[Gentamicin-induced alteration in drug susceptibility and lipopolysaccharide-composition of Pseudomonas aeruginosa isolates]

Emergency of multi-drug resistance in Pseudomonas aeruginosa isolates after exposure to gentamicin was investigated with reference to their LPS-compositions. Three strains each of P. aeruginosa, different in LPS-compositions (long- and short-LPS strains, and LPS-deficient strain) were once or repeatedly incubated overnight at 35 degrees C in Mueller-Hinton broth including different concentrations of gentamicin, a poly-cationic antibiotic. LPS-compositions of the bacteria which survived and were grown after exposure to gentamicin were analyzed and the susceptibility to some of anti-pseudomonal drugs was determined. Of the test 9 strains after single exposure, No. 4 (long-LPS) and No. 41 (short-LPS) formed the LPS-deficient mutants. The resistance to ceftazidime and gentamicin was found in No. 4 strain, but not in No. 41 strain. Drug resistance in different patterns was also found in Nos. 43, 29, 45 and 52 strains without any change in their LPS-compositions. Contrary to these results, the susceptibility to norflxacin increased in Nos. 21 and 45 strains without any change in their LPS-compositions. After repeated exposures to gentamicin, the LPS-compositions of Nos. 4 and 14 (short-LPS) were altered and formed the LPS-deficient and the Intermediate-LPS (between short and long compositions) mutants, respectively. The LPS-alteration in both strains were accompanied by the development of resistance to ceftazidime and gentamicin, respectively. The drug resistance in different patterns were also found in Nos. 43, 156, 29, 41, 21, 45 and 52 strains, without any change in the LPS-compositions, whereas the increase in susceptibility to norfloxacin was simultaneously found in No. 45 strain. The ionic-binding of [3H]-gentamicin to the cell surfaces of two LPS-deficient mutants of P. aeruginosa decreased markedly, in comparison with that of the respective parents, and these results might lead to the drug resistance in the LPS-deficient mutants. However, the gentamicin-induced resistance of some strains of P. aeruginosa (but no change in the LPS-compositions) to the test drugs including gentamicin indicates a possibility that negative charges on the bacterial surface were decreased by the drug exposure. The drug resistance and LPS-compositions in the gentamicin-induced mutants of P. aeruginosa were stable during or after the 15th in vitro serial transfers.

Large sixth nerve neuroma involving the prepontine region: case report

OBJECTIVE AND IMPORTANCE

Tumors originating from the cranial nerves are uncommon, except for the acoustic and trigeminal neuromas. The sixth nerve, however, has the potential to generate neuromas with characteristic clinical features.

CLINICAL PRESENTATION

A 54-year-old woman presented with diplopia and increased intracranial pressure. Magnetic resonance imaging showed a large mass in the prepontine region. Surgery was performed via a condylar approach and demonstrated a tumor originating from the prepontine portion of the sixth nerve.

CONCLUSION

The sixth nerve neuroma at the pontomedullary junction showed characteristic clinical features and could be successfully removed via a condylar approach.

Early increase of gut intraepithelial mast cell precursors following Strongyloides venezuelensis infection in mice

The time-course of differentiation/proliferation of mast cells in gut epithelium was investigated in mice infected with the nematode Strongyloides venezuelensis. After infection, expression of proliferating cell nuclear antigen increased in gut intraepithelial mast cells on days 7 to 11, followed by an increase in the number of intraepithelial mast cells from days 11 to 14. Mast cell precursors were defined as cells that formed mast cell colonies in methylcellulose culture. After infection, the numbers of mast cell precursors in the population of gut intraepithelial mononuclear cells (IEMNC) increased significantly on day 3 and returned to the pre-infection level by day 7. Mast cell precursors in Peyer's patches, mesenteric lymph nodes (MLN), and spleen also increased from day 7 p.i. Production of IL-3 and IL-4 in MLN and spleen were increased between 7 and 11 days p.i. These results show that murine intestinal mastocytosis is initiated by an early increase in mast cell precursor number in the gut epithelium followed by proliferation/differentiation of mast cells. Mast cell precursor numbers increased even before the production of IL-3 and IL-4 in MLN and spleen, suggesting that some local factors might be involved in this phenomenon.

Early morphologic changes of atherosclerosis induced by ventromedial hypothalamic lesion in the spontaneously diabetic Goto-Kakizaki rat

It is generally thought that typical atherosclerotic lesions do not develop in the rodent. The Goto-Kakizaki (GK) rat is a nonobese strain in which a spontaneous type of non-insulin-dependent diabetes mellitus develops without apparent macroangiopathy. In our previous study, making ventromedial hypothalamic (VMH) lesions in GK rats induced hyperphagia and a further deterioration in glucose metabolism. In the current study, male GK rats in which VMH lesions were made were examined for vascular changes, with special reference to atherosclerotic lesions. Marked hyperglycemia in GK rats with VMH lesions (hereafter referred to as VMH lesion rats) was revealed over an observation period (plasma glucose levels 16 weeks after the operation: VMH lesion GK rats, 19.3 +/- 2.0 mmol/L, vs sham-operated GK rats, 10.1 +/- 1.3 mmol/L; p < 0.0001). Light microscopic observation of the descending aorta in VMH lesion GK rats 16 weeks after the surgery revealed that the intimal thickening and the number of infiltrating cells into the intima were significantly increased as compared with sham-operated GK rats (17531 +/- 3747 microm2 vs 3072 +/- 1192 microm2, p < 0.0001; 15.6 +/- 3.1 per one transverse section vs 6.8 +/- 2.5 per one transverse section, p < 0.0005). Electron microscopic observations demonstrated an increased number of microvilli and lysosomes in endothelial cells, infiltration of macrophages and lymphocytes into the intima, and migration of medial smooth muscle cells into the intima that are considered to be early events in atherosclerosis. These morphologic changes could be induced by a deterioration in glucose metabolism. This rat may thus be useful for studying the process of the initiation of atherosclerosis in diabetes mellitus.

The presence of a manganese-rich particle in lysosome of rat pancreas due to excess manganese treatment

Manganese (Mn) accumulates at a higher level in the pancreas than in any other organs when excess Mn is administered to the rat. The present study is carried out to analyze the intracellular localization of Mn existed in the pancreatic cell of Mn-treated rats. Transmission electron microscope and X-ray micro-analysis connected with a rapid freezing fixation technique showed that a large amount of Mn was localized in lysosomal particles of the pancreatic cell of Mn-treated rats. The Mn-rich particles disappeared when the element-administration was discontinued, showing that the accumulation of Mn is reversible. To confirm that Mn is in the lysosomes, a centrifugal subcellular-fractionation and a neutron activation analysis were carried out. The result indicated that much Mn existed in the lysosomal fraction.

Visceral fat accumulation as an important risk factor for obstructive sleep apnoea syndrome in obese subjects

OBJECTIVES

It is well known that obstructive sleep apnoea-(OSA) is frequently associated with obesity. In the current study, we investigated the correlation between abdominal visceral fat accumulation and the presence of OSA in obese subjects.

SUBJECTS

A consecutive series of 37 patients (17 men and 20 women) with primary obesity who were admitted to the Second Department of Internal Medicine. Osaka University Hospital, were investigated Patients with OSA were designated as those whose apnoea index (number of apnoea h-1 of sleep) was more than 5.

MAIN OUTCOME MEASURES

The distribution of body fat was determined using computed tomographic sections. The upper airway dimensions were evaluated with indices obtained by cephalometry in both inspiratory and expiratory phases.

RESULTS

Visceral adipose tissue (AT) area which was measured at the level of the umbilicus, and its ratio to total AT area were both significantly greater in OSA patients as compared with those in non-OSA patients. All subjects whose visceral AT area measured more than 220 cm2 manifested OSA. These two parameters also closely correlated with an increase in apnoea index. A multiple linear regression analysis revealed that the visceral AT area significantly correlated to apnoea index when age, AT mass and lean body mass were taken into account. The fluctuations of the upper airway were significantly greater in the large visceral fat group than in the small visceral fat group.

CONCLUSIONS

These results suggest that visceral fat accumulation is an important risk indicator for OSA in obese subjects.

Effects of swimming training on brown-adipose-tissue activity in obese ob/ob mice: GDP binding and UCP m-RNA expression

Brown adipose tissue (BAT) of obese animals is generally in a relatively atrophied and thermogenically quiescent state. The aim of the current study was to investigate the effect of swimming training on BAT activity in lean and obese (ob/ob) mice. The trained mice underwent a 6-week endurance swimming training (1 h/day, 5 days/week) in water at 35-36 degrees C. The swimming training significantly increased BAT mass and its protein content in both the lean and obese mice, suggesting hypertrophy. After swimming training, the amounts of protein and guanosine 5'-diphosphate binding in the mitochondria recovered from BAT of both mice increased significantly as compared with the respective sedentary groups, whereas the uncoupling protein (UCP) content increased significantly only in lean mice. After swimming training, the level of UCP mRNA expression did not change substantially in lean mice but appeared to increase in obese mice. The results obtained here suggest that swimming training leads to an increase in the nonshivering thermogenesis of obese mice in addition to lean mice.

Inactivation of p16/CDKN2 and p15/MTS2 genes in different histological types and clinical stages of primary ovarian tumors

To define the involvement of p16/CDKN2 and p15/MTS2 inactivation in ovarian tumorigenesis and the association of these inactivation events with histological types and clinical stages of ovarian tumors, we analyzed homozygous deletion and somatic mutation of p16/CDKN2 and p15/MTS2 genes, as well as hypermethylation of the 5'-CpG island of the p16/CDKN2 gene, in 49 primary ovarian tumors and 6 ovarian carcinoma cell lines. We found homozygous deletions of p16/CDKN2 and p15/MTS2 in 6 (12%) and 5 (10%) primary tumors, respectively. Somatic mutation of p16/CDKN2 was found in only 1 primary tumor, but mutation of p15/MTS2 was not detected in any sample. None of the 28 primary tumors or 6 cell lines was hypermethylated at the 5'-CpG island of p16/CDKN2. The incidence of inactivation of p16/CDKN2 in primary tumors was significantly higher in the advanced stages (7 of 29) than in the early stages (0 of 14). Seven of 9 alterations in p16/CDKN2 and p15/MTS2 were observed in serous (3 of 12), endometrioid (3 of 9) and clear-cell (1 of 4) carcinomas. However, only normal sequences of these genes were detected in mucinous carcinomas. Loss of heterozygosity (LOH) at the IFNA locus was detected in 1 of 19 (5%) tumors, but no change at the D9S171 locus was observed in 17 tumors. These results suggest that: (i) homozygous deletion is the main mechanism of inactivation of p16/CDKN2 and p15/MTS2 in ovarian tumorigenesis; (ii) inactivation of p16/CDKN2 and p15/MTS2 may be the histological type-specific events involved in ovarian tumorigenesis; and (iii) inactivation of p16/CDKN2 is potentially involved in the progression of ovarian tumors in advanced stages.

Localization of heparin-binding epidermal growth factor-like growth factor in human coronary arteries. Possible roles of HB-EGF in the formation of coronary atherosclerosis

BACKGROUND

Heparin-binding epidermal growth factor (EGF)-like growth factor (HB-EGF) is a newly identified member of the EGF family. Our previous in vitro studies showed that HB-EGF is a potent mitogen and chemoattractant for vascular smooth muscle cells (SMCs), suggesting the role of HB-EGF in the pathogenesis of atherosclerosis. The purposes of the present study were to investigate the localization of HB-EGF in both normal and atherosclerotic human coronary arteries and to elucidate the possible roles of this growth factor in the formation of atherosclerotic lesions.

METHODS AND RESULTS

The immunohistochemical localization of HB-EGF, SMCs, macrophages, and EGF receptors (EGFRs) was examined in human coronary arteries obtained at autopsy. The medial SMCs of coronary arteries in neonates, infants, and children consistently synthesized HB-EGF protein. In normal adults, however, the relative number of HB-EGF-positive medial SMCs decreased gradually with age after about 30 years of age. In nonatherosclerotic coronary arteries with diffuse intimal thickening, SMCs of the intima, especially those located in the area of the medial side of the intima, were strongly positive for HB-EGF protein. In atherosclerotic plaques of coronary arteries with eccentric intimal thickening, both SMCs and macrophages in and around the core lesions, in addition to the intimal and medial SMCs located adjacent to the plaque, produced HB-EGF protein. A strong immunostaining of EGFRs was observed in these SMCs, suggesting a close association of HB-EGF and EGFR expression.

CONCLUSIONS

These data suggest that HB-EGF might play important roles in the migration of SMCs from the media to the intima, the proliferation of intimal SMCs, and the interaction between SMCs and macrophages in the process of coronary atherogenesis.

[A case of Sparganosis mansoni with a painless mass in the inguinal region and the scrotum]

Sparganosis mansoni rarely occurs in the inguinal and perineal regions in Japan. A case of Sparganosis mansoni with a painless mass in the left inguinal region is presented. A 67-year-old male visited our hospital with a complaint of a painless mass in the left inguinal region in May, 1995, and another mass appeared in the scrotum two days after the first visit. Ultrasonography revealed a solid subcutaneous mass 2 cm in diameter. These masses were surgically excised by an inguinal approach and a parasite, 10 cm in length, was found in the mass. The parasite was diagnosed histologically as Sparganosis mansoni, which is a larva of the genus Diphyllobothrium.

Preparation of anti-human thymidine phosphorylase monoclonal antibodies useful for detecting the enzyme levels in tumor tissues

The antitumor activity of cytostatic 5'-deoxy-5-fluorouridine (5'-dFUrd) depends on its being converted to 5-fluorouracil (5-FUra) by the enzyme thymidine phosphorylase (dThdPase, EC 2.42.4). We prepared mouse anti-human dThdPase monoclonal antibodies to serve as tools for clinical studies with this drug. Partially purified dThdPase obtained form HCT116 human colon cancer cells grown in athymic mice was used as and antigen for the immunization of mice. Six hybridomas were cloned which produced anti-human dThdPase antibodies, as detected by Western blot analysis with human dThdPase. With these antibodies, we developed an ELISA method sensitive enough to measure dThdPase levels, even in tumor tissue samples weighing as little as 10 mg. In addition, one monoclonal antibody was suitable for immunologically staining the enzyme in tumor tissues. Thus, these anti-human dThdPase monoclonal antibodies could be used to measure levels of the enzyme in tumor cells, which is essential for the activation of 5'-dFUrd.

[A case of poorly differentiated ovarian serous adenocarcinoma responding favorably to etoposide and cisplatin]

A case of primary ovarian cancer responding favorably to EP therapy is reported. The patient is a 41-year-old woman with stage IV poorly differentiated serous papillary adenocarcinoma of the ovary. At 21 days after the optimal initial surgical exploration, multiple tumor nodules recurred in peritoneal cavity, and one of them had a diameter of 5 cm. Since we had found previously that poorly differentiated adenocarcinoma of the ovary responded to etoposide by a disease-oriented screening system, the patient was treated by combination chemotherapy (etoposide 100 mg/body/day x 5 days + cisplatin 20 mg/body/day x 5 days) as first line chemotherapy. After 2 cycles of chemotherapy, the tumor disappeared on CT, and the serum CA 125 level decreased to 14 U/ml from 2,050 U/ml. She was evaluated as a complete response after 5 cycles of combination chemotherapy, and only mild side-effects were recognized. These results demonstrate that the combination chemotherapy of etoposide and cisplatin might be recommended as first-line chemotherapy for poorly differentiated serous adenocarcinoma of the ovary.

Gene rearrangements in snake mitochondrial genomes: highly concerted evolution of control-region-like sequences duplicated and inserted into a tRNA gene cluster

Mitochondrial DNA (mtDNA) regions corresponding to two major tRNA gene clusters were amplified and sequenced for the Japanese pit viper, himehabu. In one of these clusters, which in most vertebrates characterized to date contains three tightly connected genes for tRNA(Ile), and tRNA(Gln), and tRNA(Met), a sequence of approximately 1.3 kb was found to be inserted between the genes for tRNA(Ile) and tRNA(Gln). The insert consists of a control-region-like sequence possessing some conserved sequence blocks, and short flanking sequences which may be folded into tRNA(Pro), tRNA(Phe), and tRNA(Leu) genes. Several other snakes belonging to different families were also found to possess a control-region-like sequence and tRNA(Leu) gene between the tRNA(Ile)and tRNA(Gln) genes. We also sequenced a region surrounded by genes for cytochrome b and 12S rRNA, where the control region and genes for tRNA(Pro) and tRNA(Phe) are normally located in the mtDNAs of most vertebrates. In this region of three examined snakes, a control-region-like sequence exists that is almost completely identical to the one found between the tRNA(Ile) and tRNA(Gln) genes. The mtDNAs of these snakes thus possess two nearly identical control-region-like sequences which are otherwise divergent to a large extent between the species. These results suggest that the duplicate state of the control-region-like sequences has long persisted in snake mtDNAs, possibly since the original insertion of the control-region-like sequence and tRNA(Leu) gene into the tRNA gene cluster, which occurred in the early stage of the divergence of snakes. It is also suggested that the duplicated control-region-like sequences at two distant locations of mtDNA have evolved concertedly by a mechanism such as frequent gene conversion. The secondary structures of the determined tRNA genes point to the operation of simplification pressure on the T psi C arm of snake mitochondrial tRNAs.

Visceral fat accumulation and vascular complications associated with VMH lesioning of spontaneously non-insulin-dependent diabetic GK rat

OBJECTIVE

We have reported that ventromedial hypothalamic (VMH) lesions induced marked hyperglycemia and a distinct reduction in pancreatic insulin content during short-term observation in male Goto-Kakizaki (GK) rats, an animal model for non-insulin-dependent diabetes mellitus (NIDDM) (Metabolism 43: 32-37, 1994). We investigated the long-term effect of VMH lesions on glucose metabolism, pancreatic insulin content, abdominal fat distribution and vascular complications in male GK rats.

DESIGN

Metabolic and histological examinations in male GK rats during 16 weeks after making VMH lesions were compared to those in sham operated GK or Wistar rats.

SUBJECTS

Eleven 9-week-old male GK rats and 4 male Wistar rats. VMH-lesions were made in 6 GK rats and sham operation were performed on 5 GK rats and 4 Wistar rats as controls.

MEASUREMENTS

Food intake, body weight, and plasma glucose, insulin and lipid levels at 2 weeks interval after operation. Urinary protein and albumin levels at 15 weeks after operation. Measurement of pancreatic insulin content, mesenteric fat and abdominal subcutaneous fat weights, and histological examinations of kidney and aorta were performed after 16 weeks.

RESULTS

Although food intake increased in VMH-lesioned GK (GK-VMH) rats compared with that in sham-operated GK (GK-sham) rats, the body weight of GK-VMH rats was significantly less than that of GK-sham rats. Plasma glucose was markedly elevated in GK-VMH rats from 2 through 16 weeks after operation, while it was only mildly increased in GK-sham rats. Plasma insulin levels were higher in GK-VMH rats one week after operation and thereafter tended to be lower compared to those in GK-sham rats. Plasma triglyceride levels were significantly increased in GK-VMH rats. The insulin content of pancreas at 16 weeks after operation was markedly decreased in GK-VMH rats. VMH lesions caused a significant 1.2-fold increase in mesenteric fat weight and a 1.3-fold higher ratio of mesenteric fat weight to subcutaneous fat weight in GK rats compared with sham-operated rats at 16 weeks after operation. The urinary excretions of protein and albumin in GK-VMH rats were greater than those in GK-sham rats. Histological examinations of the kidneys in GK-VMH rats revealed that the glomerular basement membranes were thicker than those of GK-sham rats. The descending aorta in GK-VMH rats also showed morphologic changes in the intima characteristic of an early stage of atherosclerosis.

CONCLUSION

Male GK-VMH rats may be a useful animal model for non-obese NIDDM with visceral fat accumulation, which develops typical diabetic complications, including both microangiopathy and macroangiopathy.

Lung granulomatous response induced by infection with the intestinal nematode Nippostrongylus brasiliensis is suppressed in mast cell-deficient Ws/Ws rats

Certain nematode infections induce eosinophil infiltration and granulomatous responses in the lungs. To examine the role of mast cells in the development of lung lesions, normal +/+ and genetically mast cell-deficient Ws/Ws rats were infected with the nematode Nippostrongylus brasiliensis. In +/+ rats, numbers of eosinophils in bronchoalveolar lavage fluid (BALF) increased significantly 3-7 days after infection, and granulomatous responses composed of histiocytes/ macrophages and multinucleate giant cells were triggered in the lungs 3-14 days after infection. Challenge infection, which was carried out on day 28 after primary infection, induced much higher levels of granulomatous response than after primary infection, suggesting that the response is mediated at least in part by an immunological mechanism. In Ws/Ws rats, both the eosinophil percentage in BALF and the size of the granulomas in the lungs were significantly smaller than in +/+ rats after primary as well as after challenge infection. The amount of rat mast cell protease (RMCP) II in +/+ rat BALF was increased 1 day after primary infection and more significantly after challenge infection, suggesting that lung mucosal mast cells were activated more markedly after the challenge infection. In Ws/Ws rats, RMCP II was undetectable throughout the observation period. The time course of nematode migration in the lungs did not differ in +/+ and Ws/Ws rats. These results suggest that mast cell activation might be relevant to eosinophil infiltration and granulomatous response in the lungs, although the responses do not affect lung migration of the nematode.

Mutation analysis of gonadotropin receptor and G protein genes in various types of human ovarian tumors

The heterotrimeric guanine-nucleotide-binding proteins (G proteins) and G protein-coupled hormone receptors including gonadotropin receptors have been suggested to play a role in ovarian tumorigenesis. However, no functional significance of gonadotropin receptors and G proteins in this process has been demonstrated. To investigate this issue, we examined point mutations in these genes in various types of ovarian tumors by polymerase chain reaction-single strand conformation polymorphism analysis and direct sequencing. Among 37 tumors (20 epitherial, 8 sex cord-stromal, and 9 germ cell tumors) and 5 carcinoma cell lines examined, no mutational sequence of G protein-interaction domains of luteinizing hormone receptor and follicle-stimulating hormone receptor, or "hot spots" of the alpha subunit of adenylyl cyclase-stimulating G protein and -inhibitory G protein was observed. Although this analysis was performed on only a limited number of tumors and cell lines, and on limited gene loci, the results suggest that mutational activation in gonadotropin receptors and G proteins is not crucial for ovarian tumorigenesis.

Alpha 1-adrenergic stimulation induces cardiac tolerance to hypoxia via induction and activation of Mn-SOD

We examined whether or not alpha 1-adrenergic stimulation increases the tolerance of the heart to ischemia using a hypoxia-reoxygenation model of cardiac myocytes. After exposure to norepinephrine (NE; 0.2 microM) for 24 h, the manganese superoxide dismutase (Mn-SOD) content and activity in the cells were increased from 0.61 +/- 0.03 to 0.87 +/- 0.04 microgram/dish and 22 +/- 1 to 55 +/- 4 U/dish, respectively. The specific activity of Mn-SOD was also increased from 36 to 63 U/microgram Mn-SOD protein after the stimulation with NE. Prazosin (2 microM) abolished the increase in Mn-SOD activity (U/mg total protein). Creatine kinase (CK) release after hypoxia (PO2 7 mmHg; 3 h)-reoxygenation (1 h) from cells pretreated with NE in the presence of propranolol and yohimbine for 24 h was attenuated by 48% compared with that from cells without NE stimulation. When antisense oligodeoxyribonucleotides to Mn-SOD were added to myocyte cultures, the increase in Mn-SOD activity (U/mg total protein) and the attenuation of CK release after the addition of NE in the presence of propranolol and yohimbine were not observed. These results suggest that alpha 1-adrenergic stimulation increases the tolerance of myocytes to hypoxia through induction and activation of Mn-SOD.

[Incidence of synchronous or metachronous multiple primary cancers and aggregation of cancers in families of patients with endometrial cancer]

We evaluated the incidence of synchronous or metachronous multiple primary cancer, hereditary or familial cancer, and the familial aggregation of cancer in 142 patients who were treated for endometrial cancer at Tsukuba University Hospital in the period 1977 to 1995. Synchronous multiple primary cancers were identified in 6 of the 142 patients (4.2%). Eleven patients (7.7%) had a history of extraendometrial cancer. Patients with endometrial cancer had a significantly high incidence of a history of breast cancer. Endometrial cancer was diagnosed in two patients who were screened before menopause. Four patients with endometrial cancer (2.8%) subsequently developed extraendometrial forms of cancer. One patient (0.7%) was considered to have a hereditary form of cancer, and 5 patients (3.5%) had familial forms of cancer. A total of 86 cases of cancer were found among 53 kindred (37.3%). More detailed studies are needed to elucidate the aggregation of cancers in the families of patients with endometrial cancer in Japan. Patients with a history of breast cancer should be screened for the presence of endometrial cancer.

Heme oxygenase-1 expression and its relation to oxidative stress during primary culture of cardiomyocytes

The inducible form of heme oxygenase (heme oxygenase-1) is a heat shock protein 32 (HSP32) whose expression is induced by numerous agents, including heme compounds and heavy metals, and during oxidative stress. The purpose of this study was to examine whether heme oxygenase-1 is induced during primary cell culture of cardiomyocytes and the relation of heme oxygenase-1 expression to oxidative stress levels. Western blot analysis and reverse transcription-polymerase chain reaction analysis showed heme oxygenase-1 expression 12-48 h after isolation of rat neonatal cardiomyocyte for culture. Its expression was barely detected immediately after isolation. Actinomycin D or cycloheximide completely suppressed such expression. Myocardial cells were exposed to oxidative stress during the first 12 h after isolation as assessed by their glutathione redox state; the ratio of reduced glutathione/oxidized glutathione was less than 10. The expression of heme oxygenase-1 was significantly reduced by treatment with reduced glutathione (58% reduction, P < 0.05), but markedly increased by treatment with hydrogen peroxide (65% increase, P < 0.05) 12 h after isolation. Expression of heat shock protein 70 was not significantly changed during primary culture incubation. Results indicate that heme oxygenase-1 is expressed during primary culture of cardiomyocytes. Its expression is closely related to the oxidative stress level of the cultured cells.

[Effects of intra-hepatic arterial injection of mitoxantrone for hepatocellular carcinoma]

Twenty patients with unresectable hepatoma, recurrent hepatoma or metastatic liver cancer were treated by intra-hepatic arterial injection of mitoxantrone, and its effectiveness and side effects were studied. In 35.5% of the patients, complete or partial responses were seen. The survival intervals after the beginning of therapy were from one to 21 months (mean, 9.4 months) and one-year survival ratio was 56.3%. Red blood cell, leukocyte, and platelet counts diminished significantly one week later after administration of mitoxantrone compared with the pre-administration levels. Severe hepatic dysfunction has not been experienced.