Detection of nitrite with a surface-enhanced Raman scattering sensor based on silver nanopyramid array.

Nutrient pollution is of worldwide environmental and health concerns due to extensive use of nitrogen fertilizers and release of livestock waste, which induces nitrite compounds in aquatic systems. Herein a surface-enhanced Raman scattering (SERS) sensor is developed for nitrite detection based on coupling between the plasmonic gold nanostars and the silver nanopyramid array. When nitrite is present in the assay, an azo group is formed between the 1-naphthylamine-functionalized silver nanopyramids and the 4-aminothiophenol-functionalized gold nanostars. This not only generates the SERS spectral fingerprint for selective detection, but also creates "hot spots" at the gap between the Au nanostars and the Ag nanopyramids where the azo group is located, amplifying SERS signals remarkably. Finite-difference time-domain (FDTD) simulation shows a SERS enhancement factor of 4 × 1010 at the "hot spots". As a result, the SERS sensor achieves a limit of detection of 0.6 pg/mL toward nitrite in water, and enables nitrite detection in real-world river water samples. In addition, this sensor eliminates the use of any Raman reporter and any expensive molecular recognition probe such as antibody and aptamer. This highly sensitive, selective and inexpensive SERS sensor has unique advantages over colorimetric, electrochemical and fluorescent devices for small molecule detection.

Measurement-based Care in Psychiatry-Past, Present, and Future.

The authors define measurement-based care (MBC) in psychiatry as the use of validated clinical measurement instruments to objectify the assessment, treatment, and clinical outcomes, including efficacy, safety, tolerability, functioning, and quality of life, in patients with psychiatric disorders. MBC includes two processes: routine assessments, such as measuring the severity of symptoms with rating scales, and the use of assessments in decision-making. MBC implementation was tested in the Texas Medication Algorithm Project and the German Algorithm Project and has been shown to improve patient outcomes. Even though more recent research has shown the many benefits of MBC compared to the usual care, MBC is still not the standard of care in psychiatric practice. This review article addresses the advantages of MBC, the barriers to implementing MBC in clinical practice, and the basic properties of MBC instruments. Recent developments in the 21st century that are expected to accelerate the adoption of MBC in clinical practice, including electronic health records, health information technology, and the development of the Standard for Clinicians' lnterview in Psychiatry (SCIP) as an MBC tool, will be reviewed. The authors recommend including MBC in psychiatry residency training to promote its use in future generations.

The glutamate hypothesis of schizophrenia: evidence from human brain tissue studies.

A number of studies have indicated that antagonists of the N-methyl-d-aspartate subtypes of glutamate receptors can cause schizophrenia-like symptoms in healthy individuals and exacerbate symptoms in individuals with schizophrenia. These findings have led to the glutamate hypothesis of schizophrenia. Here we review the evidence for this hypothesis in postmortem studies of brain tissue from individuals affected by schizophrenia, summarizing studies of glutamate neuron morphology, of expression of glutamate receptors and transporters, and of the synthesizing and metabolizing enzymes for glutamate and its co-agonists. We found consistent evidence of morphological alterations of dendrites of glutamatergic neurons in the cerebral cortex of subjects with schizophrenia and of reduced levels of the axon bouton marker synaptophysin. There were no consistent alterations of mRNA expression of glutamate receptors, although there has been limited study of the corresponding proteins. Studies of the glutamate metabolic pathway have been limited, although there is some evidence that excitatory amino acid transporter-2, glutamine synthetase, and glutaminase have altered expression in schizophrenia. Future studies would benefit from additional direct examination of glutamatergic proteins. Further advances, such as selective testing of synaptic microdomains, cortical layers, and neuronal subtypes, may also be required to elucidate the nature of glutamate signaling impairments in schizophrenia.