

Language dominance research using functional neuroimaging has made important contributions to clinical applications. Nevertheless, although recent neuroimaging studies demonstrated right-lateralized activation by human voice perception, the influence of voice perception in terms of language dominance has not been adequately studied. We aimed to accurately clarify language dominance for lexical-semantic processing in the temporal cortices by focusing on human voice perception.

METHODS

Thirty normal right-handed subjects were scanned by functional MR imaging while listening to sentences (SEN), reverse sentences (rSEN), and identifiable nonvocal sounds (SND). We investigated cerebral activation and the distribution of individual Laterality Index under 3 contrasts: rSEN-SND, SEN-SND, and SEN-rSEN.

RESULTS

The rSEN-SND contrast, including human voice perception, revealed right-lateralized activation in the anterior temporal cortices. Both SEN-SND and SEN-rSEN contrasts, including lexical-semantic processing, showed left-lateralized activation in the inferior and middle frontal gyrus and middle temporal gyrus. The SEN-rSEN contrast, without the influence of human voice perception, showed no temporal activation in the right hemisphere. Symmetrical or right-lateralized activation was observed in 22 of 27 subjects (81.4%) under the rSEN-SND contrast in the temporal cortices. Although 9 of 27 subjects (33.3%) showed symmetrical or right-lateralized activation under the SEN-SND contrast in the temporal cortices, all subjects showed left-lateralized activation under the SEN-rSEN contrast.

CONCLUSION

Our results demonstrated that right-lateralized activation by human voice perception could mask left-lateralized activation by lexical-semantic processing. This finding suggests that the influence of human voice perception should be adequately taken into account when language dominance is determined.

A new sterility test for cow's milk using alanine racemase gene as the index

Oligonucleotide primers designed from consensus sequences of alanine racemase genes were used for a sterility test of cow's milk by polymerase chain reaction (PCR). Commercial cow's milk in two 250 ml packages was separately centrifuged at 5000 x g for 10 min, bacterial cells in each precipitate were cultivated at 30 and 55 degrees C for 5 h in Luria-Bertani medium, and the cells from each culture were mixed and used for the PCR after being treated with 0.1 N NaOH at 60 degrees C for 10 min. When we performed the PCR using DNAs from various bacteria and eukaryotes as the templates, a unique PCR product of about 390 bp was amplified only from the bacteria. The sensitivity of the PCR method was such that an initial inoculum of 1 CFU of Bacillus stearothermophilus, Escherichia coli, and Pseudomonas fluorescens per 250 ml of cow's milk could be detected. When we analyzed 14 types of commercial cow's milk, all samples which were positive by the standard sterility test at 30 or 55 degrees C were also found positive by the PCR method.

Tissue reaction at the implantation of recombinant human bone morphogenetic protein-2 into the skeletal muscle

Bone morphogenetic protein (BMP) is a unique cytokine that induces bony tissue in soft tissue. Tissue reactions at and around the implantation of recombinant human BMP-2 (rhBMP-2) into the soft tissue of rats and nonhuman primates were investigated. At the osteoinduced site of rats, massive trabeculae-lined osteoblasts and rich marrow were observed. At and around the nonosteoinduced sites of nonhuman primates, large clear nuclei were observed in reaction to rhBMP-2 implantation. The surrounding area was visually classified into zones 1, 2 and 3. Zone 3 was near the center of the implant. The area of nuclei, the major axis, the minor axis and the ratio of minor axis per major axis were image-analyzed in the histological views. In zones 1, 2 and 3, the nuclear areas were 18.0 (3.1) mean (SD); unit micron2, 33.4 (5.61) and 110.1 (23.7), respectively. The major axes of nuclear ellipses were 7.45 (0.22) (unit micron), 7.76 (0.26), and 13.9 (1.88), respectively. The minor axes were 3.07 (0.53), 5.59 (0.95) and 10.1 (1.35), respectively. The ratios of minor axis per major axis of nuclear ellipses were 0.4 (0.57), 0.72 (0.11) and 0.73 (0.11) in zones 1, 2 and 3, respectively. These results showed that in zones 2 and 3 cell and tissue reactions were marked against rhBMP-2 implantation.

Isolation and characterization of a mesenchymal cell line that differentiates into osteoblasts in response to BMP-2 from calvariae of GFP transgenic mice

We established the clonal mesenchymal cell line, GFP-C3 (C3), which differentiates into osteoblasts in response to BMP-2 from calvariae of newborn green fluorescence protein (GFP) transgenic mice. This cell line cultured with control medium expressed low levels of alkaline phosphatase (ALP) activity and osterix mRNA and undetectable ALP and osteocalcin mRNA. Incubation of these cells with rhBMP-2 increased ALP activity dose-dependently and induced substantial levels of ALP, osteocalcin and osterix mRNA expression. C3 cells infected with adenovirus vector encoding BMP-2 (AdBMP-2) or Runx2 (AdRunx2) showed greatly increased ALP mRNA expression in a time-dependent fashion. Transduction with AdRunx2-induced expression of ALP and osteocalcin mRNA, but not osterix mRNA by day 3. Transduction with AdBMP-2 induced apparent expression of ALP and osterix mRNA by day 1 after transduction, but induced only weak expression of osteocalcin mRNA day 3 after transduction. Transplantation of C3 cells transduced with AdBMP-2 into back subfascia in wild-type mice with a complex of poly-d,l-lactic-co-glycolic acid/gelatin sponge (PGS) generated ectopic bone formation involving GFP-positive osteoblasts and osteocytes 2 weeks after transplantation. C3 cells transduced with AdRunx2 or AdLacZ failed to induce ectopic bone formation. Transplantation of C3 cells transduced with AdBMP-2 into craniotomy defects in wild-type mice using PGS as a carrier induced bone formation 2 weeks after transplantation, and replaced defects 4 weeks after transplantation. C3 cells transduced with AdRunx2 failed to induce bone repair after transplantation into craniotomy defects. These results indicate that C3 cells retain differentiation potential into osteoblasts in response to BMP-2. They are useful tools for analyzing the process of osteoblast differentiation in vivo after transplantation.

Simple and effective osteoinductive gene therapy by local injection of a bone morphogenetic protein-2-expressing recombinant adenoviral vector and FK506 mixture in rats

We have previously utilized a human bone morphogenetic protein-2 (BMP-2)-expressing recombinant adenoviral vector (AxCAOBMP-2) for osteoinductive gene therapy in rats. However, immunosuppression is essential for osteoinduction by AxCAOBMP-2 and this is one of the major impediments to its clinical use. Injection of AxCAOBMP-2 together with the immunosuppressant FK506 made it possible to markedly reduce the dose of the immunosuppressive agent and still induce ectopic bone reliably. We injected AxCAOBMP-2 and FK506 into the right calf muscle of rats, while the same number of plaque forming units of AxCAOBMP-2 and the same dose of FK506 placebo (vehicle) were injected into the left calf muscle. At 1, 3, 5, 7, 9 days after injection, BMP-2 mRNA expression was significantly higher in the right calf muscle than in the left calf muscle. At 21 days after injection, significantly more ectopic bone was observed in the right calf muscle than in the left calf muscle. These results indicate that coinjection of FK506 significantly promotes osteoinduction. In addition, local injection of FK506 may also make it possible to prevent a decrease of gene expression with other adenoviral vector.

Flow cytometric detection of cell-associated interleukin-8 in alveolar macrophages in vivo from patients with hypersensitivity pneumonitis and sarcoidosis

In comparison with neutrophil-mediated lung diseases, such as acute respiratory distress syndrome, the involvement of IL-8 in lymphocyte-mediated lung diseases has not been fully investigated. Several reports have shown a slight increase in bronchoalveolar lavage fluid (BALF) IL-8 in patients with hypersensitivity pneumonitis (HP) and sarcoidosis (SAR), but the source of the IL-8 has not been clarified. In the present study, the in vivo production of IL-8 by alveolar macrophages (AMs) is examined in these patients by analyzing the cell-associated IL-8, using the flow cytometric method adopted previously. The IL-8 levels in the epithelial lining fluid (ELF) were also assessed. Initially, slight, but significant, increased levels of ELF IL-8 in HP and SAR were confirmed. Using flow cytometric analysis, a significant increase was found in the cell-associated IL-8 of the freshly isolated AMs in HP, but not in SAR, indicating in vivo production of IL-8 by AMs in HP. The cell-associated IL-8 of the AMs cultured with or without lipopolysaccharide was also analyzed. However, in contrast to previous findings in patients with idiopathic pulmonary fibrosis, no differences were found between SAR and HP patients and control subjects. Based on these findings, it is speculated that ELF IL-8 levels are slightly increased in HP and SAR, and they may contribute to the accumulation of neutrophils and possibly lymphocytes. However, the source of IL-8 may be different and AMs are the candidate source of IL-8 in HP, but not in SAR. The flow cytometric method may be useful in assessing cytokines production by AMs.

A follow-up study on the association of working conditions and lifestyles with the development of (perceived) mental symptoms in workers of a telecommunication enterprise

AIM

This study investigated the association of working conditions and lifestyle with mental health in Japanese workers.

METHODS

A follow-up study was carried out in the Kanto district of Japan of workers in a telecommunications enterprise who received their first annual health check-up between 1992 and 1996 and were between 20 and 54 years old. Workers who reported mental symptoms, had a past history of disease, or current illness at their first check-up were excluded from the analysis. In total, the study included 23 837 workers. The association between working conditions and lifestyle and the development of mental symptoms was investigated by pooled logistic regression analyses.

RESULTS

Working long hours and part-time work, as opposed to normal daytime hours of work, were factors associated with the development of mental symptoms in males, as were smoking, short sleeping hours, little physical exercise, rarely taking three meals a day, frequently eating within 1 h before sleep, much preference for salty meals and little preference for vegetables. Consumption of alcohol was negatively associated with the development of mental symptoms in males. Overall, the results suggested that the lower the Healthy Work and Lifestyle Score, the higher the risk of developing mental symptoms.

CONCLUSIONS

Working conditions and lifestyle, especially food preferences, have an apparent influence on the mental health of Japanese workers. Moreover, the Healthy Work and Lifestyle Score indicates that working conditions and lifestyle appear to have a cumulative influence upon the mental health of Japanese workers.

Preclinical study of recombinant human bone morphogenetic protein-2: application of hyperbaric oxygenation during bone formation under unfavourable condition

The objective of this study was to evaluate the effect of hyperbaric oxygenation on bone formation by recombinant human bone morphogenetic protein-2 (rhBMP-2) under unfavourable conditions. The calf muscles of 10 rats with low-blood supply were prepared by ligating and cutting the right femoral artery, and 10 micro of rhBMP-2 was implanted in the calf muscle. Five rats each were randomly assigned to the hyperbaric oxygenation group and the control group (untreated). The rats in the hyperbaric oxygenation group were treated with hyperbaric oxygenation at 2.0 atmospheres absolute for 3 weeks. In the histologic evaluation, the number of osteoblasts in the hyperbaric oxygenation group was greater than that in control group. The area of the trabecular bone induced in the hyperbaric oxygenation group was significantly larger than that in the control group. The values of alkaline phosphatase activity and calcium contents in the hyperbaric oxygenation group were significantly higher than those in the control group. The results of the present study suggest that hyperbaric oxygenation increases the partial oxygen pressure in low blood supply tissue and accelerates the activity and rate of osteoinduction by rhBMP-2. Hyperbaric oxygenation therapy may increase the clinical application of rhBMP-2 to unfavourable condition.

Transplantation of skin fibroblasts expressing BMP-2 promotes bone repair more effectively than those expressing Runx2

We investigated the osteogenic potential of skin fibroblasts that overexpressed BMP-2 or Runx2 by using adenoviral vectors. In in vitro experiments, skin fibroblasts infected with adenovirus vector encoding BMP-2 (AdBMP-2) released substantial levels of BMP-2 proteins into culture media, and those infected with adenovirus vector encoding Runx2 (AdRunx2) produced its protein. Transduction of BMP-2 or Runx2, respectively, increased alkaline phosphatase (ALP) activity and induced expression of mRNAs of ALP, osteocalcin, and osterix in skin fibroblasts. In in vivo experiments, we investigated the bone induction activity by transplantation of a complex composed of carrier [poly-D,L-lactic-co-glycolic acid/gelatin sponge (PGS)] and skin fibroblasts (PGS/SF complex). Transplantation of PGS/SF complexes composed of skin fibroblasts transduced with AdBMP-2-induced ectopic bone formation when transplanted into the subfascia of back muscle, unlike those infected with AdRunx2. Transplantation of PGS/SF complexes composed of skin fibroblasts transduced with AdBMP-2 into craniotomy defects induced bone formation from 2 weeks after transplantation, and almost all PGS was replaced by newly synthesized bone at 6 weeks. To investigate the fate of the transplanted cells, we transplanted skin fibroblasts isolated from green fluorescence protein transgenic mice into craniotomy defects. Transplantation of these skin fibroblasts transfected with AdBMP-2 generated green fluorescence protein-positive osteoblasts and osteocytes, indicating that the transplanted skin fibroblasts differentiated into osteoblastic lineage cells during bone repair. In contrast, transplantation of PGS/SF complexes composed of skin fibroblasts transduced with AdRunx2 induced a few ALP-positive cells at 1 week after transplantation, but their number decreased depending on time after transplantation. In addition, transplantation of these complexes was insufficient to induce bone repair. Taken together, our results suggest that skin fibroblasts expressing BMP-2 are more suitable for cell-mediated therapy of bone repair than those expressing Runx2.

Identification of a novel gelsolin truncate in the vertical and metastatic phase malignant melanomas

Examination of 38 human melanoma samples by Western blotting analysis with anti-gelsolin antibodies showed that a new 85 kDa truncated gelsolin (GSNp85), co-expressed with wild-type gelsolin, was frequently expressed in vertical growth phase melanomas (Clark level II-IV) and metastatic growth phase melanomas. The GSNp85 truncate was not expressed in radial growth phase melanomas (Clark level I), acquired naevi, other skin cancers or normal skin tissues. Peptide-sequencing analysis revealed that GSNp85 lacks the C-terminal domain of wild-type gelsolin at the region containing the caspase-8 recognition site IETD. Caspase-8 processing was detected in GSNp85-positive but not GSNp85-negative melanomas. These data suggest that GSNp85 is a cleavage product of caspase-8 and may be useful as a new marker for the vertical or metastatic growth phase of malignant melanoma.