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Receptor-type protein tyrosine phosphatase D (PTPRD) is a neuronal cell-adhesion molecule/synaptic specifier that has been implicated in addiction vulnerability and stimulant reward by human genomewide association and mouse cocaine-conditioned place-preference data. However, there have been no reports of effects of reduced expression on cocaine self-administration. There have been no reports of PTPRD targeting by any small molecule. There are no data about behavioral effects of any PTPRD ligand. We now report ( i ) robust effects of heterozygous PTPRD KO on cocaine self-administration (These data substantially extend prior conditioned place-preference data and add to the rationale for PTPRD as a target for addiction therapeutics.); ( ii ) identification of 7-butoxy illudalic acid analog (7-BIA) as a small molecule that targets PTPRD and inhibits its phosphatase with some specificity; ( iii ) lack of toxicity when 7-BIA is administered to mice acutely or with repeated dosing; ( iv ) reduced cocaine-conditioned place preference when 7-BIA is administered before conditioning sessions; and ( v ) reductions in well-established cocaine self-administration when 7-BIA is administered before a session (in WT, not PTPRD heterozygous KOs). These results add to support for PTPRD as a target for medications to combat cocaine use disorders. 7-BIA provides a lead compound for addiction therapeutics., Competing Interests: The authors declare no conflict of interest.

Background: An inverse association between serum alanine aminotransferase (ALT) levels and the risk of myocardial infarction (MI) has been reported in the general population. We investigated associations between ALT levels and the risk of various cardiovascular and cerebrovascular outcomes in a large cohort study of HIV-positive individuals., Methods: Using Poisson regression, we investigated associations between the latest ALT level and MI, coronary heart disease (CHD), and stroke, after adjusting for known confounders and cumulative/recent exposure to antiretroviral drugs. Analyses were also performed for the end points of all-cause/liver-related mortality and new-onset diabetes mellitus., Results: By February 2011, participants had experienced 541 MIs, 804 CHD, and 258 stroke events. The MI rate decreased from 3.1/1000 person-years among those with ALT ≤18 U/L to 2.1/1000 person-years among those with ALT >60 U/L. After adjustment for confounders, each 2-fold increment in ALT was associated with a 19% drop in the MI rate {relative rate, 0.81 [95% confidence interval (CI): 0.74 to 0.89], P = 0.0001}. A weaker inverse association was seen for CHD with no indication of a linear association between ALT levels and stroke (P = 0.72). Adjusted relative rates were 0.88 (95% CI: 0.81 to 0.97) and 0.70 (95% CI: 0.54 to 0.92) in those who were hepatitis C virus negative and hepatitis C virus positive, respectively, and 0.72 (95% CI: 0.58 to 0.89) and 0.84 (0.77 to 0.93) in injection drug users and non-injection drug users, respectively. Liver-related mortality and diabetes both demonstrated a positive association with ALT levels, whereas all-cause mortality showed a U-shaped relationship., Conclusions: Higher ALT levels are associated with lower MI risk in HIV-positive individuals, but with higher risks of liver-related mortality and diabetes mellitus.

Background: Liver enzymes fluctuate in chronic hepatitis C virus infection. However, the range that can be attributed to the course of hepatitis C virus (versus an intercurrent cause of hepatitis) is unknown., Aims: To characterise the range of liver enzyme values as a function of the upper limit of normal (ULN) of the assay among persons chronically infected with hepatitis C virus., Patients: One thousand and fifty-nine hepatitis C virus chronically infected individuals with > or =5 semi-annual evaluations., Methods: Alanine aminotransferase and aspartate aminotransferase levels were prospectively obtained. Potential causes of elevations were examined using serologic testing., Results: Among 1059 individuals, 11,463 enzyme measurements were obtained over 6.5 years, of which 63.5% were <1.25x ULN, 26.5% were 1.25-2.5x ULN, 8.3% were 2.5-5x ULN, and 1.6% were 5-10x ULN; only 0.2% were >10x ULN. Elevations >10x ULN were transient, the alanine aminotransferase/aspartate aminotransferase ratio tended to be different at the time of the elevation compared to before and after and 24% were associated with acute viral hepatitis. On the other hand, subjects with elevations 5-10x ULN tended to have elevated levels throughout follow-up and only 8% were associated with acute viral hepatitis., Conclusions: Liver enzymes fluctuate up to 5x ULN in most hepatitis C virus-infected persons; clinicians should seek alternate explanations for those with higher alanine aminotransferase or aspartate aminotransferase levels, especially among hepatitis C virus-infected persons with greater than 10-fold elevations.

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are the major agents responsible for hepatitis in Taiwan. The purpose of this study was to assess the serum alanine aminotransferase (ALT) activity in relation to HBV and HCV infection among drug abusers. This survey included 769 male drug abusers aged 14-59 years, from the Kaohsiung Narcotic Abstention Institute and Kaohsiung Prision. The prevalence of HBsAg seropositivity was 21.5%, and anti-HCV seropositivity was 27.2%, respectively. Drug abusers with HBsAg or anti-HCV had higher serum AST and ALT levels than those without HBsAg and anti-HCV. The prevalence of raised ALT and AST (> or =45 IU/liter) in the HCV-positive group was more significant than in the negative group, while that of the HBsAg-positive group did not reach statistical significance. Among the HCV-positive group, ALT levels are more closely associated with HCV infection than AST levels. Our results indicated that HCV infection plays an important role in the etiology of raised ALT activity among drug abusers, while HBV infection plays a minor role. ALT screening still remains a simple and valuable method in the early recognition of HCV infection.

Gingival crevicular fluid (GCF) levels of the polymorphonuclear leukocyte (PMN) lysosomal enzyme beta-glucuronidase (beta G), the pro-inflammatory cytokine interleukin 1 beta (IL-1 beta), and immunoglobulins (IgA, IgG, and IgM) were examined in 16 HIV seropositive (HIV+) and 10 HIV seronegative (HIV-) injecting drug users (IDU). Each subject received a periodontal examination including assessment of probing depth, attachment level, bleeding on probing, and plaque and calculus accumulation. GCF was collected from the mesial surfaces of premolar and molar teeth using filter paper strips. Although HIV+ subjects had a significantly lower number of peripheral blood CD4+ T cells/mm3 compared to HIV- subjects, there were no significant differences in mean probing depth, percentage of sites exhibiting bleeding on probing, or plaque and calculus accumulation between HIV- and HIV+ subjects. When the GCF components were analyzed, we found no significant differences between HIV- and HIV+ subjects in GCF levels of beta G, IL-1 beta, IgA or IgM, but GCF levels of IgG were significantly increased in HIV+ subjects. When sites were categorized by probing depth, no differences in the levels of beta G, IgA, IgG, and IgM existed between sites with probing depth < or = 3 mm compared to sites with probing depth > or = 4 mm in both HIV- and HIV+ IDU. However, levels of IL-1 beta in GCF were increased in the deeper sites (> or = 4 mm) in HIV+ IDU when compared to sites with PD < or = 3 mm. Analyzing GCF constituents in relation to the CD4 cell number, no differences were found between subjects with < or = 400 or > 400 CD4 cells/mm3 with respect to the levels of IL-1 beta, IgG, and IgM. However, the level beta G was significantly decreased in the HIV+ IDU with < or = 400 CD4 cells when compared to those with > 400 CD4 cells/mm3, while levels of IgA were significantly higher in HIV+ subjects with < or = 400 CD4 cells/mm3. Our results suggest that levels of IgG, and in immunodeficient subjects IgA were increased in GCF of HIV+ IDU while decreased levels of beta G were found in immunodeficient HIV+ IDU. These findings may be local manifestations of systemic alterations and suggest that analysis of GCF may provide insight into the immune and inflammatory responses of HIV-infected individuals to periodontal microorganisms.

The amounts of cell-surface glycosphingolipids and plasma membrane enzymes produced on the peripheral blood mononuclear cells (PBMNCs) isolated from 101 intravenous drug users (IDUs), of whom 91 were HIV-1 seropositive, were examined. Seronegative IDUs and age-matched healthy donors served as controls. The numbers of circulating CD3+, CD4+, and CD8+ T lymphocytes decreased during the advanced stages of the infection. There were also fewer CD4+ T-helper cells in HIV-1--seronegative IDU drug addicts. PBMNCs from HIV-1--seropositive subjects had abnormal surface enzyme kinetics. The phospholipase C had two pH optima, whereas the enzyme on normal cells has only one. The specific activity in cells from AIDS subjects was 4 times lower than that in normal PBMNCs. 5'-Nucleotidase showed a similar trend, whereas neutral endopeptidase activity did not correlate with the amounts of surface common acute lymphoblastic leukemia antigen (CALLA). These enzyme activities were decreased in HIV-seronegative IDUs. The subcellular distribution of enzymes and the profile of surface glycosphingolipids were also markedly changed, indicating the profound alterations in the membranes of PBMNCs from HIV-1--seropositive IDUs. These data suggest that intravenous drug use compromises the biochemical and structural integrity of the membrane surface of PBMNCs even before the onset of HIV.