BACKGROUND & AIMS:Some patients with SARS-CoV-2 infection have abnormal liver function. We aimed to clarify the features of COVID-19-related liver damage to provide references for clinical treatment. METHODS:We performed a retrospective, single-center study of 148 consecutive patients with confirmed COVID-19 (73 female, 75 male; mean age, 50 years) at the Shanghai Public Health Clinical Center from January 20 through January 31, 2020. Patient outcomes were followed until February 19, 2020. Patients were analyzed for clinical features, laboratory parameters (including liver function tests), medications, and length of hospital stay. Abnormal liver function was defined as increased levels of alanine and aspartate aminotransferase, gamma glutamyltransferase, alkaline phosphatase, and total bilirubin. RESULTS:Fifty-five patients (37.2%) had abnormal liver function at hospital admission; 14.5% of these patients had high fever (14.5%), compared with 4.3% of patients with normal liver function (P [ .027). Patients with abnormal liver function were more likely to be male, and had higher levels of procalcitonin and C-reactive protein. There was no statistical difference between groups in medications taken before hospitalization; a significantly higher proportion of patients with abnormal liver function (57.8%) had received lopinavir/ritonavir after admission compared to patients with normal liver function (31.3%). Patients with abnormal liver function had longer mean hospital stays (15.09 -4.79 days) than patients with normal liver function (12.76 -4.14 days) (P [ .021). CONCLUSIONS:More than one third of patients admitted to the hospital with SARS-CoV-2 infection have abnormal liver function, and this is associated with longer hospital stay. A significantly higher proportion of patients with abnormal liver function had received lopinavir/ritonavir after admission; these drugs should be given with caution.

Acute exposure to cocaine transiently induces several Fos family transcription factors in the nucleus accumbens, a region of the brain that is important for addiction. In contrast, chronic exposure to cocaine does not induce these proteins, but instead causes the persistent expression of highly stable isoforms of deltaFosB. deltaFosB is also induced in the nucleus accumbens by repeated exposure to other drugs of abuse, including amphetamine, morphine, nicotine and phencyclidine. The sustained accumulation of deltaFosB in the nucleus accumbens indicates that this transcription factor may mediate some of the persistent neural and behavioural plasticity that accompanies chronic drug exposure. Using transgenic mice in which deltaFosB can be induced in adults in the subset of nucleus accumbens neurons in which cocaine induces the protein, we show that deltaFosB expression increases the responsiveness of an animal to the rewarding and locomotor-activating effects of cocaine. These effects of deltaFosB appear to be mediated partly by induction of the AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazole) glutamate receptor subunit GluR2 in the nucleus accumbens. These results support a model in which deltaFosB, by altering gene expression, enhances sensitivity to cocaine and may thereby contribute to cocaine addiction.

Dopamine (DA) neurotransmission has been implicated in several neurological and psychiatric disorders. The dopamine transporter (DAT) is highly expressed in dopaminergic neurons of the ventral mesencephalon and regulates neurotransmission by transporting DA back into the presynaptic terminals. To mediate restricted DNA recombination events into DA neurons using the Cre/loxP technology, we have generated a knockin mouse expressing Cre recombinase under the transcriptional control of the endogenous DAT promoter. To minimize interference with DAT function by preservation of both DAT alleles, Cre recombinase expression was driven from the 3' untranslated region (3'UTR) of the endogenous DAT gene by means of an internal ribosomal entry sequence. Crossing this murine line with a LacZ reporter showed colocalization of DAT immunocytochemistry and beta-galactosidase staining in all regions analyzed. This knockin mouse can be used for generating tissue specific knockouts in mice carrying genes flanked by loxP sites, and will facilitate the analysis of gene function in dopaminergic neurons.