Clustering of related individuals in a population of the Australian lizard, Egernia frerei

Stable social aggregations are rarely recorded in lizards, but have now been reported from several species in the Australian scincid genus Egernia. Most of those examples come from species using rock crevice refuges that are relatively easy to observe. But for many other Egernia species that occupy different habitats and are more secretive, it is hard to gather the observational data needed to deduce their social structure. Therefore, we used genotypes at six polymorphic microsatellite DNA loci of 229 individuals of Egernia frerei, trapped in 22 sampling sites over 3500 ha of eucalypt forest on Fraser Island, Australia. Each sampling site contained 15 trap locations in a 100 x 50 m grid. We estimated relatedness among pairs of individuals and found that relatedness was higher within than between sites. Relatedness of females within sites was higher than relatedness of males, and was higher than relatedness between males and females. Within sites we found that juvenile lizards were highly related to other juveniles and to adults trapped at the same location, or at adjacent locations, but relatedness decreased with increasing trap separation. We interpreted the results as suggesting high natal philopatry among juvenile lizards and adult females. This result is consistent with stable family group structure previously reported in rock dwelling Egernia species, and suggests that social behaviour in this genus is not habitat driven.

Mechanism-based inhibition of CYP activities in rat liver by fluoxetine and structurally similar alkylamines

1. The inhibition of cytochrome P450 (CYP)-mediated substrate oxidations by alkylamine-based drugs was investigated in rat hepatic microsomes. The effects of pre-incubation of the drugs with NADPH-fortified microsomes on inhibition potency was evaluated in relation to the formation of metabolite intermediate (MI) complexes with CYP in vitro. 2. The selective serotonin-reuptake inhibitor fluoxetine (FLU) emerged as a potent and preferential inhibitor of CYP2C11 in rat liver microsomes. After FLU biotransformation in NADPH-supplemented microsomes, IC50 values of 2 and 1 microM were determined against CYP2C11-dependent testosterone 2alpha- and 16alpha-hydroxylation; in the absence of pre-incubation, the corresponding IC50 values were 47 and 39 microM. MI complexation of CYP appeared to contribute significantly to inhibition by FLU, as evidenced by the 21% decrease in apparent microsomal CYP content produced by 50 microM FLU in the presence of NADPH. 3. The secondary amines nisoxetine (NIS), and especially, desipramine (DES) and nortriptyline (NOR), also inhibited CYP2C11 and generated MI complexes with microsomal CYP. In contrast, with the exception of SKF-525-A, tertiary alkylamines (10 compounds) inhibited specific CYP activities but did not form MI complexes. Pre-incubation of these agents with NADPH-supplemented microsomes did not enhance inhibition of CYP activities, thus suggesting that formation of inhibitory metabolites was minimal for these compounds. 4. These findings implicate drug-mediated MI complexation of CYPs in the inhibition of hepatic biotransformation processes by secondary alkylamines. In contrast, tertiary amines did not generate significant quantities of CYP-MI complexes under the test conditions. Despite their diffusion from the CYP active site, inhibition produced by tertiary amines and stable metabolites of other drugs may be significant. However, such inhibition would be of shorter duration than that from MI complexation, which involves quasi-covalent binding to the haem and prevention of oxygen activation.

On a roll: the process of initiation and cessation of problem gambling among adolescents

As gambling becomes more accessible and acceptable in society, problems associated with gambling and gaming have begun to affect ever increasing numbers of adolescents. Although restricted from most forms of gambling by law, many adolescents are finding a path into problem gambling. Some are becoming compulsive gamblers early in their gambling career, facing a future filled with consequences and problems. Understanding the pathway or process by which these adolescents become engaged in gambling behavior and how they can extricate themselves from this addictive behavior can enhance the efficiency and effectiveness of our interventions. This article offers a perspective on the initiation and cessation of compulsive gambling using the basic elements of the process of intentional behavior change outlined in the Stages of Change from the Transtheoretical Model. The process of initiation of a problematic behavior is similar to the process of modification or cessation of a problematic behavior in terms of these stages of change. With adolescents it is important to distinguish between the process of initiation, which has implications for prevention of gambling problems, and the process of cessation, which often necessitates the assistance of treatment. Creating interventions that parallel the process of change offers the potential for personalizing and potentiating efforts to reduce the prevalence and consequences associated with compulsive or pathological and problem gambling. Application of this model to gambling behavior offers a heuristic that is intriguing and requires substantiation through rigorous research.

Cognitive and psychosocial functioning of pediatric hematopoietic stem cell transplant patients: a prospective longitudinal study

A prospective longitudinal study of cognitive and psychosocial functioning in pediatric hematopoietic stem cell transplant (HSCT) patients was conducted on three occasions: pre-HSCT, 1 year post-HSCT, and 2 years post-HSCT. In contrast to the previous hypothesis that cognitive declines would occur as a result of HSCT treatment, it was hypothesized that (1) global cognitive functioning (IQ scores), as well as specific areas would remain stable over time; (2) pre-transplant functioning would be predictive of later functioning; and (3) age would be negatively related to cognitive functioning. Based on previous research it was further hypothesized: that (4) while declines in psychosocial functioning might be seen at 1 year, functioning would improve by 2 years. 153 children and adolescents were evaluated pre-HSCT and at 1 year, with 2 year data available for 74 children. Longitudinal analyses of Wechsler IQ data were completed on 100 children (longitudinal exact test) and 52 children (repeated measures analysis of variance. Results of cognitive assessment indicated (1) stability of IQ scores over time; and (2) that the strongest predictor was pre-HSCT cognitive functioning. Psychosocial assessment results indicated: (1) a low prevalence of behavioral and social problems; (2) stability in functioning over time; (3) pre-HSCT functioning strongly predictive of later functioning.

Relationship between change in balance and self-reported handicap after vestibular rehabilitation therapy

BACKGROUND AND PURPOSE

Dizziness and balance problems are two commonly reported symptoms of vestibular system disease, with subsequent alterations in lifestyle and reports of physical, functional and emotional handicap. Vestibular rehabilitation therapy (VRT) was developed to improve the functional status of patients with vestibular dysfunction. The aim of the present study was to investigate the relationship between change in balance performance and change in self-rated handicap after a four-week home exercise programme in 16 subjects with chronic vestibular disease.

METHOD

Before and after the treatment intervention, balance was tested by use of a Smart Balance Master (SBM) system (Neurocom International, Clackamas, OR, USA) and self-rated handicap was measured by use of the Dizziness Handicap Inventory (DHI).

RESULTS

Significant improvement was observed in both the SBM (p < 0.001) and DHI (p = 0.003) scores over the testing period. A moderately strong negative correlation existed between change in SBM and DHI scores (Spearman's r = -0.6). Further analysis using the DHI subscales indicated, however, that the emotional component showed no significant change over time, and a poor correlation with change in balance scores (Spearman's r = -0.39).

CONCLUSIONS

These results indicate that a home-based exercise programme can significantly improve balance abilities in people with chronic vestibular dysfunction, but that outcomes may be enhanced by addressing the emotional issues associated with their disability.

Autologous stem cell transplantation for paediatric-onset polyarteritis nodosa: changes in autoimmune phenotype in the context of reduced diversity of the T- and B-cell repertoires, and evidence for reversion from the CD45RO(+) to RA(+) phenotype

We have studied immune reconstitution in a patient with paediatric-onset polyarteritis nodosa treated with high-dose immunosuppressive agents followed by stem cell rescue. The patient developed several new autoimmune phenomena over the 18 months after immunosuppression and stem cell rescue. Flow cytometry, reverse transcription-polymerase chain reaction (RT-PCR) heteroduplex and isotype-specific RT-PCR analysis of immunoglobulin expression showed that the T- and B-cell repertoires were highly restricted in the first few months after treatment. The dominant T-cell clones seen after reconstitution were persistently expanded, were different from those which could be demonstrated before autologous stem cell transplantation, and were in the CD8(+) population. Our data also show that 12 months after treatment these expanded T-cell clones were within the CD45RA(+) population, suggesting that reversion from the CD45RO(+) to the CD45RA(+) phenotype had occurred in vivo.

Neurocognitive outcome in brain metastases patients treated with accelerated-fractionation vs. accelerated-hyperfractionated radiotherapy: an analysis from Radiation Therapy Oncology Group Study 91-04

PURPOSE

To evaluate neurocognitive outcome as measured by the Mini-Mental Status Examination (MMSE) among patients with unresectable brain metastases randomly assigned to accelerated fractionation (AF) vs. accelerated hyperfractionated (AH) whole-brain radiation therapy (WBRT).

METHODS AND MATERIALS

The Radiation Therapy Oncology Group (RTOG) accrued 445 patients with unresectable brain metastases to a Phase III comparison of AH (1.6 Gy b.i.d. to 54.4 Gy) vs. AF (3 Gy q.d. to 30 Gy). All had a KPS of >or= 70 and a neurologic function status of 0-2. Three hundred fifty-nine patients had MMSEs performed and were eligible for this analysis. Changes in the MMSE were analyzed according to criteria previously defined in the literature.

RESULTS

The median survival was 4.5 months for both arms. The average change in MMSE at 2 and 3 months was a drop of 1.4 and 1.1, respectively, in the AF arm as compared to a drop of 0.7 and 1.3, respectively, in the AH arm (p = NS). Overall, 91 patients at 2 months and 23 patients at 3 months had both follow-up MMSE and computed tomography/magnetic resonance imaging documentation of the status of their brain metastases. When an analysis was performed taking into account control of brain metastases, a significant effect on MMSE was observed with time and associated proportional increase in uncontrolled brain metastases. At 2 months, the average change in MMSE score was a drop of 0.6 for those whose brain metastases were radiologically controlled as compared to a drop of 1.9 for those with uncontrolled brain metastases (p = 0.47). At 3 months, the average change in MMSE score was a drop of 0.5 for those whose brain metastases were radiologically controlled as compared to a drop of 6.3 for those with uncontrolled brain metastases (p = 0.02).

CONCLUSION

Use of AH as compared to AF-WBRT was not associated with a significant difference in neurocognitive function as measured by MMSE in this patient population with unresectable brain metastases and limited survival. However, control of brain metastases had a significant impact on MMSE.

Phase II radiation therapy oncology group trial of weekly paclitaxel and conventional external beam radiation therapy for supratentorial glioblastoma multiforme

PURPOSE

Fractionated external beam radiotherapy (EBRT) +/- carmustine (BCNU) is the standard of care for patients with glioblastoma multiforme (GBM), but survival results remain poor. Preclinical studies indicate synergy between RT and paclitaxel (TAX) in astrocytoma cell lines. Phase I studies in GBM have demonstrated a maximum tolerated dose for TAX of 225 mg/m(2)/3 h/week x 6, during EBRT, with no exacerbation of typical RT-induced toxicities. The Radiation Therapy Oncology Group (RTOG) therefore mounted a Phase II study to determine the feasibility and efficacy of conventional EBRT and concurrent weekly TAX at its MTD.

PATIENTS AND METHODS

Sixty-two patients with histologic diagnosis of GBM were enrolled from 8/16/96 through 3/21/97 in a multi-institutional Phase II trial of EBRT and TAX 225 mg/m(2)/3 h (1-3 h before EBRT), administered the first treatment day of each RT week. Total EBRT dose was 60 Gy (200 cGy/fraction), 5 days per week. A smaller treatment field, to include gross disease plus a margin only, was used after 46 Gy.

RESULTS

Sixty-one patients (98%) were evaluable. Median age was 55 years (range, 28-78). Seventy-four percent were > or = 50 years. Recursive partitioning analysis (RPA) Classes III, IV, V, VI included 10 (17%), 21 (34%), 25 (41%), and 5 (8%) patients, respectively. Gross total resection was performed in only 16%. There was no Grade 3 or 4 neutropenia or thrombocytopenia. Hypersensitivity reactions precluding further use of TAX occurred in 4 patients. There were 2 instances of late neurotoxicity (4% Grade 3 or 4). Ninety-one percent of patients received treatment per protocol. Seventy-seven percent completed prescribed treatment (6 weeks). Of 35 patients with measurable disease, CR/PR was observed in 23%, MR in 17%, and SD in 43%. Seventeen percent demonstrated progression at first follow-up. Median potential follow-up time is 20 months. Median survival is 9.7 months, with median survivals for RPA classes III, IV, V, and VI of 16.3, 10.2, 9.5, 2.5 months, respectively. Ten patients remain alive.

CONCLUSION

Concurrent full-dose EBRT and weekly high-dose TAX is feasible in the majority of GBM patients. Acute toxicity is acceptable; myelosuppression and peripheral sensory neuropathy are surprisingly modest, despite considerably higher overall dose intensity, compared to that achievable in other disease sites. Median survival by RPA class without prolonged adjuvant therapy is comparable to RTOG controls treated with standard EBRT and BCNU (1 year of BCNU).

Neuregulin signaling regulates neural precursor growth and the generation of oligodendrocytes in vitro

Neuregulin 1 (Nrg-1) isoforms have been shown to influence the emergence and growth of oligodendrocytes, the CNS myelin-forming cells. We have investigated how Nrg-1 signaling of ErbB receptors specifically controls the early stages of oligodendrocyte generation from multipotential neural precursors (NPs). We show here that embryonic striatal NPs express multiple Nrg-1 transcripts and proteins as well as their specific receptors, ErbB2 and ErbB4, but not ErbB3. The major isoform synthesized by striatal NPs is a transmembrane type III isoform called cysteine-rich domain Nrg-1. To examine the biological effect of Nrg-1, we added soluble ErbB3 (sErbB3) to growing neurospheres. This inhibitor of Nrg-1 bioactivity decreased mitosis of NPs and increased their apoptosis, resulting in a significant reduction in neurosphere size and number. When NPs were induced to migrate and differentiate by adhesion of neurospheres to the substratum, the level of type III isoforms detected by RT-PCR and Western blot decreased in parallel with a reduction in Nrg-1 fluorescence intensity in differentiating astrocytes, neurons, and oligodendrocytes. Pretreatment of growing neurospheres with sErbB3 induced a threefold increase in the proportion of oligodendrocytes generated from NPs migrating out of the neurosphere. This effect was not observed with an unrelated soluble receptor. Addition of sErbB3 during NP growth and differentiation enhanced oligodendrocyte maturation as shown by expression of galactocerebroside and myelin basic protein. We propose that both type III Nrg-1 signaling and soluble ErbB receptors modulate oligodendrocyte development from NPs.

The outbreak of West Nile virus infection in the New York City area in 1999

BACKGROUND

In late August 1999, an unusual cluster of cases of meningoencephalitis associated with muscle weakness was reported to the New York City Department of Health. The initial epidemiologic and environmental investigations suggested an arboviral cause.

METHODS

Active surveillance was implemented to identify patients hospitalized with viral encephalitis and meningitis. Cerebrospinal fluid, serum, and tissue specimens from patients with suspected cases underwent serologic and viral testing for evidence of arboviral infection.

RESULTS

Outbreak surveillance identified 59 patients who were hospitalized with West Nile virus infection in the New York City area during August and September of 1999. The median age of these patients was 71 years (range, 5 to 95). The overall attack rate of clinical West Nile virus infection was at least 6.5 cases per million population, and it increased sharply with age. Most of the patients (63 percent) had clinical signs of encephalitis; seven patients died (12 percent). Muscle weakness was documented in 27 percent of the patients and flaccid paralysis in 10 percent; in all of the latter, nerve conduction studies indicated an axonal polyneuropathy in 14 percent. An age of 75 years or older was an independent risk factor for death (relative risk adjusted for the presence or absence of diabetes mellitus, 8.5; 95 percent confidence interval, 1.2 to 59.1), as was the presence of diabetes mellitus (age-adjusted relative risk, 5.1; 95 percent confidence interval, 1.5 to 17.3).

CONCLUSIONS

This outbreak of West Nile meningoencephalitis in the New York City metropolitan area represents the first time this virus has been detected in the Western Hemisphere. Given the subsequent rapid spread of the virus, physicians along the eastern seaboard of the United States should consider West Nile virus infection in the differential diagnosis of encephalitis and viral meningitis during the summer months, especially in older patients and in those with muscle weakness.

Updated results of the phase III Radiation Therapy Oncology Group (RTOG) trial 85-31 evaluating the potential benefit of androgen suppression following standard radiation therapy for unfavorable prognosis carcinoma of the prostate

PURPOSE

To determine the potential advantage of androgen ablation following standard external-beam radiation therapy in patients with locally advanced (clinical or pathologic T3; clinical or pathologic node positive) carcinoma of the prostate.

METHODS AND MATERIALS

In 1987 the RTOG initiated a Phase III trial of long-term adjuvant goserelin in definitively irradiated patients with carcinoma of the prostate. A total of 977 patients were accrued to the study of which 945 remain analyzable: 477 on the adjuvant hormone arm (Arm I); and 468 on the radiation only arm (Arm II) with hormones initiated at relapse. The initial results were reported in the Journal of Clinical Oncology in 1997.

RESULTS

With a median follow up of 5.6 years for all patients and 6.0 years for living patients local failure at 8 years was 23% for Arm I and 37% for Arm II (p < 0.0001). Distant metastasis was likewise favorably impacted with the immediate use of hormonal manipulation with a distant metastasis rate in Arm I of 27% and 37% in Arm II (p < 0.0001). Disease-free survival (NED survival) and NED survival with PSA of 1.5 ng/mL (bNED) or less were both statistically significant in favor of the immediate hormone arm (both p < 0.0001). Cause-specific failure was not statistically different with a cause-specific failure of 16% for Arm I and 21% in Arm II (p = 0.23). Overall survival was likewise not statistically different between two arms, with a 49% overall survival at 8 years in Arm I and 47% in Arm II (p = 0.36). Subset analysis of centrally reviewed Gleason 8-10 patients who did not undergo prostatectomy showed that for patients receiving radiation therapy plus adjuvant hormones there was a statistically significant improvement in both absolute (p = 0.036) and cause-specific survival (p = 0.019).

CONCLUSIONS

Use of long-term adjuvant androgen deprivation in addition to definitive radiation therapy results in a highly significant improvement in regards to local control, freedom from distant metastasis, and biochemical free survival in unfavorable prognosis patients with carcinoma of the prostate.

FKBP binding characteristics of cardiac microsomes from diverse vertebrates

FK506 binding protein (FKBP) is a cytosolic receptor for the immunosuppressive drug FK-506. The common isoform, FKBP12, was found to be associated with the calcium release channel (ryanodine receptor 1) of different species of vertebrate skeletal muscle, whereas 12.6, a novel FKBP isoform was found to be associated with canine cardiac ryanodine receptor (ryanodine receptor 2). Until recently, canine cardiac sarcoplasmic reticulum was considered to be the prototype for studying heart RyR2 and its interactions with FKBP. In this study, cardiac microsomes were isolated from diverse vertebrates: human, rabbit, rat, mice, dog, chicken, frog, and fish and were analyzed for their ability to bind or exchange with FKBP isoforms 12 and 12.6. Our studies indicate that RyR2 from seven out of the eight animals contain both FKBP12 and 12.6. Dog is the exception. It can now be concluded that the association of FKBP isoforms with RyR2 is widely conserved in the hearts of different species of vertebrates.

Unusual presentation of thoracic Pneumocystis carinii infection in a patient with acquired immunodeficiency syndrome

Pleura-based masses and hilar adenopathy were seen on a chest radiograph of a patient with acquired immunodeficiency syndrome who had a history of Pneumocystis carinii infection. The differential diagnosis of such a presentation is discussed in light of atypical and extrapulmonary manifestations of P. carinii infection in a patient receiving prophylaxis with dapsone.

Evaluating a telemedicine system to assist in the management of dermatology referrals

BACKGROUND

Teledermatology systems fall into two categories: live video or store-and-forward. In the former, video-conferencing equipment is used to connect a patient with a remote consultant. This method has been evaluated as an aid to dermatology, but it is expensive both in terms of capital and running costs. Video consultations are generally longer than conventional ones and harder to schedule. Some authors have considered store-and-forward as an alternative to live video: instead of a consultation, specialists could make a rapid inspection of a transmitted still image.

OBJECTIVES

A study was conducted to evaluate the role of telemedicine in the dermatology outpatients department of a district general hospital (Whittington Hospital NHS Trust, London, U.K.).

METHODS

One hundred and ninety-four patients were seen by one of two consultant dermatologists. A nurse used a video camera to store digital images of each patient's problem and compiled a history from the GP's referral letter. The images were reviewed 13 months later by both dermatologists; they recorded a provisional diagnosis and an assessment of how urgent an appointment would have been made given the information provided by the system. A third consultant graded the level of agreement between the telemedicine diagnoses and the face-to-face consultations.

RESULTS

High levels of agreement were found between the diagnoses of the dermatologists using the system to inspect images and those of the dermatologist who saw the patients (77%). Consultants using the system recommended fewer urgent appointments (32% compared with 64%) and felt that in 31% of cases the patient did not need to be seen. In 15% of these cases (5% of the total), however, their diagnosis differed significantly from that of the consultant who saw the patient. Had the system been in use, 14% of patients conventionally assigned a non-urgent appointment would have been seen urgently.

CONCLUSIONS

The images allowed a reasonably accurate diagnosis. The software was not reliable (six cases could not be viewed), or easy to use (it took approximately an hour to view 20 cases) but an improved version could be used in triaging outpatient appointments.

Electrodermal activity and temperament in preschool children

This study had two objectives: To examine poorly understood patterns of young children's electrodermal reactivity and to test the hypothesis that this reactivity reflects individual differences in the behavioral inhibition system (BIS). We recorded skin conductance responses (SCRs) from 92 4-year-old children during a laboratory session that encompassed physiological and psychological stimuli. Physiological stimuli (breaths), moderately loud to loud sounds (expected and unexpected) and, to a lesser extent, stimuli with psychological significance elicited clear SCRs. Induction of psychological conflict and exposure to emotional film clips for the most part did not elicit increases in skin conductance (SC). Children's temperament dimensions of fearfulness and effortful (or inhibitory) control--two components of the BIS--were assessed using robust observational batteries at age 2 and 4 years. The theoretically expected correlations between overall SC lability (reflecting SC levels) and both dimensions of temperament were significant, albeit modest and limited to the contemporaneous measures at age 4.