In vivo recognition of mannosylated proteins by hepatic mannose receptors and mannan-binding protein

In vivo recognition of mannosylated proteins by hepatic mannose receptors and serum mannan-binding protein (MBP) was investigated in mice. After intravenous administration, all three different (111)In-mannosylated proteins were taken up mainly by liver, and uptake was saturated with increasing doses. (111)In-Man-superoxide dismutases and (111)In-Man(12)- and (111)In-Man(16)-BSA had simple dose-dependent pharmacokinetic profiles, whereas other derivatives ((111)In-Man(25)-, -Man(35)-, and -Man(46)-BSA and (111)In-Man-IgGs) showed slow hepatic uptake at <1 mg/kg. Purified MBP experiments in vitro indicated that these derivatives bind to MBP in serum after injection, which interferes with their hepatic uptake. To quantitatively evaluate these recognition properties in vivo, a pharmacokinetic model-based analysis was performed for (111)In-Man-BSAs, estimating some parameters, including the Michaelis-Menten constant of the hepatic uptake and the dissociation constant of MBP, which correlate to the affinity of Man-BSAs for mannose receptors and MBP, respectively. The dissociation constant of Man-BSA and MBP decreased dramatically with increasing density of mannose, but the Michaelis-Menten constant of hepatic uptake of Man-BSA was not so sensitive to the change in density. This suggests that the in vivo recognition of MBP has a stronger cluster effect than that of mannose receptors. Differences obtained here are due to the unique arrangement of carbohydrate recognition domains on each mannose-specific lectin available for mannosylated ligand recognition.

[Comparative studies on activities of antimicrobial agents against causative organisms isolated from patients with urinary tract infections (1999). I. Susceptibility distribution]

The bacterial strains isolated from patients diagnosed as having urinary tract infections (UTIs) in 9 institutions in Japan were supplied between the period of August 1999 to July 2000. Then, the susceptibilities of them to many kinds of antimicrobial agents were investigated. The number of them were 499 strains. The breakdown of these strains was Gram-positive bacteria as 31.3% and Gram-negative bacteria as 68.7%. Susceptibilities of these bacteria to antimicrobial agents were as follows; vancomycin (VCM), ampicillin (ABPC) and imipenem (IPM) showed strong activities against Enterococcus faecalis. The increase of low-susceptible strains which was noticed in the former year showed a slight recovery in this year. VCM showed a strong activity against MRSA preventing growth of all strains with 1 microgram/ml. In addition, the activity of arbekacin (ABK) was also strong with the MIC90 of 2 micrograms/ml against MRSA. However, MSSA and MRSA showing low susceptibilities were detected in one strain each (MIC: 16 micrograms/ml and 32 micrograms/ml, respectively). Carbapenems showed high activities against Citrobacter freundii and Escherichia coli. Meropenem (MEPM) prevented growth of all strains within 0.125 microgram/ml. Quinolone resistant E. coli decreased in this year compared with those in the last year, that percentage was less than 5%. Almost all drugs showed strong activities against Klebsiella pneumoniae and Proteus mirabilis. MEPM and carumonam (CRMN) prevented growth of all strains within 0.125 microgram/ml. On the other hand, one strain of K. pneumoniae showing resistance to cefaclor (CCL) and one strain of P. mirabilis showing low susceptibility to most of cephems were detected. Against Pseudomonas aeruginosa, almost drugs were not so active. The MIC90s of carbapenems were 8 micrograms/ml and those of all other drugs were more than 16 micrograms/ml.

Incidence of amantadine-resistant influenza A viruses in sentinel surveillance sites and nursing homes in Niigata, Japan

We surveyed the incidence of amantadine-resistant influenza A viruses both at sentinel surveillance sites and at nursing homes, and verified their types of change by partial nucleotide sequence analysis of the M2 protein. Fifty-five influenza A viruses from 27 sentinel surveillance sites during six influenza seasons from 1993 to 1999, and 26 influenza A viruses from 5 nursing homes from 1996 to 1999 were examined for susceptibility to the drug by virus titration in the presence or absence of amantadine. While amantadine-resistant viruses were not found in sentinel surveillance sites, a high frequency of resistance (8/26, 30.8%) in nursing homes was observed. Resistant viruses can occur quickly and be transmitted when used in an outbreak situation at nursing homes, where amantadine is used either for neurologic indications or for influenza treatment. Eight resistant viruses had a single amino acid change of the M2 protein at residue 30 or 31. In vitro, all 11 sensitive viruses turned resistant after 3 or 5 passages in the presence of 2 microg/ml amantadine, and they showed an amino acid change at residue 27, 30, or 31. The predominant amino acid substitution in the M2 protein of resistant viruses is Ser-31-Asp (a change at 31, serine to asparagine). The results indicate that a monitoring system for amantadine-resistant influenza viruses should be established without delay in Japan.

Development of gene drug delivery systems based on pharmacokinetic studies

A series of pharmacokinetic studies following systemic or local administration for the development of delivery systems for gene drugs, such as plasmid DNA and oligonucleotides, are reviewed. The pharmacokinetics of gene drugs after intravenous injection into mice was evaluated based on clearance concepts. Pharmacokinetic analysis revealed that the overall disposition characteristics of the gene drug itself were determined by the physicochemical properties of its polyanionic DNA. Based on these findings, liver cell-specific carrier systems via receptor-mediated endocytosis were successfully developed by optimizing physicochemical characteristics. On the other hand, the pharmacokinetics of gene drugs after intratumoral injection were assessed in a tissue-isolated tumor perfusion system. The relationship between the physicochemical properties of gene drug delivery systems and intratumoral pharmacokinetics was determined and the therapeutic effect was also discussed in relation to pharmacokinetics. Collectively, it was demonstrated that a rational design of gene drug delivery systems that can control their in vivo disposition is possible by means of pharmacokinetic studies at whole body, organ and cellular levels.

Effects of diversion and reperfusion of pancreaticobiliary juice on amylase release from isolated rat pancreas

Diversion of pancreaticobiliary juice from the small intestine results in resetting of the normal negative-feedback regulation of exocrine pancreatic secretion. The mechanism by which this process occurs is not well understood. To examine this regulatory process, we investigated the effects of pancreaticobiliary juice diversion and reperfusion on exocrine pancreas using isolated rat pancreatic acini. Two groups of rats were surgically prepared for pancreaticobiliary juice diversion and reperfusion. Both groups received a liquid diet via a duodenal cannula and saline by intravenous infusion for 24 hours following surgery. Forty-eight hours after the surgery and infusions, the rats were sacrificed, and acinar cells were quickly isolated from each pancreas. Amylase release from isolated acini was measured in response to doses of cholecystokinin octapeptide (CCK-8) and carbachol. Acinar cell receptor binding was measured by using CCK-8 labeled with iodine 125 and N-tritium-methscopolamine bromide as radioligands. Amylase release in response to both CCK-8 and carbachol was significantly decreased in the diversion group when compared with that of the reperfusion group. Receptor binding sites of CCK-8 and methscopolamine bromide were similar in the diversion and reperfusion groups. The results suggest that cholecystokinin- and carbachol-mediated amylase response is affected by pancreaticobiliary juice diversion through a process that most likely involves alteration of post-receptor-mediated intracellular signaling pathways.

Mononuclear cells and cytokines in the cerebrospinal fluid of echovirus 30 meningitis patients

The local immune response to echovirus 30 meningitis in children was investigated in 2 ways: using flow cytometry to examine the mononuclear cell and lymphocyte subsets and enzyme-linked immunosorbent assays to examine the cerebrospinal fluid (CSF) levels of cytokines, including monocyte chemoattractant protein-1 (MCP-1), interferon gamma (IFN-gamma) and interleukin-12 (IL-12). The numbers of macrophages in the CSF were increased, in particular during the early part of the acute stage. The levels of MCP-1, which is responsible for the accumulation of macrophages, as well as those of IFN-gamma and IL-12, which play important roles in the activation of macrophages and T helper (Th) 1 cells, respectively, were increased in the CSF of patients compared with the levels found in the controls. Likewise, numbers of activated CD4 + and CD8 + T lymphocytes were increased in the CSF. Since the ratio of CD4/CD8 correlated with the age of the patients, CD8 + T lymphocytes in the CSF might play a more important role in younger children.

Involvement of serum mannan binding proteins and mannose receptors in uptake of mannosylated liposomes by macrophages

The roles of serum mannan binding protein (MBP) and the mannose receptor in the cellular uptake of mannosylated liposomes (Man-liposomes) by macrophages were studied. Man-liposomes were prepared by incorporating cholesten-5-yloxy-N-(4-((1-imino-2-beta-D-thiomannosylethyl)amino)butyl)formamide (Man-C4-Chol) into small unilamellar long circulating liposomes consisting of cholesterol (Chol) and distearoyl phosphatidylcholine (DSPC). In the in vitro cellular uptake study with cultured mouse peritoneal macrophages, [(3)H]Man-liposomes were taken up to a great extent, whereas no significant uptake was observed for [(3)H]cholesterol and DSPC liposomes without Man-C4-Chol (Bare-liposomes). The uptake of [(3)H]Man-liposomes was dose- and temperature-dependent and inhibited by an excess of mannosylated bovine serum albumin, suggesting their specific uptake via membrane mannose receptor-mediated endocytosis. Furthermore, it was demonstrated that (111)In-MBP binds strongly to Man-liposomes based on the recognition of Man-C4-Chol and markedly enhanced their uptake by macrophages. These results are supported by confocal laser microscopic images. In addition, in vivo hepatic uptake of (111)In-MBP was enhanced by Man-liposomes. On the other hand, the uptake of Man-liposomes was significantly reduced by preincubation with serum and further with MBP-depleted serum suggesting inhibitory effects of serum proteins such as albumin on mannose receptor-mediated endocytosis. The involvement of serum-type MBP and membrane mannose receptors in the uptake of Man-liposomes is thus suggested.

[Pulmonary edema in a child following laryngospasm triggered by a laryngeal mask airway during emergence from anesthesia]

A 9-year-old boy underwent biopsy of the tumor at the external auditory meatus under general anesthesia with a laryngeal mask airway(LMA). During emergence from anesthesia, laryngospasm with marked inspiratory effort and cyanosis occurred. The LMA was removed and the patient was orotracheally intubated following vecuronium administration. In spite of controlled ventilation with 100% oxygen, oxygen saturation remained at low 90s and pink frothy sputum appeared in the tracheal tube. We suspected negative pressure pulmonary edema and treated him with mechanical ventilation with positive end-expiratory pressure. Seventeen hours later the pink frothy sputum decreased and he was extubated. Laryngospasm during emergence from anesthesia with an LMA can induce negative pressure pulmonary edema, especially in pediatric patients.

Hemispheric lateralization in the cortical motor preparation for human vocalization

To investigate the cortical information processing during the preparation of vocalization, we performed transcranial magnetic stimulation (TMS) over the cortex while the subjects prepared to produce voice in response to a visual cue. The control reaction time (RT) of vocalization without TMS was 250-350 msec. TMS prolonged RT when it was delivered up to 150-200 msec before the expected onset of voice (EOV). The largest delay of RT was induced bilaterally over points 6 cm to the left and right of the vertex (the left and right motor areas), resulting in 10-20% prolongation of RT. During the early phase of prevocalization period (50-100 msec before EOV), the delay induced over the left motor area was slightly larger than that induced over the right motor area, whereas, during the late phase (0-50 msec before EOV), it was significantly larger over the right motor area. Bilateral and simultaneous TMS of the left and right motor areas induced delays not significantly different from that induced by unilateral TMS during the early phase, but induced a large delay well in excess of the latter during the late phase. Thus, during the cortical preparation for human vocalization, alternation of hemispheric lateralization takes place between the bilateral motor cortices near the facial motor representations, with mild left hemispheric predominance at the early phase switching over to robust right hemispheric predominance during the late phase. Our results also suggested involvement of the motor representation of respiratory muscles and also of supplementary motor cortex.

Clinical significance of low protein phosphatase-1 activity of blasts in acute myelogenous leukemia with high white cell counts

We have previously shown that protein phosphatase-1 (PP1) is the most abundant Ser/Thr phosphatase in human adult primary leukemic cells. To determine the clinical importance of PP1 expression, we compared PP1 activity of leukemic blasts with other putative prognostic factors in 46 patients with acute myelogenous leukemia (AML) who were treated with remission induction chemotherapy. PP1 was ubiquitously but differently expressed in various FAB subtypes (M1-M5), although PP1 activity was significantly higher in blasts of AML-M4 than in AML-M2. PP1 activity was significantly lower in elderly patients > or =55 years (P=0.005), and in those with high white cell counts > or =100,000/microl (P=0.039) at initial diagnosis. Correlation was observed between PP1 activity (<0.15 vs > or =0.15 nmol/min/10(8) cells) and prognosis of AML patients. Eleven of 46 patients with less than 0.15 nmol/min/10(8) cells (low PP1 activity group) had significantly lower overall survival than those with > or =0.15 nmol/min/10(8) cells (high PP1 activity group). The median overall survival was 8 months for patients with low PP1 activity compared to 27 months for those with high PP1 activity in their AML cells. Multivariate analysis using Cox's proportional hazard model showed that low PP1 activity significantly contributed to prognosis. This preliminary study suggests that low PP1 activity may be associated with shortened survival time for AML patients with high white cell counts.

Targeting Superoxide Dismutase to Renal Proximal Tubule Cells Inhibits Mitochondrial Injury and Renal Dysfunction Induced by Cisplatin

We recently reported the synthesis of a cationic superoxide dismutase (SOD) derivative (AH-SOD) that rapidly and selectively accumulates in and around proximal tubule cells and effectively dismutes superoxide radicals in situ. The present study revealed that administration of cis-diamminedichloroplatinum(II)-elicited oxidative stress in renal mitochondria, decreased the renal expression of Bcl-x, released cytochrome c from mitochondria to cytosol, and induced apoptosis and renal dysfunction by a mechanism that was inhibited by AH-SOD. These results suggest that targeting SOD to proximal tubule cells protects renal function and permits the administration of fairly high doses of nephrotoxic anticancer agents, such as cisplatin, without causing renal injury.

Somatic mutation of mitochondrial DNA in cancerous and noncancerous liver tissue in individuals with hepatocellular carcinoma

Unlike other types of cancer, hepatocellular carcinoma (HCC) is usually preceded by chronic inflammation caused by viral infection. The mutation of mitochondrial DNA (mtDNA) in hepatocarcinogenesis associated with viral infection was investigated. Compared with control liver tissue, the frequency of mtDNA mutations was markedly increased in both noncancerous and cancerous liver specimens from individuals with HCC. The accumulation of mtDNA mutations in HCC tissue reflected the degree of malignancy. The frequency of mtDNA mutations in HCC tissue was also greater than that described previously for other types of tumors. These observations suggest that the repeated destruction and regeneration of liver tissue associated with chronic viral hepatitis lead to the accumulation of mtDNA mutations. The genetic instability that results in the high rate of mtDNA mutation in cancerous liver tissue is also consistent with the multicentric hepatocarcinogenesis detected clinically.

Steno-occlusive changes in the external carotid system in moyamoya disease

To evaluate the steno-occlusive changes in the external carotid system in moyamoya disease, cerebral angiograms of 39 moyamoya patients were retrospectively reviewed. There were 26 females and 13 males, age ranged from 4 to 62 years with a mean of 26 years. Initial symptoms were ischaemia in 27 patients, haemorrhage in 9, and none in 3. Stenosis, occlusion, and dilatation in the external carotid system were analysed angiographically. No stenosis or occlusion of the superficial temporal artery, middle meningeal artery, or occipital artery was observed in either preoperative or postoperative follow-up angiograms in any patients. Steno-occlusive changes do not occur in the external carotid system, but are confined in the internal carotid system in moyamoya disease.

Column-switching high-performance liquid chromatography-electrospray ionization mass spectrometry for identification of heroin metabolites in human urine

In order to prove heroin (DAM) use, a simple, rapid and sensitive analytical method has been established by combining semi-microcolumn HPLC, a column switching technique and electrospray ionization mass spectrometry (ESI-MS). Urine samples were directly introduced to the system, and endogenous urinary constituents were removed by using on-line column switching solid-phase extraction with a strong cation-exchange (SCX) cartridge column (2.0 mm I.D. x 10 mm). Heroin and its metabolites enriched on the top of the column were then successfully analyzed with excellent separation by use of a SCX semi-microcolumn (1.5 mm I.D. x 150 mm), accompanied by ESI mass spectral detection. The proposed conditions are as follows: mobile phase, 10 mM ammonium acetate (pH 6.0)-acetonitrile (30:70, v/v) (for main separation) and 30 mM ammonium acetate (for trapping); flow-rates, 120 microl/min (for main separation) and 200 microl/min (for trapping); capillary voltage, +4.5 kV; cone voltage, 50 V. Linear calibration curves were obtained in the selected ion monitoring (SIM) mode using protonated molecular ions (m/z 370 for DAM, m/z 328 for MAM and m/z 286 for MOR) over the concentration ranges from 10 to 1000 ng/ml for morphine (MOR) and 1-100 ng/ml for DAM and 6-acetylmorphine (MAM). The detection limits were 0.1-3 ng/ml. Upon applying the scan mode, 2-30 ng/ml were the detection limits. The present HPLC-ESI-MS method was successfully applied to the determination of opiates in users' urine samples.

[Clinical study on prognostic factors in thyroid carcinoma]

We treated 227 patients, 45 men and 182 women, with thyroid carcinoma at our hospital from 1984 to 1998. Of these, 177 had papillary carcinoma and 50 follicular carcinoma. The extent of resection was based on tumor size in papillary carcinoma but not follicular carcinoma, and 70% of carcinoma patients underwent hemithyroidectomy. Neck lymph nodes were resected in 93.2% of papillary carcinoma patients, with D1 neck dissection in 45.7% and D2 or D3 neck dissection in 47.5%. In contrast, 70% of follicular carcinoma patients with lymph node resection had D1 dissection. Locoregional recurrence was noted in 22 patients and distant metastasis in 6 cases. Nonsurvivors numbered 17, 12 papillary and 5 follicular carcinoma patients, died of their primary disease. Almost all deaths were in patients with advanced disease, pT3 in 3, pT4 in 10, N1a in 3 and N1b in 8. The prognostic factors for papillary carcinoma were extracapsular spread, age, and distant metastasis, while the only factor for follicular carcinoma was distant metastasis. The 5-year survival for patients with papillary carcinoma was 93.0% and 10-year survival 88.8%, compared to 5-year survival for 93.5% of follicular carcinoma patients and 10-year survival for 93.5%.

Observation of untreated patients with neuroblastoma detected by mass screening: a "wait and see" pilot study

BACKGROUND

Recent studies have indicated that mass screening for neuroblastoma detects tumors that otherwise would have regressed spontaneously without recognition. Therefore, we started an observation program for these patients to determine how frequently spontaneous regression occurs.

PROCEDURE

Eighteen patients were detected by mass screening between June 1994 and December 1996. Eight of these cases matched the following criteria and entered the observation program: Stage I or II, less than 5 cm in diameter; no involvement of large vessels or organs; not difficult to resect; informed consent. If there were an increase in tumor size, an elevation of tumor markers, or evidence of metastasis, the tumor would be immediately resected.

RESULTS

Five of the eight cases showed spontaneous regression. Although the remaining three tumors were resected 6-10 months after diagnosis, all patients survived without evidence of recurrence.

CONCLUSIONS

At least 60% of neuroblastoma cases who entered our observation program regressed spontaneously.

Moyamoya disease and coronary artery disease--case report

A 26-year-old female with idiopathic moyamoya disease developed chest pain with concomitant ST depression on electrocardiography. Coronary angiography detected no stenotic lesions in the epicardial coronary arteries. The clinical diagnosis was vasospastic angina pectoris. She was medicated with calcium antagonists, which reduced the frequency of chest pain episodes. Angina pectoris is a rare occurrence in young patients with moyamoya disease. Coronary artery disease and moyamoya disease may have common etiological factors.

Clarithromycin inhibits NF-kappaB activation in human peripheral blood mononuclear cells and pulmonary epithelial cells

Macrolide antibiotics modulate the production of proinflammatory cytokines in vivo and in vitro. Transcription of the genes for these proinflammatory cytokines is regulated by nuclear factor kappaB (NF-kappaB). We examined whether or not clarithromycin inhibits the activation of NF-kappaB induced by tumor necrosis factor alpha (TNF-alpha) or staphylococcal enterotoxin A (SEA) in human monocytic U-937 cells, a T-cell line (Jurkat), a pulmonary epithelial cell line (A549), and peripheral blood mononuclear cells (PBMC). Flow cytometry revealed that clarithromycin suppresses NF-kappaB activation induced by TNF-alpha in U-937 and Jurkat cells in a concentration-related manner. Western blot analysis also demonstrated that clarithromycin inhibits NF-kappaB activation induced by TNF-alpha in U-937, Jurkat, and A549 cells and PBMC and by SEA in PBMC. Western blot analysis of cytoplasmic extracts of A549 cells revealed that this inhibition is not linked to preservation of expression of the IkappaBalpha protein. The chloramphenicol acetyltransferase assay indicated that NF-kappaB-dependent reporter gene expression is suppressed in U-937 cells pretreated with clarithromycin. These findings are consistent with the idea that clarithromycin suppresses the production of proinflammatory cytokines via inhibition of NF-kappaB activation.

Molecular cloning of delta-4, a new mouse and human Notch ligand

Complementary DNAs encoding a previously unidentified mouse Notch ligand and its human ortholog were isolated. The new Notch ligand contains a signal sequence, a DSL domain, eight epidermal growth factor-like repeats, a transmembrane domain, and an intracellular region, all of which are characteristics of members of the Delta protein family. The new protein was therefore designated Delta-4. Several previously unidentified sequences in both the extracellular and intracellular regions were shown to be conserved among vertebrate Delta proteins. The tissue distribution of Delta-4 mRNA resembles that previously described for Notch-4 (Int-3) transcripts. However, in situ hybridization with mouse lung revealed that Delta-4 mRNA is abundant in squamous alveolar cells that neighbor endothelial cells; Notch-4 expression is largely restricted to the latter cell type. Soluble forms of the extracellular portion of Delta-4 inhibit the apparent proliferation of human aortic endothelial cells, but not human pulmonary arterial endothelial cells.

High incidence of arterial dissection associated with left vertebral artery of aortic origin

The incidences of arterial dissection of the vertebral artery (VA) of aortic origin and VA of subclavian artery origin were determined. The origins of the left and right VAs were confirmed by angiography in 860 and 717 patients, respectively. Left VA of aortic origin was found in 21 patients (6 females and 15 males) but no right VA of aortic origin was found. Left VA of left subclavian artery origin was found in 837 patients and right VA of right subclavian artery origin in 717 patients. Arterial dissection of the VA occurred in 17 patients (6 females and 11 males), four patients with left VA of aortic origin, seven with left VA of left subclavian artery origin, four with right VA of right subclavian artery origin, and two with bilateral VAs of subclavian artery origin. Left VA of aortic origin (4 of 21 patients) was associated with a significantly higher incidence of VA dissection than left VA of left subclavian artery origin and right VA of right subclavian artery origin (p < 0.001). Left VA of aortic origin is associated with a predilection for VA dissection in comparison to VA of subclavian artery origin.

Nitric oxide regulates mitochondrial respiration and functions of articular chondrocytes

OBJECTIVE

Biologic effects of nitric oxide (NO) have been shown to increase under hypoxic conditions. Because the oxygen tension in joint cavities of patients with arthritis is fairly low, biologic effects of NO would be expected to be significantly large in these compartments. This study was undertaken to investigate the effects of NO on the energy metabolism and functions of articular chondrocytes under different oxygen tension conditions.

METHODS

Articular chondrocytes from rabbits were cultured under various oxygen concentrations in the presence or absence of NO and NOC18, an NO donor. Cellular respiration was measured using a Clark-type oxygen electrode. Levels of ATP in the cells were determined according to the luciferin-luciferase method. Cellular synthesis of proteoglycans was determined by measuring the incorporation of radioactivity (derived from 35S-labeled SO4) into glycosaminoglycans. Expression of stress-related proteins was evaluated by Western blotting analysis using specific antibodies.

RESULTS

Respiration and ATP synthesis of cultured chondrocytes were inhibited by NO, particularly under low oxygen concentrations. The presence of either NO or specific inhibitors of mitochondrial electron transport suppressed the synthesis of proteoglycans without affecting cell viability. When exposed to NO, cellular levels of heat-shock protein 70 (hsp70) and heme oxygenase 1 (HO-1) increased markedly. The presence of inhibitors of mitochondrial electron transport also increased cellular levels of hsp70 and HO-1.

CONCLUSION

These results suggest that NO generated in the joint might inhibit energy metabolism and the synthesis of proteoglycans of chondrocytes, thereby modulating pathophysiologic processes occurring in patients with arthritis.

Protective effects of dietary docosahexaenoic acid against kainate-induced retinal degeneration in rats

PURPOSE

To investigate the role played by docosahexaenoic acid (DHA) in the retina, and more specifically, its ability to protect the retina from kainic acid (KA)-induced retinal damage.

METHODS

Three-week-old female Wistar rats were used. DHA (1000 mg/kg per day) was fed to the rats for 7, 14, and 28 days, and the concentrations of DHA and arachidonic acid (AA) in the retina and serum were measured. In another group of rats, the right eyes were injected intravitreally with 3.12 nanomoles KA after DHA supplementation for 14 days. Electroretinograms (ERGs) elicited by different stimulus intensities were recorded before and on days 1, 7, and 14 after the KA injection. The amplitudes and implicit times of the a- and b-waves were compared. The number of cells in the ganglion cell layer (GCL) and inner nuclear layer (INL) were compared by histopathologic examination.

RESULTS

The concentration of DHA in the serum and retina increased after DHA supplementation. The concentration of AA in serum decreased with DHA supplementation, but the concentration of AA in retina did not show any significant change. The b-waves of the ERGs recorded after KA injection were significantly attenuated in both groups of rats. However, the attenuation was significantly less in the DHA-supplemented rats than in gum arabic-supplemented control rats. The numbers of cells in the INL and GCL were significantly higher in DHA-supplemented rats.

CONCLUSIONS

These results indicate that DHA supplementation can partially counteract KA neurotoxicity in the rat retina. DHA may play a role in modulating neuronal excitability by reducing KA-induced responses in the retina.

Increased plasma thrombomodulin as a vascular endothelial cell marker in patients with thrombotic thrombocytopenic purpura and hemolytic uremic syndrome

Several hemostatic and vascular endothelial cell markers were measured in 39 patients with thrombotic thrombocytopenic purpura (TTP)/hemolytic uremic syndrome (HUS) and in 20 healthy volunteers to examine the relationship between the occurrence of hemostatic abnormality or vascular endothelial cell injury and patient outcome. The plasma levels of von Willebrand factor, tissue plasminogen activator (TPA), plasminogen activator inhibitor (PAI-1), and the TPA-PAI-1 complex were significantly increased in TTP/HUS patients; however, the levels of these markers were not significantly different between TTP/HUS patients who survived and those who died, suggesting that these markers might not be directly related to outcome. The plasma levels of soluble granule membrane protein (GMP)-140 were significantly higher in TTP/HUS patients than in healthy volunteers, suggesting that platelets and vascular endothelial cells are activated or injured in TTP/HUS. There was no significant difference in GMP-140 levels between TTP/HUS patients with good and poor prognoses; this may be owing to the release of GMP-140 from platelets. The plasma thrombomodulin (TM) levels in TTP/HUS patients were significantly higher than in healthy volunteers; the plasma TM levels were significantly higher in patients who died than in patients who survived. These findings showed that TM levels reflect the outcome and that the outcome of TTP/HUS depends on the presence vascular endothelial cell injury. The plasma protein C and antithrombin levels were markedly reduced in TTP/HUS patients who died compared with those who survived. These findings suggest that reduced plasma antithrombin and protein C may be useful markers of systemic vascular endothelial injury. In conclusion, the results of this study showed that the outcome of TTP/HUS is related to vascular endothelial cell injury and that plasma TM, antithrombin, and protein C levels may be useful markers of systemic vascular endothelial cell injury.

Leptomeningeal contrast enhancement in moyamoya: its potential role in postoperative assessment of circulation through the bypass

Leptomeningeal contrast enhancement (LMCE) is one of the MRI features of moyamoya. Its clinical significance, however, is not elucidated. Our purpose was to characterise LMCE on MRI and to evaluate its role in the assessment of circulation through a surgically established bypass in moyamoya. We studied 16 patients with idiopathic moyamoya (seven males, nine females, includingt four children, aged 7 to 54 years, mean 24 years) who underwent T1-weighted MRI before and after intravenous contrast medium. The presence of LMCE, its intensity and anatomical distribution, catheter angiographic findings, and relation of LMCE to the bypass surgery were assessed. More LMCE was seen in the cerebrum in most patients with moyamoya than in normal controls. LMCE in the brain stem and cerebellum was minimal, similar to that seen in the controls. LMCE was less prominent following surgery than before operation or in patients who did not undergo surgery. In three patients examined both before and after operation LMCE became less prominent following bypass surgery. As LMCE becomes less prominent after "effective" bypass surgery, this may be used for evaluation of effectiveness of surgery in moyamoya.

Cross-talk between NO and oxyradicals, a supersystem that regulates energy metabolism and survival of animals

Mammalian tissues have large amounts of available ATP which are generated by oxidative phosphorylation in mitochondria. For the maintenance of the human body, a large amount of oxygen is required to regenerate these ATP molecules. A small fraction of the inspired oxygen is converted to superoxide radical and related metabolites even under physiological conditions. Most reactive oxygen species react rapidly with a variety of molecules thereby interfering with cellular functions and induce various diseases. Nitric oxide (NO) is an unstable gaseous radical with high affinity for various molecules, such as hemeproteins, thiols, and related radicals. NO easily penetrates through cell membrane/lipid bilayers, forms dissociable complexes with these molecules and modulates cellular metabolism and functions. Because NO has an extremely high affinity for the superoxide radical, the occurrence of the latter might decrease the biological function of NO. Thus, superoxide radicals in and around vascular endothelial cells play critical roles in the pathogenesis of hypertension and vasogenic tissue injury. Because NO also reacts with molecular oxygen, it rapidly loses its biological activity, particularly under ambient atmospheric conditions where the oxygen tension is unphysiologically high. Thus, biological functions of NO are determined by the local concentrations of molecular oxygen and superoxide radicals.

[Perioperative evaluation of cerebral hemodynamics by transcranial Doppler ultrasonography in patient with hemolytic uremic syndrome]

Major central nervous system (CNS) complications such as seizures and coma, occur in about 30% of children with hemolytic uremic syndrome (HUS). Serious CNS involvement is associated with an increased mortality. The purpose of this study was to evaluate intracranial hemodynamics in HUS encephalopathy. We measured mean blood flow velocity and pulsatility index (PI) of the middle cerebral artery (MCA) with transcranial Doppler (TCD) in a two year-old girl with acute encephalopathy, and compared them to those in a one year-old girl with febrile convulsion incidentally complicating HUS (a disease control). In the patient with HUS encephalopathy TCD demonstrated abnormally low PI of 0.58, while the magnetic resonance imaging (MRI) and single-photon emission-computed tomography (SPECT) reveal no abnormal findings in the acute stage. The abnormal TCD findings disappeared with her recovery. In the HUS patient with febrile convulsion alone, TCD demonstrated normal maximal flow velocity and PI. Thus TCD may be useful in evaluating intracranial hemodynamics in HUS encephalopathy in the absence of MRI and SPECT abnormalities at the early stage of illness.

Increased plasma levels of tissue factor pathway inhibitor-activated factor X complex in patients with disseminated intravascular coagulation

Plasma levels of tissue factor pathway inhibitor (TFPI)-activated factor Xa (FXa) complex were measured in patients with disseminated intravascular coagulation (DIC), pre-DIC, and DIC. Plasma levels of plasmin-plasmin inhibitor complex (PPIC), D-dimer, and soluble fibrin monomer (SFM) were significantly higher in patients with DIC than in those with pre-DIC or non-DIC; the levels of these hemostatic markers were significantly higher in patients with pre-DIC than in those with non-DIC. Plasma levels of thrombin-antithrombin complex (TAT) were significantly higher in patients with DIC or pre-DIC than in those with non-DIC. Plasma levels of tissue factor (TF), total TFPI, free TFPI, and TFPI-Xa complex were significantly higher in patients with DIC than in those with non-DIC. Plasma levels of TFPI-Xa complex were significantly increased in patients with pre-DIC as compared to those with non-DIC; however, plasma free TFPI levels were significantly decreased in patients with pre-DIC as compared to those with non-DIC. These findings suggest that free TFPI might be consumed in the pre-DIC state, thereby confirming the activation of the extrinsic pathway. Plasma levels of TFPI-Xa complex were significantly correlated with TF, free TFPI, and total TFPI. Increased plasma TFPI-Xa complex levels might be useful for the diagnosis of DIC or pre-DIC, particularly that occurring by activation of the extrinsic pathway of blood coagulation.

Increased peripheral blood interferon gamma-producing T cells in acute disseminated encephalomyelitis

There have been few reports on immunological studies in patients with acute disseminated encephalomyelitis (ADEM). We investigated the immunological features of ADEM using flow cytometry to examine interferon gamma (IFN-gamma)-and interleukin 4 (IL-4)-producing peripheral blood CD3+T cells from four patients with ADEM, three other neurological disorders (Fisher syndrome, epilepsy and aseptic meningitis) and 10 healthy children. IFN-gamma-producing CD3+T cells were increased in ADEM during the acute stage. In a relapsing case of ADEM, the percentages of IFN-gamma-producing CD3+T cells correlated with disease activity. There were no significant changes of IL-4-producing CD3+T cells in ADEM during the acute and convalescent stages. In conclusion, peripheral blood IFN-gamma-producing T cells are related to the pathogenesis at the early phase of the acute ADEM.

[The limitations of three-dimensional CT angiography (3D-CTA) in the diagnosis of cerebral aneurysms]

OBJECT

The purpose of this study is to show some limitations of 3D-CTA to diagnose cerebral aneurysms.

METHODS

Sixteen saccular aneurysms less than 10 mm in diameter were included. Large and complicated aneurysms were excluded.

RESULTS

Although information about perforating arteries from the posterior cerebral artery is very important for surgery of basilar bifurcation aneurysms, 3D-CTA could not delineate the perforating arteries. A small posterior communicating artery (Pcom.A.) was not detected, and it was very difficult to differentiate infundibular dilatation of the Pcom. A. from an aneurysm. A small aneurysm of the distal middle cerebral artery could not be detected. Flow direction can not be determined by 3D-CTA, and nor could the side of the neck of the anterior communicating artery aneurysm be determined. Fenestration of the anterior communicating artery and the origin of the triple anterior cerebral artery were both misdiagnosed as anterior communicating artery aneurysms.

CONCLUSION

It is premature to consider 3D-CTA as a replacement for conventional angiography.

[Dural arteriovenous fistulae in the anterior cranial fossa--report of three cases]

Dural arteriovenous fistulae (DAVF's) in the anterior cranial fossa are uncommon. We encountered three patients with DAVF's in the anterior cranial fossa and reviewed the pertinent literature with regard to the etiology. All patients are middle-aged males. Two of three patients had massive intracranial hemorrhage, subarachnoidal hemorrhage in one and subdural hemorrhage in the other. One patient had a ruptured middle cerebral artery aneurysm and DAVF at the anterior cranial fossa was detected only incidentally. Angiographically, blood supplies were from the bilateral enlarged anterior ethmoidal arteries. These drained into the superior sagittal sinus via dilated frontal cortical veins. In all the patients, coagulation of the fistulous connections was carried out and the postoperative courses were uneventful. Angiographies revealed complete disappearance of the DAVF's. In conclusion, compared to cases of DAVF's in the other locations, DAVF's of the anterior cranial fossa are more likely to be brought on by sudden massive intracranial hemorrhage, and should be treated, even if asymptomatic, at the time of diagnosis. Surgical obliteration of the fistulous connection is sufficient treatment for DAVF in the anterior cranial fossa. Literature review strongly suggests that DAVF's involving the anterior cranial fossa are acquired lesions.

Abnormalities of brain perfusion in echovirus type 30 meningitis

From May to August 1998 an epidemic of aseptic meningitis (AM) due to echovirus type 30 (E30) occurred in Yamaguchi prefecture, Japan. We performed single-photon emission-computed tomography (SPECT) to evaluate cerebral perfusion during the acute stage in 27 patients with AM due to E30. Moreover, we measured the cerebrospinal fluid (CSF) concentrations of soluble tumor necrosis factor receptor (sTNF-R) and interleukin-1 beta (IL-1beta) in all 27 patients, and the serum concentration of soluble E-selectin (sE-selectin) in 19 of the 27 patients, which is responsible for vasculitis, by means of a sandwich enzyme-linked immunosorbent assay. In 20 of the 27 (74.1%) children, SPECT imaging revealed localized cerebral hypoperfusion without abnormal focal neurological findings or symptoms. Follow-up SPECT after about 1 month revealed no abnormalities. The CSF concentrations of sTNF-R and IL-1beta, and the serum concentration of sE-selectin in the group with abnormal findings on SPECT were significantly higher than those in the group without abnormal findings on SPECT and the control subjects. Our results indicate that transient reduced regional blood flow is a frequent finding in children with AM due to E30 infection and that this abnormal finding may be induced by cerebral vasculitis.

Diagnosis of disseminated intravascular coagulation by hemostatic molecular markers

In the present study, the positive rate of thrombin-antithrombin complex (TAT), plasmin-plasmin inhibitor complex (PPIC), soluble fibrin monomer (sFM), and D-dimer for the diagnosis of disseminated intravascular coagulation (DIC) was evaluated. The study comprised 307 patients with DIC, 123 with pre-DIC, and 121 with non-DIC. Plasma levels of TAT, PPIC, sFM, and D-dimer were significantly higher in DIC and pre-DIC patients than in non-DIC patients. In DIC patients, the positive rate of sFM was high and that of D-dimer was low; the positive rate of PPIC was higher in patients with hematopoietic malignancy than in those without this disease. In pre-DIC patients, the positive rate of all markers was low (<0.16), and the positive rate of PPIC was relatively high. In non-DIC patients, the positive rate of all hemostatic markers was low (<0.16), that of sFM being the lowest. Scoring the positive rate of TAT, PPIC, and sFM disclosed the following results: 72% of DIC patients had three or more points, 17.6% of pre-DIC patients had three or more points, and almost all (96.6%) non-DIC patients had two or less points. Scoring the positive rate of TAT, PPIC, and D-dimer disclosed the following results: 52.9% of DIC patients and 27.4% of pre-DIC patients had three or more points and almost all (96.7%) non-DIC patients had 2 or less points. These data suggest that the combination of TAT, PPIC, and sFM is useful for making the diagnosis of DIC.

[Neonatal hydrocephalus-volume determinations using computed tomography]

Computed tomography potentially offers the most accurate noninvasive means of estimating in vivo volumes. Contiguous 5 and 10-mm-thick CT scans were obtained through phantom and neonatal cranium. Cross-sectional areas were calculated for each individual scan and volumes then determined with summation-of-areas technique. The indirect intracranial volume measurement technique was then used to compare hydrocephalic and non-hydrocephalic intracranial and ventricular volumes in nine neonates. Our findings show that intracranial volumes of hydrocephalic neonates with head circumference of more than 39 cm, have 1.97 times larger than control group. The ratios of lateral ventricle versus intracranial volume are 0.57 +/- 0.2 in hydrocephalic babies and 0.0062 +/- 0.001 in control babies, respectively(p < 0.005).

Significance of chemokines and activated platelets in patients with diabetes

Levels of platelet-derived microparticles (PMPs), platelet activation markers (P-selectin expressed on, or annexin V binding to, platelets (plt:P-selectin or plt:annexin V, respectively)), chemokines (IL-8, monocyte chemotactic peptide-1 (MCP-1), and regulated on activation normally T-cell expressed and secreted (RANTES)), and soluble P- and E-selectins were compared in peripheral blood from diabetic and control patients in order to develop a better understanding of their potential contribution to diabetic vascular complications. Significant increases were found for PMPs, plt:P-selectin, MCP-1, RANTES and soluble P- and E-selectins in diabetic individuals, whereas IL-8 levels were similar. Furthermore, after ticlopidine treatment, most of these factors receded to baseline levels observed in non-diabetic patients. Our findings indicate that ticlopidine might be able to prevent or reduce vascular complications in diabetic patients.

Observations on metal concentrations in three species of shark (Deania calcea, Centroscymnus crepidater, and Centroscymnus owstoni) from southeastern Australian waters

Deep sea dog sharks (Deania calcea, Centroscymnus crepidater, and Centroscymnus owstonii) were captured from the waters off western Victoria, Australia, in April and May 1998. The elements As, Ca, Cd, Cu, Fe, Hg, K, Mg, Mn, Na, Sr, and Zn were detected in the muscle tissue. The concentrations of Al, Ba, Be, Cr, Mo, Ni, Pb, and V were below the detection limits of the instrumental techniques employed (ICP-ES and GF-AAS). However, significant concentration differences between species were detected for As, Cd, Hg, and Zn. C. owstoni contained the highest concentrations of each of these elements. The concentrations of Cu, Pb, and Zn in each species were below the maximum levels permitted in food by the Australian Food Standards Code. The maximum permitted concentrations of As and Hg were exceeded in all species, and weekly consumption of 400 g of any of these sharks would result in intake of more than the FAO's provisional tolerable weekly intake. Although C. crepidator and D. calcea have strong relationships between length and mercury concentration, C. owstoni does not. Placing C. crepidator and C. owstoni in the same genus, therefore, is worth re-examination as the mechanisms for controlling mercury in C. owstoni appear to differ from that used by both C. crepidator and D. calcea.

Abnormal regional cerebral blood flow in childhood autism

Neuroimaging studies of autism have shown abnormalities in the limbic system and cerebellar circuits and additional sites. These findings are not, however, specific or consistent enough to build up a coherent theory of the origin and nature of the brain abnormality in autistic patients. Twenty-three children with infantile autism and 26 non-autistic controls matched for IQ and age were examined using brain-perfusion single photon emission computed tomography with technetium-99m ethyl cysteinate dimer. In autistic subjects, we assessed the relationship between regional cerebral blood flow (rCBF) and symptom profiles. Images were anatomically normalized, and voxel-by-voxel analyses were performed. Decreases in rCBF in autistic patients compared with the control group were identified in the bilateral insula, superior temporal gyri and left prefrontal cortices. Analysis of the correlations between syndrome scores and rCBF revealed that each syndrome was associated with a specific pattern of perfusion in the limbic system and the medial prefrontal cortex. The results confirmed the associations of (i) impairments in communication and social interaction that are thought to be related to deficits in the theory of mind (ToM) with altered perfusion in the medial prefrontal cortex and anterior cingulate gyrus, and (ii) the obsessive desire for sameness with altered perfusion in the right medial temporal lobe. The perfusion abnormalities seem to be related to the cognitive dysfunction observed in autism, such as deficits in ToM, abnormal responses to sensory stimuli, and the obsessive desire for sameness. The perfusion patterns suggest possible locations of abnormalities of brain function underlying abnormal behaviour patterns in autistic individuals.

Significance of platelet-derived microparticles and activated platelets in diabetic nephropathy

We measured levels of platelet-derived microparticles (PMP), which have coagulative activity and are produced by platelet activation or physical stimulation, and CD62P/CD63-positive platelets in patients with diabetes mellitus to determine their clinical significance and effects on complications of diabetes including diabetic nephropathy. We also compared these levels before and after administration of the antiplatelet drug cilostazol. Plasma PMP and CD62P/CD63-positive platelet levels were significantly higher in patients with diabetes mellitus than normal controls. CD62P-positive platelet levels were significantly higher in patients with nephropathy than in patients without complications. After administration of cilostazol, PMP and CD62P/CD63-positive platelet levels were significantly decreased. The increases in platelet activity and its related procoagulant activity appear to account in part for the hypercoagulability observed in diabetes mellitus. Our findings suggest that activated platelets might play a role in the development of diabetic nephropathy. Furthermore, antiplatelet therapy with cilostazol for diabetic patients may be useful as antithrombin therapy including antiplatelet therapy, since it suppresses the production of intrinsic coagulants produced by platelet activation.

Elevated cerebrospinal fluid level of ciliary neurotrophic factor in acute disseminated encephalomyelitis

We investigated the concentrations of ciliary neurotrophic factor (CNTF) in cerebrospinal fluid (CSF) from children with inflammatory diseases of the central nervous system. We studied 6 children with acute disseminated encephalomyelitis (ADEM), 14 with acute encephalitis/encephalopathy, 17 with bacterial meningitis, and 24 with aseptic meningitis. We found that CNTF was undetectable in the CSF of all children with acute encephalitis/encephalopathy during the acute and convalescent stages, those with aseptic meningitis, and the 25 control subjects. In children with ADEM, CNTF was undetectable during the acute stage, but its concentration was elevated in all six at the convalescent stage. In children with bacterial meningitis, the CNTF concentration was slightly elevated in two of the 17 during the acute stage and another two at the convalescent stage. Our results suggest that CNTF is part of the regulatory system for oligodendrocyte functions, such as remyelination, in ADEM.

Superparamagnetic iron oxide-enhanced magnetic resonance images of hepatocellular carcinoma: correlation with histological grading

Superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance (MR) imaging has been used for the detection of hepatic tumors. However, little is known about this technique in relation to hepatocellular carcinoma (HCC). The aim of this study was to investigate whether SPIO-enhanced MR imaging can be useful in assessing histological grades of HCC. The authors studied histologically proven tumors including 31 HCCs and 6 dysplastic nodules. The ratio of the Kupffer-cell count in the tumorous tissue relative to that in the nontumorous tissue (Kupffer-cell-count ratio) decreased as HCCs became less well differentiated. The ratio of the intensity of the tumorous lesion to that of the nontumorous area on SPIO-enhanced MR images (SPIO intensity ratio) correlated inversely with Kupffer-cell-count ratio in HCCs and dysplastic nodules (r = -.826, P <.001) and increased as the degree of differentiation of HCCs decreased, indicating that the uptake of SPIO in HCCs decreased as the degree of differentiation of HCCs declined. All of the dysplastic nodules and some well-differentiated HCCs showed hypointense or isointense enhancement, relative to the surrounding liver parenchyma, indicating greater or similar uptake of SPIO in the tumor when compared with nontumorous areas. These results suggest that SPIO-enhanced MR imaging reflects Kupffer-cell numbers in HCCs and dysplastic nodules, and is useful for estimation of histological grading in HCCs, although uncertainties persist in differentiating dysplastic nodules from well-differentiated HCCs.

Primary structure and expression of peroxisomal acetylspermidine oxidase in the methylotrophic yeast Candida boidinii

Acetylspermidine oxidase (ASOD) belongs to a family of FAD-containing amine oxidases and catalyzes the oxidation of N-acetylated spermidine in polyamine metabolism. ASOD was purified to apparent homogeneity from cells of the methylotrophic yeast Candida boidinii grown on spermidine as the sole nitrogen source. C. boidinii ASOD catalyzed the oxidation of only N(1)-acetylspermidine. Based on partial amino acid sequences, oligonucleotide primers were designed for polymerase chain reaction, and the ASOD-encoding gene, ASO1, was cloned. The open reading frame encoding ASO1 was 1530 bp long and corresponded to a protein of 509 amino acid residues (calculated molecular mass=57167 Da). ASO1 contained a FAD-binding motif of G-A-G-I-A-G in the N-terminal region and carried an amino acid sequence of -S-K-L at the C-terminal, representing a typical peroxisome targeting signal 1. ASOD was localized in the peroxisomes in overexpressed C. boidinii. To our knowledge, this is the first report on the gene coding for ASOD that can catalyze the oxidation of N-acetylated polyamine as a substrate, from any type of organism.

Discrimination of dimethylamphetamine and methamphetamine use: simultaneous determination of dimethylamphetamine-N-oxide and other metabolites in urine by high-performance liquid chromatography-electrospray ionization mass spectrometry

A simple and sensitive method by high-performance liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS) has been investigated for the simultaneous determination of dimethylamphetamine (DMA), its specific yet labile main metabolite dimethylamphetamine-N-oxide (DMAO), and other metabolites, methamphetamine (MA) and amphetamine (AP), in urine. A combination of Bond Elut SCX columns for the solid-phase extraction of urine and a semi-micro SCX column for LC separations provided satisfactory results. The use of acetonitrile/5mM ammonium acetate buffer adjusted to pH 4 (65:35, v/v) as the mobile phase at a flow rate of 0.2 mL/min was found to be the most effective. The detection limits were 5 ng/mL for DMAO, 10 ng/mL for DMA and MA, and 50 ng/mL for AP in the SIM mode.

Effect of sarpogrelate hydrochloride on platelet-derived microparticles and various soluble adhesion molecules in diabetes mellitus

We measured platelet-derived microparticles, activated platelets, and various adhesion molecules in 48 patients with diabetes mellitus. We also performed a comparative study of these parameters before and after administration of sarpogrelate hydrochloride. The numbers of platelet-derived microparticles and activated platelets were increased significantly in diabetic patients, and CD63-positive platelets were increased in patients with diabetic complications and poorly controlled blood glucose. Soluble adhesion molecules and thrombomodulin were also increased significantly. After administration of sarpogrelate hydrochloride, not only CD62p- and CD63-positive platelets, but also platelet-derived microparticles were decreased significantly. Soluble adhesion molecules and thrombomodulin were also significantly decreased after the treatment. These data suggest that (a) in patients with diabetes, antiplatelet therapy with sarpogrelate hydrochloride is a useful antithrombin therapy because it suppresses the production of intrinsic coagulants by activated platelets; and (b) sarpogrelate hydrochloride decreases endothelial cell damage via adhesion molecules.

Chronological changes in nonhaemorrhagic brain infarcts with short T1 in the cerebellum and basal ganglia

Our purpose was to investigate nonhaemorrhagic infarcts with a short T1 in the cerebellum and basal ganglia. We carried out repeat MRI on 12 patients with infarcts in the cerebellum or basal ganglia with a short T1. Cerebellar cortical lesions showed high signal on T1-weighted spin-echo images beginning at 2 weeks, which became prominent from 3 weeks to 2 months, and persisted for as long as 14 months after the ictus. The basal ganglia lesions demonstrated slightly high signal from a week after the ictus, which became more intense thereafter. Signal intensity began to fade gradually after 2 months. High signal could be seen at the periphery until 5 months, and then disappeared, while low or isointense signal, seen in the central portion from day 20, persisted thereafter.

Decreased tissue factor and tissue-plasminogen activator antigen in relapsed acute promyelocytic leukemia

This study evaluated hemostatic data in 28 patients with newly diagnosed acute promyelocytic leukemia (APL) and 15 patients with relapsed APL. Activated partial thromboplastin time and prothrombin time were prolonged at initial onset of APL. Plasma level of fibrinogen was significantly decreased in patients with initial disease of APL, but it was not decreased significantly during the relapse of APL. Plasma fibrin and fibrinogen degradation products levels were significantly increased and platelet counts significantly decreased in both groups. Plasma levels of antiplasmin significantly decreased at initial onset but not during relapse. Plasma levels of antithrombin were within normal range in patients with initial disease but significantly decreased in those with relapse. Plasma levels of D-dimer, soluble fibrin monomer (sFM), plasmin-plasmin inhibitor complex (PPIC), and thrombin antithrombin complex (TAT) levels were significantly high in both groups. Plasma levels of PPIC, sFM, and D-dimer were significantly higher at initial onset of APL than during relapse. However, there was no significant difference in DIC score between patients with initial onset and those with relapse; plasma levels of tissue factor (TF) significantly increased in both groups, but they were significantly higher at initial onset of APL than during relapse. TF and tissue type plasminogen activator (t-PA) antigen levels in leukemic cell lysate were significantly increased in both groups, and they were significantly lower during relapse than at initial onset. Hemostatic abnormalities occurring in patients with relapsed APL might be the result of the decrease of TF and t-PA in leukemic cells. These findings suggest that DIC in APL patients with relapse might not be caused only by TF and t-PA and thus should be treated with different therapy from patients with initial onset of APL.

Cerebrospinal fluid concentrations of alpha-melanocyte-stimulating hormone in bacterial and aseptic meningitis

alpha-Melanocyte-stimulating hormone (alpha-MSH) has potent anti-inflammatory effects in several experimental models of inflammation. It inhibits both the actions and production of proinflammatory cytokines and neutrophil migration. We investigated whether alpha-MSH in cerebrospinal fluid (CSF) increases during the acute stage in patients with bacterial and aseptic meningitis by measuring alpha-MSH in CSF via radioimmunoassay. The alpha-MSH concentrations in CSF from the children with bacterial meningitis who survived (n = 8), those with aseptic meningitis (n = 16), and the control subjects (n = 23) were all below the detection limit. However, CSF alpha-MSH was elevated in four of the five children with bacterial meningitis who had neurological sequelae. We speculate that elevated alpha-MSH levels in CSF during acute bacterial meningitis reflect negative feedback in response to severe inflammation associated with neurological sequelae induced by proinflammatory cytokines.

CONCLUSION

CSF alpha-MSH is elevated in children with severe bacterial meningitis who had neurological sequelae.

Long-term responders without eradication of hepatitis C virus after interferon therapy: characterization of clinical profiles and incidence of hepatocellular carcinoma

AIMS/BACKGROUND

The aim of this study was to determine the characteristics of patients with chronic hepatitis C showing long-term normalization of alanine aminotransferase (ALT) without eradication of HCV RNA, as well as to investigate the incidence of hepatocellular carcinoma (HCC) in such patients.

METHODS

Four hundred and nineteen patients with histologically-proven chronic hepatitis C who had received interferon (IFN) therapy were studied. Complete response (CR) was defined as persistent normalization of ALT levels with eradication of serum HCV RNA (n= 126). Long-term biochemical response with positive HCV RNA (HCV-positive BR) was defined as a normal ALT level at 6 months after IFN therapy with further persistent normalization of ALT levels for 2 or more years without eradication of serum HCV RNA (n=49). All other patterns were classified as non-response (NR, n=244).

RESULTS

Mean follow-up periods of CR, HCV-positive BR and NR groups were 4.9, 5.2 and 4.9 years, respectively. The HCV-positive BR group had significantly higher serum HCV RNA levels and a higher rate of HCV serological group 1 classification than the CR group. The other characteristics of the HCV-positive BR group were lower histologic activity, lower ALT levels, and a higher rate of females when compared with both the CR and NR groups. Histologic staging in the HCV-positive BR group was significantly lower than that in the NR group. Cumulative incidences of HCC estimated by the Kaplan-Meier method in both the CR and HCV-positive BR groups were significantly lower than those in the NR group (log-rank test, CR vs NR p<0.001, HCV-positive BR vs NR p=0.026).

CONCLUSION

The patients with HCV-positive BR were virologically different from those with CR, and had lower ALT levels and histologic activity when compared to those with CR and NR.