High-Fructose Diet-Induced Hypertriglyceridemia Is Associated With Enhanced Hepatic Expression of ACAT2 in Rats

High levels of fructose induce hypertriglyceridemia, characterized by excessive levels of triglyceride-rich lipoproteins such as very low-density lipoprotein (VLDL); however, the underlying mechanisms are poorly understood. The aim of this short communication was to examine hepatic changes in the expression of genes related to cholesterol metabolism in rats with hypertriglyceridemia induced by high-fructose or high-glucose diets. Rats were fed a 65 % (w/w) glucose diet or a 65 % (w/w) fructose diet for 12 days. Serum levels of triglycerides, total cholesterol, and VLDL+LDL-cholesterol, hepatic levels of triglycerides and cholesterol, and ACAT2 expression at the gene and protein levels were significantly higher in the fructose diet group compared to the glucose diet group. The hepatic levels of Abcg5/8 were lower in the fructose group than in the glucose group. Serum high-density lipoprotein (HDL)-cholesterol and hepatic expression levels of Hmgcr, Ldlr, Acat1, Mttp, Apob, and Cyp7a1 did not differ significantly between groups. These findings suggest that high-fructose diet-induced hypertriglyceridemia is associated with increased hepatic ACAT2 expression.

Frequent somatic mutations in epigenetic regulators in newly diagnosed chronic myeloid leukemia

Although tyrosine kinase inhibitors (TKIs) have significantly improved the prognosis of chronic myeloid leukemia (CML), the ability of TKIs to eradicate CML remains uncertain and patients must continue TKI therapy for indefinite periods. In this study, we performed whole-exome sequencing to identify somatic mutations in 24 patients with newly diagnosed chronic phase CML who were registered in the JALSG CML212 study. We identified 191 somatic mutations other than the BCR-ABL1 fusion gene (median 8, range 1–17). Age, hemoglobin concentration and white blood cell counts were correlated with the number of mutations. Patients with mutations ⩾6 showed higher rate of achieving major molecular response than those<6 (P=0.0381). Mutations in epigenetic regulator, ASXL1, TET2, TET3, KDM1A and MSH6 were found in 25% of patients. TET2 or TET3, AKT1 and RUNX1 were mutated in one patient each. ASXL1 was mutated within exon 12 in three cases. Mutated genes were significantly enriched with cell signaling and cell division pathways. Furthermore, DNA copy number analysis showed that 2 of 24 patients had uniparental disomy of chromosome 1p or 3q, which disappeared major molecular response was achieved. These mutations may play significant roles in CML pathogenesis in addition to the strong driver mutation BCR-ABL1.

MAPKs, activator protein-1 and nuclear factor-κB mediate production of interleukin-1β-stimulated cytokines, prostaglandin E₂ and MMP-1 in human periodontal ligament cells

BACKGROUND AND OBJECTIVE

Determination of the interleukin-1 (IL-1) signaling cascades that lead to the production of various inflammatory mediators and catabolic factors may clarify attractive targets for therapeutic intervention for periodontitis. We comprehensively assessed the involvement of MAPKs, activator protein-1 (AP-1) and nuclear factor-κB (NF-κB) in IL-1β-induced production of interleukin-6 (IL-6), interleukin-8 (IL-8), prostaglandin E(2) (PGE(2) ) and MMP-1 in human periodontal ligament cells.

MATERIAL AND METHODS

Human periodontal ligament cells were pretreated with an inhibitor for each of the MAPKs or NF-κB and subsequently treated with IL-1β. Following treatment, phosphorylation of three types of MAPK (ERK, p38 MAPK and c-Jun N-terminal kinase), IκB kinase (IKK) α/β/γ and IκB-α, as well as the DNA binding activity of AP-1 and NF-κB and the production of IL-6, IL-8, PGE(2) and MMP-1, were determined by western blotting, a gel mobility shift assay and ELISA, respectively.

RESULTS

The three MAPKs, simultaneously activated by IL-1β, mediated the subsequent DNA binding of AP-1 at various magnitudes, while IKKα/β/γ, IκB-α and NF-κB were also involved in the IL-1 signaling cascade. Furthermore, IL-1β stimulated the production of IL-6, IL-8, PGE(2) and MMP-1 via activation of the three MAPKs and NF-κB, because inhibitors of these significantly suppressed the IL-1β-stimulated production of these factors.

CONCLUSION

Our results strongly suggest that MAPK, AP-1 and NF-κB mediate the IL-1β-stimulated synthesis of IL-6, IL-8, PGE(2) and MMP-1 in human periodontal ligament cells. Therefore, inhibition of activation of MAPK, AP-1 and/or NF-κB may lead to therapeutic effects on progression of periodontitis.

CMC-544 (inotuzumab ozogamicin), an anti-CD22 immuno-conjugate of calicheamicin, alters the levels of target molecules of malignant B-cells

We studied the effect of CMC-544, the calicheamicin-conjugated anti-CD22 monoclonal antibody, used alone and in combination with rituximab, analyzing the quantitative alteration of target molecules, that is, CD20, CD22, CD55 and CD59, in Daudi and Raji cells as well as in cells obtained from patients with B-cell malignancies (BCM). Antibody inducing direct antiproliferative and apoptotic effect, complement-dependent cytotoxicity (CDC) and antibody-dependent cellular cytotoxicity (ADCC) were tested separately. In Daudi and Raji cells, the CDC effect of rituximab significantly increased within 12 h following incubation with CMC-544. The levels of CD22 and CD55 were significantly reduced (P<0.001 in both cells) after incubation with CMC-544, but CD20 level remained constant or increased for 12 h. Similar results were obtained in cells from 12 patients with BCM. The antiproliferative and apoptotic effect of CMC-544 were greater than that of rituximab. The ADCC of rituximab was not enhanced by CMC-544. Thus, the combination of CMC-544 and rituximab increased the in vitro cytotoxic effect in BCM cells, and sequential administration for 12 h proceeded by CMC-544 was more effective. The reduction of CD55 and the preservation of CD20 after incubation with CMC-544 support the rationale for the combined use of CMC-544 and rituximab.

On-site treatment of turbid river water using chitosan, a natural organic polymer coagulant

Chitosan, acetylate of chitin, is a biodegradable cationic polymer. The objective of this study is to assess the applicability of chitosan as an on-site treatment agent of turbid water caused by river construction works and other diffused pollutions. The results of jar-tests indicate that floc of chitosan is much larger than that of aluminium sulfate, and turbidity treated by chitosan under moving water conditions is much lower than that of aluminium sulfate. Chitosan is applied to Imou River in Yamaguchi prefecture, where river construction work is going on. St.1 is located just below the construction work, St.2 is located about 250 m downstream from St.1, and St.3 is located about 350 m downstream from St.2. Initial turbidity of each station is 1,100, 937 and 313 NTU, respectively. By applying chitosan at St.1, turbidity of each station is drastically reduced to 1,100, 12 and 0 NTU. Chitosan could be helpful to reduce problems caused by turbidity in rivers.

Efficacy of gemtuzumab ozogamicin on ATRA- and arsenic-resistant acute promyelocytic leukemia (APL) cells

Acute promyelocytic leukemia (APL) cells express a considerable level of CD33, which is a target of gemtuzumab ozogamicin (GO), and a significantly lower level of P-glycoprotein (P-gp). In this study, we examined whether GO was effective on all-trans retinoic acid (ATRA)- or arsenic trioxide (ATO)-resistant APL cells. Cells used were an APL cell line in which P-gp was undetectable (NB4), ATRA-resistant NB4 (NB4/RA), NB4 and NB4/RA that had been transfected with MDR-1 cDNA (NB4/MDR and NB4/RA/MDR, respectively), ATO-resistant NB4 (NB4/As) and blast cells from eight patients with clinically ATRA-resistant APL including two patients with ATRA- and ATO-resistant APL. The efficacy of GO was analyzed by (3)H-thymidine incorporation, the dye exclusion test and cell cycle distribution. GO suppressed the growth of NB4, NB4/RA and NB4/As cells in a dose-dependent manner. GO increased the percentage of hypodiploid cells significantly in NB4, NB4/RA and NB4/As cells, and by a limited degree in NB4/MDR and NB4/RA/MDR cells. Similar results were obtained using blast cells from the patients with APL. GO is effective against ATRA- or ATO-resistant APL cells that do not express P-gp, and the mechanism of resistance to GO is not related to the mechanism of resistance to ATRA or ATO in APL cells. Leukemia (2005) 19, 1306-1311. doi:10.1038/sj.leu.2403807; published online 26 May 2005.

Preservation of baroreflex control of vascular resistance under ketamine anesthesia in rats

The aim of this study was to examine the effects of ketamine and pentobarbital on the baroreceptor reflex control of vascular resistance in rats. The gains of baroreflex were assessed by relating changes in arterial pressure to changes in hindlimb perfusion pressure, using an extracorporeal perfusion circuit with a delay system. Reflex-induced vasodilation or vasoconstriction in response to a rise or a fall in arterial pressure were elicited by injections of phenylephrine or nitroprusside, respectively. The gains of baroreflex were not altered by ketamine 1 and 5 mg/kg (i.v.), whereas those were depressed by pentobarbital 5 mg/kg (i.v.). The results suggest that ketamine preserves the baroreflex control of vascular resistance and pentobarbital depresses it. The preservation of the baroreflex control of vascular resistance may be advantageous for patients with hypovolemia to sustain the blood pressure.

Antimonocyte chemoattractant protein-1 gene therapy reduces experimental in-stent restenosis in hypercholesterolemic rabbits and monkeys

In-stent restenosis results exclusively from neointimal hyperplasia due to mechanical injury and a foreign body response to the prosthesis. Inflammation mediated by monocyte chemoattractant protein-1 (MCP-1) might therefore underlie in-stent restenosis. We recently devised a new strategy for anti-MCP-1 gene therapy by transfecting an N-terminal deletion mutant of the MCP-1 gene into skeletal muscles. We used this strategy to investigate the role of MCP-1 in experimental in-stent restenosis in hypercholesterolemic rabbits and monkeys. Transfection of the mutant MCP-1 gene suppressed monocyte infiltration/activation in the stented arterial wall and markedly reduced the development of neointimal hyperplasia. This strategy also suppressed local expression of MCP-1 and inflammatory cytokines. Therefore, inhibition of MCP-1-mediated inflammation is effective in reducing experimental in-stent restenosis. This strategy might be a useful form of gene therapy against human in-stent restenosis.

Analysis of pathological risk factors for lymph node metastasis of submucosal invasive colon cancer

There are currently no universally accepted indications and criteria for additional surgical resection of the colorectum after endoscopic resection of the submucosal invasive cancer. The purpose of the present study is to establish accurate indications and criteria for additional surgical resection of the colorectum, based on the prediction of lymph node metastasis, after endoscopic resection of the submucosal invasive cancer. We investigated 140 submucosal invasive colorectal cancers and analyzed the pathologic factors of lymph node metastasis. The tumors were evaluated for pathologic factors in the invasive area of the submucosal carcinoma and were compared between the cases with lymph node metastasis and those without lymph node metastasis. Lymph node metastasis was observed in 13 cases (9%). Univariate logistic regression analysis showed that the depth of invasion, cribriform-type structural atypia, absence of lymphoid infiltration, lymphatic permeation, and venous permeation were statistically significant as risk factors for lymph node metastasis. Multivariate logistic regression analysis showed that the important risk factors included, in decreasing order, lymphatic permeation, absence of lymphoid infiltration, cribriform-type structural atypia, venous permeation, and depth of invasion. Submucosal invasion of 2 mm or more, and/or, depth of lymphatic permeation of 2 mm or more are risk factors for lymph node metastasis. The pathologic criteria based on our results for additional colectomy enables greater accuracy selection of patients who will undergo further surgical treatment after endoscopic resection.

Delayed adverse reactions to iodinated radiographic contrast media after coronary angiography: a search for possible risk factors

OBJECTIVE

The incidence of and risk factors for delayed adverse events (DAEs) that appear from 1 h to 7 days after injection of radiographic contrast media were investigated in patients who had undergone coronary angiography (CAG).

METHODS

DAEs were monitored by questionnaire in 155 patients who received iomeprol. Isosorbide dinitrate was injected in every case. Risk factors for DAEs were analysed by a logistic regression model.

RESULTS

Of 118 patients who returned questionnaires, 54 complained of DAEs, although no severe or fatal reactions occurred. Erythema, rash and nausea were frequent events. Female gender, total dose of isosorbide dinitrate <2 mg, and execution of acetylcholine provocation test were found to be the major risk factors, and the incidence of DAEs increased as the number of risk factors increased.

CONCLUSION

Care should be taken when CAG is performed on female patients who undergo acetylcholine provocation tests and receive low-dose nitric oxide donor injections.

Inhibition of neointimal hyperplasia after balloon injury by cis-element 'decoy' of early growth response gene-1 in hypercholesterolemic rabbits

Early growth response factor-1 (Egr-1) is a transcription factor that is rapidly activated after vascular injury and thus might contribute to vascular proliferation and inflammation. We hypothesized that Egr-1 might therefore be a therapeutic target against restenosis. Hypercholesterolemic rabbits were intraluminally administered synthetic DNA as a 'decoy' against Egr-1 immediately after carotid artery balloon injury. Efficient transfection was confirmed by the delivery of a fluorescence-labeled decoy. Gel mobility-shift assay showed increased Egr-1 activity after balloon injury and its prevention by Egr-1 decoy transfection in vivo. Egr-1 decoy transfection attenuated early inflammation and proliferation and later neointimal hyperplasia. In addition, Egr-1 decoy transfection reduced gene expression and protein production of Egr-1-dependent genes such as platelet-derived growth factor-B, transforming growth factor-beta1, and monocyte chemoattractant protein-1. The Egr-1 pathway has an essential role in the pathogenesis of neointimal hyperplasia after balloon injury in hypercholesterolemic rabbits. This decoy strategy is a potential practical form of therapy for human restenosis.

Serum lipid profiles in Japanese women and men during consumption of walnuts

OBJECTIVE

To determine the serum cholesterol, apolipoproteins and LDL oxidizability in young Japanese women and men during walnut consumption and to evaluate its active principle.

DESIGN

Experimental study with a randomized design.

SUBJECTS

Twenty healthy women and 20 healthy men.

INTERVENTIONS

Subjects were randomly assigned to consume each of two mixed natural diets for 4 weeks in a cross-over design. Reference and walnut diets were designed and the walnut diet had 12.5% of the energy derived from walnuts (44-58 g/day).

RESULTS

The total cholesterol and serum apolipoprotein B concentrations, and the ratio of LDL cholesterol to HDL cholesterol was significantly lowered in women and men when fed on the walnut diet, than when on the reference diet (P<or=0.05). The LDL cholesterol concentration was significantly lowered in women on the walnut diet (0.22 mmol/l, P=0.0008), whereas this decrease was not significant in men (0.18 mmol/l, P=0.078). The most prominent change in the fatty acid composition of the cholesteryl esters from serum after the walnut diet was an elevation of alpha-linolenic acid in women (76%, P<0.001) and men (107%, P<0.001). This elevation was negatively correlated to the change in LDL cholesterol in women (r=0.496, P=0.019) and men (r=0.326, P=0.138). The LDL oxidizability in women was not influenced by the diets (P=0.19).

CONCLUSIONS

alpha-Linolenic acid in the walnut diet appears to be responsible for the lowering of LDL cholesterol in women.

SPONSORSHIP

Kyushu University (Fukuoka, Japan) and the California Walnut Commission (California, USA).

Reduced effect of gemtuzumab ozogamicin (CMA-676) on P-glycoprotein and/or CD34-positive leukemia cells and its restoration by multidrug resistance modifiers

Gemtuzumab ozogamicin (CMA-676), a calicheamicin-conjugated humanized anti-CD33 mouse monoclonal antibody, has recently been introduced clinically as a promising drug for the treatment of patients with acute myeloid leukemia (AML), more than 90% of which express CD33 antigen. However, our recent study suggested that CMA-676 was excreted by a multi- drug-resistance (MDR) mechanism in P-glycoprotein (P-gp)-expressing leukemia cell lines. We analyzed the in vitro effects of CMA-676 on leukemia cells from 27 AML patients in relation to the amount of P-gp, MDR-associated protein 1 (MRP1), CD33 and CD34, using a multi-laser-equipped flow cytometer. The cytocidal effect of CMA-676, estimated by the amount of hypodiploid portion on cell cycle, was inversely related to the amount of P-gp estimated by MRK16 monoclonal antibody (P = 0.004), and to the P-gp function assessed by intracellular rhodamine-123 accumulation in the presence of PSC833 or MS209 as a MDR modifier (P = 0.0004 and P = 0.002, respectively). In addition, these MDR modifiers reversed CMA-676 resistance in P-gp-expressing CD33(+) leukemia cells (P = 0.001 with PSC833 and P = 0.0007 with MS209). In CD33(+) AML cells from 13 patients, CMA-676 was less effective on CD33(+)CD34(+) than CD33(+)CD34(-) cells (P = 0.002). PSC833 partially restored the effect of CMA-676 in CD33(+)CD34(+) cells. These results suggest that the combined use of CMA-676 and a MDR modifier will be more effective on CD33(+) AML with P-gp-related MDR.

Arsenic trioxide therapy for relapsed or refractory Japanese patients with acute promyelocytic leukemia: need for careful electrocardiogram monitoring

Recent studies have shown that arsenic trioxide (As(2)O(3)) can induce complete remission in patients with acute promyelocytic leukemia (APL). We tested the efficacy and safety of As(2)O(3) for the treatment of patients with APL who had relapsed from or become refractory to all-trans retinoic acid (ATRA) and conventional chemotherapy in a prospective study. As(2)O(3) at a dose of 0.15 mg/kg was administered until the date of bone marrow remission to a maximum of 60 days. In patients who achieved complete remission (CR), one additional course of As(2)O(3) was administered using the same dose for 25 days. Of 14 patients, 11 (78%) achieved CR. Six of 10 patients who achieved CR showed disappearance of PML-RARalpha transcript by RT-PCR assay. The duration of As(2)O(3)-induced CR ranged from 4 to 22 months (median, 8 months) at a median follow-up of 17 months. Adverse events included 13 electrocardiogram abnormalities (13 QTc prolongation, eight ventricular premature contraction, four nonsustained ventricular tachycardia and two paroxysmal supraventricular tachycardia), seven nausea and vomiting, four pruritus, three peripheral neuropathy, three fluid retention and one APL differentiation syndrome. Four patients received antiarrhythmic agents. Hyperleukocytosis developed in five patients and in three cytotoxic drugs were necessary. Other adverse events were relatively mild. As(2)O(3) treatment is effective and relatively safe in relapsed or refectory patients with APL. Cardiac toxicities in patients with QTc prolongation should be carefully monitored.

15-Deoxy-delta 12,14-prostaglandin J2 and thiazolidinediones activate the MEK/ERK pathway through phosphatidylinositol 3-kinase in vascular smooth muscle cells

Peroxisome proliferator-activated receptor (PPAR) gamma belongs to the nuclear receptor superfamily of ligand-dependent transcription factors. Recent results have shown that the ligands for nuclear receptors have rapid effects so called "nongenomic" effects, which are observed within minutes after stimulation. We examined whether 15-deoxy-Delta(12,14)-prostaglandin J(2) (15-d-PGJ2) had rapid effects on cultured vascular smooth muscle cells. Phosphorylation of ERK and c-fos mRNA expression were determined by Western and Northern blot analyses, respectively. PPAR gamma agonists 15-d-PGJ2 and thiazolidinediones such as pioglitazone and troglitazone elicited rapid activation of ERK within 15 min and induced c-fos mRNA expression within 30 min, whereas the PPAR alpha agonist bezafibrate failed to activate ERK. 15-d-PGJ2-induced expression of c-fos mRNA was blocked by PD98059 or U0126, two ERK kinase inhibitors, suggesting that the MEK/ERK pathway mediates 15-d-PGJ2-induced c-fos gene expression. Furthermore, pretreatment with wortmannin, an inhibitor of phosphatidylinositol 3 (PI3)-kinase, inhibited 15-d-PGJ2-induced ERK activation and c-fos mRNA expression, suggesting that PI3-kinase is involved in the process. An electrophoretic mobility shift assay showed that 15-d-PGJ2 enhanced AP-1 binding activity to AP-1 consensus sequence in a time-dependent manner. 15-d-PGJ2 increased thymidine incorporation in a PI3-kinase-dependent manner. Taken together, our findings show that 15-d-PGJ2 and thiazolidinediones activate the MEK/ERK pathway through PI3-kinase and lead to c-fos mRNA expression and DNA synthesis. These findings indicate a novel regulatory mechanism of gene expression by 15-d-PGJ2 and thiazolidinediones.

Role of P-glycoprotein in all-trans retinoic acid (ATRA) resistance in acute promyelocytic leukaemia cells: analysis of intracellular concentration of ATRA

We analysed the relationship between all-trans retinoic acid (ATRA) resistance and P-glycoprotein (P-gp)-associated multidrug resistance (MDR) in acute promyelocytic leukaemia (APL). There was no difference in the intracellular ATRA accumulation between NB4 cells and an MDR1 cDNA-transduced NB4 subline and between ATRA-resistant NB4 cells (NB4/RA) and an MDR1 cDNA-transduced NB4/RA subline. PSC833, a MDR modifier, did not increase the intracellular accumulation of ATRA or affect the expression of CD11b, the nitroblue tetrazolium (NBT) reduction activity, the proportion of apoptotic cells or the morphology of these four ATRA-treated cell lines. Similar results were obtained in the analysis of APL cells from five patients relapsed after ATRA-induced complete remission.

8-oxo-dGTPase, which prevents oxidative stress-induced DNA damage, increases in the mitochondria from failing hearts

BACKGROUND

Reactive oxygen species (ROS) can cause an oxidative modification of nucleotides, such as 8-oxo-7,8-dihydrodeoxyguanosine triphosphate (8-oxo-dGTP), which can lead to defects in DNA replication. The misincorporation of 8-oxo-dGTP into DNA is prevented by 8-oxo-dGTPase, which hydrolyzes 8-oxo-dGTP into 8-oxo-dGMP. The changes in this defensive system have not yet been examined in failing hearts, in which the generation of ROS increases.

METHODS AND RESULTS

Myocardial infarction (MI) was created in mice by ligating the left coronary artery. Four weeks later, the left ventricle was dilated and contractility was diminished on echocardiography. The generation of ROS, as measured by electron spin resonance spectroscopy with 4-hydroxy-2,2,6,6-tetramethyl-piperidine-N-oxyl, increased in the noninfarcted left ventricle from MI mice. The formation of thiobarbituric acid-reactive substances also increased in the mitochondria from MI mice. 8-Oxo-dGTPase was detected in the mitochondrial fractions isolated from MI mice using a Western blot analysis with an antibody to its human homologue (hMTH1). Immunohistochemistry showed positive staining for hMTH1 was localized in the cardiac myocytes.

CONCLUSIONS

The level of 8-oxo-dGTPase increased in the mitochondria isolated from post-MI hearts as oxidative stress increased, thus suggesting that a preventive mechanism is activated against ROS-induced DNA damage. As a result, 8-oxo-dGTPase is considered a useful marker of mitochondrial oxidative stress in heart failure.

Electropharmacologic effects of pilsicainide, a pure sodium channel blocker, on the remodeled atrium subjected to chronic rapid pacing

Clinical experience suggests that sodium channel blockers are effective in converting atrial fibrillation of recent onset but not chronic atrial fibrillation. We investigated changes in the electrophysiologic effects of pilsicainide, a pure sodium channel blocker, on the canine atrium during chronic rapid pacing (400/min). Three pairs of bipolar electrodes were sutured to the right atrial appendage in six dogs. Five days later, rapid atrial pacing was started after baseline measurements of the effective refractory period (ERP), the intra-atrial conduction velocity, the atrial wavelength, and the inducibility of atrial fibrillation. These studies were repeated at 2, 7, and 14 days of pacing, both before and after pilsicainide administration. Before pacing, pilsicainide increased ERP more than it decreased conduction velocity, causing an increase of wavelength, particularly at faster rates. However, this use-dependent prolongation of ERP disappeared after 2 days of pacing. Thus, pilsicainide failed to prolong ERP during chronic pacing, allowing progressive shortening of wavelength in the remodeled atrium. The effect of sodium channel blockers on atrial refractoriness may decline as rapid atrial excitation persists, limiting the usefulness of these agents for the treatment of chronic atrial fibrillation.

Coronary revascularization in Japan. Part 1: survey of facilities during 1997

Coronary artery disease is one of the major causes of morbidity and mortality in industrialized countries, including Japan. Increasing numbers of patients have been treated with percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG), but there is little information in Japan concerning the use of revascularization therapy and the facilities. The Japanese Coronary Intervention Study (JCIS) Group conducted a nationwide survey on coronary revascularization procedures and facilities during 1997. A questionnaire was mailed to the presidents or designated delegates of 8,253 laboratories in 7,986 hospitals that had departments of internal medicine and/or cardiovascular medicine and to 578 facilities in 558 hospitals identified by the PCI survey as performing CABG and/or registered in the annual survey carried out by the Japanese Association for Thoracic Surgery. A total of 109,788 PCIs were performed at 1,023 laboratories, and 17,667 CABGs at 477 facilities. PCI and CABG numbers per 10(6) population were 870 and 140, respectively. The ratio of PCI to CABG was 6.2. The numbers of PCI laboratories and CABG facilities per 10(6) population were 8.1 and 3.8, respectively. The majority of PCI laboratories and CABG facilities had a small annual volume: 44% of PCI laboratories and 77% of CABG facilities had annual volumes of 50 or less. Only half of the PCI laboratories had surgical backup on-site. Despite the small volume for each facility, coronary revascularization, especially PCI, is highly utilized in Japan.

Increased inactivation of nitric oxide is involved in impaired coronary flow reserve in heart failure

Recent evidence suggests that increased inactivation of endothelium-derived nitric oxide (NO) by oxygen free radical (OFR) formation is involved in the pathogenesis of endothelial dysfunction in heart failure (HF). However, it is unclear whether increased OFR limits coronary flow reserve in HF. To test this hypothesis, we examined the effects of antioxidant therapy on coronary flow reserve in a canine model of tachycardia-induced HF. The flow reserve (percent increase in coronary blood flow) to adenosine or to 20-s ischemia was less and OFR formation (electron-spin resonance spectroscopy) in myocardial tissues was greater in HF dogs than in controls. Immunohistochemical staining of 4-hydroxy-2-nonenal, an OFR-induced lipid peroxide, was detected in coronary microvessels of HF dogs. Intracoronary infusion of a cell-permeable OFR scavenger, tiron, suppressed OFR formation and improved the vasodilating capacity to adenosine or brief ischemia in HF dogs but not in controls. A NO synthesis inhibitor, N(G)-monomethyl-L-arginine (L-NMMA), diminished the beneficial effects of tiron in HF dogs. Vasodilation to sodium nitroprusside was similar between control and HF dogs, and no change in its response was noted with tiron or tiron + L-NMMA in either group. In summary, antioxidant treatment with tiron improved coronary flow reserve by increasing NO bioactivity in HF dogs. Thus increased OFR formation may impair coronary flow reserve in HF by reducing NO bioactivity.

Coronary revascularization in Japan. Part 2: comparison of facilities between 1997 and 1999

A nation-wide survey on the procedures and facilities of coronary revascularization, percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) conducted by the Japanese Coronary Intervention Study (JCIS) group during 1997 revealed that PCI is more often used than CABG and is mainly carried out in low-volume facilities without surgical backup. The present study aimed to investigate the temporal changes in the usage of revascularization therapies and facilities from 1997 to 1999. A questionnaire was mailed in 1998 to the delegates of 1,086 PCI and 582 CABG facilities identified by the previous survey, and 89% of PCIs surveyed and 94% of CABGs surveyed reported back. The number of PCI procedures had increased by 19% from 97,831 to 116,479 and that of CABG procedures also increased by 21% from 16,374 to 19,846. The ratio of PCI to CABG was 5.9 in 1999, showing no significant change from 6.0 in 1997. In parallel, the number of PCI and CABG facilities increased from 888 to 941 and from 442 to 453, respectively. The use of coronary stents and other interventional devices increased during these 2 years. Coronary stents were used regardless of the annual procedural volume of the facilities, whereas other interventional devices, directional and rotational coronary atherectomy, were used mainly in the high-volume laboratories (p<0.01). Beating-heart, off-pump CABG had increased from 2% to 11% of total cases. Continued monitoring of trends in PCI and CABG facilities and procedures will be needed for nation-wide assessment of the use of new technology.

Three-year follow-up of the Japanese patients with microvascular angina attributable to coronary microvascular spasm

BACKGROUND

We recently reported that coronary microvascular spasm could cause angina in patients with chest pain and normal coronary arteriograms. However, the long-term prognosis of these patients or the effect of calcium channel blockers is not known.

METHODS

Of consecutive 283 patients who underwent acetylcholine testing for the evaluation of chest pain, we identified 68 patients with microvascular angina attributable to coronary microvascular spasm. All patients were discharged on calcium channel blockers and followed up for an average period of 3.3 years.

RESULTS

As compared with those having epicardial spasm (n=169), there was a female predominance in the microvascular spasm group (P<0.01), and 81% of the female patients were postmenopausal. During the follow-up, no patient died and one patient (1%) developed non-Q wave myocardial infarction. The frequency of chest pain was unchanged or increased in 24 patients (36%) and decreased or disappeared in 42 patients (64%). The angina status was improved only in 16 of 33 patients treated with calcium channel blockers alone. By contrast, it was improved in 18 of 21 patients on the combination of calcium channel blockers and angiotensin converting enzyme inhibitors (P<0.05).

CONCLUSIONS

Patients with microvascular angina in the present study were more women and had a different risk factor profile as compared with those having epicardial spasm. Long-term prognosis was excellent with regard to mortality, but angina persisted in many patients even on calcium channel blockers. The result warrants prospective studies to evaluate the efficacy of angiotensin converting enzyme inhibitors as adjunct to calcium channel blockers in this population.

Downregulation of angiotensin II type 1 receptor by hydrophobic 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors in vascular smooth muscle cells

3-Hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase inhibitors, so-called statins, reduce the relative risk of a major coronary event by lowering the serum cholesterol level. In addition, statins may confer beneficial effects by cholesterol-lowering independent mechanisms, which are incompletely characterized. Because angiotensin II (Ang II) plays crucial roles in the pathogenesis of cardiovascular diseases, we examined the effect of statins on the expression of the Ang II type 1 receptor (AT(1)-R) in cultured vascular smooth muscle cells (VSMCs). Cerivastatin and fluvastatin reduced the AT(1)-R mRNA and the AT(1)-R protein levels; however, pravastatin lacked this effect. Cerivastatin and fluvastatin suppressed the AT(1)-R promoter activity measured by luciferase assay but did not affect AT(1)-R mRNA stability, suggesting that the suppression occurs at the transcriptional level. Coincubation of VSMCs with mevalonate or geranylgeranyl pyrophosphate but not with farnesyl pyrophosphate reversed the cerivastatin-induced AT(1)-R downregulation. Overexpression of dominant-negative Rho A also suppressed AT(1)-R mRNA expression. Treatment with cerivastatin for 24 hours reduced the calcium response of VSMCs to Ang II. Taken together, statins downregulate AT(1)-R expression through a mevalonate-dependent, geranylgeranyl pyrophosphate-dependent, and Rho A-dependent manner and attenuate the biological function of Ang II. Downregulation of AT(1)-R may contribute to the cholesterol-independent beneficial effect of statins on the cardiovascular system.

Possible involvement of Rho-kinase in the pathogenesis of hypertension in humans

Rho-kinase plays an important role in modulating Ca(2+) sensitivity of vascular smooth muscle and has been suggested to be involved in the increased systemic vascular resistance in hypertensive animals. However, it remains to be examined whether this is also the case in patients with essential hypertension. Recently, it has been shown that fasudil is a specific Rho-kinase inhibitor. The aim of this study was to examine whether Rho-kinase is involved in the pathogenesis of hypertension in humans by using this Rho-kinase inhibitor. Studies were performed in hypertensive patients (HT group, n=14) and age-matched normotensive subjects (NT group, n=12). Forearm blood flow was measured by a strain-gauge plethysmograph during intra-arterial infusion of graded doses of fasudil (3.2, 6.4, 12.8, and 25.6 microg/min) or sodium nitroprusside (0.4, 0.8, 1.6, and 3.2 microg/min). Resting forearm vascular resistance was significantly higher in the HT group than in the NT group (22+/-4 versus 17+/-5 U, respectively; P<0.05). The extent of the increase in forearm blood flow evoked by fasudil was significantly greater in the HT group than in the NT group (12.3+/-1.4 versus 6.0+/-0.6 mL. min(-1). 100 mL(-1), respectively; P<0.01). The percent decrease in forearm vascular resistance was significantly greater in the HT group than in the NT group (63.6+/-4.7% versus 29.6+/-3.9%, respectively; P<0.01). By contrast, forearm vasodilator response evoked by sodium nitroprusside was comparable between the 2 groups. These results provide the first evidence that Rho-kinase may be involved in the pathogenesis of the increased peripheral vascular resistance in hypertension in humans.

In vivo gene transfer of dominant-negative rho-kinase induces regression of coronary arteriosclerosis in pigs

Small GTPase Rho and its target Rho-kinase play an important role in various cellular functions that may be involved in the pathogenesis of arteriosclerosis. Here we show that adenovirus-mediated transfer of dominant-negative Rho-kinase (AdDNRhoK) induces a regression of coronary constrictive remodeling and abolishes coronary vasospastic activity in vivo. Porcine coronary segments were chronically treated with interleukin-1,beta which resulted in the development of constrictive remodeling and vasospastic responses to serotonin in vivo. AdDNRhoK, but not that of beta-galactosidase, into the interleukin-1beta-treated coronary segment caused regression of constrictive remodeling and abolished vasospastic activity in 3 weeks. The unregulated phosphorylation of the target proteins of Rho-kinase at the coronary lesion was significantly suppressed by AdDNRhoK. These results indicate that Rho-kinase is substantially involved in the mechanism of coronary arteriosclerosis, which can be reversed by selective inhibition of the molecule in our porcine model in vivo.

Angiomyofibroblastoma of the vulva: report of a case

A 45-year-old woman was first seen by us 2 years after becoming aware of a slightly painful subcutaneous mass in her left vulva. The mass was 7.5 x 3.0 cm in size, well circumscribed, mobile, and rubbery. It was at first clinically considered to be a benign tumor. Microscopically, the resected mass was composed of spindle or polygonal tumor cells which were cellularly or hypocellularly arranged with perivascular accentuation in a mucoid or fibrocollagenous background. Immunohistochemically, myxoid tumor cells were positive for vimentin but not for alpha-smooth muscle actin, CD34, CD31, desmin, or S-100 protein. The tumor was diagnosed as an angiomyofibroblastoma (AMBF), based on the typical findings of histology and immunohistochemistry. There are many histological types of vulvar tumors, and establishing a preoperative diagnosis is difficult in many patients. Rapid intraoperative pathological diagnosis should be performed if possible, considering the possibility of diseases such as AMFB and aggressive angiomyxoma (AAM). When AAM is suspected, the peripheral tissues should also be resected to prevent recurrence.

Thrombin induces interleukin-6 expression through the cAMP response element in vascular smooth muscle cells

The plasma level of interleukin-6 (IL-6) is elevated in patients with acute coronary syndromes and has prognostic value. Thrombin is a potent mitogen for vascular smooth muscle cells (VSMCs) and plays an important role in the progression of atherosclerosis. We examined the mechanism of thrombin-induced IL-6 expression in VSMCs. Thrombin induced IL-6 mRNA and protein expression in a dose-dependent manner. Pharmacological inhibition of extracellular signal-regulated protein kinase (ERK), p38 mitogen-activated protein kinase (MAPK), or epidermal growth factor receptor (EGF-R) suppressed the thrombin-induced IL-6 expression. Deletion and mutation analysis of the promoter region of the IL-6 gene by using luciferase as a reporter showed that the DNA segment between -228 and -150 bp containing the cAMP response element (CRE) site played a critical role. Thrombin also induced phosphorylation of CRE binding protein (CREB) in an ERK- and a p38 MAPK-dependent manner. Overexpression of the dominant-negative form of CREB inhibited thrombin-induced IL-6 mRNA expression. These results suggest that the CRE site and CREB play an important role in thrombin-induced IL-6 gene expression in VSMCs. Transactivation of EGF-R and activation of ERK and p38 MAPK are involved in this process. CREB may be a novel transcription factor that regulates thrombin-induced gene expression.

cAMP response element-binding protein mediates thrombin-induced proliferation of vascular smooth muscle cells

Thrombin is a potent mitogen for vascular smooth muscle cells (VSMCs) and plays an important role in the progression of atherosclerosis. Although recent reports have suggested that cAMP response element-binding protein (CREB) is necessary for the survival of neuronal cells, the role of CREB in VSMC proliferation is not determined. We examined the role of CREB in thrombin-induced VSMC proliferation and the effect of thrombin on phosphorylation of CREB at Ser133, which is a critical marker for activation by Western blot analysis. Thrombin induced phosphorylation of CREB in a dose-dependent manner. An oligopeptide, SFLLRN, which activates the thrombin receptor, also induced the phosphorylation of CREB. Inhibition of extracellular signal-regulated protein kinase or inhibition of p38 mitogen-activated protein kinase suppressed the thrombin-induced CREB phosphorylation. Inhibition of the epidermal growth factor receptor by AG1478 also inhibited the thrombin-induced CREB phosphorylation. Overexpression of the dominant-negative form of CREB inhibited thrombin-induced c-fos mRNA expression and incorporation of [(3)H]thymidine and [(3)H]leucine. These results suggest that CREB-dependent gene transcription plays a critical role in thrombin-induced proliferation and hypertrophy of VSMCs. Transactivation of the epidermal growth factor receptor and 2 mitogen-activated protein kinase pathways are involved in this process. CREB may be a novel transcription factor mediating the vascular remodeling process induced by thrombin.

Elevated interleukin-1beta in pericardial fluid of patients with ischemic heart disease

BACKGROUND

Inflammatory cytokines may play an important role in the pathogenesis of atherosclerosis and heart failure. We have previously demonstrated that long-term treatment with interleukin (IL)-1beta in the coronary artery and myocardium promotes coronary arteriosclerosis and impairs cardiac function, respectively. The cytokines in pericardial fluid may reflect the extent of coronary atherosclerosis and may also directly promote the atherosclerotic process. This study was designed to examine the significance of cytokine concentrations in pericardial fluid of patients with cardiovascular disease.

METHODS

We measured concentrations of 10 major cytokines in the pericardial fluid of 56 consecutive patients obtained during open heart surgery, 27 with ischemic heart disease (IHD group), 21 with valvular heart disease (VHD group) and eight with congenital heart disease (CHD group).

RESULTS

The pericardial concentrations of IL-1beta (pg/ml) were significantly higher in the IHD group (60 +/- 15) than in the VHD (29 +/- 5) or the CHD group (26 +/- 4) (P < 0.05 both). There was no significant difference in pericardial concentrations of other cytokines among the three groups. In the IHD group, the IL-1beta concentrations were significantly elevated in patients who had undergone emergency operations or in those with unstable angina.

CONCLUSIONS

These results suggest that pericardial concentrations of IL-1beta may reflect the extent of ischemic heart disease and that elevated IL-1beta concentrations in pericardial fluid may also directly promote the process of coronary atherosclerosis.

Medical and socioenvironmental predictors of hospital readmission in patients with congestive heart failure

BACKGROUND

Patients with chronic congestive heart failure (CHF) require frequent rehospitalization because of the exacerbation of CHF. It is of clinical importance to determine predicting factors for readmission to reduce this likelihood. Previous studies have focused primarily on the demographic and medical characteristics in selected subsets of patients. Therefore, within a broad cohort of consecutively hospitalized patients, we sought to identify not only demographic and medical predictors but also socioenvironmental factors associated with readmission.

METHODS

We assessed demographic (age, sex), medical (etiology of CHF, New York Heart Association functional class, left ventricular ejection fraction, previous admission for CHF, length of hospital stay, comorbidity, and medications), and socioenvironmental variables (occupation, financial resources, living alone, and follow-up visits) in 230 patients discharged with a diagnosis of CHF and recorded hospital readmission.

RESULTS

Within 1 year after discharge, 81 patients (35%) were readmitted. Five variables, including poor follow-up visits (odds ratio [OR] 4.9, 95% CI 2.0-11.8), previous admission for CHF (OR 3.3, 95% CI 1.8-6.1), no occupation (OR 2.6, 95% CI 1.2-5.5), longer hospital stay (OR 3.2, 95% CI 1.2-8.5), and hypertension (OR 2.0, 95% CI 1.1-3.7), were identified as significant independent predictors for readmission by multivariate logistic regression analysis.

CONCLUSIONS

Our independent predictors of readmission support the importance of medical and socioenvironmental factors in the deterioration of CHF. Therefore interventions to decrease readmission should also target social management in all hospitalized patients.

Overexpression of eNOS in the RVLM causes hypotension and bradycardia via GABA release

In this study, we examine the role of NO located in the rostral ventrolateral medulla (RVLM) in the control of blood pressure and the activity of the sympathetic nervous system. To determine the effect of an increase in NO production in the RVLM on blood pressure in conscious rats, adenovirus vectors encoding either endothelial NO synthase (AdeNOS) or beta-galactosidase (Adbetagal) were transfected into the bilateral RVLM. The local expression of endothelial NO synthase (eNOS) protein in the RVLM was confirmed by immunohistochemical staining for the eNOS protein and by Western blot analysis. Mean arterial blood pressure (MAP) and heart rate, which were monitored using a radio-telemetry system, were significantly decreased in the AdeNOS-treated group from day 5 to day 10 after the gene transfer. Urinary norepinephrine excretion was decreased on day 7 after the gene transfer in the AdeNOS-treated group. Microinjection of either N(G)-monomethyl-L-arginine (L-NMMA) or bicuculine, a gamma-amino butyric acid (GABA) receptor antagonist, into the RVLM at day 7 after the gene transfer increased MAP to significantly greater levels in the AdeNOS-treated group. However, microinjection of kynurenic acid into the RVLM on day 7 after the gene transfer did not alter MAP levels in either group. GABA and glutamate levels in the RVLM, when measured by in vivo microdialysis, were significantly increased in the AdeNOS-treated group. These results suggest that the increase in NO production caused by the overexpression of eNOS in the bilateral RVLM decreases blood pressure, heart rate, and sympathetic nerve activity in conscious rats. Furthermore, these responses may be mediated by an increased release of GABA in the RVLM.