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1.
J Opt Soc Am A Opt Image Sci Vis ; 38(8): 1237-1247, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-34613319

RESUMEN

This work reports the 3D reconstruction of a particle from a set of three simulated interferometric images of this particle (from three perpendicular angles of view). The reconstruction of each view from its corresponding interferometric pattern uses the error-reduction (ER) algorithm. The 3D reconstruction enables an estimation of the volume of the particle. The method is tested on a dendrite-like particle. An experimental demonstration of the technique is done using a digital micromirror device (DMD) that generates the interferometric images of "programmable" rough particles.

2.
IDCases ; 26: e01249, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34466386

RESUMEN

Campylobacter fetus causes in humans mostly gastroenteritis. Systemic infection occurs almost exclusively in immunocompromised patients with chronic debilitating diseases. We report the case of a Campylobacter fetus meningitis in a woman aged 48 years with a history of systemic lupus erythematosus treated with corticosteroids and immunosuppressive drugs. Cerebrospinal fluid culture was positive for Campylobacter fetus. The evolution was favorable using imipenem and ciprofloxacin.

3.
Artículo en Inglés | MEDLINE | ID: mdl-33188405

RESUMEN

The purpose of this study was to establish the diagnostic reference levels (DRLs) for paediatric head computed tomography (CT) in Morocco and to assess the effective doses received during head CT examinations. The data of 1007 patients were collected retrospectively from Moroccan university children's hospitals. The sample was classified per age group:<1, 1-5, 5-10 and 10-15 years. The proposed DRLs were defined as 75th percentile of the distributions, which were in terms of CT dose index of 26.98, 28.88, 34.00 and 38.20 mGy and dose length product of 461.64, 540.06, 627.20 and 705.98 mGy.cm, respectively. The effective doses estimated were 3.6, 2.9, 2 and 1.79 mSv, respectively. The DRLs reported in Morocco were compared with those of other countries, which were based on the same age grouping method, including Thailand, Switzerland, Japan and the international DRLs. Our initiative via the determination of the first Moroccan diagnostic reference levels for paediatric head CT must be a starting point to spread this investigation towards other examinations and imaging modalities.

4.
J Fr Ophtalmol ; 42(7): 746-752, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31208910

RESUMEN

The authors report their experience with the use of Integra® dermal substitute, in combination with a thin skin graft, following an orbital exenteration. The clinical case described relates to a 42-year-old gentleman with an ulcerative retractile lesion of the right lower eyelid. Histopathological examination diagnosed a moderately differentiated epidermoid carcinoma infiltrating the orbit. Total exenteration was necessary as well as secondary radiation therapy and chemotherapy. Rehabilitation of the exenterated socket was performed by inserting an Integra® patch, followed by an additional thin skin graft one month later. The authors review the various available techniques for exenterations, their indications and the various possible secondary rehabilitations. Despite being less utilized, the dermal substitute technique, which is relatively new, seems to offer quicker and easier rehabilitation compared to traditional techniques. A comparative study would be necessary to define superiority among the different techniques of exenteration, with respect to the speed of rehabilitation and resistance to radiation therapy.


Asunto(s)
Carcinoma de Células Escamosas/cirugía , Evisceración Orbitaria/métodos , Neoplasias Orbitales/cirugía , Procedimientos de Cirugía Plástica/métodos , Trasplante de Piel , Piel Artificial , Adulto , Carcinoma de Células Escamosas/patología , Neoplasias del Ojo/cirugía , Párpados/cirugía , Humanos , Masculino , Órbita/cirugía , Colgajos Quirúrgicos
5.
Rev Sci Instrum ; 90(5): 053109, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31153261

RESUMEN

The characterization of ice crystals has important applications in airborne research and civil aviation. Interferometric out-of-focus imaging is a promising technique. We investigate in this study the impact of the 3D shape reconstruction of the particles from a pair of interferometric images on the estimation of the ice particle's volume. An interferometric image gives indeed the 2D autocorrelation of the particle's shape. As different shapes can exhibit a similar 2D autocorrelation, particles of different shapes can have similar interferometric images. In this study, the volume of ice particles is estimated from a pair of interferometric images (with two perpendicular angles of view). The relative error in the particle's volume estimation is shown to be around ΔV V≈30% depending on the choice of the initial 3D particle's shape. It appears that the choice of the shape of the particle for both angles of view has a lower impact on the estimation of the particle's volume than the other sources of errors due to image acquisitions themselves.

6.
Appl Opt ; 57(21): 6188-6197, 2018 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-30117999

RESUMEN

Interferometric particle imaging enables particle size estimation in a wide range [from 10 µm to a few millimeters] depending on the optical system design. With a multi-view optical system, it is possible to extract more information about the 3D morphology of the particle. In this study, multi-view interferometric out-of-focus imaging of ice particles is performed in a backward-scattering configuration. It is used to estimate ice particle volume and thus to reduce uncertainty concerning particle size estimation. It is further used to better analyze the presence of nearby particles whose images overlap.

7.
Mediterr J Hematol Infect Dis ; 9(1): e2017062, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29181139

RESUMEN

INTRODUCTION: In a developing country like Algeria, such expensive therapy is not available. Alternative approaches are needed to help these adult. In Algeria 'imatib' (CIPLA-India) was introduced in 2006; but no study has been published yet in the North Africa region regarding response and outcome of this copy in CML patients. The goal of this multicenter study is to characterize newly adult CML in the western region of Algeria and to assess the effectiveness and safety of imatib (IM, copy) as frontline therapy for patients with CML. PATIENTS AND METHODS: The study was carried out in 7 hematology centers in the western Algeria. Patients, who were diagnosed to be suffering from CML between January 1st, 2007 and December 31st, 2014 were selected for data analysis. All patients received a copy preparation, consisting of the alpha crystal form of imatinib, (IM, copy) at an oral dose of 400 mg daily and monitored for tolerance and side effects while on therapy. RESULTS: Between January 2007 and December 2014, 355 patients with CML were treated with imatib (Copy). The median follow- up of the study was 46 months (range: 13-107 months). Complete hematological response (CHR) was seen in 83% of patients within 3 months. According to the Sokal score, 72% patients with low, 78% with intermediate and 69% with high risk disease achieved a CHR in 3 months (p=0.26) and according to the EUTOS score, 81% of patients with low and 70% with high risk disease achieved a CHR in 3 months (p=0.08). The major molecular response (MMR) at six months (M6), M9, M12, M18 and M24 was 21%, 38%, 35%, 51% and 67% respectively and 34% of patients achieved a complete molecular response (CMR). The projected 5-year overall survival (OS) rate was 83%. Side effects of imatib (copy) in this study were similar to those reported previously for the entire imatinib mesylate treatment study and only 8% of patients were intolerant to imatib (copy) and treated with a second generation of BCR-ABL inhibitor. CONCLUSION: This study reflects real world experience treating patients with CML in a developing country and thus sheds light on differences in this population compared to Western countries. In conclusion, imatib (copy) is effective and safe in treating patients with CML in chronic phase and proves to have a durable outcome. To our knowledge this is the first study reporting the response to imatib (copy) in an Algerian population.

8.
Rev Sci Instrum ; 88(8): 083108, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28863671

RESUMEN

Airborne characterization of ice crystals has important applications. The extreme difficulty of realizing in situ tests requires the development of a complete instrumentation in the laboratory. Such an installation should enable design, development, test, and calibration of instruments in conditions as close as possible to real ones. We present a set of numerical and experimental tools that have been developed to realize ice crystal sensors based on interferometric particle imaging. The set of tools covers the development of complementary simulators for crystal growth and interferometric particle imaging predictions, experimental generation of "programmable" ice crystals, and instrumentation of a freezing column where different techniques as in-focus imaging, out-of-focus imaging, and digital in-line holography can be combined simultaneously for test and calibration.

9.
J Mycol Med ; 27(2): 139-145, 2017 Jun.
Artículo en Francés | MEDLINE | ID: mdl-28342778

RESUMEN

In Algeria, superficial mycoses are very commonly diagnosed. Deep fungal infections are less often observed. Few data from Algeria are found in the literature. We report for the first time the main causes of these diseases in our country and provide burden estimates. We searched for existing data and estimated the incidence and prevalence of fungal diseases based on the population at risk and available epidemiological data. Demographic data were derived from the Service (Office) of the Statistics (ONES), World Health Organization (WHO), The Joint Nations Programme on HIV/AIDS (UNAIDS) and national published reports. When no data existed, risk populations were used to estimate frequencies of fungal infections, using previously described methodology. Algeria has 40.4 million inhabitants and probably at least 568,900 (1.41 %) of Algerians have a serious fungal infection each year. Recurrent vulvovaginal candidiasis (485,000) and fungal asthma (72,000) are probably the commonest problems as there are over 1 million adult asthmatics. Candidaemia is estimated in 2020, invasive aspergillosis in 2865, intra-abdominal candidiasis in 303 people and are the most common life-threatening problems. AIDS is uncommon, but cancer is not (45,000 new cases of cancer among including 1500 in children) and nor is COPD (an estimated 317,762 patients of whom 20.3 % are admitted to hospital each year). A focus on improving the diagnosis and epidemiological data related to fungal infection is necessary in Algeria.


Asunto(s)
Micosis/epidemiología , Adulto , Argelia/epidemiología , Niño , Femenino , Humanos , Masculino , Prevalencia
10.
Eur J Clin Microbiol Infect Dis ; 36(6): 999-1004, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28220323

RESUMEN

We report for the first time in Algeria and provide burden estimates. We searched for existing data and estimated the incidence and prevalence of fungal diseases based on the population at risk and available epidemiological data. Demographic data were derived from the National Office of Statistics (Office National des Statistiques: ONS), World Health Organization (WHO), The Joint Nations Programme on HIV/AIDS (UNAIDS) and national published reports. When no data existed, risk populations were used to estimate frequencies of fungal infections, using previously described methodology. Algeria has 40.4 million inhabitants, and probably at least 568,900 (1.41%) of Algerians have a serious fungal infection each year. Recurrent vulvovaginal candidiasis (485,000) and fungal asthma (72,000) are probably the commonest problems, as there are over 1 million adult asthmatics. Candidaemia is estimated in 2,020 people, invasive aspergillosis in 2,865 people, and intra-abdominal candidiasis in 303 people; these are the most common life-threatening problems. AIDS is uncommon, but cancer is not (45,000 new cases of cancer including 1,500 in children), nor is COPD (an estimated 317,762 patients, of whom 20.3% are admitted to hospital each year). A focus on improving the diagnosis and epidemiological data related to fungal infection is necessary in Algeria.


Asunto(s)
Micosis/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Argelia/epidemiología , Niño , Preescolar , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Prevalencia , Adulto Joven
11.
Appl Opt ; 55(32): 9154-9159, 2016 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-27857308

RESUMEN

We realize simplified-tomography experiments on irregular rough particles using interferometric out-of-focus imaging. Using two angles of view, we determine the global 3D-shape, the dimensions, and the 3D-orientation of irregular rough particles whose morphologies belong to families such as sticks, plates, and crosses.

13.
Drug Test Anal ; 4(12): 1014-27, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22615163

RESUMEN

An innovative versatile strategy using Total Error has been proposed to decide about the method's validity that controls the risk of accepting an unsuitable assay together with the ability to predict the reliability of future results. This strategy is based on the simultaneous combination of systematic (bias) and random (imprecision) error of analytical methods. Using validation standards, both types of error are combined through the use of a prediction interval or ß-expectation tolerance interval. Finally, an accuracy profile is built by connecting, on one hand all the upper tolerance limits, and on the other hand all the lower tolerance limits. This profile combined with pre-specified acceptance limits allows the evaluation of the validity of any quantitative analytical method and thus their fitness for their intended purpose. In this work, the approach of accuracy profile was evaluated on several types of analytical methods encountered in the pharmaceutical industrial field and also covering different pharmaceutical matrices. The four studied examples depicted the flexibility and applicability of this approach for different matrices ranging from tablets to syrups, different techniques such as liquid chromatography, or UV spectrophotometry, and for different categories of assays commonly encountered in the pharmaceutical industry i.e. content assays, dissolution assays, and quantitative impurity assays. The accuracy profile approach assesses the fitness of purpose of these methods for their future routine application. It also allows the selection of the most suitable calibration curve, the adequate evaluation of a potential matrix effect and propose efficient solution and the correct definition of the limits of quantification of the studied analytical procedures.


Asunto(s)
Modelos Estadísticos , Preparaciones Farmacéuticas/análisis , Tecnología Farmacéutica/métodos , Amoxicilina/análisis , Sesgo , Calibración , Química Farmacéutica , Cromatografía Líquida de Alta Presión , Formas de Dosificación , Contaminación de Medicamentos , Fluconazol/análisis , Límite de Detección , Modelos Lineales , Metformina/análisis , Parabenos/análisis , Estándares de Referencia , Reproducibilidad de los Resultados , Espectrofotometría Ultravioleta , Tecnología Farmacéutica/normas
14.
Anal Chim Acta ; 714: 47-56, 2012 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-22244136

RESUMEN

Analytical methods capability evaluation can be a useful methodology to assess the fitness of purpose of these methods for their future routine application. However, care on how to compute the capability indices have to be made. Indeed, the commonly used formulas to compute capability indices such as Cpk, will highly overestimate the true capability of the methods. Especially during methods validation or transfer, there are only few experiments performed and, using in these situations the commonly applied capability indices to declare a method as valid or as transferable to a receiving laboratory will conduct to inadequate decisions. In this work, an improved capability index, namely Cpk-tol and the corresponding estimator of proportion of non-conforming results (π(Cpk-tol)) have been proposed. Through Monte-Carlo simulations, they have been shown to greatly increase the estimation of analytical methods capability in particular in low sample size situations as encountered during methods validation or transfer. Additionally, the usefulness of this capability index has been illustrated through several case studies covering applications commonly encountered in the pharmaceutical industry. Finally a methodology to determine the optimal sample size required to validate analytical methods is also given using the proposed capability metric.


Asunto(s)
Técnicas de Química Analítica/métodos , Técnicas de Química Analítica/normas , Preparaciones Farmacéuticas/análisis , Estudios de Validación como Asunto , Acetazolamida/análisis , Cromatografía Liquida/métodos , Simulación por Computador , Industria Farmacéutica/métodos , Industria Farmacéutica/normas , Industria Farmacéutica/tendencias , Fluconazol/análisis , Método de Montecarlo , Reproducibilidad de los Resultados , Comprimidos/química
15.
J Pharm Biomed Anal ; 55(3): 583-90, 2011 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-21377822

RESUMEN

Analytical methods validation is a mandatory step to evaluate the ability of developed methods to provide accurate results for their routine application. Validation usually involves validation standards or quality control samples that are prepared in placebo or reconstituted matrix made of a mixture of all the ingredients composing the drug product except the active substance or the analyte under investigation. However, one of the main concerns that can be made with this approach is that it may lack an important source of variability that come from the manufacturing process. The question that remains at the end of the validation step is about the transferability of the quantitative performance from validation standards to real authentic drug product samples. In this work, this topic is investigated through three case studies. Three analytical methods were validated using the commonly spiked placebo validation standards at several concentration levels as well as using samples coming from authentic batch samples (tablets and syrups). The results showed that, depending on the type of response function used as calibration curve, there were various degrees of differences in the results accuracy obtained with the two types of samples. Nonetheless the use of spiked placebo validation standards was showed to mimic relatively well the quantitative behaviour of the analytical methods with authentic batch samples. Adding these authentic batch samples into the validation design may help the analyst to select and confirm the most fit for purpose calibration curve and thus increase the accuracy and reliability of the results generated by the method in routine application.


Asunto(s)
Preparaciones Farmacéuticas/análisis , Preparaciones Farmacéuticas/normas , Placebos/análisis , Placebos/normas , Calibración , Química Farmacéutica , Cromatografía Líquida de Alta Presión/instrumentación , Cromatografía Líquida de Alta Presión/métodos , Hidroclorotiazida/análisis , Hidroclorotiazida/normas , Metformina/análisis , Metformina/normas , Parabenos/análisis , Parabenos/normas , Control de Calidad , Estándares de Referencia , Reproducibilidad de los Resultados , Espectrofotometría Ultravioleta/instrumentación , Espectrofotometría Ultravioleta/métodos , Comprimidos , Tetrazoles/análisis , Tetrazoles/normas , Valina/análogos & derivados , Valina/análisis , Valina/normas , Valsartán
16.
Rev Neurol (Paris) ; 166(8-9): 721-6, 2010.
Artículo en Francés | MEDLINE | ID: mdl-20299068

RESUMEN

INTRODUCTION: During the month of Ramadan, Muslims fast every day from dawn to sunset. Several studies have shown that Ramadan fasting affects biochemical parameters, sleep/wake cycle, behaviour and food habits. The purpose of the study was to evaluate the effect of Ramadan fasting (RF) and physical exercise on cognitive functions, blood glucose. METHODS: Eleven healthy male volunteers aged 20.45+/-1.65 years were assessed before RF (B.RF), during the 1st week (wk), 3rd wk and 1 wk B.RF, in blood sugar, work memory (WM), visual perception (VP), before exercise (B. Ex) and after exercise (A. Ex) exercise of 1000 m. RESULTS: Compared to control days (B.RF), there were no significant changes in body mass index. Physical performance declined significantly during 1st wk (p<0.001), 3th wk (p<0.013) and before (p<0.046) of RF. At the level of the glycemia, the results show a significant effect of Ramadan by increasing gradually during Ramadan but nevertheless, the values remain lower of 100mg/dl. No significant change was observed between B. Ex and A. Ex value in WM during RF. However, the WM A. Ex value increase significantly during and after RF (respectively 1st wk (p<0.013), 3rd wk (p<0.005) and before (p<0.003). The VP was significantly affected by fasting effect (F=16.84, p<0.001) and exercise effect (F=14.01, p<0.0001), and was progressively increased 15.56% in the 1st wk, 25.69%, the 3rd wk during RF, and 27.07% A.RF, but no significant change was found in errors performances of VP during and after RF. CONCLUSION: These results showed that the intermittent fasting imply differently effects on cognitive functions and physiological.


Asunto(s)
Glucemia/análisis , Cognición/fisiología , Ejercicio Físico/fisiología , Ayuno/fisiología , Ritmo Circadiano/fisiología , Ayuno/efectos adversos , Humanos , Islamismo , Masculino , Memoria a Corto Plazo/fisiología , Desempeño Psicomotor , Deportes , Percepción Visual , Adulto Joven
17.
J Chromatogr A ; 1217(19): 3180-92, 2010 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-19733857

RESUMEN

Analytical method validation is a mandatory step at the end of the development in all analytical laboratories. It is a highly regulated step of the life cycle of a quantitative analytical method. However, even if some documents have been published there is a lack of clear guidance for the methodology to follow to adequately decide when a method can be considered as valid. This situation has led to the availability of several methodological approaches and it is therefore the responsibility of the analyst to choose the best one. The classical decision processes encountered during method validation evaluation are compared, namely the descriptive, difference and equivalence approaches. Furthermore a validation approach using accuracy profile computed by means of beta-expectation tolerance interval and total measurement error is also available. In the present paper all of these different validation approaches were applied to the validation of two analytical methods. The evaluation of the producer and consumer risks by Monte Carlo simulations were also made in order to compare the appropriateness of these various approaches. The classical methodologies give rise to inadequate and contradictory conclusions which do not allow them to answer adequately the objective of method validation, i.e. to give enough guarantees that each of the future results that will be generated by the method during routine use will be close enough to the true value. It is found that the validation methodology which gives the most guarantees with regards to the reliability or adequacy of the decision to consider a method as valid is the one based on the use of the accuracy profile.


Asunto(s)
Química Analítica , Modelos Estadísticos , Acetaminofén/análisis , Calibración , Cromatografía Liquida/métodos , Codeína/análisis , Simulación por Computador , Modelos Lineales , Loratadina/análisis , Reproducibilidad de los Resultados , Proyectos de Investigación , Estudios de Validación como Asunto
18.
Comput Methods Programs Biomed ; 94(3): 223-31, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19215994

RESUMEN

This paper deals with the discrimination of premature ventricular contraction (PVC) arrhythmia using the fractal behavior of the power spectrum density of the QRS complexes. The linear interpolation of the QRS complex power spectrum density in Bode diagram in two different frequency intervals gives two straight lines with two different slopes. The scatter plot of one slope versus the other shows that there exists two distinct regions which represent the normal beats and the PVC beats. Therefore the PVC beats are classified using a self-organizing map fed by the two slopes of the QRS complex power spectrum. The MIT/BIH arrhythmia database is then used to evaluate the usefulness of the proposed method in the discrimination of the premature ventricular contraction (PVC) arrhythmia. The results have indicated that the method has achieved 82.71% of sensitivity and 88.06% of specificity over 46 records from the MIT-BIH arrhythmia database.


Asunto(s)
Arritmias Cardíacas/diagnóstico , Electrocardiografía/métodos , Procesamiento de Señales Asistido por Computador , Complejos Prematuros Ventriculares/diagnóstico , Algoritmos , Arritmias Cardíacas/fisiopatología , Inteligencia Artificial , Automatización/métodos , Cardiología/instrumentación , Cardiología/métodos , Biología Computacional/métodos , Humanos , Modelos Estadísticos , Reconocimiento de Normas Patrones Automatizadas/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Complejos Prematuros Ventriculares/fisiopatología
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