Comparative proteomics reveals evidence for evolutionary diversification of rodent seminal fluid and its functional significance in sperm competition

During insemination, males of internally fertilizing species transfer a complex array of seminal fluid proteins to the female reproductive tract. These proteins can have profound effects on female reproductive physiology and behavior and are thought to mediate postcopulatory sexual selection and intersexual conflict. Such selection may cause seminal fluid to evolve rapidly, with potentially important consequences for speciation. Here we investigate the evolution of seminal fluid proteins in a major mammalian radiation, the muroid rodents, by quantifying diversity in seminal fluid proteome composition for the first time across a broad range of closely related species. Using comparative proteomics techniques to identify and cross-match proteins, we demonstrate that rodent seminal fluid is highly diverse at the level of both proteomes and individual proteins. The striking interspecific heterogeneity in seminal fluid composition revealed by our survey far exceeds that seen in a second proteome of comparable complexity, skeletal muscle, indicating that the complement of proteins expressed in seminal fluid may be subject to rapid diversification. We further show that orthologous seminal fluid proteins exhibit substantial interspecific variation in molecular mass. Because this variation cannot be attributed to differential glycosylation or radical differences in termination sites, it is strongly suggestive of rapid amino acid divergence. Sperm competition is implicated in generating such divergence for at least one major seminal fluid protein in our study, SVS II, which is responsible for copulatory plug formation via transglutaminase-catalyzed cross-linking after insemination. We show that the molecular mass of SVS II is positively correlated with relative testis size across species, which could be explained by selection for an increased number of cross-linking sites involved in the formation of the copulatory plug under sperm competition.

Positional proteomics: preparation of amino-terminal peptides as a strategy for proteome simplification and characterization

We describe a protocol for selective extraction of the amino (N)-terminal-most peptide of a protein or a mixture of proteins after proteolysis. The first stage of the protocol blocks the free amino groups alpha and epsilon (the latter being lysyl residues) on the intact proteins by acetylation. In the second stage, proteolysis of the acetylated proteins yields a mixture of N-terminally acetylated (true N-terminal) and non-acetylated (internal and carboxy-terminal) peptides. Affinity capture of peptides bearing free amino groups using an immobilized amine-reactive reagent removes internal peptides from the mixture. The unbound fraction is highly enriched in N-terminal peptides, which can be analyzed without further treatment. This method is compatible with a range of proteolytic enzymes and fragmentation methods, and should take 2 d to complete. The N-terminal peptides can then be analyzed by mass spectrometry. This low cost, rapid method is readily adopted using off the shelf reagents.

Predictors of depressive symptoms in primary caregivers of young children with or at risk for developmental delay

BACKGROUND

Despite extensive research with families raising children with or at risk for developmental delay (DD), it is not clear whether primary caregivers of these children are at increased risk for depressive symptoms. Discrepant findings in the literature may be owing to heterogeneity of child problems. More research is needed on child, parent and family variables that may increase risk for, or resilience to, caregiver depressive symptoms. Some studies have found that parental resources (e.g. social support and coping strategies) may buffer the effects of parental distress, while other studies have highlighted the role of parental self-efficacy.

METHODS

We examined Beck Depression Inventory (BDI) scores in 178 primary caregivers (mainly biological mothers) who had 2-year-old children with or at risk for DD owing to: (a) low birthweight, prematurity or multiple birth (n = 58), (b) other known reasons (e.g. Down syndrome, spina bifida) (n = 67), or (c) unknown reasons (n = 69).

RESULTS

We found that 20% (n = 35) of the caregivers scored above the BDI clinical cut-off for depression. Analysis of variance revealed that caregivers with elevated BDI scores had higher child behaviour problem and escape-avoidance coping scores, and lower social support and parent self-efficacy, compared with caregivers without depressive symptoms. Caregivers with children who had DD for unknown reasons had higher BDI scores than caregivers of the other two groups of children. Regression analyses showed that child behaviour problems, escape-avoidance coping strategies and social support predicted caregiver BDI scores, but caregiver self-efficacy only did so when entered independently of social support. Only social support mediated and (marginally) moderated the relationship between child behaviour problems and caregiver depressive symptoms.

CONCLUSIONS

These findings suggest that early intervention programmes should carefully consider the interaction of child characteristics (e.g. Diagnosis and behaviour problems), caregiver resources (e.g. coping strategies and social support), and parental mental health and mood when planning and tailoring services for families of children with or at risk for DD.

Chemical ripeners increase early season sugar content in a range of sugarcane varieties

Ripening in sugarcane refers to an increase in sugar content on a fresh weight basis before commercial harvest. Certain chemicals are applied to cane in commercial fields in some countries to accelerate ripening and improve profitability of sugar production. However, responses have usually been reported to be variety and environment specific. We examined changes in the sucrose content in the juice extracted from 43 Australian sugarcane (Saccharum spp. hybrid) varieties in response to 4 ripener treatments in the Burdekin region in northern Queensland over 2 years. The 4 treatments applied were ethephon (as Ethrel®) + fluazifop-P butyl (as Fusilade®), Fusilade® alone, glyphosate (as Weedmaster® Duo), and haloxyfop-R methyl (as Verdict®). These treatments were applied in March–April each year and compared with an untreated control. Of particular interest was whether economic responses are possible for Australian varieties harvested in the May and June period when sugar content in cane is usually low. Increases in sucrose (measured by pol) levels in cane juice were observed after combined application of Ethrel + Fusilade (E+F) and after application of glyphosate, although the result for the latter varied between years. These results suggest that opportunities exist in the Australian industry to improve the profitability of early-harvested sugarcane crops, but further research is required to quantify effects on cane yield and responses in diverse environments.

Patient satisfaction in radiation oncology

As part of a quality improvement exercise at the Perth Radiation Oncology Centre, a survey was undertaken to ascertain the current level of patient satisfaction with the information they were receiving from their treating radiation oncologist. In addition, the effect of radiation on patients' anxiety levels was investigated. Two questionnaires were given to patients having radical radiotherapy for malignancy. The first questionnaire consisted of the Information Satisfaction Questionnaire and the State Trait Anxiety Index. It was given to patients before the commencement of their course of radiotherapy. The second questionnaire consisted of the State Trait Anxiety Index and was given at the completion of their radiotherapy. A total of 120 patients completed both the questionnaires. The majority of patients were satisfied/very satisfied with the explanation of their illness and radiation toxicities. Fewer patients were satisfied with the explanation of lifestyle (e.g. diet, exercise, smoking) and practical issues such as parking and treatment costs. The patients showed a statistically significant reduction in both their State and Trait Anxiety scores following radiotherapy. Following this study, we have developed new information booklets addressing lifestyle and practical issues, which were not being adequately addressed as shown in this study. Our next study will assess the effect of these new information booklets.

Investigation of global developmental delay

The investigation of global developmental delay in preschool children varies between centres and between paediatricians. Following a literature search and review of the evidence base, guidelines were developed to assist in the assessment and management of such children presenting to secondary level services. Evidence supporting the use of genetic and biochemical investigations on a screening basis was found, but there was no evidence to support the use of metabolic investigations or neuroimaging in the absence of other positive findings on history or examination. Detailed history and examination are paramount in the assessment of children with global developmental delay. Investigations can be a useful adjunct in determining aetiology. Evidence based guidelines have been developed to assist doctors in the selection of appropriate investigations for this group of children.

The DNA sequence and biological annotation of human chromosome 1

The reference sequence for each human chromosome provides the framework for understanding genome function, variation and evolution. Here we report the finished sequence and biological annotation of human chromosome 1. Chromosome 1 is gene-dense, with 3,141 genes and 991 pseudogenes, and many coding sequences overlap. Rearrangements and mutations of chromosome 1 are prevalent in cancer and many other diseases. Patterns of sequence variation reveal signals of recent selection in specific genes that may contribute to human fitness, and also in regions where no function is evident. Fine-scale recombination occurs in hotspots of varying intensity along the sequence, and is enriched near genes. These and other studies of human biology and disease encoded within chromosome 1 are made possible with the highly accurate annotated sequence, as part of the completed set of chromosome sequences that comprise the reference human genome.

Positional proteomics: selective recovery and analysis of N-terminal proteolytic peptides

Bottom-up proteomics is the analysis of peptides derived from single proteins or protein mixtures, and because each protein generates tens of peptides, there is scope for controlled reduction in complexity. We report here a new strategy for selective isolation of the N-terminal peptides of a protein mixture, yielding positionally defined peptides. The method is tolerant of several fragmentation methods, and the databases that must be searched are substantially less complex.

Ethical and legal issues in caring for asylum seekers and refugees in the UK

Inward migration to the UK remains topical and controversial as numbers continue to increase. Many immigrants have specific health care needs and may shoulder a large burden of infectious disease. Imposition of legal constraints can have a huge impact on the medical care afforded to immigrants. Currently UK policy is to treat, free of charge and with NHS resources, those who fulfil specific criteria. However an increasing number are being asked to pay for their treatment. Many health care professionals are confused as to current legal restrictions and require guidance on the associated ethical issues. We concentrate on provision of care to HIV positive individuals and use cases to illustrate some of the issues. However these issues are equally pertinent to practitioners in all branches of medicine.

How much explanation is enough? A study of parent requests for information and physician responses

OBJECTIVE

To examine the relationship between doctor-parent communication patterns and parents' perceptions that they were listened to by the doctor.

DESIGN

Cross-sectional, clinic-based survey. Before the visit, parents were asked about the strength of their desires/preferences for being listened to; after the visit, they were asked if their desires were fulfilled and to rate their satisfaction with care. Encounters were audiotaped, transcribed, and coded for parent requests for information and action and physician responses to those requests. Coding was performed using an adapted version of the Taxonomy of Requests by Patients (TORP). Physician responses to parental requests for information were coded as brief, moderate, or prolonged fulfillment or as partially fulfilled, ignored, or denied.

SETTING

Two private pediatric practices, 1 community based and 1 university based.

PARTICIPANTS

Ten of 13 eligible physicians (participation rate, 77%) and 306 of 356 eligible parents (participation rate, 86%) who sought care for their children's respiratory illnesses. Parents were invited to participate if they spoke and read English and if their child was 2-10 years old, had a chief complaint of cold symptoms, and was seeing one of the participating physicians. Complete data were obtained for 287 doctor-parent encounters (94%).

RESULTS

Before the visit, 74% of parents reported that they considered it necessary for the physician to listen to their ideas about their child's illness. Among these parents, 62% (n = 130) reported after the visit that the physician had listened to their ideas. As the proportion of moderate-length responses to parent requests for information increased, parents were significantly more likely to report being listened to (P <.05). Multivariate results indicated a 59% probability of parents reporting that they were listened to when given moderate-length responses, 45% when given brief responses, 39% when given prolonged responses, and 12% when requests for information were only partially fulfilled, ignored, or denied. The length of response to parent requests for information was not related to overall parent satisfaction.

CONCLUSIONS

Parents who received moderate-length answers to their questions were most likely to report that they were listened to. Although it is assumed that lengthier, in-depth explanations result in higher satisfaction, this study suggests that more doctor talk does not necessarily constitute better communication.

Parent expectations for antibiotics, physician-parent communication, and satisfaction

OBJECTIVES

To explore how parents communicate their preferences for antibiotics to their child's physician and to examine whether physicians can communicate why antibiotics are not being prescribed in a way that maintains satisfaction with the visit.

DESIGN

Previsit survey of parents, audiotaping of the study encounters, and a postvisit survey of parents and physicians.

SETTING

Two private pediatric practices.

PARTICIPANTS

Ten physicians (response rate = 77%) and a consecutive sample of 295 eligible parents (response rate = 86%) who attended acute care visits for their children between October 1996 and March 1997.

MAIN OUTCOME MEASURES

Physician-perceived pressure to prescribe antibiotics and parental visit-specific satisfaction.

RESULTS

Fifty percent of parents expressed a previsit expectation for antibiotics. Among these parents, only 1% made a direct verbal request for them. Even when no direct requests for antibiotics were made, physicians still perceived an expectation for antibiotics 34% of the time. Among parents who did not receive expected antibiotics, those offered a contingency plan from the physician (i.e., the possibility of receiving antibiotics in the future if their child did not get better) had a higher mean satisfaction score than parents not receiving a contingency plan (76 vs. 58.9; P<.05).

CONCLUSION

Physicians should consider providing a contingency plan to parents who expect antibiotics for their children when there is no clinical indication. Further study is needed to determine how parents indirectly communicate their desire for antibiotics and what additional communication techniques physicians can use to resist the overprescribing of antibiotics.

The meaning of life: animism in the classificatory skills of older adults

Seventy-five participants aged from their teens to their seventies were measured on a battery of measures of personality, lifestyle, intelligence, and educational background. These measures were gauged against performance on a measure of animism, in which participants judged twenty-three items (4 alive, 19 non-living) as living or non-living. Although animism errors increased with age, all groups displayed animism errors, thereby contradicting Piaget (1965). Performance is partially explained by fluid intelligence level, but is more plausibly ascribed to progressive loss of what is essentially peripheral information to non-academic people.

Low-density lipoprotein (LDL)-induced monocyte-endothelial cell adhesion, soluble cell adhesion molecules, and autoantibodies to oxidized-LDL in chronic renal failure patients on dialysis therapy

Premature atherosclerosis is a major cause of morbidity and mortality in chronic renal failure patients undergoing dialysis. In this study, we compared autoantibodies to oxidized low-density lipoprotein (OX-LDL), soluble cell adhesion molecules (CAMs), and the effect of both LDL and OX-LDL on monocyte endothelial cell adhesion in chronic renal failure patients on hemodialysis (HD, n = 16) and peritoneal dialysis (PD, n = 17) compared with matched healthy control subjects (C, n = 17). In addition, we studied the effect of supplementation with RRR-alpha-tocopherol (AT) 800 IU/d for 12 weeks on the above measures. LDL and OX-LDL induced adhesion of U937 cells to cultured endothelium, soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble intracellular adhesion molecule-1 (sICAM-1), and soluble E-selectin (sE-selectin); autoantibodies to OX-LDL and markers of lipid peroxidation were determined before and after AT supplementation. Native LDL from PD patients induced greater monocyte-endothelial cell adhesion than LDL from C subjects (43.8% +/- 17.0% v25.3% +/- 17.7%, respectively, P = .0028). OX-LDL from chronic renal failure patients on both PD and HD stimulated greater adhesion than OX-LDL from the C subjects (68.0% +/- 18.5% and 57.6% +/- 15.1% v 40.9% +/- 17.3%, respectively, P < .01); OX-LDL from PD patients induced greater adhesion than that from HD patients (P < .01). Plasma methylglyoxal levels were significantly increased in both HD and PD groups, with higher levels in the HD group. Chronic renal failure patients on HD and PD also had higher levels of plasma sVCAM-1 and sE-selectin than C subjects (P < .01), indicating endothelial activation. Titers of autoantibodies to OX-LDL were not elevated in renal failure patients. Supplementation with AT 800 IU/d for 12 weeks, while resulting in significant enrichment with AT in LDL, did not have a significant effect on any of the parameters studied. This study makes the novel observation that the LDL of chronic renal failure patients on HD and PD appears to be potentially more atherogenic, since it induces greater monocyte-endothelial cell adhesion.

Management of myocardial infarction in the very elderly--impact of clinical effectiveness on practice

The presentation of myocardial infarction in the elderly is often atypical and there is therefore a broad range of clinical presentations where this diagnosis should be actively considered and the appropriate investigations arranged. The early use of aspirin and thrombolytic therapy has revolutionised management and efforts should be made to employ these interventions wherever possible. We present the results of an audit showing how the introduction of local guidelines improved the early management of myocardial infarction in the elderly. We also found that in this group of patients cardiac enzyme assays were more useful in establishing the diagnosis than the electrocardiogram.

Cardiac septal and valvular dysmorphogenesis in mice heterozygous for mutations in the homeobox gene Nkx2-5

Heterozygous mutations in the cardiac homeobox gene, NKX2-5, underlie familial cases of atrial septal defect (ASD) with severe atrioventricular conduction block. In this study, mice heterozygous for Nkx2-5-null alleles were assessed for analogous defects. Although ASD occurred only rarely, atrial septal dysmorphogenesis was evident as increased frequencies of patent foramen ovale and septal aneurysm, and decreased length of the septum primum flap valve. These parameters were compounded by genetic background effects, and in the 129/Sv strain, septal dysmorphogenesis bordered on ASD in 17% of Nkx2-5 heterozygotes. In a proportion of neonatal heterozygotes, as well as in adults with ASD, we found that the size of the foramen ovale was significantly enlarged and altered in shape, potentially exposing the normally thin septum primum to excessive hemodynamic forces. Therefore, defective morphogenesis of the septum secundum may be one contributing factor in the generation of patent foramen ovale, septal aneurysm, and certain ASDs. Mild prolongation of P-R interval in females and an increased frequency of stenotic bicuspid aortic valves were also features of the Nkx2-5 heterozygous phenotype. Our data demonstrate that the complex effects of Nkx2-5 haploinsufficiency in mice are weaker but convergent with those in humans. As in the mouse, the phenotype of human NKX2-5 mutations may be modulated by interacting alleles.

Elderly drivers and their accidents: the Aging Driver Questionnaire

The Manchester Driver Behavior Questionnaire (DBQ) was included as part of a questionnaire survey of 1989 drivers aged 50 or over. Previous research has differentiated three main types of aberrant driver behavior: errors, lapses and violations. Each of these has different psychological origins, and different implications for road safety interventions [Reason et al., 1990. Ergonomics 33, 1315-1312]. It has also been shown that, using a full age-range sample of drivers, reported violations were statistically associated with accident involvement, whereas errors and lapses were not [Parker et al., 1995a. Ergonomics 38, 1036-1048; Parker et al., 1995b. Accident Analysis and Prevention 27, 571-581]. Although factor analysis of the DBQ responses of this sample produced five factors, the original three-way distinction was preserved. However the pattern of relationships between factor scores and accident involvement was different. Relatively high scores on the error factor and the lapse factor were predictive of involvement in an active accident, while passive accident involvement was associated with high scores on the lapse factor.

The effect of increasing visual horizons on stereotypic weaving: implications for the social housing of stabled horses

Stabled horses commonly perform stereotypic patterns of weaving, where the horse shifts its weight from side to side often swinging its head. Ten warm-blood types, of which five were known to reliably weave, were housed in similar 12x12 ft wooden loose boxes in a single stable block surrounding a courtyard. Each horse was exposed to each of five stable designs. These were: the conventional front top-half of the door open only with a view of the stable courtyard (F); front half-door open and a similar half-door open at the back of the stable with a view to the surrounding fields (FB); back open only (B); front and one-side panel open with a view into the adjacent stable (FS); and front, back and both sides open (All4). During observation days, horses were brought in from the field at 0830 h, fed concentrate at 0930 h, fed haylage at 1005 h and turned out at 1600 h. Behaviour was recorded from 0900 to 1040 h, 1200 to 1300 h and 1500 to 1600 h. Weaving was most common prior to feeding in the morning and prior to putting out to pasture in the afternoon. There was a significant effect of stable design on weaving, with less weaving in the FS and All4 designs than the F treatment. There was also a significant effect of stable design on repetitive nodding, though in this case, FB, B, FS and All4 designs each reduced nodding compared with the F treatment. The effect of stable design can be explained in a number of ways. Firstly, it could be the novelty of the environmental change, though there was no evidence in this study of an increase in stereotypy with prolonged exposure to the new stable designs. Secondly, opening windows may increase opportunities for environmental interaction, and the expression of new activities may compete with stereotypic behaviour for the horse's time. Thirdly, the open windows may allow expression of specific activities such as environmental monitoring or social interaction that are denied by the conventional stable.

Identification and analysis of bacterial protein secretion inhibitors utilizing a SecA-LacZ reporter fusion system

Protein secretion is an essential process for bacterial growth, yet there are few if any antimicrobial agents which inhibit secretion. An in vivo, high-throughput screen to detect secretion inhibitors was developed based on the translational autoregulation of one of the central protein components, SecA. The assay makes use of a SecA-LacZ fusion reporter construct in Escherichia coli which is induced when secretion is perturbed. Several compounds, including two natural product extracts, which had the ability to induce the reporter fusion were identified and the MICs of these compounds for Staphylococcus aureus strain MN8 were found to be < or =128 microg/ml. Enzyme-linked immunosorbent assay, Western blotting, and immunoprecipitation techniques were used to analyze the affects of these compounds on protein secretion. Six representative compounds presented here appear to be bona fide secretion inhibitors but were found to have deleterious effects on membranes. It was concluded that, while the method described here for identifying inhibitors of secretion is valid, screens such as this, which are directed against the membrane-bound portion of a pathway, may preferentially identify compounds which affect membrane integrity.

A 6-Mb high-resolution physical and transcription map encompassing the hereditary prostate cancer 1 (HPC1) region

Several hereditary disease loci have been genetically mapped to the chromosome 1q24-q31 interval, including the hereditary prostate cancer 1 (HPC1) locus. Here, we report the construction of a 20-Mb yeast artificial chromosome contig and a high-resolution 6-Mb sequence-ready bacterial artificial chromosome (BAC)/P1-derived artificial chromosome (PAC) contig of 1q25 by sequence and computational analysis, STS content mapping, and chromosome walking. One hundred thirty-six new STSs, including 10 novel simple sequence repeat polymorphisms that are being used for genetic refinement of multiple disease loci, have been generated from this contig and are shown to map to the 1q25 interval. The integrity of the 6-Mb BAC/PAC contig has been confirmed by restriction fingerprinting, and this contig is being used as a template for human chromosome 1 genome sequencing. A transcription mapping effort has resulted in the precise localization of 18 known genes and 31 ESTs by database searching, exon trapping, direct cDNA hybridization, and sample sequencing of BACs from the 1q25 contig. An additional 11 known genes and ESTs have been placed within the larger 1q24-q31 interval. These transcription units represent candidate genes for multiple hereditary diseases, including HPC1.

High level expression of differentially localized BAG-1 isoforms in some oestrogen receptor-positive human breast cancers

Sensitivity to oestrogens and apoptosis are critical determinants of the development and progression of breast cancer and reflect closely linked pathways in breast epithelial cells. For example, induction of BCL-2 oncoprotein expression by oestrogen contributes to suppression of apoptosis and BCL-2 and oestrogen receptor (ER) are frequently co-expressed in tumours. BAG-1/HAP is a multifunctional protein which complexes with BCL-2 and steroid hormone receptors (including the ER), and can suppress apoptosis and influence steroid hormone-dependent transcription. Therefore, analysis of expression of BAG-1 in human breast cancer is of considerable interest. BAG-1 was readily detected by immunostaining in normal breast epithelial cells and most ER-positive tumours, but was undetectable or weakly expressed in ER-negative tumours. BAG-1 positive cells showed a predominantly cytoplasmic or cytoplasmic plus nuclear distribution of staining. A correlation between ER and BAG-1 was also evident in breast cancer derived cell lines, as all lines examined with functional ER expression also expressed high levels of BAG-1. In addition to the prototypical 36 kDa BAG-1 isoform, breast cancer cells expressed higher molecular weight isoforms and, in contrast to BCL-2, BAG-1 expression was independent of oestrogens. BAG-1 isoforms were differentially localized to the nucleus or cytoplasm and this was also independent of oestrogens. These results demonstrate a close association between BAG-1 and functional ER expression and suggest BAG-1 may be useful as a therapeutic target or prognostic marker in breast cancer.

Mutations in SLC19A2 cause thiamine-responsive megaloblastic anaemia associated with diabetes mellitus and deafness

Thiamine-responsive megaloblastic anaemia (TRMA), also known as Rogers syndrome, is an early onset, autosomal recessive disorder defined by the occurrence of megaloblastic anaemia, diabetes mellitus and sensorineural deafness, responding in varying degrees to thiamine treatment (MIM 249270). We have previously narrowed the TRMA locus from a 16-cM to a 4-cM interval on chromosomal region 1q23.3 (refs 3,4) and this region has been further refined to a 1.4-cM interval. Previous studies have suggested that deficiency in a high-affinity thiamine transporter may cause this disorder. Here we identify the TRMA gene by positional cloning. We assembled a P1-derived artificial chromosome (PAC) contig spanning the TRMA candidate region. This clarified the order of genetic markers across the TRMA locus, provided 9 new polymorphic markers and narrowed the locus to an approximately 400-kb region. Mutations in a new gene, SLC19A2, encoding a putative transmembrane protein homologous to the reduced folate carrier proteins, were found in all affected individuals in six TRMA families, suggesting that a defective thiamine transporter protein (THTR-1) may underlie the TRMA syndrome.

Evidence for lateral gene transfer between Archaea and bacteria from genome sequence of Thermotoga maritima

The 1,860,725-base-pair genome of Thermotoga maritima MSB8 contains 1,877 predicted coding regions, 1,014 (54%) of which have functional assignments and 863 (46%) of which are of unknown function. Genome analysis reveals numerous pathways involved in degradation of sugars and plant polysaccharides, and 108 genes that have orthologues only in the genomes of other thermophilic Eubacteria and Archaea. Of the Eubacteria sequenced to date, T. maritima has the highest percentage (24%) of genes that are most similar to archaeal genes. Eighty-one archaeal-like genes are clustered in 15 regions of the T. maritima genome that range in size from 4 to 20 kilobases. Conservation of gene order between T. maritima and Archaea in many of the clustered regions suggests that lateral gene transfer may have occurred between thermophilic Eubacteria and Archaea.

Managing workers' compensation exposures in healthcare

Employees in healthcare are exposed to numerous and varied risks that pose the threat of injury. Management of those exposures by the organization will ultimately help create a safe environment for staff, patients and the public. Incorporating workers' compensation into the risk management program is the first step toward managing and reducing these exposures. This article presents a suggested outline for a written risk management plan for workers' compensation exposures.

Treatment of malnutrition with 1.1% amino acid peritoneal dialysis solution: results of a multicenter outpatient study

A peritoneal dialysis (PD) solution containing 1.1% amino acids as the osmotic agent was evaluated in a 3-month randomized, prospective, open-label study in malnourished PD patients. Patients in the treatment group (DAA) received one or two exchanges daily with the amino acid solution, depending on tolerance, in place of glucose solutions. Controls (DD) received their usual therapy with glucose dialysate. Fifty-four DAA and 51 DD patients completed the study. In DAA, but not in DD patients, there was a significant increase at month 3 in serum insulin-like growth factor-1 (IGF-1) levels and significant decreases in serum potassium (all 3 months) and inorganic phosphorus levels (months 1 and 3), indicating a general anabolic response. Prealbumin and transferrin levels were significantly increased in DAA but not in DD patients at month 1, but the groups did not differ at months 2 and 3. In patients with baseline albumin levels less than 3.5 g/dL (bromcresol green [BCG] method), DAA patients showed increases in albumin, transferrin (months 1 and 2), and prealbumin levels (all 3 months) relative to baseline values, whereas these serum protein levels were unchanged in DD patients, although the changes from baseline did not differ between groups. In this subgroup, midarm muscle circumference (MAMC) did not change in DD or DAA patients. In patients with baseline albumin levels of 3.5 g/dL or greater, DD patients had decreases in albumin and total protein levels at all 3 months and in prealbumin levels at months 1 and 2, relative to baseline. In DAA patients, there were fewer changes in serum proteins. MAMC increased significantly from baseline in DAA but not in DD patients, although changes from baseline did not differ between DAA and DD groups. DAA patients showed no changes in peritoneal membrane transport characteristics. The results indicate that treatment with one or two exchanges daily of this amino acid-based PD solution is safe and provides nutritional benefit for malnourished PD patients.

Complete genome sequence of Treponema pallidum, the syphilis spirochete

The complete genome sequence of Treponema pallidum was determined and shown to be 1,138,006 base pairs containing 1041 predicted coding sequences (open reading frames). Systems for DNA replication, transcription, translation, and repair are intact, but catabolic and biosynthetic activities are minimized. The number of identifiable transporters is small, and no phosphoenolpyruvate:phosphotransferase carbohydrate transporters were found. Potential virulence factors include a family of 12 potential membrane proteins and several putative hemolysins. Comparison of the T. pallidum genome sequence with that of another pathogenic spirochete, Borrelia burgdorferi, the agent of Lyme disease, identified unique and common genes and substantiates the considerable diversity observed among pathogenic spirochetes.

Florence Nightingale. Passionate statistician

Nightingale's passionate commitment to statistics was based on her faith in a god of order, who created a world that ran by law. God's laws could be known through research, as a result of which suitable interventions to better the world could be applied. Statistics were a vital component in her holistic approach to health care as a system. They served both to indicate serious problems and to assist in policy making, and then again to monitor the effects of the new policies. She pioneered the use of evaluative statistics and saw reforms achieved as a result of her advocacy. This article explores three key aspects selected from Nightingale's more than 40 years of applied statistical work: her adaptation of Quetelet's methodological foundations, the use of statistics in monitoring public health care systems, and her pioneering study of maternal mortality in childbirth.

Genomic sequence of a Lyme disease spirochaete, Borrelia burgdorferi

The genome of the bacterium Borrelia burgdorferi B31, the aetiologic agent of Lyme disease, contains a linear chromosome of 910,725 base pairs and at least 17 linear and circular plasmids with a combined size of more than 533,000 base pairs. The chromosome contains 853 genes encoding a basic set of proteins for DNA replication, transcription, translation, solute transport and energy metabolism, but, like Mycoplasma genitalium, it contains no genes for cellular biosynthetic reactions. Because B. burgdorferi and M. genitalium are distantly related eubacteria, we suggest that their limited metabolic capacities reflect convergent evolution by gene loss from more metabolically competent progenitors. Of 430 genes on 11 plasmids, most have no known biological function; 39% of plasmid genes are paralogues that form 47 gene families. The biological significance of the multiple plasmid-encoded genes is not clear, although they may be involved in antigenic variation or immune evasion.

The complete genome sequence of the hyperthermophilic, sulphate-reducing archaeon Archaeoglobus fulgidus

Archaeoglobus fulgidus is the first sulphur-metabolizing organism to have its genome sequence determined. Its genome of 2,178,400 base pairs contains 2,436 open reading frames (ORFs). The information processing systems and the biosynthetic pathways for essential components (nucleotides, amino acids and cofactors) have extensive correlation with their counterparts in the archaeon Methanococcus jannaschii. The genomes of these two Archaea indicate dramatic differences in the way these organisms sense their environment, perform regulatory and transport functions, and gain energy. In contrast to M. jannaschii, A. fulgidus has fewer restriction-modification systems, and none of its genes appears to contain inteins. A quarter (651 ORFs) of the A. fulgidus genome encodes functionally uncharacterized yet conserved proteins, two-thirds of which are shared with M. jannaschii (428 ORFs). Another quarter of the genome encodes new proteins indicating substantial archaeal gene diversity.

Test-retest reliability of information about employment provided in surveys by people with spinal cord injuries

Agreement was examined between the answers to an employment survey administered to discharged patients with spinal cord injury on two occasions 6 mo. apart. Analysis suggested reasonable test-retest reliability, with kappas ranging from .65 to .87 for the categorical data, e.g., current employment information and amount of time before respondents achieved any return to work.

Periodic complexes, absence-like status and suppression-burst pattern in coma following cardiorespiratory arrest

A 75-year-old man suffered a cardiac arrest and severe anoxic encephalopathy. A serial study of electroencephalograms during 4 days showed sequential changes from periodic approximately 2 Hz spike activity to absence-like status (ALS) and then into a suppression-burst pattern. Intravenous administration of phenytoin had no effect on ALS. A small dose of intravenous diazepam reduced a suppression-burst pattern. We speculate that the ALS originates in the midline structures, spreading bilaterally and synchronously to the "dysfunctional" cortex; the sustained discharges were a manifestation of associated reticular lesions, and we believe that intravenous diazepam suppressed the spread of ALS to the "dysfunctional cortex," leading to the appearance of the suppression-burst pattern. The only limitation for definitive conclusions may be a lack of postmortem verification. Autopsy findings, however, could not have confirmed the dynamic changes that occurred during the 5 days before the patients death.

Changing care staff approaches to the prevention and management of aggressive behaviour in a residential treatment unit for persons with mental retardation and challenging behaviour

The impact of a new training procedure aimed at improving staff skills in the preventative and reactive management of severely challenging behaviours was investigated within a six-place residential treatment unit. The results showed that there was some evidence to support the notion that the training reduced the number of behavioural incidents for most residents. The rates of major reactive strategy use (restraint and emergency medication) also declined over time, as did rates of staff and resident injury. Although only a limited number of these changes showed statistically significant correlations with time, it is argued that they were clinically significant when viewed against the complexity of the client group under study.

A cytosolic granzyme B inhibitor related to the viral apoptotic regulator cytokine response modifier A is present in cytotoxic lymphocytes

Using a polymerase chain reaction strategy we identified a serine proteinase inhibitor (serpin) in human bone marrow that is related to the cellular serpin proteinase inhibitor 6 (PI-6) and the viral serpin cytokine response modifier A (CrmA). This serpin, proteinase inhibitor 9 (PI-9), has an unusual reactive center P1(Glu)-P1'(Cys), which suggests that it inhibits serine proteinases that cleave after acidic residues. The only known serine proteinase with this specificity is granzyme B, a granule cytotoxin produced by cytotoxic lymphocytes. To test the interaction of PI-9 with granzyme B we prepared recombinant hexa-histidine tagged PI-9 in a yeast expression system. Addition of the recombinant protein to native granzyme B resulted in an SDS-resistant complex typical of serpin-serine proteinase interactions. Further analysis showed that complex formation followed bimolecular kinetics with a second order rate constant of 1.7 +/- 0.3 x 10(6) M-1 s-1, which is in the range for a physiologically significant serpin-proteinase interaction. Recombinant PI-9 also completely abrogated granzyme B and perforin-mediated cytotoxicity in vitro. Examination of PI-9 mRNA distribution demonstrated that it is expressed in immune tissue, primarily in lymphocytes. The highest levels of PI-9 mRNA and protein were observed in natural killer cell leukemia cell lines and in interleukin-2 stimulated peripheral blood mononuclear cells, which also produce granzyme B. Like PI-6, PI-9 was shown to be a cytosolic protein that is not secreted. Fractionation of natural killer cells and stimulated peripheral blood mononuclear cells demonstrated that PI-9 is in a separate subcellular compartment to granzyme B. These results suggest that PI-9 serves to inactivate misdirected granzyme B following cytotoxic cell degranulation. This may explain why cytotoxic cells are not damaged by their own granzyme B during destruction of abnormal cells.

Older and more moral?--age-related changes in performance on Piagetian moral reasoning tasks

Three age groups (teenage; 50-65 and 65+) completed a written version of Piaget's moral reasoning tasks to determine the general level of moral reasoning and performance on eight separate categories. Significant age effects were found. Though the nature of the age group difference was mixed, younger subjects consistently achieved lower levels of performance. Results indicate that Piaget overestimated all subjects' level of performance on his tasks and that, although there are differences in different areas of moral reasoning, the relationship with age is not uniform in its direction.