Detection and biochemical characterization of circulating proteasomes in dog plasma.

A growing body of evidence convincingly indicates that proteasomes are not located exclusively within cells but also in different extracellular compartments. In humans, in fact, this large multimeric protease has been identified in many body fluids and secretions such as blood, urine, tears, sweat, saliva, milk, and cerebrospinal and pericardial fluid. Intriguingly, the exact origins of these extracellular proteasomes as well as the specific biological functions they perform are largely unknown. As no data on this important subject is yet available in domestic animals, the present study was undertaken to investigate the presence of extracellular proteasomes in canine blood. As a result, for the first time, circulating proteasomes could be clearly detected in the plasma of a cohort of 20 healthy dogs. Furthermore, all three main proteasomal peptidase activities were measured and characterized using fluorogenic peptides and highly specific inhibitors. Finally, the effect of ATP and PA28 family activators on this circulating proteasome was investigated. Collectively, our data indicate that at least a part of the proteasome present in dog plasma consists of a particle that in vitro displays the enzymatic properties of the 20S proteasome.

Extension of the thermal porosimetry method to high gas pressure for nanoporosimetry estimation.

Standard pore size determination methods like mercury porosimetry, nitrogen sorption, microscopy, or X-ray tomography are not suited to highly porous, low density, and thus very fragile materials. For this kind of materials, a method based on thermal characterization has been developed in a previous study. This method has been used with air pressure varying from 10-1 to 105 Pa for materials having a thermal conductivity less than 0.05 W m-1 K-1 at atmospheric pressure. It enables the estimation of pore size distribution between 100 nm and 1 mm. In this paper, we present a new experimental device enabling thermal conductivity measurement under gas pressure up to 106 Pa, enabling the estimation of the volume fraction of pores having a 10 nm diameter. It is also demonstrated that the main thermal conductivity models (parallel, series, Maxwell, Bruggeman, self-consistent) lead to the same estimation of the pore size distribution as the extended parallel model (EPM) presented in this paper and then used to process the experimental data. Three materials with thermal conductivities at atmospheric pressure ranging from 0.014 W m-1 K-1 to 0.04 W m-1 K-1 are studied. The thermal conductivity measurement results obtained with the three materials are presented, and the corresponding pore size distributions between 10 nm and 1 mm are presented and discussed.

Metabolic Profile of Obeticholic Acid and Endogenous Bile Acids in Rats with Decompensated Liver Cirrhosis.

Obeticholic acid (OCA) is a semisynthetic bile acid (BA) analog and potent farnesoid X receptor agonist approved to treat cholestasis. We evaluated the biodistribution and metabolism of OCA administered to carbon tetrachloride-induced cirrhotic rats. This was to ascertain if plasma and hepatic concentrations of OCA are potentially more harmful than those of endogenous BAs. After administration of OCA (30 mg/kg), we used liquid chromatography-mass spectrometry to measure OCA, its metabolites, and BAs at different timepoints in various organs and fluids. Plasma and hepatic concentrations of OCA and BAs were higher in cirrhotic rats than in controls. OCA and endogenous BAs had similar metabolic pathways in cirrhotic rats, although OCA hepatic and intestinal clearance were lower than in controls. BAs' qualitative and quantitative compositions were not modified by a single administration of OCA. In all the matrices studied, OCA concentrations were significantly lower than those of endogenous BAs, potentially much more cytotoxic.

Biochemical and immunomorphological evaluation of hepatocyte growth factor and c-Met pathway in patients with critical limb ischemia.

OBJECTIVES: Hepatocyte growth factor (HGF), the c-Met receptor, and hypoxia-inducible factor (HIF) are crucial for regenerative processes including ischemic wound healing. The aims of the present study are (a) to analyze the tissue c-Met and HIF-1α expression in skin from patients with critical limb ischemia (CLI); (b) to compare the serum HGF levels of CLI and control subjects. METHODS: This is a prospective, controlled, single-center study. Thirty-seven patients were enrolled. A skin sample adjacent to the ischemic lesion was taken from 20 patients with CLI; skin samples were taken from the surgical wounds of 17 patients surgically treated for abdominal aortic aneurysm as healthy controls. Serum samples were taken in all cases. Samples were formalin fixed, paraffin embedded, and routinely processed. Tissue inflammation was histologically assessed. Immunohistochemistry was performed with antibodies against total c-Met receptor, activated Met (p-Met), and HIF-1α. RT-polymerase chain reaction was used to quantify HIF-1α mRNA. The enzyme-linked immunosorbent assay was performed to evaluate serum HGF levels. RESULTS: With immunohistochemistry, while total c-Met was unchanged, different patterns of p-Met positivity were observed between CLI and control cases (p < .001). In particular, CLI skin showed a total negativity or membrane positivity for p-Met (19/20 cases), while control skin mainly showed cytoplasmic positivity in the epidermal basal layer (16/17 cases). HIF-1α was diffusely lost in CLI, but HIF-1α mRNA was threefold higher than in controls. Finally, mean serum HGF levels were 590.5 pg/mL and 2380.0 pg/mL in CLI and control groups respectively (p < .001). CONCLUSIONS: In CLI patients a significant decrease in serum HGF levels, concomitant with a loss of skin HIF-1α stabilization and a lack of c-Met phosphorylation were seen, probably driving a decrease in wound-healing functions. The next hypothesis is that HGF application might reactivate the c-Met receptor, stabilizing the normal wound healing process.

Thermal properties measurement of dry bulk materials with a cylindrical three layers device.

This paper presents a new method dedicated to thermal properties (conductivity and diffusivity) measurement of dry bulk materials including powders. The cylindrical three layers experimental device (brass/bulk material/stainless steel) and the principle of the measurement method based on a crenel thermal excitation are presented. The one-dimensional modeling of the system is used for a sensitivity analysis and to calculate the standard deviation of the estimation error. Experimental measurements are carried out on three bulk materials: glass beads, cork granules, and expanded polystyrene beads. The estimated thermal properties are compared with the values obtained by other measurement methods. Results are in good agreement with theoretical predictions: both thermal conductivity and diffusivity can be estimated with a good accuracy for low density material like cork granules or expanded polystyrene beads since only thermal diffusivity can be estimated for heavier materials like glass beads. It is finally shown that this method like all transient methods is not suited to the thermal characterization of wet bulk materials.

A thermal porosimetry method to estimate pore size distribution in highly porous insulating materials.

Standard pore size determination methods such as mercury porosimetry, nitrogen sorption, microscopy, or x-ray tomography are not always applicable to highly porous, low density, and thus very fragile materials. For this kind of materials, a method based on thermal characterization is proposed. Indeed, the thermal conductivity of a highly porous and insulating medium is significantly dependent on the thermal conductivity of the interstitial gas that depends on both gas pressure and size of the considered pore (Knudsen effect). It is also possible to link the pore size with the thermal conductivity of the medium. Thermal conductivity measurements are realized on specimens placed in an enclosure where the air pressure is successively set to different values varying from 10(-1) to 10(5) Pa. Knowing the global porosity ratio, an effective thermal conductivity model for a two-phase air-solid material based on a combined serial-parallel model is established. Pore size distribution can be identified by minimizing the sum of the quadratic differences between measured values and modeled ones. The results of the estimation process are the volume fractions of the chosen ranges of pore size. In order to validate the method, measurements done on insulating materials are presented. The results are discussed and show that pore size distribution estimated by the proposed method is coherent.

Conducting, semiconducting and insulating objects observed by low-energy electron holography.

To demonstrate the potential of low energy in line projection holography, we study the reconstruction of the experimental holograms of three electrically different objects: a conducting, a semiconducting and an insulating object. The reconstructions of these holograms provide meaningful results for a large range of magnification of the object. The comparison between the reconstructed images and the scanning electron microscopy (SEM) micrographs of the same objects shows that the shapes and the dimensions of the reconstructed objects are identical to those obtained by conventional SEM. So, the simple assumptions needed to the reconstruction are justified. The reconstructions show a 2 nm resolution and appear superior than the best obtained SEM micrographs, when available. We also show some limitations of the reconstruction process. We point out that both numerical artifacts and experimental conditions are responsible for these limitations.

Improved low energy electron projection in-line holograms reconstruction: application to the holograms of a tungsten tip.

A modification of the classical calculation algorithm is presented which allows to minimize the effect of the long range oscillations created by the twin object in the reconstruction process of in-line holograms obtained by low energy electron projection microscopy. The reconstructed shapes of a tungsten tip, observed with different magnifications are shown.

High-yield, in vitro protein expression using a continuous-exchange, coupled transcription/ translation system.

The Rapid Translation System (RTS 500) (Roche Molecular Biochemicals) is a high-yield protein expression system that utilizes an enhanced E. coli lysate for an in vitro transcription/translation reaction. In contrast to conventional transcription/translation, this system allows protein expression to continue for more than 24 h. We demonstrated the utility of the RTS 500 by expressing different soluble and active proteins that generally pose problems in cell-based expression systems. We first expressed GFP-lunasin, a fusion protein that, because of its toxicity, has been impossible to produce in whole cells. The second protein we expressed, human interleukin-2 (IL-2), is generally difficult to produce, either as the native molecule or as a GSTfusion protein, in a soluble form in bacteria. Finally, we demonstrated the capacity of the RTS 500 to co-express proteins, by the simultaneous production of GFP and CAT in a single reaction. This new technology appears to be particularly usefulfor the convenient production of preparative amounts (100-900 microg) of proteins that are toxic or insoluble in cell-based systems.

Imaging charged objects using low-energy-electron coherent beams.

The microscopic shapes, unobservable by conventional electron optics, of objects surrounded by electrostatic fields are observed. The method directly uses electron-coherent-beam imaging concepts and is successfully applied to recently developed low-energy-electron projection holography. Experimental demonstrations on objects charged in a controlled way like a biased metallic tip as well as on a self-charging insulator object are shown.

Validation of a French version of the Dissociative Experiences Scale in a rape-victim population.

OBJECTIVE: To appreciate the extent and the features of dissociation in a hypothesized highly dissociated population, rape trauma victims, while assessing construct validity and internal consistency of a French version of the Dissociative Experiences Scale (DES), a simple screening instrument for dissociative symptoms. METHODS: One hundred and forty rape victims (mean age 23.6 years, 9% male) consecutively attending a Consultation for Victims of Psychological Trauma at the university hospital in Tours, France, were assessed through a French version of the 28-item self-rated DES. RESULTS: The mean score (24.1) was high, and 33% of the scores exceeded a threshold set at 30. The Principal Components Analysis of the DES ratings yielded a 3-factor solution: depersonalization-derealization, amnestic fragmentation of identity, and absorption-imaginative involvement. DES reliability was studied through computation of Cronbach's alpha coefficient (0.94). CONCLUSION: During validation of a French version of the DES, the study showed that dissociation is considerably linked to rape-trauma victim populations.

Similarities and differences between incestuous and nonincestuous rape in a French follow-up study.

Clinicians are familiar with the life and psychological difficulties of incest victims, but their observations often are refuted as being retrospective and unsystematic. We aimed to ascertain similarities and differences between incestuous rape and nonincestuous rape. One hundred and two victims consulting a French forensic center were interviewed in a systematic follow-up study over 6 months using structured interview schedules. Stepwise logistic regression analysis adjusted for age, gender, and characteristics of the trauma showed that posttraumatic stress disorder, dissociative disorders, agoraphobia, and low self-esteem were overrepresented in the incest-rape group compared to the nonincest-rape group.

Screening for psychologically traumatized rape victims.

OBJECTIVE: This study aimed to determine whether the General Health Questionnaire, a simple psychological screening instrument, could be useful to non-specialists in screening for psychologically traumatized rape victims. STUDY DESIGN: 285 rape victims (mean age 22.5, men 8%) attending consecutively a Consultation for Victims of Psychological Trauma at the University Hospital in Tours, France, were assessed through the Structured Interview for Post-Traumatic Stress Disorder (SI-PTSD), and the French 28-item version of the self-rated General Health Questionnaire (GHQ-28). RESULTS: 70% had Post-Traumatic Stress Disorder (PTSD) and 72% a GHQ-28 overthreshold score. The principal component analysis of the GHQ-28 ratings yielded a 4-factor solution: social dysfunction, feeling of foreshortened future type of depression, somatoform complaints and hyperalertness anxiety. GHQ-28 reliability and validity in screening for PTSD were studied through computation of Cronbach's alpha coefficient (0.95), sensitivity (88%) and positive predictive value (86%). CONCCLUSION: Using the GHQ-28 is valid and appropriate for practical use.

Predictive factors of chronic Post-Traumatic Stress Disorder in rape victims.

This study aimed to investigate the psychological disorders following rape as well as the course of Post-Traumatic Stress Disorder (PTSD), and to determine clinical factors predictive of chronic PTSD. Seventy-three rape victims were observed in a systematic follow-up study over 1 year following rape using structured interview schedules. The frequency of PTSD was massive. The early disorders predicting PTSD 1 year after rape included somatoform and dissociative disorders, agoraphobia and specific phobias as well as depressive and gender identity disorders and alcohol abuse. Through stepwise logistic regressions, the following were found to be good models of prediction of chronic PTSD 1 year after rape: for the characteristics of the traumas, intrafamily rape, being physically assaulted outside rape, and added physical violence during rape; for the early psychological and behavioural attitudes, low self-esteem, permanent feelings of emptiness and running away; and for early mental disorders, agoraphobia and depressive disorders. Finally, among all these predictive factors, added physical violence during rape, low self-esteem, permanent feelings of emptiness and agoraphobia were shown to constitute a strong model of predictors. People presenting features such as the predictive factors of chronic PTSD found in the study should be asked about a history of rape and symptoms of PTSD.

[Syndrome secondary to post-traumatic stress disorder and addictive behaviors]. / Syndrome secondaire à un stress traumatique (PTSD) et conduites addictives.

Ninety psychiatric female inpatients had an interview using structural clinical instruments. The patients were often exposed during their lifetime to psychic trauma and especially to sexual abuse in childhood (27%) and rape (21%). Rape is a risk factor for chronicity and severity of mental disorders. Post-traumatic disorders such as PTSD, dissociative disorders, somatoform disorders and borderline-like disorder are linked to rape. Addictive behavior such as alcohol abuse, drugs use, repeated suicide attempts or eating disorders, is also associated with raped patients and especially with those who developed PTSD after rape.

[Psychotic women and their children]. / Les femmes psychotiques et leurs enfants.

With desinstitutionalization, the social life of psychiatric patients and particularly that of psychotics has arisen in new terms over the past twenty years. In particular, relationships and sexuality of these patients are manifest realities to which few studies are devoted. 61 schizophrenic and 21 bipolar women (18-45 years of age, mean 34 in-or outpatients) were interviewed with a battery of instruments (PANSS, Carpenter's criteria of schizophrenia with deficit syndrome, axis V of DSM-III-R) and with a semi-structured questionnaire related to clinical data, sexuality, relationships, children and motherhood. Half of the schizophrenic women have an active sexual life, and children. The study provides information about the reproduction rate of schizophrenic women, the precocity of their pregnancies and the outcome of their children. The study also treats these women's ability to rear their children, their desire to have children and any hospitalizations during the perinatal period. These results, as well as those related to abortion and contraception, are discussed in the light of those of the bipolar control group.

Sexual victimization in women with schizophrenia and bipolar disorder.

Exposure of populations with psychosis to traumatic events (among them sexual trauma) has seldom been studied. In addition, the clinical features developed by victims with psychosis after a traumatic event are rarely taken into account. Sixty-four women with schizophrenia and 26 women with bipolar disorder (DSM-III-R diagnosed, 18-45 years, inpatients and outpatients) were interviewed using a clinician-rated battery of instruments, including a semi-structured questionnaire concerning sexual victimization and its impact. In childhood or adolescence, 36% of women with schizophrenia (vs 28% of those with bipolar disorder) had been victims of sexual abuse involving body contact. In the women with schizophrenia, this sexual abuse was associated with addictions, suicide attempts and becoming psychiatric patients earlier. Over their lifetime, the prevalence of rape was 23% in the two clinical groups. In women with schizophrenia, rape was associated with a greater severity of their disorder and addictions. Moreover, a frequent repetition of sexual trauma was observed in women with schizophrenia, whereas such repeated traumas were less frequent in those with bipolar disorder. The results suggest that these two clinical groups are at risk of rape and the study highlight clinical features in victims with schizophrenia that have been described for other groups of victims of sexual abuse.

[Psychological trauma and mental disorders]. / Les traumatismes psychiques et les troubles mentaux.

Fifty-eight female impatients consecutively hospitalized in the University Hospital Department of Psychiatry in Tours were interviewed with a clinician battery of instruments (among them, the SI-PTSD by Davidson). The diagnoses leading to hospitalization were: severe disorders of psychotic type (schizophrenic, schizophreniform, schizo-affective, schizoid and paranoid delusional disorders as well as bipolar disorder), borderline and narcissistic personalities for 7%, and other disorders for 53%. Among the results, we observed that 59% of these patients had experienced at least one major stressful event (rape 26%, other sexual assault 29%, physical assault 31%, seeing somebody dying in a violent way 8%, war scene 2%, injured in an accident 2%). As a consequence, 61% of the victims have suffered from PTSD and the diagnosis of PTSD was still present in 21%. In addition, in the victims, somatoform and dissociative disorders were significantly more frequent.