Constitutive μ-opioid receptor activity leads to long-term endogenous analgesia and dependence

Opioid receptor antagonists increase hyperalgesia in humans and animals, which indicates that endogenous activation of opioid receptors provides relief from acute pain; however, the mechanisms of long-term opioid inhibition of pathological pain have remained elusive. We found that tissue injury produced μ-opioid receptor (MOR) constitutive activity (MOR(CA)) that repressed spinal nociceptive signaling for months. Pharmacological blockade during the posthyperalgesia state with MOR inverse agonists reinstated central pain sensitization and precipitated hallmarks of opioid withdrawal (including adenosine 3',5'-monophosphate overshoot and hyperalgesia) that required N-methyl-D-aspartate receptor activation of adenylyl cyclase type 1. Thus, MOR(CA) initiates both analgesic signaling and a compensatory opponent process that generates endogenous opioid dependence. Tonic MOR(CA) suppression of withdrawal hyperalgesia may prevent the transition from acute to chronic pain.

Genetic polymorphisms of LPL and HL and their association with the performance of Chinese sturgeons fed a formulated diet

It is very important to investigate the reasons for the large individual differences in individual performance of food acceptance when using formulated diets for the successful culture of larvae and juveniles of the Chinese sturgeon Acipenser sinensis. Genetic differences of the mitochondrial control region were investigated by direct sequencing in two groups of Chinese sturgeon, which were apt to accept or refuse formulated diets. Among 968-bp sequences, 111 variable sites were identified. One variable site showed close association with the individual performance of specimens fed with formulated diets. The commercial diet for Chinese sturgeons usually contains high levels of lipids. Lipoprotein lipase (LPL) and hepatic lipase (HL) are two members of the lipase gene family, which are essential for the utilization of dietary lipid. Single nucleotide polymorphisms (SNPs) in intron 7 were detected in the two experimental groups of Chinese sturgeons. We were able to demonstrate that one SNP in the LPL gene and one SNP in the HL gene showed close association with the performance of sturgeons on the formulated diet.

Dietary patterns as compared with physical activity in relation to metabolic syndrome among Chinese adults

AIMS

To examine the nationally-representative dietary patterns and their joint effects with physical activity on the likelihood of metabolic syndrome (MS) among 20,827 Chinese adults.

METHODS AND RESULTS

CNNHS was a nationally representative cross-sectional observational study. Metabolic syndrome was defined according to the Joint Interim Statement definition. The "Green Water" dietary pattern, characterized by high intakes of rice and vegetables and moderate intakes in animal foods was related to the lowest prevalence of MS (15.9%). Compared to the "Green Water" dietary pattern, the "Yellow Earth" dietary pattern, characterized by high intakes of refined cereal products, tubers, cooking salt and salted vegetable was associated with a significantly elevated odds of MS (odds ratio 1.66, 95%CI: 1.40-1.96), after adjustment of age, sex, socioeconomic status and lifestyle factors. The "Western/new affluence" dietary pattern characterized by higher consumption of beef/lamb, fruit, eggs, poultry and seafood also significantly associated with MS (odds ratio: 1.37, 95%CI: 1.13-1.67). Physical activity showed significant interactions with the dietary patterns in relation to MS risk (P for interaction = 0.008). In the joint analysis, participants with the combination of sedentary activity with the "Yellow Earth" dietary pattern or the "Western/new affluence" dietary pattern both had more than three times (95%CI: 2.8-6.1) higher odds of MS than those with active activity and the "Green Water" dietary pattern.

CONCLUSIONS

Our findings from the large Chinese national representative data indicate that dietary patterns affect the likelihood of MS. Combining healthy dietary pattern with active lifestyle may benefit more in prevention of MS.

Antimicrobial penetration in a dual-species oral biofilm after noncontact brushing: an in vitro study

OBJECTIVES

Oral biofilm is inevitably left behind, even after powered brushing. As a special feature, powered brushing removes biofilm in a noncontact mode. When the brushing distance becomes too large, biofilm is left behind. We hypothesize that biofilm left behind after brushing has different viscoelastic properties than before brushing, impacting antimicrobial penetration.

MATERIALS AND METHODS

In vitro grown dual-species biofilms were subjected to 20 % mechanical deformation before and after powered brushing at 4-mm brushing distance. Biofilm thickness and stress relaxation were measured for unbrushed and brushed biofilms. Stress relaxation was analyzed with a three-element Maxwell model. Antimicrobial penetration from five mouthrinses was microscopically evaluated for unbrushed and brushed biofilms.

RESULTS

Thicknesses of unbrushed and brushed biofilms were similar. Brushing decreased the prevalence of fast and increased the prevalence of slow relaxation elements, which was accompanied by deeper penetration of chlorhexidine and cetylpyridinium chloride. Penetration of antimicrobials from other mouthrinses was relatively low in unbrushed and brushed biofilms.

CONCLUSIONS

This confirmation of our hypothesis points to an additional advantage of powered toothbrushing in a noncontact mode, changing the viscoelastic properties of biofilm in a direction that increases antimicrobial penetration of chlorhexidine and cetylpyridinium.

CLINICAL RELEVANCE

The biofilm left behind after noncontact powered toothbrushing may have less recalcitrance toward penetration of chlorhexidine and cetylpyridinium chloride than prior to brushing.

Induced maturation of hepatic progenitor cells in vitro

Hepatic progenitor cells (HPCs) are a potential cell source for liver cell transplantation but do not function like mature liver cells. We sought an effective and reliable method to induce HPC maturation. An immortalized HP14.5 albumin promoter-driven Gaussian luciferase (ALB-GLuc) cell line was established from HPCs isolated from fetal mouse liver of post coitus day 14.5 mice to investigate the effect of induction factors on ALB promoter. HP14.5 parental cells were cultured in DMEM with different combinations of 2% horse serum (HS), 0.1 µM dexamethasone (DEX), 10 ng/mL hepatic growth factor (HGF), and/or 20 ng/mL fibroblast growth factor 4 (FGF4). Trypan blue and crystal violet staining were used to assess cell proliferation with different induction conditions. Expression of hepatic markers was measured by semi-quantitative RT-PCR, Western blot, and immunofluorescence. Glycogen storage and metabolism were detected by periodic acid-Schiff and indocyanine green (ICG) staining. GLuc activity indicated ALB expression. The combination of 2% HS+0.1 µM Dex+10 ng/mL HGF+20 ng/mL FGF4 induced the highest ALB-GLuc activity. Cell proliferation decreased in 2% HS but increased by adding FGF4. Upon induction, and consistent with hepatocyte development, DLK, AFP, and CK19 expression decreased, while ALB, CK18, and UGT1A expression increased. The maturity markers tyrosine aminotransferase and apolipoprotein B were detected at days 3 and 6 post-induction, respectively. ICG uptake and glycogen synthesis were detectable at day 6 and increased over time. Therefore, we demonstrated that HPCs were induced to differentiate into functional mature hepatocytes in vitro, suggesting that factor-treated HPCs may be further explored as a means of liver cell transplantation.

Image Segmentation for Image-Based Dietary Assessment: A Comparative Study

There is a health crisis in the US related to diet that is further exacerbated by our aging population and sedentary lifestyles. Six of the ten leading causes of death in the United States can be directly linked to diet. Dietary assessment, the process of determining what someone eats during the course of a day, is essential for understanding the link between diet and health. We are developing imaging based tools to automatically obtain accurate estimates of what foods a user consumes. Accurate food segmentation is essential for identifying food items and estimating food portion sizes. In this paper, we present a quantitative evaluation of automatic image segmentation methods for food image analysis used for dietary assessment. The experiments indicate that local variation is more suitable for food image segmentation in general dietary assessment studies where the food images acquired have complex background.

Gαq gene promoter polymorphisms and rheumatoid arthritis in the Han Chinese population are not associated

Mice that lose Gαq from their immune system can spontaneously develop inflammatory arthritis. Gαq expression in the peripheral blood lymphocytes of rheumatoid arthritis (RA) patients is significantly decreased in comparison to that in healthy individuals, and reduced Gαq expression is closely correlated with RA disease activity. These indicate that Gαq plays critical roles in the pathogenesis of RA. To address whether single nucleotide polymorphism in the promoter region of the Gαq gene (GNAQ) influenced Gαq expression in RA patients and was a genetic risk factor for RA, we sequenced the promoter region of GNAQ in a Han Chinese population. A common dinucleotide polymorphism at position -695/-694, an exchange of 2 adjacent nucleotides (GC>TT), was revealed in 118 RA patients and 101 healthy adults. The proportions of genotypes observed for -695/-694 in the RA group were GC/GC (65.25%), GC/TT (33.05%), and TT/TT (1.70%), and those in the control group were GC/GC (62.38%), GC/TT (33.66%), and TT/TT (3.96%). No significant difference in the allele and genotype frequencies between RA patients and healthy controls for dinucleotide polymorphism was found in the Han Chinese population, neither in the whole data set nor in stratified subsets, i.e., rheumatoid factors, anti-cyclic citrullinated peptide antibody, and Gαq expression status (P > 0.05). We conclude that the GNAQ promoter polymorphism is not a genetic risk factor for RA in the Han Chinese population, and that decreased Gαq expression in peripheral blood lymphocytes of RA might potentially be due to other causes.

Transplantation KCNMA1 modified bone marrow-mesenchymal stem cell therapy for diabetes mellitus-induced erectile dysfunction

This study assessed the effect of KCNMA1 transfected bone marrow-mesenchymal stem cells (BM-MSCs) on the improvement of erectile function in diabetic rats. Sixty male Sprague-Dawley rats were injected with streptozotocin (STZ) and screened with apomorphine (APO) to establish diabetes mellitus-induced erectile dysfunction (DMED). DMED rats were randomly divided into four groups: rats in each group underwent intracavernous injection with either phosphate buffer solution (DMED+PBS), nontransfected MSCs (DMED+MSCs), empty vector transfected MSCs (DMED+null-MSCs) or KCNMA1 transfected MSCs (DMED+KCNMA1-MSCs). Before injection, high levels of KCNMA1 expression were confirmed in KCNMA1-MSCs using RT-PCR and Western blotting. The lentivirus transfected MSCs maintained their potential for multidirectional differentiation. Four weeks after injection, erectile function was ascertained by measuring intracavernous pressure (ICP). Penile tissues were collected for immunohistochemical analysis. The expression of KCNMA1 in the corpus cavernosum was increased, and the DMED+KCNMA1-MSCs group displayed a significant improvement of erectile function. We concluded that KCNMA1 was able to enhance the positive effect of MSCs in the treatment of diabetes-associated erectile dysfunction.

Efficacy and safety of lorcaserin in obese adults: a meta-analysis of 1-year randomized controlled trials (RCTs) and narrative review on short-term RCTs

Lorcaserin is a new anti-obesity drug recently approved by US Food and Drug Administration. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the association of lorcaserin therapy with weight loss and adverse events in obese adults (18-65 years old). Weight loss of 3.23 kg (95% confidence interval [CI]: 2.70, 3.75) and body mass index reduction of 1.16 kg m⁻² (95% CI: 0.98, 1.34) was observed compared with placebo in RCTs of 1 year duration. The use of lorcaserin for 8 and 12 weeks reduced weight of 1.60 kg (95% CI: 0.34, 2.86) and 2.9 kg (95% CI: 2.2, 3.5), respectively. In comparison to placebo, lorcaserin decreased waist circumference, blood pressure, total cholesterol, low-density lipoprotein-cholesterol and triglycerides, however did not statistically affect heart rate or high-density lipoprotein-cholesterol. Headache, nausea and dizziness were found to be significantly higher in the patients receiving lorcaserin than patients receiving placebo, whereas diarrhoea is no more likely than in patients receiving placebo. In conclusion, lorcaserin achieves modest weight loss and appears to be well tolerated. Clinical and pharmacovigilance studies with longer study duration are needed to inform of the long-term efficacy and safety of lorcaserin.