bluuebunny/crossref_metadata_2025 huggingface dataset:
The M4 Gene of Murine Gammaherpesvirus Modulates Productive and Latent Infection In Vivo
Authors: Townsley A. C. , Dutia B. M. , Nash A. A.
Published: December 2003

Murine gammaherpesvirus 68 (MHV-68) infection of mice represents a viable small-animal model for the study of gammaherpesvirus pathogenesis. MHV-76 is a deletion mutant of MHV-68, which lacks four MHV-68-specific genes (M1 to M4) and eight viral tRNA-like sequences at the 5′ end of the genome. These genes are implicated in latency and/or immune evasion. Consequently, MHV-76 is attenuated in the acute phase of in vivo infection with respect to MHV-68. Little is known about the role of M4 in viral infection, except that it is expressed as an immediate-early/early transcript during lytic replication of MHV-68 in vitro. To elucidate the contribution M4 makes to in vivo pathogenesis, we created a novel MHV-76 mutant (MHV-76inM4), in which the region of MHV-68 coding for M4 and accompanying putative promoter elements were inserted into the 5′ region of the MHV-76 genome. The growth of MHV-76inM4 in vitro was indistinguishable from that of MHV-76 and MHV-68. However, virus titers from MHV-76inM4-infected BALB/c mice were significantly increased with respect to MHV-76 at early times in the lung. In addition, at days 17 and 21 postinfection, there was a significant elevation in latent viral load in splenocytes of MHV-76inM4-infected mice compared to MHV-76. Like MHV-76-infected mice, MHV-76inM4-infected mice display no evidence of overt splenomegaly, a finding characteristic of MHV-68 infection. M4 expression in vivo was detectable during productive infection in the lung and during the establishment of latency in the spleen, but in general M4 was not detectable during long-term latency (day 100 postinfection).
DC-SIGN from African Green Monkeys Is Expressed in Lymph Nodes and Mediates Infection intransof Simian Immunodeficiency Virus SIVagm
Authors: Ploquin Mickaël J.-Y. , Diop Ousmane M. , Sol-Foulon Nathalie , Mortara Lorenzo , Faye Abdourahmane , Soares Marcelo A. , Nerrienet Eric , Le Grand Roger , Van Kooyk Yvette , Amara Ali , Schwartz Olivier , Barré-Sinoussi Françoise , Müller-Trutwin Michaela C.
Published: December 2003

African green monkeys (AGMs) infected by simian immunodeficiency virus (SIV) SIVagm are resistant to AIDS. SIVagm-infected AGMs exhibit levels of viremia similar to those described during pathogenic human immunodeficiency virus type 1 (HIV-1) and SIVmac infections in humans and macaques, respectively, but contain lower viral loads in their lymph nodes. We addressed the potential role of dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN; CD209) in viral dissemination. In previous studies, it has been shown that human DC-SIGN and macaque DC-SIGN allow transmission of HIV and SIVmac to T cells. Here, we looked at the ability of DC-SIGN derived from AGM lymph nodes to interact with SIVagm. We show that DC-SIGN-expressing cells are present mainly in the medulla and often within the cortex and/or paracortex of AGM lymph nodes. We describe the isolation and characterization of at least three isoforms ofdc-signmRNA in lymph nodes of AGMs. The predicted amino acid sequence from the predominant mRNA isoform, DC-SIGNagm1, is 92 and 99% identical to the corresponding human and rhesus macaque DC-SIGN amino acid sequences, respectively. DC-SIGNagm1 is characterized by the lack of the fourth motif in the repeat domain. This deletion was also detected in thedc-signgene derived from thirteen animals belonging to five other African monkey species and from four macaques (Macaca fascicularisandM. mulatta). Despite three- to seven-amino-acid modifications compared to DC-SIGNmac, DC-SIGNagm1 allows transmission of SIVagm to T cells. Furthermore, AGM monocyte-derived dendritic cells (MDDC) expressed at least 100,000 DC-SIGN molecules and were able to transmit SIVagm to T cells. At a low multiplicity of infection (10−550% tissue culture infective doses/cell), viral transmission by AGM MDDC was mainly DC-SIGN dependent. The present study reveals that DC-SIGN from a natural host species of SIV has the ability to act as an efficient attachment and transmission factor for SIVagm and suggests the absence of a direct link between this ability and viral load levels in lymph nodes.
Role of the Ectodomain of the gp41 Transmembrane Envelope Protein of Human Immunodeficiency Virus Type 1 in Late Steps of the Membrane Fusion Process
Authors: Bär Séverine , Alizon Marc
Published: December 2003

The membrane fusion process mediated by the gp41 transmembrane envelope glycoprotein of the human immunodeficiency virus type 1 (HIV-1) was addressed by a flow cytometry assay detecting exchanges of fluorescent membrane probes (DiI and DiO) between cells expressing the HIV-1 envelope proteins (Env) and target cells. Double-fluorescent cells were detected when target cells expressed the type of chemokine receptor, CXCR4 or CCR5, matching the type of gp120 surface envelope protein, X4 or R5, respectively. Background levels of double-fluorescent cells were observed when the gp120-receptor interaction was blocked by AMD3100, a CXCR4 antagonist. The L568A mutation in the N-terminal heptad repeat (HR1) of gp41 resulted in parallel inhibition of the formation of syncytia and double-fluorescent cells, indicating that gp41 had a direct role in the exchange of fluorescent probes. In contrast, three mutations in the loop region of the gp41 ectodomain, located on either side of the Cys-(X)
5
-Cys motif (W596 M and W610A) or at the distal end of HR1 (D589L), had limited or no apparent effect on membrane lipid mixing between Env
+
and target cells, while they blocked formation of syncytia and markedly reduced the exchanges of cytoplasmic fluorescent probes. The loop region could therefore have a direct or indirect role in events occurring after the merging of membranes, such as the formation or dilation of fusion pores. Two types of inhibitors of HIV-1 entry, the gp41-derived peptide T20 and the betulinic acid derivative RPR103611, had limited effects on membrane exchanges at concentrations blocking or markedly reducing syncytium formation. This finding confirmed that T20 can inhibit the late steps of membrane fusion (post-lipid mixing) and brought forth an indirect argument for the role of the gp41 loop region in these steps, as mutations conferring resistance to RPR103611V were mapped in this region (I595S or L602H).
Nuclear Localization of Avian Polyomavirus Structural Protein VP1 Is a Prerequisite for the Formation of Virus-Like Particles
Authors: Johne Reimar , Müller Hermann
Published: December 2003

Virions of polyomaviruses consist of the major structural protein VP1, the minor structural proteins VP2 and VP3, and the viral genome associated with histones. An additional structural protein, VP4, is present in avian polyomavirus (APV) particles. As it had been reported that expression of APV VP1 in insect cells did not result in the formation of virus-like particles (VLP), the prerequisites for particle formation were analyzed. To this end, recombinant influenza viruses were created to (co)express the structural proteins of APV in chicken embryo cells, permissive for APV replication. VP1 expressed individually or coexpressed with VP4 did not result in VLP formation; both proteins (co)localized in the cytoplasm. Transport of VP1, or the VP1-VP4 complex, into the nucleus was facilitated by the coexpression of VP3 and resulted in the formation of VLP. Accordingly, a mutant APV VP1 carrying the N-terminal nuclear localization signal of simian virus 40 VP1 was transported to the nucleus and assembled into VLP. These results support a model of APV capsid assembly in which complexes of the structural proteins VP1, VP3 (or VP2), and VP4, formed within the cytoplasm, are transported to the nucleus using the nuclear localization signal of VP3 (or VP2); there, capsid formation is induced by the nuclear environment.
Characterization of the Inhibition of Hepatitis C Virus RNA Replication by Nonnucleosides
Authors: Tomei Licia , Altamura Sergio , Bartholomew Linda , Bisbocci Monica , Bailey Carolyn , Bosserman Michele , Cellucci Antonella , Forte Eleonora , Incitti Ilario , Orsatti Laura , Koch Uwe , De Francesco Raffaele , Olsen David B. , Carroll Steven S. , Migliaccio Giovanni
Published: December 2003

The RNA-dependent RNA polymerase of hepatitis C virus (HCV) is necessary for the replication of viral RNA and thus represents an attractive target for drug development. Several structural classes of nonnucleoside inhibitors (NNIs) of HCV RNA polymerase have been described, including a promising series of benzothiadiazine compounds that efficiently block replication of HCV subgenomic replicons in tissue culture. In this work we report the selection of replicons resistant to inhibition by the benzothiadiazine class of NNIs. Four different single mutations were identified in separate clones, and all four map to the RNA polymerase gene, validating the polymerase as the antiviral target of inhibition. The mutations (M414T, C451R, G558R, and H95R) render the HCV replicons resistant to inhibition by benzothiadiazines, though the mutant replicons remain sensitive to inhibition by other nucleoside and NNIs of the HCV RNA polymerase. Additionally, cross-resistance studies and synergistic inhibition of the enzyme by combinations of a benzimidazole and a benzothiadiazine indicate the existence of nonoverlapping binding sites for these two structural classes of inhibitors.
Imparting Temperature Sensitivity and Attenuation in Ferrets to A/Puerto Rico/8/34 Influenza Virus by Transferring the Genetic Signature for Temperature Sensitivity from Cold-Adapted A/Ann Arbor/6/60
Authors: Jin Hong , Zhou Helen , Lu Bin , Kemble George
Published: December 2003

The four temperature-sensitive (
ts
) loci identified in the PB1 and PB2 gene segments of cold-adapted A/Ann Arbor/6/60 influenza virus, the master donor virus for influenza A virus (MDV-A) FluMist vaccines, were introduced into a divergent A/Puerto Rico/8/34 influenza virus strain. Recombinant A/Puerto Rico/8/34 virus with these four introduced
ts
loci exhibited both
ts
and
att
phenotypes similar to those of MDV-A, which could be used as a donor virus for manufacturing large quantities of inactivated influenza virus vaccine against potential pandemic strains.
Childhood and adolescence poisoning in NSW, Australia: an analysis of age, sex, geographic, and poison types
Authors: Lam L T
Published: December 2003

Objective:This study aims to investigate whether there is any association between the types of poison substances and geographic locations for different age groups and sex.

Design:This is a population based epidemiological study utilising routinely collected inpatient statistics.

Setting:Data are collected as part of the routine vital health information system via all hospitals in New South Wales (NSW), Australia.

Patients:All patients aged between 0–19 years who were admitted to a hospital because of poisoning by the four major types of substances that were defined in the study in NSW in 2000.

Main results:The standardised incidence ratios of poisoning related hospitalisation between metropolitan and rural areas varied across different poison types when compared with the NSW average. While there are few differences between metropolitan and rural areas for analgesic and chemical related poisoning admissions across different age groups and sex, differences in the standardised incidence ratios between geographic locations for psychotropic and venom related poisoning admissions were found. No significant difference in standardised mortality ratios were found between metropolitan and rural areas except for females in the 10–14 years age group (standardised mortality ratio 3.24, 95% confidence interval 1.69 to 6.21).

Conclusions:The results obtained in this study, on the whole, provide some evidence for an association between poison types and geographic locations for psychotropic and venom related poisoning.
Topography of Low Skin Resistance Points (LSRP) in Rats
Authors: Chiou Sheng-Yuan , Chao Chih-Kai , Yang Ya-Wun
Published: December 2003

Based on the electrical properties of the skin, a method empolying the unijunction transistor (UJT) relaxation oscillator for detecting low skin resistance points (LSRP) was developed in this study. By means of this instrumentation, the topography of the LSRP in Wistar rats was developed. All the LSRP in the rats were found to be bilaterally and symmetrically distributed except those points located on the dorsal midline (i.e., governor vessel, GV) and the ventral midline (i.e., conception vessel, CV). The resistances of the LSRP on these two major vessels, including 14 CV points and 17 GV points of six rats were experimentally determined to be in the ranges of 179.4 ± 41.2 KΩ and 152.5 ± 32.2 KΩ respectively. The resistances of the GV points were found in general to be lower than those of the CV points. Most non-LSRP, on the other hard, exhibited resistances of greater than 420 KΩ. It is noted that the resistances of most LSRP increased yet still retained a separate identity within thirty minutes after the death of the animals, but the low resistance properties of some LSRP gradually disappeared thereafter and could not be detected by the relaxation oscillator.
Gut and Brain Effects of American Ginseng Root on Brainstem Neuronal Activities in Rats
Authors: Yuan Chun-Su , Wu Ji An , Lowell Tasha , Gu Maojian
Published: December 2003

Brainstem neurons receiving subdiaphragmatic vagal inputs were recorded in an in vitro neonatal rat brainstem-gastric preparation. Aqueous extracts of American ginseng root (Panax quinquefolium L.) were applied to the gastric compartment or the brainstem compartment of the bath chamber to evaluate the peripheral gut and central brain effects of the extracts on brainstem unitary activity. After Panax quinquefolium L. application to the gastric or brainstem compartment, a concentration-related inhibition in neuronal discharge frequency in the brainstem unitary activity was observed, suggesting that Panax quinquefolium L. may play an important role in regulating the digestive process and modulating brain function. In this study, pharmacological effects of American-cultivated Panax quinquefolium L. and Chinese-cultivated Panax quinquefolium L. were also compared. Our results suggest that American-cultivated Panax quinquefolium L. possesses a significantly stronger gastric modulating effect on brain neuronal activity.
Inhibitory Effect of Shofu-san, a Japanese Kampo Medicine, on Neutrophil Functionsin vitro
Authors: Akamatsu Hirohiko , Asada Yasuo , Horio Takeshi
Published: December 2003

The effect of Shofu-san (TJ-22), an oral Japanese kampo medicine, on several inflammatory parameters of human neutrophils, including reactive oxygen species (ROS) generation, chemotaxis, and calcium concentration, [Ca2+]i in neutrophils was examined in vitro. In addition, ROS generated in a cell-free, xanthine-xanthine oxidase system was also assessed. The species investigated were superoxide radical anion (02-), hydrogen peroxide (H2O2, and hydroxyl radical (OH•). TJ-22 significantly decreased neutrophil-generated 02-, H2O2and OH• in a dose-dependent manner. The medicine also markedly inhibited neutrophil chemotaxis and [Ca2+]i in neutrophils. In addition, three kinds of ROS generated in the cell-free system was reduced in the presence of TJ-22. Our results indicate that TJ-22 may exert an anti-inflammatory action by inhibiting the neutrophil functions and scavenging ROS, leading to a reduction in oxidative tissue injury.
Prevention of Ethanol-induced Gastric Lesions in Rats by Wu-Bei-San
Authors: Lin Wen-Chuan
Published: December 2003

The effects of Wu-Bei-San (WBS) and its components Wu-Tsi-Ku (WTK) and Bei-Mu (BM) on gastric lesions induced by necrotizing agents were investigated in rats. Oral administration of WBS or WTK, but not BM, dose-dependently prevented gastric lesions induced by ethanol. Moreover, the gastric protective action of WTK was potentiated by simultaneous administration of BM under the same experimental conditions. Pretreatment with indomethacin, which is a prostaglandin synthesis inhibitor and idoacetamide, which is a sulfhydryl blocker did not influence the inhibited ethanol lesion of WBS. Gastric lesions induced by acidified aspirin were prevented by both WBS and calcium carbonate, which is a major constituents of WTK. However, pretreatment with calcium carbonate did not affect the gastric lesions induced by ethanol. These results indicate protective action of WBS on the gastric mucosa through both acid neutralization and cytoprotection, although more work is needed to clarify the role of WBS in cytoprotection.
Effects of Chinese Herbal Prescriptions on Copulatory Activity in Aged Male Rats: A Preliminary Study
Authors: Chang Hui-Chiu , Lue Sheng-l , Hsu Chin , Hsu Hseng-Kuang , Weng Ching-Feng , Yu John Yuh-Lin
Published: December 2003

Four herbal prescription medicines, Chi-Pao-Mei-Jan-Tan, Gui-Fu-Ba-Wei-Wan, Huan-Shao-Tan; and San Tsai-Feng-Sui-Tan, were tested for their effects on sexual behavior in aged rats. Crude liquid extracts of these herbs were administered to the rats daily through oral tubing for 14 days. All four herbal prescriptions showed some effects in restoration of mount and intromission behaviors, but there was no effect on restoration of ejaculation in 26 month old rats that had exhibited no copulatory activity (no mount, intromission and ejaculation) previously. The effects of Chi-Pao-Mei-Jan-Tan were further tested in 26 month old rats with low mount and intromission activities but without ejaculation behavior, and in 15 month old rats (middle-age group) that showed normal mount and intrornission behavior but no ejaculation activity. Chi-Pao-Mei-Jan-Tan was effective in improving the frequency of both mount and intromission, but failed to restore the ejaculation activity of the old rats with low mount and intromission behaviors. It was, however, very effective in restoration of ejaculation activity in middle-aged rats that exhibited normal mount and intromission behaviors. Serum testosterone (T) levels of Chi-Pao-Mei-Jan- Tan in tested old and middle-aged rats were determined by radioimmunoassay, and showed no difference before and after treatment. Our findings demonstrated that the four herbal prescriptions had some effects in restoration of mount and intromission behaviors, but not ejaculation activity in old rats, and that Chi-Pao-Mei-Jan-Tan was very effective in restoration of ejaculation activity in middle-aged rats. The promotional effect of Chi-Pao-Mei-Jan-Tan on copulatory behavior was not correlated with serum T levels.
"Raffinee," a Free Radical Scavenger, in the Treatment of Subacute Stage Brain and Spinal Cord Lesions: A Case Report
Authors: Chen Hsin-Ying , Lin Jer-Min , Lin Chun-Ching
Published: December 2003

This report presents the effects of the natural antioxidant formulation "Raffinee" in treatment of a case with subacute cerebellar hemorrhage and a case with subacute incomplete cervical cord injury. Four days after onset of cerebellar hemorrhage, the regimen started and ameliorated severe headache and dizziness within 3 days. Forty-five days after incomplete spinal cord injury with marked edema of cervical cord, the regimen started. Excellent motor and sensory function recovery were obtained within one month with remission of cord edema. The dosage of "Raffinee" is equivalent to 2,280,000 units of superoxide radical scavenging activity and 47,000 units of hydroxyl radical scavenging activity. Based on the secondary injury theory, superoxide and hydroxyl radical scavengers may have a valuable use in subacute central nervous system (CNS) lesions. Further larger scale of randomized, placebo-controlled, double-blind clinical trials are indicated to verify the effect of "Raffinee" on subacute CNS lesions.
Cordyceps sinensisIncreases the Expression of Major Histocompatibility Complex Class II Antigens on Human Hepatoma Cell Line HA22T/VGH Cells
Authors: Chiu Jen-Hwey , Ju Chien-Hue , Wu Li-Hwa , Lui Wing-Yiu , Wu Chew-Wun , Shiao Ming-Shi , Hong Chuang-Ye
Published: December 2003

Previous studies suggest that down-regulation of the major histocompatibility complex (MHC) antigens on the cell surface of certain tumors results in an escape of immune surveillance. Cordyceps sinensis is well known for its modulatory effect on host immune system. To investigate the modulatory effect of Cordyceps sinensis on MHC class II antigen expression on hepatoma cells, immunostaining with monoclonal antibody (MAb) L243, against the HLA DR region of MHC class II antigens on human hepatoma cell line HA22T/VGH was analyzed by using flow cytofluorimetry. The degree of fluorescence intensity on L243 (+) cells was expressed as relative mean fluorescence intensity (RMFI). The extract of Cordyceps sinensis (VGH-CS-ME-82, 40 μg/ml) was found to increase the MHC class II antigen expression on HA22T/VGH cells with the percentage of L243 (+) cells 40.2 ± 2.5 and RMFI 6.6 ± 0.4; whereas cells without treatment disclosed the percentage of L243 (+) cells 17.2 ± 1.4 and RMFI 5.4 ± 0.3, respectively (p < 0.05). There was a dose-related increase in the degree of fluorescence intensity in terms of RMFI on VGH-CS-ME-82 induced cells. The RMFI in cells treated with IFN-γ0, 0.2 and 5 ng/ml were 5.4 ± 03, 8.2 ± 0.4, and 24.9 ± 1.5, respectively; whereas the RMFI in cells co-incubated with VGH-CS-ME-82 (40 μg/ml) and IFN-γ0, 0.2 ng/:ml and 5 ng/ml were 6.7 ± 0.2 (p <0.05), 9.2 ± 0.9 (p < 0.1) and 29.5 ± 1.2 (p < 0.005), respectively. We conclude that VGH-CS-ME-82, either alone or with IFN-γ induction, increases the MHC class II antigen expression on hepatoma cell line HA22T/VGH, which will shed light into the present immunotherapy, and make the host immune surveillance more effective against tumor cells with down-regulated MHC class II antigen expression.
Medicinal Plants Used for Treating Female Diseases in Malaysia: A Review
Authors: Ling Sui Kiong , Ng Lean Teik
Published: December 2003

A survey of plants used in Malaysia for treating female diseases was made by consulting books, journals and traditional healers. In this report on the survey, forty-four plants are described. Inrormation on plant parts used, methods of preparation and administration, and other usages of plants are given for each species.
Acute Effects of ChunDoSunBup Qi-training on Blood Concentrations of TSH, Calcitonin, PTH and Thyroid Hormones in Elderly Subjects
Authors: Lee Myeong Soo , Kang Chang Won , Shin Yong Sub , Huh Hwa Jeong , Ryu Hoon , Park Jea-Hwang , Chung Hun-Taeg
Published: December 2003

The present study investigated how the systemic treatment of a programmed exercise, ChunDoSunBup (CDSB) Qi-training, affects the secretion of thyroid and parathyroid hormones in elderly subjects (10 male and 5 female). Plasma concentrations of thyroid stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4), parathyroid hormone (PTH), ionized calcium, and calcitonin were determined. CDSB Qi-training induces a slight increase in TSH. Both T4 and T3 were increased at the mid-time of CDSB Qi-training (p < 0.05). There were significant correlations only between T3 and T4 at mid-training. This shows that increase in the plasma level of T3 was associated with the secretion of T4. The plasma concentrations of calcitonin and PTH were increased at mid-time and post-time of CDSB Qi-training. But ionized calcium was decreased slightly by CDSB Qi-training. These results suggest that Qi-training modulates the secretion of thyroid hormones, calcium metabolism, and parathyroid hormones in the elderly. However, whether the long-term practice of CDSB Qi-training might change bone metabolism and have longitudinal effects on the thyroid hormone of the elderly need further investigation.
The Effect of Tert-butyl Hydroperoxide on Peritoneal Macrophages and the Protective Effect of Protein-bound Polysaccharide Administered Intraperitoneally and Orally
Authors: Zhou Mei , Chen Yuan , Ouyang Qian , Liu Shangxi , Pang Zhan-Jun , Wan Jennifer
Published: December 2003

Our previous studies have shown that a protein-bound polysaccharide, polysaccharide krestin (PSK), can protect macrophages from lipoperoxidative injury induced by tert-butyl hydroperoxide (tbOOH) and oxidatively modified low density lipoprotein (O-LDL). PSK was administered intraperitoneally to mice, and the peritoneal macrophages harvested were used as an experimental model. PSK does not reveal any protective effect on macrophages injured by tbOOH when incubated in vitro. In order to elucidate its mode of action, in the present study, the protective effects of PSK were further investigated using morphological changes and viability as indices. It was shown that, compared with the non-PSK group, the viability of macrophages was much higher in the PSK group, and the morphological changes in the PSK group were much less than those in the non-PSK group. The protective effect of PSK administered intraperitoneally and orally on macrophages injured by tbOOH was comparable. Furthermore, the serum of the PSK treated mice had the same protective effect.
Mechanism of the Protective Effects of Sumac Gall Extract and Gallic Acid on the Progression of CCl4-induced Acute Liver Injury in Rats
Authors: Kanai Shigeyuki , Okano Hideyuki
Published: December 2003

To examine the mechanism of the preventive effect of tannins on the progression of carbon tetrachloride (CCl4)-induced acute liver injury in rats, sumac gall (SG) extract and gallic acid (GA) were used as substitutes for crude tannins, because SG is a kind of Chinese traditional medicinal herb containing large amounts of various tannins, and GA is one of the major constituents of SG. The protective effect of oral (p.o.) and intraperitoneal (i.p.) administration of each substance on progression of CCl4-induced hepatitis was investigated in rats. Speculating that the superoxide dismutase (SOD)-like activities (O2 radical-scavenging activities) and/or protective effects of these substances on cell membranes might play a key role in the mechanism opposing the progression of CCl4-induced hepatitis, the O2 radical-scavenging activities in liver cells and serum in rats were monitored. Both substances significantly prevented the progression of acute liver injury with both p.o. and i.p. administration. These findings suggest that the mechanism for this prevention might be due mainly to the protective effect of these substances on cell membranes rather than O2 radical-scavenging activities.
Effect of Pretreatment of Rats with an Urinary Preparation on Liver Injuries Induced by Carbon Tetrachloride and α-Naphthylisothiocyanate
Authors: Lai Tung-Yuan , Wu Yueh-Wern , Lin Jaung-Geng , Lin Wen-Chuan
Published: December 2003

The effect of oral administration of a preparation of human urine (PHU) on the progression of acute liver injury was examined in rats intoxicated with carbon tetrachloride (CCl4) and α-naphthylisothiocyanate (ANIT). PHU protected the liver from CCl4-induced injury as judged by morphological and biochemical observations. In contrast, PHU aggravated ANIT-induced injury as judged also by morphological and biochemical observation. PHU prevented the increase in hepatic glutathione (GSH) and lipid peroxidation induced by CCl4. But PHU enhanced the increase in hepatic GSH caused by ANIT. These results indicate that the effect of PHU on hepatic GSH concentrations is through an indirect pathway. Clinical application of PHU on hepatitis should be explored further.
Involvement of Apoptosis Signal-Regulating Kinase-1 on Angiotensin II-Induced Monocyte Chemoattractant Protein-1 Expression
Authors: Omura Takashi , Yoshiyama Minoru , Kim Shokei , Matsumoto Ryo , Nakamura Yasuhiro , Izumi Yasukatsu , Ichijo Hidenori , Sudo Tatsuhiko , Akioka Kaname , Iwao Hiroshi , Takeuchi Kazuhide , Yoshikawa Junichi
Published: December 2003

Objective—

Monocyte chemoattractant protein 1 (MCP-1) could contribute to enhanced leukocyte recruitment and activation resulting in chronic tissue damage. However, little is known about the molecular mechanisms of cardiac MCP-1 expression. To elucidate these molecular mechanisms, angiotensin II-induced expression of MCP-1 was examined in cultured rat neonatal ventricular cardiomyocytes and fibroblasts by adenovirus gene transfer.

Methods and Results—

MCP-1 mRNA increased 3.6-fold in cardiac fibroblasts at 3 hours after 100 nmol/L angiotensin-II stimulation (
P
<0.01), whereas MCP-1 mRNA in cardiomyocytes was unchanged. Angiotensin II significantly enhanced JNK, p38MAPK, and nuclear factor-κB (NF-κB) activities of cardiac fibroblasts. Wild-type ASK-1 increased MCP-1 expression of cardiac fibroblasts, whereas dominant negative mutant of ASK-1 (DN-ASK), dominant negative mutant of p38MAPK (DN-p38MAPK), and pyrrolidine dithiocarbamate significantly inhibited such expression. The increased MCP-1 mRNA expression in wild-type ASK-1 transfected fibroblasts was inhibited by cotransfection with adenovirus expressing DN-p38MAPK. On the contrary, the decreased MCP-1 mRNA expression in DN-ASK transfected cells was increased by cotransfection with adenovirus expressing constitutively active MKK6.

Conclusion—

Angiotensin II induced MCP-1 gene expression in cardiac fibroblasts. The angiotensin II-induced activation of ASK-1 followed by p38MAPK and NF-κB signaling in cardiac fibroblasts is partially involved in myocardial MCP-1 expression.
Muscle Interstitial Calcium During Head-Up Tilt in Humans
Authors: Samii Soraya , Khan Mazhar H. , MacLean David A. , King Nicholas , Herr Michael D. , Sinoway Lawrence I.
Published: December 2003

Background—

During head-up tilt (HUT), peripheral vasoconstriction occurs. This response requires appropriate communication between the sympathetic nerve terminal and vascular smooth muscle cell in the neurovascular space. Both of these cell types require extracellular calcium ([Ca
2+
]
o
) for proper activation and function. We hypothesize that [Ca
2+
]
o
rises with tilt and in the process contributes to vasoconstriction.

Methods and Results—

We used microdialysis techniques in the lower-limb skeletal muscle to measure [Ca
2+
]
o
changes in this space with HUT. [Ca
2+
]
o
was measured in 10 healthy subjects during HUT. We found a 62% increase in the dialysate [Ca
2+
] (0.223±0.018 to 0.353±0.028 mmol/L) with HUT.

Conclusions—

This result implies a significant increase in [Ca
2+
]
o
in the neurovascular space during HUT. This represents the first report of such in situ [Ca
2+
]
o
measurements in humans. This rise in [Ca
2+
]
o
may provide a mechanism for proper cell-cell interaction, helping to promote peripheral vasoconstriction during HUT. How this [Ca
2+
]
o
transient affects the nerve terminal, vascular smooth muscle cells, or both remains to be determined.
Unrestricted Utilization of Sirolimus-Eluting Stents Compared With Conventional Bare Stent Implantation in the “Real World”
Authors: Lemos Pedro A. , Serruys Patrick W. , van Domburg Ron T. , Saia Francesco , Arampatzis Chourmouzios A. , Hoye Angela , Degertekin Muzaffer , Tanabe Kengo , Daemen Joost , Liu Tommy K.K. , McFadden Eugene , Sianos Georgios , Hofma Sjoerd H. , Smits Pieter C. , van der Giessen Willem J. , de Feyter Pim J.
Published: December 2003

Background—

The effectiveness of sirolimus-eluting stents in unselected patients treated in the daily practice is currently unknown.

Methods and Results—

Sirolimus-eluting stent implantation has been used as the default strategy for all percutaneous procedures in our hospital as part of the
R
apamycin-
E
luting
S
tent
E
valuated
A
t
R
otterdam
C
ardiology
H
ospital (RESEARCH) registry. Consecutive patients with de novo lesions (n=508) treated exclusively with sirolimus-eluting stents (SES group) were compared with 450 patients who received bare stents in the period just before (pre-SES group). Patients in the SES group more frequently had multivessel disease, more type C lesions, received more stents, and had more bifurcation stenting. At 1 year, the cumulative rate of major adverse cardiac events (death, myocardial infarction, or target vessel revascularization) was 9.7% in the SES group and 14.8% in the pre-SES group (hazard ratio [HR], 0.62 [95% CI, 0.44 to 0.89];
P
=0.008). The 1-year risk of clinically driven target vessel revascularization in the SES group and in the pre-SES group was 3.7% versus 10.9%, respectively (HR, 0.35 [95% CI, 0.21 to 0.57];
P
<0.001).

Conclusions—

Unrestricted utilization of sirolimus-eluting stents in the “real world” is safe and effective in reducing both repeat revascularization and major adverse cardiac events at 1 year compared with bare stent implantation.
Adrenomedullin Infusion Attenuates Myocardial Ischemia/Reperfusion Injury Through the Phosphatidylinositol 3-Kinase/Akt-Dependent Pathway
Authors: Okumura Hiroyuki , Nagaya Noritoshi , Itoh Takefumi , Okano Ichiro , Hino Jun , Mori Kenji , Tsukamoto Yoshitane , Ishibashi-Ueda Hatsue , Miwa Senri , Tambara Keiichi , Toyokuni Shinya , Yutani Chikao , Kangawa Kenji
Published: December 2003

Background—

Infusion of adrenomedullin (AM) has beneficial hemodynamic effects in patients with heart failure. However, the effect of AM on myocardial ischemia/reperfusion remains unknown.

Methods and Results—

Male Sprague-Dawley rats were exposed to a 30-minute period of ischemia induced by ligation of the left coronary artery. They were randomized to receive AM, AM plus wortmannin (a phosphatidylinositol 3-kinase [PI3K] inhibitor), or saline for 60 minutes after coronary ligation. Hemodynamics and infarct size were examined 24 hours after reperfusion. Myocardial apoptosis was also examined 6 hours after reperfusion. The effect of AM on Akt phosphorylation in cardiac tissues was examined by Western blotting. Intravenous administration of AM significantly reduced myocardial infarct size (28±4% to 16±1%,
P
<0.01), left ventricular end-diastolic pressure (19±2 to 8±2 mm Hg,
P
<0.05), and myocardial apoptotic death (19±2% to 9±4%,
P
<0.05). Western blot analysis showed that AM infusion accelerated Akt phosphorylation in cardiac tissues and that pretreatment with wortmannin significantly attenuated AM-induced Akt phosphorylation. Moreover, pretreatment with wortmannin abolished the beneficial effects of AM: a reduction of infarct size, a decrease in left ventricular end-diastolic pressure, and inhibition of myocardial apoptosis after ischemia/reperfusion.

Conclusions—

Short-term infusion of AM significantly attenuated myocardial ischemia/reperfusion injury. These cardioprotective effects are attributed mainly to antiapoptotic effects of AM via a PI3K/Akt-dependent pathway.
Impaired Renal Clearance Explains Elevated Troponin T Fragments in Hemodialysis Patients
Authors: Diris Jart H.C. , Hackeng Christian M. , Kooman Jeroen P. , Pinto Yigal M. , Hermens Wim T. , van Dieijen-Visser Marja P.
Published: December 2003

Background—

Patients with severe renal dysfunction often have unexplained elevated serum concentrations of cardiac troponin T (cTnT). We investigated whether in vivo fragmentation of cTnT could explain these increases.

Methods and Results—

cTnT, creatine kinase isoenzyme MB, and myoglobin serum concentrations were measured in all 63 dialysis patients of our in-hospital dialysis department. A highly sensitive immunoprecipitation assay, followed by electrophoresis and Western blotting, was used to extract and concentrate cTnT and its possible fragments from serum of these 63 hemodialysis patients. Although creatine kinase isoenzyme MB values excluded recent ischemic myocardial events in 55 of the 63 cases, cTnT fragments ranging in size from 8 to 25 kDa were present in the serum samples of all dialysis patients.

Conclusions—

cTnT is fragmented into molecules small enough to be cleared by the kidneys of healthy subjects. Impaired renal function causes accumulation of these cTnT fragments and is very likely the cause of the unexplained elevations of serum cTnT found in patients with severe renal failure.
Detection of Calcified and Noncalcified Coronary Atherosclerotic Plaque by Contrast-Enhanced, Submillimeter Multidetector Spiral Computed Tomography
Authors: Achenbach Stephan , Moselewski Fabian , Ropers Dieter , Ferencik Maros , Hoffmann Udo , MacNeill Briain , Pohle Karsten , Baum Ulrich , Anders Katharina , Jang Ik-kyung , Daniel Werner G. , Brady Thomas J.
Published: December 2003

Background—

We investigated the ability of multidetector spiral computed tomography (MDCT) to detect atherosclerotic plaque in nonstenotic coronary arteries.

Methods and Results—

In 22 patients without significant coronary stenoses, contrast-enhanced MDCT (0.75-mm collimation, 420-ms rotation) and intravascular ultrasound (IVUS) of one coronary artery were performed. A total of 83 coronary segments were imaged by IVUS (left main, 19; left anterior descending, 51; left circumflex, 4; right coronary, 9). MDCT data sets were evaluated for the presence and volume of plaque in the coronary artery segments. Results were compared with IVUS in a blinded fashion. For the detection of segments with any plaque, MDCT had a sensitivity of 82% (41 of 50) and specificity of 88% (29 of 33). For calcified plaque, sensitivity was 94% (33 of 36) and specificity 94% (45 of 47). Coronary segments containing noncalcified plaque were detected with a sensitivity of 78% (35 of 45) and specificity of 87% (33 of 38), but presence of exclusively noncalcified plaque was detected with only 53% sensitivity (8 of 15). If analysis was limited to the 41 proximal segments (segments 1, 5, 6, and 11 according to American Heart Association classification), sensitivity and specificity were 92% and 88% for any plaque, 95% and 91% for calcified plaque, and 91% and 89% for noncalcified plaque. MDCT substantially underestimated plaque volume per segment as compared with IVUS (24±35 mm
3
versus 43±60 mm
3
,
P
<0.001).

Conclusions—

The results indicate the potential of MDCT to detect coronary atherosclerotic plaque in patients without significant coronary stenoses. However, further improvements in image quality will be necessary to achieve reliable assessment, especially of noncalcified plaque throughout the coronary tree.
Mediators of Bradykinin-Induced Vasorelaxation in Human Coronary Microarteries
Authors: Batenburg Wendy W. , Garrelds Ingrid M. , van Kats Jorge P. , Saxena Pramod R. , Danser A. H. Jan
Published: December 2003

To investigate the mediators of bradykinin-induced vasorelaxation in human coronary microarteries (HCMAs), HCMAs (diameter ≈300 μm) obtained from 42 heart valve donors (20 men and 22 women; age range, 3 to 65 years; mean age, 46 years) were mounted in Mulvany myographs. In the presence of the cyclooxygenase inhibitor indomethacin, bradykinin relaxed preconstricted HCMAs in a concentration-dependent manner.
N
G
-nitro-
l
-arginine methyl ester and ODQ (inhibitors of nitric oxide [NO] synthase and guanylyl cyclase, respectively) and the NO scavenger hydroxocobalamin, either alone or in combination, shifted the bradykinin concentration-response curve to the right. Removal of H
2
O
2
(with catalase), inhibition of cytochrome P450 epoxygenase (with sulfaphenazole or clotrimazole) or gap junctions (with 18α-glycyrrhetinic acid or carbenoxolone), and blockade of large- (BK
Ca
) and small- (SK
Ca
) conductance Ca
2+
-dependent K
+
channels (with iberiotoxin and apamin), either alone or in addition to hydroxocobalamin, did not affect bradykinin. In contrast, complete blockade of bradykinin-induced relaxation was obtained when we combined the nonselective BK
Ca
and intermediate-conductance (IK
Ca
) Ca
2+
-dependent K
+
channel blocker charybdotoxin and apamin with hydroxocobalamin. Charybdotoxin plus apamin alone were without effect. Inhibition of inwardly rectifying K
+
channels (K
IR
) and Na
+
/K
+
-ATPase (with BaCl
2
and ouabain, respectively) shifted the bradykinin concentration-response curve 10-fold to the right but did not exert an additional effect in the presence of hydroxocobalamin. In conclusion, bradykinin-induced relaxation in HCMAs depends on (1) the activation of guanylyl cyclase, K
IR
, and Na
+
/K
+
-ATPase by NO and (2) IK
Ca
and SK
Ca
channels. The latter are activated by a factor other than NO. This factor is not a cytochrome P450 epoxygenase product or H
2
O
2
, nor does it depend on gap junctions or BK
Ca
channels.
Endothelium-Derived Nitric Oxide Modulates Vascular Action of Aldosterone in Renal Arteriole
Authors: Arima Shuji , Kohagura Kentaro , Xu Hong-Lan , Sugawara Akira , Uruno Akira , Satoh Fumitoshi , Takeuchi Kazuhisa , Ito Sadayoshi
Published: December 2003

We have recently demonstrated that aldosterone causes nongenomic vasoconstriction by activating phospholipase C (PLC) in the preglomerular afferent arteriole (Af-Art). In the present study, we tested the hypothesis that endothelium modulates this vasoconstrictor action by releasing nitric oxide (NO). In addition, to study the post-PLC mechanism, we examined possible contributions of phosphoinositol hydrolysis products. Rabbit Af-Arts were microperfused at 60 mm Hg in vitro, and increasing doses of aldosterone (10
−10
to 10
−8
mol/L) were added to the bath and lumen. Aldosterone caused dose-dependent vasoconstriction (within 10 minutes); significant (
P
<0.01) constriction was observed from 5×10
−9
mol/L, and at 10
−8
mol/L, intraluminal diameter decreased by 29%±3% (n=9). Disrupting the endothelium augmented vasoconstriction; significant constriction was observed from 10
−10
mol/L, and at 10
−8
mol/L, the diameter decreased by 38%±2% (n=6). NO synthesis inhibition reproduced this augmentation (n=7). Pretreatment with chelerythrine (10
−6
mol/L), a protein kinase C (PKC) inhibitor, slightly attenuated the constriction; aldosterone at 10
−8
mol/L now decreased the diameter by 18%±3% (n=7). However, in Af-Arts treated with thapsigargin (10
−6
mol/L) or dantrolene (3×10
−5
mol/L), which blocks inositol 1,4,5-triphosphate (IP
3
)-induced intracellular calcium release, aldosterone at 10
−8
mol/L decreased the diameter by only 9%±1% (n=6) or 9%±2% (n=5), respectively. These results demonstrate that in the Af-Art endothelium-derived NO modulates vasoconstrictor actions of aldosterone that are mediated by the activation of both IP
3
and PKC pathways. Such vasoconstrictor actions of aldosterone may contribute to the development or aggravation of hypertension by elevating renal vascular resistance in cardiovascular diseases associated with endothelium dysfunction.
Role of Caspases in Ox-LDL–Induced Apoptotic Cascade in Human Coronary Artery Endothelial Cells
Authors: Chen Jiawei , Mehta Jawahar L. , Haider Nezam , Zhang Xingjian , Narula Jagat , Li Dayuan
Published: December 2003

Oxidized low-density lipoprotein (ox-LDL) induces apoptosis in endothelial cells. However, steps leading to ox-LDL–induced apoptosis remain unclear. We examined the role of ox-LDL and its newly described receptor LOX-1 in the expression of intracellular pro- and antiapoptotic proteins and caspase pathways in human coronary artery endothelial cells (HCAECs). Cells were cultured and treated with different concentrations (10 to 80 μg/mL) of ox-LDL for different times (2 to 24 hours). Ox-LDL induced apoptosis in HCAECs in a concentration- and time-dependent manner. Ox-LDL also activated caspase-9 and caspase-3, but not caspase-8. After ox-LDL treatment, there was a significant release of activators of caspase-9, including cytochrome
c
and Smac from mitochondria to cytoplasmic compartment, and their release was not affected by treatment of cells with inhibitors of either caspase-8 or caspase-9. Ox-LDL also decreased expression of antiapoptotic proteins Bcl-2 and c-IAP (inhibitory apoptotic protein)-1, which are involved in the release of cytochrome
c
and Smac and activation of caspase-9, in a concentration- and time-dependent manner. On the other hand, ox-LDL did not change the expression of Fas-associated death domain-like interleukin-1β–converting enzyme-inhibitory protein (FLIP) and proapoptotic protein Fas, which are required for the activation of caspase-8. Further, ox-LDL did not cause the truncation of Bid, which implies the activation of caspase-8. In other experiments, pretreatment of HCAECs with the caspase-9 inhibitor z-LEHD-fmk, but not the caspase-8 inhibitor z-IETD-fmk, blocked ox-LDL–induced activation of caspase-3 and apoptosis. As expected, pretreatment with the caspase-3 inhibitor DEVD-CHO inhibited ox-LDL–induced activation of caspase-3 and resultant apoptosis. The proapoptotic effects of ox-LDL were mediated by its receptor LOX-1, because pretreatment of HCAECs with antisense-LOX-1, but not sense-LOX-1, blocked these effects of ox-LDL. These findings suggest that ox-LDL through its receptor LOX-1 decreases the expression of antiapoptotic proteins Bcl-2 and c-IAP-1. This is followed by activation of apoptotic signaling pathway, involving release of cytochrome
c
and Smac and activation of caspase-9 and then caspase-3.
Alternative Strategies for Stroke Care
Authors: Patel Anita , Knapp Martin , Perez Inigo , Evans Andrew , Kalra Lalit
Published: December 2003

Background and Purpose—

Although stroke units reduce mortality and institutionalization, their comparative cost-effectiveness is unknown.

Methods—

Healthcare, social services, and informal care costs were compared for 447 acute stroke patients randomly assigned to stroke unit, stroke team, or domiciliary stroke care. Prospective and retrospective methods were used to identify resource use over 12 months after stroke onset. Cost-effectiveness and cost-utility analyses were undertaken.

Results—

Mean healthcare and social care costs over 12 months were £11 450 for stroke unit, £9527 for stroke team, and £6840 for domiciliary care. More than half the costs were for the initial episode of care. Institutionalization was a large proportion of follow-up costs. Inclusion of informal care increased costs considerably. When informal care was excluded, the incremental cost-effectiveness ratio per percentage point in deaths or institutionalizations avoided in the first year was £496 for the stroke unit over domiciliary care; incremental cost per quality-adjusted life year quality-adjusted life year gained was £64 097 between these 2 groups. The stroke team was dominated by domiciliary care.

Conclusions—

Cost perspectives, especially those related to long-term and informal care, are important when stroke services are evaluated. Improved health outcomes in the stroke unit come at a higher cost.
Transcranial Doppler and Near-Infrared Spectroscopy Can Evaluate the Hemodynamic Effect of Carotid Artery Occlusion
Authors: Vernieri Fabrizio , Tibuzzi Francesco , Pasqualetti Patrizio , Rosato Nicola , Passarelli Francesco , Rossini Paolo Maria , Silvestrini Mauro
Published: December 2003

Background and Purpose—

Cerebral hemodynamic and metabolic changes can compensate for the decrease in cerebral blood flow occurring in patients with carotid occlusive disease. At present, a complete assessment of the cerebral adaptive status is only possible with positron-emission tomography. Near-infrared spectroscopy (NIRS) is a noninvasive technique that, providing a real time assessment of fluctuations in cerebral hemoglobin, has been used to estimate the cerebral blood volume and to measure cerebral vasomotor reactivity (VMR). Moreover, NIRS technology, by allowing the absolute measurement of absorption and scattering coefficients of brain, can determine the oxyhemoglobin and deoxyhemoglobin concentrations in situ in the blood stream.

Methods—

In order to evaluate different aspects of the cerebral hemodynamic status, 27 subjects with symptomatic and asymptomatic carotid artery occlusion and 30 healthy subjects underwent a simultaneous examination by means of transcranial Doppler (TCD), able to reliably detect collateral circulation and VMR, and NIRS at rest condition and during CO
2
reactivity test.

Results—

The main finding of this study was the demonstration of a difference between asymptomatic and symptomatic patients in terms of mean flow velocity increase (52.4% versus 21.0%;
P
<0.001) estimated by TCD and of hemoglobin saturation increase measured by NIRS (6.8% versus 3.8%;
P
=0.015).

Conclusions—

The opportunity to perform NIRS and TCD simultaneously provides useful information about both hemodynamic and metabolic cerebral adaptive status in patients with occlusive disease in a simple, noninvasive, and reliable way.