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Ab initio calculations of the melting curve of molybdenum for the pressure range 0-400 GPa are reported. The calculations employ density functional theory (DFT) with the Perdew-Burke-Ernzerhof exchange-correlation functional in the projector augmented wave (PAW) implementation. Tests are presented showing that these techniques accurately reproduce experimental data on low-temperature body-centered cubic (bcc) Mo, and that PAW agrees closely with results from the full-potential linearized augmented plane-wave implementation. The work attempts to overcome the uncertainties inherent in earlier DFT calculations of the melting curve of Mo, by using the "reference coexistence" technique to determine the melting curve. In this technique, an empirical reference model (here, the embedded-atom model) is accurately fitted to DFT molecular dynamics data on the liquid and the high-temperature solid, the melting curve of the reference model is determined by simulations of coexisting solid and liquid, and the ab initio melting curve is obtained by applying free-energy corrections. The calculated melting curve agrees well with experiment at ambient pressure and is consistent with shock data at high pressure, but does not agree with the high-pressure melting curve deduced from static compression experiments. Calculated results for the radial distribution function show that the short-range atomic order of the liquid is very similar to that of the high-T solid, with a slight decrease of coordination number on passing from solid to liquid. The electronic densities of states in the two phases show only small differences. The results do not support a recent theory according to which very low dT(m)dP values are expected for bcc transition metals because of electron redistribution between s-p and d states.

Q fever is a worldwide-occurring zoonosis caused by Coxiella burnetii. Better knowledge of the disease and of evolving diagnostics can enable recognition of unusual manifestations. Reported here are four cases of Q fever osteoarticular infections in adults: two cases of Q fever tenosynovitis, which represent the first two reports of this infection, and two cases of Q fever spondylodiscitis complicated by paravertebral abscess. In addition, the literature is reviewed on the 15 previously reported cases of Q fever osteoarticular infection, six of which were vertebral infections. Osteomyelitis is the usual manifestation Q fever osteoarticular infection. Because its onset is frequently insidious, diagnosis is usually delayed. The main differential diagnosis is mycobacterial infection, based on the histological granulomatous presentation of lesions. Whereas serology is the reference diagnostic method for Q fever, detection of C. burnetii in tissue specimens by PCR and cell culture provides useful additional evidence of infection. Culture-negative osteoarticular samples with granulomatous presentation upon histological examination should raise suspicion of Q fever.

Objective: To analyze patients' assessment of quality of care in our intensive care unit., Method: We sent questionnaires to the homes of all patients admitted to intensive care from November 2002 through August 2003 who received mechanical ventilation for more than 24 hours., Results: In all, we received 70 analyzable questionnaires. Patients' average age was 56.3 years and the mean duration of stay 13.6 days. Pain was mentioned by 47% of patients and was associated, in decreasing order of frequency, with endotracheal suctioning, placement of a urinary catheter, venipuncture, movement into a different position by staff and arterial punctures. Pain intensity evaluated by an analogic visual scale classified these procedures in the following order: endotracheal suctioning, urinary catheterization, position changing by staff, arterial punctures, venipunctures. 54% of the patients remembered mechanical ventilation. Overall, 17% reported feeling fear often or continuously. Aspects of the ICU environment that bothered them were, in order of decreasing frequency, communication difficulties, thirst, lack of sleep, staff discussions at the patient's bedside, noise and light. Finally, 34% no longer remembered the reason for their stay in the ICU and 19% reported they would have liked to be allowed more frequent visits from their relatives., Conclusion: Nearly half of the respondents underwent painful procedures, primarily endotracheal suctioning. One third did not know why they had been in the ICU. To improve the quality of intensive care, it is essential to make the nursing and medical teams aware of these findings.

Summary: : The proportion of non-B HIV-1 variants is increasing in Western Europe. The impact of the high polymorphism in the protease and reverse transcriptase genes, as recently described for CRF02-AG isolates of African origin, on antiretroviral resistance is still disputed. We first examined the polymorphism of these genes in CRF02-AG strains recovered from drug-naive patients followed at the University Hospital of Saint-Etienne in France, most of these of French origin and harboring a clonal strain as elicited by phylogenic analysis. The first plasma sample detected positive from 31 CRF02-AG and 23 B strains was used to compare sequences with their respective subtype consensus strain. The overall number of mutations was dramatically higher for CRF02-AG strains than for B strains in both protease and reverse transcriptase genes (P < 0.0001 and 0.009, respectively). In addition, no statistically significant difference in the number of therapeutic failures, mean CD4 cell count, and viral load was observed between 22 and 45 patients infected with CRF02-AG or B strains, respectively, during a mean treatment period of 25.5 months. Even if no striking antiretroviral failure linked to this polymorphism was observed during short-term follow-up, its impact on long-term therapy will have to be extensively evaluated in patients infected by non-B HIV-1 variants.

The cases of 52 patients with Propionibacterium acnes infection of orthopaedic implants are summarized: 20 patients with definite infection (sepsis, with P. acnes recovered from multiple specimens per patient), 15 with probable infection (sepsis, with P. acnes recovered from one specimen), and 17 with possible infection (signs of prosthetic malfunction or pseudo-osteoarthritis, with P. acnes recovered from one specimen). The patient population consisted of 37 males and 15 females with a mean age of 51.8 years (range 17-88). Besides bone surgery, 21% of these patients had severe coexisting illness. The study population was very heterogeneous and clinical presentation very polymorphic; infections became clinically apparent through sepsis, prosthetic malfunction, or a delay in consolidation. The diagnosis was highly dependent on the quality of the samples taken and the methodology used by the microbiology laboratory to isolate this bacterium. Culture time was long, on average 11.4 days. Treatment involved a combination of antibiotic treatments (67% of cases) and ablation of the material (83% of cases). Although P. acnes is considered to be weakly pathogenic, this bacterium may be responsible for infections in patients with implanted orthopaedic material. Ablation of the arthroplastic or osteosynthetic material is necessary in the majority of cases.

A diffusion Monte Carlo simulation of superfluid 4He at zero temperature and pressures up to 275 bar is presented. Increasing the pressure beyond freezing (approximately 25 bar), the liquid enters the overpressurized phase in a metastable state. In this regime, we report results of the equation of state and the pressure dependence of the static structure factor, the condensate fraction, and the excited-state energy corresponding to the roton. Along this large pressure range, both the condensate fraction and the roton energy decrease but do not become zero. The roton energies obtained are compared with recent experimental data in the overpressurized regime.

Objective: The authors had for aim to study the distribution of HIV-1 subtypes in a cohort of HIV-1 positive patients in the University hospital of Saint-Etienne, France, and to describe the epidemiological characteristics of patients infected with a non-B subtype strain., Design: An epidemiological study was made on 271 HIV-1 positive patients followed up in the Infectious Diseases Department over 20 years. All patients sample were subtyped by serotyping and some samples were also tested by genotyping., Results: Two hundred and sixty-four patients (191 men and 73 women) were found infected by an HIV-1 strain belonging to the M group. After combining serotyping and genotyping results, 195 patients were found infected by a B subtype and 69 by a non-B subtype. Most of the latter strains belonged to an A subtype or related ones. The following factors were shown to be linked to an infection by a non-B strain: being born abroad, having contracted the infection though heterosexual practice, and being a woman. The incidence of non-B strains increased regularly over time (to reach more than 40% in 2003). This progression was especially noted for men born in France with risky sexual behaviour., Conclusion: These results indicate that more than 40% of HIV-1 new cases detected in the Saint-Etienne area are related to non-B strains and that strains of A and related subtypes are common in the local population with risky sexual behaviour.

Between January 2002 and July 2003, 173 bronchoalveolar lavage (BAL) specimens from 150 patients (19 HIV-infected and 131 non-HIV-infected patients) were evaluated for identification of Pneumocystis jiroveci (formerly known as Pneumocystis carinii f. sp. hominis) using staining techniques, conventional PCR (mtLSUrRNA gene) and real-time PCR (MSG gene). Test results were compared to Pneumocystis pneumonia (PCP) confirmed by typical clinical findings and response to treatment. Sensitivity and specificity of the techniques were 60 and 100% for staining (where either one or both techniques were positive), 100 and 87.0% for conventional PCR and 100 and 84.9 % for real-time PCR, respectively. The use of a concentration of 10(3) copies of DNA per capillary of BAL as a cut-off (determined by real-time PCR) increased specificity from 84.9 to 98.6% without reducing the sensitivity of the technique. This technique is rapid (<3 h) and therefore of major interest in differentiating between asymptomatic carriage and PCP. A BAL specimen with <10(3) copies per capillary of Pneumocystis-specific DNA is more likely to indicate a chronic carrier state, but in such cases follow-up is required to ensure that the patient is not in the early stage of an active PCP.

Unseparated peripheral blood mononuclear cells (PBMCs) obtained from drug-naïve African individuals living in a context of multi-infections and presenting with high viral load (VL), were cultured in vitro and tested for their ability to produce antibodies (Abs) reacting with HIV-1 antigens. Within these PBMCs, circulating B cells were differentiated in vitro and produced IgG Abs against not only ENV, but also GAG and POL proteins. Under similar experimental conditions, HAART treated patients produced Abs to ENV proteins only. The in vitro antibody production by drug-naïve individuals' PBMCs depended on exogenous cytokines (IL-2 and IL-10) but neither on the re-stimulation of reactive cells in cultures by purified HIV-1-gp160 antigen nor on the re-engagement of CD40 surface molecules. Further, it was not abrogated by the addition of various monoclonal Abs (mAbs) to co-stimulatory molecules. This suggests that the in vitro antibody production by drug-naïve individuals' PBMCs resulted from the maturation of already envelope and core antigen-primed, differentiated B cells, presumably pre-plasma cells, which are not known to circulate at homeostasy. As in vitro produced Abs retained the capacity of binding antigen and forming complexes, this study provides pre-clinical support for functional humoral responses despite major HIV- and other tropical pathogen-induced B cell perturbations.

A retrospective study was undertaken to analyse the risk factors for systemic emboli in infective endocarditis. Patients (n = 80; 70% males; mean age 65 years; range 20-91 years) with infective endocarditis, as defined by the Duke criteria and diagnosed using transoesophageal echocardiography during the period January 1995 to March 2001, were included. The average time between the start of the illness and the beginning of antibiotic treatment was 55 days (range 0-405 days). The pathogens identified were streptococci (n = 47), staphylococci (n = 11), enterococci (n = 9), and others (n = 4). In nine cases, blood cultures were sterile. Thirty patients with at least one embolic episode were compared with 50 control patients. According to univariate analysis, the main risk factor for systemic emboli was the size of the vegetation (12.4 mm vs. 7.8 mm; p = 0.0005). The risk of emboli was 57% when the vegetation measured > 10 mm and only 22% when it was < 10 mm (p = 0.003). The mobility of the vegetation was also a risk factor: 48% if the vegetation was mobile; and 9% if fixed (p = 0.003). Sex, age, pathogen, antibiotic treatment, type of valve and the number and position of the vegetations were not found to be risk factors. With multivariate analysis, only mobility was identified as a risk factor. Overall, mobile vegetations > 10 mm in size were associated with an increased risk of embolic episodes in infective endocarditis.

Dengue fever (DF) is a mosquito-transmitted acute disease caused by any of four dengue flavivirus serotypes (DEN-1, DEN-2, DEN-3, and DEN-4) which is becoming a major public health problem in intertropical areas.1 DF is increasingly observed in febrile travelers returning from tropical areas,2 especially those returning from the Caribbean islands and Southeast Asia, but it is rarely diagnosed in travelers returning from Africa.3-8 Diagnosis is often serologic, and in most cases is not confirmed; virus isolation remains exceptional. In a retrospective study of 44 cases of imported DF diagnosed in France, we found that the epidemiologic, clinical and diagnostic characteristics of these cases were similar to those reported in other previous published studies; diagnosis was carried out with serology, and no virus isolation was reported. To draw the attention of physicians from nonendemic areas to the possible occurrence of dengue infection in febrile travelers from all tropical countries, including those in Africa, and to reinforce recommendations required to establish diagnosis with certainty, we report herein a prospective study from 1998-1999 which we compiled with our previously published data.

Cellulitis and necrotizing fasciitis can be distinguished by the depth of the cutaneous lesion and classically by the different bacteria implicated. This classification is not taken into account by the practitioner because of a similar therapeutic strategy. That is why most authors used a single title: necrotizing soft tissue infection. The potential severity of these infections required a quick diagnosis to decrease the risk of mortality and severe functional consequences. The analysis of the literature doesn't allow to establish the incidence of these infections. It was demonstrated that infections due to Streptococcus serogroup A increased over the last few years, thanks to a specific surveillance system. Risk factors leading to these infections are: cutaneous trauma, age, diabetes, varicella in children, contact with people infected by Streptococcus. The most recent studies demonstrated a frequent polymicrobism of the infections, with anaerobes, Streptococcus, Staphylococcus, and gram-negative rods. At the onset of the disease, the diagnosis is difficult to establish. Pain, induration of tissues, a rapid evolution, the inefficacy of antibiotic treatment suggest the diagnosis of necrotizing infection. MRI, when available, is a good technique to reveal the depth of the infection and necrosis. Surgery will confirm the diagnosis and allow for debridement of necrotized tissues. A delayed surgery increases the mortality risk factor, as stated in numerous studies.

Background: To study behavioral risk factors of Kaposi's sarcoma (KS) among HIV infected homosexuals in Bordeaux, southwest France., Methods: A case-control study was performed within the Aquitaine Cohort. Cases of KS surviving in 1995 and homosexuals were systematically enrolled. For each case, two controls were selected among homosexuals surviving in the cohort. Cases and controls were matched on year of diagnosis of HIV infection. Data collection was based on a self administered questionnaire focusing on use of recreational drugs, detailed sexual practices and sexually transmitted diseases in the year preceeding the diagnosis of HIV infection, in the year after the HIV diagnosis and in the year preceeding the diagnosis of KS (or an equivalent period of time for controls)., Results: Twelve cases were matched to 2 controls, 15 cases to one control and 13 cases remained unmatched. Matched analysis identified an association between KS and regular sexual partner (odds ratio = 0.07; 95% confidence interval: 0.01-0.52 and p < 0.001) and active and passive oro-anal intercourse before HIV diagnosis and before KS diagnosis (p = 0.01). In the unmatched analysis including all cases, we found an association between KS and the overall number of sexual partners (p < 0.03) for all periods of interest., Conclusions: This case-control study identified sexual practices in favor of a sexually transmitted agent of KS.

Objective: To assess secular trends of the incidence of Kaposi's sarcoma (KS) between 1988 and 1996 in the Aquitaine Cohort of human immunodeficiency virus type 1 (HIV1)-infected subjects (southwestern France)., Methods: Adults of both sexes of all HIV-transmission categories were included. We distinguished between incident and prevalent KS and in case of multiple acquired immunodeficiency syndrome (AIDS) defining illnesses between initial or subsequent KS. Only incident KS were considered for annual incidence rate calculation., Results: Overall, 21.2% (356/1678) of homosexuals and 1.9% (58/3030) of the other patients were diagnosed with KS over time. Although there was a sharp decrease in 1996 for initial KS, the annual incidence rate of KS was stable over time in the overall cohort as well as in homosexuals (4.3% per year on the average for KS as an initial AIDS-defining illness and 2.1% per year for subsequent KS in homosexuals). The median CD4+ cell count at the time of diagnosis of KS was 56 per mm3 (78 for initial KS, 14 for subsequent KS), with no significant variation over time., Conclusion: In the Aquitaine Cohort, the annual incidence of KS has remained stable between 1988 and 1995 with a recent decline in 1996, only for initial KS, while case management of HIV-infected subjects changed drastically.

Human herpesvirus 8 (HHV8) DNA was amplified from peripheral blood mononuclear cells (PBMCs) using PCR in 120 HIV-seropositive in- and outpatients who were enrolled in a cohort study between January 1994 and June 1995. Risk factors for HIV infection were homosexuality/bisexuality alone in 64 cases (30 with Kaposi's sarcoma (KS) and 34 without KS, 4 of whom had KS lesions that appeared during follow-up in the cohort), heterosexual contact alone in 32 cases (among whom 1 woman with KS who was the spouse of a bisexual with KS), and transfusion of blood or blood products alone in 24 cases. Three blood samples at 3-4-month intervals were scheduled for each patient. Twenty-five HIV1-seronegative patients served as controls. A total of 47.1% of homo- or bisexual males with KS and 26.7% of homo- or bisexual males without KS had positive HHV8 DNA detection as compared with 21.9% of patients contaminated by heterosexual contact, 8.3% of blood product recipients and 0% of controls. HHV8 DNA detection was intermittent in all but 3 patients according to sequential sampling. Multivariate analysis showed that AIDS-KS was associated with sexual transmission, mainly homo- or bisexual practices and with HHV8 infection assessed by PCR in PBMCs.

A 40 year-old man with the acquired immunodeficiency syndrome who was treated with intravenous pentamidine suffered a massive spontaneous haemorrhage caused by rupture of a pancreatic pseudocyst after pentamidine-induced pancreatitis. The patient previously presented symptomatic hypoglycaemia, severe nephrotoxicity and hyperkalaemia, while not receiving any other drug but pentamidine. This is the first case reported of such a complication of pentamidine induced pancreatitis, and one of the few cases reported of the latter adverse event.