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T Tsuboi

Publications and source records attributed to T Tsuboi.

At least 55 records · Page 3Linked to original sources
PubMed1998

Optical rotation signals recorded from a single skeletal muscle fibre of a frog.

The optical rotation signal of a single frog skeletal muscle fibre was recorded and its properties were examined. To reduce movement of the fibre associated with its excitation, fibre was immersed in Ringer solution made of 90-95% D2O, stretched, and lightly pressed from above with a cylindrical lens. After these procedures no mechanical movements were recognizable under the dissection microscope, and the optical rotation signal appeared consistently as a brief transient increase in dextrorotation with a duration of about 23 ms. The shape and polarity of the signal did not change among preparations and remained unchanged when the direction of impulse conduction along the fibre was reversed. The influence of the birefringence change associated with excitation was found to be small in most preparations. Ryanodine (10 micron) reduced the amplitude of the signal to about half that of the control, and increased the duration slightly. Nitrendipine (10 micron) reduced the duration of the signal to about half that of the control, and reduced the amplitude to about two-thirds of the control. The effects of the chemicals took place within 10 minutes and remained constant for the periods examined. The intracellular action potentials were not appreciably altered by these chemicals. It is concluded that the optical rotation signal of the single muscle fibre reports the molecular conformational change of proteins during the early stage of the contraction process.

Animals↗
PubMed1998

The nocturnal secretion of cardiac natriuretic peptides during obstructive sleep apnoea and its response to therapy with nasal continuous positive airway pressure.

The nocturnal secretion profile of the newly identified natriuretic peptide (NP), brain natriuretic peptide (BNP), was studied in 14 patients with obstructive sleep apnoea syndrome (OSAS) (apnoea hypopnoea index: 60.5 +/- 3.4, mean +/- SE) during two separate nights before and during nasal continuous positive airway pressure (NCPAP) therapy. Plasma levels of NPs (atrial natriuretic peptides; ANP and BNP) were measured at 2-h intervals during sleep. Simultaneously, blood pressure was measured by a non-invasive method (Finapres, Ohmeda, Englewood, CO, USA) and urine was collected for determining volume and catecholamine levels. Urinary and serum sodium concentration were determined before and after the study. Eight non-snoring subjects were also studied for the investigation of normal nocturnal profiles of BNP levels. To understand the discrete secretion profiles of the two NPs during sleep, blood was sampled from an additional seven patients every 5 min over a 30-min period around 00.00 and 04.00 hours before NCPAP. In patients with OSAS, plasma BNP levels increased from the beginning of sleep (22:00 h) to the morning (06:00 h) before NCPAP therapy (P < 0.01, ANOVA). Baseline BNP levels were not significantly correlated with patient's clinical and polysomnographic parameters. However, in the latter half of the sleep period (02:00-06:00 h), increases in BNP levels during the night before NCPAP therapy were significantly correlated with blood pressure elevations (systolic: r = 0.784 P < 0.01, diastolic: r = 0.587 P < 0.01) and with apnoea duration (r = 0.582 P < 0.01). In normal subjects BP and BNP levels were not changed significantly during sleep. Plasma BNP levels were well correlated with concomitant ANP levels (P < 0.001). NCPAP therapy reduced ANP and BNP levels during sleep and in the morning (P < 0.01). Plasma levels of BNP at 5 min intervals before NCPAP therapy revealed few variations. On the other hand, ANP levels fluctuated over the 30-min period. Changes in BNP levels during sleep in the patients with OSAS may be related to blood pressure variations, but may be too small to play a significant physiological role in regulating diuresis in OSAS. Further work is required to determine the precise role of dual natriuretic system in cardiovascular load and natriuresis in OSAS.

Atrial Natriuretic Factor↗
PubMed1998

Improvement of factor VII clotting activity following long-term NCPAP treatment in obstructive sleep apnoea syndrome.

Obstructive sleep apnoea syndrome (OSAS) is a very common disorder. Patients with OSAS are at an increased risk for cardiovascular events. It has also been reported that a 25% rise in factor VII clotting activity (FVIIc) is associated with a 55% increase in ischaemic heart disease death during the first 5 years. We examined the effects of nasal continuous positive airway pressure (NCPAP) treatment on FVIIc in patients with OSAS. FVIIc was investigated prospectively in 15 patients with OSAS before (mean +/- SEM apnoea and hypopnoea index (AHI) 61.5 +/- 4.2 and after (AHI 3.0 +/- 0.9) NCPAP treatment for immediate relief, at 1 month after treatment and at over 6 months. FVIIc levels gradually decreased after NCPAP treatment. After 6 months of NCPAP treatment, FVIIc levels had decreased significantly (before 141.1 +/- 11.7% vs. after 6 months 110.7 +/- 6.2%; p < 0.01). Six of the seven patients whose FVIIc levels were over 140% before the NCPAP treatment had FVIIc levels below 130% after 6 months or 1 year of NCPAP treatment. This decrease in FVIIc after long-term NCPAP treatment could improve mortality in OSAS patients. If patients, especially obese ones, present with high FVIIc of unknown origin, it would be prudent to check for OSAS.

Adult↗
PubMed1998

Enhanced melanogenesis induced by tyrosinase gene-transfer increases boron-uptake and killing effect of boron neutron capture therapy for amelanotic melanoma.

Specific and powerful cancer killing effect for melanoma by boron neutron capture therapy (BNCT) using DOPA analogue, 10B-p-boronophenylalanine (10B-BPA), has been established, but amelanotic melanoma is insufficiently responsive to 10B-BPA BNCT in comparison with actively melanin-producing melanoma. Although the accumulation mechanism of 10B-BPA within melanoma was not established, we have recently obtained findings suggesting that melanin monomers, key intermediates for melanin polymer formation, play a critical role in 10B-BPA accumulation. In addition, there are some kinds of human amelanotic melanomas, such as MEL2A, in which expression of tyrosinase is repressed or lacking though tyrosinase-related protein (TRP)-1 and TRP-2 are well expressed. Thus, by using a similarly tyrosinase-lacking mouse amelanotic melanoma cell line, A1059, we constructed TA1059 cells by transfecting human tyrosinase-cDNA into these cells. TA1059 cells acquired higher DOPA-oxidase and DOPAchrome tautomerase activity as well as eumelanin content at even higher levels than those of B16F10 cells. TA1059 cells showed about 2.5 times higher P-boronophenylalanine (BPA) uptake than A1059 cells in culture. In animal experiments, by using these cell lines, tumor growth of TA1059 was significantly suppressed by 10B-BPA BNCT as compared with A1059. These findings indicate that the induction of active melanin biosynthesis by melanogenic gene-transfer effectively improves the treatment of amelanotic melanoma by BNCT.

Animals↗
PubMed1998

Bovine viral diarrhea virus replication in bovine follicular epithelial cells derived from persistently infected heifers.

Bovine follicle fluid and oocytes surrounded by follicular epithelial (FE) cells were collected from ovaries of two heifers persistently infected with bovine viral diarrhea virus (BVDV). BVDV was present in the follicle fluid at a higher titer than in serum. The oocytes were matured in vitro under culture conditions of 39 degrees C in humidified air containing 5% CO2. In vitro fertilization was performed after 24 hr in culture (the day of insemination was defined as day 1), and culture was continued through day 10. BVDV was present in the culture medium at titers of 10(2.25) to 10(3.25) TC(I)D50/0.1 ml. The virus was also detected in FE cells collected on day 10. Viral antigen was demonstrated in the cytoplasm of FE cells by the indirect immunofluorescence technique. However, no BVDV was detected in the embryos on day 10. These findings suggested that the oocytes or embryos were unlikely to be infected with BVDV, but that the FE cells were infected with BVDV and supported virus replication in cattle persistently infected with BVDV.

Animals↗
PubMed1998

Effects of nasal continuous positive airway pressure therapy on respiratory parameters of upper airway patency in patients with obstructive sleep apnea syndrome.

OBJECTIVES: To assess whether an initial treatment with nasal continuous positive airway pressure (NCPAP) therapy, applied for one night, had any effect on airway patency. METHODS: In 18 patients with obstructive sleep apnea syndrome (OSAS), we measured the total resistance of the respiratory system (Rrs) and their relevant lung functions before and after polysomnography, with and without NCPAP therapy. The Rrs was measured at 3 Hz with the forced oscillation technique. The overnight changes in the specific respiratory conductance (SGrs=reciprocal of the Rrs per unit lung volume) was also calculated in the sitting position. Since many reports have suggested that obesity, through fat deposits around the pharynx, can affect the mechanical and neuromuscular properties of the upper airway, we also investigated if the degree of obesity was related to the magnitude of improvement in these parameters. RESULTS: After the first night of NCPAP therapy, the Rrs decreased (sitting: 4.8+/-0.4 vs 4.3+/-0.4 cm H20/L/s, p < 0.05; lying: 6.5+/-0.4 vs 5.6+/-0.4 cm H20/L/s, p < 0.05) and the maximal voluntary ventilation increased in the morning (sitting: 101.6+/-5.8% vs 106.4+/-4.5%, p < 0.05; lying: 91.2+/-5.4% vs 97.9+/-4.7%, p < 0.05). The overnight difference in the SGrs showed a significant improvement after the initial treatment with NCPAP therapy (p < 0.05). However, the lung volume, flow volume loop, and closing volume in the morning did not change significantly after the therapy. An overnight decrease in the Rrs following NCPAP therapy is significantly correlated with the body mass index (sitting: r=0.54, p < 0.05; lying: r=0.61, p < 0.01). CONCLUSION: The improvements in Rrs without changes in spirometry may reflect improved upper airway patency after NCPAP therapy. The degree of obesity is suggested to be associated with the treatment effect on upper airway in patients with OSAS.

Adult↗
PubMed1998

Involvement of vitamin D in lead-induced cutaneous calcification in rodents.

Experimental cutaneous calcification was induced by a subcutaneous injection of lead acetate in parathyroidectomized (PTX) rats and vitamin D-deficient rats whose plasma calcium concentrations were controlled by diets containing various amounts of calcium. Although, in PTX rats, the calcium content of the calcified plaque induced by lead acetate was correlated with their plasma calcium concentration, calcium content of the calcified plaque in vitamin D-deficient rats with normocalcemia was significantly lower than those in control and PTX rats with normocalcemia. A subcutaneous administration of 1 alpha,25-dihydroxyvitamin D3 (1 alpha,25(OH)2D3) following the lead acetate injection increased calcium content of the calcified plaque in vitamin D-deficient mice, suggesting the involvement of vitamin D in the cutaneous calcification. As the synthesis of osteocalcin, osteopontin and interleukin-1 (IL-1) receptor is well known to be increased by 1 alpha,25(OH)2D3, gene expressions of mRNAs of these proteins were examined in the skin with calcified plaque by reverse transcription polymerase chain reaction (RT-PCR) analysis. These mRNA expressions in the skin with calcified plaque were increased by a subcutaneous administration of 1 alpha,25(OH)2D3 following the lead acetate injection. On the contrary, they decreased in vitamin D-deficient mice. These findings suggest that vitamin D is directly involved in the process of experimental calcification.

Animals↗
PubMed1998

[Report of national survey on death due to tuberculosis in 1994 in national hospitals and the treatment and prognosis of tuberculous patients with mechanical ventilation].

1. National survey on died patients with active tuberculosis (tbc) or tbc sequelae had been held in national hospitals every five year from 1959 (3433 cases) to 1994 (688 cases). In 1994, 330 patients died due to pulmonary tbc. Recent study revealed the decreased rate of death due to operation, or far advanced cavitary cases, and the increased rate of nontuberculous death, aged people (> 60 yrs), and nontuberculous complications. Main causes of death in pulmonary tbc were lung insufficiency (about half) and general weakness (almost one fifth) in any survey. Rapid progression of pulmonary tbc had been increased cause of death (20.9% in 1994). Main attributable factors of death in 1994 in pulmonary tbc cases were severe condition on admission (38.4%), disturbed lung function (31.2%) and old age (33.2%). Delayed treatment (13.9%) and complications (12.1%) were increasing factors. Early death within 3 months from onset in 1994 was seen in patients < 60 yrs as well as in patients > 80 yrs. Severity due to delayed treatment and rapid progression were supposed to the causes of early death. 2. During 1994 to 1997, mechanical ventilation (MV; > 24 hours) was applied to 18 patients with active pulmonary tuberculosis; 10 acute respiratory failure (ARF), 5 chronic respiratory failure (CRF), 2 central nervous system tbc and 1 hemoptysis. Only one ARF case and three CRF ones survived. ARF cases had low PaO2/FIO2 (about 100), low albuminemia, short MV period (7 cases: < 7 days) and steroid therapy (9 cases). CRF cases had higher PaO2/FIO2 (294), longer MV period (4 cases: > 30 days) and all CO2 narcosis. 3. Noninvasive positive pressure ventilation (NIPPV) was applied to 23 patients with pulmonary tbc sequelae. In 13 patients with stable chronic respiratory failure (mean PaO2 91 mmHg, PaCO2 82 mmHg) 10 continued NIPPV and started home mechanical ventilation (HMV). In 10 patients with acute on chronic respiratory failure (mean PaO2 61 mmHg, PaCO2 92 mmHg) 2 patients fell into tracheal intermittent positive pressure ventilation (TIPPV). Eight patients recovered with NIPPV and 5 started HMV. NIPPV is supposed to be very effective to treat severe chronic hypercapmic respiratory failure.

Adult↗
PubMed1998

Sequence polymorphism in two novel Plasmodium vivax ookinete surface proteins, Pvs25 and Pvs28, that are malaria transmission-blocking vaccine candidates.

BACKGROUND: For many malarious regions outside of Africa, development of effective transmission-blocking vaccines will require coverage against both Plasmodium falciparum and P. vivax. Work on P. vivax transmission-blocking vaccines has been hampered by the inability to clone the vaccine candidate genes from this parasite. MATERIALS AND METHODS: To search for genes encoding the ookinete surface proteins from P. vivax, the DNA sequences of the eight known proteins in the P25 subfamily (Pfs25, Pgs25, Pys25, Pbs25) and in the P21/28 subfamily (Pfs28, Pgs28, Pys21, Pbs21) of zygote/ookinete surface proteins were aligned. Regions of highest identity were used to design degenerate PCR oligonucleotides. Genomic DNA from the Sal I strain of P. vivax and genomic and splinkerette DNA libraries were used as PCR templates. To characterize the polymorphisms of Pvs25 and Pvs28, these two genes were PCR amplified and the DNA sequences were determined from genomic DNA extracted from patients infected with P. vivax. RESULTS: Analysis of the deduced amino acid sequence of Pvs28 revealed a secretory signal sequence, four epidermal growth factor (EGF)-like domains, six copies of the heptad amino acid repeat (GSGGE/D), and a short hydrophobic region. Because the fourth EGF-like domain has four rather than six cysteines, the gene designated Pvs28 is the presumed homologue of P21/28 subfamily members. Analysis of the deduced amino acid sequence of Pvs25 revealed a similar structure to that of Pvs28. The presence of six rather than four cysteines in the fourth EGF-like domain suggested that Pvs25 is the homologue of P25 subfamily members. Several regions of genetic polymorphisms in Pvs25 and Pvs28 were identified in field isolates of P. vivax. CONCLUSIONS: The genes encoding two ookinete surface proteins, Pvs28 and Pvs25, from P. vivax have been isolated and sequenced. Comparison of the primary structures of Pvs25, Pvs28, Pfs25, and Pfs28 suggest that there are regions of genetic polymorphism in the P25 and P21/28 subfamilies.

Amino Acid Sequence↗
PubMed1997

Effect of bovine herpes virus-1, bluetongue virus and akabane virus on the in vitro development of bovine embryos.

Bovine oocytes enclosed by follicular epithelial (FE) cells were exposed to bovine herpes virus-1 (BHV-1), bluetongue virus (BTV) and akabane virus (AV), matured in culture for 24 h and then in vitro fertilized. In the BHV-1-exposed group, BHV-1 was isolated from medium 3 days after in vitro fertilization at a high titer, and a severe cytopathic effect was observed in the FE cells. Oocytes in the BHV-1-exposed group developed to the 2-cell to 8-cell stage, but failed to develop into blastocysts. In the BTV-exposed group, BTV replication was observed in the FE cells during in vitro embryo development into blastocysts. In the AV-exposed group, no distinct AV replication was detected in FE cells during in vitro embryo development. These results indicate that these viruses failed to infect zona-intact oocytes or embryos during in vitro maturation and culture.

Animals↗
PubMed1997

Two antigens on zygotes and ookinetes of Plasmodium yoelii and Plasmodium berghei that are distinct targets of transmission-blocking immunity.

We have developed transmission-blocking monoclonal antibodies (MAbs) against Plasmodium yoelii 21-kDa (Pys21) and 28-kDa (Pys25) ookinete surface proteins. These MAbs block infectivity of P. yoelii to Anopheles stephensi. One MAb, 14, cross-reacted by Western blotting with a 28-kDa surface protein (Pbs25) of P. berghei ookinetes and blocked oocyst development, as assayed by direct mosquito feeds on passively immunized P. berghei-infected mice. In total, we have identified two ookinete surface proteins in P. yoelii, one of which is also present in P. berghei. The transmission-blocking activity of the anti-Pys25 MAb 4 was complete and more potent than that of the anti-Pys21 MAb 2. Moreover, Fab fragments of MAb 4 had transmission-blocking activity in mice. In comparison, Fab fragments of MAb 2 did not have detectable transmission-blocking effect, although F(ab')2 did. Furthermore, MAb 2 and MAb 4 appeared to block the in vitro formation and development of zygotes as well.

Animals↗
PubMed1997

Heat shock protein 72 level decreases during sleep in patients with obstructive sleep apnea syndrome.

Patients with obstructive sleep apnea syndrome (OSAS) suffer from stresses related to repetitive apneas during sleep. To examine whether the level of 72 kDa heat shock protein (HSP72) increases during sleep, 11 OSAS patients (apnea-hypopnea index: 63.5 +/- 36.1, mean +/- SD) underwent polysomnography and their peripheral blood mononuclear cells (PBMC) were isolated before, during, and after sleep. HSP72 level was determined by Western blotting and hsp72 mRNA level was quantified by Northern blotting. Nine normal subjects without OSAS were examined as normal controls. HSP72 level decreased progressively during sleep and its level at 8:00 A.M. was 78.0 +/- 17.5% of that at 8:00 P.M. (p < 0.01). No such decrease was seen in normal subjects. When OSAS patients received nasal continuous positive airway pressure (NCPAP) therapy, HSP72 level did not decrease significantly. In untreated OSAS patients, hsp72 mRNA level decreased during sleep (p < 0.01). When OSAS patients were treated with NCPAP therapy, the decrease in hsp72 mRNA level was not observed. HSP72 level before sleep in OSAS patients was higher than that in normal subjects (p < 0.01). We concluded that repetitive apneas caused high HSP72 level before sleep in OSAS patients and that NCPAP therapy had significant effect on HSP72 levels during sleep.

Blotting, Northern↗
PubMed1997

Ventilatory support during exercise in patients with pulmonary tuberculosis sequelae.

STUDY OBJECTIVE: The aim of this study was to determine whether intermittent positive pressure ventilation through a nasal mask (NIPPV) applied during exercise in patients with pulmonary tuberculosis sequelae (PTS) could improve arterial blood gas measurements, ameliorate breathlessness, and increase exercise endurance. PATIENTS: Seven PTS patients with a severe restrictive ventilatory defect (mean [SD] vital capacity, 1.02 [0.25] I) enrolled in this study had experienced NIPPV previously, and were familiar with the procedure. DESIGN: The patients underwent four constant-load cycle ergometer tests in the supine position to tolerance. The tests were performed with and without NIPPV, while breathing normoxic air (Air) or supplemental oxygen (O2; 35%). NIPPV was delivered during exercise in a controlled, volume-cycled mechanical ventilation mode, and the ventilator settings were modulated manually to meet patients' respiratory demands as estimated from the airway pressure waveform and the patient's breathlessness. RESULTS: All patients matched their breathing to the ventilator cycle during most of the exercise while receiving NIPPV. NIPPV significantly prolonged their exercise endurance time, from a mean (SD) of 180 (58) s to 310 (96) s in Air, and from 227 (64) s to 465 (201) s in O2. During exercise, NIPPV effectively decreased their breathlessness and significantly improved arterial blood gas measurements. CONCLUSIONS: NIPPV applied during exercise can effectively support ventilation, significantly ameliorate breathlessness, and consequently improve exercise endurance in patients with PTS.

Aged↗
PubMed1997

Molecular cloning of the human UMP synthase gene and characterization of point mutations in two hereditary orotic aciduria families.

Uridine monophosphate (UMP) synthase is a bifunctional enzyme catalyzing the last two steps of de novo pyrimidine biosynthesis, orotate phosphoribosyltransferase (OPRT) and orotidine-5'-monophosphate decarboxylase (ODC). Loss of either enzymatic activity results in hereditary orotic aciduria, a rare autosomal recessive disorder characterized by retarded growth, anemia, and excessive urinary excretion of orotic acid. We have isolated the UMP synthase chromosomal gene from a lambdaEMBL-3 human genomic library and report a single-copy gene spanning approximately 15 kb. The UMP synthase genomic structure encodes six exons ranging in size from 115 bp to 672 bp, and all splicing junctions adhere to the canonical GT/AG rule. Cognate promoter elements implicated in glucocorticoid- and cAMP-mediated regulation as well as in liver-, myeloid-, and lymphocyte-specific expression are located within the 5' flanking sequence. Molecular investigation of UMP synthase deficiency in a Japanese orotic aciduria patient revealed mutations R96G (A-to-G transition; nt 286) and G429R (G-to-C transversion; nt 1285) in one allele and V109G (T-to-G transversion; nt 326) in the other allele. Expression of human UMP synthase cDNAs containing these mutations in pyrimidine auxotrophic Escherichia coli and in recombinant baculovirus-infected Sf21 cells demonstrates impaired activity presumably associated with the urinary orotic acid substrate accumulations observed in vivo. We further establish the identity of two polymorphisms, G213A (v = .26) and 440Gpoly (v = .27) located in exons 3 and 6, respectively, which did not significantly compromise either OPRT or ODC function.

Adult↗
PubMed1996

Plasmodium vivax: favored gene frequencies of the merozoite surface protein-1 and the multiplicity of infection in a malaria endemic region.

In this study, we present an analysis of the Plasmodium vivax MSP-1 polymorphic region 5 and identify a new recombinant gene element. In clinical isolates from Papua New Guinea (PNG), the P. vivax MSP-1 gene type was characterized by restriction fragment length polymorphisms and by Southern blot oligonucleotide hybridizations using probes to type-specific sequences. There were three pairs of dimorphic gene elements in the MSP-1 polymorphic region 5; four of the eight potential different combinations of sequence elements for this region have been identified. The center gene segment was the most polymorphic, especially for the glutamine (Q) repeat element with virtually every gene containing a different length of Q repeats, a finding consistent with database sequence information. The frequencies of all of the polymorphic MSP-1 gene elements were approximately equal except for the first segment, which was biased 10:1 for the Type II (Sal-1 type) versus Type I (Belem type) gene segment. In fact, only one combination (I/Q/S) of the genetic elements containing the type I gene segment for polymorphic region 5 was identified, a finding consistent with sequences reported to gene data banks. Considering only the multiplicity of MSP-1 gene types, 38% of the patients were identified as having multiple infections; when correlated with the circumsporozoite protein and the Duffy antigen binding protein gene types, the multiple infection rate increased to 65% of 23 isolates characterized. Increased age was the only clinical parameter that positively correlated with multiclonal infections and there was no other apparent bias or linkage of gene types among the three loci. These data identify multiple clonal populations of P. vivax in the PNG population and potentially a high rate of concurrent infections in clinical cases. The extreme polymorphism of the MSP-1 polymorphic region 5 suggests that frequent recombination occurs within this gene. The bias in frequency for one recombinant gene motif indicates that intrinsic host or parasite factors may engender increased frequency of one genetic element over another. Failure to identify this type of discrete clonal marker as well as reliance on a single marker can mask the true multiclonal nature of an infection and lead to underestimation of the multiplicity of infection.

Amino Acid Sequence↗
PubMed1996

Noncytopathogenic and cytopathogenic bovine viral diarrhea-mucosal disease viruses do not affect in vitro embryonic development into the blastocyst stage.

Bovine oocytes enclosed within follicular epithelial (FE) cells were exposed to noncytopathogenic or cytopathogenic strains of bovine viral diarrhea-mucosal disease virus (BVD-MDV). After culture at 39 degrees C in humidified air with 5 percent CO2 for 24 h, the oocytes matured and then in vitro fertilization was performed. Some of the fertilized oocytes developed into blastocysts from day 8 to day 10 (day 1: date of insemination), and the rate of development to blastocysts was the same as for the unexposed control oocytes. In the developmental medium, each strain of BVD-MDV was present at 10(3) to 10(6) TCID (50)/0.25 ml from day 3 to day 10, respectively and the virus was isolated from the FE cells at high titers and from the embryos at low titers on day 10. BVD-MDV antigen was detected in the cytoplasm of the FE cells by indirect immunofluorescence. These findings indicate that BVD-MDV replicates well in FE cells. The results of this study suggest that BVD-MDV replication in cells around embryos has no effect on bovine embryo development.

Animals↗