Adolescents' and providers' perspectives on the need for and use of mental health services

PURPOSE

This study examines need for and use of services from both the adolescent's and the service provider's viewpoints.

METHODS

The Youth Services Project interviewed 792 youths from the juvenile justice, education, primary health care, and child welfare sectors (200 each); gathered anonymous tallies of the mental health of youthful clients at each sector; and conducted focus groups with providers.

RESULTS

A high percentage of youths (12-15%) met DSM-IV criteria for a mental health disorder, yet the sector clients were not identified as having mental health problems. Juvenile justice and child welfare sectors identified the highest percentage of adolescent clients as having mental health problems, and provided the most services (50-80%). The primary health care sector recorded no mental health disorders among the tallied clients, and provided the fewest mental health services (< 20%). Providers' complaints that they lacked knowledge concerning mental health assessment and lacked referral or treatment resources closely paralleled the degree to which their sector underserviced youths.

CONCLUSION

Lack of knowledge about the extent of need in adolescents, methods for assessing or treating, and referral resources handicap service providers and explain the gap between need and service.

The suppressive effect of electrical stimulation on nociceptive responses in the rat

BACKGROUND AND PURPOSE

The aim of this investigation was to study the effect of electrical stimulation on nociceptive responses within the lumbar levels of the rat spinal cord.

METHODS

A single high-energy thermal pulse produced by a surgical laser stimulator (5 W, 30 milliseconds) was applied on the plantar surface of the hind paws of male Sprague-Dawley rats. The spinal cord field potential evoked by the laser pulse was used as an indicator of thermosensitive nociceptive responses. Low-intensity single stimulation, high-intensity single stimulation, low-intensity train stimulation, and high-intensity train stimulation were applied on the common peroneal nerve with protected cuff electrodes in different trials.

RESULTS

Neither low-intensity nor high-intensity single stimulation suppressed field potentials. In contrast, low-intensity train stimulation elicited partial inhibition of field potentials. Furthermore, high-intensity train stimulation elicited biphasic inhibition at a wider range of intervals lasting for 20 seconds.

CONCLUSION AND DISCUSSION

The results demonstrate that two modes of train electrical stimulation can produce two patterns of fast-onset (within milliseconds), short-duration (within 20 seconds) inhibition of field potentials in the spinal cord. These results provide evidence that noxious heat-related impulses are modulated by the presence of specific electrical stimulation. The clinical application of transcutaneous electrical nerve stimulation to block pain is supported.

A comparison of the clock drawing test and the Pfeiffer Short Portable Mental Status Questionnaire in a geropsychiatry clinic

Wolf-Klein and colleagues' clock drawing test (CDT) performance was compared with Pfeiffer's Short Portable Mental Status Questionnaire (Pfeiffer) scores in 145 outpatient geropsychiatry patients. Although normal CDT results were almost always associated with normal Pfeiffer scores, 21% of Pfeiffer normal individuals drew abnormal clocks. Age, but not gender or education, was significantly associated with this finding. Almost all the Pfeiffer normal subjects who drew abnormal clocks were diagnosed with primary psychiatric disorders (85%) or neurologically based organic mood and anxiety disorders (12%); only one (3%) had dementia. We suggest the discrepant performance between the CDT and Pfeiffer may result from psychiatric illness. Contributing to this may be CDT sensitivity to executive skills dysfunction. This dyscontrol can occur in patients with dementia and other neurological disorders, but also presents in some primary mental disorders. Older age may heighten this impairment. In a typical geropsychiatry clinic, the CDT will not have high specificity for Alzheimer's disease as reported by Wolf-Klein and her colleagues. This results from the presence of many patients with primary psychopathology, some of whom will draw abnormal clocks, and a limited number with dementia-particularly Alzheimer's disease. Abnormal CDT results of geropsychiatry outpatients must therefore be interpreted carefully. Additional conclusions regarding the study results are discussed.

A comparison of the effects of different degrees of zona pellucida damage followed by cryopreservation on the postthaw development of mouse embryos

PURPOSE

The totally intact zona pellucida is not essential for the development of embryos. It is still unclear how much effect the degree of damages to the zona pellucida will have on the developmental potential of postthaw embryos after cryopreservation. We compared the developmental potential of cryopreserved mouse embryos after induction of two degrees of mechanical damage to the zonae pellucidae by micromanipulation.

METHODS

In experiment I, the development of 124 cryopreserved ICR mouse embryos to the blastocyst stage after zona pellucida penetration of two-cell embryos as in the procedures of subzonal sperm insertion (SUZI) was compared with the development of zona-intact cryopreserved embryos. In experiment II, the zonae pellucidae of 93 two-cell mouse embryos were dissected as in the procedures of partial zonal dissection (PZD), following which the embryos were frozen. This postthaw development was also compared with that of zona-intact two-cell cryopreserved embryos. All the embryos were thawed and cultured to the blastocyst stage. Additional controls were provided by culturing zona-intact and zona-penetrated or zona-dissected embryos without cryopreservation.

RESULTS

The development of unfrozen mouse embryos was not affected by either zona penetration (P = 0.433) or zona dissection (P = 0.659). The developmental potential of cryopreserved mouse embryos was significantly affected after zona dissection (blastocyst rate, 31% ZD vs 72%, control; P < 0.001) but not after zona penetration (blastocyst rate, 59% ZP vs 64% control; P = 0.441).

CONCLUSIONS

The quality of cryopreserved embryos was affected by a large hole on the zona pellucida created by zona dissection but not by simple zona penetration.

Reverse jugular flow in a case of thrombosis of the brachiocephalic vein with an artificial arteriovenous fistula

Thrombosis of the thoracic inlet veins following placement of a central venous catheter is a well-known complication, and several findings have been reported by color Doppler sonography. However, reverse jugular flow resulting from this complication is rarely mentioned and should be differentiated from another complication of iatrogenic arteriovenous fistula between neck vessels. The authors here describe a uremic patient with an artificial arteriovenous fistula in the forearm complicated with thrombosis of the ipsilateral brachiocephalic vein. Factors permitting the differential diagnosis by coloer Doppler sonography and clinical conditions are proposed.

Cpk is a novel class of Drosophila PtdIns 3-kinase containing a C2 domain

We report the identification of a novel class of phosphatidylinositol (PtdIns) 3-kinases whose members contain C-terminal C2 domains. We have isolated Drosophila and murine genes (termed cpk and cpk-m respectively) by polymerase chain reaction amplification of cDNA libraries with degenerate primers corresponding to conserved regions of PtdIns kinases. The amino acid sequences of Cpk and Cpk-m are most similar to that of p110, a family of PtdIns 3-kinases that mediates the responses of cells to mitogenic stimuli. The Cpk and Cpk-m sequences are similar to a large, central region of p110, but differ from p110 at their N and C termini. The N termini of the Cpk proteins do not contain any recognizable protein motif, while the C termini contain "C2 domains," a feature unique among PtdIns kinases. Cpk has an intrinsic PtdIns kinase activity and can phosphorylate PtdIns and PtdIns-4-P, but not PtdIns(4,5)P2, at the D3 position of the inositol ring. Cpk is the first PtdIns 3-kinase identified with this particular substrate specificity. We have identified two potential Cpk-binding proteins, p90 and p190, and have determined that both Cpk and p190 may be tyrosine phosphorylated. This finding suggests that Cpk function may be regulated by tyrosine kinases.

Retest stability of DSM-III-R diagnoses among adolescents using the Diagnostic Interview Schedule for Children (DISC-2.1C)

Retest stability of DSM-III-R diagnoses was assessed using the DISC-2.1C with a sample of Anglo, African, and Hispanic American adolescent patients 12 to 17 years of age. Based on the kappa statistic, retest stability was fair for any disorder (kappa = .50), for any anxiety disorder (kappa = .44), for any affective disorder (kappa = .53), for any disruptive behavior disorder (kappa = .58), and for substance use disorders (kappa = .46). Although there was a trend for reliability to be somewhat higher for African Americans (kappa = .58) than for Anglos (kappa = .42) or Hispanics (kappa = .49), these differences were not statistically significant. In general, 15- to 17-year-olds had somewhat better reliability (kappa = .58) than did 12- to 14-year-olds (kappa = .44). Males had somewhat higher reliability (kappa = .63) than females (kappa = .43). These findings are congruent with those reported recently using the DISC-R (Schwab-Stone et al., 1993) and suggest that the DISC appears to be at least as reliable as other available child diagnostic instruments. In view of the fair-to-moderate levels of reliability of these instruments in general, future research should focus on the joint effects of instrument, subject, interviewer, and nomenclature on operating characteristics of diagnostic interview schedules, focusing in particular on factors affecting accurate recall and reporting of symptoms and episodes.

Lifetime rates of suicide attempts among subjects with bipolar and unipolar disorders relative to subjects with other Axis I disorders

The lifetime rate of suicide attempts among subjects in the Epidemiologic Catchment Area database with bipolar disorder, unipolar disorder, and any other DSM-III-defined Axis I disorder were determined. The latter constituted a control or reference group. The lifetime rates of suicide attempts of persons in these diagnostic groups were 29.2%, 15.9%, and 4.2%, respectively. Multivariate logistic regression analysis was used to calculate the odds ratio of subjects within a diagnostic group having a history of a suicide attempt relative to subjects in a second group. The odds ratio of subjects with bipolar disorder having a history of a suicide attempt relative to subjects in the control group was 6.2 (df 1, x(2) = 5347.2, p < .0001). The odds ratio of subjects with unipolar disorder having a history of a suicide attempt relative to subjects in the control group was 3.1 (df = 1, x(2) = 4785.2, p < .0001). The odds ratio of subjects with bipolar disorder having a history of a suicide attempt relative to unipolar subjects was 2.0 (df = 1, x(2) = 697.9, p < .0001). Bipolar disorder has a strong relationship to a history of suicide attempts relative to unipolar disorder and other Axis I disorders.

Ras-interacting domain of RGL blocks Ras-dependent signal transduction in Xenopus oocytes

RalGDS family members (ralGDS and RGL) interact with the GTP-bound form of Ras through its effector loop. The C-terminal region (amino acids 602-768) of RGL is responsible for binding to Ras. In this paper we characterized a Ras-interacting domain of RGL using deletion mutants of RGL(602-768). RGL(602-768), RGL(632-768), and RGL (602-734) bound to the GTP-bound form of Ras and inhibited the GAP activity of NF-1. RGL(646-768) showed a low binding activity to Ras and inhibited GAP activity of NF-1 weakly. None of RGL(659-768), RGL(685-768), RGL(602-709), and RGL(602-686) bound to Ras or inhibited GAP activity of NF-1. These results indicate that amino acids 632-734 of RGL constitute a nearly minimal domain that contains the binding element for Ras. RGL(632-734) inhibited v-Ras- but not progesterone-induced Xenopus oocyte maturation. Furthermore, RGL(632-734) inhibited v-Ras- but not v-Raf- dependent extracellular signal-regulated kinase activation in Xenopus oocytes. These results clearly demonstrate that the Ras-interacting domain of RGL is important for Ras-dependent signal transduction in vivo.

Diagnosis and follow-up of carotid-cavernous fistulas by carotid duplex sonography and transcranial color Doppler imaging

To investigate the suitability of extracranial carotid duplex (ECD) and transcranial color Doppler imaging (TCDI) in the diagnosis and follow-up of treatment in patients with carotid-cavernous fistulas (CCF), combined ECD and TCDI examinations were studied in seven patients with traumatic CCF. According to angiography, four patients had direct CCF, two indirect CCF and one both direct and indirect CCF. In ECD, hemodynamic parameters of the feeding artery showed an abnormally increased flow volume and decreased resistivity indices in five direct CCFs from the internal carotid artery and one indirect CCF from the external carotid artery. Direct visualization of the CCF was achieved in patients with direct CCF only, and revealed itself as a heterogeneous mosaic flash resulting from high flow velocities and turbulence. Patterns of venous drainage were detected via the transorbital and transforaminal windows in seven and five patients (four direct and one indirect CCF patients), respectively. These abnormal findings were improved or even normalized after successful treatment. In conclusion, combined ECD and TCDI examinations appear to be useful for the diagnosis and follow-up of CCF.

Symptoms of DSM-III-R major depression among Anglo, African and Mexican American adolescents

Ethnocultural differences in the phenomenology of DSM-III-R major depression among adolescents was examined in a sample of 334 Anglo, African and Mexican American patients 12-17 years of age. Diagnoses were made using the Diagnostic Interview Schedule for Children, Version 2.1. Analyses of rates of individual symptoms as well as the nine DSM-III-R criteria revealed minimal differences among youths in the three ethnic groups who received a diagnosis of major depressive disorder. There also were minimal differences between boys and girls in symptom profiles.

Functional analysis of E. coli threonine dehydrogenase by means of mutant isolation and characterization

The oxidation of L-threonine to 2-amino-ketobutyrate, as catalyzed by L-threonine dehydrogenase, is the first step in the major pathway for threonine catabolism in both eukaryotes and prokaryotes. Threonine dehydrogenase of E. coli has considerable amino-acid sequence homology with a number of Zn(2+)-containing, medium-chain alcohol dehydrogenases. In order to further explore structure/function interrelationships of E. coli threonine dehydrogenase, 35 alleles of tdh that imparted a no-growth or slow-growth phenotype on appropriate indicator media were isolated after mutagenesis with hydroxylamine. Within this collection, 14 mutants had single amino-acid changes that were divided into 4 groups: (a) amino-acid changes associated with proposed ligands to Zn2+; (b) a substitution of one of several conserved glycine residues; (c) mutations at the substrate or coenzyme binding site; (d) alterations that resulted in a change of charge near the active site. These findings uncover previously unidentified amino-acid residues that are important for threonine dehydrogenase catalysis and also indicate that the three-dimensional structure of tetrameric E. coli threonine dehydrogenase has considerable similarity with the dimeric horse liver alcohol dehydrogenase.

Risk factors for clozapine discontinuation among 805 patients in the VA hospital system

The goal of this study was to determine if demographic or clinical factors collected at baseline on patients treated with clozapine would increase the risk of having clozapine discontinued for (a) lack of response, (b) side effects, (c) noncompliance, (d) concomitant illness, or (e) death. The subjects were 805 patients treated with clozapine at 96 Department of Veterans Affairs Hospital System facilities. Multiple logistic regression was used to determine if any of the baseline variables predisposed patients to discontinuation from treatment. Factors which were studied include age, race, history of inadequate response to traditional neuroleptics, history of substance abuse, and DSM-III-R Axis I diagnosis. Of the 805 patients started on clozapine 167 (20.7%) were discontinued from treatment. The only significant variable in the logistic regression model was race. This study finds that African American patients are more likely to have clozapine discontinued than non-African American patients, and there is a trend for prior history of inadequate response to traditional neuroleptics to predict clozapine discontinuation. We found no effect of substance abuse or dependence, diagnosis, or age on outcome in the overall patient group. In a post hoc analysis the African American patients had a significantly lower baseline white blood count than the non-African American patients, which could have explained the difference in clozapine discontinuation. The findings of this study support further investigation into the causes of ethnic differences in treatment outcome with clozapine.

Comorbidity for obsessive-compulsive disorder in bipolar and unipolar disorders

The lifetime rates of obsessive-compulsive disorder (OCD) among subjects with histories of (1) bipolar disorder, (2) major depressive disorder but not of hypomania or mania (unipolar disorder), and (3) any Axis I disorder defined in DSM-III other than bipolar or unipolar disorders (i.e., 'other' disorder) was determined using the Epidemiologic Catchment Area (ECA) data base. The strengths of the relationships between OCD and diagnostic group, as well as between OCD and suicidality, were assessed in a multivariate logistic regression analysis. The lifetime rates of OCD among subjects with bipolar, unipolar and other Axis I disorder are 21.0, 12.2, and 5.9%, respectively. The odds ratios of subjects with bipolar and unipolar disorders meeting the criteria for OCD relative to subjects with any other Axis I disorder are 3.2 and 1.6, respectively. The odds ratio of subjects with bipolar disorder meeting the criteria for OCD relative to subjects with unipolar disorder is 2.0. The rates of panic disorder among subjects with bipolar disorder who do and do not meet the criteria for OCD are 37.1 and 16.7%, respectively. The ECA data base supports the conclusion that the lifetime rate of comorbidity for OCD is particularly high among bipolar subjects. OCD may be associated with panic disorder. These data highlight the potential value of clinical study of comorbidity for OCD in bipolar illness.

Aging in adults with Down syndrome: report from a longitudinal study

Changes in functioning related to aging were examined in 34 adults (14 females, 20 males) with Down syndrome who were 22 to 56 years of age. Changes in functioning over 3 to 4 years were examined, with age, IQ at entry into the study, and gender considered. Neither effects of age at entry nor change over time were significant, suggesting that changes related to aging in adults with Down syndrome were minimal. In contrast, IQ at entry had a significant effect on all performances, suggesting that any examination of aging must consider intellectual level. Results do not support the idea that adults with Down syndrome show rapid age-related declines in functioning apart from the occurrence of a progressive dementia such as Alzheimer's disease.

Unified Neurological Stroke Scale is valid in ischemic and hemorrhagic stroke

BACKGROUND AND PURPOSE

The growing interest in testing new therapeutic agents for acute brain injury has lead to increased use of stroke scales. The reliability and validity of these measures need to be examined more completely. We used structural equation modeling, a technique that merges the analytic procedures of factor analysis and multiple regression, to examine the reliability and construct validity of the Middle Cerebral Artery Neurological Scale and the Scandinavian Neurological Stroke Scale used together as the Unified Neurological Stroke Scale. We also analyzed the predictive validity, sensitivity, and specificity of the scales in predicting mortality and functional outcome.

METHODS

We prospectively studied 84 consecutive patients admitted to a neurology/neurosurgery intensive care unit with intracerebral hemorrhage (n = 30), subarachnoid hemorrhage (n = 15), ischemic stroke (n = 15), and traumatic brain injury (n = 24). Patients were evaluated within 24 hours of admission and at 48-hour intervals until intensive care unit discharge. A total of 386 assessments were obtained. The Functional Independence Measure was administered by telephone 3 months after hospital discharge.

RESULTS

High levels of reliability and construct validity were observed for the majority of the Unified Stroke Scale items. Facial palsy and eye movement items had the lowest reliability and validity. Both the Middle Cerebral Artery and Scandinavian Scales were significant predictors of outcome. Sensitivity and specificity varied by diagnosis. Predictive validity of functional outcome was best in groups with ischemic and hemorrhagic stroke rather than traumatic brain injury and subarachnoid hemorrhage.

CONCLUSIONS

The Unified Stroke Scale demonstrates reliability and construct and predictive validity, and its use is supported in ischemic and hemorrhagic stroke. Structural equation modeling is an appropriate technique for use with scales of this type.

Characterization of irreversible binding of beta-funaltrexamine to the cloned rat mu opioid receptor

Binding of beta-funaltrexamine (beta-FNA) to the cloned rat mu opioid receptor expressed in COS-1 cells or Chinese hamster ovary cells was examined. beta-FNA bound to the mu receptor with high affinity. Irreversible binding of [3H]beta-FNA was defined as the binding that could not be dissociated by trichloroacetic acid. Na+ greatly enhanced the specific irreversible binding of [3H]beta-FNA to the mu receptor, which was concentration- and time-dependent. Specific irreversible binding of [3H]beta-FNA was potently inhibited by CTAP (a mu ligand), but not by ICI174,864 (a delta ligand) or U50,488H (a kappa ligand). These results indicate that [3H]beta-FNA binds irreversibly to the cloned mu opioid receptor. SDS-polyacrylamide gel electrophoresis and fluorography showed that [3H]beta-FNA-labeled receptors migrated as one broad and diffuse band with a mass of 80 kDa in Chinese hamster ovary or COS cells and as one band with a mass of 67 kDa in the rat brain preparation. Upon removal of N-linked carbohydrates, labeled receptors became a sharper band with a mass of approximately 40 kDa. [3H]beta-FNA did not bind irreversibly to the cloned rat kappa receptor. [3H]beta-FNA binding to four chimeric mu/kappa receptors was examined. The region from the middle of the third intracellular loop to the C terminus of the mu receptor is necessary for irreversible binding of beta-FNA.

Comorbidity of panic disorder in bipolar illness: evidence from the Epidemiologic Catchment Area Survey

OBJECTIVE

The authors' goal was to determine the rate of comorbid panic disorder in individuals with bipolar disorder.

METHOD

They used the Epidemiologic Catchment Area survey database to determine the prevalence of comorbid panic disorder in individuals with unipolar depression, those with bipolar disorder, and comparison subjects without bipolar or unipolar disorder.

RESULTS

The lifetime prevalence of panic disorder among subjects with bipolar disorder was 20.8%; among subjects with unipolar depression it was 10.0%, and among comparison subjects it was 0.8%.

CONCLUSIONS

Individuals with bipolar disorder have a particularly high risk of comorbid panic disorder. The evaluation of patients with bipolar disorder should include screening for panic disorder.

Depressive symptoms and suicidal ideation among Mexican-origin and Anglo adolescents

OBJECTIVE

To examine the prevalence of depressive symptoms and suicidal ideation, their comorbidity, and associated risk factors in adolescence.

METHOD

A self-administered questionnaire was completed in class by students in three middle schools (grades 6 through 8) enrolling more than 3,200 students. Usable questionnaires were obtained from 2,614 (81.5%), of which 924 were Anglo and 1,354 were of Mexican origin Depression was measured using the 20-item Center for Epidemiologic Studies Depression Scale and suicidal ideation using four items on thoughts of death and suicide.

RESULTS

The minority adolescents reported significantly higher crude prevalence rates of symptoms of depression and thoughts of suicide than their Anglo counterparts. Prevalence rates were highest for females of Mexican origin. There was a strong association between depression and suicidal ideation in both ethnic groups. Multivariate logistic regression analyses indicated significant correlates of depressive symptoms were suicidal ideation (adjusted odds ratio = 10.9), loneliness, and use of English, in that order. Significant correlates of suicidal ideation were depression (adjusted odds ratio = 10.6), loneliness, two-parent household, use of English, and being of Mexican origin. More than 80% of those with high ratings on suicidal ideation scored as depressed in both ethnic groups.

CONCLUSIONS

Results are consistent with other studies suggesting rates of suicidal ideation among adolescents are in the 10% to 20% range, while rates of depressive symptoms are in the 35% to 50% range using standard caseness scores. Mexican-American youths appear to be at higher risk than Anglo youths, particularly for suicidal ideation. In addition, it appears that youths who are lonely are more likely to report higher rates of both depression and suicidal ideation. The data also indicate that youths who spoke only or mostly English reported lower rates of depression and suicidal ideation, suggesting that acculturation may play a role as well.

ralGDS family members interact with the effector loop of ras p21

Using a yeast two-hybrid system, we identified a novel protein which interacts with ras p21. This protein shares 69% amino acid homology with ral guanine nucleotide dissociation stimulator (ralGDS), a GDP/GTP exchange protein for ral p24. We designated this protein RGL, for ralGDS-like. Using the yeast two-hybrid system, we found that an effector loop mutant of ras p21 was defective in interacting with the ras p21-interacting domain of RGL, suggesting that this domain binds to ras p21 through the effector loop of ras p21. Since ralGDS contained a region highly homologous with the ras p21-interacting domain of RGL, we examined whether ralGDS could interact with ras p21. In the yeast two-hybrid system, ralGDS failed to interact with an effector loop mutant of ras p21. In insect cells, ralGDS made a complex with v-ras p21 but not with a dominant negative mutant of ras p21. ralGDS interacted with the GTP-bound form of ras p21 but not with the GDP-bound form in vitro. ralGDS inhibited both the GTPase-activating activity of the neurofibromatosis gene product (NF1) for ras p21 and the interaction of Raf with ras p21 in vitro. These results demonstrate that ralGDS specifically interacts with the active form of ras p21 and that ralGDS can compete with NF1 and Raf for binding to the effector loop of ras p21. Therefore, ralGDS family members may be effector proteins of ras p21 or may inhibit interactions between ras p21 and its effectors.

Suicidality in patients with pure and depressive mania

OBJECTIVE

A previous comprehensive literature review indicated that suicide accounted for 18.9% of the deaths of 9,389 individuals with manic-depressive illness. The literature associates these deaths with the depressed phase of the disease. This study was designed to determine the rate and severity of suicidality among patients with pure and depressive mania.

METHOD

The patients were 93 persons who met the Research Diagnostic Criteria (RDC) for bipolar I disorder (N = 75) or schizoaffective disorder (N = 18). All met the RDC for primary mania and the DSM-III-R criteria for bipolar disorder, manic or mixed. Patients with depressive mania met the RDC for mania and major depressive disorder concurrently. Severity of current suicidality was measured by using the Schedule for Affective Disorders and Schizophrenia suicide subscale. Differences in the mean suicidality scores between any two groups were assessed with the Kruskal-Wallis test. Relationships of age, gender, type of affective illness (bipolar I versus schizoaffective disorder), psychosis, race, and mania subtype to suicidality were assessed by using multivariate logistic regression analysis.

RESULTS

One (2.0%) of the 49 patients with pure mania was suicidal. In contrast, 24 (54.5%) of the 44 patients with depressive mania were suicidal. This difference was highly significant. Gender and psychosis were not related to suicidality. African-Americans were less likely to be suicidal than Caucasians. Subtype of mania had the strongest relationship to suicidality.

CONCLUSIONS

A subgroup of manic patients are severely suicidal. Presentation in the manic state is an indication for careful assessment of depressive symptoms and suicidality.

Effects of sodium butyrate on the transfer of arachidonic acid to phosphatidylcholine in a clonal oligodendrocyte cell line (CB-II)

The effect of sodium butyrate on membrane phospholipid metabolism in a neonate rat cerebellum derived clonal oligodendrocyte cell line (CB-II) was investigated. Sodium butyrate is an agent known to induce cell differentiation and morphological transformations. A comparison of the in vivo phospholipid labeling patterns obtained by incubating CB-II cells with [3H]choline, [14C]myristic acid or [3H]arachidonic acid indicated that butyrate altered the route of acylation-deacylation in phosphatidylcholine (PC) biosynthesis. Using an in vitro incubation system containing homogenates of CB-II cells, the largest proportion of radioactivity was found in PC, and addition of sodium butyrate resulted in a further increase in the transfer of arachidonic acid to PC, but not to phosphatidylinositol. Similar results were obtained when this in vitro acylation activity was tested using homogenates from sodium butyrate pretreated cells. The butyrate effect was observed regardless of whether or not exogenous lysophosphatidylcholine (LPC) was added to the incubation system. Addition of butyrate did not result in a change in the activity of LPC:acyl-CoA (coenzyme A) acyltransferase (EC 2.3.1.23) in CB-II cells upon incubating cell homogenates with [1-14C]arachidonoyl-CoA and LPC. However, when cell homogenates were incubated with [3H]arachidonic acid in the presence of 2.5-10 mM sodium butyrate, arachidonoyl-CoA synthesis was stimulated. A time course study demonstrated that significant stimulation occurred after three minutes. Taken together, the results suggest that in CB-II cells, sodium butyrate stimulates the transfer of arachidonic acid into PC and that this effect is at least partially due to a stimulation of arachidonoyl-CoA ligase (EC 6.2.1.3).

Stability and solvation of Thr/Ser to Ala and Gly mutations at the N-cap of alpha-helices

The solvation of polar groups at the N-terminal end of alpha-helices was studied by comparing the crystal structures of T4 lysozyme, barley chymotrypsin inhibitor 2 (CI2), barnase and their respective N-cap mutants. Whether or not the N3 residue is solvated on mutating the N-cap Thr/Ser to Ala or Gly appears to be related to the identities and the side-chain conformations of the N2 and N3 residues. When these two residues are alanines, as is in the pseudo-wild-type CI2 (E33A/E34A), the main-chain NH at the N3 position is exposed to the solvent and can be solvated. If the N2 residue is an Asp or a Glu, it is more likely that the side-chain of these residues will form a surrogate N-cap with the amide NH at N3 to compensate for the lost -OH group. In this case, no additional solvation will be observed. In general, Gly can be more stable than Ala at the N-cap because its small side-chain allows nearby polar groups to form hydrogen bonds with optimal geometry with solvent molecules or other polar groups.