Impaired working memory is one symptom contributing to compromised executive function in alcohol use disorder (AUD). Dysregulation of cortical dynorphin (DYN) and κ‐opioid receptors (KORs) has been implicated in alcohol dependence‐induced impairment in executive function. The present experiments test the hypothesis that dysregulated medial prefrontal cortex (mPFC) KORs contribute to impaired working memory in alcohol dependence. Alcohol dependence was induced in male Wistar rats via 4 months of intermittent ethanol vapor exposure prior to training/testing in an mPFC‐dependent working memory task (delayed nonmatching‐to‐sample task; DNMST). mPFC KOR function in alcohol‐naïve rats was compared with that of alcohol‐dependent and nondependent rats using a DYN A‐stimulated [35S]GTPγS coupling assay. A functional role for mPFC KORs in the regulation of working memory was assessed via intra‐mPFC infusions of a KOR agonist prior to assessment in the DNMST, and the contribution of mPFC KORs to compromised working memory in dependence was assessed via mPFC infusions of the KOR antagonist norbinaltorphimine (nor‐BNI). In alcohol‐dependent rats, impaired performance in the DNMST confirmed compromised working memory. Furthermore, DYN A‐stimulated mPFC KOR function was pathologically increased in alcohol‐dependent rats compared with nondependent and alcohol‐naïve rats. Additionally, mPFC KOR involvement in working memory was functionally confirmed by intra‐mPFC KOR agonist‐induced deficits in DNMST performance. Importantly, alcohol dependence‐induced impairment in the DNMST was ameliorated by intra‐mPFC KOR antagonism. Regulation of working memory by mPFC KORs and alcohol dependence‐induced dysregulation of mPFC KOR function identify a novel therapeutic target to treat AUD‐related symptoms of working memory impairment.
The present study investigated the in vitro pharmacology of the human kappa opioid receptor using multiple assays, including calcium mobilization in cells expressing chimeric G proteins, the dynamic mass redistribution (DMR) label-free assay, and a bioluminescence resonance energy transfer (BRET) assay that allows measurement of receptor interaction with G protein and β-arrestin 2. In all assays, dynorphin A, U-69,593, and [D-Pro10]dyn(1-11)-NH2 behaved as full agonists with the following rank order of potency [D-Pro10]dyn(1-11)-NH2 > dynorphin A ≥ U-69,593. [Dmt1,Tic2]dyn(1-11)-NH2 behaved as a moderate potency pure antagonist in the kappa-β-arrestin 2 interaction assay and as low efficacy partial agonist in the other assays. Norbinaltorphimine acted as a highly potent and pure antagonist in all assays except kappa-G protein interaction, where it displayed efficacy as an inverse agonist. The pharmacological actions of novel kappa ligands, namely the dynorphin A tetrameric derivative PWT2-Dyn A and the palmitoylated derivative Dyn A-palmitic, were also investigated. PWT2-Dyn A and Dyn A-palmitic mimicked dynorphin A effects in all assays showing similar maximal effects but 3–10 fold lower potency. In conclusion, in the present study, multiple in vitro assays for the kappa receptor have been set up and pharmacologically validated. In addition, PWT2-Dyn A and Dyn A-palmitic were characterized as potent full agonists; these compounds are worthy of further investigation in vivo for those conditions in which the activation of the kappa opioid receptor elicits beneficial effects e.g. pain and pruritus.
Background Dynamic arterial elastance (Ea dyn ) has been extensively considered as a functional parameter of arterial load. However, conflicting evidence has been obtained on the ability of Ea dyn to predict mean arterial pressure (MAP) changes after fluid expansion. This meta-analysis sought to assess the predictive performance of Ea dyn for the MAP response to fluid expansion in mechanically ventilated hypotensive patients. Methods We systematically searched electronic databases through November 28, 2020, to retrieve studies that evaluated the association between Ea dyn and fluid expansion-induced MAP increases in mechanically ventilated hypotensive adults. Given the diverse threshold value of Ea dyn among the studies, we only reported the area under the hierarchical summary receiver operating characteristic curve (AUHSROC) as the primary measure of diagnostic accuracy. Results Eight observational studies that included 323 patients with 361 fluid expansions met the eligibility criteria. The results showed that Ea dyn was a good predictor of MAP increases in response to fluid expansion, with an AUHSROC of 0.92 [95% confidence interval (CI) 0.89 to 0.94]. Six studies reported the cut-off value of Ea dyn , which ranged from 0.65 to 0.89. The cut-off value of Ea dyn was nearly conically symmetrical, most data were centred between 0.7 and 0.8, and the mean and median values were 0.77 and 0.75, respectively. The subgroup analyses indicated that the AUHSROC was slightly higher in the intensive care unit (ICU) patients (0.96; 95% CI 0.94 to 0.98) but lower in the surgical patients in the operating room (0.72; 95% CI 0.67 to 0.75). The results indicated that the fluid type and measurement technique might not affect the diagnostic accuracy of Ea dyn . Moreover, the AUHSROC for the sensitivity analysis of prospective studies was comparable to that in the primary analysis. Conclusions Ea dyn exhibits good performance for predicting MAP increases in response to fluid expansion in mechanically ventilated hypotensive adults, especially in the ICU setting.
Aaron J. Norris, Jordan R. Shaker, Aaron L. Cone
et al.
Maintaining stable body temperature through environmental thermal stressors requires detection of temperature changes, relay of information, and coordination of physiological and behavioral responses. Studies have implicated areas in the preoptic hypothalamic area (POA) and the parabrachial nucleus (PBN) as nodes in the thermosensory neural circuitry and indicate the opioid system within the POA is vital in regulating body temperate. In the present study we identify neurons projecting to the POA from PBN expressing the opioid peptides Dynorphin (Dyn) and Enkephalin (Enk). We determine that warm-activated PBN neuronal populations overlap with both Dyn and Enk expressing PBN populations. We demonstrate that Dyn and Enk expressing neurons are partially overlapping subsets of a glutamatergic population in the PBN. Using optogenetic approaches we selectively activate projections in the POA from PBN Dyn, Enk, and VGLUT2 expressing neurons. Our findings demonstrate that Dyn, Enk, and VGLUT2 expressing PBN neurons are critical for physiological and behavioral heat defense.
Circulating tumor cells (CTCs) need to acquire resistance to anoikis to survive after they experience fluid shear stress in the circulatory and lymphatic systems. However, the mechanism by which tumor cells resist anoikis under shear stress conditions remains unknown. Here, we found that the application of low shear stress (LSS; 2 dyn/cm2) to human breast carcinoma cells (MDA‐MB‐231) resulted in increased anoikis resistance when tumor cells were grown under anchorage‐independent conditions. Caveolin‐1 (Cav‐1), the major component of plasma membrane caveolae, was overexpressed in LSS‐treated cells and prevented tumor cells from anoikis, while depletion of Cav‐1 restored sensitivity to anoikis. LSS‐induced dissociation of Cav‐1–Fas inhibited formation of the death‐inducing signaling complex, caspase‐8 activation, and rendered tumor cells resistant to anoikis. Likewise, LSS blocked the mitochondrial pathway through promotion of integrin β1–focal adhesion kinase‐mediated multicellular aggregation and suppression of truncated BID translocation mediated crosstalk between the extrinsic and intrinsic apoptotic pathways. Our findings provide insights into the mechanisms by which LSS induces anoikis resistance in breast carcinoma cells through inhibition of Cav‐1‐dependent extrinsic and intrinsic apoptotic pathways, and serves as a potential therapeutic target for CTCs and metastatic breast cancer.
Alec Ulasevich, Samantha Jacobs, Djass Mbangdadji
et al.
The flu causes a significant number of largely vaccine-preventable hospitalizations and deaths each year. Previous studies show that efficacy beliefs about other flu prevention strategies may be barriers to flu vaccine uptake. The purpose of this study was to assess attitudes and behaviors regarding flu vaccination and other flu prevention strategies and to examine the decision to get a flu vaccine within a competitive context. Two independent surveys were administered in 2013 (general population, n = 1,158) and 2015 (millennial panel, n = 1,574) among adults in the United States, which generated propensity models to get flu vaccines. Compared to the vaccine, participants considered many strategies to be more effective at preventing seasonal flu, particularly behaviors related to maintaining a strong immune system. Propensity models demonstrate that perceived effectiveness of some alternative “healthy behaviors” in a competitive set were associated with a lower likelihood of vaccine uptake. Results suggest that adults’ engagement in alternative strategies may be at the expense of getting vaccinated. Social marketers should consider competition not just from unhealthy behaviors but from alternative healthy behaviors when designing programs and campaigns to ensure effectiveness of their messages.
Research on the parameters of full blood count and differential white blood count is included in the program of all medical laboratories of primary, secondary and tertiary health care levels. Today, all haematological tests are exclusively performed on the haematology analyzers. Automation of haematology laboratories is a result of the huge requires for haematological test performing, timely issuing of the haematological findings, and possibility of the usage of modern techniques. This work is an evaluation of laser haematology analyzer Cell-Dyn 3700 SL. It investigates the reliability of test results throughout the following parameters: precision, accuracy, sensitivity and specificity of determination methods. It also explores the influence of sample transferring and correlation with haematology analyzer MAXM Retti. Haematology parameters that have been investigated are: white blood cell (WBC), neutrophils (NEU), lymphocytes (LXM), monocytes (MONO), eosinophils (EOS), basophils (BASO), red blood cells (RBC), haemoglobin (HGB), haematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCHC) red cell distribution width (RDW), platelet (PLT), mean platelet volume (MPV), plateletocrit (PCT), and platelet distribution width (PDW). The results confirms that precision of analyzer fulfils the reproducibility of testing parameters: WBC, RBC, HGB, MCV, MCH, MCHC, and PLT. Correlation coefficient values (r) gained throughout the statistical analysis, that is linear regression results obtained throughout the comparison of two analyzers are adequate except for MCHC (r = 0.64), what is in accordance with literature data. Accuracy is tested by haematology analyzer method and microscopic differentiating method. Correlation coefficient results for granulocytes, lymphocytes and monocytes point the accuracy of methods. Sensitivity and specificity parameters fulfil the analytical criteria. It is confirmed that haematology analyzer Cell-Dyn 3700 SL is reliable for the determination of full blood count in everyday work. Analyzer and its program for differential white blood count can be used for the research and separation of normal and pathological blood counts with addition of microscopic methods confirming distribution or morphologic changes of leukocytes.