The Biomolecular Interaction Network Database and related tools 2005 update

The Biomolecular Interaction Network Database (BIND) (http://bind.ca) archives biomolecular interaction, reaction, complex and pathway information. Our aim is to curate the details about molecular interactions that arise from published experimental research and to provide this information, as well as tools to enable data analysis, freely to researchers worldwide. BIND data are curated into a comprehensive machine-readable archive of computable information and provides users with methods to discover interactions and molecular mechanisms. BIND has worked to develop new methods for visualization that amplify the underlying annotation of genes and proteins to facilitate the study of molecular interaction networks. BIND has maintained an open database policy since its inception in 1999. Data growth has proceeded at a tremendous rate, approaching over 100 000 records. New services provided include a new BIND Query and Submission interface, a Standard Object Access Protocol service and the Small Molecule Interaction Database (http://smid.blueprint.org) that allows users to determine probable small molecule binding sites of new sequences and examine conserved binding residues.

Mice devoid of gamma-aminobutyrate type A receptor beta3 subunit have epilepsy, cleft palate, and hypersensitive behavior

gamma-Aminobutyric acid type A receptors (GABA(A)-Rs) mediate the bulk of rapid inhibitory synaptic transmission in the central nervous system. The beta3 subunit is an essential component of the GABA(A)-R in many brain regions, especially during development, and is implicated in several pathophysiologic processes. We examined mice harboring a beta3 gene inactivated by gene targeting. GABA(A)-R density is approximately halved in brain of beta3-deficient mice, and GABA(A)-R function is severely impaired. Most beta3-deficient mice die as neonates; some neonatal mortality, but not all, is accompanied by cleft palate. beta3-deficient mice that survive are runted until weaning but achieve normal body size by adulthood, although with reduced life span. These mice are fertile but mothers fail to nurture offspring. Brain morphology is grossly normal, but a number of behaviors are abnormal, consistent with the widespread location of the beta3 subunit. The mice are very hyperactive and hyperresponsive to human contact and other sensory stimuli, and often run continuously in tight circles. When held by the tail, they hold all paws in like a ball, which is frequently a sign of neurological impairment. They have difficulty swimming, walking on grids, and fall off platforms and rotarods, although they do not have a jerky gait. beta3-deficient mice display frequent myoclonus and occasional epileptic seizures, documented by electroencephalographic recording. Hyperactivity, lack of coordination, and seizures are consistent with reduced presynaptic inhibition in spinal cord and impaired inhibition in higher cortical centers and/or pleiotropic developmental defects.

Gene knockout of the alpha6 subunit of the gamma-aminobutyric acid type A receptor: lack of effect on responses to ethanol, pentobarbital, and general anesthetics

The alpha6 subunit of the gamma-aminobutyric acid type A receptor (GABA(A)-R) has been implicated in mediating the intoxicating effects of ethanol and the motor ataxic effects of general anesthetics. To test this hypothesis, we used gene targeting in embryonic stem cells to create mice lacking a functional alpha6 gene. Homozygous mice are viable and fertile and have grossly normal cerebellar cytoarchitecture. Northern blot and reverse transcriptase-polymerase chain reaction analyses demonstrated that the targeting event disrupted production of functional alpha6 mRNA. Autoradiography of histological sections of adult brains demonstrated that diazepam-insensitive binding of [3H]Ro15-4513 to the cerebellar granule cell layer of wild-type mice was completely absent in homozygous mice. Cerebellar GABA(A)-R density was unchanged in the mutant mice; however, the apparent affinity for muscimol was markedly reduced. Sleep time response to injection of ethanol after pretreatment with vehicle or Ro15-4513 did not differ between genotypes. Sleep time response to injection of pentobarbital and loss of righting reflex and response to tail clamp stimulus in mice anesthetized with volatile anesthetics also did not differ between genotypes. Thus, the alpha6 subunit of the GABA(A)-R is not required for normal development, viability, and fertility and does not seem to be a critical or unique component of the neuronal pathway mediating the hypnotic effect of ethanol and its antagonism by Ro15-4513 in mice. Similarly, the alpha6 subunit does not seem to be involved in the behavioral responses to general anesthetics or pentobarbital.

Resistance training is accompanied by increases in hip strength and changes in lower extremity biomechanics during running

BACKGROUND

Movement and muscle activity of the hip have been shown to affect movement of the lower extremity, and been related to injury. The purpose of this study was to determine if increased hip strength affects lower extremity mechanics during running.

METHODS

Within subject, repeated measures design. Fifteen healthy women volunteered. Hip abduction and external rotation strength were measured using a hand-held dynamometer. Three-dimensional biomechanical data of the lower extremity were collected during running using a high-speed motion capture system. Measurements were made before, at the mid-point, and after a 6-week strengthening program using closed-chain hip rotation exercises. Joint range of motion (rearfoot eversion, knee abduction, hip adduction, and internal rotation), eversion velocity, eversion angle at heel strike, and peak joint moments (rearfoot inversion, knee abduction, hip abduction, and external rotation) were analyzed using repeated measures analysis of variance (P <or= 0.05). The independent variable was time (pre-, week 3, and week 6). A separate analysis of variance was conducted with the dependent variables of peak hip abduction and external rotation strength.

FINDINGS

Hip abduction (P=0.009) and external rotation strength (P<0.0005) increased by 13% and 23%, respectively. Eversion range of motion decreased (P=0.05), hip adduction range of motion increased (P=0.05), and a trend of decreased hip internal rotation range of motion (P=0.08) were found. Rearfoot inversion moment (P=0.02) and knee abduction moment (P=0.05) decreased by 57% and 10%, respectively.

INTERPRETATION

The hip abductors and external rotators were strengthened, leading to an alteration of lower extremity joint loading which may reduce injury risk. These exercises could be used in the rehabilitation, or prevention, of lower extremity injuries.

Glycine and a glycine dehydrogenase (GLDC) SNP as citalopram/escitalopram response biomarkers in depression: pharmacometabolomics-informed pharmacogenomics

Major depressive disorder (MDD) is a common psychiatric disease. Selective serotonin reuptake inhibitors (SSRIs) are an important class of drugs used in the treatment of MDD. However, many patients do not respond adequately to SSRI therapy. We used a pharmacometabolomics-informed pharmacogenomic research strategy to identify citalopram/escitalopram treatment outcome biomarkers. Metabolomic assay of plasma samples from 20 escitalopram remitters and 20 nonremitters showed that glycine was negatively associated with treatment outcome (P = 0.0054). This observation was pursued by genotyping tag single-nucleotide polymorphisms (SNPs) for genes encoding glycine synthesis and degradation enzymes, using 529 DNA samples from SSRI-treated MDD patients. The rs10975641 SNP in the glycine dehydrogenase (GLDC) gene was associated with treatment outcome phenotypes. Genotyping for rs10975641 was carried out in 1,245 MDD patients in the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study, and its presence was significant (P = 0.02) in DNA taken from these patients. These results highlight a possible role for glycine in SSRI response and illustrate the use of pharmacometabolomics to "inform" pharmacogenomics.

Differences in lower extremity kinematics between a bilateral drop-vertical jump and a single-leg step-down

STUDY DESIGN

Mixed-model, repeated-measures design in a laboratory setting.

OBJECTIVES

To examine the differences in hip, knee, and ankle kinematics between a bilateral drop-vertical jump and single-leg step-down. A secondary purpose was to examine gender differences in kinematics of the tasks.

BACKGROUND

Both a drop-vertical jump and step-down task have been used to evaluate lower extremity movement and injury risk. The differences in joint angles between these tasks have not been reported.

METHODS AND MEASURES

Three-dimensional joint angles of the hip, knee, and ankle of 19 females and 18 males were evaluated with a high-speed camera system while the subjects performed a bilateral drop-vertical jump and a single-leg step-down. Maximum joint angles were compared between tasks and genders using ANOVA models. eversion (12 degrees compared to 8 degrees) (P<.0005) and hip adduction (16 degrees compared to 1 degrees) (P= .03) than the drop-vertical jump. Females had greater hip internal rotation in the step-down than in the drop-vertical jump (5 degrees compared to 2 degrees) (P = .02). When averaged across both tasks, females had greater knee abduction than males in both tasks (4 degrees compared to 0 degrees) (P<.0005).

CONCLUSIONS

The unilateral step-down task produced greater motion in the frontal and transverse planes at the ankle and hip, and would be appropriate in evaluating control of the hip. The bilateral drop-vertical jump produced greater knee abduction in both genders and may be appropriate for evaluating excessive knee abduction as a risk factor for noncontact anterior cruciate ligament injury, for example. The 2 tasks appear to challenge the neuromuscular system in different manners, and both should continue to be used in the investigation of injury risk.

Life events, familial stress, and coping in the developmental course of schizophrenia

Recent studies have isolated some socioenvironmental factors that seem to predict the onset of schizophrenic episodes in vulnerable persons. In particular, stressful life events have been found to cluster in the 3- to 4- week period preceding a schizophrenic episode in some patients. Many persons with a schizophrenic disorder also seem to contribute to additional stressful life change events--for example, by high geographic mobility--thereby playing an active role in precipitating the onset of illness episodes. Within the family environment, hostile, critical, and emotionally overinvolved attitudes toward the patient by relatives have been found to be related to relapses. Irregularities in the communication style of parents also predict the subsequent development of schizophrenia spectrum disorders among disturbed adolescents. Many schizophrenic patients also seem to be deficient in the coping skills required to remediate the losses brought on by life events or to deal effectively with stressful relatives. Thus, they may experience greater and more prolonged stress than most others due partially to inadequate social and problem-solving skills and less supportive social networks. These findings have important implications for the design of clinical interventions as well as the development of a comprehensive vulnerability/stress model for the course of schizophrenic disorders.

Matrix metalloproteinase inhibitor prevents acute lung injury after cardiopulmonary bypass

BACKGROUND

Acute lung injury (ALI) after cardiopulmonary bypass (CPB) results from sequential priming and activation of neutrophils. Activated neutrophils release neutral serine, elastase, and matrix metalloproteinases (MMPs) and oxygen radical species, which damage alveolar-capillary basement membranes and the extracellular matrix, resulting in an ALI clinically defined as adult respiratory distress syndrome (ARDS). We hypothesized that treatment with a potent MMP and elastase inhibitor, a chemically modified tetracycline (CMT-3), would prevent ALI in our sequential insult model of ALI after CPB.

METHODS AND RESULTS

Anesthetized Yorkshire pigs were randomized to 1 of 5 groups: control (n=3); CPB (n=5), femoral-femoral hypothermic bypass for 1 hour; LPS (n=7), sham bypass followed by infusion of low-dose Escherichia coli lipopolysaccharide (LPS; 1 microgram/kg); CPB+LPS (n=6), both insults; and CPB+LPS+CMT-3 (n=5), both insults plus intravenous CMT-3 dosed to obtain a 25-micromol/L blood concentration. CPB+LPS caused severe lung injury, as demonstrated by a significant fall in PaO(2) and an increase in intrapulmonary shunt compared with all groups (P<0.05). These changes were associated with significant pulmonary infiltration of neutrophils and an increase in elastase and MMP-9 activity.

CONCLUSIONS

All pathological changes typical of ALI after CPB were prevented by CMT-3. Prevention of lung dysfunction followed an attenuation of both elastase and MMP-2 activity. This study suggests that strategies to combat ARDS should target terminal neutrophil effectors.

Multiple sequential insults cause post-pump syndrome

BACKGROUND

We hypothesize that post-pump syndrome (PPS) following cardiopulmonary bypass (CPB) can be caused by multiple minor insults and that the mechanism of PPS is a priming and subsequent activation of polymorphonuclear (PMN) leukocytes. In this study extensive pathophysiologic and morphometric assessment was undertaken in a porcine model of sequential insult PPS.

METHODS

Pigs were anesthetized, placed on a ventilator, instrumented for measurements of hemodynamic function, and separated into five groups: (1) Control (n = 4)--surgery only, (2) CPB (n = 4)--placed on femoral-femoral hypothermic (28 degrees C) bypass for 1 h, (3) LPS (n = 6)--underwent sham CPB followed by infusion of low dose endotoxin [E. coli lipopolysaccharide (LPS-1 microg/kg)], (4) Heparin + protamine + LPS (HP + LPS, n = 4)--were heparinized without CPB for 1 h, following which protamine and LPS were infused and (5) CPB + LPS (n = 8)--subjected to both CPB and LPS.

RESULTS

Only CPB + LPS resulted in acute respiratory distress typical of PPS as indicated by a significant decrease in PaO2 and increase in intrapulmonary shunt fraction (p<0.05). CPB + LPS significantly increased tissue density and the number of sequestered monocytes and PMNs (p<0.05) above all other groups. Alveolar macrophages (AM) increased equally in all groups receiving LPS.

CONCLUSIONS

CPB primes the inflammatory system causing pulmonary PMN sequestration without lung injury. Exposure to an otherwise benign dose of endotoxin results in activation of the sequestered PMNs causing PPS. This study confirms that PPS can be caused by multiple minor insults.

Behavioral recovery associated with central nervous system regeneration in the snail Melampus

The pulmonate snail Melampus bidentatus regenerates central nervous tracts following commissurotomy, connective transection, and cerebral ganglion ablation. Our goal was to determine whether or not neural regrowth within the central nervous system restored behaviors disrupted by lesions. One behavior that is disrupted by commissurotomy is retraction of facial structures that are contralateral to a stimulated facial region, a response that normally accompanies the ipsilateral retraction. Tentacle withdrawal on the side contralateral to stimulation reappeared on a timescale that was correlated with growth of a commissural link (8-19 days post-lesion). Electrophysiological recordings from a labial nerve pathway that has a contralateral component similar to the contralateral tentacle response showed that development or strengthening of an alternative pathway could also mediate contralateral responses. Thus, a major conclusion of this study was that both tract regeneration and changes in existing CNS pathways can underlie recovery. The percentage (approx. 75%) of snails that regenerate the cerebral commissure and show behavioral recovery is established early in the period following commissure transection. Behavioral recovery and anatomical evidence of regeneration were also correlated in the other two operations: single cerebral ganglion removal and unilateral cerebropleural and cerebropedal connective transection. We conclude that Melampus is able to regenerate neuronal connectivity that can restore normal behavior.

The dexamethasone suppression test in normal control subjects: comparison of two assays and effect of age

he authors used competitive protein binding assay and radioimmunoassay to measure cortisol levels in 38 normal control subjects three times before and three times after administration of 1 mg of dexamethasone. They found significant interassay differences at 11:00 p.m. before dexamethasone and at all three postdexamethasone times. Analysis of variance revealed significant overall positive relationships between age and cortisol levels measured by both techniques. Age correlated significantly with postdexamethasone cortisol levels measured by radioimmunoassay but not when measured by competitive protein binding assay. Clinicians should obtain data from their laboratories as to appropriate cutoffs for cortisol suppression on the specific assay used.

Coexpression of the human papillomavirus type 16 E4 and L1 open reading frames in early cervical neoplasia

Although the E4 open reading frame (ORF) of human papillomaviruses (HPV) encodes an abundant protein in cutaneous warts, the location and extent of HPV E4 expression in genital precancers, specifically those associated with HPV-16, has not been described. Expression plasmids (pATH) containing segments of the HPV-16 E4 (3401-3620) and L1 (6151-6792) open reading frames (ORFs) were induced and expressed in bacteria and the resulting fusion proteins were used to elicit antisera in rabbits. Antisera reacting to the E4 and L1 components of the fusion proteins were used to screen biopsies from 150 cervical precancers (cervical intraepithelial neoplasia) and condylomata. Six biopsies exhibiting specific immunostaining with the anti-E4 sera. Staining was cytoplasmic, and occurred virtually always in foci containing immunostaining for L1 proteins. Moreover, analysis of these 6 cases and 22 others for HPV-16 RNA by RNA-RNA in situ hybridization demonstrated a similar correlation between E4 immunostaining and the presence of abundant transcripts specific to HPV-16. These data are consistent with the hypothesis that expression of the HPV-16 E4 ORF is dependent upon viral replication and epithelial differentiation, similar to L1 expression, and that the E4 epitopes identified by the rabbit antisera may be unique to HPV-16 relative to other common cervical papillomaviruses.

An alternative, human SRC promoter and its regulation by hepatic nuclear factor-1alpha

The SRC gene encodes the proto-oncogene pp60(c-)(src), a tyrosine kinase implicated in numerous signal transduction pathways. In addition, the SRC gene is differentially expressed, developmentally regulated, and frequently overexpressed in human neoplasia. However, the mechanisms regulating its expression have not been completely explored. Here we describe the isolation of a new distal SRC promoter and associated exon, designated 1alpha, which we mapped to a position 1.0 kilobase upstream of the previously described SRC1A housekeeping promoter. Differential use of these promoters and their associated exons coupled with subsequent splicing to a common downstream exon results in c-Src transcripts with different 5' ends but identical coding regions. Promoter analysis following transient transfections into HepG2 cells mapped the minimal 1alpha promoter to a region 145 bp upstream of the major transcription start site. This region contained a consensus binding site for hepatic nuclear factor-1 (HNF-1), a liver-enriched transcription factor implicated in the regulation of a number of genes in liver, kidney, stomach, intestine, and pancreas. Subsequent mobility shift assays confirmed that HNF-1alpha isoform was the predominant factor interacting with this region of the promoter. Mutation of the HNF-1 site resulted in a dramatic reduction in SRC promoter activity. Cotransfection studies demonstrated the promoter could be strongly transactivated by the HNF-1alpha isoform but not by the related HNF-1beta factor. Consistent with these results, we demonstrated that transcripts originating from the SRC1alpha promoter display a tissue restricted pattern of expression with highest levels present in stomach, kidney, and pancreas. These results indicate that SRC transcriptional regulation is much more complex than previously realized and implicates HNF-1 in both the tissue-specific regulation of the SRC gene in normal tissues and the overexpression of c-Src in certain human cancers.

Effect of modification of the basic residues of dynorphin A-(1-13) amide on kappa opioid receptor selectivity and opioid activity

A series of dynorphin A-(1-13) amide (Dyn A-(1-13)NH2) analogues containing lysine or N epsilon-acetyllysine (Lys(Ac)) was prepared by solid-phase peptide synthesis and evaluated for opioid receptor affinity in radioligand binding assays and for opioid activity in the guinea pig ileum (GPI). Substitutions were made at positions 6, 7, 9, 11, and 13, the basic amino acids in the C-terminus of the peptide, in order to assess the individual contributions of these residues to the kappa opioid receptor affinity and selectivity of Dyn A-(1-13)NH2. While substitutions of Lys(Ac) for Arg in position 6 did not affect kappa receptor affinity, it enhanced affinity for mu and delta receptors and therefore caused a loss of kappa receptor selectivity. When Lys(Ac) was substituted for Arg9, kappa opioid receptor affinity was enhanced and kappa receptor selectivity was retained. Replacement for Arg7, Lys11, or Lys13 by Lys(Ac) resulted in both decreased affinity and selectivity for kappa receptors. These results demonstrate the importance of Arg6 to the receptor selectivity profile of Dyn A-(1-13)NH2 and indicate that, of the five basic residues in the C-terminus, only Arg9 can be replaced by a nonbasic residue without substantial loss of kappa opioid receptor selectivity.

Predictors of vitamin D biochemical status in a large sample of middle-aged male smokers in Finland

BACKGROUND/OBJECTIVES

As vitamin D deficiency is considered to be more common in regions with little solar ultraviolet (UV) light in winter, the aim of this study was to analyze predictors of vitamin D status by season within a large sample of male smokers from Finland, a country where there is negligible solar UV light in winter.

SUBJECTS/METHODS

Vitamin D (measured by 25-hydroxyvitamin D (25(OH)D) nmol/l) and other serum constituents were assayed. Measured anthropometry, and self-reported dietary intake and physical activity (PA) were obtained and analyzed using stepwise multiple linear and logistic regression in 2271 middle-aged Finnish male smokers.

RESULTS

In all, 27% of the population in winter and 17% in summer had serum 25(OH)D levels of <25 nmol/l, respectively. In summer, in multiple logistic regression analyses with adjustment for confounding and other predictors, high vitamin D intake (odds ratios (OR) 3.6; 95% confidence interval (CI) 1.5-8.5), some leisure time PA (OR 2.0; 95% CI 1.3-3.1) and having a body mass index (BMI) of >or=21 kg/m(2) compared with <21 kg/m(2) (OR 2.6; 95% CI 1.3-5.0), were associated with 25(OH)D >or=25 nmol/l. In winter, additional modifiable factors were occupational PA (OR 1.6; 95% CI 1.1-2.5) and high fish (OR 3.1; 95% CI 1.7-6.2) or poultry consumption (OR 1.7; 95% CI 1.2-2.5). Predictors from linear regression analyses of continuous levels of 25(OH)D were similar to the logistic regression analyses of 25(OH)D >or=25 nmol/l.

CONCLUSION

In this Finnish sample more vitamin D intake, PA and having a BMI of >or=21 may have important modifiable roles in maintaining an adequate vitamin D status.

Catechol O-methyltransferase pharmacogenomics and selective serotonin reuptake inhibitor response

We applied a systematic pharmacogenetic approach to investigate the role of genetic variation in the gene encoding catechol O-methyltransferase (COMT) in individual variation in selective serotonin reuptake inhibitor (SSRI) response among depressed patients. In all, 23 single-nucleotide polymorphisms (SNPs) in COMT were genotyped using DNA from the Sequenced Treatment Alternatives to Relieve Depression (STAR(*)D) study (N=1914). One SNP, rs13306278, located in the distal promoter region of COMT, showed significant association with remission in White non-Hispanic (WNH) subjects (P=0.038). Electromobility shift assay for rs13306278 showed alternation in the ability of the variant sequence to bind nuclear proteins. A replication study was performed using samples from the Mayo Clinic Pharmacogenetics Research Network Citalopram/Escitalopram Pharmacogenomic study (N=422) that demonstrated a similar trend for association. Our findings suggest that novel genetic markers in the COMT distal promoter may influence SSRI response phenotypes.

Insulin-like growth factors and risk of kidney cancer in men

BACKGROUND

Insulin-like growth factor-I (IGF-I) has been shown to increase kidney growth, glomerular filtration rate, and renal function.

METHODS

In the prospective Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) study of 29 133 Finnish male smokers aged 50-69 years, serum concentrations of IGF were measured in samples collected in 1985-1988. A total of 100 men with kidney cancer diagnosed > or =5 years after blood collection through 1997 were compared with a subcohort of 400 men; logistic regression models were used to estimate the risk of developing kidney cancer.

RESULTS

Men with IGF-I levels >113 ng ml(-1) were 59% less likely to develop kidney cancer than men with levels < or =113 ng ml(-1) (odds ratio=0.41; 95% confidence interval=0.23-0.75). The IGF binding protein-3 (IGFBP-3) levels did not alter the association. No association was observed between IGFBP-3, or molar ratio of IGF-I/IGFBP-3, and kidney cancer.

CONCLUSIONS

Low serum IGF-I levels in this cohort of older middle-aged male smokers are associated with increased kidney cancer risk, independent of IGFBP-3.

Physiology, morphology, and ozone uptake of leaves of black cherry seedlings, saplings, and canopy trees

Patterns of ozone uptake were related to physiological, morphological, and phenological characteristics of different-sized black cherry trees (Prunus serotina Ehrh.) at a site in central Pennsylvania. Calculated ozone uptake differed among open-grown seedlings, forest gap saplings, and canopy trees and between leaves in the upper and lower crown of saplings and canopy trees. On an instantaneous basis, seedling leaves had the greatest ozone uptake rates of all tree size classes due to greater stomatal conductance and higher concentrations of ozone in their local environment. A pattern of higher stomatal conductance of seedlings was consistent with higher incident photosynthetically-active radiation, stomatal density, and predawn xylem water potentials for seedlings relative to larger trees. However, seedlings displayed an indeterminate pattern of shoot growth, with the majority of their leaves produced after shoot growth had ceased for canopy and sapling trees. Full leaf expansion occurred by mid-June for sapling and canopy trees. Because many of their leaves were exposed to ozone for only part of the growing season, seedlings had a lower relative exposure over the course of the growing season, and subsequently lower cumulative uptake, of ozone than canopy trees and a level of uptake similar to upper canopy leaves of saplings. Visible injury symptoms were not always correlated with patterns in ozone uptake. Visible symptoms were more apparent on seedling leaves in concurrence with their high instantaneous uptake rates. However, visible injury was more prevalent on leaves in the lower versus upper crown of canopy trees and saplings, even though lower crown leaves had less ozone uptake. Lower crown leaves may be more sensitive to ozone per unit uptake than upper crown leaves because of their morphology. In addition, the lower net carbon uptake of lower crown leaves may limit repair and anti-oxidant defense processes.

Large aperture harmonic conversion experiments at Lawrence Livermore National Laboratory

Large aperture harmonic conversion experiments to 2 omega (532 nm), 3 omega (355 nm), and 4 omega (266 nm) on the Argus laser at the Lawrence Livermore National Laboratory are described. Harmonically converted energies of up to 346 J have been generated at external conversion efficiencies of 83%. A discussion of the harmonic conversion experiments and a brief summary of enhanced 2 omega and 3 omega inertial confinement fusion target performances are provided.

Synthesis and opioid activity of dynorphin A-(1-13)NH2 analogues containing cis- and trans-4-aminocyclohexanecarboxylic acid

It has been proposed that the "message" sequence of dynorphin A (Dyn A) exists in an extended conformation in aqueous solution (Schiller, P. W. Int. J. Pept. Protein Res. 1983, 21, 307-312). Molecular modeling suggested that trans-4-aminocyclohexanecarboxylic acid (trans-ACCA) might function as a conformationally constrained replacement for Gly2-Gly3 of Dyn A in such an extended conformation. ACCA was synthesized by catalytic hydrogenation of p-aminobenzoic acid, and the cis and trans isomers were separated by fractional recrystallization. Analogues of Dyn A-(1-13)-NH2 containing cis- and trans-ACCA were prepared by solid-phase peptide synthesis using the Fmoc chemical protocol. Results from radioligand binding assays indicated that the peptides have modest affinity for kappa opioid receptors (Ki's = 9.1 and 13.4 nM for [cis-ACCA2-3]- and [trans-ACCA2-3]Dyn A-(1-13)NH2, respectively) and modest kappa-receptor selectivity (Ki ratio (kappa/mu/delta) = 1/13/210 and 1/21/103, respectively). [cis-ACCA2-3]- and [trans-ACCA2-3]Dyn A-(1-13)-NH2 are the first reported Dyn A analogues constrained in the "message" sequence that are selective for kappa receptors. The cis-ACCA analogue showed very weak opioid activity (IC50 = 4.0 microM) in the guinea pig ileum.

Lithium ion transport by erythrocytes of randomly selected blood donors and manic-depressive patients: lack of association with affective illness

The authors measured the in vitro lithium ion ratio and maximal rate of sodium-lithium countertransport in erythrocytes of 739 randomly selected blood donors and 42 manic-depressive patients to determine the frequency distributions of these two variables in a general population and their relationship to one another and to affective illness. A large interindividual variation was found for the ratio and countertransport, and there was evidence of bimodality in the frequency distributions for these two traits. There was a moderate negative correlation (r = -.61) between the ratio and countertransport for 126 individuals. Neither the ratio nor countertransport was found to be a useful marker for affective illness.