• Korean Journal of Ecology and Environment
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• v.46 no.3
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• pp.395-408
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• 2013

Environmental condition can induce changes in early life-history traits in order to maximise the ecological fitness. Here I investigated how temperature change and variation in human aquatic activity/behaviour affect early life-history consequences in fish using a dynamic-state-dependent model. In this study, I developed a general fish's life-history model including three life-history states depend-ing on foraging activity, such as body mass, mass of reproductive tissue (i.e., gonadal development) and accumulated stress (i.e., cellular or physiological damage). I assumed the level of foraging activity maximises reproductive success-ultimately, fitness. The model predicts that growth rate, development of reproductive tissues and damage accumulation are greater in higher temperature whereas higher human aquatic activity rapidly reduced the growth rate and development of reproductive tissue and increased damage accumulation. While higher foraging activity in higher temperature is less affected by human aquatic activity, the foraging activity in lower temperature rapidly declined with human aquatic activity. Moreover, lower survival rate in higher temperature or human aquatic activity was independent on mortality rate due to human aquatic activity or mortality rate when foraging activity, respectively. However, the survival rate in lower temperature or human aquatic activity was dependent on these mortality rates. My findings suggest that including of early life-history traits in relation to climate-change and human aquatic activity on the analysis may improve conservation plan and health assessment in aquatic ecosystem.

• The Korean Journal of Malacology
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• v.31 no.1
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• pp.21-26
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• 2015

This study histologically describes the gonadal development and reproductive cycle of the abalone, Haliotis discus discus inhabiting Jeju Island of Korea. Gonads displayed histologically definitive seasonal changes. The gonad index (GI) of both females and males was the highest (3.2 and 3.3) in September and was the lowest (1.7 and 1.4) in January and February. Egg diameter increase from early stage in March and reach about $180{\mu}m$ to ripe stage in August. The condition index (CI) was highest in July and lowest in May. The pattern of changes in the GI, egg diameter and CI were similar to the pattern of seasonal changes in gonadal tissues. The female ratio (F/F + M) was 59% (n = 182:127). The reproductive cycle was divided into an inactive stage (January-February), early active stage (March-April), late active stage (May-July), ripe stage (August-October) and spent and degenerative stage (November-January). The main spawning period of H. discus discus was August to October at Jeju Island in 2014.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.2
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• pp.198-203
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• 1999

Gonadal development and reproductive cycle off Gomphina melanaegis collected in the coastal waters of Chumunjin, Korea were investigated monthly from April 1996 to April 1997. G. melanaegis was dioecious, The gonads were located between the digestive diverticula and muscle tissues of the foot, The ovary was composed of a number of ovarian sacs, and the testis was composed of several testicular tubules. The flesh weight rate was reached the maximum in August ($23.0\%$), and then decreased to $19.8\%$ in September. In March, the value was reached the minimum ($17.8\%$) and then increased, The size of mature oocyte was ranged $50\~60\mu$m in diameter and had a germinal vesicle with a nucleolus. Mature oocyte contained a large number of yolk granules and lipid granules in its cytoplasm. The spermatozoon was consisted of a conical nucleus with acrosome, a middle piece containing four mitochondria and proximal and distal centrioles, and a flagellum, Sex ratio (male/female) and minimum size for sexual maturation of G. melanaegis were 0.79 and about 25 mm in shell length, respectively. The reproductive cycle could be classified into five succesive stages: multiplicative (December to March), growing (April and May), mature(June), sprawning (July and August), and degenerative and resting (September to November) stages.

• The Korean Journal of Zoology
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• v.39 no.4
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• pp.337-351
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• 1996

Melatonin Is a multifunctional hormone secreted from the pineal gland in the middle of cerebrum and cerebellum. Its synthesis and release reflect photopedod;Photopedod is a yearly predictable ambient factor that most animals utilize as an environmental cue for maximum survival. Hamsters maintaln reproductive activity in summer during which day length exceeds night time. Upon the advent of autumnal equinox they undergo gonadal regression. The photoperiodic effects are prevented by removal of the pineal gland and restored by the timed repiacument of melatonin. The results suggest that melatonin constitutes part of control mechanism whereby environmental information is transduced to neuroendocrine signal responsIble for the functional integrity of the reproductive system. From the studies for the action site of melatonin following the treatment of photopedod or melatonin in the lesion of a spedflc portion of hypothalamus, suprachiasmatic nuclei and pars tuberalis are shown to be a consensus site for melatonIn. The action of melatonin. In the regulation of reproduction is largely unknown. It is mainly due to the lack of acute effect of melatonin on gonadotropin secretion. However, reduction of the gonadotropln release and augmentation of the hypothalamic gonadotropin-releasing hormone (GnRH) content by long-term treatment of melatonln Indicate that constant presence of melatonln may partidpate in the regulation of sexual activity via the GnRH neuronal system. The action mechanism by which melatonin exerts Its effect on GnRH neuron needs to be eluddated. The inability of opiold analogues to affect the reproductive hormones in sexually regressed animals by inhibftory photopedod and melatonin suggests that the opioldergic neuron may be a prime intervening mediator. Recent cloning of melatonin receptor will contribute to investigate its anatomical Identification and the action mechanism of melatonin on target tissues at the molecular level.

• The Korean Journal of Malacology
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• v.22 no.1 s.35
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• pp.27-38
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• 2006

We investigated the reproductive cycle with gonad developmental phases of Solen grandis by histological observations. Seasonal changes in biochemical components of the adductor muscle, visceral mass, foot muscle and mantle were studied by biochemical analysis, from January to December, 2005. The reproductive cycle of this species can be classified into five successive stages: early active stage (December to January), late active stage (January to March), ripe stage (March to July), partially spawned stage (June to July) and spent/inactive stage (July to December). Total protein content was the highest in the foot muscle, the content was high in January (early active stage), the lowest in April (ripe stage), and was the highest in August (partially spawned stage). In the visceral mass, total protein content began to increase in February (late active stage) and reached a maximum in March (ripe stage). Thereafter, it gradually decreased between June and July (partially spawned stage). There was a strong negative correlation in total protein contents between visceral mass and mantle (r = -0.594, p = 0.042). Meanwhile there was a positive correlation between the adductor muscle and foot muscle, the correlation was not statistically significant (r = 0.507, p = 0.093). Total lipid content was the highest in the visceral mass; it was more than 2 to 5-fold higher than that in the adductor muscle, foot muscle, and mantle. Monthly changes in total lipid content were also most dynamic in the visceral mass. It was relatively higher between January and February, showed a maximum in March (the ripe stage), decreased rapidly from April to July (ripe and partially spawned stage), and gradually decreased from September to December (spent/inactive stage). There was a strong positive correlation in total lipid content between foot muscle and adductor muscle (r = 0.639, p = 0.025). Tthough a negative correlation was found between visceral mass and mantle (r = -0.392), the correlation was not statistically significant (p = 0.208). Glycogen contents changed within relatively narrow range and were similar among different tissues. There was no statistically significant correlation in glycogen contents among tissues.

• Clinical and Experimental Reproductive Medicine
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• v.28 no.3
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• pp.183-190
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• 2001

Objective: Recently, microdissection of tissue sections has been used increasingly for the isolation of morphologically identified homogeneous cell populations, thus overcoming the obstacle of tissue complexity for the analysis cell-specific expression of macromolecules. The aim of the present study was to establish the minimal conditions required for the RNA extraction and amplification from the cells captured by the laser captured microdissection. Methods : Mouse ovaries were fixed and cut into serial sections (7 im thickness). Oocytes were captured by laser captured microdissection (LCM) method by using PixCell $II^{TM}$ system. The frozen sections were fixed in 70% ethanol and stained with hematoxylin and eosin, while the paraffin sections were stained with Multiple stain. Sections were dehydrated in graded alcohols followed by xylene and air-dried for 20 min prior to LCM. All reactions were performed in ribonuclease free solutions to prevent RNA degradation. After LCM, total RNA extraction from the captured oocytes was performed using the guanidinium isothiocyanate (GITC) solution, and subsequently evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR) for glyceraldehyde-3-phosphate-dehydrogenase (GAPDH). Results: With the frozen sections, detection of the GAPDH mRNA expression in the number of captured 25 oocytes were not repeatable, but the expression was always detectable from 50 oocytes. With 25 oocytes, at least 27 PCR cycles were required, whereas with 50 oocytes, 21 cycles were enough to detect GA PDH expression. Amount of the primary cDNA required for RT-PCR was reduced down to at least 0.25 $\grave{i}$ l with 50 oocytes, thus the resting 19.75 il cDNA can be used for the testing other interested gene expression. Tissue-to-slide, tissue-to-tissue forces were very high in the paraffin sections, thus the greater number of cell procurement was required than the frozen sections. Conclusion: We have described a method for analyzing gene expression at the RNA level with the homogeneously microdissected cells from the small amount of tissues with complexity. We found that LCM coupled with RT-PCR could detect housekeeping gene expression in 50 oocytes captured. This technique can be easily applied for the study of gene expression with the small amount of tissues.

• The Journal of Korean Obstetrics and Gynecology
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• v.19 no.3
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• pp.55-68
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• 2006

Purpose : This study was undertaken to evaluate the effects of the different administration duration of Epimedium Herb extract solution on the spermatogenic abilities such as concentration, motility and morphological normality of sperm from the testis and the activities of sperm hyaluronidase. Methods : We used the 2-month-old mice and administered the extract solution of Epimedium Herb 0.3 ml/g/day for 30, 60, 90 and 120 days. The control group was administered the normal saline as the same way. We examined the number of total, motile and normal sperm from the cauda epididymis, the activities of sperm hyaluronidase. Also we observed changes of isolated testis before and after administration of Epimedium Herb extract solutions in the mice. And we compared the testicular tissue especially seminiferous tubules with the control and treated group by histochemical methods. Results : The significant differences were observed in the concentration of total sperm and normality of spermatozoa of the Epimedium Herb extract solution administered groups compared to the control group in 60, 90 and 120 days groups. The significant differences were observed the motility of the Epimedium Herb extract solution administered groups compared to the control group in 60 days group. In the histological analysis of the testicular tissues, the enlargement of testicular lobe diameter and apparent vasculogenesis between testicular lobes were observed in the Epimedium Herb extract solution administered groups compared to the control group, respectively. And the activity of hyaluronidase was significantly increased in the Epimedium Herb extract solution administered groups compared to the control group. Conclusion : This study shows that Epimedium Herb has the beneficial effect on the concentration, morphology and motility of sperm, the testicular tissues and the activities of sperm hyaluronidse in 60 days administration group. We can suggest that Epimedium Herb extract solution be useful for the treatment of male sexual dysfunction and infertility.

• Korean journal of applied entomology
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• v.43 no.3 s.136
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• pp.225-231
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• 2004

An endoparasitoid wasp, Cotesia plutellae, has been used for a biological control agent against the diamondback moth, Plutellae xylostella. It has a symbiotic polydnavirus in their reproductive tract, which is required for its successful parasitization. Here, we measured a specific replication time of the polydnavirus during female development of C. plutellae. We, also, analyzed the reproductive potentials of female C. plutellae under mating or different host conditions. At $25^{\circ}C$, pupal C. plutellae began to develop adult tissues such as compound eyes and wings since day 2. At day 5, all adult tissues including antennae were developed and were ready to emerge. With polyclonal antibody raised against C. plutellae polydnavirus, an immunobloting could confirm virus replication at day 4 during pupal stage. Virus particles could be visualized by transmission electron microscope in the oviduct lumen of day 5 pupae. After adult eclosion, venom gland and ovarian calyx increased in size, though ovarioles did not. Mated females layed large number of eggs (over $60\%$) at first 4 days during their mean longevity of ca. 8 days at $25^{\circ}C$. Unmated females showed less active ovipositional behavior, where all the eggs developed into males. C. Plutellae parasitized both P. xylostella and fall webworm, Hyphantria cunea. However, C. Plutellae developed faster and showed higher successful paarasitization in P. xylostella than in H. cunea.

• Clinical and Experimental Reproductive Medicine
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• v.27 no.3
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• pp.245-251
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• 2000

Objective: To investigate the distribution of BCL-2, BAX proteins and DNA fragmented cells in the normal human endometrium during at each menstrual cycle in order to find out whether apoptosis regulates cyclic endometrial change. Methods: Normal endometrial tissues were obtained from 40 patients, $32{\sim}45$ year of age, all with regular menstrual cycle, who were undergoing abdominal hysterectomy for myoma of uterus or cervical intraepithelial neoplasia for the period from 1992 through 1997. Immunohistochemical staining was used to determine the expression of BCL-2 and BAX protein with paraffin-embedded tissues. Results: BCL-2 was expressed on the glandular epithelial cells and stromal cells during the proliferative phase. The intensity of BCL-2 was increased predominantly on the basal layer than the functional layer in late proliferative phase. However, BCL-2 immunoreactivity was decreased in the secretory phase. BAX was expressed predominantly during the secretory phase. The intesity was increased in late secretory phase rather than early secretory phase. DNA fragmented cells were detected in a few cells at each phase. However, it was increased during the late secretory phase. Conclusion: Apoptosis-related genes, BCL-2 and BAX, may play a role in the regulation of cyclic endometrial change.

• Development and Reproduction
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• v.17 no.4
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• pp.461-467
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• 2013

Nesfatin-1/NUCB2, which is associated with the control of appetite and energy metabolism, was reported for the first time to be expressed in the hypothalamus. However, recent studies have shown that nesfatin-1/NUCB2 was expressed not only in the hypothalamus, but also in various tissues including digestive and reproductive organs. We also demonstrated that nesfatin-1/NUCB2 was expressed in the reproductive organs, pituitary gland, heart, lung, and gastrointestinal tract of the adult mouse. However, little is known about nesfatin-1/NUCB2 expression in fetal and neonatal mice. Therefore, we examined here the distribution of nesfatin-1/NUCB2 in various organs of fetal and neonatal mice and compared them with the distribution in adult mice. As a result of immunohistochemical staining, nesfatin-1/NUCB2 protein was expressed relatively higher in the lung, kidney, heart, and liver compared to other organs in the fetus. Western blot results also showed that nesfatin-1/NUCB2 protein was detected in the lung, kidney, heart, and stomach. Next, we compared the expression levels of nesfatin-1/NUCB2 mRNA in the fetus and neonate with the expression levels in both male and female adult mice. The expression levels in heart, lung, stomach, and kidney were higher compared with other organs in fetal and neonatal mice and in both male and female adult mice. Interestingly, the expression of nesfatin-1/NUCB2 mRNA in the kidney was dramatically increased in male and female adult mice compared to fetal and neonatal mice. These results indicate that nesfatin-1/NUCB2 may regulate the development and physiological function of mouse organs. In the future, we need more study on the function of nesfatin-1/NUCB2, which is highly expressed in the heart, lung, and kidney during mouse development.