Processing of E1 and E2 glycoproteins of hepatitis C virus expressed in mammalian and insect cells

Processing of the envelope glycoproteins (E1 and E2) of hepatitis C virus (HCV) was investigated by using cDNA clones covering the structural and part of the nonstructural (NS) protein regions. The cDNA clones expressed in mammalian and insect cells were immunoprecipitated by serum of a hepatitis C patient and by monoclonal and polyclonal antibodies raised against the recombinant proteins expressed in insect cells or Escherichia coli. The E2 protein expressed in both insect and mammalian cells was a glycoprotein of 60 kDa (gp60) and removal of the sugar residues by N-glycanase yielded 38- and 40-kDa proteins. Pulse-chase experiments revealed that efficient expression and processing of the envelope proteins required coexpression with the flanking core and NS2 proteins. Not only E1 and E2 proteins but also NS2 and NS3 proteins were coprecipitated by anti-E1 or anti-E2 monoclonal antibody in the cells infected with the recombinant baculovirus expressing structural and NS proteins (NS2 and NS3), while only the NS3 protein was precipitated by anti-NS3 antibody. The association of E1 and E2 proteins was not influenced by the presence of a reducing agent and was still observed in the cells coinfected with the deletion mutants lacking both internal and C-terminal hydrophobic regions of each protein. Furthermore, the truncated forms of the E1 and E2 proteins were secreted into the culture supernatant and some of them were still associated with each other.

Effects of prolonged administration of perfluorooctanoic acid on hepatic activities of enzymes which detoxify peroxide and xenobiotic in the rat

Male and female rats were fed a diet containing 0.01% (w/w) perfluorooctanoic acid (PFOA) for 2 or 26 weeks, and the effects on enzymes that participate in the metabolism of peroxides and xenobiotics in liver were studied. Elevated activity of peroxisomal beta-oxidation persisted throughout the treatment of male rats with PFOA for 26 weeks. The activity of glutathione (GSH) peroxidase towards hydrogen peroxide was depressed significantly by the prolonged administration. The long-term treatment of male rats with PFOA decreased the activity of GSH peroxidase towards cumene hydroperoxide and increased the activity of microsomal NADPH-dependent lipid peroxidation. The activities of GSH reductase and hepatic content of GSH remained unchanged. There was no difference in the content of conjugated dienes in microsomal lipid between male rats exposed to PFOA for 26 weeks and age-matched control. The activities of GSH S-transferase towards 1-chloro-2,4-dinitrobenzene and 1,2-dichloro-4-nitrobenzene were depressed by the short-term administration of PFOA to male rats, and this inhibition became pronounced during the prolonged treatment. Microsomal cytochrome P450 was induced by the short-term treatment of male rats with PFOA, and elevated levels persisted throughout the treatment for 26 weeks. Upon the administration of PFOA to male rats for 2 weeks, the activity of 7-ethoxycoumarin O-deethylase was increased markedly, whereas the activities of either aniline p-hydroxylase or aminopyrine N-demethylase were unchanged. Although an age-dependent decrease was observed in the activity of 7-ethoxycoumarin O-deethylase, the activity in male rats treated with PFOA for 26 weeks was higher than that of age-matched control, to the same extent as was observed with the short-term treatment. The prolonged administration of PFOA to male rats caused a significant increase in the activity of both aniline p-hydroxylase and aminopyrine N-demethylase. Little changes were found in the same parameters tested in female rats even after the prolonged administration of PFOA.

Use of the sandwich method with an ultra-high-molecular-weight polyethylene prosthesis and Marlex mesh in sternal reconstruction: report of a case

A 52-year-old Japanese man with a slow-growing chondroma originating from the sternal bone was referred to our hospital. A subtotal resection of the sternum was performed, hereafter termed the "sandwich method," and an originally designed prosthesis made from ultra-high-molecular-weight polyethylene and Marlex mesh was used for reconstruction. The postoperative course was uneventful without any symptoms due to paradoxical movement of the chest or regional abscess, and no disturbance in the movement of the upper limbs, such as a surgical sequelae, was observed.

Raloxifene preserves bone strength and bone mass in ovariectomized rats

We investigated the effects of raloxifene, a nonsteroidal benzothiophene, on bone strength in ovariectomized rats and compared them with estrogen treatment. Sixty ovariectomized Sprague-Dawley rats were divided into three groups for treatment with orally dosed raloxifene (3 mg/kg), ethynyl estradiol (EE, 0.1 mg/kg), or vehicle. A fourth group of 20 rats that underwent sham ovariectomies and received vehicle was used for comparison. Treatments began 3 days after ovariectomy and continued for 6 months. Raloxifene treatment resulted in greater bone strength in the lumbar vertebrae (P < 0.05) and femoral neck (P < 0.01) and greater bone mineral density at the proximal tibia (P < 0.001) and lumbar vertebrae (P < 0.001) when compared with vehicle-treated ovariectomized animals. The positive effects on bone biomechanical properties from raloxifene treatment were not different than those associated with EE treatment. Raloxifene did not cause a significant increase in uterine weight, whereas EE treatment resulted in uterine weight increased 4-fold over vehicle-treated ovariectomized controls. Therefore, in rats, raloxifene has beneficial effects on bone biomechanics that are equivalent to those of EE treatment without substantial effects on the uterus.

Retinal complications with elevated circulating plasma C5a associated with interferon-alpha therapy for chronic active hepatitis C

Retinal hemorrhage is a complication of interferon therapy of unknown pathogenesis. We report two chronic active hepatitis C patients who developed retinal hemorrhage and/or cotton wool patches during interferon-alpha therapy 4 and 12 wk after beginning treatment. At the time of the hemorrhage, plasma-activated complement 5, a known potent intravascular aggregator of granulocytes, increased to 54 ng/ml in one patient and to 29 ng/ml in the other patient. When the hemorrhage resolved, it decreased to under 5 ng/ml. Our cases suggest that complement activation occurs in patients treated with interferon-alpha and that activation of complement 5 can lead to retinal capillary infarction and retinal hemorrhage. High levels of activated complement 5 may predict retinal artery infarction or perhaps microvascular emboli in the other organs.

[Significance of surgical treatment for bone metastasis from lung cancer]

To assess significance of surgical therapy for patients who had metastatic bone tumor from primary lung cancer, sites of recurrence in patients who underwent surgical resection for lung cancer lesions were analyzed. Clinical courses of patients who underwent surgical therapy for metastatic bone tumor were analyzed, too. 1) From 1985 to 1989, 88 patients died from lung cancer in our hospital who has underwent pulmonary resection for lung cancer lesions. Of these, 22 patients had metastatic bone tumor. Sixty patients died who had underwent complete resection for lung cancer lesions. In eight patients of these 60 cases, bone were first site of recurrence. Of these eight patients, length from pulmonary resection to detection of bone metastasis were 4-23 months. In the other hand, length from detection of bone metastasis of death were 3-24 months. There was no correlation between two length. All of these eight patients had another metastatic lesions at the time of death. 2) From 1985 to July 1993, twelve patients underwent surgical therapy for their bone metastasis of primary lung cancer. Of these, four had metastatic cancer in thoracic vertebral body, two had in clavicle, two had in rib, three had in femoral bone, another had in tibial bone. Objective of operation were improvement of paralysis or pain, prevention of fracture, and so on. Most cases succeeded to get improvement in a short time, but some cases got worse soon. Surgical treatment was effective to improve paralysis or pain, and to increase quality of life. But it can not be effective except appropriate management in a short time because another symptom raise soon.

Magnetic resonance imaging of subacute thyroiditis

Clinical, laboratory, and scintigraphic findings, and magnetic resonance (MR) images of three patients with subacute thyroiditis are presented in all three at the time of diagnosis. On T1-weighted images, regions of abnormality with irregular margins and slightly high intensity were demonstrated. On T2-weighted images, markedly increased intensity was shown in the same sites. On follow-up MRI in two patients after treatment, these findings had disappeared or become more normal.

Flavanones with potent antibacterial activity against methicillin-resistant Staphylococcus aureus

With the therapeutic concept of using the defensive ability of plants against microbial infections, phytoalexin, an antimicrobial phytochemical was studied for its ability to inhibit the growth of methicillin-resistant Staphylococcus aureus (MRSA). Extracts from Sophora exigua (Leguminosae) were fractionated by serial chromatography and the anti-MRSA activity of each fraction was determined by the agar-plate method. Among the active isolates, 5,7,2',6'-tetrahydroxy-6-isoprenyl-8-lavandulyl-4'-methox yflavanone (exiguaflavanone D) completely inhibited the growth of all the MRSA strains examined at the concentration of 1.56-6.25 micrograms mL-1, and 5, 2',6'-trihydroxy-8-lavandulyl-7-methoxy-flavanone (exiguaflavanone B) inhibited at a concentration of 50 micrograms mL-1. This former compound is expected to be a phytotherapeutic agent for MRSA infections as an alternative to conventional antibiotics with unwanted side-effects or the appearance of antibiotic-resistant bacteria.

Response of cytosolic Ca2+ to hypercapnic acidosis in cultured glomus cells of the adult rabbit carotid body

The characteristics underlying the response of cytosolic Ca2+ ([Ca2+]i) to hypercapnic acidosis in clusters of cultured glomus cells of the adult rabbit carotid body were evaluated using fura-2 microscopic fluorometry. Application of CO2 by bubbling through both superfusions of bicarbonate-buffered saline and HEPES-buffered saline produced a rapid and sustained increase in [Ca2+]i. The [Ca2+]i response increased correspondingly with a rise in concentrations of CO2 to 20% but at a point between 20 and 50% adapted to CO2 and it decreased its linear assent. The hypercapnic acidosis-induced increase of [Ca2+]i was diminished by removing external Ca2+. Also the [Ca2]i response was reduced in dose-dependent fashion by the addition of the voltage-gated Ca2+ channel blocker D600. An additional response of [Ca2+]i to acetate was also diminished by Ca2+ removal. These results suggest that the [Ca2+]i response to hypercapnic acidosis involves an influx of external Ca2+ through voltage-gated Ca2+ channels.

Tumor doubling time and prognostic assessment of patients with primary lung cancer

BACKGROUND

Relationships between tumor doubling time (DT) and other prognostic factors and the risk of death related to these factors are not yet fully understood.

METHODS

Tumor doubling time of primary lung carcinomas of 174 patients, detected in a limited number of local municipalities during a limited period, was calculated using the Schwartz formula. Survival rate of the 174 patients was compared with reference to categories of prognostic factors (univariate analyses) and significant factors affecting survival were identified by multivariate analyses using the Cox proportional hazard model.

RESULTS

Tumor doubling time had a log normal distribution. There was a significant difference in mean DT in relation to sex, smoking history, presence of symptoms, cell type, primary tumor factor, and stage. Univariate analyses showed a significant difference in survival in relation to DT, age, sex, method of tumor detection, smoking history, symptoms, therapy, cell type, primary tumor (T) factor, regional lymph node (N) factor, distant metastasis (M) factor, and stage. Multivariate analyses using the Cox's proportional hazard model in a stepwise fashion identified a final set of five significant variables: N factor (P = 0.0001); therapy (P = 0.0016); M factor (P = 0.0017); T factor (P = 0.0018), and DT (P = 0.0152).

CONCLUSIONS

Tumor doubling time was an independent and significant prognostic factor for lung cancer patients.

Carbohydrate-mediated recognition of a circulating placental alkaline phosphatase-immunoglobulin M complex

We detected an abnormal alkaline phosphatase (AP) electrophoretically in the serum of a patient with rheumatoid arthritis, who had a macromolecular AP linked with immunoglobulin M (IgM) bearing a kappa light chain. The IgM isolated from the AP-IgM complex in the patient's serum reacted apparently with all of the AP isozymes tested, i.e. those originating in the liver, bone, intestine and placenta, but the alpha-mannosidase-treated IgM from the patient's serum bound to placental AP (PAP) alone. This suggests that untreated IgM recognizes multivalent epitopes of the AP and that the complex of AP with alpha-mannosidase-treated IgM is a specific antibody-antigen complex. In order to investigate further the multivalent binding capacity for the PAP-untreated IgM complex, we prepared a monoclonal antibody (MoAb) against PAP and identified it as an IgM with a kappa light chain. The binding affinities and their circulating half-lives of the synthetic complexes of PAP and respective MoAbs were examined with and without treatment with several glycosidases. The untreated MoAb bearing IgM had binding affinity for all of the AP isozymes tested, while alpha-mannosidase-treated IgM attached only to PAP, the same as the IgM isolated from the PAP-IgM complex in the patient's serum. The circulating clearance of the PAP-IgM complex in rabbits was faster than either component alone. In addition, the PAP-IgM complex treated with alpha-mannosidase was found to have the shortest half-life of all the complexes of PAP and Igs treated with the several glycosidases tested. These results suggest that the formation of the PAP-IgM complex as an enzyme-linked antibody and the clearance of the complex in vivo are dependent on the sugar moieties of the Igs.

[A case of mitral valve replacement with chronic idiopathic thrombocytopenic purpura after high-dose immunoglobulin infusion]

A 60-year-old female patient diagnosed as having mitral stenosis with chronic idiopathic thrombocytopenic purpura (ITP), with a platelet count of 6.8 x 10(4)/mm3, was scheduled to undergo mitral valve replacement. High-dose immunoglobulin infusion (400 mg/kg/day for five days) was begun four days before the operation and increased the platelet count to 9.1 x 10(4)/mm3 just before the operation. Intraoperative hemostasis was excellent, and the postoperative course was uneventful. High-dose immunoglobulin therapy appears to be a first choice for controlling hemorrhagic tendency in ITP patients undergoing heart surgery.

Relationship between thyroid functions and urinary growth hormone secretion in patients with hyper- and hypothyroidism

Thyroid hormone plays an important role in growth hormone (GH) synthesis and secretion. To study the relationship between thyroid function and urinary GH secretion in the hyperthyroid and hypothyroid states, we measured thyroid hormones, simultaneously with serum and urinary GH levels, in 54 patients with thyroid diseases. GH-releasing hormone (GRH) test was performed in 18 patients in order to evaluate serum and urinary GH responses to GRH in hyper- and hypothyroid states. Serum thyroid hormone levels were strongly correlated with the urinary GH levels in the patients, and the correlation was greater than that between serum thyroid hormone and serum GH levels. Urinary GH levels were significantly higher in the hyperthyroid patients than in the euthyroid and hypothyroid patients, although serum GH levels were not significantly different among these three groups. Serum GH response to GRH was significantly decreased in hyperthyroid patients as compared to euthyroid patients. However, urinary GH levels after GRH administration were not decreased in the hyperthyroid patients. These results suggest that hyperthyroid states increase GH in urine and may accelerate the urinary clearance of GH.

Anti-Candida activity of synthetic hydroxychalcones

The antifungal activity of different synthetic hydroxychalcones was determined against Candida species. It was revealed that the presence of hydroxyl groups at C-2, C-4, and C-2' in chalcone was essential to inhibit Candida growth. Among the chalcone derivatives examined, 2,4,2'-trihydroxy-5'-methylchalcone showed the most intensive anti-Candida activity, suggesting that it could be a potential therapeutic agent for candidosis.

Morphogenesis of normal human salivary gland cells in vitro

Primary cultured human salivary gland cells were transfected with ori-defective mutant DNA of SV40. Following 2-3 weeks of transfection, slowly expanding colonies consisting of small compact cells emerged, while mock-transfected cells did not grow any more and eventually entered crisis, followed by cell death. Using limited dilution technique, we isolated 4 cell clones with distinct morphology from a single colony. Morphological observation of cells cultured on plastic dishes precisely revealed the characteristics of the constituent cells of salivary gland; i.e., three cell clones showing cuboidal- (NS-SV-DC), spindle- (NS-SV-MC), and flattened morphology (NS-SV-SC) were similar to duct-, myoepithelial-, and squamous phenotype, respectively. A remaining cell clone, polygonal in shape and with numerous secretory granules (NS-SV-AC), resembled an acinar cell. Characterization of cell clones by ultrastructural examination and search for specific antigens showed the similarity of NS-SV-DC, NS-SV-MC, NS-SV-AC, and NS-SV-SC to duct, myoepithelial, acinar, and squamous cells, respectively. Anchorage-independent growth in soft agar and tumorigenicity in nude mice were not recognized in all cell clones. These results demonstrate that establishment of cell clones with duct-, myoepithelial-, acinar-, or squamous phenotype was accomplished in the in vitro system, and that based on the evaluation of colony-forming ability in soft agar and tumorigenicity in nude mice these cell clones can be considered to be non-tumorigenic. Using the above in vitro system, we examined the effect of a reconstituted basement membrane extract, Matrigel, on the morphogenesis of cultured normal human salivary gland cells. When NS-SV-DC or NS-SV-MC were seeded on Matrigel in serum-free culture conditions, they formed round or zonal clusters on day 1; failing however, to develop into a salivary gland morphogenesis. Semithin sections of cell clones cultured on Matrigel exhibited multicellular aggregates on day 1, while on days 2 and 3 these cells lost both cell-cell and cell-Matrigel interactions and eventually entered crisis. In an attempt to understand the mechanism involved in this phenomenon, we have investigated proteolytic enzymes and their inhibitors secreted by cell clones. Although cell clones produced almost identical levels of gelatinases, they released increased amounts of plasminogen activators (PAs) as compared with a neoplastic human salivary gland cell line (HSG), which had already been demonstrated to differentiate into acinar cells when cultured on Matrigel. Obvious difference of expression level of tissue inhibitor of metalloproteinases-1 (TIMP-1) was not observed in these cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Gustatory responsiveness of chorda tympani fibers in the cynomolgus monkey

Responses of chorda tympani (CT) fibers of cynomolgus monkeys to various gustatory stimuli were analysed to obtain quantitative data on their response properties and to reveal the coding of gustatory information. Based on responses of 66 fibers to the four basic gustatory stimuli, they were classified into 16 sucrose-best, 28 NaCl-best, 11 HCl-best and 11 QHCl (quinine hydrochloride)-best fibers. Sucrose-best fibers were narrowly tuned to sucrose, while HCl-best fibers were broadly tuned to the four stimuli. The average breadth of response measure. H for all the 66 fibers was 0.375. The average value of H for sucrose-, NaCl-, HCl- and QHCl-best fibers was 0.276, 0.348, 0.634 and 0.384, respectively. Hierarchical cluster analysis performed on responses of 25 fibers to 14 gustatory stimuli revealed that all the stimuli except for 0.3 M Na-saccharin were grouped into four clusters; sucrose and 0.01 M Na-saccharin, NaCl and LiCl, acids, and non-sodium and -lithium salts, and QHCl. It is concluded that in the monkey CT each of the four classes of fibers predominantly contributes to mediate gustatory information for sweet, salty, sour and bitter stimuli.

Visualization of renal microcirculation in isolated Munich-Wistar rat kidneys: effects of endothelin-1 on renal hemodynamic activity

The aim of the present study was to visualize the superficial glomeruli of the Munich-Wistar (MW) rat and to characterize the responses of the renal microvasculature to endothelin-1 (ET-1). We first examined the distribution of superficial glomeruli of the MW rat compared to that in a control strain (Wistar rat). Secondly, we examined the effects of ET-1 on the renal microcirculation of the MW rat. The right kidney was perfused with a Krebs-Ringer solution containing fluorescein isothiocyanate dextran (FITC-dextran) and was visualized under an epi-illuminated fluorescence microscope system. Changes in perfusion pressure and diameter of the microvessels accompanying the administration of ET-1 (10 fmole-300 pmole) were measured. The number of superficial glomeruli was greater in the MW rat than in the Wistar rat. ET-1 had long-lasting and dose-dependent pressor effects. Perfusion pressure showed a 3.5-fold increase compared with the control, and the afferent arterioles showed greater dose-dependent vasoconstriction than the efferent arterioles. These findings suggest that the MW rat is a useful animal model for the study of renal microcirculation and that the renal microcirculation is extremely sensitive to ET-1.

Far less frequent mutations in ras genes than in the p53 gene in skin tumors of xeroderma pigmentosum patients

Mutations in Ha-ras, Ki-ras, and N-ras genes in squamous and basal cell carcinomas in patients with xeroderma pigmentosum (XP) were examined by the polymerase chain reaction followed by single-strand conformation polymorphism analysis and direct base sequencing. No mutation was detected in codons 12, 13, and 61 of the ras genes in XP skin tumors. This was in contrast with previous findings of a high frequency of mutation in the p53 gene in skin tumors in XP patients. A novel mutation in codon 6 of the Ki-ras gene was detected in a squamous cell carcinoma. The mutation was a C-->T transition at a dipyrimidine (5'-CT) sequence and could have been produced by solar ultraviolet light. The mutated ras gene did not have the ability to transform NIH/3T3 cells. In three tumors, multiple base substitutions were detected in exon 1 of the Ki-ras and N-ras genes. These results and our previous work on p53 gene mutations suggest that mutations in ras genes are far less frequent than in the p53 gene in the skin tumors in XP patients and that ras genes are less important in skin tumorigenesis in XP patients than is the p53 gene.

Self-expanding metal stents for palliative treatment of malignant biliary and duodenal stenoses

Patients with malignant biliary stenosis due to pancreatic head cancer often have the associated problem of duodenal obstruction. We report here the case of a 78-year-old woman with this clinical situation, who was treated with self-expanding Gianturco metal stents placed in the distal common bile duct and, nine months later, placed in the descending duodenum. The patient's frequent vomiting resolved, and she was able to tolerate peroral solid food; jaundice also decreased (bilirubin pre-stenting: 7.8; post-stenting: 1.2). Self-expanding metal stents therefore appear to be effective for the palliative treatment of malignant duodenal stenosis as well as biliary stenosis.

A highly enhanced thrombopoietic activity by monomethoxy polyethylene glycol-modified recombinant human interleukin-6

Interleukin-6 (IL-6) is a novel cytokine with activities that can affect hematopoietic cells including those of the megakaryocytic lineage. We have examined the effects of monomethoxy polyethylene glycol-modified recombinant human interleukin-6 (Peg-IL-6) on thrombopoiesis in vivo. To compare the thrombopoietic activity between Peg-IL-6 and unmodified IL-6, each was administered subcutaneously to mice every 24 hours at various doses. A dose-response experiment showed that Peg-IL-6 and IL-6 increased platelet counts in a dose-dependent fashion at a plateau stimulation level of 0.5 micrograms/day and 10 micrograms/day, respectively. This dose of Peg-IL-6 and IL-6 induced the elevated platelet counts by approximately 140% to 160% and 50% to 60%, respectively. Peg-IL-6 treatment (0.5 micrograms/day) for x-ray (6.0 Gy) irradiated mice induced an increase in the rate of platelet recovery, and a higher dosage (5 micrograms/day) completely blocked the induction of thrombocytopenia in this model. In contrast, IL-6 (10 micrograms/day) could not protect the animals from platelet nadir but reduced the period of thrombocytopenia after x-ray irradiation. Furthermore, when administered to 5-fluorouracil-treated mice, 5 micrograms/day of Peg-IL-6 diminished the platelet nadir and increased platelet counts on individual days during the recovery phase. The potent thrombopoietic activity of Peg-IL-6 were due to prolongation of circulating IL-6 levels that were reverted from Peg-IL-6 in vivo. These findings indicate that reduction of total body clearance of IL-6 induces potent thrombopoiesis and that Peg-IL-6 may be a useful thrombopoietic agent.

[Effect of mesalazine microgranules on experimental colitis]

Mesalazine microgranules are an ethylcellulose-coated formulation from which mesalazine is released throughout the intestinal tract and are expected to be effective for idiopathic inflammatory bowel disease, ulcerative colitis and Crohn's disease. Mesalazine microgranules were administered orally to investigate the distribution of mesalazine throughout the intestinal tract in rats. Mesalazine microgranules distributed sufficient amounts of mesalazine and its metabolite, N-acetyl-mesalazine, to the intestinal tissues, while pure mesalazine delivered lower amounts of both. In acetic acid-induced colitis in rats, mesalazine microgranules administered orally reduced the damage score significantly (P < 0.05) at a dose of 50 mg/kg as assessed by macroscopic observation and at 100 mg/kg as assessed by histological evaluation. The number of ulcers in carrageenan-induced colitis in guinea pigs was inhibited at doses of 50, 100, 200 mg/kg, p.o. The colonic wet weight of rats in 2,4,6-trinitrobenzenesulfonic acid (TNB)-induced colitis was reduced significantly (P < 0.05) at a dose of 50 mg/kg, p.o. Mesalazine microgranules showed the ability to distribute mesalazine efficiently throughout the intestinal tract and showed effectiveness against acetic acid-, carrageenan- and TNB-induced colitis. These studies strongly suggest that mesalazine microgranules are effective for idiopathic inflammatory bowel disease.