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Biomedical subjects

M H Kim

Publications and source records attributed to M H Kim.

At least 271 records · Page 15Linked to original sources

The effect of prolactin on murine in vitro fertilization and embryo development.

Elevated levels of serum and follicular fluid prolactin occur in women undergoing ovulation induction with both clomiphene citrate and gonadotropin therapy. Prolactin's effect on oocyte fertilization and embryo cleavage has not been fully characterized. Using a murine model, we investigated the effect of prolactin on in vitro fertilization and subsequent embryo cleavage in media containing 150, 400, and 600 ng/ml purified mouse prolactin. No difference was found in fertilization rates when compared with control rates. Culture of both in vivo and in vitro fertilized two-cell embryos in murine prolactin at 150, 400, and 600 ng/ml showed no significant difference in blastocyst, morula, or embryo degeneration rates when compared with control rates. An assay for binding of murine prolactin to spermatozoa, oocytes, and the embryo at various cleavage stages revealed no specific murine prolactin binding. These in vitro experimental results fail to show a role for murine prolactin in effecting mature oocyte fertilization or subsequent embryo cleavage. The lack of binding of murine prolactin to the gametes and early developing embryo supports the in vitro findings.

Animals↗

Effect of a synthetic platelet activating factor on steroidogenesis of cultured porcine granulosa cells.

An embryo-derived platelet activating factor has been demonstrated to play an important role in reproduction. This report examined the effect of various doses of a synthetic platelet activating factor on the production of progesterone by porcine granulosa cells in culture. Granulosa cells aspirated from ovarian follicles of prepubertal gilts were grown for 24 hours in Dulbecco's Modified Eagles Media: Ham's F-12 with 5% fetal bovine serum and 1 micrograms/ml insulin. Cells were washed once in serum-free media and then cultured for an additional 48 hours with 0 to 5000 ng/ml of the platelet activating factor in media containing either 0.25% bovine serum albumin or 1% fetal bovine serum. Cells grown with fetal bovine serum produced 50% of the amount of progesterone that was produced in the absence of serum. Low doses of the platelet activating factor caused a slight decrease in progesterone production. Higher doses (greater than 500 ng/ml) in serum-free media caused a marked decrease in progesterone production. Serum had a protective effect at high doses of platelet activating factor which was probably mediated by enzymatic degradation of the platelet activating factor. In summary, platelet activating factor had no stimulatory effect on production of progesterone by porcine granulosa cells in culture.

Animals↗

Antisperm antibodies in women undergoing intrauterine insemination.

Intrauterine insemination is widely used for the treatment of infertility as a result of cervical or male factors or empirically before in vitro fertilization or gamete intrafallopian transfer. This study was designed to confirm or refute the theoretical concern that intrauterine insemination may induce antisperm antibodies in such women. Serum and cervical mucus were obtained at the first, fourth, and sixth intrauterine inseminations. The serum was screened by the Immunobead test for IgG and IgA. If screening results were positive (greater than 10% binding), antisperm antibodies were titered by the microimmobilization and microagglutination tests. The Immunobead test was performed on the cervical mucus after liquefication with bromelin. Ninety-three patients were followed up prospectively. Of these, 40 completed six intrauterine insemination cycles and the remaining 53 completed four cycles. Low transient antisperm antibody levels were detected in 10.8% of the patients and would not be expected to affect the prognosis for fertility. It is concluded that intrauterine insemination does not induce significant antisperm antibody production in women.

Antibodies↗

Feasibility of digital teleradiology for imaging evaluation of patients with acute right upper quadrant abdominal pain.

To assess the utility of a commercially available digital teleradiology system in evaluating patients with acute pain in the right upper quadrant, hard-copy images from 100 examinations (50 hepatobiliary scintigrams and 50 sonograms of the right upper quadrant) were digitized, transmitted via standard telephone lines, and viewed remotely on a video monitor. Video and hard-copy interpretations were then compared for degree of concordance. For the scintigraphic studies, hard-copy and video images were equal in demonstrating gallbladder and bile duct activity. Video images failed to depict the presence of bowel activity in one case. Gallstones were depicted equally well on hard-copy and video sonographic images. The video interpreters overestimated the presence of abnormal hepatic parenchyma and overlooked one case of right hydronephrosis. The video interpretations of the scintigrams and sonograms showed an overall error rate of 4%, comparable to the rate obtained when radiographs are interpreted remotely with digital teleradiology systems.

Abdominal Pain↗

Inhibin suppresses human chorionic gonadotropin secretion in term, but not first trimester, placenta.

Inhibin is produced by the placenta, with serum concentrations rising throughout pregnancy. In contrast, hCG serum concentrations peak in the first trimester and are 80-90% lower at term. This study was designed to determine the effect of inhibin on hCG secretion both early and late in gestation. Villus tissue from 3 term and 3 first trimester (8-10 week) placentas was maintained in an in vitro explant culture model for 5 days. Tissue from each placenta was incubated with control medium in 24 replicate wells for the first 72 h. During the final 48 h, 12 wells received control medium, and 12 wells received medium containing 1% rabbit antiserum raised against the alpha-subunit (residues 1-32) of the human inhibin peptide. The antiserum demonstrated biological activity by increasing serum FSH concentrations in an immature female rat bioassay. The relative increase in hCG secretion at the conclusion of days 4 and 5 in control and antiserum-treated groups for each first trimester and term placenta were compared to pretreatment hCG concentrations on day 3. The relative increases in hCG secretion of first trimester control groups on day 4 (mean +/- SD, 34 +/- 11%) and day 5 (63 +/- 23%) were compared to those in antiserum-treated groups on day 4 (39 +/- 13%) and day 5 (54 +/- 5%) and showed no significant difference between groups on either day. The same comparison in term cultures showed the relative increases in hCG secretion of control groups on day 4 (31 +/- 10%) and day 5 (64 +/- 50%) to be significantly lower than those in antiserum-treated groups on day 4 (100 +/- 41%) and day 5 (150 +/- 108%; P less than 0.001). These findings suggest that inhibin suppresses hCG secretion in term, but not first trimester, placentas.

Animals↗

Two cases of suspected arteriosclerotic optical chiasmal syndrome.

Optic chiasmal syndrome due to arteriosclerotic vascular changes is rate. To our knowledge, there has been no report of arteriosclerotic chiasmal syndrome in Korea. In our two cases, other causes of chiasmal syndrome were not detected by MRI, four-vessel cerebral angiography, CSF study, and special laboratory examinations including ANA test, RA factor, and LE cell. With conservative treatment, the visual fields of the two patients are showing progressive improvement. We report here two cases of suspected arteriosclerotic optic chiasmal syndrome.

Adult↗

Current trends in human IVF and other assisted reproductive technologies.

The new reproductive technologies such as IVF, GIFT, ZIFT, and micromanipulation have had a profound influence on the therapeutic and diagnostic management of infertility, and in turn have resulted in better understanding of human fertilization and embryo development. While the clinical pregnancy rates in GIFT and ZIFT procedures are comparable to the natural fecundity in the population at large, pregnancy rates in IVF have been generally lower. Further investigations should be directed to improve the implantation rates, and to develop better controlled methods of multiple follicle development. Although more studies are needed, a recent report of potential utilization of nonstimulated oocytes for donor programs as well as IVF-cryopreservation was a promising new development (Cha et al. 1989). Other exciting prospects on the horizon are the possibilities of gene transfer for the treatment of certain genetic diseases and diagnostic applications of embryonal biopsy. These new technologies have also generated serious ethical and legal issues. Any ethical or legal guidelines affecting new reproductive technologies should be developed to protect all participants only when the need for regulation is clear. Ethical guidelines and appropriate legislations with contributions from the medical and scientific community are gradually being established worldwide.

Cryopreservation↗

Three cases of congenital hepatic fibrosis with Caroli's disease in three siblings.

Congenital hepatic fibrosis is a relatively rare disease of children and young adults characterized by hard hepatomegaly, portal hypertension with relative preservation of liver function and underlying architecture, and frequent renal involvement. We experienced 3 cases of congenital hepatic fibrosis with Caroli's disease in 3 siblings, whose clinical manifestations were diverse, such as repeated cholangitis, variceal hemorrhage, or intrahepatic stones. All of them had multiple renal cysts, so we supposed that the clinical entities of these patients were in the spectrum of fibropolycystic disease of the liver and kidney.

Adult↗

Electric field mediated transfer of enzymes into human oocytes.

In an attempt to develop a simple, atraumatic technique of introducing macromolecules and enzymes into human oocytes, we have investigated the use of electric field mediated transfer. Eighty-seven percent of human oocytes showed cytochemical evidence for the transfer of the enzyme horseradish peroxidase (HRP). The cell viability after this procedure was 89% as determined by the vital dye rhodamine-123. This study demonstrates that the enzyme HRP can be transferred into human oocytes using the electric field mediated method. Functional activity of the enzyme was maintained after this transfer.

3,3'-Diaminobenzidine↗

Effects of progesterone and a progesterone antagonist (RU486) on germinal vesicle breakdown in the mouse.

The possibility that ovarian steroids may participate in the inhibition of meiosis has not been rigorously examined. Since progesterone levels are extremely high in follicular fluid prior to ovulation, we tested the possibility that this steroid may be involved in oocyte maturation. To this end, we collected follicular oocytes and cultured them in the presence of dibutyrl cAMP (Bt2), progesterone, and/or the progesterone antagonist RU486 and assessed maturation evidenced by germinal vesicle breakdown (GVBD). Denuded oocytes or cumulus masses collected in the presence of 1 mM Bt2 and subsequently cultured in 25 microM progesterone did not undergo GVBD. However, denuded oocytes and cumulus masses collected in the presence of progesterone and not Bt2 did undergo GVBD (93%). Concentrations of Bt2 (150 microM) that would not inhibit GVBD were inhibitory when used in the presence of progesterone (1-25 microM). Competition experiments using increasing concentrations of the progesterone antagonist RU486 (1-100 microM) did not block the ability of progesterone to enhance the activity of Bt2. We conclude that progesterone alone does not block GVBD; however, in the presence of low concentrations of cAMP it is extremely effective in blocking GVBD. The synergistic activity of progesterone does not appear to be mediated by the progesterone receptor. The data suggest that progesterone and cAMP may operate cooperatively to inhibit meiosis in the ovarian follicle.

Animals↗

A study on the recent trend and risk factors of cerebrovascular disease.

Six hundred eighty seven cases of cerebrovascular disease, confirmed by C-T scan, were evaluated at Hanyang University Hospital from January 1985, to December 1988, and the following results were obtained. 1) The incidence of cerebral infarction was markedly increased in the last 5 years. 2) Cerebral hemorrhage showed a peak age of incidence in the fifties, cerebral infarction in the sixties. 3) Among the preceding diseases at the onset of cerebrovascular disease, hypertension was the most common. 4) Total lipid, Total-cholesterol/HDL-cholesterol ratio were significantly higher in cerebral infarction than in cerebral hemorrhage. 5) Triglyceride concentration and total cholesterol concentration were also higher in cerebral infarction than those of cerebral hemorrhage, but statistically not significant. 6) In cerebral infarction HDL-cholesterol concentration was significantly lower than that of cerebral hemorrhage. (p less than 0.01.) 7) In cerebral infarction, hematocrit and hemoglobin concentration were significantly higher, respectively, than those of cerebral hemorrhage.

Adult↗

Fibrinolytic response to standardized venous occlusion in different age groups.

The purpose of this study was to find out the range and distribution of fibrinolytic response to standardized venous occlusion in healthy volunteers and to determine whether there were any differences according to age and sex. In 118 healthy volunteers (55 males, 63 females) of various age groups, the total fibrinolytic activity in euglobulin fractions was measured by a well controlled fibrin plate method before and after venous occlusion of 5 minutes at 100 mmHg. The difference between our method and previous methods is that we occluded for a relatively shorter duration than that of previous studies (15-20 minutes) at constant pressure (100 mmHg), instead of midway between systolic and diastolic pressure. This method was reliable and reproducible as a tool to qualify and assess the fibrinolytic activity capacity of individuals. The results showed that there was no difference in basal fibrinolytic activity and the response to stimuli in various age groups (p greater than 0.25) and in male and female groups (0.1 less than p less than 0.375).

Adolescent↗

Regulation of apolipoprotein E synthesis and mRNA by diet and hormones.

Rats were fasted or fasted and refed simple purified diets so the effects of individual carbohydrates or fats could be studied. Freshly isolated hepatocytes from these animals were used to measure both apoE synthesis and mRNA levels so any changes in apoE synthesis that might occur without changes in its mRNA could be detected. Some of these experiments were done with both sexes. Both fasting and fasting and refeeding a 60% glucose fat-free diet significantly increased spoE synthesis. However, cyclic AMP is not likely to rapidly mediate the effect of fasting since dibutyryl cAMP slightly lowered (rather than increased) apoE synthesis and mRNA when injected into rats for 4.5 h. Dietary fat had no effect either in the absence of carbohydrate or when consumption of carbohydrate was constant in pair-fed rats. ApoE mRNA levels remained normal for 4 days in primary hepatocytes cultured in medium that had only amino acids as an energy source. Added hormones or fructose had no significant effect. Thus, only fasting and fasting and refeeding glucose were able to significantly change apoE synthesis or mRNA levels. Synthesis of apoE may be regulated to increase when apoE is secreted with very low density lipoprotein or when apoE in secreted high density lipoprotein is needed to acquire cholesteryl esters for the synthesis of bile salts and acids by liver.

Animals↗

Atypical luteinizing hormone rise and associated fertilization failure in non-male factor in vitro fertilization patients.

The purpose of this investigation was to analyze fertilization failure in non-male factor infertility in vitro fertilization (IVF) patients. Twenty-five nonfertilized IVF patients were compared with 57 successfully fertilized IVF patients. Patients were matched for age, ovulation-induction protocol, and cycle. The two groups were similar with respect to infertility etiology, peak estradiol, and total oocytes retrieved at laparoscopy. There was a greater incidence of primary infertility (64 versus 49%) and mean years of infertility (5.4 +/- 0.4 versus 4.6 +/- 0.3) in the nonfertilization group, although these differences were not statistically significant. Most important, the nonfertilization patients had a greater incidence of an atypical LH rise prior to hCG administration (60 versus 18%; P less than .001) and fewer mature oocytes (2.0 +/- 0.3 verus 3.4 +/- 0.3; P less than .01). Stepwise linear regression analysis yielded four primary factors for predicting fertilization failure: infertility duration, primary infertility, number of mature oocytes, and presence of LH rise. These findings help characterize several potential factors other than oligozoospermia that are associated with nonfertilization, and support LH monitoring in IVF and gamete intrafallopian tube transport patients.

Adult↗

Search for the optimal sequence of the ribosome binding site by random oligonucleotide-directed mutagenesis.

Synthetic DNA duplexes corresponding to the ribosome binding site (RBS) were synthesized through the phosphite method on solid support. The synthetic RBS DNA with partial random sequences was inserted into an appropriate site between the lpp-lac promoter and the beta-galactosidase structural gene in plasmid pMKT2. The level of beta-galactosidase expression was correlated with the color intensity of the recombinant colonies on X-gal plates. The bluest colonies were isolated and characterized with respect to beta-galactosidase enzyme activity and RBS sequence. There was good correlation between color intensity and the level of the enzyme activity, and this provided a reliable phenotypic screening method in the search for the optimal regulatory sequences. Novel RBS sequences obtained here show not only the unique nucleotide distribution, but also strong complemetarity to the 3' end region of 16S rRNA, from which could be deduced a generalized RBS sequence, the position of the SD region, and the 16S rRNA position mediated during translation initiation.

Bacterial Proteins↗

Effects of relaxin on the fertilization capacity of human spermatozoa.

Relaxin, a polypeptide hormone found in human seminal plasma, exerted favorable effects on the function of spermatozoa. This study was designed to investigate the effect of this hormone on the fertilization capacity of human spermatozoa from 10 oligospermic men (group A), 11 asthenospermic men (group B), 10 normospermic infertile men (group C), and 10 men with verified fertility (group D). We compared the effects of purified porcine relaxin at different concentrations (0, 50, and 150 ng/ml). Parameters include motility, hypoosmolar swelling test, and zona-free hamster egg penetration test. In group A and group B, relaxin increased the results of the hamster egg penetration test and motility. In group C, results of the hamster egg penetration test and motility improved only at the concentration of 50 ng/ml. In group D, relaxin increased the results of the hamster egg penetration test only at a concentration of 150 ng/ml. Results of the hypoosmolar swelling test were not consistently altered in any study group. Relaxin appears to enhance the fertilization capacity and motility of human spermatozoa in oligospermic and asthenospermic subjects.

Animals↗

The effects of progesterone antagonist RU 486 on mouse oocyte maturation, ovulation, fertilization, and cleavage.

The antiprogesterone RU 486 was utilized to evaluate the possible role of progesterone in ovum maturation, ovulation, fertilization, and embryo cleavage. After gonadotropin treatment, CD-1 mice received the following experimental agents: group 1, an oil vehicle; group 2, 1 mg progesterone; group 3, 1 mg antiprogesterone (RU 486); group 4, 1 mg RU 486 and 1 mg dexamethasone. Each group of animals was injected simultaneously for 2 days (concomitant with human chorionic gonadotropin and the day after coitus). Ova or embryos were obtained on day 1, 2, 3, or 4 after human chorionic gonadotropin by flushing uteri and tubes. No differences were apparent in number of oocytes ovulated, ovum maturation, or number of oocytes progressing to two-cell embryos. However, on day 3 a marked reduction in embryos retrieved from the oviduct and uterus was apparent in the RU 486-treated groups (group 1, 84; group 3.0; group 4, 17) (p less than 0.001). In addition, few cleavage stage embryos were recovered on day 4 in the RU 486-treated groups (group 1, 74; group 2, 70; group 3, 2; group 4, 0) (p less than 0.0001). Freshly ovulated cumulus masses were recovered from the oviducts on day 4 in groups 3 and 4 (coincident with resumption of the estrous cycle). In conclusion, periovulatory RU 486 injections had no effect on nuclear maturation, ovulation, fertilization, or first cleavage division. Progesterone may not have an obligatory role in these processes. However, RU 486 administration did result in a reduced number of embryos retrieved on days 3 and 4 because of either early expulsion or destruction of the embryos.

Animals↗