A higher inherent trait for fearfulness is associated with increased anxiety-like behaviours and diazepam sensitivity in Japanese quail.

This study tested whether lines of Japanese quails divergently selected for a fear response, the tonic immobility, might constitute a reliable bird model for studying anxiety. Previous studies demonstrated that the selection modifies the general underlying emotionality of the birds rather than exerting its effect only on tonic immobility. The behavioural effects of intraperitoneal injections of diazepam, an anxiolytic drug, were assessed in two lines of quail selected either for their short (STI) or long (LTI) duration of tonic immobility. Effects of diazepam were examined in two tests used for measuring emotionality in birds, the open field and the tonic immobility tests. After being placed in the centre of the open field, birds with a high emotionality (LTI quails) stayed longer in the centre of the apparatus than STI quail. Diazepam had anxiolytic effect in LTI birds as it increased the time spent in the outer area. This effect of diazepam appears to be selective because the drug has no effect on other behaviours such as distress calls or escape attempts. The drug has also no effect on the tonic immobility response in any of the two lines. These findings reveal an "anxiogenic" trait of LTI birds in the open field test that can be modulated by the administration of an anxiolytic drug. Therefore quails selected for LTI and STI represent a valuable model to study the mechanisms underlying anxiety in birds.

The robot and the satellite for tele-operating echographic examination in Earth isolated sites, or onboard ISS.

UNLABELLED: The objective was to design and validate a method for tele-operating (from an expert site) an echographic examination in an isolated site. METHOD: The isolated places, defined as areas with reduced medical facilities, could be secondary hospitals 20 to 50 km from the university hospital, or dispensaries in Africa or Amazonia, or a moving structure like a rescue vehicle or the International Space Station (ISS). At the expert center, the ultrasound medical expert moves a fictive probe, connected to a computer (n degrees 1) which sends, the coordinate changes of this probe via an ISDN or satellite line to a second computer (n degrees 2), located at the isolated site, which applies them to the robotic arm holding the real echographic probe. RESULTS: The system was tested at Tours Hospital on 105 patients. A complete investigation (visualization) of all the organs requested for different clinical cases was obtained in 76% of the cases with the robot, and 87% at the reference echography: In 11% of the cases, at least one of the organ visualized at reference echo could not be investigated by the robot, thus the diagnostic was not done. The number of repositioning was higher for the robot (6.5 +/- 2) than for the reference echo (5.1 +/- 2 = or > 24% more with robot). The duration of the examination was higher with the robot (16 +/- 10 min) than for the reference echography (11 +/- 4 min = or > +43% with the robot compare to reference echography. The system was also tested successfully using satellite links in a limited number of cases (approx 30).

Infrequent mutation of the tumour-suppressor gene Smad4 in early-stage colorectal cancer.

Smad4 is a candidate tumour-suppressor gene identified recently on chromosome 18q21.1. Both alleles are inactivated in nearly one-half of pancreatic carcinomas, but its role in the tumorigenesis of other tumours is still unknown. The aim of this study was to investigate the potential involvement of the Smad4 locus in early-stage colorectal cancers (stages I-III) in tumour samples from a randomised multicentre trial. Of a large collection of DNA samples, 73 with a loss of one allele of the Smad4 gene were analysed for the presence of point mutations in the remaining gene. Patients, from whom biopsies were isolated, were part of a previous randomised multicentre study of the Swiss Group for Clinical Cancer Research on the benefit of adjuvant chemotherapy (SAKK study 40/81). Mutation analysis was restricted to the highly conserved C-terminal domain (exons 8, 9, 10 and 11) of Smad4, using PCR and single-strand conformational variant analysis. Two of the 73 patients (3%) with loss of one allele of Smad4 had a point mutation in the remaining allele. These results indicate that whereas Smad4 point mutations are prevalent in pancreatic carcinoma, they are infrequent in early stages (I-III) of colorectal cancer.

SMAD4 is a predictive marker for 5-fluorouracil-based chemotherapy in patients with colorectal cancer.

The gene for the transducer of transforming growth factor-beta/bone morphogenetic protein signalling SMAD4, a potential suppressor of colorectal carcinogenesis, is located at the chromosomal region 18q21. In order to evaluate the clinical relevance of SMAD4 deletion, gene copy alterations were determined by copy dosage using real-time quantitative PCR in 202 colorectal tumour biopsies from a previous randomised study of adjuvant chemotherapy. Patients with normal SMAD4 diploidy turned out to have a three-fold higher benefit of 5-fluorouracil-based adjuvant chemotherapy with a border line significance (overall survival: 3.23, P=0.056; disease-free survival: 2.89, P=0.045). These data are consistent with the previous observation that patients whose cancer had retention of the 18q21 region had a significantly higher benefit from 5-fluorouracil-based therapy. Moreover, these results may provide a refinement at the gene level of the clinical relevance of 18q21 deletion, thereby suggesting SMAD4 as a predictive marker in colorectal cancer. This data also indicate that integrity of this component of the transforming growth factor-beta/bone morphogenetic protein signalling pathway may be a critical factor for benefit of chemotherapy in patients with colorectal cancer.

Venous stagnation induced by 7 days in HDT, in the cerebral, ophthalmic, renal and splanchnic territories.

The scientific objectives was to quantify the vascular changes in the brain, eye fundus, renal parenchyma, and splanchnic network. Heart, portal, jugular, femoral veins were investigate by Echography. The cerebral mesenteric, renal and ophthalmic arteries were investigated by Doppler. Eye fundus vein an papilla were investigated by optical video eye fundus. The left ventricle volume decreased as usual in HDT. The cerebral and ophthalmic vascular resistances didn't change whereas the eye fundus papilla and vein, and the jugular vein increased. These arterial and venous data confirm the existence of cephalic venous blood stasis without sign of intracranial hypertension. On the other hand the kidney volume increased which is in agreement with blood flow stagnation at this level. At last the mesenteric vascular resistance decreased and the portal vein section increased in HDT which is in favor of an increase in flow and flow volume through the splanchnic area.

The DECD box putative ATPase Sub2p is an early mRNA export factor.

Nuclear mRNA metabolism relies on the interplay between transcription, processing, and nuclear export. RNA polymerase II transcripts experience major rearrangements within the nucleus, which include alterations in the structure of the mRNA precursors as well as the addition and perhaps even removal of proteins prior to transport across the nuclear membrane. Such mRNP-remodeling steps are thought to require the activity of RNA helicases/ATPases. One such protein, the DECD box RNA-dependent ATPase Sub2p/UAP56, is involved in both early and late steps of spliceosome assembly. Here, we report a more general function of Saccharomyces cerevisiae Sub2p in mRNA nuclear export. We observe a rapid and dramatic nuclear accumulation of poly(A)(+) RNA in strains carrying mutant alleles of sub2. Strikingly, an intronless transcript, HSP104, also accumulates in nuclei, suggesting that Sub2p function is not restricted to splicing events. The HSP104 transcripts are localized in a single nuclear focus that is suggested to be at or near their site of transcription. Intriguingly, Sub2p shows strong genetic and functional interactions with the RNA polymerase II-associated DNA/DNA:RNA helicase Rad3p as well as the nuclear RNA exosome component Rrp6p, which was independently implicated in the retention of mRNAs at transcription sites. Taken together, our data suggest that Sub2p functions at an early step in the mRNA export process.

Combined copy status of 18q21 genes in colorectal cancer shows frequent retention of SMAD7.

Deletions of chromosome band 18q21 appear with very high frequency in a variety of carcinomas, especially in colorectal cancer. Potent tumor suppressor genes located in this region encode transforming growth factor beta (TGF-beta) signal transducers SMAD2 and SMAD4, and inactivation of either one leads to impaired TGF-beta-mediated cell growth/apoptosis. Following the assignment of SMAD7 to 18q21, we first refined the SMAD7 gene position within this region by genetically mapping SMAD7 between SMAD2 and SMAD4. Further, to compare the respective frequencies of genetic alterations of these three SMAD genes in colorectal cancer, we undertook a large-scale evaluation of the copy status of each of these genes on DNA samples from colorectal tumor biopsy material. Among a subset of 233 DNA samples for which data were available for all four genes, SMAD4, SMAD2, and the nearby gene DCC showed high deletion rates (66%, 64%, and 59%, respectively), whereas SMAD7 was deleted in only 48% of the tumors. Unexpectedly, we found some gene duplications; SMAD7 appears to be more frequently amplified (10%) than the three other genes (4-7%). Compiled data for SMAD genes in each tumor show that the most common combination (26% of all the tumors) consists of the simultaneous deletions of SMAD2 and SMAD4 associated with normal diploidy or even duplication of SMAD7. Since SMAD7 normally counteracts SMAD2 and SMAD4 in TGF-beta signaling, we hypothesize that the tumor might not benefit from simultaneous SMAD7 inactivation, thereby exerting selective pressure to retain or even to duplicate the SMAD7 gene.

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Multiple roles for the yeast SUB2/yUAP56 gene in splicing.

The UAP56 gene has been shown to be required for prespliceosome assembly in mammals. We report here the isolation of the Schizosaccharomyces pombe ortholog of this gene by heterologous complementation of a combined PRP40HA(3)/nam8Delta defect in budding yeast. The Saccharomyces cerevisiae ortholog, YDL084w/SUB2, is also able to suppress this defect. We show that SUB2 is involved in splicing in vivo as well as in vitro. Sub2 defective extracts form a stalled intermediate that contains U2snRNP and can be chased into functional spliceosomes. Our experiments also suggest a role for this protein in events that precede prespliceosome formation. Data reported here as well as in the accompanying papers strongly implicate Sub2p in multiple steps of the spliceosome assembly process.

Overexpression of the alternative oxidase restores senescence and fertility in a long-lived respiration-deficient mutant of Podospora anserina.

Several lines of evidence have implicated reactive oxygen species (ROS) in the pathogenesis of various degenerative diseases and in organismal ageing. Furthermore, it has been shown recently that the alternative pathway respiration present in plants lowers ROS mitochondrial production. An alternative oxidase (AOXp) also occurs in the filamentous fungus Podospora anserina. We show here that overexpression of this oxidase does not decrease ROS production and has no effect on longevity, mitochondrial stability or ageing in this fungus. In the same way, inactivation of the gene has no effect on these parameters. In contrast, overexpression of the alternative oxidase in the long-lived cox5::BLE mutant, deficient in cytochrome c oxidase, considerably increases ROS production of the mutant. It rescues slow growth rate and female sterility, indicating an improved energy level. This overexpression also restores senescence and mitochondrial DNA instability, demonstrating that these parameters are controlled by the energy level and not by the expression level of the alternative oxidase. We also suggest that expression of this oxidase in organisms naturally devoid of it could rescue respiratory defects resulting from cytochrome pathway dysfunctions.

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P21 gene expression as an indicator for the activity of adenovirus-p53 gene therapy in non-small cell lung cancer patients.

Alterations in the tumor suppressor gene p53 lead to impaired cell cycle control, allowing for the development and growth of tumors. To restore a loss of p53 function, we performed a phase I study of intratumoral gene therapy with adenovirus expressing wild-type p53 in patients with non-small cell lung cancer carrying mutations in the p53 gene. Furthermore, in a phase II study, gene therapy was complemented with simultaneous cisplatin/vinorelbine treatment. Biopsies were obtained from all treated patients before and 24-48 hours after gene therapy to study changes in the expression of p53 target genes. We report here that in most of the cases, the target gene p21 was up-regulated, especially when injection of higher doses of p53-expressing adenovirus was combined with simultaneous chemotherapy, whereas Pig3, previously reported to be highly up-regulated by p53, generally did not show a clear increase. Interestingly, a clear p21 gene response was observed only in tumors showing stabilization or regression. We conclude that p21 appears to be up-regulated after adenovirus-mediated p53 gene transfer and is the most sensitive marker tested for biological response to gene therapy in the small cohort of non-small cell lung cancers that were studied.

Idiopathic hyperostosis of the calvaria in five young bullmastiffs.

A new calvarial hyperostotic syndrome (CHS) in young bullmastiffs is described. Calvarial hyperostotic syndrome clinically resembles canine craniomandibular osteopathy (CMO) and human infantile cortical hyperostosis (ICH), but it is unique in that there is progressive and often asymmetric skull bone involvement, and the population affected appears to be only young, male bullmastiff dogs. Characteristic radiographic findings consist of cortical thickening of the calvaria with irregular, bony proliferation over the frontal, temporal, and occipital bones. Histopathological examination shows that the trabeculae of the calvarial diploë are thickened and contiguous with a sunburst-like pattern of subperiosteal trabeculae composed of woven and lamellar bone tissue, accompanied by loose fibrovascular tissue and a variable inflammatory response comprised predominantly of neutrophils. In 80% of the cases presented, the lesion was self-limiting. The etiology remains unknown; however, traumatic, neoplastic, and degenerative conditions do not appear to be primary factors in the etiopathogenesis of the syndrome. It may be that this syndrome has a familial component, similar to that described for CMO and ICH.

Doppler monitoring of the vascular resistance in the lower limbs during dipyridamole test in preparation for myocardial tomoscintigraphy.

OBJECTIVE: the aim of this work was to quantify the intensity of the vasodilation induced by dipyridamole used to simulate a stress test during a myocardial tomoscintigraphy. METHODS: Doppler measurements of the femoral artery and the thoracic aorta were made on 26 patients (11 men, 15 women), using transducers attached to the skin, measurements being performed every 2 min during the 10 min of the stress test. The following parameters were measured: (a) the vascular resistance index of the lower limbs defined as R(fa)=D/S with S and D, respectively, the maximum amplitude of the systolic wave and the maximum amplitude of the diastolic reflux measured on the Doppler femoral spectrogram; (b) the aortic and femoral blood flows obtained from the mean velocity on the Doppler spectrogram. RESULTS: 14 of the 26 patients (54%) showed a significant vasodilation (i.e. a decrease of R(fa) of more than 10%). Eighty-seven percent of the patients with a positive myocardial scintigraphy showed a vasodilation. Sixty-six percent of patients who had prior vasodilator treatment showed no vasodilation. A slight decrease in blood pressure was observed for vasodilated patients but also for non-vasodilated patients. The aortic flow increased slightly for all patients. CONCLUSIONS: Doppler monitoring of femoral vascular resistance is a useful method for quantifying the dipyridamole-induced vasodilation, and hence the stress level upon which the diagnostic efficiency of myocardial scintigraphy is depending. Our study demonstrates that testing with dipyridamole was inconclusive in 66% of patients who had already vasodilator treatment.

A causal link between respiration and senescence in Podospora anserina.

Senescence, a progressive degenerative process leading to age-related increase in mortality, is found in most eukaryotes. However, the molecular events underlying aging remain largely unknown. Understanding how longevity is regulated is a fundamental problem. Here we demonstrate that the respiratory function is a key factor that contributes to shortening lifespan of the filamentous fungus Podospora anserina. In this organism, senescence is systematically associated with mitochondrial DNA instabilities. We show that inactivation of the nuclear COX5 gene encoding subunit V of the cytochrome c oxidase complex leads to the exclusive use of the alternative respiratory pathway and to a decrease in production of reactive oxygen species. This inactivation results in a striking increase of longevity associated with stabilization of the mitochondrial chromosome. Moreover, accumulation of several senescence-specific mitochondrial DNA molecules is prevented in this nuclear mutant. These findings provide direct evidence of a causal link between mitochondrial metabolism and longevity in Podospora anserina.