Methamphetamine (METH) is abused worldwide, and it represents a threat for public health. METH exposure induces a variety of detrimental effects. In fact, METH produces a number of oxidative species, which lead to lipid peroxidation, protein misfolding, and nuclear damage. Cell clearing pathways such as ubiquitin-proteasome (UP) and autophagy (ATG) are involved in METH-induced oxidative damage. Although these pathways were traditionally considered to operate as separate metabolic systems, recent studies demonstrate their interconnection at the functional and biochemical level. Very recently, the convergence between UP and ATG was evidenced within a single organelle named autophagoproteasome (APP), which is suppressed by mTOR activation. In the present research study, the occurrence of APP during METH toxicity was analyzed. In fact, coimmunoprecipitation indicates a binding between LC3 and P20S particles, which also recruit p62 and alpha-synuclein. The amount of METH-induced toxicity correlates with APP levels. Specific markers for ATG and UP, such as LC3 and P20S in the cytosol, and within METH-induced vacuoles, were measured at different doses and time intervals following METH administration either alone or combined with mTOR modulators. Western blotting, coimmunoprecipitation, light microscopy, confocal microscopy, plain transmission electron microscopy, and immunogold staining were used to document the effects of mTOR modulation on METH toxicity and the merging of UP with ATG markers within APPs. METH-induced cell death is prevented by mTOR inhibition, while it is worsened by mTOR activation, which correlates with the amount of autophagoproteasomes. The present data, which apply to METH toxicity, are also relevant to provide a novel insight into cell clearing pathways to counteract several kinds of oxidative damage.

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Length of frenulum and interincisal distance allow an assessment of severity of ankyloglossia in children. Ankyloglossia was not associated with infantile swallowing.

In systemic autoimmune diseases, autoantibodies specific for α‐enolase are detected more frequently in patients with active renal involvement. To analyze the properties of anti‐α‐enolase antibodies and the distribution of the enzyme in the cell, mouse monoclonal and polyclonal antibodies were obtained from mice immunized with a glutathione‐S‐transferase‐α‐enolase fusion protein. Anti‐α‐enolase antibodies were purified from patient sera on enolase from human kidney. Using these antibodies, the distribution of α‐enolase in the cell was analyzed in subcellular fractions and in the cell membrane by flow cytometry and immunoprecipitation. Plasminogen binding was studied by an immunoenzymatic assay. We observed that α‐enolase was present in the cytosol and membrane fractions obtained from kidney and U937 cells. By flow cytometry, mouse polyclonal anti‐enolase antibodies, one monoclonal and 7/9 human anti‐enolase antibodies bound the membrane of U937 cells. One monoclonal antibody and mouse polyclonal anti‐enolase antibodies immunoprecipitated a 48‐kDa molecule from surface‐labeled U937 cells and this molecule was recognized by rabbit anti‐enolase antibodies. Both immunization‐induced antibodies and 7/9 autoantibodies from patient sera inhibited the binding of plasminogen to α‐enolase. The results show that α‐enolase, an autoantigen in connective tissue diseases, is a cytoplasmic enzyme which is also expressed on the cell membrane, with which it is strongly associated. Anti‐α‐enolase autoantibodies isolated from patient sera recognize the membrane‐associated form of the enzyme and/or interfere with its receptor function, thus inhibiting the binding of plasminogen. Autoantibodies specific for α‐enolase could play a pathogenic role, either by a cytopathic effect or by interfering with membrane fibrinolytic activity.

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