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941.

Objectives

The aim was to explore the association between neighborhood deprivation and all-cause mortality and cause-specific mortalities in patients with schizophrenia and bipolar disorder. A better understanding of this potential relationship may help to identify patients with schizophrenia and bipolar disorder with an increased mortality risk.

Methods

This nationwide study included practically all adults (≥30 years) diagnosed with schizophrenia (n = 34,544) and bipolar disorder (n = 64,035) in Sweden (1997–2017). The association between neighborhood deprivation and mortality was explored using Cox regression. All models were conducted in both men and women and adjusted for individual-level sociodemographic factors and comorbidities.

Results

There was an association between level of neighborhood deprivation and all-cause mortality in both groups. The adjusted hazard ratios for all-cause mortality associated with high compared to low neighborhood deprivation were 1.18 (95% confidence interval 1.11–1.25) in patients with schizophrenia and 1.33 (1.26–1.41) in patients with bipolar disorder. The two most common mortality causes in both groups were coronary heart disease and cancer. The mortality due to coronary heart disease increased when neighborhood deprivation increased and reached 1.37 (1.18–1.60) in patients with schizophrenia and 1.70 (1.44–2.01) in patients with bipolar disorder living in the most deprived neighborhoods.

Conclusions

This study shows that neighborhood deprivation is an important risk factor for all-cause mortality and most cause-specific mortalities among patients with schizophrenia and bipolar disorder. These findings could serve as aid to policymakers when allocating healthcare resources and to clinicians who encounter patients with these conditions in deprived neighborhoods.  相似文献   
942.
Although Hodgkin''s lymphoma (HL) was one of the first human cancers to be cured by chemotherapy, no new agents other than brentuximab vedotin (Adcetris®, CD 30 directed antibody drug conjugate) have received US Food and Drug Administration (FDA) approval for HL since 1977. Subsets of young adult patients with HL continue to relapse, even after stem cell transplantation, warranting new approaches. Against this background, we report a dramatic response in a young patient with advanced HL refractory to the standard treatment who responded to the combination of a pan-histone deacetylase inhibitor (vorinostat, suberoylanilide hydroxamic acid, SAHA) and mammalian target of rapamycin (mTOR) inhibitor therapy (sirolimus,rapamume). In-depth immunohistochemical and morphoproteomic analyses of this exceptional responder to targeted therapy have yielded potential insights into the biology of advanced HL. The PI3K/AKT/mTOR pathway is a commonly activated pathway in multiple tumor types including HL. The patient was treated using therapy based on mechanistic in vitro data demonstrating that combined histone deacetylase (HDAC) and mTOR inhibition act together on this pathway, resulting in inhibition of reciprocal feedback networks, leading to better anti-proliferative activity. The in vivo response signature from this patient''s tissue sample sheds light on immune dysregulation in HL. We describe the response signature achieved from targeting immune dysregulation in addition to targeting the key oncogenic PI3K/AKT/mTOR pathway. We also expand on the role of rapamycin analogs in oncology. This study supports a role for an immune-type pathogenesis that is amenable to immune modulating targeted therapy in refractory HL.Significance: We report an exceptional responder to molecularly targeted and immune modulator therapy in advanced Hodgkin''s lymphoma. The morphoproteomic/morphometric findings in this “unusual responder” patient''s relapsed HL that correlate best, as a response signature with the subsequent clinical remission following rapamycin (sirolimus) and vorinostat (SAHA) therapies, center on an immune dysregulation involving an imbalance between effector and functional T regulatory cells in addition to targeting the mTOR pathway. This underscores the need for an approach illustrated in our study – namely of focusing on pathogenetic mechanisms and combinatorial therapies that target both the pathogenesis and adaptive responses to contemplated therapies.  相似文献   
943.
944.
945.
The growing body of evidence implicates the significance of oxidative stress in the pathophysiology of depression. The aim of this paper was to examine N-acetylcysteine (NAC) – a putative precursor of the most important tissue antioxidant glutathione – in an animal model of depression and in ex vivo assays to detect oxidative stress parameters. Imipramine (IMI), a classical and clinically-approved antidepressant drug was also under investigation. Male Wistar rats which underwent either bulbectomy (BULB; removal of the olfactory bulbs) or sham surgery (SHAM; olfactory bulbs were left undestroyed) were treated acutely or repeatedly with NAC (50–100 mg/kg, ip) or IMI (10 mg/kg, ip). Following 10-daily injections with NAC or IMI or their solvents, or 9-daily injections with a corresponding solvent plus acute NAC or acute IMI forced swimming test on day 10, and locomotor activity were performed; immediately after behavioral tests animals were decapitated. Biochemical tests (the total antioxidant capacity — TAC and the superoxide dismutase activity — SOD) were performed on homogenates in several brain structures. In behavioral studies, chronic (but not acute) administration of NAC resulted in a dose-dependent reduction in the immobility time seen only in BULB rats while chronic IMI produced a significant decrease in this parameter in both SHAM and BULB animals. On the other hand, chronic administration of NAC and IMI resulted in a significant increase in cellular antioxidant mechanisms (SOD activity) that reversed the effects of BULB in the frontal cortex, hippocampus and striatum. Our study further supports the antidepressant-like activity of NAC and links its effect as well as IMI actions with the enhancement of brain SOD activity.  相似文献   
946.
Systemic inflammatory response syndrome (SIRS) is a highly mortal inflammatory disease, associated with systemic inflammation and organ dysfunction. SIRS can have a sterile cause or can be initiated by an infection, called sepsis. The prevalence is high, and available treatments are ineffective and mainly supportive. Consequently, there is an urgent need for new treatments. The brain is one of the first organs affected during SIRS, and sepsis and the consequent neurological complications, such as encephalopathy, are correlated with decreased survival. The choroid plexus (CP) that forms the blood-CSF barrier (BCSFB) is thought to act as a brain "immune sensor" involved in the communication between the peripheral immune system and the CNS. Nevertheless, the involvement of BCSFB integrity in systemic inflammatory diseases is seldom investigated. We report that matrix metalloprotease-8 (MMP8) depletion or inhibition protects mice from death and hypothermia in sepsis and renal ischemia/reperfusion. This effect could be attributed to MMP8-dependent leakage of the BCSFB, caused by collagen cleavage in the extracellular matrix of CP cells, which leads to a dramatic change in cellular morphology. Disruption of the BCSFB results in increased CSF cytokine levels, brain inflammation, and downregulation of the brain glucocorticoid receptor. This receptor is necessary for dampening the inflammatory response. Consequently, MMP8(+/+) mice, in contrast to MMP8(-/-) mice, show no anti-inflammatory response and this results in high mortality. In conclusion, we identify MMP8 as an essential mediator in SIRS and, hence, a potential drug target. We also propose that the mechanism of action of MMP8 involves disruption of the BCSFB integrity.  相似文献   
947.
Gamma-secretase, a membrane bound protease which cleaves the transmembrane protein amyloid-β protein precursor (AβPP), is a therapeutic target for Alzheimer's disease. Gamma-secretase inhibitors (GSIs) and modulators (GSMs) are being investigated as potential disease-modifying agents. Preclinical in vivo models to monitor the activity on gamma-secretase are described in different species such as mouse, rat, and guinea pigs. All these models have their value in testing compounds with amyloid lowering properties, however, compound characteristics and pharmacokinetic properties, as well as other species characteristics such as limited sampling volumes of cerebrospinal fluid (CSF), recommended the use of a larger, non-rodent animal species. For this purpose, a screening model in dogs was developed for testing GSIs and GSMs. We showed that GSIs and GSMs had a dose- and time-dependent effect on Aβ(37), Aβ(38), Aβ(40), and Aβ(42) in CSF. Changes in liver function were evidenced by a transient increase in bilirubin with the GSMs and incidental increases in alanine aminotransferase for GSMs as well as GSIs. Microarray analysis of liver biopsies enabled to elucidate potential mechanisms behind the liver function changes. The relevance of the liver findings should be further evaluated in chronic pre-clinical safety studies and in humans. Based on our data, we can conclude that the dog is a very appropriate species to assess efficacy and safety of compounds which have an effect on AβPP processing such as GSMs, GSIs, and BACE-inhibitors.  相似文献   
948.
949.
BackgroundWe employed a cocaine intravenous self-administration model based on positive reinforcement of animals' instrumental reactions (i.e., lever pressing) rewarded by a dose of the drug. We also carried out simultaneous characterization of the phar-macokinetics of cocaine and its metabolites in rats during withdrawal; in this part of the experiments, we investigated the cocaine (2 mg/kg, iv)-induced changes in the distribution, rate constant, clearance and t1/2 of the parent drug and its metabolites in different structures of the brain and in peripheral tissues.MethodsBy using liquid chromatography-tandem mass spectrometry (LC/MS/MS) we measured the levels of cocaine and its major metabolites.ResultsOur results demonstrate differences in the levels of cocaine after cocaine self-administration in the rat, with the highest concentration seen in the striatum and the lowest in the cerebellum. Cocaine metabolites determined in the rat brain remained at very low levels (benzoylecgonine), irrespectively of the brain area, whereas the norcocaine concentration varied from 1.56 μg/g (the nucleus accumbens) to 2.73 μg/g (the striatum).ConclusionAtandem LC/MS/MS is a valid method for evaluation of brain and peripheral levels ofcocaine and its metabolites. Our results demonstrate brain area-dependent differences in the levels of cocaine after its self-administration in the rat. There were also differences in pharmacokinetic parameters among the brain areas and peripheral tissues following a bolus iv injection of cocaine to rats withdrawn from cocaine; among brain structures the slowest metabolic rate was detected for the striatum.  相似文献   
950.
The concept of intramembrane receptor-receptor interactions and evidence for their existences were introduced in the beginning of the 1980's, suggesting the existence of receptor heterodimerization. The discovery of GPCR heteromers and the receptor mosaic (higher order oligomers, more than two) has been related to the parallel development and application of a variety of resonance energy transfer techniques such as bioluminescence (BRET), fluorescence (FRET) and sequential energy transfer (SRET). The assembly of interacting GPCRs, heterodimers and receptor mosaic leads to changes in the agonist recognition, signaling, and trafficking of participating receptors via allosteric mechanisms, sometimes involving the appearance of cooperativity. The receptor interface in the GPCR heteromers is beginning to be characterized and the key role of electrostatic epitope-epitope interactions for the formation of the receptor heteromers will be discussed. Furthermore, a "guide-and-clasp" manner of receptor-receptor interactions has been proposed where the "adhesive guides" may be the triplet homologies. These interactions probably represent a general molecular mechanism for receptor-receptor interactions. It is proposed that changes in GPCR function (moonlighting) may develop through the intracellular loops and C-terminii of the GPCR heteromers as a result of dynamic allosteric interactions between different types of G proteins and other receptor interacting proteins in these domains of the receptors. The evidence for the existence of receptor heteromers opens up a new field for a better understanding of neurophysiology and neuropathology. Furthermore, novel therapeutic approaches could be possible based on the use of heteromers as targets for drug development based on their unique pharmacology.  相似文献   
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