Fungus wars: basidiomycete battles in wood decay.

Understanding the mechanisms underlying wood decay basidiomycete community dynamics is crucial for fully understanding decomposition processes, and for modelling ecosystem function and resilience to environmental change. Competition drives community development in decaying woody resources, with interactions occurring at a distance, following physical contact, and through specialised relationships such as mycoparasitism. Outcomes of combative interactions range from replacement, where one mycelium displaces another, to deadlock, where neither combatant captures territory from the other; and a spectrum of intermediate outcomes (i.e. partial or mutual replacement) lie between these extremes. Many wood decay basidiomycetes coexist within a resource, in a complex and dynamic community, and new research techniques are focussing on spatial orientation of interactions in 3 dimensions, as opposed to historical two-dimensional research. Not only do interactions drive changes in species composition and thus wood decomposition rate, they also may have industrial applications in biocontrol of pathogenic or nuisance fungi, enzyme production, and in the production of novel antifungals and antibiotics. Altogether, fungal interactions are a fascinating and important field of study.

Interdependence of Primary Metabolism and Xenobiotic Mitigation Characterizes the Proteome of Bjerkandera adusta during Wood Decomposition.

The aim of the current work was to identify key features of the fungal proteome involved in the active decay of beechwood blocks by the white rot fungus Bjerkandera adusta at 20°C and 24°C. A combination of protein and domain analyses ensured a high level of annotation, which revealed that while the variation in the proteins identified was high between replicates, there was a considerable degree of functional conservation between the two temperatures. Further analysis revealed differences in the pathways and processes employed by the fungus at the different temperatures, particularly in relation to nutrient acquisition and xenobiotic mitigation. Key features showing temperature-dependent variation in mechanisms for both lignocellulose decomposition and sugar utilization were found, alongside differences in the enzymes involved in mitigation against damage caused by toxic phenolic compounds and oxidative stress.IMPORTANCE This work was conducted using the wood decay fungus B. adusta, grown on solid wood blocks to closely mimic the natural environment, and gives greater insight into the proteome of an important environmental fungus during active decay. We show that a change in incubation temperature from 20°C to 24°C altered the protein profile. Proteomic studies in the field of white-rotting basidiomycetes have thus far been hampered by poor annotation of protein databases, with a large proportion of proteins simply with unknown function. This study was enhanced by extensive protein domain analysis, enabling a higher level of functional assignment and greater understanding of the proteome composition. This work revealed a strong interdependence of the primary process of nutrient acquisition and specialized metabolic processes for the detoxification of plant extractives and the phenolic breakdown products of lignocellulose.

Nucleolar NF-κB/RelA mediates apoptosis by causing cytoplasmic relocalization of nucleophosmin.

In a number of contexts, and particularly in response to cellular stress, stimulation of the NF-kappaB (NF-κB) pathway promotes apoptosis. One mechanism underlying this pro-apoptotic activity is nucleolar sequestration of RelA, which is reported to cause cell death by repressing NF-κB-driven transcription. Here, we identify a novel and distinct nucleolar activity of RelA that induces apoptosis. We demonstrate, using a viral nucleolar localization signal (NoLS)-RelA fusion protein, that direct targeting of RelA to the nucleolus mediates apoptosis, independent of NF-κB transcriptional activity. We demonstrate a requirement for nucleophosmin (NPM, B23.1) in this apoptotic effect, and the apoptotic effect of stress-induced nucleolar RelA. We show by multiple approaches that nucleolar translocation of RelA is causally involved in the relocalization of NPM from the nucleolus to the cytoplasm and that RelA-induced cytoplasmic NPM mediates apoptosis by facilitating the mitochondrial accumulation of BAX. These data uncover a novel stress-response pathway and mechanism by which RelA promotes apoptosis, independent of its effects on NF-κB transcriptional activity. These findings are relevant to the design of novel anticancer agents that target RelA to this compartment.

Cost savings and quality improvement--single-use suture instruments?

AIM: To determine if the instruments found in single-use suture kits are of satisfactory quality when compared with re-useable instruments and to determine the cost implications of changing to these kits. METHODS: Audit of established practice, followed by trial of new suture kits and their introduction to the department. The new practice was then audited. A cost analysis was conducted. RESULTS: The audit showed numerous problems with the traditional suture kits (instruments were breaking or no longer suitable for suturing wounds). A trial of single-use instruments demonstrated them to be high quality and provided new instruments each time. A repeat audit at one year post-introduction demonstrated no identifiable problem with the new suture kits. The subjective impression of staff was of an improvement compared to the old kits. Costs of sterilising suture instruments were determined and it was found that single use suture kits were cost effective. Assuming an average usage of 150 kits per month, at pound 4.45 each cost for sterilisation, and a total cost of pound 3.05 each for a single-use suture kit plus dressing pack per patient, this yielded a projected cost saving of pound 2520.00 per annum. The actual cost saving was pound 1981.00 that year. The shortfall was due to overestimation of average usage. CONCLUSION: Single use instruments would appear to be safe and cost effective in the emergency department setting.

The nucleolus--a gateway to viral infection?

A number of viruses and viral proteins interact with a dynamic sub-nuclear structure called the nucleolus. The nucleolus is present during interphase in mammalian cells and is the site of ribosome biogenesis, and has been implicated in controlling regulatory processes such as the cell cycle. Viruses interact with the nucleolus and its antigens; viral proteins co-localise with factors such as nucleolin, B23 and fibrillarin, and can cause their redistribution during infection. Viruses can use these components as part of their replication process, and also use the nucleolus as a site of replication itself. Many of these properties are not restricted to any particular type of virus or replication mechanism, and examples of these processes can be found in DNA, RNA and retroviruses. Evidence suggests that viruses may target the nucleolus and its components to favour viral transcription, translation and perhaps alter the cell cycle in order to promote virus replication. Autoimmunity to nucleolin and fibrillarin have been associated with a number of diseases, and by targeting the nucleolus and displacing nucleolar antigens, virus infection might play a role in the initiation of these conditions.

Localization to the nucleolus is a common feature of coronavirus nucleoproteins, and the protein may disrupt host cell division.

The subcellular localization of transmissible gastroenteritis virus (TGEV) and mouse hepatitis virus (MHV) (group I and group II coronaviruses, respectively) nucleoproteins (N proteins) were examined by confocal microscopy. The proteins were shown to localize either to the cytoplasm alone or to the cytoplasm and a structure in the nucleus. This feature was confirmed to be the nucleolus by using specific antibodies to nucleolin, a major component of the nucleolus, and by confocal microscopy to image sections through a cell expressing N protein. These findings are consistent with our previous report for infectious bronchitis virus (group III coronavirus) (J. A. Hiscox et al., J. Virol. 75:506-512, 2001), indicating that nucleolar localization of the N protein is a common feature of the coronavirus family and is possibly of functional significance. Nucleolar localization signals were identified in the domain III region of the N protein from all three coronavirus groups, and this suggested that transport of N protein to the nucleus might be an active process. In addition, our results suggest that the N protein might function to disrupt cell division. Thus, we observed that approximately 30% of cells transfected with the N protein appeared to be undergoing cell division. The most likely explanation for this is that the N protein induced a cell cycle delay or arrest, most likely in the G(2)/M phase. In a fraction of transfected cells expressing coronavirus N proteins, we observed multinucleate cells and dividing cells with nucleoli (which are only present during interphase). These findings are consistent with the possible inhibition of cytokinesis in these cells.

The coronavirus infectious bronchitis virus nucleoprotein localizes to the nucleolus.

The coronavirus nucleoprotein (N) has been reported to be involved in various aspects of virus replication. We examined by confocal microscopy the subcellular localization of the avian infectious bronchitis virus N protein both in the absence and in the context of an infected cell and found that N protein localizes both to the cytoplasmic and nucleolar compartments.

Fingertip trauma in children from doors.

Fingertip and nailbed trauma caused by doors is common in children, occurring when fingers are either shut in the door itself or are trapped in the hinge as the door is closed. An audit was carried out over five months of all fingertip and nailbed injuries due to trauma from a door. One hundred and eighty eight children, 2% of all attendances in this period, had sustained such trauma, 39% of these occurring in children under four years of age. One hundred and forty seven children (75%) had sustained relatively minor soft-tissue injury to the finger, However the remaining forty seven (25%) of the injuries sustained were more serious e.g. Avulsion of the nail from the nailbed or amputation of part of the fingertip and 29 (15%) of all the cases required a general anaesthetic for exploration, cleaning and repair. The Plastic Surgery department followed up these 29 children and 71 Accident & Emergency follow-up appointments were generated by the remaining injuries. The incidence of significant injury was higher than expected and caused considerable distress to both the children and their parents, It is suggested that home safety protocols should feature advice on how to avoid these injuries.

Non-invasive assessment of cardiac output in children.

BACKGROUND: Stroke distance, the systolic velocity integral of aortic blood flow, is a linear analogue of stroke volume; its product with heart rate is minute distance, analogous to cardiac output. OBJECTIVE: To investigate the feasibility of assessing cardiac output in children with a simple non-invasive Doppler ultrasound technique, and to determine the normal range of values. METHODS: Peak aortic blood velocity, stroke distance, and minute distance were measured through the suprasternal window in 166 children (mean age 9.6 years, range 2-14) using a portable non-imaging Doppler ultrasound instrument. RESULTS: The technique was well tolerated by all the children participating. Mean peak aortic blood velocity was 138 cm/s and was independent of age. Mean stroke distance was 31.8 cm and showed a small but significant increase with age; mean minute distance was 2490 cm and fell with age, as did heart rate. CONCLUSIONS: Suprasternal Doppler ultrasound measurement of stroke distance is a convenient, well tolerated, non-invasive technique for the assessment of cardiac output in children. The normal range of values during childhood has been established. The technique has great potential for assessing hypovolaemia in children.

School referral survey.

Many schools refer children who have sustained an injury, directly to the local Accident & Emergency (A&E) department. This prospective study monitored these referrals for one school term (08.01.96-31.03.96). During this time 200 children under the age of 14 years presented from school to the A&E department of the Royal Aberdeen Childrens Hospital (RACH). The majority presented with trivial or mild injuries and 45% of parents felt that attending A&E was inappropriate. Half the accidents happened to unsupervised children. Rural children and children of working parents were less likely to attend A&E. In Grampian Region school referrals to A&E generate a significant workload for the A&E department with resultant cost implications. It would appear that a large number of these attendances are medically unnecessary and result from a desire by the school to avoid any complaint or litigation.

Cotranslational disassembly of flock house virus in a cell-free system.

Intact, purified particles of the nodaviruses flock house virus and nodamura virus that were either transfected into cells that were resistant to infection or introduced into in vitro translation systems directed the synthesis of viral proteins. We infer that direct interaction of these nodavirus particles with cytoplasmic components mediated virion disassembly that resulted in release of the viral RNA.

A pilot study to assess the sensitivity and specificity of an intrasound device in the diagnosis of ankle fractures.

OBJECTIVE: To investigate the use of a simple intrasound device in the detection of malleolar fractures in the accident and emergency (A&E) department. METHODS: Patients aged 16 to 70 years with ankle injuries presenting within 24 hours were considered for inclusion in the study. Those patients with bony tenderness, inability to weight bear, and swelling were examined with a simple intrasound device before x-ray examination. A positive result of discomfort, pain, withdrawal response, or combinations or these was noted. RESULTS: The device had a sensitivity of 85% and a specificity of 52% in detecting malleolar fractures. CONCLUSIONS: The use of intrasound in the detection of malleolar fractures cannot be relied upon alone, but it may help to limit the number of x rays taken unnecessarily. A further study is proposed to confirm these findings.

Combination but not single-agent methotrexate chemotherapy for gestational trophoblastic tumors increases the incidence of second tumors.

PURPOSE: No increase in second tumor incidence was found in a previous analysis of women treated with chemotherapy for gestational trophoblastic tumors (GTT). More patient years at risk enabled a further analysis of the risk of second tumors to be performed in the 1,377 women treated in this until up to 1990. PATIENTS AND METHODS: Health questionnaires were returned on 93.3% of patients who successfully completed chemotherapy and were living in the United Kingdom. The remainder were flagged for death or developing further cancers by the Office of Population Census and Surveys and by the Thames Cancer Registry. Incidence density analysis was performed based on 15,279 person-years of observation available. Standardized incidence ratio (SIR) was used to estimate the relative risk (RR) of second tumors associated with the treatment. To calculate the expected number, the actual incidence rates observed by the Thames Cancer Registry during the same calendar period of observation were used. RESULTS: An overall 50% excess of risk (RR = 1.5; 95% confidence interval [CI], 1.1 to 2.1; P < .011) was observed: there were 37 second tumors, when 24.5 were expected. For specific second tumors, the risk was significantly increased for myeloid leukemia (RR = 16.6; 95% CI, 5.4 to 38.9), colon (RR = 4.6; 95% CI, 1.5 to 10.7), and breast cancer when the survival exceeded 25 years (RR = 5.8; 95% CI, 1.2 to 16.9). The risk was not significantly increased among the 554 women receiving single-agent therapy (RR = 1.3; 95% CI, 0.6 to 2.1). Leukemias only developed in patients receiving etoposide plus other cytotoxic drugs. CONCLUSION: This study suggests that there is a slight increased risk of second tumors after sequential or combination chemotherapy for GTT. This has become apparent since the introduction of etoposide and longer follow-up.

Investigation of the control of coronavirus subgenomic mRNA transcription by using T7-generated negative-sense RNA transcripts.

The subgenomic mRNAs of the coronavirus transmissible gastroenteritis virus (TGEV) are not produced in equimolar amounts. We have developed a reporter gene system to investigate the control of this differential subgenomic mRNA synthesis. Transcription of mRNAs by the TGEV polymerase was obtained from negative-sense RNA templates generated in situ from DNA containing a T7 promoter. A series of gene cassettes was produced; these cassettes comprised the reporter chloramphenicol acetyltransferase (CAT) gene downstream of transcription-associated sequences (TASs) (also referred to as intergenic sequences and promoters) believed to be involved in the synthesis of TGEV subgenomic mRNAs 6 and 7. The gene cassettes were designed so that negative-sense RNA copies of the CAT gene with sequences complementary to the TGEV TASs, or modified versions, at the 3' end would be synthesized in situ by T7 RNA polymerase. Using this system, we have demonstrated that CAT was expressed from mRNAs derived from the T7-generated negative-sense RNA transcripts only in TGEV-infected cells and only from transcripts possessing a TGEV negative-sense TAS. Analysis of the CAT mRNAs showed the presence of the TGEV leader RNA sequence at the 5' end, in keeping with observations that all coronavirus mRNAs have a 5' leader sequence corresponding to the 5' end of the genomic RNA. Our results indicated that the CAT mRNAs were transcribed from the in situ-synthesized negative-sense RNA templates without the requirement of TGEV genomic 5' or 3' sequences on the T7-generated negative-sense transcripts (3'-TAS-CAT-5'). Modification of the TGEV TASs indicated (i) that the degree of potential base pairing between the 3' end of the leader RNA and the TGEV negative-sense TAS was not the sole determinant of the amount of subgenomic mRNA transcribed and (ii) that other factors, including nucleotides flanking the TAS, are involved in the regulation of transcription of TGEV subgenomic mRNAs.

Genetic modification and selection of microorganisms for growth on Mars.

Genetic engineering has often been suggested as a mechanism for improving the survival prospects of terrestrial microoganisms when seeded on Mars. The survival characteristics that these pioneer microorganisms could be endowed with and a variety of mechanisms by which this can be achieved are discussed, together with an overview of some of the potential hurdles that must be overcome. Also, a number of biologically useful properties for these microorganisms are presented that could facilitate the initial human colonisation and ultimately the planetary engineering of Mars.

Quantification of individual subgenomic mRNA species during replication of the coronavirus transmissible gastroenteritis virus.

A biotinylated-oligonucleotide-based method was used to isolate the subgenomic mRNAs of the coronavirus transmissible gastroenteritis virus (TGEV) to investigate the amounts of the mRNAs produced at early, middle and late times in the replication cycle. TGEV mRNA 6, which encodes the N protein, was observed to be the most abundant species throughout the replication cycle. The ratios of mRNA 6 to the other mRNAs were 1:0.11 (mRNA 2), 1:0.16 (mRNAs 3 and 4) and 1:0.37 (mRNA 5) at 12 h post-infection. All the mRNA species were differentially regulated throughout the replication cycle, although the rate of accumulation of mRNAs 4, 5 and 6, but not mRNA 3, increased markedly towards the end of the replication cycle. mRNA 7 was not detected in the system used. There was no observable correlation between the amounts of each mRNA synthesised and the potential degree of base pairing between the 3' end of the leader sequence and the transcription associated sequences on the genomic RNA at any time during the replication cycle. This indicates that the extent of base pairing was not the only factor involved in the control of subgenomic mRNA synthesis.

Section 9 police statement: a guide for junior doctors.

In England and Wales the police require medical evidence in crimes committed against a person. This will take the form of either a verbal statement given to a police officer under his/her direction, or a written report compiled by the doctor. Police surgeons regularly compile these reports without any complications. However, for many junior doctors they have potential pitfalls. This article is aimed primarily at junior doctors and GPs who are asked infrequently to provide medical evidence in criminal cases.

Characterization of the transmissible gastroenteritis virus (TGEV) transcription initiation sequence. Characterization of TGEV TIS.

The ability of the TGEV transcription initiation sequence (TIS) to produce subgenomic RNAs was investigated by placing a reporter gene, chloramphenicol acetyltransferase (CAT) under the control of either the mRNA 6 or the mRNA 7 TISs. Both constructs only produced CAT in TGEV infected cells and the amount of CAT produced from the mRNA 7 TIS was less than from the mRNA 6 TIS. Mutations were made within and around the TISs and the effect on CAT production assayed. THe results showed that the TGEV TIS acted as a initiator of transcription for CAT, though the degree of base pairing between the TIS and leader RNA was not the only factor implicated in the control transcription.