Involvement of specific mechanism in plasmid DNA uptake by mouse peritoneal macrophages

The binding and uptake of plasmid DNA encoding luciferase reporter gene (pCMV-Luc) were studied in vitro using cultured mouse peritoneal macrophages. A significant and time-dependent cellular association of [32P]pCMV-Luc with resident macrophages was observed at 37 degrees C and this decreased at 4 degrees C. The binding at 4 degrees C was saturable and a Scatchard plot gave a maximum binding capacity of 0.81 microgram/mg-protein and a dissociation constant of 0.30 microgram/ml. The binding of [32P]-pCMV-Luc was inhibited by polyinosinic acid, dextran sulfate and salmon sperm DNA, but not by polycytidylic acid, dextran and EDTA. A confocal microscopic study demonstrated that fluorescein-labeled pCMV-Luc was internalized at 37 degrees C while only cell surface binding occurred at 4 degrees C. No significant luciferase gene expression was obtained after incubation with a high concentration (100 micrograms/ml) of pCMV-Luc. These data suggest that plasmid DNA is taken up by macrophages via a mechanism mediated by a receptor like the macrophage scavenger receptor.

Recurring encephalopathy abolished by gastrorenal shunt ligation in a diabetic hemodialysis patient

A 57-year-old man was admitted to our hospital for hepatic encephalopathy. He previously had undergone a partial gastrectomy for gastric ulcer, and also had been on maintenance hemodialysis because of diabetic nephropathy. Despite treatment with branched-chain amino acids and lactulose, encephalopathy occurred repeatedly. The findings of his laboratory examinations, computed tomography, and liver biopsy were not suggestive of chronic liver damage. Angiography revealed a portal-systemic shunt from the superior mesenteric vein via the left gastric vein to the left renal vein. A ligation of the gastrorenal shunt was performed. After the shunt ligation, hepatic encephalopathy no longer recurred, and no medication was required to prevent it. The insulin requirements also decreased, the plasma ammonia concentration then decreased, and serum concentration of several amino acids related to the ammonia metabolism also decreased. The molar ratio of branched-chain amino acids to aromatic amino acids increased. The ligation of the portal-systemic shunt was thus considered to be the key to the successful treatment of hepatic encephalopathy in this unusual case.

A rare case of hepatic injury associated with ovarian hyperstimulation syndrome

A 26-year-old married woman was admitted to our hospital because of massive ascites and hepatic injury. The patient had been treated with human menopausal gonadotropin and clomiphene citrate to prevent recurrence of spontaneous abortions. About 1 month later, she developed upper abdominal pain and noticed dark urine. On admission, she had elevated concentrations of serum transaminases with an asparate aminotransferase of 127 IU/L and alanine aminotransferase of 194 IU/L. An abdominal ultrasound showed massive ascites. Her serum concentration of estradiol was high at 12,100 pg/mL, which was much greater than the value of early stage of pregnancy (2,279-7,353 pg/mL). She was thus diagnosed as having ovarian hyperstimulation syndrome. Following a period of bed rest, her liver function normalized and the ascites disappeared. Based on the above findings, the patient was considered to have suffered from ovarian hyperstimulation syndrome, complicated by hepatic injury.

[Thyroid function in patients with Yusho: 28 year follow-up study]

To evaluate chronic effect of polychlorinated biphenyl (PCB) on thyroid functions, thyroid hormone levels and thyroidal autoantibodies were studied in 81 patients with Yusho in 1996. Serum level of thyroid stimulating hormone (TSH) was elevated in 7 cases (8.6%). All of them showed normal triiodothyronine (T3), thyroxine (T4) and free T4 levels, and regarded as latent hypothyroidism. There were no significant correlations between blood PCB concentrations and TSH levels, T2 levels, T4 levels or free T4 levels. Thyroglobulin antibodies were detected in 8 cases (19.5%) of 41 Yusho patients with high PBC concentration (higher than 3.0 ppb), and in only one case (2.5%) of 40 patients with low PBC concentration (lower than 2.9 ppb). We conclude that thyroglobulin antibody in patients with Yusho is not frequent and it may be associated with blood PCB concentration.

No effect of high-protein food on the stereoselective bioavailability and pharmacokinetics of verapamil

The effects of high-protein food on the bioavailability of both the racemate and individual enantiomers of verapamil were investigated in 12 healthy volunteers using a randomized crossover design. Food had no effect on any parameter of bioavailability for both the racemate and the individual enantiomers of verapamil except time to maximum concentration (tmax), which was significantly prolonged after food intake. The pharmacokinetics of the enantiomers of norverapamil were not significantly changed by food intake. These results suggest that high-protein food does not alter the pharmacokinetics and bioavailability of either the racemate or the individual enantiomers of verapamil. Therefore, the clinical efficacy of verapamil is not related to food intake, except for a slight prolongation in the time to onset of the pharmacologic effects. The present data can be applied to the high-protein content meal intake.

[Fucosyltransferase producing sialyl Le(a) and sialyl Le(x) carbohydrate antigen in gastrointestinal cancer]

Sialyl Lea and sialyl Lex are cancer-associated carbohydrate antigens. The biosynthesis of these antigens is completed by fucosyltransferases. We measured the activity of alpha 1-->4 fucosyltransferase (sialyl Lea synthase) and alpha 1-->3 fucosyltransferase (sialyl Lex synthase) in gastrointestinal cancer tissues. alpha 1-->4 fucosyltransferase activity was similarly detected in most normal or malignant tissues. alpha 1-->3 fucosyltransferase activity in gastric cancer was higher than in the normal mucosa. In colonic cancer, although the enhanced expression of sialyl Lex was observed in 86% of cases, the elevated activity of alpha 1-->3 fucosyltransferase was observed in only 58%. In conclusion, the expression of sialyl Lea and sialyl Lex antigens in the stomach and colon was not controlled solely by fucosyltransferases.

Fucosyltransferase-producing sialyl Le(a) and sialyl Le(x) carbohydrate antigen in benign and malignant gastrointestinal mucosa

BACKGROUND

Sialyl Le(a) antigen and sialyl Le(x) antigen are cancer-associated carbohydrate antigens. Previous immunohistologic and immunochemical studies have shown that these antigens are preferentially expressed in gastric cancer and colonic cancer and that they possibly are related to the metastatic potential of the cancer cells. The biosynthesis of these antigens is completed by fucosyltransferases, but it has not been reported how fucosyltransferases control the expression of these carbohydrate antigens concerning the invasive potential of the cancer.

METHODS

The authors established an assay system for measuring the activity of alpha 1-->4 fucosyltransferase (sialyl Le(a) synthase) and alpha 1-->3 fucosyltransferase (sialyl Le(x) synthase) with a high-pressure liquid chromatography system (HPLC). The activity was measured in various parts of normal and cancerous gastric and colonic tissue and compared with the expression of sialyl Le(a), sialyl Le(x), Le(a), and Le(x) antigens determined in a solid-phase enzyme-linked immunosolvent assay (EIA).

RESULTS

Sialyl Le(a) synthase was detected in most normal or malignant mucosa of gastric and colonic tissues, regardless of anatomic locations. Sialyl Le(x) synthase activity generally was low in the normal gastric mucosa, whereas the activity was higher in 77% (7 of 9) of gastric cancer tissues than in corresponding normal tissues with enhanced expression of sialyl Le(x) antigen in most patients (5 of 7). In the large intestine, the activity of sialyl Le(a) synthase and sialyl Le(x) synthase was correlated. Although enhanced expression of sialyl Le(x) in colonic cancer was observed in 86% (12 of 14) of all patients, concomitant higher sialyl Le(x) synthase activity than that in normal tissue was observed in only 58% (7 of 12) of patients.

CONCLUSIONS

The expression of sialyl Le(a) and sialyl Le(x) antigens in the stomach and the colon was not controlled solely by fucosyltransferases but by a more complicated system involving other glycosyltransferases.

[Surgical treatment of primary cardiac tumors]

Thirty-four cases of primary cardiac tumors, consisted of 11 men and 23 women, aged between 26 and 80 years have been operated on in our institution. A total of 30 myxomas and four malignant tumors were resected. The clinical presentations included congestive heart failure in 25 patients, tachyarrhythmia in 6, chest pain in 4, and embolism in 10. All 30 myxoma lesions were completely resected, although none of the malignant tumors could be resected completely because of invasion of the tumor to the surrounding tissues. Four patients with malignant tumors died of tumor recurrence within 9 months after operation. Histological diagnosis was rhabdomyosarcoma in two patients, round cell sarcoma in one and malignant fibrous histiocytoma in one. All patients with myxoma survived operation. Follow-up was completed in 28 patients (range 1 month to 15 years, mean 5.5 years): Twenty-four were in New York Heart Association Class I, and the remaining two in Class II. Actuarial survival rate was 89% at 15 years after operation. No recurrent myxoma have been identified clinically or by echocardiography. For malignant primary tumors, more effective adjuvant therapy with aggressive resection will be inevitable to improve long-term prognosis.

[Surgical repair of total anomalous pulmonary venous drainage--four adult cases of successful operation]

We have experienced four adult cases of total anomalous pulmonary venous drainage (TAPVD). They were three females and one male, age between 18-51 with a mean of 33.8. In Darling's classification, they constituted of three cases of type Ia and one type IV. Cardiac catheterization revealed 1.71-5.93 with a mean of 3.92 in Qp/Qs and 0.34-0.49 with a mean of 0.38 in Pp/Ps. The pulmonary to systemic resistance ratio (Rp/Rs) was then calculated as 0.02-0.15 with a mean of 0.09. All cases showed short route type of drainage vein in pulmonary arteriography. None of them had stenosis or obstruction in the drainage veins. The operation was composed of anastomosis between the left atrium and the common pulmonary vein, closure of the atrial septal defect (ASD), and ligation of the drainage vein. Gersony-Malm's method was adopted in two cases and the posterior approach in two cases in anastomoses between the left atrium and the common pulmonary vein. Intraatrial approach combined with posterior approach was tried in a case with small left atrium. The mean size of ASD was 43 mm (35-55 mm) in diameter. Patch closure was performed in three cases. Important factors in survival for adult TAPVD are large ASD and short route type drainage vein without stenosis. All of four cases had good results. The operation method is variable and an easier approach must be adopted.

Acetylation polymorphism of caffeine in a Japanese population

The frequency distribution of N-acetylation of caffeine was determined in 140 unrelated healthy Japanese subjects by measuring the amount of two main metabolites of caffeine, 5-acetylamino-6-formyl-amino-3-methyluracil (AFMU) and 1-methylxanthine (1X), in urine after an oral dose of caffeine. N-Acetylation capacity for caffeine appeared to be polymorphic: 15 subjects (10.7%) were phenotyped as slow acetylators, whereas 125 subjects (89.3%) were phenotyped as rapid ones. The urinary molar excretion ratio of AFMU (AFMU/1X) in 2 hours-urine samples ranged from 0.03 (slow acetylators) to 2.66 (rapid acetylators). The frequency of slow acetylators in this study was similar to that reported previously for the isoniazid and dapsone polymorphism in Japanese populations.

Diurnal effect on caffeine clearance

Caffeine (300 mg) was given orally to nine healthy subjects at 10:00 AM (day trial) or at 10:00 PM (night trial) using a crossover design. Saliva was obtained at 0.5, 1, 1.5, 2, 3, 4, 6, and 8 hours after administration of caffeine. Urine was collected for 8 hours after caffeine dosing. Caffeine clearances in saliva during the day trial were not different from those in the night trial. No significant difference was observed in urinary molar ratios of metabolites (AFMU + 1X + 1U/17U) between the two trials. These data suggest that caffeine clearances in saliva do not vary with its administration time. Since caffeine clearances in plasma are reflected in the urinary ratios of caffeine metabolites, its clearance in plasma might also not be altered by the time of dosing.

Phenytoin partially antagonized L-type Ca2+ current in glucagon-secreting tumor cells (ITC-1)

Transmembrane Ca2+ currents were investigated by means of a whole-cell clamp technique in a hamster glucagon-secreting tumor cell line (ITC-1). Two types of Ca2+ current were identified in ITC-1 cells. The low-threshold and transient (T-type) current became detectable above the potential level around -60 mV and decayed rapidly with an inactivation time constant of 95 ms (at -40 mV and 23 degrees C), while the high-threshold and long-lasting (L-type) one was activated by depolarization more positive to -30 mV with non-inactivating kinetics. The voltage dependence and kinetics of these currents were identical to those reported in guinea-pig pancreatic alpha 2 cells. Both currents were augmented by equimolar substitution of Ca2+ with Ba2+ and completely abolished by adding 1 microM La3+. Phenytoin, a well known anti-epileptic drug and a postulated T-type specific Ca2+ current antagonist, surprisingly blocked the L-type current without affecting the T-type current in ITC-1 cells. While phenytoin antagonized the L-type Ba2+ current selectively, 60% of the current remained even in supramaximal concentration range over 500 microM. The residual component of the L-type current was completely abolished by adding nifedipine.

Surgical treatment of abdominal aortic aneurysm in the high-risk patient

In an attempt to define the preoperative risk factors that predictably influence mortality after aneurysmectomy, this study reviews the surgical management of abdominal aortic aneurysms in a series of 110 consecutive patients who underwent elective resection. The preoperative risks to be added to the present study included pulmonary insufficiency, renal dysfunction, advanced age of over 80 years, ischemic heart disease, and associated other diseases such as thoracic aneurysms, atherosclerosis of the limbs and malignant tumors. Forty-six patients had one of these risk factors (one-risk group), 17 had two (two-risk group), and 9 had three (three-risk group). The operative mortality rates were 4.2 per cent for the high-risk patients and 0 per cent for the patients at no risk. As the number of risk factors increased, aneurysm repair was associated with an increased operative mortality; being 2.2 per cent in the one-risk group, 5.9 per cent in the two-risk group and 11.1 per cent in the three-risk group. The common risk factor in patients who died after aneurysmectomy was pulmonary insufficiency which induced prolonged periods of assisted ventilation. Thus, the optimal management of high-risk patients, particularly those with pulmonary insufficiency, may reduce the mortality after aneurysmectomy.

[Myocardial protection with verapamil in open cardiac surgery--a clinical study for the optimal use]

To determine the optimal use of Verapamil as a myocardial protective agent during open heart surgery, patients were divided into 3 groups of 15 patients each of the same severity and operative difficulty. In group I, Verapamil was added to the blood cardioplegia in a concentration of 1 mg/L. In group II, 0.2 mg/kg of verapamil was added in the pump prime and in group III, in addition to the same amount of pump prime, an additional 0.1 mg/kg of Verapamil was added to the bypass circuit at 60 minutes after the start of bypass and continuous drip of 0.5 micrograms/kg/min for 24 hours after surgery. Only group III continued to maintain an effective concentration of verapamil, that was said in a range between 15 and 100 ng/ml in the serum during and after surgery. It is suggested from the present study that recommendable verapamil administration is as in group III with no severe arrhythmias, significantly less usage of catecholamines without mortality.

[Discrete subaortic stenosis associated with ventricular septal defect and aortic stenotic insufficiency: a report of surgical treatment in the aged]

A 65-year-old man with discrete subaortic stenosis complicated by ventricular septal defect and aortic stenotic insufficiency was successfully operated on. To our knowledge, the present case was the oldest patient who underwent open-heart surgery for discrete subaortic stenosis.

[Seckel's syndrome associated with atrial septal defect: a case report and review of the literature in Japan]

Nine-year-old girl who had Seckel's syndrome (bird-headed dwarfism), one of low birth weight dwarfisms, was successfully operated upon for the associated atrial septal defect. To our knowledge, 17 cases with this syndrome have been reported in Japan. Only three cases including our patient had congenital heart disease.

[Nonsurgical removal of the embolized catheter fragments from the heart and great vessels]

Embolized catheter fragments in the heart and great vessels were successfully removed in seven patients by nonsurgical techniques. All procedures for the retrieval were completed without complications or difficulty using instruments such as multipurpose grasping forceps, stone basket, loopsnare and myocardial biopsy catheters. Embolized catheter fragments should be removed promptly before fatal complications develop, and can be taken off safely and simply by nonsurgical technique.

Suppression of lipoprotein lipase in 3T3-L1 cells by a mediator produced by SEKI melanoma, a cachexia-inducing human melanoma cell line

Production of a cachexia-inducing factor(s) by the SEKI melanoma cell line, established from a human melanoma, has been well documented. Conditioned medium from cultures of this melanoma cell line contains a factor(s) that inhibits the activity of lipoprotein lipase (LPL) in fully differentiated 3T3-L1 adipocytes. The mode of inhibition of this enzyme by the factor, i.e. its dose-dependency and time course, is very similar to that of LPL-inhibition by a macrophage-derived cachexia-inducing factor, cachectin/tumor necrosis factor (cachectin/TNF). However, the conditioned medium of SEKI melanoma cells does not contain any immuno-reactive substances reactive in enzyme-linked immunosorbent assay (ELISA) with anti-cachectin/TNF antibody, or with anti-interleukin 1 alpha or beta antibodies. This LPL-suppression factor present in the conditioned medium seems to be a peptide because of its heat-lability and apparent molecular weight of more than 25,000. The conditioned media from cultures of four other different cell lines were found to show no significant suppression of LPL activity. These results imply that SEKI melanoma cells produce a cachexia-inducing factor(s) similar to cachectin/TNF but that the molecule involved is different.

The necessity of reoperation for patients with Bjork-Shiley, St Jude Medical, Hancock and Carpentier-Edwards prostheses

The purpose of this study was to determine the criteria of valve selection from the long-term results of Hancock, Carpentier-Edwards, St Jude Medical and Bjork-Shiley prostheses, taking into special account the frequency of reoperation. Reoperations on the Hancock bioprosthesis were performed on six patients for tissue leaflet disruption with an incidence of 2.2 per cent/patient-year. Reoperations on the Carpentier-Edwards bioprosthesis were performed on 24 patients for tissue leaflet disruption in 23 patients and prosthetic valve endocarditis (PVE) in one, with an incidence of 3.8 per cent/patient-year. Reoperations on the Bjork-Shiley prosthesis were performed in two patients for severe hemolysis, with an incidence of 0.32 per cent/patient-year. Reoperations on the St Jude Medical prosthesis were performed on 3 patients, for valve thrombosis in one patient, PVE in one, and hemolysis in one, with an incidence of 0.23 per cent/patient-year. The overall mortality rate was 20 per cent, or 7 patients, and the indications for reoperation affected this. Patients with primary tissue failure had a mortality rate of 10.3 per cent; those with a thrombosed valve, 0 per cent; those with hemolysis, 66.7 per cent; and those with valve infection, 100 per cent. A good chance of survival may be achieved in patients facing prosthetic valve complications by performing reoperation as soon as possible after early detection, since mortality is high following emergency reoperation and in patients with severe symptoms. Currently, we recommend mechanical prostheses for valve replacement except in patients over 70 years old and in younger patients with absolute contraindications to anticoagulative therapy.

[Intravascular hemolysis after prosthetic valve replacement]

Two kinds of mechanical valve, St. Jude Medical (SJM) and Björk-Shiley (B-S), in patients with single valve replacement have been evaluated on a view point of intravascular hemolysis. Cases were consisted of 78 SJM and 32 B-S for the mitral and 12 SJM and 36 B-S for the aortic positions. Serum LDH, indirect bilirubin, GOT, hemoglobin levels and reticulocyte count were pursued in a given schedule, especially on the 21st postoperative day. A follow-up study on cases with abnormally high level of LDH (over 800 W.U.) at the time of hospital discharge was also performed. Paravalvular leakage detectable on the echocardiographical study was denied in all cases. The case with SJM valve replacement on the mitral position revealed a higher level of LDH, GOT and a large count of reticulocyte than those in the B-S valve. Insignificantly was found, however, in the same study with replaced valve on the aortic position. There was no correlation between the severity of hemolysis and the size of prostheses. The level of LDH, remained in high on discharge declined gradually thereafter during postoperative observation. As a whole, the result of this study supports the conventional valve selection and usage in our clinic. The patient with subclinical hemolysis after valve replacement should be placed on a schedule of close observation.

Biochemical mechanisms of aminoglycoside cell toxicity. II. Accumulation of phospholipids during myeloid body formation and histological studies on myeloid bodies using twelve aminoglycoside antibiotics

Cultured human skin fibroblasts take up aminoglycoside antibiotics into lysosomes to form myeloid bodies. Gentamicin (GM), one such antibiotic, was taken up until the cellular concentration reached an estimated 64 mM on the 3rd day when cells were incubated with 2 mM gentamicin. The rate of release of intracellular GM was high on the first day of incubation and gradually slowed down over the next 4 d. About 50% of the GM remained in the cells even on longer incubation in GM-free medium, suggesting it may irreversibly bind to cellular components. With myeloid body formation, the cellular phospholipid content increased 1.5 times. Bis(monoacyl-glyceryl)phosphate, which is known as a marker of lysosomal phospholipid, phosphatidylcholine and phosphatidylserine showed 250, 162, and 153% increases, respectively. Sphingomyelin was not accumulated, while lysosomal sphingomyelinase was dramatically inhibited. Of 12 different aminoglycoside antibiotics, paromomycin is the most prominent myeloid body-forming antibiotic. The myeloid body-formation is not directly correlated to human nephrotoxicity. On the other hand, the number of myeloid bodies is well correlated to the affinity to the brush border membrane, suggesting that such aminoglycoside antibiotics are taken up easily through cellular endocytosis. The cytotoxic effects of aminoglycoside antibiotics may be due to by their binding to cellular organelles other than lysosomes.

Surgical treatment of the aged patient with patent ductus arteriosus

A 62-year-old woman with massively calcified patent ductus arteriosus (PDA) associated with severe pulmonary hypertension and bilateral hydronephrosis was successfully operated upon. At first, percutaneous nephrostomy was performed under ultrasonographic guidance. Two weeks later, PDA was repaired under cardiopulmonary (CP) bypass, since its division through a left thoracotomy was considered to be fraught with danger. A Foley's balloon catheter was inserted into the aorta through the ductus after a pulmonary arteriotomy under CP bypass. The ductus was closed simpler and safer with a patch mounted on the catheter, because blood flow from the aorta was well controlled by the inflated balloon catheter.