Enhanced monsoon precipitation and nitrogen deposition affect leaf traits and photosynthesis differently in spring and summer in the desert shrub Larrea tridentata.

Leaf-level CO2 assimilation (A(area)) can largely be predicted from stomatal conductance (g(s)), leaf morphology (SLA) and nitrogen (N) content (N(area)) in species across biomes and functional groups. The effects of simulated global change scenarios, increased summer monsoon rain (+H2O), N deposition (+N) and the combination (+H2O +N), were hypothesized to affect leaf trait-photosynthesis relationships differently in the short- and long-term for the desert shrub Larrea tridentata. During the spring, +H2O and +H2O +N plants had lower A(area) and g(s), but similar shoot water potential (Psi(shoot)) compared with control and +N plants; differences in A(area) were attributed to lower leaf N(area) and g(s). During the summer, +H2O and +H2O +N plants displayed higher A(area) than control and +N plants, which was attributed to higher Psi(shoot), g(s) and SLA. Throughout the year, A(area) was strongly correlated with g(s) but weakly correlated with leaf N(area) and SLA. We concluded that increased summer monsoon had a stronger effect on the performance of Larrea than increased N deposition. In the short term, the +H2O and +H2O +N treatments were associated with increasing A(area) in summer, but also with low leaf N(area) and lower A(area) in the long term the following spring.

Patterns of co-morbidity in male suicide completers.

BACKGROUND: Psychiatric co-morbidity is thought to be an important problem in suicide, but it has been little investigated. This study aims to investigate patterns of co-morbidity in a group of male suicide completers. METHOD: One hundred and fifteen male suicide completers from the Greater Montreal Area and 82 matched community controls were assessed using proxy-based diagnostic interviews. Patterns of co-morbidity were investigated using latent class analysis. RESULTS: Three subgroups of male suicide completers were identified (L2 = 171.62, df = 2012, P < 0.05). they differed significantly in the amount of co-morbidity (Kruskal-Wallis chi2 = 71.227, df = 2. P < 0.000) and exhibited different diagnostic profiles. Co-morbidity was particularly found in subjects with disorders characterized by impulsive and impulsive-aggressive traits, whereas subjects without those traits had levels of co-morbidity which were not significantly different from those of controls (chi2 = 8.17, df = 4, P = 0.086). CONCLUSIONS: Suicide completers can be divided into at least three subgroups according to co-morbidity: a low co-morbidity group, a substance-dependent group and a group exhibiting childhood onset of psychopathology.

Suicide and serotonin: study of variation at seven serotonin receptor genes in suicide completers.

Suicide is an important public health problem, accounting for a significant proportion of total mortality among young people, particularly males. There is growing and consistent evidence suggesting that genetic factors play an important role in the predisposition to suicide. Based on several lines of evidence supporting a reduced serotonergic neurotransmission in subjects who committed suicide, we investigated variation at genes that code for serotonin receptor 1B (5-HTR1B), 1Dalpha (5-HTR1Dalpha), 1E (5-HTR1E), 1F (5-HTR1F), 2C (5-HTR2C), 5A (5-HTR5A), and 6 (5-HTR6) in a total sample of 106 suicide completers and 120 normal controls. No differences were observed in allelic or genotypic distributions between groups for any of the loci investigated. Moreover, further analysis according to suicide method or psychopathology also failed to reveal differences between groups. Our results do not support a substantial role of these serotonergic receptors in suicide completion.

Preparation of resin-bound N-(alpha-methoxyalkyl)amides: an advantageous use of solid-phase chemistry for the handling of unstable precursors of the versatile N-acyliminium ions.

The development of a new and efficient synthesis of resin-bound N-(alpha-methoxyalkyl)amides is described. The condensation of aldehydes on a supported amide in the presence of trimethyl orthoformate afforded, in acidic media, the resin-bound N-acyliminium ion precursors. Repeating the reaction a second time led to a great improvement in yields, demonstrating one advantage of the solid-phase chemistry for the handling of sensitive intermediates difficult to isolate.

Are UN peacekeepers at risk for suicide?

Media reports connecting UN peacekeeping duties by Canadian soldiers to their subsequent suicide prompted this study of peacekeeping as suicide risk. In a case-control design we retrospectively compared 66 suicides in the Canadian military between 1990 and 1995 with two control groups: (a) 2,601 controls randomly selected from the electronic military database and (b) 66 matched controls with complete personnel and medical data. We found no increased risk of suicide in peacekeepers except among a subgroup of air force personnel. Here confounding individual factors, isolation from supports, and possibly inadequate preparation for deployment elucidated their suicides. Theater of deployment (e.g., Bosnia) did not affect the suicide rate. Military suicides experienced psychosocial stresses and psychiatric illness more often than their matched controls. We conclude that although peacekeeping per se does not increase overall suicide risk, military life-styles may strain interpersonal relationships, encourage alcohol abuse, and contribute to psychiatric illness and suicide in a minority of vulnerable individuals irrespective of peacekeeping assignment. Careful selection, and preparatory military training that encourages intragroup bonding and mutual support, may protect against suicide risk.

TPH and suicidal behavior: a study in suicide completers.

An association between the gene that codes for tryptophan hydroxylase (TPH)-the rate-limiting enzyme in the synthesis of serotonin-and suicidal behavior has been investigated with some detail in samples of living subjects who attempted suicide. In this study, we investigated TPH and suicide completion, the most severe form of suicidal behavior. A relatively large sample of suicide completers (n = 101) was genotyped at three TPH loci (two polymorphisms in the promoter region, A-6526G and G-5806T, and one in intron 7, A218C) and compared to psychiatrically normal living controls (n = 129). Although no significant differences were found between groups for genetic variation at single loci, haplotype analysis revealed that one haplotype (-6526G -5806T 218C) was significantly more frequent among suicide cases than in normal controls (chi(2) = 11.30, df = 2, P = 0.0008; OR = 2.0 CI: 1.30-3.6). Further analyses suggested that this haplotype is particularly more frequent among subjects who committed suicide using violent methods. Similar results were observed in recent haplotype analyses in suicide attempters, which found that the equivalent of haplotype -6526G -5806T 218C was more frequent in impulsive attempters (Rotondo et al, Mol Psychiatry 1999; 4: 360-368). Our results replicate in suicide completers previous data observed in suicide attempters. These and other results continue to point to the substantial role that the gene that codes for TPH may play in the neurobiology of suicidal behavior.

Equilibrium partition theory applied to PCBs in macrophytes.

The applicability of the equilibrium partition theory (EPT) for PCB accumulation in submerged macrophyte shoots was investigated using field data. The equilibrium state of PCBs between macrophyte shoots and sediments was verified by testing the direct proportionality (slope = 1 in a log-log relationship) between congener concentrations in the lipids of macrophyte shoots (Cli) and in the organic fraction of sediments (Cso), using the slope-range method. A significant proportionality was found between Cli and Cso (slope of the log-log relationship: 0.978 +/- 0.041; R2 = 0.847; P < 0.001). The biota-sediment accumulation factor (BSAF) predicted from this relationship (3.74, SE: 1.14) was in the 1-4 range that is suggested in the literature. These results indicate that, in our study sites, EPT is applicable to PCBs in macrophyte shoots. This opens interesting perspectives in environmental monitoring.

Prediction of level of serotonin 2A receptor binding by serotonin receptor 2A genetic variation in postmortem brain samples from subjects who did or did not commit suicide.

OBJECTIVE: Postmortem studies have indicated that suicide victims have greater serotonin receptor 2A (5-HTR2A) binding in prefrontal brain regions. However, there remains some controversy regarding the biological specificity of these findings. The authors hypothesized that the variance observed in brain 5-HTR2A binding is genetically mediated, at least in part. METHOD: Postmortem data from 56 subjects who had committed suicide and 126 normal comparison subjects were studied; brain tissue was available from 11 subjects who committed suicide and 11 comparison subjects. Homogenate binding assays were carried out with [3H]ketanserin. Variation at the 5-HTR2A gene (HTR2A) was investigated by means of two polymorphisms: T102C and A-1438G. RESULTS: 5-HTR2A binding was greater in the prefrontal cortex of the subjects who committed suicide. In addition, the findings suggest that HTR2A variation significantly affects 5-HTR2A binding. However, no interaction between suicidal behavior and this locus was observed. CONCLUSIONS: These results confirm previous reports of greater 5-HTR2A binding in subjects who committed suicide; they also provide preliminary evidence suggesting that the number of 5-HTR2A receptors is genetically mediated.

The reliability of the community version of the MRC Needs for Care Assessment.

One hundred and nine adults were screened in the community using the abridged version of the CIDI (CIDIS). The subjects comprised DSM-III-R current cases (N = 48), lifetime cases (N = 31) and non-cases (N = 30). The interviews with the 109 subjects were conducted by one of two pairs of clinicians and videotaped. Each interviewer-pair included a psychiatrist and a clinical psychologist. They rated the community version of the Needs for Care (NFCAS-C) by consensus. The other pair of judges then viewed the video and rated the NFCAS-C independently. The agreement on overall needs was excellent (kappa = 0.75), and very good for four of the seven specific sections (from kappa = 0.61 to 0.81). One section could not be rated because of low prevalence, and agreement was less good for the remaining two sections. Agreement was good on specific interventions (medication, kappa = 0.60; specific psychotherapy, kappa = 0.55), but poor on non-specific interventions. The majority of disagreements were due to differences in clinical judgement rather than to technical errors. A new instruction manual has been produced and should help training as well as stabilizing reliability. In devising reliable and valid instruments based on clinical judgement, a balance must be achieved between enhancing reliability with more precise rules and constraining clinical judgement so tightly that validity is lost.

[Exploratory study of the sources of stress and of social support in community and mental health workers]. / Une étude exploratoire des sources de stress et de soutien social chez les intervenantes communautaires en santé mentale.

The objective of this exploratory research is to identify the main sources of work stress and burnout among community mental health workers and examine the social support they receive. Information has been collected through individual and group interviews with 19 community workers from three crisis centres in Montreal. The most stressing factors identified by participants are related to their intervention with users and their roles as intervention worker. Difficulties related specifically to community work are also reported. Social support received from colleagues and quality of relations with superiors stand out as important factors of protection against stress and burnout.

An occupational therapy course on community practice.

This article outlines a course on occupational therapy community practice offered at the University of Ottawa and discusses its assets and limitations in terms of preparing students for the shift to community-based health services. The shift to community services in the health care systems of Ontario and Québec is described. Then the curricular components needed to prepare students for community practice are summarized. Finally, the community practice course at the University of Ottawa including its goal, objectives, class topics and evaluations is outlined. The strength of the community practice course described is that it includes many of the curricular components needed for community practice. On the other hand, limitations include the lack of skill training in some areas, its place in the last year of the programme, and its optional nature. Changes planned for the course and other recommendations for curricula are also discussed.

Suicide and mental disorders: a case-control study of young men.

OBJECTIVE: By means of the psychological autopsy method and a case-control design, the authors examined the association of specific mental disorders and comorbidity with suicide among young men. METHOD: Seventy-five men aged 18-35 years whose deaths were adjudicated as completed suicides by coroners of greater Montreal and Quebec City were matched to 75 living young men for age, neighborhood, marital status, and occupation. For each subject in both groups a key respondent best acquainted with the subject was interviewed by clinicians using standardized schedules. Information from the coroner and medical records was also collected. Two experienced psychiatrists, blind to outcome, established best-estimate DSM-III-R diagnoses. RESULTS: Six-month prevalence rates for all axis I diagnoses for the suicide and comparison groups were 88.0% and 37.3%, respectively; major depression was present in 38.7% and 5.3%, alcohol dependence in 24.0% and 5.3%, psychoactive substance dependence in 22.7% and 2.7%. Borderline personality disorder was identified in 28.0% and 4.0%, respectively. Of the suicide subjects, 28.0% had at least two of the following disorders: major depression, borderline personality disorder, and alcohol or drug dependence; the rate was 0.0% among the comparison subjects. CONCLUSIONS: In young men, completed suicide is linked to specific mental disorders, namely, major depression, borderline personality disorder, and substance abuse. Comorbidity involving any of these disorders is frequently associated with completed suicide.

[Suicide among young male adults in Quebec: psychopathology and utilization of medical services]. / Le suicide chez les jeunes adultes de sexe masculin au Québec: psychopathologie et utilisation des services médicaux.

Seventy five young male adults between the age of 18 and 35 who had committed suicide were compared with 75 male adults still alive matched for age, residence, marital and employment status. For each group a principal respondent was interviewed in order to reconstitute the psychological profile of each individual, as well as their utilisation of health services. This was completed by the study of the coroner's reports and the medical records when available. At six months the prevalence for all axis I diagnosis was 88.8% for the suicide group and 37.3% for the control group. Among the subjects who had committed suicide 38.7% were afflicted by major depression, 24% by alcohol dependency and 28.7% were dependent on drugs. Borderline personalities were present in 28% of the suicide group compared to 5% in the control group. Forty five percent (45%) of the subjects who had killed themselves had consulted a mental health professional in the year preceding the suicide compared to 5% in the control group. However, 78.5% of the suicide group had consulted during the same period a health professional compared to 73.3% of the controls.

The community work project: an occupational therapy programme.

The Community Work Project is a work adjustment programme, part of a range of prevocational services offered in the occupational therapy department of the Royal Ottawa Hospital, in Ottawa, Ontario. The special feature of this work adjustment programme is the use of an integrated work environment. Compared to institutionally-based programmes, this work adjustment programme consists of clients undergoing treatment alongside regular competitive employees in a real work setting. Another important feature of this programme is its open length of stay. The Community Work Project is described, with information on programme need, components, referral process and goals/objectives. Data on sex, age, diagnosis, attendance rates, lengths of stay, graduation placements and client satisfaction are also given. The Community Work Project demonstrates how the use of a productive activity in a real work setting assists individuals with psychiatric disabilities to progress in their vocational rehabilitation process. Implications for the vocational rehabilitation of this population are discussed.

A Canadian model for developing mental health services in rural communities through linkages with urban centers.

The development of mental health care services in rural areas has been a constant challenge in most countries of significant geographical size. By use of a case study from Canada, the development of a relationship between rural and urban mental health services was described. Issues including referral patterns, service accessibility, professional recruitment and the development of service in rural regions were studied. It is advanced that mental health administrators, policy-makers, clinical service coordinators and educators will find that this approach to the development of mental health services in rural areas has some utility in Canada and in other countries.