Astrogliosis and compensatory neurogenesis after the first ethanol binge drinking-like exposure in the adolescent rat

BACKGROUND

Multiple ethanol binge drinking-like exposures during adolescence in the rat induce neuroinflammation, loss of neurogenesis, and cognitive deficits in adulthood. Interestingly, the first ethanol binge drinking-like exposure during adolescence also induces short- term impairments in cognition and synaptic plasticity in the hippocampus though the cellular mechanisms of these effects are unclear. Here, we sought to determine which of the cellular effects of ethanol might play a role in the disturbances in cognition and synaptic plasticity observed in the adolescent male rat after two binge-like ethanol exposures.

METHODS

Using immunochemistry, we measured neurogenesis, neuronal loss, astrogliosis, neuroinflammation, and synaptogenesis in the hippocampus of adolescent rats 48 h after two binge-like ethanol exposures (3 g/kg, i.p., 9 h apart). We used flow cytometry to analyze activated microglia and identify the TLR4-expressing cell types.

RESULTS

We detected increased hippocampal doublecortin immunoreactivity in the subgranular zone (SGZ) of the dentate gyrus (DG), astrogliosis in the SGZ, and a reduced number of mature neurons in the DG and in CA3, suggesting compensatory neurogenesis. Synaptic density decreased in the stratum oriens of CA1 revealing structural plasticity. There was no change in microglial TLR4 expression or in the number of activated microglia, suggesting a lack of neuroinflammatory processes, although neuronal TLR4 was decreased in CA1 and DG.

CONCLUSIONS

Our findings demonstrate that the cognitive deficits associated with hippocampal synaptic plasticity alterations that we previously characterized 48 h after the first binge-like ethanol exposures are associated with hippocampal structural plasticity, astrogliosis, and decreased neuronal TLR4 expression, but not with microglia reactivity.

Impact du nombre d’interventions infirmières sur la durée d’administration des catécholamines chez les patients de réanimation : étude INTERVAL

Objectifs : Bien que quotidiennement géré par les infirmier(ière)s diplômé(e)s d’État (IDE) de réanimation, le sevrage des catécholamines a rarement été étudié. L’hypothèse de notre étude était que l’augmentation du nombre d’interventions menées sur la vitesse de perfusion des catécholamines permettait de raccourcir la durée d’administration de celles-ci.

Patients et méthodes : Il s’agissait d’une étude prospective observationnelle dans 21 réanimations. Tous les patients traités par vasopresseurs pendant la période d’étude ont été inclus. Le nombre d’interventions effectuées par l’IDE en charge du patient sur la vitesse d’administration des catécholamines était noté toutes les quatre heures. La posologie de catécholamines en cours ainsi que la pression artérielle moyenne (PAM) du patient étaient également relevées. Les facteurs influençant la rapidité du sevrage des catécholamines étaient également analysés.

Résultats : Nous avons inclus 226 patients dont l’âge moyen était de 65 ± 14 ans. La durée moyenne du traitement par catécholamines était de 71,6 (±81) heures. Le nombre d’interventions IDE par quatre heures était de 1,9 (±2,8) intervention. La durée du traitement par catécholamines était significativement moindre lorsque le nombre d’interventions augmentait (p = 0,04). L’existence d’un protocole spécifique à la gestion des catécholamines raccourcissait leur durée de sevrage. Un IGS2 élevé, une PAM élevée ainsi que la période diurne étaient associés à une augmentation du nombre des interventions IDE.

Conclusion : Le nombre d’interventions par les IDEs menées sur la perfusion de catécholamines était inversement lié à la durée du traitement par catécholamines. Des études complémentaires permettront d’évaluer l’impact de ces interventions sur le pronostic des patients.

Signaling lymphocytic activation molecules Slam and cancers: friends or foes?

Signaling Lymphocytic Activation Molecules (SLAM) family receptors are initially described in immune cells. These receptors recruit both activating and inhibitory SH2 domain containing proteins through their Immunoreceptor Tyrosine based Switch Motifs (ITSMs). Accumulating evidence suggest that the members of this family are intimately involved in different physiological and pathophysiological events such as regulation of immune responses and entry pathways of certain viruses. Recently, other functions of SLAM, principally in the pathophysiology of neoplastic transformations have also been deciphered. These new findings may prompt SLAM to be considered as new tumor markers, diagnostic tools or potential therapeutic targets for controlling the tumor progression. In this review, we summarize the major observations describing the implications and features of SLAM in oncology and discuss the therapeutic potential attributed to these molecules.

RB/PLK1-dependent induced pathway by SLAMF3 expression inhibits mitosis and control hepatocarcinoma cell proliferation

Polo-like kinase PLK1 is a cell cycle protein that plays multiple roles in promoting cell cycle progression. Among the many roles, the most prominent role of PLK1 is to regulate the mitotic spindle formation checkpoint at the M-phase. Recently we reported the expression of SLAMF3 in Hepatocytes and show that it is down regulated in tumor cells of hepatocellular carcinoma (HCC). We also show that the forced high expression level of SLAMF3 in HCC cells controls proliferation by inhibiting the MAPK ERK/JNK and the mTOR pathways. In the present study, we provide evidence that the inhibitory effect of SLAMF3 on HCC proliferation occurs through Retinoblastoma (RB) factor and PLK1-dependent pathway. In addition to the inhibition of MAPK ERK/JNK and the mTOR pathways, expression of SLAMF3 in HCC retains RB factor in its hypophosphorylated active form, which in turn inactivates E2F transcription factor, thereby repressing the expression and activation of PLK1. A clear inverse correlation was also observed between SLAMF3 and PLK expression in patients with HCC. In conclusion, the results presented here suggest that the tumor suppressor potential of SLAMF3 occurs through activation of RB that represses PLK1. We propose that the induction of a high expression level of SLAMF3 in cancerous cells could control cellular mitosis and block tumor progression.

Safe and prolonged survival with long-term exposure to pomalidomide in relapsed/refractory myeloma

BACKGROUND

The IFM2009-02 trial studied pomalidomide (4 mg daily, 21/28 versus 28/28) and dexamethasone in very advanced relapsed or refractory multiple myeloma (RRMM). We observed that 40% of patients had a prolonged progression-free survival (PFS) and subsequently overall survival (OS). We sought to analyze the characteristics of these patients and study the effect of long exposure to pomalidomide.

DESIGN

We separated the studied population into two groups: 3 months to 1 year (<1 year) and more than 1 year (≥1 year) of treatment with pomalidomide and dexamethasone based on clinical judgment and historical control studies. We then analyzed the characteristics of patients according to duration of treatment.

RESULTS

The overall response rate (ORR) for the <1-year group was 43%, the median PFS 4.6 months [95% confidence interval (95% CI) 3.8-6.4] with only 6% at 12 months, and the median OS was 15 months (11.7-20.3) and 40% at 18 months. For the ≥1-year group, the response rate and survival were strikingly different, ORR at 83%, median PFS 20.7 months (14.7-35.4), median OS not reached, and 91% at 18 months.

CONCLUSION

Pomalidomide and dexamethasone favored prolonged and safe exposure to treatment in 40% of heavily treated and end-stage RRMM, a paradigm shift in the natural history of RRMM characterized with a succession of shorter disease-free intervals and ultimately shorter survival. Although an optimization of pomalidomide-dexamethasone regimen is warranted in advanced RRMM, we claim that pomalidomide has proven once more to change the natural history of myeloma in this series, which should be confirmed in a larger study.

[Pomalidomide for multiple myeloma]

Once characterized by a very poor outcome, multiple myeloma (MM) now has a significantly prolonged survival, with major improvements allowed by the use of "novel agents": proteasome inhibitors (first-in-class bortezomib) and immunomodulatory compounds (IMiDs; first-in-class thalidomide and lenalidomide). However, the vast majority - if not all - of patients with MM ultimately end up being refractory to all existing drugs, including these efficient novel agents. There is a clear unmet medical need in this situation, which warrants the development of the next generation of proteasome inhibitors and IMiDs, as well as new drug classes. This review focuses on pomalidomide, the next generation IMiD, recently approved by the US FDA and the EMA for patients with relapsed or refractory MM who have received at least two prior therapies, including lenalidomide and bortezomib, and have demonstrated disease progression on their last therapy.

[Smoldering multiple myeloma]

Smoldering multiple myeloma (SMM) is an asymptomatic plasma cell neoplasia, characterized by monoclonal plasma cell proliferation in the absence of end-organ damage, but with a high risk of progression to multiple myeloma. It has therefore to be distinguished from monoclonal gammapathy of undetermined significance (MGUS), which has a much lower risk of progression, but also from multiple myeloma, which remains an incurable disease and requires a specific treatment. The critical question in the management of SMM is whether an early therapeutic strategy could help delaying the progression to multiple myeloma, in order to lower the risk of serious complications related to this progression, or even to cure the disease. This early treatment could not be proposed to all SMM patients, who are indeed asymptomatic, and in whom the risk of toxicity could make it difficult to justify the potential benefit obtained. The challenge is to target early at diagnosis SMM patients with a high risk of progression, using available routine tests sufficiently reliable to warrant the therapeutic sanction which relies on it. Today however, apart from randomized studies, recommendations are to maintain therapeutic abstention in SMM patients.

Effect of streptozotocin-induced diabetes mellitus on release of vasoactive intestinal polypeptide from rodent small intestine

Representative longitudinal muscle strips (6 x 10 mm) from proximal and distal small intestine were excised from control and streptozotocin-treated rats after one month of untreated and insulin-treated diabetes. Untreated diabetes significantly reduced tissue concentrations of vasoactive intestinal polypeptide (VIP) at both intestinal loci. Insulin treatment of the diabetic animals restored tissue VIP concentrations to control group levels, although the beneficial effect of insulin treatment was only significant in the duodenum. Spontaneous release of VIP was significantly attenuated by untreated diabetes at both intestinal sites. In the duodenum, insulin treatment of the diabetic animals restored VIP release to levels indistinguishable from control group values. In the ileum, insulin treatment produced levels of VIP release that were not significantly different from those of the control and untreated diabetic groups. Tetrodotoxin (5 x 10(-6) M) significantly--but incompletely--inhibited VIP release from control group animals at both intestinal sites. These observations indicate that diabetes mellitus significantly diminishes VIP tissue concentrations and release from intestinal myenteric nerves. These abnormalities improve with insulin treatment. However, the mechanisms of VIP release from proximal and distal intestine appear to differ not only in their response to the diabetic state, but also in their response to insulin treatment.