Novel regulatory mechanism in human urinary bladder: central role of transient receptor potential melastatin 4 channels in detrusor smooth muscle function.

Transient receptor potential melastatin 4 (TRPM4) channels are Ca(2+)-activated nonselective cation channels that have been recently identified as regulators of detrusor smooth muscle (DSM) function in rodents. However, their expression and function in human DSM remain unexplored. We provide insights into the functional role of TRPM4 channels in human DSM under physiological conditions. We used a multidisciplinary experimental approach, including RT-PCR, Western blotting, immunohistochemistry and immunocytochemistry, patch-clamp electrophysiology, and functional studies of DSM contractility. DSM samples were obtained from patients without preoperative overactive bladder symptoms. RT-PCR detected mRNA transcripts for TRPM4 channels in human DSM whole tissue and freshly isolated single cells. Western blotting and immunohistochemistry with confocal microscopy revealed TRPM4 protein expression in human DSM. Immunocytochemistry further detected TRPM4 protein expression in DSM single cells. Patch-clamp experiments showed that 9-phenanthrol, a selective TRPM4 channel inhibitor, significantly decreased the transient inward cation currents and voltage step-induced whole cell currents in freshly isolated human DSM cells. In current-clamp mode, 9-phenanthrol hyperpolarized the human DSM cell membrane potential. Furthermore, 9-phenanthrol attenuated the spontaneous phasic, carbachol-induced and nerve-evoked contractions in human DSM isolated strips. Significant species-related differences in TRPM4 channel activity between human, rat, and guinea pig DSM were revealed, suggesting a more prominent physiological role for the TRPM4 channel in the regulation of DSM function in humans than in rodents. In conclusion, TRPM4 channels regulate human DSM excitability and contractility and are critical determinants of human urinary bladder function. Thus, TRPM4 channels could represent promising novel targets for the pharmacological or genetic control of overactive bladder.

Large-conductance voltage- and Ca2+-activated K+ channel regulation by protein kinase C in guinea pig urinary bladder smooth muscle.

Large-conductance voltage- and Ca(2+)-activated K(+) (BK) channels are critical regulators of detrusor smooth muscle (DSM) excitability and contractility. PKC modulates the contraction of DSM and BK channel activity in non-DSM cells; however, the cellular mechanism regulating the PKC-BK channel interaction in DSM remains unknown. We provide a novel mechanistic insight into BK channel regulation by PKC in DSM. We used patch-clamp electrophysiology, live-cell Ca(2+) imaging, and functional studies of DSM contractility to elucidate BK channel regulation by PKC at cellular and tissue levels. Voltage-clamp experiments showed that pharmacological activation of PKC with PMA inhibited the spontaneous transient BK currents in native freshly isolated guinea pig DSM cells. Current-clamp recordings revealed that PMA significantly depolarized DSM membrane potential and inhibited the spontaneous transient hyperpolarizations in DSM cells. The PMA inhibitory effects on DSM membrane potential were completely abolished by the selective BK channel inhibitor paxilline. Activation of PKC with PMA did not affect the amplitude of the voltage-step-induced whole cell steady-state BK current or the single BK channel open probability (recorded in cell-attached mode) upon inhibition of all major Ca(2+) sources for BK channel activation with thapsigargin, ryanodine, and nifedipine. PKC activation with PMA elevated intracellular Ca(2+) levels in DSM cells and increased spontaneous phasic and nerve-evoked contractions of DSM isolated strips. Our results support the concept that PKC activation leads to a reduction of BK channel activity in DSM via a Ca(2+)-dependent mechanism, thus increasing DSM contractility.

Novel role for the transient potential receptor melastatin 4 channel in guinea pig detrusor smooth muscle physiology.

Members of the transient receptor potential (TRP) channel superfamily, including the Ca(2+)-activated monovalent cation-selective TRP melastatin 4 (TRPM4) channel, have been recently identified in the urinary bladder. However, their expression and function at the level of detrusor smooth muscle (DSM) remain largely unexplored. In this study, for the first time we investigated the role of TRPM4 channels in guinea pig DSM excitation-contraction coupling using a multidisciplinary approach encompassing protein detection, electrophysiology, live-cell Ca(2+) imaging, DSM contractility, and 9-phenanthrol, a recently characterized selective inhibitor of the TRPM4 channel. Western blot and immunocytochemistry experiments demonstrated the expression of the TRPM4 channel in whole DSM tissue and freshly isolated DSM cells with specific localization on the plasma membrane. Perforated whole cell patch-clamp recordings and real-time Ca(2+) imaging experiments with fura 2-AM, both using freshly isolated DSM cells, revealed that 9-phenanthrol (30 µM) significantly reduced the cation current and decreased intracellular Ca(2+) levels. 9-Phenanthrol (0.1-30 µM) significantly inhibited spontaneous, 0.1 µM carbachol-induced, 20 mM KCl-induced, and nerve-evoked contractions in guinea pig DSM-isolated strips with IC50 values of 1-7 µM and 70-80% maximum inhibition. 9-Phenanthrol also reduced nerve-evoked contraction amplitude induced by continuous repetitive electrical field stimulation of 10-Hz frequency and shifted the frequency-response curve (0.5-50 Hz) relative to the control. Collectively, our data demonstrate the novel finding that TRPM4 channels are expressed in guinea pig DSM and reveal their critical role in the regulation of guinea pig DSM excitation-contraction coupling.

TRPM4 channel: a new player in urinary bladder smooth muscle function in rats.

The TRPM4 channel is a Ca(2+)-activated, monovalent cation-selective channel of the melastatin transient receptor potential (TRPM) family. The TRPM4 channel is implicated in the regulation of many cellular processes including the immune response, insulin secretion, and pressure-induced vasoconstriction of cerebral arteries. However, the expression and function of the TRPM4 channels in detrusor smooth muscle (DSM) have not yet been explored. Here, we provide the first molecular, electrophysiological, and functional evidence for the presence of TRPM4 channels in rat DSM. We detected the expression of TRPM4 channels at mRNA and protein levels in freshly isolated DSM single cells and DSM tissue using RT-PCR, Western blotting, immunohistochemistry, and immunocytochemistry. 9-Hydroxyphenanthrene (9-phenanthrol), a novel selective inhibitor of TRPM4 channels, was used to examine their role in DSM function. In perforated patch-clamp recordings using freshly isolated rat DSM cells, 9-phenanthrol (30 µM) decreased the spontaneous inward current activity at -70 mV. Real-time DSM live-cell Ca(2+) imaging showed that selective inhibition of TRPM4 channels with 9-phenanthrol (30 µM) significantly reduced the intracellular Ca(2+) levels. Isometric DSM tension recordings revealed that 9-phenanthrol (0.1-30 µM) significantly inhibited the amplitude, muscle force integral, and frequency of the spontaneous phasic and pharmacologically induced contractions of rat DSM isolated strips. 9-Phenanthrol also decreased the amplitude and muscle force integral of electrical field stimulation-induced contractions. In conclusion, this is the first study to examine the expression and provide evidence for TRPM4 channels as critical regulators of rat DSM excitability and contractility.

Predictors of support for juvenile sex offender registration: educated individuals recognize the flaws of juvenile registration.

We investigated demographic predictors of support for juvenile sex offender registration policies, including education level, gender, political orientation, and age. Participants were 168 individuals recruited from public places in a Midwest community (45% women; M age = 42). In line with hypotheses, as education level increased, support for juvenile registration decreased, as did the belief that juvenile registration protects the community. In addition, as education level increased, belief that the juvenile understood his actions decreased, as did support for juvenile registration when it is framed as ineffective at reducing sex crime. These beliefs mediated the relationship between education level and diminished support for juvenile registration. Implications of these results for the advancement of effective juvenile sex offender policy are discussed.

A Novel Approach to Improve Newborn Screening for Congenital Hypothyroidism by Integrating Covariate-Adjusted Results of Different Tests into CLIR Customized Interpretive Tools.

Newborn screening for congenital hypothyroidism remains challenging decades after broad implementation worldwide. Testing protocols are not uniform in terms of targets (TSH and/or T4) and protocols (parallel vs. sequential testing; one or two specimen collection times), and specificity (with or without collection of a second specimen) is overall poor. The purpose of this retrospective study is to investigate the potential impact of multivariate pattern recognition software (CLIR) to improve the post-analytical interpretation of screening results. Seven programs contributed reference data (N = 1,970,536) and two sets of true (TP, N = 1369 combined) and false (FP, N = 15,201) positive cases for validation and verification purposes, respectively. Data were adjusted for age at collection, birth weight, and location using polynomial regression models of the fifth degree to create three-dimensional regression surfaces. Customized Single Condition Tools and Dual Scatter Plots were created using CLIR to optimize the differential diagnosis between TP and FP cases in the validation set. Verification testing correctly identified 446/454 (98%) of the TP cases, and could have prevented 1931/5447 (35%) of the FP cases, with variable impact among locations (range 4% to 50%). CLIR tools either as made here or preferably standardized to the recommended uniform screening panel could improve performance of newborn screening for congenital hypothyroidism.

Effects of defendant and victim race on perceptions of juvenile sex offenders.

We investigated effects of defendant race, victim race, and juror gender on public perceptions of a juvenile sex offense. We predicted that participants, particularly men, would support registering a juvenile defendant as a sex offender more when he was Black than White and that participants, particularly women, would support registering the defendant more when the female crime victim was portrayed as White than as Black. We also expected that support for registration would be higher when the defendant and victim were different races than when they were the same race. As expected, women (but not men) recommended registration more when the victim was White than Black. Further, participants supported registration more when the defendant and the victim were different races than when they were the same race. These effects were mediated by retributive goals to punish the offender-not by utilitarian goals to protect society. Explanations and implications are discussed.

Strengthening role clarity in acute care nurse case managers: application of the synergy model in staff development.

PURPOSE OF STUDY: The purpose of this quality improvement study was to evaluate the impact of a novel educational intervention on nurse case managers' (NCMs') perceived role ambiguity, role conflict, and use of nursing competencies. Specific aims were to apply the American Association of Critical-Care Nurses Synergy Model for Patient Care to determine the use of the model's nurse competencies in acute care case management, to pilot test the feasibility of using widely available basic computer technologies to facilitate NCMs' orientation in acute care settings, and to establish the foundation for future work in developing an evidence-based orientation program for new NCMs based on a nursing conceptual framework. PRIMARY PRACTICE SETTINGS: Two acute care community hospitals in northeastern Ohio, both part of a large national hospital corporation. METHODOLOGY AND SAMPLE: The sample consisted of NCMs who were actively employed in 1 of 2 acute care hospitals and voluntarily agreed to participate in this quality improvement study. Data on perceived role conflict and role ambiguity, perceived use of nurse competencies in bedside nursing and in case management, demographics, and evaluative feedback were collected using Google Docs. The intervention consisted of a series of four self-paced computer-based learning modules that provided participants with an introduction to acute care nursing case management based on the American Association of Critical-Care Nurses Synergy Model. RESULTS: Four of the 6 role ambiguity subscale item scores revealed reductions in role ambiguity after the educational intervention. A statistically significant decrease in one role conflict item was observed. Participants rated the use of all nurse competencies as higher in case management than in bedside nursing practice; the variance between the two further increased after the intervention. Statistically significant differences in the use of clinical judgment, advocacy/moral agency, and caring practices were identified. Participants reported that the educational content would be valuable for new NCMs transitioning from bedside clinical practice. The addition of case studies or clinical scenarios illustrating each nurse competency was suggested. Testing of the Synergy Model-based education modules with novice case managers actively transitioning from the bedside to a case management role will be the next step in the development of this program. IMPLICATIONS FOR CASE MANAGEMENT PRACTICE: : The use of widely available computer technologies to deliver introductory case management orientation content is feasible, although conversion to a web-based platform is recommended. Evidence-based strategies to prepare NCMs for expanded competency in clinical judgment, advocacy/moral agency, and caring practices are needed.

Control of urinary bladder smooth muscle excitability by the TRPM4 channel modulator 9-phenanthrol.

The Ca (2+)-activated monovalent cation selective transient receptor potential melastatin 4 (TRPM4) channel has been recently identified in detrusor smooth muscle (DSM) of the urinary bladder. Two recent publications by our research group provide evidence in support of the novel hypothesis that TRPM4 channels enhance DSM excitability and contractility. This is a critical question as prior studies have primarily targeted hyperpolarizing currents facilitated by K(+) channels, but the depolarizing component in DSM cells is not well understood. For the first time, we utilized the selective TRPM4 channel inhibitor, 9-phenanthrol, to investigate TRPM4 channel functional effects in DSM at both cellular and tissue levels in rodents. Our new data presented here showed that in rat DSM cells, 9-phenanthrol attenuates spontaneous inward currents in the presence of the muscarinic receptor agonist, carbachol, thus reducing DSM cell excitability. In support of our original hypothesis, we found that TRPM4 channel mRNA levels are much higher in DSM vs. vascular smooth muscle and that inhibition of TRPM4 channels can potentially attenuate DSM excitability. Thus, we postulate the novel concept that selective pharmacological inhibition of TRPM4 channels can limit both excitability and contractility of DSM.

Role ambiguity and role conflict in nurse case managers: an integrative review.

PURPOSE/OBJECTIVES: The purpose of this integrative review is to critically examine the relationship between the transition from a direct caregiver to a nurse case manager role and the perceived levels of role ambiguity and role conflict. PRIMARY PRACTICE SETTING(S): Nurse case managers in acute care, postacute care, and managed care settings. FINDINGS/CONCLUSIONS: Nurses can expect to experience substantial role ambiguity and role conflict as they take on the case manager role, primarily because of inadequate role definition, unexpected ethical challenges, and lack of prior insight into the case manager role. Role ambiguity and role conflict may impact nurse case managers' job satisfaction and job performance. IMPLICATIONS FOR CASE MANAGEMENT PRACTICE: Well-designed broad-scale descriptive studies are needed to further explicate the relationship between transition from direct caregiver to nurse case manager roles and the experience of role ambiguity and role conflict. Nurses transitioning from direct caregiver to nurse case manager roles should be systematically prepared to identify and manage specific ethical challenges commonly encountered by case managers. Further development of a nursing theoretical foundation for case management would be very useful in helping caregivers understand that as case managers, they remain practicing nurses with all the inherent rights and responsibilities of professional nursing.