bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cloning and expression of three aquaporin homologues from the European eel (Anguilla anguilla): effects of seawater acclimation and cortisol treatment on renal expression
Authors: Martinez Anne‐Sophie , Cutler Christopher P. , Wilson Gillian D. , Phillips Claire , Hazon Neil , Cramb Gordon 
Published: July 2005

Background information. The European eel (Anguilla anguilla) is able to osmoregulate over a wide range of environmental salinities from FW (freshwater) to hyperconcentrated SW (seawater). Successful acclimation is associated with strict regulation of ion and water transport pathways within key osmoregulatory epithelia to enable animals to survive the dehydrating or oedematous conditions. These observations suggested that homologues of the AQP (aquaporin) water channel family were expressed in the eel and that these proteins may contribute to the water transport and osmoregulation in all euryhaline teleosts.Results. Complementary DNAs encoding a homologue of the mammalian aquaglyceroporins (termed AQPe) and two homologues of mammalian aquaporin‐1 [termed AQP1 and AQP1dup (aquaporin‐1 duplicate)] were isolated from the European eel. Northern‐blot analysis revealed (i) two AQP1 transcripts exhibiting a wide tissue distribution, (ii) a single AQP1dup mRNA transcript found in the kidney and the oesophagus, and (iii) a single AQPe mRNA detectable mainly in the kidney and the intestine. The relative expression of isoforms within the kidney was AQP1dup>AQPe>AQP1. SW acclimation significantly reduced the abundance of AQP1, AQP1dup and AQPe transcripts in the kidney of yellow eels by approx. 72, 66 and 34$ respectively, whereas the expression levels in silver eels were independent of salinity and equivalent to those observed in yellow SW‐acclimated fish. AQP1 protein expression was primarily located within the vascular endothelium in yellow eels and the epithelial apical brush border in some renal tubules in silver eels. Infusion of cortisol into FW eels had no effect on AQPe mRNA expression, but induced significant decreases in AQP1 and AQP1dup mRNA levels in the kidney of yellow eels. Cortisol infusion had no effect on the expression of any isoform in the silver eels.Conclusions. These results suggest that SW‐acclimation or cortisol infusion induces a down‐regulation of renal AQP expression in yellow eels. However, the lower levels of aquaporin expression found within the silver eel kidney were not further reduced by salinity transfer or steroid infusion. These differences in mRNA expression were accompanied by changes in the cellular distribution of the AQP1 protein between vascular endothelial and tubular epithelial cells.
Expression pattern of the Brachyury and Tbx2 homologues from the sponge Suberites domuncula
Authors: Adell Teresa , Müller Werner E.G. 
Published: July 2005

Background information. T‐box transcription factors are a large family of transcriptional regulators involved in many aspects of embryonic development. In a previous report, we described the isolation and genomic characterization of two T‐box genes from the siliceous sponge Suberites domuncula: a Brachyury homologue, Sd‐Bra, and a Tbx2 homologue, Sd‐Tbx2. Elucidation of the genomic structure of Sd‐Bra allowed us to demonstrate the existence of two different isoforms, resulting from alternative splicing. Moreover, we demonstrated that the shorter isoform exists in two different glycosylation states.Results. In the present study, we demonstrate a differential subcellular localization of the three Sd‐Bra isoforms, suggesting that its differential nuclear import could be an important mechanism for its functional regulation. Furthermore, we demonstrate that Sd‐Tbx2 exists only in one isoform, which is mainly localized in the nucleus. The pattern of expression of Sd‐Bra and Sd‐Tbx2 genes is analysed in sponge tissue, in gemmules and in cultured cells.Conclusion. These results suggest a conserved role for Sd‐Bra in the control of morphogenetic movements through the regulation of cell‐adhesion properties and the involvement of Sd‐Tbx2 in the determination of cell identity in the early stages of differentiation, reminiscent of the function of Tbx2‐3‐4‐5 in vertebrates during limb specification. Also, the fact that a Brachyury and a Tbx2 homologue exist in S. domuncula suggests that the first divergence from the ancestral Brachyury‐like gene might be a Tbx2‐like gene and not a Tbrain‐like gene as had been previously suggested [Adell, Grebenjuk, Wiens and Müller (2003) Dev. Genes Evol. 213, 421–434].
Yeast Ypt11 is targeted to recycling endosomes in mammalian cells
Authors: Kail Mark , Hollinshead Mike , Kaufmann Miriam , Boettcher Jens , Vaux David , Barnekow Angelika 
Published: July 2005

Background information. In yeast, Ypt11 or Ypt32 along with the highly homologous Ypt8 or Ypt31 has been reported to be an essential component of intra‐Golgi trafficking and has been implicated in the budding of vesicles from the most distal Golgi compartment.Results and conclusions. In the present study, we show that, in human cells, after heterologous expression of GFP—Ypt11 (where GFP stands for green fluorescent protein), the protein is targeted to transferrin‐positive recycling endosomes. This compartment has been shown to form extensive tubular networks on applying the drug Brefeldin A. We also show, by confocal fluorescent microscopy, that these networks also contain Rab11 in cells expressing CFP—Rab11a (where CFP stands for cyan fluorescent protein) fusion protein and that these structures are identical with those targeted by GFP—Ypt11.
p38 mitogen‐activated protein kinase (MAPK) first regulates filamentous actin at the 8–16‐cell stage during preimplantation development
Authors: Paliga Andrew J.M. , Natale David R. , Watson Andrew J. 
Published: July 2005

Background information. The MAPK (mitogen‐activated protein kinase) superfamily of proteins consists of four separate signalling cascades: the c‐Jun N‐terminal kinase or stress‐activated protein kinases (JNK/SAPK); the ERKs (extracellular‐signal‐regulated kinases); the ERK5 or big MAPK1; and the p38 MAPK group of protein kinases, all of which are highly conserved. To date, our studies have focused on defining the role of the p38 MAPK pathway during preimplantation development. p38 MAPK regulates actin filament formation through the downstream kinases MAPKAPK2/3 (MAPK‐activated protein kinase 2/3) or MAPKAPK5 [PRAK (p38 regulated/activated kinase)] and subsequently through HSP25/27 (heat‐shock protein 25/27). We recently reported that 2‐cell‐stage murine embryos treated with cytokine‐suppressive anti‐inflammatory drugs (CSAID™; SB203580 and SB220025) display a reversible blockade of development at the 8–16‐cell stage, indicating that p38 (MAPK) activity is required to complete murine preimplantation development. In the present study, we have investigated the stage‐specific action and role of p38 MAPK in regulating filamentous actin during murine preimplantation development.Results. Treatment of 8‐cell‐stage embryos with SB203580 and SB220025 (CSAID™) resulted in a blockade of preimplantation development, loss of rhodamine phalloidin fluorescence, MK‐p (phosphorylated MAPKAPK2/3), HSP‐p (phosphorylated HSP25/27) and a redistribution of α‐catenin immunofluorescence by 12 h of treatment. In contrast, treatment of 2‐ and 4‐cell‐stage embryos with CSAID™ drugs resulted in a loss of MK‐p and HSP‐p, but did not result in a loss of rhodamine phalloidin fluorescence. All these effects of p38 MAPK inhibition were reversed upon removal of the inhibitor, and development resumed in a delayed but normal manner to the blastocyst stage. Treatment of 8‐cell embryos with PD098059 (ERK pathway inhibitor) did not affect development or fluorescence of MK‐p, HSP‐p or rhodamine phalloidin.Conclusion. Murine preimplantation development becomes dependent on p38 MAPK at the 8–16‐cell stage, which corresponds to the stage when p38 MAPK first regulates filamentous actin during early development.
Pulse wave analysis during supine rest may identify subjects with recurrent vasovagal syncope
Authors: Simek Jan , Wichterle Dan , Melenovsky Vojtech , Malik Jan , Svobodova Jaroslava , Svacina Stepan 
Published: July 2005

In the present study, we studied whether analysis of the FAP (finger arterial pressure) waveform during supine rest discriminates subjects with recurrent VVS (vasovagal syncope) from healthy controls. Signal-averaged FAP waveforms (Finapres) were obtained in 32 head-up tilt-test-positive subjects with recurrent VVS (35±13 years) and in 32 sex- and age-matched healthy controls. The DT (time delay) between the systolic and diastolic peaks of the FAP waveform was measured and large artery SI (stiffness index) was calculated as a ratio of body height and DT. VVS patients had significantly shorter DT compared with controls (303±31 compared with 329±18 ms; P&lt;0.001) and higher SI (5.79±0.70 compared with 5.20±0.36 m/s; P&lt;0.001). The differences were independent of heart rate and blood pressure. SI &gt;5.45 m/s identified subjects with syncope with a sensitivity of 72% and a specificity of 84%. Age-corrected DT (cDT=DT+age−350) identified subjects with syncope with a sensitivity of 75% and a specificity of 84%. Combined use of cDT &lt;0 ms and SI &gt;5.45 m/s increased sensitivity and specificity to 81% and 96% respectively. The discriminative power of FAP descriptors improved further when younger subjects were excluded. In subjects aged &gt;30 years (median age), the combination of cDT and SI identified subjects with syncope with a sensitivity of 93% and a specificity of 100%. These results suggest that FAP descriptors during supine rest might be useful in the diagnosis of VVS in middle-aged subjects.
Cardiovascular risk parameters in men with ankylosing spondylitis in comparison with non-inflammatory control subjects: relevance of systemic inflammation
Authors: Divecha Hiren , Sattar Naveed , Rumley Ann , Cherry Lynne , Lowe Gordon D. O. , Sturrock Roger 
Published: July 2005

Men with AS (ankylosing spondylitis) are at elevated risk for CHD (coronary heart disease) but information on risk factors is sparse. We compared a range of conventional and novel risk factors in men with AS in comparison with healthy controls and, in particular, determined the influence of systemic inflammation. Twenty-seven men with confirmed AS and 19 controls matched for age were recruited. None of the men was taking lipid-lowering therapy. Risk factors inclusive of plasma lipids, IL-6 (interleukin-6), CRP (C-reactive protein), vWF (von Willebrand factor), fibrin D-dimer, ICAM-1 (intercellular cell-adhesion molecule-1) and fibrinogen were measured, and blood pressure and BMI (body mass index) were determined by standard techniques. A high proportion (70%) of men with AS were smokers compared with 37% of controls (P=0.024). The AS patients also had a higher BMI. In analyses adjusted for BMI and smoking, men with AS had significantly higher IL-6 and CRP (approx. 9- and 6-fold elevated respectively; P&lt;0.001), fibrinogen (P=0.013) and vWF (P=0.008). Total cholesterol and HDL-C (high-density lipoprotein cholesterol) were lower (P&lt;0.05 and P=0.073 respectively) in AS and thus the ratio was not different. Pulse pressure was also significantly higher in AS (P=0.007). Notably, adjustment for IL-6 and CRP levels rendered all case-control risk factor differences, except pulse pressure, non-significant. In accordance with this finding, IL-6 correlated positively (r=0.74, P&lt;0.001) with fibrinogen, but negatively (r=−0.46, P=0.016) with total cholesterol concentration. In conclusion, men with AS have perturbances in several CHD risk factors, which appear to be driven principally by systemic inflammatory mediators. Inflammation-driven atherogenesis potentially contributes to the excess CHD risk in AS.
Increased uterine arterial pressure and contractility of perfused swine uterus after treatment with serum from pre-eclamptic women and endothelin-1
Authors: Maltaris Theodoros , Scalera Fortunato , Schlembach Dietmar , Hoffmann Inge , Mueller Andreas , Binder Helge , Goecke Tamme , Hothorn Torsten , Schild Ralf L. , Beckmann Matthias W. , Dittrich Ralf 
Published: July 2005

The present study was designed to examine the effects of ET-1 (endothelin-1) and serum from PE (pre-eclamptic), HP (healthy pregnant) and HNP (healthy non-pregnant) women on uterine arterial perfusion pressure and uterine contractility. Swine uteri (n=25) were perfused for a period of up to 11 h, with the aim being to preserve a viable organ. Various concentrations of ET-1 as well as serum from PE, HP and HNP women (n=10 per group) were administered to the perfused swine uteri and IUP (intrauterine pressure) and IAP (intra-arterial pressure) were recorded. ET-1 produced dose-dependent increases in IUP and IAP. The ET-1 concentration in serum was higher in serum from PE women than in HP and HNP women (P&gt;0.05). Administration of all serum samples had a contractile effect on the swine uterus, with the greatest effect being seen in HNP women (12.8±5.3 mmHg), followed by PE (9.06±4.2 mmHg) and HP (6.1±4.1 mmHg) women. Statistically significant differences were observed between HNP and PE women (P=0.048), and PE and HP women (P=0.021). Increases in IAP following administration of serum from PE women (48.8±20.0 mmHg) were significantly higher (P=0.024) compared with the effect of serum from HP women (28.4±13.7 mmHg). In conclusion, the findings show that serum from PE women has significant vasoconstrictive and oxytocic effects compared with serum from HP women. In pre-eclampsia, the balance between vasorelaxing and vasoactive substances is disturbed.
ATP-binding cassette transporter G8 M429V polymorphism as a novel genetic marker of higher cholesterol absorption in hypercholesterolaemic Japanese subjects
Authors: Miwa Kenji , Inazu Akihiro , Kobayashi Junji , Higashikata Toshinori , Nohara Atsushi , Kawashiri Masaaki , Katsuda Shoji , Takata Mutsuko , Koizumi Junji , Mabuchi Hiroshi 
Published: July 2005

The ratio of serum plant sterols to cholesterol is positively correlated with the fractional cholesterol absorption, whereas serum precursors of cholesterol synthesis are positively correlated with cholesterol synthesis. Recently, two ABC (ATP-binding cassette) transporters, ABCG5 and ABCG8, have been described as playing an important role in the absorption and excretion of sterols. In the present study, we tested the hypothesis that genetic variation in ABCG5/ABCG8 influences the levels of serum plant sterol (sitosterol) and cholesterol precursor (lathosterol) in Japanese primary hypercholesterolaemic patients (n=100). We identified a novel mutation [859T/C (C287R)] and a novel polymorphism [1285A/G (M429V)] at the ABCG5/ABCG8 loci, as well as four polymorphisms reported previously [1810C/G (Q604E), 161G/A (C54Y), 1199C/A (T400K) and 1895C/T (A632V)]. In carriers of the novel M429V variant, the serum level of sitosterol and the sitosterol/cholesterol ratio were significantly higher than those in non-carriers (3.64 compared with 2.56 μg/ml, and 1.45 μg/mg compared with 1.00 μg/mg respectively; P&lt;0.01 for both), and serum lathosterol tended to be lower (1.95 μg/ml compared with 3.03 μg/ml; P=0.08), whereas no significant difference was observed in other lipid profiles. These four polymorphisms (1810C/G, 161G/A, 1199C/A and 1285A/G) generated six haplotypes, and the C/G/C/G haplotype was significantly associated with a higher sitosterol level and sitosterol/cholesterol ratio compared with the other five haplotypes (P&lt;0.05 for both). We conclude that, in 8% of patients with hypercholesterolaemia, the novel ABCG8 M429V variant was associated with higher cholesterol absorption efficiency. Future studies should investigate whether these findings have implications for the optimal cholesterol-lowering drug treatment in hypercholesterolaemic patients.
Changes in the expression of genes related to bile acid synthesis and transport by the rat liver during hepatocarcinogenesis
Authors: Monte Maria J. , Fernandez-Tagarro Maria , Macias Rocio I. R. , Jimenez Felipe , Gonzalez-San Martin Francisco , Marin Jose J. G. 
Published: July 2005

The relationship between BA (bile acid) secretion (measured by GC–MS) and the expression of genes (measured by reverse transcription real-time PCR) involved in liver BA transport and metabolism was investigated at 20 and 32 weeks during rat hepatocarcinogenesis. A progressive loss of mRNA for transporters (more marked for Ntcp, Bsep and Mrp2 than for Oatp1/Oatp1a1, Oatp2/Oatp1a4 and Oatp4/Oatp1b2) was found. The mRNA levels of Cyp7a1 and the nuclear receptors FXR (farnesoid X receptor), SHP (small heterodimer partner) and FTF (α-fetoprotein transcription factor) were not modified, whereas those of Cyp8b1 were enhanced and those of Cyp27 were reduced. Biliary secretion of CA (cholic acid) remained unchanged, whereas that of CDCA (chenodeoxycholic acid) and other non-C12-hydroxylated BAs was diminished. The re-appearance of ‘flat-BAs’ (mainly allo-BAs at 20 weeks and Δ4-unsaturated-BAs at 32 weeks) probably reflects the progressive decrease observed in the expression of 3-oxo-Δ4-steroid 5β-reductase, together with the maintenance of steroid 5α-reductase type I. A significant correlation between the 5α-reductase/5β-reductase ratio and bile output of ‘flat-BAs’ was found. In conclusion, during rat hepatocarcinogenesis, the expression of transporters/enzymes responsible for BA homoeostasis is changed due to mechanisms other than those controlled by FXR/SHP/FTF. These modifications result in the re-appearance of ‘flat-BAs’, together with an increased CA/CDCA ratio in bile.
Effects of Systemic and Local CXC Chemokine Administration on the Ethanol‐Induced Suppression of Pulmonary Neutrophil Recruitment
Authors: Quinton Lee J. , Nelson Steve , Zhang Ping , Happel Kyle I. , Gamble Lisa , Bagby Gregory J. 
Published: July 2005

Background:Acute alcohol intoxication impairs the neutrophil response to intrapulmonary infection, resulting in impaired host defense and increased patient morbidity and mortality. We recently showed that intratracheal (IT) chemokine administration promotes pulmonary neutrophil migration in rats and that this process is enhanced by systemic administration of the Glu‐Leu‐Arg (ELR+) and CXC chemokine cytokine‐induced neutrophil chemoattractant (CINC). Here we hypothesized that exogenous chemokine administration would mitigate the suppressive effect of alcohol on neutrophil recruitment into the lung.Methods:Macrophage inflammatory protein‐2 (MIP‐2), a rat ELR+ CXC chemokine, or live Klebsiella pneumoniae (K. pneumoniae) was administered it to induce alveolar neutrophil migration in the absence or presence of acute ethanol intoxication. Depending on the experimental protocol, rats received either intravenous (IV) CINC or IT chemokines (CINC and MIP‐2) 20 min after it MIP‐2 or K. pneumoniae. Rats were euthanized 90 min or four hr after the first IT injection for sample collection.Results:Neutrophil counts were significantly elevated in bronchoalveolar lavage fluid (BALF) of rats receiving IT MIP‐2 compared with vehicle‐treated rats, and this response was significantly decreased in animals pretreated with ethanol. CINC IV enhanced the neutrophil response to IT MIP‐2 in both the absence and presence of acute ethanol intoxication. In rats challenged with K. pneumoniae, ethanol pretreatment significantly reduced BALF levels of CINC and MIP‐2, suppressed alveolar neutrophil recruitment, and decreased whole‐lung myeloperoxidase activity. CINC IV did not alter BALF neutrophil counts in the absence or presence of ethanol administration 4 hr after IT K. pneumoniae. Alternatively, IT chemokine instillation partially restored BALF neutrophil recruitment but not whole‐lung myeloperoxidase activity in ethanol‐treated rats.Conclusions:Ethanol significantly inhibits the pulmonary inflammatory responses to both MIP‐2 and K. pneumoniae. Exogenous chemokine administration may be a useful means to enhance host defenses in the ethanol‐intoxicated host, although the results of this study also indicate that ethanol intoxication can impair neutrophil recruitment, independent of its effects on local chemotactic gradients.
Influence of Age at Drinking Onset on Long‐Term Ethanol Self‐Administration With Deprivation and Stress Phases
Authors: Siegmund Sören , Vengeliene Valentina , Singer Manfred V. , Spanagel Rainer 
Published: July 2005

Background:Onset of alcohol use during adolescence has potentially long‐lasting consequences, e.g., prospective alcohol dependence. To obtain new insight into the effects of early chronic ethanol consumption, we compared the drinking behavior of two adult male Wistar rat groups: one that initiated alcohol consumption during adolescence (adolescent group) and the other that initiated their drinking during adulthood (adult group) in a model of long‐term alcohol self‐administration. We investigated the magnitude of the effects of deprivation and stress on alcohol intake and the influence of these events on the alcohol drinking behavior across time.Methods:Heterogeneous Wistar rats aged 31 days (adolescents) and 71 days (adults) were given ad libitum access to water, as well as 5% and 20% ethanol solutions during an observation period of 30 wk. A deprivation phase of 14 days was instituted after eight wk of access to alcohol. After 16 and 26 wk of alcohol access, all animals were subjected for three consecutive days to forced swimming and electric foot shocks, respectively.Results:At the onset of drinking, adolescent animals consumed less alcohol and showed lower preference than adults. The deprivation phase was followed by increased intake of highly concentrated ethanol solution without appreciable differences between age groups. Repeated swim stress produced a slight increase in ethanol consumption in both animal groups; however, alcohol intake was not significantly different between groups, whereas the foot shock stress‐induced increase in alcohol intake was significantly higher in the animal group that initiated alcohol consumption during adolescence. After swim stress, the drinking behavior of the adolescent group resembled that of the adult group. In particular, the adolescent group increased their preference for 20% ethanol solution for the remainder of the experiment.Conclusions:Age of voluntary alcohol drinking onset does not appear to be a strong predictor for prospective alcohol intake and relapse‐like drinking behavior under the present experimental conditions. However, male Wistar rats that initiated alcohol consumption during adolescence seem to be more susceptible to acute stressor‐specific effects in terms of alcohol consumption.