Marking Drosophila suzukii (Diptera: Drosophilidae) With Rubidium or 15N.

Drosophila suzukii Matsumura (Diptera: Drosophilidae) has caused significant economic damage to berry and stone fruit production regions. Markers that are systemic in plants and easily transferred to target organisms are needed to track D. suzukii exploitation of host resources and trophic interactions. High and low concentrations of the trace element, rubidium (Rb), and the stable isotope, 15N, were tested to mark D. suzukii larvae feeding on fruits of enriched strawberry plants grown in containers under greenhouse conditions. Fly marker content and proportion of flies marked 1, 7, and 14 d after emergence from enriched fruits and fly dry mass were analyzed. Nearly 100% of the flies analyzed 14 d after emerging from 15N-enriched plants were marked, whereas only 30-75% and 0-3% were marked 14 d after emerging from high and low Rb concentration plants, respectively. Rapid Rb decay, strong 15N persistence, and the economics of using these markers in the field to elucidate D. suzukii pest ecology are discussed.

Stress alters rates and types of loss of heterozygosity in Candida albicans.

UNLABELLED: Genetic diversity is often generated during adaptation to stress, and in eukaryotes some of this diversity is thought to arise via recombination and reassortment of alleles during meiosis. Candida albicans, the most prevalent pathogen of humans, has no known meiotic cycle, and yet it is a heterozygous diploid that undergoes mitotic recombination during somatic growth. It has been shown that clinical isolates as well as strains passaged once through a mammalian host undergo increased levels of recombination. Here, we tested the hypothesis that stress conditions increase rates of mitotic recombination in C. albicans, which is measured as loss of heterozygosity (LOH) at specific loci. We show that LOH rates are elevated during in vitro exposure to oxidative stress, heat stress, and antifungal drugs. In addition, an increase in stress severity correlated well with increased LOH rates. LOH events can arise through local recombination, through homozygosis of longer tracts of chromosome arms, or by whole-chromosome homozygosis. Chromosome arm homozygosis was most prevalent in cultures grown under conventional lab conditions. Importantly, exposure to different stress conditions affected the levels of different types of LOH events, with oxidative stress causing increased recombination, while fluconazole and high temperature caused increases in events involving whole chromosomes. Thus, C. albicans generates increased amounts and different types of genetic diversity in response to a range of stress conditions, a process that we term "stress-induced LOH" that arises either by elevating rates of recombination and/or by increasing rates of chromosome missegregation. IMPORTANCE: Stress-induced mutagenesis fuels the evolution of bacterial pathogens and is mainly driven by genetic changes via mitotic recombination. Little is known about this process in other organisms. Candida albicans, an opportunistic fungal pathogen, causes infections that require adaptation to different host environmental niches. We measured the rates of LOH and the types of LOH events that appeared in the absence and in the presence of physiologically relevant stresses and found that stress causes a significant increase in the rates of LOH and that this increase is proportional to the degree of stress. Furthermore, the types of LOH events that arose differed in a stress-dependent manner, indicating that eukaryotic cells generate increased genetic diversity in response to a range of stress conditions. We propose that this "stress-induced LOH" facilitates the rapid adaptation of C. albicans, which does not undergo meiosis, to changing environments within the host.

Technique to assess effectiveness of control tactics against Ostrinia nubilalis (Lepidoptera: Crambidae) in whorl-stage corn.

Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae) is one of the most damaging insect pests of corn. Studies were conducted to determine whether live larval counts obtained from corn whorls were predictive of the amount of larval tunneling that would result in the stalk of the plant 40 d later at the end of larval development. Whorls from plants treated with Dipel 10G (6,400 IU per whorl) and untreated controls, both infested with O. nubilalis neonates, were evaluated for the number of live larvae in 50 whorls 5, 7, 9, and 12 d after Bacillus thuringiensis (Berliner) (Bacillales: Bacillaceae) application. Forty days after larval infestation, 25 plants from each plot were split from tassel to base, and the length of larval tunneling was recorded. There was a strong relationship between numbers of live larvae in the plant whorl and the length of larval tunneling that resulted. While linear at each location, there was significant variation in the relationship among locations, indicating that comparisons could not be made between years or locations within a year. Blocks within a location on a given year did not vary significantly and reproducible results were obtained each year within a given location as well as on any of the whorl pulling dates evaluated. Because of its ease of use, predictability, and rapid return of results, we propose this technique as an additional method to shot-hole feeding and stalk splitting to evaluate the effectiveness of O. nubilalis management strategies.

Diagnostic ambiguities in a case of post-traumatic narcolepsy with cataplexy.

Narcolepsy arising from trauma can present particular problems of differential diagnosis. In this case study presentation the patient suffered a head trauma, without unconsciousness, and began to experience unusual episodic behaviours. Symptom presentation differed from the typical clinical manifestations of idiopathic narcolepsy leading to an 8-year search for a definitive diagnosis. Key relevant aspects that led to diagnostic ambiguities were the order of symptom development, negative for the antigen HLA DR2, significance of the Multiple Sleep Latency Test (MSLT) mean sleep latency versus number of sleep onset rapid eye movement periods, the somewhat atypical features of cataplexy, the coexistence of sleep apnoea, and the mildness of the original head injury. It is argued that cases of post-traumatic narcolepsy should be considered in the context of their clinical development over time and that practitioners should be aware that this form of narcolepsy can differ from the typical clinical history of idiopathic narcolepsy.

The use of cell salvage during radical retropubic prostatectomy: does it influence cancer recurrence?

OBJECTIVE: To assess whether there is a difference in the biochemical recurrence rate in patients who had radical retropubic prostatectomy (RRP) with or without cell salvage transfusion. PATIENTS AND METHODS: The records of 769 consecutive patients undergoing RRP between 1992 and 1998 were retrospectively reviewed. Patients having adjuvant hormonal treatment, postoperative external beam radiotherapy, or a follow-up of < 1 year were excluded from the analysis. The remaining 408 patients were categorized into three groups: 87 who received cell-salvaged blood using a commercial cell saver; 264 receiving only autologous transfusion; and 57 with no transfusion. Disease recurrence was defined as a prostate-specific antigen (PSA) level of> 0.2 ng/mL. Bivariate and multivariate logistic regression analyses were used to assess and compare the risk of cancer recurrence in the three groups. Covariates used in the multivariate analyses included Gleason score, preoperative PSA level, seminal vesicle involvement and surgical margins. RESULTS: The mean (range) follow-up was 40.2 (12-104) months; there were no significant differences among the groups in initial PSA level and Gleason score. In the multivariate logistic regression analysis, the initial PSA, Gleason score, seminal vesicle involvement and surgical margins, but not transfusion group, were independent predictors of recurrence. CONCLUSION: Cell salvage during RRP does not influence the recurrence of prostate cancer. Cell salvage is a safe method of transfusion during RRP.

Pharmacotherapy or psychotherapy?: effective treatment for FSD related to unresolved childhood sexual abuse.

Childhood sexual abuse (CSA) is the form of sexual victimization most correlated with sexual dysfunction in adulthood (Atkeson, Calhoun, Resick, & Ellis, 1994; Sarwer & Durlak, 1996; Laumann, Paik, & Rosen, 1999). The goal of this study was to address the sexual ramifications of unresolved CSA and consider the effectiveness of vasoactive pharmacotherapy, specifically sildenafil, for the treatment of women with unresolved CSA. The sample included 35 women (mean age, 45 years) who presented to a sexual health clinic and who were not of childbearing potential. Of the sample 7 women (23%) had a history of unresolved CSA. Following a psychosexual history and medical evaluation, all women were treated with 100 mg of sildenafil, to be used over a 6-week period at home. When home doses were complete, participants filled out the FIEI, a valid and reliable 5-item questionnaire asking about sexual response post sildenafil. Parameters of sexual response included vaginal lubrication, amount and quality of sensation, satisfaction with intercourse, and ability to reach orgasm. Trends were calculated comparing women with and without unresolved CSA history. A minority of women with CSA responded positively to sildenafil.

The impact of narcolepsy on psychological health and role behaviours: negative effects and comparisons with other illness groups.

OBJECTIVES: The study sought to (i) assess psychosocial adjustment, disruption due to symptoms, and medication problems in narcolepsy, (ii) determine how these variables changed with gender, age and medication status, and (iii) compare narcolepsy adjustment with three other illness groups. BACKGROUND: Psychosocial adjustment to an illness can be conceptualized in terms of people's ability to function in their life roles and assessed using the Psychosocial Adjustment to Illness Scale-Self Report (PAIS-SR) questionnaire. METHODS: Participants (n=129) were recruited via a support group using posted questionnaires. The PAIS-SR was supplemented with additional questionnaire material. RESULTS: Males were more vulnerable than females in terms of adjustment (notably health care orientation and sexual relationships) and younger narcoleptics may have particular vocational problems. Unmedicated narcoleptics were least inclined to participate in social/leisure activities. Reported disruption due to symptoms was strongly associated with both psychological distress and overall psychosocial adjustment and was most notable in those taking both stimulants and tricyclic antidepressants. Narcoleptics reported more adjustment problems in comparison to three other illness groups (cardiac, mixed cancer and diabetes). A table of normative PAIS-SR values for narcolepsy was developed. CONCLUSIONS: Poor adjustment in terms of health care orientation and psychological distress are of particular concern. Health care that can reduce the disruption due to symptoms is especially important for adjustment.

Interaction of Nosema pyrausta and temperature on Ostrinia nubilalis egg production and hatch.

Nosema pyrausta is an obligate pathogen causing reduced fecundity and longevity of Ostrinia nubilalis. This study was conducted to determine the combined effects of N. pyrausta infection and temperature on O. nubilalis egg production and hatch. N. pyrausta-infected and noninfected O. nubilalis were maintained in two different temperature regimes. The first regime allowed females to oviposit under optimum conditions (27 degrees C, 65% RH, 16:8 (L:D)), while females in the second regime were held initially under the same humidity and light conditions, but a constant temperature of 16 degrees C for 1 week after which they were transferred to optimum ovipositional conditions. Studies were performed initially with O. nubilalis populations and later with individual mating pairs. In studies with O. nubilalis populations, the mean number of eggs laid per female under optimum conditions was 660, while N. pyrausta-infected females held initially at 16 degrees C laid 116 eggs per female. In studies with individual mating pairs, N. pyrausta infection reduced egg production per female 53 and 11% in the 16 and 27 degrees C temperature regimes, respectively, compared to noninfected females under optimum conditions. Exposure to 16 degrees C temperatures early in the ovipositional period had a more profound impact on reducing egg production in N. pyrausta-infected than noninfected O. nubilalis.

Acute ultrastructural effects of MPTP on the nigrostriatal pathway of the C57BL/6 adult mouse: evidence of compensatory plasticity in nigrostriatal neurons.

Acute doses of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) elicited degenerative and apparently compensatory changes in the nigrostriatum of injected animals within 1 day of treatment. In the substantia nigra pars compacta (SNc), low-dose (20 mg/kg) administration elicited early degeneration of mitochondria in the absence of other effects. In the striatum, a low MPTP dose resulted in myelin unwinding, demyelination, cytoplasmic shrinkage, and disturbance of synaptic communication, as evinced by a profound reduction in synaptic vesicle production. High-dose (40 mg/kg) administration generated more drastic axonal degeneration leading to cell elimination in the striatum. At neither dose was mitochondrial disturbance evident in the striatum. Evidence is presented that darkened synaptic boutons, visible at this level of MPTP administration, were part of healthy enlarged axons with an elevated number of synaptic contacts. These spared neuronal processes, therefore, were hypothesized to compensate for the MPTP-induced death of dopaminergic neurons by adaptive structural modifications that would serve to enhance their functional capability.

The effects of sleep inertia on decision-making performance.

Sleep inertia, the performance impairment that occurs immediately after awakening, has not been studied previously in relation to decision-making performance. Twelve subjects were monitored in the sleep laboratory for one night and twice awoken by a fire alarm (slow wave sleep, SWS and REM sleep). Decision making was measured over 10 3-min trials using the 'Fire Chief' computer task under conditions of baseline. SWS and REM arousal. The most important finding was that sleep inertia reduces decision-making performance for at least 30 min with the greatest impairments (in terms of both performance and subjective ratings) being found within 3 min after abrupt nocturnal awakening. Decision-making performance was as little as 51% of optimum (i.e. baseline) during these first few minutes. However, after 30 min. performance may still be as much as 20% below optimum. The initial effects of sleep inertia during the first 9 min are significantly greater after SWS arousal than after REM arousal, but this difference is not sustained. Decision-making performance after REM arousal showed more variability than after SWS arousal. Subjects reported being significantly sleepier and less clear-headed following both SWS and REM awakenings compared with baseline and this was sustained across the full 30 min. In order to generalize this finding to real-life situations, further research is required on the effects of continuous noise, emotional arousal and physical activity on the severity and duration of sleep inertia.

Metamemory in narcolepsy.

People with narcolepsy consistently report diminished memory function attributable to the disorder, however, objective evaluations of memory performance in this clinical group remain inconclusive. Previous evaluations of these subjective experiences have been primarily anecdotal with subjects required to provide global assessments of their memory function. The present study aimed to evaluate subjective assessments of memory dysfunction more extensively comparing responses by narcoleptics, subjects experiencing excessive daytime sleepiness, and controls, on the Metamemory in Adulthood (MIA) questionnaire. The results of the study indicate that subjects with narcolepsy have lower self efficacy for memory performance than either of the comparison groups, despite there being no significant difference between groups in relation to knowledge based aspects of memory functioning. This lowered self efficacy in narcolepsy is expressed through increased anxiety about memory function, decreased evaluations of memory capacity and increased perceptions of memory decline in relation to the comparison groups. It is argued that the negative cognitive self evaluations of narcoleptics potentially arise as a consequence of global psychosocial adjustment difficulties.

Induction of visual imagery during NREM sleep.

In an attempt to induce eye movements (EMs) in non-rapid eye movement sleep, light and sound stimuli were presented to human subjects (at below-waking threshold) during stage 2 sleep. EMs were used as an indicator of ponto-geniculo-occipital (PGO) wave activity. When at least one concurrent EM in response to the stimuli was observed, the subjects were awakened and mentation reports collected. Compared to equivalent control periods with no stimulation, awakenings from the stage 2 stimulation condition showed a higher frequency of visual imagery reports, electroencephalogram alpha activity, and k-complexes. Additional control and stimulation conditions elicited from rapid eye movement sleep awakenings showed no significant differences in the frequency of visual imagery reports. When the amount of alpha activity before stage 2 awakenings from which imagery was reported was compared to that from which imagery was not reported, imagery awakenings showed significantly more alpha. Results can be interpreted as evidence for a link between PGO activity and dreaming in humans or in terms of an arousal-window hypothesis of visual hallucinations.

Hemostatic markers in acute ischemic stroke. Association with stroke type, severity, and outcome.

BACKGROUND AND PURPOSE: Hemostatic markers can identify activation of the coagulation system in stroke patients. We evaluated whether the levels of these markers at the time of stroke are correlated with stroke severity, type, or mortality. METHODS: We measured fibrinopeptide A, cross-linked D-dimer, and beta-thromboglobulin in 70 patients within 1 week of stroke. We examined the association between the level of each of these markers and survival. We adjusted for the possible confounding effect of age, stroke type, or stroke severity using a multivariate Cox proportional hazards model. RESULTS: The median follow-up was 1.22 years. Fourteen patients died during follow-up. Univariate survival analysis identified age (hazard ratio, 1.06; 95% confidence interval [CI], 1.00 to 1.12), stroke type (hazard ratio, 4.44; 95% CI, 1.29 to 15.23), initial Toronto Stroke Scale score (hazard ratio, 5.05; 95% CI, 2.08 to 12.27), cross-linked D-dimer (hazard ratio, 6.43; 95% CI, 2.83 to 14.62), fibrinopeptide A (hazard ratio, 2.14; 95% CI, 1.26 to 3.63), and beta-thromboglobulin (hazard ratio, 7.63; 95% CI, 2.22 to 26.28) as significantly associated with mortality. In a multivariate model, initial stroke severity and each of the hemostatic markers were independently associated with subsequent mortality. CONCLUSIONS: Elevated hemostatic markers after acute ischemic stroke identify patients with increased risk for mortality. This association appears to be independent of stroke severity or stroke type.

Sleepiness and performance in narcolepsy.

Previous attempts to investigate the relationship between sleepiness and performance for subjects with narcolepsy have been limited by both the ability of narcoleptic subjects to contain their sleepiness for brief testing periods and the potential lack of sensitivity of routine performance tasks to sleepiness induced changes. The present study developed a research protocol which allowed subjects with narcolepsy to express states of sleepiness and non sleepiness and to then compare the performance of subjects with narcolepsy to age, gender and IQ matched controls on tasks evaluating automatic, attentional and complex cognitive functioning. The results indicated that at high arousal subjects with narcolepsy performed as well as controls on automatic tasks suggesting that the capacity to perform for narcolepsy subjects is not restricted by physiological factors but is secondary to the effects of sleepiness. Comparison of both the within subject effects for narcolepsy subjects of the transition between high and low arousal states, and the between subject effects of low arousal for narcolepsy subjects compared to controls indicate that complex cognitive tasks are the most sensitive to arousal fluctuation. This study provides support for the subjective experiences of subjects with narcolepsy of diminished cognitive function associated with the disorder.

A comparison of idiopathic hypersomnia and narcolepsy-cataplexy using self report measures and sleep diary data.

Eighteen patients with idiopathic hypersomnia (IH) were compared with 50 patients with the narcoleptic syndrome of cataplexy and daytime sleepiness (NLS) using self report questionnaires and a diary of sleep/wake patterns. The IH group reported more consolidated nocturnal sleep, a lower propensity to nap, greater refreshment after naps, and a greater improvement in excessive daytime sleepiness since onset than the NLS group. In IH, the onset of excessive daytime sleepiness was predominantly associated with familial inheritance or a viral illness. Two variable--number of reported awakenings during nocturnal sleep and the reported change in sleepiness since onset--provided maximum discrimination between the IH and NLS groups. Confusional arousals, extended naps or nocturnal sleep, autonomic nervous system dysfunction, low ratings of medication effectiveness, or side effects of medication were not associated differentially with either IH or NLS.

Acute mood improvement after dextroamphetamine and methylphenidate in narcolepsy.

Mood changes following ingestion of dextroamphetamine (D-AMP) or methylphenidate (MPH) were examined in 40 narcoleptic patients. The Profile of Mood Status (POMS) and eight additional adjectives describing feelings were used to quantify changes in mood before taking stimulant medication and approximately 90 minutes after ingestion of medication. No significant differences were found between the effects of the two stimulants. When the data from D-AMP and MPH were combined, significantly higher ratings on the POMS factor of Vigour-Activity and the adjectives of 'confident', 'talkative' and 'competitive' were found. Lower ratings after medication were noted for the POMS factors of Fatigue-Inertia, Depression-Dejection and Confusion-Bewilderment (all P < 0.001). These effects are similar to those previously reported in normal subjects as well as in certain other patient populations. The findings indicate a possible therapeutic role of stimulant medication not only for the treatment of excessive sleepiness but also for improving affect, motor and mental vigour, and aspects of cognition.

Sleepiness after glucose in narcolepsy.

The issue of whether a high carbohydrate intake affects sleepiness and sleep variables has been studied in normals but not in patients suffering from narcolepsy, despite anecdotal evidence that sugars may facilitate sleepiness in this population. This study investigated whether the intake of 50 g glucose exacerbated sleepiness in narcolepsy subjects. A double-blind cross-over study, involving 12 narcolepsy subjects and 12 matched controls, measured behaviour after a light lunch supplemented with a drink of either 50 g glucose or placebo (artificially sweetened drink). The main dependent variables were the performance and EEG measures from the Wilkinson Auditory Vigilance Task (WAVT) and sleep variables from a 45 minute nap. The results indicate that in the narcolepsy subjects glucose was associated with decreased wake duration, reduced sleep onset latency and more spontaneous and induced sleep stage changes during the WAVT, while the nap revealed an increased intensity of sleepiness after glucose as measured by the Polygraphic Score of Sleepiness. Eleven of the twelve narcolepsy subjects showed increased REM duration in the nap after glucose. The findings are discussed in relation to serotonin synthesis, basal sleepiness and possible irregularities in the action of insulin.