Expression of transforming growth factor-alpha mRNA in livers of patients with chronic viral hepatitis and hepatocellular carcinoma

BACKGROUND

Transforming growth factor-alpha (TGFalpha) is an important autocrine growth factor of hepatocytes. The authors evaluated the roles of TGFalpha in chronic viral hepatitis (CVH) and hepatocellular carcinoma (HCC).

METHODS

The authors measured the amounts of TGFalpha mRNA in liver tissues from 18 patients with HCC, 31 patients with CVH, and 7 normal controls. " Hot-start" reverse transcription-polymerase chain reaction (RT-PCR) using oligo-dT and specific primers detected TGFalpha mRNA in total cellular RNA extracted from liver tissues. The levels of TGFalpha mRNA were determined by the end point titers of serial, two-fold dilutions of cDNA. The amounts of hepatitis B virus RNA (HBV-RNA) in livers of patients with chronic hepatitis B also were measured by Northern blot hybridization.

RESULTS

TGFalpha mRNA levels were extremely higher in patients with HCC compared with patients with CVH and normal controls, and the levels in patients with CVH also were elevated compared with normal controls. The levels of TGFalpha mRNA were overexpressed in the underlying livers of patients with HCC compared with patients with CVH, although they were lower than those found in HCC tissues. The levels of TGFalpha mRNA were higher in samples from patients with chronic hepatitis B than in samples from patients with chronic hepatitis C. The levels of TGFalpha mRNA were not correlated with serum alanine aminotransferase or HBV-RNA levels in liver tissues in patients with chronic hepatitis B. However, the expression of TGFalpha mRNA tended to be higher in the livers of patients with raised serum alpha-fetoprotein levels.

CONCLUSIONS

The overexpression of TGFalpha mRNA in the liver seems to be associated with the regeneration of hepatocytes rather than hepatic necrosis or viral replication. Also, it may be related closely to the development or progression of HCC, especially in the livers of patients with chronic hepatitis B.

A virtual instrument ergonomics workstation for measuring the mental workload of performing video-endoscopic surgery

The visual and physical interface imposed on the surgeon by video-endoscopic surgery (VES) increases the surgeon's mental workload. Ergonomic studies are needed to develop ways to reduce this workload. We used virtual instrumentation to devise a portable ergonomic workstation to compare the surgeon's mental workloads during simulated open surgery and VES. The system measures palmar tonic skin conductance level (SCL) and electrooculogram (EOG) and frontalis electrical activity to monitor mental stress and concentration levels. We used the system at a national surgery conference on volunteer subjects during a rest period and as they performed simulated surgery, consisting of typing knots using open and VES techniques. The subjects were asked to self-rate their levels of mental concentration and stress during these activities and reported that both progressively increased from rest to the open surgery task to the VES task. The subjects tied fewer knots during the VES than the open task, consistent with the increased demands of the VES task. The SCL progressively increased from rest to the open task to the VES task, correlating with the subjects' reported increase in mental stress level. Eye blinks and low frequency EOG activity decreased from rest to the open task, consistent with the subjects' reported increase in mental concentration level. From the open to the VES task, eye blinks and EOG activity increased, as expected given the greater demands of the VES task. High frequency frontalis activity merits further study as another indicator of the subjects' levels of mental concentration and stress.

A second photochromic bacteriophytochrome from Synechocystis sp. PCC 6803: spectral analysis and down-regulation by light

It now appears that photosynthetic prokaryotes and lower eukaryotes possess higher plant phytochrome-like proteins. In this work, a second phytochrome-like gene was isolated, in addition to the recently identified Cph1 phytochrome, from the Synechocystis sp. PCC 6803, and its gene product was characterized photochemically. The open reading frame sll0821 (designated cph2 in this work) has structural characteristics similar to those of the plant phytochromes and the Synechocystis Cph1 with high amino acid sequence homology in the N-terminal chromophore binding domain. The predicted Cph2 protein consists of 1276 amino acids with a calculated molecular mass of 145 kDa. Interestingly, the Cph2 protein has two putative chromophore binding domains, one around Cys-129 and the other around Cys-1022. The Cph2 was overexpressed in E. coli as an Intein/CBD (chitin binding domain) fusion and in vitro reconstituted with phycocyanobilin (PCB) or phytochromobilin (PPhiB). Both the Cph2-PCB and Cph2-PPhiB adducts showed the typical photochromic reversibility with the difference spectral maxima at 643/690 and 655/701 nm, respectively. The Cys-129 was confirmed to be the chromophore binding residue by in vitro mutagenesis and Zn(2+) fluorescence. The microenvironment of the chromophore in Cph2 seems to be similar to that in plant phytochromes. The cph2 gene expression was dark-induced and down-regulated to a basal level by light, like the cph1 gene. These observations suggest that Synechocystis species have multiple photosensory proteins, probably with distinct roles, as in higher plants.

Expression of transforming growth factor-alpha mRNA in livers of patients with chronic viral hepatitis and hepatocellular carcinoma

BACKGROUND

Transforming growth factor-alpha (TGFalpha) is an important autocrine growth factor of hepatocytes. The authors evaluated the roles of TGFalpha in chronic viral hepatitis (CVH) and hepatocellular carcinoma (HCC).

METHODS

The authors measured the amounts of TGFalpha mRNA in liver tissues from 18 patients with HCC, 31 patients with CVH, and 7 normal controls. " Hot-start" reverse transcription-polymerase chain reaction (RT-PCR) using oligo-dT and specific primers detected TGFalpha mRNA in total cellular RNA extracted from liver tissues. The levels of TGFalpha mRNA were determined by the end point titers of serial, two-fold dilutions of cDNA. The amounts of hepatitis B virus RNA (HBV-RNA) in livers of patients with chronic hepatitis B also were measured by Northern blot hybridization.

RESULTS

TGFalpha mRNA levels were extremely higher in patients with HCC compared with patients with CVH and normal controls, and the levels in patients with CVH also were elevated compared with normal controls. The levels of TGFalpha mRNA were overexpressed in the underlying livers of patients with HCC compared with patients with CVH, although they were lower than those found in HCC tissues. The levels of TGFalpha mRNA were higher in samples from patients with chronic hepatitis B than in samples from patients with chronic hepatitis C. The levels of TGFalpha mRNA were not correlated with serum alanine aminotransferase or HBV-RNA levels in liver tissues in patients with chronic hepatitis B. However, the expression of TGFalpha mRNA tended to be higher in the livers of patients with raised serum alpha-fetoprotein levels.

CONCLUSIONS

The overexpression of TGFalpha mRNA in the liver seems to be associated with the regeneration of hepatocytes rather than hepatic necrosis or viral replication. Also, it may be related closely to the development or progression of HCC, especially in the livers of patients with chronic hepatitis B.

Cellular and molecular mechanism for Kilham rat virus-induced autoimmune diabetes in DR-BB rats

Kilham rat virus (KRV) causes autoimmune diabetes in diabetes-resistant BioBreeding (DR-BB) rats; however, the mechanism by which KRV induces autoimmune diabetes without the direct infection of beta cells is not well understood. We first asked whether molecular mimicry, such as a common epitope between a KRV-specific peptide and a beta cell autoantigen, is involved in the initiation of KRV-induced autoimmune diabetes in DR-BB rats. We found that KRV peptide-specific T cells generated in DR-BB rats infected with recombinant vaccinia virus expressing KRV-specific structural and nonstructural proteins could not induce diabetes, indicating that molecular mimicry is not the mechanism by which KRV induces autoimmune diabetes. Alternatively, we asked whether KRV infection of DR-BB rats could disrupt the finely tuned immune balance and activate autoreactive T cells that are cytotoxic to beta cells, resulting in T cell-mediated autoimmune diabetes. We found that both Th1-like CD45RC+CD4+ and cytotoxic CD8+ T cells were up-regulated, whereas Th2-like CD45RC-CD4+ T cells were down-regulated, and that isolated and activated CD45RC+CD4+ and CD8+ T cells from KRV-infected DR-BB rats induced autoimmune diabetes in young diabetes-prone BioBreeding (DP-BB) rats. We conclude that KRV-induced autoimmune diabetes in DR-BB rats is not due to molecular mimicry, but is due to a breakdown of the finely tuned immune balance of Th1-like CD45RC+CD4+ and Th2-like CD45RC-CD4+ T cells, resulting in the selective activation of beta cell-cytotoxic effector T cells.

Experimental model of hepatic fibrosis following repeated periportal necrosis induced by allylalcohol

BACKGROUND/AIMS

In most patients with chronic viral hepatitis the predominant lobular location of hepatic necrosis and fibrosis is the periportal zone. We established a new simple model of hepatic fibrosis in rats by repetitive periportal necrosis with allylalcohol.

METHODS

Of 40 male adult rats, 30 were injected with 0.62 mmol/kg of allylalcohol intraperitoneally twice a week, the remaining 10 with normal saline as controls. Ten rats were killed at each of 4, 8, and 16 weeks later. The extent of fibrosis was evaluated according to the portal-portal extent. Transforming growth factor (TGF) beta1 mRNA in liver tissues was detected by reverse transcriptase polymerase chain reaction, and its levels were determined by the endpoint titers of serial two-fold dilutions of cDNA.

RESULTS

After 4 weeks, periportal fibrosis was produced in only 6 out of 10 rats, and was mild in extent. However, after 8 weeks, 8 out of 9 survivors showed moderate to severe fibrosis, which corresponded to a score of 7 or more. The extent of fibrosis correlated significantly with the amount of collagen and TGFbeta1 mRNA expression in liver tissues. The collagen content and expression of TGFbeta1 mRNA were also upregulated significantly in liver tissues with a fibrosis score of 7 or more.

CONCLUSIONS

Hepatic fibrosis can be sufficiently induced by repetitive intraperitoneal injection of 0.62 mmol/kg of allylalcohol twice a week for 8 weeks. This simple model of hepatic fibrosis, in which TGFbeta1 is overexpressed at the transcriptional level, may be useful in the study of patients who have predominantly periportal necrosis and fibrosis.

Immunohistochemical study on the distribution of six members of the Kv1 channel subunits in the rat basal ganglia

The differential expression of specialized voltage-gated potassium (Kv) channel subtypes in the nervous system probably reflects the wide range of functions. Although there have been previous reports in the cellular and subcellular localizations of various Kv mRNAs and proteins, the comprehensive study described here is the first in which the expression of six Kv1 channel subunits have been directly compared in the rat basal ganglia. In the present study, we have found that staining patterns of the six Kv1 channel subunits overlap in some areas of the basal ganglia, but each has a unique pattern of expression. It was noted that Kv 1.4 subunit had a strikingly high level of expression in the globus pallidus compared to the caudate-putamen. This distinct distribution formed the clear demarcations between caudate-putamen and globus pallidus. The dot-like staining pattern of Kv1 subunits was observed through the accumbens nucleus. Strong staining for Kv1.4 was observed in the cerebral peduncle, not in the subthalamic nucleus. In the substantia nigra, immunoreactivity for Kv1.4 subunit was prominent in the pars reticulata of the substantia nigra. The staining intensity for Kv1.2 was high in the pars compacta of the substantia nigra. Our immunohistochemical results may support the notion that the formation of heteromultimeric Kv channels possibly represents an important contribution to the generation of Kv channel diversity in the brain, especially in the basal ganglia.

Cyclophosphamide inhibits the development of diabetes in the diabetes-prone BB rat

AIMS/HYPOTHESIS

Cyclophosphamide has been shown to augment the diabetic process in NOD mouse and BB rat models of Type I (insulin-dependent) diabetes mellitus. Because cyclophosphamide has, however, been shown to increase immunoregulatory cell activity, we examined if cyclophosphamide treatment increases immunoregulatory cell activity and inhibits the diabetic process in BB rats.

METHODS

The development of insulitis and diabetes was explored in BB rats treated with saline and cyclophosphamide (60 to 175 mg/kg body weight). Subsets of spleen cells were assessed by flow cytometry and cytokine gene expression by RT-PCR. To determine if cyclophosphamide induces immunoregulatory cell activity, the development of diabetes was assessed in BB rats injected with spleen cells from rats treated with saline and cyclophosphamide.

RESULTS

All dosages of cyclophosphamide decreased the development of diabetes. The degree of insulitis was lower in pancreata from 55-day-old rats treated with cyclophosphamide than those from controls. Cyclophosphamide caused no alterations in the numbers of NK cells, T-cell subsets, or RT6.1+ T cells. The adoptive transfer of spleen cells from cyclophosphamide-treated rats to BB rats inhibited the development of diabetes. Cyclophosphamide treatment decreased IL-12, IL-1beta, IL-2, IFN-gamma and TNF-alpha gene expressions in mononuclear spleen cells but IL-4 gene expression increased.

CONCLUSION/INTERPRETATION

These findings show that cyclophosphamide treatment decreases the development of diabetes by inhibiting the development of insulitis. This inhibitory action of cyclophosphamide on the diabetic process seems to be mediated by the induction of immunoregulatory cell activity. The suppression of cytokines that promote Thl cell differentiation by cyclophosphamide treatment could also play a part in the diabetes sparing effect of cyclophosphamide.

Pattern of deposition of stainless steel welding fume particles inhaled into the respiratory systems of Sprague-Dawley rats exposed to a novel welding fume generating system

In order to investigate occupational diseases related to welding fume exposure, such as nasal septum perforation, pneumoconiosis and manganese intoxication, we built a welding fume exposure system that included a welding fume generator, exposure chamber and fume collector. The fume concentrations in the exposure chamber were monitored every 15 min during a 2-h exposure. Fume (mg/m(3)) concentrations of major metals, including Fe, Mn, Cr, and Ni were found to be consistently maintained. An acute inhalation toxicity study was conducted by exposing male Sprague-Dawley rats to the welding fumes generated in this apparatus by stainless steel arc welding. The rats were exposed in the inhalation chamber to a welding fume with a concentration of 62 mg/m(3) total suspended particulates for 4 h. Animals were sacrificed at 4 h and at 1, 3, 7, 10, and 14 days after exposure. Histopathological examinations were conducted on the animals' upper respiratory tracts, including the nasal pathway and the conducting airway, and on the gas exchange region including the alveolar ducts, alveolar sacs, and alveoli. Diameters of fume particles varied from 0.02 to 0.81 microm and were distributed log normally, with a mean diameter of 0.1 microm and geometric standard deviation of 1.42. Rats exposed to the welding fume for 4 h did not show any significant respiratory system toxicity. The mean particle diameter of 0.1 microm resulted in little adsorption of the welding fume particles in the upper respiratory tract. Particle adsorption took place principally in the lower respiratory tracts, including bronchioles, alveolar ducts, alveolar sacs, and alveoli.

Immunohistochemical study on the distribution of the voltage-gated calcium channel alpha(1B) subunit in the mature rat brain

Many neuronal processes are regulated by calcium influx through voltage-gated calcium channels. Among these calcium channels, the N-type channel has been shown to play a significant role in the regulation of neurotransmitter release. This present report has demonstrated the distribution of the alpha(1B) subunit of the N-type calcium channel in the mature rat brain. The most striking findings were the highest immunoreactivity in the CA1 region of the hippocampus and the clear demarcation in the thalamus. Characteristic patterns of distribution were noted in the cerebral cortex, hippocampus, caudate-putamen, thalamus, and cerebellum. In the cerebral cortex, strong staining was seen in layers II-III and V. In the basal ganglia, the staining intensity was high in the caudate-putamen, whereas there was no immunoreactivity in the globus pallidus. Although the staining intensity was relatively low compared to that of the forebrain, moderate alpha(1B)-IR was found in the dorsal cochlear nucleus and mesencephalic trigeminal nucleus. The detailed features of this study will extend our current knowledge of alpha(1B) subunit distribution in terms of the number of neuroanatomical areas examined, by investigating alpha(1B) subunit protein expression, for the first time.

Combined therapy consisting of intraarterial cisplatin infusion and systemic interferon-alpha for hepatocellular carcinoma patients with major portal vein thrombosis or distant metastasis

BACKGROUND

Hepatocellular carcinoma (HCC) patients with major vascular involvement or extrahepatic metastasis are not good candidates for surgery or transarterial chemoembolization (TACE). In this study, the authors evaluated the efficacy of combined therapy with intraarterial cisplatin infusion and systemic administration of interferon-alpha (IFN-alpha) as a palliative treatment for these patients.

METHODS

Sixty-eight HCC patients with major portal vein thrombosis (n = 47) or distant metastasis (n = 27) were randomly allocated to 1 of 3 groups. Group I (n = 19) received combined therapy consisting of intraarterial cisplatin infusion and systemic IFN-alpha, Group II (n = 23) received intraarterial cisplatin infusion, and Group III (n = 26) was managed with only supportive care. Cisplatin 2 mg/kg was infused through the proper hepatic artery every 8 weeks, and IFN-alpha 3 million IU/m2 was administered subcutaneously 3 times a week.

RESULTS

The partial response (defined as a 50% or greater reduction in the product of the 2 longest perpendicular tumor measurements) rate of Group I was significantly higher than that of Group II (33% vs. 14%; P < 0.05). Also, the 1-year survival rate of Group I (27%) was higher than that of Group II (9%) or Group III (0%) (P < 0.05 and P < 0.01, respectively). The median survival period of Group I was 19 weeks, which was significantly longer than that of Group II (11 weeks) or Group III (5 weeks) (P < 0.05 and P < 0.01, respectively).

CONCLUSIONS

These results suggest that combined therapy consisting of intraarterial cisplatin infusion and systemic IFN-alpha may be useful as a palliative treatment for HCC patients with major vascular involvement or extrahepatic metastasis.

Immunohistochemical study on the distribution of neuronal voltage-gated calcium channels in the rat cerebellum

Many neuronal processes are regulated by calcium influx through voltage-gated calcium channels (VGCCs), including protein phosphorylation, gene expression, neurotransmitter release, and firing patterns of action potential. In the present study, we have used anti-peptide antibodies directed against a unique sequence in rat alpha(1A), alpha(1B), alpha(1C) and alpha(1D) subunits of VGCCs to determine their cellular distribution in normal rat cerebellum. Throughout the molecular layer, immunoreactivity for alpha(1B) and alpha(1D) subunits were found in the cell bodies of basket and stellate cells as well as in the neuropil. In the Purkinje cells, only alpha(1C)-IR was observed in the dendritic branches of Purkinje cells, whereas immunoreactivity for alpha(1B) and alpha(1D) subunits were rarely found in the cell bodies of Purkinje cells. Immunoreactivity for the alpha(1A), alpha(1B,) and alpha(1D) subunits were strong in the granule cell bodies, whereas alpha(1C)-IR was not prominent in the cell bodies. In the cerebellar nuclei, a distinct band of punctate immunoreactivity for the alpha(1A), alpha(1B), alpha(1C), and alpha(1D) subunits were observed. The overall results of the above localization study showed clearly that the alpha(1A), alpha(1B,) alpha(1C) and alpha(1D) pore forming subunits of VGCCs have differential distribution in the rat cerebellum. The present studies may provide useful data for such future investigations to understand the role of calcium channels in neurological pathways.

History of the Korean GLPs and the activities and perspectives of the Korean Society of GLP

The Korean Society of Good Laboratory Practice (KSGLP) was established Dec. 10, 1998. The objectives of the KSGLP are to enhance the quality of domestic studies and the level of GLP compliance, in safety testing, and to promote information exchange among its members. The activities of KSGLP include: offering workshops and symposiums, linking with related governmental organizations, collecting GLP related information and providing the information to the related organizations, building international networks to collect information and to establish relationship, developing training materials and publishing periodicals, and other business necessary to achieve the objectives of the KSGLP. The KSGLP achieved its goals within a short period of time by offering workshops and symposia, and by providing important GLP related information in newspapers or via the KSGLP's internet homepage (www.ksglp.or.kr). The main role of the KSGLP will be to disseminate GLP technology nationwide. The KSGLP would like to help many labs that are preparing their facilities for GLP compliance. Further, the KSGLP is hoping to share GLP experiences with other members.

Region-specific changes of NOS-IR cells in the basal ganglia of the aged rat

Nitric oxide (NO) is a free radical postulated to act as a neurotransmitter, neuromodulator, or second messenger molecule in the central nervous system. Several findings suggest that NO production may be decreased in the aged rats. In the present study, we investigated regional discrepancies in changes with aging in the number of nitric oxide synthase-immunoreactive (NOS-IR) cells in the basal ganglia of the aged rat by immunocytochemistry. The number of NOS-IR neurons in the striatum and substantia innominata of the aged rat decreased. In contrast, the number of NOS-IR neurons in the subthalamic nucleus increased in the aged rat. On the other hand, the number of NOS-IR neurons in the nucleus accumbens and olfactory tubercle did not change. Taken together, important functional changes can be caused by the region-specific changes of NOS-IR neurons in the basal ganglia with aging.

Lipopolysaccharide-activated kinase, an essential component for the induction of the antimicrobial peptide genes in Drosophila melanogaster cells

Eukaryotic organisms use a similar Rel/NF-kappaB signaling cascade for the induction of innate immune genes. In Drosophila, lipopolysaccharide (LPS) signal-induced activation of the Rel/NF-kappaB family transcription factors is an essential step in the transcriptional activation of inducible antimicrobial peptide genes. However, the mechanism by which the LPS-induced signaling pathway proceeds remains largely unknown. Here we have cloned a novel Drosophila LPS-activated kinase (DLAK) that is structurally related to mammalian IkappaB kinases. DLAK is expressed and transiently activated in LPS-responsive Drosophila cells following LPS stimulation. Furthermore, DLAK can interact with Cactus, a Drosophila IkappaB and phosphorylate recombinant Cactus, in vitro. Overexpression of dominant-negative mutant DLAK (DLAK(K50A)) blocks LPS-induced Cactus degradation. DLAK-bound Cactus can be degraded in a LPS signal-dependent fashion, whereas the DLAK(K50A) mutant-bound Cactus is completely resistant to degradation in the presence of LPS. The DLAK(K50A) mutant also inhibits nuclear kappaB binding activity and kappaB-dependent diptericin reporter gene activity in a dose-dependent manner, but the kappaB-dependent diptericin reporter gene activity can be rescued by overexpression of wild type DLAK. Moreover, mRNA analysis of various kappaB-dependent antimicrobial peptide genes shows that LPS inducibility of these genes is greatly impaired in cells overexpressing DLAK(K50A). These results establish that DLAK is a novel LPS-activated kinase, which is an essential signaling component for the induction of antimicrobial peptide genes following LPS treatment in Drosophila cells.

Immunocytochemical study on the distribution of nitrotyrosine in the brain of the transgenic mice expressing a human Cu/Zn SOD mutation

In the previous study, we reported increased NOS expression in the astrocytes in the spinal cord of the transgenic mice that are used as ALS animal model. In the present study, we performed immunocytochemical studies to investigate the changes of nitrotyrosine-immunoreactivity in the brains of the transgenic mice, and demonstrated in vivo evidence of peroxynitrite-mediated oxidative damage in the pathogenesis of ALS. In the spinal cord of the transgenic mice, immunocytochemistry showed intensely stained nitrotyrosine-IR glial cells with the appearance of astrocytes, but no nitrotyrosine-IR glial cells were observed in the spinal cord of the control mice. In the transgenic mice, nitrotyrosine-IR neurons were observed in the hypoglossal nucleus, lateral reticular nucleus, medullary reticular formation and cerebellar nuclei. Interestingly, nitrotyrosine-IR neurons were observed in the hippocampal formation and septal area of the transgenic mice. In the hippocampus, nitrotyrosine-IR neurons in the CA1 region showed intense staining, and the immunoreactivity was localized mainly in the pyramidal cell layer. Recent studies have shown that antioxidants and selective neuronal NOS inhibitor increase survival in the SOD1 transgenic mouse model of FALS. It is possible that therapy with these agents may slow the neurodegenerative process in human ALS, perhaps through reduction of nitrotyrosine formation.

Reactive astrocytes express p53 in the spinal cord of transgenic mice expressing a human Cu/Zn SOD mutation

In a previous study, we reported increased NOS expression in the astrocytes in the spinal cord of SOD mutant transgenic mice that are used as ALS animal model. Recently, Messmer and Brune suggested that nitric oxide-induced apoptosis is intimately related with p53-dependent signaling pathway, and de la Monte et al. reported increased p53-immunoreactivity in the spinal cord of ALS patients. In the present study, we performed immunocytochemical studies to investigate the changes of p53-immunoreactivity in the brains of the mutant transgenic mice expressing a human Cu/Zn SOD mutation. Immunocytochemistry showed intensely stained p53-IR glial cells with the appearance of astrocytes in all levels of the spinal cord of the mutant transgenic mice, but no p53-IR glial cells were observed in the spinal cord of the control mice. P53-IR astrocytes were also detected in the brain stem of the mutant transgenic mice. In the medulla, they were observed in the medullary reticular formation, hypoglossal nucleus, vestibular nucleus, dorsal motor nucleus of the vagus and nucleus ambiguus. In the pons, their presences were noted in the pontine reticular formation, and trigeminal and facial nuclei. In the midbrain, astrocytes were detected in the mesencephalic reticular formation, red nucleus and periaqueductal gray matter. In the cerebellum, intensely stained p53-IR astrocytes were detected in the intracerebellar nuclei. In contrast to the mutant transgenic mice, no p53-IR astrocytes were detected in the brain stem and spinal cord of the control mice. Further multidisciplinary investigations involving p53-mediated cellular damage and pathogenesis of ALS are needed to clarify the importance of these results.

Characterization of the anticancer activity of DW2282, a new anticancer agent

DW2282 [(S)-(+)-4-phenyl-1-[N-(4-aminobenzoyl) indoline-5-sulfonyl]-4,5-dihydro-2-imidazolone].hydrochloride] was derived from diarylsulfonylurea and was identified as a prominent new anticancer agent. We examined the characteristics of DW2282 activity on the proliferation of human lung carcinoma cells, A549 and human leukemic cells, K562. DW2282 effectively inhibited cancer cell proliferation in vitro. Colony forming assay and viability tests demonstrated that DW2282 is a cytotoxic agent rather than a cytostatic agent. The isotope uptake test exhibited that DW2282 inhibited or inactivated protein synthesis. Also, under conditions which cause RNA or protein synthesis inhibition, by co-treatment with actinomycin D or cycloheximide, reduced the anticancer effects of DW2282. This means that the cytotoxicity of DW2282 depends partially on RNA or protein synthesis and proteins affected by DW2282 may inactivate or alter the process of the synthesis of another protein. DW2282 activity was highly diminished in the presence of colcemid, a metaphase spindle blocker. This result suggests that DW2282 may be related to the cell cycle. After exposure to DW2282, morphologically apoptotic cells appeared in A549 cells and fragmented DNA was detected in K562 cells. It demonstrated that apoptosis is one of the mechanisms by which DW2282 inhibits the proliferation of A549 and K562 cells.

Co-administration of toluene and xylene antagonized the testicular toxicity but not the hematopoietic toxicity caused by ethylene glycol monoethyl ether in Sprague-Dawley rats

Occupational painters are exposed to ethylene glycol monoethyl ether (EGEE), a widely used emulsifying solvent known to cause testicular degeneration and bone marrow depression, together with toluene (TOL) and xylene (XYL) as a mixture. In the previous study (Chung et al., Tox. Lett. 104:143, 1999), testicular atrophy caused by EGEE (200 mg/kg) was shown to be antagonized by co-administration of TOL (250 mg/kg) and XYL (500 mg/kg). This study was conducted to provide histological support for the previously observed antagonistic protective effect of TOL + XYL on EGEE inducible testicular toxicity and to determine whether a similar antagonistic effect can be demonstrated against the EGEE derived hematopoietic toxicity. Compared to the extent of seminiferous tubule degeneration caused by EGEE (150 mg/kg, six times per week for 4 weeks), testes of rats given co-administration of TOL (250 mg/kg) + XYL (500 mg/kg) showed dramatically reduced tubular degeneration. Hyperplasia of Leydig cells in the interstitium was observed in both EGEE and EGEE + TOL + XYL-treated rats. Although a minimal dose of EGEE causing testicular atrophy was used, WBC and platelet counts were decreased significantly. In the TOL + XYL-treated control group, the WBC and platelet counts were not decreased. However, the bone marrow depression caused by EGEE was not reversed by the combined administration of TOL + XYL. In all experimental groups (EGEE alone, TOL + XYL, EGEE + TOL + XYL), plasma levels of creatinine and alkaline phosphatase were significantly decreased. In addition to the marked testicular atrophy, EGEE also decreased the weights of adrenal glands and epididymis. In conclusion, while the testicular degeneration caused by EGEE was antagonized by TOL + XYL, the EGEE derived hematopoietic suppression was not reversed.

Hepatocellular carcinoma not related to hepatitis B virus infection among Alaska natives

Chronic infection with hepatitis B or C viruses is a common underlying condition in patients with hepatocellular carcinoma worldwide. We studied serum and liver tissue from a cohort of Alaska natives with hepatocellular carcinoma (HCC) for evidence of hepatitis B, C and G viral infection using conventional serological tests as well as the sensitive polymerase chain reaction. Evidence of HBV infection was found in 25 and possible HCV infection in two cases. Among the remaining 11 patients, four had a history of recent or remote alcoholism while seven had no recognizable risk factors for HCC. Only one was seropositive for HGV RNA and that was an individual with a history of alcoholism. Non-tumorous liver tissue was available for study in six of these seven cases. Histological features of chronic hepatitis were present in five. Thus, at least five of 38 (13%) Alaska natives with HCC appeared to have chronic hepatitis not related to HBV or HCV infection, suggesting the possibility of some form of previously unrecognized chronic liver disease predisposing to HCC.

Photomovement of the gliding cyanobacterium Synechocystis sp. PCC 6803

Using a computerized videomicroscope motion analysis system, we investigated the photomovements of two Synechocystis sp. (PCC 6803 and ATCC 27184). Synechocystis sp. PCC 6803 displays a relatively slow gliding motion. The phototactic and photokinetic speeds of this cyanobacterium in liquid media were 5 microns/min and 15.8 microns/min, respectively, at 3 mumol/m2/s of stimulant white light. Synechocystis sp. PCC 6803 senses light direction rather than intensity for phototaxis. Synechocystis sp. ATCC 27184 showed a weak photokinesis but no phototaxis. Analysis of Synechocystis sp. ATCC 27184 suggests that the loss of phototaxis results from spontaneous mutation during several years of subculture. When directional irradiation was applied, the cell population of Synechocystis sp. PCC 6803 began to deviate from random movement and reached maximum orientation at 5 min after the onset of stimulant white light. Synechocystis sp. PCC 6803 showed high sensitivity to the stimulant white light of fluence rates as low as 0.002 mumol/m2/s. Neither 1,3-dichlorophenyldimethyl urea nor cyanide affected phototactic orientation, whereas cyanide inhibited gliding speed. This result suggests that the phototaxis of Synechocystis sp. PCC 6803 is independent of photosynthetic phosphorylation and that its gliding movement is primarily powered by oxidative phosphorylation. In the visible wavelength region, 560 nm, 660 nm and even 760 nm caused positive phototaxis. However, 360 nm light induced strikingly negative phototaxis. Therefore, at least two independent photoreceptors may exist to control phototaxis. The photoreceptor for positive phototaxis appears likely to be a phytochrome-like tetrapyrrole rather than chlorophyll a.

Percutaneous hot saline injection therapy: effectiveness in large hepatocellular carcinoma

PURPOSE

To report on the efficacy of percutaneous hot saline injection therapy (PSIT) in the treatment of large hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Twenty-nine patients with 31 HCCs underwent PSIT. Physiologic saline was mixed with contrast medium and Lipiodol; this mixture was boiled and injected into the tumor. Mean tumor diameter was 7.0 cm. Initial regression rates were evaluated at 3-month interval with computed tomography (CT) and alpha-fetoprotein level measurement. Cumulative survival rates were calculated with the Kaplan-Meier method. Multivariate analysis using Cox's proportional hazard regression model was performed to determine the significant prognostic factors.

RESULTS

Initial regression rate for all tumors at a 3-month interval was 42% (13 of 31 tumors) and the median survival was 10.0 months (range, 3.0-36.0 months). The significant prognostic factors were encapsulated tumors, tumors less than 10 cm in diameter, tumors with even saline dispersion, tumors with initial regression at 3-month follow-up, and TNM stage II or III rather than IV.

CONCLUSION

PSIT is a feasible alternative treatment for a large HCC when transcatheter arterial chemoembolization is not feasible or has failed.

Colonic wall thickening in cirrhotic patients: CT features and its clinical significance

BACKGROUND

To evaluate the computed tomographic (CT) features of colonic wall thickening in cirrhotic patients and to determine their prognostic value.

METHODS

We retrospectively reviewed 28 cirrhotic patients with colonic wall thickening (>/=10 mm) on CT. Twenty-six of the 28 patients had hepatocellular carcinoma. The severity of hepatic dysfunction was determined by using the Child-Pugh classification. We analyzed the patterns of bowel wall thickening and degree of portal hypertension on CT and the survival periods after initial CT detection of colonic wall thickening.

RESULTS

The involved segment of the colon was diffusely thickened with either scalloped or nodular circumferential configuration. In all patients, the thickened colonic wall enhanced poorly. Although the ascending colon was involved in all patients, the transverse (n = 14) or descending (n = 5) colon was also simultaneously involved. Most patients exhibited an advanced stage of portal hypertension on CT. The median survival period of 25 patients who expired was 34 days, and 21 patients (84%) expired within 3 months.

CONCLUSIONS

Colonic wall thickening on CT can be used as one of the indicators of poor prognosis in cirrhotic patients. Advanced liver cirrhosis with significantly severe dysfunction is the likely cause of mortality. Therefore, a less aggressive therapeutic approach is recommended if hepatocellular carcinoma is coexistent in these patients.

c-Fos basal immunoreactivity decreases in rat spinal cord during normal ageing

The pattern of distribution in rat spinal cord and changing pattern during normal ageing of c-Fos expression were investigated by immunohistochemical staining in male Sprague-Dawley rats at the age of 1 week, 5 months and 2 years. c-Fos immunoreactivity was observed diffusely in gray matters in neonatal rats, preferentially located in deep dorsal horn and around central canal. Compared with those of neonatal rats, these cells decreased prominently in adult rats. In aged rats, immunoreactive cells were not seen in any segments. c-Fos immunoreactivity in spinal cord may be related to stress response, functional differentiation, and in part, neuronal death with target dependence. In conclusion, we demonstrated for the first time that c-Fos expression patterns change during normal ageing.

Endobronchial metastasis of glioblastoma multiforme diagnosed by fiberoptic bronchoscopic biopsy

We report a case of extraneural metastasis of an intracranial glioblastoma multiforme (GBM) to the left upper lung, in which fiberoptic bronchoscopy played a key role in the diagnosis. The patient, a 20-year-old woman, presented with dry cough and hoarseness 2 years after total excision of the brain tumor and postoperative radiotherapy. Tissue samples obtained during fiberoptic bronchoscopic biopsy had the same morphologic appearance as the primary intracranial tumor, which was consistent with GBM. In cases of pulmonary metastasis of GBM, antemortem diagnosis is rare. Our experience from this case suggests that fiberoptic bronchoscopy may be a valuable diagnostic tool for metastatic GBM.

Immunomodulating activity of DW-116, a new quinolone antibiotic

DW-116, (1-(5-fluoro-2-pyridyl)-6-fluoro-7-(4-methyl-1-piperazinyl)-1, 4-dihydro-4-oxoquinoline-3-carboxylic acid hydrochloride), is a new quinolone antibiotic with a broad antibacterial spectrum against G(+) and G(-) bacteria. DW-116 was evaluated for the immunomodulating activities, which is one of the efforts to investigate the mechanism of action related to the good in vivo antibacterial efficacy. The results of in vitro studies revealed there was no statistically significant increase in B and T lymphocyte proliferation. But the results of in vivo studies showed that the number of plaque forming cells (PFC), the amount of polyclonal antibodies and delayed-type hypersensitivity (DTH) were significantly increased after the repeat administration with 12 and 60 mg/kg of DW-116. Taken together, these results proposed that immunostimulating effect of DW-116 could be one of the action mechanisms for demonstrating in vivo antibacterial activities under these experimental conditions.

Safety, tolerability and pharmacokinetics of the new long-acting quinolone DW-116 after single and multiple dosing in healthy subjects

The safety, tolerability and pharmacokinetics of DW-116, a new fluoroquinolone with a broad antibacterial spectrum, were evaluated in healthy male subjects after administration of single oral doses of 100, 200, 300 and 800 mg and after administration of multiple oral doses of 300 or 400 mg, respectively, for 7 days. DW-116 was well tolerated. Gastrointestinal symptoms and skin reactions were noted and considered to be possibly related to DW-116. The geometric means of the maximum plasma concentrations (Cmax) linearly increased with the dose administered from 1.19 mg/L to 8.73 mg/L after single dose administration. At steady state, the geometric mean minimum and maximum plasma concentrations were 2.14 and 5.65 mg/L, respectively, after the multiple 300 mg dose and 2.73 and 8.00 mg/L, respectively, for the multiple 400 mg dose. Tmax varied between 1 and 5 h. The terminal half-life ranged from 11.37 to 24.89 h. The geometric mean renal clearance was approximately 30 mL/min. Approximately 45% of the dose was excreted unchanged in urine within 60 h. There was no clinically relevant deviation from dose proportionality. The changes in steady-state pharmacokinetic parameters when DW-116 was taken before a high-fat breakfast were not clinically relevant. In conclusion, DW-116 was safe in this study, the first administration to human subjects. Its pharmacokinetics indicate that once-daily dosing may be possible.

Homocysteine stimulates the production and secretion of cholesterol in hepatic cells

Homocysteinemia and hypercholesterolemia are important risk factors associated with the occurrence of arteriosclerotic vascular diseases. A positive correlation between plasma levels of homocysteine and cholesterol was found in homocysteinemic patients as well as in experimental animals. In the present study, the effect of homocysteine on the production and secretion of cholesterol in human hepatoma cell line HepG2 cells was investigated. When cells were incubated with 4 mM homocysteine, the amounts of total cholesterol produced as well as the cholesterol secreted by these cells were significantly increased (from 32 +/- 5 to 74 +/- 5 nmol/mg cellular protein). Further biochemical analyses revealed that the increase in cholesterol was resulted from an enhancement in the production and secretion of the unesterified cholesterol with no concomitant change in the level of cholesteryl esters. The activity of intracellular 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase was markedly elevated by 131% and 190% after cells were incubated with homocysteine for 24 and 48 h. Homocysteine also stimulated the secretion of apo B100 by HepG2 cells (from 0.84 +/- 0.11 to 1.37 +/- 0.12 micrograms apolipoprotein B/mg cellular protein). Our results demonstrate that homocysteine stimulates the production and secretion of cholesterol and apolipoprotein B100 in HepG2 cells. The increase in the production of cholesterol induced by homocysteine may contribute to the pathogenesis of arteriosclerosis.

Low dose poly I:C prevents diabetes in the diabetes prone BB rat

Poly I:C, an inducer of IFN-alpha and other cytokines, has been used to study the development of diabetes in both the BioBreeding (BB) diabetes prone rat and non-obese diabetic (NOD) mouse animal models of insulin-dependent diabetes mellitus (IDDM). Surprisingly, poly I:C accelerates the disease in the BB rat while inhibiting it in the NOD mouse. Since cytokines can have dose related opposing effects on immune responses, we hypothesized that the paradoxical effect of polyinosinic polycytidylic acid (poly I:C) on diabetes in the two animal models is dose related. Accordingly, we compared the incidence of diabetes and degree of insulitis in diabetes prone BB rats administered saline and poly I:C at doses (0.05 microg/g body weight and 0.1 microg/g body weight) up to 100-fold lower than doses (poly-5 microg/g) previously found to accelerate diabetes. In addition, the non-specific suppressor activity of mononuclear splenocytes from BB rats administered low dose (poly-0.05 microg/g body weight), high dose (poly-5 microg/g body weight), and saline were compared. The development of diabetes was inhibited in rats treated with each dose of poly I:C. The degree of insulitis in poly-I:C treated animals was also less severe. The total white blood cell count and proportion of RT6+ T-cells and each T-cell subset were unaltered by poly I:C. When compared to splenocytes of control animals, splenocytes from poly I:C (0.05 microg/g body weight) treated rats suppressed responder cell proliferation to concanavalin A and alloantigen. However, spleen cells from high dose poly-I:C did not suppress responder cell proliferation to alloantigen. In adoptive transfer studies, the administration of spleen cells from poly-0.05 treated rats decreased the development of diabetes in recipient BB rats. In vitro studies also demonstrated that poly-I:C inhibits the proliferative response of BB rat spleen cells to concanavalin A. The administration of poly-0.05, but not poly-5.0, decreased TNF-alpha mRNA and IL-10 mRNA content in spleen cells. We conclude that poly I:C, at a dose 100 times lower than that required to accelerate diabetes prevents the development of diabetes in BB rates by interfering with the development of insulitis. The induction of suppressor cell activity induced by low dose poly-I:C in vivo and the inhibition of T-cell responses by poly-I:C in vitro suggests that the diabetes sparing activity of poly I:C is mediated by augmented immunoregulatory cell activity. Further studies with poly I:C may be important in increasing our understanding of the pathogenesis of IDDM and provide a means to prevent it.

Immunocytochemical study on the distribution of NOS-immunoreactive neurons in the cerebral cortex of aged rats

Nitric oxide (NO) involvement has been demonstrated in mechanisms of synaptic plasticity, particularly in hippocampal long-term potentiation, a mechanism that underlies certain forms of learning and memory. Several findings suggest that NO production may be decreased in the aged rats. Changes in the nNOS-containing neurons with ageing were demonstrated by immunocytochemistry. NOS-immunoreactive (IR) cells in aged rats were present in all cortical areas and the hippocampus, and the pattern of distribution was similar to that of the control group. The number of NOS-IR cells in the cerebral cortex was significantly decreased in the aged rats, but the extent of changes was variable in each area, and ranged from mild decrease (< 30%) to severe decrease (> 50%). Severely decreased areas were the cingulate cortex, parietal cortex area 1, temporal cortex area 1, 2, 3, medial part of occipital cortex area 2, monocular and binocular part of occipital cortex area 1, entorhinal cortex, hippocampus proper, dentate gyrus and subiculum. Morphologically, the number of dendritic branches seemed to be decreased in aged group and the length of dendrites of NOS-IR neurons showed a tendency to shorten. These results indicate the involvement of neuronal system containing NOS in the ageing brain, and provide the first morphological evidence for the loss of NOS neurons in the cerebral cortex of the aged rats by immunocytochemistry.

Synthesis and antitumor activity of 4-phenyl-1-arylsulfonyl imidazolidinones

Novel 1-(1-benzoylindoline-5-sulfonyl)-4-phenyl-4,5-dihydroimidazolon es 3 synthesized show highly potent and broad cytotoxicities. Among them compound 3b (DW2143) exhibits much more potent cytotoxicities than doxorubicin and highly effective antitumor activities against murine (3LL, Colon 26) and human xenograft (NCI-H23, SW620) tumor models.

Toxicities of 166Holmium-chitosan in mice

166Holmium (166Ho) is a radionuclide of rare earth chemical and is known to have antitumor activity. Several chemicals were complexed with 166Ho to facilitate the transport of this radionuclide to the site of action. In this study, 166Ho was complexed to chitosan (Chit) which decreases the distribution of Ho into other tissues when applied intrahepatically. To investigate the single dose toxicity, mice were administered intravenously with 1 mCi/kg body weight of 166Ho-Chit (DW-166HC), Chit or nothing. Organ weights, hematological and histopathological studies were performed in 6 animals per group at 1, 3 and 14 days after administration. In 166Ho-Chit treated animals, a slight decrease of erythrocyte number was observed at day 14 and increases of relative liver and lung weights were found at day 3. Although marked multiple necrotic foci in the white pulp and depletion of marginal zone in the spleen were noted at day 1, these findings were decreased in severity and fully recovered at day 3 and day 14, respectively. Slightly decreased kidney weights were observed both in Chit and in 166Ho-Chit treated groups without histological alterations. Thus it is suggested that most effects of 166Ho-Chit observed at an early stage after administration are limited to rapidly dividing cells and reversible within 14 days.

Cloning and characterization of two catA genes in Acinetobacter lwoffii K24

Two novel type I catechol 1,2-dioxygenases inducible on aniline media were isolated from Acinetobacter lwoffii K24. Although the two purified enzymes, CD I1 and CD I2, had similar intradiol cleavage activities, they showed different substrate specificities for catechol analogs, physicochemical properties, and amino acid sequences. Two catA genes, catA1 and catA2, encoding by CD I1 and CD I2, respectively, were isolated from the A. lwoffii K24 genomic library by using colony hybridization and PCR. Two DNA fragments containing the catA1 and catA2 genes were located on separate regions of the chromosome. They contained open reading frames encoding 33.4- and 30.4-kDa proteins. The amino acid sequences of the two proteins matched well with previously determined sequences. Interestingly, further analysis of the two DNA fragments revealed the locations of the catB and catC genes as well. Moreover, the DNA fragment containing catA1 had a cluster of genes in the order catB1-catC1-catA1 while the catB2-catA2-catC2 arrangement was found in the catA2 DNA fragment. These results may provide an explanation of the different substrate specificities and physicochemical properties of CD I1 and CD I2.

Reproductive toxicity of 2-bromopropane in Sprague Dawley rats

OBJECTIVES

In an effort to clarify the mass intoxication of workers at an electronic company in Korea, the possible causative chemical for reproductive toxicity, 2-bromopropane (2BP), was investigated.

METHODS

2BP was tested through the use of repeated dose experiments among male Sprague Dawley rats. Ten rats were assigned to each treatment group. Vehicle control olive oil and 2BP concentrations of 125 mg/kg, 250 mg/kg, and 500 mg/kg were injected into the intraperitoneum on 28 consecutive days.

RESULTS

The rats showed significant decreases in body weight depending on the 2BP dose. The right and left testes showed typical weight loss depending on the dose of 2BP. The red blood cells, hemoglobin, and hematocrit showed some degree of decline with the high dose. The amount of hemoglobin, the mean platelet volume, the number of white blood cells, and the number of lymphocytes decreased significantly with the high dose, while the number of granulocytes and monocytes had a tendency to decrease depending on the dose of 2BP. The histopathology of the testes treated with the middle and high 2BP dose showed a typical patch appearance with severely depleted atrophic tubules, exhibiting germ cell necrosis of spermatogonia and spermatocytes in the seminiferous tubules. Leydig cell hyperplasia or hypertrophy in the interstitial tissue was also noticeable. The epididymis showed some degree of atrophy with vacuolization of the epididymal epithelium.

CONCLUSIONS

The testes are the main target organs tested for 2BP toxicity. 2BP also affect the hematopoietic system and thus induces leukopenia and normocytic anemia. Besides the reproductive organs and the hematopoietic system, no significant toxicity has been found.

Role of macrophages and macrophage-derived cytokines in the pathogenesis of Kilham rat virus-induced autoimmune diabetes in diabetes-resistant BioBreeding rats

The diabetes-resistant BioBreeding (DR-BB) rat, derived from diabetes-prone forebears, does not normally develop spontaneous insulitis or diabetes, but when infected with Kilham rat virus (KRV) this animal develops autoimmune diabetes similar to the diabetes-prone BioBreeding (DP-BB) rat. In this study, we attempted to determine whether macrophages and macrophage-derived cytokines play a role in the development of KRV-induced diabetes in DR-BB rats. Seventy-eight percent of DR-BB rats treated with KRV and poly(I:C) develop diabetes, whereas depletion of macrophages with liposome-encapsulated dichloromethylene diphosphonate (lip-Cl2MDP) in KRV and poly(I:C)-treated DR-BB rats results in the near-complete prevention of insulitis and diabetes. Measurement of the macrophage-derived cytokines IL-12, TNF-alpha, and IL-1beta revealed a selective increase of their expression, after KRV infection, in the splenic lymphocytes and the pancreatic islets. Measurement of CD4+ T cell-derived cytokines revealed that IL-2 and IFN-gamma cytokine gene expression closely correlates with an elevation of IL-12, but IL-4 and IL-10 do not change. Depletion of macrophages before the isolation of splenic lymphocytes from DR-BB rats treated with KRV and poly(I:C) resulted in the loss of ability to transfer diabetes to young DP-BB rats. On the basis of these observations, we conclude that macrophages and macrophage-derived cytokines play a critical role in the cascade of events leading to the destruction of pancreatic beta cells, culminating in the development of insulin-dependent diabetes mellitus.

Role of macrophages and macrophage-derived cytokines in the pathogenesis of Kilham rat virus-induced autoimmune diabetes in diabetes-resistant BioBreeding rats

The diabetes-resistant BioBreeding (DR-BB) rat, derived from diabetes-prone forebears, does not normally develop spontaneous insulitis or diabetes, but when infected with Kilham rat virus (KRV) this animal develops autoimmune diabetes similar to the diabetes-prone BioBreeding (DP-BB) rat. In this study, we attempted to determine whether macrophages and macrophage-derived cytokines play a role in the development of KRV-induced diabetes in DR-BB rats. Seventy-eight percent of DR-BB rats treated with KRV and poly(I:C) develop diabetes, whereas depletion of macrophages with liposome-encapsulated dichloromethylene diphosphonate (lip-Cl2MDP) in KRV and poly(I:C)-treated DR-BB rats results in the near-complete prevention of insulitis and diabetes. Measurement of the macrophage-derived cytokines IL-12, TNF-alpha, and IL-1beta revealed a selective increase of their expression, after KRV infection, in the splenic lymphocytes and the pancreatic islets. Measurement of CD4+ T cell-derived cytokines revealed that IL-2 and IFN-gamma cytokine gene expression closely correlates with an elevation of IL-12, but IL-4 and IL-10 do not change. Depletion of macrophages before the isolation of splenic lymphocytes from DR-BB rats treated with KRV and poly(I:C) resulted in the loss of ability to transfer diabetes to young DP-BB rats. On the basis of these observations, we conclude that macrophages and macrophage-derived cytokines play a critical role in the cascade of events leading to the destruction of pancreatic beta cells, culminating in the development of insulin-dependent diabetes mellitus.

In-vivo study on the harmful effect of the extremely low frequency unipolar pulsating magnetic field in mice

We studied the biological effect of a magnetic field on murine brain and kidney. Magnetic field we used was generated by Magno-DR apparatus (Hanil Co., Korea) which produced a high density unipolar square pulsating magnetic field, about 0.3 approximately 0.5 Tesla at 7 Hertz. Animals were placed in the chamber of the machine for various times from 4 hours to 24 hours. Histological sections of brain and kidney were made after perfusion fixation with paraformaldehyde. The light microscopic examination showed eosinophilic change of cytoplasm and positive immunohistochemical reaction to amyloid precursor protein in the neurons of the cerebral cortex. However, the thalamus and brain stem were less affected. The changes in the brain was seen in the mouse exposed more than 12 hours. The renal tubular epithelium showed degenerated tubules scattered in cortical area but little change was noted in glomeruli in the cortex and collecting tubules in the medulla. Immunohistochemistry of the kidney showed weakly positive reaction for the amyloid precursor protein in the distal tubular epithelium after 4 hours of exposure. These data suggest that strong pulsating magnetic fields could induce deleterious effect on the murine brain tissue and renal cortical tubules.

Effects of 2-bromopropane on the female reproductive function in Sprague-Dawley rats

2-Bromopropane (2BP) has been implicated to be the reason for the mass intoxication of workers at an electronic company in Korea. A case series study indicated that 2BP was the possible causative chemical for reproductive toxicity, causing severe anemia accompanied by amenorrhea among female workers, and azoospermia or oligospermia among male workers. To clarify the effect of 2BP on the female reproductive function, repeated doses of 2BP were tested on female Sprague-Dawley rats for 21 days. Ten rats were assigned to each treatment group. The rats were maintained in a 12 hr: 12 hr light-dark cycle and vaginal smears were monitored daily for 3 cycles. After the rats had completed 3 estrous cycles, vehicle control olive oil, 300 mg, 600 mg, and 900 mg/kg of 2BP were injected into intraperitoneum for 14 days. The female rats were then mated with male rats on a 1:1 ratio basis. The treatment continued for an additional 7 days. Rats treated with 2BP experienced a significant decrease in body weight gain depending on the dose of 2BP. The estrous cycles of the rats continued at a normal duration of time before the initiation of treatment, showing 4.32 days for the control group, 4.79 days for the low dose, 4.63 days for the middle dose, and 4.75 days of estrous cycle for the high dose group. 2BP treatment, however, induced a significant delay of the estrous cycle in the high dose treated group, showing 11.1 +/- 3.82 days of the estrous cycle. 2BP decreased the fertility and tended to decrease in the number of pups born, depending on the dose. A 900 mg/kg treatment of 2BP decreased ovarian weight, but 2BP did not affect the length of gestation. Our results indicated that 2BP seemed to be the causative agent for amenorrhea observed in female workers.

Treatment of hepatitis B virus associated glomerulonephritis with recombinant human alpha interferon

To evaluate the therapeutic effect of recombinant human alpha-interferon (alpha-IFN) on hepatitis B virus associated glomerulonephritis (HBV-GN) and the relationship between the seroconversion of viral antigens and the change of proteinuria, the hepatitis B viral markers and urinary protein were monitored during alpha-IFN treatment in 8 male adult patients who (1) were positive in serum HBsAg and HBeAg, (2) had chronic hepatitis, (3) had persistent proteinuria > 1 g/day, and (4) showed glomerulonephritis on kidney biopsy. alpha-IFN was given at a dose of 3 million units, subcutaneously, three times a week for 6 months. Kidney biopsy specimens showed membranoproliferative glomerulonephritis (MPGN) in 4 patients, mesangial proliferative glomerulonephritis (MesPGN) in 2, and membranous glomerulonephritis (MGN) in 2 patients. Seven of the 8 patients received a 6-month course of alpha-IFN therapy; 1 patient with MGN quitted therapy 2 months after the initial dose because of side effects. In 5 of the 7 patients who received a 6-month therapy, serum HBeAg disappeared, and anti-HBe appeared during the therapy. In 2 of these 5 patients, HBeAg reappeared, in 1 during alpha-IFN therapy and in 1 9 months after the last dose of alpha-IFN. The hepatitis B viral markers of the patient who received a 2-month therapy did not change. HBs antigenemia persisted in all patients. In all 4 patients with MPGN, serum HBeAg was transiently or persistently converted to negative, but the proteinuria persisted. Both patients with MesPGN showed remission of proteinuria; however, only 1 patient had seroconversion of HBeAg. In 2 patients with MGN, proteinuria persisted. In conclusion, alpha-IFN at the doses given was not effective in MPGN type of HBV-GN. Improvement of proteinuria was achieved in MesPGN patients without disappearance of HBs antigenemia which is the finding against the possible role of HBsAg in the pathogenesis of this type of HBV-GN.

Pathogenesis of chronic liver disease in patients with chronic hepatitis B virus infection without serum HBeAg

Chronic hepatitis B in patients lacking hepatitis B e antigen has been attributed to a hepatitis B virus variant (G-to-A mutation at nucleotide 1896 in the precore region of the genome). We therefore assessed the frequency and significance of this variant among 43 United States patients (10 with chronic hepatitis B seropositive for e antigen, 19 seronegative for e antigen, and 14 healthy carriers). Sera were tested for HBV DNA by polymerase chain reaction and branched DNA assay. The A1896 variant was detected by direct sequencing and ligase chain reaction. Serum HBV DNA was more frequently found among patients with e antigen-positive than e antigen-negative chronic hepatitis B. Viral titers were generally higher in those with e antigen. None of the e antigen-positive and only 24% of e antigen-negative patients harbored the A1896 variant. Patients infected with the variant were more often Asian, had had hepatitis B for longer and had higher levels of viral DNA than HBeAg-negative patients with the wild-type virus. The A1896 variant was found exclusively in patients infected with HBV genotypes C and D. Thus, the A1896 variant is uncommon in the United States. The activity of liver disease appears to be more closely related to the level of HBV replication than the presence of mutations at nucleotide 1896 in the genome.

Color Doppler flow imaging of hepatocellular carcinomas. Comparison with metastatic tumors and hemangiomas by three-step grading for color hues

The role of color Doppler imaging was evaluated in differentiating hepatocellular carcinomas (HCCs) from metastases and hemangiomas by the amount of tumoral color signals. Intratumoral and peritumoral color signals were analyzed by a three-step grading system (grade 1 to 3) in 51 patients (32 HCCs, seven metastases, and 12 hemangiomas). Correlation of grading scores for intratumoral and peritumoral color signals was evaluated with the size of the tumors as well. HCCs demonstrated a higher grade of intratumoral color signals than did metastases or hemangiomas in all (p < 0.05) and biopsy-proved lesions (p = 0.0084); there was no significant difference in the degree of peritumoral color signals in all (p > 0.05) or 17 biopsy-proved HCCs (p = 0.2078) from the other tumor groups. In addition, the grade of both intratumoral and peritumoral color signals was not related with the tumor size in all groups (p > 0.05). In conclusion, color Doppler imaging provided a valuable role in the diagnosis of HCCs based on the qualitative analysis of the intratumoral color signals.

LC50 of 2-bromopropane

LC50 of 2-bromopropane was reexamined by using the OECD guideline in ICR mouse. The mice, 3 males and 3 females, were exposed to 2-bromopropane at five different concentrations for 4 h in inhalation chambers. The exposed animals were observed for 14 days. The animals which had survived and died were counted for the LC50 determination. The LC50 was calculated by using a dose-mortality curve at a 95 percent confidence level. The LC50 was 31,171 ppm, and the lowest lethal concentration (LLC) was lower than 29,528 ppm and the lethal concentration at 100% (LC100) was higher than 32,905 ppm.

Elevation of serum type IV collagen in liver cancer as well as liver cirrhosis

Studies on the level of serum type IV collagen (IV C) have usually been focused on the disease with diffuse hepatic fibrosis. To investigate whether serum level of IV C was predictive for the development of liver cancer as well as liver cirrhosis, serum IV C level was measured by a one-step sandwich enzyme immunoassay. The mean level of serum IV C was 73.3 +/- 31.3 ng/ml in 48 controls. The levels (ng/ml) of IV C were 396.4 +/- 254.9, 429.6 +/- 320.7, 420.6 +/- 322.8, and 362.9 +/- 247.4 respectively in 11 patients with chronic hepatitis, 11 with liver cirrhosis, 16 with hepatocellular carcinoma (HCC) with cirrhosis, 10 with HCC without cirrhosis, and 10 with metasatic liver cancer, which were significantly higher than that in controls (p < 0.05). Serum IV C levels were also evaluated using a cut-off value which was determined as the mean plus two standard deviations in the controls, 136 ng/ml. The elevations above the cut-off value were observed in 91, 100, 80, and 90% respectively of 11 patients with cirrhosis, 16 with HCC with cirrhosis, 10 with HCC without cirrhosis, and 10 with metastatic liver cancer, while only one (9%) of 11 chronic hepatitis patients and none (0%) of 48 controls had elevated levels. The levels of serum IV C were analysed with regard to age, sex, serum levels of albumin, globulin, transaminases, alpha-fetoprotein, and diameter of liver mass, a significant difference being observed only between the diameter of HCC and serum level of IV C (p < 0.01). These results indicate that the measurement of serum IV C is a useful for the determination of primary and metastatic liver cancer as well as liver cirrhosis.

[A study on menopausal symptoms and health needs among middle aged women]

During the middle age of a woman's life cycle, several health changes and problems occur. Therefore, middle aged women must manage their health and maintain quality life by coping with bodily changes. However, today there is not enough research and health programs for middle aged women. Data from the study will be used for health promotion program development of middle aged women. Data was collected from January 21 to 24, 1995 by telephone interview. Four hundred middle aged women between 40 and 59 years old and living in Chon Ju City were interviewed. The results of this study were as follow: 1. Frequency rate of menopausal symptoms was 38.4%. The most serious menopausal symptom was psychosomatic symptom. Mean score orders of experienced symptoms were back pain, joint pain (1.80), nervousness (1.80), general weakness (1.67). 2. The most important problems as perceived by the clients were children (45.8%), health (24.0%) and economics (7.8%). The most serious health problems were concerning the muscle-skeletal system (45%) such as arthritis, spinal disk problems and osteoporosis. Adult diseases (14.5%) such as hypertension and diabetes were also health concerns. Health management activities reported were exercise (22.5%), social activity (12%) and inactivity (53%). 33% of clients were interested in health groups and they wanted a program of health education, exercise and social activity to be provided. 3. General characteristic variables were significantly related to the level of menopausal symptoms as follows: age (t = -2.06, p = 0.040), status of marriage (t = -3.56, p = 0.000), educational level (F = 4.35, p = 0.05) and menopausal status (t = 4.37, p = 0.000).

Two human cases of Thelazia callipaeda infection in Korea

Thelazia callipaeda were observed from a 7-month old baby who lived in Uijongbu in 1989 and from a 42-year old man who lived in Anyang in 1994. These are the 23rd and 24th records of human thelaziasis in Korea as the literature are concerned.

Characterization of an upstream regulatory element of the human apolipoprotein E gene, and purification of its binding protein from the human placenta

We have previously demonstrated that expression of the human apolipoprotein (apo) E gene is controlled by multiple regulatory elements in the promoter [Paik et al. (1988) J. Biol. Chem. 263, 13340-13349; Chang et al. (1990) J. Biol. Chem. 265, 9496-9504]. To extend these studies, we have characterized an element in the apoE gene promoter that spans nucleotides -101 to -89, upstream regulatory element 3 (URE3). Transcription of promoter/marker gene constructs in vitro showed that URE3 modulates gene expression. Gel mobility shift assays of URE3 using human placental nuclear extracts detected a specific binding protein whose activity can be modulated by micromolar amounts of divalent copper and zinc. Competitive binding and gel shift assays with mutant oligonucleotides revealed critical nucleotides within URE3 required for its specific nuclear protein-binding activity. Gel filtration and oligonucleotide affinity chromatography were employed to isolate a URE3-binding protein (URE3BP) from human placental nuclear extracts. Purified URE3BP appears to be a M(r) = 300,000 protein that is composed of four equally-sized basic subunits of M(r) = 67,000. These studies indicate that URE3 is an active regulatory component of the apoE gene.

A case of giant hemangioma of the liver presenting with fever of unknown origin

A 37 year-old-woman was admitted to the hospital because of 15 days' duration of continuous fever. Routine studies for detection of fever foci were negative. Imaging studies revealed giant hemangioma of the liver with central thrombosis. The fever persisted for a period of 4 weeks, and subsided after conservative management. We report a case of hepatic hemangioma presenting with fever of unknown origin. The condition is very rare, but should be regarded as one of the causes of fever of unknown origin.

Development of thyroid autoimmunity after administration of recombinant human interferon-alpha 2b for chronic viral hepatitis

To investigate the frequency and clinical characteristics of autoantibody formation and development of autoimmune thyroid disease after interferon therapy, we measured the autoantibodies to thyrotropin receptor (TBII), thyroglobulin (ATA), and microsomal antigen (AMA) in 28 patients with histologically proven chronic viral hepatitis [25 males, three females; mean age 38.7 +/- 8.7 (SD) yr] receiving recombinant interferon-alpha 2b (IFN-alpha) treatment. Twenty patients with chronic hepatitis B (positive for HBsAg, HBeAg, and HBV DNA) and eight patients with chronic hepatitis C (positive for anti-HCV and HCV RNA) received IFN-alpha, 3 million units subcutaneously, three times a week for 6 months. Before, during, and up to 6 months after IFN-alpha therapy, thyroid hormone levels and titers of AMA, ATA, and TBII were measured every 2 months. None of them had thyroid dysfunction or antithyroid autoantibodies before IFN-alpha treatment. A 34-yr-old male patient developed Graves' disease during the last month of therapy. He required long-term antithyroid medications, even after discontinuation of IFN-alpha. Another 44-yr-old female patient developed AMA during IFN-alpha treatment; however, thyroid function remained normal and goiter did not develop in this patient. No other patient developed thyroid autoantibodies and thyroid dysfunction. In summary, only a small minority of patients will develop thyroid autoimmunity during IFN-alpha therapy, and much less often with this low dose of IFN-alpha.

The pathway responsible for EEG synchronization and effect of histamine on this system

Electrical stimulation (3 Hz, 0.5 volts) to the midbrain reticular formation of conscious rats induced significant increase of EEG power densities (synchronization) recorded at the frontal cortex (FCOR), nucleus ventralis thalami (VE), or nucleus medialis centralis thalami (CM). Significant synchronization was also observed in the FCOR when electrical stimulation was applied to the VE and CM. When ipsilateral and bilateral VEs were electrocoagulated, no EEG synchronization was observed in the FCOR and CM. Intracerebroventricular administration of histamine (Hi) caused a marked suppression of FCOR EEG synchronization in both CM-lesioned and normal rats through H1 receptors. EEG synchronization in FCOR was not induced in ipsilateral or bilateral VE-lesioned rats after RF stimulation. When Hi (1 microgram) was injected into the VE of normal rats, EEG synchronization of FCOR was markedly reduced after RF or VE stimulation. No such changes were induced when Hi was injected into the CM.