Use of quantum dots in aqueous solution to detect blood fingermarks on non-porous surfaces.

A new and original reagent based on the use of highly fluorescent cadmium telluride (CdTe) quantum dots (QDs) in aqueous solution is proposed to detect weak fingermarks in blood on non-porous surfaces. To assess the efficiency of this approach, comparisons were performed with one of the most efficient blood reagents on non-porous surfaces, Acid Yellow 7 (AY7). To this end, four non-porous surfaces were studied, i.e. glass, transparent polypropylene, black polyethylene, and aluminium foil. To evaluate the sensitivity of both reagents, sets of depleted fingermarks were prepared, using the same finger, initially soaked with blood, which was then successively applied on the same surface without recharging it with blood or latent secretions. The successive marks were then cut in halves and the halves treated separately with each reagent. The results showed that QDs were equally efficient to AY7 on glass, polyethylene and polypropylene surfaces, and were superior to AY7 on aluminium. The use of QDs in new, sensitive and highly efficient latent and blood mark detection techniques appears highly promising. Health and safety issues related to the use of cadmium are also discussed. It is suggested that applying QDs in aqueous solution (and not as a dry dusting powder) considerably lowers the toxicity risks.

Serological survey of Babesia bovis, Babesia bigemina, and Anaplasma marginale antibodies in cattle from the semi-arid region of the state of Bahia, Brazil, by enzyme-linked immunosorbent assays

The objectives of this work were to determine the prevalence of Babesia bovis, Babesia bigemina, and Anaplasma marginale detecting antibodies in cattle raised in the semi-arid region of the state of Bahia, Brazil, through indirect enzyme linked immunosorbent assays (ELISA) and to compare the performances of indirect enzyme-linked immunosorbent assays with crude (I-ELISA-CrAnaAg) and recombinant major surface protein-5 (I-ELISA-MSP-5Ag), as antigens to detect antibodies against A. marginale. An stable enzootic area was found in Senhor do Bonfim and Euclides da Cunha for B. bovis that showed 86 and 95.5% of prevalence, respectively, and for B. bigemina with 90.8 and 91.3%. On the other hand, Uauá and Juazeiro, were characterized as enzootically unstable areas, since prevalences were: B. bovis - 63.7 and 56.4% and B. bigemina - 53 and 54.8%, respectively. The prevalence of A. marginale in the four municipalities was above 97% with I-ELISA-CrAnaAg and 94.8% with I-ELISA-MSP-5Ag which is an indication of stable enzootic condition for the rickettsia. The I-ELISA-CrAnaAg and I-ELISA-MSP-5Ag showed a highly significant association (r = 0.977), which means that both ELISA tests are suitable for epidemiological studies of A. marginale.

Evaluation of the GlideScope for tracheal intubation in patients with cervical spine immobilisation by a semi-rigid collar

RAPPORT DE SYNTHÈSE : Chez les patients présentant une pathologie de la colonne cervicale, l'instrumentation des voies aériennes peut s'avérer délicate. En effet, l'impossibilité d'effectuer une extension de la nuque afin d'aligner correctement l'axe oro-pharyngo-trachéal, ainsi que l'ouverture de bouche limitée par la présence d'une minerve cervicale, rendent la laryngoscopie standard extrêmement difficile. Le but de cette étude est de démontrer que l'intubation oro-trachéale avec une minerve cervicale semi-rigide est possible à l'aide d'un vidéolaryngoscope récemment développé, le GlideScope®. Celui-ci est formé d'une lame courbe présentant une angulation accentuée à 60° à partir de son milieu, avec une petite caméra haute résolution et une source lumineuse enchâssées dans la partie inférieure au point d'inflexion. Différents travaux ont montré les avantages du GlideScope® par rapport à la lame de Macintosh standard "pour l'instrumentation des voies aériennes de routine ou en situation difficile. Après acceptation par la Commission d'Ethique, 50 patients, adultes consentants et programmés pour une intervention chirurgicale élective nécessitant une anesthésie générale ont été inclus dans cette étude. Malgré la présence d'une minerve cervicale semi-rigide Philadelphia® Patriot correctement positionnée et la tête fixée à la table d'opération, tous les patients ont pu être intubés a l'aide du GlideScope®. Aucune complication n'a été documentée pendant la procédure ou en post-opératoire. De plus, nous avons démontré que dans cette situation la visualisation des structures laryngées est significativement améliorée grâce au GlideScope®, par rapport à la lame de Macintosh utilisée lors de toute intubation standard. En conclusion, l'intubation oro-trachéale chez les patients ayant une minerve cervicale et la tête fixée est possible à l'aide du GlideScope®. La meilleure façon de sécuriser les voies aériennes chez les patients présentant une instabilité de la colonne cervicale est un sujet fortement débattu. L'utilisation du GlideScope® pourrait s'avérer une alternative intéressante, en particulier dans les situations d'urgence.

Ectasie sclérale semi-annulaire pré-équatoriale chez un patient glaucomateux onchocerquien [Semi-annular pre-equatorial scleral ectasia in a patient with glaucoma and onchocerciasis].

We present the case of a glaucomatous young patient with onchocerciasis who developed a bilateral pre-equatorial scleral staphyloma with an important scleral thinness. The pathogenesis of anterior staphyloma is discussed: mechanical stress from very high ocular pressure, ocular onchocerciasis, scleral ischemia. A better understanding of scleral mechanical resistance could explain scleral thinness without any clinical scleritis.

Identification of human T-cell lymphotropic virus infection in a semi-isolated Afro-Brazilian quilombo located in the Marajó Island (Pará, Brazil)

Antibodies to human T-cell lymphotropic virus-1 and 2 (HTLV-1 and 2) were tested in 259 inhabitants (98 males and 161 females) of four villages of the Marajó Island (Pará, Brazil) using enzyme immunoassays (ELISA and Western blot). Types and subtypes of HTLV were determined by nested polymerase chain reaction (PCR) targeting the pX, env and 5´LTR regions. HTLV-1 infection was detected in Santana do Arari (2.06%) and Ponta de Pedras (1%). HTLV-2 was detected only in Santana do Arari (1.06%). Sequencing of the 5´LTR region of HTLV-1 and the phylogenetic analysis identified the virus as a member of the Cosmopolitan Group, subgroup Transcontinental. Santana do Arari is an Afro-Brazilian community and the current results represent the first report of HTLV-1 infection in a mocambo located in the Brazilian Amazon region.

Functionalization of microstructured open-porous bioceramic scaffolds with human fetal bone cells.

Bone substitute materials allowing trans-scaffold migration and in-scaffold survival of human bone-derived cells are mandatory for development of cell-engineered permanent implants to repair bone defects. In this study, we evaluated the influence on human bone-derived cells of the material composition and microstructure of foam scaffolds of calcium aluminate. The scaffolds were prepared using a direct foaming method allowing wide-range tailoring of the microstructure for pore size and pore openings. Human fetal osteoblasts (osteo-progenitors) attached to the scaffolds, migrated across the entire bioceramic depending on the scaffold pore size, colonized, and survived in the porous material for at least 6 weeks. The long-term biocompatibility of the scaffold material for human bone-derived cells was evidenced by in-scaffold determination of cell metabolic activity using a modified MTT assay, a repeated WST-1 assay, and scanning electron microscopy. Finally, we demonstrated that the osteo-progenitors can be covalently bound to the scaffolds using biocompatible click chemistry, thus enhancing the rapid adhesion of the cells to the scaffolds. Therefore, the different microstructures of the foams influenced the migratory potential of the cells, but not cell viability. Scaffolds allow covalent biocompatible chemical binding of the cells to the materials, either localized or widespread integration of the scaffolds for cell-engineered implants.

Clinical spectrum of uncomplicated malaria in semi-immune Amazonians: beyond the " symptomatic " vs " asymptomatic " dichotomy

We analyzed prospectively 326 laboratory-confirmed, uncomplicated malarial infections (46.3% due to Plasmodium vivax, 35.3% due to P. falciparum, and 18.4% mixed-species infections) diagnosed in 162 rural Amazonians aged 5-73 years. Thirteen symptoms (fever, chills, sweating, headache, myalgia, arthralgia, abdominal pain, nausea, vomiting, dizziness, cough, dyspnea, and diarrhea) were scored using a structured questionnaire. Headache (59.8%), fever (57.1%), and myalgia (48.4%) were the most frequent symptoms. Ninety-six (29.4%) episodes, all of them diagnosed during cross-sectional surveys of the whole study population (96.9% by molecular technique only), were asymptomatic. Of 93 symptom-less infections left untreated, only 10 became symptomatic over the next two months following diagnosis. Fever was perceived as " intense " in 52.6% of 230 symptomatic malaria episodes, with no fever reported in 19.1% episodes although other symptoms were present. We found significant differences in the prevalence and perceived intensity of fever and other clinical symptoms in relation to parasite load at the time of diagnosis and patient's age, cumulative exposure to malaria, recent malaria morbidity, and species of malaria parasite. These factors are all likely to affect the effectiveness of malaria control strategies based on active or passive detection of febrile subjects in semi-immune populations.

Evaluation of the GlideScope (R) for tracheal intubation in patients with cervical spine immobilisation by a semi-rigid collar

Application of cervical collars may reduce cervical spine movements but render tracheal intubation with a standard laryngoscope difficult if not impossible. We hypothesised that despite the presence of a Philadelphia Patriot (R) cervical collar and with the patient's head taped to the trolley, tracheal intubation would be possible in 50 adult patients using the GlideScope (R) and its dedicated stylet. Laryngoscopy was attempted using a Macintosh laryngoscope with a size 4 blade, and the modified Cormack-Lehane grade was scored. Subsequently, laryngoscopy with the GlideScope was graded and followed by tracheal intubation. All patients' tracheas were successfully intubated with the GlideScope. The median (IQR) intubation time was 50 s (43-61 s). The modified Cormack-Lehane grade was 3 or 4 at direct laryngoscopy. It was significantly reduced with the GlideScope (p < 0.0001), reaching grade 2a in most patients. Tracheal intubation in patients wearing a semi-rigid collar and having their head taped to the trolley is possible with the help of the GlideScope.

Biological activity of neosergeolide and isobrucein B (and two semi-synthetic derivatives) isolated from the Amazonian medicinal plant Picrolemma sprucei (Simaroubaceae)

In the present study, in vitro techniques were used to investigate a range of biological activities of known natural quassinoids isobrucein B (1) and neosergeolide (2), known semi-synthetic derivative 1,12-diacetylisobrucein B (3), and a new semi-synthetic derivative, 12-acetylneosergeolide (4). These compounds were evaluated for general toxicity toward the brine shrimp species Artemia franciscana, cytotoxicity toward human tumour cells, larvicidal activity toward the dengue fever mosquito vector Aedes aegypti, haemolytic activity in mouse erythrocytes and antimalarial activity against the human malaria parasite Plasmodium falciparum. Compounds 1 and 2 exhibited the greatest cytotoxicity against all the tumor cells tested (IC50 = 5-27 µg/L) and against multidrug-resistant P. falciparum K1 strain (IC50 = 1.0-4.0 g/L) and 3 was only cytotoxic toward the leukaemia HL-60 strain (IC50 = 11.8 µg/L). Quassinoids 1 and 2 (LC50 = 3.2-4.4 mg/L) displayed greater lethality than derivative 4 (LC50 = 75.0 mg/L) toward A. aegypti larvae, while derivative 3 was inactive. These results suggest a novel application for these natural quassinoids as larvicides. The toxicity toward A. franciscana could be correlated with the activity in several biological models, a finding that is in agreement with the literature. Importantly, none of the studied compounds exhibited in vitro haemolytic activity, suggesting specificity of the observed cytotoxic effects. This study reveals the biological potential of quassinoids 1 and 2 and to a lesser extent their semi-synthetic derivatives for their in vitro antimalarial and cytotoxic activities.

Semi-online neural-Q_leaming for real-time robot learning

Reinforcement learning (RL) is a very suitable technique for robot learning, as it can learn in unknown environments and in real-time computation. The main difficulties in adapting classic RL algorithms to robotic systems are the generalization problem and the correct observation of the Markovian state. This paper attempts to solve the generalization problem by proposing the semi-online neural-Q_learning algorithm (SONQL). The algorithm uses the classic Q_learning technique with two modifications. First, a neural network (NN) approximates the Q_function allowing the use of continuous states and actions. Second, a database of the most representative learning samples accelerates and stabilizes the convergence. The term semi-online is referred to the fact that the algorithm uses the current but also past learning samples. However, the algorithm is able to learn in real-time while the robot is interacting with the environment. The paper shows simulated results with the "mountain-car" benchmark and, also, real results with an underwater robot in a target following behavior

L'arrêt cardio-respiratoire (ACR) au cabinet médical est-il une réalité et y a-t-il nécessité de s'équiper d'un défribillateur semi-automatique (DSA)?

Introduction: Cette étude a pour but de déterminer la fréquence de survenue de l'arrêt cardio-respiratoire (ACR) au cabinet médical qui constitue un élément de décision quant à la justification de la présence d'un défibrillateur semi-automatique (DSA) au cabinet médical. Matériel et Méthode: Analyse rétrospective des fiches d'intervention pré-hospitalière des ambulances et des SMUR (Service Mobile d'Urgence et de Réanimation) du canton de Vaud (650'000 habitants) entre 2003 et 2006 qui relataient un ACR. Les variables suivantes ont été analysées: chronologie de l'intervention, mesures de réanimation cardio-pulmonaire (RCP) appliquées, diagnostic présumé, suivi à 48 heures. Résultats: 17 ACR (9 _, 8 _) ont eu lieu dans les 1655 cabinets médicaux du canton de Vaud en 4 ans sur un total de 1753 ACR extrahospitaliers, soit 1% de ces derniers. Tous ont motivés une intervention simultanée d'une ambulance et d'un SMUR. L'âge moyen était de 70 ans. Le délai entre l'ACR et l'arrivée sur site d'un DSA était en moyenne de plus de 10 minutes (min-max: 4-25 minutes). Dans 13 cas évaluables, une RCP était en cours à l'arrivée des renforts, mais seulement 7 étaient qualifiées d'efficaces. Le rythme initial était une fibrillation ventriculaire (FV) dans 8 cas et ont tous reçu un choc électrique externe (CEE), dont 1 avant l'arrivée des secours administré dans un cabinet équipé d'un DSA. Le diagnostic était disponible pour 9 cas: 6 cardiopathies, 1 embolie pulmonaire massive, 1 choc anaphylactique et 1 tentamen médicamenteux. Le devenir de ces patients a été marqué par 6 décès sur site, 4 décès à l'admission à l'hôpital et 7 vivants à 48 heures. Les données ne permettent pas d'avoir un suivi ni à la sortie de l'hôpital ni ultérieurement. Conclusions: Bien que la survenue d'un ACR soit très rare au cabinet médical, il mérite une anticipation particulière de la part du médecin. En effet, le délai d'arrivée des services d'urgences nécessite la mise en oeuvre immédiate de mesures par le médecin. En outre, comme professionnel de la santé, il se doit d'intégrer la chaîne de survie en procédant à une alarme précoce du 144 et initier des gestes de premier secours («Basic Life Support»). La présence d'un DSA pourrait être envisagée en fonction notamment de l'éloignement de secours professionnels équipés d'un DSA.

Validation and reproducibility of a semi-quantitative Food Frequency Questionnaire for use in elderly Swiss women.

OBJECTIVE: The principal aim of this study was to develop a Swiss Food Frequency Questionnaire (FFQ) for the elderly population for use in a study to investigate the influence of nutritional factors on bone health. The secondary aim was to assess its validity and both short-term and long-term reproducibility. DESIGN: A 4-day weighed record (4 d WR) was applied to 51 randomly selected women of a mean age of 80.3 years. Subsequently, a detailed FFQ was developed, cross-validated against a further 44 4-d WR, and the short- (1 month, n = 15) and long-term (12 months, n = 14) reproducibility examined. SETTING: French speaking part of Switzerland. SUBJECTS: The subjects were randomly selected women recruited from the Swiss Evaluation of the Methods of Measurement of Osteoporotic Fracture cohort study. RESULTS: Mean energy intakes by 4-d WR and FFQ showed no significant difference [1564.9 kcal (SD 351.1); 1641.3 kcal (SD 523.2) respectively]. Mean crude nutrient intakes were also similar (with nonsignifcant P-values examining the differences in intake) and ranged from 0.13 (potassium) to 0.48 (magnesium). Similar results were found in the reproducibility studies. CONCLUSION: These findings provide evidence that this FFQ adequately estimates nutrient intakes and can be used to rank individuals within distributions of intake in specific populations.