Second trimester amniotic fluid endothelin concentration. A possible predictor for pre-eclampsia

The mechanism of pre-eclampsia is still an enigma. There is now some evidence that amniotic concentrations of endothelin is elevated in pregnancies associated with pre-eclampsia. The aim of this prospective observational study was to record the concentration of amniotic fluid endothelin and compare this in women who develop pre-eclampsia and women who do not develop pre-eclampsia. Amniotic fluid concentration of endothelin is elevated by the second trimester in women who later develop pre-eclampsia.

Female genital tract morbidity and sexual function following vaginal delivery or lower segment caesarean section

A total of 208 women were assessed 2 years' post-delivery to record the prevalence of subjective urinary and faecal incontinence, incontinence of flatus, dyspareunia, subjective depression and sexual satisfaction. This was correlated with mode of delivery. A sample population was selected from the Cardiff Birth Survey Database, in accordance with strict inclusion and exclusion criteria. Each woman was invited to complete and return a postal questionnaire addressing symptoms of pelvic floor dysfunction. There was a significant decrease in sexual satisfaction scores in women who underwent vaginal delivery in comparison with those who underwent elective caesarean section at 2 years follow-up. There was also a significant increase in the prevalence of urinary incontinence, incontinence of flatus, dyspareunia and subjective depression in women who underwent vaginal delivery.

Transrectal ultrasound and the diagnosis of rectovaginal endometriosis: a prospective observational study

BACKGROUND

Rectovaginal endometriosis is a severe form of pelvic endometriosis in which pharmacological treatment is relatively ineffective (Vercellini et al., Fertil Steril. 2005;84:1375-87). Laparoscopic surgical treatment is effective, but has the potential risks of bowel perforation and colostomy formation (Darai et al., Am J Obstet Gynecol. 2005;192:394-400). Transrectal ultrasound scanning can be applied as a preoperative tool to predict the presence of rectovaginal endometriosis and bowel wall involvement (Abrao et al., J Am Assoc Gynecol Laparosc. 2004;11:50-4).

METHODS

Thirty-two women underwent transrectal ultrasound followed by therapeutic laparoscopy. Likelihood ratios and post-test prevalences were calculated with Fagan's normogram. This was then extrapolated with the aid of a mathematical model to a low-risk population.

RESULTS

A positive likelihood ratio was found to be 10.89 (95% confidence ratio (CI): 1.62-73.15) and a negative likelihood ratio was found to be 0.24 (95% CI: 0.1-0.57). The pre-test prevalence of rectovaginal endometriosis was 56%. The positive post-test prevalence probability was 93%, and the negative post-test prevalence probability was 23%.

CONCLUSION

Preoperative transrectal ultrasound scanning for rectovaginal endometriosis is an extremely accurate predictive test, and strongly predicts the need for extensive laparoscopic dissection and potential bowel resection.

Is postal follow-up of childhood cancer survivors worthwhile?

BACKGROUND

Childhood cancer survival has increased over the last 30 years, but long-term effects necessitate continued monitoring of survivors. Since not all of them attend follow-up clinics, this study assesses the efficacy of obtaining information from general practitioners (GPs) through a 5-year rolling postal program.

PROCEDURE

Survivors were included who had been diagnosed with a malignancy in the West Midlands since 1957 and were not attending central long-term follow-up clinics.

RESULTS

One thousand twenty-seven patients were followed up between 1993 and 2004. Replies were received on 903 (88% response). There were 44 subsequent malignancies and 42 deaths. No medical problems were reported in 341/935 patients (36.5%); in the other 594 endocrine effects were the most common, with visual effects the biggest single problem. Brain tumor survivors had the largest proportion of problems.

CONCLUSIONS

The response rate and information quality achieved show that this method of follow-up is feasible, in cases of discharged or defaulting patients. These data will complement those derived from hospital-based follow-up studies, to give a broader understanding of the spectrum of late effects experienced by survivors and may inform the development of specific long-term follow-up protocols.

A systematic review of the effectiveness of magnetic resonance imaging (MRI) as an addition to mammography and ultrasound in screening young women at high risk of breast cancer

Breast magnetic resonance imaging (MRI) has been proposed as an additional screening test for young women at high risk of breast cancer in whom mammography alone has poor sensitivity. We conducted a systematic review to assess the effectiveness of adding MRI to mammography with or without breast ultrasound and clinical breast examination (CBE) in screening this population. We found consistent evidence in 5 studies that adding MRI provides a highly sensitive screening strategy (sensitivity range: 93-100%) compared to mammography alone (25-59%) or mammography plus ultrasound+/-CBE (49-67%). Meta-analysis of the three studies that compared MRI plus mammography versus mammography alone showed the sensitivity of MRI plus mammography as 94% (95%CI 86-98%) and the incremental sensitivity of MRI as 58% (95%CI 47-70%). Incremental sensitivity of MRI was lower when added to mammography plus ultrasound (44%, 95%CI 27-61%) or to the combination of mammography, ultrasound plus CBE (31-33%). Estimates of screening specificity with MRI were less consistent but suggested a 3-5-fold higher risk of patient recall for investigation of false positive results. No studies assessed as to whether adding MRI reduces patient mortality, interval or advanced breast cancer rates, and we did not find strong evidence that MRI leads to the detection of earlier stage disease. Conclusions about the effectiveness of MRI therefore depend on assumptions about the benefits of early detection from trials of mammographic screening in older average risk populations. The extent to which high risk younger women receive the same benefits from early detection and treatment of MRI-detected cancers has not yet been established.

Prediction and identification of herpes simplex virus 1-encoded microRNAs

MicroRNAs (miRNAs) are key regulators of gene expression in higher eukaryotes. Recently, miRNAs have been identified from viruses with double-stranded DNA genomes. To attempt to identify miRNAs encoded by herpes simplex virus 1 (HSV-1), we applied a computational method to screen the complete genome of HSV-1 for sequences that adopt an extended stem-loop structure and display a pattern of nucleotide divergence characteristic of known miRNAs. Using this method, we identified 11 HSV-1 genomic loci predicted to encode 13 miRNA precursors and 24 miRNA candidates. Eight of the HSV-1 miRNA candidates were predicted to be conserved in HSV-2. The precursor and the mature form of one HSV-1 miRNA candidate, which is encoded approximately 450 bp upstream of the transcription start site of the latency-associated transcript (LAT), were detected during infection of Vero cells by Northern blot hybridization. These RNAs, which behave as late gene products, are not predicted to be conserved in HSV-2. Additionally, small RNAs, including some that are roughly the expected size of precursor miRNAs, were detected using probes for miRNA candidates derived from sequences encoding the 8.3-kilobase LAT, from sequences complementary to U(L)15 mRNA, and from the region between ICP4 and U(S)1. However, no species the size of typical mature miRNAs were detected using these probes. Three of these latter miRNA candidates were predicted to be conserved in HSV-2. Thus, HSV-1 encodes at least one miRNA. We hypothesize that HSV-1 miRNAs regulate viral and host gene expression.

Congenital abnormalities and clinical features associated with Wilms’ tumour: A comprehensive study from a centre serving a large population

Altogether 156 children treated for Wilms' tumour (WT) between 1970 and 1998 were studied. Sixty-six children, selected only by their attendance at clinic, were carefully examined and the findings compared to those from a case note review of 90 children. Congenital abnormalities were present in 45% of the examined cohort, in 19% of the case notes review group and in 30% overall. Novel findings included the association of WT with Marshall Smith syndrome, developmental delay in 3 of 4 cases of WT (one bilateral) and 1 sibling from consanguineous Pakistani families and another sibling also had leukaemia. The possibility of rare DNA repair or cancer predisposing disorders among these 4 families requires further study. Careful examination and history taking of an unselected patient cohort revealed a higher than expected incidence of clinical abnormalities which may be overlooked if not specifically sought.

Expression of extremely low levels of thymidine kinase from an acyclovir-resistant herpes simplex virus mutant supports reactivation from latently infected mouse trigeminal ganglia

A single-cytosine-deletion in the herpes simplex virus gene encoding thymidine kinase (TK) was previously found in an acyclovir-resistant clinical isolate. A laboratory strain engineered to carry this mutation did not generate sufficient TK activity for detection by plaque autoradiography, which detected 0.25% wild-type activity. However, a drug sensitivity assay suggested that extremely low levels of TK are generated by this virus. The virus was estimated to express 0.09% of wild-type TK activity via a ribosomal frameshift 24 nucleotides upstream of the mutation. Remarkably, this appeared to be sufficient active TK to support a low level of reactivation from latently infected mouse trigeminal ganglia.

A prospective observational study of the safety and acceptability of vaginal hysterectomy performed in a 24-hour day case surgery setting

OBJECTIVE

To assess the safety and acceptability of vaginal hysterectomy with and without simultaneous oophorectomy in a 24-hour day case surgery setting for women with nonprolapse indications for surgery.

DESIGN

Prospective observational study.

SETTING

A busy teaching hospital and tertiary referral centre for Obstetrics and Gynaecology.

POPULATION

Seventy-one women from one consultant's practice underwent a vaginal hysterectomy with a planned discharge within 24 hours after the procedure. All women had a body mass index less than 40 and a suitable home environment for routine day case surgery, other than that the women were from an unselected population.

METHOD

Prospective observational study.

MAIN OUTCOME MEASURES

The duration of the operation and mean blood loss were recorded. Any intraoperative complications were noted. In addition, the proportion of women discharged home within 24 hours of the operation was recorded together with any readmissions to hospital. Returns to theatres and any postoperative complications were also recorded. Postoperative pain scores were assessed 6 and 24 hours after procedure in selected women.

RESULTS

Seventy-one vaginal hysterectomies were performed as 24-hour day case procedures. The intraoperative complication rate was 1.4%. Sixty-five women were discharged home within 24 hours (91.5%). The readmission rate within this group was 6.2%. The duration of the procedure, mean blood loss, return to theatre rate and incidence of febrile illness were comparable with rates recorded in inpatient studies.

CONCLUSIONS

Vaginal hysterectomy performed as a 24-hour day case procedure appears to be as safe as traditional inpatient management, with a high rate of early discharge and a low rate of readmission. This may have additional advantages for the woman and healthcare provider alike.

Mutation and divergence of the phospholipase C gene in Neurospora crassa

In the fungus Neurospora crassa we have used RIP to obtain a presumptive null mutation of the phospholipase C-1 gene, thought to be important in intracellular calcium signaling, notably maintenance of the tip-high calcium gradient. The mutant is viable but has slow, aberrant growth and branching. Hence plc-1 is not required for polar growth at the tip, but is necessary to modulate growth to give normal form. The mutant has residual PLC activity suggesting that this enzyme function can be provided from other parts of the genome. Sequencing natural isolates has shown that the plc-1 gene is highly variable in nature. A large proportion of the variable sites are in a region that is unique to Neurospora. A phylogeny for this gene shows that New and Old World strains have diverged the most. Within the Americas, morphs are found throughout the continent suggesting extensive strain dispersal.

Competition and complementation between thymidine kinase-negative and wild-type herpes simplex virus during co-infection of mouse trigeminal ganglia

Laboratory strains of herpes simplex virus lacking thymidine kinase (TK) cannot replicate acutely to detectable levels in mouse trigeminal ganglia and do not reactivate from latency. However, many pathogenic clinical isolates that are resistant to the antiviral drug acyclovir are heterogeneous populations of TK-negative (TK(-)) and TK-positive (TK(+)) viruses. To recapitulate this in vivo, mice were infected with mixtures of wild-type virus and a recombinant TK(-) mutant in various ratios. Following co-infection, the replication, number of latent viral genomes and reactivation efficiency of TK(+) virus in trigeminal ganglia were reduced in a manner related to the amount of TK(-) virus in the inoculum. TK(+) virus did not always complement the acute replication or increase the number of latent viral genomes of TK(-) mutant in mouse ganglia. Even so, TK(+) virus could still confer the pathogenic phenotype to a TK(-) mutant, somehow providing sufficient TK activity in trans to permit a TK(-) mutant to reactivate from latently infected ganglia.

Low-level expression and reversion both contribute to reactivation of herpes simplex virus drug-resistant mutants with mutations on homopolymeric sequences in thymidine kinase

Many acyclovir-resistant herpes simplex virus isolates from patients contain insertions or deletions in homopolymeric sequences in the thymidine kinase (TK) gene (tk). Viruses that have one (G8) or two (G9) base insertions in a run of seven G's (G string) synthesize low levels of active TK (TK-low phenotype), evidently via ribosomal frameshifting. These levels of TK can suffice to permit reactivation from latently infected mouse ganglia, but in a majority of ganglia, especially with the G9 virus, reactivation of virus that has reverted to the TK-positive phenotype predominates. To help address the relative contributions of translational mechanisms and reversion in reactivation, we generated viruses with a base either inserted or deleted just downstream of the G string. Both of these viruses had a TK-low phenotype similar to that of the G8 and G9 viruses but with less reversion. Both of these viruses reactivated from latently infected trigeminal ganglia, albeit inefficiently, and most viruses that reactivated had a uniformly TK-low phenotype. We also generated viruses that have one insertion in a run of six C's or one deletion in a run of five C's. These viruses lack measurable TK activity. However, they reactivated from latently infected ganglia, albeit inefficiently, with the reactivating viruses having reverted to the wild-type TK phenotype. Therefore, for G-string mutants, levels of active TK as low as 0.25% generated by translational mechanisms can suffice for reactivation, but reversion can also contribute. For viruses that lack TK activity due to mutations on other homopolymeric sequences, reactivation can occur via reversion.

An investigation into the kerbside recycling behaviour of two Welsh case study authorities

This paper investigates the number of observed households setting out their containers for kerbside recyclable collection in two Welsh kerbside recycling programmes; namely, Rhondda Cynon Taf County Borough Council and Caerphilly County Borough Council. Analysed data from the monitoring of approximately 114 000 households in the two separate kerbside programmes are presented, making this the largest study of kerbside recycling behaviour in the UK. The average household set-out rates of individual households per electoral division and per street in each programme were compared. Average household set-out rate for a particular electoral division and street was then related to certain socio-economic indicators. The study was performed using the 'ArcView' geographical information systems (GIS) package. The model identified a moderate link between household set-out rate (%) and socio-economic status at electoral division level. However, there was no correlation between socio-economic status and average household set-out rate in a street. Household set-out rates for both programmes fluctuated significantly in streets with similar socio-economic status. Another significant factor affecting set-out rate, herein named the 'Nant-y-Gwyddon effect', is also described.

Work design and management in the manufacturing sector: development and validation of the Work Organisation Assessment Questionnaire

OBJECTIVES

To examine the factor structure, reliability, and validity of a new context-specific questionnaire for the assessment of work and organisational factors. The Work Organisation Assessment Questionnaire (WOAQ) was developed as part of a risk assessment and risk reduction methodology for hazards inherent in the design and management of work in the manufacturing sector.

METHOD

Two studies were conducted. Data were collected from 524 white- and blue-collar employees from a range of manufacturing companies. Exploratory factor analysis was carried out on 28 items that described the most commonly reported failures of work design and management in companies in the manufacturing sector. Concurrent validity data were also collected. A reliability study was conducted with a further 156 employees.

RESULTS

Principal component analysis, with varimax rotation, revealed a strong 28-item, five factor structure. The factors were named: quality of relationships with management, reward and recognition, workload, quality of relationships with colleagues, and quality of physical environment. Analyses also revealed a more general summative factor. Results indicated that the questionnaire has good internal consistency and test-retest reliability and validity. Being associated with poor employee health and changes in health related behaviour, the WOAQ factors are possible hazards. It is argued that the strength of those associations offers some estimation of risk. Feedback from the organisations involved indicated that the WOAQ was easy to use and meaningful for them as part of their risk assessment procedures.

CONCLUSIONS

The studies reported here describe a model of the hazards to employee health and health related behaviour inherent in the design and management of work in the manufacturing sector. It offers an instrument for their assessment. The scales derived which form the WOAQ were shown to be reliable, valid, and meaningful to the user population.

Surgical treatment of fibroids for subfertility

BACKGROUND

Fibroids are benign tumours of the uterus occurring in up to 77% of women. Fibroids have been noted to occur more frequently in women with infertility. Retrospective studies have suggested the benefit of surgically removing fibroids to increase the fertility efficacy of both natural conception and assisted conception. There are a variety of methods to surgically remove fibroids including laparotomy, laparoscopy and hysteroscopy. The relative advantages and disadvantages of these modalities in terms of fertility efficacy and side effects are unknown.

OBJECTIVES

To determine the efficacy and safety of the removal of uterine fibroids in subfertile women by laparotomy, laparoscopy or hysteroscopy when compared with expectant management or each other. The review will include also new surgical approaches as and when they are trialed.

SEARCH STRATEGY

We searched the Cochrane Menstrual Disorders and Subfertility Review Group Specialised register of controlled trials, MEDLINE (PUBMED) 1985 to 2004, EMBASE (1985 to 2004), CINAHL (1985 to 2004) and National Research Register.

SELECTION CRITERIA

Randomised controlled trials (RCTs) in which fibroids were removed via surgery for the treatment of infertility

DATA COLLECTION AND ANALYSIS

Three authors independently assessed trial quality and extracted data.

MAIN RESULTS

Only one randomized controlled study was included (131 women) and this was probably underpowered. There was no evidence of a difference in outcome in terms of clinical pregnancy rate and live birth rate when fibroids were removed via laparotomy or laparoscopy for infertility. There were some non fertility benefits of removal via laparoscopy including shorter hospital stay, less febrile illness and a smaller drop in pre-operative haemoglobin concentration when compared to laparotomy. There were no randomised controlled studies comparing hysteroscopic removal or no intervention with other surgical modalities.

AUTHORS' CONCLUSIONS

There is limited evidence to suggest that there is no difference in fertility efficacy outcome if fibroids are removed via laparotomy when compared to laparoscopy. There is no good randomised controlled evidence to support hysteroscopic removal of fibroids compared to other surgical modalities for fertility efficacy.

Association between urinary tract infection and postmicturition wiping habit

Urinary tract infections are common in pregnancy. In pregnancy urinary tract infections have an associated risk of premature labour. This study looks at the incidence of urinary tract infections and the method of perineal hygiene used after urination. Wiping back to front is associated with a greater risk of developing urinary tract infection than wiping front to back.

Dealing with self-management of chronic illness at work: predictors for self-disclosure

This paper explores the role of self-management of chronic illness at work, as a predictor for self-disclosure. The study reports findings from a survey sent to all staff at a UK university, of which 610 employees reported managing a chronic illness: arthritis, musculoskeletal pain, diabetes, asthma, migraine, heart disease, irritable bowel syndrome and depression. The study found that discrete self-management factors predicted different levels of disclosure: partial self-disclosure (employees informing line managers about the presence of a chronic illness) and full self-disclosure (employees informing line managers how that chronic illness affected them at work). For partial disclosure, a greater reported experience of chronic illness by employees was positively associated with self-disclosure. For full-disclosure, employees were more likely to report disclosure to line managers if they had already disclosed to colleagues, and if they perceived receiving support from their line managers in relation to their chronic illness as important. Except for academics who were least likely to disclose, occupational groups did not emerge as significant predictors for either partial or full disclosure. Except for diabetes, chronic illness itself was not a significant predictor or barrier to self-disclosure. Our findings suggest that chronically ill employees adopt a disclosure strategy specifically related to different self-management needs of chronic illness at work.

The role and applications of ultrasound in ambulatory gynaecology

Ultrasound has changed gynaecological practice and continues to do so. One of the earliest applications of abdominal scanning in gynaecology was for monitoring follicular development during fertility treatment with clomiphene citrate or gonadotrophins in the 1960s and 1970s. Subsequently, it was natural that with the introduction of in vitro fertilization, abdominal and transvaginal ultrasound played a key role in the development of oocyte retrieval techniques. These were truly the first interventional ultrasound-guided ambulatory procedures in gynaecology. In this chapter, the reader will be introduced to the roles that the various ultrasound modalities play in our current daily practice, and how they have changed the management of numerous gynaecological conditions in both diagnostic and therapeutic contexts. We will also outline the recent developments and the 'hot' research topics in this field.

An unusual internal ribosome entry site in the herpes simplex virus thymidine kinase gene

We have investigated a herpes simplex virus mutant that expresses low levels of thymidine kinase (TK), a phenotype associated with drug resistance and pathogenicity, despite a single-base deletion in the gene. Using a dual-reporter system, a 39-nt sequence including the mutation was shown to direct expression of the downstream reporter gene in reticulocyte lysate. Translation of the downstream reporter was not impaired when the mRNA lacked a 5' cap or had a stable stem loop 5' of the upstream reporter and was relatively resistant to edeine, an antibiotic that prevents AUG codon recognition by the 40S-eIF2-GTP/Met-tRNAi complex. Twelve nucleotides were as active as the original sequence for translation of the downstream reporter. Surprisingly, this sequence lacks an AUG codon. Analysis of point mutations showed that a CUG codon in the sequence was important. However, many single-base changes had only limited effects, and introduction of AUG codons did not increase translation. A mutant virus containing both the single-base deletion and a mutation that reduced downstream translation in vitro had significantly less TK activity than a virus with the single-base deletion alone. Thus, a remarkably short internal ribosome entry site (IRES) that lacks an AUG codon resides in the viral tk gene. The IRES appears to be responsible for TK expression from a drug-resistant mutant that would otherwise express no TK, which may contribute to pathogenicity. Because we found numerous short sequences with IRES activity, there might be many hitherto unrecognized polypeptides expressed at low levels from eukaryotic mRNAs.

A microsatellite map of white clover

The white clover ( Trifolium repens) nuclear genome (n = 2x = 16) is an important yet under-characterised genetic environment. We have developed simple sequence repeat (SSR) genetic markers for the white clover genome by mining an expressed sequence tag (EST) database and by isolation from enriched genomic libraries. A total of 2,086 EST-derived SSRs (EST-SSRs) were identified among 26,480 database accessions. Evaluation of 792 EST-SSR primer pairs resulted in 566 usable EST-SSRs. Of these, 335 polymorphic EST-SSRs, used in concert with 30 genomic SSRs, detected 493 loci in the white clover genome using 92 F1 progeny from a pair cross between two highly heterozygous genotypes--364/7 and 6525/5. Map length, as estimated using the joinmap algorithm, was 1,144 cM and spanned all 16 homologues. The R (red leaf) locus was mapped to linkage group B1 and is tightly linked to the microsatellite locus prs318c. The eight homoeologous pairs of linkage groups within the white clover genome were identified using 96 homoeologous loci. Segregation distortion was detected in four areas (groups A1, D1, D2 and H2). Marker locus density varied among and within linkage groups. This is the first time EST-SSRs have been used to build a whole-genome functional map and to describe subgenome organisation in an allopolyploid species, and T. repens is the only Trifolieae species to date to be mapped exclusively with SSRs. This gene-based microsatellite map will enable the resolution of quantitative traits into Mendelian characters, the characterisation of syntenic relationships with other genomes and acceleration of white clover improvement programmes.

Adrenal suppression from high-dose inhaled fluticasone propionate in children with asthma

This cross-sectional study was designed to examine the prevalence of adrenocortical suppression in children with asthma treated with high-dose inhaled fluticasone propionate (FP). Children and adolescents (n=50) with asthma, treated with inhaled FP at a dose of > or = 1,000 mg a day for > or = 6 months, were enrolled. Early morning serum cortisol was performed. Subjects with a serum cortisol of < 400 nmol x L(-1) had a tetracosactrin stimulation test. Fifty subjects of mean age 13.1 yrs were treated with a mean dose of 924.7 microg x m(-2) x day(-1) FP for a mean duration of 2 yrs. Of the 50 subjects, 36 (72%) had serum cortisol levels of < 400 nmol x L(-1) and underwent tetracosactrin stimulation test. Of these, 6 (17%) demonstrated a less than two-fold increase in serum cortisol from baseline and peak cortisol level of < or = 550 nmol x L(-1) at 30 or 60 min poststimulation. There was a significant negative correlation between the dose of FP x m(-2) and stimulated peak cortisol level. Biochemical evidence of adrenocortical insufficiency was demonstrated in 12% of the subjects, indicating that high-dose fluticasone propionate use may be associated with dose-dependent adrenocortical suppression.

Translational compensation of a frameshift mutation affecting herpes simplex virus thymidine kinase is sufficient to permit reactivation from latency

Herpes simplex virus thymidine kinase is important for reactivation of virus from its latent state and is a target for the antiviral drug acyclovir. Most acyclovir-resistant isolates have mutations in the thymidine kinase gene; however, how these mutations confer clinically relevant resistance is unclear. Reactivation from explanted mouse ganglia was previously observed with a patient-derived drug-resistant isolate carrying a single guanine insertion within a run of guanines in the thymidine kinase gene. Despite this mutation, low levels of active enzyme were synthesized following an unusual ribosomal frameshift. Here we report that a virus, generated from a pretherapy isolate from the same patient, engineered to lack thymidine kinase activity, was competent for reactivation. This suggested that the clinical isolate contains alleles of other genes that permit reactivation in the absence of thymidine kinase. Therefore, to establish whether thymidine kinase synthesized via a ribosomal frameshift was sufficient for reactivation under conditions where reactivation requires this enzyme, we introduced the mutation into the well-characterized strain KOS. This mutant virus reactivated from latency, albeit less efficiently than KOS. Plaque autoradiography revealed three phenotypes of reactivating viruses: uniformly low thymidine kinase activity, mixed high and low activity, and uniformly high activity. We generated a recombinant thymidine kinase-null virus from a reactivating virus expressing uniformly low activity. This virus did not reactivate, confirming that mutations in other genes that would influence reactivation had not arisen. Therefore, in strains that require thymidine kinase for reactivation from latency, low levels of enzyme synthesized via a ribosomal frameshift can suffice.

High-frequency phenotypic reversion and pathogenicity of an acyclovir-resistant herpes simplex virus mutant

A double-guanine-insertion mutation within a run of guanines in the herpes simplex virus gene encoding thymidine kinase (TK) was previously found in an acyclovir-resistant clinical isolate. This mutation was engineered into strain KOS, and stocks were generated from single plaques. Plaque autoradiography revealed that most plaques in such stocks exhibited low levels of TK activity, while approximately 3% of plaques exhibited high levels of TK activity, indicating a remarkably high frequency of phenotypic reversion. This virus was able to reactivate from latency in mouse ganglia; a fraction of the reactivating virus expressed a high level of TK activity due to an additional G insertion, suggesting that the observed genetic instability contributed to pathogenicity.

Can't or won't? Evidence relating to authorship in facilitated communication

Most experimental evaluations of Facilitated Communication (FC) provide no evidence that this technique is valid. Important as they are, controlled test-based studies have characteristically not done justice to the complexity of the issues which surround FC. This paper summarises a long term evaluation project involving various forms of data collection. In this study too, controlled testing has shown very little evidence for the validity of the technique. In contrast, other sources of data, including records of naturally occurring message passing and intensive video analysis have provided evidence that the communication skills of some FC users have been enhanced. An overview of the project is presented, and discussed in relation to the blurring of findings (observations of behaviour) and inferences (judgements of communicative competence) in the extant literature.

Outcomes from paired single-lung transplants from the same donor

BACKGROUND AND METHODS

Simultaneous, paired single-lung transplants from a single organ donor is one way to maximize lung transplant opportunities. Paired transplants allow comparison between left and right single-lung transplants and also provide insight into the relevance of donor vs recipient factors in rejection outcomes.

RESULTS

Of 76 paired transplants (38 pairs) performed at the Alfred Hospital, 68 patients have survived >30 days. We observed no significant differences between left and right single-lung transplants in ICU stay (median, 3.1 vs 3.0 days; range, 0.5 to 83 vs 0.5 to 76 days), hospital stay (median, 19.5 vs 24.0 days; range, 1 to 118 vs 11 to 144 days), airway complications (5 vs 3), and 5-year survival (60% vs 50%). The 6 month, and 1- and 2-year survivals were lower in left single-lung transplant recipients, primarily related to increased mortality from airway complications. In 28 pairs, both recipients survived 90 days, and the incidence, frequency, and time of onset of acute rejection and chronic rejection (bronchiolitis obliterans syndrome [BOS]) were not significantly different. When sequentially performed lung transplants were separately analyzed, the incidence of acute rejection was not related to graft ischemic time.

CONCLUSIONS

The general outcomes of right and left transplants are similar, although we observed increased 6-month to 2-year mortality associated with left lung transplantation. The lack of correlation between the incidence of acute rejection episodes or the severity of BOS in paired allograft recipients suggests that "donor factors" are not the dominant cause.

Designing and managing healthy work for older workers

Throughout many countries in the developed world, largely because of increasing life expectancy, the population is ageing. One of the economic implications of this demographic change is that workers may need to work longer and retire later than they have done in recent years. Much needs to be done to ensure that work remains a positive experience for workers throughout their career trajectories, and that it does not damage their health. The major contemporary challenges to health at work are those associated with the way work and work organizations are designed and managed. This is especially true for older workers. This paper focuses on the relationships between age and work performance, between age and work-related health, and between age and work-related stress. It concludes that there remains considerable scope for designing optimal work systems to harness the potential and protect the health of older workers. This important initiative will require a co-ordinated and multidisciplinary occupational health strategy.

The H1 histone variant of tomato, H1-S, is targeted to the nucleus and accumulates in chromatin in response to water-deficit stress

Water deficit has a significant impact on patterns of gene expression. Based on the deduced amino acid sequence, it has been proposed that the drought and abscisic acid-induced gene (his1-s) of tomato (Lycopersicon esculentum Mill.) encodes an H1 histone variant. To study the role of H1-S it is important to understand the expression characteristics of the protein. To identify the his1-s product in vivo the his1-s cDNA was fused to a (His)6 tag and overexpressed in Escherichia coli. The H1-S fusion protein was used to generate an antibody that recognized a protein with an apparent molecular weight of 31 kDa that accumulates in response to water deficit in the whole plant and detached leaves. A time course of his1-s expression showed that protein accumulation is delayed compared to the mRNA accumulation in both the whole plant and detached leaves. Cellular fractionation, immunofluorescence and H1-S::beta-glucuronidase fusion analyses in transgenic tissues were used to determine the cellular localization of H1-S. The results showed that H1-S accumulates in nuclei and is associated with chromatin of wilted tomato leaves. The drought- and abscisic acid-induced gene his1-s encodes a linker-histone subtype specifically accumulated in the nuclei and chromatin of tomato leaves subjected to water-deficit conditions. Although the molecular mechanism of H1-S function is still unclear, the expression characteristics of H1-S are consistent with a potential role of this protein in the regulation of gene expression in response to water deficit.

Maximizing thoracic organ transplant opportunities: the importance of efficient coordination

BACKGROUND

In Australia, despite large distances and one of the world's lowest multiorgan donor rates (11.4/million population/year), the thoracic organ transplant (TOTx) rate of 9.6/million population/year is one of the world's highest.

METHODS

As an example of the Australian approach, a system of transplant coordination and organ allocation has evolved at the Alfred Hospital. Donor organs are assigned locally, or between the 4 major TOTx units on rotation. The recipient team then selects appropriate recipients, matching by blood group, size, cytomegalovirus (CMV) status, prospective cross matching and clinical status. An experienced recipient coordinator takes responsibility for organization of the retrieval and transplant process, including all operating room staff, all medical personnel, and transport for the donor team and the potential TOTx recipients.

RESULTS

Between February 1989 and February 1999, 307 hearts, 48 heart/ lung, 124 single and 116 bilateral lung transplants were performed from 452 donor offers (52% beyond 500 miles). This represents 1.74 organs transplanted/thoracic donor and compares favourably to American United Network for Organ Sharing (1.43) and European (1.3) figures.

CONCLUSIONS

The Australia TOTx model has enabled high transplant rates by efficiently using the available donor organs. This has been achieved through an enlarged, experience TOTx team, the optimizing of donor acceptance criteria and improving coordination logistics to allow multiple thoracic procedures simultaneously.