Delayed thrombus propagation after parent artery clipping for giant fusiform aneurysms of the circle of Willis

BACKGROUND

Obliteration of a giant fusiform aneurysm without significant therapeutic morbidity is extremely difficult. Ischemic complications have been often reported.

METHODS

Two patients with giant fusiform aneurysms of the circle of Willis are presented. Both patients underwent proximal parent artery clipping after a bypass procedure. Balloon occlusion tests confirmed both patients' ability to tolerate flow reduction after proximal clipping.

RESULTS

Although both patients awoke from anesthesia without neurologic deficit, they developed contralateral hemiparesis several hours after the operation as a result of a small infarct in the basal ganglia. These ischemic events might be attributed to the delayed thrombosis involving the orifice of the distal perforating arteries.

CONCLUSIONS

In the treatment for giant fusiform aneurysms of the circle of Willis, special attention should be paid not only to flow reduction, but also to delayed thrombus propagation that may not be predicted by preoperative balloon occlusion testing.

Long-term efficacy of low-density lipoprotein apheresis on coronary heart disease in familial hypercholesterolemia. Hokuriku-FH-LDL-Apheresis Study Group

Familial hypercholesterolemia (FH) is characterized by severe hypercholesterolemia and premature coronary heart disease (CHD). The lower the plasma cholesterol level, the more likely it is that CHD can be prevented or retarded; aggressive cholesterol-lowering therapies may be indicated for FH patients with CHD. This study describes the long-term (6 years) safety and efficacy of intensive cholesterol-lowering therapies with low-density lipoprotein (LDL) apheresis in heterozygous FH patients with CHD. One hundred thirty heterozygous FH patients with CHD documented by coronary angiography had been treated by cholesterol-lowering drug therapy alone (n=87) or LDL apheresis combined with cholesterol-lowering drugs (n=43). Serum lipid levels and outcomes in each treatment group were compared after approximately 6 years. Both treatment groups had significant reductions in serum cholesterol, LDL cholesterol, and high density lipoprotein cholesterol levels. LDL apheresis significantly reduced LDL cholesterol levels from 7.42+/-1.73 to 3.13+/-0.80 mmol/L (58%) compared with group taking drug therapy, from 6.03+/-1.32 to 4.32+/-1.53 mmol/L (28%). With Kaplan-Meier analyses of the coronary events including nonfatal myocardial infarction, percutaneous transluminal coronary angioplasty, coronary artery bypass grafting, and death from CHD, the rate of total coronary events was 72% lower in the LDL-apheresis group (10%) than in drug therapy group (36%) (p=0.0088). It is concluded that LDL-apheresis is effective as treatment of CHD in FH heterozygotes, and may become the therapy of choice in severe types of FH.

Pentosidine in synovial fluid in osteoarthritis and rheumatoid arthritis: relationship with disease activity in rheumatoid arthritis

OBJECTIVE

Pentosidine is an advanced glycation endproduct formed by glycosylation and oxidation. Our aim was to develop a means to measure pentosidine in synovial fluid (SF), and to compare its concentration in SF in patients with osteoarthritis (OA) and rheumatoid arthritis (RA), and to investigate the relationship between its concentration in SF and the disease activity of RA.

METHODS

SF was collected from knee joints in 31 patients with RA and 40 with OA, who had hydrarthrosis. One patient with RA and 7 with OA who had the complication of diabetes mellitus or chronic renal failure made up the DM/CRF group, and the remaining patients made up the RA group (n = 30) and the OA group (n = 33). Pentosidine was measured by the direct HPLC method with column switching after hydrolysis of SF.

RESULTS

Pentosidine was detected in all SF and was greater in RA (83.9 +/- 46.0 nmol/l, mean +/- SD) than in OA (40.1 +/- 19.6 nmol/l). Three DM/CRF patients undergoing hemodialysis had markedly high pentosidine levels (482.5 +/- 280.8 nmol/l). There was a significant correlation between pentosidine and C-reactive protein (CRP), erythrocyte sedimentation rate, and Lansbury Index (p < 0.01). Patients with RA were divided into high and low activity groups according to the CRP and Lansbury Index. Pentosidine was significantly higher in the high activity group (CRP > or = 2.0 mg/dl and Lansbury Index > or = 50%) than in the low activity group (CRP < 2.0 and/or Lansbury Index < 50) (100.9 +/- 42.8 vs 58.5 +/- 39.6 nmol/; p = 0.0013).

CONCLUSION

Pentosidine in synovial fluid was higher in RA than in OA. Pentosidine levels in SF were related to the disease activity in RA.

Interaction of leukocytes with platelet microparticles derived from outdated platelet concentrates

Platelet microparticles (PMP) were isolated from outdated platelets by a combination of differential centrifugation and gel filtration, and the concentration of PMP was expressed in the equivalent of GPIIb/IIIa complex measured by captured ELISA. PMP bound to isolated neutrophils and macrophages in a dose-dependent manner, but they did not bind to lymphocytes. Incubation of PMP with neutrophils did not activate these cells as measured by up-regulation of Mac-1, release of human granulocyte elastase, and calcium mobilization. Incubation of PMP with macrophages did not enhance IL-8 production and the oxygen burst but slightly and significantly increased production of MCP-1. After 10 min incubation of PMP with macrophages, an increase of GPIIb/IIIa antigen was observed suggesting that PMP may be endocytosed by macrophages. In conclusion, PMP bind to leukocytes, but, in contrast to activated platelets, do not play a significant role in leukocyte activation.

Enoxaparin suppresses thrombin formation and activity during cardiopulmonary bypass in baboons

OBJECTIVE

This study tests the hypotheses that enoxaparin, a low molecular weight heparin and potent inhibitor of factor Xa, alone or in combination with standard heparin, inhibits thrombin formation and activity and modulates complement activation and neutrophil elastase release during cardiopulmonary bypass in baboons.

METHODS

After preliminary studies to determine doses and possible species differences to anticoagulants and protamine, 27 anesthesized baboons had normothermic cardiopulmonary bypass with standard, unfractionated, porcine intestinal heparin, enoxaparin, or a combination of heparin and enoxaparin. Protamine in appropriate doses was used to reverse anticoagulation. Blood samples were obtained at 6 time points. Activated clotting times were monitored; template bleeding times were measured before and up to 24 hours after cardiopulmonary bypass.

RESULTS

Hemodynamic measurements were not affected by the anticoagulant. Activated clotting times remained above 400 seconds throughout bypass, and no clots were observed. The anticoagulant did not alter platelet count, aggregation to adenosine diphosphate, release of beta-thromboglobulin, release of neutrophil elastase, or complement C3b/c and C4b/c. Enoxaparin alone, but not in combination, significantly reduced plasma levels of prothrombin fragment F1.2, fibrinopeptide A, and thrombin-antithrombin complexes but prolonged template bleeding times for more than 24 hours.

CONCLUSION

Enoxaparin significantly reduces thrombin formation and activity during cardiopulmonary bypass but does not suppress complement activation and neutrophil elastase release and is not adequately reversed by protamine after bypass.

Synthesis of a novel phosphate ester of a vitamin E derivative and its antioxidative activity

A novel phosphate ester containing a chromanol structure was synthesized from 1,2-diacyl-sn-glycero-3-phospho-2'-hydroxyethyl-2',5',7',8'-tetramethyl- 6' -hydroxychroman (PCh) by hydrolysis catalyzed by phospholipase C from Bacillus cereus. The structure of the product was found by spectral analyses to be 2-(2',5',7',8'-tetramethyl-6'-hydroxychromanyl)ethylphosphate++ + (Ch-P). Ch-P was highly soluble in the aqueous phase at neutral pH values and exerted higher antioxidative activity than alpha-tocopherol and PCh in the Fe(III)/ascorbic acid-catalyzed peroxidation of a fish oil emulsion and the autoxidation of a rat brain homogenate.

Diagnostic value of technetium-99m methoxyisobutyl isonitrile (99mTc-MIBI) scintigraphy in detecting thyroid cancer metastases: a critical evaluation

Technetium-99m methoxyisobutyl isonitrile (99mTc-MIBI) scintigraphy has recently been used in clinical application for detecting thyroid cancer metastases, its role being considered supplementary to serum thyroglobulin (Tg) measurements and radioactive iodine (131I) whole-body scans (WBS). The present retrospective study was designed to elucidate the role of 99mTc-MIBI scans in localizing metastatic lesions by assessing sensitivity and specificity of the scan results obtained in a group of 68 thyroidectomized thyroid cancer patients. Presence or absence of thyroid cancer was judged with other diagnostic modes including serum Tg measurements, 131I WBS, bone scans, chest x-rays, computed tomography (CT), ultrasonography, histopathology, and evolution of disease during follow-up. All scans were read on lesion basis for detecting neck, lung, and bone metastases and also on region basis, namely head-neck, chest, and abdomen-pelvis-extremities (ab-p-ex) areas. The sensitivity of detection was 94.4% (17/18) for neck, 78.4% (40/51) for lung, and 92.8% (64/69) for skeletal lesions. Positive predictive value (PPV) and negative predictive value (NPV) were 96.3% (26/27) and 97.7% (43/44) for head-neck; 94.7% (71/75) and 50.0% (12/24) for chest; 100.0% (25/25) and 93.1% (54/58) for ab-p-ex regions, respectively. For all scan sites taken together, PPV and NPV were 96.1% (122/127) and 86.5% (109/126), respectively. In conclusion, the present study reveals that 99mTc-MIBI can be proposed as a first-line diagnostic agent for the follow-up protocol of thyroid cancer patients, although the ability to detect small lung metastases is somewhat limited.

Cloning and nucleotide sequence of the gene encoding a serine proteinase inhibitor named marinostatin from a marine bacterium, Alteromonas sp. strain B-10-31

The gene (mstI) encoding a serine proteinase inhibitor named marinostatin from marine Alteromonas sp. strain B-10-31 was cloned and its nucleotide sequence was analyzed. A short open reading frame of 192 bp encoded 63 amino acids with a molecular weight of 6,985. Furthermore, the initial product of marinostatin (marinostatin L) was purified and its amino acid sequence was analyzed. These results indicate that marinostatin is produced as a unique precursor consisting of the mature peptide and the leader peptide for an ATP-binding cassette (ABC) transporter, and furthermore the initial product of marinostatin is dehydrated and processed by proteolysis to give homologous forms of marinostatin.

Integrin signaling: cytoskeletal complexes, MAP kinase activation, and regulation of gene expression

Members of the integrin family of adhesion receptors mediate interactions of cells with the extracellular matrix. Besides their role in tissue morphogenesis by anchorage of cells to basement membranes and migration along extracellular matrix proteins, integrins are thought to play a key role in mediating the control of gene expression by the extracellular matrix. Studies over the past 10 years have shown that integrin-mediated cell adhesion can trigger signal transduction cascades involving translocation of proteins and protein tyrosine phosphorylation events. In this review, we discuss approaches used in our lab to study early events in integrin signalling as well as further downstream changes.

[Clinical study on 6 cases of urosepsis associated with septic shock]

At Asama General Hospital, we experienced six cases of urosepsis with septic shock during a period of five years between 1989 and 1993. All six patients, whose average age was 74 years old, recovered. In four patients, the condition was caused by obstructive uropathy. The remaining two cases were caused by renal inflammatory disease, which was complicated by diabetes mellitus. One of them was renal abscess with renal papillary necrosis, and the other was emphysematous pyelonephritis. The patients, who exhibited symptoms such as gram-negative bacteremia, severe hypotension, tachycardia, decrease of urine volume and mental disturbance, were diagnosed with urosepsis with septic shock. In all cases, symptoms such as a high fever of over 39 degrees C, hypoxemia and thrombocytopenia were observed. Renal dysfunction was found in 67%, and both liver dysfunction and disseminated intravascular coagulation (DIC) were found in 50% of the cases. Since no patients suffered from adult respiratory distress syndrome, a high survival rate was apparent. Anti-shock therapy and anti-coagulation therapy were ineffective for the patients who had septic shock due to urinary tract obstruction. Urinary tract drainage was required to treat the latter patients. Nephrectomy could not be avoided in renal parenchymatous inflammatory disease. In the future, what might be essential in therapeutics against urosepsis with septic shock, particularly to avoid nephrectomy, are the treatments such as immunotherapy against endotoxins and their mediators, and hemoperfusion for the removal of endotoxins.

Long-term outcome after STA-MCA anastomosis for moyamoya disease

A long-term assessment was performed to determine the posttreatment clinical course of 113 patients with moyamoya disease. All patients sustained cerebral ischemic attacks and underwent superficial temporal artery-middle cerebral artery anastomosis with or without temporal muscle grafting. The follow-up duration was 3 to 24 years (mean 14.4 ± 5.8 [standard deviation]). Complete cessation of the ischemic episodes was obtained in 110 of 113 patients. One hundred patients were able to return to independent acitvities of daily living. Intellectual delays prevented 24 patients from engaging in an independent social life. Although intracranial bleeding is one of the common manifestations in moyamoya disease, hemorrhage was not detected in the 113 patients who underwent cerebral revascularization.

Synthesis and reactivities of 3-indocyanine-green-acyl-1,3-thiazolidine-2-thione (ICG-ATT) as a new near-infrared fluorescent-labeling reagent

A new near-infrared fluorescent-labeling reagent (ICG-ATT) bearing the 3-acyl-1,3-thiazolidine-2-thione (ATT) moiety with the chemoselective acylation feature and the dye moiety of indocyanine green (ICG) has been developed. Synthesis and reactivities of the ICG-ATT are described.

Peripheral primitive neuroectodermal tumor of the ovary confirmed by CD99 immunostaining, karyotypic analysis, and RT-PCR for EWS/FLI-1 chimeric mRNA

We report a case of peripheral primitive neuroectodermal tumor (pPNET), which belongs to the PNET/Ewing's sarcoma family, arising in the left ovary of a 29-year-old woman. Microscopically, the tumor was composed of solid nests and sheets of monotonous, primitive, small round cells with a few rosettes, making it difficult to distinguish from small cell carcinoma of the ovary. Immunohistochemically, the tumor cells showed intense cell-membranous immunoreactivity for MIC2 protein (CD99). A short-term cell culture and karyotypic analysis revealed the tumor to possess a balanced t(11;22)(q24;q12) chromosomal translocation that is highly specific for tumors of the PNET/Ewing's sarcoma family. In addition, EWS/FLI-1 chimeric mRNA that originated from the characteristic chromosomal translocation was detected by reverse transcription-polymerase chain reaction. These results confirmed the diagnostic validity of the present tumor being a pPNET, thus raising the possibility that in the past, pPNETs which have arisen in the ovary may have been mistakenly diagnosed as small cell carcinomas of the ovary.

Ventriculoatrial block during atrioventricular nodal reentrant tachycardia utilizing multiple retrograde pathways

A rare case of narrow QRS tachycardia continuing despite the occurrence of VA block is reported. Right ventricular stimulation suggested dual AV nodal physiology. The tachycardia was induced by ventricular premature stimulation, which failed to depolarize the atrium. Two types of tachycardia that had different retrograde conduction sequences, HA intervals, and cycle lengths were induced. The occurrence of VA block did not terminate the tachycardia but transiently prolonged the tachycardia cycle length. These findings suggest the mechanism is AV nodal reentry utilizing multiple retrograde pathways with intranodal reentry bridging the VA block and maintaining the tachycardia.

Detection of diaphragmatic defect as the cause of severe hepatic hydrothorax with magnetic resonance imaging

Severe right-sided hepatic hydrothorax occurred in an 83-yr-old Japanese woman with a 7-yr history of cryptogenic liver cirrhosis. Transdiaphragmatic communication was indirectly suggested by rapid migration of dye (indocyanine green) from the peritoneal to the pleural space. Magnetic resonance imaging studies also demonstrated a diaphragmatic defect as a characteristic hypointense jet flow across the diaphragm on both T1- and T2-weighted sagittal scans. Although no firm treatment for hepatic hydrothorax has been established and direct demonstration of diaphragmatic defect with noninvasive imaging is extremely rare, testing for diaphragmatic integrity is meaningful to provide a radical or less invasive treatment. Magnetic resonance imaging, as well as color Doppler ultrasonography, may be useful for the detection of diaphragmatic defects as the cause of hepatic hydrothorax.

Fibronectin and integrins in cell adhesion, signaling, and morphogenesis

Fibronectin and integrins play crucial roles in a variety of morphogenetic processes, in which they mediate cell adhesion, migration, and signal transduction. They induce hierarchical transmembrane organization of cytoskeletal and signaling molecules into multimolecular complexes of more than 30 proteins. Organization of these complexes is a synergistic process dependent on integrin aggregation and occupancy, as well as tyrosine phosphorylation. Integrins also cooperate with growth-factor receptors to enhance signaling. Fibronectin and integrins induce a variety of downstream effects, including enhanced transcription factor activity, induction of over 30 genes (> half novel), and altered expression of over 100 proteins. Fibronectin and integrins therefore trigger a hierarchy of signaling responses involved in regulating processes crucial for normal morphogenesis, including cell adhesion, migration, and specific gene expression.

Changes in bone mineral density after orchidectomy and hormone replacement therapy in individuals with androgen insensitivity syndrome

Changes in bone mineral density (BMD) after orchidectomy and after hormone replacement therapy were reported in two patients with complete androgen insensitivity syndrome (AIS). Diagnosis of AIS was made by clinical features and confirmed by the presence of 46,XY karyotype and the presence of testis component in the removed gonads. BMD at the lumbar spine and at three sites of the femur was measured by dual energy X-ray absorptiometry (DXA). The Z scores of the lumbar spine BMD before orchidectomy were -0.8 and -3.1, confirming that patients with AIS have low BMD and that androgen plays an important role in bone mineralization in 46,XY individuals. Castration reduced BMD, but treatment with daily doses of 1.25 mg of conjugated oestrogen and 10 mg of medroxyprogesterone acetate increased BMD. These results indicate that both oestrogen and androgen play an important role in balancing BMD in men.

Actin-filaments localize on the sorting endosomes of 3Y1 fibroblastic cells

By immunofluorescence microscopic observation, monoclonal and polyclonal antibodies against a synthetic actin C-terminal peptide were found to stain too colloguial, ambiguous punctuate structures distributed throughout the cytoplasm of 3Y1 cells, independently of actin stress fibers. Antibody against rab5, a small GTP binding protein of the sorting endosome, and anti-actin antibody co-stained these punctuate structures. On the other hand, transferrin receptor, a well characterized maker of the sorting and recycling endosomes, colocalized with actin on the vesicular structures at the cell peripheral region but not at the perinuclear area where the recycling endosome localized. These observations suggest that actin molecules localize on the sorting endosomes. Tropomyosin, F-actin binding protein, also colocalized with actin on the sorting endosomes. From these results, we proposed that actin-filaments with tropomyosin constitute the membrane skeleton on the sorting endosome surface. This article is the first report to show that actin-filaments localize on the intact endosomes.

Characteristic difference in gastrointestinal excretion of clarithromycin and roxithromycin

Excretion characteristics of two new macrolides; clarithromycin and roxithromycin, into the intestinal and the gastric lumens was studied by in situ single-pass perfusion and loop methods in rats. Roxithromycin maintained higher serum levels than clarithromycin after their intravenous administrations at a dose of 5 mg kg(-1) each. Radioactivities of clarithromycin and roxithromycin exsorbed into the intestinal lumen were 8.6 and 18.9% of dose in 2 h, respectively, whereas clarithromycin and roxithromycin excreted into the bile were 28.4 and 5.9%, respectively. These results suggest that roxithromycin is transported mainly by exsorption across the intestinal membrane, whereas clarithromycin mainly by excretion through the biliary tract. On the other hand, radioactivities of clarithromycin and roxithromycin exsorbed into the gastric lumen were much less then those into the intestinal lumen and were 0.72 and 1.34% of dose in 4 h, respectively. Thus, the exsorption into the gastric lumen seems to be a minor route for the elimination of both macrolides. Consequently, the transport into the intestinal lumen via the intestinal membrane and/or the bile tract may play a significant role in the overall elimination of both macrolides.

Role of transforming growth factor-beta1 in the pathogenesis of moyamoya disease

OBJECT

Prominent features of moyamoya disease are intimal thickening of the cerebral arterial trunks and abundant angiogenesis for collateral blood supplies, but its pathogenesis is still unknown. The aim of this study was to test the possibility that transforming growth factor-beta1 (TGFbeta1) may play a role in the pathogenesis of moyamoya disease.

METHODS

The authors used reverse transcription-polymerase chain reaction to analyze the expression level of TGFbeta1 in smooth-muscle cells cultured from the superficial temporal arteries (STAs) and measured the serum level of TGFbeta1 by using enzyme-linked immunosorbent assay. Although the STA is not predominantly involved with moyamoya disease, it has been used in studies of the pathogenesis of this disease. In this report, the STAs from six patients with moyamoya disease and four with arteriosclerotic cerebrovascular disease, along with sera from 14 patients with moyamoya disease and 10 normal healthy volunteers, were studied. The expression of TGFbeta1 was significantly higher in cultured smooth-muscle cells derived from the STAs of patients with moyamoya disease than in those derived from the STAs of patients with arteriosclerotic cerebrovascular disease (p < 0.05). The serum level of TGFbeta1 was also significantly higher in patients with moyamoya disease than in controls (p < 0.0005).

CONCLUSIONS

Taking into account the functional roles of TGFbeta1 in the expression of connective tissue genes and angiogenesis, these investigators suggest that TGFbeta1 is associated with the pathogenesis of moyamoya disease, including abundant neovascularization, although their findings do not necessarily mean that TGFbeta1 is a causative factor in this disease.

Comparison of bone regeneration in a rabbit skull defect by recombinant human BMP-2 incorporated in biodegradable hydrogel and in solution

The objective of this study is to compare bone regeneration induced by recombinant human bone morphogenetic protein-2 (rhBMP-2) incorporated into a biodegradable gelatin hydrogel with that by rhBMP-2 in aqueous solution. After treating rabbit skull defects of 6 mm diameter with the two rhBMP-2 dosage forms, both of them increased the bone mineral density (BMD) at the skull defects with implantation time to a significantly higher extent than a rhBMP-2-free aqueous solution and a rhBMP-2-free empty gelatin hydrogel (p < 0.05). There was no quantifiable difference in BMD between the two dosage forms of rhBMP-2. Histological examination revealed that the integrity of newly generated bone increased with the rhBMP-2 dose, irrespective of the dosage form. The bone defect was filled with regenerated bone 21 days after treatment.

Erythropoietin mRNA in hepatocellular carcinomas and kidney in male B6C3F1 mice with secondary polycythemia

The purpose of this study was to investigate the cause of polycythemia occurring in hepatocellular carcinoma-bearing control male B6C3F1 mice from 2-yr carcinogenicity studies. Erythrocyte counts and plasma levels of erythropoietin in mice with hepatocellular carcinomas were significantly increased compared with the values in non-tumor-bearing mice. Erythropoietin mRNA in 4 of 5 non-tumor-bearing mice was detected in the kidney, but no visible signals for hepatic erythropoietin mRNA in 5 of 5 non-tumor-bearing mice were detected by the reverse transcriptase competitive polymerase chain reaction method. Erythropoietin mRNA was expressed in neoplastic hepatocytes from 8 of 9 hepatocellular carcinoma-bearing mice, and this expression was accompanied by decreased expression of erythropoietin mRNA in the kidneys from these mice. The present findings show that polycythemia in hepatocellular carcinoma-bearing mice occurs secondary to excess synthesis of erythropoietin mRNA by neoplastic hepatocytes.