First Measurement of Hard Exclusive π^{-}Δ^{++} Electroproduction Beam-Spin Asymmetries off the Proton

The polarized cross-section ratio σ_{LT^{'}}/σ_{0} from hard exclusive π^{-}Δ^{++} electroproduction off an unpolarized hydrogen target has been extracted based on beam-spin asymmetry measurements using a 10.2  GeV/10.6  GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. The study, which provides the first observation of this channel in the deep-inelastic regime, focuses on very forward-pion kinematics in the valence regime, and photon virtualities ranging from 1.5  GeV^{2} up to 7  GeV^{2}. The reaction provides a novel access to the d-quark content of the nucleon and to p→Δ^{++} transition generalized parton distributions. A comparison to existing results for hard exclusive π^{+}n and π^{0}p electroproduction is provided, which shows a clear impact of the excitation mechanism, encoded in transition generalized parton distributions, on the asymmetry.

Center of Mass Motion of Short-Range Correlated Nucleon Pairs studied via the A(e,e^{'}pp) Reaction

Short-range correlated (SRC) nucleon pairs are a vital part of the nucleus, accounting for almost all nucleons with momentum greater than the Fermi momentum (k_{F}). A fundamental characteristic of SRC pairs is having large relative momenta as compared to k_{F}, and smaller center of mass (c.m.) which indicates a small separation distance between the nucleons in the pair. Determining the c.m. momentum distribution of SRC pairs is essential for understanding their formation process. We report here on the extraction of the c.m. motion of proton-proton (pp) SRC pairs in carbon and, for the first time in heavier and ansymetric nuclei: aluminum, iron, and lead, from measurements of the A(e,e^{'}pp) reaction. We find that the pair c.m. motion for these nuclei can be described by a three-dimensional Gaussian with a narrow width ranging from 140 to 170  MeV/c, approximately consistent with the sum of two mean-field nucleon momenta. Comparison with calculations appears to show that the SRC pairs are formed from mean-field nucleons in specific quantum states.

Absence of Anemia in Maintenance Hemodialysis

Anemia is usual in untreated uremia. Persistent anemia is thought to be universal in uremic patients treated by maintenance hemodialysis (MH). A retrospective chart analysis of 549 patients on (MH) at five facilities in Brooklyn, found that eleven (2%) of these patients had a hematocrit (Hct) in the normal range (40%). To distinguish this subset of patients from the majority of MH, we compared both groups for: (1) etiology of the renal disease, (2) presence of residual renal function, (3) dialysis prescription, (4) decreased arterial O2 saturation, (5) greater use of vitamins or anabolic steroids, (6) absence of parathyroid disease. The relatively high hematocrit was not explained by any factor evaluated in this small subset of MH patients.

Measurement of the Q^{2} Dependence of the Deuteron Spin Structure Function g_{1} and its Moments at Low Q^{2} with CLAS

We measured the g_{1} spin structure function of the deuteron at low Q^{2}, where QCD can be approximated with chiral perturbation theory (χPT). The data cover the resonance region, up to an invariant mass of W≈1.9  GeV. The generalized Gerasimov-Drell-Hearn sum, the moment Γ_{1}^{d} and the spin polarizability γ_{0}^{d} are precisely determined down to a minimum Q^{2} of 0.02  GeV^{2} for the first time, about 2.5 times lower than that of previous data. We compare them to several χPT calculations and models. These results are the first in a program of benchmark measurements of polarization observables in the χPT domain.

First Exclusive Measurement of Deeply Virtual Compton Scattering off ^{4}He: Toward the 3D Tomography of Nuclei

We report on the first measurement of the beam-spin asymmetry in the exclusive process of coherent deeply virtual Compton scattering off a nucleus. The experiment uses the 6 GeV electron beam from the Continuous Electron Beam Accelerator Facility (CEBAF) accelerator at Jefferson Lab incident on a pressurized ^{4}He gaseous target placed in front of the CEBAF Large Acceptance Spectrometer (CLAS). The scattered electron is detected by CLAS and the photon by a dedicated electromagnetic calorimeter at forward angles. To ensure the exclusivity of the process, a specially designed radial time projection chamber is used to detect the recoiling ^{4}He nuclei. We measure beam-spin asymmetries larger than those observed on the free proton in the same kinematic domain. From these, we are able to extract, in a model-independent way, the real and imaginary parts of the only ^{4}He Compton form factor, H_{A}. This first measurement of coherent deeply virtual Compton scattering on the ^{4}He nucleus, with a fully exclusive final state via nuclear recoil tagging, leads the way toward 3D imaging of the partonic structure of nuclei.

Beam-Target Helicity Asymmetry for γ[over →]n[over →]→π^{-}p in the N^{*} Resonance Region

We report the first beam-target double-polarization asymmetries in the γ+n(p)→π^{-}+p(p) reaction spanning the nucleon resonance region from invariant mass W=1500 to 2300 MeV. Circularly polarized photons and longitudinally polarized deuterons in solid hydrogen deuteride (HD) have been used with the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. The exclusive final state has been extracted using three very different analyses that show excellent agreement, and these have been used to deduce the E polarization observable for an effective neutron target. These results have been incorporated into new partial wave analyses and have led to significant revisions for several γnN^{*} resonance photocouplings.

Cross Sections for the Exclusive Photon Electroproduction on the Proton and Generalized Parton Distributions

Unpolarized and beam-polarized fourfold cross sections (d^{4}σ/dQ^{2}dx_{B}dtdϕ) for the ep→e^{'}p^{'}γ reaction were measured using the CLAS detector and the 5.75-GeV polarized electron beam of the Jefferson Lab accelerator, for 110 (Q^{2},x_{B},t) bins over the widest phase space ever explored in the valence-quark region. Several models of generalized parton distributions (GPDs) describe the data well at most of our kinematics. This increases our confidence that we understand the GPD H, expected to be the dominant contributor to these observables. Through a leading-twist extraction of Compton form factors, these results support the model predictions of a larger nucleon size at lower quark-momentum fraction x_{B}.

Towards a resolution of the proton form factor problem: new electron and positron scattering data

There is a significant discrepancy between the values of the proton electric form factor, G(E)(p), extracted using unpolarized and polarized electron scattering. Calculations predict that small two-photon exchange (TPE) contributions can significantly affect the extraction of G(E)(p) from the unpolarized electron-proton cross sections. We determined the TPE contribution by measuring the ratio of positron-proton to electron-proton elastic scattering cross sections using a simultaneous, tertiary electron-positron beam incident on a liquid hydrogen target and detecting the scattered particles in the Jefferson Lab CLAS detector. This novel technique allowed us to cover a wide range in virtual photon polarization (ϵ) and momentum transfer (Q(2)) simultaneously, as well as to cancel luminosity-related systematic errors. The cross section ratio increases with decreasing ϵ at Q(2)=1.45  GeV(2). This measurement is consistent with the size of the form factor discrepancy at Q(2)≈1.75  GeV(2) and with hadronic calculations including nucleon and Δ intermediate states, which have been shown to resolve the discrepancy up to 2-3  GeV(2).

Longitudinal target-spin asymmetries for deeply virtual compton scattering

A measurement of the electroproduction of photons off protons in the deeply inelastic regime was performed at Jefferson Lab using a nearly 6 GeV electron beam, a longitudinally polarized proton target, and the CEBAF Large Acceptance Spectrometer. Target-spin asymmetries for ep→e^{'}p^{'}γ events, which arise from the interference of the deeply virtual Compton scattering and the Bethe-Heitler processes, were extracted over the widest kinematics in Q^{2}, x_{B}, t, and ϕ, for 166 four-dimensional bins. In the framework of generalized parton distributions, at leading twist the t dependence of these asymmetries provides insight into the spatial distribution of the axial charge of the proton, which appears to be concentrated in its center. These results also bring important and necessary constraints for the existing parametrizations of chiral-even generalized parton distributions.

Strangeness suppression of qq creation observed in exclusive reactions

We measured the ratios of electroproduction cross sections from a proton target for three exclusive meson-baryon final states: ΛK(+), pπ(0), and nπ(+), with the CLAS detector at Jefferson Lab. Using a simple model of quark hadronization, we extract qq creation probabilities for the first time in exclusive two-body production, in which only a single qq pair is created. We observe a sizable suppression of strange quark-antiquark pairs compared to nonstrange pairs, similar to that seen in high-energy production.

Characterization of hyperkalemic periodic paralysis: a survey of genetically diagnosed individuals

This exploratory study aims to create an evidence-based comprehensive characterization of hyperkalemic periodic paralysis (hyperPP). HyperPP is a rare genetic disorder that causes episodes of flaccid paralysis. Disease descriptions in the literature are based upon isolated clinical encounters and case reports. We describe the experience of a large cohort of genetically diagnosed individuals with hyperPP. We surveyed genetically characterized individuals age 18 and over to assess disease comorbidities, diagnostic testing, management, and quality of life issues relevant to hyperPP. Myotonia was reported by 55.8 % of subjects and paramyotonia by 45.3 %. There is a relative risk of 3.6 (p < 0.0001) for thyroid dysfunction compared to the general population. Twenty-five percent of subjects experienced their sentinel attack in the second decade of life. It took an average of 19.4 years and visits to four physicians to arrive at the diagnosis of hyperPP. In addition to limbs and hands being affected during attacks, 26.1 % of subjects reported their breathing musculature was affected and 62.0 % reported their facial muscles were affected. There was a lifelong trend of increasing attack frequency, which was particularly common during childhood and adolescence. Approximately one-third of individuals experienced progressive myopathy. Permanent muscle weakness was evident and worsened during childhood and after age 40. Those with no chronic treatment regimen have a RR of 2.3 for inadequate disease control compared to those taking long-term medications. This study revealed a multitude of heretofore unidentified characteristics of hyperPP, in addition to providing a different perspective on some previously held notions regarding the condition.

Hard two-body photodisintegration of 3He

We have measured cross sections for the γ(3)He → pd reaction at photon energies of 0.4-1.4 GeV and a center-of-mass angle of 90°. We observe dimensional scaling above 0.7 GeV at this center-of-mass angle. This is the first observation of dimensional scaling in the photodisintegration of a nucleus heavier than the deuteron.

Measurement of exclusive π(0) electroproduction structure functions and their relationship to transverse generalized parton distributions

Exclusive π(0) electroproduction at a beam energy of 5.75 GeV has been measured with the Jefferson Lab CLAS spectrometer. Differential cross sections were measured at more than 1800 kinematic values in Q(2), x(B), t, and ϕ(π), in the Q(2) range from 1.0 to 4.6  GeV(2), -t up to 2  GeV(2), and x(B) from 0.1 to 0.58. Structure functions σ(T)+ϵσ(L), σ(TT), and σ(LT) were extracted as functions of t for each of 17 combinations of Q(2) and x(B). The data were compared directly with two handbag-based calculations including both longitudinal and transversity generalized parton distributions (GPDs). Inclusion of only longitudinal GPDs very strongly underestimates σ(T)+ϵσ(L) and fails to account for σ(TT) and σ(LT), while inclusion of transversity GPDs brings the calculations into substantially better agreement with the data. There is very strong sensitivity to the relative contributions of nucleon helicity-flip and helicity nonflip processes. The results confirm that exclusive π(0) electroproduction offers direct experimental access to the transversity GPDs.

Measurement of the neutron F2 structure function via spectator tagging with CLAS

We report on the first measurement of the F(2) structure function of the neutron from the semi-inclusive scattering of electrons from deuterium, with low-momentum protons detected in the backward hemisphere. Restricting the momentum of the spectator protons to ≲100 MeV/c and their angles to ≳100° relative to the momentum transfer allows an interpretation of the process in terms of scattering from nearly on-shell neutrons. The F(2)(n) data collected cover the nucleon-resonance and deep-inelastic regions over a wide range of Bjorken x for 0.65<Q(2)<4.52 GeV(2), with uncertainties from nuclear corrections estimated to be less than a few percent. These measurements provide the first determination of the neutron to proton structure function ratio F(2)(n)/F(2)(p) at 0.2≲x≲0.8 with little uncertainty due to nuclear effects.

Comparison of community residential supports on measures of information & planning; access to & delivery of supports; choice & control; community connections; satisfaction; and, overall perception of outcomes

BACKGROUND

This paper reports on some of the findings of a large-scale survey (n = 852) of family members and support staff of adults with intellectual disabilities receiving community living services in British Columbia, Canada, concentrating on comparison of outcomes across four types of community residential settings: group homes, family model homes, independent home or apartment, and family home.

METHOD

Comparisons were conducted on six domains: information and planning; access to and delivery of supports; choice and control; community connections; satisfaction; and, overall perception of outcomes. Where applicable, further multivariate analyses were undertaken to determine the effect of the degree of help required by the residents and the respondent type.

RESULTS

Findings indicate that on all measures other than choice and control, group homes and family model homes showed better outcomes than either independent settings or family homes.

CONCLUSION

The findings may indicate that the move to more independent living settings is not being accompanied by appropriate supports.

Cauliflower somatic embryogenesis and analysis of regenerant stability by ISSRs

  To study the somatic embryogenesis of Brassica oleracea var. botrytis L., hypocotyls were placed on Murashige and Skoog's medium (1962) with 1 mg.l^-1 of 2,4-dichlorophenoxyacetic acid and 1 mg.l^-1 of kinetin to induce callogenesis. After transfer of the calli to the maturation medium, somatic embryos appeared. They developed into plantlets and the potential of regeneration of the calli was maintained for more than 8 months. Thirty-five plantlets were produced after 2 months of culture, then transplanted into soil. Inter-simple sequence repeat markers generated by trinucleotidic and tetranucleotidic primers were tested for their ability to characterise genomic variations in the obtained plants. The absence of polymorphism between different regenerants from the same cultivar indicates the conformity of the regeneration protocol.

IDS-C and IDS-sr: psychometric properties in depressed in-patients

Sixty-eight depressed in-patients were assessed at admission (DO), and after 5 days (D5), ten days (D10) and 28 days (D28) of antidepressant treatment, with the Inventory for Depressive Symptomatology-Clinician (IDS-C) and the Inventory for Depressive Symptomatology-Self-Rated (IDS-SR) (Rush et al., 1986), the Montgomery and Asberg Depression Rating Scale (MADRS) (Montgomery and Asberg, 1979) and the depression factor of the Symptom Check List (SCL-90R) (Derogatis, 1977), in order to assess IDS-C and IDS-SR psychometric properties in depressed in-patients and to compare IDS-C to MADRS and IDS-SR to the SCL-90R depression factor. Most of the IDS-C and IDS-SR items were significantly correlated to the final score and the Cronbach alpha coefficients were high (0.75 for the IDS-C and 0.79 for the IDS-SR). Principal Component Analyses (PCA) showed three factors for both IDS-C and IDS-SR: 'depression', 'anxiety/arousal' and 'sleep/appetite'. These results suggest satisfactory internal consistency of IDS-C and IDS-SR. Concurrent validity of the IDS-C with the MADRS was high (r = 0.81), as well as concurrent validity of the IDS-SR with the SCL-90R depression factor (r = 0.84). Concerning sensitivity to change, the four scales were able to discriminate between different levels of severity of depression. Moreover, considering paired t-tests on score changes, IDS-C sensitivity to change may be higher than MADRS sensitivity to change, this phenomenon being related to the number of items and degrees but not to the item contents. Contrary to IDS-C and MADRS, IDS-SR and SCL-90R depression factor were not different in terms of sensitivity to change. Finally, psychometric properties of IDS-C and IDS-SR in depressed in-patients are satisfactory and close to those obtained in depressed out-patients. The high sensitivity to change of the IDS-C may be an advantage for this scale as compared to the MADRS, especially in antidepressant drug trials.

Synthesis of 25-aminosterols, new antifungal agents

25-aminolanostenol 1 and 25-aminocholesterol 2 were hemisynthesized from natural sterols and tested in vitro against Candida albicans. The biological activity of compound 1 was rather weak, whereas 2 exhibited in vitro antifungal activity with MIC value of 4 microM.

Synthesis of 6(alpha, beta)-aminocholestanols as ergosterol biosynthesis inhibitors

delta 7-5-Desaturase catalyses one of the last steps in ergosterol biosynthesis in fungi. Moreover delta 5-unsaturation is necessary for the sparking function. Synthesis of three pairs of C-6 epimeric cholestanol derivatives are described as potential growth inhibitors. Preliminary results suggest that 6 beta-aminocholestanol is a potent antifungal agent.

Lithium compared to valproic acid and carbamazepine in the treatment of mania: a statistical meta-analysis

The hypothesis that lithium is the most appropriate and efficacious pharmacological treatment in the therapy of manic-depressive illness was examined in a meta-analysis. The efficacy of lithium was compared with that of the antiepileptics, carbamazepine and valproic acid. Data sources include the Medline database and relevant references from articles. Only randomised controlled clinical trials with a double-blind assessment of outcomes were included. Lithium levels were required to be within the therapeutic range of 0.4-1.5 mmol/l. The effect sizes were measured by the odds ratio using the Mantel-Haenszel method. No significant difference was observed between the treatment effect of the 3 drugs compared. While the efficacy of the 3 treatments was identical, there is a general tendency in favour of the antiepileptics in the treatment of manic depression with regard to adverse events and treatment tolerance. The impact and importance of this study seriously question the relevance of today's practice of prescribing lithium in the acute management of manic-depressive illness.

Lithium therapy in the treatment of manic-depressive illness. Present status and future perspectives. A critical review

This article reviews critically the present status of lithium in the treatment and prophylaxis of manic-depressive illness compared to the two anticonvulsant drugs, carbamazepine and valproic acid. Lithium is used successfully in the prophylaxis and treatment of manic-depression. The mechanism by which it exerts its effects is still not very clear. There is much evidence to indicate that lithium may exert its therapeutic action by interfering with the metabolism of phosphoinositides which play an important role in synaptic transmission. Because of lithium's narrow therapeutic/toxic ratio, blood concentration monitoring is crucial. Published data suggest that, compared to lithium, carbamazepine is similar in its relative specificity in treating mania. It is often faster in achieving its antimanic effects and best established as an alternative for patients not responding or intolerant to lithium. Carbamazepine is a good substitute for lithium when severe renal problems exclude the use of lithium. The therapeutic profile of valproic acid in manic-depression, although less extensively studied, appears to be similar to that of carbamazepine. As carbamazepine, it seems to be best indicated in patients with rapid cycles. Whereas lithium inhibits myo-inositol monophosphatase, carbamazepine shows a stimulating effect and valproic acid has no effect on this biochemical target. The implication of the inositol pathway in the pathogenesis of adverse effects, such as neurotoxicity and dermatological irritation, is discussed. A further understanding of this pathway is important for the future development of new lithium-like compounds in order to maximize the therapeutic benefits without the adverse effects.

Efficacy of the 'clonidine REM suppression test (CREST)' to separate patients with major depression from controls; a comparison with three currently proposed biological markers of depression

We have shown that clonidine, infused i.v. during the second non-REM period, was significantly less REM sleep suppressant in depressed patients than in control subjects. We have named this procedure the 'clonidine REM suppression test (CREST)'. In this report, we compare in the same sample (15 patients with primary major affective illness, 10 normal controls, 15 patients with minor depression and 15 patients with generalized anxiety) the efficacy of the CREST to separate the major depressed patients from the control subjects with the efficacy of three currently proposed biological markers of depression, i.e., the latency of REM sleep, the dexamethasone suppression test and the clonidine growth hormone stimulation test. We found that the CREST had the highest efficacy and suggest that further studies with independent and larger samples of patients and controls are needed to confirm those preliminary results and establish if the CREST could provide a new biological marker of major affective disorders.

[Congestive pelvic syndromes]

Pelvic congestion syndrome is encountered in three pathological situations: premenstrual syndrome, intermenstrual syndrome, chronic pelvic congestion syndrome. The first two syndromes, with a range of physical and/or psychological symptoms, are cyclical. Their pathogenesis is multifactorial. Hormonal and circulatory factors are essentially blamed. Treatment is most often based upon combinations of progestogens and venotonics. The third syndrome, that of chronic pelvic congestion, is characterised by long term pelvic pain and raises etiopathogenic problems which remain only partially solved and in which a vascular role may sometimes be recognised. Endovaginal ultrasonography with colour-coded Doppler and celioscopy sometimes reveal pelvic varicose veins and indicate their responsibility for such pain, after having eliminated specific pelvic pathology (post-infectious or post-operative inflammatory sequelae of pelvic tissue, rupture of the broad ligaments, endometriosis, etc.). Treatment is above all medical, based upon hormone therapy acting upon venous receptors, venotonics which decrease the consequences of stasis, intermittent courses of anti-inflammatory agents and antibiotics when there is inflammation secondary to local infection. These various types of treatment may be combined. Surgical treatment should be restricted to certain carefully assessed cases only.

P300 in posttraumatic stress disorder

In the present study, P300 has been recorded in 26 subjects (15 women) 1 month after an aggression without organic complications. Among our sample, 16 subjects fulfilled DSM-III-R criteria for posttraumatic stress disorder (PTSD) and 10 did not. P300 amplitude was significantly lower in the 16 PTSD subjects as compared to the 10 subjects without PTSD. This study supports information processing disturbances in PTSD.

[Role of MRI in pre-clinical breast lesions. Preliminary results]

The purpose of this study is to assess the value of MR imaging in nonpalpable breast tumors. Thirty-two women whose mammogram showed opacity, architectural distorsionor microcalcifications, underwent preoperative dynamic MR studies with quantitative evaluation of contrast enhancement. MR showed early contrast enhancement in 10/12 breast cancers (2 false-negative) and in 6/20 benign lesions (false-positive). Quantitative study of contrast enhancement does not allow clear differentiation between these lesions. Further studies are required to confirm these findings and purpose MR imaging for aid in detection of carcinomas. Multifocal sudden enhancements are possible in benign lesions and incite to limit MR to focal mammographic abnormalities.

Controlled comparison of milnacipran and fluoxetine in major depression

The efficacy and the tolerance of milnacipran (100 mg/day), a second generation antidepressant which equipotently inhibits both noradrenaline and serotonin reuptake, was compared to fluoxetine (20 mg/day), a selective serotonin reuptake inhibitor, in two parallel groups of, respectively, 97 and 93 major depressive outpatients. The duration of the study was 6 weeks, with assessments every 2 weeks by means of the Montgomery and Asberg depression scale (MADRS), the Hamilton depression scale, the clinical global impressions (CGI), and a checklist of symptoms and side-effects. Results showed significant superiority of fluoxetine over milnacipran on most rating instruments: MADRS (P = 0.01) including five individual items, Hamilton depression scale (P = 0.002) including ten individual items, CGI of severity (P = 0.01) and therapeutical index (P = 0.002). On visual analogue scales assessing the clinical profile of the compounds, fluoxetine was rated as exhibiting more psychostimulating activity than milnacipran (P = 0.0008). The tolerance of the two antidepressants was very similar, with the exception of symptoms of dizziness which were more frequently reported with milnacipran (P = 0.01). These differences in efficacy favoring fluoxetine could result from the selection of a dose of milnacipran below the optimal therapeutic dose for this type of psychiatric patients or to the administration of the compounds in single daily intakes, whereas milnacipran possesses a plasma elimination half-life of only 7 h.

Effects of gender and diagnosis on growth hormone response to clonidine for major depression: a large-scale multicenter study

OBJECTIVE

The authors' goal was to establish, in a large multicenter sample of patients classified according to gender and menopausal status, if the growth hormone (GH) response to clonidine discriminated patients with episodes of major depression from patients with episodes of minor depression.

METHOD

The GH response to intravenous clonidine administration (150 micrograms) was compared in 71 male and 140 female patients with major depressive episodes and 47 male and 53 female patients with minor depressive episodes. These patients were diagnosed according to Research Diagnostic Criteria.

RESULTS

Differences in the GH response to clonidine between diagnostic groups occurred only between male patients. These results were found in the group as a whole and in each center. The GH responses to clonidine of premenopausal women differed significantly from those of postmenopausal women in each diagnostic group.

CONCLUSIONS

These results confirm that gender and menopausal status are of the utmost importance in the interpretation of the clonidine GH test.

Prognosis of mechanically ventilated patients

In this Department of Veterans Affairs cooperative study, we examined predictors of in-hospital and 1-year mortality of 612 mechanically ventilated patients from 6 medical intensive care units in a retrospective cohort design. The outcome variable was vital status at hospital discharge and after 1 year. The results showed that 97% of patients were men, the mean age was 63 +/- 11 years (SD), and hospital mortality was 64% (95% confidence interval, 60% to 68%). Within the next year, an additional 38% of hospital survivors died, for a total 1-year mortality of 77% (95% confidence interval, 73% to 80%). Hospital and 1-year mortality, respectively, for patients older than 70 years was 76% and 94%, for those with serum albumin levels below 20 grams per liter it was 92% and 96%, for those with an Acute Physiology and Chronic Health Evaluation II (APACHE II) score greater than 35 it was 91% and 98%, and for patients who were being mechanically ventilated after cardiopulmonary resuscitation it was 86% and 90%. The mortality ratio (actual mortality versus APACHE II-predicted mortality) was 1.15. Conclusions are that patient age, APACHE II score, serum albumin levels, or the use of cardiopulmonary resuscitation may identify a subset of mechanically ventilated veterans for whom mechanical ventilation provides little or no benefit.

Growth hormone response to clonidine in male patients with panic disorder untreated by antidepressants

We report a non-significantly higher growth hormone (GH) response to intravenous clonidine administration (150 micrograms) in 10 male patients with panic disorder who had never received antidepressant therapy than in 10 matched controls. These results are consistent with data suggesting a normal or increased adrenergic receptor sensitivity in panic disorder patients.

Use of traditional and modern health services by Laotian refugees

Although refugee health care emerged as a special interest in the United States following the influx of almost a million Southeast Asians since 1975, few studies have been done of the influence of refugee traditions on the use of Western medical services. The illness patterns, medical beliefs, and health care behavior of a Southeast Asian refugee group, the Mien from Laos are described in this study. A cohort of 119 Mien refugees living in Richmond, California, was observed for a 6-month period. In-home interviews were undertaken about all episodes of ill health, including treatment and health care decisions. This study shows that the Mien integrate traditional healing beliefs and practices with the use of American health services. Such findings are important because the increasing cultural diversity in the United States, particularly in Western states, necessitates that health care professionals understand the importance of cultural factors for access to and the use of health care by all patients including refugees and other immigrant groups.

Reduced clonidine rapid eye movement sleep suppression in patients with primary major affective illness

Clonidine hydrochloride, administered intravenously (2 micrograms/kg) during the second non-rapid eye movement period, was significantly less suppressant of rapid eye movement sleep in 10 depressed patients with primary major affective illness, according to Research Diagnostic Criteria, than in three groups of matched subjects (10 normal controls, 10 patients with minor depression, and 10 patients with generalized anxiety). These results suggest that depressed patients with major primary affective illness have down-regulated alpha 2-adrenergic receptors. These findings are consistent with the cholinergic-aminergic balance hypothesis of depression and support the aminergic side of the concept. Finally, the rapid eye movement sleep response to clonidine could provide a new biological marker of affective illness.

[P 300 slow potential. Clinical interest in 3 mental diseases and neurobiology: a review]

P300 is a late component of evoked potential which meet special relevance to the study of cognitive processes. P300 indexes categorization processes and the context updating of memory. Its latency reflects the stimulus evaluation time, and P300 amplitude is related to some psychological variables such as expectancy, attention and stimulus significance. In this review, clinical correlation between P300 components and mental diseases are reported, especially dementia, schizophrenia and depression. Delayed P300 latency has been found in Alzheimer disease and in other forms of dementia. Reduced P300 amplitude as well as altered topography has been reported in schizophrenia. In depression, reduced P300 amplitude has been related with longer reaction time. Unfortunately, the diagnosis utility of P300 seems limited. The authors also propose an overview of the actual knowledge on neurobiological findings in the generation of the P300 wave. Anatomical data point out the importance of the limbic system, more specifically, of the hippocampus and the locus coeruleus, in generating and modulating P300 wave. Data from the literature on the psychopharmacological modifications induced by cholinergic, catecholaminergic and other agents, are reviewed. Although the dopaminergic and noradrenergic systems are of some importance, these data emphasise the importance of the cholinergic system for the generation and modulation of P300 amplitude and latency. The value and interpretation of these neurobiological and clinical findings are discussed.

Lymphocyte subsets in major depressive patients. Influence of anxiety and corticoadrenal overdrive

We studied 26 inpatients (17 females; mean age +/- SD: 41.2 +/- 14.3 years) who met the DSM III criteria for a major depressive episode and had a mean (+/- SD) Hamilton Depression Score of 19.3 +/- 8.0. All patients were drug free and medically healthy at the time of experimentation. We found a significant correlation between the CD4/CD8 ratio and the Hamilton Anxiety Score (r = 0.57, p less than 0.005). When splitting our sample in dexamethasone suppression test suppressors (DST-S) and nonsuppressors (DST-NS), this relationship appeared only in DST-NS (DST-NS: r = 0.81, p less than 0.005; DST-S: r = 0.20, p = NS). These results are discussed in terms of heterogeneity among major depressive disorders and possible relationships between catecholaminergic activity and the immune system.

How strictly do dialysis patients want their advance directives followed?

OBJECTIVE

The Cruzan case and the Patient Self-Determination Act will encourage patients to specify in advance which life-sustaining treatments they would want if they become mentally incompetent. However, strictly following such advance directives may not always be in a patient's best interests. We sought to determine whether patients differ in how strictly they want advance directives followed.

DESIGN

Interview study.

SETTING

Seven outpatient chronic dialysis centers.

PARTICIPANTS

One hundred fifty mentally competent dialysis patients.

INTERVENTION

Using a structured questionnaire, we asked the subjects whether they would want dialysis continued or stopped if they developed advanced Alzheimer's disease. We then asked how much leeway their physician and surrogate should have to override that advance directive if overriding were in their best interests. Subjects granting leeway were also asked what factors should be considered in making decisions for them.

RESULTS

Subjects varied greatly in how much leeway they would give surrogates to override their advance directives: "no leeway" (39%), "a little leeway" (19%), "a lot of leeway" (11%), and "complete leeway" (31%). Subjects also varied in how much they wanted various factors considered in making decisions, such as pain or suffering, quality of life, possibility of a new treatment, indignity caused by continued treatment, financial impact of treatment on family members, and religious beliefs.

CONCLUSIONS

Strictly following all advance directives may not truly reflect patients' preferences. To improve advance directives, we recommend that physicians explicitly ask patients how strictly they want their advance directives followed and what factors they want considered in making decisions.

Intraoperative radiation therapy for recurrent head and neck cancer

Forty-seven patients with recurrent head and neck cancer in a previously irradiated field were treated with surgical resection and intraoperative radiation therapy (IORT). Recurrent disease occurred at a median of 18 months from primary treatment, and was at the primary tumor site in 31 and metastatic to regional lymph nodes in 16. Recurrences were squamous cell carcinomas in 42 and adenoid cystic in five. Surgical resection left microscopic residual disease in 41 and gross residual in six. All patients received IORT with a median of 20 Gy. Two-year actuarial survival is 54.9%, and 15 patients are alive and disease free with a median survival of 29 months. Two-year actuarial local control is 61.5%. A trend toward increased survival (P less than 0.09) and local recurrence control (P = 0.05) was noticed when treating microscopic residual disease as opposed to gross residual disease. Perioperative mortality was seen in 8.5% and there was no increase in morbidity secondary to IORT. The authors believe that surgical resection and IORT is an effective treatment modality for head and neck cancers recurrent in previously irradiated fields and is adaptable to tertiary care hospitals.

Latencies of REM sleep and awakening in major depression: possible indicators of cholinergic activity

REM latency and awakening latency were analyzed in a sample of 26 major depressive inpatients and 8 male controls recorded for two consecutive nights. A significant inverse relationship appeared between REM latency and awakening latency in depressed patients. The relationship was more marked in male than in female patients. No significant correlation between REM latency and awakening latency was observed in male healthy volunteers. The hypothetical cholinergic supersensitivity in major depression is proposed to explain the present relationship. These results suggest that awakening latency might also be taken into account in the evaluation of sleep disturbances in depressive illness.

Growth hormone response to clonidine in untreated depressed patients

Growth hormone (GH) responses to i.v. clonidine administration (150 micrograms) were compared in untreated depressed patients and controls. There were 8 controls (6 males, 2 females), 16 patients with a major depressive episode (8 males, 8 females), and 16 matched patients with a minor depressive episode according to Research Diagnostic Criteria. Differences in the GH response to clonidine only occurred between male patients and controls. These results suggest that endocrinological variables are important in the interpretation of this neuroendocrine test. Findings in the subgroup of unmedicated male patients with a nonendogenous major depressive episode support the hypothesis of decreased noradrenergic receptor sensitivity.

Tricyclic wash-out and growth hormone response to clonidine

We have observed a significantly higher growth hormone (GH) response to clonidine administration (150 micrograms i.v.) in 14 patients with a major depressive disorder who had never received antidepressant therapy than in 14 matched depressive patients who had not received tricyclic drugs for at least 15 days. Compared with a control group of eight subjects, untreated depressed patients, as a group, had a normal response, while matched patients had markedly blunted response. Results for the group of untreated depressed patients showed that some patients had a blunted response while others had a response in the normal range. The results suggest that studies on the GH response to clonidine in psychiatric patients need to take into account the confounding and long-lasting effects of tricyclics.

Primary mitochondrial activity of gossypol in yeast and mammalian cells

Gossypol showed primary antimitochondrial activity in yeast cells in that the drug (1) inhibited growth of cells utilizing mitochondrial substrates as carbon and energy sources, and (2) selectively inhibited mitochondrial protein synthesis. Primary antimitochondrial activity was demonstrated in guinea-pig keratinocytes (GPK) by early arrest of growth and loss of viability in medium with glutamine (a mitochondrial substrate) as carbon and energy source compared with cells utilizing glucose. Gossypol depressed oxygen uptake directly in respiring cells. Gossypol interacted with the known antimitochondrial agents ethidium bromide and 5-fluorouracil (FU), potentiating the activity of FU but reversing that of ethidium bromide in yeast and GPK. Also, the activity of the mitochondrial inhibitor oligomycin was reversed by the presence of gossypol in yeast cells but not tested in GPK. The uptake and retention of the mitochondria-specific dye rhodamine 123 were much depressed by gossypol in GPK. Gossypol showed little or no inhibitory effects in yeast or GPK in the presence of ethanol (0.2-0.5%). The drug was not mutagenic with respect to the yeast mitochondrial system. It was tentatively suggested that mitochondrial perturbation could explain the antifertility effect of gossypol if it is assumed that mitochondria have a special role to play in spermatogenesis and sperm motility, making these tissues more sensitive to mitochondrial inhibitors than somatic cells.