Asymmetric interaction between rod cyclic GMP phosphodiesterase gamma subunits and alphabeta subunits

Rod phosphodiesterase (PDE6) is the central effector enzyme in vertebrate visual transduction. Holo-PDE6 consists of two similar catalytic subunits (Palphabeta) and two identical inhibitory subunits (Pgamma). Palphabeta is the only heterodimer in the PDE superfamily, yet its significance for the function of PDE6 is poorly understood. An unequal interaction of Pgamma with Pbeta as compared with Palpha in the PDE6 complex has not been reported. We investigated the interaction interface between full-length Pgamma and Palphabeta, by differentiating Pgamma interaction with each individual Palphabeta subunit through radiolabel transfer from various positions throughout the entire Pgamma molecule. The efficiency of radiolabel transfer indicates that the close vicinity of serine 40 on Pgamma makes a major contribution to the interaction with Palphabeta. In addition, a striking asymmetry of interaction between the Pgamma polycationic region and the Palphabeta subunits was observed when the stoichiometry of Pgamma versus the Palphabeta dimer was below 2. Preferential photolabeling on Pbeta from Pgamma position 40 and on Palpha from position 30 increased while lowering the Pgamma/Palphabeta ratio, but diminished when the Pgamma/Palphabeta ratio was over 2. Our finding leads to the conclusion that two classes of Pgamma binding sites exist on Palphabeta, each composed of GAF domains in both Palpha and Pbeta, differing from the conventional models suggesting that each Pgamma binds only one of the Palphabeta catalytic subunits. This new model leads to insight into how the unique Palphabeta heterodimer contributes to the sophisticated regulation in visual transduction through interaction with Pgamma.

Transgenic Pinus radiata from Agrobacterium tumefaciens-mediated transformation of cotyledons

A method for Agrobacterium tumefaciens-mediated transformation of Pinus radiata cotyledon explants was developed using commercially available open-pollinated seed. Pinus radiata is the most widely planted commercial conifer species in the Southern Hemisphere. Reports on transformation of this species have relied on particle bombardment of embryogenic callus derived from immature embryos. The main drawback to the method is the small number of genotypes that are amenable to transformation and regeneration. Since more than 80% of genotypes of radiata pine can be regenerated using cotyledons from mature seed, cotyledon explants were cocultivated with A. tumefaciens strain AGL1 containing a plasmid coding for the neomycin phosphotransferase II (nptII) gene and the beta-glucuronidase (GUS) gene (uidA). Transformed shoots were selected using either geneticin or kanamycin. Critical factors for successful transformation were survival of the cotyledons after cocultivation and selection parameters. Of the 105 putative transformants that were recovered from selection media, 70% were positive for integration of the nptII gene when analysed by PCR. GUS histochemical assay for uidA expression was unreliable because of reaction inhibition by unidentified compounds in the pine needles. Further, only 4 of the 26 independent transformants characterised by PCR and Southern analysis contained an intact copy of both genes. The remaining 22 transformants appeared to have a truncated or rearranged copy of the T-DNA. It is possible that the truncation/rearrangements are due to the Cauliflower mosaic virus (CaMV) 35S promoter. Analysis of the T-DNA junction sites and sequencing of the introduced DNA will help elucidate the nature of T-DNA insertion so that genetic modification of radiata pine can be targeted effectively.

Comorbidity of impulse control disorders in pathological gamblers

OBJECTIVE

To investigate the rate of impulse control disorders among pathological gamblers and examine the relationship of comorbidity to gambling severity.

METHOD

Ninety-six adult pathological gamblers [mean age: 46.7 +/- 11.0 years; female: 44 (45.8%)] completed the following: Minnesota Impulsive Disorders Interview, Yale-Brown Obsessive-Compulsive Scale Modified for Pathological Gambling, and Gambling Symptom Assessment Scale.

RESULTS

Twenty-two subjects (22.9%) reported a comorbid impulse control disorder, most commonly compulsive sexual behaviour and compulsive buying. Subjects with comorbidity reported significantly greater intensity of urges (t = -2.021; df = 94; P = 0.046) and thoughts (t = -2.147; df = 42.3; P = 0.038) related to gambling, and greater interference (t = -3.913; df = 48.1; P < 0.001) and distress (t = -2.504; df = 52.7; P = 0.015) secondary to gambling urges and thoughts.

CONCLUSION

Impulse control disorders appear common among pathological gamblers and are associated with more severe gambling symptoms.

Influence of Agrobacterium tumefaciens strain on the production of transgenic peas ( Pisum sativum L.)

We compared the efficiency of two Agrobacterium tumefaciens strains, AGL 1 and KYRT1, for producing transgenic pea plants. KYRT1 is a disarmed strain of Chry5 that has been shown to be highly tumourigenic on soybean. The efficacies of the strains were compared using cotyledon explants from three pea genotypes and two plasmids. The peas were sourced from field-grown plants over three Southern Hemisphere summer seasons. Overall, KYRT1 was found to be on average threefold more efficient than AGL 1 for producing transgenic plants. We suggest that KYRT1 is sensitive to cocultivation temperature as the expected increase in efficiency was not achieved at high laboratory temperatures.

Treatment of compulsive sexual behaviour with naltrexone and serotonin reuptake inhibitors: two case studies

Although there is no universally accepted definition of compulsive sexual behaviour (CSB), the term is generally used to indicate excessive sexual behaviour or sexual cognitions that lead to subjective distress, social or occupational impairment, or legal and financial consequences. Similar to impulse control disorders, CSB is characterized by a failure to resist the impulse for sex. Opioid antagonists have been effective in treating urge-driven disorders, such as pathological gambling disorder, alcoholism, borderline personality disorder with self-injurious behaviour, cocaine abuse, mental retardation with self-injurious behaviour and eating disorders. Based upon the efficacy of opioid antagonists in treating disorders associated with urges, we hypothesized that naltrexone would reduce both the urges associated with CSB and therefore reduce the sexual behaviour. We present two case reports of individuals with CSB treated successfully with naltrexone, a novel treatment for CSB. In both cases, symptoms dramatically decreased and psychosocial functioning improved with the use of naltrexone. Although more research is needed to determine the mechanism that leads to the excessive sexual behaviour in individuals with CSB, the present case reports suggest that naltrexone may be effective in treating some cases of CSB.

Adolescent kleptomania treated with naltrexone--a case report

Kleptomania, an often secret inability to resist the impulse to steal objects not needed for personal use or their monetary value, is an underrecognized disorder that is unknown to many clinicians. Kleptomania has gone virtually non mentioned in the adolescent literature, despite the fact that kleptomania often has its onset during adolescence. This report presents a case of an adolescent with kleptomania who responded to naltrexone. The clinical features of kleptomania are reviewed, as are available data on the treatment of this distressing and often disabling disorder.

Characteristics of geriatric patients seeking medication treatment for pathologic gambling disorder

This study was constructed to compare geriatric patients seeking medication treatment for pathologic gambling disorder (PGD) with younger pathologic gamblers. This comparison study assessed three groups with PGD according to the Diagnostic and Statistical Manual of Mental Disorders, fourth edition: 16 subjects over the age of 60 years, 11 subjects between the ages of 20 and 30 years, and 46 subjects between the ages of 40 and 50 years. All subjects were evaluated in terms of demographic characteristics, clinical features of PGD, and treatment history. Geriatric gamblers had a later age of onset of gambling and developed pathologic gambling over a longer period of time. Geriatric subjects were more likely to play slot machines and demonstrate less variety in their choice of gambling activity. Geriatric gamblers were also more likely to gamble secondary to boredom. Geriatric subjects were as likely as the other age groups to report slight or no response to nonpharmacologic treatment. There appear to be some differences in the clinical features of PGD among geriatric subjects, and these differences may have treatment implications.

Demographic and clinical features of 131 adult pathological gamblers

BACKGROUND

This study was constructed to detail the demographic and phenomenological features of pathological gamblers.

METHOD

One hundred thirty-one subjects with DSM-IV pathological gambling were administered a semistructured interview to elicit demographic data and information on the phenomenology, age at onset, course, associated features, treatment history, and response to treatment of the disorder, followed by the Structured Clinical Interview for DSM-IV.

RESULTS

Seventy-eight female (59.5%) and 53 male (40.5%) (mean +/- SD age = 47.7+/-11.0 years) pathological gamblers were studied. The majority of subjects (55.7%) were married. Subjects gambled a mean of 16 hours per week. Slot machines (65%), cards (33%), and blackjack (26%) were the most popular forms of gambling. The mean length of time between first gambling behavior and onset of pathological gambling was 6.3+/-8.9 years. Approximately one half (46%) of the subjects reported that television, radio, and billboard advertisements were a trigger to gamble. Most gamblers had severe financial, social, or legal problems. The majority of the subjects (58%) had at least 1 first-degree relative who also exhibited symptoms of problematic gambling behavior.

CONCLUSION

Pathological gambling is a disabling disorder associated with high rates of social and legal difficulties.

A case of kleptomania and compulsive sexual behavior treated with naltrexone

Objective of this paper was to examine a possible treatment option for two disorders currently lacking agreed upon pharmacotherapeutic interventions. We report a patient fulfilling DSM-IV criteria for kleptomania with comorbid compulsive sexual behavior who failed to respond to fluoxetine, behavioral therapy, and psychotherapy, and who was therefore treated with naltrexone to reduce urges to steal and sexual urges. Treatment with high-dose naltrexone (150 mg/day) led to remission of both the patient's urges to steal and sexual urges. Discontinuation and rechallenge with the medication provides further support that improvement was due to naltrexone. Naltrexone in high doses show promise for the treatment of both kleptomania and compulsive sexual behavior.

Personality dimensions in pathological gambling disorder and obsessive-compulsive disorder

This study was conducted to investigate the similarities and differences in the personality dimensions of patients with pathological gambling disorder (PGD) and obsessive-compulsive disorder (OCD). Thirty-three subjects with PGD, 41 with OCD and 40 normal controls were assessed with the Tridimensional Personality Questionnaire (TPQ), which assesses three personality dimensions: novelty seeking, reward dependence, and harm avoidance. Compared with OCD subjects, PGD subjects expressed significantly greater novelty seeking, impulsiveness, and extravagance. The PGD subjects also reported significantly less anticipatory worry, fear of uncertainty, and harm avoidance than the OCD subjects. Compared with controls, the PGD subjects expressed significantly greater novelty seeking, impulsiveness, and extravagance. These results suggest that the personality dimensions of pathological gamblers may differ significantly from both those of OCD patients and normal controls.

Changes in psychiatric consultations over ten years

We report on the day-to-day functions of a consultation-liaison psychiatric service during a two-month period separated by ten years. As general hospitals transformed their delivery of services during the 1990s, we hypothesized that the day-to-day role of the consultation-liaison service would change in terms of the population served, timing of evaluations, and recommended interventions. Using a chart review, we retrospectively examined consultations referred to an adult consultation-liaison service at a university hospital during the same two-months in 1990 (N=75) and 2000 (N=90). Patients in 2000 were less educated, more likely to be divorced and more likely to be minorities. The 2000 patients appeared to have more severe psychiatric illness and to be more medically complicated. These findings have implications in the context of cost effective health care.

Treatment of agitation and aggression in four demented patients using ECT

Electroconvulsive therapy (ECT) has been shown to be effective in treating the behavioral symptoms associated with psychiatric disorders in demented patients. Four case studies are presented that show its efficacy in treating behavioral symptoms in demented patients. We suggest that ECT is beneficial in these potentially life-threatening behavioral disturbances.

An open naltrexone treatment study in pathological gambling disorder

The present study was designed to test the short-term efficacy and safety of naltrexone in the treatment of pathological gambling disorder. Seventeen subjects (seven men, 10 women) who fulfilled DSM-IV criteria for pathological gambling disorder, and were free from other Axis I diagnoses by Structured Clinical Interview for DSM-III-R screening, participated in a 6-week open naltrexone flexible dose trial. Gambling symptom change was assessed with the patient-rated Clinical Global Impression (CGI) Scale, the clinician-rated CGI and the Gambling Symptom Assessment Scale. Side-effects were monitored weekly and liver function tests biweekly. Naltrexone reduced urges to gamble and gambling behaviour. The mean change in gambling frequency per week was 1.40 +/- 0.28 episodes per week; the mean change in dollars lost per week was $66.95 +/- 13.77; and the mean change in clinician-rated CGI Improvement was 0.40 +/- 0.04. Of those who responded to the medication, the majority had done so by the end of the fourth week. Men responded to naltrexone as well as women. The average naltrexone dose required for effective symptom control was 157 mg/day. Nausea was common during the first week (47%). The present findings provide evidence that naltrexone may be effective in the treatment of pathological gambling disorder. The present report is preliminary and controlled trials are needed to confirm these findings.

The psychopharmacology of pathological gambling

We discuss the rationale of the pharmacological approaches to pathological gambling and review the current status of drug treatments in this area. Specifically, we summarize the treatment study results of serotonin reuptake inhibitors, mood stabilizers, and opioid antagonists in pathological gambling. We also briefly describe the animal and human studies of other pharmacologic agents that show future promise in treating this disorder. Finally, we discuss a research agenda to be addressed in future drug treatment studies in pathological gambling.

Prevalence and clinical features of body dysmorphic disorder in adolescent and adult psychiatric inpatients

BACKGROUND

The rate of body dysmorphic disorder (BDD) in inpatient psychiatric settings and the nature of the presenting complaints are unknown. Because of the shame and humiliation that BDD patients suffer, we hypothesized that, unless specifically screened for at the time of admission, BDD would be underdiagnosed in psychiatric inpatients.

METHOD

101 consecutive adult patients and 21 consecutive adolescent patients presenting for psychiatric inpatient admission to a university teaching hospital participated in the study. Subjects completed the Body Dysmorphic Disorder Questionnaire, a brief self-report measure that screens for BDD, and a follow-up interview was conducted using a reliable clinician-administered semistructured diagnostic instrument for DSM-IV BDD. Data concerning current diagnoses, number of hospitalizations, number of suicide attempts, and current level of functioning were also obtained.

RESULTS

Sixteen (13.1%) of the 122 subjects were diagnosed with BDD. None of the subjects with BDD had been diagnosed with BDD by their treating physician during hospitalization. All 16 subjects reported that they would not raise the issue with their physician unless specifically asked due to feelings of shame.

CONCLUSION

These preliminary results suggest that BDD, an underrecognized and often severe psychiatric disorder, may be relatively common in the psychiatric inpatient setting. It is important that clinicians specifically inquire about BDD because patients will not voluntarily raise these concerns. The comorbidity of this disorder with other psychiatric illnesses may have treatment implications.

Double-blind naltrexone and placebo comparison study in the treatment of pathological gambling

BACKGROUND

The authors' goal was to assess the efficacy and tolerability of naltrexone in the treatment of pathologic gambling disorder.

METHODS

Eighty-three subjects who met criteria for DSM-IV pathologic gambling disorder were enrolled in a 1-week single-blind placebo lead-in followed by an 11-week double-blind naltrexone or placebo trial. Naltrexone was started at 25 mg/day and titrated upward until maximum symptom improvement or 250 mg/day was achieved. Gambling symptom change was assessed with the patient-rated Clinical Global Impression (PG-CGI-PT), clinician-rated CGI (PG-CGI-MD), and the Gambling Symptom Rating Scale (G-SAS). Side effects were monitored weekly and liver function tests biweekly.

RESULTS

Data from 45 patients were analyzed. Using random regression analysis, significant improvement was noted in all three gambling symptom measures: patient-rated Clinical Global Impression, p <.001; clinician-rated CGI, p <.001; Gambling Symptom Rating Scale, p <.019. At study end, 75% of subjects taking naltrexone were much or very much improved on both the PE-CEI PT and the PG-CGI-MD, compared with only 24% of those on placebo. Elevated liver enzymes occurred in four subjects who were taking analgesics concurrently. Nausea was common during the first week of treatment.

CONCLUSIONS

Results suggest that naltrexone is effective in reducing the symptoms of pathologic gambling. Until further studies corroborate the present findings, our report should be interpreted cautiously.

Prospective evaluation of Roux-en-Y gastric bypass as primary operation for medically complicated obesity

OBJECTIVE

To determine prospectively the results of Roux-en-Y gastric bypass (RYGB) used as the primary weight-reducing operation in patients with medically complicated ("morbid") obesity. The RYGB procedure combines the advantages of a restrictive physiology (pouch of 10 mL) and a "dumping physiology" for high-energy liquids without requiring an externally reinforced (banded) stoma.

PATIENTS AND METHODS

Between April 1987 and December 1998, a total of 191 consecutive patients with morbid obesity (median weight, 138 kg [range, 91-240 kg]; median body mass index, 49 kg/m2 [range, 36-74 kg/m2]), all of whom had directly weight-related morbidity, underwent RYGB and prospective follow-up.

RESULTS

Hospital mortality was 0.5% (1/191), and hospital morbidity occurred in 10.5% (20/191). Good long-term weight loss was achieved, and patients adapted well to the required new eating habits. The mean +/- SD weight loss at 1 year after operation (113 patients) was 52 +/- 1 kg or 68% +/- 2% of initial excess body weight. By 3 years postoperatively (74 patients), weight loss was still 66% +/- 2% of excess body weight. Overall, 53 (72%) of 74 patients had achieved and maintained a weight loss of 50% or more of their preoperative excess body weight 3 years after the operation. In addition, only 1 (1%) of 98 patients had persistent postoperative vomiting 1 or more times per week.

CONCLUSION

We believe that RYGB is a safe, effective procedure for most patients with morbid obesity and thus may be the current procedure of choice in patients requiring bariatrics++ surgery for morbid obesity.

Standardized evaluation of work capacity

A standardized method of evaluation of the work capacity of persons who are impaired by soft-tissue injuries is described. A demonstration project which involved testing 64 impaired subjects is described. The Cal-FCP test battery can be administered independently by a properly trained professional or by a technician under a physician's supervision and requires two hours or less to complete. This study demonstrated that the results of the test battery are unbiased in terms of both gender and age and can be applied to a standardized disability rating system.

Transformation of peas (Pisum sativum L.) using immature cotyledons

A reliable Agrobacterium tumefaciens-mediated transformation method has been developed for peas (Pisum sativum) using immature cotyledons as the explant source. Transgenic plants were recovered from the four cultivars tested: Bolero, Trounce, Bohatyr and Huka. The method takes approximately 7 months from explant to seed-bearing primary regenerant. The binary vector used carried genes for kanamycin and phosphinothricin resistance. Transformed pea plants were selected on 10 mg/l phosphinothricin. The nptII and bar genes were shown to be stably inherited through the first sexual generation of transformed plants. Expression of the phosphinothricin-resistance gene in the transformed plants was demonstrated using the 'Buster' (='Basta') leaf-paint test and the phosphinothricin acetyl transferase enzyme assay.

A test to measure lift capacity of physically impaired adults. Part 1--Development and reliability testing

STUDY DESIGN

Two laboratory studies and one field study evaluated the safety and test-retest reliability of a new test of lift capacity. The first two studies were conducted in a carefully controlled laboratory setting. The first study investigated the safety and intra-rater reliability of the EPIC Lift Capacity test protocol with healthy adult subjects. The second study assessed the safety and inter-rater reliability of the test with disabled subjects. The third study was conducted in the field with 65 evaluators and investigated the safety and intra-rater reliability of the test with healthy adult subjects.

OBJECTIVE

To assess the safety and reliability of a new test of lift capacity.

SUMMARY OF BACKGROUND DATA

A new test of lift capacity has been developed. Test development occurred within the context of ergonomic standards and guide-lines of the major professional associations and public agencies that govern test development in the United States.

METHODS

In study no. 1, 26 healthy subjects participated. In study no. 2, 14 disabled subjects participated. In study no. 3, 318 healthy subjects participated. After subjects underwent basic screening and warm-up, the EPIC Lift Capacity test was administered. One to 2 weeks later, the test was administered again. Correlations between the times of testing were calculated.

RESULTS

No subjects were injured. Hamstring soreness the next day that resolved without complication was reported by some healthy subjects. None of the disabled subjects reported new symptoms.

CONCLUSION

The safety and reliability of the EPIC Lift Capacity test was adequately demonstrated in a laboratory setting and across multiple field sites with evaluators who have varying types and degrees of professional preparation.

A test to measure lift capacity of physically impaired adults. Part 2--Reactivity in a patient sample

STUDY DESIGN

Test reactivity is the based on the idea that experience with a test may affect performance on subsequent tests, independent of what the test purports to measure. The reactivity of a test of lift capacity was studied in a single-blind randomized clinical trial was studied in a single-blind randomized clinical trial in which subjects were assigned to one or two groups. One group received lift testing before and after a therapeutic trial, while the other group received lift testing only at the conclusion of the therapeutic trial.

OBJECTIVE

To measure the reactivity of a lift capacity test over the course of treatment.

SUMMARY OF BACKGROUND DATA

The reactivity of a test is an important criterion by which an outcome measure must be judged. Change in response to treatment is assumed to be independent of changes resulting from the evaluee's experience with the test, although this is rarely addressed.

METHODS

The EPIC Lift Capacity test was administered to 55 patients with low back pain in a treatment program after they were randomized into a pre-test/post-test and a post-test only group. Additional measures were taken on a pre-test/post-test basis for all subjects.

RESULTS

Analyses of variance demonstrated no difference between the randomized groups after treatment. However, the pre-test/post-test group demonstrated significant improvement over the course of treatment. Other measures of outcome were similarly affected.

CONCLUSION

The reactivity of the EPIC Lift Capacity test was negligible over an 8-week treatment regimen that did not include lifting tasks.

Validity and reliability of a new device to simulate upper extremity work demands

The device validity, intra-test reliability, and test-retest reliability of the LIDO WorkSET(TM) (Loredan Biomedical, West Sacramento, California) was studied. Subjects were 30 healthy incumbent workers at a manufacturing and warehousing facility. The results of this study demonstrate a very high degree of device validity in terms of torque measurements, power, and work. In addition, the test protocols were found to be reliable on an intra-test and inter-test basis. Finally, inter-test comparisons were found to be stable over time.