Influences of protein ingestion on glucagon‐like peptide (GLP)‐1‐immunoreactive endocrine cells in the chicken ileum

Influences of a specific dietary nutrient on glucagon‐like peptide (GLP)‐1‐containing cells in the chicken intestine are not yet clear. Significance of dietary protein level on GLP‐1‐containing cells in the chicken ileum was investigated. Chickens fed control or experimental diets of varying protein levels were examined using immunohistochemical and morphometrical techniques. We show that the protein ingestion had an impact on the activities of GLP‐1‐immunoreactive cells in the chicken ileum. Weight gains declined with decreasing dietary crude protein (CP) levels, but no significant differences were detected in the daily feed intake and villous height. GLP‐1‐immunoreactive cells with a round or oval shape were frequently observed in the lower CP level groups (4.5% and 0%). Frequencies of occurrence of GLP‐1‐immunoreactive cells were 41.1 ± 4.1, 38.5 ± 4, 34.8 ± 3.1 and 34.3 ± 3.7 (cells/mm², mean ± SD) for dietary CP level of 18%, 9%, 4.5% and 0% groups, respectively and significant differences were recognized between the control and lower CP level groups (P < 0.05). Multiple regression analysis indicated a significant correlation between the daily protein intake and frequencies of occurrence of GLP‐1‐immunoreactive cells. The protein ingestion is one of the signals that influence GLP‐1‐containing cells in the chicken small intestine.     

Pyrolysis of lignin in the presence of tetramethylammonium hydroxide: a convenient method for S/G ratio determination

Pyrolysis-gas chromatography in the presence of tetramethylammonium hydroxide (TMAH) was applied to the determination of the ratio of the abundances of the syringyl beta-aryl ether subunits to those of the guaiacyl equivalents (S/G) in lignin. Diazomethane-methylated kenafs (Hibiscus cannabinus and Hibiscus sabdariffa) and beech (Fagus crenata) in situ lignins were employed. Relative abundances of pyrolysis products derived from the guaiacyl and syringyl beta-aryl ether subunits were determined. The S/G ratios for in situ lignins were obtained with average 3.1% relative standard deviation for a minimum of six repeated runs. The S/G ratios determined by pyrolysis in the presence of TMAH agreed well with those determined by thioacidolysis, with a significant linear regression (R(2) = 0.9867). The results showed that pyrolysis with TMAH is an effective tool for obtaining information on the S/G ratio for in situ lignins.     

Angiotensin I-converting enzyme inhibitory peptides in a hydrolyzed chicken breast muscle extract

The blood pressure of spontaneously hypertensive rats (SHRs) decreased after oral administration of an extract prepared from chicken breast muscle, falling maximally to 50 mmHg lower than before. This effect continued for at least 4 h after administration. The peptides possessing hypotensive activity in the chicken extract were examined by measuring the inhibitory activity (IC(50)) against angiotensin I-converting enzyme (ACE). The inhibitory activity of the chicken extract was 1060 mg%, whereas the activity of the extract treated with an Aspergillus protease and gastric proteases (trypsin, chymotrypsin, and intestinal juice) became stronger, reaching 1.1 mg%. Peptides in this hydrolysate of the extract were isolated by HPLC on a reversed-phase column, and their N-terminal sequences were analyzed. Three peptides possessed a common sequence, Gly-X-X-Gly-X-X-Gly-X-X, which was homologous with that of collagen. The peptide Gly-Phe-Hyp-Gly-Thr-Hyp-Gly-Leu-Hyp-Gly-Phe showed the strongest inhibitory activity (IC(50) = 42 microM).     

Use of an automatic cell-counting system with LED illumination for enumeration of marine bacteria

ABSTRACT:   The concentration of aquatic bacteria is basic information required to evaluate the status of environments and to assess bacterial contribution to material cycles. However, the standard direct counting method using epifluorescence microscopy (EFM) is tedious and there is variation in the counts among workers. Here an automatic counting system that consists of Bioplorer (BP) and image analysis has been applied to marine bacteria. BP is composed of a light-emitting diode (LED) illuminant, an optical unit, a driving stage and a charge-coupled device camera. In combination with fluorescent labeling and simplified membrane filtration, bacteria are enumerated automatically. The reproducibility, sensitivity and accuracy of the system were tested for natural marine bacteria, in comparison with EFM and flow cytometry (FCM). The counts obtained by BP showed good correlation with those obtained by EFM and FCM methods. The counts were significantly higher in inshore and oceanic samples, indicating high sensitivity with low background noise. Considering its reproducibility, objectivity, ease of use and compact size, BP can be used as a routine tool for counting aquatic bacteria in substitution for EFM or FCM.     

Characterization of depth-related changes and site-specific differences of microbial communities in marine sediments using quinone profiles

ABSTRACT:   Respiratory quinone compositions were analyzed by a high-performance liquid chromatography to characterize the depth-related changes and site-specific differences of microbial communities in marine sediments. Two deep-sea sediment samples and one coastal sediment sample were investigated from three sites on the coast of Japan, Sagami Bay, Suruga Bay and Tokyo Bay. Although depth-related changes in microbial community structures were observed, site-specific differences appeared to have greater influence on overall community structures. A variety of quinone homologs was commonly identified at all sampling sites and depths examined, but a few minor quinone fractions, mainly derived from Actinobacteria , were detected only at specific sampling sites. Methylmenaquinone-7 (MMK-7) was the major component throughout the examined depths in Sagami Bay and Tokyo Bay. Most abundant quinone homologs changed with each depth in Suruga Bay. Menaquinone-6 (MK-6) predominated in the 0 to 2-cm layer (19%). Below 0–2 cm, the most abundant homolog in each sampling depth was phylloquinone (K₁; 13%, 4–6 cm), MK-8 (19%, 8–10 cm) and MK-7 (13%, 16–18 cm). The microbial respiratory quinone profiling method shown here, successfully demonstrates the usefulness of this approach to characterize microbial communities in marine sediments.     

Synergetic effects of cell immobilization in polyurethane foam and use of thermotolerant strain on degradation of mixed hydrocarbon substrate by Prototheca zopfii

ABSTRACT:   The synergetic effects of an immobilized cell system in an oleophilic polyurethane foam (PUF) and use of a thermotolerant strain on degradation of hydrocarbons by colorless green microalga Prototheca zopfii are reported. Two strains of P. zopfii , i.e. thermotolerant RND16 and non-thermotolerant ATCC30253, were immobilized in PUF to compare their abilities to biodegrade a mixed hydrocarbon substrate (MHS) containing aliphatic and polycyclic aromatic hydrocarbons (PAHs), as a function of temperature. The thermotolerant strain RND16 degraded MHS at 35°C, while ATCC30253 did not degrade hydrocarbons at temperatures higher than 30°C. Immobilization of P. zopfii in PUF resulted in shortened lag for growth-associated biodegradation of n -alkanes in MHS, the effect of which was most significant in cultures of RND16 at 25°C. Nevertheless, the decrease in the amount of degraded PAHs was caused by PUF immobilization and the level of this decrease was marked in the cultures of RND16, in which rate and extent of n -alkane degradation were higher than for ATCC30253.     

Trehalose may prevent postsurgical adhesions in a rabbit model of hysterotomy

The adhesion-preventing effect of trehalose in visceral organs was evaluated in a rabbit model. All rabbits underwent a hysterotomy, during which mild abrasion and desiccation was induced on the surfaces of visceral organs. In the control group, the intestines were kept dry during hysterotomy. In the saline and trehalose groups, saline solution and 7% trehalose solution, respectively, were sprayed on the organ surfaces. Adhesion formation on organ surfaces on which abrasion and desiccation were induced declined significantly in the trehalose group compared with the other groups. In contrast, at the hysterotomy site, there was no significant difference in adhesions between groups, suggesting that trehalose prevents adhesions in organs that have developed minor inflammation by abrasion and desiccation.     

Echocardiographic estimation of left atrial pressure in beagle dogs with experimentally-induced mitral valve regurgitation

Non-invasive and immediate estimation of left atrial pressure (LAP) is very useful for the management of mitral regurgitation (MR), and many reports have assessed echocardiographic estimations of LAP to date. However, it has been unclear of which examination and evaluate article possess the best accuracy for the MR severity. The present research aims to establish the echocardiographic estimation equation of LAP that is well applicable for clinical MR dogs. After the chordae tendineae rupture was experimentally induced via left atriotomy in six healthy beagle dogs (three males and three females, two years old, weighing between 9.8 to 12.8 kg), a radio telemetry transmitter catheter was inserted, which allows the continuous recordings of LAP without the use of sedation. Approximately 5 weeks after the surgery, echocardiographic examination, indirect blood pressure measurement, measurement of plasma atrial natriuretic peptide (ANP) and LAP measurement by way of the radio telemetry system was performed simultaneously. Subsequently, simple linear regression equations between LAP and each variable were obtained, and the equations were evaluated whether to be applicable for clinical MR dogs. As a result, the ratio of early diastolic mitral flow to early diastolic lateral mitral annulus velocity (E/Ea) had the strongest correlation as maximum LAP=7.03*(E/Ea)-54.86 (r=0.74), and as mean LAP=4.94*(E/Ea)-40.37 (r=0.70) among the all variables. Therefore, these two equations associated with E/Ea should bring more precise and instant estimations of maximum and mean LAP in clinical MR dogs.     

Developmental competence of cat oocytes from ovaries stored at various temperature for 24 h

We conducted two experiments to investigate the effects of storage temperature and period for cat ovaries on the meiotic and developmental competence of oocytes collected from the ovaries. In Experiment 1, ovaries were stored in physiological saline for 24 h at 4 C, 23-25 C, or 38 C (cold, room, and incubator temperature groups, respectively), and then oocytes were collected from the ovaries in each group. Morphologically intact oocytes were then selected and cultured in maturation medium for 24 h. Significantly more oocytes reached metaphase II (MII) in the cold temperature group (53.4%) than in the room and incubator temperature groups (20.0 and 2.4%, respectively). In Experiment 2, ovaries were stored in physiological saline at room temperature for 0, 6, 12 or 18 h, and then they were stored at 4 C (cold storage) until reaching a total storage period of 24 h. After storage of the ovaries, morphologically intact oocytes were matured, fertilized with frozen-thawed spermatozoa, and cultured in vitro. The rates of morphologically intact oocytes obtained from the ovaries stored at room temperature for 0, 6, 12 or 18 h were 35.3, 30.0, 26.4 and 14.7%, respectively, and the rates of intact oocytes that reached MII were 63.2, 36.4, 26.5 and 11.9%, respectively. The results suggested that the numbers of morphologically intact oocytes and intact oocytes that reached MII after in vitro maturation decrease gradually as the period of storage at room temperature before cold storage increases. Only oocytes from ovaries stored for 6 h developed to the blastocyst stage after in vitro maturation and fertilization when ovaries were stored at room temperature before cold storage. These results indicate that 24 h storage of ovaries at high temperatures (>23 C) decreases the meiotic competence of oocytes. The quality and developmental competence of oocytes are influenced by the length of storage at room temperature before cold storage.