Trace amines: identification of a family of mammalian G protein-coupled receptors

Tyramine, beta-phenylethylamine, tryptamine, and octopamine are biogenic amines present in trace levels in mammalian nervous systems. Although some "trace amines" have clearly defined roles as neurotransmitters in invertebrates, the extent to which they function as true neurotransmitters in vertebrates has remained speculative. Using a degenerate PCR approach, we have identified 15 G protein-coupled receptors (GPCR) from human and rodent tissues. Together with the orphan receptor PNR, these receptors form a subfamily of rhodopsin GPCRs distinct from, but related to the classical biogenic amine receptors. We have demonstrated that two of these receptors bind and/or are activated by trace amines. The cloning of mammalian GPCRs for trace amines supports a role for trace amines as neurotransmitters in vertebrates. Three of the four human receptors from this family are present in the amygdala, possibly linking trace amine receptors to affective disorders. The identification of this family of receptors should rekindle the investigation of the roles of trace amines in mammalian nervous systems and may potentially lead to the development of novel therapeutics for a variety of indications.

Hepatitis C in HIV-infected patients with and without AIDS: prevalence and relationship to patient survival

BACKGROUND

Limited information is available about the prevalence of hepatitis C virus in patients with human immunodeficiency virus in relation to specific risk factors or about the influence of hepatitis C virus coinfection on survival. This retrospective study addressed these questions.

METHODS

The study population consisted of 512 predominantly non-intravenous drug-using male homosexuals, 224 of whom had AIDS. Samples positive for hepatitis C virus antibody by second-generation enzyme immunoassay were further tested by means of strip immunoblot assay, and for hepatitis C virus RNA by means of polymerase chain reaction amplification. A randomly selected set of enzyme immunoassay-negative samples was also tested for hepatitis C virus RNA and, if hepatitis C virus RNA positive, by a second-generation recombinant immunoblot assay.

RESULTS

The prevalence of hepatitis C virus infection unaccounted for by intravenous drug use or transfusion was 11.7% by enzyme immunoassay, and 87% of sera positive by enzyme immunoassay were also positive by second-generation recombinant immunoblot assay or hepatitis C virus RNA analysis. Hepatitis C virus RNA was detectable in 53% of enzyme immunoassay-positive samples but in only about 1% of enzyme immunoassay-negative samples. Hepatitis C virus coinfection did not influence survival of HIV-infected patients with or without manifestations of AIDS.

CONCLUSIONS

Hepatitis C virus infection in nontransfused, non-intravenous drug-using patients with HIV infection is several times more prevalent than in volunteer blood donors, suggesting homosexual transmission of hepatitis C virus. About half of patients seropositive for hepatitis C virus antibody have detectable hepatitis C virus RNA, and serologically occult hepatitis C virus viremia is rare. Hepatitis C virus coinfection does not appear to adversely influence survival.

Enhanced surface ozone during the heat wave of 2013 in Yangtze River Delta region, China

Under the background of global warming, occurrence of heat waves has increased in most part of Europe, Asia and Australia along with enhanced ozone level. In this paper, observational air temperature and surface ozone in the Yangtze River Delta (YRD) region of China during summer of 2013, and the regional chemistry-climate model (RegCM-CHEM4) were applied to explore the relationship between heat wave and elevated ground-level ozone. Observations indicated that YRD experienced severe heat waves with maximum temperature up to 41.1°C, 6.1°C higher than the definition of heat wave in China, and can last for as long as 27days. Maximum ozone reached 160.5ppb, exceeding the national air quality standard (secondary level) as 74.7ppb. Moreover, ozone was found to increase at a rate of 4-5ppbK^-1 within the temperature range of 28-38°C, but decrease by a rate of -1.3~-1.7ppbK^-1 under extremely high temperature. A typical heat wave case (HW: 24/7-31/7) and non-heat wave case (NHW: 5/6-12/6) were selected to investigate the mechanism between heavy ozone and heat waves. It was found that chemical reactions play the most important role in ozone formation during HW days, which result in 12ppb ozone enhancement compared to NHW days. Chemical formation of ozone can be influenced by several factors. During heat waves, a more stagnant condition, controlled by anti-cyclone with sink airflow, led to less water vapor in YRD from south and contributed to less cloud cover, which favored a strong solar radiation environment and ozone significantly increasing. High temperature also slightly promote the effect of vertical turbulence and horizontal advection, which beneficial to ozone remove, but the magnitude is much smaller than chemical effect. Our study suggests that the chemical reaction will potentially lead to substantial elevated ozone in a warmer climate, which should be taken into account in future ozone related issues.

Chronic hypoxemia selectively down-regulates 11beta-hydroxysteroid dehydrogenase type 2 gene expression in the fetal sheep kidney

The present study was designed to examine the effects of chronic fetal placental embolization on the expression of 11beta-hydroxysteroid dehydrogenase (11beta-HSD) types 1 and 2, the intracellular enzymes responsible for the metabolism of glucocorticoids. Twelve instrumented fetal sheep were randomly allocated on Day 110 (term = 147 days) to either a control (n = 6) or embolized (n = 6) group. Embolized fetuses received daily injections of nonradioactive microspheres into the abdominal aorta for 21 days to decrease arterial oxygen content by 40-50% of the pre-embolization values. At the end of the experiment, fetal liver and kidney tissues as well as placental cotyledons were collected, and tissue levels of 11beta-HSD mRNA and activity were determined by standard Northern blot analysis and radiometric conversion assay, respectively. There was a 44% reduction (p < 0.01) in the level of renal 11beta-HSD2 mRNA in the embolized group as compared with the control group. Moreover, this reduction in mRNA was carried through to 11beta-HSD2 protein, since there was a corresponding decrease in the level of 11beta-HSD2 activity (4.5+/-0.2 vs. 2.9+/-0.1 pmol/min per milligram protein, p < 0.01). In contrast, levels of both 11beta-HSD1 mRNA and activity in the fetal liver remained unchanged. Moreover, both 11beta-HSD types 1 and 2 mRNA and activity in the placenta were not altered by the fetal placental embolization. In conclusion, chronic hypoxemia selectively inhibits renal 11beta-HSD2 mRNA expression and enzyme activity in the ovine fetus, which may contribute, at least in part, to the mechanisms leading to fetal hypertension.

Inflammation-related genetic variants predict toxicity following definitive radiotherapy for lung cancer

Definitive radiotherapy improves locoregional control and survival in inoperable non-small cell lung cancer (NSCLC) patients. However, radiation-induced toxicities (pneumonitis/esophagitis) are common dose-limiting inflammatory conditions. We therefore conducted a pathway-based analysis to identify inflammation-related SNPs associated with radiation-induced pneumonitis or esophagitis. 11,930 SNPs were genotyped in 201 stage I-III NSCLC patients treated with definitive radiotherapy. Validation was performed in an additional 220 NSCLC cases. After validation, 19 SNPs remained significant. A polygenic risk score (PRS) was generated to summarize the effect from validated SNPs. Significant improvements in discriminative ability were observed by adding the PRS into the clinical/epidemiological variable-based model. We then used 277 lymphoblastoid cell-lines to assess radiation sensitivity and eQTL relationships of the identified SNPs. Three genes (PRKCE,DDX58 and TNFSF7) were associated with radiation sensitivity. We concluded that inflammation-related genetic variants could contribute to the development of radiation-induced toxicities. These loci could assist in predicting those unfavorable events.

Recovery of stem cell proliferation by low intensity vibration under simulated microgravity requires LINC complex

Mesenchymal stem cells (MSC) rely on their ability to integrate physical and spatial signals at load bearing sites to replace and renew musculoskeletal tissues. Designed to mimic unloading experienced during spaceflight, preclinical unloading and simulated microgravity models show that alteration of gravitational loading limits proliferative activity of stem cells. Emerging evidence indicates that this loss of proliferation may be linked to loss of cellular cytoskeleton and contractility. Low intensity vibration (LIV) is an exercise mimetic that promotes proliferation and differentiation of MSCs by enhancing cell structure. Here, we asked whether application of LIV could restore the reduced proliferative capacity seen in MSCs that are subjected to simulated microgravity. We found that simulated microgravity (sMG) decreased cell proliferation and simultaneously compromised cell structure. These changes included increased nuclear height, disorganized apical F-actin structure, reduced expression, and protein levels of nuclear lamina elements LaminA/C LaminB1 as well as linker of nucleoskeleton and cytoskeleton (LINC) complex elements Sun-2 and Nesprin-2. Application of LIV restored cell proliferation and nuclear proteins LaminA/C and Sun-2. An intact LINC function was required for LIV effect; disabling LINC functionality via co-depletion of Sun-1, and Sun-2 prevented rescue of cell proliferation by LIV. Our findings show that sMG alters nuclear structure and leads to decreased cell proliferation, but does not diminish LINC complex mediated mechanosensitivity, suggesting LIV as a potential candidate to combat sMG-induced proliferation loss.

Guinea pig 11beta-hydroxysteroid dehydrogenase type 1: primary structure and catalytic properties

The 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) enzyme is responsible for the interconversion of glucocorticoids and their inactive metabolites, and thus modulates the intracellular level of bioactive glucocorticoids. The present study was designed to clone and characterize 11beta-HSD1 in the guinea pig, a laboratory animal known for resistance to glucocorticoids. The cDNA encoding guinea pig 11beta-HSD1 was cloned by a modified 3'-RACE (rapid amplification of cDNA ends) protocol using the hepatic RNA as template. The cloned cDNA encodes a protein of 300 amino acids that shares 71 to 74% sequence identity with other known mammalian 11beta-HSD1 proteins. Sequence comparison analysis revealed that the deduced guinea pig 11beta-HSD1 was longer, by eight amino acids at the C terminus, than those of other mammals. Moreover, one of the two absolutely conserved consensus sites for N-glycosylation was absent. To examine the functional significance of these structural changes, we also characterized 11beta-HSD1 activity in the hepatic microsomes. Although the guinea pig hepatic enzyme was NADP(H)-dependent and reversible, it displayed equal affinity for cortisol and cortisone (apparent K(m) for both substrates was 3 microM). This is in marked contrast to 11beta-HSD1 in other mammals whose affinity for cortisone is approximately 10 times higher than that for cortisol (apparent K(m) of 0.3 vs. 3.0 microM). The apparent lower affinity of the guinea pig enzyme for cortisone would suggest that the intracellular bioformation of cortisol from circulating cortisone may be less efficient in this species. Northern blot analysis and RT-PCR revealed that the mRNA for 11beta-HSD1 was widely expressed in the adult guinea pig but at low amounts. In conclusion, the present study has identified distinct features in the deduced primary structure and catalytic function of 11beta-HSD1 in the guinea pig. Thus, the guinea pig provides a useful model in which the structural determinants of catalytic function of 11beta-HSD1 may be studied.

A phytoplasma related to 'Candidatus phytoplasma asteri' detected in citrus showing Huanglongbing (yellow shoot disease) symptoms in Guangdong, P. R. China

Citrus huanglongbing (HLB) or yellow shoot disease (i.e., greening disease) is highly destructive to citrus production worldwide. Understanding the etiology of HLB is critical for managing the disease. HLB is currently associated with infection by 'Candidatus Liberibacter spp.' around the world, including China. However, Koch's postulates have not been fulfilled. In addition, other plant pathogens also may be involved in HLB. In a survey performed in Guangdong Province, P. R. China in 2006 and 2007, 141 citrus samples showing typical symptoms of HLB from 11 different cities were collected. Polymerase chain reaction (PCR) using phytoplasma-specific primer sets fU5/rU3 nested with primer set P1/P7 identified 110 (78.0%) positive samples. A 1,785-bp amplicon was obtained with primer set P1/P7. Analysis showed a 100% identity of this sequence in the region of 16S rDNA and 16S-23S rRNA intergenic transcribed spacer to three strains of 'Candidatus Phytoplasma asteri' (onion yellows [Japan], aster yellows 'watercress' [Hawaii], and valeriana yellows [Lithuania]). Of the 141 samples, 89 (63.1%) samples were positive for 'Ca. Liberibacter asiaticus'. When mixed infection was considered, 69 (48.9%) samples were positive for both 'Ca. P. asteri' and 'Ca. L. asiaticus'. Transmission electron microscopy (TEM) showed low titers of both walled and wall-less bodies in the phloem sieve tubes of HLB citrus. When transmission from symptomatic citrus to periwinkle (Catharanthus roseus) via dodder (Cuscuta campestris) was conducted, both phytoplasma and 'Ca. L. asiaticus' were detected from the affected periwinkle. In addition to yellowing/mottling, the infected periwinkle showed symptoms of virescence and phyllody which are commonly associated with phytoplasmal diseases. TEM analysis of affected periwinkle revealed pleomorphic and wall-less organisms, characteristic of phytoplasmas, filling some phloem sieve tubes. In contrast, walled bacteria were at low titer. This study showed that in addition to 'Ca. L. asiaticus', a phytoplasma related to 'Ca. P. asteri' could also be detected in citrus showing HLB symptoms in Guangdong.

A study on the effect of lesions of area 7 of the parietal cortex on the short-term visual spatial memory of rhesus monkeys (Macaca mulatta)

This research is focused on the contribution of area 7 to the short-term visual spatial memory. Three rhesus monkeys (Macaca mulatta) were trained in the direct delayed response task in which 5 delay intervals were used in each session. When each monkey reached the criterion of 90% correct responses in 5 successive sessions, two monkeys underwent a surgery while the other one received a sham operation as a control. In the first stage of the surgery, bilateral areas 7a, 7b and 7ip of the parietal cortex of two monkeys were precisely lesioned. After 7 days of recuperation, the monkeys were required to do the same task. The average percentage of correct responses in the lesioned animals decreased from 94.7% to 89.3% and 93.3% to 82.0% respectively (no significance, P > 0.05, n = 2). In addition, the monkeys' complex movements were mildly impaired. The lesioned monkeys were found to have difficulty picking up food from the wells. In the second stage, bilateral area 7m was lesioned. In the 5 postoperative sessions, the average percentage of correct responses in one monkey, with a relatively precise 7m lesion, decreased from 94.7% to 92.2% (no significance, P > 0.05), while the other monkey, with widely spread necrosis of lateral parietal cortex, showed an obvious decline in performance, but still over the chance level. After 240 trials this monkey reattained the normal criterion.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunoproteomics to identify Staphylococcus aureus antigens expressed in bovine milk during mastitis

Staphylococcus aureus is an opportunistic pathogen affecting both human and animal species. An effective vaccine to prevent S. aureus bovine disease and transmission would have positive effects on animal well-being, food production, and human health. The objective of this study was to identify multiple antigens that are immunoreactive during udder colonization and disease for exploration as vaccine antigens to prevent bovine mastitis. Staphylococcus aureus produces several cell wall-anchored and surface-associated virulence factors that play key roles in the pathogenesis of mastitis. Many of these proteins are conserved between different strains of S. aureus and represent promising vaccine candidates. We used an immunoproteomics approach to identify antigenic proteins from the surface of S. aureus. The expression of cell wall and surface proteins from S. aureus was induced under low iron conditions, followed by trypsin extraction and separation by 2-dimensional electrophoresis. The separated proteins were blotted with antibodies from mastitic bovine milk and identified by liquid chromatography-mass spectrometry. Thirty-eight unique proteins were identified, of which 8 were predicted to be surface exposed and involved in S. aureus virulence. Two surface proteins, iron-regulated surface determinant protein C (IsdC) and ESAT-6 secretion system extracellular protein (EsxA), were cloned, expressed, and purified from Escherichia coli for confirmation of immune reactivity by ELISA. A PCR of 37 bovine S. aureus isolates indicated that the presence of esxA and isdC is conserved, and amino acid alignments revealed that IsdC and EsxA sequences are highly conserved. The immunoproteomics technique used in this study generated reproducible results and identified surface exposed and reactive antigens for further characterization.

CCAAT enhancer binding protein β promotes tumor growth and inhibits apoptosis in prostate cancer by methylating estrogen receptor β

The CCAAT enhancer binding protein β (C/EBPβ) is overexpressed at late stages in carcinogenesis of prostate cancer (PCa), suggesting that it could potentially contribute to progression of PCa. Estrogen receptor beta (ERβ) is a tumor suppressor gene in PCa. However, whether C/EBPβ could regulate ERβ by promoter methylation is still poorly understood.In this study, expression levels of C/EBPβ and ERβ in two PC lines (LNCap and PC-3), prostatic epithelial cell line (RWPE-1), forty-eight paired non-cancerous and cancerous peripheral blood samples were examined via qRT-PCR, western blotting and methylation-specific PCR. In addition, PCa cell line was infected with pCDH-C/EBPβ and pLKO.1-C/EBPβ and expression levels of C/EBPβ, ERβ and DNA methyltransferases were detected. Finally, the role of C/EBPβ in proliferation and apoptosis of PCa cell lines was examined by MTT and flow cytometer assay. Our results show a higher frequency of promoter methylation of ERβ levels in blood samples from PCa patients (16 of 48 cases) compared with that from healthy controls (3 of 48). Besides, elevated expression levels of C/EBPβ were found in PCa patients and two PCa lines (LNCap and PC-3) compared to non-cancerous cases or prostatic epithelial cell line (RWPE-1), while opposite expression levels of ERβ were found. Overexpression of C/EBPβ could regulate ERβ expression, DNA methyltransferases expression, cell proliferation and apoptosis. Our results support the conclusion that C/EBPβ down-regulated ERβ expression through increasing its promoter methylation, and then regulated proliferation and apoptosis in PCa.

[Spectroscopic diagnostic of atmospheric pressure argon microwave induced plasma]

Atmospheric argon microwave-induced plasma (Ar-MIP) sustained by a surfatron was obtained. Emission spectra and characteristics of argon metastable (1Sj) were studied with an optical multichannel analyer (OMA-3, 1460) under different experimental condition. Excitation mechanism of the plasma was discussed.

[The application of intracoronary stenting to type B and C lesions of coronary arteries]

Intracoronary stenting was introduced to 4 lesions due to coronary arterial dissections and to 2 lesions owing to elastic recoil of coronary arteries and stent placement was directly performed in 6 complex coronary lesions after 12 target lesions from 7 patients with Types B and C lesions of coronary arteries had been pre-dilated with balloon. Coronary angiography showed that dissections and recoils had disappeared. Target lesions were well dilated and blood flow was well improved in all cases, one patient was complicated with hemorrhage which was cured quickly. During the follow-up period of 1 to 24 months, another case had recurrence of angina after 2 months of stenting which could be controlled with anti-angina agents. These indicate that intracoronary stenting had good therapeutic effect and is considered as a safe, fast and effective method in dealing with acute complications of coronary artery after routine PTCA.

[Effect of emergency thoracic endovascular aortic repair in patients with acute traumatic thoracic aortic injury]

Objective: To investigate the effect of emergency thoracic endovascular aortic repair (TEVAR) in patients with acute traumatic thoracic aortic injury. Method: From January 2014 to December 2016, a total of 35 patients with acute traumatic thoracic aortic injuries were treated with emergency TEVAR in our hospital, their clinical data were analyzed retrospectively in this study. Results: The patients were 42 (34, 55) years old,and there were 31 males.All cases were diagnosed by emergency aorta computed tomography angiography (CTA),and 5 cases were diagnosed as aortic transaction, 13 cases were diagnosed as aortic pseudoaneurysm, 7 cases were diagnosed as aortic dissection, and 10 cases were diagnosed as aortic intramural hematoma combined hemothorax.The concomitant injuries included cerebral contusion (3 cases, 8.6%), pulmonary contusion with rib fracture (31 cases, 88.5%), long bone fracture (7 cases, 22.5%), contusion of viscera or internal organs (3 cases, 8.6%).Emergency TEVAR were performed with vascular suture system preset under local anesthesia after diagnosis,and combined injury was treated in related departments.CTA was repeated after 1, 3 and 6 months and yearly thereafter. One patient died before transferring to catheter room,and 34 (97.1%) patients underwent TEVAR procedure successfully.Time from door to operating room was (88.6±26.6) minutes,and the procedure time was (52.0±9.4) minutes. A total of 69 Perclose Proglide vascular suture system were used,and 2 cases underwent surgical suture because of hematoma and pseudoaneurysm formation in femoral arteries.The involved length of thoracic aorta was (44.5±7.4)mm. A total of 46 stent-grafts were implanted, the length of stent-graft was (164.3±15.2)mm,and the proximal oversize rate was (22.3±8.6)%. The follow-up time was 24 (12,24) months, and there were no procedure related complication such as endoleak and paraplegia. Complete aortic remodeling was observed in 14 cases. Fully thrombolization at stent segments were observed in 7 cases. Fully thrombalization of pseudoaneurysms were observed in 13 cases. One patient complained mild left upper limb weakness due to left subclavian artery occlusion. Conclusion: Emergency TEVAR is safe and effective procedure for the treatment of patients with acute traumatic thoracic aortic injury.

[Current situation of screening, prevention and treatment of bleeding esophageal varices in cirrhotic portal hypertension in Tibet region: a multicenter study]

Objective: To investigate and analyze the current situation, screening, clinical characteristics, prevention and treatment of bleeding esophageal varices in cirrhotic patients with portal hypertension in Tibet region. Methods: Clinical data of cirrhotic patients with portal hypertension through March 2017 to February 2020 from Tibet region were collected and analyzed retrospectively. Results: 511 cases with liver cirrhosis were included in the study, of which 185 cases (36.20%) had compensated cirrhosis and 326 cases (63.80%) had decompensated cirrhosis. Further analysis of the etiological data of liver cirrhosis showed that 306 cases (59.88%) were of chronic hepatitis B, 113 cases (22.11%) of alcoholic liver disease, and 68 cases (13.31%) of chronic hepatitis B combined with alcoholic liver disease. Among patients with compensated liver cirrhosis, 48 cases (25.95%) underwent endoscopic examination of which 33 diagnosed as high-risk variceal bleeding. However, none of these 33 cases had received non-selective β-blocker therapy, and only four patients had received endoscopic variceal banding therapy. Among patients with decompensated liver cirrhosis, 83 cases (25.46%) had a history of upper gastrointestinal bleeding, 297 cases (91.10%) had ascites, 23 cases (7.05%) had hepatic encephalopathy, and 3 cases (0.92%) had hepatorenal syndrome. Among the patients with a history of upper gastrointestinal bleeding, 42 cases (50.60%) had received secondary preventive treatment for bleeding esophageal varices, including 39 cases of endoscopic treatment, 1 case of endoscopic combined drug treatment, 3 cases of interventional treatment, and 2 cases of surgical treatment. Conclusion: Chronic hepatitis B and alcoholic liver diseases are the main causes of liver cirrhosis in Tibet region. Moreover, this region lacks screening, prevention and treatment for bleeding esophageal varices in cirrhotic patients with portal hypertension. Therefore, it is necessary to increase the screening of high-risk groups to prevent and improve the first-time bleeding, and promote multidisciplinary team to prevent and treat re-bleeding.