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Biomedical subjects

Y Mori

Publications and source records attributed to Y Mori.

At least 127 records · Page 7Linked to original sources
PubMed2001

Impact of harmonic imaging and transducer frequency on 'ventricular volume' measurements using real-time three-dimensional echocardiography: studies in an in vitro model.

AIMS: Harmonic imaging has increased the yield of quantifiable scans in two-dimensional echocardiography. Although real-time three-dimensional echocardiography avoids geometric assumptions in volume analysis, accurate measurement can be limited by image quality. This study compared volumes from a balloon model mimicking the left ventricle, scanned with and without harmonic imaging, using real time three-dimensional echocardiography. METHODS: Two balloons separated by ultrasound gel were suspended in a water bath. To mimic different chamber volumes, 12 volumes of water within the inner balloon (40-180ml) were scanned using a 3.5MHz probe at fundamental frequency and using a 2.5MHz probe with and without harmonic imaging. RESULTS: Scanning at 3.5MHz, the long axis (B) scans did not significantly underestimate the balloon volume but the 'short axis' (C) scans did (mean difference from actual volumes -0.7-1.4ml, P=0.14 - 3.9 +/- 1.2 ml,P < 0.0001 for B and C scans, respectively). Scanning at 2.5MHz both B and C scans significantly underestimated even more the true volume, C scans to a greater extent (mean difference -6.9 +/- 2.4ml and -11.2 +/- 4.0ml for B and C scans respectively,P < 0.0001 in both cases). However with harmonic imaging, transmitting at 1.7MHz and receiving at 2-4MHz, there was no significant difference of either B or C scans from the reference values (mean difference of B scans -1.2 +/- 1.9ml, P=0.06 and C scans -0.6 +/- 2.2ml, P=0.4). CONCLUSION: The enhanced resolution provided by harmonic imaging improves accuracy of volume analysis by real-time three-dimensional echocardiography.

Analysis of Variance↗
PubMed2001

Alternans of ventricular gradient during percutaneous transluminal coronary angioplasty.

We evaluated the influence of local myocardial ischemia induced by acute coronary occlusion during percutaneous transluminal coronary angioplasty (PTCA) on the ventricular gradients (VG) and investigated whether 2:1 alternans of VG occurs. Twenty-seven patients with angina pectoris, who had one-vessel coronary artery stenosis, were studied. The VG of each consecutive heartbeat before, during, and after PTCA over a 22-second interval was calculated using a microcomputer. The standard deviation and coefficient of variation of magnitude were used as indices of VG variability. Frequency-domain analysis of time series consisting of beat-to-beat VG magnitude for a 22-second interval was also performed by the maximum entropy method. The standard deviation and coefficient of variation of VG magnitude during PTCA were significantly greater than those before and after PTCA (P <.01, P <.01, respectively), and the indices before PTCA were also significantly greater than those after PTCA (P <.05). The maximum power spectrum peaks around 0.5 cycles/beat during PTCA were significantly greater than those after PTCA (P <.01); this suggests that the enhancement of VG alternans is reflected by 2:1 alternans of the action potential in the acute local ischemic myocardium during PTCA.

Adult↗
PubMed2001

Noninvasive assessment of left ventricular isovolumic contraction and relaxation with continuous wave Doppler aortic regurgitant velocity signals: an in vivo validation study.

The purpose of this study was to provide fundamental in vivo validation of a method with the use of aortic regurgitant (AR) jet signals recorded with continuous wave (CW) Doppler for assessing left ventricular (LV) isovolumic contraction and relaxation. Preliminary studies have suggested that analysis of CW Doppler AR velocity signals permits the estimation of LV positive and negative dP/dt. We studied 19 hemodynamically different states in 6 sheep with surgically induced chronic aortic regurgitation. CW AR velocity spectra and high-fidelity LV and aortic pressures were recorded simultaneously. Rates of LV pressure rise and fall (RPR and RPF) were calculated by determining the time interval between points at 1 m/s and 2.5 m/s in the deceleration and acceleration slopes of the CW Doppler AR velocity envelope (corresponding to a pressure change of 21 mm Hg). RPR and RPF calculated by CW Doppler analysis for each state were compared with the peak positive dP/dt and negative dP/dt, obtained from the corresponding high-fidelity LV pressure curve, respectively. The LV peak positive and negative dP/dt derived by catheter ranged from 817 to 2625 mm Hg/s and from 917 to 2583 mm Hg/s, respectively. Multiple regression analysis showed that Doppler RPR correlated well with catheter peak positive dP/dt (r = 0.93; mean differences, -413 +/- 250 mm Hg/s). There was also good correlation and agreement between Doppler RPF and the catheter peak negative dP/dt (r = 0.89; mean difference, -279 +/- 239 mm Hg/s). Both Doppler-determined RPR and RPF underestimated their respective LV peak dP/dt. CW Doppler AR spectra can provide a reliable noninvasive estimate of LV dP/dt and could be helpful in the serial assessment of ventricular function in patients with aortic regurgitation.

Animals↗
PubMed2001

Quantification of aortic regurgitation by real-time 3-dimensional echocardiography in a chronic animal model: computation of aortic regurgitant volume as the difference between left and right ventricular stroke volumes.

BACKGROUND: The accuracy of conventional 2-dimensional echocardiographic and Doppler techniques for the quantification of valvular regurgitation remains controversial. In this study, we examined the ability of real-time 3-dimensional (RT3D) echocardiography to quantify aortic regurgitation by computing aortic regurgitant volume as the difference between 3D echocardiographic-determined left and right ventricular stroke volumes in a chronic animal model. METHODS: Three to 6 months before the study, 6 sheep underwent surgical incision of one aortic valve cusp to create aortic regurgitation. During the subsequent open chest study session, a total of 25 different steady-state hemodynamic conditions were examined. Electromagnetic (EM) flow probes were placed around the main pulmonary artery and ascending aorta and balanced against each other to provide reference right and left ventricular stroke volume (RVSV and LVSV) data. RT3D imaging was performed by epicardial placement of a matrix array transducer on the volumetric ultrasound system, originally developed at the Duke University Center for Emerging Cardiovascular Technology. During each hemodynamic steady state, the left and right ventricles were scanned in rapid succession and digitized image loops stored for subsequent measurement of end-diastolic and end-systolic volumes. Left and right ventricular stroke volumes and aortic regurgitant volumes were then calculated and compared with reference EM-derived values. RESULTS: There was good correlation between RT3D left and right ventricular stroke volumes and reference data (r = 0.83, y = 0.94x + 2.6, SEE = 9.86 mL and r = 0.63, y = 0.8x - 1.0, SEE = 5.37 mL, respectively). The resulting correlation between 3D- and EM-derived aortic regurgitant volumes was at an intermediate level between that for LVSV and that for RVSV (r = 0.80, y = 0.88x + 7.9, SEE = 10.48 mL). RT3D tended to underestimate RVSV (mean difference -4.7 +/- 5.4 mL per beat, compared with -0.03 +/- 9.7 mL per beat for the left ventricle). There was therefore a small overestimation of aortic regurgitant volume (4.7 +/- 10.4 mL per beat). CONCLUSION: Quantification of aortic regurgitation through the computation of ventricular stroke volumes by RT3D is feasible and shows good correlation with reference flow data. This method should also be applicable to the quantification of other valvular lesions or single site intracardiac shunts where a difference between right and left ventricular cavity stroke volumes is produced.

Animals↗
PubMed2001

The effect of topical CS-088, an angiotensin AT1 receptor antagonist, on intraocular pressure and aqueous humor dynamics in rabbits.

PURPOSE: To evaluate the ocular hypotensive effect of topical CS-088, an angiotensin AT1 receptor antagonist, and the effect of CS-088 on aqueous humor dynamics. METHODS: The effects of CS-088 on intraocular pressure (IOP) were studied in 2 models of rabbit ocular hypertension. Experimental ocular hypertension was induced in albino rabbits by injecting alpha-chymotrypsin into the anterior chamber (alpha-chymotrypsin rabbit). The effects of the single application of CS-088 were examined. Additionally, CS-088 was repeatedly administered over a period of 3 weeks to hereditary ocular hypertensive rabbits (buphthalmic rabbits, JWHR bu/bu) and the IOPs were monitored throughout the experiment. The effects of CS-088 on aqueous humor dynamics were also examined in normal rabbits. In this study, the methods of IOP recovery rate, two-level constant pressure perfusion and fluorescein-dextran perfusion were used respectively to determine the aqueous inflow, outflow facility and uveoscleral outflow (USF). RESULTS: CS-088 at 1% and 2% significantly lowered the IOP in the alpha-chymotrypsin rabbits with a maximum IOP reduction of 10.1 mmHg. The maximum effect obtained with 2% CS-088 was no greater than that with 1% CS-088. In the buphthalmic rabbits, 2% CS-088 also lowered IOP significantly. Timolol was effective in both models. In the study on aqueous humor dynamics, a slight increase in USF (17%) was seen after a topical application of CS-088 whereas changes in aqueous inflow or outflow facility were not observed. CONCLUSIONS: Topical CS-088 can decrease IOP in rabbits. Despite the USF change, the ocular hypotensive mechanism by CS-088 was not fully determined.

Administration, Topical↗
PubMed2001

Molecular cloning, characterization, and expression of porcine Fas ligand (CD95 ligand).

We isolated and sequenced cDNA that contained the coding sequence of porcine Fas ligand (FasL). Using mixed oligonucleotide primers based on the 5' and 3' nucleotide sequences conserved among human, murine, and rat FasL, we performed the reverse transcription polymerase chain reaction (RT-PCR) with total RNA prepared from porcine thymocytes stimulated with 5 microg/ml concanavalin A (ConA) to clone the cDNA of porcine FasL. The open reading frame (ORF) of porcine FasL cDNA was 849 base pairs (bp) in length and encoded 282 amino acids. The predicted amino acid sequence was 85.5%, 76.6%, and 75.5% homologous to the predicted human, murine, and rat FasL, respectively. The recombinant porcine FasL expressed by recombinant baculovirus containing the whole coding sequences of porcine FasL showed cytotoxic effect and induced apoptosis in porcine renal tubular cell line PK-15 cells sensitized by cycloheximide (CHX), which was confirmed by MTT assay, DNA fragmentation assay, and TUNEL staining, respectively. Furthermore, the mRNA expression of porcine FasL in porcine peripheral blood lymphocytes (PBL) was induced by porcine interleukin-18 (IL-18). These results indicate that porcine FasL identified in this study is biologically functional and has the ability to induce apoptosis as reported in other species.

Amino Acid Sequence↗
PubMed2001

Efficient production of biologically active porcine interleukin-18 by coexpression with porcine caspase-1 using a baculovirus expression system.

We previously reported that the precursor form of porcine interleukin-18 (IL-18) expressed by the baculovirus system was able to be secreted efficiently into the supernatant of insect cells, whereas only small amounts of mature IL-18 were secreted from insect cells. As insect cells do not normally have the IL-1beta converting enzyme (caspase-1), which is required for processing of the precursor IL-18 into the mature IL-18, we recently cloned porcine caspase-1 cDNA. In this study, we constructed a recombinant baculovirus containing the cDNA encoding porcine caspase-1 and showed that the coexpression of caspase-1 and the precursor IL-18 enabled insect cells to secrete mature IL-18 into the culture supernatant efficiently. Moreover, inhibition of caspase-1 activity by its specific inhibitor prevented the processing of precursor IL-18 into the mature form. These results indicated that the processing and secretion of precursor IL-18 into the mature form in insect cells were enhanced by the artificial introduction of caspase-1 activity for cleavage.

Animals↗
PubMed2001

Porcine caspase-3: its cloning and activity during apoptosis of PK15 cells induced by porcine Fas ligand.

We cloned and sequenced cDNA that contained the coding sequence of porcine caspase-3. The open reading frame (ORF) of porcine caspase-3 cDNA was 834 base pairs (bp) in length and encoded 277 amino acids. The predicted amino acid sequence was 88.4%, 86.6%, and 87.7% homologous to the predicted human, murine, and rat amino acid sequences, respectively. The activity of caspase-3 in porcine renal tubular cell line PK15 after recombinant porcine Fas ligand (FasL) stimulation was examined. The enzymatic activity of caspase-3, but not that of caspase-1, was significantly increased after FasL treatment. Western blot analysis also showed that the processing of caspase-3 from proenzyme to mature subunits occurred after FasL treatment. The inhibition of caspase-3 by its specific inhibitor partially prevented the apoptotic cell death of PK15 cells caused by FasL. The porcine caspase-3 cDNA isolated in this study will be useful for the study of apoptotic cell death in pigs and will lead to the discovery of therapeutic uses of caspases and their inhibitors in the prevention of viral and bacterial diseases and tissue injury associated with xenotransplantation and allotransplantation.

Amino Acid Sequence↗
PubMed2001

How to distinguish garlic from the other Allium vegetables.

The establishment of international monographs for herbs is in progress. Here, we propose both a marker compound and a method for its analysis for the identification of garlic bulbs and their products. The constituents in 26 kinds of fresh edible parts of Allium vegetables and three types of garlic preparations were analyzed. Sulfur compounds are the most characteristic constituents in garlic, but manufacturing processes of garlic products dramatically affect these constituents. Thus, no sulfur compound could be specified as a universal marker of identification applicable for any type of garlic. On the other hand, garlic contains other characteristic compounds, namely, saponins. After analyzing Allium vegetables and garlic preparations, we concluded that sapogenins, especially beta-chlorogenin, may be a viable candidate for identifying and distinguishing garlic from other Allium vegetables.

Allium↗
PubMed2001

Lack of change in the levels of liver and kidney cytochrome P-450 isozymes in p53+/- knockout mice treated with N-butyl-N-(4-hydroxybutyl)nitrosamine.

We have previously shown that p53(+/-) knockout mice are highly sensitive to urinary bladder carcinogenesis induced by N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) in spite of a lack of effects of p53 heterozygosity on N-butyl-N-(3-carboxypropyl)nitrosamine (BCPN) excretion in urine. To determine the influence of p53 deficiency on in vitro formation of BCPN, mutagenicity of BBN and BCPN and levels of several cytochrome P450 (CYP) isozymes, groups of five p53(+/-) knockout and wild-type mice (littermates), as well as animals of the C57BL/6 parental strain, were administered 0.025% BBN in their drinking water for 4 weeks. The livers and kidneys were then used for analyses of BBN metabolism, western immunoblotting and Ames liquid incubation. BBN treatment caused a slight decrease in BCPN formation in the livers of C57BL/6 mice, but there was no significant difference between p53 knockout, wild-type and C57BL/6 mice. In kidney BCPN formation in p53 knockout mice was 33-46% less than that in their wild-type counterparts. Using anti-rat CYP antibodies, CYP1A2, 2B9/10, 2E1 and 3A11/13 were constitutively detected in liver microsomes and CYP2E1 and 3A11/13 in the kidney. Densitometric determination of these CYP proteins revealed no significant variation in levels detected in both tissues among the four groups of mice. BBN and BCPN were not mutagenic for Salmonella typhimurium TA100 in either the absence or presence of liver S9 from untreated mice and rats and from p53 knockout mice treated with BBN. In conclusion, p53 deficiency and BBN had no enhancing effects on metabolism of BBN to BCPN and expression of the CYP isozymes typically responsible for activation of environmental carcinogens, including both of the N-nitrosamines tested, and their mutagenicity, indicating that the high susceptibility of p53(+/-) knockout mice is not attributable to metabolic activation in liver and kidney by CYP isozymes or urinary excretion of BCPN.

Animals↗
PubMed2001

N-benzylimidazole for preparation of S9 fraction with multi-induction of metabolizing enzymes in short-term genotoxicity assays.

To evaluate the usefulness of N-benzylimidazole (BI) as an inducer with wide spectrum detection of precarcinogens in short-term bioassays, hepatic levels of cytochrome P-450 (CYP) and mutagenic activation of various carcinogens in Wistar and Sprague-Dawley rats orally treated with BI and BI plus ethanol or acetone were compared with those in the same strains of rats treated with 3-methylcholanthrene (MC), phenobarbital (PB) and polychlorobiphenyls (PCB). Immunoblot analyses for microsomal CYP proteins revealed a marked induction by BI in the levels of CYP1A1, CYP2B1 and constitutive CYP1A2 (approximately 11-fold), 2B2 (approximately 21-fold), 2E1 (1.5-fold) and 3A2 (4-fold) in rats of both strains. These levels were comparable with those induced by MC and PB, but were less than the CYP1A1/2 and 2B1 levels induced by PCB, while CYP2B2 was at the same level. In contrast, the level of CYP2E1 was clearly higher in BI-treated rats. The combinations of BI and acetone or ethanol specifically induced CYP2E1 (4-fold) and 2B1 (1.7-fold) levels when compared with BI alone in Wistar rats. The combined treatments also elevated mutagenic activities of eight heterocyclic amines (HCAs), aflatoxin B(1) (AFB(1)), benzo[a]pyrene and 2-aminofluorene in strain TA98 up to 14.3-, 5.1-, 2.8- and 2.1-fold above the untreated group, respectively, and those of five N-nitrosamines in strain TA100 up to 19.1-fold. Induction of specific CYP species responsible for activation of HCAs, AFB(1) and N-nitrosamines was confirmed by application of several CYP inhibitors. In addition, BI induced activities of both MC- and PB-inducible UDP-glucuronyltransferases towards 4-nitrophenol and testosterone. These results demonstrate that BI has a bifunctional action, with wide spectrum induction of phase I and II enzymes, and combined treatment with ethanol or acetone would be a pertinent inducer for metabolic enzymes in in vitro bioassays, the potential being comparable with or superior to other typical ones.

Administration, Oral↗
PubMed2001

An accurate three-dimensional cephalometric system: a solution for the correction of cephalic malpositioning.

In recent years, methods have been developed that calculate three-dimensional (3D) co-ordinates of orthodontic landmarks from lateral and frontal cephalograms. However, precise measurement has been impossible with these methods because, although they corrected the magnification of the image, they did not correct 3D cephalic malpositioning that occurs during the measurement of human subjects. In this study, we developed a 3D cephalometric system that corrected not only for magnification of the image, but also 3D cephalic malpositioning during cephalogram exposure. Magnification of the image was corrected for first. Cephalic revolution was then sequentially corrected and divided into elements of x-, y-, and z-axes. The origin was parallelly translated to the mid-point of bilateral porion. In order to examine the accuracy of this system, seven human dry skulls were measured. The accuracy unaffected by the cephalic revolution in any direction and standard errors was within 0.8 mm in any orthodontic landmarks. It was suggested that this measurement system would have sufficient accuracy for clinical application. The results indicated that precise cephalometric measurement was possible with this system and it was suggested that its clinical application would be possible.

Algorithms↗
PubMed2001

The mouse putative pheromone receptor was specifically activated by stimulation with male mouse urine.

To detect the biological activity of mammalian putative pheromone receptors (V1Rs and V2Rs), the mouse V1R gene was introduced into a primary culture of vomeronasal cells using the adenovirus expression system, and the response of these cells to mouse urine was analyzed by calcium imaging. These cells specifically responded to male but not female mouse urine. This response was attenuated by pertussis toxin, a specific inhibitor of G-protein G(ialpha)/G(oalpha) coupling from receptors. Our findings indicate that a putative pheromone receptor was specifically activated by mouse urine, a major source of mouse pheromones, and suggest that G(i)/G(o) are functionally coupled with the receptor.

Amino Acid Sequence↗
PubMed2001

A study of apoptosis in Merkel cell carcinoma: an immunohistochemical, ultrastructural, DNA ladder, and TUNEL labeling study.

We performed immunohistochemical, ultrastructural, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL), and DNA ladder studies of apoptosis in nine cases of Merkel cell carcinoma (MCC). None of the cases showed spontaneous regression as has been reported in several MCCs. Neuron-specific enolase was demonstrated by immunohistochemistry (8/8 MCCs), and staining for cytokeratin 20 was positive (2/8 MCCs). Ultrastructural examination revealed many cytoplasmic dense-cored granules, desmosome-like structures, and intermediate filaments. The granules were seen along the plasma membrane or around perinuclear centrioles. We found various stages of development of apoptotic bodies. Apoptosis resulted in vacuolization and fragmentation of nuclei and phagocytosed bodies in tumor cells. Apoptotic cells were also detected by TUNEL, DNA ladder, and immunostaining using the antibody against Fas (Apo- 1/CD95) antigen. It seems that a high apoptotic rate is a common finding in MCC, although spontaneous regression is an exceedingly rare event. It is thus unlikely that apoptosis alone would explain spontaneous regression.

Aged↗
PubMed2001

Celiprolol stimulates endothelial nitric oxide synthase expression and improves myocardial remodeling in deoxycorticosterone acetate-salt hypertensive rats.

OBJECTIVE: Endothelium-dependent vasodilation is attenuated in humans and experimental hypertension models, and this phenomenon may be largely due to decreased release or activity of nitric oxide (NO). However, very few studies have evaluated whether beta-adrenoceptor antagonists increase endothelial NO synthase (eNOS) expression in the left ventricle. We examined the effects of long-term treatment with celiprolol, a specific beta1-antagonist with a weak beta2-agonist action, on eNOS expression in the left ventricle and evaluated its relationship to myocardial remodeling in the left ventricle of deoxycorticosterone acetate (DOCA)-salt hypertensive rats. METHODS: DOCA-salt rats (n = 18) were induced with weekly injections of DOCA (30 mg/kg) and 1% saline in their drinking water after right nephrectomy. Celiprolol (DOCA-CEL, n = 9, 10 mg/kg per day, subdepressor dose) or a vehicle (DOCA-V, n = 9) were given after induction of DOCA-salt hypertension for 5 weeks, and age-matched sham-operated rats (ShC, n = 9) served as a control group. RESULTS: Blood pressure levels in DOCA-V and DOCA-CEL were similar and significantly higher than that in ShC. The eNOS mRNA and protein levels, and NOS activity in the left ventricle significantly decreased in DOCA-V compared with ShC, and significantly increased in DOCA-CEL compared with DOCA-V. DOCA-V showed a significant increase in the wall-to-lumen ratio, perivascular fibrosis, myocardial fibrosis, and type I collagen mRNA, with all these parameters being significantly improved by celiprolol. CONCLUSIONS: Myocardial remodeling of DOCA-salt hypertensive rats was significantly ameliorated by subdepressor doses of celiprolol, which may be due to increased eNOS expression in the left ventricle.

Adrenergic beta-Antagonists↗
PubMed2001

Activation of inositol 1,4,5-trisphosphate receptor is essential for the opening of mouse TRP5 channels.

We studied the opening mechanism of Ca(2+)-permeable channels formed with mouse transient receptor potential type 5 (mTRP5) using Xenopus oocytes. After stimulation of coexpressed muscarinic M(1) receptors with acetylcholine (ACh) in a Ca(2+)-free solution, switching to 2 mM Ca(2+)-containing solution evoked a large Cl(-) current, which reflects the opening of endogenous Ca(2+)-dependent Cl(-) channels following Ca(2+) entry through the expressed channels. The ACh-evoked response was not affected by a depletion of Ca(2+) store with thapsigargin but was inhibited by preinjection of antisense oligodeoxynucleotides (ODNs) to G(q), G(11), or both. The mTRP5 channel response was also induced by a direct activation of G proteins with injection of guanosine 5'-3-O-(thio)triphosphate (GTP gamma S). The ACh- and GTP gamma S-evoked responses were inhibited by either pretreatment with a phospholipase C inhibitor, U73122, or an inositol-1,4,5-trisphosphate (IP(3)) receptor inhibitor, xestospongin C (XeC). An activation of IP(3) receptors with injection of adenophostin A (AdA) evoked the mTRP5 channel response in a dose-dependent manner. The AdA-evoked response was not suppressed by preinjection of antisense ODNs to G(q/11) or U73122 but was suppressed by either preinjection of XeC or a peptide mimicking the IP(3) binding domain of Xenopus IP(3) receptor. These findings suggest that the activation of IP(3) receptor is essential for the opening of mTRP5 channels, and that neither G proteins, phosphoinositide metabolism, nor depletion of the Ca(2+) store directly modifies the IP(3) receptor-linked opening of mTRP5 channels.

Acetylcholine↗
PubMed2001

Distribution and diversity of symbiotic thermophiles, Symbiobacterium thermophilum and related bacteria, in natural environments.

Symbiobacterium thermophilum is a tryptophanase-positive thermophile which shows normal growth only in coculture with its supporting bacteria. Analysis of the 16S rRNA gene (rDNA) indicated that the bacterium belongs to a novel phylogenetic branch at the outermost position of the gram-positive bacterial group without clustering to any other known genus. Here we describe the distribution and diversity of S. thermophilum and related bacteria in the environment. Thermostable tryptophanase activity and amplification of the specific 16S rDNA fragment were effectively employed to detect the presence of Symbiobacterium. Enrichment with kanamycin raised detection sensitivity. Mixed cultures of thermophiles containing Symbiobacterium species were frequently obtained from compost, soil, animal feces, and contents in the intestinal tracts, as well as feeds. Phylogenetic analysis and denaturing gradient gel electrophoresis of the specific 16S rDNA amplicons revealed a diversity of this group of bacteria in the environment.

Animals↗