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Biomedical subjects

I Kim

Publications and source records attributed to I Kim.

At least 163 records · Page 9Linked to original sources

Steroidogenic effects of lipoproteins and 25-hydroxycholesterol on luteal and ovarian cells: a comparison of two pseudopregnant rat models.

Steroidogenesis was compared between luteal cells from immature pseudopregnant (PSP) rats induced by either 5 IU pregnant mare serum gonadotropin (PMSG) alone or 50 IU PMSG combined with 25 IU human chorionic gonadotropin (hCG). It was also determined whether differences in steroidogenesis existed when the entire ovary (ovarian cells) or just luteal cells from Day 4 PSP rats were exposed in vitro to lipoproteins or 25-hydroxycholesterol (25-OH chol). In the absence of luteinizing hormone (LH), basal steroid accumulation, especially progesterone (P4) was around fourfold greater in luteal cells from rats treated with PMSG alone than from rats receiving PMSG-hCG. However, serum P4 and LH were about fivefold greater in the latter group. It is therefore likely that net cellular cholesterol uptake per luteal cell is lower in the PMSG-hCG treated rats, but this is offset by a much greater mass and number of corpora lutea. Lipoproteins (HDL and LDL) and 25-OH chol stimulated in vitro luteal steroidogenesis from rats treated with PMSG alone or PMSG-hCG, and their responses were virtually identical. Therefore, luteal steroidogenesis in the rat always depends on exogenous cholesterol even though treatment in the preovulatory period with PMS or PMSG-hCG and serum LH and follicle-stimulating hormone (FSH) levels on Day 4 PSP are very different. When ovarian cells from PMSG-hCG treated rats were incubated with LH plus HDL or 25-OHP, the production of 20 alpha-DHP was considerably greater than luteal cell production which may be due to a contribution from nonluteal cells. Indeed, about 30% of the cells in the PMSG-hCG group represent nonluteal components as estimated by weight and deoxyribonucleic acid content.

20-alpha-Dihydroprogesterone↗

Evidence for rapid loss of spare hCG receptors in the corpora lutea of the hypophysectomized rat.

In pregnant mare serum gonadotropin treated immature rats hypophysectomized on the day of ovulation (day 1) the corpora lutea (CL) persist as normal morphological structures and produce steroids, especially 20 alpha-dihydroprogesterone (20 alpha-DHP), for at least 40 days (Taya and Greenwald, 1982), although there is a rapid decline in human chorionic gonadotropin (hCG) binding sites (Kim and Greenwald, 1984). In this study the number of occupied and non-occupied hCG receptors in CL from hypophysectomized rats decreased to 14% and 36%, respectively, compared to intact day 5 pseudopregnant animals, but the binding affinity was unchanged. Decreased concentration of occupied hCG receptors paralleled hormonal levels of serum luteinizing hormone (LH) which were measurable in only 9 out of 20 animals and were near the lower limits of the assay (40 pg/ml). Luteal progesterone (P4) production in response to LH was markedly decreased after hypophysectomy, but the maximal P4 response to LH and 20 alpha-DHP production in response to LH and 8-Br-cAMP were the same in hypophysectomized and intact animals. Although hCG receptor concentration in CL decreased significantly after hypophysectomy, LH-stimulated luteal production of cAMP was almost the same in both groups. These results indicate that LH spare receptors which are uncoupled from cAMP exist in the CL of the intact pseudopregnant rat and that after hypophysectomy they quickly disappear within 4 days.

20-alpha-Dihydroprogesterone↗

Iron deficiency anemia and educational achievement.

The present study investigates the effect of iron supplementation on measures of school performance among 78 iron-deficient anemic and 41 nonanemic children in an economically deprived rural area in Central Java, Indonesia. All the subjects were treated for ancylostomiasis before iron supplementation. They were randomly assigned to either an iron or placebo group. Hematological and behavioral measurements were obtained immediately before (T1) and after (T2) the iron and placebo treatments. Iron treatment for a 3-mo period resulted in substantive increases in mean Hgb, Hct, and transferrin saturation among the iron-deficient anemic children. Furthermore, changes in the iron status of iron-deficient anemic children were associated with significant changes in the school achievement test scores of iron-deficient anemic children. T2 evaluation of achievement test scores indicated that the difference between iron-treated anemic and nonanemic children was still statistically significant. However, when T1 scores were entered as a covariate, iron-deficient anemic subjects treated with iron obtained significantly higher delta achievement scores. Findings from the present study indicate that iron supplementation among iron-deficient anemic children benefits learning processes as measured by the school achievement test scores.

Ancylostomiasis↗

Leydig cell tumors of the testis. A clinicopathological analysis of 40 cases and review of the literature.

The clinical and pathological features of 40 Leydig cell tumors of the testis were analyzed. The patients ranged from 2 to 90 (average 46.5) years of age. The most common initial manifestation was testicular swelling, which was sometimes associated with gynecomastia; 15% of the patients presented because of gynecomastia and were found to have palpable testicular tumors. All three children were brought to the physician because of isosexual pseudoprecocity. The tumors, one of which was asynchronously bilateral, ranged from 0.5 to 10.0 (average 3) cm in greatest diameter. They were usually well circumscribed, but in seven of them the margin with the adjacent testis was ill-defined. On microscopic examination the most common pattern was that of diffuse sheets of neoplastic cells, but insular, trabecular, pseudotubular, and ribbon-like patterns were also encountered. The neoplastic cells were most often large and polygonal with abundant eosinophilic, slightly granular cytoplasm; occasionally the cytoplasm was abundantly vacuolated. In eight tumors some of the cells were spindle-shaped, and in six some had scanty cytoplasm. Crystalloids of Reinke were identified in 35% of the tumors. Conspicuous nuclear atypicality was present in 12 tumors and the mitotic rate ranged from less than 1 to 32/10 high-power fields. Blood vessel invasion, lymphatic invasion, or both were identified in four tumors. Follow-up of 2 months to 22 years (average 4 years) was available for 30 patients. Five of them died as a result of spread of their tumor. A comparison of the clinically malignant tumors with those associated with survival for 2 or more years postoperatively revealed that the former occurred in older patients and were accompanied by symptoms of shorter duration and an absence of endocrine manifestations. The malignant tumors were larger, often had an infiltrative margin and had spread beyond the testis, frequently exhibited blood vessel or lymphatic invasion, and had a greater degree of cellular atypia and necrosis and a higher mitotic rate than the benign tumors.

Adult↗

Further studies on in vitro steroidogenesis by luteal cells from long-term hypophysectomized rats.

Immature pregnant mare's serum gonadotropin-treated rats were hypophysectomized on the day of ovulation (Day 1 of luteal function), and luteal steroidogenesis and human chorionic gonadotropin (hCG) and prolactin (Prl) binding sites were determined on Days 5, 10, 20 and 30 (H5- H30 ) compared with intact rats on Days 5 or 10 (C5 or C10). On H5, dispersed luteal cells secreted large amounts of progesterone (P), 20 alpha-dihydroprogesterone (20 alpha-DHP), 17 alpha-hydroxyprogesterone (17 alpha-OHP), and small amounts of testosterone (T) and estradiol-17 beta (E2), but between H10 and H30 , reduced levels of all steroids were produced except for 20 alpha-DHP. Addition of large amount of pregnenolone (P5) or P (100-1000 ng) to dispersed luteal cells increased production of P and 20 alpha-DHP in C5 and H5 rats. The higher serum levels and basal in vitro production of 20 alpha-DHP from H5 to H30 indicates that 20 alpha-oxidoreductase persists in the corpora lutea (CL) at high levels and that 3 beta-ol-dehydrogenase is also present but with P rapidly shunted into its principal metabolite. From H5 to H30 , addition of 10 ng P to luteal cells increased the production of 17 alpha-OHP and addition of 10 ng androstenedione (A) or T enhanced production of T and E2, indicating that 17 alpha-oxidoreductase, 17 beta-hydroxysteroid dehydrogenase and aromatase also persist in the CL. In vitro addition of 10 ng LH significantly stimulated production of P from luteal cells on C5 and H5, whereas on C10 and H10, 100 ng LH was required and on H20 and H30 , 1 microgram LH produced a minimal increase in P.(ABSTRACT TRUNCATED AT 250 WORDS)

17-alpha-Hydroxyprogesterone↗

Hormonal requirements for maintenance of follicular and luteal function in the hypophysectomized cyclic hamster.

The amounts of luteinizing hormone (LH), follicle-stimulating hormone (FSH) and prolactin (Prl) required for follicular development or luteal maintenance were established by hypophysectomizing hamsters between 0900-1100 h of Day 1 of the cycle (=morning of ovulation) and injecting the animals s.c. over the next 4 days to stimulate the normal cycle. Animals were killed at 1300 h on Day 4 or injected with human chorionic gonadotropin (hCG) at 1500 h on Day 4 and killed the next morning to determine the ovulation rate. Daily injection of 20 IU hCG resulted in 8 antral follicles per ovary and ovulation of 12.4 ova, but 20 micrograms LH (in saline) failed to develop any antral follicles; 20 micrograms LH in polyvinylpyrrolidone (PVP) - which prolongs its biological activity - matured 2-4 antral follicles per ovary and the animals ovulated 3 ova in response to hCG. However, injection of 5 micrograms FSH on Day 1 plus 20 micrograms LH (in PVP) on Days 1-4 produced normal numbers of antral follicles and ovulation of 15 ova. When 5 micrograms FSH was injected daily along with LH (in PVP), follicular development was accentuated and the animals ovulated 49 ova. Keeping FSH constant at 5 micrograms/day and reducing LH from 20 micrograms to 10 or 5 micrograms per day did not reduce the number of follicles maturing or ovulating. Daily injection of Prl did not affect follicular development but maintained corpora lutea (CL) in some animals. Combined injection of Prl and LH (in PVP), but not FSH, maintained active CL in all animals. Thus, the hypophysectomized hamster requires tonically high levels of LH for the hormone to exert its follicular and luteal effects with FSH and Prl, respectively.

Animals↗

Application of receiver-operator analysis to diagnostic tests of iron deficiency in man.

The objective of the present report is to demonstrate the use of receiver-operator characteristics (ROC) analysis in the selection of diagnostic tests for iron deficiency in a specific population. Conventional ROC curves were prepared with true positive fraction (TPF) and false positive fraction (FPF) determined by the application of different cut-off points for four indicators of iron status. ROC plots were then transformed into normal deviate scales. The advantages of Gaussian transformation of TPF and FPF when underlying decision functions are normally distributed are: the ROC curve is a straight line; and the separation between the two distributions and shape of these distributions can be simply quantitated as intercepts and slopes. In the present study, pretreatment hemoglobin concentration was the most robust diagnostic indicator of iron deficiency as operationally defined by a response of hemoglobin to iron treatment. Free erythrocyte protoporphyrin was a more sensitive and specific predictor than either serum ferritin or transferin saturation when a stringent operational definition of iron deficiency was used. These findings illustrate the utility of ROC analysis in discriminating between diagnostic indicators having different degrees of accuracy.

Anemia, Hypochromic↗

A species difference between hamster and rat in the effect of oestrogens on growth of large preantral follicles.

Intact or hypophysectomized 23-day-old hamsters and rats were injected s.c. with 2 mg diethylstilboestrol (DES) or 1 mg oestradiol cyclopentylpropionate (OECP) on Days 23-25 and killed on Day 26. Although serum oestradiol was elevated to the same high levels by OECP, ovarian and uterine weights were increased in the rat by OECP or DES whereas only the uterus responded in the hamster. This correlated with the ability of the oestrogens to increase significantly the number of large preantral and antral follicles in the intact rat but only the number of follicles with 2-3 layers of granulosa cells in the immature hamster. Qualitative study revealed that DES and OECP increased the number of large preantral follicles in the adult hypophysectomized rat but were ineffective in the adult hamster. It is concluded that for the immature and adult hamster oestrogens do not play a major role in the recruitment of large preantral follicles.

Animals↗

Effect of prostaglandin F2 alpha on Na+-K+-ATPase activity in luteal membranes.

Slices of rat corpora lutea (CL) incubated with prostaglandin F2 alpha (PGF2 alpha) in Krebs-Hensenleit (K-H) Ringer solution showed a decrease in Na+-K+-ATPase activity after 60 min of incubation. However, PGF2 alpha in vitro did not alter Na+-K+-ATPase activity of isolated luteal membrane fractions. Following PGF2 alpha-induced in vivo luteal regression, reduction of Vmax and elevation of the activation energy above transition temperature of the lipid phase of the membrane occurred without changes in Km, optimum pH and transition temperature. These results suggest that reduction of Na+-K+-ATPase activity after PGF2 alpha treatment may be due to reduction in the number of enzyme molecules or to masking of the active site of the enzyme without any change in enzyme characteristics. In addition, a change in membrane-bound enzyme activity may be an early step in PGF2 alpha-induced luteolysis.

Animals↗

Anterior interbody fusion in fractures and fracture-dislocations of the spine.

Twenty-five cases of unstable fractures and fracture-dislocations of the spine are reviewed. They were treated at the Catholic Medical College and Centre in a 3-year period, 1975 to 1978. 1. Eleven of the 25 patients were treated by anterior interbody fusion performed at 6 to 8 weeks from injury or initial surgery. 2. Eleven patients had neurological deficits, 3 with incomplete lesions and 8 with complete lesions. Open reduction and decompression laminectomies were performed on patients having neurological deficits prior to anterior interbody fusion. Two patients with incomplete paraplegia showed marked neurological recovery whilst one with complete paraplegia regained some sensation. 3. Solid clinical fusion was obtained in all but one patient within four months of interbody fusion. 4. Amongst the 18 patients with kyphosis at the time of admission 10 had a final improvement of their kyphosis ranging from 3 to 10 degrees (average 6 degrees). Three had no change and 5 demonstrated a mild increase of kyphosis (average 4 degrees). 5. Pain was relieved in 21 patients out of 25. The advantages of this technique include effective stabilization, prevention of late deformity and relatively early mobilization without internal fixation.

Adolescent↗

[Thrombectomy of the middle cerebral artery (author's transl)].

The case reports on the thrombo-embolectomy in the middle cerebral artery have been presented in a little frequency since 1954 when it was reported by Welch. But those in the acute stage have been reported very little. The present case concerns a male of 55 years old, who begun with the partial paralysis of the left upper limb and at the time of his entering the hospital, 24 hours later from onset, he showed the complete paralysis of the left upper limb and partial paralysis of the lower limb. His consciousness was in a mild confusional state. By the cerebral angiography, we could recognize the findings of obstruction in the right middle cerebral artery (the origin of angular artery), and see the retrograde filling from the right anterior cerebral artery. CT showed normal findings. Thrombectomy of the right middle cerebral artery was performed 30 hours later from the appearance of upper limb palsy (about 6 hours later from the onset of left hemiparesis). A fresh thrombus was easily extracted from the angular and central sulcus arteries. There occurred no serious complications after operation and then the improvement of the paralysis was recognized. This case was reported to be of help to judge the indication of such operation in an acute period and its effectiveness.

Cerebral Arteries↗

[On the phenomena of multiple extravasations of contrast medium in cerebral angiogram of the cases of hypertensive intracerebral hematoma (author's transl)].

It is interesting to note the pathological findings that the rupture of multiple microaneurysms in the basal ganglia appears to be the cause of the hypertensive intracerebral hematoma. But there is few report that the carotid angiogram demonstrated multiple leakages of contrast medium of intracerebral hematoma in vivo than in Westberg's postmortem angiogram. The authors experienced 15 cases of hypertensive intracerebral hematoma whose cerebral angiogram showed extravasation of contrast material. It was fifty-seven per cent of which angiogram within 6 hours after the stroke showed leakage of contrast medium. However, there was remarkably decreased appearance of the extravasation after 9 hours after the stroke. Moreover, emphasis showed be placed upon the facts that eleven cases of 15 cases showed more than two adjacent spotty extravasations of contrast medium and that six cases demonstrated the simultaneous multiple leakages of contrast material from more than two lentriculostriate arteries. These angiographic findings has led us to the conclusion that there is intimate correlation between the large hematoma and multiple ruptures of the microaneurysms of lentriculostriate arteries.

Adult↗