• Development and Reproduction
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• v.14 no.2
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• pp.99-105
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• 2010

The seminiferous epithelium, with its division into 12 spermatogenic stages in the mouse, is a very complex tissue. Glutathione peroxidase (GPx) is a representative antioxidant enzyme that is capable of reducing organic hydroperoxides to their corresponding hydroxyl compounds utilizing glutathione and is related to the mammalian spermatogenesis. In this study, a real-time PCR was performed in the stage-specific seminiferous tubules of mouse testes excised by a laser capture microdissection (LCM) in order to quantitate the expression levels of a series of GPx genes including cytosolic GPx (cGPx), gastrointestinal GPx (GI-GPx), plasma GPx (pGPx), and phospholipid hydroperoxide GPx (PHGPx). Frozen sections (10 ${\mu}m$) were obtained from normal adult mouse testes. LCM was used to capture all the cells that were grouped into stages I-V, VII-VIII, and IX-XI in cross-sections of seminiferous tubules. The expression level of PHGPx mRNA was remarkably higher than those of other GPx mRNAs in mouse testes. During spermatogenesis, the expressions of GI-GPx, pGPx, and PHGPx mRNAs were highest on stages VII-VIII, began to decrease after stage XI, and showed a lowest level on stage I-V. However, the expressions of cGPx mRNA were highest on stages VII-VIII, and showed a lowest level on stage XI-XI. These findings indicate that GPx genes are expressed differentially on mouse spermatogenesis and also LCM can be an useful tool in cellular quantitative analysis of testes.

• Development and Reproduction
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• v.10 no.1
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• pp.1-7
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• 2006

Ovarian follicular atresia in mammals is finely regulated by gonadotropins and sex steroid hormones. It is well known that granulosa cell pyknosis is a common cytological feature of atretic follicles in the ovary. The present study hypothesized that granulosa cell pyknosis during follicular atresia might be related to apoptotic process and associated with caspase-3 activation. Healthy (normal) and atretic follicles were isolated from porcine ovaries based on macro-morphological criteria. Isolated follicles were either processed for histological observation or used for collection of granulosa cells by aspiration. Hoechst 33258 staining of the cells showed a significantly higher number of fragmented nuclei, a typical morphological feature of apoptotic cell, in granulosa cells from atretic follicles than those from healthy follicles. In addition, the rate of cell death was significantly higher in granulosa cells from atretic follicles than healthy follicles, as measured by flow-cytometric cell cycle analysis. In situ detection of apoptotic cells by TUNEL revealed that apoptosis was mostly restricted to granulosa cells in follicles. Theca cells were TUNEL-negative. Finally, it has been shown by caspase-3 activity assay that granulosa cells from atretic follicles retain a higher caspase-3 activity compared to healthy follicles. Taken together, it is suggested that granulosa cell degeneration during folliclar atresia occurs by caspase-3-dependent apoptotic fashion.

• Development and Reproduction
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• v.11 no.1
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• pp.49-54
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• 2007

Ethane 1,2-dimethane sulfonate(EDS), a toxin which specifically kills Leydig cells(LC), has been widely used to prepare the reversible testosterone(T) depletion rat model. In the present study, we monitored the gene expression profiles of pituitary gonadotropins, LH and FSH, up to 7 weeks after EDS injection. Adult male Sprague-Dawley rats($300{\sim}350\;g$ B.W.) were injected with a single dose of EDS(75 mg/kg i.p.) and sacrificed on weeks 0, 1, 2, 3, 4, 5, 6 and 7. Total RNAs were purified from each pituitary, and the message levels of common alpha subunit($C{\alpha}$) of pituitary glycoprotein hormones, LH beta subunit($LH{\beta}$), FSH beta subunit($FSH{\beta}$) and GnRH receptor(GnRH-R) were evaluated by semi-quantitative RT-PCRs. The message levels of $C{\alpha}$ increased sharply during weeks 1-4, then return to the control level on week 5. The mRNA levels of $LH{\beta}$ were elevated after week 2, reached the peak at week 4, then declined to the control level after week 5. The message levels of $FSH{\beta}$ were elevated after week 2, reached the peak at week 3, then declined to the nadir at week 5. Similarly, the mRNA levels of GnRH-R were elevated after week 2, reached the peak at week 3, then gradually declined to the control level after week 5. The present study indicated that EDS treatment could induce reversible alterations in the transcriptional activities of gonadotropin subunits and GnRH-R in the anterior pituitary from male rats. EDS injection model might be useful to understand the mechanism of hormonal regulation of hypothalamus- pituitary neuroendocrine axis in male rats.

• Korean Journal of Poultry Science
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• v.8 no.1
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• pp.1-5
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• 1981

In trying to predict the effect of genetics on the broiler in the year 2000, this is a relatively short period of time as far as broiler genetics in concerned. Modern broiler genetics started around 1945 and tremendous gains when made in past 35 years. Futher improvements on broiler will depend on the evolution and revolution: 1. Evolution: (1) Growth rate has been made 4-5% per year. (2) Feed conversion has improved approximately 1% per year. (3) Abdominal fat is becoming a major complaint in broiler. (4) Because of the changing life-style, broiler meat sales in the future will be more and more in cut-up form. (5) Breeding for stress resistance and selection for docile temperament can be important in order to funker improve fled efficiency. (6) In female parent stock, reproduction characteristics are in many can negatively correlated with the desired broiler traits. (7) Egg production and hatchability in moot commercial parent nod m at a fairly high level. (8) In male parent stock, the heavier and mon super-meat-type male lines are desired to Product better broilers. 2. Revolution: Trying to forecast revolutionary change in broiler genetics is highly speculative, as sudden change are aften unpredictable. (1) Species hybridization, such as a turkey-chicken cross (2) Biochemical tools, such as blood typing. (3) Mutation breeding by radiation or chemical mutagentia. (4) Broiler breeding would be to change the phenotypic appearance by single gene, such as naked, wingless. (5) Changes in production techniques. such as growing in cage or growing in filtered air positive pressure houses.

• Korea journal of population studies
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• v.29 no.2
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• pp.53-88
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• 2006

The major aim of this paper is to develop a hypothetical set of age-specific fertility rates which are logically derived and reasonably accurate in the projection of future population. The first procedure is to select a generalized log-gamma distribution model, which includes Coale-McNeil nuptiality model, in order to estimate and project a set of age-specific fertility rates by birth cohort and birth order. The second is to apply the log-gamma model with an empirical adjustment to the actual data to estimate and project the future fertility rates for relatively young birth cohorts who did not complete their reproductive career. This study reconstructs or translates a set of cohort age-specific fertility rates into a set of period age-specific fertility rates which must be hypothesized in order to establish the broader framework of future population projection. For example, the fertility at age 20 in the year of 2020 is the fertility at age 20 for the cohort born in 1990, while the fertility at age 21 in the year of 2020 is the fertility at 21 for the cohort born in 1989. In turn, once a set of age-specific fertility rates for the cohorts who were born up to the year of 2010, it is possible for one to establish an hypothetical set of period age-specific fertility rates which will be needed to project the future population until the year of 2055. The difference in the hypothetical system of age-specific fertility rates between this study and the 2005 special population projection comes from the fact that the fertility estimation/projection model used in this study was skillfully exploited to reflect better actual trend of fertility decline caused by rise in marriage age and increasing proportion of those who remain single until their end of reproduction. In this regard, this paper argues that the set of age-specific fertility rates derived from this study is more logical and reasonably accurate than the set of those used for the 2005 special projection. In the population projection, however, the fundamental issue of the hypothetical setting of age-specific fertility rates in relation to the fertility estimation/projection model is about how skillfully one can handle the period effects. It is not easy for one to completely cope with the problem of period effects except for the a minor period adjustment based on recent actual data, along with the given framework of a cohort-based fertility estimation/projection model.

• Development and Reproduction
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• v.11 no.2
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• pp.111-119
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• 2007

Differentiation of cells can be induced through modulation of endogenous regulators using exogenous factors. Useful transfection systems to transport a specific exogenous regulator into cell have been tried but still there are many obstacles to overcome. In this study, we examined the transfection efficiency of cell permeable peptides (CPPs) in mouse embryonic stem cell under the various conditions. To identify the CPP-mediated translocation of a protein, we employed recombinant CPP-enhanced green fluorescent protein (EGFP). Viability of R1 cells was different between experimental groups depending on the kind of CPP and the concentration of CPP-EGFP. Translocation of CPP-EGFPs into the R1 cells was not detected until 30 min after CPP-EGFPs treatment in all groups. After 1 hr, translocation of pEP-1-EGFP-N was detected, but it could not be detected in the other group. Transfection of pEP-1EGFP-N was independent on its concentration. The time course did not show saturation even after 24 hr in pEP-1-EGFP-N. These results showed that the permeability depended on the kind of CPP and the location of His-tag in the case of examined CPPs, and did not need biological energy. On summary, the efficiency of transfection of CPP-EGFP depends on the CPP sequences but the culture time is not a key factor in transfection for the mouse embryonic stem cell. For the future studies to improve the efficiency of translocation of protein into embryonic stem cells, it is needed to develop modified CPP or mediator. The studies would be very useful to induce the differentiation of embryonic stem cells.

• Development and Reproduction
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• v.5 no.1
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• pp.23-33
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• 2001

When mammalian oocytes ovulate into the oviduct, associating follicular fluid components are exposed to the oviductal environment, possibly resulting in the mutual interaction between fillicu1ar and oviductal fluids. In the Present study, we have demonstrated for the first time that components of fallicular fluid could be modified by the oviductal fluid. Gelatin zymographic analyses of human follicular fluid (hFF) obtained from IVF patients showed consistently the presence of 110 kDa gelatinase (GA110) in addition to many bands among which 62 kDa gelatinase was predominant. Addition of EDTA or phenanfhroline to the gelatinase substrate buffer during gel incubation abolished GA110 band whereas phenylmethylsulffnyl fluoride (PMSF) did not. In contrast, bovine oviductal fluid(bOF) exhibited only 62 kDa gelatinase. Surprisingly, when bOF was added to hFF in 1:1 ratio and then the mixture was incubated for 3 h at 37$^{\circ}$C, GA110 of hFF disappeared. Disappearance of GA110 by bOF was observed even within 30 min after mixing with hFF. Addition of aminophenylmercuric acetate (APMA) to hFF also abolished enzymatic activity of GA110 but increased the activityof 62 kDa gelatinase. However, APMA abolished many other gelatinases as well unlike bOF. Interestingly, treatment of hFF with EDTA for 3 h remarkably increased the enzymatic activity of GA110 but not that of other gelatinases. Addition of phenanthroline, PMSF or soybean trypsin inhibitor (SBTI) did not affect overall gelatinase activities. Again, addition of bOF to the hFF pretreated with any of the above proteinase inhibitors abolished the appearance of GA110. Human serum also showed GAI 10 of which activity was greatlyenhanced by EDTA treatment. Similar to hFF, serum GA110 also disappeared by the addition of bOF. Human granulosa cell homogenate did not reveal any appreciable gelatinase activity except 92 kDa gelatinase. Anti-human gelatinase A antibody reacted with 62 kDa gelatinase of hFF. Based upon these results, it is concluded that bOF could selectively degrade an isoform of gelatinase A present in hFF and human serum.

• Journal of Science of Art and Design
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• v.11
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• pp.221-249
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• 2007

Today, photography is facing to the crisis of identity and dilemma of ontology from the digital imaging process in the new technology form. It is very important points to say rethinking of the traditional photographic medium, that has changed the way we view the world and ourselves is perhaps an understatement and that photography has transformed our essential understanding of reality. Now, no longer are photographic images regarded as the true automatic recording, innocent evidence and the mirror to the reality. Rather, photography constructs the world for our entertainment, helping to create the comforting illusions by which we live. The recognition that photographs are not constructions and reflections of reality, is the basis for the actual presence within the contemporary photographic world. It is shock. This thesis's aim is to look for the problems of photographic identity and ontological crisis that is controlling and regulating digital photographic imagery, allowing the reproduction of the electronic simulations era. Photography loses its special aesthetic status and becomes no more true information and, exclusively evidence by traditional film and paper that appeared both as a technological accuracy and as a medium-specific aesthetic. The result, photography is facing two crises, one is the photographic ontology(the introduction of computerized digital images) and the other is photographic epistemology(having to do broader changes in ethics, knowledge and culture). Taken together, these crises apparently threaten us with the death of photography, with the 'end' of photography and the culture it sustains. The thesis's meaning is to look into the dilemma of photography's ontology and epistemology, especially, automatical index and digital codes from its origin, meaning, and identity as the technological medium. Thus, in particular, thesis focuses on the analog imagery presence, from the nature in the material world, and the digital imagery presence from the cultural situations in our society. And also thesis's aim is to examine the main issues of the history of photography has been concentrated on the ontological arguments since the discovery of photography in 1839. Photography has never been only one static technology form. Rather, its nearly two centuries of technological development have been marked by numerous, competing of technological innovation and self revolution from the dual aspects. This thesis examines recent account of photography by the analysis of the medium's concept, meaning, identity between film base image and digital base image from the aspects of photographic ontology and epistemology. Thus, the structure of thesis is fairy straightforward to examine what appear to be two opposing view of photographic conditions and ontological situations. Thesis' view contrasts that figure out the value of photography according to its fundamental characteristic as a medium. Also, it seeks a possible solution to the dilemma of photographic ontology through the medium's origin from the early years of the nineteenth century to the raising questions about the different meaning(analog/digital) of photography, now. Finally, this thesis emphasizes and concludes that the photographic ontological crisis reflects to the paradoxical dynamic structure, that unsolved the origins of the medium, itself. Moreover, even photography is not single identity of the photographic ontology, and also can not be understood as having a static identity or singular status from the dynamic field of technologies, practices, and images.

• Reproductive and Developmental Biology
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• v.28 no.1
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• pp.21-27
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• 2004

This study was conducted to investigate the developmental ability of caprine embryos after somatic cell interspecies nuclear transfer. Recipient bovine and porcine oocytes were obtained from slaughterhouse and were matured in vitro according to established protocols. Donor cells were obtained from an ear-skin biopsy of a caprine, digested with 0.25% trypsin-EDTA in PBS and primary fibroblast cultures were established in TCM-199 with 10% FBS. The matured oocytes were dipped in D-PBS plus 10% FBS ＋ 7.5 $\mu$ g/ml cytochalasin B and 0.05M sucrose. Enucleation were accomplished by aspirating the first polar body and partial cytoplasm which containing metaphase II chromosomes using a micropipette with an out diameter of 20∼30 $\mu$m. A Single donor cell was individually transferred into the perivitelline space of each enucleated oocyte. The reconstructed oocytes were electric fusion with 0.3M mannitol fusion medium. After the electrofusion, embryos were activated by electric stimulation. Interspecies nuclear transfer embryos with bovine cytoplasts were cultured in TCM-199 medium supplemented with 10% FBS including bovine oviduct epithelial cells for 7∼9 day. And porcine cytoplasts were cultured in NCSU-23 medium supplemented with 10% FBS for 6 ∼8 day at $39^{\circ}C, 5% CO_2 $in air. Interspecies nuclear transfer by recipient bovine oocytes were fused with electric length 1.95 kv/cm and 2.10 kv/cm. There was no significant difference between two electric length in fusion rate(47.7 and 44.6%) and in cleavage rate(41.9 and 54.5%). Using electric length 1.95 kv/cm and 2.10 kv/cm in caprine-porcine NT oocytes, there was also no significant difference between two treatments in fusion rate(51.3 and 46.1%) and in cleavage rate(75.0 and 84.9%). The caprine-bovine NT oocytes fusion rate was lower(P＜0.05) in 1 pulse for 60 $\mu$sec(19.3%), than those from 1 pulse for 30 $\mu$sec(50.8%) and 2 pulse for 30 $\mu$sec(31.0%). The cleavage rate was higher(P＜0.05) in 1 pulse for 30 $\mu$sec(53.3%) and 2 pulse for 30 $\mu$sec(50.0%), than in 1 pulse for 60 $\mu$sec(18.2%). The caprine-porcine NT oocytes fusion rate was 48.1% in 1 pulse for 30 $\mu$sec, 45.2% in 2 pulse for 30 $\mu$sec and 48.6% in 1 pulse for 60 $\mu$sec. The cleavage rate was higher(P＜0.05) in 1 pulse for 30 $\mu$sec(78.4%) and 1 pulse for 60 $\mu$sec(79.4%), than in 2 pulse for 30 $\mu$sec(53.6%). In caprine-bovine NT embryos, the developmental rate of morula and blastocyst stage embryos were 22.6% in interspecies nuclear transfer and 30.6% in parthenotes, which was no significant differed. The developmental rate of morula and blastocyst stage embryos with caprine-porcine NT embryos were lower(P＜0.05) in interspecies nuclear transfer(5.1%) than parthenotes(37.4%).

• Development and Reproduction
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• v.13 no.4
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• pp.257-264
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• 2009

A neurotoxin, 6-hydroxydopamine (6-OHDA) has been widely used to create animal model for Parkinson's disease (PD) due to its specific toxicity against dopaminergic (DA) neurons. Since DA signals modulate a broad spectrum of CNS physiology, one can expect profound alterations in neuroendocrine activities of both PD patients and 6-OHDA treated animals. Limited applications of 6-OHDA injection model, however, have been made on the studies of hypothalamuspituitary neuroendocrine circuits. The present study was performed to examine whether blockade of brain catecholamine (CA) biosynthesis with 6-OHDA can make any alteration in the transcriptional activities of hypothalamus-pituitary hormone genes in adult male rats. Three-month-old male rats (SD strain) were received 6-OHDA ($200{\mu}g$ in $10{\mu}\ell$ of saline/animal) by intracerebroventricular (icv) injection, and sacrificed after two weeks. To determine the mRNA levels of hypothalamuspituitary hormone genes, total RNAs were extracted and applied to the semi-quantitative RT-PCRs. The mRNA levels of tyrosine hydroxylase (TH), the rate-limiting enzyme for the catecholamine biosynthesis, were significantly lower than those from the control group (control:6-OHDA=1:0.72${\pm}$0.02AU, p<0.001), confirming the efficacy of 6-OHDA injection. The mRNA levels of gonadotropin-releasing hormone (GnRH) and corticotropin releasing hormone (CRH) in the hypothalami from 6-OHDA group were significantly lower than those from the control group (GnRH, control:6-OHDA=1:0.39${\pm}$0.03AU, p<0.001; CRH, control:6-OHDA=1:0.76${\pm}$0.07AU, p<0.01). There were significant decreases in the mRNA levels of common alpha subunit of glycoprotein homones (Cg$\alpha$), LH beta subunit (LH-$\beta$), and FSH beta subunit (FSH-$\beta$) in pituitaries from 6-OHDA group compared to control values (Cg$\alpha$, control:6-OHDA=1:0.81${\pm}$0.02AU, p<0.001; LH-$\beta$, control:6-OHDA=1:0.68${\pm}$0.04AU, p<0.001; FSH-$\beta$, control:6-OHDA=1:0.84${\pm}$0.05AU, p<0.001). Similarly, the level of adrenocorticotrophic hormone (ACTH) transcripts from 6-OHDA group was significantly lower than that from the control group (control: 6-OHDA=1:0.86${\pm}$0.04AU, p<0.01). The present study demonstrated that centrally injected DA neurotoxin could downregulate the transcriptional activities of the two hypothalamus-pituitary neuroendocrine circuits, i.e., GnRH-gonadotropins and CRH-ACTH systems. These results suggested that hypothalamic CA input might affect on the activities of gonad and adrenal through modulation of hypothalamus-pituitary function, providing plausible explanation for frequent occurrence of sexual dysfunction and poor stress-response in PD patients.