• Journal of Aquaculture
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• v.7 no.3
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• pp.159-164
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• 1994

All-female diploid Paralichtlrys olivaceus populations were produced by the artificial fertilization with the normal eggs and gynogenetic diploid males sperms. All-female triploids were also conducted to the fertilized eggs by cold shock. Floating, fertilization and hatching rates of the all-female diploid eggs were not significantly different from that of the diploid control eggs (P>0.05). All-female triploids were also not significantly different from their diploid controls or all-female diploid groups (P>0.05) in the floating and fertilization rates of eggs. However, hatching rates of all-female triploid groups were lower than that of the control (P<0.05). Induction of the triploids were confirmed by the measurement of erythrocyte sizes and by the chromosome counts. The volumes of erythrocytes and nucleus of triploid were larger than those of diploids, respectively. Percent incidences of triploid were $92.6\%$ in this experiment. The chromosome number of diploids and triploids showed 2n=48 and 3n=72, respectively, and their karyotypes were consisted of all acrocentric chromosomes. The gonads of 4-month-old triploids were histologically sterile.

• ALGAE
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• v.25 no.3
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• pp.105-113
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• 2010

A new red algal parasite, Symphyocolax koreana M. S. Kim, gen. et sp. nov., has been found on a specimen of Symphyocladia latiuscula (Harvey) Yamada, a member of the tribe Pterosiphonieae of the Rhodomelaceae; this genus has never before been reported to host red algal parasites. Here, the new parasite from Korea is described in terms of vegetative and reproductive morphology. The thallus has a minute, colored polysiphonous upright axis with many branches attached by pseudoparenchymatous pulvinate bases. There are six pericentral cells, with many corticated cells in the lower part of the main branches. Trichoblasts occur on dioecious male and female gametophytes, but not on tetrasporophytes. Procarps develop on suprabasal cells of trichoblasts and consist of a four-celled carpogonial branch and two sterile cells attached to the supporting cell. Spermatangial branches are borne one per each successive segment on monosiphonous pedicels in spiral positions with fertile trichoblast. Tetrasporangia are formed one per segment in a straight series and are tetrahedrally divided. Features of the vegetative axes, procarp, spermatangial trichoblasts, and tetrasporangial branching show that the new genus is an alloparasite belonging to the tribe Polysiphonieae.

• Journal of Veterinary Clinics
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• v.34 no.5
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• pp.377-380
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• 2017

An 8-year-old, shih-tzu female dog was referred due to neurological signs including paraparesis and back pain. On the complete blood count, hematologic analysis showed elevated leukocytosis. Serum biochemical analysis revealed elevated serum alkaline phosphatase concentration and C-reactive protein concentration. On the neurologic exam, the dog was suspected to have thoracolumbar myelopathy. On magnetic resonance imaging, there were masses within the spinal canal at L1-3 intervertebral disc space that were located dorsal to spinal cord. It was hyperintense on T1-, T2-weighted magnetic resonance images, Fluid-attenuated inversion recovery, and fat suppression images. The contrast-enhanced T1-weighted images showed no enhancement. The lesions were well circumscribed. The spinal cord was compressed and displaced ventrally by the mass. After removal of the masses via L1-L3 dorsal laminectomy, pyogranulomatous inflammation was confirmed by histopathological examination. Six months after surgery, the dog recovered uneventfully and remained fully ambulatory with no neurological deficits. This case demonstrates the utility of magnetic resonance imaging for the diagnosis of spinal canal pyogranulomatous inflammation.

• Reproductive and Developmental Biology
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• v.29 no.4
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• pp.269-271
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• 2005

The freemartinism is the most frequent form of intersexuality found in cattle, and females of heterosexual twins become sterile. With increase of twinning rates due to transfer of multiple embryos derived from in vitro fertilization, it is of great economic value to establish early diagnosis of freemartins to remove infertile individuals from breeding stock. In the present study polymerase chain reaction (PCR) of two different Y-chromosome specific segments (BRY.l and AMX/Y) was performed to identify freemartins from twins and less common single born freemartins in Korean Native Cattle (KNC). Two male-specific sequences were amplified in all heterosexual twins tested (n=5). In addition, Y-specific PCR products were detectable in one of the single born females (n=4) with visible genital abnormalities. These results suggest that the sensitivity of PCR-based assay may be sufficient to detect freemartinism in single born females as well as female partners of heterosexual twins in KNC.

• Journal of Plant Biology
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• v.39 no.1
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• pp.23-29
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• 1996

Morphology and reproduction of Polysiphonia atlantica Kapraun et J. Norris were studied on the basis of field and laboratory cultured materials collected from the coast of Korea. The plants consisted of prostrate and erect axes with an extremely soft flaccid texture. Axes were ecorticated and had four pericentral cells. The plants except for female gametophytes had few trichoblasts. Branches in the upper portion of the thallus grew to the same level, resulting in a flat-top form. Tetrasporangia were arranged in straight series. Spermatangial branches replaced whole trichoblasts and had a 1-2 celled serile tip. The procarp had a four celled carpogonial branch. After fertilization, the carpogonium contancted the surface of the supporting cell. The formation of the auxiliary cell from the supporting cell was somewhat delayed P. atlantica from Korea was similar to P. subtilissima Montagne in some features. However, the taxonomic differences between the two species were identified in the development of branches and the number of sterile cells at the tip of spermatangial branches.

• The Korean Journal of Zoology
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• v.13 no.4
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• pp.112-126
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• 1970

This paper deals with cytogenetical and cytochemical studies of the carp (Cyprinus carpio), the funa (Carassius carassius) and their hybrids. When kept under a confined condition, the carp and the funa mate andcan produce hybrids. Reciprocal crosses are also possible with similar results. The hybrids grow regularly with no observed abnormalities in the course of their development. They rank intermediate between the parent species in several characters. The hybrid males are completely sterile, while a hybrid female laid eggs in backcrossing. The spermatogenetic activity in hybrid testes is greatly disturbed. The chromosomes as observed in spermatogonial devision of hybrids are 100 in number, being the total sum of the haploid numbers of the parents, 50 for the carp and 50 for the funa. Meiosis in the hybrid testes is highly disturbed being arrested at early stages of the meiotic prophase. Most of the germ-cells undergo pycnotic degeneration during the period from late leptotene, and no spermatozoa are produced. In some hybrid specimens, the gonads show mosaic structures composed of testicular and ovarian elements, anevidence suggesting that sterility is associated with intersexuality caused by genetic unbalance between the parent species. The DNA amount in spermatogonial nuclei of thehybrids is approximately the same as that of liver nuclei, showing the 2n value. The DNA amount in the pachytene nuclei of the hybrids is less than the 4n value, while the parent species have the reduced amount of DNA in their pachytene nuclei. A consideration was made that the reduced amount of DNA in the hybrid cells may cause the disturbance of cellular activity leading to the subsequent degeneration of cells. Some aspects of enzymatic pattern in the carp, funa and their hybrids are. going on.

• Clinical and Experimental Reproductive Medicine
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• v.27 no.3
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• pp.301-305
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• 2000

Globozoospermia is a rare type of teratozoospermia. It occurs in 0.1% of all andrological patient's and used to be considered sterile. Globozoospermic patient has 100% round headed spermatozoa, but the spermiogram is normal. The spermatozoa show oval-shape head, the lack of a nuclear envelope, acrosome, and post acrosomal sheath. Objective: To report that a couple with infertility secondary to globozoospermia received ICSI treatment. Material and Method: Case report Results: In the first trial, fertilization was failed. In the second trial, 40% of oocytes were fertilized and all of these embryos were cleaved, but pregnancy did not achieved. In the third trial, sperm injected oocytes were exposed to 10 ${\mu}M$ calcium ionophore for 15 min. All of the injected oocytes were fertilized and proceeded to develop. Triplet pregnancy was achieved after the transfer of six embryos in their third cycle. One embryo vanished and the remaining twins (female) were delivered at 33 weeks of gestation by Caesarean section. Conclusion: This result shows that assisted activation following ICSI may overcome infertility associated with globozoospermia.

• Clinical and Experimental Pediatrics
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• v.58 no.5
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• pp.183-189
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• 2015

Purpose: Catheter urine (CATH-U) and suprapubic aspiration (SPA) are reliable urine collection methods for confirming urinary tract infections (UTI) in infants. However, noninvasive and easily accessible collecting bag urine (CBU) is widely used, despite its high contamination rate. This study investigated the validity of CBU cultures for diagnosing UTIs, using CATH-U culture results as the gold standard. Methods: We retrospectively analyzed 210 infants, 2- to 24-month-old, who presented to a tertiary care hospital's pediatrics department between September 2008 and August 2013. We reviewed the results of CBU and CATH-U cultures from the same infants. Results: CBU results, relative to CATH-U culture results (${\geq}10^4$ colony-forming units [CFU]/mL) were widely variable, ranging from no growth to ${\geq}10^5CFU/mL$. A CBU cutoff value of ${\geq}10^5CFU/mL$ resulted in false-positive and false-negative rates of 18% and 24%, respectively. The probability of a UTI increased when the CBU bacterial count was ${\geq}10^5/mL$ for all infants, both uncircumcised male infants and female infants (likelihood ratios [LRs], 4.16, 4.11, and 4.11, respectively). UTIs could not be excluded for female infants with a CBU bacterial density of $10^4-10^5$ (LR, 1.40). The LRs for predicting UTIs based on a positive dipstick test and a positive urinalysis were 4.19 and 3.11, respectively. Conclusion: The validity of obtaining urine sample from a sterile bag remains questionable. Inconclusive culture results from CBU should be confirmed with a more reliable method.

• Animal cells and systems
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• v.1 no.4
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• pp.595-602
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• 1997

Treatment of newborn female rats with gonadal steroids induces permanent sterility in adulthood. We investigated the alteration in expression patterns of gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) in neonatally estrogenized sterile rats (ESR). Newborn female rats received daily injections of 17${\beta}$-estradiol (E, 10 ${\mu}$g) from the day of birth (day 1) to postnatal day 5. Controls were subjected to vehicles over the same period. All animals were sacrificed on week 7 after birth. Hypothalamic GnRH mANA levels were markedly higher in all ESR than in controls, while hypothalamic GnRH contents in ESR increased in proportion to the frequency of daily administration of E. However, both pituitary LH6 mRNA and serum LH levels were inversely decreased by the same treatment. The data indicate that neonatal exposure of E equally elevates the expression of GnRH gene, but reduces the secretion of GnRH, accordingly leading to attenuation of LH6 gene expression and circulating LH levels. The temporal effect of E and/or progesterone (P) on GnRH and LH6 mRNA levels was also examined in ESR. Newborn female rats were daily injected with E (10 ${\mu}$g) or vehicle for five successive days from day 1 and ovariectomized at week 5. They were implanted with E (235 ${\mu}$g/ml) two days prior to week 7, injected with P (1 mg) 42 h later, and sacrificed 7 h after P administration. In ovariectomized controls, hypothalamic GnRH mRNA levels were dropped to half by treatment of E and restored by subsequent treatment of P. The negative feedback action of E on GnRH mRNA levels observed in ovariectomized rats was completely blocked by neonatal exposure of E. The change in pituitary LH mRNA levels was similar to that in hypothalamic GnRH mRNA levels. Taken together, the results suggest that neonatal treatment of E alters the synthesis and release of GnRH in adulthood and furthermore blocks the negative feedback regulation of E which occurs normally after ovariectomy.

• Parasites, Hosts and Diseases
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• v.36 no.2
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• pp.99-108
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• 1998

The present study was performed to check the viability of eggs, filariform larvae and adults of Strongvloines venezueLensis exposed to various conditions for an in vitro maintenance. The eggs in the feces remained viable for about 25 days at $4^{\circ}C$ and 15 days at room temperature. However, the isolated eggs in sterile saline lost their viability within 24 hr at $4^{\circ}C$. The eggs in morula stage were very sensitive to air drying and rapidly lost their viability (=12 hrs. Filariform larvae survived for a maximum period of 45 days in fecal suspension and 28 days in 0.12% nutrient broth in polyvinyl culture bags maintained at $20^{\circ}C$. On the other hand, those isolated from nutrient broth cultures survived for a maximum period of 32 days in tap water and 22 days in sterile saline at $20^{\circ}C$. The mature adult worms obtained from experimentally infected rats survived maximally for 9 days in serum supplemented (10% rat-serum) 0.12% nutrient broth and 4 days in serum free nutrient broth at $37^{\circ}C$ while the culture media were changed at an alternate day. The adult female worms deposited fertile eggs in serum supplemented and serum free nutrient broth cultures, however, the hatched larvae (Ll) were not able to develop to the filariform stage in the culture media and found to die within 24 hr of maintenance. The present findings on an in vitro maintenance of different stages of 5. uenezueLetis may provide useful information for biological and biochemical studies with Strongyloines species. Key words: Strongvloides venezuelensis. viability in vitro maintenance, free-living filariform larvae (L3), embryonation of eggs