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Biomedical subjects

E Kawakami

Publications and source records attributed to E Kawakami.

At least 19 recordsLinked to original sources

Changes in activities of enzymes related to energy metabolism in peripheral leukocytes of diabetic dogs with glycemic control by intensive insulin treatment.

Changes in plasma glucose, immunoreactive insulin (IRI), and free fatty acids (FFA) concentrations and activities of enzymes related to energy metabolism in peripheral leukocytes were measured in type 1 diabetic dogs induced by streptozotocin administration before and after intensive insulin treatments. Before the insulin treatment, the plasma glucose concentrations were over 16.7 mmol/L and the activities of enzymes remarkably decreased in leukocytes of the diabetic dogs. In particular, malate dehydrogenase (MDH) activities decreased significantly. After glycemic control was achieved by insulin treatment, the plasma glucose concentrations were maintained between 6.8 and 7.7 mmol/L and the activities of enzymes restored to those in the control dogs. The changes in ML ratio (cytosolic MDH/lactate dehydrogenase specific activity ratio) reflected faithfully to metabolic conditions of animals and were considered to be a useful parameter to evaluate glycemic control and the effect of injected insulin in the diabetic dogs.

Animals↗

Changes in activities of enzymes related to energy metabolism in testicular tissues of dogs with seminoma.

Changes in the activities of enzymes related to energy metabolism in the testicular tissues of dogs with seminoma were investigated. The testis was removed surgically from animals anaesthetized with halothane. Cytosolic and mitochondrial fractions were isolated and the total RNA was extracted from testicular homogenates. The activities of enzymes related to energy metabolism were measured and the mRNA of cytosolic malate dehydrogenase (MDH) was investigated by the reverse transcriptase-polymerase chain reaction (RT-PCR). The activities of the glycolytic enzymes glucose-6-phosphate dehydrogenase (G6PD) for the pentose phosphate pathway and malate dehydrogenase (MDH) for the malate-aspartate shuttle, and the expression of the mRNA of cytosolic MDH were significantly increased in the testicular tissues of dogs with seminoma. These enzymatic activities may be useful indicators with which to evaluate changes in the metabolic conditions in testicular tissues of dogs with seminoma.

Animals↗

Effects of canine oviduct epithelial cells on movement and capacitation of homologous spermatozoa in vitro.

In this study, the interaction between canine sperms and oviduct epithelial cells (OECs) was examined in vitro. The oviducts of eight bitches in the follicular (F-) phase and six bitches in the luteal (L-) phase were removed under halothane inhalation anesthesia. The entire oviduct was opened longitudinally, and the oviductal epithelium of bitches in the F- and L-phases was scraped with a scalpel into tissue culture medium (Eagle's MEM) containing 10% estrous bitch serum and 10% diestrous bitch serum, respectively. The OEC collected were preincubated for 24h and then coincubated with ejaculated canine sperms at 38 degrees C under an atmosphere of 5% CO2 in air. The percentages of sperms exhibiting active tail movement (% TM), hyperactivated sperms (% HA), and acrosome-reacted sperms (% AR) were investigated until 72 h after the start of coincubation. The percentage of sperms labeled with fluoresceinated Ca indicator (% Ca) was evaluated to assess the influx of Ca into sperms cytoplasm during capacitation. Canine sperms attached to both ciliated OEC and non-ciliated OEC. All of the mean % TM of the OEC-binding sperms in the F-OEC and L-OEC media after 24, 48, and 72 h of coincubation were significantly higher than the values of the freely swimming sperms (P< or =0.01). Conversely, the mean % AR and % Ca of the OEC-binding sperms were significantly lower (P<0.01). All of the mean % HA and % AR of the freely swimming sperms in the F-OEC medium after 24, 48, and 72 h of coincubation were significantly higher than the values of the sperms in the L-OEC medium (P< or =0.01). These results indicate that attachment of canine sperms to the OEC prolongs their viability and motility arid inhibits Ca influx into the sperms and sperm capacitation. These phenomena may be responsible for maintaining the active movement and the fertile life of canine sperms in homologous oviducts.

Acrosome↗

A simple objective parameter for perfusion study of renal transplant.

We proposed a simple parameter, the kidney-to-aorta ratio (KAR), for evaluation of renal transplant perfusion. KAR was calculated from the peak counts of the kidney and the aorta. The calculated values were compared with the visual interpretation of the radionuclide first-pass flow study, percent renal uptake (%RU), and tubular extraction rate (TER) by Bubeck's one point sampling method in 37 studies. KAR correlated well with the visual interpretation of the flow study and the other quantitative parameters. Representative cases, which showed the usefulness of KAR for the objective assessment of the perfusion status of renal transplants, were presented. In conclusion, KAR is a simple and practically useful parameter for objective evaluation and follow-up of renal transplant perfusion.

Adult↗

Transfer of canine embryos at various developmental stages recovered by hysterectomy or surgical uterine flushing.

In dogs, embryo transfer (ET) techniques such as induciton of excessive ovulation and synchronization of estrus have not progressed well. Therefore, using embryos at various developmental stages, ET was investigated in dogs from a beagle colony in which the ovulation days were close, as estimated by the progesterone level. Embryos were, recovered 8-11 days after ovulation (4-9 days after mating) by excising the oviducts and uteri (excision method) in 16 animals and by surgical flushing of the uteri at laparotomy (surgical method) in 3 animals. In 24 dogs with -4 to +2 days of difference in the timing of ovulation between donor and recipient dogs, 1-10 embryos at the 8-cell to blastocyst stages were transferred per animal. The mean embryo recovery rate by the excision method (97.1%) was significantly higher than that by the surgical method (42.5%) (p<0.01). Twelve (57.1%) of 21 animals with -1 to +2 days difference in ovulation day became pregnant after the transfer of 8-cell to blastocyst stage embryos. Although 3 dogs with -4 to -2 days of difference of ovulation day underwent ET of morula or compacted morula, none of these dogs became pregnant. The mean ratio of the number of newborns to the number of transferred embryos was only 51.9%. The mean duration of the period between ovulation and delivery in the pregnant recipients was 65.8 days, which tended to be longer than that in natural mating. These results demonstrate that pregnancy can be induced by ET at the 8-cell to blastocyst stage in dogs with -1 to +2 days difference in ovulation day.

Animals↗

High plasma estradiol-17beta levels in dogs with benign prostatic hyperplasia and azoospermia.

The semen quality of 22 dogs (4 to 7 years old) with benign prostatic hyperplasia (BPH) was examined at the hospital of our university, and 4 of the 22 BPH dogs were diagnosed as azoospermic. The mean peripheral plasma estradiol-17beta (E2) level (17.3 pg/ml) of the 18 BPH dogs with spermatogenic function was higher than that of 5 normal male dogs and their mean T level (1.7 ng/ml) was lower. The mean E2 level (27.3 pg/ml) of the 4 BPH dogs with azoospermia was significantly higher than the value in the BPH dogs with spermatogenic function (P<0.01), and the mean T level (1.1 ng/ml) was significantly lower (P<0.05). Five normal male dogs were given 10 intramuscular injections of estradiol benzoate (E2B) 5 microg/kg, at 3-day intervals to investigate the relationship between high plasma E2 levels and the cause of the BPH and azoospermia. Their testes and prostates were measured and biopsied both before and 30 days after the start of E2B injections. At 30 days after the start of the E2B injections, the mean peripheral plasma T levels had decreased by half, and the mean testicular volume had decreased to 88% of original volume. The numbers of spermatocytes, spermatids, and spermatozoa in the seminiferous tubules of all of the dogs were significantly lower (P<0.05, 0.01). In addition, the mean prostatic volume increased to 130%, the mean height of the glandular epithelium decreased, and the glandular lumen became increased in diameter. These findings indicate that both BPH and serious spermatogenic dysfunction may be simultaneously induced by protracted high plasma E2 levels in dogs.

Animals↗

Effect of osaterone acetate administration on prostatic regression rate, peripheral blood hormone levels and semen quality in dogs with benign prostatic hypertrophy.

The effects of osaterone acetate (OSA), which is an anti-androgen agent being developed as a therapeutic drug for benign prostatic hypertrophy (BPH) in dogs, on the degree of prostatic regression and semen qualities were investigated. Prostatic regression was compared between dogs with and without orchidectomy. Five male beagles aged 5-9 years were used in the experiment. OSA was orally administered at doses of 0.2 mg/kg and 0.5 mg/kg for one week. The prostatic regression rate one week after the end of administration was 62.6% on average. In the orchidectomized group, the mean regression rate one week after orchidectomy was 60.1%. However, the prostate became enlarged 6 months after administration, compared to the size prior to administration. The above findings suggested that OSA is clinically applicable as a therapeutic drug for BPH in dogs, and inhibits prostatic hypertrophy during the early phase.

Androgen Antagonists↗

Relationship between testicular transferrin and plasma estradiol-17beta concentrations of dogs with azoospermia and dogs with sertoli cell tumors.

Testicular Transferrin (Tf) and peripheral plasma estradiol-17beta (E2) concentrations were measured in 3 dogs with azoospermia (AZ dogs), 3 dogs with Sertoli cell tumors (SC dogs), and 5 normal male Beagles. The mean Tf concentrations in the testes of the AZ dogs and the affected testes of the SC dogs, and the plasma E2 concentrations in both these groups of dogs were significantly higher than the values in normal dogs (P<0.05, 0.01 and 0.01, respectively). Therefore, excessive E2 secretion by hyperfunctioning Sertoli cells is thought to have caused the azoospermia in the 3 dogs.

Animals↗

Evaluation of invasive and non-invasive methods for the diagnosis of Helicobacter pylori infection in symptomatic children and adolescents.

CONTEXT: Multiple diagnostic methods are available for the detection of Helicobacter pylori infection, but at present no single one can be used as the gold standard. OBJECTIVE: The aim of this study was to evaluate the diagnostic accuracy of 3 invasive and 2 non-invasive methods for detection of Helicobacter pylori infection in symptomatic children and adolescents. DESIGN: Prospective cohort study SETTING: Peptic Disease outpatients service, Discipline of Pediatric Gastroenterology, Universidade Federal de São Paulo / Escola Paulista de Medicina. PATIENTS: Forty-seven patients who underwent endoscopy because of dyspeptic symptoms. DIAGNOSTIC METHODS: Endoscopy with gastric biopsies for 3 invasive (rapid urease test, histology and culture) and 2 non-invasive methods (a commercial ELISA serology and 13carbon urea breath test - isotope ratio mass spectrometry) for detection of Helicobacter pylori infection. MAIN MEASUREMENTS: Sensitivity, specificity, positive and negative predictive values of each method and agreement and disagreement rates between the methods. RESULTS: Forty-seven patients [mean age, 11y9mo (SD 2y10mo), 27 female and 20 male]; 62% of them were Helicobacter pylori-positive. All methods agreed in 61%, and were negative in 21% and positive in 40%. The greatest concordance between 2 methods occurred between the invasive methods: histology and rapid urease test (89.6%) and histology and culture (87.5%). The greatest sensitivity, considering Helicobacter pylori-positive cases, for any combination of 3 or more tests, was achieved by the rapid urease test (S=100%), followed by histology, serology and 13carbon-urea breath test (S=93.1%) and lastly by culture (S=79.3%). The highest specificity was obtained by histology (100%) and culture (100%), followed by the rapid urease test (84.2%), serology (78.9%) and 13carbon-urea breath test (78.9%). CONCLUSIONS: Our results suggest that among invasive methods, an association between the rapid urease test and histology constituted the best choice for the detection of Helicobacter pylori infection. If results of histology and the rapid urease test are different, serology may be recommended.

Adolescent↗

Intratubal transplantation of early canine embryos.

It has been reported previously that intrauterine transplantation of canine embryos is possible. In this study, the possibility of intratubal transplantation of early canine embryos was investigated. Beagles at ovulation +/- 1 day estimated from peripheral blood progesterone concentrations were used as embryo donors and recipients. The Beagles (n = 13) were mated 1-4 days after ovulation and embryos were collected 1-3 days after mating (3-7 days after ovulation) by tubal flushing or salpingectomy. Embryos were transplanted using a glass tube or catheter into the upper or lower uterine tubes at 1.5 and 5.0 cm from the fimbriae tubae, respectively. The mean embryo yield from three bitches from which embryos were collected by tubal flushing was 28.2%. Embryos collected from ten bitches by salpingectomy were at the syngamy to eight-cell stages of development, and the mean yield was 95%. Embryos (1-7 per bitch) were transplanted into the upper uterine tube of seven recipient bitches and to the lower uterine tube of eight recipient bitches. It was found that no bitches in which embryos were transplanted into the upper uterine tubes became pregnant, whereas four bitches (50%) in which embryos were transplanted into the lower uterine tubes became pregnant (P < 0.05, chi-squared test). The success of embryo transfer was not affected by differences in embryo stage or day of ovulation. In conclusion, it is possible to impregnate bitches by transplanting early canine embryos into the lower uterine tubes.

Animals↗

Ciliochoroidal Detachment Following Scleral Buckling Surgery for Rhegmatogenous Retinal Detachment.

Purpose and Methods: We observed the peripheral choroid, ciliary body, and depth of the anterior chamber by ultrasound biomicroscopy (UBM) in 31 eyes with rhegmatogenous retinal detachment before and after scleral buckling surgery. Scleral encircling was performed in 11 eyes and segmental scleral buckling in 20 eyes.Results: With UBM, ciliochoroidal detachment was detected in all eyes (100%) following scleral encircling and in 8 eyes (40.0%) following segmental scleral buckling. After scleral encircling procedure, the eyes with preoperatively bullous and wide retinal detachment showed a severe ciliochoroidal detachment and edema of the ciliary body. Shallowing of the anterior camber occurred in all 11 eyes (100%) after scleral encircling and in 12 of 20 eyes (60.0%) after segmental scleral buckling. Marked shallowing with closure of the angle and elevated intraocular pressure occurred in 2 eyes.Conclusion: The results showed that careful postoperative examinations for the anterior segments, chamber angle, and intraocular pressure are necessary with slit-lamp examination and applanation tonometry after scleral buckling surgery.

Journal Article↗

Regression of prostatic hypertrophy by osaterone acetate in dogs.

The prostatic regression effect of oral administration of a new steroidal anti-androgen, osaterone acetate, was investigated in dogs with prostatic hypertrophy. To dogs with prostatic hypertrophy, 0.1-1.0 mg/kg of osaterone acetate was orally administered for one week, and the regression rate was observed. It was shown that administration of osaterone acetate at 0.2 mg/kg or higher, sharply regressed prostatic hypertrophy during the early stage. Therefore, this agent may be clinically applicable as a therapeutic agent for benign prostatic hypertrophy.

Administration, Oral↗

Changes in plasma testosterone and testicular transferrin concentration, testicular histology and semen quality after treatment of testosterone-depot plus PMSG to 3 dogs with asthenozoospermia.

Three dogs diagnosed as having asthenozoospermia were given three intramuscular injections of 50 mg testosterone(T)-depot plus 250 IU pregnant mare serum gonadotropin (PMSG) at 2-week intervals, and their plasma T and testicular transferrin (Tf) concentrations, testicular histology, and semen quality were examined during the period of hormone therapy. Plasma T concentrations temporarily increased, and there was a slight improvement in spermatogenesis. Increased Tf concentrations suggested that Sertoli cell function in all three dogs was promoted by hormone treatment. The results showed that semen quality, especially the percentages of motile sperm and abnormal sperm, were improved between 1 and 5 weeks after the start of T-depot plus PMSG treatment.

Animals↗

Plasma LH and progesterone levels before and after ovulation and observation of ovarian follicles by ultrasonographic diagnosis system in dogs.

Recently, canine frozen semen has been attracting attention for breeding purposes, and methods of judging ovulation and optimum timing for insemination have become important. As methods of predicting the canine ovulation, vaginal smear, plasma sex hormone levels and ultrasonographic diagnosis system (US) have been investigated in combination, but a standard technique has not yet been established. Therefore, we investigated a method of predicting canine ovulation in dogs by US, and by measuring plasma LH and progesterone (P) levels three times a day. Ovulation could be observed by detecting irregularly shaped ovarian follicles by US in six of 11 dogs (54.5%). In these dogs, the time between the LH peak and ovulation was 24-48 hr, 38.0 hr on average. The P level on the ovulation day was 1.88-2.81 ng/ml, 2.34 ng/ml on average. A value of 1.88 ng/ml was detected in one dog, but the other five dogs showed P levels of 2 ng/ml or higher. The P level on the day before ovulation was 0.8-1.56 ng/ml, 1.12 ng/ml on average. Assuming that ovulation occurred two days after the LH peak in the 11 experimental dogs, the P level was 2.12-4.06 ng/ml, 2.78 ng/ml on average. The period of a high LH level, not less than 10 ng/ml, continued for 12 hr around the LH peak. Based on these findings, to predict ovulation using US and LH level, it would be necessary for the tests to be performed several times a day. In contrast, it was shown that the day on which a plasma P level of 2 ng/ml or higher was detected by the test performed once a day corresponded to the ovulation day.

Animals↗

Azoospermia of dogs with apoptotic germ cells and Leydig cells.

Apoptotic cell death in the testes of 4 dogs with azoospermia was examined. Blood plasma luteinizing hormone (LH), testosterone (T), and estradiol-17beta (E2) concentrations, and testicular transferrin (Tf) concentration as a marker of Sertoli cell function were measured in the 4 azoospermic dogs and in 5 normal dogs. The spermatids in 2 of the 4 azoospermic dogs and the Leydig cells in 3 of them exhibited apoptotic cell death. Mean LH, E2, and Tf concentrations in the 4 azoospermic dogs were significantly higher than in the normal dogs (P<0.01). These findings suggested that the azoospermia in all 4 dogs might has been caused by abnormal functions of Sertoli cells as well as Leydig cells.

Animals↗

Effects of orvus ES paste on canine spermatozoal longevity after freezing and thawing.

Because of weak resistance of canine sperm to freezing, an applicable method of preparing canine frozen semen has not yet been established. We added various concentrations of Orvus ES Paste (OEP) to egg yolk Tris-fructose citrate, and investigated its effectiveness on survival of spermatozoa. Addition of 0.5-1.0% OEP to the extender for freezing canine semen was effective in prolonging post-thaw survival of spermatozoa.

Animals↗

Effect of addition of Orvus ES paste to frozen canine semen extender on sperm acrosomes.

Using the triple-stain technique, we investigated whether sperm acrosomes in frozen canine semen were protected during freezing and thawing by addition of a surfactant, Orvus ES Paste (OEP), to the extender. Acrosomes were clearly shown to be protected by the addition of OEP to the entender when compared with those in sperm frozen without OEP addition (p<0.05).

Acrosome↗

Intrauterine and intravaginal insemination with frozen canine semen using an extender consisting of orvus ES paste-supplemented egg yolk tris-fructose citrate.

Our previous report indicated that addition of Orvus ES Paste (OEP) to the extender of frozen canine semen protected acrosomes and maintained sperm motility after thawing. In this study, artificial insemination (AI) using the frozen semen was carried out. The frozen semen was prepared using egg yolk Tris-fructose citrate, and the final concentrations of glycerol and OEP were 7% (v/v) and 0.75% (v/v), respectively. AI was performed during the optimal mating period predicted from the peripheral plasma progesterone level. In intrauterine insemination (IUI), the bitches were laparotomized and 1 x 10(8) spermatozoa were infused into one of the uterine horns. In insemination of non-OEP supplemented semen, 3 x 10(8) spermatozoa were inseminated. In intravaginal insemination (IVI), 10-40 x 10(8) spermatozoa were inseminated. Conception was obtained in nine of 10 bitches (90.0%) that underwent IUI. The number of newborns was from 1 to 7 (mean 3.6 +/- 0.9). The mean ratio of the number of puppies to the number of ovulations in the inseminated uterine horn was 71.8%. The number of puppies did not exceed the number of ovulation in the inseminated uterine horn. Conception using non-OEP supplemented frozen semen was unsuccessful in all four bitches. In IVI, conception was not obtained in any of the six bitches that received insemination of 10 x 10(8) or 40 x 10(8) spermatozoa, but two of three bitches that received insemination of 20 x 10(8) spermatozoa were fertilized. It was shown that a high conception rate can be obtained by IUI using OEP-supplemented frozen canine semen. Developmenmt of a non-surgical method of IUI and a method of freezing canine sperm applicable to IVI is necessary.

Animals↗