Proteolytic processing and membrane association of putative nonstructural proteins of hepatitis C virus

By using a plasmid-based transient protein expression system in cultured cells and an in vitro transcription/translation system, we analyzed the proteolytic processing of the putative nonstructural protein region of the precursor polyprotein from a Japanese type of hepatitis C virus. In addition to the previously reported viral proteins, p21 and p70, we identified products of 4 kDa (p4), 27 kDa (p27), 56 kDa (p56), 58 kDa (p58), and 66 kDa (p66). These products were produced in a viral serine proteinase (proteinase 2)-dependent manner from the region downstream of p70 in the precursor polyprotein and were arranged as NH2-p70-p4-p27-p58(p56)-p66-COOH as determined with region-specific antibodies. We showed that p56 was an N-terminally truncated form of p58, which suggested that a small polypeptide of 2 kDa (p2) was produced from the N-terminal part of p58. Cleavage between p4 and p27 was inefficient in vitro and we saw the 31-kDa precursor polypeptide (p31) accumulate. Furthermore, efficient cleavage at this site in vivo required the presence of p58/p56. Immunoprecipitation analysis in vitro also suggested the mutual interaction of those nonstructural protein products. An especially close association of p4 with p70 may contribute to association of p70 with microsomal membranes.

Operative stress potentiates the inductivity of membrane associated lymphotoxin (mLT) on lymphokine activated killer (LAK) cells in vitro

Membrane-associated lymphotoxin (mLT) is induced in human peripheral blood mononuclear cells when cultured with interleukin 2, in the form of lymphokine-activated killer (LAK) cells. The inductivity of mLT is thought to be dependent upon the differentiation potential of LAK cell precursors, being T cells and natural killer cells. In this study, we investigated the inductivity of mLT on LAK cells from surgical patients. The preoperative values of mLT inductivity were found to be generally higher in malignant than benign cases, and the postoperative time course of mLT inductivity showed a transient decrease immediately after the operation followed by gradual increase over 2 weeks. Moreover, patients with an intraoperative bleeding volume of more than 1,000 ml showed a delay in the postoperative increase of mLT inductivity. These data suggest that operative stress potentiates the inductivity of mLT on LAK cells; however, excess stress may cause a delay in the restoration of mLT inductivity.

Membrane-associated lymphotoxin expression and functional analysis of lymphokine-activated killer cells derived from tumor-infiltrating lymphocytes

The expression of a membrane-associated lymphotoxin molecule (mLT) on lymphokine-activated killer (LAK) cells obtained from 18 patients with malignant tumors and its role in the tumor cell killing mechanisms were investigated. LAK cells from tumor-infiltrating lymphocytes (TIL-LAK cells) were mainly composed of CD3-positive cells, whereas LAK cells from peripheral blood lymphocytes (PBL-LAK cells) were mainly composed of CD16- and CD56-positive cells. However, mLT was found to be expressed on TIL-LAK cells as well as PBL-LAK cells. The degree of mLT expression correlated with the killing activity of LAK cells towards L929 cells (r = 0.806, P < 0.01, n = 15), but not with that towards Daudi or K562 cells. Although the degree of mLT expression correlated with the amount of secreted lymphotoxin (LT) in the supernatant of LAK cell culture, the secreted LT itself could not account for the tumor cell killing activity of LAK cells. Polyclonal rabbit anti-LT antibody partially inhibited the killing activities of LAK cells towards L929 cells and this inhibition was found in the combination of autologous tumor cells and PBL-LAK cells. These findings suggest the possibility that the mLT-related cytotoxicity is involved in the tumor cell killing mechanisms of TIL-LAK cells as well as PBL-LAK cells.

[The study of senile symptoms and home care on the elderly living in Korea]

The purpose of this study is to investigate the daily life and care condition of elderly people living in Korea, and to observe the symptom of senile dementia among them. In the first survey, 713 subjects were screened and 42 subjects were diagnosed as suffering from senile dementia. In the second survey, 26 elderly and their caregivers who agreed to participate in this program, were interviewed. The results were as follows. 1. About 25% of the 713 subjects needed some kind of help in their daily life. 2. 85% of the subjects could go out and about their houses without help. Only 5% of them had a complete or a partial loss of activity. 3. Of all the subjects, 42 were diagnosed as suffering from senile dementia. The prevalence of this disease was calculated at 5.6% in the survey. 4. Each demented elderly person had 5.3 mental symptoms on the average. Depression was observed more among women and violence was observed more among men. 5. The elderly who had a lower CPR score (Caretaker-Patient Relationship Score), indicating a poor relationship between the patient and caretaker, had a higher prevalence of mental symptoms than those who had a higher CPR score.

[A late phase II comparative study of idarubicin + cytarabine and daunorubicin + cytarabine in adult patients with acute non-lymphocytic leukemia. Idarubicin Study Group]

In adult patients with acute non-lymphocytic leukemia (ANLL), idarubicin (IDA) and daunorubicin (DNR) were compared for efficacy and safety in combination with cytarabine (Ara-C). IDA 12 mg/m2/day and DNR 40 mg/m2/day were administered iv bolus for 3 consecutive days (day 1-3), respectively, in combination with Ara-C 80 mg/m2 given by 2-hour intravenous infusion, every 12 hours for 7 consecutive days. The number of evaluable patients was 32 for each group previously untreated. The rates of complete remission (CR) were 59.4% (19/32) in the IDA group and 40.6% (13/32) in the DNR group. The clinical equivalence test with delta = 10% demonstrated that the IDA group is equal or superior in remission rates (p = 0.010) compared to the DNR group. In addition, the Cochran-Mantel-Haenszel test for response means with scores of 3 (CR), 2 (PR) and 1 (NR) showed the significant superiority (p = 0.044) of the IDA group to the DNR group. The duration needed to attain less than 5% leukemic cells in bone marrow tended to be shorter in the IDA group (p = 0.072), and in the CR patients the number of days needed to reach the nadir value in leukemic cells were significantly fewer in the IDA group (p = 0.037). The nadir value of WBC was significantly lower in the IDA group (p = 0.022). As for adverse reactions, high incidences of diarrhea and stomatitis were observed in the IDA group, while the incidences of other adverse reactions were similar between the two groups. When effects of the drug on the ECG were examined, significant changes in ECG parameters were observed in the DNR group after treatment but not in the IDA group. From the above, remission induction in adult AN LL, IDA + Ara-C therapy showed better efficacy than DNR + Ara-C therapy, and IDA was considered to be a drug of first choice in the treatment of ANLL patients.

Human corticotropin-releasing hormone test in patients with hypothalamo-pituitary-adrenocortical disorders

To assess the diagnostic usefulness of a synthetic human corticotropin-releasing hormone (CRH) formulation (Code No. MCI-028), we administered 100 micrograms of the peptide intravenously to 183 patients with hypothalamo-pituitary-adrenocortical (HPA) disorders, and obtained the following findings. Among the 183 patients, data from 125 patients were suitable for analyzing the effects of the test. In patients with Cushing's disease, high plasma adrenocorticotropic hormone (ACTH) and cortisol levels increased further in response to MCI-028, while in patients with adrenal Cushing's syndrome, low ACTH and high cortisol values remained unchanged. In patients with pituitary-type hypopituitarism or isolated ACTH deficiency, low ACTH and cortisol levels responded poorly or insignificantly to MCI-028, whereas those with hypothalamic hypopituitarism showed delayed and considerable degree of responses of plasma ACTH and little increase in plasma cortisol levels. In Addison's disease, high plasma ACTH increased further in response to MCI-028, but low cortisol levels did not change. In patients with Cushing's syndrome soon after successful surgical treatment, plasma ACTH responsiveness was low or different depending on the clinical course of the patient. Patients treated with high doses of glucocorticoids for non-endocrine diseases tended to show impaired ACTH and cortisol responsiveness to MCI-028. Side effects, including the transient flushing which was observed most frequently in this study, did not cause any clinical problems.

[A late phase II study of idarubicin hydrochloride in adult patients with acute lymphocytic leukemia. Idarubicin Study Group]

A late phase II study of idarubicin hydrochloride combined with vincristine and prednisolone was conducted in adult patients with acute lymphocytic leukemia (ALL) in the first relapse as a multi-center joint research project. The dosages used were idarubicin 12 mg/m2/day i.v. for 3 consecutive days (day 1-3), vincristine 1.4 mg/m2 i.v. (day 1) and prednisolone 60 mg/m2/day po for 5 consecutive days (day 1-5). The number of evaluable patients was 20. The patients showed responses including 3 complete remissions (CR) and 10 partial remissions (PR), with an efficacy rate (CR + PR) of 65.0%. Adverse reactions occurred in 19 of 20 patients. The main symptoms were gastrointestinal symptoms including anorexia, nausea/vomiting, and stomatitis and fever, infection, and alopecia. Abnormal laboratory data were observed in 6 of 20 patients with 13 events. Although one case of an increase in GPT with WHO grade 3 was observed, the other cases were not of significance. From the above study, idarubicin hydrochloride was considered to be effective in relapsed ALL patients in combination therapy with vincristine and prednisolone.

Adaptive changes in zonation for gluconeogenic capacity in liver lobules of cold-exposed rats

The rate of gluconeogenesis from lactate increased in perfused livers after exposure of rats to cold for 5 days, and it returned to the control rate after 20 days [M. Shiota, T. Tanaka, and T. Sugano. Am. J. Physiol. 249 (Endocrinol. Metab. 12): E281-E286, 1985.]. The relationship between the increased gluconeogenic activity and its zonal distribution in liver lobules was studied in cold-exposed rats that had been starved for 24 h by examination of preparations enriched for periportal hepatocytes (PP-H) and for perivenous hepatocytes (PV-H), which had been isolated by the digitonin-collagenase perfusion technique. In the control group, the rate of gluconeogenesis from lactate or alanine was three times higher in PP-H than in PV-H. The rate of gluconeogenesis from these substrates in PP-H was not changed by exposure of rats to cold. The rates of PV-H increased to the level in PP-H after 5 days of exposure of rats to cold and then returned to the control rates after 20 days. The rate of gluconeogenesis from fructose was not altered in either preparation of cells by cold treatment of rats. The change in gluconeogenic capacity in PV-H caused by exposure of rats to cold was unrelated to changes in the activity of the malate-aspartate shuttle and of pyruvate kinase. The increased capacity in mitochondrial respiration was observed in both preparations of cells by cold treatment of rats for 5 days. The activity of phosphoenolpyruvate carboxykinase was higher in PP-H than in PV-H in the control group.(ABSTRACT TRUNCATED AT 250 WORDS)

Spontaneous submucosal dissection of the esophagus

A 41-year-old woman was found to have had spontaneous submucosal dissection of the esophagus by esophagoscopy. Food ingestion was postulated to have been an initiating factor in this instance. Conservative therapy was sufficient in this case. Patients who complain of sore throat with retrosternal pain and an obstructed sensation on swallowing or mild hematemesis should be examined by esophagoscopy for evidence of this disorder.

Ductus arteriosus. Advanced differentiation of smooth muscle cells demonstrated by myosin heavy chain isoform expression in rabbits

BACKGROUND

The closure of the ductus arteriosus (DA) is one of the most striking cardiovascular events that occur at birth. It has been attributed to oxygenation and intrinsic prostaglandins. However, selective constriction of DA suggests the presence of highly specialized contractile mechanisms in DA. We previously reported that smooth muscle myosin heavy chain isoforms, SM1 and SM2, are molecular markers for smooth muscle differentiation because of their unique expression pattern during vascular development. SM1 and SM2 are generated from a single gene through developmentally regulated alternative RNA splicing; SM1 is expressed in almost all stages of differentiation of the vascular smooth muscles, but SM2 is found only after birth.

METHODS AND RESULTS

Immunohistochemistry was performed to study the expression of the different types of myosin heavy chain isoforms in DA of fetal and neonatal rabbits. Electron microscopic examinations were also carried out to demonstrate ultrastructural characteristics of ductus muscles. We found that SM2 is expressed before birth in the medial layer of DA, indicating advanced differentiation of smooth muscle cells in DA. The exact location of immunoreactivity for SM2 was in the smooth muscle cell of the medial layer of DA. Immunoreactivity for SM1, however, was not different for DA and adjacent great arteries. Transmission electron microscopy demonstrated greater amounts of myofilaments in medial smooth muscles of DA than those of aorta.

CONCLUSIONS

These results indicate that smooth muscles in DA are more differentiated than those in other arteries, which may be one of the cellular mechanisms responsible for the unique closure of DA at birth.

[The relaxation of human corpus cavernosum caused by nitric oxide]

Non-adrenergic non-cholinergic nerves (NANC) are thought to be important in the relaxation of corpus cavernosum for erectile function. On the other hand, it has been shown that nitric oxide (NO) is synthesized from L-arginine and released by the endothelium of blood vessels and accounts for the activity of endothelium-derived relaxing factor (EDRF). We studied whether electrical field stimulation (EFS) of isolated strips of human corpus cavernosum released NO and whether it could act as a NANC neurotransmitter. Human penile tissue specimens were mounted in an organ bath and the isometric tension recorded. EFS was applied to precontracted strips between two parallel platinum electrodes. Relaxation induced by EFS was not influenced by guanethidine or atropine, but was markedly inhibited by NG-nitro-L-arginine which is an analog of L-arginine that inhibits the conversion of L-arginine to NO, and hemoglobin which is an agent that inhibits the biological actions of NO. Methylene blue which is an inhibitor of cytosolic guanylate cyclase also reduced the relaxation of EFS, but not completely. The inhibitory effect of NG-nitro-L-arginine was reversed by addition of excess L-arginine. Exogenous NO relaxed human corpus cavernosum. The relaxation was only a transient response and concentration-dependent. The profile of responses is similar to that evoked by EFS. Our data clearly demonstrate the release of NO during EFS and the function of NO as a NANC neurotransmitter. Human penile erection may be mediated by NO generated in response to NANC neurotransmission.

Posterior sagittal rectal myectomy for persistent rectal achalasia after the Soave procedure for Hirschsprung's disease

For the management of persistent rectal achalasia after the Soave endorectal pull-through procedure, we have used posterior sagittal myectomy of the remaining aganglionic rectal muscular cuff, and have had satisfactory outcomes in five patients. Via a posterior sagittal skin incision, the posterior aspect of the rectal muscular cuff is reached. With the striated muscular complex retracted downward, the level of the dentate line is identified on the posterior wall of the rectum with the aid of the surgeon's finger inserted inside the anorectum. Two parallel longitudinal incisions are made on the rectal muscular cuff to create a muscular strip which is elevated and excised; the distal end of the myectomy strip is at the level of the dentate line and includes a part of the internal and sphincter muscle. During the last 4 years, we performed this procedure in 5 patients with remarkable relief of constipation, distension, and enterocolitis. The advantages of this procedure include: (1) less technical difficulty than the transanal approach, (2) avoiding colostomy, and (3) promising results.

[Studies on the reduction and correction risk factors for arteriosclerosis in junior high school pupils]

Circulatory system examinations performed on first-grade pupils of junior high schools (12 years old; N = 1,204), identified 105 high-risk pupils with arteriosclerosis-promoting factors. These pupils were consulted on life-style modification, emphasizing nutrition and exercise, and encouraged to practice personal health management and self-monitoring. Reduction and correction of high risk factors were studied in these subjects, based on review of results of health examinations performed regularly up to the time of their graduation. Results are as follows: 1. Averages for obesity grade (for both sexes) in the second and the third years were significantly lower than that in the first year. Based on a general reference value > or = 20%, improvements were observed in 22.5% of males and 50.0% of females. 2. In both sexes average total cholesterol (TC) and triglyceride (TG) were lower in the second and the third years than in the first year, and a significant increase in HDL cholesterol was seen. With regard to a general reference value > or = 3.0 for AI (Atherogenic Index) calculated using TC and HDL cholesterol, improvements (reduction) were observed in 29.4%, of males and 46.2% of females. 3. While the numbers of subjects with elevated SBP, DBP, GPT, FPG and BUN were few, there were significant decreases in averages in the second and third years compared with those in the first year. Using general reference values, improvements in these risks were seen in 100% for all values except for GPT where 75.0% showed improvement. 4. Comparison of grouped distribution of summed values of examination results between the first year and the third year, showed improvements (reduction and correction of risks) in 69 pupils (65.7%), while 30 pupils (28.6%) remained in the same group with no improvement and 6 pupils (5.7%) turned for the worse, dropping one rank.(ABSTRACT TRUNCATED AT 250 WORDS)

Morphometric analysis of renal arterioles in subtotally nephrectomized rats

Renal arteriolar diameters were measured by using vascular casts in the remnant kidneys of subtotally nephrectomized rats. Two weeks after nephrectomy, both afferent and efferent arterioles were dilated, with development of glomerular hypertrophy. Thirteen weeks after nephrectomy, the afferent arteriole was dilated further, while the efferent arterioles became constricted. Glomerular hypertrophy was augmented. At this stage, the systemic pressure was elevated, with development of marked glomerular sclerosis. Throughout the experiment, captopril lowered the systemic pressure, suppressed glomerular hypertrophy, and limited glomerular damage. Both the afferent and efferent arterioles were dilated further. Changes in the arteriolar diameters and the systemic blood pressure suggested that elevated glomerular pressure existed in the remnant kidney and did not exist in the captopril-treated remnant kidney throughout the experiment. Hydralazine and trichloromethiazide therapy lowered the systemic pressure and maintained the arteriolar diameters and glomerular size at normal levels. However, at the late stage, afferent and efferent arterioles were dilated, with development of glomerular hypertrophy and severe glomerular sclerosis. The results suggested that elevated glomerular pressure was involved in development of glomerular sclerosis. However, factors other than hemodynamics should be considered in the pathogenesis of glomerular sclerosis. A direct causal relationship between glomerular hypertrophy and glomerular damage was not shown because captopril ultimately limited glomerular sclerosis despite glomerular hypertrophy at the early stage, and hydralazine and trichloromethiazide therapy did not ultimately ameliorate the glomerular sclerosis despite normal glomerular size at the early stage.

Two proteinase activities in HCV polypeptide expressed in insect cells using baculovirus vector

Processing of HCV viral precursor protein requires at least two viral proteinases, Cpro-1 and Cpro-2, in addition to cellular proteinases. The HCV polypeptide that covers the region for the two viral proteinase domains was expressed in insect cells using a baculovirus expression system. The two proteinase activities were demonstrated in the infected cells. The Cpro-1-dependent cleavage site was estimated from the amino acid sequence of the N-terminus of the processed product. Analyses of the susceptibilities of various mutants altered at position P1 and P1' of the putative cleavage site suggested that amino acid residues at these positions is not essential for recognition and cleavage by Cpro-1-dependent activity.

Hemodynamics of the left gastric vein in portal hypertension

BACKGROUND

Esophageal varices reflect the hemodynamics of the left gastric vein, which can now be studied by Doppler ultrasonography. The purpose of this study was to elucidate the hemodynamic features of the left gastric vein in portal hypertension.

METHODS

Flow direction and velocity in the left gastric vein were examined by the pulsed Doppler flowmeter in 53 healthy adults and 216 patients with liver cirrhosis.

RESULTS

Flow direction was hepatopetal in all healthy controls, whereas it was hepatofugal in 72% of the patients with esophageal varices. In the early stage of mild esophageal varices, flow direction was still hepatopetal. However, in portal pressure > 250 mm H2O, hepatofugal flow was highly frequent (56 of 59 patients, 95%). Hepatofugal flow velocity in patients with varices was 8.5 +/- 2.5 cm/s in mild varices, 11.6 +/- 2.4 cm/s in intermediate varices, and 13.8 +/- 3.4 cm/s in marked varices. Variceal bleeding was frequent in patients with a flow velocity > 15 cm/s (7 of 14 patients, 50%). Flow velocity in the left gastric vein increased after ingestion of glucose in 43 of 56 patients with esophageal varices.

CONCLUSIONS

In portal hypertension, as the size of varices enlarged, hepatofugal blood flow in the left gastric vein increased in parallel. High flow velocity in the left gastric vein was strongly associated with variceal bleeding. Increase of blood flow after ingestion of glucose suggests postprandial increase in variceal flow.

[Transition of diagnosis and treatment for impotence]

Statistic study was made on 685 outpatients with erectile dysfunction during 13 years periods from 1979 to 1991 in the Department of Urology, Takamatsu Red Cross Hospital. The age distribution showed the highest frequency in the thirties decade (27.9%). 1. Diagnosis Nocturnal penile tumescence monitoring was the only method to distinguish organic impotence from functional impotence during the first 5 years. From 1984 we have been able to diagnose corporal veno-occlusive insufficiency (CVI) by papaverine test and dynamic infusion cavernosometry and cavernosography. Measurement of penile brachial index and pelvic angiography were performed to diagnose arterial insufficiency (AI). In neurological examination we have measured bulbo-cavernosus reflex latency and nerve conduction velocity of the dorsal penile nerve and performed microvibration measurement and sweat spots test. All diagnostic methods were established in 1987 and we have been able to classify about 80% patients. We classified 305 patients during the last 5 years from 1987 as follows: psychogenic; 31.1%, CVI; 20.0%, AI; 7.9%, neurogenic; 7.9%, others; 14.1%, drop-out and unknown; 19.0%. 2. Treatment In the beginning only counseling and drug therapy were performed. However we lately performed various suitable methods for individuals based on their diagnoses. We performed counseling, drug therapy and intracavernous injection of vasoactive drug therapy for recovery of spontaneous erection (vascular training) for psychogenic IMP. The efficacy rate of counseling was low (30.4%) but that of drug therapy was 41.6%, and that of vascular training, 64.2%. For CVI without other factors we performed venous surgeries. Only about 25% of them perform sexual intercourse with or without self injection of vasoactive drug (self injection).(ABSTRACT TRUNCATED AT 250 WORDS)

The internal branch of the superior laryngeal nerve in the dog distributes to the esophageal gland at the pharyngo-esophageal junction

The annular plica (plica anularis) of the cervical esophagus contained mucous glands in dogs. Specimens, impregnated with the silver nitrate, were examined under a dissecting microscope. The internal branch of the superior laryngeal nerve lay fibers in close contact with the terminal portion and excretory duct of glands.

Absorption in the isolated bowel segment

An isolated bowel segment (IBS) is a viable mesenteric segment of intestine. This study was undertaken to investigate the effects of mesenteric vascular and neural supply on intestinal absorption. Ten rats were used for leucine absorption and another 10 for glucose absorption experiments. L-leucine, 12 ml of 15.0 mM/L, or 3.0 mM/L of D-glucose solution were recirculated through the IBS (n = 5) and rat jejunum that underwent sham operation (n = 5) at 2.56 ml/min for 90 min. Absorption was expressed as millimoles of leucine or glucose per gram of mucosal protein. The Student's t test was used for statistical analysis; a p < or = 0.05 was considered significant. The net absorption of L-leucine was 36.20 +/- 3.31 mM/g of mucosal protein in the IBS and 15.52 +/- 1.48 mM/g of mucosal protein in the control group (p < 0.001). The net absorption of D-glucose was 3.82 +/- 0.26 mM/g of mucosal protein in the experimental group and 4.34 +/- 0.31 mM/g of mucosal protein in the control group (p = 0.02). This study concludes that absorption of leucine and glucose in the IBS is preserved after mesenteric division.

Antiasthma drug, ibudilast, inhibits neurogenic plasma extravasation in guinea-pig airways

We examined the effect of ibudilast, an antiasthma drug, on neurogenic microvascular leakage in guinea-pig airways by measuring extravasation of Evans blue dye. After intravenous pretreatment with atropine (1 mg/kg) and propranolol (1 mg/kg), bilateral vagal stimulation significantly increased nonadrenergic noncholinergic (NANC)-mediated leakage of dye in the trachea (Tr), the main bronchi (MB), and the central (cIPA) and peripheral (pIPA) intrapulmonary airways. Ibudilast (1.0 to 100 micrograms/kg given intravenously) did not affect basal leakage, but it significantly inhibited NANC-mediated plasma extravasation in a dose-dependent manner, with a maximal inhibition of 74.0% (Tr, p < 0.05), 89.1% (MB, p < 0.05), 91.4% (cIPA, p < 0.01), and 84.3% (pIPA, p < 0.05) at 100 micrograms/kg. Plasma extravasation induced by exogenous substance P (1 microgram/kg given intravenously) was not inhibited by ibudilast. Glibenclamide, an inhibitor of ATP-sensitive potassium channels, blocked the inhibitory effect of ibudilast. We conclude that ibudilast inhibits neurogenic leakage by prejunctional inhibition of neuropeptide release from airway sensory nerve terminals via an ATP-sensitive potassium channel.