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Abstract
The male reproductive system consists of testes, a series of ducts connecting the testes to the external urethral orifice, accessory sex glands, and the penis. Spermatogonial stem cells differentiate and mature in testes and epididymides, and spermatozoa are ejaculated with exocrine fluids secreted by accessory sex glands. Many studies have clarified the detailed structure and function of the male reproductive system, and have shown that various biologic controls, including genomics, epigenetics, and the neuroendocrine-immune system regulate proliferation, differentiation, and maturation of germ cells. In other words (1) genetic deletion or abnormalities, (2) aberration of DNA methylation and histone modifications, as well as small RNA dysfunction, and (3) neuroendocrine-immune disorders are involved in functional failure of the male reproductive system. In this article, we review these three factors for germ cell microcircumstance, especially focused on the immunoendocrine environment. In particular, the relation between factors protecting germ cells with strong auto-immunogenicity and opposite factors compromising this protection are discussed. Reductions in sperm count, concentration, and semen quality are serious problems in developed countries, although the causes are complex and remain unclear. The accumulation of basic knowledge regarding the structure, function, and regulation of the male reproductive system under various experimental conditions will be important to resolve these problems.
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Dai L, Endo D, Akiyama N, Yamamoto-Fukuda T, Koji T. Aberrant levels of histone H3 acetylation induce spermatid anomaly in mouse testis. Histochem Cell Biol 2014; 143:209-24. [DOI: 10.1007/s00418-014-1283-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/28/2014] [Indexed: 12/17/2022]
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Song N, Endo D, Koji T. Roles of epigenome in mammalian spermatogenesis. Reprod Med Biol 2013; 13:59-69. [PMID: 29699150 DOI: 10.1007/s12522-013-0167-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Accepted: 08/07/2013] [Indexed: 10/26/2022] Open
Abstract
Mammalian spermatogenesis is a successive process consisting of spermatogonial proliferation, spermatocytic meiosis, and spermiogenesis, representing the maturation of haploid spermatids. During the process, 25-75 % of the expected sperm yield is thought to be lost through apoptosis. In addition, spermatogenesis is considered to be a process undergoing successive heterochromatinization, finally reaching a complete condensed form in the sperm head. Thus, cell proliferation, differentiation and death may be strictly regulated by epigenetic factors in this process. This review describes the current understanding of the role of epigenome in spermatogenesis, especially focusing on the following aspects; DNA methylation, modification of histones, and small RNA function. These epigenetic factors affect each other and play a central role in events essential for spermatogenesis, fertilization and embryogenesis, through the regulation of gene expression, transposon activities, meiotic sex chromosome inactivation, histone remodeling and genome imprinting. Finally, a brief discussion of future avenues of study is highlighted.
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Affiliation(s)
- Ning Song
- Department of Histology and Cell Biology Nagasaki University Graduate School of Biomedical Sciences 1-12-4 Sakamoto 852-8523 Nagasaki Japan
| | - Daisuke Endo
- Department of Histology and Cell Biology Nagasaki University Graduate School of Biomedical Sciences 1-12-4 Sakamoto 852-8523 Nagasaki Japan
| | - Takehiko Koji
- Department of Histology and Cell Biology Nagasaki University Graduate School of Biomedical Sciences 1-12-4 Sakamoto 852-8523 Nagasaki Japan
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Song N, Liu J, An S, Nishino T, Hishikawa Y, Koji T. Immunohistochemical Analysis of Histone H3 Modifications in Germ Cells during Mouse Spermatogenesis. Acta Histochem Cytochem 2011; 44:183-90. [PMID: 21927517 PMCID: PMC3168764 DOI: 10.1267/ahc.11027] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Accepted: 06/29/2011] [Indexed: 11/22/2022] Open
Abstract
Histone modification has been implicated in the regulation of mammalian spermatogenesis. However, the association of differently modified histone H3 with a specific stage of germ cells during spermatogenesis is not fully understood. In this study, we examined the localization of variously modified histone H3 in paraffin-embedded sections of adult mouse testis immunohistochemically, focusing on acetylation at lysine 9 (H3K9ac), lysine 18 (H3K18ac), and lysine 23 (H3K23ac); tri-methylation at lysine 4 (H3K4me3) and lysine 27 (H3K27me3); and phosphorylation at serine 10 (H3S10phos). As a result, we found that there was a significant fluctuation in the modifications; in spermatogonia, the stainings for H3K9ac, H3K18ac, and H3K23ac were strong while that for H3K4me3 was weak. In spermatocytes, the stainings for H3K9ac, H3K18ac, H3K23ac, and H3K4me3 were reduced in the preleptotene to pachytene stage, but in diplotene stage the stainings for H3K18ac, H3K23ac, and H3K4me3 seemed to become intense again. The staining for H3K27me3 was nearly constant throughout these stages. In the ensuing spermiogenesis, a dramatic acetylation and methylation of histone H3 was found in the early elongated spermatids and then almost all signals disappeared in the late elongated spermatids, in parallel with the replacement from histones to protamines. In addition, we confirmed that the staining of histone H3S10phos was exclusively associated with mitotic and meiotic cell division. Based upon the above results, we indicated that the modification pattern of histone H3 is subject to dynamic change and specific to a certain stage of germ cell differentiation during mouse spermatogenesis.
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Affiliation(s)
- Ning Song
- Department of Histology and Cell Biology, Nagasaki University Graduate School of Biomedical Sciences
| | - Jie Liu
- Department of Prosthodontics, College of Stomatology, Jiamusi University
| | - Shucai An
- Department of General Surgery, First Affiliated Hospital, Medical College of Jiamusi University
| | - Tomoya Nishino
- Department of Histology and Cell Biology, Nagasaki University Graduate School of Biomedical Sciences
| | - Yoshitaka Hishikawa
- Department of Histology and Cell Biology, Nagasaki University Graduate School of Biomedical Sciences
| | - Takehiko Koji
- Department of Histology and Cell Biology, Nagasaki University Graduate School of Biomedical Sciences
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Arai H, Furusu A, Nishino T, Obata Y, Nakazawa Y, Nakazawa M, Hirose M, Abe K, Koji T, Kohno S. Thalidomide prevents the progression of peritoneal fibrosis in mice. Acta Histochem Cytochem 2011; 44:51-60. [PMID: 21614166 PMCID: PMC3096082 DOI: 10.1267/ahc.10030] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Accepted: 02/02/2011] [Indexed: 12/29/2022] Open
Abstract
Thalidomide is clinically recognized as a therapeutic agent for multiple myeloma and has been known to exert anti-angiogenic actions. Recent studies have suggested the involvement of angiogenesis in the progression of peritoneal fibrosis. The present study investigated the effects of thalidomide on the development of peritoneal fibrosis induced by injection of chlorhexidine gluconate (CG) into the mouse peritoneal cavity every other day for 3 weeks. Thalidomide was given orally every day. Peritoneal tissues were dissected out 21 days after CG injection. Expression of CD31 (as a marker of endothelial cells), proliferating cell nuclear antigen (PCNA), vascular endothelial growth factor (VEGF), α-smooth muscle actin (as a marker of myofibroblasts), type III collagen and transforming growth factor (TGF)-β was examined using immunohistochemistry. CG group showed thickening of the submesothelial zone and increased numbers of vessels and myofibroblasts. Large numbers of VEGF-, PCNA-, and TGF-β-positive cells were observed in the submesothelial area. Thalidomide treatment significantly ameliorated submesothelial thickening and angiogenesis, and decreased numbers of PCNA- and VEGF-expressing cells, myofibroblasts, and TGF-β-positive cells. Moreover, thalidomide attenuated peritoneal permeability for creatinine, compared to the CG group. Our results indicate the potential utility of thalidomide for preventing peritoneal fibrosis.
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Affiliation(s)
- Hideyuki Arai
- Second Department of Internal Medicine, Nagasaki University School of Medicine
| | - Akira Furusu
- Second Department of Internal Medicine, Nagasaki University School of Medicine
| | - Tomoya Nishino
- Second Department of Internal Medicine, Nagasaki University School of Medicine
- Department of Histology and Cell Biology, Nagasaki University Graduate School of Biomedical Sciences
| | - Yoko Obata
- Second Department of Internal Medicine, Nagasaki University School of Medicine
- Career Development Center for Medical Doctors, Nagasaki University Hospital
| | - Yuka Nakazawa
- Second Department of Internal Medicine, Nagasaki University School of Medicine
| | - Masayuki Nakazawa
- Second Department of Internal Medicine, Nagasaki University School of Medicine
| | - Misaki Hirose
- Second Department of Internal Medicine, Nagasaki University School of Medicine
| | | | - Takehiko Koji
- Department of Histology and Cell Biology, Nagasaki University Graduate School of Biomedical Sciences
| | - Shigeru Kohno
- Second Department of Internal Medicine, Nagasaki University School of Medicine
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Shin M, Larsson LI, Hougaard DM, Fujiwara K. Daunomycin accumulation and induction of programmed cell death in rat hair follicles. Cell Tissue Res 2009; 337:429-38. [DOI: 10.1007/s00441-009-0840-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Accepted: 06/30/2009] [Indexed: 02/05/2023]
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Ohara K, Shin M, Nakamuta H, Larsson LI, Hougaard DM, Fujiwara K. Immunocytochemical studies on the distribution pattern of daunomycin in rat gastrointestinal tract. Histochem Cell Biol 2007; 128:285-90. [PMID: 17661066 DOI: 10.1007/s00418-007-0314-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2007] [Accepted: 07/03/2007] [Indexed: 11/28/2022]
Abstract
The cancer drug daunomycin is used in treatment of leukemia but possesses severe side effects that involve the gastrointestinal tract. We therefore used a newly developed immunocytochemical procedure to determine the distribution of DM in the gastrointestinal tracts of rats after i.v. injection. Two hours after injection, DM was diffusely distributed in nuclei and most parts of the cytoplasm of intestinal epithelial cells. The cytoplasmic immunoreactivity for DM was most pronounced in small granules of the apical cytoplasm. Sixteen hours after injection, DM immunostaining was by and large absent in the villous epithelium but persisted in the intestinal crypts. In addition, staining was also detected in endothelial cells, scattered cells of the lamina propria and in smooth muscle cells. After 5 days, only little staining for DM remained. Similar findings were made in the colon. In the gastric mucosa, DM accumulation persisted at 16 h in some glandular cells but was lost from the surface epithelium. No staining was detected in saline-injected control rats. The distribution of DM accumulation correlated partially with the distribution of apoptotic cells as detected by the TUNEL procedure. Our results pinpoint that DM may exert prolonged effects on glandular and regenerative cells of the gastrointestinal tract-an observation that may explain the gastrointestinal toxicity of the drug. It seems possible that DM accumulation in surface epithelial cells is rapidly cleared through drug transporters.
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Affiliation(s)
- Koji Ohara
- Department of Applied Life Science, Faculty of Biotechnology and Life Science, Sojo University, Ikeda 4-22-1, Kumamoto, 860-0082, Japan
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Hishikawa Y, Tamaru N, Ejima K, Hayashi T, Koji T. Expression of keratinocyte growth factor and its receptor in human breast cancer: its inhibitory role in the induction of apoptosis possibly through the overexpression of Bcl-2. ACTA ACUST UNITED AC 2005; 67:455-64. [PMID: 15781986 DOI: 10.1679/aohc.67.455] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Keratinocyte growth factor (KGF), a mesenchymal cell derived paracrine growth factor that regulates normal epithelial cell proliferation, appears to be an essential mediator of steroids in various reproductive organs. The present study was designed to determine the expression and role of KGF and its receptor (KGFR) in human breast carcinoma tissues by immunohistochemistry. We also compared the results with the expression of estrogen receptor alpha(ERalpha), ERbeta, the proliferative activity assessed by the labeling index (LI) for the Ki-67 antigen, apoptotic frequency assessed by terminal dUTP nick end-labeling (TUNEL) index, and the expression of Bcl-2. All of KGF-positive cases were ERalpha- positive (p<0.05), but not that of ERbeta, while all of KGFR-positive cases were ERbeta-positive (p<0.05), but not that of ERalpha. The specimens with the coexpression of KGF and KGFR significantly correlated with a lower TUNEL index (p<0.05), but not with Ki-67 LI in breast cancer tissues. Further analysis at the cellular level revealed that Bcl-2 was colocalized in KGFR-positive cells, and these cells were almost negative for TUNEL staining. Bcl-2-positive cells were also associated with ERbeta, as expected. Therefore, the results indicate that ERalpha may be involved in KGF expression, and that the coexpression of KGF and KGFR may play an inhibitory role in the induction of apoptosis possibly through the up-regulation of Bcl-2 expression in human breast cancer.
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MESH Headings
- Adult
- Aged
- Apoptosis
- Breast Neoplasms/metabolism
- Breast Neoplasms/pathology
- Carcinoma, Ductal, Breast/metabolism
- Carcinoma, Ductal, Breast/pathology
- Carcinoma, Lobular/metabolism
- Carcinoma, Lobular/pathology
- Cell Proliferation
- Estrogen Receptor alpha/metabolism
- Estrogen Receptor beta/metabolism
- Female
- Fibroblast Growth Factor 7
- Fibroblast Growth Factors/genetics
- Fibroblast Growth Factors/metabolism
- Gene Expression Regulation, Neoplastic
- Humans
- Immunohistochemistry
- Keratinocytes/cytology
- Keratinocytes/metabolism
- Ki-67 Antigen/metabolism
- Middle Aged
- Proto-Oncogene Proteins c-bcl-2/metabolism
- Receptor, Fibroblast Growth Factor, Type 2
- Receptors, Fibroblast Growth Factor/metabolism
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Affiliation(s)
- Yoshitaka Hishikawa
- Division of Histology and Cell Biology, Department of Developmental and Reconstructive Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
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An S, Hishikawa Y, Koji T. Induction of cell death in rat small intestine by ischemia reperfusion: differential roles of Fas/Fas ligand and Bcl-2/Bax systems depending upon cell types. Histochem Cell Biol 2005; 123:249-61. [PMID: 15765213 DOI: 10.1007/s00418-005-0765-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2004] [Accepted: 01/03/2005] [Indexed: 10/25/2022]
Abstract
Although ischemia reperfusion (I/R) induces apoptotic damage of mammalian small intestine, the molecular mechanism is largely unknown. We investigated the appearance of apoptosis at various time-points (0-24 h) of reperfusion after 1-h ischemia and the expression of various apoptosis-related proteins, such as Bcl-2, Bax, Fas, Fas ligand (FasL), activated caspase-3, and cytochrome c, immunohistochemically in rat small intestine. As assessed by TUNEL and electron microscopy, apoptotic cells were increased at 3 h of reperfusion in all intestinal parts (villous epithelium, crypt epithelium, and stroma of intestine). Moreover, the TUNEL-positive cells in the stroma were later identified as T cells. The expression of Fas and FasL as well as activated caspase-3 was markedly increased at 3 h of reperfusion in the stroma. In the villous epithelium, a transient decrease in Bcl-2 expression was found while in the crypt epithelium, Fas expression was induced. Finally, intraperitoneal injection of leupeptin (an SH-protease inhibitor) after I/R resulted in a significant inhibition of the induction of apoptosis in the stroma and crypt epithelium. Our results indicate that the triggering molecules of apoptosis in the I/R rat small intestine may vary depending on cell type and that the use of a broad-spectrum protease inhibitor may reduce intestinal damage.
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Affiliation(s)
- Shucai An
- Division of Histology and Cell Biology, Department of Developmental and Reconstructive Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-12-4, Sakamoto, Nagasaki 8528523, Japan
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Dündar M, Koçak I, Culhaci N, Erol H. Determination of apoptosis through bax expression in cryptorchid testis: an experimental study. Pathol Oncol Res 2005; 11:170-3. [PMID: 16195771 DOI: 10.1007/bf02893394] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2005] [Accepted: 09/07/2005] [Indexed: 11/30/2022]
Abstract
The aim was to determine the expression of Bax in germ cells of rats with unilateral experimental cryptorchidism, and to evaluate the role of apoptosis in germ cell loss. Twenty-one prepubertal rats were randomly subdivided into three groups after the execution of the left cryptorchidism model. Group 1 (n=8), group 2 (n=6) and group 3 (n=7) rats were killed at the end of the first, second and third month, respectively. Bax expression was assessed in Sertoli cells, spermatogonia and spermatocytes by immunohistochemistry. Percentages of Bax expression in spermatocytes and spermatogonia were decreased in the left testicles in the 2nd and 3rd months compared to results obtained in the 1st month (p<0.05). Percentage of Bax expression in the left testicles of group 1, at the level of both spermatogonia and spermatocytes was higher than that in the right one (p<0.05). However, in groups 2 and 3, the higher Bax expression on the left side was only seen in the spermatocytes (p<0.05). In all groups, the mean weight of the left testicle was lower than that of the scrotal counterpart where the difference was significant only in groups 1 and 3 (p<0.05). The weight of the left and right testicles was increasing with time. In this model of cryptorchidism, the affected testis had a decreased weight compared to the normal one. Based on the increased Bax expression, we think that apoptosis may play a role in the germ cell loss.
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Affiliation(s)
- Mehmet Dündar
- Department Urology, Medical School, Adnan Menderes University, Aydin 09100, Turkey.
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Sakai Y, Noce T, Yamashina S. Cleavage-like cell division and explosive increase in cell number of neonatal gonocytes. Dev Growth Differ 2004; 46:15-21. [PMID: 15008851 DOI: 10.1111/j.1440-169x.2004.00724.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Based on previous conventional quantitative observations of rat testes, it was proposed that large numbers of gonocytes degenerate after birth and this notion was widely accepted. However, many studies show that neonatal gonocytes display high levels of mitotic activity. In order to resolve the apparent contradiction of increased mitotic activity in gonocytes despite a decrease in their numbers at the neonate stage, quantitative analysis using a marker of suitably higher resolution is required. It has been shown that the vasa protein could be used as a marker of germ cells. In this study, quantitative changes in gonocytes were re-examined using a germ-cell-specific marker in order to delineate more clearly the process of development from gonocytes to spermatogonia after birth. The vasa-positive cells, which correspond to gonocytes and spermatogonia, increased exponentially after birth. This observation suggests that all gonocyte divide actively after birth and do not degenerate as previously believed. Surprisingly, the cell volume of gonocytes decreased during their division. The largest population size was 2000-4000 micro3 at day 2, 1000-2000 micro3 at day 4 and 500-1000 micro3 at day 6. This finding suggests that gonocytes divide in a similar way to cleavage, which can be considered a special mode of fertilized eggs. Judging from the growth of seminiferous tubules and the degree of volume reduction, 60% of the contribution rate is estimated to be due to ordinal cell growth, and 40% due to volume reduction as in cleavage of a fertilized egg. This unique cleavage-like division may contribute to the supply of large numbers of spermatogonia.
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Affiliation(s)
- Yasuhiro Sakai
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara 228-8555, Japan.
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Koji T, Hishikawa Y. Germ cell apoptosis and its molecular trigger in mouse testes. ARCHIVES OF HISTOLOGY AND CYTOLOGY 2003; 66:1-16. [PMID: 12703549 DOI: 10.1679/aohc.66.1] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Germ cell apoptosis is very common during various stages of mammalian testicular development. However, our understanding of the mechanisms underlying male germ cell apoptosis is still limited. This review firstly covers the general features of germ cell death in normal testes of fetal, neonatal, and adult mice from electron microscopy (EM) and terminal dUTP nick-end labeling (TUNEL) staining. The issue of whether the Fas and Fas ligand (FasL) system and/or the Bax and Bcl-2 system is involved in the induction of germ cell apoptosis in normal and damaged testes will then be addressed, including a special consideration of the ischemia-reperfusion model, the endocrine disruptor-treated model, and others. Finally, this review will propose that the process of normal spermatogenesis seems skillfull in taking advantage of apoptotic processes of germ cells and that different molecular pathways may be triggered to induce male germ cell apoptosis, depending upon the physiological and pathological states of germ cells.
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Affiliation(s)
- Takehiko Koji
- Department of Histology and Cell Biology, Nagasaki University School of Medicine, Nagasaki, Japan.
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Tsutsumi Y, Kamoshida S. Pitfalls and Caveats in Histochemically Demonstrating Apoptosis. Acta Histochem Cytochem 2003. [DOI: 10.1267/ahc.36.271] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Yutaka Tsutsumi
- Department of Pathology, Fujita Health University School of Medicine
| | - Shingo Kamoshida
- Department of Pathology, Fujita Health University School of Medicine
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