Biomedical subjects

Masaru Tanaka

Publications and source records attributed to Masaru Tanaka.

At least 37 records · Page 2Linked to original sources

PubMed2005

Production of mesoscopically patterned cellulose film.

Honeycomb and stripe patterned films were prepared from cellulose triacetate (CTA)/chloroform solution, as a result of the self-organization of the polymer during evaporation of the solvent. The honeycomb patterned CTA films were prepared by two methods, a direct pattern formation method and a transcription method. The latter method gave a well-organized microporous honeycomb pattern. Both types of patterned CTA films were saponified to yield the corresponding patterned cellulose films.

Biocompatible Materials↗

PubMed2005

Analysis of genes developmentally regulated during storage root formation of sweet potato.

To identify the genes involved in storage root formation of sweet potato (Ipomoea batatas), we performed a simplified differential display analysis on adventitious roots at different developmental stages of the storage root. The expression patterns were confirmed by semiquantitative RT-PCR analyses. As a result, 10 genes were identified as being developmentally regulated and were named SRF1-SRF10. The expression of SRF1, SRF2, SRF3, SRF5, SRF6, SRF7, and SRF9 increased during storage root formation, whereas the expression of SRF4, SRF8, and SRF10 decreased. For further characterization, a full-length cDNA of SRF6 was isolated from the cDNA library of the storage root. SRF6 encoded a receptor-like kinase (RLK), which was structurally similar to the leucine-rich repeat (LRR) II RLK family of Arabidopsis thaliana. RNA gel blot analysis showed that the mRNA of SRF6 was most abundantly expressed in the storage roots, although a certain amount of expression was also observed in other vegetative organs. Tissue print mRNA blot analysis of the storage root showed that the mRNA of SRF6 was localized around the primary cambium and meristems in the xylem, which consist of actively dividing cells and cause the thickening of the storage root.

Amino Acid Sequence↗

PubMed2005

Cholecystokinin mRNA in Atlantic herring, Clupea harengus--molecular cloning, characterization, and distribution in the digestive tract during the early life stages.

The mRNA of the peptide hormone cholecystokinin (CCK) was isolated from juvenile Atlantic herring, Clupea harengus, by RT-PCR. The open reading frame encodes a 137 amino acid-long precursor protein. The peptide sequence of herring CCK-8, DYMGWMDF, is identical to that of higher vertebrates and elasmobranchs, and contains methionine in the sixth position from the C-terminus, which has not been reported previously in teleosts. Expression analysis by in situ hybridization shows that positive endocrine-like cells were mainly located in the pyloric caeca and to a less extent in the rectum of the juvenile. A few positive cells were also found in the pyloric portion of the stomach and the intestine. CCK cells were present in all the larvae examined from the day of hatching onwards. Although the CCK cells were scattered throughout the whole midgut, no signals were detected in either the foregut or the hindgut. Since herring larvae have a straight gut, the distribution pattern of CCK cells seems to be reflected in the anatomy of the gut.

Amino Acid Sequence↗

PubMed2005

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephaloapthy (CADASIL): a hereditary cerebrovascular disease, which can be diagnosed by skin biopsy electron microscopy.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited cerebrovascular disease characterized by recurrent subcortical ischemic strokes starting in the third or fourth decade as a result of mutations in the Notch3 gene. Granular osmiophilic material (GOM) deposition around the vascular smooth muscle cells is a specific feature and electron microscopic observations of skin biopsies are useful for this diagnosis. A 39-year-old female with dizziness, abnormal visual fields, and hemiplegia, and a 42-year-old male with tinnitus and dizziness, were suspected of suffering from CADASIL based on MRI findings. Both cases were shown to have characteristic deposits of GOM, 200 to 800 nm in diameter, around the vascular smooth muscle cells of small arteries in the deep dermis, and thus the diagnoses of CADASIL were made, although there was no family history of cerebrovascular disorders or dementia. Dermatologists should be aware of these ultra-structural findings because this disease may occur sporadically and might be more common than initially thought.

Adult↗

PubMed2005

Systemic sclerosis with unusual panniculitis and overlying discoid lupus erythematosus-like lesions.

A 33-year-old men presented with systemic sclerosis accompanied by both unusual panniculitis and overlying discoid lupus erythematosus (DLE)-like skin changes on the left buttock. The lesion did not completely match either lupus erythematosus profundus or morphea profunda but featured clinical and pathological findings halfway between the two entities. No case report of co-existence of systemic sclerosis and morphea profunda was found in the literature, but there are three case reports of patients with systemic sclerosis and lupus erythematosus profundus. One of the three cases had DLE-like changes on the surface of the lesion, a clinical picture similar to our case. We speculated that the DLE-like changes in the overlying skin were due to local tissue ischemia. The accompanying panniculitis in our case was considered to be unique and somehow different from morphea profunda or lupus erythematosus profundus.

Adult↗

PubMed2004

Effect of water structure on blood compatibility--thermal analysis of water in poly(meth)acrylate.

The purpose of this study is to clarify the main factor causing excellent blood compatibility of poly(2-methoxyethyl acrylate)(PMEA) by the comparison between PMEA and seven PMEA analogous polymers. The polymers have a typical functional group as ester side chains such as methoxyethyl, hydroxyethyl, phenoxyethyl, and alkyl groups. The properties of the polymers relating to water were investigated in terms of contact angle, equilibrium water content (EWC), and thermal analysis by differential scanning calorimetry. The water in PMEA could be classified into three types: nonfreezing water, freezing bound water, and free water while the water in the analogous polymers was classified into just two types: free and nonfreezing waters, regardless of the chemical structure of the side chain. The surface property represented by the contact angle of water corresponded to the content of the bound water (nonfreezing water + freezing bound water). The platelet compatibility in vitro did not depend on the contents of these waters, or on the contact angle. On the basis of the results of this work and the previous work on the platelet compatibility of poly(MEA-co-HEMA) (Tanaka et al. Biomacromolecules 2002;3;36-41), the main factor causing the excellent compatibility of PMEA is discussed.

Biocompatible Materials↗

PubMed2004

Quartz crystal microbalance and infrared reflection absorption spectroscopy characterization of bisphenol A absorption in the poly(acrylate) thin films.

The absorption process of bisphenol A (BPA) in a number of poly(acrylate) thin films, such as poly(2-methoxyethyl acrylate) (PMEA), poly(ethyl acrylate) (PEA), poly(n-butyl methacrylate) (PBMA), and poly(methyl methacrylate) (PMMA), has been investigated by quartz crystal microbalance (QCM) and infrared reflection absorption spectroscopy (IRRAS) measurements. Both QCM and IRRAS measurements show that the BPA molecules absorb in PMEA, PEA, and PBMA thin films but not in PMMA thin film. The differences in the BPA absorption behavior are mainly attributed to the difference in the glass transition temperature (T(g)) between these polymers. This absorption behavior also depends on the BPA concentration and polymer film thickness. Furthermore, IRRAS characterization demonstrates that the hydrogen bonding is formed between the hydroxyl group in BPA and the carbonyl group in the poly(acrylate) thin films. BPA molecule absorbed in these polymer thin films can be removed by ethanol rinse treatment. By optimizing experimental conditions for the QCM electrode modified by PMEA thin film, detection limitation of approximately 1 ppb for BPA can be realized by the in situ QCM measurement. This method is expected to be a sensitive in situ detection way for trace BPA in the environmental study.

Journal Article↗

PubMed2004

Water and sediment quality, partial mass budget and effluent N loading in coastal brackishwater shrimp farms in Bangladesh.

The present study aimed to quantify the water and sediment quality and growth and production parameters and to establish nutrient budgets for an average of five selected semi-intensive shrimp ponds in Bangladesh over a growing cycle. Physico-chemical parameters of water and sediments were measured and analyzed by standard methods. Gross yield (kg ha-1) of shrimp was calculated from the stocking and harvesting data. Finally, a partial nutrient mass budget for N and P was calculated. Most of the parameters of water and sediments correlated significantly with each other suggesting a high degree of interactions between different parameters in the system. Significantly higher concentrations of all species of nitrogenous nutrients were recorded in the effluent waters than that entering into the ponds. Therefore, a high loading and net output of nitrogenous nutrients in effluent waters was documented. The study also indicated a net discharge of solids and minerals through effluent loading. However, significantly lower concentrations of phosphorus in the effluent water indicated a net retention and trapping of phosphatic nutrients in the environment. Total production ranged between 532.0 and 697.0 kg ha-1 cycle-1 and P. monodon production between 484.0 and 562.0 kg ha-1 cycle-1. Ponds gained nitrogen primarily from intake water (55%) and fertilizers (29%), and nitrogen was lost primarily from water exchange (78%) and harvested shrimp (12%). Phosphorus gain occurred mostly from intake water (52%) and fertilizers (25%), and phosphorus was lost primarily from water exchange (52%) and harvested shrimp (3.3%). About 10% of input nitrogen and 44% of phosphorus were not accounted for in measured losses, and presumably were fixed or metabolized in the system. On average, 78 g N was discharged to and 25 g P was removed from the surrounding water by the system for each kilogram of shrimp produced. Mean conversion of feed nitrogen and phosphorus to shrimp flesh averaged 74% and 40%, respectively. It was concluded that semi-intensive systems serve as net supplier of N to and net remover of P from the surrounding water.

Animals↗

PubMed2004

Seed supply for coastal brackishwater shrimp farming: environmental impacts and sustainability.

Globally, shrimp farming has been a significant agro-based economic activity since the early 1970s. Because it offered a huge immediate economic return, shrimp farming showed a booming expansion and soon became a multimillion dollar industry. However, it has been under extreme criticism because of its devastating ecological and socio-economic impacts. Because seed is the primary input, the impact from farming has started from the source of seed supply, so that not only are natural stocks of shrimp seeds now overexploited worldwide but seed collection activities also significantly reduce stocks of other living resources. Although hatcheries were developed as potential alternative and have replaced the natural seed source to a great extent, large-scale hatchery productions provide a potential source of coastal pollution. However, this area is still poorly studied. The present paper provides a review of the environmental impacts of the wild shrimp seed fishery as well as the possibility of environmental degradation from artificial shrimp seed production in hatcheries.

Animals↗

PubMed2004

Impacts of pollution on coastal and marine ecosystems including coastal and marine fisheries and approach for management: a review and synthesis.

The history of aquatic environmental pollution goes back to the very beginning of the history of human civilization. However, aquatic pollution did not receive much attention until a threshold level was reached with adverse consequences on the ecosystems and organisms. Aquatic pollution has become a global concern, but even so, most developing nations are still producing huge pollution loads and the trends are expected to increase. Knowledge of the pollution sources and impacts on ecosystems is important not only for a better understanding on the ecosystem responses to pollutants but also to formulate prevention measures. Many of the sources of aquatic pollutions are generally well known and huge effort has been devoted to the issue. However, new concepts and ideas on environmental pollution are emerging (e.g., biological pollution) with a corresponding need for an update of the knowledge. The present paper attempts to provide an easy-to-follow depiction on the various forms of aquatic pollutions and their impacts on the ecosystem and organisms.

Ecosystem↗

PubMed2004

Waste loading in shrimp and fish processing effluents: potential source of hazards to the coastal and nearshore environments.

On average, only 30-40% of the global fishery production is consumed fresh and the rest 60-70% is processed for human consumption and other purposes. Although the proportion of the total fishery production that are processed remained relatively stable over the last decade, the total bulk of processed fishery commodity increased due to the steady increase in the total fishery production. Processing of large bulk of fish, shrimp and other aquatic organisms produces a corresponding large bulk of by-products and wastes. Although recent trend shows that much of these wastes are made into various value added products, considerable quantities are discharged as the processing effluents with large volume of waters used in processing. Reports suggest that fish and shrimp processing effluents are very high in biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), fat-oil-grease (FOG), pathogenic and other microflora, organic matters and nutrients, etc. Fish and shrimp processing effluents are, therefore, highly likely to produce adverse effects on the receiving coastal and marine environments. Although substantial reduction of the waste loads is possible by applying available simple techniques, this is not in practice in most part of the world due to lack of proper managerial and regulatory approach. The present paper reviews the characteristics of fish and shrimp processing effluents as a potential source of coastal and marine pollution and, using the existing data, analyzes the global production and discharge of waste loads from the processing plants and discusses available options for waste treatment and management.

Fisheries↗

PubMed2004

Structural characterization of the dihydroflavonol 4-reductase B (DFR-B) gene in the sweet potato.

A genomic fragment containing the dihydroflavonol 4-reductase B (DFR-B) gene was cloned from the sweet potato (Ipomoea batatas) and its nucleotide sequence was analyzed. The exons and flanking regions were highly homologous to those of previously reported DFR-B genes of the Japanese morning glory, whereas the introns and the intergenic region were less conserved. In addition to the sequences of three miniature inverted-repeat transposable elements (MITEs) and one direct repeat previously reported in the DFR-B gene of Japanese morning glory, two mobile element-like sequences were newly identified in the sweet potato DFR-B gene. At least four allelic sequences were found to exist by amplification of the DFR-B gene from various sweet potato cultivars. One of these allelic sequences had a 2-kb deletion in the intergenic region and was observed in the cultivars with high anthocyanin content in their storage roots.

Alcohol Oxidoreductases↗

PubMed2004

Linear discriminant analysis of dermoscopic parameters for the differentiation of early melanomas from Clark naevi.

As a first step to develop a screening system for pigmented skin lesions, we performed digital discriminant analyses between early melanomas and Clark naevi. A total of 59 cases of melanoma, including 23 melanoma in situ and 36 thin invasive melanomas (Breslow thickness < or =0.75 mm), and 188 clinically equivocal, histopathologically diagnosed Clark naevi were used in our study. After calculating 62 mathematical variables related to the colour, texture, asymmetry and circularity based on the dermoscopic findings of the pigmented skin lesions, we performed multivariate stepwise discriminant analysis using these variables to differentiate melanomas from naevi. The sensitivities and specificities of our model were 94.4 and 98.4%, respectively, for discriminating between melanomas (Breslow thickness < or =0.75 mm) and Clark naevi, and 73.9 and 85.6%, respectively, for discriminating between melanoma in situ and Clark naevi. Our algorithm accurately discriminated invasive melanomas from Clark naevi, but not melanomas in situ from Clark naevi.

Dermatology↗

PubMed2004

Dermoscopic features of mucinous carcinoma of the skin.

BACKGROUND: Dermoscopic features of nonpigmented skin lesions are seldom reported; dermoscopy might be useful in speculating pathologic features in the upper dermis. OBJECTIVE: The objective was to identify additional dermoscopic criteria. METHODS: Dermoscopy of the mucinous carcinoma of the skin occurring on the cheek of a 69-year-old man was performed. RESULTS: We have shown characteristic dermoscopic features of whitish network and light-brown globules and they correspond to the pathologic findings of fibrous septum and mucinous deposition, respectively. DISCUSSION: Dermoscopic examination seemed useful as an adjunct to the diagnosis of this rare nonpigmented malignant neoplasm.

Adenocarcinoma, Mucinous↗

PubMed2004

Product analyses of ozone mediated nitration of benzimidazole derivatives with nitrogen dioxide: formation of 1-nitrobenzimidazoles and conversion to benzotriazoles.

Several benzimidazole derivatives having electron-withdrawing or -donating substituent(s) at the benzene moiety were used as models of the imidazole moiety of purine bases and their nitration with nitrogen dioxide and ozone (so-called Kyodai nitration) were examined. Products were extracted from the reaction mixture with AcOEt and their structures were analyzed. 1-Nitrobenzimidazole derivatives and unexpected 1-nitrobenzotriazole derivatives were identified. Although the yields of 1-nitrobenzimidazole derivatives were quite low, these were all new compounds that could be obtained only by Kyodai nitration. It was speculated that benzotriazoles were formed via 1-nitrobenzimidazoles and subsequent nitration toward benzotriazoles resulted in the formation of 1-nitrobenzotriazoles.

Benzimidazoles↗

PubMed2004

Diagnosis and categorization of acral melanocytic lesions using teledermoscopy.

We performed a multicentre study to test the validity of teledermoscopy for diagnosing acral melanoma and to evaluate inter-observer agreement on the classification of acral melanocytic lesions. Dermoscopic images of 77 acral melanocytic lesions (71 common melanocytic naevi and 6 melanomas) were sent by email to 11 dermatologists with different degrees of experience in dermoscopy. The observers analysed the images on a computer monitor to diagnose acral melanoma or atypical lesions and to categorize all lesions. All 11 observers, regardless of their degree of experience, obtained high values for sensitivity (mean 0.91, SD 0.09) and specificity (mean 0.95, SD 0.04) with regard to the diagnosis of melanoma. The inter-observer agreement was good to excellent (kappa 0.49-0.88) for the categorization of acral melanocytic lesions. All six melanomas were correctly classified as 'atypical pattern' and all observers recommended surgical excision. Teledermoscopy represents a useful tool for the diagnosis of acral melanoma and for the categorization of patterns that suggest benign or potentially malignant acral melanocytic lesions.

Adolescent↗

PubMed2004

Risk of adverse reproductive outcomes associated with proximity to municipal solid waste incinerators with high dioxin emission levels in Japan.

BACKGROUND: Great public concern about health effects of dioxins emitted from municipal solid waste incinerators has increased in Japan. This paper investigates the association of adverse reproductive outcomes with maternal residential proximity to municipal solid waste incinerators. METHODS: The association of adverse reproductive outcomes with mothers living within 10 km from 63 municipal solid waste incinerators with high dioxin emission levels (above 80 ng international toxic equivalents TEQ/m3) in Japan was examined. The numbers of observed cases were compared with the expected numbers calculated from national rates adjusted regionally. Observed/expected ratios were tested for decline in risk or peak-decline in risk with distance up to 10 km. RESULTS: In the study area within 10 km from the 63 municipal solid waste incinerators in 1997-1998, 225,215 live births, 3,387 fetal deaths, and 835 infant deaths were confirmed. None of the reproductive outcomes studied here showed statistically significant excess within 2 km from the incinerators. However, a statistically significant peak-decline in risk with distance from the incinerators up to 10 km was found for infant deaths (p=0.023) and infant deaths with all congenital malformations combined (p=0.047), where a "peak" is detected around 1-2 km. CONCLUSION: Our study shows a peak-decline in risk with distance from the municipal solid waste incinerators for infant deaths and infant deaths with all congenital malformations combined. However, due to the lack of detailed exposure information to dioxins around the incinerators, the observed trend in risk should be interpreted cautiously and there is a need for further investigation to accumulate good evidence regarding the reproductive health effects of waste incinerator exposure.

Air Pollutants↗

PubMed2004

[Thoracoscopic surgery for spontaneous pneumothorax and its anesthetic considerations].

BACKGROUND: Incidence of spontaneous pneumothorax (SPT) is increasing recently. Video-assisted thoracic surgery (VATS) is, at present, accepted generally as a procedure of choice for surgical treatment of SPT. This study was designed to investigate whether pre-operative complications and epidural anesthesia contribute to post-operative outcome following VATS for SPT. METHODS: From 1999 to 2002, 88 patients (78 men and 10 women, ranging in ages from 18 to 86, with an average age of 42 years) presented with SPT and received VATS at the Osaka Police Hospital. We evaluated the relationship between peri-operative risk factors and post-operative outcome after VATS for SPT. RESULTS: Age and epidural analgesia contributed to post-operative pain (P=0.0268 and P=0.0165, respectively). Moreover, old age and long duration of surgery extended a hospitalization period (P=0.0002, r2=0.393 and P=0.0394, r2=0.224, respectively). In addition, old age contributes to post-operative pneumonia (P=0.0405). The patient with history of smoking had prolonged duration of surgery (P=0.0040) and oxygen supply after surgery (P=0.0312). CONCLUSIONS: VATS for SPT is less invasive and contribute to short hospitalization. However, VATS also requires general anesthesia with one-lung ventilation. From our study, peri-operative careful management is necessary in a patient with old age and a habit of smoking.

Adolescent↗