Erk1/2 Mediates Leptin Receptor Signaling in the Ventral Tegmental Area

Leptin acts on the ventral tegmental area (VTA) to modulate neuronal function and feeding behavior in rats and mice. To identify the intracellular effectors of the leptin receptor (Lepr), downstream signal transduction events were assessed for regulation by direct leptin infusion. Phosphorylated signal transducer and activator of transcription 3 (pSTAT3) and phosphorylated extracellular signal-regulated kinase-1 and -2 (pERK1/2) were increased in the VTA while phospho-AKT (pAKT) was unaffected. Pretreatment of brain slices with the mitogen-activated protein kinase kinase -1 and -2 (MEK1/2) inhibitor U0126 blocked the leptin-mediated decrease in firing frequency of VTA dopamine neurons. The anorexigenic effects of VTA-administered leptin were also blocked by pretreatment with U0126, which effectively blocked phosphorylation of ERK1/2 but not STAT3. These data demonstrate that pERK1/2 may have a critical role in mediating both the electrophysiogical and behavioral effects of leptin receptor signaling in the VTA

Lysine-Rich Extracellular Rings Formed by hβ2 Subunits Confer the Outward Rectification of BK Channels

The auxiliary β subunits of large-conductance Ca2+-activated K+ (BK) channels greatly contribute to the diversity of BK (mSlo1 α) channels, which is fundamental to the adequate function in many tissues. Here we describe a functional element of the extracellular segment of hβ2 auxiliary subunits that acts as the positively charged rings to modify the BK channel conductance. Four consecutive lysines of the hβ2 extracellular loop, which reside sufficiently close to the extracellular entryway of the pore, constitute three positively charged rings. These rings can decrease the extracellular K+ concentration and prevent the Charybdotoxin (ChTX) from approaching the extracellular entrance of channels through electrostatic mechanism, leading to the reduction of K+ inflow or the outward rectification of BK channels. Our results demonstrate that the lysine rings formed by the hβ2 auxiliary subunits influences the inward current of BK channels, providing a mechanism by which current can be rapidly diminished during cellular repolarization. Furthermore, this study will be helpful to understand the functional diversity of BK channels contributed by different auxiliary β subunits

Assessing the Impact of a Community-Based Nutrition Education Program in the Haven Free Clinic

Abstract Background The Haven clinic is a volunteer and student-run clinic serving low-income residents of the Fair Haven community in New Haven, CT. The Advancing Nutrition and Dietary Outcomes (ANDO) program is a one-on-one counseling program for patients at risk for chronic disease. This project aimed to evaluate the ANDO program for efficacy and patient satisfaction. Methods Two main data collection methods were used to assess the efficacy and patient satisfaction with ANDO, resulting in a mixed methods analysis. A baseline survey instrument measured patient skills, knowledge and attitudes about healthy eating and physical activity. Key informant interviews gauged these same topics as well as satisfaction with the program. Results Survey results revealed a strongly positive attitude towards improving diet and increasing physical activity as ways of overcoming chronic disease. Surveys also illustrated the lack of knowledge and skills of patients to make those lifestyle changes on their own. Interviews with patients who have gone through at least one module of ANDO revealed strong satisfaction with the program, though some suggestions for improvement were made. Conclusions The ANDO program is a strong patient-focused program that reaches a portion of the target population in the Fair Haven community. Patients who enroll are satisfied with the program and offer suggestions for continued strength of the program including group sessions and consistent counselors. Evaluation team recommendations include producing a thorough program manual for more program consistency, administering pre- and post-program surveys with future patients, and conducting an evaluability assessment prior to future evaluation endeavors.https://elischolar.library.yale.edu/ysph_pbchrr/1002/thumbnail.jp

Prescribing and dispensing practices for medicines used to treat non-communicable diseases in Uganda: a cross-sectional study

Background: Non-communicable diseases (NCDs) are increasingly prevalent in low-income and middle-income countries (LMIC) and accessibility of medicines is essential for the management of these conditions. In Uganda, although many NCD medicines are now included in the national essential medicines list, sporadic evidence suggests that these medicines are widely unavailable to patients. The prescribing patterns of NCD medicines by providers and the dispensing patterns by dispensers represent important knowledge gaps in efforts to understand the care cascade for NCDs in Uganda. We aimed to describe the prescribing and dispensing practices for medicines used to treat NCDs, particularly hypertension, diabetes, and heart failure in Ugandan health-care facilities. Methods: Based on WHO methodology, we did a cross-sectional study in which systematic sampling was used to collect data from patients attending outpatient NCD clinics at 15 higher-level public health-care facilities throughout Uganda. Demographic, prescribing, and dispensing information were collected using pre-tested structured questionnaires. Prescribing information was recorded from prescriptions, and dispensing information was obtained from medicine packets. Medicine tablets were counted by data collectors. Patients who reported not receiving all of their prescribed doses were contacted by phone to determine if they obtained the non-dispensed doses elsewhere. The primary outcome, which we term the Prescribing-Dispensing (P-D) Gap, was the percentage of prescribed doses that were not dispensed. Associations were tested using a linear mixed model. Findings: We analysed data from 477 participants, of whom 454 (71%) were women. The average age was 51·4 years (SD 13·5). The mean number of drugs prescribed per encounter was 2·5 (SD 1·1), of which only 1·4 (0·9) drugs were dispensed. Overall, 82 591 total doses were prescribed, and 35 290·5 doses were dispensed, resulting in a P-D Gap of 57·3%. The P-D Gap was smaller for diabetes medicines than for medicines for cardiovascular diseases (46·2% vs 67·5%; p<0·001). 535 (84%) patients did not receive all of their prescribed doses, although only 442 (69%) patients reported having not received all prescribed doses. Of these, 317 (72%) patients were told this was because drug stocks were low. Upon follow-up, 90 (36%) of 253 patients contacted had not obtained their non-dispensed doses elsewhere. Interpretation: A large P-D Gap exists for medicines used to treat NCDs in Ugandan public health-care facilities. The P-D Gap differs by medicine class and appears to be driven by medicine availability at public sector pharmacies. Most patients do not close this gap by purchasing medicines at private pharmacies, suggesting that under-treatment of these chronic conditions is widespread in patients who are already linked to care. Future work should explore feasible approaches to decrease this P-D Gap. Funding: Doris Duke Clinical Research Fellowship

Preparation of 5-(1,1'-biphenyl)-4-yl-5-(4-(4-aminoacylphenyl)-piperazin)-1-yl-pyrimidine-2,4,6-triones and their use as inhibitors of zinc metalloendopeptidases

publication date: 2006-03-02; filing date: 2004-08-2

Single-channel conductance of mSlo1+hβ2 and mSlo1+4K4D.

<p>A–B, Three consecutive traces at the upper panel show the single-channel openings from inside-out patches from <i>Xenopus oocytes</i> injected with the cRNA encoding mSlo1+hβ2 or mSlo1+4K4D subunits as indicated. Channels were activated by a voltage step to +100 mV after a prepulse to −180 mV to remove inactivation, in the presence of 10 µM Ca²⁺. Average traces of each channel derived from 50 sweeps are shown below the traces. The inactivation time constants of mSlo1+hβ2 and mSlo1+4K4D are 10.9 ms and 10.1 ms at +100 mV, respectively. Single-channel openings at a voltage of +100 mV and −100 mV are shown in the lower panel. D, Single-channel currents were plotted as function of membrane potentials for mSlo1+hβ2 (empty circle), mSlo1+4K4D (solid circle) and mSlo1 (empty triangle). The rectification ratios (R) of mSlo1+hβ2 and mSlo1+4K4D are 1.81±0 .05 (n = 4) and 1.13±0.05 (n = 4), respectively.</p

Basic amino acids of hβ2 extracellular domain contribute to the outward rectification of BK channels.

<p>A. The representative traces are for mSlo1+K137A, mSlo1+K141A, mSlo1+K147A and mSlo1+K150A as indicated. The voltage protocol is the same as shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0002114#pone-0002114-g001" target="_blank">Fig. 1A</a>. Scale bars represent 10 ms and 5 nA, respectively. B. The instantaneous tail currents from the top to the bottom are for mSlo1+K137A, mSlo1+K141A, mSlo1+K147A and mSlo1+K150A, respectively. The voltage protocol is the same as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0002114#pone-0002114-g001" target="_blank">Fig. 1B</a>. Scale bars represent 10 ms and 5 nA, respectively. C. The instantaneous I-V curves normalized to the tail currents at +100 mV are for mSlo1+K137A, mSlo1+K141A, mSlo1+K147A and mSlo1+K150A as indicated. The long dash and the dotted line are for mSlo1+hβ2 and mSlo1, respectively. D. The rectification ratios R = |I₁₀₀/I₋₁₀₀| were plotted for mSlo1, mSlo1+hβ2, mSlo1+K137A, mSlo1+K141A, mSlo1+K147A and mSlo1+K150A as indicated. They are 1.22±0.04 (n = 8) and 1.81±0.06 (n = 17), 1.36±0.05 (n = 11), 1.51±0.03 (n = 15), 1.53±0.04 (n = 14) and 1.74±0.04 (n = 12) for mSlo1, mSlo1+hβ2, mSlo1+K137A, mSlo1+K141A, mSlo1+K147A and mSlo1+K150A, respectively.</p

The multi-lysine mutations of hβ2 alleviate the outward rectification of BK channels.

<p>A. The representative traces are for mSlo1+2K2A, mSlo1+3K3A, mSlo1+4K4A and mSlo1+4K4D, respectively. Here, the 2K2A, 3K3A, 4K4A and 4K4D are short for K137AK141A, K137AK141AK147A, K137AK141AK147AK150A and K137DK141DK147DK150D, respectively. The voltage protocol is the same as shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0002114#pone-0002114-g001" target="_blank">Fig. 1A</a>. Scale bars represent 10 ms and 5 nA, respectively. B. The instantaneous tail currents from the top to the bottom are for mSlo1+2K2A, mSlo1+3K3A, mSlo1+4K4A, mSlo1+4K4D and mSlo1+4K4R, respectively. The voltage protocol is the same as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0002114#pone-0002114-g001" target="_blank">Fig. 1B</a>. Scale bars represent 10 ms and 5 nA, respectively. C. The instantaneous I-V curves normalized to the tail currents at +100 mV are for mSlo1+2K2A, mSlo1+3K3A, mSlo1+4K4A, mSlo1+4K4D and mSlo1+4K4R as indicated. The long dash and the dotted line are for mSlo1+hβ2 and mSlo1, respectively. D. The rectification ratios R = |I₁₀₀/I₋₁₀₀| were plotted for mSlo1, mSlo1+hβ2, mSlo1+2K2A, mSlo1+3K3A, mSlo1+4K4A, mSlo1+4K4D and mSlo1+4K4R as indicated. They are 1.22±0.04 (n = 8) and 1.81±0.06 (n = 17), 1.43±0.04 (n = 15), 1.28±0.02 (n = 12), 1.24±0.03 (n = 13), 1.17±0.01 (n = 13) and 1.55±0.03 (n = 12) for mSlo1, mSlo1+hβ2, mSlo1+2K2A, mSlo1+3K3A, mSlo1+4K4A, mSlo1+4K4D and mSlo1+4K4R, respectively.</p

Lysine-Rich Extracellular Rings Formed by hβ2 Subunits Confer the Outward Rectification of BK Channels-2

, the 2K2A, 3K3A, 4K4A and 4K4D are short for K137AK141A, K137AK141AK147A, K137AK141AK147AK150A and K137DK141DK147DK150D, respectively. The voltage protocol is the same as shown in . Scale bars represent 10 ms and 5 nA, respectively. B. The instantaneous tail currents from the top to the bottom are for mSlo1+2K2A, mSlo1+3K3A, mSlo1+4K4A, mSlo1+4K4D and mSlo1+4K4R, respectively. The voltage protocol is the same as described in . Scale bars represent 10 ms and 5 nA, respectively. C. The instantaneous I-V curves normalized to the tail currents at +100 mV are for mSlo1+2K2A, mSlo1+3K3A, mSlo1+4K4A, mSlo1+4K4D and mSlo1+4K4R as indicated. The long dash and the dotted line are for mSlo1+hβ2 and mSlo1, respectively. D. The rectification ratios R