Reduced level of octamer binding transcription factor (Oct-1) is correlated with H2B histone gene repression during differentiation of HL-60 cells by all-trans retinoic acid

To gain insight on the role of transacting factors in the regulatory mechanism of H2B histone gene expression during the differentiation of HL-60 cells by all-trans retinoic acid (retinoic acid), the binding pattern of the nuclear proteins to various elements in the human H2B histone upstream region has been investigated with DNase I footprinting and DNA mobility shift assay. The level of H2B histone mRNA was markedly reduced at 48 hr in retinoic acid-treated HL-60 cells. The H2B histone mRNA was repressed in proportion to the concentration of retinoic acid. In DNase I footprinting analysis, a nuclear factor (octamer binding transcription factor, Oct-1) bound at -42 bp (ATTTGCAT) both before and after retinoic-acid-induced differentiation of HL-60 cells. One DNA-protein complex was formed by DNA mobility shift assay, and the level of Oct-1 decreased during retinoic-acid-induced differentiation. In the cycloheximide-treated HL-60 cells, the level of Oct-1 also reduced. These results suggest that the transcriptional repression of H2B histone gene during retinoic-acid-induced differentiation in HL-60 cells may be mediated by reduced level of Oct-1.

Effect of cannabidiol pretreatment on the kinetics of tetrahydrocannabinol metabolites in mouse brain

Tetrahydrocannabinol (THC), a major constituent of marijuana, and several of its metabolites are psychoactive in humans. Cannabidiol (CBD), a nonpsychoactive cannabinoid, inhibits hepatic microsomal THC metabolism and also modulates subjective psychological responses to THC in humans. Treatment of mice with CBD markedly decreased the hepatic microsomal in vitro formation of the major THC metabolites, 6 alpha-OH-THC and 7-OH-THC and increased formation of the minor metabolite 6 beta-OH-THC. THC blood levels were modestly elevated after CBD pretreatment and THC administration, compared with untreated controls, and area under the curve (AUC) of THC increased 50% as a function of decreased clearance. CBD pretreatment modestly increased the Cmax, AUC, or t1/2 of the major THC metabolites in the blood, whereas those kinetic parameters for 6 beta-OH-THC were dramatically increased. Changes in brain concentrations and kinetic parameters of the major THC metabolites did not reflect the relatively modest changes found in blood levels after CBD pretreatment, but exhibited large increases in AUC (7- to 15-fold) and t1/2 (2- to 4-fold), as well as in tmax. Changes in brain concentrations and kinetic parameters for 6 beta-OH-THC reflected the marked changes observed in blood levels after CBD pretreatment. Thus, CBD pretreatment resulted in large increases in AUC and t1/2 of all THC metabolites in brain, with a modest increase in AUC of THC. These changes in THC metabolite brain pharmacokinetics may contribute to the modulation of psychological responses to THC observed after CBD treatment.

Clomipramine treatment of paraphilias in elderly demented patients

Sexually inappropriate conduct often accompanies the disinhibition associated with dementia and neuropsychologic deficits. Management of these behaviors is problematic and time consuming. We report two cases in which paraphilias responded to treatment with clomipramine. This effect was not due to the sexual side effects of the drug (e.g., decreased ability to sustain an erection or orgasm). Careful monitoring of the elderly patient is required during treatment with clomipramine, particularly with regard to orthostasis, the increased risk of falls, and worsened confusion secondary to the potential risks of anticholinergic delirium and toxicity.

1991 cancer incidence in Seoul, Korea: results of the Implementation Study of the Seoul Cancer Registry

This article presents the results of the Implementation Study of the Seoul Cancer Registry, which started in July, 1991 as a population based cancer registry in Seoul, Korea. The completeness and validity of the registered data were evaluated using Mortality/Incidence ratio (M/I ratio), Histologically Verified Cases (HV%), Primary Site Uncertain (PSU%), and Age Unknown (Age UNK%). Owing to the additional active surveillance, the completeness of the data turned out to be fairly acceptable, except for the aged over 75(Mortality/Incidence ratio was over 100%). Eventhough the Seoul cancer registry(SCR) has further way to go in the completeness especially among elderly persons, the validity of SCR data was also acceptable in terms of HV%, PSU%, and Age UNK%. However, PSU% and Age UNK% might need to be further reduced to be comparable with other well established cancer registries. The age standardized incidence rates(ASR) of all cancers between July 1, 1991 and June 30, 1992 were 232.4/100,000 in males and 147.9/100,000 in females. The top five major sites of cancers in Seoul were the stomach, liver, lung, colo-rectum, and bladder in order in males, and the uterine cervix, stomach, breast, colo-rectum, and liver in females. Those 5 cancer sites comprised 68.9% and 64.7% of the total cancer incidence in males and females, respectively.

Pharmacokinetics of theophylline: effects of hepatic fibrosis in rats induced bile duct ligation

This experiment was performed to evaluate the usefulness of an experimental fibrosis model by bile duct ligation as a pharmacokinetic model of a disease state. First, experimental liver fibrosis was produced by bile duct ligation. At 4 weeks postoperation, a fibrotic condition was characterized by measurement of the aminoterminal procollagen type III peptide (PIIINP) level in serum, total collagen content in liver and light microscopic histology. Four weeks after bile duct ligation there was an increase in total collagen content of the liver to 430% of the initial values, accompanied by an increase of serum-PIIINP (385%). Secondly, we examined the pharmacokinetics of theophylline in the fibrotic rat induced by bile duct ligation. An i.v. dose of 8 mg of theophylline per kg of body weight was administered, and the levels of theophylline in serum were assayed by high performance liquid chromatography. The area under the serum concentration-time curve of theophylline was increased significantly in fibrotic rats compared with that of the control, and the total clearance of drug in fibrotic rats was low, averaging 22.6 mg/kg/h vs. 36.1 and 60.9 ml/kg/h in the control and the normal rat, respectively. However, the value of distribution during the beta-phase was not significantly affected by experimental liver fibrosis.

Oxidized lipids in the diet are a source of oxidized lipid in chylomicrons of human serum

We examined whether oxidized lipids in the diet determine the levels of oxidized lipid in human postprandial serum chylomicrons. After we fed subjects control corn oil containing low quantities of oxidized lipid, the levels of conjugated dienes in the chylomicron fraction were low (9.67 +/- 0.92 nmol/mumol triglyceride), and no thiobarbituric acid-reactive substances (TBARS) could be detected. However, when subjects were fed a highly oxidized oil, the conjugated diene content in chylomicrons was increased 4.7-fold to 46 +/- 5.63 nmol/mumol triglyceride, with 0.140 +/- 0.03 nmol TBARS/mumol triglyceride. When subjects were fed medium-oxidized oil, the degree of oxidation of the chylomicron lipids was moderately increased (21.86 +/- 2.03 nmol conjugated dienes/mumol triglyceride). Additionally, we found that chylomicrons isolated after ingestion of oxidized oil were more susceptible to CuSO4 oxidation than chylomicrons isolated after ingestion of the control oil. The lag time for oxidation decreased from 4.30 +/- 0.40 to 3.24 +/- 0.51 hours (P < .05). These data demonstrate that in humans dietary oxidized lipids are absorbed by the small intestine, incorporated into chylomicrons, and appear in the bloodstream, where they contribute to the total body pool of oxidized lipid.

Testosterone regulation of proto-oncogene c-myc expression in primary Sertoli cell cultures from prepubertal rats

The expression of c-myc has been associated with cell proliferation through changes of nuclear function. To evaluate the possibility that the proto-oncogene c-myc plays a role in testosterone-dependent gene regulation, the effects of testosterone on the expression of c-myc have been investigated in primary Sertoli cell cultures. Testosterone increased c-myc mRNA levels, with maximal stimulation reached in 16 hours. The induction of c-myc mRNA was dependent on the concentration of testosterone. Testosterone-induced c-myc mRNA levels were also increased in cells after addition of cycloheximide but reduced by actinomycin-D pretreatment. Even in the absence of hormone in culture medium, c-myc mRNA was clearly detectable in Sertoli cells from 8-day-old rats but hardly detectable in cells from 14 and 28 days of age. Testosterone stimulated c-myc mRNA expression in the Sertoli cells from only 8-/and 14-day-old rats. These results suggest that testosterone induces c-myc mRNA levels in the primary Sertoli cells from prepubertal rats, and then transient expression of c-myc may be responsible for some of the regulatory roles of testosterone-dependent genes in the Sertoli cells. The biological significance of testosterone-dependent c-myc induction is not known.

Milankovitch Forcing of the Last Interglacial Sea Level

During the last interglacial, sea level was as high as present, 4000 to 6000 years before peak Northern Hemisphere insolation receipt 126,000 years ago. The sea-level results are shown to be consistent with climate models, which simulate a 3 degrees to 4 degrees C July temperature increase from 140,000 to 130,000 years ago in high latitudes, with all Northern Hemisphere land areas being warmer than present by 130,000 years ago. The early warming occurs because obliquity peaked earlier than precession and because precession values were greater than present before peak precessional forcing occurred. These results indicate that a fuller understanding of the Milankovitch-climate connection requires consideration of fields other than just insolation forcing at 65 degrees N.

The effect of cannabidiol on mouse hepatic microsomal cytochrome P450-dependent anandamide metabolism

Anandamide (arachidonylethanolamide) has been identified as a brain constituent that selectively binds to the cannabinoid receptor and possesses cannabimimetic activity. Cytochromes P450 catalyze the oxidation of arachidonic acid to several metabolites possessing very potent pharmacological activity. We examined whether P450 would also metabolize anandamide, and whether cannabidiol (a cannabinoid which inactivates several P450s) would affect this metabolism. Mouse hepatic P450s were found to metabolize anandamide to at least 10 different metabolites, four of which were characterized by mass spectrometry. Cannabidiol selectively inhibited the formation of two of these four anandamide metabolites. The significance of anandamide metabolism remains to be explored.

Comparative study of hepatitis C virus antibody between hemodialysis and continuous ambulatory peritoneal dialysis patients

We have done cross sectional and prospective studies to determine the prevalence and the clinical significance of antibodies to the hepatitis C virus (Anti-HCV) in 54 hemodialysis (HD) patients and 227 continuous ambulatory peritoneal dialysis (CAPD) patients. Fifteen patients (27.8%) were anti-HCV (+) among the HD group, and twelve patients (5.3%) were anti-HCV (+) among the CAPD group. In the HD group, the positivity of anti-HCV correlated with the duration of HD, but there was no significant correlation with the history of transfusion, the amount of transfusion and abnormal alanine aminotransferase (ALT). At the follow-up study in 164 cases (HD 50 cases, CAPD 114 cases) after 6 months, one of 14 anti-HCV (+) CAPD patients was converted to anti-HCV (-) and two of 35 anti-HCV (-) HD patients were converted to anti-HCV (+). In conclusion, the prevalence of anti-HCV was significantly higher in HD patients compared to CAPD patients, and the positivity for anti-HCV in HD patients correlated with the duration of HD. A regular follow-up of anti-HCV and isolation of anti-HCV (+) HD patients with a separate machine may be needed to prevent the transmission of the hepatitis C virus during hemodialysis.

Regenerating liver-specific transacting factors of H2B histone gene are newly synthesized during liver regeneration

We have investigated DNA synthesis and levels of H2B histone mRNA, and the binding pattern of nuclear proteins to various elements in the rat H2B histone gene upstream region with DNase I footprinting assay. Both DNA synthesis and H2B histone mRNA level were increased with maximal stimulation reached at 24 hrs and 36 hrs after partial hepatectomy, respectively. In DNase I footprinting analysis, the nuclear factors interacting with the three elements, TATA at -19 bp (site AR), site B at -29 bp, and CAAT at -69 bp (site C) were required during maximal increase of H2B histone mRNA level after partial hepatectomy. The DNase I protection pattern by nuclear extract of the cycloheximide-treated regenerating liver showed the same results with normal liver. These results suggest that transcriptional regulation of H2B histone gene during liver regeneration may be mediated by nuclear factors that are newly induced by partial hepatectomy.

The prevalence study on restriction fragment length polymorphism analysis for the detection of hemophilia A carrier

We have analyzed two (BclI and XbaI) intragenic restriction fragment length polymorphisms (RFLPs) and St14 (DXS52) variable number of tandem repeats (VNTR) by rapid PCR method in 97 unrelated normal subjects. The incidences for positive Bc1I and XbaI polymorphic sites in the Koreans were 81% and 72%, respectively, which were higher than other ethnic groups but similar to that reported in the Chinese or Japanese, giving the heterozygosity rate of 0.32 and 0.40, respectively. The amplified allele size was 880 bp with no other polymorphism in the analysis of St14 (DXS52) VNTR. This finding should be taken into account in the planning of a prenatal diagnosis program for ethnic Koreans.

Magnetic resonance imaging in the evaluation of the lumbar herniated intervertebral disc

Two hundred and eleven patients with lumbar disc herniation at 242 levels were divided into 5 groups by their appearances on magnetic resonance imaging (MRI), and the findings at operation were compared to assess the accuracy of the MRI classification. There were no negative explorations. There was 92% sensitivity, 91% specificity and 92% accuracy for MRI in distinguishing protruded discs from other forms of lumbar disc herniation. For sequestrated discs there was 92% sensitivity, 99% specificity and 97% accuracy. In the extruded subligamentous type there was 71% sensitivity, 82% specificity and 79% accuracy, and 52% sensitivity, 92% specificity and 81% accuracy in the extruded transligamentous type. The overall accuracy of MRI predicting the types of herniated lumbar intervertebral disc was 85%. High resolution MRI is sensitive in detecting disc disease and specific in characterizing various subgroups of disc herniation, especially those which are sequestrated.

Reconstruction of the anterior cruciate ligament with Achilles tendon autograft

The increasingly serious complications of artificial ligaments and allografts have brought them into disrepute. Recently, autografts have drawn more attention. A new type of autograft, the Achilles tendon autograft, has been developed and applied to anterior cruciate ligament reconstructions. This report describes the advantages of the Achilles tendon autograft used and presents the results of a prospective study of 21 patients with minimum 2 year follow up. Of the 21 cases, 16 patients (75%) had a rating of excellent; 2 (10%) good, 2 (10%) fair, and 1 (5%) poor. Preoperative knee scores of 56.7 were improved to 89.5 postoperatively. The authors removed less than half of the Achilles tendon with the calcaneal bone incorporated. Through magnetic resonance imaging we confirmed that the remaining Achilles tendon of the donor site regained its volume and strength within a year without significant complication. Achilles tendon autograft offers the advantages of length, elastic strain modulus, reproducibility in technique, and consistency of the result without significant complications.

The diagnostic value of triple head single photon emission computed tomography (3H-SPECT) in avascular necrosis of the femoral head

Bone scans, triple head single photon emission computed tomography (3H-SPECT) and MRI scans were compared for their ability to detect avascular necrosis of the femoral head (AVN). 3H-SPECT was undertaken 5 hours after injection of 20 mCi of Tc-99m MDP for 20 minutes using a 3 detector rotating gamma camera (TRIAD, Trionix) equipped with ultra-high resolution collimators. The bone scan and 3H-SPECT were diagnosed as positive for AVN when a photopenic defect in the femoral head could be identified. The final diagnosis of AVN was established in 32 patients in 52 hips by MRI and/or histological findings. Unilateral disease was present in 11 patients, while 21 had bilateral disease. Of 32 patients and 52 hips, the bone scan, 3H-SPECT and MRI detected 37, 46 and 52 positive hips respectively. The sensitivity of 3H-SPECT (88.5%) was higher than that of the bone scans (71.5%), and was also higher than that previously reported using a single head SPECT. In AVN, the 3H-SPECT image was much clearer, and permitted more accurate localization of lesions than was possible by a bone scan. Studies including patients with diseases other than AVN and correlation with other methods of imaging is needed to define the role of 3H-SPECT in the diagnosis of AVN more precisely.

Eosinophilic granulopoiesis in human fetal liver

Eosinophilic granulopoiesis was investigated in human fetal liver during intrauterine life from 5 to 34 weeks of gestation. Eosinophilic granulocytes were observable for the first time at 5 weeks in the hepatic laminae and were frequently found in the late embryonic period around the large vessels and in the mesenchyme adjacent to the liver. Eosinophilic granulopoiesis increased gradually in the hepatic laminae (P < 0.01) after 20 weeks of gestation and in the portal areas (P < 0.05) after 16 weeks of gestation. The proportions of each cellular differentiation stage were relatively constant during fetal life, but a greater number of mature eosinophils were observed in the portal areas. Eosinophilic granulopoiesis was evident in all the hepatic tissue components, but developed more actively in portal areas than in hepatic laminae during intrauterine life. Eosinophilic granulopoiesis preceded both erythropoiesis and megakaryopoiesis in the human embryonic liver. Although the latter two occurred mainly in the hepatic laminae, eosinophilic granulopoiesis developed more actively in the portal areas, where it exhibited increasing activity along with the development of the component cells.

Inhibition of protein phosphatases blocks myogenesis by first altering MyoD binding activity

To examine the role of protein phosphatases in skeletal muscle differentiation, C2C12 myoblasts were treated with okadaic acid, a potent in vitro inhibitor of protein phosphatases 1 and 2A which regulate various cellular events in intact cells. We now show that okadaic acid treatment of the mouse myoblast C2C12 cell line reversibly altered the morphology of the cells and blocked differentiation. At a molecular level, it extinguished expression of the myogenic determination genes, MyoD1 and myogenin, but induced the expression of an inhibitor of differentiation, Id. Analysis of the MyoD1 promoter showed that inhibition of MyoD1 expression by okadaic acid occurs at the transcriptional level. These changes occur 10-20 h after okadaic acid treatment. However, within 1 h of treatment the ability of muscle extracts to support a specific MyoD-dependent gel mobility shift using a MyoD DNA binding site is lost. These data suggest that protein phosphatases play an important role during myogenic differentiation.

Post-transcriptional regulation of the human transforming growth factor-beta 1 gene

Since many lines of evidence suggest that expression of the transforming growth factor-beta 1 (TGF-beta 1) gene may be regulated post-transcriptionally, we examined the effect of the 5'-untranslated region (UTR) of this gene on TGF-beta 1 expression. For this purpose, fragments of the 840-nucleotide highly GC-rich TGF-beta 1 5'-UTR were inserted into the 5'-UTR of the structural gene for human growth hormone driven by the simian virus 40 early promoter. A portion of the 5'-UTR of TGF-beta 1 mRNA spanning the sequences from +11 to +147 was shown to inhibit growth hormone expression by as much as 22-fold. This effect was cell-specific; growth hormone production was inhibited in PC-3 human prostate adenocarcinoma and A-549 human lung adenocarcinoma cells, while no effect was seen in rat pheochromocytoma PC12 cells, which show efficient translation of endogenous TGF-beta 1 mRNA. Computer analysis showed that this region of the 5'-UTR contained a stable secondary stem-loop structure spanning sequences +49 to +76. This stem-loop region alone is sufficient to inhibit expression of the growth hormone gene, suggesting that it plays an important role in post-transcriptional regulation of TGF-beta 1 gene expression.