Effective removal of paracetamol in compound parabolic collectors and fixed bed reactors under natural sunlight.

Removal of persistent organic pollutants from water is quite challenging using biological treatment processes in waste water treatment plants. In order to improve the wastewater treatment quality for water reuse, many techniques are developed and the most commonly used is heterogeneous photocatalysis. This work studies the degradation of paracetamol (PAR), which is one of the most persistent pharmaceutical drugs in water, and widely used as an analgesic and antipyretic drug in Algeria. The paracetamol degradation has been carried out via heterogeneous photocatalysis, in a suspended solution of catalyst using a Compound Parabolic Collectors (CPC) reactor and in a fixed bed with immobilized catalyst under natural solar radiation. The degradation performance has been studied under various parameters such as substrate concentration and pH of solution. The degradation efficiency decreased when the initial paracetamol concentration increased from 2.5 mg/L to 20 mg/L. In addition, the selected reactors were found to be competent for the paracetamol degradation with an almost 98-99% removal of PAR. For the CPC reactor with suspended TiO2, the paracetamol elimination reached 98% after 300 min; however, for the fixed-bed reactor, TiO2 immobilized on cellulose-based paper was utilized, which yielded an almost 99% reduction in the PAR concentration after 90 min only of solar irradiation.

Isolation and identification of mycobacteria responsible for tuberculosis of dromedaries in Algeria. / Isolement et identification de mycobactéries responsables de la tuberculose du dromadaire en Algérie.

Tuberculosis in dromedaries in Algeria has been little studied to date. The purpose of this study is to determine the prevalence of tuberculosis in dromedaries in three Algerian slaughterhouses using samples from suspected tuberculosis lesions, which were detected on carcasses during a post-mortem visual inspection. The study also uses laboratory diagnosis to isolate and identify the agents responsible for the infection. Between 2016 and 2018, 102 carcasses (3.05%; with a confidence interval [CI] of 95% from 2.05 to 3.69) were suspected of tuberculosis out of a total of 3,342 dromedary carcasses inspected. The lesions were located as follows in the carcasses: 64 of 102 were in the lungs, 37 in the liver and 1 in a bronchial ganglion. Five and six samples respectively of suspected tuberculosis lesions were found to be positive by bacilloscopy (4.9%; with a CI of 95% from 1.61 to 11.1) and in culture (5.88%; with a CI of 95% from 2.19 to 12.36). The concordance between bacilloscopy and culture was good (kappa coefficient of 0.71) and the probability of finding a positive culture was 184 times greater when the bacilloscopy was positive (value of p = 0.01). Molecular characterisation by polymerase chain reaction of extracts of DNA gave a positive signal, indicating that the isolated strains belonged to a mycobacterium genus. An enzymatic restriction on DNA extracts indicated the presence of mycobacterium DNA belonging to the Mycobacterium tuberculosis complex. Spoligotyping on the same DNA extracts confirmed the presence of four strains of Mycobacterium bovis with the same spoligotype SB0941 and another strain with spoligotype SB2562, a newly described profile in this study, which is phylogenetically close to the previous profile. Using suspected tuberculosis lesions in dromedaries, a non-tuberculosis mycobacterium was identified as Mycobacterium virginiense MO-233 (sequence ID: Nr149186) using the sequencing technique on the region 16SrDNA. Having demonstrated the presence of tuberculosis with M. bovis in the Algerian dromedary population, it is now necessary to implement measures to control it in order to reduce transmission between animals and humans.

À ce jour, la tuberculose a été peu étudiée chez les camélidés en Algérie. L'objectif de cette étude est de déterminer la prévalence de la tuberculose cameline dans trois abattoirs algériens à partir de prélèvements de lésions suspectes de cette maladie qui ont été détectées sur des carcasses lors de l'examen à l'inspection visuelle post-mortem. L'étude vise aussi à isoler et à identifier les agents responsables de cette infection par un diagnostic de laboratoire. Durant la période de 2016 à 2018, 102 carcasses (3,05 % ; avec un intervalle de confiance [IC] à 95 % de 2,05 à 3,69) ont été déclarées suspectes de tuberculose sur un total de 3 342 carcasses de dromadaires inspectées. Concernant la localisation des lésions sur ces 102 carcasses, 64 présentaient des lésions aux poumons, 37 au niveau du foie et 1 dans un ganglion bronchique. Respectivement cinq et six échantillons de lésions suspectes de tuberculose cameline ont été trouvés positifs à la bacilloscopie (4,90 % ; avec un IC à 95 % de 1,61 à 11,10) et en culture (5,88 % ; avec un IC à 95 % de 2,19 à 12,36). La concordance entre la bacilloscopie et la culture était bonne (coefficient kappa de 0,71) et la probabilité de trouver une culture positive était 184 fois plus élevée lorsque la bacilloscopie était positive (valeur de p = 0,01). La caractérisation moléculaire par réaction de polymérisation en chaîne (PCR) des extraits d'ADN a montré un signal positif, signifiant que les souches isolées appartenaient au genre mycobactérien. Une restriction enzymatique réalisée sur des extraits d'ADN a indiqué la présence d'ADN d'une mycobactérie appartenant au complexe Mycobacterium tuberculosis. Une technique de spoligotypage réalisée sur les mêmes extraits d'ADN a permis de confirmer la présence de quatre souches de Mycobacterium bovis avec un même spoligotype SB0941 et d'une autre souche avec un spoligotype SB2562, un profil nouvellement décrit dans cette étude et qui est phylogénétiquement proche du profil précédent. Au départ de lésions suspectes de tuberculose chez le dromadaire, une souche de mycobactérie non tuberculeuse a été identifiée comme étant un Mycobacterium virginiense MO-233 (séquence ID : Nr149186) par la technique de séquençage de la région 16SrDNA. La présence de la tuberculose à M. bovis ayant été démontrée dans la population cameline algérienne, il est dès lors nécessaire de mettre en oeuvre des mesures visant à la contrôler en vue de réduire la transmission entre l'animal et l'homme.

A día de hoy, la tuberculosis está poco estudiada en los camélidos de Argelia. Los autores presentan un estudio encaminado a determinar la prevalencia de la tuberculosis de los camélidos en tres mataderos argelinos a partir de muestras de lesiones sospechosas, detectadas en las canales durante la inspección visual post-mortem. El estudio consistía pues en aislar e identificar, mediante técnicas de diagnóstico de laboratorio, a los agentes responsables de la infección. Entre 2016 y 2018, de un total de 3 342 canales de dromedarios inspeccionadas, 102 fueron declaradas sospechosas de tuberculosis (un 3,05%; intervalo de confianza [IC] del 95%: 2,05-3,69). En cuanto a la localización de las lesiones, en 64 de los 102 animales, estas se encontraban en los pulmones, en 37 de los 102 en la región del hígado y 1 de los animales presentaba una lesión en un ganglio bronquial. De las muestras de lesiones sospechosas de tuberculosis de los camélidos, cinco resultaron positivas por baciloscopia (un 4,90%; IC del 95%: 1,61-11,10) y seis en cultivo (un 5,88%; IC del 95%: 2,19-12,36). Entre la baciloscopia y el cultivo hubo una estrecha concordancia (coeficiente kappa: 0,71) y la probabilidad de encontrar un cultivo positivo fue 184 veces mayor cuando la baciloscopia era positiva (p = 0,01). La caracterización molecular de extractos de ácido desoxirribonucleico (ADN) por reacción en cadena de la polimerasa (PCR) deparó una señal positiva, lo que significa que las cepas aisladas pertenecían al género Mycobacterium. La aplicación de una técnica de restricción enzimática a extractos de ADN puso de relieve la presencia de ADN de una micobacteria perteneciente al complejo Mycobacterium tuberculosis. Aplicando una técnica de espoligotipificación a los mismos extractos de ADN se pudo confirmar la presencia de cuatro cepas de Mycobacterium bovis con un mismo espoligotipo, SB0941, y de otra cepa con el espoligotipo SB2562, patrón nuevo y filogenéticamente cercano al anterior que se describe aquí por primera vez. A partir de lesiones sospechosas de tuberculosis detectadas en dromedarios se pudo caracterizar una cepa de micobacteria no tuberculosa, identificada como Mycobacterium virginiense MO-233 (secuencia ID: Nr149186), con la técnica de secuenciación de la región 16S rDNA. Habiendo quedado demostrada la presencia de tuberculosis por M. bovis en la población de camélidos argelina, se impone la necesidad de implantar medidas para controlarla, a fin de reducir la transmisión entre los animales y el ser humano.

Progressive atrophy of cerebellar Purkinje cell dendrites during aging of the heterozygous staggerer mouse (Rora(+/sg)).

Staggerer (Rora(sg/sg)) is an autosomal mutation in an orphan nuclear hormone receptor gene, RORalpha, that acts intrinsically within the Purkinje cells and causes dysgenesis of the cerebellar cortex. Purkinje cell number is severely reduced, and the surviving cells are small with poorly developed dendrites. In contrast, the cytoarchitecture of the cerebellar cortex of the heterozygous staggerer (Rora(+/sg)) appears to be normal. However, quantitative studies have revealed a premature loss of Purkinje cells with advancing age. Most of the loss (25--30%) is complete by 13 months with little change thereafter. To address the question of whether all Purkinje cells, even the surviving ones, are affected by aging even though their cell bodies remain intact, we studied the evolution with age of the dendritic arbor through a semi-quantitative analysis of Golgi-impregnated Purkinje cells. A total of ten different morphological parameters were measured in 4-, 12- and 22-month-old wild type and heterozygous Rora(+/sg) mice. While the effects of the aging process are apparent in the wild type cerebellum, they are considerably accelerated in the Rora(+/sg) mouse. By 12 months the Rora(+/sg) Purkinje cell dendrite is as atrophic as a wild type dendrite from a 22-month-old and the dendritic regression continues well beyond the period of cell death in the heterozygous Rora(+/sg) mouse.

Hypothyroidism prolongs mitotic activity in the post-natal mouse brain.

Circulating T(4) and T(3) were measured during the first three post-natal weeks in the mouse and found to increase in a triphasic manner. The first increase occurred at post-natal day 6 and was simultaneous with a decrease in bromodeoxyuridine incorporation in areas showing post-natal mitosis. We investigated whether there was a causal relationship between increased thyroid hormone levels and decreased proliferation by inducing hypothyroidism in dams and progeny. Hypothyroidism prolonged mitotic activity in the olfactory bulb, hippocampus, subventricular zone and the cerebellar cortex. This suggests that the increase in T(3) at the end of the first postnatal week is implicated in terminating progenitor proliferation in many parts of the mouse brain.

Cerebellar Purkinje cell loss during life span of the heterozygous staggerer mouse (Rora(+)/Rora(sg)) is gender-related.

The staggerer mutation causes dysgenesis of the cerebellar cortex in the homozygous mutant (Rora(sg)/Rora(sg)). The mutation acts intrinsically within the Purkinje cells (PCs), leading to cytological abnormalities and a severe deficit in the number of these cells. In contrast, in the heterozygous staggerer (Rora(+)/Rora(sg)), the cytoarchitecture of the cerebellar cortex appears to be normal, but quantitative studies have revealed a significant loss of cerebellar neurons with advancing age. In the heterozygous reeler (+/rl), another mutant presenting a PC loss with age, we have found that only males were affected (Hadj-Sahraoui et al., 1996). In the present study, we have investigated whether a similar gender effect exists in the heterozygous staggerer during life span. PCs were counted on cerebellar sagittal sections in male and female Rora(+)/Rora(sg) and in their Rora(+)/Rora(+) littermates at 1, 3, 9, 13, 18, and 24 months of age. In the Rora(+)/Rora(+), the number of PCs remained stable until 18 months, but there was a 25% significant loss in 24- month-old mice of both genders. During life span, Rora(+)/Rora(+) males had slightly more PC than females. In the Rora(+)/Rora(sg) of both genders, the deficit in PC number was similar at 13 months but it appeared earlier in males, beginning between 1 and 3 months, and was aggravated regularly up to 13 months. By contrast, the decline was delayed and more abrupt in Rora(+)/Rora(sg) females, from a value still normal at 9 months to its maximal extent at 13 months. In view of these results, the heterozygous (Rora(+)/Rora(sg)) mouse offers an interesting model to test the interaction between sex, age, and genetic background on the development and maintenance of cerebellar neuronal populations.

Thyroid hormone effects on Krox-24 transcription in the post-natal mouse brain are developmentally regulated but are not correlated with mitosis.

Krox-24 (NGFI-A, Egr-1) is an immediate-early gene encoding a zinc finger transcription factor. As Krox-24 is expressed in brain areas showing post-natal neurogenesis during a thyroid hormone (T3)-sensitive period, we followed T3 effects on Krox-24 expression in newborn mice. We analysed whether regulation was associated with changes in mitotic activity in the subventricular zone and the cerebellum. In vivo T3-dependent Krox-24 transcription was studied by polyethylenimine-based gene transfer. T3 increased transcription from the Krox-24 promoter in both areas studied at post-natal day 2, but was without effect at day 6. An intact thyroid hormone response element (TRE) in the Krox-24 promoter was necessary for these inductions. These stage-dependent effects were also seen in endogenous Krox-24 mRNA levels: activation at day 2 and no effect at day 6. Moreover, similar results were obtained by examining beta-galactosidase expression in heterozygous mice in which one allele of the Krox-24 gene was disrupted with an inframe Lac-Z insertion. However, bromodeoxyuridine incorporation showed mitosis to continue through to day 6. We conclude first, that T3 activates Krox-24 transcription during early post-natal mitosis but that this effect is extinguished as development proceeds and second, loss of T3-dependent Krox-24 expression is not correlated with loss of mitotic activity.

Purkinje cell loss in heterozygous staggerer mutant mice during aging.

The cerebellum on the heterozygous (+/sg) staggerer mutant mouse has recently been proposed as a model system in which to study the genetic contribution to the normal process of central nervous system aging since there is significant loss of neurons from 3 to 12 months of age (Shojaeian-Zanjani, H., Mariani, J., Delhaye-Bouchaud, N., and Herrup, K. (1992) Dev. Brain Res., 67, 153-160). In the current study we extend our analysis of the changes in Purkinje cell numbers up to 24 months of age in +/sg and C57BL/6J wild-type mice. At 13 and 18 months, while wild-type Purkinje cell numbers remain unchanged, there is a 22-26% loss in the number of Purkinje cells in +/sg after which no further cell loss is observed. Between 18 and 24 months, however, a 22% loss of Purkinje cell occurs in +/+ animals, with the result that by 2 years of age, the size of the Purkinje cell population is again similar in both genotypes. Analysis of the cell loss in both the mediolateral and the anteroposterior dimensions, as well as the immunostaining of Purkinje cells in frontal sections, reveal no obvious regional variation in the Purkinje cell loss. These results suggest that in +/sg, a precocious process of aging affects the size of the Purkinje cell population.

Gender effect on Purkinje cell loss in the cerebellum of the heterozygous reeler mouse.

Homozygous mutant mice such as staggerer (sg/sg) or reeler (rl/rl) exhibit a marked ataxia associated with an atrophic cerebellum during the first postnatal weeks and a reduced number of Purkinje cells, the deficit reaching about 75% in sg/sg and 50% in rl/rl as compared to age- and sex-matched mice from the same strain background. These two mutations are classically viewed as recessive, but we have recently shown that heterozygous staggerer (+/sg) mice exhibit a progressive and age-related loss of Purkinje cells between 3 and 12 months of age, despite their apparent clinical normality (Shojaeian-Zanjani et al., 1992). In the present study, we have investigated whether a similar cell loss exists in the cerebellum of heterozygous +/rl mice. The number of Purkinje cells was counted in serial parasagittal sections of the cerebellum of +/rl and their +/+ littermates at 3, 16 and 26 months of age. Our results reveal a 16% deficit in the number of Purkinje cells in 3-month-old +/rl and a 24% one in 16-month-old animals: surprisingly this deficit is only present in the +/rl males, while the females are spared. These results suggest that the reeler gene (D'Arcangelo et al., 1995) exerts its effect on Purkinje cell number in a gender-specific fashion in heterozygous mutant mice.