Effects of inflorescence size on visits from pollinators and seed set of Corydalis ambigua (Papaveraceae)

Female reproductive success (seed set) of a spring ephemeral plant, Corydalis ambigua Cham. et schlecht (Papaveraceae) was investigated in relation to inflorescence size and foraging behavior (frequency and duration of visitations) by pollinators (namely, overwintered queens of Bombus hypocrita sapporensis) by detailed daily observations of a natural population. Pollination experiments indicated that C. ambigua is self-incompatible and that seed set was significantly affected by the behavior of the pollinating queens. Plants with larger inflorescences were visited more often than those with fewer flowers. Fecundity also increased with increasing size of inflorescences. Visitation time (duration of foraging) rather than the frequency of visitations (number of visits) was critical for higher fecundity. Seed production was strongly enhanced by a few long visits (of more than 60 s), and seemed to be independent of large numbers of short visits (of less than 60 s). Hence, plants with larger inflorescences, which provide a conspicuous signal to pollinators and offer greater rewards in terms of nectar, received longer visits by B. hypocrita sapporensis queens and those plants exhibited higher fecundity.

Mutation of a fungal aspartic proteinase, Mucor pusillus rennin, to decrease thermostability for use as a milk coagulant

Mutagenesis of a fungus Mucor pusillus, a producer of an aspartic proteinase named Mucor pusillus rennin (MPR), was performed to obtain the mutated enzymes with decreased thermostability, which is desirable for practical use of the enzyme as a milk coagulant for cheese manufacturing. A fungal mutant strain which produced the mutant enzyme with distinctly reduced thermostability was isolated. Two different mutant alleles of the mpr gene, one with a single amino acid exchange of Ala101 for Thr and the other of Gly186 for Asp, were cloned out of this mutant strain. The mutated mpr genes were expressed in Saccharomyces cerevisiae under the control of the yeast GAL7 promoter to produce the active enzymes in extracellular medium. Both of the mutations, especially Gly186Asp, were confirmed to cause a marked decrease in thermostability of the enzyme. All mutants possessing exchanges of Gly186 for various amino acids by site-directed mutagenesis showed a decrease in thermostability, indicating involvement of this residue to maintain a conformation of the enzyme. A double mutant having the both exchanges, Ala101Thr and Gly186Asp, in a single molecule showed the lowest thermostability without decrease in the enzymatic activity as well as the relative ratio of clotting to proteolytic activity.

Giant fusiform aneurysm at the horizontal portion of the middle cerebral artery in a child--case report

A 13-year-old boy with a rare giant fusiform aneurysm at the horizontal portion of the middle cerebral artery (M1) presented with progressively severe throbbing headache. The aneurysm was reconstructed by tandem application of nine fenestrated clips and coating of the remnant of the aneurysm. However, he was readmitted 3 months later because of recurrent aneurysms at the proximal and distal M1 portions which had been coated. The aneurysms were trapped after rupture occurred during a second operation. Aneurysm trapping combined with superficial temporal artery-middle cerebral artery bypass surgery may be a better method to treat such aneurysms.

[A case of coronary artery bypass grafting in a patient with active systemic lupus erythematosus]

A 59-year-old female was admitted to our hospital because of chest pain. Coronary angiography revealed severe obstruction of the left coronary artery. The findings of hematology and renal biopsy were interpreted as showing active systemic lupus erythematosus (SLE). Coronary artery bypass grafting was performed before steroid therapy because of worsening cardiac function due to myocardial ischemia. Postoperative course had been satisfactory immediately after operation, but the patient showed pulmonary infection about two months after operation and died three months after surgery. In open heart surgery for a patient with active SLE, special care must be taken to the prevention and treatment for infection.

Comparative SPECT study of stroke using Tc-99m ECD, I-123 IMP, and Tc-99m HMPAO

Brain perfusion SPECT imaging using Tc-99m ethyl cysteinate dimer (ECD) was carried out in 12 patients with chronic cerebrovascular disease. The sensitivity of lesion detection and lesion-to-normal tissue contrast was compared with those of I-123 IMP and Tc-99m HMPAO. Eight patients underwent all three studies and the remaining four patients had Tc-99m ECD and I-123 IMP scans. The sensitivity of lesion detection and lesion contrast was analyzed quantitatively using an asymmetric index determined by the equation: 100 x [right - left[/(right + left). In the cerebral cortex, cerebellum, and white matter, I-123 IMP showed higher lesion sensitivity than Tc-99m ECD and Tc-99m HMPAO. In the striatum and thalamus, Tc-99m ECD and I-123 IMP showed higher lesion sensitivity than Tc-99m HMPAO. I-123 IMP showed the highest lesion contrast in cerebral cortex and cerebellum, whereas Tc-99m ECD showed the highest contrast in thalamus and striatum. In all regions, Tc-99m ECD showed higher lesion contrast than Tc-99m HMPAO. These results suggest regional variation in the sensitivity of lesion detection and lesion contrast of Tc-99m ECD compared to I-123 IMP, and the superiority of Tc-99m ECD to Tc-99m HMPAO.

An in Vivo Study of Substrate Specificities of Acyl-Lipid Desaturases and Acyltransferases in Lipid Synthesis in Synechocystis PCC6803

The cyanobacterium Synechocystis PCC6803 was fed heptanoic acid to study the substrate specificities of desaturases and acyltransferases in lipid synthesis. This aliphatic acid was elongated to C15, C17, and C19 fatty acids, which were incorporated into polar glycerolipids and desaturated. The double bonds were located at the [delta]6, [delta]9, [delta]12, and [omega]3 positions of the fatty acids. This suggests that the [delta]9 desaturase counts the carbon number from the carboxy terminus, whereas the so-called [delta]15 desaturase counts from the methyl terminus. The counting mechanisms of the [delta]6 and [delta]12 desaturases are not fully understood. In the distribution of fatty acids at the sn positions of the glycerol moiety, the C17, C18, and C19 fatty acids were located at the sn-1 position, whereas the C15 and C16 fatty acids were located at the sn-2 position. This suggests that glycerol-3-phosphate acyltransferase specifically transfers heptadecanoic, octadecanoic, and nonadecanoic acids, whereas 1-acylglycerol-3-phosphate acyltransferase specifically transfers pentadecanoic and hexadecanoic acids.

Development of antitissue factor antibodies in patients after liver surgery

After liver surgery, two patients developed unexplainable prolonged prothrombin times (PT) that were not associated with bleeding tendency. The substitution of rabbit thromboplastin for either human or monkey thromboplastin in performing PT tests resulted in a normal clotting time. Tissue factor (TF) procoagulant activity assays and an immunoblotting analysis showed that these patients had developed IgG lambda-type immediate anticoagulants directed against both rabbit and bovine TF that did not crossreact with human or monkey TF. In a chromogenic assay, the patient IgG caused a decrease in both the Km and the Vmax of the factor X activation by rabbit TF-factor VIIa complex. The lack of reactivity of the patient IgG with human TF presumably explained why there was no clinical bleeding. Both patients had been treated earlier with a topical hemostatic agent prepared from bovine corium, microfibrillar collagen hemostat, while undergoing previous surgery. In an immunoblotting analysis, the patient IgG stained a 42-Kd band in the Triton extract of the collagen preparation under either reducing or nonreducing conditions. The Triton extract of the collagen preparation blocked the binding of the patient IgG to bovine TF. Thus, it is suggested that the iatrogenic immunization by intraoperative exposure of bovine TF retained in the collagen preparation may be responsible for the development of anti-TF antibodies in these patients. The anti-TF antibodies resulted in a clinical error in the evaluation of coagulation status after the use of rabbit thromboplastin.

[One-staged operation for funnel chest, mitral regurgitation and annulo-aortic ectasia associated of Marfan's syndrome]

One-staged operation was successfully performed in a 23-year-old female with funnel chest, mitral regurgitation and annulo aortic ectasia secondary to Marfan's syndrome. A midline skin incision was made and the sternum and costal cartilages were mobilized for sternal turnover with rectus muscles pedicle. This procedure offered an excellent operative field, even though the heart and aneurysmal ascending aorta were displaced into the left hemithorax. The combined superior-transseptal approach to the left atrium was used to perform mitral valve replacement. This approach also provided an excellent exposure of the mitral valve. Cabrol's operation was done for annulo aortic ectasia. Our concepts for the operation of open heart surgery complicated with severe funnel chest were discussed.

[CT finding of right diaphragmatic rupture due to blunt trauma--subhepatic hemothorax]

Owing to the poor detectability of the anatomic location of diaphragm on the parallel plane of computed tomography (CT), capability of CT to predict traumatic ruptured diaphragm has been debated in several reports. A specific hematoma (subhepatic hemothorax) adjacent to the posterior attachment of the right diaphragm was identified on CT. The finding originated from herniated liver that migrated to the posterior thoracic wall as a result of gravity, to separate the hemothorax in the supine position. This was surgically proven in two patients after blunt traumatic accident. The finding is useful in predicting right diaphragmatic rupture on CT study. The formation of subhepatic hemothorax, its differential diagnosis and a brief review of diaphragmatic rupture are discussed.

High resolution Tc-99m HMPAO SPECT in a patient with transient global amnesia

This is a report of a patient who underwent high-resolution brain perfusion SPECT studies during and after an episode of transient global amnesia. During the attack, SPECT imaging showed increased perfusion in the left medial temporal region involving the amygdala and hippocampus. After recovery from amnesia, a follow-up SPECT examination showed slightly decreased perfusion in this region. These findings support the hypothesis that transient global amnesia is associated with transient hyperperfusion in the medial temporal brain structures, and confirm the utility of high-resolution SPECT imaging for the evaluation of the fine details of functional brain anatomy.

Pharmacokinetics of (1R,2R-diaminocyclohexane)oxalatoplatinum(II) in comparison with cisplatin following a single intravenous injection in rabbits

The pharmacokinetics of (1R,2R-diaminocyclohexane)oxalatoplatinum(II) (1-OHP, NSC-266046), a second-generation antitumor platinum complex, was studied in rabbits and compared with that of cisplatin. The rabbits were given a single i.v. dose of 1-OHP or cisplatin (10 mumol/kg). A comparison of tissue platinum levels at 24 h postinjection showed that platinum levels were lower in the eight organs examined, which included the kidney and liver, after the injection of 1-OHP than following cisplatin administration. Plasma-decay profiles of three platinum species, that is, the unchanged species, filterable platinum, and total platinum, were examined. Plasma levels of the unchanged species and filterable platinum for 1-OHP declined more rapidly than those for cisplatin. The ratio of plasma filterable-to-total platinum indicated that the protein-binding ability of 1-OHP was greater than that of cisplatin. As for urinary excretion, amounts of the unchanged species and total platinum excreted during the 24 h period postinjection were 28% and 76% of the dose for 1-OHP and 23% and 57% of the dose for cisplatin, respectively. The renal clearance of both the unchanged species and filterable platinum in plasma for 1-OHP was about 2-fold that for cisplatin. 1-OHP is reported to be much less nephrotoxic than cisplatin. This may be due in part to its pharmacokinetic behavior or to pharmacokinetic differences resulting from chemical reactions that make 1-OHP less toxic than cisplatin.

Differential regulation of glucose transport and transporters by glucose in vascular endothelial and smooth muscle cells

Hyperglycemia has been implicated in the pathogenesis of both micro- and macrovascular complications in diabetes. Little is known, however, about glucose transporters and their regulation in the vascular system. In this study, the regulation of glucose transporters by glucose was examined in cultured BAECs and BSMCs, and in human arterial smooth muscle cells. Both BAECs and BSMCs transported glucose via the facilitated diffusion transport system. Glucose-transport activity in vascular smooth muscle cells was inversely and reversibly regulated by glucose. Exposure of BSMCs and HSMCs to high glucose decreased Vmax for 2DG and 3-O-MG uptake, whereas Km remained unchanged. The hexose-transport system of BAECs exhibited lower 2DG and 3-O-MG uptake compared with BSMCs and showed little or no adaptation to changes in ambient glucose. Northern blot analysis demonstrated that GLUT1 mRNA levels in BAECs and BSMCs were unaffected by the concentration of glucose in the medium. GLUT2-5 mRNA could not be detected by Northern blot analysis. GLUT1 protein, quantified by Western blot analysis, was more abundant in BSMCs than in BAECs and was decreased by approximately 50% when medium glucose was elevated from 1.2 to 22 mM for 24 h. The alterations in the level of GLUT1 protein correlated with the changes observed in transport activity. These observations suggest differential regulation of glucose transporter in response to glucose between smooth muscle and endothelial cells. The sites of autoregulation may involve translational control and/or the stability of the protein in the smooth muscle cells.(ABSTRACT TRUNCATED AT 250 WORDS)

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.

Cerebral arteriovenous malformations in a pregnancy with twins: case report

The natural course of cerebral arteriovenous malformations during pregnancy is not well known. An inoperable cerebral arteriovenous malformation was diagnosed by angiography, computed tomography, and magnetic resonance imaging before pregnancy and followed by magnetic resonance imaging during pregnancy. No significant changes were detected in the size of the cerebral arteriovenous malformation during pregnancy, and healthy twins were born by cesarean section.

Tissue factor potentiates the factor VIIa-catalyzed hydrolysis of an ester substrate

We designed a simple and sensitive method to assay the activity of the factor VIIa-tissue factor complex, using as a substrate N alpha-benzyloxycarbonyl-L-arginine p-nitrobenzyl ester (Z-Arg-ONb) (Zur, M., and Nemerson, Y. (1978) J. Biol. Chem. 253, 2203-2209). The principle was to measure the amount of p-nitrobenzyl alcohol released during ester hydrolysis using reversed-phase high performance liquid chromatography. Z-Arg-ONb had a broad specificity for plasma serine proteases and factor IXa. Using this method, we examined the effect of tissue factor on the esterase activity of factor VIIa under various conditions. We found that tissue factor greatly potentiates the factor VIIa-catalyzed hydrolysis of Z-Arg-ONb. Phospholipids were not required for the factor VIIa-catalyzed hydrolysis of Z-Arg-ONb, even in the presence of tissue factor. The Km value of factor VIIa alone toward the ester substrate was six times higher than that of a VIIa-tissue factor complex (3.2 versus 0.54 mM), whereas the kcat value was 12 times lower than that of the VIIa-tissue factor complex (14.3 versus 173 s-1). Thus, tissue factor apparently affects the catalytic site of factor VIIa and enhances hydrolysis of the ester substrate. This enhancing effect of tissue factor disappeared on removal of the gamma-carboxyglutamic acid domain from factor VIIa, whereas the esterase activity in the absence of tissue factor was not affected by this modification. The gamma-carboxyglutamic acid domain is probably required as a potent determinant for interactions with tissue factor, even in the absence of phospholipids in the reaction mixture.

[A case of encephalitis with MRI abnormalities localized in the bilateral amygdala and hippocampus]

We report a patient with encephalitis who showed anterograde and retrograde amnesia with MRI abnormalities localized in the bilateral amygdala (AM) and hippocampus (HIPP). A 25-year-old man suddenly experienced a generalized tonic-clonic seizure (GTCS). He was admitted because of increasing lethargy with two further GTCSs during the following 6 days. The patient had high fever, and neurological examination revealed somnolence, disorientation, amnesia, and nuchal stiffness. MRI revealed bilateral symmetrical abnormalities localized in the AM and HIPP, which showed low intensity on T1-weighted images and high intensity on T2-weighted images. Cerebrospinal fluid examination showed a mildly elevated cell count. We suspected herpes simplex virus type I encephalitis and began treatment with acyclovir. After the patient regained a clear consciousness, his antero- and retrograde amnesia continued for several months. The MRI abnormality became less distinct with the improvement of amnesia. We consider that the MRI abnormality was indicative of inflammation and edema, and that the lesion in the AM and HIPP had induced the amnesia.

Scanning electron microscopic observations of the periodontal ligament fibers and cells in rat molar teeth

The periodontal ligament of rat molar teeth was observed with scanning electron microscopy (SEM) using two different methods: NaOH maceration and KOH-collagenase treatments. Rat jaws with molar teeth were fixed, demineralized with 10% EDTA, and cut into several pieces. After maceration with 5% NaOH for 5 days at room temperature, the cellular elements were completely removed and the periodontal ligament fibers appeared as bundles of collagen fibrils. The fibers branched and anastomosed but did not spread fibrils randomly. In some regions near the alveolar bone, collagen fibrils circularly binding the fibers were found. When treated with 30% KOH for 7 to 10 minutes at 60 degrees C and with 0.1% collagenase, the periodontal ligament fibers were removed and the cells appeared as spindle and stellate shapes, and combined with the irregular cell processes of each other. Thus, the interaction between the periodontal ligament fibers and cells were three-dimensionally visualized by using the two different methods.

32P-postlabeling analysis of DNA adducts in rats during estrogen-induced hepatocarcinogenesis and effect of tamoxifen on DNA adduct level

DNA adduct formation in the liver, pancreas, kidneys and uterus in ethynylestradiol (EE)-induced carcinogenesis and the effect of tamoxifen (TAM) on DNA adduct formation were evaluated in female Wistar JCL rats using the 32P-postlabeling method. Hyperplastic nodules were noted in the liver of all rats 4 months after the first oral administration of 0.075 mg of EE, and hepatocellular carcinoma was detected in 8.1% of rats treated with EE for 12 months. DNA adducts increased in the liver for 4 months, reaching a level of 7.3 adducts/10(7) nucleotides and decreasing thereafter. Formation of DNA adducts was also noted in the pancreas and kidney, but the adduct levels were lower than those in the liver. TAM inhibited estrogen receptors (ER) in liver tissues and completely suppressed the development of hyperplastic nodules or hepatocellular carcinoma but did not affect DNA adduct formation in the liver. In this model, therefore, EE is considered to cause mutations of hepatocytes due to DNA adduct formation without mediation by ER and to induce initiated cells to develop into hepatocellular carcinoma in the presence of ER-mediated hormonal activities.

[67Ga scintigram and MRI in malignant bone tumors and malignant soft tissue tumors]

We have analyzed the characteristics of 67Ga scintigram and MRI in 11 malignant bone tumors and 11 malignant soft tissue tumors. Osteosarcoma showed a high accumulation in 67Ga scintigram and low signal intensity in T1 weighted image. T2 weighted image were not characteristic. Chondrosarcoma showed medium 67Ga accumulation and low signal in T1 weighted image and high signal in T2 weighted image. Ewing sarcoma showed low accumulation in 67Ga scan and medium intensity in MRI. Malignant soft tissue tumors showed rather low 67Ga accumulation compared with malignant bone tumors. Malignant fibrous histiocytoma showed medium accumulation of 67Ga, low signal in T1 weighted image and high signal in T2 weighted image. Liposarcoma showed low 67Ga accumulation and medium signal in T1 weighted image and high signal in T2 weighted image. To summarize these characteristics, three dimensional display is demonstrated.

[A case of SSPE presenting visual disturbance and serial MRI study]

A case of subacute sclerosing panencephalitis (SSPE) was reported. The patient was a 16-year-old boy and he initially developed visual disturbance. His neurologic symptoms were myoclonus, dementia, and visual disturbance which was rare as an initial symptom in SSPE. Fundoscopy revealed bilateral pole chorioretinitis and macular degeneration. Serial MRI study demonstrated the lesions in the brain and right eye ball. The distribution varied as time went on. T2-weighted MR images showed the lesions more clearly than T1-weighted MR images. In this case dementia was marked but the lesions in the cerebrum on the MR images were considerably smaller than expected. Although MR image is useful to show the lesions, the discrepancy between clinical signs and MR images may be present in the early stage in SSPE.

Hemifacial spasm associated with a cerebellopontine angle arachnoid cyst in a young adult

There are no reported cases of hemifacial spasm associated with an arachnoid cyst in the literature. We report the first case of hemifacial spasm with an ipsilateral cerebellopontine angle arachnoid cyst in a 25-year-old man. The patient underwent evacuation of the arachnoid cyst by a partial membranectomy without any beneficial effect, and finally got rid of the hemifacial spasm by reexploration and microvascular decompression of the facial nerve. The operative findings and results revealed that the cyst produced deviation of the ipsilateral posterior inferior cerebellar artery, which was secondarily in contact with the root exit zone of the facial nerve.

Laparoscopic varicocelectomy: a simple technique for clip ligation of the spermatic vessels

Less invasive laparoscopic surgery is replacing the conventional open operation for the treatment of several conditions. We performed laparoscopic clamping of the internal spermatic vessels in 12 subfertile patients to treat varicocele of the testis. Seven operations were performed with the patient under general anesthesia, whereas a local anesthetic was used in the 5 most recent patients. The internal spermatic vessels were successfully clipped in all 12 patients. Postoperative physical examination with a Doppler stethoscope showed that the venous reflux had disappeared in all patients. Semen quality was improved in 7 patients with a followup of 3 to 10 months. Neither hydrocele nor testicular atrophy was observed postoperatively. Laparoscopic varicocelectomy was effective and minimally invasive, especially when performed with the patient under local anesthesia.

Cerebral vasospasm with elevated creatine phosphokinase following surgery of unruptured arteriovenous malformation

Delayed cerebral vasospasm associated with marked elevation of serum creatine phosphokinase (CPK) is reported. A 21-year-old man with unruptured arteriovenous malformation (AVM) in the left temporal lobe developed postoperative symptomatic vasospasm lasting for 2 weeks. A postoperative computerized tomography scan showed intraventricular hematoma without subarachnoid hemorrhage in the basal cistern. On day 5 after surgery, the patient developed motor aphasia due to marked vasospasm around the bifurcation of internal carotid artery. On day 7 and 8, serum CPK was elevated as high as 1175 and 1376 IU/l, respectively. On day 35 when he had completely recovered from cerebral vasospasm both clinically and angiographically, the level of CPK was normalized. The causative factors of symptomatic cerebral vasospasm following surgery of unruptured AVM associated with CPK elevation are discussed.

Both the anaerobic pathway and aerobic desaturation are involved in the synthesis of unsaturated fatty acids in Vibrio sp. strain ABE-1

Vibrio sp. strain ABE-1 is a unique marine bacterium in terms of its ability to synthesize delta 9-trans-hexadecenoic acid and delta 7-cis-tetradecenoic acid (14:1(7c); Okuyama, H., Sasaki, S., Higashi, S. and Murata, N. (1990) J. Bacteriol. 172, 3515-3518). The present study, involving labeling with [1-14C]acetate, demonstrated that 14:1 is synthesized by the anaerobic pathway. When cells of this bacterium were grown in the presence of [1-14C]myristic acid (14:0), this compound was converted to palmitic (16:0) and hexadecenoic (16:1) acids but not to 14:1, under aerobic conditions. These results suggest that the incorporated 14:0 was elongated to 16:0 and then converted to 16:1 by the aerobic desaturation of 16:0. It appears that the anaerobic pathway and aerobic desaturation are both involved in the synthesis of unsaturated fatty acids during aerobic growth of Vibrio sp. strain ABE-1.