Superior venocaval obstruction secondary to central venous catheter-related thromboses in two patients with metastatic colorectal carcinoma receiving weekly 5-flurouracil. Should adjusted-dose warfarin be used as thromboprophylaxis?

Standard treatment for patients with metastatic colorectal carcinoma (MCC) involves treatment with weekly 5-flurouracil (5-FU) chemotherapy by continuous infusion, requiring the insertion of a central venous catheter (CVC). One of the main complications of CVCs is venous thromboembolic disease (VTE), with an incidence varying between 3 and 54% in different studies. During the past 14 months, 17 patients with MCC have been treated weekly with 5-FU in our unit, comprising 11 males and six females with a mean age of 60 years (range, 49-72 years). Thromboprophylaxis for all patients included 1 mg/day warfarin unless contraindicated. Three patients developed venography-confirmed CVC-related VTE, including two cases of occlusive superior venocaval VTE. All three patients were treated with intravenous thrombolytic drugs; two responded completely and one partially. We wonder whether the incidence of CVC-related VTE may be reduced further by using adjusted-dose warfarin rather than fixed low-dose warfarin. However, one has to be guarded because of the greater risk of bleeding with more intensive anticoagulation, especially in patients with liver metastases. Ongoing studies such as the warfarin prophylaxis study are essential to determine the safety and efficacy of different approaches in order to determine the optimum thromboprophylaxis for this group of patients.

Birth cohort effects in New South Wales suicide, 1865-1998

OBJECTIVE

To examine birth cohort effects in New South Wales (NSW) suicide data (1865-1998).

METHOD

Aggregate suicide data were examined after controlling for age and period using descriptive statistics and Poisson regression modelling. Three approaches were applied to address the non-identification of age, period and cohort in age-period-cohort (APC) models of suicide.

RESULTS

Apparent cohort effects in male and female suicide using a minimum constraints APC model of age, period and cohort were no longer present in female suicide when a surrogate period APC model was used, and were absent in both male and female suicide when identifiable cohort effects were isolated using a 'drift' adjusted approach to APC modelling.

CONCLUSION

Increases in youth suicide rates in NSW occurring since the 1960s cannot be attributed to cohort effects, such as family influences on development. The causes of youth suicide are thus effects operating contemporaneously.

Suicide and political regime in New South Wales and Australia during the 20th century

STUDY OBJECTIVE

Australia has had a two party parliamentary political system for most of the period since its Federation in 1901, dominated either by a social democratic (Labor) or a conservative ideological perspective. This paper investigates whether such political differences at Federal and State levels have influenced suicide rates in the state of New South Wales (NSW) for the period 1901-1998.

DESIGN

Federal government type, NSW State government type, and combinations of both Federal and NSW State government type were examined. Poisson regression models were stratified by sex and controlled for the effects of age, annual change in gross domestic product, sedative availability, drought, and both world wars.

RESULTS

When both Federal and NSW State governments were conservative the relative risk of suicide for NSW men was 1.17 (p<0.001) and for women 1.40 (p<0.001) compared with both governments being Labor (1.00). A statistically significant linear trend (p<0.001) in suicide risk was evident across the continuum of Federal/State government combinations, from both Labor (lowest), to mixed (intermediate), to both conservative (highest).

CONCLUSION

Significantly higher suicide risk was associated with conservative government tenures compared with social democratic incumbents. Results are discussed in terms of the differences underpinning conservative and social democratic government programme ideology, and their relevance to Durkheim's theories of suicide, social regulation, and integration.

The use of melatonin as an alternative to sedation in uncooperative children undergoing an MRI examination

AIM

Children who are uncooperative, due either to their age or medical condition, usually require sedation or a general anaesthetic (GA) to ensure immobility during magnetic resonance imaging (MRI) examination. These procedures have a risk of respiratory compromise and loss of vital reflexes. Melatonin induces a natural sleep with no known complication or risk of respiratory compromise. We aimed to evaluate the use of melatonin in these uncooperative children.

MATERIAL AND METHODS

An unselected group of 40 children, who had been referred for an MRI examination of the brain under sedation or GA, were chosen to receive melatonin instead. They all received 10 mg of melatonin and 17 children additionally underwent some form of sleep deprivation. The number of children who went to sleep and had a successful MRI examination was recorded.

RESULTS

Twenty-six children (65%) went to sleep and of these 22 (55%) had a successful MRI examination. In the 17 children who underwent sleep deprivation, 13 (76%) went to sleep and had a successful MRI examination. There was no complication.

CONCLUSIONS

Melatonin may provide an alternative to conventional sedation regimes and GA for uncooperative children undergoing an MRI examination. The use of sleep deprivation improves the success rate and there is no risk of respiratory compromise.

The ink4a/arf tumor suppressors cooperate with p21cip1/waf in the processes of mouse epidermal differentiation, senescence, and carcinogenesis

In mammalian cells, cell cycle withdrawal is a prerequisite for terminal differentiation. Accordingly, in most tissues, including epidermis, the expression of the cyclin-dependent kinase inhibitors increases during differentiation. However, the actual role of cyclin-dependent kinase inhibitors is unclear. Different aspects of epidermal growth and differentiation in ink4a(Delta2,3)-null, p21-null, and ink4a(Delta2,3)/p21-doubly deficient mice were studied. Altered differentiation and decreased age-related senescence were found in the epidermis of ink4a(Delta2,3)/p21-null mice and, to a lesser extent, in ink4a(Delta2,3)- and p21-null mice. ink4a(Delta2,3)/p21-null primary keratinocytes underwent cell cycle arrest upon calcium or transforming growth factor-beta treatment, but failed to differentiate. This differentiation deficiency was not observed in p21- or ink4a(Delta2,3)-deficient keratinocytes. Upon infection with a v-Ha-ras-coding retrovirus, wild-type keratinocytes displayed features indicative of premature cell senescence. In p21- or ink4a(Delta2,3)-deficient keratinocytes, only a partial response was observed. ink4a(Delta2,3)/p21-deficient keratinocytes did not display senescent features, but showed increased tumorigenic potential upon injection into nude mice. These results indicate that ink4a/arf and cip1/waf genes cooperate to allow normal keratinocyte differentiation and that the absence of both favors malignant transformation.

Routine breast screening for women aged 65-69: results from evaluation of the demonstration sites

Routine programme data and specially designed surveys from 3 demonstration sites were analysed to determine the implications of extending the NHS Breast Screening Programme (NHSBSP), to include routine invitations for women up to 69 years. All women aged 65-69 and registered with GPs in these areas received routine invitations for breast screening along with those aged 50-64. Overall uptake was 71% in women aged 65-69 compared with 78% in younger women, but was > or = 90% in both groups who had previously attended within 5 years. Recall rates were lower for older women, but with a higher positive predictive value for cancer. The percentages of invasive cancer in different prognostic categories were similar in the 2 age groups. Older women took no longer to screen than younger women. The costs per woman invited or per woman screened were also similar to those for women aged 50-64, whilst the cost per cancer detected was some 34% lower in older women. Breast screening is as cost effective for women aged 65-69 as for those aged 50-64, with a higher cancer detection rate balancing shorter life expectancy. The proposed extension to the national programme will have considerable workforce implications for the NHSBSP and require additional resources.

Altered skin development and impaired proliferative and inflammatory responses in transgenic mice overexpressing the glucocorticoid receptor

Glucocorticoids (GCs) are potent inhibitors of epidermal proliferation and effective anti-inflammatory compounds, which make them the drug of choice for a wide range of inflammatory and hyperproliferative skin disorders. GC action is mediated via the glucocorticoid receptor (GR). To study the role of GR in skin development and the molecular mechanisms underlying its action, we generated transgenic mice overexpressing GR in epidermis and other stratified epithelia, under the control of the keratin K5 promoter. Newborn mice show altered skin development, manifested as variable-sized skin lesions that range from epidermal hypoplasia and underdeveloped dysplastic hair follicles to a complete absence of this tissue. In the most affected individuals, skin was absent at the cranial and umbilical regions, and the vibrissae and eyebrows appear scarce, short, and curly. In addition, as a consequence of transgene expression in other ectodermally derived epithelia, K5-GR mice exhibited further abnormalities that strikingly resemble the clinical findings in patients with ectodermal dysplasia, which includes aplasia cutis congenita. In adult transgenic skin, topical application of the tumor promoter TPA did not elicit hyperplasia or transcriptional induction of several proinflammatory cytokines. This anti-inflammatory role of GR was due at least in part to interference with NF-kB, leading to a strong reduction in the kB-binding activity without altering the transcriptional levels of the inhibitor IkBa.

A cutaneous gene therapy approach to human leptin deficiencies: correction of the murine ob/ob phenotype using leptin-targeted keratinocyte grafts

Leptin deficiency produces a phenotype of obesity, diabetes, and infertility in the ob/ob mouse. In humans, leptin deficiency occurs in some cases of congenital obesity and in lipodystrophic disorders characterized by reduced adipose tissue and insulin resistance. Cutaneous gene therapy is considered an attractive potential method to correct circulating protein deficiencies, since gene-transferred human keratinocytes can produce and secrete gene products with systemic action. However, no studies showing correction of a systemic defect have been reported. We report the successful correction of leptin deficiency using cutaneous gene therapy in the ob/ob mouse model. As a feasibility approach, skin explants from transgenic mice overexpressing leptin were grafted on immunodeficient ob/ob mice. One month later, recipient mice reached body weight values of lean animals. Other biochemical and clinical parameters were also normalized. In a second human gene therapy approach, a retroviral vector encoding both leptin and EGFP cDNAs was used to transduce HK and, epithelial grafts enriched in high leptin-producing HK were transplanted to immunosuppressed ob/ob mice. HK-derived leptin induced body weight reduction after a drop in blood glucose and food intake. Leptin replacement through genetically engineered HK grafts provides a valuable therapeutic alternative for permanent treatment of human leptin deficiency conditions.

Regions of microsynteny in Magnaporthe grisea and Neurospora crassa

A bacterial artificial chromosome (BAC) clone containing 110,467 bp of genomic DNA from Magnaporthe grisea was sequenced, annotated, and compared to the genomes of Neurospora crassa, Candida albicans, and Saccharomyces cerevisiae. Twenty-six open reading frames (ORFs), involved in multiple biochemical pathways, were identified in the BAC sequence. A region of 53 kb, containing 18 of the 26 ORFs, was found to be syntenic to a portion of the N. crassa genome. Subregions of complete colinearity as well as interrupted colinearity were present. No synteny was evident with either C. albicans or S. cerevisiae. The identification of syntenic regions containing highly conserved genes across two genera that have been evolutionarily separated for approximately 200 million years elicits many biological questions as to the function and identity of these genes.

Sequence and chromosomal context effects on variegated expression of keratin 5/lacZ constructs in stratified epithelia of transgenic mice

The expression of transgene loci in mammals often occurs in a heterocellular fashion resulting in variegated patterns of expression. We have examined the effect of chromosomal integration site, copy number, and transcriptionally activating sequences on the variegation of a keratin 5-lacZ (K5Z) construct in the stratified epithelia of transgenic mice. lacZ expression in these mice is always mosaic, and the beta-gal activity per cell is usually higher in the lines with a higher proportion of expressing cells. Similar constructs, in which cDNAs were exchanged by lacZ sequences, showed no variegation. Also, when a strongly active, nonvariegating construct was coinjected with K5Z, most transgenic lines showed an almost homogeneous lacZ expression. The comparison of transgene arrays of different copies inserted at the same locus (obtained by using a lox/Cre system) showed that the reduction of copy number does not lead to an increase in the proportion of cells that express the transgene. Finally, in most of the variegating or nonexpressing lines the transgenes were located both at intermediate positions and at peritelomeric regions in the long chromosome arms. These findings suggest that the probability and efficiency of expression of K5Z genes depend on both long range chromosomal influences and on sequences in the transgene array.

Pathogenic infection and the oxidative defences in plant apoplast

The structural and functional continuum of the plant apoplast is the first site of contact with a pathogen and plays a crucial role in initiation and coordination of many defence responses. In this paper, we present an overview of the involvement of the plant apoplast in plant-pathogen interactions. The process of infection of French bean (Phaseolus vulgaris L.) plants by Colletotrichum lindemuthianum is analysed. The ultrastructural features of plant defence responses to fungal infection are then compared with those observed in plants or cell suspensions treated with various elicitors. Changes in cell walls and in whole plant cells responding to infection seem to be highly similar in all systems used. Model systems of French bean and white lupin (Lupinus albus L.) are then utilised to provide some biochemical characteristics of oxidative reactions in the apoplast evoked by elicitor treatment. The species specificity of various mechanisms generating reactive oxygen species is discussed, and some details of pH-dependent H2O2-generating activity of peroxidases are demonstrated. As its exocellular nature is an important feature of the oxidative burst, the major consequence of this event, i.e., the oxidative cross-linking of wall components during the papilla formation and strengthening of the walls, is analysed. Finally, the possible involvement of other wall-associated and developmentally regulated H2O2-generating mechanisms, like amine and oxalate oxidases, in plant defence is demonstrated. It is concluded that under stress conditions, such apoplastic mechanisms might be employed to increase plants' chances of survival.

Technique to measure lumbar curvature in the ergonomic evaluation of chairs: description and validation

OBJECTIVE

To describe and validate a system to record the lumbar curvature, specially designed for the ergonomic evaluation of chairs.

DESIGN

The technique consists of a flexible goniometer and requires a model of lumbar flexion (relationship between length and angle).

BACKGROUND

Most of the techniques do not allow using the backrest of the chair or do not record continuously.

METHODS

Precision, repeatability and reproducibility of the measurements have been analysed, as well as the lumbar flexion model.

RESULTS

A suitable lumbar model of flexion and the repeatability and reproducibility errors obtained are presented.

CONCLUSIONS

The linear model is a good one to represent the flexion of the lumbar spine. The measurements are reproducible and the errors are similar or lower than with conventional inclinometers. Relevance The device may help to investigate the relationship between lumbar pain and curvature, and to evaluate the lumbar curvature in sedentary work.

Physical activity patterns in normal, overweight and obese individuals using minute-by-minute accelerometry

OBJECTIVE

To determine the levels and patterns of daily physical activity in groups of normal-weight, overweight and obese adults using uniaxial minute-by-minute accelerometry.

DESIGN

Cross-sectional study of physical activity levels over a 7 day period using accelerometers programmed to collect minute-by-minute data.

SETTING

Participants were recruited from large companies in Bristol and Cardiff. All meetings took place on company premises.

PARTICIPANTS

One-hundred and eight participants volunteered for the study. Eighty-four (36 males, 48 females; 38.6+/-9.3 y) (mean+/-s.d. ) met the inclusion criteria for accelerometer measurements and were included in analyses.

RESULTS

No significant differences in physical activity were identified between normal-weight (BMI<25) and overweight (BMI 25-29.9) participants. Obese participants (BMI>30) were significantly less active than non-obese participants (BMI< or =30) during weekdays (279.1+/-77.5 vs. 391.3+/-139.4 counts min(-1); P<0.001), weekends (222.3+/-93.9 vs. 386.2+/-177.5 counts min(-1); P<0.001) and evenings (221.1+/-126.3 vs. 380.8+/-220.7 counts min(-1); P=0.002), but not at work (307.5+/-87.2 vs 398.7+/-163.3 counts min(-1); P=0.06). Differences in activity levels between obese and non-obese participants were greater in males than females. Hour-by-hour physical activity patterns demonstrated that obese participants were less active than the non-obese for almost every hour of the weekdays and the weekend.

CONCLUSIONS

Although no differences in activity emerged between overweight and normal-weight individuals, obese participants were substantially less active than the non-obese, particularly when there was a free choice of activity or no activity. The difference in activity levels was particularly pronounced in males, and unless obese individuals are compensating by lower energy intake, these activity patterns will contribute to the maintenance of or increase in the degree of obesity. Minute-by-minute accelerometry is a valuable tool for the assessment of activity patterns and may be useful to highlight periods of inactivity for intervention design.

Lasting effects of transient postinoculation tenofovir [9-R-(2-Phosphonomethoxypropyl)adenine] treatment on SHIV(KU2) infection of rhesus macaques

SHIV(KU2) replicates to high levels in inoculated macaques and reproducibly causes an acute depletion of CD4(+) T cells. We evaluated the ability of treatment with the antiretroviral drug 9-R-(2-phosphonomethoxypropyl)adenine (PMPA; tenofovir), begun 7 days postinoculation, to inhibit viral replication and associated pathogenesis. Highly productive infection (plasma viral RNA > 10(6) copy eq/mL) was present and CD4 depletion had started when treatment was initiated. PMPA treatment was associated with a rapid decline in plasma viral RNA to undetectable levels, with parallel decreases in the infectivity of plasma and infectious cells in PBMCs and CSF and stabilization of CD4(+)T-cell levels. Viral dynamics parameters were calculated for the initial phase of exponential viral replication and the treatment-related decline in plasma viremia. Following cessation of treatment after 12 weeks, plasma viral RNA was detectable intermittently at low levels, and spliced viral transcripts were detected in lymph nodes. Although treatment was begun after viral dissemination, high viremia, and CD4 decreases had occurred, following withdrawal of PMPA, CD4(+) T-cell counts normalized and stabilized in the normal range, despite persistent low-level infection. No PMPA-resistance mutations were detected. These results validate the similar viral replicative dynamics of SHIV(KU2) and HIV and SIV, and also underscore the potential for long-term modulation of viral replication patterns and clinical course by perturbation of primary infection.

Improving pediatric asthma outcomes using self-management skills

To improve pediatric asthma care in practices with limited time and staff, patients and families should be taught self-management skills to avoid crisis asthma care. A trained asthma team in a private practice setting can educate families of children with asthma. Specialized forms help the team assess a family's initial asthma knowledge, track their learning progress, and guide the staff and family during their self-management skill-development discussions. Team members ensure that the family leaves each visit with the appropriate information and skills, leading the family toward a more stable and predictable lifestyle.

Differentiation of the epithelial apical junctional complex during mouse preimplantation development: a role for rab13 in the early maturation of the tight junction

We have investigated the mechanisms by which the epithelial apicolateral junctional complex (AJC) is generated during trophectoderm differentiation in the mouse blastocyst using molecular, structural and functional analyses. The mature AJC comprises an apical tight junction (TJ), responsible for intercellular sealing and blastocoel formation, and subjacent zonula adherens E-cadherin/catenin adhesion complex which also extends along lateral membrane contact sites. Dual labelling confocal microscopy revealed that the AJC derived from a single 'intermediate' complex formed following embryo compaction at the 8-cell stage in which the TJ-associated peripheral membrane protein, ZO-1alpha- isoform, was co-localized with both alpha- and beta-catenin. However, following assembly of the TJ transmembrane protein, occludin, from the early 32-cell stage when blastocoel formation begins, ZO-1alpha- and other TJ proteins (ZO-1alpha+ isoform, occludin, cingulin) co-localized in an apical TJ which was separate from a subjacent E-cadherin/catenin zonula adherens complex. Thin-section electron microscopy confirmed that a single zonula adherens-like junctional complex present at the AJC site following compaction matured into a dual TJ and zonula adherens complex at the blastocyst stage. Embryo incubation in the tracer FITC-dextran 4 kDa showed that a functional TJ seal was established coincident with blastocoel formation. We also found that rab13, a small GTPase previously localized to the TJ, is expressed at all stages of preimplantation development and relocates from the cytoplasm to the site of AJC biogenesis from compaction onwards with rab13 and ZO-1alpha- co-localizing precisely. Our data indicate that the segregation of the two elements of the AJC occurs late in trophectoderm differentiation and likely has functional importance in blastocyst formation. Moreover, we propose a role for rab13 in the specification of the AJC site and the formation and segregation of the TJ.

System to measure the use of the backrest in sitting-posture office tasks

This paper presents an inexpensive and simple system to measure the way of use of the backrest. The system can be also used in field studies. It is based on a set of electrodes which, attached to the subject's back and the backrest, allows the contact area to be measured. A laboratory test was performed to validate the system. In the test the spontaneous use of the backrest in standard office chairs and tasks was studied. Four different types of backrest use have been detected, and it has been shown that they determine the lumbar curvature and pelvic inclination angles, as well as postural mobility. The comfort levels observed in the four types of backrest use were also different. Consequently, the system can be used as an indicator of back posture and comfort.

Endoscopic plantar fasciotomy for chronic heel pain

The purpose of our study was to determine whether endoscopic plantar fasciotomy is a safe and effective operation in this patient population. We reviewed our surgical results following endoscopic plantar fasciotomy in sixteen patients (twenty feet) with an average preoperative duration of symptoms of four years. Of the 20 feet, 9 had complete relief of pain while symptoms were improved in nine feet. One patient with bilateral symptoms had no relief in either foot. The average AOFAS hindfoot score improved from 62 to 80, a statistically significant difference. Unilateral patients did better than bilateral with no bilateral patients reporting complete resolution of symptoms. There were no iatrogenic nerve injuries. On the basis of our review, we recommend endoscopic plantar fasciotomy as an alternative to open plantar fascial release for those patients with recalcitrant heel pain.

Role of phosphorylated p50-NF-kappaB in the ultraviolet response of mouse skin

The skin constitutes a primary target for stimuli such as ultraviolet (UV) radiation and tumor promoters, leading to both inflammatory and altered proliferative responses. Since the nuclear factor kappaB (NF-kappaB) family of transcription factors plays a major role in these biological processes, we sought to elucidate its expression in newborn mouse skin upon UV and 12-O-tetradecanoylphorbol-13-acetate (TPA) exposures. We have identified the nuclear NF-kappaB binding activity in mouse skin as composed of p50/p65 heterodimers and p50 homodimers by supershift assays using different NF-kappaB-containing sequences. After UV exposure, but not TPA treatment, we detected increased NF-kappaB binding activity that correlated with a decrease of IkappaBalpha protein levels, although it was not accompanied by p50 or p65 translocation. Immunostaining of newborn mouse sections confirmed that p50 was predominantly localized in the cytoplasm of epidermal basal cells before and after UV treatment. By immunoblotting, we found distinct phosphorylated forms of p50 in cytoplasmic extracts, while only a hyperphosphorylated form was detected in nuclear extracts. In vitro dephosphorylation of skin extracts dramatically reduced the affinity of p50-containing dimers for DNA. Our data suggest that the NF-kappaB response of mouse skin to UV exposure, contrary to most stimuli in other tissues, implies additional mechanisms other than translocation, such as p50 phosphorylation.

Diagnostic imaging of renal artery stenosis

Many different imaging modalities and techniques have been used in the past for the diagnosis of renal artery stenosis. The ideal accurate, non-invasive and inexpensive diagnostic test has yet to be found but there have been promising developments during the last few years. In this review we consider in detail the use of the following tests for the diagnosis of renal artery stenosis; intravenous urography, B Mode ultrasound, Doppler ultrasound, renal scintigraphy with angiotensin-converting enzyme inhibitors, intra-venous and intra-arterial catheter angiography, computed tomographic angiography and magnetic resonance angiography. At present intra-arterial catheter angiography remains the 'gold standard' test. Magnetic resonance angiography is currently of limited availability in the United Kingdom but is the most promising new development because it is a non-invasive test which can be used to obtain both anatomical and functional information.