Glutamatergic and GABAergic metabolite levels in schizophrenia-spectrum disorders: a meta-analysis of 1H-magnetic resonance spectroscopy studies.

BACKGROUND: The glutamate (Glu) and gamma aminobutyric acid (GABA) hypotheses of schizophrenia were proposed in the 1980s. However, current findings on those metabolite levels in schizophrenia have been inconsistent, and the relationship between their abnormalities and the pathophysiology of schizophrenia remains unclear. To summarize the nature of the alterations of glutamatergic and GABAergic systems in schizophrenia, we conducted meta-analyses of proton magnetic resonance spectroscopy (1H-MRS) studies examining these metabolite levels. METHODS: A systematic literature search was conducted using Embase, Medline, PsycINFO, and PubMed. Original studies that compared four metabolite levels (Glu, glutamine [Gln], Glx [Glu+Gln], and GABA), as measured by 1H-MRS, between individuals at high risk for psychosis, patients with first-episode psychosis, or patients with schizophrenia and healthy controls (HC) were included. A random-effects model was used to calculate the effect sizes for group differences in these metabolite levels of 18 regions of interest between the whole group or schizophrenia group and HC. Subgroup analysis and meta-regression were performed based on the status of antipsychotic treatment, illness stage, treatment resistance, and magnetic field strength. RESULTS: One-hundred-thirty-four studies met the eligibility criteria, totaling 7993 participants with SZ-spectrum disorders and 8744 HC. 14 out of 18 ROIs had enough numbers of studies to examine the group difference in the metabolite levels. In the whole group, Glx levels in the basal ganglia (g = 0.32; 95% CIs: 0.18-0.45) were elevated. Subgroup analyses showed elevated Glx levels in the hippocampus (g = 0.47; 95% CIs: 0.21-0.73) and dorsolateral prefrontal cortex (g = 0.25; 95% CIs: 0.05-0.44) in unmedicated patients than HC. GABA levels in the MCC were decreased in the first-episode psychosis group compared with HC (g = -0.40; 95% CIs: -0.62 to -0.17). Treatment-resistant schizophrenia (TRS) group had elevated Glx and Glu levels in the MCC (Glx: g = 0.7; 95% CIs: 0.38-1.01; Glu: g = 0.63; 95% CIs: 0.31-0.94) while MCC Glu levels were decreased in the patient group except TRS (g = -0.17; 95% CIs: -0.33 to -0.01). CONCLUSIONS: Increased glutamatergic metabolite levels and reduced GABA levels indicate that the disruption of excitatory/inhibitory balance may be related to the pathophysiology of schizophrenia-spectrum disorders.

How to manage tension gastrothorax: a case report of tension gastrothorax with multiple trauma due to traumatic diaphragmatic rupture.

BACKGROUND: Tension gastrothorax is a kind of obstructive shock with prolapse and distention of the stomach into the thoracic cavity. Progressive gastric distension leads to mediastinal shift, reduced venous return, decreased cardiac output, and ultimately cardiac arrest. Therefore, it is crucial to decompress the stomach distension for the initial resuscitation of tension gastrothorax. CASE PRESENTATION: A 75-year-old female was transported to our resuscitation bay due to motor vehicle crash. At the time of arrival to our hospital, the patient developed cardiac arrest. While undergoing cardiopulmonary resuscitation, an unstable pelvic ring was recognized, so we performed a resuscitative thoracotomy to control hemorrhage and to perform direct cardiac massage. Once we performed the thoracotomy, the stomach and omentum prolapsed out of the thoracotomy site and through the diaphragm rupture site and spontaneous circulation was recovered. Neither the descending aorta nor the heart was collapsed. Although we had continued the treatment for severe pelvic fracture (including blood transufusions), the patient died. Given that (1) the stomach prolapsed out of the body at the time of the thoracotomy; (2) at the same timing, spontaneous circulation returned; and (3) the descending aorta and heart did not collapse, we hypothesized that the main cause of the initial cardiac arrest was tension gastrothorax. CONCLUSIONS: Recognition of tension gastrothorax pathophysiology, which is a form of obstructive shock, makes it possible to manage this injury correctly.