Innocuity and immune response to Brucella melitensis Rev.1 vaccine in camels (Camelus dromedarius)

A field trial was conducted in a camel brucellosis-free herd to evaluate antibody response to the Brucella melitensis Rev.1 vaccine in camels and assess shedding of the vaccine strain in milk. Twenty eight camels were divided into four groups according to their age and vaccination route. Groups A (n=3) and B (n=3) consisted of non-pregnant lactating female camels, vaccinated through subcutaneous and conjunctival routes, respectively. Groups C (n=10) consisted of 8-11 months old calves vaccinated through conjunctival route. The rest of the herd (n=12) composed of female and young camels were not vaccinated and were considered as the control group. Each animal from groups A, B and C was given the recommended dose of 2 x 109 colony forming units of Rev.1 vaccine irrespective of age or route of vaccination. Blood samples were collected from all the animals at the time of vaccination and at weekly, bi-weekly and monthly interval until 32 weeks post vaccination and from controls at weeks 8 and 24. The serological tests used were modified Rose Bengal Test, sero-agglutination test, and an indirect Enzyme Linked Immunosorbent Assay. Milk samples were collected from all vaccinated female camels and tested for the presence of Rev.1 vaccine strain. Most vaccinated animals started to show an antibody response at week 2 and remained positive until week 16. By week 20 post-vaccination all animals in the three groups were tested negative for Brucella antibodies. Bacteriological analysis of milk samples did not allow any isolation of Brucella melitensis. All samples were found Brucella negative in PCR analysis. The results of this study indicate that the Rev.1 vaccine induces seroconversion in camels. Rev.1 vaccine strain is not excreted in the milk of camels. These findings are promising as to the safe use of the Rev.1 vaccine in camels.

Isolated cilioretinal artery occlusion as an initial manifestation of polycythemia vera

Isolated cilioretinal artery occlusion is a rarely reported initial manifestation of polycythemia vera. In this study, we reported a case of a 65-year-old man with polycythemia vera with cilioretinal artery occlusion as an initial manifestation.

Analysis of the transverse and the longitudinal pseudodiffusion of CO2 in sub- and supercritical states: a molecular-dynamics analysis

We have performed molecular-dynamics simulations of CO(2) system along the gas-liquid coexistence curve and on the isochore 94.22 cm(3) mol(-1) (which corresponds to the critical isochore). The calculation has been carried out in order to analyze the diffusion of CO(2) and particularly to figure out how the diffusion coefficient may be decomposed along the molecular axes. This makes it possible to analyze the anisotropy of the diffusion along these axes and to shed light on the microscopic changes which accompany such behavior. This anisotropy is traced back to the effect of the translation-rotation coupling (TRC) along the molecular axes. Along the liquid-gas coexistence curve, the pseudolongitudinal diffusion is found to be more rapid than the transverse one. The opposite trend is found along the isochore 94.22 cm(3) mol(-1). The role of the local structure was explored by calculating intermediate scattering function and the autocorrelation functions for the forces acting along the molecular axes. It is shown that the strength of the TRC effect is correlated to the difference between the relaxation times of the local structure, that of the reorientation along the molecular axes, and that of the translational motion. The analysis of the correlation time and the average mean square force along the longitudinal and transverse directions confirms the anisotropy of the local environment that determines the translational dynamics of a molecule.

Analysis of the Effect of Translation−Rotation Coupling on Diffusion along the Molecular Axes

The analysis of the microscopic diffusion processes of CO(2) and H(2)O in the coordinate system defined by the molecular orientation allows a new criterion to be introduced which provides information on the short and long time behavior of the rotation-translation coupling as well as to quantify the strength of this coupling. We discuss the general conditions under which this affects the translation diffusion "seen" by the molecule along its molecular axes. The results show that the translation-rotation coupling is correlated to the local environment in shaping the longitudinal and transversal translation dynamics of a molecule at a microscopic level.

Low-frequency Raman spectra of sub- and supercritical CO2: qualitative analysis of the diffusion coefficient behavior

We report the results of the low-frequency Raman experiments on CO(2) which were carried out in a wide density range, along the liquid-gas coexistence curve in a temperature range of 293-303 K, and on the critical isochore of 94.4 cm(3) mol(-1) in a temperature range of 304-315 K. In our approach, the qualitative behavior of the diffusion coefficient D is predicted, assuming the following: first, that the low-frequency Raman spectra can be interpreted in terms of the translation rotation motions; second, that the random force could be replaced by the total force to calculate the friction coefficient; and finally, that the Einstein frequency is associated with the position of the maximum of the low-frequency Raman spectrum. The results show that the diffusion coefficient increases along the coexistence curve, and its values are almost constant on the critical isochore. The predicted values reproduce qualitatively those obtained by other techniques. The values of D were also calculated by molecular-dynamics simulation and they qualitatively reproduce the behavior of D.

Molecular structure and dynamics of liquids: aqueous urea solutions

In this review a multi-technical approach to the analysis of the structure and dynamics of the urea/water system is described. The reorientational movement of the solute molecule is investigated by the analysis of spectral band-shapes, as well as with the use of the optical Kerr effect (OKE) and molecular dynamics simulation (MDS). The effect of solute concentration on the structure and dynamics of the aqueous solutions (aggregation, orientational distribution, solvation...) is studied by molecular dynamics simulation and neutron scattering. The results obtained by other techniques are included to provide a critical analysis. Finally, the low-frequency Raman spectra of the system are interpreted on the basis of the semi-quantitative information obtained by molecular dynamics simulation.

[Endarteriectomy of the femoral tripod: long-term results and analysis of failure factors]

STUDY AIM

The aim of this retrospective study was to report immediate and long term results of endarteriectomies of the common femoral artery (CFA) and/or femoral tripod and to analyse predictive factors of failure.

PATIENTS AND METHODS

Between 1982 and 1995, 110 endarteriectomies were performed in 101 patients, 52% of them in limb salvage situation. The arteriogram showed a thrombosis or stenosis of the common femoral artery in 100% of cases. There was a stenosis of the deep femoral artery (DFA) in 79% of cases. The superficial femoral artery (SFA) was thrombosed in 40% of cases. One artery only of the lower leg was permeable in 43.3% of cases. Run off was judged bad in 38% of patients.

RESULTS

The endarteriectomy could be realised in 93 patients (84.5%). It concerned the only common femoral artery in 20% of cases (patch angioplasty in 55% of cases), common and deep femoral arteries in 50.5% of cases (82% of patch), CFA, DFA and SFA at its origin in 29.1% of cases (93% of patch). Perioperative mortality rate was 1%. Local morbidity rate was 21.6% with 18% of minor complications and 3.6% of complications requiring a second operation. There were 2% of vascular complications (1 thrombosis and 1 false-aneurysm). Mean follow-up was 43 months in 90 patients. There were restenosis or thrombosis (5.5%), false-aneurysms (2.2%) and amputations (6.6%). Femoro-popliteal (10%) and iliac complementary bypasses (6.6%) were necessary. Permeability was 94.9% at 3 years and 88.8% at 5 years. Clinical results were considered good in 80.7% of the cases at 3 years and in 71.7% at 5 years. With univariate analysis, the predictive factors for failure were: limb salvage (P < 0.01), altered popliteal run off (P < 0.03) and extended distortion of the deep femoral artery (P < 0.05).

CONCLUSION

Isolated endarteriectomy of the femoral tripod is a low risk and effective technique. A femoropopliteal revascularisation should be associated in case of a major alteration of the deep femoral artery.

Rhabdomyosarcome para vertebral : cause rare de compression medullaire

Le rhabdomyosarcome est la tumeur maligne mésenchymateuse la plus fréquente chez l’enfant. Il se voit essentiellement au niveau des extrémités et la sphère ORL. La localisation paravertébrale avec compression médullaire est beaucoup plus rare. Les auteurs rapportent un cas de rhabdomyosarcome paravertébral avec extension endocanalaire et compression médullaire. Il s’agit d’une fille âgée de 6 ans admise pour un tableau de compression médullaire. L’examen clinique retrouve une patiente paraplégique avec niveau sensitif T8, des réflexes ostéo-tendineux abolis et une contracture des muscles paravertébraux. L’IRM médullaire montre un processus tissulaire à point de départ musculaire paravertébral droit, de signal hétérogène avec extension intra-canalaire et compression médullaire. La patiente a eu une laminectomie avec biopsie chirurgicale. L’étude histologique a posé le diagnostic d’un rhabdomyosarcome alvéolaire. La patiente a été traitée par chimiothérapie suivie d’une radiothérapie. L’IRM de contrôle a montré une régression totale du processus tumoral. Après un recul d’une année, la patiente a présenté une récidive locale avec métastases pulmonaires. Malgré cette localisation rare, le rhabdomyosarcome doit être évoqué devant un processus paravertébral avec extension épidurale et compression médullaire chez l’enfant.Mots clés : Rhabdomyosarcome, IRM, compression médullaire.