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Un cas de tuberculose pulmonaire bactériologiquement confirmée (TPB+) non traitée, constitue un réservoir pour la transmission de la maladie. Cette étude avait pour objectif d’évaluer le délai et d'identifier les déterminants du retard diagnostic de la TPB+ dans les centres de diagnostic et de traitement de la tuberculose (CDT) à Bangui.

Background: Gestational diabetes mellitus (GDM) is not merely a temporary condition, but a harbinger of type 2 diabetes mellitus, hypertension, and atherosclerotic disease. We examined the effect of GDM on cardiac diastolic function. Methods: Diastolic function was evaluated by serial Doppler echocardiography with pulsed tissue Doppler imaging in 13 patients with GDM and 13 healthy pregnant women (control group) during the third trimester of pregnancy and after 8 weeks postpartum. Diagnostic criteria for GDM were those as recommended by the American Diabetes Association. Exclusion criteria were any disease or condition that could interfere with diastolic function. Measurements at both times in each group were compared by paired t tests and changes of patients with diabetes were compared with those in control patients by unpaired t tests. Results: There were no differences in age, left ventricular mass, or systolic function between groups. The Doppler parameters that showed significant difference between groups were higher atrial contraction wave (A wave) (P = .008) and lower rapid filling wave (E)/A ratio (P = .006) in diabetic group, on both occasions. Tissue Doppler parameters showed a significant decrease in Em (P = .002) and early mitral annulus velocity (Em)/late mitral annulus velocity (Am) (P = .008) in diabetic group on both occasions, and the Am wave remained increased only in the diabetic group at postpartum. Conclusions: Patients with GDM showed a different diastolic function profile, suggesting a mild degree of diastolic abnormality. The persistence of some abnormalities postpartum corroborates our hypothesis of an early cardiovascular involvement in this group, enhancing the need of a close cardiovascular follow-up of these patients.

This paper offers an overview of existing international monitoring systems with relevance for environmental health surveillance. Representative monitoring systems are described that: address areas of chronic and acute exposure, and diseases and behavioural effects resulting from human-environment interactions; have an ecosystem focus with perhaps a secondary motivation of ascertaining human health impacts that may result from ecosystem conditions; and that incorporate socio-demographic and economic data that may reflect population health determinants. General conclusions on the state of environmental surveillance systems and suites of indicators reviewed are provided in relation to their utility for the development of a generic environmental health surveillance system. This review indicates, among other things, that no obvious short list of core indicators exists which spans “environmental health” to provide a sufficient set applicable in a global context. Through a summary of challenges and limitations in existing systems and indicator sets, recommendations are provided for the discussion of indicator selection and organization, and of developing general and widely applicable environmental health monitoring and surveillance systems. Dans cet article, les auteurs présentent un survol des réseaux de surveillance internationaux en matière d’hygiène de l’environnement. Ils décrivent des réseaux de surveillance typiques de secteurs d’exposition chronique et aiguë, de maladies et d’effets sur le comportement liés aux interactions entre les humains et l’environnement. De tels réseaux sont centrés sur les écosystèmes et ont peut-être comme intérêt secondaire l’évaluation des impacts des conditions de l’écosystème sur la santé humaine. Ils comprennent aussi des données sociodémographiques et économiques qui peuvent être à l’image des déterminants de la santé de la population. Les auteurs analysent l’état des réseaux de surveillance environnementale et étudient des groupes d’indicateurs en fonction de leur utilité pour la mise sur pied de réseaux de surveillance générale de l’hygiène de l’environnement, et tirent des conclusions générales à ce sujet. Ils soulignent notamment qu’il n’existe pas de présélection évidente d’indicateurs de base couvrant l’hygiène de l’environnement et applicables au contexte planétaire. À l’aide d’une synthèse des problèmes et des limites des réseaux et des groupes d’indicateurs actuels, les auteurs émettent des recommandations quant à l’analyse du choix et de l’organisation des indicateurs et quant à la construction de réseaux de surveillance de l’hygiène de l’environnement de portée générale et applicables à grande échelle.

Abstract: The effects of drift angle on model ship flow are investigated through towing tank tests for the Series 60 CB=0.6 cargo/container model ship. Resistance, side force, drift moment, sinkage, trim, and heel data are procured for a range of drift angles β and Froude numbers (Fr) and the model free condition. Detailed free-surface and mean velocity and pressure flow maps are procured for high and low Fr=0.316 and 0.16 and β=5° and 10° (free surface) and β=10° (mean velocity and pressure) for the model fixed condition (i.e. fixed with zero sinkage, trim, and heel). Comparison of results at high and low Fr and previous data for β=0° enables identification of important free-surface and drift effects. Geometry, conditions, data, and uncertainty analysis are documented in sufficient detail so as to be useful as a benchmark for computational fluid dynamics (CFD) validation. The resistance increases linearly with β with same slope for all Fr, whereas the increases in the side force, drift moment, sinkage, trim, and heel with β are quadratic. The wave profile is only affected near the bow, i.e. the bow wave amplitude increases/decreases on the windward/leeward sides, whereas the wave elevations are affected throughout the entire wave field. However, the wave envelope angle on both sides is nearly the same as β=0°, i.e. the near-field wave pattern rotates with the hull and remains within a similar wave envelope as β=0°. The wave amplitudes are significantly increased/decreased on the windward/leeward sides. The wake region is also asymmetric with larger wedge angle on the leeward side. The boundary layer and wake are dominated by the hull vortex system consisting of fore body keel, bilge, and wave-breaking vortices and after body bilge and counter-rotating vortices. The occurrence of a wave-breaking vortex for breaking bow waves has not been previously documented in the literature. The trends for the maximum vorticity, circulation, minimum axial velocity, and trajectories are discussed for each vortex.

Abstract: Unsteady resistance, heave force, pitch moment and free-surface elevations for DTMB 5512 at steady forward speed and in regular head waves are investigated with different measurement systems for a fairly wide range of test conditions in the IIHR towing tank. Test data are procured for validation of Reynolds-averaged Navier–Stokes computational fluid dynamics codes and for understanding the physics of unsteady ship hydrodynamics. The second part of the paper presents the measurement results and discussions.

Abstract: A model-scale naval surface combatant, DTMB 5512, is studied experimentally in steady forward speed and regular head waves with the Iowa Institute of Hydraulic Research towing-tank facilities. Unsteady resistance, heave force, pitch moment and free-surface elevations are investigated with different measurement systems for a fairly wide range of test conditions. Test data is procured for validation of RANS computational fluid dynamics codes and for understanding the physics of unsteady ship hydrodynamics. In the first part of the two-part paper, details of data reductions, measurement systems and uncertainty assessment procedures are provided.

Abstract: Objective: To compare noncontrast helical computed tomography (NCHCT) and intravenous urography (IVU) for diagnosis of urinary calculi in evaluation of renal colic. Materials and methods: A 4-month prospective paired study compared NCHCT and IVU in patients being evaluated for renal colic. Each patient was studied with NCHCT followed by an IVU. An IVU was regarded as positive if any of the following were identified: delayed filling, hydronephrosis, hydroureter, ureteral calculus, or extravasation of contrast. A NCHCT was regarded as positive if any of the following were identified: hydronephrosis, hydroureter, ureteral calculus, or perinephric or ureteral inflammatory change. The sensitivity (Se), specificity (Sp), positive predictive value (PPV), and negative predictive value (NPV) were reported using the clinical outcome as the gold standard, by either observation of passage or retrieval of calculus. Bladder distention was noted on NCHCT relative to the level of the acetabulum. The charts were also reviewed retrospectively for the results of urinalysis. Results: One hundred sixty-eight patients had both examinations interpreted. Nineteen positive NCHCT and IVU studies were eliminated due to lack of observation or retrieval of calculus, leaving 149 studies for interpretation. NCHCT had Se 0.98, Sp 0.95, PPV 0.98, and NPV 0.95. IVU had Se 0.83, Sp 0.95, PPV 0.97, and NPV 0.67. In 13/168 (8 %) cases, and in 9/37 (24 %) negative cases, NCHCT offered an alternative diagnosis. Ureterovesical junction (UVJ) calculus was identified on 84 NCHCT scans, with near-even distribution between well, partially, and poorly distended bladder. No UVJ calculus was identified on IVU that was not present on NCHCT. Absence of hematuria was found in 26 % of patients with proven urolithiasis. Conclusion: NCHCT is superior to IVU for the evaluation of renal colic. NCHCT identifies significant pathology in 24 % of cases negative for ureteral obstruction/calculus. Bladder distention does not play an important role in detection of UVJ calculus. Hematuria is not universally present in patients with painful urolithiasis.

Abstract:  A towed PIV system designed by DANTEC Measurement Technology for the Iowa Institute of Hydraulic Research towing tank is commissioned by measuring the mean velocity and Reynolds stresses at the nominal-wake plane of a model-scale ship. The mean velocities are compared with previous 5-hole pitot probe data. Uncertainty assessment following standard procedures is used to quantify the comparisons and reach conclusions regarding the quality of the data. The PIV results are analyzed with regard to axial velocity defects, axial vorticity, and level, pattern and anisotropy of turbulence. Quantitative comparisons with 5-hole pitot data shows that PIV uncertainties are about 1% lower than those for 5-hole pitot. However, data differences are larger than RSS of PIV and 5-hole pitot uncertainties for the axial and vertical velocity components, indicating unaccounted for bias and precision limits. The bias error of the pitot probe in a shear flow is discussed, and a method for reducing the bias error is suggested. The data is being used for verification and validation of RANS simulation of DTMB Model 5512.

Abstract: Influences of evaluation bias of the correlation-based interrogation algorithm on particle image velocimetry (PIV) measurement of turbulent flow are investigated. Experimental tests in the Iowa Institute of Hydraulic Research towing tank with a towed PIV system and a surface-piercing flat plate and simulations demonstrate that the experimentally determined mean velocity and Reynolds stress components are affected by the evaluation bias and the gradient of the evaluation bias, respectively. The evaluation bias and gradient of the evaluation bias can both be minimized effectively by using Gaussian digital masks on the interrogation window, so that the measurement uncertainty can be reduced.

Hyperthermia is known to synergistically interact with X-rays to kill cells. We have used pulsed-field gel electrophoresis to investigate the effects of hyperthermia on cell survival and on repair of radiation-induced DNA double-strand breaks (dsbs). Combining hyperthermia (43°°C, 45 min) with radiation (7.5 Gy) resulted in a complete inhibition of dsb repair and a surviving fraction of 0··9%. Cells treated with hyperthermia alone resulted in a 55% cell survival with no increase in dsb levels over background. Cells treated with 7··5 Gy alone demonstrated 11% survival and exponential dsb repair. Dsb repair was equally inhibited by hyperthermia whether administered immediately before or after the radiation. We compared the rejoining of dsbs resulting from 7··5 Gy at 37 and 43°°C to determine whether dsbs were being repaired during hyperthermia. While repair occurred at 37°°C, no dsbs were repaired at 43°°C. Our results indicate that hyperthermia completely inhibits dsb repair.

Abstract:  The Reynolds-averaged flow for a solid/free-surface juncture boundary layer and wake is documented. The three mean-velocity components and five of the Reynolds stresses are measured for a surface-piercing flat plate in a towing tank using a laser-Doppler velocimeter system for both boundary-layer and wake planes in regions close to the free surface. The experimental method is described, including the foil-plate model, laser-Doppler velocimeter system, conditions, and uncertainty analysis. The underlying flow data is in excellent agreement with benchmark data. Inner (near the plate and wake centerplane and below the free surface) and outer (near the free surface) regions of high streamwise vorticity of opposite sign are observed, which transport, respectively, high mean velocity and low turbulence from the outer to the inner and low mean velocity and high turbulence from the inner to the outer portions of the boundary layer and wake. For the wake, the inner region of vorticity is relatively weak. The physical mechanism for the streamwise vorticity is analyzed with regard to the Reynolds-averaged streamwise vorticity equation. The anisotropy of the crossplane normal Reynolds stresses closely correlates with the vorticity and, additionally, indicates similarity, i.e., its nature is such that it only depends on the proximity to the plate and free surface boundaries or wake centerplane symmetry plane. Free-surface effects on the Reynolds stresses are analyzed with regard to the behavior close to the free surface of the turbulent kinetic energy and the normal components of the anisotropy tensor and the anisotropy invariants. Close to the free surface, the turbulent kinetic energy is nearly constant and increases for the inner and outer portions, respectively, of the boundary layer and wake and the normal components of the anisotropy tensor and the anisotropy invariants roughly correspond to the limiting values for two-component turbulence. The similarities and differences between the present results and analysis with those from related studies are discussed. The data and analysis should have practical application with regard to the development of turbulence models for computational fluid dynamics methods for the Reynolds-averaged Navier–Stokes equations.

Plasma kallikrein and factor XIa circulate bound to high molecular weight kininogen, and such binding has been reported to protect these enzymes from inactivation by their respective inhibitors. However, this observation is controversial, and the effect of high molecular weight kininogen upon the interaction between kallikrein and C1 inhibitor (C1-INH) has been questioned. We have re-evaluated this reaction and studied the rate of inhibition of kallikrein by C1-INH in the presence and absence of high molecular weight kininogen. The second-order rate constant of inhibition of kallikrein by C1-INH was unaffected by saturating concentrations of high molecular weight kininogen. Our results suggest that although high molecular weight kininogen clearly augments the rate of formation of kallikrein and other enzymes of the contact activation pathway, it has no effect on the rate of enzyme inhibition by C1-INH.

The morphologic changes in the fetal membranes and uterine wall were studied sequentially in 8 rhesus monkeys at midgestation following replacement of amniotic fluid with 20 per cent sodium chloride. The saline solution caused a rapid stasis of the umbilical and decidual circulations as a result of dense intravascular aggregation or compaction of red blood cells. Later, small-sized blood vessels throughout the uterine wall not protected by the placenta also showed stoppage of flow. The umbilical blood flow stasis caused rapid death of the fetus from asphyxia while stoppage of the decidual circulation caused decidual necrosis. Thromboplastin release from the necrotic decidua caused a superadded intravascular coagulation with blockage of not only the remaining small blood vessels but also the entire uterine venous drainage system. The severe reductions in uterine blood flow with damage to blood vessel walls led to myometrial edema and multiple subserosal and intramural hemorrhages. After 24 to 48 hours, these combined changes led to a Couvelaire-type uterus. Uterine contractions appeared within 15 minutes of instillation of saline, and a laborlike activity evolved despite the progressive impairment of uterine perfusion and myometrial edema.

The frequency dependence of the electron-paramagnon spectrumP(O) in Pd is calculated within the finite bandwidth model. It is found that for an almost full band, the magnitude, the range, and the position of the peak frequency inP(O) are dramatically reduced compared to their values in the usual paramagnon theory. Also, we find that the frequency dependence of the spin-fluctuation contribution to the electron self-energy is strongly affected by a close proximity of the Fermi level to the top of the band. We speculate that an unusually large value of the Coulomb pseudopotential is probably partially responsible for the absence of superconductivity in Pd.

Unrestricted Hartree−Fock and density functional theory calculations have been carried out to investigate the detailed kinetics and mechanisms of hydrocarbon thermal cracking. The calculations of the elementary reactions involved in the overall cracking of paraffin molecules agree well with the generally accepted free radical mechanism. The results can be summarized as follows:  (1) Initiation cracking, the calculated bond dissociation energy (BDE) for C−C homolytic scission is ~95 kcal/mol at the MP2/6-31G* level and ~89 kcal/mol at the B3LYP/6-31G* level. No transition states are found in the reactions. (2) H-transfer reaction, the calculated energy barriers (activation energy) are 15−17 kcal/mol at the MP2/6-31G* level and 10−12 kcal/mol at the B3LYP level. The reverse reaction has about the same energy barrier. The calculated transition state structures for both reactions lie in the middle between the reactant and product. (3) Radical decomposition−“β scission”, the activation energy for the radical decomposition is calculated to be 30−33 kcal/mol. The activation energy for the reverse addition reaction is 5 kcal/mol. The optimized transition state structure is product-like for the radical decomposition reaction and reactant-like for the addition reaction.

From 1982 to 1989, 18 eligible patients (median age 50.5 years, range 30–72 years) with inflammatory breast carcinoma have been treated with neoadjuvant intra-arterial (IA) chemotherapy. The treatment regimen includes IA cisplatin, adriamycin, mytomycin C and thiotepa on Day 1 and intravenous 5-fluorouracil on Days 1 and 2. An objective clinical response rate of 100% (eight complete and 10 partial) has been observed. The median disease-free and overall survivals are 27 months (range 5–85 + months) and 33 months (range 8–85 + months), respectively. With a median follow-up of 21.5 months, six (33.3%) patients remain alive and free of disease and 12 patients have died because of distant metastases. No local recurrences have been observed. Intra-arterial chemotherapy is an attractive technique for the treatment of locally advanced breast carcinoma with mild toxicity and high local control rate.

The development of double-minute chromosomes (DMs) and subsequent gene amplification are important genomic alterations resulting in increased oncogene expression in a variety of tumors. The molecular mechanisms mediating the development of these acentric extrachromosomal elements have not been completely defined. To elucidate the mechanisms involved in DM formation, we have developed strategies to map amplified circular DM DNA. In this study, we present a long-range restriction map of a 980-kb DM. A cell line cloned from mouse EMT-6 cells was developed by stepwise selection for resistance to methotrexate. This cloned cell line contains multiple copies of the 980-kb DM carrying the dihydrofolate reductase (DHFR) gene. A long-range restriction map was developed in which a hypomethylated CpG-rich region near the DHFR gene served as a landmark. This strategy was combined with plasmid-like analysis of ethidium bromide-stained pulsed-field gels and indicated that a single copy of the DHFR gene was located near a hypomethylated region containing SsII and NotI sites. At least 490 kb of this DM appears to be composed of unrearranged chromosomal DNA.

Abstract: High quality InAsxSbyPl-x-y quaternary layers, which are lattice matched to InAs, have been grown successfully on InAs substrates by liquid phase epitaxy. Both Graded and constant composition InAsxSbyPl-x-y layers have been grown. In addition, the graded InAsxSbyPl-x-y layer has been used as a buffer layer for the growth of InAsl-xSbx on an InAs substrate.

To determine whether microscopically visible double-minute chromosomes (DMs) are derived from submicroscopic precursors, we monitored the amplification of the dihydrofolate reductase (DHFR) gene in 10 independent isolates of methotrexate (MTX)-resistant mouse cells. At every other doubling in MTX concentration, the cells were examined both microscopically, to detect the presence of microscopically visible DMs, and by pulsed-field gel electrophoresis and hybridization to a DHFR-specific probe, to detect submicroscopic DMs. One of the cloned MTX-resistant isolates was examined in detail and was shown to originally contain amplified DHFR genes on circular DMs measuring 1 and 3 Mb in size; additionally, metaphase chromosome preparations from this cloned isolate were examined and were shown to contain microscopically visible DMs too large to enter a pulsed-field gel. During stepwise selection for increasing levels of MTX, the smaller DMs (not microscopically visible) were shown to be preferentially amplified, whereas the larger (microscopically visible) ones decreased in relative numbers. Rare-cutting NotI digestion patterns of total genomic DNA that includes the DMs containing the DHFR gene suggest that the DMs increase in copy number without any further significant rearrangements. We saw no evidence from any of the 10 isolates to suggest that microscopically visible DMs are formed from smaller submicroscopic precursors.

We report a case of primary amyloidosis affecting the kidney and presenting as a renal infraction on computed tomography and ultrasound examination. To our knowledge, it is the first case in the radiological literature with these imaging characteristics.

Nowadays, ultrasound examination is routinely utilized in the diagnosis of acute cholecystitis and its complications. Perforation of the gallbladder wall is usually suspected from indirect, non-specific sonographic findings, i.e.pericholecystic fluid collections, free peritoneal fluid, irregular gallbladder wall thickening, gallbladder distention, gallstones, coarse intracholecystic echogenic debris, and a complex mass in the gallbladder fossa (Forsberg et al, 1988; Chen et al, 1990). Sonographic visualization of the gallbladder perforation itself is rarely achieved (Chau et al, 1988; Takada et al, 1989; Chen et al, 1990). We report a case in which colour Doppler sonography allowed direct visualization of the biliary leakage across the gallbladder wall, thus providing the diagnosis. In addition, percutaneous catheter drainage of both the gallbladder and adjacent collection allowed the perforation to heal, hence avoiding surgery.

IN connexion with attempts to incorporate more divalent (rather than trivalent) samarium into calcium fluoride single crystals, and thereby make them more efficient optical maser materials1, we have observed changes in the electron spin resonance and optical absorption bands of X-irradiated samarium-doped fluorite crystals, which indicate that by ionizing radiation the valency of the samarium may be adjusted in a favourable manner after the samarium has been incorporated in the crystal.