Effet du chrome niacinate sur la tolérance au glucose chez le rat wistar

Le chrome est un oligoélément essentiel à l’homéostasie du métabolisme glucidique qui pourrait également être impliqué dans l’étiologie de l’athérosclérose. Trois lots de rats Wistar males (n= 30, âgé de 2 mois) traités quotidiennement et pendant 28 jours. Les Contrôles ont reçu du sérum physiologique (1µL/g/j, ip), groupe II a reçu la dexaméthasone (DEX : 0,2 mg/kg/j, ip) et les rats du groupe III ont reçu le même régime que le groupe II avec une supplémentation en CrN à partir du 7 ème jour de l’expérimentation (CrN : 30 mg/kg/j, PO). A la fin de l’expérimentation, les rats sont sacrifiés et les paramètres biochimiques sont dosés. Les résultats montrent une augmentation du poids corporel des rats témoins par apport aux groupes traités par la DEX. La supplémentation en CrN n’a pas corrigé l’élévation de la glycémie et de l’insulinémie engendré par la DEX, de même l’ajout du CrN n’influe pas sur la variation des taux de la triglycéridémie et de la cholestérolémie entrainés par la DEX. Il est notamment observé que l’addition du CrN n’a pas d’effet notable sur la fonction hépatique et la fonction rénale.Mots-clés : chrome, diabète, glycémie, dexaméthasone.Effect of chromium niacinate on glucose tolerance at wistar rat Chromium is an essential trace element in the homeostasis of glucose metabolism could also be involved in the etiology of atherosclerosis. Three groups of male Wistar rats (n= 30, age 2 months) treated daily for 28 days. Controls received saline (1µl/g/day, ip), group II received dexamethasone (DEX: 0, 2 mg/kg/day, ip) and the rats of group III received the same treatment as the group II with supplementation CrN from the 7 day of the experiment (CrN: 30 mg/kg/day, PO). At the end of the experiment, the rats were sacrificed and biochemical parameters were measured. The results show an increase in the body weight of control rats contribution to the DEX treated groups. CrN supplementation did not correct the elevation of blood glucose and insulin caused by DEX. The addition of CrN does not affect the rate of change in triglycerides and cholesterol trained by DEX. It is particularly noted that the addition of CrN has no significant effect on liver and kidney functions.Keywords : chromium, diabetes, glucose, dexamethasone

Ramadan fasting influences on food intake consumption, sleep schedule, body weight and some plasma parameters in healthy fasting volunteers

This study examines the changes in the lifestyle that accompanied Ramadan fasting. For this purpose, we followed the questionnaire programming meals, food consumption and sleep rhythm. We also followed changes in plasma biological parameters. The results show that daily energy consumption was not changed and neither was the body weight. Nevertheless, a decrease in fat mass was detected. Concerning plasma, we found a decrease in blood glucose from the 7th day of fasting. This effect was found also at the 21st day, accompanied by a reduction in insulin levels. Our results on plasma lipids showed a decrease in triglycerides with total cholesterol level unchanged. Furthermore, we noted an increased HDL-C against a decreased LDL-C fraction. Taken together, these results suggest that fasting may induce beneficial effects in blood lipid concentrations.Keywords: Ramadan fasting, food intake consumption, sleep schedule, body weight, plasma parameters, healthy fasting volunteersAfrican Journal of Biotechnology Vol. 12(21), pp. 3327-333

Efecto de procesos de ahumado frío y caliente y la adición de extracto polifenólico natural de Dunaliella salina sobre la calidad bioquímica y la vida útil de filetes de Sander lucioperca almacenados durante 90 días

The effects of cold and hot smoking and the addition of Dunaliella salina polyphenol extract on the biochemical quality and shelf-life of Sander lucioperca fillets after storage for 90 days at 0-4 °C were examined. The results showed a significant increase in protein, lipid, free fatty acid, and 1,1-diphenyl-2-picrylhydrazyl contents, and a decrease in peroxide and thiobarbituric acid reactive substances, and volatile base nitrogen levels in cold (CSF) and hot (HSF) smoked fillets covered with or without extract and stored for 1, 20, and 90 days compared to fresh fillets (FF). Saturated and monounsaturated fatty acids exhibited a significant increase in FF and CSF and HSF covered with or without extract. The total polyunsaturated fatty acids revealed a significant decrease in FF and CSF and HSF with or without extract. Therefore, cold and hot smoking and polyphenol extract improved the biochemical quality and storage shelf-life of fillets for 90 days at 0-4 °C.Se examinaron los efectos del ahumado en frío y en caliente y la adición de extracto de polifenoles de Dunaliella salina sobre la calidad bioquímica y la vida útil de filetes de Sander lucioperca almacenados durante 90 días a 0-4 °C. Los resultados mostraron un aumento significativo en los contenidos de proteínas, lípidos, ácidos grasos libres y 1,1-difenil-2-picrilhidrazilo, y una disminución en las sustancias reactivas de peróxido y ácido tiobarbitúrico, y los niveles de nitrógeno básico volátil en frío (LCR) y caliente (HSF) de filetes ahumados cubiertos con o sin extracto y almacenados durante 1, 20 y 90 días en comparación con los filetes frescos (FF). Los ácidos grasos saturados y monoinsaturados exhibieron un aumento significativo en FF y LCR y HSF cubiertos con o sin extracto. Los ácidos grasos poliinsaturados totales revelaron una disminución significativa en FF y CSF y HSF con o sin extracto. Por lo tanto, el ahumado en frío y en caliente y el extracto de polifenoles mejoraron la calidad bioquímica y la vida útil durante el almacenamiento de los filetes durante 90 días a 0-4 °C

Composición bioquímica y potencial antioxidante del pepino del mar Mediterráneo comestible Holothuria tubulosa

The sea cucumber or holothurian is a marine species which has been prized in some Asian coun­tries for its nutritional qualities. The purpose of this work was to study the biochemical composition and free radical scavenging and antioxidant activities of Holothuria tubulosa tegument from the Bizerta lagoon in north­ern Tunisia. The obtained data demonstrated that the extract of sea cucumber teguments exhibited high bio­chemical levels (such as moisture 80.77%, protein 7.07%, lipids 10.21%, energy value 13.64 Kcal/g ww), and an important nutritional value (including n-3/n-6: 2.11, EPA+DHA: 20.96, AI: 1.38 and TI: 0.54). High anti­oxidant activities were recorded in the integument by the radical scavenging tests of ABTS and DPPH as well as by the total antioxidant capacity and the FRAP in comparison with the BHT standard. Our results showed that H. Tubulosa tegument has high nutritional value with high antioxidant activities and could be considered a nutraceutical product.El pepino de mar o la holoturia es una especie marina apreciada en algunos países asiáti­cos por sus cualidades nutricionales. El propósito de este trabajo fue estudiar la composición bioquímica y las actividades antioxidantes y de eliminación de radicales libres del tegumento de Holothuria tubulosa de la laguna de Bizerta, en el norte de Túnez. Los datos obtenidos demuestran que el extracto de tegumentos de pepino de mar mostró altos niveles bioquímicos (como humedad 80,77%, proteína 7,07%, lípidos 10,21%, valor energético 13,64 Kcal/gww) y un valor nutricional importante (incluyendo n-3/ n-6: 2,11, EPA+DHA: 20,96, AI: 1,38 y TI: 0,54). Se registraron altas actividades antioxidantes en el tegumento mediante las pruebas de eliminación de radicales de ABTS y DPPH, así como por la capacidad antioxidante total y el FRAP, y esto, en comparación con el estándar BHT. Nuestros resultados mostraron que el tegumento de H. Tubulosa tiene un valor nutricional importante con una alta actividad antioxidante y podría considerarse un producto nutracéutico

Effect of recipient age on prioritisation for liver transplantation in the UK:a population-based modelling study

BACKGROUND: Following the introduction of an algorithm aiming to maximise life-years gained from liver transplantation in the UK (the transplant benefit score [TBS]), donor livers were redirected from younger to older patients, mortality rate equalised across the age range and short-term waiting list mortality reduced. Understanding age-related prioritisation has been challenging, especially for younger patients and clinicians allocating non-TBS-directed livers. We aimed to assess age-related prioritisation within the TBS algorithm by modelling liver transplantation prioritisation based on data from a UK transplant unit and comparing these data with other regions.METHODS: In this population-based modelling study, serum parameters and age at liver transplantation assessment of patients attending the Scottish Liver Transplant Unit, Edinburgh, UK, between December, 2002, and November, 2023, were combined with representative synthetic data to model TBS survival predictions, which were compared according to age group (25-49 years vs ≥60 years), chronic liver disease severity, and disease cause. Models for end-stage liver disease (UKELD [UK], MELD [Eurotransplant region], and MELD 3.0 [USA]) were used as validated comparators of liver disease severity.FINDINGS: Of 2093 patients with chronic liver disease, 1808 (86%) had complete datasets and liver disease parameters consistent with eligibility for the liver transplant waiting list in the UK (UKELD ≥49). Disease severity as assessed by UKELD, MELD, and MELD 3.0 did not differ by age (median UKELD scores of 56 for patients aged ≥60 years vs 56 for patients aged 25-49 years; MELD scores of 16 vs 16; and MELD 3.0 scores of 18 vs 18). TBS increased with advancing age (R=0·45, p&lt;0·0001). TBS predicted that transplantation in patients aged 60 years or older would provide a two-fold greater net benefit at 5 years than in patients aged 25-49 years (median TBS 1317 [IQR 1116-1436] in older patients vs 706 [411-1095] in younger patients; p&lt;0·0001). Older patients were predicted to have shorter survival without transplantation than younger patients (263 days [IQR 144-473] in older patients vs 861 days [448-1164] in younger patients; p&lt;0·0001) but similar survival after transplantation (1599 days [1563-1628] vs 1573 days [1525-1614]; p&lt;0·0001). Older patients could reach a TBS for which a liver offer was likely below minimum criteria for transplantation (UKELD &lt;49), whereas many younger patients were required to have high-urgent disease (UKELD &gt;60). US and Eurotransplant programmes did not prioritise according to age.INTERPRETATION: The UK liver allocation algorithm prioritises older patients for transplantation by predicting that advancing age increases the benefit from liver transplantation. Restricted follow-up and biases in waiting list data might limit the accuracy of these benefit predictions. Measures beyond overall waiting list mortality are required to fully capture the benefits of liver transplantation.FUNDING: None.</p

miR-504 modulates the stemness and mesenchymal transition of glioma stem cells and their interaction with microglia via delivery by extracellular vesicles

Glioblastoma (GBM) is a highly aggressive tumor with poor prognosis. A small subpopulation of glioma stem cells (GSCs) has been implicated in radiation resistance and tumor recurrence. In this study we analyzed the expression of miRNAs associated with the functions of GSCs using miRNA microarray analysis of these cells compared with human neural stem cells. These analyses identified gene clusters associated with glioma cell invasiveness, axonal guidance, and TGF-β signaling. miR-504 was significantly downregulated in GSCs compared with NSCs, its expression was lower in GBM compared with normal brain specimens and further decreased in the mesenchymal glioma subtype. Overexpression of miR-504 in GSCs inhibited their self-renewal, migration and the expression of mesenchymal markers. The inhibitory effect of miR-504 was mediated by targeting Grb10 expression which acts as an oncogene in GSCs and GBM. Overexpression of exogenous miR-504 resulted also in its delivery to cocultured microglia by GSC-secreted extracellular vesicles (EVs) and in the abrogation of the GSC-induced polarization of microglia to M2 subtype. Finally, miR-504 overexpression prolonged the survival of mice harboring GSC-derived xenografts and decreased tumor growth. In summary, we identified miRNAs and potential target networks that play a role in the stemness and mesenchymal transition of GSCs and the miR-504/Grb10 pathway as an important regulator of this process. Overexpression of miR-504 exerted antitumor effects in GSCs as well as bystander effects on the polarization of microglia via delivery by EVs

Healed Lesions of Human Cutaneous Leishmaniasis Caused By Leishmania major Do Not Shelter Persistent Residual Parasites

In human cutaneous leishmaniasis (HCL) caused by Leishmania (L.) major, the cutaneous lesions heal spontaneously and induce a Th1-type immunity that confers solid protection against reinfection. The same holds true for the experimental leishmaniasis induced by L. major in C57BL/6 mice where residual parasites persist after spontaneous clinical cure and induce sustainable memory immune responses and resistance to reinfection. Whether residual parasites also persist in scars of cured HCL caused by L. major is still unknown. Cutaneous scars from 53 volunteers with healed HCL caused by L. major were biopsied and the tissue sample homogenates were analyzed for residual parasites by four methods: i) microscope detection of amastigotes, ii) parasite culture by inoculation on biphasic medium, iii) inoculation of tissue exctracts to the footpad of BALB/c mice, an inbred strain highly susceptible to L. major, and iv) amplification of parasite kDNA by a highly sensitive real-time PCR (RT-PCR). Our results show that the scars of healed lesions of HCL caused by L. major do not contain detectable residual parasites, suggesting that this form likely induces a sterile cure at least within the scars. This feature contrasts with other Leishmania species causing chronic, diffuse, or recidivating forms of leishmaniasis where parasites do persist in healed lesions. The possibility that alternative mechanisms to parasite persistence are needed to boost and maintain long-term immunity to L. major, should be taken into consideration in vaccine development against L. major infection

UV activation of polymeric high aspect ratio microstructures: Ramifications in antibody surface loading for circulating tumor cell selection

The need to activate thermoplastic surfaces using robust and efficient methods has been driven by the fact that replication techniques can be used to produce microfluidic devices in a high production mode and at low cost, making polymer microfluidics invaluable for in vitro diagnostics, such as circulating tumor cell (CTC) analysis, where device disposability is critical to mitigate artifacts associated with sample carryover. Modifying the surface chemistry of thermoplastic devices through activation techniques can be used to increase the wettability of the surface or to produce functional scaffolds to allow for the covalent attachment of biologics, such as antibodies for CTC recognition. Extensive surface characterization tools were used to investigate UV activation of various surfaces to produce uniform and high surface coverage of functional groups, such as carboxylic acids in microchannels of different aspect ratios. We found that the efficiency of the UV activation process is highly dependent on the microchannel aspect ratio and the identity of the thermoplastic substrate. Colorimetric assays and fluorescence imaging of UV-activated microchannels following EDC/NHS coupling of Cy3-labeled oligonucleotides indicated that UV-activation of a PMMA microchannel with an aspect ratio of ???3 was significantly less efficient toward the bottom of the channel compared to the upper sections. This effect was a consequence of the bulk polymer&apos;s damping of the modifying UV radiation due to absorption artifacts. In contrast, this effect was less pronounced for COC. Moreover, we observed that after thermal fusion bonding of the device&apos;s cover plate to the substrate, many of the generated functional groups buried into the bulk rendering them inaccessible. The propensity of this surface reorganization was found to be higher for PMMA compared to COC. As an example of the effects of material and microchannel aspect ratios on device functionality, thermoplastic devices for the selection of CTCs from whole blood were evaluated, which required the immobilization of monoclonal antibodies to channel walls. From our results, we concluded the CTC yield and purity of isolated CTCs were dependent on the substrate material with COC producing the highest clinical yields for CTCs as well as better purities compared to PMMA.close9