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Biomedical subjects

N Kawate

Publications and source records attributed to N Kawate.

At least 19 recordsLinked to original sources

Lactoferrin expression in the canine uterus during the estrous cycle and with pyometra.

The expression of lactoferrin, a non-specific antimicrobial defence, in the canine uterus during the normal estrous cycle and in bitches with pyometra was examined. Using polymerase chain reaction analysis, lactoferrin gene transcripts were detected in the endometrium at all stages of the estrous cycle, with the highest levels in estrus. In normal bitches, endometrial lactoferrin mRNA increased from proestrus to estrus (P<0.05). Thereafter, it dramatically decreased from estrus to Day 10 of diestrus (P<0.05), and stayed low at Day 35 of diestrus and anestrus; this was consistent with blood estrogen concentrations. Levels of lactoferrin mRNA were higher in bitches with pyometra than in normal diestrus (P<0.05). With immunohistochemistry, distinct staining of lactoferrin was detected in the luminal and glandular epithelial cells of the endometrium at proestrus and estrus, but little staining was detected at Day 10 of diestrus. At Day 35 of diestrus and anestrus, a partial and weak reaction was present in the same region. In bitches with pyometra, the glandular epithelial cells and many cells in the uterine stroma were strongly stained. Staining cells in the stroma were morphologically similar to neutrophils. No lactoferrin staining was seen in the uterine stromal cells or myometrium in any section. These results suggest that, in the canine uterus, lactoferrin expression is related to the blood concentration of estrogen, and that the dramatic reduction in lactoferrin observed at the early stage of diestrus may impair antimicrobial defense. Also, enhanced expression of lactoferrin mRNA in the endometrium with pyometra may be associated with neutrophil invasion into the uterus to combat the infection.

Amino Acid Sequence↗

Effect of co-culturing with embryonic fibroblasts on IVM, IVF and IVC of canine oocytes.

We studied the effects of mouse embryonic fibroblasts (MEF) and canine embryonic fibroblasts (CEF) on IVM, IVF and IVC of canine oocytes. Cumulus-oocyte complexes were harvested from ovaries by slicing, and in vitro maturation was evaluated in three different conditions: culture media only (control), co-culture with MEF, or co-culture with CEF. The oocytes were cultured for 48 or 72 h. Only oocytes larger than 100 microm in diameter with a homogeneous dark cytoplasm and two or more layers of cumulus cells were used. The culture medium was TCM 199+10% fetal bovine serum (FBS) with 100 IU/mL penicillin and 100 microg/mL streptomycin. After 48 h of IVM, the oocytes were fertilized in vitro with fresh canine spermatozoa that had been selected by a swim-up method, and the oocytes and spermatozoa were co-cultured in modified Krebs-Ringer bicarbonate solution (TYH) for up to 20 h in 5% CO2 in air at 38.5 degrees C. After insemination, oocytes were transferred to three different conditions (the same as for IVM) and were cultured. After 48 or 72 h of maturation in vitro, the maturation rate of MII oocytes cultured in co-culture of MEF and CEF was higher than for oocytes cultured in control (P<0.05). Although the rate that reached the MII stage was not different in the 48 and 72 h cultures, the percentage of degenerated oocytes was greater at 72 h in all three treatment groups. The proportion of monospermic and polyspermic oocytes was not different among the three treatment groups. Cleavage rates were higher in the MEF and CEF treatment groups than in the control group (P<0.05). Co-culture with CEF developed the embryo up to the 16-cell stage, and with MEF up to morula stage. In conclusion, co-culture of embryonic fibroblast cells enhanced nuclear and cytoplasmic maturation of canine oocytes.

Animals↗

Preventive effects of CIDR-based protocols on premature ovulation before timed-AI in Ovsynch in cycling beef cows.

Ovsynch is a program developed to synchronize ovulation for timed breeding. In this paper, the authors investigate whether controlled internal drug release (CIDR)-based protocols prevent premature ovulation before timed-artificial insemination (AI) when Ovsynch is started a few days before luteolysis in cycling beef cows. Nine beef cows at 16 days after oestrus were treated with (1) Ovsynch, i.e. gonadotropin releasing hormone (GnRH) analogue on day 0, prostaglandin (PG) F(2alpha) analogue on day 7 and GnRH analogue on day 9 with timed-AI on day 10, (n=3); (2) Ovsynch+CIDR (Ovsynch protocol plus a CIDR for 7 days from day 0, n=3), or (3) oestradiol benzoate (OB)+CIDR+GnRH (OB on day 0 in lieu of the first GnRH treatment, followed by the Ovsynch+CIDR protocol, n=3). In the Ovsynch group (1) plasma progesterone concentrations fell below 0.5 ng/mL earlier (day 5) than in both CIDR-treated groups (2) and (3), where this occurred on day 8. Plasma oestradiol-17beta concentrations peaked on day 8 in the Ovsynch group and on day 9 in both CIDR-treated groups. The dominant follicle ovulated on day 10 in the Ovsynch group and on day 11 in both CIDR-treated groups. Thus, both CIDR-based protocols prevented premature ovulation before timed-AI in Ovsynch when the protocol was started a few days before luteolysis. This reflects the fact that progesterone levels remained high until the beef cattle were treated with PGF(2alpha).

Administration, Intravaginal↗

Reduction of mucin-1 gene expression associated with increased Escherichia coli adherence in the canine uterus in the early stage of dioestrus.

The relation between adherence of Escherichia coli and expression of mucin-1 (Muc1: an integral membrane mucin) mRNA in the endometrium was studied in beagle bitches at different stages of the oestrous cycle and in those with cystic endometrial hyperplasia/pyometra complex (pyometra). The number of E. coli adhering to the endometrium was low at pro-oestrus and oestrus and increased at the early stage (day 10) of dioestrus, corresponding to the implantation period; it declined thereafter. Adhesion of the organisms to endometrial epithelial cells collected at day 10 of dioestrus was inhibited by the addition of D-mannose. When endometrial epithelial cells collected at pro-oestrus were treated with hyaluronidase, an enzyme that digests mucins, the numbers of E. coli adhering to the cells tended to increase. With polymerase chain reaction analysis it was possible to detect Muc1 gene transcripts in the endometrium at all stages of the oestrous cycle, although the level of Muc1 mRNA decreased by day 10 of dioestrus. The levels of Muc1 mRNA in bitches with a clinical stage of pyometra were low and comparable to those at day 10 of dioestrus. The number of E. coli adhering to the endometrium and Muc1 mRNA levels in the endometrium were inversely correlated (r=-0.77, P<0.01). Immunohistochemical analysis showed little staining for Muc1 in the endometrial epithelia at day 10 of dioestrus and in bitches with pyometra. These results suggest that reduction of Muc1 expression is associated with increased E. coli adherence in the canine uterus at the early stage of dioestrus, possibly facilitating the development of pyometra.

Animals↗

Effect of CIDR-based protocols for timed-AI on the conception rate and ovarian functions of Japanese Black beef cows in the early postpartum period.

Our objectives were to compare: (1) conception rates (in early postpartum Japanese Black beef cows) to timed-artificial insemination (timed-AI) among Ovsynch and Ovsynch plus CIDR protocols, and a protocol that used estradiol benzoate (EB) in lieu of the first GnRH of the Ovsynch plus CIDR; and (2) the effects of these protocols on blood concentrations of ovarian steroids. Cows in the control group (Ovsynch; n=35) underwent a standard Ovsynch protocol (GnRH analogue on Day 0, PGF(2 alpha) analogue on Day 7 and GnRH analogue on Day 9), with timed-AI on Day 10, approximately 20 h after the second GnRH treatment. Cows in the Ovsynch+CIDR group (n=31) received a standard Ovsynch protocol plus a CIDR for 7 days (starting on Day 0). Cows in the third treatment group (EB+CIDR+GnRH; n=41) received 2mg of EB on Day 0 in lieu of the first GnRH treatment, followed by the same treatment as in the Ovsynch+CIDR protocol. The conception rate tended to be greater in the Ovsynch+CIDR group (67.7%, P<0.15) and was greater in the EB+CIDR+GnRH (73.2%, P<0.05) and CIDR-combined (both CIDR-treated groups were combined) groups (70.8%, P<0.05) than in the Ovsynch group (48.6%). Plasma progesterone concentrations were higher on Day 7 (P<0.01) and lower on Days 14, 17 and 21 (P<0.001) in the CIDR-combined group than in the Ovsynch group. Plasma estradiol-17beta concentrations were higher on Day 7 in the Ovsynch group of non-pregnant cows than in the CIDR-combined group of non-pregnant cows and in an all-combined group (all treatment groups combined) of pregnant cows (P<0.01). Furthermore, estradiol-17beta concentrations were lower on Day 9 in the Ovsynch and CIDR-combined groups of non-pregnant cows than in the all-combined group of pregnant cows (P<0.05). In conclusion, both protocols using CIDR improved conception rates following timed-AI in early postpartum suckled Japanese Black beef cows relative to the Ovsynch protocol. Treatment with a CIDR may prevent early maturation of follicles observed in non-pregnant cows treated with the Ovsynch protocol, by maintaining elevated blood progesterone concentrations until PGF(2 alpha) treatment.

Administration, Intravaginal↗

Detection of transforming growth factor-alpha and epidermal growth factor receptor mRNA and immunohistochemical localization of the corresponding proteins in the canine uterus during the estrous cycle.

Uterine expression of the epidermal growth factor (EGF) family of growth factors has not been studied in the dog. The present study looks at the presence of mRNA transcripts and immunohistochemical localization for transforming growth factor-alpha (TGF-alpha), which is the potent EGF family member, and for EGF receptor (EGF-R) in the canine uterus during the estrous cycle. The reverse transcriptase-polymerase chain reaction together with sequencing of the products confirmed the presence of their mRNA transcripts in the endometrium throughout the estrous cycle. Immunohistochemical analysis found clear positive staining for TGF-alpha and EGF-R in the luminal and glandular epithelia at proestrus and estrus. Immunoreactivity decreased at the early stage of diestrus. In the mid stage of diestrus, clear staining for TGF-alpha was again found in the glands of the luminal region, and staining for EGF-R was observed in all glands. Very little staining was seen at anestrus for either TGF-alpha or EGF-R. These results suggest that TGF-alpha expressed in the uterus may be involved in regulating growth, differentiation and regression in the endometrial epithelial cells during the estrous cycle in the dog.

Animals↗

Improved conception in timed-artificial insemination using a progesterone-releasing intravaginal device and Ovsynch protocol in postpartum suckled Japanese Black beef cows.

The primary objective was to determine the effect of supplemental progesterone, administered via an intravaginal device (CIDR), on conception rates to timed-artificial insemination (timed-AI) in postpartum suckled Japanese Black beef cows treated with the Ovsynch protocol. A secondary objective was to compare the effects of treatments on plasma concentrations of progesterone and estradiol. Cows in the control group (Ovsynch, n=38) received a standard Ovsynch protocol (100 microg GnRH analogue on Day 0, 500 microg PGF2alpha analogue on Day 7, and 100 microg GnRH analogue on Day 9), with AI on Day 10, approximately 20 h after the second GnRH treatment. Cows in the treatment group (Ovsynch+CIDR; n=40) received a standard Ovsynch protocol plus a CIDR for 7 days (starting on Day 0). Plasma progesterone concentrations were determined on Days 0, 1, 7, 9, 10, and 17 and plasma estradiol-17beta concentrations were determined on Days 7, 9, 10, and 17. The odds ratio for likelihood of conception was 3.29 times greater (P=0.02) in the Ovsynch+CIDR group compared to Ovsynch group. The conception rate was greater (P=0.03) in the Ovsynch+CIDR group than in the Ovsynch group (72.5% versus 47.7%). Insertion of a CIDR device significantly increased plasma progesterone concentrations only on Days 1 and 7 (P<0.001 and P=0.05, respectively), but had no significant effect on plasma estradiol-17beta concentrations. Including a CIDR with the Ovsynch protocol significantly improved conception rates in postpartum suckled Japanese Black beef cows.

Administration, Intravaginal↗

The effects of the aromatase inhibitor fadrozole hydrochloride on fetuses and uteri in late pregnant rats.

It is well known that progesterone and estrogen are essential hormones for maintaining pregnancy in most mammals. Some specific roles of progesterone for the maintenance of pregnancy have been clarified, but the role of estrogen is not well known. This study examines the effects of the aromatase inhibitor, fadrozole hydrochloride (Fad), on fetuses, uterine physical properties and the mRNA expression of the uterine enzymes that are related to collagen metabolism during late pregnancy in rats. Continuous s.c. infusion with 300 micro g/day Fad from day 14 of pregnancy (day 1=the day of sperm detection) reduced the concentration of plasma estradiol-17beta (E(2)), and did not change that of plasma progesterone, compared with controls. The treatment increased the intrauterine pressure and reduced the size and compliance of the uterine tissue framework. It also caused injuries (hematomata on the extremities) in about one-quarter of fetuses by day 20. The collagen content of the uterine ampullae was not changed by the treatment. Uterine mRNA expressions of matrix metalloproteinase-1 (MMP-1), which degrades collagens, and of lysyl oxidase (LO), which is necessary for the formation of intra- and inter-molecular cross-links of collagen, were examined by quantitative RT-PCR. The treatment with Fad had no effect on the expression of MMP-1 mRNA and increased that of LO mRNA. Daily s.c. injection with 0.2 micro g E(2) restored the changes in uterine physical properties and the mRNA expression of LO caused by the Fad treatment, and prevented fetal injury, indicating that the influences of Fad treatment are due to estrogen deficiency but not to toxicological effects of Fad. These results imply that estrogen deficiency during late pregnancy in rats obstructs development of the uterine tissue framework so as to cause fetal injury. It is possible that an increase in the uterine expression of LO gene may be involved in this obstruction.

Animals↗

Delayed implantation induced by fadrozole hydrochloride in rats.

The effect of aromatase inhibitors on the implantation process is not well known. This study examined the anti-implantation action in rats of a nonsteroidal aromatase inhibitor of high specific activity, fadrozole hydrochloride (Fad). Continuous subcutaneous infusion of Fad at 300 microg/day from Day 1 (the day of sperm detection) through Day 7 of pregnancy using a mini-osmotic pump was found to delay the initiation of implantation by 1 or 2 days with no negative effects on embryonic viability. The Fad treatment delayed preimplantation embryo development and zona shedding by embryos. The treatment also delayed the period of maximum sensitivity to a decidualizing stimulus (intraluminal infusion of sesame oil) by 2 days. The results show that continuous treatment with Fad has multiple anti-implantation effects in rats.

Animals↗

Change in concentrations of luteinizing hormone subunit messenger ribonucleic acids in the estrous cycle of beef cattle.

Changes in the concentrations of LH subunit messenger ribonucleic acids (mRNAs) and in the LH content of the anterior pituitary of beef cattle were studied during the estrous cycle. Japanese beef cows were classified according to the expected day of the estrous cycle: stage I (early-luteal phase, days 1-4; day 1=day of ovulation), stage II (early-mid-luteal phase, days 5-10), stage III (late-mid-luteal phase, days 11-17) and stage IV (follicular phase, days 18-20), according to the morphology of the ovaries. The anterior pituitaries of the cows were collected and the levels of alpha and LHbeta subunit mRNAs were determined by slot-blot analyses. The LH content of the anterior pituitary was measured by radioimmunoassay. The level of alpha subunit mRNA in the pituitary of cows was highest in stage I and decreased significantly by stage II (P<0.05); thereafter it tended to increase. The level of LHbeta subunit mRNA did not change significantly during the estrous cycle. The LH content of the pituitary of cows was low in stage I and tended to increase by stage II, then to decrease from stage II to III, and to increase significantly from stage III to IV (P<0.05). These results suggest that the highest levels of gene expressions of alpha subunit in the anterior pituitary occur in the early-luteal phase of beef cows, while the LH content is increased most in the follicular phase. The enhanced gene expressions of common alpha subunit in the early-luteal phase could be important in replenishing the bovine anterior pituitary with LH, which is depleted of hormone by the LH surge or the enhanced pulsatile release.

Animals↗

The effect of transforming growth factor-alpha on the progression of decidualization in rats.

Although transforming growth factor-alpha (TGF-alpha), one of the epidermal growth factor (EGF) family of growth factors, is expressed in the rat decidual cells, its roles in decidualization remain to be elucidated. This study examined the effect of TGF-alpha on the progression of decidualization and a possibility for involvement of prostaglandins (PGs) in its action. Pseudopregnant rats were ovariectomized and given endometrial trauma on Day 5 (vaginal plug = Day 1) and were daily treated with 2 mg progesterone thereafter. Immunocytochemical localization of EGF receptor was distinctly evident in the decidual, stromal and epithelial cells on Day 7. Continuous infusion of TGF-alpha (500 pg/h) into the uterine lumen from Day 7 significantly increased weights of the uterine horns with deciduomata on Day 9. Although injection on Day 7 of indomethacin, an inhibitor of PGs synthesis, decreased the uterine weight, this effect was overridden by the continuous infusion of this growth factor. These results demonstrated the stimulatory action of TGF-alpha on the progression of decidualization. Further, TGF-alpha increased the secretion of prostaglandin E in cultured decidual and/or stromal cells dose-dependently, suggesting the possibility that PGs mediate the action of this growth factor.

Animals↗

In situ telomerase activity in pleural effusions: a promising marker for malignancy.

Telomerase activity in 16 pleural effusions was studied using an in situ telomerase repeat amplification protocol (TRAP) assay on cytospin preparations. Six of nine cytologically malignant specimens contained telomerase-positive cells (67%), and in two further specimens, suspicious positive cells were seen. Two of four atypical specimens contained telomerase-positive cells, whereas two benign cases were telomerase-negative. No mesothelial cells showed telomerase reactivity. Thus, telomerase activity was specific for malignancy and it was always found only in malignant cells. The results suggest that telomerase activity measured with this in situ method can be a valuable complement in the assessment of malignancy in pleural effusions.

Biomarkers, Tumor↗

K-ras mutation in sputum of primary lung cancer patients does not always reflect that of cancerous cells.

K-ras mutation in sputum was examined using mutant-allele-specific amplification method among 100 primary lung cancer and 15 non-oncological patients. K-ras mutation was detected in 11 out of 59 adenocarcinoma cases (18.6%), 5 out of 32 squamous cell carcinoma cases (15.6%), 2 out of 4 large cell carcinoma cases (50.0%) and 3 out of 15 non-oncological disease cases (20.0%). In the 18 cases of primary lung cancer K-ras mutation was examined in both sputum and the resected specimen of the primary lesion. In 5 cases K-ras mutation in sputum was detected without K-ras mutation in primary lesion. Therefore, these findings suggested that K-ras mutation in sputum may not be directly related to that of the primary lesion.

Adult↗

[Carinal resection of bronchogenic carcinoma].

Carinal resection was performed in 10 cases of bronchogenic carcinoma during 12 year-period. The mean age of patients was 58 years, with a range of 42 to 68 years. There were 7 male and 3 female. The tumor was located on the right side in 7 cases, on the left side in 1 case on the carina in 2 cases. The histological examination showed squamous cell carcinoma in 5 cases, adenocarcinoma in 4 cases and adenoid cystic carcinoma in 1 case. The staging revealed T3N2 M0 Stage IIIA in 2 cases, T4N0M0 Stage IIIB in 1 case, T4N1M0 Stage IIIB in 1 case, T4N2M0 Stage IIIB in 5 cases and T4N3M0 Stage IIIB in 1 case. The surgical methods were as follows; sleeve pneumonectomy in 5 cases, wedge carinal resection with pulmonary resection in 3 cases (right sleeve upper lobectomy in 2 cases and right pneumonectomy in 1 case), carinal resection in 2 cases. The site of bronchial anastomosis was overlapped by thymus in 6 cases. The 30-day mortality rate in tracheo-carinal resection was 10% (one patient). Eight patients died and remaining 2 patients are still alive without any evidence of recurrence. 5-year survival rate was 36%. These outcomes were almost equal to those of surgical case in the same stage.

Adenocarcinoma↗

Roles of pulsatile release of LH in the development and maintenance of corpus luteum function in the goat.

The roles of the pulsatile release of LH in the functional development and maintenance of the corpus luteum (CL) during the estrus cycle in the goat were examined using a potent GnRH antagonist. In Experiment 1, to assess the inhibitory effects of the GnRH antagonist on the release of LH during the estrus cycle, 9 goats were divided into 3 groups. Goats in Group I received only saline on Days 0 (day of ovulation), 5, 10 and 15. Goats in Group II received the GnRH antagonist (50 microg/kg, s.c.) on the days mentioned for Group I to inhibit endogenous LH during the periods of luteal development and maintenance. Goats in Group III received saline on Days 0 and 5 and then the GnRH antagonist on Days 10 and 15 to inhibit LH during the period of luteal maintenance. Serial blood sampling took place on Days 1, 3, 5, 8, 13 and 18 to characterize the LH pulses. The LH pulses were observed throughout the estrus cycle in Group I but were completely abolished in Group II. In Group III, the pulsatile release of LH was observed from Day 1 to 8, but the LH pulses were completely abolished on Days 13 and 18. In Experiment 2, 16 goats were divided into the same 3 groups as in Experiment 1 to examine the effects of the GnRH antagonist on the luteal function. The concentration of progesterone in the plasma in Group I increased after ovulation, reached a maximum level around Day 12, and subsequently returned to the basal level on Day 17. The concentrations of progesterone in Group II rose after ovulation, but reached a plateau around Day 6 and maintained the level up to Day 9, then rapidly decreased from Day 9 to 10 to the basal level. The concentrations of progesterone in Group II were lower on Days 7 to 15 than those in Group I (P<0.01). The concentrations of progesterone in Group III increased after ovulation, reached a maximum level around Day 8, then dropped from Day 10 to 13 to the basal level. The concentrations of progesterone in Group III on Days 11 to 15 were lower than those in Group I (P<0.05 on Day 11, P<0.01 on Days 12 to 15). These results demonstrate that endogenous LH is essential for normal development and maintenance of the CL function during the estrus cycle in the goat. Further, this study suggests that while the functional maintenance of the caprine CL depends entirely on LH support, such functional dependence during early CL development is only partial.

Animals↗

Epidermal growth factor (EGF) in the goat uterus: immunohistochemical localization of EGF and EGF receptor and effect of EGF on uterine activity in vivo.

This study examined the distribution of immunoreactive epidermal growth factor (EGF) and EGF receptor (EGF-R) in the uterus and the effects of EGF on uterine activity in goats. Immunohistochemistry of EGF and EGF-R in the uteri showed distinct staining in the luminal and glandular epithelium and slight to moderate staining in the stromal and myometrial cells. To examine possible roles of the EGF system in the regulation of uterine activity, pressure changes in the intrauterine balloon were determined after intraluminal infusion of EGF into the uterine horn. Either at estrus or diestrus (9 to 14 days after the first day of estrus), treatment with 1 or 5 microg of EGF gradually reduced uterine activity, whereas infusion of the vehicle alone had no effect. The maximum reduction in uterine activity was seen 4 h after the treatment with 1 microg of EGF (40% to 45% reduction in the area surrounded by the contraction curve and its baseline), and the activity slowly returned thereafter. These results suggest that EGF in the uterus may play a role in regulating uterine activity in goats.

Animals↗