Three-dimensional reconstruction of intramuscular collagen networks of bovine muscle: A demonstration by an immunohistochemical/confocal laser-scanning microscopic method

We undertook a three‐dimensional reconstruction of intramuscular collagen networks of bovine muscle using an immunohistochemical/confocal laser‐scanning microscopic method. By immunohistochemical staining, type I and III collagens were observed mainly in the perimysium, while type IV collagen was observed in the endomysium. On the other hand, type V and VI collagens were observed in both the perimysium and endomysium. By confocal laser‐scanning microscopy, the collagen observed in the perimysium was three‐dimensionally reconstructed as plate‐shaped layers whereas the collagen observed in the endomysium surrounded myofibers. The three‐dimensionally reconstructed observations using immunohistochemical/confocal laser‐scanning microscopic method is useful for investigating collagen networks in muscle.     

Rhizoctonia Blight of Yacon Caused by Rhizoctonia solani AG-1 (IB)

Severe blight of stems and leaves caused by Rhizoctonia solani AG-1 (IB) was found on yacon (Smallanthus sonchifolius), a Compositae tuber crop, grown in Ehime Prefecture, Japan, from August to September 1996 and 1999. We named it “Rhizoctonia blight of yacon” as a new disease. Received 15 October 2001/ Accepted in revised form 25 November 2001     

Identification of overwintering vegetative cells of the bivalve-killing dinoflagellate <Emphasis Type="Italic">Heterocapsa circularisquama</Emphasis> in Uranouchi Inlet,Kochi Prefecture,Japan

ABSTRACT:   Red tides of Heterocapsa circularisquama have led to serious damage of bivalve aquacultures in western coastal areas of Japan. To understand the whole picture regarding the ecology of this species, it is essential to clarify its overwintering mechanisms. In this study, the population dynamics of H. circularisquama were investigated from February 2004 to November 2005, and overwintering cells were identified for the first time in water columns of Uranouchi Inlet, Kochi Prefecture, Japan. Heterocapsa circularisquama cells were detected by the indirect fluorescent antibody technique using monoclonal antibodies that specifically recognize and react to this species. Vegetative cells were almost always detected from the first observation in February 2004 to November 2005 with temperatures of 10.5–30.6°C. During the period from winter to spring, this species survived in areas with a temperature higher than 10°C. The overwintering cells of H. circularisquama were isolated in March 2004, and identification was made via observation of the morphology and body scales of the cultured cells. These overwintering cells were identified as H. circularisquama and reacted to the monoclonal antibody. These results indicate that H. circularisquama can overwinter and survive throughout the year in a vegetative cell state in Uranouchi Inlet.     

Physicochemical and microbiological qualities of steamed and irradiated ground black pepper (Piper nigrum L.)

The effects of steam and irradiation treatments on the physicochemical properties (moisture content, pH, extractable yield, reducing sugar, soluble pigment, antioxidant activity, piperine, Hunter's color, and sensory attributes) and microbiological quality (total aerobic bacteria, coliforms, and yeasts and molds) of ground black pepper stored at refrigerated and room temperatures for 6 months were compared and evaluated. Irradiation resulted in a higher microbial reduction in pepper, with minimal effects on the proximate composition, functional components, color, and sensory attributes of the spice. Steamed peppers appeared darker, and a considerable decrease in the piperine content was observed after treatment and storage. This study illustrates that irradiation is a better decontamination method than steam treatment in eliminating microorganisms without apparently affecting the quality of the powdered spice. Storage at 4 degrees C enhanced the microbial quality and minimized the loss of piperine content in ground black peppers.     

Inhibitory effects of edible marine algae extracts on degranulation of RBL-2H3 cells and mouse eosinophils

Inhibitory effects on degranulation of rat basophilic leukemia (RBL-2H3) cells and mouse eosinophils by marine algae extracts were examined. More than 50% of the degranulation of RBL-2H3 cells was inhibited by water extracts of Ecklonia cava and Chrysymenia wrightii at a concentration of 100 μg/mL. More than 50% of the degranulation of RBL-2H3 cells was inhibited by methanol extracts of Petalonia binghamiae, Scytosiphon lomentaria, Undaria pinnatifida, Porphyra dentata, Codium fragile and Ulva japonica at a concentration of 200 μg/mL. Most inhibitory substances in the methanol extracts were partitioned into ethyl acetate and hexane layers. The ethyl acetate-partitioned layer of methanol extract of Petalonia binghamiae had higher inhibitory effects than the hexane-partitioned layer on the degranulation of RBL-2H3 cells. By contrast, the hexanepartitioned layer of the same extract had a higher inhibitory effect than the ethyl acetate-partitioned layer on the degranulation of mouse eosinophils. The ethyl acetate-partitioned layer of methanol extract of Petalonia binghamiae was further separated into eight fractions by silica gel column chromatography. Most inhibited the degranulation of RBL-2H3 cells, but not that of mouse eosinophils significantly. These results suggest methanol extract of Petalonia binghamiae contains materials that inhibit the degranulation of basophils and eosinophils differentially.     

Suppurative granulomatous sinorhinitis associated with Nocardia spp. infection in a cat

A 9-year-old spayed female cat was examined for cheek skin drainage. The skin lesion did not respond to medical therapy; thereafter, facial deformity developed. A computed tomography revealed an intranasal mass and maxillary osteolysis. The mass was histopathologically diagnosed as suppurative granulomatous inflammation caused by filamentous bacteria. The lesion responded well to radiation therapy. Although actinomycosis was suspected histopathologically, no actinomycetes were detected in the nasal lesion by a bacterial culture conducted at a commercial laboratory. The submandibular lymph node and subcutaneous tissue exhibited swelling. Microbiological examination and genetic analysis based on 16S rDNA gene sequence revealed that Nocardia spp. were isolated from both lesions.     

Modifications of azoxymethane-induced carcinogenesis and 90-day oral toxicities of 2-tetradecylcyclobutanone as a radiolytic product of stearic acid in F344 rats

A 90-day oral toxicity test in rats was performed to evaluate the toxicity of 2-tetradecylcyclobutanone (2-tDCB), a unique radiolytic product of stearic acid. Six-week-old male and female F344 rats (n=15/group) were given 2-tDCB at concentrations of 0, 12, 60 and 300 ppm in a powder diet for 13 weeks. Slight dose-dependent increases in serum total protein and albumin in male rats were found, but these changes were not considered to be a toxic effect. The fasting, but not non-fasting, blood glucose levels of the male rats in the 300 ppm group and female rats in the 60 and 300 ppm groups were lower than those of the controls. Gas chromatography-mass spectrometry analysis showed dose-dependent accumulation of 2-tDCB in adipose tissue, notably in males. Next, we performed an azoxymethane (AOM)-induced two-stage carcinogenesis study. After injection of 6-week-old male F344 rats (n=30/group) once a week for 3 weeks, the animals received 2-tDCB at concentrations of 0, 10, 50 and 250 ppm in a powder diet for 25 weeks. The incidences of colon tumors for the 2-tDCB dosages were 34%, 45%, 40% and 37%, respectively, and were not statistically significant. These data suggest that 2-tDCB shows no toxic or tumor-modifying effects under the present conditions, and that the no-observed-adverse-effect level for 2-tDCB is 300 ppm in both sexes, equivalent to 15.5 mg/kg b.w./day in males and 16.5 mg/kg b.w./day in females.     

Identification of irradiated prawn (Penaeus monodon ) using thermoluminescence and 2-alkylcyclobutanone analyses

Thermoluminescence (TL) and 2-alkylcyclobutanone (2-ACB) analyses were performed to identify irradiated prawns ( Penaeus monodon ). With the TL method, minerals were extracted from prawns using acid hydrolysis. The experimental results satisfied the evaluation criteria of European Norm (EN) 1788, even after low-dose irradiation (0.5 kGy) and a 60 day storage at -20 °C. With the 2-ACB method, 2-dodecylcyclobutanone (2-DCB) and 2-tetradecylcyclobutanone (2-TCB) were successfully extracted from prawns by direct solvent extraction with purification using a conventional silica column and a sulfoxide column, which was used for 2-ACB for the first time. Both 2-ACB derivatives were absent from the non-irradiated samples but were identified in all irradiated samples by gas chromatography-mass spectrometry. Moreover, 2-DCB and 2-TCB production correlated with the applied dose (2.5-10 kGy), and the correlation did not diminish after 60 days of storage at -20 °C for any dose. Therefore, these two techniques provide rapid, simple, and promising methods for routine investigation of frozen prawns.     

Research on the Rice Proteome: The Contribution of Proteomics Technology in the Creation of Abiotic Stress-Tolerant Plants

Proteomics techniques have identified a vast number of proteins that participate in the growth of plants or their adaptation to environmental stresses. Functional analysis of those proteins will contribute to the development of high-yielding crops through artificial manipulation of the basic life phenomena of plants or through the assessment of their stress tolerance. The conditions in almost all farmlands are suboptimal for plant growth, resulting in a calculation that causes the loss to three quarters of the potential yield of crops. Breeding of stress-tolerant cultivars has been hampered by the paucity of information on molecular events underlying stress tolerance. A comparative analysis of the response of plants to stress at the protein level, together with physiological measurements, will assist in identifying the genes and pathways that are crucial for stress tolerance. This review examines analyses of the rice proteome under abiotic stress and the potential contribution of proteomics technology in the creation of abiotic stress-tolerant plants.