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Background: Cefmetazole (CMZ) is a carbapenem-sparing option in the treatment of extended-spectrum beta-lactamase (ESBL)-producing bacterial infection. In this pilot study, we aimed to compare the effects of antimicrobial treatment (meropenem [MP] and CMZ) with those of no antimicrobial treatment (control group) on the microbiome., Methods: The study was a multicenter, prospective, observational pilot study conducted from October 2020 to October 2022. Feces and saliva samples were collected for microbiome analyses at two time points (early-period: days 1-3; and late-period: days 4-30) for the antimicrobial treatment group, and at one time point for the control group., Results: Five feces (MP-F and CMZ-F) and five saliva (MP-S and CMZ-S) samples were included in the MP and the CMZ groups. Ten feces (C-F) and saliva (C-S) samples were included in the control group. Group α diversity was notably lower in the late-period MP-F group than the control group as determined with the Shannon richness index. β diversity analysis of the feces samples based on weighted and unweighted UniFrac distances revealed distinctions in both the late-period CMZ-F and MP-F groups compared with the control group. Weighted UniFrac analysis showed that only the early-period MP-F group differed from the control group. In the saliva samples, weighted and unweighted UniFrac analyses showed significant differences between the control group and the early CMZ, late CMZ, and late MP groups., Conclusions: MP treatment may cause larger impact on the feces microbiome than CMZ in Japanese patients., Competing Interests: Declaration of competing interest None to declare., (Copyright © 2024 Japanese Society of Chemotherapy, Japanese Association for Infectious Diseases, and Japanese Society for Infection Prevention and Control. Published by Elsevier Ltd. All rights reserved.)

Osteoclasts are hematopoietic cells attached to the bones containing type I collagen-deposited hydroxyapatite during bone resorption. Two major elements determine the stiffness of bones: regular calcified bone (bone that is resorbable by osteoclasts) and un-calcified osteoid bone (bone that is un-resorbable by osteoclasts). The osteolytic cytokine RANKL promotes osteoclast differentiation; however, the roles of the physical interactions of osteoclasts with calcified and un-calcified bone at the sealing zones and the subsequent cellular signaling remain unclear. In this study, we investigated podosomes, actin-rich adhesion structures (actin-ring) in the sealing zone that participates in sensing hard stiffness with collagen in the physical environment during osteoclast differentiation. RANKL-induced osteoclast differentiation induction was promoted when Raw264.7 cells were cultured on collagen-coated plastic dishes but not on non-coated plastic dishes, which was associated with the increased expression of podosome-related genes and Src. In contrast, when cells were cultured on collagen gel, expression of podosome-related genes and Src were not upregulated. The induction of podosome-related genes and Src requires hard stiffness with RGD-containing substratum and integrin-mediated F-actin polymerization. These results indicate that osteoclasts sense both the RGD sequence and stiffness of calcified collagen through their podosome components regulating osteoclast differentiation via the c-Src pathway., 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 © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: The adenosine triphosphate (ATP) assay is widely used for simple and rapid evaluation of the cleanliness of environmental surfaces. However, there remain concerns regarding the reliability of the ATP assay in hospital settings. This study aimed to assess whether the ATP assay could detect inadequate cleaning within hospital environments as well as monitor the effectiveness of routine cleaning., Methods: The cleanliness of seven types of high-touch surfaces in operating rooms that were routinely cleaned was evaluated by testing the ATP assay and aerobic colony counts (ACC). For pressure redistribution mattresses (Soft-nurse®) that were found to be particularly at risk of infection, cleaning methods were improved, and the effectiveness of these improvements was monitored using the same two methods., Results: The ATP assay quantitatively detected contamination on seven high-touch surfaces but showed no correlation with ACC. However, a significant positive correlation between luminescence and ACC was found on one specific surface, allowing for determining a theoretical cutoff value. Additionally, the ATP assay effectively identified the risk of future infection, which the ACC test could not assess., Conclusions: The ATP assay can monitor the effectiveness of routine cleaning by setting a theoretical cutoff value for each subject. The method provides quantitative and meaningful values when used with an understanding of its limitations., (Copyright © 2023 Australasian College for Infection Prevention and Control. Published by Elsevier B.V. All rights reserved.)

Prostate cancer highly metastasizes to bone, and such cancer is associated with severe bone resorption and bone formation at the site of metastasis. Prostaglandin E 2 (PGE 2 ) promotes bone resorption in inflammatory diseases; however, the roles in prostate cancer-induced bone formation are still unclear. In the present study, we investigated the effects of membrane-bound TGF-α on prostate cancer-induced bone formation through autocrine PGE 2 signaling in osteoblasts. In the prostate cancer explant experiment into tibiae, injected prostate cancer cells induced bone formation with the increased expression of osteogenic genes, such as Runx2 and Wnt5a, and prostaglandin synthase Ptgs2. In osteoblasts, PGE 2 increased the number of calcified bone nodules with enhanced expression of Runx2 and Wnt5a. We also screened the factors involved in cancer progression, and 11 EGF family members were found to be expressed in the human prostate cancer cell line PC3. PC3 highly expressed amphiregulin, HB-EGF, and especially TGF-α. Treatment with recombinant TGF-α increased the Ptgs2 expression and PGE 2 production in osteoblasts, which promoted the formation of calcified bone nodules, suggesting that the interaction between PC3 and osteoblasts promoted PGE 2 production. In co-culture of osteoblasts and fixed PC3 cells, the phosphorylation of EGFR and ERK and subsequent Ptgs2 expression and PGE 2 production were increased, an effect that was attenuated by treatment with inhibitors of EGFR and ERK. These results indicate that membrane-bound TGF-α enhances ERK signaling while also inducing PGE 2 -mediated bone formation in osteoblasts, thus suggesting that prostate cancer regulates both PGE 2 -mediated bone resorption and bone formation at the site of bone metastasis of prostate cancer., 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 © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Objectives: To alleviate the overflow of coronavirus disease 2019 (COVID-19) patients in hospitals, less invasive and simple criteria are required to triage the patients. We evaluated the relationship between COVID-19 severity and fatty liver on plain computed tomography (CT) scan performed on admission., Methods: In this retrospective cohort study, we considered all COVID-19 patients at a large tertiary care hospital between January 31 and August 31, 2020. COVID-19 severity was categorized into severe (moderate and severe) and non-severe (asymptomatic and mild) groups, based on the Japanese National COVID-19 guidelines. Fatty liver was detected on plain CT scan. Multivariate logistic regression analysis was performed to evaluate factors associated with severe COVID-19., Results: Of 222 patients (median age: 52 years), 3.2%, 58.1%, 20.7%, and 18.0% presented with asymptomatic, mild, moderate, and severe COVID-19, respectively. Although 59.9% had no fatty liver on plain CT, mild, moderate, and severe fatty liver occurred in 13.1%, 18.9%, and 8.1%, respectively. Age and presence of fatty liver were significantly associated with severe COVID-19., Conclusion: Our study showed that fatty liver on plain CT scan on admission can become a risk factor for severe COVID-19. This finding may help clinicians to easily triage COVID-19 patients., (Copyright © 2021 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Introduction: The ability to predict which patients with a history of coronavirus disease (COVID-19) will exhibit a high antibody titer is necessary for more efficient screening of potential convalescent plasma donors. We aimed to identify factors associated with a high immunoglobulin G (IgG) titer in Japanese convalescent plasma donors after COVID-19., Methods: This cross-sectional study included volunteers undergoing screening for convalescent plasma donation after COVID-19. Serum anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) S-protein IgG antibodies were measured using a high-sensitivity chemiluminescence enzyme immunoassay., Results: IgG antibodies were measured in 581 patients, 534 of whom had full information of selected independent variables. Multiple linear regression analysis revealed that increasing age (1.037 [1,025, 1.048]), days from symptom onset to sampling (0.997 [0.995, 0.998]), fever (1.664 [1.226, 2.259]), systemic corticosteroid use during SARS-CoV-2 infection (2.382 [1.576, 3.601]), and blood type AB (1.478 [1.032, 2.117]) predict antibody titer., Conclusion: Older participants, those who experienced fever during infection, those treated with systemic corticosteroids during infection, those from whom samples were obtained earlier after symptom onset, and those with blood type AB are the best candidates for convalescent plasma donation. Therefore, these factors should be incorporated into the screening criteria for convalescent plasma donation after SARS-CoV-2 infection., (Copyright © 2021 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Introduction: "Re-infection" with COVID-19 is a growing concern; re-infection cases have reported worldwide. However, the clinical characteristics of SARS-CoV-2 re-infection, including the levels and role of anti-SARS-CoV-2 Spike protein IgG antibodies and the half-maximal concentration (IC 50 ) of neutralizing antibodies remain unknown., Methods: Both the epidemiological and clinical information has been collected during two episodes of COVID-19 in a patient. Laboratory results, including RT-PCR, Ct values, anti-SARS-CoV-2 Spike protein IgG antibodies, and the IC 50 of neutralizing antibodies levels were analyzed on the patient., Results: The patient was a 58-year-old man who developed moderate COVID-19 pneumonia with oxygen demand (cannula 2 L/min) in the first episode. By day 30, he recuperated and was discharged after testing negative for SARS-CoV-2. After two and a half months, his three family members showed COVID-19 symptoms and tested positive for SARS-CoV-2. He tested positive for SARS-CoV-2 once again and was asymptomatic (the second episode). The IC 50 of neutralizing antibodies against SARS-CoV-2 greatly increased from 50.0 μg/mL (after the first episode) to 14.8 μg/mL (after the second episode), and remained strongly reactive (20.1 μl/mL) after 47 days of the second episode., Conclusions: Epidemiological, clinical, and serological analyses confirmed that the patient had re-infection instead of persistent viral shedding from first infection. Our results suggest that SARS-CoV-2 re-infection may manifest as asymptomatic with increased neutralizing antibody levels. Further studies such as the virus characteristics, immunology, and epidemiology on SARS-CoV-2 re-infection are needed., (Copyright © 2021 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Introduction: Convalescent plasma transfusion (CPT), a potential therapy for coronavirus disease 2019 (COVID-19), requires strict quality control of the donor blood. Whether to confirm the disappearance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA (RNAemia) in convalescent donor blood or not is unclear. Reports recommending the proof of viral disappearance from the blood are controversial. Foreseeing CPT in treating COVID-19 patients in Japan, we investigated RNAemia in 100 convalescent donors with mild, moderate, and severe COVID-19., Methods: Between April 30 and July 30, 2020, we measured RNAemia in the plasma samples of donors with resolved COVID-19. Data on patients' demographics, comorbidities, pneumonia, treatment, and real-time polymerase chain reaction results for SARS-CoV-2 were collected. Date of onset of initial symptoms or date of positive testing (for asymptomatic patients) were self-reported by the patients. Disease severity was defined as: no, mild, moderate oxygen demand, or severe (requiring mechanical ventilation)., Results: Of 100 donors (58 males [58.0%]; median age, 47 [range 22-69] years) screened as of July 30, 2020, 77 (77.0%); 19 (19.0%); and 4 (4.0%) had mild, moderate, and severe disease, respectively. Median time between onset and testing was 68.5 (range, 21-167) days. SARS-CoV-2 RNA was not detected in any of the plasma samples., Conclusion: RNAemia was not found in recovered COVID-19 patients at least 21, 27, and 57 days after the onset of mild, moderate, and severe symptoms. Our study may contribute to determining a suitable time for collecting convalescent plasma from COVID-19 patients and to future CPT use., Competing Interests: Declaration of competing interest None., (Copyright © 2021 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Dupuytren's Disease (DD) is a common fibroproliferative disease of the palmar fascia. We previously identified a causal association with a non-synonymous variant (rs1042704, p.D273N) in MMP14 (encoding MT1-MMP). In this study, we investigated the functional consequences of this variant, and demonstrated that the variant MT1-MMP (MT1-N 273 ) exhibits only 17% of cell surface collagenolytic activity compared to the ancestral enzyme (MT1-D 273 ). Cells expressing both MT1-D 273 and MT1-N 273 in a 1:1 ratio, mimicking the heterozygous state, possess 38% of the collagenolytic activity compared to the cells expressing MT1-D 273 , suggesting that MT1-N 273 acts in a dominant negative manner. Consistent with the above observation, patient-derived DD myofibroblasts with the alternate allele demonstrated around 30% of full collagenolytic activity detected in ancestral G/G genotype cells, regardless of the heterozygous (G/A) or homozygous (A/A) state. Small angle X-ray scattering analysis of purified soluble Fc-fusion enzymes allowed us to construct a 3D-molecular envelope of MT1-D 273 and MT1-N 273 , and demonstrate altered flexibility and conformation of the ectodomains due to D 273 to N substitution. Taking together, rs1042704 significantly reduces collagen catabolism in tissue, which tips the balance of homeostasis of collagen in tissue, contributing to the fibrotic phenotype of DD. Since around 30% of the worldwide population have at least one copy of the low collagenolytic alternate allele, further investigation of rs1042704 across multiple pathologies is needed., Competing Interests: Declaration of Competing Interest The authors declare no competing interests., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Although interactions between lipids and membrane proteins (MPs) have been considered crucially important for understanding the functions of lipids, lack of useful and convincing experimental methods has hampered the analysis of the interactions. Here, we developed a surface plasmon resonance (SPR)-based concise method for quantitative analysis of lipid-MP interactions, coating the sensor chip surface with self-assembled monolayer (SAM) with C 6 -chain. To develop this method, we used bacteriorhodopsin (bR) as an MP, and examined its interaction with various types of lipids. The merits of using C 6 -SAM-modified sensor chip are as follows: (1) alkyl-chains of SAM confer a better immobilization of MPs because of the efficient preconcentration due to hydrophobic contacts; (2) SAM provides immobilized MPs with a partial membranous environment, which is important for the stabilization of MPs; and (3) a thinner C 6 -SAM layer (1 nm) compared with MP size forces the MP to bulge outward from the SAM surface, allowing extraneously injected lipids to be accessible to the hydrophobic transmembrane regions. Actually, the amount of bR immobilized on C 6 -SAM is 10 times higher than that on a hydrophilic CM5 sensor chip, and AFM observations confirmed that bR molecules are exposed on the SAM surface. Of the lipids tested, S-TGA-1, a halobacterium-derived glycolipid, had the highest specificity to bR with a nanomolar dissociation constant. This is consistent with the reported co-crystal structure that indicates the formation of several intermolecular hydrogen bonds. Therefore, we not only reproduced the specific lipid-bR recognition, but also succeeded in its quantitative evaluation, demonstrating the validity and utility of this method., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The interaction of high mobility group box 1 (HMGB1), which is secreted from immune and dying cells during cellular infection and injury, and receptor for advanced glycation end-products (RAGE) appears to be critical for acute and chronic inflammatory disorders. Here we designed a unique cyclic β-hairpin peptide (Pepb2), which mimics the predicted RAGE-binding domain of HMGB1. Pepb2 competitively inhibited HMGB1/RAGE interaction. We then identified papaverine as a Pepb2 mimetic by in silico 3D-structural similarity screening from the DrugBank library. Papaverine was found to directly inhibit HMGB1/RAGE interaction. It also suppressed the HMGB1-mediated production of pro-inflammatory cytokines, IL-6 and TNF-α, in mouse macrophage-like RAW264.7 cells and bone marrow-derived macrophages. In addition, papaverine attenuated mortality in cecal ligation puncture-induced sepsis model mice. Taken together, these findings indicate that papaverine could become a useful therapeutic against HMGB1/RAGE-mediated sepsis and other inflammatory diseases., (Copyright © 2019 Elsevier Inc. All rights reserved.)

We have developed a novel voltammetric DNA chip for real-time electrochemical detection of targeted nucleic acid sequences using loop-mediated isothermal amplification (LAMP) and ruthenium hexaamine (RuHex) as the intercalative redox compound. A GspSSD DNA polymerase was used for LAMP owing to its tolerance of the intercalative redox compound. The electrochemical reaction of 1 mM RuHex in the LAMP solution was measured continuously by linear sweep voltammetry at 65 °C using an electrochemical DNA chip. According to the LAMP reaction of the positive sample, the cathodic peak current of RuHex increased and the cathodic peak potential of RuHex shifted to negative voltage. The initial number of copies of the targeted nucleic acid was correlated with both the time when the cathodic current began to increase and the time when the cathodic potential began to shift rapidly. 10 3 to 10 6 copies/50 μL of the targeted nucleic acid were detected quantitatively and the detection limit was 10 1 copies within an hour. We expect these results to lead to the realization of simple and stable electrochemical real-time monitoring of targeted nucleic acids while also facilitating the implementation of electrochemical DNA chips in molecular testing., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The metastasis of tumors to bone is known to be promoted by prostaglandin E2 (PGE2) produced by the tumor host stromal tissue. Although bone metastases frequently occur in prostate cancer patients, the significance of PGE2 in stromal responses to the tumor is not known. In this study, we report that PGE2 and its receptor EP4 play a pivotal role in bone destruction and metastasis in an experimental metastasis model of prostate cancer in nude mice. Using human prostate cancer PC-3 cells that are stably transfected with luciferase, we showed that the development of bone metastasis was accompanied by increased osteoclastic bone resorption in the bone metastasis microenvironment, and could be abrogated by an EP4 receptor antagonist. The growth of PC-3 cells in vitro was not influenced by PGE2 or by the EP4 receptor. However, cell-cell interactions between fixed PC-3 cells and host osteoblasts induced PGE2 production and RANKL expression in the osteoblasts. Addition of an EP4 antagonist suppressed both PGE2 and RANKL expression induced by the PC3-osteoblast interaction, which would have consequent effects on osteoclast activation and osteolysis. These results indicate that the blockage of PGE2-EP4 signaling prevents the bone destruction required for prostate cancer metastases, and that this is, in part due to the abrogation of bone cell responses. The study provides further evidence that an EP4 antagonist is a candidate for the treatment of prostate cancer in the blockade of bone metastasis., (Copyright © 2016. Published by Elsevier Inc.)

Carboranes are a class of carbon-containing polyhedral boron cluster compounds with globular geometry and hydrophobic surface that interact with hormone receptors such as estrogen receptor (ER) and androgen receptor (AR). We have synthesized BA321, a novel carborane compound, which binds to AR. We found here that it also binds to ERs, ERα and ERβ. In orchidectomized (ORX) mice, femoral bone mass was markedly reduced due to androgen deficiency and BA321 restored bone loss in the male, whilst the decreased weight of seminal vesicle in ORX mice was not recovered by administration of BA321. In female mice, BA321 acts as a pure estrogen agonist, and restored both the loss of bone mass and uterine atrophy due to estrogen deficiency in ovariectomized (OVX) mice. In bone tissues, the trabecular bone loss occurred in both ORX and OVX mice, and BA321 completely restored the trabecular bone loss in both sexes. Cortical bone loss occurred in ORX mice but not in OVX mice, and BA321 clearly restored cortical bone loss due to androgen deficiency in ORX mice. Therefore, BA321 is a novel selective androgen receptor modulator (SARM) that may offer a new therapy option for osteoporosis in the male., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: The determination of gastric pH is important for the confirmation of efficacy of anti-secretory drugs. However, current methods for measurement of gastric pH provide significant stress to animals and humans., Aim: The objective of this study is to establish an easy and reliable gastric pH measurement method by determining (13)CO2 concentration in expired air of monkeys, dogs, and rats after oral administration of Ca(13)CO3., Methods: A correlation of (13)CO2 concentration determined by a Ca(13)CO3 breath test with gastric pH just before Ca(13)CO3 administration was analyzed in the 3 animal species. The equations and contribution ratios of regression line were calculated from logarithmic (13)CO2 concentrations at 15min after administration of Ca(13)CO3 using the linear regression analysis., Results: The (13)CO2 concentration in the Ca(13)CO3 breath test was well correlated with the gastric pH just before Ca(13)CO3 administration in the 3 animal species (r=-0.977 to -0.952). The equations of regression line between the (13)CO2 concentration and the gastric pH in each animal species showed good contribution ratios (R(2)≥0.89)., Conclusions: The Ca(13)CO3 breath test is an informative tool to estimate gastric pH in animals and will be applicable as a new noninvasive tool for patients with GERD/PPI-resistant symptoms., (Copyright © 2016 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.)

Hepatitis C virus (HCV) is a causative agent of chronic hepatitis. Although the standard therapy for HCV-infected patients consists of pegylated interferon plus ribavirin, this treatment is associated with serious side effects and high costs, and fails in some patients infected with specific HCV genotypes. To address this problem, we are developing small-molecule inhibitors of cyclin-dependent kinases (CDKs) as novel anti-HCV drug candidates. Previous data showed that HCV replication is inhibited by retinoblastoma protein, which is itself inactivated by CDK-mediated phosphorylation. Here, we report that CDK inhibitors suppress HCV replication in vitro and in vivo, and that CDK4 is required for efficient HCV replication. These findings shed light on the development of novel anti-HCV drugs that target host factors., (Copyright © 2014 Elsevier B.V. All rights reserved.)

TLR2 forms heterodimers with TLR1 and TLR6, and regulates host defense mechanisms against pathogens. We examined the role of TLR2 heterodimer signaling in osteoclast formation and inflammatory periodontitis. In co-cultures of mouse bone marrow cells and osteoblasts, a TLR2/6 ligand (diacylated lipopeptide designed from Gram-positive bacteria) markedly induced osteoclast formation. A TLR2/1 ligand (triacylated lipopeptide designed from Gram-negative bacteria) also induced osteoclast formation. The osteoclast formation induced by TLR2/6 and TLR2/1 ligands was completely suppressed by indomethacin. Osteoblasts expressed TLR1, 2, 4, and 6 mRNAs, and both TLR2/6 and TLR2/1 ligands induced the expression of COX-2, mPGES-1, and RANKL mRNA, as well as PGE production in osteoblasts. Both TLR2/6 and TLR2/1 ligands induced the resorption of mandibular alveolar bone in organ cultures, and elicited inflammatory periodontitis in vivo. Therefore, TLR2 heterodimer signaling may play a key role in PGE-mediated inflammatory bone loss in periodontal disease., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background: Corrected QT (QTc) interval prolongation can induce fatal arrhythmias such as torsade de pointes., Patients and Methods: To assess the characteristics of QTc intervals and arrhythmias in women with early breast cancer who received FEC100 adjuvant chemotherapy, electrocardiograms (ECGs) were recorded before and after each chemotherapy. Associations between QTc interval prolongation and single nucleotide polymorphisms (SNPs) of potassium channel genes were also investigated., Results: A total of 131 ECG records were obtained in 34 patients who received 153 cycles of FEC100. QTc intervals could be measured in 127 records. There was a significant trend toward QTc interval prolongation after each treatment, persisting through four cycles of chemotherapy (P < 0.001). Median QTc interval prolongations were 13, 11, 18, and 14 ms in the first through fourth cycles of chemotherapy, respectively. QTc intervals differed significantly between cycles 1 and 4 before treatment as well as after treatment (P < 0.05). A single supraventricular premature contraction was noted in 3 (2.3%) of the 131 cycles in 2 (5.9%) of the 34 patients. There was no significant association between QTc interval prolongation and SNPs of potassium channel genes., Conclusion: This prospective study confirmed that FEC100 is associated with significant QTc interval prolongation in women with early breast cancer.

(14)C-erythromycin breath test has been utilized to evaluate the extent of CYP3A activity in vivo. However, its radioactivity sometimes impedes its clinical application. In this study, we employed erythromycin labeled with (13)C ((13)C-EM), a nonradioactive stable isotope, as an in vivo probe of breath test to evaluate CYP3A-mediated drug interactions in rats. A physiologically based pharmacokinetic (PBPK) model to describe (13)CO(2) exhalation altered by drug interactions was newly constructed. Rats received an intravenous or oral administration of (13)C-EM with or without a CYP3A inhibitor or inducer, that is, ketoconazole (KCZ) or dexamethasone (DEX), respectively. Breath samples were taken at designated times, measured with an infrared spectrophotometer, and the Δ(13) CO(2) value (‰) in each sample was obtained. The C(max) and AUC(0-t) of Δ(13) CO(2) were significantly decreased with KCZ and increased with DEX. The PBPK model in this study successfully described the (13)CO(2) exhalation after (13)C-EM administration in the absence and presence of drug interactions. In conclusion, this study proposed a simple and rapid in vivo methodology to utilize (13)C-EM for the quantitative analysis of CYP3A inhibition and induction. This method using small animals may be useful in early drug development processes., (Copyright © 2011 Wiley-Liss, Inc.)

This paper describes a method for determination of multiwall carbon nanotubes (MWCNTs) in rat lungs after intratracheal instillation exposure. The MWCNTs were quantitatively decomposed to CO(2) by combustive oxidation and were then determined by non-dispersive infrared analysis. Samples were pretreated by acid digestion, muffle ashing and in situ preheating to remove interferences due to coexisting biological carbon from the lung tissue sample, while preserving the MWCNTs as in its their original form. The preservation was confirmed by transmission electron microscopic observation of the pretreated samples of exposed lung tissues and by the fact that the recoveries of MWCNTs spiked to the lung tissues were close to 100%. The detection limit for MWCNTs obtained by the proposed method was 0.30 μg and the repeatability as expressed by the relative standard deviation was 5.6% (n=4). The method was sufficiently sensitive and precise to apply to real samples of rat lung to investigate the in vivo persistence of intratracheally instilled MWCNTs. To our knowledge, this is the first report of this type of sample pretreatment and direct determination of pristine MWCNTs without modification or tagging. Conventional indirect methods use tagging with other compounds or metal impurities in the CNTs for detection, and the detachment of these tags can increase uncertainties in the determination of the CNTs. The tags can also change how the CNTs persist in vivo, which can lead to an incorrect understanding of the persistence of pristine CNTs in vivo., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Background & Aims: This study investigated the efficacy and adverse effects of pegylated interferon (Peg-IFN) plus ribavirin therapy in aged patients with chronic hepatitis C (CH-C)., Methods: A total of 1040 naïve patients with CH-C (genotype 1, n=759; genotype 2, n=281), of whom 240 (23%) over 65 years old (y.o.), were treated with Peg-IFN alfa-2b plus ribavirin and assessed after being classified into five categories, according to age., Results: The discontinuance rate was higher for patients over 70 y.o. (36%), the most common reason being anemia. In the presence of genotype 1, the SVR rate was similar (42-46%) among patients under 65 y.o. and declined (26-29%) among patients over 65 y.o. For patients over 65 y.o., being male (Odds ratio, OR, 3.5, p=0.035) and EVR (OR, 83.3, p<0.001) were significant factors for SVR, in multivariate analysis. The Peg-IFN dose was related to EVR, and when EVR was attained, 76-86% of patients over 65 y.o. achieved SVR. SVR was not achieved (0/35, 0/38, respectively) if a 1-log decrease and a 2-log decrease were not attained at week 4 and week 8, respectively. In the presence of genotype 2, the SVR rate was similar (70-71%) among patients under 70 y.o. and declined among patients over 70 y.o. (43%)., Conclusions: Aged patients up to 65 y.o. with genotype 1 and 70 y.o. with genotype 2 can be candidates for Peg-IFN plus ribavirin therapy. The response-guided therapy can be applied for aged patients with genotype 1., (Copyright © 2010 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.)

Hyaluronan (HA), a large glycosaminoglycan, is a component of the extra-cellular matrix in various tissues. HA is essential for matrix assembly and fluid viscosity in cartilage, but the roles of HA in bone are unclear. Bone resorption associated with inflammation is closely related to prostaglandin E (PGE) synthesis by osteoblasts induced by cytokines such as interleukin-1 (IL-1). In mouse calvarial cultures, HA inhibited osteoclastic bone resorption and PGE production induced by IL-1. In mouse osteoblasts, HA suppressed IL-1-induced expression of cyclooxygenase(COX)-2 and membrane-bound PGE synthase (mPGES)-1 mRNAs, and PGE2 production. Matrix metalloproteinases (MMPs), including MMP-2 and MMP-13, were produced by osteoblasts in response to IL-1, and were clearly suppressed by HA. In osteoblasts, HA suppressed the NFkappaB-dependent transcription in a luciferase assay. Therefore, HA acts on osteoblasts to suppress the production of PGE2 and MMPs, and inhibits bone resorption, suggesting critical roles of HA in pathological bone loss with inflammation.

Carboranes are a class of carbon-containing polyhedral boron-cluster compounds with globular geometry and hydrophobic surface that interact with hormone receptors. Estrogen deficiency results in marked bone loss due to increased osteoclastic bone resorption in females, but estrogen replacement therapy is not generally used for postmenopausal osteoporosis due to the risk of uterine cancer. We synthesized a novel carborane compound BE360 to clarify its anti-osteoporosis activity. BE360 showed a high binding affinity to estrogen receptors (ER), ERalpha and ERbeta. In ovariectomized (OVX) mice, femoral bone volume was markedly reduced and BE360 dose-dependently restored bone loss in OVX mice. However, BE360 did not exhibit any estrogenic activity in the uterus. BE360 also restored bone loss in orchidectomized mice without androgenic action in the sex organs. Therefore, BE360 is a novel selective estrogen receptor modulator (SERM) that may offer a new therapy option for osteoporosis.

Novel vitamin D analogs, 1alpha, 25-dihydroxyvitamin D(3)-26, 23-lactam (DLAMs) with a lactam moiety in the side chain, were synthesized and examined for their function in bone. In computer docking simulation, DLAM-1P binds to vitamin D receptor (VDR), and its lactam moiety may interfere with VDR helix-12 folding. In co-cultures of mouse bone marrow cells and osteoblasts, (23S,25S)-DLAM-1P dose-dependently suppressed osteoclast differentiation induced by 1alpha, 25-dihydroxyvitamin D(3) [1alpha, 25(OH)(2)D(3)]. Its stereoisomer (23R,25R)-DLAM-1P did not affect the osteoclast differentiation. In osteoblasts, (23S,25S)-DLAM-1P suppressed 1alpha, 25(OH)(2)D(3)-induced mRNA expression of the receptor activator of NF-kappaB ligand (RANKL). In an organ culture using mouse calvaria, bone-resorbing activity induced by 1alpha, 25(OH)(2)D(3) was clearly suppressed by (23S,25S)-DLAM-1P. The other analog, (23S,25S)-DLAM-2P, showed a similar activity to (23S,25S)-DLAM-1P. Therefore, DLAMs act on osteoblasts as an antagonist of 1alpha, 25(OH)(2)D(3) to suppress RANKL-dependent osteoclast formation, suggesting them as a novel candidate for the treatment of pathological bone loss.

Treatment of acute or chronic liver diseases by cell transplantation is an attractive prospect because organ shortages greatly restrict liver transplantation. Moreover, a variety of genetic deficiency states affecting extrahepatic organs are amenable to liver-directed cell therapy. While the initial clinical experience with liver cell transplantation has been encouraging, further advances in several areas are necessary to improve these results. Insights into how engraftment and proliferation of transplanted cells may be modulated to obtain therapeutically effective masses of transplanted cells will be important in this pursuit. Studies of cell therapy in animal models of specific diseases have provided insights into the development of clinically relevant strategies for various disorders. Also, identification of suitable cell types, including stem/progenitor cells that could be expanded and manipulated in cell culture conditions, has begun to provide important new information for cell therapy. Similarly, advances in cryopreservation of cells and prevention of allograft rejection offer ways to accomplish cell therapy in an effective manner. Taken together, these advances indicate that liver-directed cell therapy will be well positioned in the near future to play significant roles in transplantation medicine., (Copyright 2004 Elsevier B.V.)

Background: Carboranes (dicarba-closo-dodecaboranes) are a class of carbon-containing polyhedral boron-cluster compounds having remarkable thermal stability and exceptional hydrophobicity. Applications of the unique structural and chemical properties offered by icosahedral carboranes in boron neutron capture therapy have received increasing attention over the past 30 years. However, these features of carboranes may allow another application as a hydrophobic pharmacophore in biologically active molecules that interact hydrophobically with receptors., Results: We have designed candidate estrogen-receptor-binding compounds having carborane as a hydrophobic skeletal structure and synthesized them. The most potent compound bearing a carborane cage exhibited activity at least 10-fold greater than that of 17beta-estradiol in the luciferase reporter gene assay. Estrogen receptor-alpha-binding data for the compound were consistent with the results of the luciferase reporter gene assay. The compound also showed potent in vivo effects on the recovery of uterine weight and bone loss in ovariectomized mice., Conclusion: Further development of the potent carborane-containing estrogenic agonists described here, having a new skeletal structure and unique characteristics, should yield novel therapeutic agents, especially selective estrogen receptor modulators. Furthermore, the suitability of the spherical carborane cage for binding to the cavity of the estrogen receptor-alpha ligand-binding domain should provide a basis for a similar approach to developing novel ligands for other steroid receptors.

Deficiency of sex steroids causes osteoporosis, but the relationship between estrogen and androgen is not clear because androgen is converted into estrogen by aromatase. In this study, we characterized bone metabolism in the aromatase-deficient (ArKO) mouse. At 9 weeks old, a marked loss of cancellous bone due to increased bone resorption was observed not only in female ArKO mice but also in males. The degree of bone loss in ArKO males was similar to that in females, and treatment with 17beta-estradiol completely restored the bone mass in both sexes. At 32 weeks old, female ArKO mice showed severe loss of cancellous and cortical bone. Male ArKO mice of this age also showed reduced bone mass, but the degree of bone loss in females was more marked than that in males. Here, we report sex- and age-related responses to aromatase deficiency in bone., (Copyright 2001 Academic Press.)

Although cigarette smoking is known to be a strong risk factor for the development of coronary artery disease, several large clinical studies have demonstrated that current smokers had a favorable prognosis compared to nonsmokers after myocardial infarction. This study sought to evaluate the effect of smoking status on heart rate variability after onset of acute myocardial infarction. We studied 52 patients (34 smokers, 18 nonsmokers) with a first myocardial infarction within 24 h of onset. We recorded 24-h ambulatory ECG to calculate very low frequency power (VLF), low frequency power (LF) and high frequency power (HF) 14 days after onset. Although smokers had a tendency to be younger than nonsmokers (mean age 57 versus 62, P = 0.0812), clinical characteristics were not statistically different between smokers and nonsmokers. After adjustment for age, left ventricular ejection fraction, history of diabetes, acute revascularization and use of beta-blockers, VLF (P = 0.0183) of smokers 14 days after onset was significantly higher than for nonsmokers. In conclusion, although smoking reduces heart rate variability in the general population, higher heart rate variability was observed in smokers than nonsmokers after acute myocardial infarction under the condition of smoking cessation.

Cbfa1, a transcriptional factor that belongs to the runt-domain gene family, plays a pivotal role in osteogenesis. Cbfa1-deficient mice completely lacked both intramembranous and endochondral bone formation owing to the maturational arrest of osteoblasts, resulting in a total lack of bone marrow throughout the entire skeleton. To investigate the development of hematopoiesis in Cbfa1-deficient mice, hematopoietic tissues and peripheral blood were examined. Colony-forming assays of yolk sac at embryonic day 10.5 (E10.5) and liver at E12.5 showed normal numbers of hematopoietic precursors in the mutant embryos. Further, histological examination and flow-cytometric analysis showed normal hematopoietic development of liver and spleen in the mutant embryos until E17.5. However, mutant embryos at E18.5 showed large hematopoietic foci in the periportal area of liver and mild splenomegaly with dilated vessels, and an increase of myeloid cells was observed in both organs. Flow-cytometric analysis also demonstrated a relative increase of granulocytes and a relative decrease of B-cells reciprocally in the livers and spleens of the mutant embryos. Colony-forming assays showed that the frequency of colony-forming unit-culture (CFU-C) was elevated in liver, and both the frequency and total number of CFU-C were increased in spleen of mutant embryos at E18.5. Moreover, leukoerythroblastosis was observed in peripheral blood of the mutant embryos. These data demonstrate that the congenital lack of bone marrow caused excessive levels of extramedullary hematopoiesis in both liver and spleen at the late embryonic stage., (Copyright 1999 Academic Press.)

To evaluate the regulatory mechanism of human Type 1 iodothyronine deiodinase (D1) gene expression, we measured the D1 mRNA levels in peripheral blood mononuclear cells (PBMC) in normal control subjects and in patients with Graves' disease. We used competitive reverse transcriptase-polymerase chain reaction with the deleted complimentary RNA of D1 as the standard for quantification. The D1 mRNA levels in PBMC were increased significantly in patients with Graves' disease compared with that in normal controls. There was a significant (p < 0.01) positive correlation (r=0.698) between D1 mRNA level and serum T3 concentration. When PBMC from the normal volunteers were cultured with various doses of T3, the quantity of D1 mRNA increased significantly in a dose-dependent manner. These findings indicate that PBMC D1 mRNA is actually up-regulated by T3 in vivo, and we postulate that a vicious spiral of increasing T3 and D1 is responsible for the exacerbation of thyrotoxicosis in hyperthyroid Graves' disease., (Copyright 1998 Academic Press.)

The safety, findings and clinical usefulness of magnetic resonance (MR) imaging were assessed in patients with a prosthetic carbon valve in the mitral position. In vitro deflection, heating and image distortion due to the magnetic field of a 1.5 tesla MR machine were examined in three carbon valves (CarboMedics, St. Jude Medical and Björk-Shiley valves). In vivo MR imaging of the left ventricular horizontal long-axis, vertical long-axis and short-axis views was performed by electrocardiographically synchronized spin echo and field (gradient) echo techniques in eight patients with prosthetic mitral carbon valves, consisting of six CarboMedics valves, one St. Jude Medical valve and one Björk-Shiley valve. No deflection and significant heating was seen in all three valves in vitro. Although little image distortion was shown in the CarboMedics and St. Jude Medical valves, a small distortion toward the frequency encoded direction was seen in the Björk-Shiley valve but caused no difficulty in assessing the surrounding images. Four of the eight patients had normal sinus rhythm and the other four had atrial fibrillation. The prosthetic valves were depicted as signal voids in the images taken by both spin echo and field echo techniques in vivo. Clear structural information with little image distortion of the adjacent tissues of the prosthetic valves were obtained in all patients, although the image of the Björk-Shiley valve which contained stainless steel in the frame had a slightly stronger distortion than those of the CarboMedics and St. Jude Medical valves which contained titanium. The stainless wire suture material used to close the sternal incision was depicted as a signal void, and the areas of the signal loss were larger in the images taken by the field echo technique than those by the spin echo technique. The images taken by the spin echo technique in patients with atrial fibrillation had reduced quality due to the irregularity of repetition time. Cine MR imaging by the field echo technique showed physiological mitral regurgitant jets as signal loss within the flowing blood, which appeared as high signal intensity, bidirectionally in the bileaflet mechanical valve and unidirectionally in the monoleaflet mechanical valve. An abnormal cavity was seen behind the basal left ventricular myocardium in one patient with a CarboMedics valve. The wall of the abnormal cavity was disrupted abruptly and the rest of the wall consisted of pericardium and adjacent tissue in the image taken by the spin echo technique. The image taken by the field echo technique showed an abnormal jet flow from the basal part of the left ventricular cavity into the abnormal cavity, which was compatible with left ventricular pseudoaneurysm. Two-dimensional echocardiography and Doppler color flow mapping disclosed the abnormal cavity and the abnormal flow inside, but failed to show the connection between the left ventricle and the cavity due to reverberation of the ultrasound signal by the prosthetic valve. These findings suggest that MR imaging is a safe and promising method to assess the complications and valvular function in patients with a prosthetic carbon valve in the mitral position.

The effects of nicorandil on coronary collateral circulation during exercise-induced ischemia were compared between the different donor arteries in 13 patients with effort angina, 7 with complete obstruction of the left anterior descending artery (LAD) with well-developed collateral vessels from the right coronary artery (RCA) (LAD group), and 6 with complete occlusion of the RCA (segment 2-3) with well-developed collateral vessels from the LAD (RCA group). Initial percentage thallium (%TI) uptake (thallium-201 single photon emission computed tomography) and washout rate were measured in the anterior, septal and posterior regions during ergometer exercise. The submaximal treadmill exercise test was also performed using a cardiopulmonary monitoring system to measure Vo2 at anaerobic threshold (AT). After the controls were obtained, nicorandil (15 mg/day) was administered for 4 weeks, during which ergometer exercise and treadmill exercise tests were carried out repeatedly. A significant improvement of initial %TI uptake on exercise was observed in the LAD group with nicorandil therapy, but no improvement was shown in the RCA group. The AT significantly increased after nicorandil treatment in the LAD group (13.9 +/- 0.38-->16.8 +/- 1.18 ml/min/kg), reflecting the improvement of cardiac function through the increased collateral flow. However, in the RCA group, it remained unchanged, suggesting no improvement of cardiac function. Nicorandil was effective to increase collateral flow from the RCA, but ineffective on that from the LAD. Nicorandil is an effective coronary dilator and is reported to affect both large and small coronary arteries. The effect on the collateral circulation is dependent on the donor artery supplying different areas. The vasodilator effect of nicorandil is mainly on the LAD, which is large enough to supply blood to a wider area of the heart, rather than the RCA.

The usefulness of low-cost, three-dimensional (3D) images reconstructed from magnetic resonance (MR) imaging for investigating persistent left superior vena cava was assessed and compared to the diagnostic accuracy of chest radiography. MR imaging by the spin-echo technique and MR angiography were performed in 10 patients with this anomaly diagnosed previously by contrast echocardiography and radionuclide angiocardiography. Four patients had complicating cardiac anomalies, one with postoperative atrial septal defect, one with postoperative ventricular septal defect, one with atrial septal defect and partial anomalous pulmonary venous return, and one with aortic coarctation and patent ductus arteriosus. Multisectional and multiphasic MR images were used for the 3D-reconstruction of the cardiovascular and mediastinal structures with a NeXT workstation and a 3D-kit. The 3D-reconstructed MR imaging clearly showed the persistent left superior vena cava and the anatomical relationship with the other cardiovascular and mediastinal structures in all 10 patients. Vascular shadows were observed outside the upper left border of the aortic arch on the chest radiographs in seven patients, and the 3D-reconstructed MR images revealed these shadows to be compatible with superior caval vein. The ratios of the diameter between the left and right superior venae cavae with and without the left innominate vein were 0.63 +/- 0.14 (mean +/- SD) and 0.94 +/- 0.08, respectively. Three-dimensional reconstructed MR imaging is a useful method for recognizing persistent left superior vena cava and precise examination of the chest radiographs often allowed detection of the vascular shadows caused by this anomaly.

This study investigated the clinical significance of abnormally high signal intensity in the left ventricular myocardium on gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) enhanced magnetic resonance (MR) imaging in patients with dilated cardiomyopathy. Gd-DTPA enhanced MR imaging, Tl-201 myocardial single photon emission computed tomography (SPECT), Tc-99m radionuclide angiocardiography, M-mode echocardiography, electrocardiography and chest radiography were performed in 18 patients with dilated cardiomyopathy. The left ventricle was divided into five areas, the anteroseptal, anterolateral, inferoseptal, posterolateral and apical areas. Five patients (group A) had 0-2 and 13 patients (group B) had 3-5 high signal intensity areas. High signal intensity areas were demonstrated in 19 of 90 areas (21%) before Gd-DTPA enhancement and 50 of 90 areas (56%) after enhancement. Fifteen of 34 areas (44%) with abnormal Tl-201 uptake showed high signal intensity before Gd-DTPA enhancement and 31 (91%) showed high signal intensity after enhancement. Fifteen areas without abnormal Tl-201 uptake also showed high signal intensity after enhancement. Left ventricular ejection fraction (LVEF) and percent fractional shortening (%FS) in group B were lower than those in group A. LVEF(r = 0.78) and %FS (r = 0.82) were significantly correlated with the number of high signal intensity areas. Systolic left ventricular dimension was larger in group B than that in group A, and a significant correlation (r = 0.62) between systolic left ventricular dimension and the number of high signal intensity areas was found. There was no significant difference in right ventricular ejection fraction, left ventricular peak filling rate, diastolic left ventricular dimension, left ventricular thickness, cardiothoracic ratio or SV1+RV5 or 6 between group A and B. There was no correlation of peak filling rate, diastolic left ventricular dimension, cardiothoracic ratio or SV1+RV5 or 6 with the number of high signal intensity areas. These results suggest that abnormal high signal intensity on Gd-DTPA enhanced MR imaging may reflect myocardial degeneration, necrosis or fibrosis, and the high signal intensity predicts the severity of left ventricular dysfunction in dilated cardiomyopathy.

Effects of bone morphogenetic protein (BMP)-12 and BMP-13, new members of the BMP family which belong to the transforming growth factor (TGF)-beta superfamily, on terminal differentiation of myoblasts were examined in C2C12 and L-6 myoblasts. When the myoblasts were cultured with BMP-12 or BMP-13, the expression of the myosin heavy chain and the formation of multinucleated myotubes mRNA in L-6 cells. The inhibitory effects of BMP-12 and BMP-13 on myogenic differentiation were similar to the effects of BMP-2, though their potencies were lower than BMP-2. Unlike BMP-2, neither BMP-12 nor BMP-13 induced alkaline phosphatase activity in C2C12 myoblasts. The differences in the biological activities of these new BMPs suggest that the intracellular signalling pathway used by BMP-12 and BMP-13 differs from that of BMP-2.

The rat angiotensin II type 2 receptor (AT2-R) expression was markedly downregulated by the mitogenic action of serum, growth factors and dexamethasone. The regulation by serum or growth factors did not affect the AT2-R mRNA half-life (18 h), whereas the AT2-R half-lives of dexamethasone-treated cells and proliferating cells decreased to 10 h and 15 h, respectively. Nuclear run-off assays indicated the mechanism of repression of AT2-R expression by serum, growth factors and dexamethasone or in proliferating cells to be, in large part, transcriptional. These findings indicate that transcription of the AT2-R gene is regulated in a growth state-dependent manner and suggest that this regulation provides a means by which cells can modulate their responsiveness to the actions of angiotensin II mediated through AT2-R.

Nephrogenic diabetes insipidus (NDI) is a rare X-linked disorder associated with renal tubule resistance to arginine vasopressin (AVP). To understand the mechanisms of AVP resistance underlying this disorder, we have analyzed the vasopressin V2 receptor gene in two unrelated Japanese kindreds with NDI and expressed the mutants to characterize their functional properties. Direct sequencing revealed two V2 receptor gene mutations: a missense mutation from Arg202 to Cys in the third extracellular domain (R202C) and a single base insertion (G) in two consecutive GGG triplets (nucleotide 804 to 809) in the third cytoplasmic domain, resulting in a frame shift with premature termination at codon 258 (804insG). Transient expression study with COS-7 cells showed that R202C mutation reduced both binding affinity (15%) and capacity (30%), while 804insG mutation abolished binding ability. For further evaluation of the binding ability of the R202C mutant, we expressed the mutants in Chinese hamster ovary (CHO) cells. Although the mutant cell lines produced V2 receptor mRNA comparable levels to the wild-type receptor cell lines, R202C mutant cell lines had no binding ability. Our results suggest an introduction of a new cysteine residue in the extracellular domain and a receptor truncation removing one third of the carboxyl terminus could impair ligand binding activity of the V2 receptor through a post-transcriptional mechanism, thereby causing AVP resistance in the NDI patients.

We recently identified vasopressin type 2 receptor gene mutations in two unrelated Japanese families with X-linked nephrogenic diabetes insipidus, which were a missense mutation from Arg143 to Pro (R143P) and a single amino acid deletion of Val278 or 279 (delta V278). To investigate the mechanism by which the mutations cause arginine vasopressin (AVP) resistance in this disorder, we expressed them in mammalian cells and analyzed their functional properties. Stable expression study with Chinese hamster ovary (CHO) cells demonstrated that the R143P mutation reduced receptor binding capacity to 10% of normal. However, the R143P mutant itself had a normal affinity for AVP and stimulated adenylyl cyclase production at up to 50% of the wild-type level, suggesting that the mutant receptors could function normally despite their reduced surface expression. In contrast, the delta V278 mutation totally abolished receptor-ligand binding and subsequent adenylyl cyclase stimulation, indicating that delta V278 mutant is virtually nonfunctional receptor. Northern blotting revealed that mutant CHO cell lines produced levels of receptor mRNA similar to the wild-type cell line. Our results suggest that the two mutations impair binding activity of the receptor without affecting mRNA accumulation, thereby causing AVP resistance through a posttranscriptional mechanism.

The responsiveness of the rat angiotensin II type 1a and type 1b receptor (AT1a-R and AT1b-R) genes to glucocorticoid was examined in rat vascular smooth muscle cells (VSMCs) and the glucocorticoid response element (GRE) of the AT1a-R gene was characterized. Glucocorticoid induced an increase in AT1a-R mRNA levels, whereas AT1b-R mRNA levels were unaffected. The nuclear run-off assay indicated that the transcription of the AT1a-R gene, but not that of the AT1b-R gene, was increased by glucocorticoid. The mRNA stability of AT1a-R was unchanged by glucocorticoid. Promoter/chrolamphenicol acetyltransferase reporter analysis demonstrated that the 5'-flanking region of the AT1a-R gene was functional in rat VSMCs and established that the GRE motif between -770 to -756 could confer glucocorticoid responsiveness on the AT1a-R gene.

The significance of abnormal high signal intensity observed in left ventricular myocardium by gadolinium-diethylenetriaminepenta-acetic acid (Gd-DTPA) enhanced magnetic resonance (MR) imaging in hypertrophic cardiomyopathy (HCM) patients was assessed by comparison with T1-weighted MR imaging, thallium-201 (201Tl) myocardial scintigraphy, radionuclide angiocardiography, M-mode echocardiography, electrocardiography, and chest radiography. The 16 patients were divided into three groups: 8 patients (group I) with abnormal high signal intensity before and after Gd-DTPA enhancement, 4 (group II) with abnormal high signal intensity only after enhancement and 4 (group III) without abnormal high signal intensity. Thallium-201 myocardial single photon emission computed tomography (SPECT) showed 4 of the 8 patients in group I, 3 of the 4 patients in group II and only 1 of the 4 patients in group III had abnormalities of regional 201Tl uptake in the left ventricular myocardium. No significant difference in left ventricular ejection fraction (LVEF) was seen between groups I, II, and III (64 +/- 13%, 67 +/- 17% and 71 +/- 7%, respectively) although three patients of group I had LVEF of less than 55%. Left ventricular peak filling rates (PFR) of groups I and II were significantly lower than that of group III (1.90 +/- 0.44, 2.41 +/- 0.43 and 3.37 +/- 0.48 EDV/sec, respectively). Group I had larger end-diastolic left ventricular dimension (LVDd), significantly larger end-systolic left ventricular dimension (LVDs), and smaller % fractional shortening (%FS) than group III (49 +/- 4 vs 42 +/- 6 mm, 31 +/- 5 vs 22 +/- 4 mm, and 38 +/- 8 vs 49 +/- 4%, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Prolonged survival of the patient with a single ventricle is rare. We report the case of a 57-year-old man who has type A3 of Van Praagh's classification of single ventricle with pulmonary hypertension without pulmonary stenosis. Favorable streaming, a large bulboventricular foramen, and intact atrioventricular valves may have contributed to his long-term survival.

Late potentials have been reported to be affected by body size or left ventricular mass. To our knowledge, however, the effect of subadipose tissue, which is known to influence QRS amplitudes of the surface ECG on the variables of late potentials, has not been evaluated. The relationships between the variables of late potentials and various obesity indices were assessed in 45 men, aged 24 to 38 years, without structural heart disease and bundle branch blocks. QRS duration (DUR), root mean square voltage in the last 40 ms (RMS), and low-amplitude signals < 40 microV (LAS) were obtained by signal-averaged ECG. Left ventricular mass (LV mass) was determined by echocardiography. The DUR and RMS had no correlation with body height, weight, body mass index (BMI), sum of skin folds (triceps and subscapular), or LV mass. Positive linear correlations were found between LAS and weight (r = 0.48, p < 0.002), BMI (r = 0.54, p < 0.002), sum of skin folds (r = 0.57, p < 0.002), and percent BMI (r = 0.54, p < 0.002). Subadipose tissue may shift the onset of the 40-microV point of LAS to the left with a consequent prolongation of LAS by attenuation of the QRS complex. These data suggest that the use of LAS alone or as a combination in an obese population for the definition of positive late potentials is inappropriate.

To evaluate the difference in the process of left ventricular functional recovery after successful percutaneous transluminal coronary angioplasty (PTCA), 25 patients with sudden onset of acute Q wave anterior myocardial infarction (MI [group 1]) and 28 patients with unstable angina prior to MI (group 2) were investigated in the late hospital phase. The circumferential extent of left ventricular dysfunction was significantly larger in group 1 than in group 2. The left ventricular ejection fraction (EF) and the ratio of systemic arterial systolic blood pressure to left ventricular end-systolic volume (P/V ratio) were significantly lower in group 1 compared with group 2. The P/V ratio had nonlinear relationships with left ventricular end-diastolic volume (LVEDV) in both groups and the P/V ratio in group 1 was significantly lower than those in group 2 at any given LVEDV. Thus, in patients with successful PTCA, unstable angina prior to acute MI had better left ventricular pump function in the course of left ventricular remodeling.

Nephrogenic diabetes insipidus (NDI) is a rare X-linked disorder exhibiting renal resistance to the antidiuretic action of arginine vasopressin (AVP). Recent elucidation of the vasopressin V2 (renal type) receptor gene structure has enabled us to test the hypothesis that the genetic defect in the V2 receptor is the likely molecular basis of NDI. By using the polymerase chain reaction (PCR)-direct sequencing, we identified novel V2 receptor gene mutations in two unrelated Japanese kindreds with NDI. In the male patients of kindred A, a single codon deletion in one of two consecutive GTC triplets (nucleotide 832 to 837) was detected. This base change resulted in the loss of a valine residue in the 6th transmembrane domain. In the affected males of kindred B, a G to C substitution was found at nucleotide 428, altering codon 143 from arginine (CGT) to proline (CCT) in the second cytoplasmic domain. PCR-single strand conformation polymorphism (SSCP) analysis of family members demonstrated that the mutations cosegregated with clinically affected individuals and were absent in normal subjects. Our results suggest that different V2 receptor defects could be responsible for AVP resistance in individual NDI kindreds.

To elucidate the incidence and clinical factors related to the occurrence of pericardial effusion in infarction-associated pericarditis, 303 consecutive patients with their first Q-wave anterior myocardial infarction were examined carefully by means of auscultation, echocardiography, chest radiography, and hemodynamic monitoring. During the first 3 days, a pericardial rub was detected in 65 patients and was absent in 238 patients. Among the 65 patients with pericardial rub, pericardial effusion was present in 27 patients (group 1) and was absent in 38 patients (group 2). Although there were no significant differences in cardiac output, pulmonary artery wedge pressure and right atrial pressure between the two groups, patients in group 1 had significantly more left ventricular segments with advanced asynergy and higher radiographic scores (diffuse interstitial infiltrate or alveolar infiltrate) compared with those in group 2. Thus, pericardial effusion and increased extravascular lung water in infarction-associated pericarditis were not caused by left ventricular failure but by other mechanisms reflecting a larger infarct.

To assess the difference in left ventricular performance during exercise between anterior (11 patients) and inferior (10 patients) myocardial infarction (MI) of equivalent size, patients performed a supine bicycle exercise 6 to 8 weeks after the first acute MI. All patients had negative exercise test results and despite no significant differences in HR, blood pressure and stroke volume index at peak exercise, pulmonary artery wedge pressure was significantly higher in anterior (35 +/- 7 mm Hg) than in inferior MI (27 +/- 9 mm Hg). Although there were no significant differences in electromechanical systole (QS2) and diastolic time (DT) at rest, a significant prolongation of QS2 with consequent shortening of DT (p < 0.01) was observed at peak exercise in anterior MI. In addition to decreased subendocardial coronary blood flow from increased left ventricular end-diastolic pressure, a disproportionate shortening of DT in anterior MI may initiate subendocardial ischemia in the noninfarcted segments, which may further impede subendocardial blood flow.

To evaluate the clinical characteristics of patients with anteroseptal myocardial infarction (MI) initially presenting with pulmonary edema, we analyzed 58 patients with anteroseptal MI who underwent emergency coronary arteriography that revealed single-vessel disease of the left anterior descending coronary artery. Of the 58 patients, pulmonary edema was observed in 24 patients (group A) and was absent in 34 patients (group B). Pulmonary capillary wedge pressure was significantly higher, and cardiac output was significantly lower in group A. The site of coronary stenosis, maximum serum creatinine kinase value, and wall motion point score did not differ between the two groups. However, the incidence of previous hypertension and posterior wall thickness > or = 11 mm was significantly higher in group A than in group B (p < 0.001 and p < 0.05, respectively). Thus, impaired left ventricular diastolic filling in the non-MI segments due to higher incidence of hypertension and left ventricular hypertrophy was considered to be the possible cause of pulmonary edema.