Selective and absolute quantification of endogenous hypochlorous acid with quantum-dot conjugated microbeads.

Endogenous hypochlorous acid (HOCl) secreted by leukocytes plays a critical role in both the immune defense of mammalians and the pathogenesis of various diseases intimately related to inflammation. We report the first selective and absolute quantification of endogenous HOCl produced by leukocytes in vitro and in vivo with a novel quantum dot-based sensor. An activated human neutrophil secreted 6.5 ± 0.9 × 10(8) HOCl molecules into its phagosome, and kinetic measurement for the secretions showed that the extracellular generation of HOCl was temporally retarded, but the quantity eventually attained a level comparable with its intraphagosomal counterpart with a delay of about 1.5 h. The quantity of HOCl secreted from the hepatic leukocytes of rats with or without stimulation of lipopolysaccharide was also determined. These results indicate a possibility to extend our approach to not only clinical settings for quantitative assessment of the bactericidal capability of isolated leukocytes of patients but also fundamental biomedical research that requires critical evaluation of the inflammatory response of animals.

Leptin and interleukin-1beta modulate neuronal glutamate release and protect against glucose-oxygen-serum deprivation.

Molecular mechanism underlying leptin-mediated neuronal protection against glucose-oxygen-serum deprivation (GOSD) insult was investigated by focusing on the interactions among leptin, Interleukin-1beta (IL-1beta) and glutamate and their impacts on the growth of neurons under GOSD. The trypan blue dye exclusion assay, 4', 6-diamidino-2-phenylindole (DAPI) assay, cytokine antibody array assay, immunocytochemical staining assay, glutamate determination kit, immunoblocking and chemical blocking strategies were applied to serve the study goal. Results showed that in response to 6 h of GOSD, cortical neurons can secrete significant amounts of leptin and IL-1beta to protect neurons from GOSD-induced cell damage. Serine/threonine kinase Akt (Akt) and extracellular signal-related kinase (ERK) inhibitors significantly reversed leptin-mediated neuroprotection. GOSD-induced IL-1beta was further enhanced by leptin in Akt/ERK-dependent manner. Blockade of endogenous leptin with specific antibodies significantly inhibited GOSD-induced IL-1beta expression and increased glutamate release from GOSD neurons. IL-1 blockade with IL-1 receptor antagonist (IL-1ra) on the other hand, inhibited leptin-mediated neuroprotection and suppression of glutamate release from GOSD neurons. Pre-treating GOSD neurons with leptin and IL-1beta in combined significantly increased their survival but decreased their releases of glutamate. The results indicate that leptin may act through Akt and ERK signaling pathways to protect neurons from GOSD insult; the protection was in part IL-1beta dependent and through which the glutamate release from GOSD neurons was inhibited. Therapeutic values of leptin and IL-1beta were suggested in the treatment of cerebral ischemia at early stage.

Molecules involve in the self-protection of neurons against glucose-oxygen-serum deprivation (GOSD)-induced cell damage.

Molecules involved in self-protection of neurons against glucose/oxygen/serum deprivation (GOSD) were investigated. Trypan blue dye exclusion assay, Western blotting, ELISA, cytokine antibody array and chemical blocking assay were applied in the study. Results showed that early induction (at 6h of GOSD) of cyclooxygenase-2 (COX-2), leptin, transforming growth factor-beta1 (TGF-beta1), glial-cell-line-derived neurotrophic factor (GDNF) and neurotrophin-3 (NT-3) all played a compensatory role in the protection of neurons against GOSD. Decline of these molecules and peroxisome proliferators-activated receptor (PPAR)-gamma and -alpha since 12h of GOSD may lead to an irreversible neuronal death. Nitric oxide (NO) and superoxide at low concentrations were neuroprotective whereas at high concentrations were detrimental to neurons. Accumulation of NO and superoxide at late stage of GOSD should therefore be prevented. The study provided a useful platform for screening of potential anti-ischemic drugs and also explained why GOSD neuron derived conditioned medium (NCM) only exerted a time-restricted neuroprotection.

Ischemic brain cell-derived conditioned medium protects astrocytes against ischemia through GDNF/ERK/NF-kB signaling pathway.

Conditioned medium (CM) collected from cultures of ischemic microglia, astrocytes, and neurons were protective to astrocytes under the in vitro ischemic condition (deprivation of oxygen, glucose and serum). Molecular and signaling pathway(s) responsible for the CMs protective activity were investigated. Results showed that CMs from the ischemic microglia (MCM), astrocytes (ACM) and neurons (NCM) contained glial cell line-derived neurotrophic factor (GDNF), which protects astrocytes against the in vitro ischemia. Expression of extra cellular signal-regulated kinase (ERK1/2) and nuclear factor-kappa B (NF-kB) by GDNF led to the inhibition of apoptosis of the ischemic astrocytes in a caspase 3-independent manner. However, CMs- and GDNF-mediated protection of the ischemic astrocytes was protein kinase B (Akt) independent. These results provided mechanistic data regarding how GDNF- and CMs-mediated protection of the ischemic astrocytes is taking place. These observations provide information for the use of GDNF and GDNF containing CMs in the control of cerebral ischemia.

Screening for autism spectrum disorder in adult psychiatric outpatients in a clinic in Taiwan.

Patients with adult autism spectrum disorder (ASD) continue to suffer from impairment in socialization and communication skills, and a proportion of them may develop psychiatric symptoms. It is thus likely that physicians in adult psychiatric departments may see a number of patients with ASD. Identification of patients with ASD is helpful and important for rehabilitation. This study estimated the prevalence of ASD among adult psychiatric outpatients in a Taiwanese medical center. A total of 660 patients were screened with Nylander and Gillberg's "Autism Spectrum Disorder in Adult Screening Questionnaire." Patients with high scores then underwent a diagnostic clinical interview conducted by child psychiatrists. Four patients (0.6%) were found to have ASD.