15 research outputs found
Can Medication Free, Treatment-Resistant, Depressed Patients Who Initially Respond to TMS Be Maintained Off Medications? A Prospective, 12-Month Multisite Randomized Pilot Study
AbstractBackgroundRepetitive transcranial magnetic stimulation (TMS) is efficacious for acute treatment of resistant major depressive disorder (MDD), but there is little information on maintenance TMS after acute response.Objective/hypothesisThis pilot feasibility study investigated 12-month outcomes comparing two maintenance TMS approaches – a scheduled, single TMS session delivered monthly (SCH) vs. observation only (OBS).MethodsAntidepressant-free patients with unipolar, non-psychotic, treatment-resistant MDD participated in a randomized, open-label, multisite trial. Patients meeting protocol-defined criteria for improvement after six weeks of acute TMS were randomized to SCH or OBS regimens. TMS reintroduction was available for symptomatic worsening; all patients remained antidepressant-free during the trial.ResultsSixty-seven patients enrolled in the acute phase, and 49 (73%) met randomization criteria. Groups were matched, although more patients in the SCH group had failed ≥2 antidepressants (p = .035). There were no significant group differences on any outcome measure. SCH patients had nonsignificantly longer time to first TMS reintroduction, 91 ± 66 days, vs. OBS, 77 ± 52 days; OBS patients were nonsignificantly more likely to need reintroduction (odds ratio = 1.21, 95% CI .38–3.89). Reintroduction lasted 14.3 ± 17.8 days (SCH) and 16.9 ± 18.9 days (OBS); 14/18 (78%) SCH and 17/27 (63%) OBS responded to reintroduction. Sixteen patients (32.7%) completed all 53 weeks of the study.ConclusionsMaintaining treatment-resistant depressed patients off medications with periodic TMS appears feasible in some cases. There was no statistical advantage of SCH vs. OBS, although SCH was associated with a nonsignificantly longer time to relapse. Those who initially respond to TMS have a strong chance of re-responding if relapse occurs
The Importance of pH in Regulating the Function of the Fasciola hepatica Cathepsin L1 Cysteine Protease
The helminth parasite Fasciola hepatica secretes cathepsin L cysteine proteases to invade its host, migrate through tissues and digest haemoglobin, its main source of amino acids. Here we investigated the importance of pH in regulating the activity and functions of the major cathepsin L protease FheCL1. The slightly acidic pH of the parasite gut facilitates the auto-catalytic activation of FheCL1 from its inactive proFheCL1 zymogen; this process was ∼40-fold faster at pH 4.5 than at pH 7.0. Active mature FheCL1 is very stable at acidic and neutral conditions (the enzyme retained ∼45% activity when incubated at 37°C and pH 4.5 for 10 days) and displayed a broad pH range for activity peptide substrates and the protein ovalbumin, peaking between pH 5.5 and pH 7.0. This pH profile likely reflects the need for FheCL1 to function both in the parasite gut and in the host tissues. FheCL1, however, could not cleave its natural substrate Hb in the pH range pH 5.5 and pH 7.0; digestion occurred only at pH≤4.5, which coincided with pH-induced dissociation of the Hb tetramer. Our studies indicate that the acidic pH of the parasite relaxes the Hb structure, making it susceptible to proteolysis by FheCL1. This process is enhanced by glutathione (GSH), the main reducing agent contained in red blood cells. Using mass spectrometry, we show that FheCL1 can degrade Hb to small peptides, predominantly of 4–14 residues, but cannot release free amino acids. Therefore, we suggest that Hb degradation is not completed in the gut lumen but that the resulting peptides are absorbed by the gut epithelial cells for further processing by intracellular di- and amino-peptidases to free amino acids that are distributed through the parasite tissue for protein anabolism
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Double-blind randomized controlled study of the efficacy, safety and tolerability of eszopiclone vs placebo for the treatment of patients with post-traumatic stress disorder and insomnia.
BackgroundSleep disturbance is a core feature of post-traumatic stress disorder (PTSD). Given the relationship between sleep disturbance and PTSD, there has been a relative paucity of studies examining the potential therapeutic impact of using pharmacotherapy to target sleep disturbance in patients with PTSD. Eszopiclone (ESZ) is a non-benzodiazepine y-aminobutyric acid-A receptor agonist indicated for the treatment of sleep and may affect sleep in patients with PTSD.AimTo evaluate the efficacy of ESZ vs placebo (PBO) for patients with PTSD and insomnia.MethodsThe study was a 12-wk, double blind, randomized controlled trial with 3 mg of ESZ (n = 13) or PBO (n = 12).ResultsPatients in both arms experienced significant improvement in PTSD symptoms as assessed by the Clinician-Administered PTSD Scale for DSM-IV (CAPS): ESZ (t11 = -3.12, P = 0.005) and PBO (t11 = -3.5, P = 0.002) and by self-report with the Short PTSD Rating Interview (ESZ t11 = -3.38, P = 0.003 and PBO t11 = -4.48, P = 0.0005). There were no significant differences between treatments on the CAPS (t22 = -0.13, P = 0.70) or the Short PTSD Rating Interview (t22 = -0.58, P = 0.56). Similarly, both treated groups improved on sleep measures as assessed by the Pittsburgh Sleep Quality Index with PTSD Addendum (PSQI) and on total sleep time (TST) and sleep latency assessed by actigraphy with no significant differences between groups (PSQI t22 = -0.24, P = 0.81; total sleep time t10 = 0.13, P = 0.90 and sleep latency t10 = 0.68, P = 0.50). There was a significant correlation between improvement in sleep and overall improvement in PTSD as measured by change scores on the PSQI and CAPS, r(8) = 0.79, P = 0.01 for ESZ treated subjects, but not for those treated with PBO r(9) = 0.16, P = 0.69. Adverse events of ESZ were consistent with the known profile of the medication including dysgeusia (30%, mild), sedation (20%, mild) and headache (20%, moderate to severe).ConclusionResults do not support the hypothesis of a specific positive effect of ESZ compared to PBO for measures of PTSD and associated sleep disturbance
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Double-blind randomized controlled study of the efficacy, safety and tolerability of eszopiclone vs placebo for the treatment of patients with post-traumatic stress disorder and insomnia.
BackgroundSleep disturbance is a core feature of post-traumatic stress disorder (PTSD). Given the relationship between sleep disturbance and PTSD, there has been a relative paucity of studies examining the potential therapeutic impact of using pharmacotherapy to target sleep disturbance in patients with PTSD. Eszopiclone (ESZ) is a non-benzodiazepine y-aminobutyric acid-A receptor agonist indicated for the treatment of sleep and may affect sleep in patients with PTSD.AimTo evaluate the efficacy of ESZ vs placebo (PBO) for patients with PTSD and insomnia.MethodsThe study was a 12-wk, double blind, randomized controlled trial with 3 mg of ESZ (n = 13) or PBO (n = 12).ResultsPatients in both arms experienced significant improvement in PTSD symptoms as assessed by the Clinician-Administered PTSD Scale for DSM-IV (CAPS): ESZ (t11 = -3.12, P = 0.005) and PBO (t11 = -3.5, P = 0.002) and by self-report with the Short PTSD Rating Interview (ESZ t11 = -3.38, P = 0.003 and PBO t11 = -4.48, P = 0.0005). There were no significant differences between treatments on the CAPS (t22 = -0.13, P = 0.70) or the Short PTSD Rating Interview (t22 = -0.58, P = 0.56). Similarly, both treated groups improved on sleep measures as assessed by the Pittsburgh Sleep Quality Index with PTSD Addendum (PSQI) and on total sleep time (TST) and sleep latency assessed by actigraphy with no significant differences between groups (PSQI t22 = -0.24, P = 0.81; total sleep time t10 = 0.13, P = 0.90 and sleep latency t10 = 0.68, P = 0.50). There was a significant correlation between improvement in sleep and overall improvement in PTSD as measured by change scores on the PSQI and CAPS, r(8) = 0.79, P = 0.01 for ESZ treated subjects, but not for those treated with PBO r(9) = 0.16, P = 0.69. Adverse events of ESZ were consistent with the known profile of the medication including dysgeusia (30%, mild), sedation (20%, mild) and headache (20%, moderate to severe).ConclusionResults do not support the hypothesis of a specific positive effect of ESZ compared to PBO for measures of PTSD and associated sleep disturbance
Sleep quality predicts treatment outcome in CBT for social anxiety disorder.
BackgroundSleep quality may be an important, yet relatively neglected, predictor of treatment outcome in cognitive-behavioral therapy (CBT) for anxiety disorders. Specifically, poor sleep quality may impair memory consolidation of in-session extinction learning. We therefore examined sleep quality as a predictor of treatment outcome in CBT for social anxiety disorder and the impact of d-cycloserine (DCS) on this relationship.MethodsOne hundred sixty-nine participants with a primary diagnosis of DSM-IV generalized social anxiety disorder were recruited across three sites. Participants were enrolled in 12 weeks of group CBT. Participants randomly received 50 mg of DCS (n = 87) or pill placebo (n = 82) 1 hr prior to sessions 3-7. Participants completed a baseline measure of self-reported sleep quality and daily diaries recording subjective feelings of being rested upon wakening. Outcome measures including social anxiety symptoms and global severity scores were assessed at each session.ResultsPoorer baseline sleep quality was associated with slower improvement and higher posttreatment social anxiety symptom and severity scores. Moreover, patients who felt more "rested" after sleeping the night following a treatment session had lower levels of symptoms and global severity at the next session, controlling for their symptoms and severity scores the previous session. Neither of these effects were moderated by DCS condition.ConclusionsOur findings suggest that poor sleep quality diminishes the effects of CBT for social anxiety disorder and this relation is not attenuated by DCS administration. Therapeutic attention to sleep quality prior to initiation of CBT and during the acute treatment phase may be clinically indicated
Sleep quality and outcome of exposure therapy in adults with social anxiety disorder
Introduction: Poor sleep is prevalent among individuals with social anxiety disorder (SAD) and may negatively affect exposure therapy outcomes. Poor sleep may impair memory and learning, and thus compromise fear extinction learning thought to take place in exposure therapy. We examined poor sleep as a predictor of exposure therapy outcomes for SAD and the moderating role of d-cycloserine (DCS) on this relationship. Methods: Participants were 152 individuals with a primary diagnosis of SAD. As part of a randomized clinical trial evaluating the efficacy of DCS for enhancing the effects of exposure therapy, they completed self-report baseline measure of sleep quality, and self-report sleep diaries assessing sleep duration (total sleep time [TST]) and sleep quality the nights before and after treatment sessions. Results: Poorer baseline sleep quality was significantly associated with slower improvement over time and worse symptom outcomes at the end of treatment and follow-up after controlling for baseline symptoms of depression and social anxiety. Greater TST the night before treatment predicted lower SAD symptoms at the next session, after controlling for symptoms at the previous session. There was no relation between prior or subsequent night sleep quality on symptoms at the next session. No associations were moderated by DCS. Conclusions: We replicated and extended findings indicating that poor sleep quality is associated with poorer exposure therapy outcomes for SAD. Assessing for sleep difficulties before treatment initiation and incorporating sleep interventions into treatment may enhance exposure therapy outcomes for SAD.12 month embargo; first published: 19 May 2021This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
<i>Fasciola hepatica</i> cathepsin L-like proteases: biology, function and potential in the development of first generation liver fluke vaccines.
Fasciola hepatica secretes cathepsin L proteases that facilitate the penetration of the parasite through the tissues of its host, and also participate in functions such as feeding and immune evasion. The major proteases, cathepsin L1 (FheCL1) and cathepsin L2 (FheCL2) are members of a lineage that gave rise to the human cathepsin Ls, Ks and Ss, but while they exhibit similarities in their substrate specificities to these enzymes they differ in having a wider pH range for activity and an enhanced stability at neutral pH. There are presently 13 Fasciola cathepsin L cDNAs deposited in the public databases representing a gene family of at least seven distinct members, although the temporal and spatial expression of each of these members in the developmental stage of F. hepatica remains unclear. Immunolocalisation and in situ hybridisation studies, using antibody and DNA probes, respectively, show that the vast majority of cathepsin L gene expression is carried out in the epithelial cells lining the parasite gut. Within these cells the enzyme is packaged into secretory vesicles that release their contents into the gut lumen for the purpose of degrading ingested host tissue and blood. Liver flukes also express a novel multi-domain cystatin that may be involved in the regulation of cathepsin L activity. Vaccine trials in both sheep and cattle with purified native FheCL1 and FheCL2 have shown that these enzymes can induce protection, ranging from 33 to 79%, to experimental challenge with metacercariae of F. hepatica, and very potent anti-embryonation/hatch rate effects that would block parasite transmission. In this article we review the vaccine trials carried out over the past 8 years, the role of antibody and T cell responses in mediating protection and discuss the prospects of the cathepsin Ls in the development of first generation recombinant liver fluke vaccines. © 2003 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved
Structural and Functional Relationships in the Virulence-associated Cathepsin L Proteases of the Parasitic Liver Fluke, Fasciola hepatica
The helminth parasite Fasciola hepatica secretes cysteine proteases to facilitate tissue invasion, migration, and development within the mammalian host. The major proteases cathepsin L1 (FheCL1) and cathepsin L2 (FheCL2) were recombinantly produced and biochemically characterized. By using site-directed mutagenesis, we show that residues at position 67 and 205, which lie within the S2 pocket of the active site, are critical in determining the substrate and inhibitor specificity. FheCL1 exhibits a broader specificity and a higher substrate turnover rate compared with FheCL2. However, FheCL2 can efficiently cleave substrates with a Pro in the P2 position and degrade collagen within the triple helices at physiological pH, an activity that among cysteine proteases has only been reported for human cathepsin K. The 1.4-Å three-dimensional structure of the FheCL1 was determined by x-ray crystallography, and the three-dimensional structure of FheCL2 was constructed via homology-based modeling. Analysis and comparison of these structures and our biochemical data with those of human cathepsins L and K provided an interpretation of the substrate-recognition mechanisms of these major parasite proteases. Furthermore, our studies suggest that a configuration involving residue 67 and the “gatekeeper” residues 157 and 158 situated at the entrance of the active site pocket create a topology that endows FheCL2 with its unusual collagenolytic activity. The emergence of a specialized collagenolytic function in Fasciola likely contributes to the success of this tissue-invasive parasite