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Shinji Komori

Publications and source records attributed to Shinji Komori.

13 recordsLinked to original sources
PubMed2006

Upregulation of macrophage migration inhibitory factor and calgizzarin by androgen in TM4 mouse Sertoli cells.

AIM: To identify proteins induced by androgen in Sertoli cells during spermatogenesis. METHODS: We analyzed protein profiles in TM4 Sertoli cells treated with dihydrotestosterone (DHT) using surface enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF-MS). RESULTS: We found increases in the expression of a 5.0-kDa protein at 15 min, an 11.3-kDa protein at 24 h and 4.3 kDa, 5.7 kDa, 5.8 kDa, 9.95 kDa and 9.98 kDa proteins at 48 h after the treatment. In contrast, the expression of 6.3 kDa and 8.6 kDa proteins decreased at 30 min, and 4.9 kDa, 5.0 kDa, 12.4 kDa and 19.8 kDa proteins at 48 h after the treatment. The 11.3-kDa protein was identified as macrophage migration inhibitory factor (MIF) known to having various functions. The 9.98-kDa protein was identified as calgizzarin related to calcium channels. The timing of their expression suggests that MIF and calgizzarin are involved in late regulation of spermatogenesis in Sertoli cells by androgen. CONCLUSION: MIF and calgizzarin are two important androgen-responsive proteins produced by Sertoli cells and they might play a role in regulating spermatogenesis.

Androgens↗
PubMed2006

Pig zona pellucida 2 (pZP2) protein does not participate in zona pellucida formation in transgenic mice.

The zona pellucida, an extracellular matrix surrounding mammalian oocytes, is composed of three or four glycoproteins. It is well known that the zona pellucida plays several critical roles during fertilization, but there is little knowledge about its formation. The purpose of this study is to examine whether a pig zona pellucida glycoprotein 2 (pZP2) would assemble with mouse zona pellucida. A transgene construct was prepared by placing a minigene encoding pZP2 downstream from the promoter of mouse ZP2. The result showed that the transgenic protein was synthesized in growing oocytes but not incorporated into the zona pellucida. Furthermore, the pZP2 transgene did not rescue the phenotype in ZP2-knockout zona-deficient mice. These results indicate that pZP2 does not participate in mouse zona pellucida formation and the zona pellucida is constituted from its component proteins in a molecular species-specific manner between mice and pigs.

Animals↗
PubMed2004

Birth of healthy neonates after intracytoplasmic injection of ejaculated or testicular spermatozoa from men with nonmosaic Klinefelter's syndrome: a report of 2 cases.

BACKGROUND: Klinefelter's syndrome is one of the major causes of azoospermia, cryptozoospermia and severe oligozoospermia with either a nonmosaic (47,XXY) or mosaic (47,XXY/46,XY) ICSI treatment with cryopreserved testicular spermatozoa failed, but after the third attempt, 6 of 8 oocytes injected with cryopreserved sperm were fertilized and karyotype. Men with Klinefelter's syndrome generally have difficulty having children. CASES: Patient 1 had motile spermatozoa in the ejaculate, which were injected into 3 oocytes, resulting in fertilization and cleavage. Two good-quality embryos were transferred into his wife's uterine cavity. She conceived and, following a normal pregnancy, delivered a healthy female infant. Two years later she conceived for the second time with motile spermatozoa in the ejaculate and delivered a healthy male infant uneventfully. To our knowledge, this was the first case in which a nonmosaic Kleinefelter's syndrome patient fathered 2 children through intracytoplasmic sperm injection (ICSI) using motile spermatozoa in the ejaculate. Patient 2, with azoospermia, was subjected to testicular biopsy to collect spermatozoa. The first 2 attempts at ICSI treatment with cryopreserved testicular spermatozoa failed, but after the third attempt, 6 of 8 oocytes injected with cryopreserved sperm were fertilized and cleaved. Two of these embryos were transferred into the wife's uterine cavity. She conceived and, following a normal pregnancy, delivered a healthy male infant. In all cases, amniocentesis followed by genetic analysis showed a normal karyotype. CONCLUSION: Two infertile men with nonmosaic Klinefelter's syndrome successfully fathered normal children after intracytoplasmic injection of ejaculated or testicular spermatozoa.

Adult↗
PubMed2003

Prevention of multiple pregnancies by restricting the number of transferred embryos: randomized control study.

INTRODUCTION: The high incidence of multiple pregnancies is a major concern in the treatment of infertility by in vitro fertilization (IVF). Risks and costs are associated with multiple pregnancies and it is important to find a way to decrease multiple pregnancies. The standard protocol for IVF includes the transfer of two or three embryos. METHODS: In this study, we compared the rate of single and multiple pregnancies between patients who received two and three embryos. One hundred and sixty-nine patients were randomly divided into two groups, with 106 cycles of IVF each. Group 1 received two embryos, and group 2 three. RESULTS: Group 1 had total 40 (37.8%) pregnancies, while group 2 had 29 (27.4%). The number of ongoing pregnancies was 33 (31.1%) in group 1 and 26 (24.5%) in group 2. The number of baby-take-home was 32 (30.1%) in group 1 and 26 (24.5%) in group 2. These results show that there was no significant difference between the two groups in both the total and ongoing pregnancies. On the other hand, the number of twin pregnancies was 6 (15.0%) in group 1 and 12 (41.4%) in group 2, showing a significant difference. Group 1 had no triplet pregnancies, while Group 2 had two. CONCLUSION: We conclude that the transfer of two embryos reduces the incidence of multiple pregnancies while maintaining an acceptable rate of pregnancy in IVF.

Embryo Transfer↗
PubMed2003

The primary varicella infection near term: a case report.

A 33-year-old pregnant woman developed skin rash at the 40 weeks' gestation. She was diagnosed as primary varicella zoster infection. Upon hospitalization, she was administered acyclovir and also a tocolytic agent (ritodorine hydrochloride) to postpone labor. The patient delivered a female baby 7 days after she developed skin lesions. Serological tests conducted after delivery showed that the mother was positive for IgG and IgM against varicella zoster. The baby was observed in a neonatal intensive care unit and found to be free of varicella zoster symptoms.

Acyclovir↗
PubMed2003

Isolation and characterization of a human sperm antigen gene h-Sp-1.

We isolated and characterized a human sperm antigen gene (h-Sp-1) from human testis complementary DNA using antiserum against the human sperm membrane. Northern blot analysis detected two transcripts (2.3 and 1.1 kb) of the h-Sp-1 gene. The 2.3-kb transcript is ubiquitous, whereas the 1.1-kb transcript is specific to the human testis with a high level of expression. Determination of the base sequence of h-Sp-1 showed a size of 2170 bp and 43.4% homology with human synaptophysin. The base sequence indicates a molecule consisting of 259 amino acids, with four hydrophilic and four hydrophobic regions. In order to further characterize the h-Sp-1 molecule, we synthesized the probable region of amino acids with high antigenicity based on the amino acid sequence (amino acid nos. 174-198) and immunized rabbits to prepare an antiserum. In our experimental model of fertilization between human sperm and zona pellucida-free hamster ova, partial inhibition of fertilization was observed. We were able to synthesize a large quantity of recombinant protein by inserting the h-Sp-1 gene into a baculovirus vector and infecting spodoptera frugiperda culture cells (sf9 insect cells). The synthesized protein had a molecular weight of 30 kDa. We then immunized Balb/c mice with this protein to prepare a monoclonal antibody (G3G9), which was used to localize the h-Sp-1 molecule in sperm and tissues (e.g. testis). The h-Sp-1 molecule was present in the cell membrane from the head to tail of human sperm. Staining of the testis and epididymis also showed h-Sp-1 to be present in spermatogonia, spermatocyte, sperm and epididymal duct epithelium. These findings suggest that the h-Sp-1 molecule is expressed in sperm and testes and plays a role in fertilization.

Amino Acid Sequence↗
PubMed2003

A digital method of sperm immobilization test: comparison to the conventional method.

Antisperm antibodies have been found in infertile patients and those causing immobilization of sperm are considered to be closely related to unexplained infertility. These antibodies are usually identified by a sperm immobilization test which involves counting motile sperm under microscope. This test is subjective as it relies on the judgement of the examiner with respect to sperm motility. In this study, we analyzed motile sperm by a digital method using Sperm Quality Analyzer. The results were compared with those obtained by the conventional method. We found that the two methods yielded identical results, with 14 of 66 samples tested being positive and 52 negative for sperm immobilizing antibodies. These results show that the digital method is objective and of value in the measurement of motile sperm in determination of sperm immobilizing antibodies.

Agglutination Tests↗
PubMed2003

Diagnostic laparoscopy in infertility: a retrospective study.

STUDY OBJECTIVE: To evaluate the role of laparoscopy in the diagnosis and therapy of infertility. DESIGN: Retrospective study. SETTING: Academically affiliated reproductive endocrinology practice. PATIENTS: One hundred seventy patients. INTERVENTION: Diagnostic/therapeutic laparoscopy. MEASUREMENTS AND MAIN RESULTS: One hundred seventy infertile patients underwent diagnostic laparoscopy between 1996 and 2000 in our clinic, and 109 of them were seen at follow-up more than 1 year after laparoscopy. Of the 109 patients, 77 (70.6%) were treated with assisted reproductive technology, such as in vitro fertilization-embryo transfer, and 32 (29.4%) were treated with conventional procedures. Of the 109 patients, 68 (62.4%), including 39 (50.6%) of the 77 treated with assisted reproductive technology and 29 (90.6%) of the 32 treated with conventional procedures, became pregnant. Of the 68 patients who became pregnant, 49 (72.1%) of them conceived within 1 year after laparoscopy. CONCLUSION: Laparoscopy is an important procedure in the treatment of infertility.

Embryo Transfer↗
PubMed2002

Transmission of Y chromosomal microdeletions from father to son through intracytoplasmic sperm injection.

We conducted chromosomal analysis of three male infants fathered by severe oligozoospermic males with Y chromosomal microdeletions through intracytoplasmic sperm injection (ICSI). Two of the infants had the same Y chromosomal microdeletions as their fathers. The third infant also had a Y chromosomal microdeletion, which was longer than that found in his father. The results confirm that Y chromosomal microdeletions are transmitted from a father to a son via ICSI and also suggest that the microdeletions may be expanded during such transmission. Genetic counseling for infertile couples contemplating ICSI is important if the male carries Y chromosomal microdeletions.

Cytoplasm↗
PubMed2002

Molecular analysis of the Y chromosome AZFc region in Japanese infertile males with spermatogenic defects.

Cytogenetic and molecular studies of azoospermic and oligozoospermic males have suggested the presence of azoospermia factors (AZF) in the human Y chromosome. Deletion in three Y chromosomal regions--AZFa, AZFb and AZFc--has been reported to disrupt spermatogenesis and cause infertility. Several candidate genes responsible for spermatogenesis have been identified in these regions and some of them are thought to be functional in human spermatogenesis. Here we report on clinical and molecular studies of Y chromosome micro-deletions in Japanese. In these studies the data from 157 infertile Japanese men with azoospermia and oligozoospermia was analyzed and divided into 5 categories based on spermatozoa count. Sixteen sets of primers were used for polymerase chain reaction (PCR) to amplify sequence tagged site markers. One common deletion in the AZFc region was identified in infertile men. On the other hand, no deletions around the AZFc region were identified in fertile men. Japanese infertile men in our study had a common deletion in the AZFc region of the Y chromosome. A genomic clone was obtained by PCR screening of the P1 phage artificial chromosome (PAC) library. This clone was analyzed by Southern blotting using a PCR amplified probe of sY240. Our analysis of the genomic sequence of the clone suggests that this locus may contain specific genes for spermatogenesis.

Base Sequence↗