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1.
Nanoscale ; 10(5): 2555-2567, 2018 Feb 01.
Article in English | MEDLINE | ID: mdl-29349454

ABSTRACT

We report on the adsorption dynamics of phospholipid membranes on graphene-coated substrates using the quartz crystal microbalance with dissipation monitoring (QCM-D) technique. We compare the lipid vesicle interaction and membrane formation on gold and silicon dioxide QCM crystal surfaces with their graphene oxide (GO) and reduced (r)GO coated counterparts, and report on the different lipid structures obtained. We establish graphene derivative coatings as support surfaces with tuneable hydrophobicity for the formation of controllable lipid structures. One structure of interest formed is lipid monolayer membranes which were formed on rGO, which are otherwise challenging to produce. We also demonstrate and monitor biotin-avidin binding on such a membrane, which will then serve as a platform for a wide range of biosensing applications. The QCM-D technique could be extended to both fundamental studies and applications of other covalent and non-covalent interactions in 2-dimensional materials.

2.
Am J Psychiatry ; 158(12): 2043-7, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11729023

ABSTRACT

OBJECTIVE: Insomnia and nightmares are perceived as secondary phenomena in posttraumatic stress disorder (PTSD). Scant treatment research has targeted these two sleep disturbances. This study reports on an open-label trial of cognitive behavior therapy for insomnia and disturbing dreams in crime victims with PTSD. The relationship among nightmares, sleep disturbances, and PTSD symptoms is discussed. METHOD: Sixty-two participants completed a 10-hour group treatment consisting of imagery rehearsal for nightmares and sleep hygiene, stimulus control, and sleep restriction for insomnia. Nightmare frequency, sleep quality, sleep impairment, and ratings for PTSD, anxiety, and depression symptoms were assessed at baseline and at the 3-month follow-up. RESULTS: All measures demonstrated improvement that was roughly equivalent to changes in clinical severity from severe to moderate for sleep quality, sleep impairment, and nightmare frequency, from borderline severe to borderline moderate for PTSD symptoms, and from extremely severe to borderline severe for anxiety and depression symptoms. CONCLUSIONS: In this uncontrolled study, successful treatment for insomnia and nightmares in crime victims was associated with improvement in symptoms of PTSD, anxiety, and depression. Participants with clinical improvements in PTSD symptoms demonstrated significantly greater improvement in sleep quality and nightmare frequency than those whose PTSD symptoms did not improve.


Subject(s)
Cognitive Behavioral Therapy , Crime Victims , Dreams , Evidence-Based Medicine , Sleep Initiation and Maintenance Disorders/therapy , Stress Disorders, Post-Traumatic/therapy , Adult , Female , Follow-Up Studies , Humans , Imagery, Psychotherapy , Male , Middle Aged , Psychotherapy, Group , Sleep Initiation and Maintenance Disorders/psychology , Stress Disorders, Post-Traumatic/psychology
3.
Chest ; 120(6): 1923-9, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11742923

ABSTRACT

OBJECTIVE: To assess the prevalence of insomnia symptoms in patients with objectively diagnosed sleep-disordered breathing (SDB). DESIGN: Retrospective medical chart review of a representative sample of patients with SDB. SETTING: University sleep-disorders clinic and laboratory. PATIENTS: Two hundred thirty-one patients with SDB were selected from a pool of approximately 2,000 patients with sleep disorders. MEASUREMENTS: Data were extracted from intake questionnaires and polysomnographic studies. RESULTS: Of 231 patients with SDB diagnoses, 115 patients reported no insomnia complaints (SDB-only patients) and 116 patients reported clinically meaningful insomnia complaints (SDB-plus patients). Compared to SDB-only patients, SDB-plus patients reported significantly worse mean sleep characteristics consistent with insomnia, including sleep latency (17 min vs 65 min), total sleep time (7.2 h vs 5.6 h), and sleep efficiency (92% vs 75%). SDB-plus patients experienced significantly more psychiatric disorders, cognitive-emotional symptoms, and physical and mental symptoms that disrupted or prevented sleep. SDB-plus patients also reported greater use of sedative and psychotropic medications and had significantly more primary complaints of insomnia, restless legs or leg jerks, and poor sleep quality despite having relatively similar referral rates for sleep apnea or complaints of loud snoring. CONCLUSIONS: Problematic insomnia symptoms were reported by 50% of a representative sample of patients with objectively diagnosed SDB. Research is needed to determine the degree to which insomnia and related symptoms and behaviors interfere with SDB treatment.


Subject(s)
Sleep Apnea, Obstructive/diagnosis , Sleep Initiation and Maintenance Disorders/etiology , Adult , Aged , Comorbidity , Cross-Sectional Studies , Diagnosis, Differential , Female , Humans , Male , Mental Disorders/diagnosis , Mental Disorders/epidemiology , Middle Aged , New Mexico/epidemiology , Retrospective Studies , Sleep Apnea, Obstructive/epidemiology , Sleep Initiation and Maintenance Disorders/epidemiology
4.
JAMA ; 286(5): 537-45, 2001 Aug 01.
Article in English | MEDLINE | ID: mdl-11476655

ABSTRACT

CONTEXT: Chronic nightmares occur frequently in patients with posttraumatic stress disorder (PTSD) but are not usually a primary target of treatment. OBJECTIVE: To determine if treating chronic nightmares with imagery rehearsal therapy (IRT) reduces the frequency of disturbing dreams, improves sleep quality, and decreases PTSD symptom severity. DESIGN, SETTING, AND PARTICIPANTS: Randomized controlled trial conducted from 1995 to 1999 among 168 women in New Mexico; 95% had moderate-to-severe PTSD, 97% had experienced rape or other sexual assault, 77% reported life-threatening sexual assault, and 58% reported repeated exposure to sexual abuse in childhood or adolescence. INTERVENTION: Participants were randomized to receive treatment (n = 88) or to the wait-list control group (n = 80). The treatment group received IRT in 3 sessions; controls received no additional intervention, but continued any ongoing treatment. MAIN OUTCOME MEASURES: Scores on the Nightmare Frequency Questionnaire (NFQ), Pittsburgh Sleep Quality Index (PSQI), PTSD Symptom Scale (PSS), and Clinician-Administered PTSD Scale (CAPS) at 3- and 6-month follow-up. RESULTS: A total of 114 participants completed follow-up at 3 and/or 6 months. Comparing baseline to follow-up (n = 97-114), treatment significantly reduced nights per week with nightmares (Cohen d = 1.24; P<.001) and number of nightmares per week (Cohen d = 0.85; P<.001) on the NFQ and improved sleep (on the PSQI, Cohen d = 0.67; P<.001) and PTSD symptoms (on the PSS, Cohen d = 1.00; P<.001 and on the CAPS, Cohen d = 1.53; P<.001). Control participants showed small, nonsignificant improvements for the same measures (mean Cohen d = 0.21). In a 3-point analysis (n = 66-77), improvements occurred in the treatment group at 3-month follow-up (treatment vs control group, Cohen d = 1.15 vs 0.07 for nights per week with nightmares; 0.95 vs -0.06 for nightmares per week; 0.77 vs 0.31 on the PSQI, and 1.06 vs 0.31 on the PSS) and were sustained without further intervention or contact between 3 and 6 months. An intent-to-treat analysis (n = 168) confirmed significant differences between treatment and control groups for nightmares, sleep, and PTSD (all P<.02) with moderate effect sizes for treatment (mean Cohen d = 0.60) and small effect sizes for controls (mean Cohen d = 0.14). Posttraumatic stress symptoms decreased by at least 1 level of clinical severity in 65% of the treatment group compared with symptoms worsening or not changing in 69% of controls (chi(2)(1) = 12.80; P<.001). CONCLUSIONS: Imagery rehearsal therapy is a brief, well-tolerated treatment that appears to decrease chronic nightmares, improve sleep quality, and decrease PTSD symptom severity.


Subject(s)
Dreams , Imagery, Psychotherapy , Sex Offenses/psychology , Sleep Wake Disorders/etiology , Sleep Wake Disorders/therapy , Stress Disorders, Post-Traumatic/complications , Stress Disorders, Post-Traumatic/therapy , Adult , Aged , Chronic Disease , Cognitive Behavioral Therapy , Female , Humans , Middle Aged , Prospective Studies , Sickness Impact Profile , Survivors/psychology
5.
Biol Psychiatry ; 49(11): 948-53, 2001 Jun 01.
Article in English | MEDLINE | ID: mdl-11377413

ABSTRACT

BACKGROUND: Sleep disturbance in posttraumatic stress disorder is very common. However, no previous posttraumatic stress disorder studies systematically examined sleep breathing disturbances, which might influence nightmares, insomnia, and posttraumatic stress disorder symptoms. METHODS: Forty-four consecutive crime victims with nightmares and insomnia underwent standard polysomnography coupled with a nasal pressure transducer to measure airflow limitation diagnostic of obstructive sleep apnea and upper airway resistance syndrome. RESULTS: Forty of 44 participants tested positive on objective sleep studies based on conservative respiratory disturbance indices of more than 15 events per hour; 22 patients suffered from obstructive sleep apnea and 18 suffered from upper airway resistance syndrome. CONCLUSIONS: In an uncontrolled study, insomnia and sleep-disordered breathing were extremely prevalent in this small and select sample of crime victims. Research is needed to study 1) prevalence of sleep-disordered breathing in other posttraumatic stress disorder populations using appropriate controls and nasal pressure transducers and 2) effects of sleep treatment on posttraumatic stress symptoms in trauma survivors with comorbid obstructive sleep apnea or upper airway resistance syndrome. In the interim, some posttraumatic stress disorder patients may benefit from sleep medicine evaluations.


Subject(s)
Crime Victims/psychology , Dreams , Sleep Apnea Syndromes/complications , Sleep Initiation and Maintenance Disorders/complications , Sleep Initiation and Maintenance Disorders/psychology , Stress Disorders, Post-Traumatic/etiology , Adult , Female , Humans , Male , Psychometrics , Sleep Initiation and Maintenance Disorders/diagnosis , Sleep, REM/physiology , Stress Disorders, Post-Traumatic/diagnosis , Surveys and Questionnaires
6.
J Trauma Stress ; 14(4): 647-65, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11776415

ABSTRACT

Sleep quality and posttraumatic stress disorder (PTSD) were examined in 151 sexual assault survivors, 77% of whom had previously reported symptoms of sleep-disordered breathing (SDB) or sleep movement disorders (SMD) or both. Participants completed the Pittsburgh Sleep Quality Index (PSQI) and the Posttraumatic Stress Scale (PSS). High PSQI scores reflected extremely poor sleep quality and correlated with PSS scores. PSQI scores were greater in participants with potential SDB or SMD or both. PSQI or PSS scores coupled with body-mass index and use of antidepressants or anxiolytics predicted potential sleep disorders. The relationship between sleep and posttraumatic stress appears to be more complex than can be explained by the current PTSD paradigm; and, sleep breathing and sleep movement disorders may be associated with this complexity.


Subject(s)
Nocturnal Myoclonus Syndrome/etiology , Rape/psychology , Sleep Apnea Syndromes/etiology , Sleep Wake Disorders/etiology , Stress Disorders, Post-Traumatic/psychology , Survivors/psychology , Adult , Female , Humans , Nocturnal Myoclonus Syndrome/diagnosis , Nocturnal Myoclonus Syndrome/epidemiology , Severity of Illness Index , Sleep Apnea Syndromes/diagnosis , Sleep Apnea Syndromes/epidemiology , Sleep Wake Disorders/diagnosis , Sleep Wake Disorders/epidemiology , Stress Disorders, Post-Traumatic/diagnosis , Surveys and Questionnaires
7.
J Psychosom Res ; 49(5): 291-8, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11164053

ABSTRACT

OBJECTIVE: To assess the impact of treatment for co-morbid sleep-disordered breathing (SDB) on patients with nightmares and post-traumatic stress. METHODS: Twenty-three chronic nightmare sufferers (15 with post-traumatic stress disorder, PTSD) who also suffered co-morbid SDB (obstructive sleep apnea, OSA, n=16; upper airway resistance syndrome, UARS, n=7) completed a telephone interview, on average, 21 months after having been offered treatment for SDB at a university sleep disorders clinic. RESULTS: At follow-up, 14 reported maintaining treatment (Treatment Group) and 9 reported discontinuing treatment (No-Treatment Group). More patients in the Treatment Group reported improvement in sleep (93% vs. 33%) and in daytime well being (93% vs. 33%) compared with those in the No-Treatment group. The Treatment Group reported a median improvement in nightmares of 85% compared with a median 10% worsening in the No-Treatment Group. In the PTSD subset (n=15), nine in the Treatment Group reported a median 75% improvement in PTSD symptoms whereas six in the No-Treatment Group reported a median 43% worsening. CONCLUSION: In this small sample of patients, treatment of SDB was associated with improvements in nightmares and PTSD. Relationships between nightmares, PTSD and SDB are discussed.


Subject(s)
Dreams/psychology , Positive-Pressure Respiration/methods , Sleep Apnea Syndromes/therapy , Stress Disorders, Post-Traumatic/psychology , Adult , Body Mass Index , Chronic Disease , Comorbidity , Female , Follow-Up Studies , Humans , Male , Periodicity , Polysomnography , Sleep Apnea Syndromes/epidemiology , Stress Disorders, Post-Traumatic/diagnosis , Stress Disorders, Post-Traumatic/epidemiology , Surveys and Questionnaires
8.
Crisis ; 21(4): 163-170, 2000.
Article in English | MEDLINE | ID: mdl-11419527

ABSTRACT

The role of sleep in psychiatric illness in general, and depression and suicidality in particular, is poorly understood and has not been well researched despite the pervasiveness of sleep complaints in these conditions. As an exploratory, hypothesis-generating study, female sexual assault survivors with posttraumatic stress disorder (n = 153) who had enrolled in a nightmare-treatment program were assessed for subjectively determined sleep breathing and sleep movement disorders. Diagnoses of potential disorders were based on clinical practice parameters and research algorithms from thefield of sleep disorders medicine. Potential sleep breathing and sleep movement disorders were present in 80% of the participants (n = 123) and included three subgroups: sleep-disordered breathing only (n = 23); sleep movement disorder only (n = 45); and both sleep disorders (n = 55). Based on the Hamilton Depression Rating Scale and Suicide subscale, participants with potential sleep disorders suffered greater depression (Cohen's d = .73-.96; p < .01) and greater suicidality (Cohen's d = .57-.78; p < .05) in comparison to participants without potential sleep disorders. The group with both sleep disorders suffered from the most severe depression and suicidality. A provisional hypothesis is formulated that describes how sleep disorders may exacerbate depression and suicidality through the effects of chronic sleep fragmentation.


Subject(s)
Depression/epidemiology , Sex Offenses/psychology , Sleep Wake Disorders/epidemiology , Suicide/psychology , Survivors/psychology , Depression/etiology , Female , Humans , New Mexico/epidemiology , Psychiatric Status Rating Scales , Severity of Illness Index , Sleep Wake Disorders/etiology , Stress Disorders, Post-Traumatic/epidemiology , Survivors/statistics & numerical data
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