Comparative studies of thrombolysis with single-chain and two-chain recombinant tissue-type plasminogen activators in canine coronary thrombosis

Tissue-type plasminogen activator (t-PA) can occur in two different forms, single- and two-chain t-PA. Such a difference in structure of the t-PA molecule may induce different biological functions. We compared the thrombolytic efficacy of single-chain t-PA with that of two-chain t-PA and urokinase in a canine thrombosis model. The thrombolytic properties of single- and two-chain recombinant t-PA and urokinase with equivalent activity in vitro after intravenous infusion were examined in 24 anesthetized, open-chest dogs with intracoronary thrombi. Repeated coronary angiography showed that the time to reperfusion was 29.0 +/- 4.8, 32.5 +/- 6.3, and 39.2 +/- 6.8 min, respectively. One dog in the single-chain t-PA group and all dogs in the vehicle group showed no recanalization. Plasma t-PA antigen reached similar plateau levels within 15. min in both the single- and two-chain t-PA groups. The infusion of single- and two-chain t-PA was not associated with systemic fibrinolytic activation, except for a decrease in alpha 2-plasmin inhibitor in single-chain t-PA. However, the infusion of urokinase was associated with significant depletion of fibrinogen. These findings suggest that single-chain t-PA has potent thrombolytic effect without systemic fibrinolytic activity similar to that of two-chain t-PA in a canine coronary artery thrombosis model.

[The quantitative regional cerebral blood flow measurement with autoradiography method using 123I-IMP SPECT: evaluation of arterialized venous blood sampling as a substitute for arterial blood sampling]

The purpose of this study is validation of calibrating a standard input function in autoradiography (ARG) method by one point venous blood sampling as a substitute for that by one point arterial blood sampling. Ten and 20 minutes after intravenous constant infusion of 123I-IMP, arterialized venous blood sampling from a dorsal vein were performed on 15 patients having ischemic cerebrovascular disease. And arterial blood sampling from radial artery was performed 10 min after 123I-IMP infusion. The mean difference rates of integrated input function between calibrated standard input function by arterial blood sampling at 10 min and that by venous blood sampling were 4.1 +/- 3% and 9.3 +/- 5.4% at 10 and 20 min after 123I-IMP infusion, respectively. The ratio of venous blood radioactivity to arterial blood radioactivity at 10 min after 123I-IMP infusion was 0.96 +/- 0.02. There was an excellent correlation between ARG method CBF values obtained by arterial blood sampling at 10 min and those obtained by arterialized venous blood sampling at 10 min. In conclusion, a substitution by arterialized venous blood sampling from dorsal hand vein for artery can be possible. The optimized time for arterialized venous blood sampling was 10 min after 123I-IMP infusion.

[Reye syndrome evaluated by 99mTc-ECD SPECT: a case report]

We report a three-year-old boy with Reye syndrome evaluated by 99mTc-ECD SPECT. On acute stage, 99mTc-ECD brain SPECT disclosed diffuse high uptake in the cerebral cortex in spite of normal findings on brain X-ray CT. These lesions changed to general low uptake on the chronic state and multiple high intensity areas were shown on T2 weighted MRI image. Such a change of cerebral tracer uptake was considered to reflect the neuropathological change of Reye syndrome. 99mTc-ECD SPECT was a useful modality to diagnose Reye syndrome complementary.

Oxygen-dependent reversible inhibition of mitochondrial respiration by nitric oxide

Effects of nitric oxide (NO) and NO generating agents, on the electron transport system of mitochondria were examined in a study of the mechanism and physiological importance of NO in energy metabolism. In the presence of various substrates, uncoupled respiration was inhibited by NO in manner which was both dose- and oxygen tension-dependent. Simultaneously measuring changes in cytochrome absorption spectra and respiration showed that the site of action of NO is cytochrome oxidase. Similar inhibition was also brought about by 1-hydroxy-2-oxo-3,3-bis(2-aminoethyl)-1-triazene (NOC 18), an NO donor. Electron paramagnetic resonance (EPR) analysis revealed that inhibition of uncoupled respiration occurred only during the presence of NO in the reaction mixture. The inhibitory effect of NO was increased significantly by lowering the concentration of mitochondrial protein. No appreciable inhibition of respiration was observed in the presence of 3-morpholinosydnonimine (SIN-1), a peroxynitrite anion (ONOO-) generating reagent, but inhibition did occur in the presence of superoxide dismutase (SOD). These results indicate that NO reversibly interacts with mitochondria at complex IV thereby inhibiting respiration particularly under physiologically low oxygen tension and that de novo generated ONOO may have no significant effect under the present experimental conditions.

123I-MIBG myocardial scintigraphy in diabetic patients: relationship to autonomic neuropathy

The aim of this study was to investigate the relationship between autonomic nerve dysfunction and myocardial uptake of 123I-meta-iodobenzyl guanidine (MIBG) in patients with diabetes mellitus. Twenty-two non-insulin-dependent diabetic patients, 9 with autonomic neuropathy [ANP(+)] and 13 without autonomic neuropathy [ANP(-)], and 8 controls were included in the study. Both planar and single photon emission tomographic (SPET) images were obtained 30 min (early) and 3 h (delayed) after the 123I-MIBG injection. The heart-to-mediastinal uptake ratio (H/M) and the washout ratio of 123I-MIBG (%WR) were calculated from planar images. The uptake ratio of the inferior wall to the anterior wall (I/ A) and the %WR of both the inferior and anterior walls were calculated from the SPET images. On the early plantar images, the mean H/M ratio in the ANP(+) group was significantly lower than that of the control group. The mean %WR on the planar images in the ANP(-) group was significantly higher than that of the controls. The SPET images demonstrated a reduction in MIBG uptake and significantly increased clearance in the inferior wall of the ANP(-) patients. These findings extended to other areas of the heart in the ANP(+) patients. In the quantitative analysis of the SPET images, the ANP(+) group had significantly lower I/A values and significantly higher %WR values in the anterior wall. The ANP(+) group showed significantly increased clearance of 123I-MIBG in the inferior wall. We conclude that 123I-MIBG myocardial scintigraphy is a useful diagnostic tool both in the early detection and evaluation of the progression of myocardial sympathetic nerve dysfunction in patients with diabetes mellitus. Both the I/A and %WR calculated from SPET images are useful parameters.

Technetium-99m-sestamibi scintigraphy compared with thallium-201 in evaluation of thyroid tumors

Technetium-99m methoxyisobutylisonitrile (MIBI) is a myocardial perfusion imaging agent that has been reported to effectively localize in various tumors (e.g., lung and thyroid carcinomas and osteogenic sarcoma). To determine its usefulness in thyroid tumors, we compared 99mTc-MIBI with 201TI imaging.

METHOD

We evaluated 25 patients with thyroid tumors (papillary carcinoma in 11, follicular carcinoma in 2, follicular adenoma in 7, adenomatous goiter in 5). Fifteen metastatic lesions from differentiated thyroid carcinomas were also evaluated. Early (10 min after injection) and delayed images (120 min after injection) were obtained for both 99mTc-MIBI and 201TI scintigraphy.

RESULTS

The early images showed very similar findings for both 99mTc-MIBI and 201TI. However, the delayed images showed that malignant tumors tended to retain more tracer agent than benign nodules. Marked retention was in 61.5% (8 of 13) of 201TI images and 53.8% (7 of 13) of 99mTc-MIBI images. For metastatic lesions from thyroid carcinomas, the findings for 99mTc-MIBI imaging were nearly identical to those for 201TI imaging. A slight difference in clarity was seen that may have been due to the effect of the 99mTc.

CONCLUSION

Although 99mTc-MIBI scintigraphy does not have particularly good results in differentiating malignant from benign thyroid tumors, it may be useful in evaluating metastases or predicting recurrence because of its better imaging characteristics.

YM-47522, a novel antifungal antibiotic produced by Bacillus sp. II. Structure and relative stereochemistry

YM-47522 (1) was isolated from the fermentation broth of Bacillus sp. YL-03709B as an antifungal antibiotic. The structure of 1 was elucidated by spectroscopic analyses. YM-47522 (1) consisted of C13 carboxylic acid amide and cinnamate moieties. The relative stereochemistry was also proposed on the basis of chemical transformation into a 1,3-diol acetonide and its NMR data.

Aspects of carbonic anhydrase and carbonate content during mineralization of the rat enamel

We examined carbonic anhydrase and carbonate content in developing dental enamel to clarify some problems in connection with the initial mineralization. Two-dimensional electrophoretic analysis showed that the type of carbonic anhydrase isoenzyme in developing enamel tissue was a low-activity form. A relatively high activity of carbonic anhydrase was detected in the developing enamel of rat lower incisors. We also determined that the content rate of carbonic anhydrase accounts for about 4% of the total matrix proteins of early developing enamel. A remarkable reduction of carbonic anhydrase activity occurred at the maturation stage, and then disappeared in the fully matured enamel. The carbonate content also decreased gradually, showing a parallel profile to that of carbonic anhydrase activity, from 3.5% to 1.9% in mineral phase. From the present study, we proposed that carbonic anhydrase in the initial site of mineralization may act as a trigger for the crystal nucleation by supplying the carbonate ions into the precursor mineral at the early stage of crystal development.

201TL SPECT for evaluating head and neck cancer

BACKGROUND

Thallium-201 (201Tl) has come to be widely used in diagnosis of several kinds of malignant tumor, but its usefulness in diagnosing head and neck cancer has not been established.

PURPOSE

This study investigated the usefulness of 201Tl SPECT imaging in patients with head and neck cancer histologically confirmed.

METHODS

Eighteen patients with histologically proven head and neck cancer were studied. 201Tl SPECT images were obtained both 15 min and 4 hours after intravenous injection of 148 MBq of 201Tl-chloride. 201Tl-indices were calculated semiquantitatively to assess the tracer uptake in relation to tumor size and histological type.

RESULTS

High 201Tl uptake was noted in all primary tumors and metastatic lymph nodes on the both early and delayed images, but 201Tl-indices did not show any correlation with tumor size or histological type.

CONCLUSION

Primary had and neck cancer and lymph node metastasis can be effectively visualized with 201Tl SPECT. It may provide information in addition to morphological changes and may be supplemental method to use in the evaluation of head and neck cancer.

Lipoteichoic acid-induced neutrophil adhesion via E-selectin to human umbilical vein endothelial cells (HUVECs)

We investigated whether lipoteichoic acid (LTA) induces the expression of E-selectin and neutrophil adhesion to human umbilical vein endothelial cells (HUVECs). LTA (0.01-30 micrograms/ml) induced the expression of E-selectin in a concentration-dependent manner with maximal response at 10 micrograms/ml. The expression level of E-selectin increased from 2 h after stimulation by LTA with the maximal level at 4-8 h. Neutrophil adhesion to LTA-treated HUVECs correlated with the levels of E-selectin expression. In addition, the adhesion was clearly inhibited by anti-human E-selectin monoclonal antibody CY-1787 as well as a sialyl Lewis X (SLeX) oligosaccharide. LTA-induced expression of E-selectin was inhibited by protein kinase C inhibitors, H-7 and staurosporine. These results indicate that LTA induced the expression of E-selectin and neutrophils adhered to HUVECs via E-selectin.

Simultaneous malignant melanoma and squamous cell carcinoma of the oral cavity: a case report

Primary malignant melanoma of the oral cavity is rare. The incidence of oral melanoma constitutes between 0.2% and 8.0% of all melanomas, although higher percentages are reported in Japanese and other nonwhite races. In contrast, squamous cell carcinoma is the most common malignant neoplasm in the oral region. Multiple cancers may develop independently over the course of time in one organ, or double cancers may develop separately in different organs. Both types of cancer are collectively referred to as multiple primary cancers. The simultaneous occurrence of two histologically distinct primary malignancies in the same organ is extremely rare. We present a case of simultaneous malignant melanoma in association with squamous cell carcinoma of the oral cavity.

[The effect of sodium fluoride on bone mineral density and bone strength in ovariectomized rats]

An experimental study was performed to evaluate the effects of sodium fluoride (NaF) on bone mineral density (BMD) and bone strength in rat. Sixty-nine female Wistar rats aged 12 months were used. Ovariectomy was carried out in 59 rats, and 3 of these were sacrificed to confirm osteopenia at 6 months after the ovariectomy. Twenty-eight of the remaining 56 rats were given NaF. Half of this NaF Group was given high-Ca feed and the other half was given normal feed. And one half of the High-Ca Group and one half of the Normal Feed Group were given vit. D. The other 28 rats in the Non-NaF Group were given high-Ca and vit. D as in the NaF Group. Accordingly, eight groups were created, each with seven rats. All were treated for 9 weeks. An additional 10 rats were used for control. At 6 months after a sham operation, three of these controls were sacrificed to confirm non-osteopenia. The remaining seven controls were given normal feed for 9 weeks. Therefore, there was total of 9 groups (69 rats). At eight months after the surgery (ovariectomy or the sham procedure), both femurs were removed from each rat. The BMD was measured over the entire femur by the DXA method. Bone strength was measured by three-point bending, compression and penetration tests. BMD was found to be higher in the NaF Group than in the Non-NaF Group or Control Group, and was highest in the NaF-high-Ca feed Group. In the bone strength test, the NaF Group scored higher than the Non-NaF Group. In the three-point bending and penetration tests, the NaF-high-Ca feed Group was highest. A linear correlation was found between the BMD and bone strength. There was no effect produced by the administration of the vit. D on the BMD or bone strength. In conclusion, the experimental administration of NaF, and of high-Ca feed, increased BMD and bone strength.

Graves ophthalmopathy: MR evaluation of 10-Gy versus 24-Gy irradiation combined with systemic corticosteroids

PURPOSE

To establish the most effective radiation dose for treatment of Graves ophthalmopathy (GO).

MATERIALS AND METHODS

A combination of 10 Gy (n = 15) or 24 Gy (n = 16) of radiation and corticosteroids was used to treat 31 patients with GO. Magnetic resonance (MR) images obtained before treatment showed swollen extraocular muscles with prolonged T2 relaxation times in all patients.

RESULTS

Before therapy, T2 relaxation time of extraocular muscle was 79.6 msec (95% confidence interval, 76.3, 82.9) in the 24-Gy group and 77.4 msec (95% confidence interval, 74.6, 80.1) in the 10-Gy group (P = .32). After therapy, T2 relaxation time was 62.8 msec (95% confidence interval, 61.2, 64.4) in the 24-Gy group and 68.9 msec (95% confidence interval, 66.8, 71.1) in the 10-Gy group. In the 24-Gy group, there was a significant decrease in T2 relaxation times (P = .001) and clinical response to initial treatment was better. At 1- and 3-month follow-up, the resistance rate was lower in the 24-Gy group.

CONCLUSION

In treatment of GO, 24 Gy of radiation is a more effective dose than 10 Gy when combined with systemic corticosteroids.

Ultrastructure and x-ray microanalytical study of human pineal concretions

We examined human pineal concretions and found them to exhibit a multi-layered concentric structure consisting of irregularly spaced dense and sparse zones containing fine crystals. The hydroxyapatite crystallites were shown to be irregularly outlined plate forms (measuring 11-70 nm in their longest dimension and 2-10 nm in thickness). At the center of each crystallite a central dark line was observed by means of high resolution electron microscopy. The structure and size of the crystals were similar to those of dentin and bone. The ground surface of the concretions was observed metallurgically by means of an electron probe microanalyzer (EPMA). The surface zones of the concretions contained a higher concentration of zinc, which seems to play an important role during the mineralization process, whereas calcium and phosphorus exhibited higher concentrations at the center.

In vivo biological behavior of a water-miscible fullerene: 14C labeling, absorption, distribution, excretion and acute toxicity

BACKGROUND

Water-soluble fullerenes have recently been shown to exhibit considerable in vitro biological activity including cytotoxicity, site-selective DNA cleavage and inhibition of HIV protease. To assess the potential of these compounds as drugs, studies on the in vivo behavior of fullerenes are needed. We therefore set out to synthesize a radiolabeled, water-soluble fullerene, in order to obtain data on the oral absorption, distribution and excretion of this class of compounds.

RESULTS

We synthesized a 14C-labeled water-soluble [60]fullerene using dipolar trimethylenemethane, which undergoes cycloaddition to [60]fullerene. When administered orally to rats, this compound was not efficiently absorbed and was excreted primarily in the feces. When injected intravenously, however, it was distributed rapidly to various tissues, and most of the material was retained in the body after one week. The compound was also able to penetrate the blood-brain barrier. Acute toxicity of the water-miscible fullerene was found to be quite low.

CONCLUSIONS

Although the water-soluble fullerenes (and possibly their simple metabolites) are not acutely toxic, they are retained in the body for long periods, raising concerns about chronic toxic effects. The fact that fullerenes distribute rapidly to many tissues suggests that they may eventually be useful to deliver highly polar drugs through membranes to a target tissue, however, and they may even have applications in the delivery of drugs to the brain. Recent advances in fullerene synthetic chemistry may also make it possible to control fullerene absorption/excretion profiles in the future.

Regulation of proliferation and osteochondrogenic differentiation of periosteum-derived cells by transforming growth factor-beta and basic fibroblast growth factor

We studied the effects of transforming growth factor-beta and basic fibroblast growth factor on the regulation of proliferation and osteochondrogenic differentiation of periosteum-derived cells, which have the potential to differentiate into bone and hypertrophic cartilage in vitro. Histological observation revealed that transforming growth factor-beta stimulated chondrogenesis of periosteum-derived cells while basic fibroblast growth factor stimulated proliferation of fibroblast-like cells and inhibited osteochondrogenic differentiation. Immunohistochemical studies revealed that basic fibroblast growth factor inhibited the expression of osteocalcin. Transforming growth factor-beta enhanced uronic acid content but decreased DNA content, alkaline phosphatase activity, and calcium content. In contrast, basic fibroblast growth factor enhanced DNA content but decreased alkaline phosphatase activity, calcium content, and uronic acid content. In addition, transforming growth factor-beta shortened the time-course of gene expression of type-X collagen whereas basic fibroblast growth factor inhibited the gene expression. These results indicate that transforming growth factor-beta stimulates osteochondrogenic differentiation of periosteum-derived cells but inhibits proliferation. They also indicate that basic fibroblast growth factor stimulates proliferation of periosteum-derived cells but inhibits osteochondrogenic differentiation.

[Scimitar syndrome with diagnostic MRI findings]

A fifty-year-old woman was admitted to our hospital because of an abnormal shadow on a chest X-ray film. She was asymptomatic. Chest X-ray film showed a scimitar-like vessel in the right lung, dextroposition of the heart, and hypoplasia of the right pulmonary artery. MRI revealed that the scimitar vein was anomalous pulmonary venous return from the right lung. Normal venous return from the right lower lobe to the left atrium was confirmed by pulmonary artery angiography. MRI findings have been useful in the diagnosis of scimitar syndrome.

[A case of traumatic aneurysm of the thoracic aorta with severe chronic compression of the trachea]

A case of successfully treated traumatic aneurysm of the thoracic aorta with severe major air way compression was reported. A 38-year-old man, who had a history of blunt chest trauma in a traffic accident twenty years ago, complained of asthma-like coughing chest CT scan and angiogram showed a saccular aneurysm of desending aorta compressing the isthmus of the trachea and the esophagus severely. Resection of the aneurysm and prosthetic graft replacement was undertaken successfully with the aid of F-F bypass. The trachea and the esophagus were well decompressed and the patient recovered well with no complaints.

Prognostic significance of posterior subtalar joint arthrography following fractures of the calcaneus

Nineteen patients with 22 intra-articular fractures of the calcaneus were investigated by posterior subtalar joint arthrography after 6 (2-15) months following injury, and their clinical symptoms were compared with the arthrographic findings. The arthrograms were classified into four types based on the findings of the joint space of the posterior subtalar joint in Anthonsen's view. The classification correlated significantly (P = 0.03) with the clinical results which were assessed after 23 (9-41) months following injury. We conclude that posterior subtalar joint arthrography has prognostic value in assessing patients with fractures of the calcaneus.

Auxiliary heterotopic partial liver transplantation in pigs with acute liver failure

Fulminant hepatic failure is usually fatal without liver transplantation; however, orthotopic liver transportation is often difficult to perform due to the high risk of coagulopathy and the development of multiple organ failure. Auxiliary heterotopic partial liver transplantation (APLT), However, has the potential to provide an effective hepatic support system considering that the host liver is left in situ and the surgical procedure is less invasive. In this report, we describe the beneficial effects of performing 60% APLT on the hepatic function and survival of pigs with acute hepatic failure induced by hepatic artery ligation. The pigs were divided into a control group of nine animals (group 1) that had portal vein and hepatic artery ligation with a side-to-side portacaval shunt, and an APLT group of seven animals (group 2) that had portal vein and hepatic artery ligation with APLT. The two left lateral lobes of the donor liver were resected, reducing the liver weight to about 60%, and the graft was placed in the right subhepatic space. No deaths occurred intraoperatively. In group 1, eight pigs died of massive liver necrosis within 48 h and one died between 48 and 72 h (median survival 23 h). In group 2, two pigs died within 72 h due to preservation or anesthetic problems, but five survived for more than 3 days (median survival 13.4 days), with a significant difference between the two groups (P < 0.05). One animal was killed 30 days after APLT and excellent graft function was demonstrated by the synthesis of clotting factors, ammonia detoxification, and glucohomeostasis. Moreover, evidence of hepatic regeneration was found in the transplanted livers.(ABSTRACT TRUNCATED AT 250 WORDS)

[Analysis of lipopolysaccharide (LPS) from impermeability-type drug resistant Pseudomonas aeruginosa using new, highly-sensitive LPS staining method]

The specific ladder pattern on polyacrylamide gel electropholesis of lipopolysaccharide (LPS) extracted from Pseudomonas aeruginosa was clearly shown by using the complex methods of the PAS staining, re-periodate oxidation and then Ag-staining method. Accordingly, it was concluded that the new method was greatly useful for a detail analysis of LPS changes in Gram-negative bacteria. And it was shown by this method that no changes in LPS occurred between the impermeability-type drug resistant P. aeruginosa mediated by R plasmid and a drug susceptible strain. The absence of changes indicated that the LPS of P. aeruginosa K-Ps102 had not role in the mechanism of the high drug resistance.