Quantum Control of Photoelectron Circular Dichroism.

We demonstrate coherent control over the photoelectron circular dichroism in randomly oriented chiral molecules, based on quantum interference between multiple photoionization pathways. To significantly enhance the chiral signature, we use a finite manifold of indistinguishable (1+1^{'}) resonantly enhanced multiphoton ionization pathways interfering at a common photoelectron energy but probing different intermediate states. We show that this coherent control mechanism maximizes the number of molecular states that constructively contribute to the dichroism at an optimal photoelectron energy and thus outperforms other schemes, including interference between opposite-parity pathways driven by bichromatic (ω, 2ω) fields as well as sequential pump-probe ionization.

Perfect control of photoelectron anisotropy for randomly oriented ensembles of molecules by XUV REMPI and polarization shaping.

We report two schemes to generate perfect anisotropy in the photoelectron angular distribution of a randomly oriented ensemble of polyatomic molecules. In order to exert full control over the anisotropy of photoelectron emission, we exploit interferences between single-photon pathways and a manifold of resonantly enhanced two-photon pathways. These are shown to outperform nonsequential (ω, 2ω) bichromatic phase control for the example of CHFClBr molecules. We are able to optimize pulses that yield anisotropic photoelectron emission thanks to a very efficient calculation of photoelectron momentum distributions. This is accomplished by combining elements of quantum chemistry, variational scattering theory, and time-dependent perturbation theory.

Theoretical description of circular dichroism in photoelectron angular distributions of randomly oriented chiral molecules after multi-photon photoionization.

Photoelectron circular dichroism refers to the forward/backward asymmetry in the photoelectron angular distribution with respect to the propagation axis of circularly polarized light. It has recently been demonstrated in femtosecond multi-photon photoionization experiments with randomly oriented camphor and fenchone molecules [C. Lux et al., Angew. Chem., Int. Ed. 51, 4755 (2012) and C. S. Lehmann et al., J. Chem. Phys. 139, 234307 (2013)]. A theoretical framework describing this process as (2+1) resonantly enhanced multi-photon ionization is constructed, which consists of two-photon photoselection from randomly oriented molecules and successive one-photon ionization of the photoselected molecules. It combines perturbation theory for the light-matter interaction with ab initio calculations for the two-photon absorption and a single-center expansion of the photoelectron wavefunction in terms of hydrogenic continuum functions. It is verified that the model correctly reproduces the basic symmetry behavior expected under exchange of handedness and light helicity. When applied to fenchone and camphor, semi-quantitative agreement with the experimental data is found, for which a sufficient d wave character of the electronically excited intermediate state is crucial.

Prevalence of fatigue and depression in ALS patients and change over time.

BACKGROUND: Amyotrophic lateral sclerosis (ALS) patients report both fatigue and depression. It is not clear how frequently each occurs, to what extent they occur together, how each relates to ALS disease status, or their stability over time. OBJECTIVE: To assess frequency and persistence of fatigue and depression, and relationship to ALS disease status, for patients attending an ALS interdisciplinary centre for routine 3-month visits. METHOD: Measures included the Fatigue Severity Scale, Patient Health Questionnaire-9. ALS Functional Rating Scale -- Revised and forced vital capacity, rate of disease progression, and bulbar/nonbulbar disease onset. RESULTS: 223 patients completed the ratings once; of these, 113 completed them twice, and 65 on three visits. At baseline, 44% (99/223) had clinically significant fatigue, including 34 patients who also had a depressive disorder; 7% (16/223) had major or minor depression only, and 48% (108/223) had neither condition. Fatigue was associated with greater ALS severity, but depression was not. Among the 113 patients seen 3 months later, 75% (33/44) who were fatigued at Time 1 remained fatigued, while 48% (10/21) remained depressed. New-onset fatigue was reported by 22% (25/113), and new-onset depression by 6% (7/113). For the 65 patients seen a third time, rates remained nearly the same. CONCLUSION: Fatigue was more prevalent and persistent than depression, although 15% (34/223) of patients had both conditions. Fatigue but not depression was associated with ALS severity. The two conditions appear to be independent, although sometimes co-occurring, and both warrant consideration in evaluating patient functioning and treatment.

Ceftobiprole: a new beta-lactam antibiotic.

The increasing threat of antimicrobial resistance in general, and that of methicillin-resistant Staphylococcus aureus (MRSA) in particular, is raising significant medical, economical and public health challenges worldwide, both within hospitals and throughout the community. These considerations, along with the extensive time and costs associated with the development and approval of new therapeutic agents, represent some of the major reasons why understanding the advantages and limitations of new antibiotics, ensuring their judicious use and maximising their active shelf life should become global priorities. On March 18, 2008, the Food and Drug Administration issued an approvable letter for ceftobiprole, a broad-spectrum beta-lactam antibiotic active against MRSA and other clinically relevant Gram-positive and Gram-negative pathogens. Ceftobiprole is currently available only for parenteral administration, and besides its remarkable antimicrobial spectrum, this antibiotic possesses additional desirable characteristics, such as low propensity to select for resistance, efficacy in animal models of disease and good safety profile. Furthermore, in recently completed clinical trials, ceftobiprole demonstrated non-inferiority to comparator compounds such as vancomycin, and emerged as a promising clinical option of monotherapy for the treatment of complicated skin and skin structure infections and community-acquired pneumonia. Here, we discuss some of the most important clinically relevant findings on ceftobiprole obtained from in vitro studies, animal models of disease and recently completed phase III clinical trials.

A template for reducing ophthalmology outpatient waiting times: community ophthalmic care.

BACKGROUND: Through an Irish Health Service Executive (HSE) initiative to tackle excessive hospital outpatient waiting times, 996 patients referred to the Ophthalmology Outpatient Department (OPD) of the Mater Misericordiae University Hospital (MMUH), Eccles Street, Dublin 7, Ireland, were outsourced to a community medical eye clinic (CMEC) for consultation with specialist-registered ophthalmologists. AIMS: The study aims to determine if patients referred as routine to the OPD department could be managed in a community setting. METHODS: 996 patients were reviewed in the CMEC, and their data was collected and placed into a spreadsheet for analysis. RESULTS: 61.2% of patients referred to the OPD were fully managed in the community clinic, and 34.9% required ophthalmic surgery in hospital. CONCLUSIONS: By facilitating direct listing of some of the surgical patients to the hospital theatre list, 89.8% of the 996 referrals received treatment without needing to attend the hospital outpatients department.

Depression, distress, lymphocyte subsets, and human immunodeficiency virus symptoms on two occasions in HIV-positive homosexual men.

We evaluated the extent to which depressive disorders, psychiatric distress, and psychosocial stressors are related to three measures of human immunodeficiency virus (HIV) illness, both cross-sectionally and during a 6-month period, in a community sample of 124 HIV-positive homosexual men. The dependent variables are immune status measured by CD4 and CD8 cell subsets, number of signs and symptoms commonly associated with HIV infection, and a cumulative index of HIV illness stage. We chose to focus on CD4 cell count because it is the immune marker most closely linked to the clinical consequences of HIV infection. We found no relationships between the independent variables and immune status or illness stage. The HIV-positive men who were depressed or distressed or who reported more life stressors had no greater immunosuppression or more advanced illness stage than did the others, either concurrently or across occasions. We did find a suggestive pattern of association between depressive disorders, distress, and stressors and the number of HIV-related symptoms, which warrants further study.

Sleep architecture and REM sleep measures in prepubertal major depressives. Studies during recovery from the depressive episode in a drug-free state.

The sleep of 28 fully recovered, drug-free, prepubertal patients with major depressive disorder was recorded for three consecutive nights in the laboratory. Recovered depressives had significantly shorter first rapid eye movement period (REMP) latencies and a higher number of REMPs compared with themselves when depressed and with nondepressed neurotic and normal children. In addition, most sleep continuity measures improved considerably on recovery. We suggest that a short first REMP latency may be a marker of past episode or of trait in prepubertal major depressives.

Electroencephalographic sleep of adolescents with major depression and normal controls.

Forty-nine, mostly outpatient (86%), nonbipolar adolescents, aged Tanner stage III to 18 years, with a current diagnosis of major depressive disorder and 40 adolescents without current presence or history of psychiatric disorder were studied polysomnographically for three consecutive nights. Sleep latency was significantly longer in the depressive groups. The nonendogenous depressive patients exhibited significantly more awake time and lower sleep efficiency during the sleep period. No significant group differences were found for first rapid eye movement (REM) period latency, REM density, or any other REM sleep measures. Age correlated significantly with REM latency and delta sleep time, especially among depressive patients. No significant correlations between sleep measures and severity of illness were found. It appears that the classic REM sleep findings associated with the adult depressive syndrome are not present among depressive adolescents, indicating a later ontogeny for these abnormalities.

Cortisol secretion in prepubertal children with major depressive disorder. Episode and recovery.

Plasma cortisol concentrations were measured every 20 minutes for 24 hours in a group of 45 rigorously assessed, drug-free, prepubertal children who met the unmodified Research Diagnostic Criteria for major depressive disorder (MDD), 20 children with nonaffective psychiatric disorders, and eight normal controls. All children were studied in a low-stress environment. There were no significant differences in plasma cortisol concentration among the three groups as measured by 24-hour mean, peak, nocturnal rise, or nadir values. Division of the MDD group into subgroups based on endogenicity, psychotic symptoms, and suicidality also failed to reveal significant differences for cortisol secretion. Hypersecretion of cortisol (defined as 2 SDs above the grand mean) was identified in only four children with depressive illness and one normal control. Following clinical recovery, 24 depressed children were restudied in a drug-free state and compared with themselves during the episode of illness and with both groups of controls. No significant differences in plasma cortisol concentrations were found. All four depressed hypersecretors were restudied after clinical recovery, and one showed persistence of hypersecretion. These results suggest that abnormalities of cortisol secretion occur infrequently in prepubertal children with major depression when they are studied in a nonstressful environment.

Sleep architecture and REM sleep measures in prepubertal children with major depression: a controlled study.

We performed a three-night polysomnographic study of 54 rigorously assessed, drug free, prepubertal children who fit unmodified Research Diagnostic Criteria for major depressive disorder, and two groups of nondepressed controls (25 with emotional disorders and 11 who were normal). The groups did not differ polysomnographically, even though a high proportion of depressives and neurotics reported sleep disturbance in structured interviews. Sleep stage data do not appear to differentiate children with prepubertal major depressive disorders from nondepressed neurotic or normal children. Other psychobiologic findings in prepubertal depressives together with marked age effects on polysomnographic correlates of adult major depressive disorders suggest the hypothesis that polysomnographic abnormalities in adult major depressives are secondary to an interaction between depression and age.

Panic attacks during placebo procedures in the laboratory. Physiology and symptomatology.

Heart rate, respiratory measurements, and Acute Panic Inventory symptoms of 17 patients with panic disorder who experienced panic attacks during a placebo infusion (situationally provoked panic) were analyzed and compared with similar data from a group of 19 patients with panic disorder who panicked during lactate infusion. Previously, it was shown that the group with lactate-induced panic attacks exhibited increased minute ventilation compared with normal control subjects and nonpanicking patients with panic disorder during lactate infusion. The group with situationally provoked panic attacks exhibited significant increases in both heart rate and minute ventilation immediately preceding the onset of the panic attack. The increase in minute ventilation appeared to be caused more by increase in tidal volume than in respiratory frequency. The increase in heart rate in the group with situationally provoked panic attacks was very similar to that seen in the group with lactate-induced panic attacks, but the group with situationally provoked panic attacks appeared to have somewhat greater increase in minute ventilation than the group with lactate-induced panic attacks. This suggests that the metabolic alkalosis produced by lactate infusion might actually blunt the full expression of panic-associated respiratory stimulation. These data validate the belief that significant cardiorespiratory stimulation occurring during panic attacks in the laboratory is not simply secondary to the intrinsic physiologic effects of panic-inducing substances such as lactate, yohimbine, and carbon dioxide.

Multidisciplinary baseline assessment of homosexual men with and without human immunodeficiency virus infection. I. Overview of study design.

Although much is known about the virus believed by most experts to be the cause of the acquired immunodeficiency syndrome and about its pathogenic actions, major areas of ignorance remain. Among these are the reasons for the varying time between infection with human immunodeficiency virus and development of acquired immunodeficiency syndrome, the relationship between neurologic and medical aspects of the disease, the time course of neuropsychological findings, and the prevalence of psychiatric morbidity. We assessed 124 homosexual men who were positive for human immunodeficiency virus and 84 who were negative for the virus. In this article we describe the study design, method of recruitment, and medical and demographic characteristics of the cohort, which will be followed up for 5 years.

Plasma cortisol concentrations preceding lactate-induced panic. Psychological, biochemical, and physiological correlates.

BACKGROUND: We evaluated the role of plasma cortisol levels in determining sodium lactate-induced panic by reporting psychological, physiological, and biochemical data collected from an extended sample of 214 subjects during the "placebo" infusion (isotonic saline solution) immediately preceding the lactate infusion procedure. METHODS: One hundred seventy patients with panic disorder, 101 (59%) of whom were assessed to have panicked (P group), and 69 (41%) who were assessed not to have panicked (NP group) with lactate infusion; and 44 normal healthy volunteer controls (1 of whom panicked with lactate infusion) were studied. RESULTS: Before the lactate infusion, the P group exhibited hypothalamic-pituitary-adrenal (HPA) axis activation (high plasma cortisol levels) and evidence of hyperventilation (low PCO2 levels) in comparison with NP and control groups. Self-reported fear, dyspnea, and diastolic blood pressure were highest in the P group, intermediate in the NP group, and lowest in the control group. Within the P group, baseline fear scores correlated inversely with PCO2 levels and positively with cortisol levels while PCO2 levels correlated negatively with cortisol levels. Significant predictors of lactate-induced panic were prelactate infusion fear and the interaction of high cortisol levels and low PCO2 levels. CONCLUSION: Combined data suggest that synchronized elevations of HPA axis activity, self-reported fear, and hyperventilation during the period before lactate infusion predisposes to lactate-induced panic.

Personality disorders predict onset of Axis I disorders and impaired functioning among homosexual men with and at risk of HIV infection.

BACKGROUND: A longitudinal study was conducted to investigate whether personality disorders (PDs) increase risk for the development of future Axis I disorders and serious functional impairment among human immunodeficiency virus (HIV)-seropositive and HIV-seronegative homosexual men. METHOD: Baseline assessments of PDs, Axis I disorders and symptoms, and Global Assessments of Functioning were conducted with a community sample of 107 (66 HIV-positive and 41 HIV-negative) homosexual men participating in a longitudinal study with semiannual interviews over 3 years. RESULTS: Logistic regression analysis indicated that PDs predicted onset of subsequent Axis I disorders after controlling for both HIV status and lifetime Axis I history (adjusted odds ratio, 4.31; P=.01; 95% confidence interval, 1.39 to 13.32). Of the 21 participants with PDs, 16 (76%) were subsequently diagnosed with Axis I disorders on at least one occasion. By contrast, only 36 (42%) of the 86 participants without PDs were subsequently diagnosed with Axis I disorders. Further, 33% of the participants with PDs, in comparison with only 8% of those without PDs, were assigned Global Assessments of Functioning scores of 50 or lower, indicating serious impairment during the postbaseline study period (adjusted odds ratio, 5.70; P<.005; 95% confidence interval, 1.66 to 19.53). CONCLUSION: Personality disorders may contribute to increased risk for onset of Axis I disorders and serious impairment among homosexual men regardless of HIV serologic status.

Imipramine in prepubertal major depressive disorders.

The potential effectiveness of imipramine hydrochloride (up to 5 mg/kg/d) was investigated in 53 prepubertal children suffering from major depressive disorder. Two complementary strategies were used simultaneously: a five-week, double-blind, placebo-controlled design (N = 38), and a plasma level/clinical response study (N = 30). Fifteen of the 16 children randomly assigned to active drug in the first study also participated in the second. Subjects were assessed using the Schedule for Affective Disorders and Schizophrenia for School Age Children and diagnosed according to unmodified Research Diagnostic Criteria. Response rates in the double-blind study were similar in both groups (imipramine, 56%; placebo, 68%). In the plasma level study, total maintenance plasma level (imipramine plus desipramine) was found to positively and linearly predict clinical response of the depressive syndrome (P less than .003). No evidence of a curvilinear relationship was found. Depressive hallucinations during the episode negatively predicted clinical response (P less than .05). Weight-corrected imipramine dosage did not predict either clinical response or plasma level in the individual subject. No predictors of response were found in the placebo group. These results suggest that the mean imipramine dosage was too low, and that future double-blind, placebo-controlled studies of imipramine in prepubertal major depression should include plasma level titration to above 150 ng/mL and an initial placebo washout period.

Ventilatory physiology of patients with panic disorder.

Thirty-one patients with DSM-III panic disorder or agoraphobia with panic attacks, 13 normal controls, and 12 patients with other anxiety disorders were studied during ventilatory challenge with room air hyperventilation and 5% carbon dioxide inhalation. Patients also underwent sodium lactate infusion. Among the patients with panic disorder, 58% panicked with sodium lactate, 39% with 5% CO2, and 23% with room air hyperventilation. Of the other patients, four panicked with sodium lactate, none with 5% CO2, and one with room air hyperventilation. One normal control panicked with both sodium lactate and 5% CO2. Panic with CO2 was associated with an exaggerated ventilatory response and increases in plasma norepinephrine level and diastolic blood pressure. Patients with panic disorder may have hypersensitive CO2 receptors that, when triggered, evoke a subjective panic associated with an exaggerated ventilatory response and consequent hypocapnic alkalosis.

A comparison of sodium bicarbonate and sodium lactate infusion in the induction of panic attacks.

Infusion of sodium lactate has been shown by a number of investigators to induce panic in patients with panic disorder, but the pathophysiology underlying this phenomenon is unknown. One theory to explain lactate's anxiety-producing effects involves its ability to induce alkalosis because of metabolic conversion to bicarbonate. To test this hypothesis, we administered both sodium lactate and sodium bicarbonate infusions in counterbalanced order to patients with panic disorder. Thirteen of 22 subjects panicked in response to lactate and nine of 20 subjects panicked in response to bicarbonate. Although the rate of panic between the two infusion responses was not significantly different, several aspects of response to the two infusions indicated that lactate may be a more potent producer of anxiety than bicarbonate. An unexpected finding was that bicarbonate panickers had a reduction in arterial carbon dioxide pressure during the infusion, while bicarbonate nonpanickers had an increase in arterial carbon dioxide pressure during the infusion. Induction of hyperventilation and subsequent hypocapnia appears to be a common denominator between lactate- and bicarbonate-induced panic.

Growth hormone secretion in prepubertal children with major depression. II. Sleep-related plasma concentrations during a depressive episode.

Plasma growth hormone (GH) concentrations were determined every 20 minutes during sleep in 71 prepubertal children: 22 had endogenous major depressive disorder, 20 had nonendogenous major depressive disorder, 21 had nondepressed neurotic disorders, and eight were normal. Both depressive groups secreted significantly more GH during sleep than did controls. Measures included maximal GH plasma peak and area under the curve (AUC) during the total sleep period, during the first three hours after sleep onset, and during the first five hours after sleep onset. An AUC cutoff of 2,000 ng X min/mL identified positively half the prepubertal children with major depression; with a specificity of 78% (v neurotics) and 100% (v normal children). Increased GH secretion during sleep may be a marker of illness, a past episode, or trait for prepubertal major depression regardless of endogenicity.

Growth hormone secretion in prepubertal children with major depression. IV. Sleep-related plasma concentrations in a drug-free, fully recovered clinical state.

Prepubertal children with major depressive disorder have shown increased growth hormone (GH) secretion during sleep while in a depressive episode. When restudied in a fully recovered state (for at least three months) and drug free (for at least one month), their increased GH secretory pattern during sleep had not changed. Illness-recovery correlations using area under the curve for GH secretion during sleep were highly significant, whereas paired comparisons showed no significant differences. In addition, children who had recovered from major depressive episodes secreted significantly more GH during sleep than did nondepressed neurotic and normal children. No significant differences in delta-sleep were found in the depressed group between ill and recovered states nor among those who had recovered from major depressive episodes or controls. It is concluded that increased GH secretion during sleep is independent of depressive episodes, remains unaltered after full recovery, and may be a true marker of trait for major depressive disorder in prepuberty.