Excessive CNS synapses are eliminated during development to establish mature patterns of neuronal connectivity. A complement cascade protein, C1q, is involved in this process. Mice deficient in C1q fail to refine retinogeniculate connections resulting in excessive retinal innervation of lateral geniculate neurons. We hypothesized that C1q knockout (KO) mice would exhibit defects in neocortical synapse elimination resulting in enhanced excitatory synaptic connectivity and epileptiform activity. We recorded spontaneous and evoked field potential activity in neocortical slices and obtained video-EEG recordings from implanted C1q KO and wild-type (WT) mice. We also used laser scanning photostimulation of caged glutamate and whole cell recordings to map excitatory and inhibitory synaptic connectivity. Spontaneous and evoked epileptiform field potentials occurred at multiple sites in neocortical slices from C1q KO, but not WT mice. Laser mapping experiments in C1q KO slices showed that the proportion of glutamate uncaging sites from which excitatory postsynaptic currents (EPSCs) could be evoked ("hotspot ratio") increased significantly in layer IV and layer V, although EPSC amplitudes were unaltered. Density of axonal boutons was significantly increased in layer V pyramidal neurons of C1q KO mice. Implanted KO mice had frequent behavioral seizures consisting of behavioral arrest associated with bihemispheric spikes and slow wave activity lasting from 5 to 30 s. Results indicate that epileptogenesis in C1q KO mice is related to a genetically determined failure to prune excessive excitatory synapses during development. complement cascade | seizure | synaptic pruning | development | axonal boutons E arly brain development is marked by an exuberant outgrowth of axons that innervate multiple targets. These projections are later refined through axonal pruning, a developmental regulatory process by which excessive connectivity is eliminated and mature patterns of neuronal innervation become established (1). Cortical synaptic pruning events, such as selective branch elimination for segregating layer V cortical neuronal projections to subcortical targets (1), and refinement of interhemispheric (2) and intracortical (3) are important for the development of precisely wired connections and normal information processing. The activation of a number of genes and proteins is crucial for the process of synaptic pruning in the mammalian brain (4). Recently, molecules ordinarily associated with immune and inflammatory processes have been shown to play nonimmune roles in synaptic pruning (5). C1q and C3 genes of the classical complement cascade are necessary for synapse elimination in the retino-geniculate pathway during development (6). Activation of C1q protein by astrocytes leads to triggering of a protease cascade, deposition of C3 and opsonization or "tagging" of synapses that are likely eliminated by microglia. Lateral geniculate relay neurons in C1q knockout (KO) mice deficient in these proteins retain multiple synaptic contacts f...

A number of isatin sulfonamide analogues were prepared and their potencies for inhibiting caspase-1, -3, -6, -7, and -8 were evaluated in vitro. Several compounds displaying a nanomolar potency for inhibiting the executioner caspases, caspase-3 and caspase-7, were identified. These compounds were also observed to have a low potency for inhibiting the initiator caspases, caspase-1 and caspase-8, and caspase-6. Molecular modeling studies provided further insight into the interaction of this class of compounds with activated caspase-3. The results of the current study revealed a number of non-peptide-based caspase inhibitors that may be useful in assessing the role of inhibiting the executioner caspases in minimizing tissue damage in disease conditions characterized by unregulated apoptosis.

Background: Adverse drug outcomes in the elderly have led to the development of lists of potentially inappropriate medications (PIMs), such as the Beers criteria, and these PIMs have been studied widely; however, it is still unclear whether PIM use is predictive of adverse outcomes in older people. Objective: To qualitatively examine the associations between exposure to PIMs from the general Beers criteria and the Screening Tool of Older Persons’ Prescriptions list and adverse outcomes, such as adverse drug reactions (ADRs)/adverse drug events (ADEs), hospitalization, and mortality. Methods: Specified databases were searched from inception to February 1, 2018. Two reviewers independently selected studies that met the inclusion criteria, assessed study quality, and extracted data. Data were pooled using Stata 12.0. The outcomes were ADRs/ADEs, hospitalization, and mortality. Results: A total of 33 studies met the inclusion criteria. The combined analysis revealed a statistically significant association between ADRs/hospitalizations and PIMs (odds ratio [OR] = 1.44, 95% CI = 1.33-1.56; OR = 1.27, 95% CI = 1.20-1.35), but no statistically significant association was found between mortality and PIMs (OR = 1.04; 95% CI = 0.75-1.45). It is interesting to note that the results changed when different continents/criteria were used for the analysis. Compared with the elderly individuals exposed to 1 PIM, the risk of adverse health outcomes was much higher for those who took ≥2 PIMs. Conclusion and Relevance: We recommend that clinicians avoid prescribing PIMs for older adults whenever feasible. In addition, the observed associations should be generalized to other countries with different PIM criteria with caution.

ObjectivesToll-like receptors (TLRs) are important initiators in native immune responses to microbial infections. TLR4 is up-regulated in response to H.pylori infection in gastric epithelial cells. However, the regulatory mechanisms for the expression of TLR4 in H.pylori infection have not been clearly defined. The aims of this study are to present the evidence that microRNA let-7b directly regulates TLR4 expression in human gastric epithelial cells, and subsequently influences the activation of NF-κB and the expression of the downstream genes in H.pylori infection.MethodsThe expression of let-7b was determined in gastric mucosa specimens and in two gastric epithelial cell lines using quantitative RT-PCR. The expression of TLR4 was determined by immunohistochemistry staining and RT-PCR. The potential target of let-7b was identified by luciferase reporter assay and Western blot. Let-7b mimics and inhibitors were used to examine the effects of let-7b on NF-κB activity. The expression of the downstream genes of NF-κB was also determined in cells infected with H.pylori 26695.ResultsLet-7b was significantly decreased in gastric mucosa specimens and in gastric epithelial cell lines (AGS, GES-1) infected with H.pylori 26695 (cagA+). Let-7b was complementary to the 3′-UTR of TLR4 mRNA and regulated TLR4 expression via post-transcriptional suppression in gastric epithelium. Infection of H.pylori induced the expression of TLR4 and activated NF-κB in AGS and GES-1 cells. Overexpression of let-7b by mimics downregulated TLR4, and subsequently attenuated NF-κB, MyD88, NF-κB1/p50, RelA/p65. The expression of IL-8, COX-2 and CyclinD1 was inhibited in H.pylori infected cells with let-7b overexpression. Both TAK-242 (TLR4 inhibitor) and SN50 (NF-κB inhibitor) significantly inhibited the H.pylori induced downregulation of let-7b.ConclusionsLet-7b targets at TLR4 mRNA, and regulates the activation of NF-κB and the expression of the downstream genes related to the inflammation and immune responses in H.pylori infection.

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