Ex Vivo Smooth Muscle Pharmacological Effects of a Novel Bradykinin-Related Peptide, and Its Analogue, from Chinese Large Odorous Frog, Odorrana livida Skin Secretions

Bradykinin-related peptides (BRPs) are one of the most extensively studied frog secretions-derived peptide families identified from many amphibian species. The diverse primary structures of BRPs have been proven essential for providing valuable information in understanding basic mechanisms associated with drug modification. Here, we isolated, identified and characterized a dodeca-BRP (RAP-L1, T6-BK), with primary structure RAPLPPGFTPFR, from the skin secretions of Chinese large odorous frogs, Odorrana livida. This novel peptide exhibited a dose-dependent contractile property on rat bladder and rat ileum, and increased the contraction frequency on rat uterus ex vivo smooth muscle preparations; it also showed vasorelaxant activity on rat tail artery smooth muscle. In addition, the analogue RAP-L1, T6, L8-BK completely abolished these effects on selected rat smooth muscle tissues, whilst it showed inhibition effect on bradykinin-induced rat tail artery relaxation. By using canonical antagonist for bradykinin B1 or B2 type receptors, we found that RAP-L1, T6-BK -induced relaxation of the arterial smooth muscle was very likely to be modulated by B2 receptors. The analogue RAP-L1, T6, L8-BK further enhanced the bradykinin inhibitory activity only under the condition of co-administration with HOE140 on rat tail artery, suggesting a synergistic inhibition mechanism by which targeting B2 type receptors.

Role of Vascular Smooth Muscle Cell PiT-2 in Basal Ganglia Calcification

Thesis (Master's)--University of Washington, 2016-08

Motivating residents to combat invasive species on private lands: social norms and community reciprocity

Invasive species (IS) threaten biodiversity and ecosystem functioning. To achieve landscape-scale reductions in IS and the associated gains for biodiversity, IS control efforts must be expanded across private lands. Enhancing IS control across private lands requires an understanding of the factors that motivate residents to engage or prohibit residents from engaging in efforts to control IS. Drawing from the collective interest model and literature, we sought to understand how a wide range of interpersonal, intrapersonal, and contextual factors might influence resident action around combating the invasive tree albizia (Falcataria moluccana), in the Puna District of Hawaiʻi. To do so, we used a cross-sectional survey of 243 residents and elastic net regression techniques. We found that residents’ actions related to IS control were related to their perceptions of social norms and community reciprocity regarding albizia control, as well as their knowledge of effective control strategies and their risk perceptions regarding albizia. These findings suggest that, although common intervention approaches that focus on providing education or subsidies are important, they may be more effective at reducing the spread of IS if coupled with approaches that build community reciprocity and norms.

The Role of Feminine and Masculine Norms in College Women's Alcohol Use

Current literature suggests not only that men and women can conform to both feminine and masculine norms, but that women who adhere to certain masculine norms may be at greater risk for problematic alcohol use. This study examined conformity to both masculine and feminine norms, and how conformity to distinct norms influenced heavy episodic drinking and alcohol-related problems among a sample of underage college women (N= 645). Results demonstrated that the masculine norms risk-taking and emotional control were associated with increased HED, while the masculine norm power over women was associated with a decrease in HED. Traditional feminine norms, including modesty and sexual fidelity, were associated with a decrease in HED and alcohol-related problems. The feminine norm relational was associated with increased HED, while the norms thinness and appearance were associated with increased alcohol-related problems. The study’s theoretical and clinical implications are discussed.

Smooth regular neighborhoods

If K is a subcomplex of a smooth triangulation of a manifold M and N is a regular neighborhood of K contained in an open neighborhood U of K in M, there is a piecewise regular homeomorphism f of M carrying N onto a smooth submanifold of U, and f reduces to the identity map on K and outside U.

Internal mammary artery smooth muscle cells resist migration and possess high antioxidant capacity

Objective- This study investigated whether differences exist in atherogen-induced migratory behaviors and basal antioxidant enzyme capacity of vascular smooth muscle cells (VSMC) from human coronary (CA) and internal mammary (IMA) arteries. Methods- Migration experiments were performed using the Dunn chemotaxis chamber. The prooxidant [NAD(P)H oxidase] and antioxidant [NOS, superoxide dismutase, catalase and glutathione peroxidase] enzyme activities were determined by specific assays. Results- Chemotaxis experiments revealed that while both sets of VSMC migrated towards platelet-derived growth factor-BB (1-50 ng/ml) and angiotensin II (1-50 nM), neither oxidized-LDL (ox-LDL, 25-100 �g/ml) nor native LDL (100 �g/ml) affected chemotaxis in IMA VSMC. However, high dose ox-LDL produced significant chemotaxis in CA VSMC that was inhibited by pravastatin (100 nM), mevastatin (10 nM), losartan (10 nM), enalapril (1 �M), and MnTBAP (a free radical scavenger, 50��M). Microinjection experiments with isoprenoids i.e. geranylgeranylpyrophosphate (GGPP) and farnesylpyrophosphate (FPP) showed distinct involvement of small GTPases in atherogen-induced VSMC migration. Significant increases in antioxidant enzyme activities and nitrite production along with marked decreases in NAD(P)H oxidase activity and O2 .- levels were determined in IMA versus CA VSMC. Conclusions- Enhanced intrinsic antioxidant capacity may confer on IMA VSMC resistance to migration against atherogenic agents. Drugs that regulate ox-LDL or angiotensin II levels also exert antimigratory effects.

A study of the electrical basis for the inhibition and excitation in autonomically innervated smooth muscle

The aim of this thesis was to investigate the electrical and mechanical responses to inhibitory non-adrenergic noncholinergic (NANC) nerve stimulation in the bovine retractor penis muscle (BRP) and compare them with those to an inhibitory extract made from this muscle. The extract may contain the NANC inhibitory transmitter of the BRP and possibly of other smooth muscles. Because of species differences in the electrical response to NANC nerves in the rat and rabbit anococcygeus the effects of the extract on these tissues was also investigated. Prior to the investigation of the extract, both the excitatory and inhibitory responses to field stimulation in the BRP, and the effects of passive membrane potential displacement were studied using conventional intra- or extracellular (sucrose gap) recording techniques. The majority of cells in the BRP were electrically quiescent independent of the resting tone. The most frequent (in approximately 25% of preparations) form of spontaneous activity, oscillations in membrane potential and tone, may represent a pacemaker activity. The BRP had cable properties; the time constant and space constant indicated a high membrane resistance. In the absence of tone, field stimulation of the BRP evoked excitatory junction potentials (ejps) in every cell impaled and contractions, graded with the strength, frequency and number of pulses; spikes were not observed. Guanethidine (1-3 x 10-5M) abolished the ejps and contractions, confirming their adrenergic origin. Noradrenaline added exogenously depolarised and contracted the muscle. These effects were blocked by the a-adrenoceptor antagonists, phentolamine and prazosin. However, phentolamine (2.5x 10-6M) inhibited the contraction without reducing the ejp significantly. These effects may be independent of adrenoceptor blockade or the ejp may be mediated by a substance other than noradrenaline (e.g. ATP) released from adrenergic nerves. Prazosin (1.4 x lO-6M) failed to block either the ejp or contraction, indicating the possible existence of two types of adrenoceptor in the BRP; one activated by neuronally-released and the other by exogenously-added noradrenaline. ATP, a contaminant in the extract, also depolarised and contracted the BRP. Physostigmine reduced whilst atropine enhanced the ejps and contractions without similarly affecting the response to exogenous noradrenaline. This confirmed the presence of a cholinergic inhibitory innervation acting on the excitatory adrenergic fibres (Klinge and Sjostrand, 1977). TEA (1 x lO-4M) enhanced the ejp and contraction. Higher concentrations (0.5 to 10 x 10-3M) depolarised, increased the tone and evoked electrical and mechanical oscillations but no spikes. The depolarisation and contraction to exogenous noradrenaline were not enhanced, indicating that TEA acts on the adrenergic nerves. Some post-synaptic effect to block K+ channels also seems likely. The relationship between ejp amplitude and membrane potential in the double sucrose gap was linear and indicated a reversal potential more positive than -30mV. Electrotonic pulse amplitude decreased during the ejp, indicating an increased membrane conductance. Ejps and contractions were reduced following the replacement of the NaCl of the Krebs solution with sodium glutamate. This may be due to the effects of glutamate itself (e.g. Ca2+ chelation) rather than reduction in the membrane Cl- gradient. Tone usually developed spontaneously and was accompanied by membrane depolarisation (from -53 to -45mV) which may open voltage-dependent channels, causing Ca2+ entry and/or its release from intracellular binding sites. Field stimulation produced inhibitory potentials (ijps) and relaxations graded with the strength and number of pulses but showing little frequency dependence. Rebound depolarisation and contraction often followed the ijp and relaxation. Tetrodotoxin (3 x IO-6M), but not adrenergic or cholinergic antagonists, abolished the ijp and relaxation, confirming their non-adrenergic non-cholinergic neurogenic nature. The extract, prepared and acid-activated as described by Gillespie, Hunter and Martin (1981), hyperpolarised and relaxed the BRP, as did sodium nitroprusside and adenosine triphosphate (ATP). Unlike the activated extract or sodium nitroprusside, desensitisation to ATP occurred rapidly and without any change in the inhibitory electrical or mechanical responses to field stimulation. The ijp and relaxation in the BRP were insensitive to apamin but abolished by oxyhaemoglobin (4-8 x 10-6M), as were the responses to extract and sodium nitroprusside. In TEA (10-2M), field stimulation evoked relaxations with no accompanying electrical change. The ijp may be unconnected with or additional to another mechanism producing relaxation. The relationship between membrane potential and ijp in the BRP was non-linear. Ijp amplitude was initially increased during membrane potential displacement from -45mV to approximately -60mV. Thereafter (-60 to -l03mV) the ijp was reduced. Ijps were abolished at -27 and -103mV; reversal was not observed. The hyperpolarisation to extract was also enhanced during passive displacement of the membrane potential to more negative values (-57mV). Membrane resistance increased during the ijp. The extract produced inconsistent changes in membrane resistance, possibly because of the presence of more than one active component. K+ withdrawal failed to enhance the ijp or hyperpolarisation to extract and 20mM K+ did not abolish the the ijp at membrane potentials exceeding EK (-49mV). Thus, the ijp or hyperpolarisation to extract are unlikely to be mediated by an increased K+ conductance. Reducing the Cl- abolished the hyperpolarisation to field stimulation and extract. This occurred more quickly than the anticipated reduction in the Cl- gradient and may be due to Ca2+ chelation by the anion substitute (glutamate or benzenesulphonate) or blockade of the resting conductance which is normally inactivated by the transmitter. Ouabain (1-5x 10-5M), which reduces both the Na+ and Cl- gradients, abolished the ijp, implicating either of these ions as the ionic species involved. In the rat and rabbit anococcygeus, field stimulation and extract each reduced guanethidine-induced tone. This was unaccompanied in the majority of cells in the rat by any significant electrical response. In the remaining cells, inhibition of the membrane potential oscillations occurred. The rabbit anococcygeus differed in that inhibition of the electrical oscillations was observed in every cell exhibiting this behaviour. However, the majority of cells in the rabbit were electrically quiescent and showed only small hyperpolarisations to field stimulation and no electrical response to extract. Apamin (1 x 10-7M) failed to block the electrical and mechanical response to field stimulation in the rabbit but did inhibit transiently that to extract. The latter effect may be due to the initial excitatory effects of apamin. The similarities between the electrical effects of the extract and those of inhibitory nerve stimulation in the BRP, rat and rabbit anococcygeus muscles are generally consistent with their being mediated by the same active component. Moreover, the ijp in the BRP shows properties which have not been reported in other non-adrenergic noncholinergically innervated smooth muscles.

Differential mechanisms of angiotensin II and PDGF-BB on migration and proliferation of coronary artery smooth muscle cells

Angiotensin II (Ang II) and platelet-derived growth factor-BB (PDGF-BB) are associated with excessive cell migration, proliferation and many growth-related diseases. However, whether these agents utilise similar mechanisms to trigger vascular pathologies remains to be explored. The effects of Ang II and PDGF-BB on coronary artery smooth muscle cell (CASMC) migration and proliferation were investigated via Dunn chemotaxis assay and the measurement of [3H]thymidine incorporation rates, respectively. Both atherogens produced similar degrees of cell migration which were dramatically inhibited by mevastatin (10 nM). However, the inhibitory effects of losartan (10 nM) and MnTBAP (a free radical scavenger; 50 μM) were found to be unique to Ang II-mediated chemotaxis. In contrast, MnTBAP, apocynin (an antioxidant and phagocytic NADPH oxidase inhibitor; 500 μM), mevastatin and pravastatin (100 nM) equally suppressed both Ang II and PDGF-BB-induced cellular growth. Although atherogens produced similar changes in NADPH oxidase, NOS and superoxide dismutase activities, they differentially regulated antioxidant glutathione peroxidase activity which was diminished by Ang II and unaffected by PDGF-BB. Studies with signal transduction pathway inhibitors revealed the involvement of multiple pathways i.e. protein kinase C, tyrosine kinase and MAPK in Ang II- and/or PDGF-BB-induced aforementioned enzyme activity changes. In conclusion, Ang II and PDGF-BB may induce coronary atherosclerotic disease formation by stimulating CASMC migration and proliferation through agent-specific regulation of oxidative status and utilisation of different signal transduction pathways.

Homogenization of the p-Laplacian with nonlinear boundary condition on critical size particles: Identifying the strange term for the some non smooth and multivalued operators

We extend previous papers in the literature concerning the homogenization of Robin type boundary conditions for quasilinear equations, in the case of microscopic obstacles of critical size: here we consider nonlinear boundary conditions involving some maximal monotone graphs which may correspond to discontinuous or non-Lipschitz functions arising in some catalysis problems.

Behavioral Norms in Virtual Organizations

Part 2: Behaviour and Coordination

Romantic relationships and adjustment in early adulthood: The role of cross-sex experience in the context of social norms and support

Attachment and interpersonal theory suggest a sequential pattern of relationships beginning in the earliest stage of development and progressing to social and eventually romantic relationships. Theoretically, cross-sex experiences have an important role in the progression of interpersonal relationships. Despite the prevalence of these theories about the nature of romantic relationship development, the linkage of cross-sex experience (CSE) to romantic relationships has not been established. Indeed, it is an intuitive assumption, especially within Western society and these theories do not consider socio-cultural factors that may influence CSE and relationship satisfaction. This study addresses the varying contextual factors that may contribute to relationship satisfaction and adjustment, aside from CSE, and is divided into two parts. Study 1, addresses CSE, relationship satisfaction, and adjustment in a unique population, ultra-Orthodox Jews. Among this population, social or romantic CSE is limited and sexes are effectively segregated. Study 2, expanded the study to a larger sample of U.S. college students, to assess the linkage of CSE to romantic relationship satisfaction in a more typical Western population. It included social norm and support variables to address the contextual nature of relationship development and satisfaction. Results demonstrated clear differences in the relation between CSE and relationship satisfaction in the two samples. In the first sample CSE was unrelated to relationship satisfaction; nevertheless, relationship satisfaction was associated with adjustment as it is for more typical populations with greater CSE. These results suggested the importance of specifying how social norms and social support relate to CSE, relationship satisfaction and adjustment. The results from the second sample were consistent with the theoretical framework upon which the social/romantic literature is based. CSE was directly connected to relationship satisfaction. As anticipated, CSE, relationship satisfaction, and adjustment also varied as a function of social norms and support. These findings further validate the influence of socio-cultural factors on relationship satisfaction and adjustment. This study contributes to the romantic relationship literature and broadens our understanding of the complex nature of interpersonal and romantic relationships.^

A study of employee affective organisational commitment and retention in Pakistan:the roles of psychological contract breach and norms of reciprocity

Social exchange theory and notions of reciprocity have long been assumed to explain the relationship between psychological contract breach and important employee outcomes. To date, however, there has been no explicit testing of these assumptions. This research, therefore, explores the mediating role of negative, generalized, and balanced reciprocity, in the relationships between psychological contract breach and employees’ affective organizational commitment and turnover intentions. A survey of 247 Pakistani employees of a large public university was analyzed using structural equation modeling and bootstrapping techniques, and provided excellent support for our model. As predicted, psychological contract breach was positively related to negative reciprocity norms and negatively related to generalized and balanced reciprocity norms. Negative and generalized (but not balanced) reciprocity were negatively and positively (respectively) related to employees’ affective organizational commitment and fully mediated the relationship between psychological contract breach and affective organizational commitment. Moreover, affective organizational commitment fully mediated the relationship between generalized and negative reciprocity and employees’ turnover intentions. Implications for theory and practice are discussed.

Equivalent norms in polynomial spaces and applications.

In this paper, equivalence constants between various polynomial norms are calculated. As an application, we also obtain sharp values of the Hardy Littlewood constants for 2-homogeneous polynomials on l(p)(2) spaces, 2 < p <= infinity. We also provide lower estimates for the Hardy-Littlewood constants for polynomials of higher degrees.

Wine phenolics: looking for a smooth mouthfeel

Each grape variety has its own phenolic profile. However, the concentration of the phenolic compounds present in wine mainly dependson winemaking processes. Phenolic compounds influence wine sensorial characteristics namely taste or mouthfeel, bitterness, astringency and color. Humans can perceive six basic tastes: sweet, salty; sour; umami; fat-taste and bitter taste. This last basic taste is considered as a defense mechanism against the ingestion of potential poisons. Some of the genes,encoding G-protein-coupled receptors - TAS2Rs, which translate for these distinct bitter compounds detectors have been identified. Different phenolic compounds activate distinguished combination of TAS2Rs. Astringency in wine is primarily driven by proanthocyanidins, soluble protein-proanthocyanidins complexes which diminish the protective salivary film and bind to the salivary pellicle; insoluble protein-proanthocyanidins complex and proanthocyanidins are rejected against salivary film and trigger astringency sensation via increasing friction. Thus, the aim of this review is to expand the knowledge about the role of wine phenolic compounds in wine sensorial properties, namely in bitterness and astringency phenomenon’s.