[Invasive squamous cell carcinoma: about 2 cases]. / Carcinome épidermoïde conjonctival invasif : à propos de 2 cas.

Conjunctival tumors are common in tropical areas, where exposure to ultraviolet radiation is high and almost permanent. Malignant tumors are quite rare and the most represented is conjunctival squamous cell carcinoma. We report two cases of invasive squamous cell carcinoma of the conjunctiva received in the ophthalmology department of the Sominé Dolo hospital in Mopti, Mali. The patients were 25 and 51 years old, living in a rural desert area exposed to sunlight and dust. They presented with a mass developed in the area of the palpebral fissure, invading the cornea and preventing palpebral occlusion. The mass was raised, multi-lobulated, well circumscribed, pearly white in color and papillomatous in appearance with dilation of the feeder vessels. A wide surgical excision at 4 - 5 mm from the healthy tissue edges was performed with anatomopathological examination of the specimen, which confirmed a mature and invasive differentiated squamous cell carcinoma of the conjunctiva. The extension workup and HIV serology were negative. The evolution was favorable in the medium term without recurrence.

Les tumeurs conjonctivales sont fréquentes dans les zones tropicales,où l'exposition aux rayons ultraviolets est forte et quasi permanente. Les tumeurs malignes sont assez rares et la plus représentée est le carcinome épidermoïde de la conjonctive.Nous rapportons deux cas de carcinome épidermoïde invasif de la conjonctive reçus dans le service d'ophtalmologie de l'hôpital Sominé Dolo de Mopti au Mali. Il s'agissait de deux patientes de 25 et 51 ans, vivant en zone rurale et désertique exposées aux rayons solaires et à la poussière. Elles présentaient une masse développée dans l'aire de la fente palpébrale, envahissant la cornée et empêchant l'occlusion palpébrale. La masse était en relief, multi lobulée, bien circonscrite, de couleur blanc nacré et d'aspect papillomateux avec une dilatation des vaisseaux nourriciers. Une exérèse chirurgicale large à 4 - 5 mm des berges de tissu sain a été réalisée avec examen anatomopathologique de la pièce qui a confirmé un carcinome épidermoïde différencié mature et invasif de la conjonctive. Le bilan d'extension et la sérologie HIV étaient négatifs. L'évolution était favorable à moyen terme sans récidive.

Symmetric and asymmetric shocked gas jets for laser-plasma experiments.

Shocks in supersonic flows offer both high density and sharp density gradients that are used, for instance, for gradient injection in laser-plasma accelerators. We report on a parametric study of oblique shocks created by inserting a straight axisymmetric section at the end of a supersonic "de Laval" nozzle. The effect of different parameters, such as the throat diameter and straight section length on the shock position and density, is studied through computational fluid dynamics (CFD) simulations. Experimental characterizations of a shocked nozzle are compared to CFD simulations and found to be in good agreement. We then introduce a newly designed asymmetric shocked gas jet, where the straight section is only present on one lateral side of the nozzle, thus providing a gas profile well adapted for density transition injection. In this case, full-3D fluid simulations and experimental measurements are compared and show excellent agreement.

[Efficacy and tolerance of Latanoprost given as a first intention in the treatment of primitive open angle glaucoma in African melanoderm]. / Efficacité et tolérance du Latanoprost donné en première intention dans le traitement du glaucome primitif a angle ouvert chez le mélanoderme africain.

OBJECTIVE: To assess the reduction in IOP and ocular symptoms in patients newly diagnosed with POAG and treated with latanoprost as monotherapy. PATIENTS AND METHOD: A multicentric, cross-sectional, descriptive study was conducted. We included adults newly diagnosed with POAG. All patients received one drop of preserved latanoprost 0.005% in each eye every night for 12 weeks. Changes in IOP and ophthalmic signs and symptoms were assessed during and at the end of treatment. RESULTS: A total of 524 patients were included, with a participation rate of 93% at 12 weeks. The mean age was 52.79±17.33 years, and the sex ratio M/F was 1.39. At inclusion, the mean IOP was 21.68±9.72mmHg. After 2 weeks of treatment, the mean IOP was 15.49±5.81mmHg, for a reduction of 28.55%. After 12 weeks of treatment, the mean IOP was 13.16±3.54mmHg, for a reduction of 39.30%. The main symptom recorded was a gritty foreign body sensation, the frequency of which was 4.72% at W2 and 2.45% at W12. The main sign was hyperemia (4.33% at W2 and 1.84% at W12). CONCLUSION: Latanoprost given as first-line monotherapy in POAG in blacks considerably reduces IOP. The incidence of side effects remains low; it is higher at the start of treatment.

[Eye traumatism during the COVID-19 sanitary crisis at Iota-teaching hospital]. / Traumatismes oculaires pendant la crise sanitaire de COVID-19 au CHU de Iota.

INTRODUCTION: During the COVID-19 pandemic, we have witnessed a world-wide lock-down of the population. This government action combined with the application of social distancing should in principle reduce the frequency of occurrence of ocular injuries. The goal of our work is to try to understand the circumstances of the occurrence of ocular injuries at the IOTA Teaching Hospital during the lock-down period of the COVID-19 health crisis. METHODOLOGY: This was a cross-sectional, descriptive study. The data were collected prospectively. Our study covered the period from March to May 2020. All consenting patients seen at the IOTA Teaching Hospital for ocular trauma regardless of gender, age, circumstances in which the trauma occurred or the nature of the injuries were included by non-probability sampling. Excluded from the study were patients who did not consent or who consulted for a non-traumatic ophthalmologic condition. RESULTS: There were a total of 138 cases, of which 84 were male and 54 female, for a gender ratio of M/F=1.5. Children aged 0 to 5 years represented more than 3/4 (79.14%) of our sample. Trauma occurred in 45.83% of cases during leisure activities and 3.60% of cases involved domestic violence. DISCUSSION: According to the authors, measures aimed at limiting public movement, particularly the curfews introduced by the Malian government to contain the spread of the COVID-19 pandemic, may actually result in trauma. CONCLUSION: Raising public awareness of the social and psychological consequences of lock-down through audiovisual means might significantly reduce the frequency of these ocular traumas.

Neonatal ophthalmia in Mali.

A newborn 3 hours old newborn presented bilateral eyelid edema with erythema and inflammatory hypertrophy of the palpebral conjunctiva. PCR of the conjunctival swabbing showed the presence of Chlamydia trachomatis DNA. Treatment with erythromycin suspension 125 mg/5 ml was initiated, supplemented by topical application of oxytetracycline ointment 1% and Azyter eye drops.

[Evaluation of the quality of life of adult patients treated in low vision at the CHU-IOTA]. / Évaluation de la qualité de vie des patients adultes pris en charge en basse vision au CHU-IOTA.

INTRODUCTION: Visual impairment is a handicap defined as any alteration of visual function responsible for a partial or total limitation of the activities of daily living (OMS, 2004). The objective of this study is to assess quality of life in patients before and after management of low vision. PATIENTS AND METHODS: This was a mono-centric, transverse, analytical study over a period of 6 months. Our study population included all adult patients seen in ophthalmologic consultation and followed in the low vision unit with visual acuity less than 3/10 and greater than or equal to 1/20 in the best eye with best optical correction. The National Eye Institute's quality of life questionnaire, the NEF VFQ 25, was administered to patients on site prior to management and then a month later. RESULTS: Low-vision management improved overall the dimensions of the quality of life questionnaire. Following the end-of-care assessment, the score for ocular pain was lowest (38.20), followed by the overall vision score (44.95) and near vision difficulty score (45.33). DISCUSSION: Our sample population was distinguished by a cultural mix, with diversity of beliefs and lifestyles, and also by the relatively advanced age of the subjects constituting it. This can influence the individual's perception of him- or herself within his or her environment, modifying the patient's estimation of his or her condition and therefore his or her behavior. CONCLUSION: Low-vision rehabilitation can improve the quality of life of visually impaired patients, particularly for near vision, activities of daily living and psychological health.

[Assessment of quality of life in patients with primary open-angle glaucoma in urban areas]. / Evaluation de la qualite de vie chez les patients atteints de glaucome primitif a angle ouvert en milieu urbain.

INTRODUCTION: Quality of life is defined by the physical, emotional and social well-being of an individual. Primary Open Angle Glaucoma (POAG) is a blinding optic neuropathy, it can change the quality of life by its chronic and irreversible nature. The objective of this study was to evaluate the quality of life in patients with POAG in urban areas. PATIENTS AND METHODS: this was a quantitative cross-sectional study with a descriptive aim over 3 months. Patients followed for POAG at CHU-IOTA with an age ≥ 18 years were included and submitted to the GlauQOL-17 questionnaire for data collection. RESULTS: We collected 100 glaucomatous patients, the mean age of patients was 52 years with a standard deviation of 14.02. The extreme ages are 18 and 81 years old. There was a male predominance; (54%) with a sex ratio (M / F) of 1.7. The good visual acuities were majority (higher or equal to 3/10). Among our patients, 35% were at the stage of glaucoma starting at OD and 30% at the stage of moderate glaucoma at OG. Our patients had a poor quality of life score (score <50%) in the Anxiety and Driving dimensions. In patients younger than 70 years old, we had a poor anxiety score in all progressive stages of the disease. Scores of self-image dimensions, constraints, and management were greater than 60% in patients over 70 years of age. CONCLUSION: Alteration of some of the domains studied was proportional to evolution of POAG. This degradation can have physical, psychological and social impacts on his patients.

INTRODUCTION: La qualité de vie se définit par le bien-être physique, émotionnel et social d'un individu. Le Glaucome Primitif à Angle Ouvert (GPAO) est une neuropathie optique cécitante, il peut modifier la qualité de vie de par son caractère chronique et irréversible. L'objectif de cette étude était d'évaluer la qualité de vie chez les patients atteints de GPAO en milieu urbain. PATIENTS ET MÉTHODES: il s'agissait d'une étude quantitative transversale à visée descriptive sur 3 mois. Les patients suivis pour GPAO au CHU-IOTA avec un âge ≥ 18 ans ont été inclus et soumis au questionnaire GlauQOL-17 pour la collecte des données. RÉSULTATS: Nous avons colligé 100 patients glaucomateux, la moyenne d'âge des patients était de 52 ans avec un écart type de 14,02. Les extrêmes d'âges sont de 18 et 81 ans. Il y avait une prédominance masculine ; (54%) avec un sex-ratio (M/F) de 1.7. Les acuités visuelles bonnes étaient majoritaires (supérieures ou égales à 3/10).Parmi nos patients 35% étaient au stade de glaucome débutant à OD et 30% au stade de glaucome modéré à OG. Nos patients avaient un mauvais score qualité de vie (score < à 50%) dans les dimensions Anxiété et conduite. Chez les patients de moins de 70 ans nous avons noté un mauvais score d'anxiété dans tous les stades évolutifs de la maladie. Les scores des dimensions image de soi, contraintes, et prise en charge étaient supérieurs à 60% chez les patients de plus de 70 ans. CONCLUSION: L'altération de certains domaines étudiés était proportionnelle à l'évolution du GPAO. Cette dégradation peut avoir des impacts physiques, psychologiques et sociaux sur ses patients.

Gonococcal ophthalmia neonatorum: a case report.

A baby born at home 14 hours earlier was brought to the neonatology department with bilateral upper palpebral chemosis with purulent secretions and pseudomembranes, with no general signs of infection. The gram staining of a secretion sample shows the presence of Neisseria gonorrhoeae. Intramuscular ceftriaxone treatment was initiated, combined with topical application of rifamycin, dexamethasone, and oxytetracycline. Complete healing without sequelae was obtained after two weeks. This case presents an opportunity to review this preventable pathology and its treatment. The only effective way to prevent it is to raise the awareness of disadvantaged population about the value of antenatal care.

Stable multi-GeV electron accelerator driven by waveform-controlled PW laser pulses.

The achievable energy and the stability of accelerated electron beams have been the most critical issues in laser wakefield acceleration. As laser propagation, plasma wave formation and electron acceleration are highly nonlinear processes, the laser wakefield acceleration (LWFA) is extremely sensitive to initial experimental conditions. We propose a simple and elegant waveform control method for the LWFA process to enhance the performance of a laser electron accelerator by applying a fully optical and programmable technique to control the chirp of PW laser pulses. We found sensitive dependence of energy and stability of electron beams on the spectral phase of laser pulses and obtained stable 2-GeV electron beams from a 1-cm gas cell of helium. The waveform control technique for LWFA would prompt practical applications of centimeter-scale GeV-electron accelerators to a compact radiation sources in the x-ray and γ-ray regions.

Note: Real-time monitoring via second-harmonic interferometry of a flow gas cell for laser wakefield acceleration.

The use of a gas cell as a target for laser wakefield acceleration (LWFA) offers the possibility to obtain stable and manageable laser-plasma interaction process, a mandatory condition for practical applications of this emerging technique, especially in multi-stage accelerators. In order to obtain full control of the gas particle number density in the interaction region, thus allowing for a long term stable and manageable LWFA, real-time monitoring is necessary. In fact, the ideal gas law cannot be used to estimate the particle density inside the flow cell based on the preset backing pressure and the room temperature because the gas flow depends on several factors like tubing, regulators, and valves in the gas supply system, as well as vacuum chamber volume and vacuum pump speed/throughput. Here, second-harmonic interferometry is applied to measure the particle number density inside a flow gas cell designed for LWFA. The results demonstrate that real-time monitoring is achieved and that using low backing pressure gas (<1 bar) and different cell orifice diameters (<2 mm) it is possible to finely tune the number density up to the 10(19) cm(-3) range well suited for LWFA.

Detailed Experimental Study of Ion Acceleration by Interaction of an Ultra-Short Intense Laser with an Underdense Plasma.

Ion acceleration from intense (Iλ(2) > 10(18) Wcm(-2) µm(2)) laser-plasma interaction is experimentally studied within a wide range of He gas densities. Focusing an ultrashort pulse (duration ion plasma period) on a newly designed submillimetric gas jet system, enabled us to inhibit total evacuation of electrons from the central propagation channel reducing the radial ion acceleration associated with ponderomotive Coulomb explosion, a mechanism predominant in the long pulse scenario. New ion acceleration mechanism have been unveiled in this regime leading to non-Maxwellian quasi monoenergetic features in the ion energy spectra. The emitted nonthermal ion bunches show a new scaling of the ion peak energy with plasma density. The scaling identified in this new regime differs from previously reported studies.

[Medication adherence of 65 patients in hemodialysis in Togo]. / Observance médicamenteuse chez des hémodialysés au Togo. Étude monocentrique chez soixante-cinq sujets.

OBJECTIVE: The aim of this study was to assess adherence in people on hemodialysis and determine the factors of poor adherence. MATERIAL AND METHODS: This cross-sectional study took place throughout the month of September, 2012, in the hemodialysis center of the Sylvanus Olympio University Hospital, the only such center in Togo. RESULTS: The study included 65 patients, with a mean age of 49.5 years (range: 22 to 77 years), more often men (sex ratio: 1.82) and married (74 %). More than half (58%) had completed secondary education, while 73% belonged to the least advantaged socioeconomic class; 61 (94%) had health insurance, and 57% had been on dialysis for 1 to 4 years. The compliance rate was 11%. The main factors associated with good adherence were marital status (p = 0.0339) and the patient's general health status (p = 0.001). Treatment fatigue (p = 0.0347), forgetfulness (p = 0.0001), dosage forms and drug characteristics (p = 0.0198) were all factors of noncompliance. Therapeutic non-compliance was proportional to the number of drugs prescribed (p = 0.4263). CONCLUSION: Adherence in hemodialysis patients in Togo is very poor.

[Epidemiology and prognosis of childhood cancers at Gabriel-Touré Teaching Hospital (Bamako, Mali)]. / Épidémiologie et pronostic des cancers pédiatriques au CHU Gabriel-Touré de Bamako (Mali).

UNLABELLED: Cancer today is being treated as a public health problem in Africa, as in developed countries. OBJECTIVE: The aim of this retrospective study was to evaluate the epidemiology and outcome of children treated in the Pediatric Oncology Unit of Gabriel Touré Teaching Hospital in Bamako (Mali), six years after it opened. METHODS: Retrospective study of the files of all children aged 15 and younger diagnosed with cancer and treated by chemotherapy between January 1, 2005, and December 31, 2010. RESULTS: The study included 690 children. Their mean age was 24 months. The time from observation of first symptoms to consultation was less than 3 months in 200 cases (29%), from 3 to 10 months in 256 (37.1%), and more than 10 months in 234 (33.9%). The five most common childhood cancers were malignant non-Hodgkin's lymphoma (NHL) (n=231, 33.5%), retinoblastoma (n=170, 24.6%), nephroblastoma (n=102, 14.8%), acute lymphoblastic leukemia (n=54, 7%), and Hodgkin's disease (n=34, 4%). Six years after the unit opened and after a mean follow-up of 3 years, we recorded 272 deaths (39.4%); at least 238 children are still alive (34.5%), with 180 cases (26.1%) lost to follow-up. CONCLUSION: Childhood cancer survival is still low in Mali, and the rate of loss to follow-up quite high.

Short intense laser pulse collapse in near-critical plasma.

It is observed that the interaction of an intense ultrashort laser pulse with a near-critical gas jet results in the pulse collapse and the deposition of a significant fraction of the energy. This deposition happens in a small and well-localized volume in the rising part of the gas jet, where the electrons are efficiently accelerated and heated. A collisionless plasma expansion over ~ 150 µm at a subrelativistic velocity (~ c/3) has been optically monitored in time and space, and attributed to the quasistatic field ionization of the gas associated with the hot electron current. Numerical simulations in good agreement with the observations suggest the acceleration in the collapse region of relativistic electrons, along with the excitation of a sizable magnetic dipole that sustains the electron current over several picoseconds.

Comparative anatomy of the hind limb vessels of the bearded capuchins (Sapajus libidinosus) with apes, baboons, and Cebus capucinus: with comments on the vessels' role in bipedalism.

Capuchin monkeys are known to exhibit sporadic bipedalism while performing specific tasks, such as cracking nuts. The bipedal posture and locomotion cause an increase in the metabolic cost and therefore increased blood supply to lower limbs is necessary. Here, we present a detailed anatomical description of the capuchin arteries and veins of the pelvic limb of Sapajus libidinosus in comparison with other primates. The arterial pattern of the bearded capuchin hind limb is more similar to other quadrupedal Cebus species. Similarities were also found to the pattern observed in the quadruped Papio, which is probably due to a comparable pelvis and the presence of the tail. Sapajus' traits show fewer similarities when compared to great apes and modern humans. Moreover, the bearded capuchin showed unique patterns for the femoral and the short saphenous veins. Although this species switches easily from quadrupedal to bipedal postures, our results indicate that the bearded capuchin has no specific or differential features that support extended bipedal posture and locomotion. Thus, the explanation for the behavioral differences found among capuchin genera probably includes other aspects of their physiology.

Anticorrelation between ion acceleration and nonlinear coherent structures from laser-underdense plasma interaction.

In laser-plasma experiments, we observed that ion acceleration from the Coulomb explosion of the plasma channel bored by the laser is prevented when multiple plasma instabilities, such as filamentation and hosing, and nonlinear coherent structures (vortices or postsolitons) appear in the wake of an ultrashort laser pulse. The tailoring of the longitudinal plasma density ramp allows us to control the onset of these instabilities. We deduced that the laser pulse is depleted into these structures in our conditions, when a plasma at about 10% of the critical density exhibits a gradient on the order of 250 µm (Gaussian fit), thus hindering the acceleration. A promising experimental setup with a long pulse is demonstrated enabling the excitation of an isolated coherent structure for polarimetric measurements and, in further perspectives, parametric studies of ion plasma acceleration efficiency.

Development and characterization of very dense submillimetric gas jets for laser-plasma interaction.

We report on the characterization of recently developed submillimetric He gas jets with peak density higher than 10(21) atoms/cm(3) from cylindrical and slightly conical nozzles of throat diameter of less than 400 µm. Helium gas at pressure 300-400 bar has been developed for this purpose to compensate the nozzle throat diameter reduction that affects the output mass flow rate. The fast-switching electro-valve enables to operate the jet safely for multi-stage vacuum pump assembly. Such gaseous thin targets are particularly suitable for laser-plasma interaction studies in the unexplored near-critical regime.

Dependence on pulse duration and foil thickness in high-contrast-laser proton acceleration.

Experimental measurements of proton acceleration with high intensity and high-contrast short laser pulses have been carried out over an order of magnitude range in target thickness and laser pulse duration. The dependence of the maximum proton energy with these parameters is qualitatively supported by two-dimensional particle-in-cell simulations. They evidence that two regimes of proton acceleration can take place, depending on the ratio between the density gradient and the hot electron Debye length at the rear target surface. As this ratio can be affected by the target thickness, a complex interplay between pulse duration and target thickness is observed. Measurements and simulations support unexpected variations in the laser absorption and hot electron temperature with the pulse duration and laser intensity, for which density profile modification at the target front surface is the controlling parameter.