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One of the most common causes of discontinued peritoneal dialysis is impaired peritoneal function. However, its molecular mechanisms remain unclear. Previously, by microarray analysis of mouse peritoneum, we showed that MMP (matrix metalloproteinase)-10 expression is significantly increased in mice with peritoneal fibrosis, but its function remains unknown. Chlorhexidine gluconate (CG) was intraperitoneally injected to wild-type and MMP-10 knockout mice to induce fibrosis to elucidate the role of MMP-10 on peritoneal injury. We also examined function of peritoneal macrophages and mesothelial cells obtained from wild-type and MMP-10 knockout mice, MMP-10-overexpressing macrophage-like RAW 264.7 cells and MeT-5A mesothelial cells, investigated MMP-10 expression on peritoneal biopsy specimens, and the association between serum proMMP-10 and peritoneal solute transfer rates determined by peritoneal equilibration test on patients. MMP-10 was expressed in cells positive for WT1, a mesothelial marker, and for MAC-2, a macrophage marker, in the thickened peritoneum of both mice and patients. Serum proMMP-10 levels were well correlated with peritoneal solute transfer rates. Peritoneal fibrosis, inflammation, and high peritoneal solute transfer rates induced by CG were all ameliorated by MMP-10 deletion, with reduction of CD31-positive vessels and VEGF-A-positive cells. Expression of inflammatory mediators and phosphorylation of NFκΒ subunit p65 at S536 were suppressed in both MMP-10 knockout macrophages and mesothelial cells in response to lipopolysaccharide stimulation. Overexpression of MMP-10 in RAW 264.7 and MeT-5A cells upregulated pro-inflammatory cytokines with phosphorylation of NFκΒ subunit p65. Thus, our results suggest that inflammatory responses induced by MMP-10 are mediated through the NFκΒ pathway, and that systemic deletion of MMP-10 ameliorates peritoneal inflammation and fibrosis caused by NFκΒ activation of peritoneal macrophages and mesothelial cells., (Copyright © 2023 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.)

We synthesized N-acetylglucosamine-terminated hexavalent carbosilane dendrimers and investigated their binding to wheat germ agglutinin (WGA). The glycodendrimers were prepared by the conjugation of 3-mercaptopropyl, 4-mercaptobutyl, or 5‑mercaptopentyl glycosides to maleimide-terminated hexavalent carbosilane dendrimers. Titration of WGA with the glycodendrimers yielded quenching of tryptophan fluorescence. All of the glycodendrimers exhibited high affinity with nanomolar dissociation constants (K D values). The best dendrimers were 1a and 1b with K D values of 6.5 ± 1.7 and 5.3 ± 1.7 nM, respectively. The magnitude of fluorescence quenching increased with decrease in the length of the thioalkyl spacer. Maleimide-pendant carbosilane dendrimers provide ready access to multivalent ligands with high-affinity potential., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Introduction/objectives: The American College of Veterinary Internal Medicine (ACVIM) guidelines suggest that pimobendan should be initiated in dogs which meet all criteria of stage B2 myxomatous mitral valve disease (MMVD): murmur intensity ≥ 3/6, left atrial-to-aortic ratio ≥ 1.6, normalized left ventricular internal diameter in diastole ≥ 1.7, and vertebral heart size > 10.5. Recently, a new radiographic index for left atrial enlargement, vertebral left atrial size (VLAS), was proposed. The objective of the present study was to evaluate whether VLAS is useful in staging MMVD and if it can distinguish between ACVIM stages B1 and B2., Animals: Ninety-seven client-owned dogs with MMVD were evaluated and classified as ACVIM stage B1, B2, or C-D., Materials and Methods: The echocardiographs and radiographs of all the dogs were retrospectively evaluated to obtain left atrial-to-aortic ratio, normalized left ventricular internal diameter in diastole, and VLAS values. The data were analyzed to assess the correlation between these measurements and VLAS, and the optimal cutoff value of VLAS was determined., Results: A VLAS cutoff value of 2.6 provided the greatest diagnostic accuracy for identification of dogs with ACVIM stage B2 MMVD (area under the curve, 0.96; sensitivity, 95%; specificity, 84%). A VLAS ≥2.5 exhibited the highest sensitivity (sensitivity, 100%; specificity, 78%), and a VLAS ≥ 3.1 exhibited the highest specificity (sensitivity, 47%; specificity, 100%)., Conclusions: VLAS is a helpful index for monitoring MMVD using radiography. A VLAS cutoff value of 2.5 could be used to identify dogs that may benefit from echocardiography to determine if they have reached ACVIM stage B2., Competing Interests: Conflict of Interest Statement The authors do not have any conflicts of interest to disclose., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Toxoplasma gondii can infect almost all mammals and birds, including chickens. The aim of this study was to identify an appropriate immunogenic antigen for serodiagnosis of T. gondii infections in chickens. We examined serum samples from chickens that were intravenously or intraperitoneally infected with 10 6 -10 8 tachyzoites of T. gondii strains PLK, RH, CTG, ME49 or TgCatJpGi1/TaJ using enzyme-linked immunosorbent assays (ELISAs), latex agglutination tests (LATs) and western blotting. Regardless of parasite strain or infection dose and route, the commercial LAT was positive for almost all sera collected 1 week post-infection. However, at 2 weeks post-infection, LATs were negative in the same birds. ELISAs using the Escherichia coli-produced recombinant T. gondii antigens SAG1 and GRA7 showed strong signals at 1-2 weeks post infection, but thereafter diminished for the majority of serum samples. In contrast, western blotting against crude tachyzoite antigens showed a persistent band up to 4 weeks post-infection. Sera from these chickens reacted much more strongly with SAG1 from crude tachyzoite antigens than with recombinant SAG1. Even in experimentally-infected birds whose parasite burdens in tissue were undetectable, sera still reacted with native SAG1. We tested sera from free-range chickens on a small farm in Ghana, Africa, using western blotting and found that the serum of one bird reacted with a single band of approximately 27 kDa, the putative molecular weight of SAG1. Thus we conclude that native SAG1, but not E. coli-produced recombinant SAG1, is suitable for serodiagnosis of T. gondii infections in chickens., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Lipopolysaccharides (LPS) are components of the Gram-negative bacterial cell surface that stimulate the host innate immune system through the Toll-like receptor (TLR) 4-MD-2 complex. Rhodobacter sp. have been reported to produce LPS that lack endotoxic activity, and instead act as antagonists of other endotoxins. In this report, we focused on LPS, especially the lipooligosaccharide (LOS) fraction produced by Rhodobacter azotoformans that shows production of IL-8, but has an inverse correlation with IL-6 production. We analyzed their molecular structure by using mass spectrometry and nuclear magnetic resonance spectroscopy and report a novel LOS consisting of a shorter glycan structure containing glucuronic acid but not heptoses. A novel glycan structure, Glcα(1 → 4)GlcAα(1 → 4)KDOα(2 → 4)[Glcα(1 → 5)]KDOα(2 → 6)[4-phosphate]GlcNβ(1 → 6) GlcNα1-phosphate, was proposed using NMR methods. The structure was consistent with one obtained based on MS. The MS analysis further revealed the existence of structural variation caused by extension with hexoses. The acyl composition in lipid A was suggested to contain three C14 fatty acyl chains (3-OH-14:0 or 3-oxo-14:0 at N2 of GlcN-1, 3-OH-14:0 at N2 of GlcN-2, that carried another 14:1 Δ7 on its β-hydroxyl group) and two C10 fatty acyl chains (3-OH-10:0 at O3 of both GlcN), which are same as those found in lipid A from Rhodobacter sphaeroides., (Copyright © 2018. Published by Elsevier Ltd.)

Long-term peritoneal dialysis induces peritoneal fibrosis with submesothelial fibrotic tissue. Although angiogenesis and inflammatory mediators are involved in peritoneal fibrosis, precise molecular mechanisms are undefined. To study this, we used microarray analysis and compared gene expression profiles of the peritoneum in control and chlorhexidine gluconate (CG)-induced peritoneal fibrosis mice. One of the 43 highly upregulated genes was pleiotrophin, a midkine family member, the expression of which was also upregulated by the solution used to treat mice by peritoneal dialysis. This growth factor was found in fibroblasts and mesothelial cells within the underlying submesothelial compact zones of mice, and in human peritoneal biopsy samples and peritoneal dialysate effluent. Recombinant pleiotrophin stimulated mitogenesis and migration of mouse mesothelial cells in culture. We found that in wild-type mice, CG treatment increased peritoneal permeability (measured by equilibration), increased mRNA expression of TGF-β1, connective tissue growth factor and fibronectin, TNF-α and IL-1β expression, and resulted in infiltration of CD3-positive T cells, and caused a high number of Ki-67-positive proliferating cells. All of these parameters were decreased in peritoneal tissues of CG-treated pleiotrophin-knockout mice. Thus, an upregulation of pleiotrophin appears to play a role in fibrosis and inflammation during peritoneal injury.

Background: Recently, it has been reported that the serum concentration of IgG4, a minor component of IgG subclasses, is increased in autoimmune pancreatitis. However, data regarding IgG4 concentrations in other pancreatic or biliary diseases have been insufficient., Methods: Serum IgG4 was measured in 116 patients with pancreatic or biliary diseases (35 autoimmune pancreatitis, 24 chronic pancreatitis except autoimmune pancreatitis, 11 primary sclerosing cholangitis, 23 pancreatic cancer, 3 islet cell tumor, 2 papilla cancer, 15 bile duct cancer, and 3 gallbladder cancer patients). The cut-off concentration of IgG4 was 135 mg/dl., Results: Increased serum IgG4 was observed in 33 of 35 patients with autoimmune pancreatitis, 0 of 24 with chronic pancreatitis, 4 of 11 with primary sclerosing cholangitis, 0 of 23 with pancreatic cancer, 0 of 3 with islet cell tumor, 0 of 2 with duodenal papilla cancer, 0 of 15 with bile duct cancer and 0 of 3 with gallbladder cancer patients., Conclusions: Serum IgG4 was increased in autoimmune pancreatitis and was within normal limits for other pancreatic or biliary diseases except primary sclerosing cholangitis.

Background: Catalase is one of the important antioxidant enzymes regulating the levels of intracellular hydrogen peroxide and hydroxyl radical. The effect of catalase deficiency on progressive renal fibrosis has not been fully elucidated., Methods: Homozygous acatalasemic mutant mice (C3H/AnLCs(b)Cs(b)) and control wild-type mice (C3H/AnLCs(a)Cs(a)) were subjected to 5/6 nephrectomy. The functional and morphological alterations of the remnant kidneys, including tubulointerstitial fibrosis, epithelial to mesenchymal transition (EMT), peroxidation, antioxidant enzyme activity, and gene expression of EMT-related molecules were compared between the two groups at 6, 12, and 18 weeks after 5/6 nephrectomy., Results: The 5/6 nephrectomy resulted in albuminuria, decreased renal function, and tubulointerstitial fibrosis with accumulation of type I and type IV collagens in the remnant kidneys of both mouse groups. However, the degree of these changes was significantly higher in acatalasemic mice after 5/6 nephrectomy as compared with wild-type mice until week 18. EMT, a crucial phenotypic alteration of tubular epithelial cells, was observed in acatalasemic mice by electron microscopy and was associated with upregulation of EMT-related alpha-smooth muscle actin (alpha-SMA), transforming growth factor-beta1 (TGF-beta1), connective tissue growth factor (CTGF), and fibroblast specific protein-1 (FSP-1) gene expression. Significant increases in the tubulointerstitial deposition of lipid peroxidation products, including 4-hydroxy-2-nonenal and urinary excretion of 8-hydroxy-2'- deoxyguanosine were observed in the acatalasemic mice after 5/6 nephrectomy as compared with the wild-type mice. Glomerular sclerosis developed after tubulointerstitial injury in acatalasemic mice. The level of catalase activity remained low in the remnant kidneys of acatalasemic mice until week 18 without compensatory up-regulation of glutathione peroxidase or superoxide dismutase (SOD) activity. Finally, supplementation of a SOD mimetic tempol did not prevent peroxidation and tubulointerstitial fibrosis in the acatalasemic remnant kidneys., Conclusion: These findings indicate that acatalasemia exacerbates renal oxidant tissue injury and sensitizes remnant kidneys to EMT and progressive renal fibrosis. This study suggests a central role for catalase in the defense against oxidant-mediated renal fibrosis.

Study Objective: During inferior acute myocardial infarction (AMI), the ECG lead aVR is frequently ignored, and therefore its clinical significance remains unclear. We examined the relation between ST-segment deviation seen in lead aVR on ECGs obtained at hospital admission and myocardial reperfusion in patients who have experienced recanalized inferior AMIs., Design and Setting: Retrospective study., Patients: A total of 225 patients with inferior AMIs in whom Thrombolysis in Myocardial Infarction grade 3 flow was achieved within 6 h after symptom onset., Measurements and Results: Patients were classified as follows according to ST-segment deviation in lead aVR on an ECG obtained at hospital admission: group A, 103 patients with no ST-segment depression; group B, 80 patients with ST-segment depression of < or = 1.0 mm; and group C, 42 patients with ST-segment depression of > 1.0 mm. There were no differences in time from symptom onset to hospital admission or in the culprit lesion among the three groups. The degree of ST-segment elevation in leads II, III, aVF, V5, or V6, the degree of ST-segment depression in leads V1 to V4, and the sum of ST-segment deviation in these leads were lowest in group A and highest in group C. In groups A, B, and C, the incidence of impaired myocardial reperfusion, defined as myocardial blush grade 0/1, was 2%, 23%, and 67%, respectively (p < 0.001). The sensitivity and negative predictive values of ST-segment depression in lead aVR for impaired myocardial reperfusion were higher than those based on other ECG variables. Multivariate analysis showed that the degree of ST-segment depression in lead aVR was an independent predictor of impaired myocardial reperfusion (odds ratio 8.41; 95% confidence interval, 2.96 to 23.9; p < 0.001)., Conclusions: We conclude that the degree of ST-segment depression in lead aVR is a useful predictor of impaired myocardial reperfusion in patients who have experienced inferior AMIs.

Objectives: Several pathological studies have shown that a higher ratio of the serum total cholesterol concentration to the high-density lipoprotein cholesterol concentration (TC/HDL-C ratio) is associated with plaque rupture in patients with acute coronary syndromes. We examined the relationship between the serum total cholesterol concentration and the TC/HDL-C ratio, and clinical and angiographic findings in patients with first acute myocardial infarction., Methods: Two hundred eighty patients were classified into quartiles according to the TC/HDL-C ratio measured within 24 hr from symptom onset: 70 patients in the first quartile (group L: mean TC/HDL-C ratio, 3.0), 140 in the second and third quartiles (group M: mean TC/HDL-C ratio, 4.6), and 70 in the fourth quartile (group H: mean TC/HDL-C ratio, 7.5)., Results: There were no differences among the three groups with regard to sex, diabetes mellitus or hypertension. Patients in group L were older (66 +/- 9 vs 60 +/- 11, 56 +/- 10 years, p < 0.01) and had a higher incidence of stable angina before acute myocardial infarction (26% vs 14%, 10%, p < 0.05) than in patients groups M and H. Although coronary angiograms revealed no difference in the number of diseased vessels among the three groups, extent index indicating the proportion of each coronary segment that appears angiographically abnormal was lowest in group L (0.7 +/- 0.5), followed by group M (1.3 +/- 0.6), and high- est in group H ( 1.7 +/- 0.6, p < 0.01). The number of segments with calcification and the incidence of calcification in the culprit lesion were higher in group L than in groups M and H., Conclusions: Our findings suggest that the clinical presentations and angiographic appearances differ according to the TC/HDL-C ratio in the acute phase of acute myocardial infarction.

Background: Sore throat and hoarseness are common complications, but these have not been studied after total i.v. anaesthesia., Methods: We prospectively studied 418 surgical patients, aged 15-92 yr, after total i.v. anaesthesia with propofol, fentanyl and ketamine to assess possible factors associated with sore throat and hoarseness., Result: We found sore throat in 50% and hoarseness in 55% of patients immediately after surgery. This decreased to 25% for sore throat and 24% for hoarseness on the day after surgery. Both sore throat and hoarseness were more common in females and when lidocaine spray had been used. Cricoid pressure during laryngoscopy was inversely associated with the risk of sore throat., Conclusion: Knowledge of these factors may reduce postoperative throat complications, and improve patient satisfaction.

A simple and sensitive assay and a cellular bioimaging method for nitric oxide (NO) were developed using a novel diaminofluorescein DAF-FM and its diacetate. DAF-FM is converted via an NO-specific mechanism to an intensely fluorescent triazole derivative. For the measurement of NO, the triazole derivative of DAF-FM was determined by reversed-phase high-performance liquid chromatography with fluorescence detection. In the presence of 1 microM DAF-FM, the concentrations of NOR-1, an NO donor, in the range of 2-200 nM were linearly related to the fluorescence intensity. This sensitive NO assay enabled us to detect the spontaneous and substance P-induced NO release from isolated porcine coronary arteries, both of which were dependent entirely on the NO synthase activity in vascular endothelial cells. We also obtained fluorescence images of cultured smooth muscle cells of the rat urinary bladder after loading with DAF-FM diacetate. In the cells pretreated with cytokines, the fluorescence intensity increased with time after DAF-FM loading. This increase in the fluorescence intensity was blocked by prior treatment of the muscle cells with an NO synthase inhibitor, N(G)-nitro-l-arginine methyl ester. Therefore, the present novel diaminofluorescein fluorometry should be useful not only for sensitive NO assay, but also for NO imaging in a variety of biological specimens., (Copyright 2000 Academic Press.)

Objective: Prostaglandins liberated from the uterus in response to chemical and physical stimuli would be important modulators of uterine arterial tone and blood flow. This study was aimed at analyzing mechanisms of vasodilator action of prostaglandins in uterine arteries., Study Design: Canine uterine artery strips were suspended in Ringer-Locke solutions for isometric tension recording., Results: Prostaglandin F2 alpha-induced relaxation was reversed to contraction by cyclooxygenase inhibitors and suppressed by tranylcypromine (prostaglandin I2 synthesis inhibitor) or diphloretin phosphate (an inhibitor of prostaglandin F2 alpha and prostaglandin I2 actions) but was unaffected by endothelium denudation. Prostaglandin E2-induced relaxation was not attenuated by indomethacin but was partially inhibited by a nitric oxide synthase inhibitor and endothelium denudation. Relaxation induced by beraprost (prostaglandin I2 analog) was suppressed by diphloretin phosphate but was not influenced by indomethacin and endothelium denudation., Conclusion: It appears that prostaglandin F2 alpha-induced relaxation is mediated by prostaglandin I2 released from subendothelial tissues, whereas prostaglandin E2-induced relaxation is caused by release of endothelium-derived nitric oxide and also by an endothelium-independent mechanism.

Treatment with L-NG-monomethyl arginine (L-NMMA), an inhibitor of nitric oxide (NO) synthesis from L-arginine, suppressed the relaxant response of dog cerebral artery strips to transmural electrical stimulation and nicotine, as did oxyhemoglobin. The inhibition by L-NMMA was reversed or prevented by L-, but not D-, arginine. It is concluded that NO or an NO-related compound may play a crucial role in transmitting information from excited vasodilator nerves to cerebroarterial smooth muscle.

Treatment with L-NG-nitro-arginine (L-NA) inhibited the brady-kinin-induced relaxation, mediated via EDRF, in dog coronary artery strips partially contracted with prostaglandin F2 alpha; the inhibition was prevented by L-, but not D-, arginine. Relaxation caused by nitroglycerin was not altered by L-NA. The release of EDRF, as assayed using dog coronary artery strips without endothelium, from perfused femoral artery segments with endothelium in response to acetylcholine and substance P was significantly reduced by treatment of the femoral artery with L-NA. The inhibitory effect was reversed by L-arginine. Relaxant responses of dog cerebral artery strips with and without endothelium to electrical stimulation of non-adrenergic, non-cholinergic nerves were suppressed by L-NA, whereas relaxation of coronary arteries with and without endothelium by the stimulation of adrenergic nerves was not influenced. The L-NA-induced inhibition was reversed by L-arginine. It is speculated that L-NA inhibits the synthesis of EDRF, as does L-NG-monomethyl arginine, and NO-like substance(s) produced plays an important role in transferring information from vasodilator nerves to smooth muscle in cerebral arteries.

Two compounds forming oxygen radicals were isolated from heated starch by monitoring the potency to form 8-hydroxydeoxyguanosine from deoxyguanosine during purification procedures. These compounds were identified as hydroxymethylreductic acid and methylreductic acid. The former compound was mutagenic to Salmonella strains TA100, TA102 and TA104 and the latter compound induced sister-chromatid exchanges in human NL3 cells. Hydroxymethylreductic acid was found to be a novel compound. Considerable amounts of these compounds were detected in various heat-processed foods.

Dog, monkey and human aortic tissues contained two distinct types of angiotensin II-generating enzymes; angiotensin converting enzyme (ACE) and chymostatin-sensitive angiotensin II-generating enzyme (CAGE). Endothelium, media and adventitia of canine thoracic aortae were separated using collagenase digestion, and determined for their ACE and CAGE activity. ACE activity was assayed by hippuryl-His-Leu cleavage. CAGE activity was estimated with ANG I as substrate in the presence of inhibitors of ACE and angiotensinases. His-Leu, the common product of both enzyme reactions, was fluorimetrically quantified after o-phthalaldehyde condensation. ACE localized mainly in endothelium, while CAGE distributed predominantly in adventitia. Similar results were obtained with human and monkey aortae. Such a contrasting distribution may indicate the distinct functional role of these two enzymes.