ROLE OF M-CHANNELS IN SEIZURE GENERATION: A STUDY IN ZEBRAFISH

Epilepsy is a neurological disorder that is characterized by recurrent seizures that result from an overall increase in neuronal excitability. A subset of epilepsies are caused by gene mutations majority of which result in ion channel dysfunction, alteration of neurotransmitter receptors or cause brain deformities. For this thesis, we examined a particular subset of potassium channels (M-channels) in which mutations of the corresponding KCNQ genes results in a seizure disorder known as benign familial neonatal convulsions (BFNC).M-channels produce an inhibitory potassium current that allows firing of single action potentials but opposes sustained depolarization and repetitive firing of action potentials. Suppression of this channel thus results in continuous firing of action potentials and may cause general network hyperexcitation. We sought to study the role of these M-channels in seizure generation using zebrafish larvae as the model organism. First we determined which of the M-channel genes KCNQ2, KCNQ3 and KCNQ5 were expressed in Zebrafish. We were able to confirm the expression of KCNQ3 and KCNQ5 but not KCNQ2 due to sequence assembly errors. We then determined the developmental expression and localization of both KCNQ3 and KCNQ5 in the zebrafish larvae. At the channel level, we examined the effect of pharmacological alteration of M-channel function in vivo. We were able to show in that blocking M-channels using linopirdine was sufficient to cause seizure-like electrical bursting in the brain, as well as stereotyped seizure behaviors. These seizure phenotypes could be blocked and also reversed by application of the M-channel enhancer Retigabine. We then knocked down the expression of KCNQ3 using targeted morpholinos, and were able to confirm that knock-down of KCNQ3 in zebrafish larvae was sufficient to produce an electrical seizure phenotype in the brain. Overall, we confirmed the specific hypothesis that suppression of M-channel activity in vivo alters neuronal function in a manner that leads to hyperexcitability and seizures. Since the zebrafish expressed specific M-channel genes and disruption of either gene function or channel function (pharmacologically) consistently produced a seizure phenotype, we were able to show that the zebrafish is a viable model system in which to study M-channels and BFNC

Violence Against Women in Selected Areas of the United States.

Objectives. We determined the prevalence of recent emotional, physical, and sexual violence against women and their associations with HIV-related risk factors in women living in the United States

Safety and Tolerability of Maraviroc-Containing Regimens to Prevent HIV Infection in Women: A Phase 2 Randomized Trial

BACKGROUND—Maraviroc (MVC) is a candidate drug for HIV PrEP. OBJECTIVE—To assess the safety/tolerability of MVC-containing PrEP in U.S. women at-risk for HIV over 48 weeks. DESIGN—Phase 2 randomized, controlled, double-blinded study of four PrEP regimens (#NCT01505114). SETTING—Twelve clinical research sites of the HIV Prevention Trials Network and AIDS Clinical Trials Group. PARTICIPANTS—HIV-uninfected women reporting condomless vaginal or anal intercourse with ≥1 HIV-infected or unknown-serostatus man within 90 days. INTERVENTIONS—MVC alone, MVC+emtricitabine (FTC), MVC+tenofovir disoproxil fumarate (TDF), and TDF+FTC (control). MEASUREMENTS—At each visit, clinical and laboratory (including HIV) assessments were conducted. Primary outcomes were grade 3–4 adverse events and time to permanent regimen discontinuation. Analyses were conducted on all randomized participants, according to original regimen assignment. RESULTS—Among 188 participants, 85% completed follow-up, 11% withdrew early, and 4% were lost-to-follow-up; 19% discontinued their regimen prematurely. Number discontinuing and time-to-discontinuation did not differ among regimens. Grade 3/4 adverse events occurred in 5 (MVC), 13 (MVC+FTC), 9 (MVC+TDF) and 8 (TDF+FTC) participants; rates did not differ among regimens. One death occurred (suicide; MVC+FTC), judged not regimen-related. Of available samples at week 48 (n=126), 60% demonstrated detectable drug concentrations. No new HIV infections occurred. LIMITATIONS—Participants were not necessarily high-risk for HIV. Regimen was 3 pills daily. Study was not powered for efficacy. CONCLUSIONS—MVC-containing PrEP regimens were safe and well-tolerated compared to the control regimen of TDF+FTC in U.S. women. No new HIV infections occurred, although whether this was due to low risk of the population or to protection from the study regimens is not certain. MVC-containing PrEP for women may warrant further study. FUNDING SOURCE—U.S. National Institutes of Healt

Safety and Tolerability of Maraviroc-Containing Regimens to Prevent HIV Infection in Women: A Phase 2 Randomized Trial.

BACKGROUND—Maraviroc (MVC) is a candidate drug for HIV PrEP. OBJECTIVE—To assess the safety/tolerability of MVC-containing PrEP in U.S. women at-risk for HIV over 48 weeks. DESIGN—Phase 2 randomized, controlled, double-blinded study of four PrEP regimens (#NCT01505114). SETTING—Twelve clinical research sites of the HIV Prevention Trials Network and AIDS Clinical Trials Group. PARTICIPANTS—HIV-uninfected women reporting condomless vaginal or anal intercourse with ≥1 HIV-infected or unknown-serostatus man within 90 days. INTERVENTIONS—MVC alone, MVC+emtricitabine (FTC), MVC+tenofovir disoproxil fumarate (TDF), and TDF+FTC (control). MEASUREMENTS—At each visit, clinical and laboratory (including HIV) assessments were conducted. Primary outcomes were grade 3–4 adverse events and time to permanent regimen discontinuation. Analyses were conducted on all randomized participants, according to original regimen assignment. RESULTS—Among 188 participants, 85% completed follow-up, 11% withdrew early, and 4% were lost-to-follow-up; 19% discontinued their regimen prematurely. Number discontinuing and time-to-discontinuation did not differ among regimens. Grade 3/4 adverse events occurred in 5 (MVC), 13 (MVC+FTC), 9 (MVC+TDF) and 8 (TDF+FTC) participants; rates did not differ among regimens. One death occurred (suicide; MVC+FTC), judged not regimen-related. Of available samples at week 48 (n=126), 60% demonstrated detectable drug concentrations. No new HIV infections occurred. LIMITATIONS—Participants were not necessarily high-risk for HIV. Regimen was 3 pills daily. Study was not powered for efficacy. CONCLUSIONS—MVC-containing PrEP regimens were safe and well-tolerated compared to the control regimen of TDF+FTC in U.S. women. No new HIV infections occurred, although whether this was due to low risk of the population or to protection from the study regimens is not certain. MVC-containing PrEP for women may warrant further study. FUNDING SOURCE—U.S. National Institutes of Healt