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1.
Chemosphere ; 312(Pt 1): 137141, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36343734

ABSTRACT

Seaweeds are some of the principal primary producers of marine environments, and they are important ecological elements of coastal ecosystems. The effects of harmful chemicals on seaweeds may adversely affect coastal ecosystems, hence we aimed to develop a new phytotoxicity test using the gametophytes of a common temperate kelp species, Undaria pinnatifida (KU-1630), for the widely used antifouling chemical substances Cybutryne, Diuron, Cu2+, and Zn2+. Toxicity to gametophytes of U. pinnatifida was assessed by comparing the relative growth rate (RGR) at the logarithmic growth phase. Fragmentation method, initial algal biomass, photon irradiance, and adhesive period were investigated for developing optimal test conditions. Cybutryne exposure tests were performed with seven replicates and control, the RGR ranging from 0.17 to 0.19, while mean 7-day EC50 and no observed effect concentration (NOEC) were 5.1 µg/L and 1.8 µg/L, respectively. The 7-day EC50 for other antifoulants was 14 µg/L for Diuron, 17 µg/L for Cu2+, and 1500 µg/L for Zn2+. This test method demonstrated high sensitivity and reproducibility, and it may be added to the routine methods used for toxicity evaluation of hazardous chemicals.


Subject(s)
Biofouling , Seaweed , Undaria , Diuron/toxicity , Ecosystem , Reproducibility of Results , Biofouling/prevention & control
2.
Phys Rev E ; 106(2-2): 025205, 2022 Aug.
Article in English | MEDLINE | ID: mdl-36109929

ABSTRACT

A developing supercritical collisionless shock propagating in a homogeneously magnetized plasma of ambient gas origin having higher uniformity than the previous experiments is formed by using high-power laser experiment. The ambient plasma is not contaminated by the plasma produced in the early time after the laser shot. While the observed developing shock does not have stationary downstream structure, it possesses some characteristics of a magnetized supercritical shock, which are supported by a one-dimensional full particle-in-cell simulation taking the effect of finite time of laser-target interaction into account.

3.
Phys Rev E ; 105(2-2): 025203, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35291161

ABSTRACT

We present an experimental method to generate quasiperpendicular supercritical magnetized collisionless shocks. In our experiment, ambient nitrogen (N) plasma is at rest and well magnetized, and it has uniform mass density. The plasma is pushed by laser-driven ablation aluminum (Al) plasma. Streaked optical pyrometry and spatially resolved laser collective Thomson scattering clarify structures of plasma density and temperatures, which are compared with one-dimensional particle-in-cell simulations. It is indicated that just after the laser irradiation, the Al plasma is magnetized by a self-generated Biermann battery field, and the plasma slaps the incident N plasma. The compressed external field in the N plasma reflects N ions, leading to counterstreaming magnetized N flows. Namely, we identify the edge of the reflected N ions. Such interacting plasmas form a magnetized collisionless shock.

4.
BMC Palliat Care ; 19(1): 12, 2020 Jan 24.
Article in English | MEDLINE | ID: mdl-31980015

ABSTRACT

BACKGROUND: Palliative care (PC) is increasingly recognized as essential for oncology care, and several academic societies strongly recommend integrating oncology and palliative care (IOP) in daily practice. Similarly, the Japanese government encouraged the implementation of IOP through the Cancer Control Act of 2007; however, its detailed progress remains unclear. Therefore, this cross-sectional nationwide survey was conducted to investigate the current status and hospital executive physicians' perception of IOP. METHODS: The questionnaire was developed based on IOP indicators with international consensus. It was distributed to executive physicians at all government-designated cancer hospitals (DCHs, n = 399) and matched non-DCHs (n = 478) in November 2017 and the results were compared. RESULTS: In total, 269 (67.4%) DCHs and 259 (54.2%) non-DCHs responded. The number of PC resources in DCHs was significantly higher than those in non-DCHs (e.g., full-time PC physicians and nurses, 52.8% vs. 14.0%, p < 0.001; availability of outpatient PC service ≥3 days per week, 47.6% vs. 20.7%, p < 0.001). Routine symptom screening was more frequently performed in DCHs than in non-DCHs (65.1% vs. 34.7%, p < 0.001). Automatic trigger for PC referral availability was limited (e.g., referral using time trigger, 14.9% vs. 15.3%, p = 0.700). Education and research opportunities were seriously limited in both types of hospitals. Most executive physicians regarded IOP as beneficial for their patients (95.9% vs. 94.7%, p = 0.163) and were willing to facilitate an early referral to PC services (54.7% vs. 60.0%, p < 0.569); however, the majority faced challenges to increase the number of full-time PC staff, and < 30% were planning to increase the staff members. CONCLUSIONS: This survey highlighted a considerable number of IOP indicators met, particularly in DCHs probably due to the government policy. Further efforts are needed to address the serious research/educational gaps.


Subject(s)
Delivery of Health Care, Integrated/trends , Oncology Service, Hospital/trends , Palliative Care/methods , Cross-Sectional Studies , Delivery of Health Care, Integrated/methods , Delivery of Health Care, Integrated/standards , Humans , Japan , Oncology Service, Hospital/standards , Palliative Care/standards , Palliative Care/trends , Surveys and Questionnaires
5.
Clin Exp Immunol ; 195(1): 109-120, 2019 01.
Article in English | MEDLINE | ID: mdl-30194773

ABSTRACT

To investigate possible roles of T helper type 2 (Th2) cytokines in the anti-arthritic effects of a blood fluke, Schistosoma mansoni (Sm), for mouse collagen-induced arthritis (CIA), wild-type (WT), signal transducer and activator of transcription 6 (STAT6) knock-out (KO) and interleukin (IL)-10 KO mice were infected with Sm. Three weeks after infection, the mice were immunized with bovine type II collagen (IIC). Arthritis severity was monitored by scoring, measurement of paw thickness and the presence of ankylosis. Serum anti-IIC IgG levels, splenic cytokine production and cytokine gene expression in the popliteal lymph nodes (PLNs) were measured and compared among WT and gene-KO mice. Consistent with our previous findings, Sm infection reduced the arthritis severity in WT mice. Splenic production of IL-17A and tumor necrosis factor (TNF)-α was reduced by the infection. In contrast, Sm infection markedly exacerbated CIA in STAT6 KO mice. In the KO mice, IL-17A production was increased by the infection. Conversely, Sm infection did not affect the exacerbated arthritis in IL-10 KO mice, although IL-17A production was reduced by the helminth. Our results suggest that signaling via STAT6 (presumably IL-4 and/or IL-13) and IL-10 is required for the suppression of CIA by Sm infection, but through different mechanisms. STAT6 was essential for helminth-induced reduction of IL-17A, whereas regulation of the basal arthritis severity by IL-10 was needed in order for it to be sufficiently suppressed by the helminth.


Subject(s)
Arthritis, Experimental/immunology , Arthritis, Rheumatoid/immunology , Interleukin-10/metabolism , STAT6 Transcription Factor/metabolism , Schistosoma mansoni/physiology , Schistosomiasis mansoni/immunology , Animals , Ankylosis , Autoantibodies/blood , Coinfection , Collagen Type II/immunology , Edema , Humans , Interleukin-10/genetics , Interleukin-17/blood , Male , Mice , Mice, Inbred DBA , Mice, Knockout , STAT6 Transcription Factor/genetics , Signal Transduction , Tumor Necrosis Factor-alpha/blood
6.
Persoonia ; 41: 142-174, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30728603

ABSTRACT

Although Aspergillus fumigatus is the major agent of invasive aspergillosis, an increasing number of infections are caused by its cryptic species, especially A. lentulus and the A. viridinutans species complex (AVSC). Their identification is clinically relevant because of antifungal drug resistance and refractory infections. Species boundaries in the AVSC are unresolved since most species have uniform morphology and produce interspecific hybrids in vitro. Clinical and environmental strains from six continents (n = 110) were characterized by DNA sequencing of four to six loci. Biological compatibilities were tested within and between major phylogenetic clades, and ascospore morphology was characterised. Species delimitation methods based on the multispecies coalescent model (MSC) supported recognition of ten species including one new species. Four species are confirmed opportunistic pathogens; A. udagawae followed by A. felis and A. pseudoviridinutans are known from opportunistic human infections, while A. felis followed by A. udagawae and A. wyomingensis are agents of feline sino-orbital aspergillosis. Recently described human-pathogenic species A. parafelis and A. pseudofelis are synonymized with A. felis and an epitype is designated for A. udagawae. Intraspecific mating assay showed that only a few of the heterothallic species can readily generate sexual morphs in vitro. Interspecific mating assays revealed that five different species combinations were biologically compatible. Hybrid ascospores had atypical surface ornamentation and significantly different dimensions compared to parental species. This suggests that species limits in the AVSC are maintained by both pre- and post-zygotic barriers and these species display a great potential for rapid adaptation and modulation of virulence. This study highlights that a sufficient number of strains representing genetic diversity within a species is essential for meaningful species boundaries delimitation in cryptic species complexes. MSC-based delimitation methods are robust and suitable tools for evaluation of boundaries between these species.

8.
Diabetes Obes Metab ; 15(4): 364-71, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23163910

ABSTRACT

AIMS: In a phase III study conducted among Japanese patients with type 2 diabetes mellitus (T2DM), linagliptin 5 and 10 mg showed clinically meaningful improvements in glycaemic parameters after 12 and 26 weeks compared with placebo and voglibose, respectively. This extension study assessed long-term tolerability of linagliptin over 52 weeks. METHODS: Japanese patients with T2DM who completed either phase of a 12-week/26-week study comparing linagliptin monotherapy with placebo or voglibose were eligible to enrol. In the extension study, the comparator groups switched to linagliptin 5 or 10 mg, while the linagliptin groups maintained dosage. RESULTS: In all, 540 patients received at least one dose of linagliptin 5 or 10 mg and 494 completed the extension. Long-term treatment with linagliptin was well tolerated; adverse events (AEs) of special interest and serious AEs occurred in small percentages of patients. Drug-related AEs occurred in 10.2 and 10.6% of patients in the linagliptin 5- and 10-mg groups, respectively, and discontinuations due to drug-related AEs occurred in 1.1 and 0.7%, respectively. Only one (0.4%) patient in each dose group experienced investigator-defined hypoglycaemia during the treatment period (both events were non-severe). Body weight was not clinically altered in either group. The glycated haemoglobin A1c profiles over time were similar with linagliptin 5 and 10 mg. CONCLUSIONS: These findings provide evidence for the safety and tolerability of oral linagliptin at either 5 or 10 mg for up to 52 weeks for the treatment of Japanese patients with T2DM, without clinically relevant increase in the risk of hypoglycaemia or weight gain.


Subject(s)
Asian People , Diabetes Mellitus, Type 2/drug therapy , Hypoglycemic Agents/therapeutic use , Inositol/analogs & derivatives , Purines/therapeutic use , Quinazolines/therapeutic use , Adult , Aged , Aged, 80 and over , Blood Glucose/drug effects , Blood Glucose/metabolism , Body Mass Index , Body Weight , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/ethnology , Dose-Response Relationship, Drug , Double-Blind Method , Drug Administration Schedule , Female , Glycated Hemoglobin/drug effects , Glycated Hemoglobin/metabolism , Humans , Inositol/therapeutic use , Linagliptin , Male , Middle Aged , Time Factors
9.
Acta Diabetol ; 49 Suppl 1: S15-24, 2012 Dec.
Article in English | MEDLINE | ID: mdl-18008027

ABSTRACT

The purpose of the present study was to investigate the renoprotective effect of telmisartan, an angiotensin II receptor antagonist, on the early stages of diabetic nephropathy in obese Zucker rats, which is a type 2-related diabetes mellitus model. Telmisartan 1, 3 or 10 mg/kg/day was orally administered to 7-week-old rats that demonstrated glucose tolerance without albuminuria or proteinuria, for 24 consecutive weeks (Experiment A). In another experiment (Experiment B), oral administration of telmisartan 10 mg/kg/day was initiated at the age of 16 weeks after the rats demonstrated marked proteinuria, and continued for 24 weeks. Telmisartan inhibited the increase in proteinuria and albuminuria in a dose-dependent manner, and the inhibition for all telmisartan groups was statistically significant by the completion of administration (Experiment A). Telmisartan also displayed similar inhibitory effects on proteinuria and albuminuria in Experiment B. Histologically, telmisartan [3 and 10 mg/kg/day] was associated with a significant decrease in the progression of glomerulosclerosis, and significantly improved interstitial cell infiltration, interstitial fibrosis and dilation and atrophy of renal tubules. Furthermore, telmisartan treatment was associated with a tendency towards normalized plasma lipids (total cholesterol and triglyceride). Our results suggest that telmisartan has a definite renoprotective effect against renal injury in type II diabetic nephropathy.


Subject(s)
Angiotensin II Type 1 Receptor Blockers/administration & dosage , Benzimidazoles/administration & dosage , Benzoates/administration & dosage , Diabetes Mellitus, Type 2/complications , Diabetic Nephropathies/drug therapy , Diabetic Nephropathies/prevention & control , Albuminuria/drug therapy , Animals , Cholesterol/metabolism , Diabetic Nephropathies/metabolism , Humans , Kidney/drug effects , Male , Proteinuria/drug therapy , Rats , Rats, Zucker , Telmisartan , Triglycerides/metabolism , Urine/chemistry
10.
Diabetes Obes Metab ; 14(4): 348-57, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22145698

ABSTRACT

AIMS: To evaluate the efficacy and safety of linagliptin 5 and 10 mg vs. placebo and voglibose in Japanese patients with type 2 diabetes mellitus (T2DM). METHODS: This study enrolled patients with inadequately controlled T2DM who were previously treated with one or two oral antidiabetics or were drug naÏve. After a 2 to 4-week washout and placebo run-in, 561 patients were randomized (2 : 2 : 2 : 1) to double-blind treatment with linagliptin 5 or 10 mg qd, voglibose 0.2 mg tid or placebo. The primary endpoint was the change from baseline in haemoglobin A1c (HbA1c) with linagliptin vs. placebo after 12 weeks and vs. voglibose after 26 weeks. RESULTS: Baseline characteristics were well balanced across treatment groups (overall mean HbA1c was 8.01%). The adjusted mean (95% confidence interval) treatment differences at week 12 were -0.87% (-1.04, -0.70; p < 0.0001) and -0.88% (-1.05, -0.71; p < 0.0001) for linagliptin 5 and 10 mg vs. placebo and at week 26 were -0.32% (-0.49, -0.15; p = 0.0003) and -0.39% (-0.56, -0.21; p < 0.0001) for linagliptin 5 and 10 mg vs. voglibose. At week 12, mean HbA1c was 7.58, 7.48 and 8.34% in patients receiving linagliptin 5 mg, linagliptin 10 mg and placebo, respectively. At week 26, mean HbA1c was 7.63% with linagliptin 5 mg, 7.50% with linagliptin 10 mg and 7.91% with voglibose. Drug-related adverse event rates were comparable across treatment groups over 12 weeks (9.4% linagliptin 5 mg, 8.8% linagliptin 10 mg and 10.0% placebo) and 26 weeks (11.3% linagliptin 5 mg, 10.6% linagliptin 10 mg and 18.5% voglibose). There were no documented cases of hypoglycaemia. CONCLUSIONS: Linagliptin showed superior glucose-lowering efficacy and comparable safety and tolerability to both placebo and voglibose in Japanese patients with T2DM.


Subject(s)
Blood Glucose/drug effects , Diabetes Mellitus, Type 2/drug therapy , Dipeptidyl-Peptidase IV Inhibitors/therapeutic use , Inositol/analogs & derivatives , Purines/therapeutic use , Quinazolines/therapeutic use , Adult , Aged , Aged, 80 and over , Analysis of Variance , Diabetes Mellitus, Type 2/epidemiology , Dipeptidyl-Peptidase IV Inhibitors/administration & dosage , Dipeptidyl-Peptidase IV Inhibitors/adverse effects , Dose-Response Relationship, Drug , Double-Blind Method , Drug Administration Schedule , Female , Humans , Hypoglycemic Agents/therapeutic use , Inositol/therapeutic use , Japan , Linagliptin , Male , Middle Aged , Purines/administration & dosage , Purines/adverse effects , Quinazolines/administration & dosage , Quinazolines/adverse effects , Treatment Outcome
11.
Diabetes Obes Metab ; 11(8): 813-8, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19476471

ABSTRACT

AIMS: To develop predictive formulas using short-term changes in glycaemic parameters [haemoglobin A1c (HbA1c) and fasting plasma glucose (FPG)] with sitagliptin, a highly selective dipeptidyl peptidase-4 inhibitor, to assess longer term steady-state changes in HbA1c. METHODS: Results from two, 12-week, double-blind studies of sitagliptin in Japanese patients with type 2 diabetes mellitus receiving once-daily sitagliptin 100 mg were used to construct linear models to develop predictive formulas based on study 1 (S1) and to validate them using study 2 (S2). HbA1c and FPG were the primary and the key secondary end-point for both studies and were both used to develop predictive formulas. RESULTS: The predictive formulas using HbA1c+/-FPG results (slope of change) from week 0 to week 4 in S1 showed high correlations between fitted and observed week 12 HbA1c: for HbA1c alone R2=0.76, for HbA1c+FPG R2=0.89. When using the sitagliptin 100 mg group of S2 data set to assess the validity of the predictive formulas, high correlations for HbA1c alone (R2=0.76) and for HbA1c+FPG (R2=0.77) were also observed. Data using a lower dose (25 mg once daily) of sitagliptin also demonstrated similar results. CONCLUSIONS: The early responses (over 4 weeks) in HbA1c and FPG with sitagliptin can be used to accurately predict later responses (at week 12) in HbA1c in Japanese patients with type 2 diabetes mellitus. Additional studies applying this approach to other agents with diverse mechanisms are important.


Subject(s)
Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/drug therapy , Dipeptidyl-Peptidase IV Inhibitors/therapeutic use , Glycated Hemoglobin/metabolism , Pyrazines/therapeutic use , Triazoles/therapeutic use , Adult , Aged , Blood Glucose/analysis , Double-Blind Method , Fasting , Female , Humans , Linear Models , Male , Middle Aged , Sitagliptin Phosphate
14.
Gut ; 55(3): 415-24, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16174657

ABSTRACT

BACKGROUND: While tumour necrosis factor alpha (TNF-alpha) appears to be associated with the development of non-alcoholic steatohepatitis (NASH), its precise role in the pathogenesis of NASH is not well understood. METHODS: Male mice deficient in both TNF receptors 1 (TNFR1) and 2 (TNFR2) (TNFRDKO mice) and wild-type mice were fed a methionine and choline deficient (MCD) diet or a control diet for eight weeks, maintaining isoenergetic intake. RESULTS: MCD dietary feeding of TNFRDKO mice for eight weeks resulted in attenuated liver steatosis and fibrosis compared with control wild-type mice. In the liver, the number of activated hepatic Kupffer cells recruited was significantly decreased in TNFRDKO mice after MCD dietary feeding. In addition, hepatic induction of TNF-alpha, vascular cell adhesion molecule 1, and intracellular adhesion molecule 1 was significantly suppressed in TNFRDKO mice. While in control animals MCD dietary feeding dramatically increased mRNA expression of tissue inhibitor of metalloproteinase 1 (TIMP-1) in both whole liver and hepatic stellate cells, concomitant with enhanced activation of hepatic stellate cells, both factors were significantly lower in TNFRDKO mice. In primary cultures, TNF-alpha administration enhanced TIMP-1 mRNA expression in activated hepatic stellate cells and suppressed apoptotic induction in activated hepatic stellate cells. Inhibition of TNF induced TIMP-1 upregulation by TIMP-1 specific siRNA reversed the apoptotic suppression seen in hepatic stellate cells. CONCLUSIONS: Enhancement of the TNF-alpha/TNFR mediated signalling pathway via activation of Kupffer cells in an autocrine or paracrine manner may be critically involved in the pathogenesis of liver fibrosis in this NASH animal model.


Subject(s)
Fatty Liver/complications , Kupffer Cells/metabolism , Liver Cirrhosis, Experimental/etiology , Tumor Necrosis Factor-alpha/physiology , Animals , Apoptosis , Cell Adhesion Molecules/biosynthesis , Choline Deficiency/complications , Fatty Liver/metabolism , Fatty Liver/pathology , Gene Expression Regulation , Liver Cirrhosis, Experimental/metabolism , Liver Cirrhosis, Experimental/pathology , Male , Methionine/deficiency , Mice , Mice, Knockout , Mitochondria, Liver/physiology , Mutation , RNA, Messenger/genetics , Receptors, Tumor Necrosis Factor, Type I/deficiency , Receptors, Tumor Necrosis Factor, Type I/genetics , Receptors, Tumor Necrosis Factor, Type I/physiology , Receptors, Tumor Necrosis Factor, Type II/deficiency , Receptors, Tumor Necrosis Factor, Type II/genetics , Receptors, Tumor Necrosis Factor, Type II/physiology , Reverse Transcriptase Polymerase Chain Reaction/methods , Signal Transduction , Tissue Inhibitor of Metalloproteinase-1/biosynthesis , Tissue Inhibitor of Metalloproteinase-1/genetics , Tumor Necrosis Factor-alpha/biosynthesis
15.
Aliment Pharmacol Ther ; 20 Suppl 1: 151-7, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15298621

ABSTRACT

BACKGROUND AND AIMS: Tube feeding is regarded as a risk factor for Clostridium difficile-associated diarrhoea. Recently, we reported that C. difficile toxin was frequently found in patients receiving an elemental diet. The present study was conducted to clarify whether elemental diets are associated with the growth of C. difficile in the gut flora. METHODS: C. difficile was cultured for 72 h in various concentrations of elemental diet containing 3% thioglycollate, and the growth rate or activity of C. difficile was evaluated by Gram stain or by measuring optical density at 560 nm. Faecal samples from 10 healthy adults were cultured in elemental diet + 3% thioglycollate. RNA was extracted from faeces with glass powder, which can eliminate PCR inhibitors, and mRNA of C. difficile toxin B was measured by reverse transcription PCR. RESULTS: Maximum OD560 value during culture in thioglycollate-containing elemental diet was 2.4 times higher than that in thioglycollate alone (P = 0.0163). Viability of C. difficile was decreased in thioglycollate but not in thioglycollate-containing elemental diet. Toxin B mRNA was detected in five faecal samples (50%) before culture and in all samples after culture. CONCLUSIONS: Our results suggest that an elemental diet can modulate the growth of C. difficile in the gut flora.


Subject(s)
Clostridioides difficile/growth & development , Food, Formulated , Adult , Aged , Bacterial Toxins/isolation & purification , Cell Division , Clostridioides difficile/isolation & purification , Feces/microbiology , Female , Humans , Intestines/microbiology , Male , Middle Aged
16.
J Dent Res ; 82(2): 96-100, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12562880

ABSTRACT

Class II major histocompatilibity complex (MHC)-expressing cells are usually distributed in dental pulp, and it was postulated that the colony-stimulating factor (CSF) derived from dental pulp fibroblasts contributes to the migration of class II MHC-expressing cells into pulp tissue. This study aimed to investigate the CSF production of human dental pulp fibroblasts. In pulp tissue sections, granulocyte (G)-CSF was detected from normal teeth, while G-CSF, macrophage (M)-CSF, and granulocyte-macrophage (GM)-CSF were detected from teeth with dentinal caries. In cultured dental pulp fibroblasts, G-CSF was detected by immunostaining, immunoprecipitation, and ELISA, and mRNAs of G-CSF, M-CSF, and GM-CSF were detected by RT-PCR. The dental pulp fibroblasts cultured with TNF-alpha were found to increase the G-CSF expression and to produce M-CSF and GM-CSF. These findings suggest that dental pulp fibroblasts usually produce G-CSF. In the presence of TNF-alpha, dental pulp fibroblast express M-CSF and GM-CSF.


Subject(s)
Colony-Stimulating Factors/biosynthesis , Dental Pulp/metabolism , Adolescent , Adult , Cells, Cultured , Dental Pulp/cytology , Dental Pulp/drug effects , Enzyme-Linked Immunosorbent Assay , Fibroblasts/drug effects , Fibroblasts/metabolism , Granulocyte Colony-Stimulating Factor/biosynthesis , Granulocyte-Macrophage Colony-Stimulating Factor/biosynthesis , Histocompatibility Antigens Class II/biosynthesis , Humans , Immunoblotting , Macrophage Colony-Stimulating Factor/biosynthesis , Precipitin Tests , Reverse Transcriptase Polymerase Chain Reaction , Tumor Necrosis Factor-alpha/pharmacology
17.
Nihon Arukoru Yakubutsu Igakkai Zasshi ; 36(5): 471-85, 2001 Oct.
Article in Japanese | MEDLINE | ID: mdl-11725532

ABSTRACT

Although alcohol is well recognized as a systemic toxin, the enteric manifestations of alcohol abuse have only recently begun to be elucidated at the cellular and microvascular levels. Since the microvascular mechanism of the toxicity of alcohol has progressively been revealed, clinical applications of this research field should increase the availability of therapeutic options for alcohol-induced injuries of liver, pancreas and gastrointestinal (GI) tract. A high concentration of ethanol reduces GI and pancreas blood flow. Ethanol-induced GI hemorrhage, GI ulcer, and pancreatitis are initiated by the microcirculatory disturbance of GI mucosa and pancreas. Ethanol administration induces an increase in vasoactive agents such as endothelin and nitric oxide and oxidative stress. They appear to be involved in ethanol-induced GI and pancreatic injury. Regarding the effects of ethanol on the liver, small amount of ethanol increases hepatic blood flow, and prevents gut ischemia/reperfusion (I/R)-induced hepatic microvascular dysfunction and subsequent liver injury. While large amount of ethanol itself causes hepatic microvascular dysfunction, and aggravates the gut I/R-induced hepatic microvascular dysfunction and subsequent liver injury. Vasoactive agents and oxidative stress also appear to be involved in the liver injury. In endotoxemic animals, even small amount of ethanol causes hepatic microvascular dysfunction. Chronic ethanol consumption aggravates endotoxin-induced hepatic microvascular dysfunction. Chronic ethanol consumption aggravates gut I/R-induced leukostasis in the liver and hepatocellular injury associated with an enhanced expression of adhesion molecules, while it prevents the gut I/R-induced sinusoidal perfusion injury. Thus, effects of chronic ethanol consumption on the I/R injury are still controversial.


Subject(s)
Ethanol/adverse effects , Gastric Mucosa/blood supply , Gastrointestinal Diseases/etiology , Hepatitis, Alcoholic/etiology , Liver/blood supply , Pancreas/blood supply , Pancreatitis, Alcoholic/etiology , Animals , Cell Adhesion Molecules/physiology , Endothelins/physiology , Humans , Leukocytes/pathology , Microcirculation/drug effects , Nitric Oxide/physiology , Oxidative Stress
18.
J Gastroenterol Hepatol ; 16(8): 916-22, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11555107

ABSTRACT

BACKGROUND: We examined the role of endothelin in endotoxin-induced hepatic microcirculatory disturbance in pair-fed rats given a liquid diet containing ethanol or isocaloric control. METHODS AND RESULTS: One lobe of the liver was observed with the use of an intravital microscope. Erythrocytes (RBCs) labeled with fluorescein isothiocyanate (FITC) were injected, and the flow velocity of the FITC-RBCs in the sinusoids was measured with an off-line velocimeter. The flow velocity decreased 30 min after 1 mg/kg of lipopolysaccharide (LPS) was administered to the controls, and portal pressure (PP) was increased at 60 min. In ethanol-fed rats, however, both the flow velocity and PP increased in the early phase (at 10 min), and in the late phase, flow velocity decreased and PP increased more than in the controls. The LPS-induced decrease in flow velocity was blunted, when BQ-123, an antagonist of endothelin receptor subtype A, was infused into ethanol-fed rats, and BQ-123 also attenuated the change in PP. The plasma endothelin levels in both systemic and portal blood of the ethanol-fed rats were higher than in the controls. CONCLUSIONS: These results suggest that endothelin plays a role in the LPS-induced hepatic microcirculatory disturbance, especially in alcohol-fed animals.


Subject(s)
Endothelins/adverse effects , Erythrocytes/drug effects , Liver Diseases/etiology , Liver/blood supply , Alanine Transaminase/blood , Animals , Aspartate Aminotransferases/blood , Blood Flow Velocity/drug effects , Blood Pressure/drug effects , Blood Pressure/physiology , Disease Models, Animal , Endothelins/blood , Erythrocytes/physiology , Ethanol , Lipopolysaccharides/adverse effects , Liver Diseases/physiopathology , Male , Microcirculation , Portal Pressure/drug effects , Rats , Rats, Wistar
19.
Jpn Circ J ; 65(8): 723-30, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11502049

ABSTRACT

The present study investigated the incidence and ECG characteristics of ventricular tachycardias (VTs) originating from the left ventricular (LV) epicardium. Thirty-one consecutive patients with VT or premature ventricular contraction originating from the outflow tract (OT-VT) underwent catheter ablation. Twenty-one OT-VTs were ablated from the endocardium in the right ventricular (RV) OT and 3 were ablated from the endocardium in the LVOT. In the remaining 7 patients, 4 (13%) OT-VTs were LV epicardial in origin, and 1 of these was ablated from the left sinus of Valsalva. The ECG characteristics of OT-VT of epicardial origin included prominent tall R-waves in the inferior leads, an R-wave in V1 and an S-wave in V2, precordial R-wave transition in V2-4, a deep QS-wave in aVL, and no S-wave in V6. In addition, there was an atypical left bundle branch block morphology with an inferior axis. These findings were observed during pacing from several sites in the LV epicardium. Furthermore, pacing from the left sinus of Valsalva caused a relatively tall R in V1, deep S-wave in V2 and a tall R-wave with a shallow S-wave in V3, as well as tall R-waves in the inferior leads, which represented intermediate characteristics between RV endocardial OT-VT and LV endocardial OT-VT. In conclusion, OT-VT originating from the LV epicardium is not uncommon and has characteristic ECG findings. Some of them can be ablated from the left sinus of Valsalva.


Subject(s)
Electrocardiography , Tachycardia, Ventricular/physiopathology , Adult , Aged , Catheter Ablation , Electrophysiologic Techniques, Cardiac , Electrophysiology , Female , Humans , Male , Middle Aged , Pericardium , Tachycardia, Ventricular/surgery , Ventricular Function, Left
20.
Pathophysiology ; 8(1): 11-20, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11476968

ABSTRACT

Gut ischemia and reperfusion (I/R) has been implicated as a prime mechanism in the pathogenesis of multiple organ failure and in initiating remote organ failure. Although it has long been known that gut I/R elicits liver dysfunction, only recently has the kinetics of leukocyte accumulation in the hepatic microcirculation and mechanisms of the liver injury after gut I/R been investigated. These studies reveal that the magnitude of gut I/R-induced liver injury depends on the duration of ischemic period and animal species. Gut I/R-induced accumulation of leukocytes, both neutrophils and lymphocytes, in the liver results in an oxidative stress in proximity to non-perfused sinusoid that contributes to subsequent hepatocellular injury. The gut I/R-induced leukosequestration in the liver is mediated by adhesion molecules that are induced by different cytokines, endotoxin, and oxidants. Kupffer cells also play an important role in the gut I/R-induced leukosequestration and liver injury. Nitric oxide and anti-oxidants such as superoxide dismutase protect the liver against the deleterious effects of gut I/R. Furthermore, agents such as ethanol can alter the hepatic responses to gut I/R. The results of these studies provide novel information and potential therapeutic strategies for reducing the liver dysfunction and multiple organ failure induced by gut I/R.

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