Polyploidy, phylogeography and Pleistocene refugia of the rockfern Asplenium ceterach: evidence from chloroplast DNA

Chloroplast DNA sequences were obtained from 331 Asplenium ceterach plants representing 143 populations from throughout the range of the complex in Europe, plus outlying sites in North Africa and the near East. We identified nine distinct haplotypes from a 900 bp fragment of trnL-trnF gene. Tetraploid populations were encountered throughout Europe and further afield, whereas diploid populations were scarcer and predominated in the Pannonian-Balkan region. Hexaploids were encountered only in southern Mediterranean populations. Four haplotypes were found among diploid populations of the Pannonian-Balkans indicating that this region formed a northern Pleistocene refugium. A separate polyploid complex centred on Greece, comprises diploid, tetraploid and hexaploid populations with two endemic haplotypes and suggests long-term persistence of populations in the southern Mediterranean. Three chloroplast DNA (cpDNA) haplotypes were common among tetraploids in Spain and Italy, with diversity reducing northwards suggesting expansion from the south after the Pleistocene. Our cpDNA and ploidy data indicate at least six independent origins of polyploids.

Neurological and perceptual-motor outcome at 5 - 6 years of age in children with neonatal encephalopathy: relationship with neonatal brain MRI

OBJECTIVE

The aims of this study were 1) to determine the incidence of minor neurological dysfunction and perceptual-motor difficulties in children aged 5-1/2 -- 6-1/2, who had been born full-term but presented with neonatal encephalopathy (NE) and low Apgar scores and 2) to examine the relationships between the presence/absence of these difficulties with neonatal brain MRI.

PARTICIPANTS AND METHODS

Sixty-eight full-term infants with one minute Apgar scores less than or equal to 5 and neurological abnormalities during the first 48 hours after birth were included in the study. All children had a neonatal MRI brain scan. Surviving infants were assessed between the age of 5 and 6 years using the Touwen Examination, the Movement ABC and the WPPSI-R.

RESULTS

Fifteen of the 68 infants (22 %) died in the neonatal period. Of the 53 surviving infants, 19 (36 %) had cerebral palsy. The remaining 34 were considered normal at 2 years of age but, when assessed at school age, 8 (15 %) had minor neurological dysfunction and/or perceptual-motor difficulties, 1 (2 %) had only cognitive impairment and 25 (47 %) were normal. The outcome largely reflected the pattern of lesions on brain imaging. While 83 % of those with a normal outcome had normal scans or minimal white matter lesions, 80 % of those with minor neurological dysfunction and/or perceptual-motor difficulties had mild or moderate basal ganglia or more marked white matter lesions.

CONCLUSION

Continued surveillance is recommended for children with apparently normal outcome at two years of age after NE, particularly when abnormalities are detected on brain MRI.

The use of divalproex in alcohol relapse prevention: a pilot study

Anticonvulsant agents show promise in the treatment of the acute symptoms of alcohol withdrawal and may also treat some symptoms associated with the protracted abstinence syndrome. Impulsivity, hostility and irritability are common characteristics of alcohol-dependent individuals, and there is some evidence that anticonvulsant agents decrease these traits in individuals with a number of different psychiatric disorders. This pilot study is a 12-week, double-blind, placebo-controlled trial of an anticonvulsant agent, divalproex (DVPX), in alcohol-dependent individuals. Alcohol use (Timeline Follow Back), impulsivity (Barratt Impulsivity Scale), irritability and aggression (Buss-Durkee Hostility Index; and Anger, Irritability, Aggression Scale) were measured at baseline and throughout the 12-week treatment period. Drinking decreased significantly in both the placebo and the DVPX-treated groups. In the DVPX group, a significantly smaller percentage of individuals relapsed to heavy drinking, but there were no significant differences in other alcohol-related outcomes. There were significantly greater decreases in irritability in the DVPX-treated group and a trend towards greater decreases on measures of lability and verbal assault. There were no significant between-group differences on measures of impulsivity. While DVPX did not have a robust effect on alcohol-related outcomes, it did have modest impact on a measure of irritability. This is consistent with the findings of other investigators exploring the use of DVPX in schizophrenia, personality disorder and a number of other psychiatric disorders.

Longevity genes in the nematode Caenorhabditis elegans also mediate increased resistance to stress and prevent disease

More than 40 single-gene mutants in Caenorhabditis elegans have been demonstrated to lead to increased lifespan (a rigorous, operational test for being a gerontogene) of 20% or more; these are referred to collectively as 'Age' mutants. Age mutants must change key functions that are rate-limiting determinants of longevity; moreover, important genes can be identified independently of prior hypotheses as to actual mode of gene action in extending longevity and/or 'slowing' of ageing. These Age mutants define as many as nine (possibly) distinct pathways and/or modes of action, as defined by primary phenotype. Each of three well-studied mutants (age-1, clk-1, and spe-26) alters age-specific mortality rates in a fashion unique to itself. In age-1 mutants, the decreases in mortality rates are quite dramatic, with an almost tenfold drop in mortality throughout most of life. All Age mutants (so far without exception) increase the ability of the worm to respond to several (but not all) stresses, including heat, UV, and reactive oxidants. We have used directed strategies as well as random mutagenesis to identify novel genes that increase the worm's ability to resist stress. Two genes (daf-16 and old-1) are epistatic to the long-life phenotype of most mutants and also yield over-expression strains that are stress-resistant and long-lived. We have also used a variety of approaches to determine what transcriptional alterations are associated with increased longevity (and with ageing itself), including whole-genome expression studies using microarrays and GFP reporter constructs. We suggest that the role of the Age genes in both longevity and stress resistance indicates that a major evolutionary determinant of longevity is the ability to respond to stress. In mammals, both dietary restriction and hormesis are phenomena in which the endogenous level of resistance to stress has been upregulated; both of these interventions extend longevity, suggesting possible evolutionary conservation.

Evaluation in an anaesthetic simulator of a prototype of a new drug administration system designed to reduce error

Ten anaesthetists were observed while providing anaesthesia for two simulated surgical procedures, twice using conventional methods and twice using a prototype of a new drug administration system designed to reduce error. Aspects of each method were rated by users on 10-cm visual analogue scales (10 being best) and comments were invited. Median safety scores were 7.7 cm (range 4.3-8.9) for the new system and 4.6 cm (1.3-8.2) for conventional methods (p = 0.009). The new system was compared favourably with conventional methods in respect of safety (p = 0.005), clinical acceptability (p = 0.008), organisation and layout (p = 0.047), and acceptability for use on patients (p = 0.005). The new system saved time in the preparation of drugs both before anaesthesia (105 vs. 346 s; p < 0.001) and during anaesthesia (20 vs. 104 s; p < 0.001). Comments facilitated development of the system and the evaluation endorsed proceeding to a clinical trial.

Direct measurements of colloidal friction coefficients

The time-independent hydrodynamic forces operating between two hard spheres were studied as a function of the interparticle separation r. Two colloids were positioned a distance r apart using a dual-beam optical tweezer similar to that described by Meiners and Quake [Phys. Rev. Lett. 82, 2211 (1999)]. Brownian fluctuations in the positions of the two spheres were followed by recording the intensity of forward scattered laser light. The two particles move cooperatively as a result of hydrodynamic forces. The strength of the correlation increased strongly with decreasing separation r. We show that the temporal and spatial correlations in the particle displacements are determined by the distance dependence of the pair friction tensor xi. The distance and geometry dependence of the measured friction tensor is found to be in excellent agreement with the predictions of low-Reynolds number calculations.

Relationship between increased longevity and stress resistance as assessed through gerontogene mutations in Caenorhabditis elegans

We review the status of the hypothesis that interventions that increase the resistance to stress offer the potential for effective life prolongation and increased health. The work focuses on research in the nematode worm Caenorhabditis elegans and describes both published and unpublished results consistent with this hypothesis. Correlation between stress resistance and longevity among many gerontogene mutants is provided.

Utility of a new assay for carbohydrate-deficient transferrin (Biorad %CDT TIA) to monitor abstinence during a treatment outcome study

BACKGROUND

The ability to reliably detect heavy alcohol use is important in both clinical and research populations. The current study evaluates the utility of the newest method of measuring carbohydrate deficient transferrin (CDT) in monitoring the abstinence during a treatment outcome study.

METHODS

Blood from 40 alcohol dependent individuals was obtained at baseline and at weeks 4, 8, and 12 of treatment. Differences in percent of baseline GGT and %CDT levels were analyzed in people who remained abstinent throughout treatment (abstainers) and in those who consumed alcohol during treatment (drinkers).

RESULTS

There was a significant decrease in the percent of baseline %CDT levels in the subjects who abstained at week 4 and a trend at weeks 8 and 12. Conversely, there were no significant differences in percent of baseline GGT levels between drinkers and abstainers at any time point.

CONCLUSIONS

Although small in nature, this study provides preliminary evidence for the use of the relatively new Biorad %CDT assay to monitor drinking status during treatment outcome studies. This study is also consistent with previously reported findings that GGT appears to be less sensitive than %CDT in detecting the consumption of alcohol. A larger trial focusing on sex differences in the utility of % CDT to monitor outcome would be of interest.

Divalproex loading in the treatment of cocaine dependence

The current pilot project was designed to evaluate the safety and tolerability of a loading dose of divalproex (DVPX) in subjects with cocaine dependence. Seventeen cocaine-dependent subjects were enrolled in an eight-week, open-label trial of 20 mg/kg/day DVPX. Subjects were seen weekly and urine drug screens were obtained at each visit. Over the eight-week trial, craving intensity and frequency as well as reported time using cocaine decreased significantly. Retention in the current study was 79% at week four and 50% at week eight. The medication and dosing strategy was well tolerated. This pilot study indicates that DVPX loading is well tolerated and may be efficacious in the treatment of cocaine dependence. A placebo-controlled trial would be of interest.

The use of permanent pacemakers in the detection of cardiac arrhythmias

AIMS

To compare pacemaker telemetry with simultaneous Holter recordings in the diagnosis of atrial fibrillation and to evaluate the STOP-AF study telemetry criteria for the presence of atrial fibrillation.

METHODS AND RESULTS

18 consecutive patients enrolled in the STOP-AF study had simultaneous 24 h Holter recordings and down-loaded pacemaker telemetry. There was good agreement on heart rate, but the STOP-AF pacemaker criteria achieved only 57% sensitivity with 64% specificity for the presence of atrial fibrillation on Holter recording over 24 h. False-positives appeared to result from far-field sensing while false-negatives occurred with very short episodes of atrial fibrillation. The pacemaker's antitachycardia responses were not specific for the presence of atrial fibrillation.

CONCLUSION

Pacemaker telemetry is a potentially important source of data on cardiac arrhythmias. Further studies are required to define the limitations of these data in specific devices before they can be interpreted with confidence.

Non-disabled cases in a national survey

BACKGROUND

Lifetime and 12-month prevalence estimates of mental disorders consistently reported in large-scale community surveys have met with deserved scepticism. A crucial variable is the extent to which people who are considered cases are also disabled by their symptoms. In a national population survey, we hypothesized that an administratively significant proportion of persons with anxiety or depressive disorders according to ICD-10 and DSM-IV would report no disability.

METHODS

Interviews were sought on a nationally representative sample of people aged 18 and over across Australia. The Composite International Diagnostic Interview on laptop (CIDI-A) was used by professional survey interviewers to identify persons meeting ICD-10 or DSM-IV criteria for anxiety or depressive disorders in the previous 4 weeks, together with self-reported data on associated disability and medical consultations for the same period.

RESULTS

In an achieved sample of 10,641 persons (response rate = 78%), no disability in daily life was reported by 28% of persons with an anxiety disorder and 15% with a depressive disorder by ICD-10 criteria; and by 20.4% and 13.9% respectively by DSM-IV. Non-disabled respondents had lower scores on two measures of psychological distress and markedly lower rates for having consulted a doctor for their symptoms.

CONCLUSION

The ICD-10 and DSM-IV criteria for anxiety and depressive disorders, when applied to the information on symptoms elicited by the CIDI-A, inadequately discriminate between people who are and are not disabled by their symptoms. There may be a group of highly symptomatic people in the general population who tolerate their symptoms and are not disabled by them.

Enhancing wire-composite bond strength of bonded retainers with wire surface treatment

Bonded orthodontic retainers with wires embedded in composite resin are commonly used for orthodontic retention. The purpose of this study was to test, in vitro, various wire surface treatments to determine the optimal method of enhancing the wire-composite bond strength. Coaxial wires and stainless steel wires with different surface treatments were bonded to bovine enamel and then pulled along their long axes with an Instron universal testing machine. Wire surface treatments included placing a right-angle bend in the wire, microetching the wire, and treating the wire with adhesion promoters; combinations of treatments were also examined. The results demonstrated a 24-fold increase in the wire-composite bond strength of wire that was microetched (sandblasted), compared with that of untreated straight wire. The difference between the amount of force required to break the bond produced by microetching alone (246.1 +/- 46.0 MPa) and that required for the bonds produced by the retentive bend (87.8 +/- 16.3 MPa), the adhesion promoters (silane, 11.0 +/- 3.1 MPa; Metal Primer, 28.5 +/- 15.8 MPa), or for any combination of surface treatments, was statistically significant. Microetching a stainless steel wire produced a higher wire-composite bond strength than that obtained from a coaxial wire (113.5 +/- 27.5 MPa). The results of this study indicate that microetching or sandblasting a stainless steel wire significantly increases the strength of the wire-composite bond.

The effects of endurance training and exhaustive exercise on mitochondrial enzymes in tissues of the rat (Rattus norvegicus)

The aim of the present study was to ascertain the effects of training and exhaustive exercise on mitochondrial capacities to oxidize pyruvate, 2-oxoglutarate, palmitoylcarnitine, succinate and ferrocytochrome c in various tissues of the rat. Endurance capacity was significantly increased (P<0.01) by an endurance training program over a period of 5-6 weeks. The average run time to exhaustion was 214.2+/-23.8 min for trained rats in comparison with 54.5+/-11.7 min for their untrained counterparts. Oxidative capacities were reduced in liver (P<0.05) and brown adipose tissue (P<0.05) as a result of endurance training. On the contrary, the oxidative capacity of skeletal muscle was slightly increased and that of heart almost unaffected except for the oxidation of palmitoylcarnitine, which was significantly reduced (P<0.05) as a result of training.

Jun NH2-terminal kinase phosphorylation of p53 on Thr-81 is important for p53 stabilization and transcriptional activities in response to stress

The p53 tumor suppressor protein plays a key role in the regulation of stress-mediated growth arrest and apoptosis. Stress-induced phosphorylation of p53 tightly regulates its stability and transcriptional activities. Mass spectrometry analysis of p53 phosphorylated in 293T cells by active Jun NH2-terminal kinase (JNK) identified T81 as the JNK phosphorylation site. JNK phosphorylated p53 at T81 in response to DNA damage and stress-inducing agents, as determined by phospho-specific antibodies to T81. Unlike wild-type p53, in response to JNK stimuli p53 mutated on T81 (T81A) did not exhibit increased expression or concomitant activation of transcriptional activity, growth inhibition, and apoptosis. Forced expression of MKP5, a JNK phosphatase, in JNK kinase-expressing cells decreased T81 phosphorylation while reducing p53 transcriptional activity and p53-mediated apoptosis. Similarly transfection of antisense JNK 1 and -2 decreased T81 phosphorylation in response to UV irradiation. More than 180 human tumors have been reported to contain p53 with mutations within the region that encompasses T81 and the JNK binding site (amino acids 81 to 116). Our studies identify an additional mechanism for the regulation of p53 stability and functional activities in response to stress.

The sequence of the human genome

A 2.91-billion base pair (bp) consensus sequence of the euchromatic portion of the human genome was generated by the whole-genome shotgun sequencing method. The 14.8-billion bp DNA sequence was generated over 9 months from 27,271,853 high-quality sequence reads (5.11-fold coverage of the genome) from both ends of plasmid clones made from the DNA of five individuals. Two assembly strategies-a whole-genome assembly and a regional chromosome assembly-were used, each combining sequence data from Celera and the publicly funded genome effort. The public data were shredded into 550-bp segments to create a 2.9-fold coverage of those genome regions that had been sequenced, without including biases inherent in the cloning and assembly procedure used by the publicly funded group. This brought the effective coverage in the assemblies to eightfold, reducing the number and size of gaps in the final assembly over what would be obtained with 5.11-fold coverage. The two assembly strategies yielded very similar results that largely agree with independent mapping data. The assemblies effectively cover the euchromatic regions of the human chromosomes. More than 90% of the genome is in scaffold assemblies of 100,000 bp or more, and 25% of the genome is in scaffolds of 10 million bp or larger. Analysis of the genome sequence revealed 26,588 protein-encoding transcripts for which there was strong corroborating evidence and an additional approximately 12,000 computationally derived genes with mouse matches or other weak supporting evidence. Although gene-dense clusters are obvious, almost half the genes are dispersed in low G+C sequence separated by large tracts of apparently noncoding sequence. Only 1.1% of the genome is spanned by exons, whereas 24% is in introns, with 75% of the genome being intergenic DNA. Duplications of segmental blocks, ranging in size up to chromosomal lengths, are abundant throughout the genome and reveal a complex evolutionary history. Comparative genomic analysis indicates vertebrate expansions of genes associated with neuronal function, with tissue-specific developmental regulation, and with the hemostasis and immune systems. DNA sequence comparisons between the consensus sequence and publicly funded genome data provided locations of 2.1 million single-nucleotide polymorphisms (SNPs). A random pair of human haploid genomes differed at a rate of 1 bp per 1250 on average, but there was marked heterogeneity in the level of polymorphism across the genome. Less than 1% of all SNPs resulted in variation in proteins, but the task of determining which SNPs have functional consequences remains an open challenge.

Prevalence, comorbidity, disability and service utilisation. Overview of the Australian National Mental Health Survey

BACKGROUND

Health planning should be based on data about prevalence, disability and services used.

AIMS

To determine the prevalence of ICD-10 disorders and associated comorbidity, disability and service utilisation.

METHOD

We surveyed a national probability sample of Australian households using the Composite International Diagnostic Interview and other measures.

RESULTS

The sample size was 10 641 adults, response rate 78%. Close to 23% reported at least one disorder in the past 12 months and 14% a current disorder. Comorbidity was associated with disability and service use. Only 35% of people with a mental disorder in the 12 months prior to the survey had consulted for a mental problem during that year, and most had seen a general practitioner. Only half of those who were disabled or had multiple comorbidity had consulted and of those who had not, more than half said they did not need treatment.

CONCLUSIONS

The high rate of not consulting among those with disability and comorbidity is an important public health problem. As Australia has a universal health insurance scheme, the barriers to effective care must be patient knowledge and physician competence.

Aerodigestive injuries of the neck

Cervical aerodigestive trauma is rare and most centers have a limited experience with its management. The purpose of this review was to study the epidemiology, diagnosis, and problems related to the early evaluation and management of these injuries. This was a retrospective study based on trauma registry and on chart, operative, radiological, and endoscopic reports. There were 1560 admissions with blunt or penetrating trauma to the neck. The overall incidence of aerodigestive trauma was 4.9 per cent (10.2% for gunshot wounds, 4.6% for stab wounds, and 1.2% for blunt trauma). All patients with aerodigestive trauma had suspicious signs or symptoms on admission. The most common life-threatening problem in the emergency room and directly related to the aerodigestive trauma was airway compromise. Twenty-nine per cent of patients with laryngotracheal trauma required an emergency room airway establishment because of threatened airway loss. Although rapid sequence induction was successful in the majority of cases, in 11.9 per cent there was loss of airway and a cricothyroidotomy was necessary. Overall, 9 per cent of cases with aerodigestive injuries were successfully treated nonoperatively. Thirty-six per cent of patients with laryngotracheal trauma and surgical repair were successfully treated without a protective tracheostomy. There was no mortality due to the aerodigestive injuries. Cervical aerodigestive trauma is rare. In conclusion, all patients with significant aerodigestive injuries requiring treatment had suspicious signs and symptoms. Airway compromise was a common problem in the emergency room. Loss of airway after rapid sequence induction is a potentially lethal complication and the trauma team should be ready for a surgical airway. Repair of laryngotracheal injuries without a protective tracheostomy is safe in selected cases.