Expression of human soluble tissue factor in yeast and enzymatic properties of its complex with factor VIIa

The extracellular domain of human tissue factor (TF, amino acids 1-217) was expressed in Saccharomyces cerevisiae, using the inducible yeast acid phosphatase promoter and the yeast invertase signal sequence to direct its secretion into the culture broth. Two active soluble forms sTF alpha (high molecular weight form) and sTF beta (low molecular weight form) were purified, the yield being approximately 10 and 1 mg/liter of culture supernatant, respectively. sTF alpha had an apparent molecular mass of 150 kDa on SDS-polyacrylamide gel electrophoresis and contained more than 200 residues of mannose/mol of protein. sTF beta had an apparent molecular mass of 37 kDa and contained 22 residues of mannose/mol of protein. N-Glycosidase F treatments of both rTFs reduced the apparent molecular mass to 35 kDa. The amino-terminal sequences and amino acid compositions of sTF alpha and sTF beta were consistent with those deduced from the cDNA sequence, thereby indicating that the difference in molecular mass is caused by heterogeneity of oligosaccharide structures. Of these recombinant TFs, sTF beta enhanced factor VIIa-amidolytic activity 40-fold toward the chromogenic substrate and 147-fold toward the fluorogenic substrate, affecting mainly the kcat value. The enhancement was comparable with that of TF purified from human placenta. The TF-mediated enhancement of factor VIIa-amidolytic activity was inhibited by heparin-activated antithrombin III, forming a high molecular weight complex. As treatment of sTF beta with denaturants such as guanidine hydrochloride or urea led to a biphasic loss of the activity, the extracellular domain of TF probably consists of two discrete domains. This expression system provides a significant amount of the extracellular domain of TF so that studies of interactions with factor VII are feasible.

Dopamine decreases receptive field size of rod-driven horizontal cells in carp retina

Receptive field size of rod-driven horizontal cells (HCs) in the carp retina was measured by the spread of responses to the slit of light stimulus with changing the distance from the recording electrode and it was found to decay with a single exponential function. By perfusing 10 microM dopamine (DA) the length constant of rod-driven HCs was reduced to half and the response amplitude in the centre increased approximately two-fold, and the input resistance was markedly increased. This suggests that DA as a neuromodulator released from interplexiform cells could decouple the rod-driven HCs which had no direct synaptic contact with the interplexiform cells.

A multimicroelectrode system composed of independent glass micropipettes with an eccentric tip structure for simultaneous intracellular recording

A glass multimicroelectrode system for simultaneous intracellular recordings is described in which four pieces of micropipettes with rectangular cross section are arranged in a square compartment. Each tip position is shifted from the central axis of the electrode stem toward the crest line of its corner. Such micropipettes are mechanically bundled to one another so that the horizontal spacing among tips can be made shorter than the electrode diameter and components are independently penetrable. This paper offers techniques for fabricating such an eccentric micropipette. Finally, an example of simultaneous recordings of intracellular membrane potentials in the carp retina is demonstrated. This paper provides a technique which would allow researchers to record from three or four neurons simultaneously.

Urinary leukotriene E4 after exercise challenge in children with asthma

To assess the role of sulfidopeptide leukotrienes in the pathogenesis of exercise-induced asthma (EIA), the urinary levels of leukotriene E4 (LTE4), a metabolite of LTC4 and LTD4, were measured by RIA before and after exercise in 13 children with EIA and 10 healthy children. Mass spectrometry was used to confirm the presence of LTE4 in urine and the specificity of the RIA. There was no significant difference in the urinary LTE4 levels before exercise between the children with asthma and healthy children (109 [21 to 265] versus 122 [45 to 156] pg/mg of creatinine; median and range). Urinary LTE4 levels increased significantly after exercise in the children with EIA (from 109 [21 to 265] to 196 [40 to 655] pg/mg of creatinine; median and range; p less than 0.05) but not in the healthy children. The children with asthma demonstrated no significant correlation between the LTE4 level after exercise and the degree of bronchoconstriction, as revealed by the maximal percent fall in the peak expiratory flow rate. Taken together with a recent study that pretreatment with a potent and selective LTD4 antagonist markedly attenuated EIA, our findings suggest that sulfidopeptide leukotrienes may play some role in the pathogenesis of this type of asthma with other factors also being involved in determining the overall airway response.

A large conus artery in patients with hypertrophic cardiomyopathy

We retrospectively analyzed coronary arteriograms in 66 patients with hypertrophic cardiomyopathy (HCM) who underwent coronary arteriography. Four of these patients showed a large conus artery supplying the interventricular septum, and the characteristics of their echocardiograms revealed a marked interventricular septal hypertrophy. It is suggested that in some patients with HCM, the conus artery may develop in compensation for the relatively reduced coronary blood flow which is due to the hypertrophied myocardium.

Analysis of blood flow patterns in aortic aneurysm by cine magnetic resonance imaging--a review of case material

Cine magnetic resonance imaging (MRI) (0.5-T) using rephased gradient echo technique was performed in 5 normal volunteers and 14 patients with aortic aneurysm to study the patterns of blood flow in aortic aneurysm. In the transaxial section, blood flow in normal aorta appeared as homogeneous and high intensity during systole. Blood flow in aneurysm appeared as inhomogeneous flow enhancement with flow void. In the sagittal scan, the homogeneous flow enhancement in normal aorta was also observed during systole, and its apex of flow enhancement was "taper." The blood flow patterns in aneurysm were classified as "irregular," "zonal," "eddy," and "obscure," depending on the contrast of flow enhancement and flow void. Their apexes were "taper" or "round." When the size of aneurysm became larger, the flow pattern in aneurysm tended to become "eddy" or "obscure" and the flow enhancement became "round." Though the exact mechanism of abnormal flow patterns in aneurysm remains to be determined, cine MRI gives helpful information in assessing blood flow dynamics in aneurysm.

Fatal pulmonary hypertension in a patient with mixed connective tissue disease: report of an autopsy case

A 34-yr-old woman with mixed connective tissue disease (MCTD) who died of heart failure due to pulmonary hypertension (PH) is reported. She showed various symptoms and signs over the previous 8 yr, including lymphadenopathy, Raynaud's phenomenon, polyarthralgia, sclerodactylia, esophageal disturbance, PH, Sjögren's syndrome and renal tubular acidosis. Autopsy findings revealed severe intimal proliferation with marked luminal narrowing of the small arteries in the lung. Echocardiographic and mechanocardiographic methods were very useful for assessment of the degree of right ventricular dysfunction associated with PH on the early stage of MCTD.

Giant hydroureteronephrosis associated with primary obstructed megaureter

The case is presented of a four year old boy with a large left abdominal mass. The patient was diagnosed as having a left giant hydroureteronephrosis due to a primary obstructed megaureter, based on the findings of ultrasonography, micturating cystourethrography, excretion urography, computed tomography and percutaneous antegrade pyeloureterography. Diuretic renography showed that the obstruction was partial. Since a static renal scintigram indicated that renal function on the affected side was moderately well preserved, ureteroplasty is planned.

Influence of age and severity of hypertension on blood pressure response to isometric handgrip exercise

The influence of age and severity of hypertension on the blood pressure response to isometric handgrip exercise (IHG) was studied in essential hypertensive patients (n = 122). The change in blood pressure during IHG in elderly patients with isolated systolic hypertension (ISH) (n = 12) was also studied. Left ventricular hypertrophy due to hypertension was used as an index of the severity of hypertension. The change in systolic blood pressure (SBP) during IHG was markedly greater in essential hypertensives than in normotensive subjects (n = 36). Among hypertensive patients, the change in SBP increased with increasing severity of hypertension. This change in SBP was not influenced by age. The change in SBP during IHG in patients with ISH was significantly smaller than that in essential hypertensive patients and was similar to that in normotensive subjects in the elderly. These results demonstrate that age does not affect the increased blood pressure response to IHG in essential hypertensive patients but the greater the severity of hypertension, the greater the increase in SBP during IHG. Elderly patients with ISH do not have an enhanced blood pressure response to IHG.

Calcium and calmodulin regulate atrial natriuretic factor stimulation of cyclic GMP in a human renal cell line

We examined calcium and calmodulin regulation of atrial natriuretic factor stimulation of particulate-membrane guanylate cyclase (ANF-s-GC) in SK-NEP-1 cells. W7 and trifluoropiperazine, but not W5, inhibited whole cellular ANF-stimulated cyclic GMP accumulation (ANF-s-cGMP). EGTA and LaCl3 decreased ANF-s-GC and calmodulin reversed this inhibition. A23187-induced inhibition of ANF-s-cGMP was only partly reversible by IBMX. H7 or staurosporine counteracted the inhibitory effect of A23187. Calcium inhibited basal and ANF-s-GC. These data suggest that at low concentrations of calcium, ANF-s-GC was calcium-calmodulin dependent but high concentrations of calcium inhibited ANF-s-GC through phosphodiesterase, through inhibition of GC, and probably through protein kinase C.

Evaluation of lumbar bone mineral density by dual energy x-ray absorptiometry

Using dual-energy x-ray absorptiometry (DEXA), the lumbar spinal bone mineral density (BMD) in 49 Japanese children with or without metabolic bone disease (MBD) was determined. The following results were obtained: (a) The normal data for healthy Caucasians (J Clin Endocrinol Metab 1990; 70: 1330-1333) appear to be applicable to Japanese children; (b) BMD was normal in patients with congenital hydronephrosis with normal renal function; (c) One patient with congenital renal failure and one with Lowe syndrome had low BMD, but the MBD in the former improved markedly with peritoneal dialysis; (d) A reduced BMD was found in patients treated with long-term steroids, probably because of decreased turnover of bone; (e) A reduction in BMD was pronounced in preterm infants during the first few months of life. In conclusion, DEXA is a useful method of bone densitometry in MBD in children.

Mucopolysaccharidosis VI (Maroteaux-Lamy syndrome) with hearing impairment and pupillary membrane remnants

A Japanese boy aged 13 months was referred to us because thickened ribs had been observed on a chest X-ray taken during a respiratory infection. mucopolysaccharidosis type VI (MPS VI) was diagnosed based on urinary glycosaminoglycan analysis and low activity of arylsulfatase B in peripheral leukocytes. He had mild pupillary membrane remnants, but no corneal opacities. The auditory brainstem response revealed moderate hearing impairment, which may have caused his subnormal DQ score of 85 at the age of 19 months. Although MPS VI is characterized by normal intellectual development with normal hearing in early infancy, it is important to examine for hearing loss, especially when an infant with this disease shows developmental delay.

Pathophysiologic study on methylmalonic aciduria: decrease in liver high-energy phosphate after propionate loading in rats

Methylmalonate or propionate was i.v. infused into B12-deprived and control rats. In the B12-deprived rats, the plasma and liver concentrations of B12 decreased to 8 and 13%, respectively, of those of the control rats. The propionate loading produced a disproportionate increase in liver propionate levels; the mean ratio of methylmalonate to propionate in the liver was approximately 1.0 after methylmalonate loading, whereas it was 0.1 to 0.2 after propionate loading. The liver propionate and methylmalonate levels in the B12-deprived rats were twice as high as those in the control rats. The mean ratio of beta-ATP to inorganic phosphate in the liver, measured with 31P-magnetic resonance spectroscopy, decreased from 0.60 to 0.48 in the B12-deprived rats and from 0.78 to 0.63 in the control rats after methylmalonate loading; the ratio decreased from 0.57 to 0.37 in the B12-deprived rats and from 0.76 to 0.56 in the controls after propionate loading. Statistical analysis showed that propionate loading caused a more marked decrease in ATP than did methylmalonate loading (F = 26.33, degree of freedom 1 and 15; p less than 0.001), while B12-deprivation caused a more marked decrease in ATP than did the control diet (F = 92.26, df 1 and 15; p less than 0.001). The concentrations of tricarboxylic acid cycle intermediates and related organic acids in the livers of the rats suggested that propionate inhibited NAD(+)-dependent enzymes in the cycle.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of disopyramide on systolic and early diastolic time intervals in patients with hypertrophic cardiomyopathy

The present study clarified the effect of disopyramide on left-ventricular function in patients with hypertrophic cardiomyopathy (5 obstructive type: HOCM, 21 non-obstructive type: HNCM). The systolic and early diastolic time intervals were assessed 3 hours after a single oral administration of 100-mg disopyramide. The following parameters were evaluated at rest and after administration of disopyramide: 1) left-ventricular ejection time index (LVETI), 2) pre-ejection period index (PEPI), 3) the interval from aortic component of the second heart sound to mitral valve opening (IIA-MVO), and 4) the interval from MVO to O point of apexcardiogram (MVO-O). LVETI in HNCM did not change after disopyramide but that in HOCM was significantly shortened (P less than .05). PEPI in both HOCM and HNCM was significantly prolonged after administration of disopyramide. IIA-MVO time in both HOCM and HNCM was not influenced by disopyramide. MVO-O time in both HOCM and HNCM was significantly shortened after disopyramide. These results suggest that 1) shortening of LVETI in HOCM after disopyramide seemed to be due to the decrease in pressure gradient, 2) PEPI prolongation after disopyramide reflected the decrease in myocardial contractility, and 3) shortening of MVO-O time after disopyramide indicated the improvement of left-ventricular filling. The authors conclude that disopyramide may be an important new therapeutic agent in the treatment of patients with hypertrophic cardiomyopathy.

Familial primary pulmonary hypertension--report of two siblings

Familial primary pulmonary hypertension was found in two siblings (sister and brother). The woman noted exertional dyspnea at the age of 28 yr. The younger brother noticed exertional dyspnea, cough with bloody sputum and pretibial edema at the age of 38 yr. We diagnosed them as primary pulmonary hypertension as based on hemodynamic and histopathological findings. Regardless of the treatment, both patients died of right-sided heart failure with a short time course. We examined their family members, but there were no other members with primary pulmonary hypertension.

Exercise-induced urinary excretion of leukotriene E4 in children with atopic asthma

Urinary levels of leukotriene (LT) E4, a stable end-product of LTC4 and LTD4, were measured before and after exercise in 10 children with severe asthma and seven children with moderate asthma using HPLC and RIA to clarify the relationship of LT to the severity of asthma and to the degree of bronchospasm in exercise-induced asthma. The urinary LTE4 level significantly increased after exercise in the severe asthma group, but not in the moderate asthma group (14.3 +/- 14.5 to 24.3 +/- 20.6 versus 19.6 +/- 12.3 to 17.6 +/- 10.8 ng/mmol creatinine, p less than 0.05). The urinary LTE4 level increased in 10 patients (eight with severe asthma), and it decreased in seven patients (five with moderate asthma). A significant difference in the degree of bronchospasm after exercise (as shown by the maximal % fall in the peak expiratory flow rate), was seen when patients with increased urinary LTE4 excretion were compared with those with decreased excretion (60.4 +/- 17.3 versus 24.1 +/- 14.3%, p less than 0.01). Our findings suggest that exercise-induced asthma, or at least a subtype of exercise-induced asthma, may partly develop through the release of LTC4.

Scintigraphic assessment of cardiac adrenergic innervation in patients with essential hypertension

To assess the regional cardiac adrenergic innervation in patients with essential hypertension (EHT), simultaneous iodine-123 metaiodobenzylguanidine ([123I]MIBG) and thallium-201 (201Tl) myocardial imagings were performed in five patients with EHT, seven patients with hypertrophic cardiomyopathy (HCM), and seven normal subjects. Short axial images at rest were divided into five segments: anterior, septal, posterior, lateral, and apical segments. Percent regional uptake (%RU) of 201Tl except the septal segment in patients with EHT showed no significant difference. However, the %RU of [123I]MIBG at posterior, lateral, and apical segments was significantly lower than that at anterior and septal segments in EHT. This intraimage heterogeneity of [123I]MIBG was also observed in HCM. These results suggest that there is a difference in regional adrenergic innervation of the left ventricle with myocardial hypertrophy.

The development of personal computer-based medical consultation system for diagnosis of congenital malformation syndromes using MUMPS

This paper describes a medical consultation system for diagnosis of congenital malformation syndromes. The system consists of a personal computer, NEC PC-98XL (MS-DOS), using SP-MUMPS for the retrieval of knowledge data, and BASIC for the input/output of image data. This system displays pictorial knowledge and is designed so users can build up the knowledge base, as needed, by adding knowledge from medical literature and records of patients actually treated.

Diagnosis of iliopsoas pyomyositis by ultrasonography and CT

A patient with iliopsoas muscle pyomyositis was successfully treated with intravenous antibiotics alone. The diagnosis was made by ultrasonography and X-ray computed tomography after five days of spiking fevers. Ultrasonography and X-ray computed tomography revealed swelling of the muscle body but no abscess formation. We emphasize the usefulness of early diagnostic imaging to allow conservative treatment of iliopsoas muscle pyomyositis.

Leukotriene B4 production in children with steroid-responsive nephrotic syndrome

Leukotriene B4 (LTB4) production in polymorphonuclear leucocytes (PMN) was examined in ten children with steroid-responsive nephrotic syndrome (SRNS) before, during, and after steroid administration. Comparison of LTB4 production was made in 14 children with non-inflammatory disease who were not receiving steroid therapy. No significant change was noted in PMN LTB4 biosynthesis in children with SRNS throughout any phase of the disease. Furthermore, there was no significant difference in LTB4 biosynthesis in PMN between SRNS patients before steroid therapy and patients with non-inflammatory disease. These findings suggest that inhibition of LTB4 production is not involved in the mechanism underlying steroid action in SRNS.