Choosing metaphases for biological dosimetry by fluorescence in situ hybridization (FISH)

Data are presented for a subset of lymphocytes characterized by FISH as missing painted chromosomal material. These lymphocytes occur in both control and irradiated subjects. These cells have a much greater frequency of one-way translocations than cells in which all of the painted chromosomal material is present. Their presence contributes to interindividual variability in control translocation yields. These cells do not appear to be more prevalent in persons exposed to high radiation doses. It is suggested that their exclusion when selecting cells for analysis may improve the sensitivity of FISH as a biological dosimeter at low doses. Mechanisms for the production of these one-way translocations in vivo are also discussed, with a proposal that their variable frequency in individuals may be consistent with exposure to chemical clastogens.

American Indians with HIV/AIDS: health and social service needs, barriers to care, and satisfaction with services among a Western tribe

This study investigated the health care and social service needs, barriers to care and satisfaction with services among American Indians with HIV/AIDS in a western tribe. Individual interviews were conducted with 28 respondents, which constituted nearly the entire population obtaining HIV/AIDS medical services from the IHS in the target area. The survey found that expressed need for services in this frontier rural area were lower than urban counterparts, but that access to needed services was lower. Common unmet medical needs include mental health services, eye and dental care, traditional Native medicine, and substance abuse treatment. Common unmet social service needs include housing assistance, help obtaining food and clothing, and transportation. Limited access to essential services impedes the ability of American Indians with HIV/AIDS to maintain effective medical regimens.

Structure of Thermotoga maritima stationary phase survival protein SurE: a novel acid phosphatase

BACKGROUND

The rpoS, nlpD, pcm, and surE genes are among many whose expression is induced during the stationary phase of bacterial growth. rpoS codes for the stationary-phase RNA polymerase sigma subunit, and nlpD codes for a lipoprotein. The pcm gene product repairs damaged proteins by converting the atypical isoaspartyl residues back to L-aspartyls. The physiological and biochemical functions of surE are unknown, but its importance in stress is supported by the duplication of the surE gene in E. coli subjected to high-temperature growth. The pcm and surE genes are highly conserved in bacteria, archaea, and plants.

RESULTS

The structure of SurE from Thermotoga maritima was determined at 2.0 A. The SurE monomer is composed of two domains; a conserved N-terminal domain, a Rossman fold, and a C-terminal oligomerization domain, a new fold. Monomers form a dimer that assembles into a tetramer. Biochemical analysis suggests that SurE is an acid phosphatase, with an optimum pH of 5.5-6.2. The active site was identified in the N-terminal domain through analysis of conserved residues. Structure-based site-directed point mutations abolished phosphatase activity. T. maritima SurE intra- and intersubunit salt bridges were identified that may explain the SurE thermostability.

CONCLUSIONS

The structure of SurE provided information about the protein's fold, oligomeric state, and active site. The protein possessed magnesium-dependent acid phosphatase activity, but the physiologically relevant substrate(s) remains to be identified. The importance of three of the assigned active site residues in catalysis was confirmed by site-directed mutagenesis.

A case of Brown-Sequard syndrome with associated Horner's syndrome after blunt injury to the cervical spine

A 26 year old motorcyclist was received by the trauma team in our accident and emergency department after a head on collision with a motor vehicle. He had been correctly immobilised and his primary survey was essentially normal. He was alert and orientated with a Glasgow Coma score of 15 and had no symptoms or signs of spinal injury. His cervical spine radiography was also normal. Neurological examination however, revealed anisocoria, his left pupil being smaller than his right, and a Brown-Sequard syndrome, with a sensory level at C6. Immobilisation was maintained and he was transferred to the regional neurosurgical centre where magnetic resonance imaging revealed a contusion of the left half of the spinal cord adjacent to the 6th cervical vertebrae. Computed tomography revealed no bony injury but spinal column instability was demonstrated after flexion-extension spinal views and he underwent surgery to fuse his spine at the C5-C6 level. This report highlights the necessity to observe strict ATLS guidelines. This must include a thorough examination of the central and peripheral nervous system where spinal injury is suspected, even in the absence of radiographic abnormality and neck pain. This article also presents the unusual phenomena of Brown-Sequard syndrome and unilateral Horner's syndrome after blunt traumatic injury to the cervical spine.

Understanding risk and lessons for clinical risk communication about treatment preferences

This paper defines risk and its component elements and describes where clinical practice may be starting from in terms of what is reported in the literature about understanding risks and the information requirements of consumers. It notes briefly how theoretical models in the literature contribute to our understanding by providing a basis from which to summarise current evidence about the effects of healthcare interventions which address risks and risk behaviour. The situations or types of interventions in which risk related interventions are most effective are described, but a significant caveat is noted about the types of outcomes which have been reported in the literature and which are most appropriate to evaluate. The effects of "framing" variations in the information given to consumers and the ethical dilemmas these raise for a debate about "informed choice" in healthcare programmes are discussed. In response to both the practical and ethical dilemmas that arise from the current evidence, some of the areas where attention should be focused in the future are outlined so that both health gain and informed choice might be achieved. These include the use of decision aids, although their implementation is not widespread at present. Lessons from the current literature on how further progress can be made towards improved communication, discussion between professionals and consumers, and enhancing informed choice are discussed.

Transport of plasma proteins across vasa recta in the renal medulla

In this study, we have extended a mathematical model of microvascular exchange in the renal medulla to elucidate the mechanisms by which plasma proteins are transported between vasa recta and the interstitium. In contrast with other work, a distinction was made between the paracellular pathway and the transcellular route (i.e., water channels) in descending vasa recta (DVR). Our model first indicates that concentration polarization on the interstitial side of vasa recta has a negligible effect on medullary function. Our results also suggest that, whereas proteins are cleared from the interstitium by convection, both diffusion and convection play a role in carrying proteins to the interstitium. In those regions where transcapillary oncotic pressure gradients favor volume influx through the paracellular pathway in DVR, diffusion is the only means by which proteins can penetrate the interstitium. Whether the source of interstitial protein is DVR or ascending vasa recta depends on medullary depth, vasa recta permeability to proteins, and vasa recta reflection coefficients to small solutes and proteins. Finally, our model predicts significant axial protein gradients in the renal medullary interstitium.

Antibiotics and shared decision-making in primary care

Antibiotics are often prescribed to patients with respiratory tract infections who are unlikely to benefit. Models of physician-patient interaction may help understanding of this problem and inform the design of communication skills interventions to enhance appropriate prescribing. The 'paternalistic model' of the consultation remains common in the setting of acute respiratory tract infections. However, the four assumptions that could support this model are not valid for most of these patients, because: best treatment is controversial; management is inconsistent; physicians are not in the best position to evaluate trade-offs between management options without understanding patients' perspectives; and many pressures (apart from patients' agendas) intrude into the consultation. One alternative is the 'informed model' of consulting, but this does not take society's interests into account. The 'shared decision-making model', however, provides a framework for addressing both clinicians' and patients' agendas, and could guide the development and evaluation of specific consultation strategies to promote more appropriate use of antibiotics in primary care.

Consumers' views of quality in the consultation and their relevance to 'shared decision-making' approaches

BACKGROUND

There is a recognized need to assess the effects of shared decision-making and other communication interventions. However, the outcomes usually assessed for evidence of 'effectiveness' are determined by researchers and have not been based on consumers' views.

AIM

This study aimed to identify the important outcomes of consultations for consumers, and to compare with those reported in the current literature.

SETTING AND PARTICIPANTS

Forty-seven participants attending six focus group interviews. Most interviews took place in and all were orientated towards the UK primary care setting.

METHODS

Focus group study.

RESULTS

Many affective outcomes were identified, consistent with the current literature trends. However, many cognitive and behavioural outcomes that are assessed in the current literature were not noted by participants as important. Furthermore, a broader range of outcomes than is evident in the current literature was viewed as important to these participants.

CONCLUSIONS

There is a need to revisit the outcomes which are assessed in decision-making and communication research. The outcomes of greatest importance to consumers must be identified and confirmed by new research which is based directly on the views of consumers themselves.

Understanding risk and lessons for clinical risk communication about treatment preferences

This paper defines risk and its component elements and describes where clinical practice may be starting from in terms of what is reported in the literature about understanding risks and the information requirements of consumers. It notes briefly how theoretical models in the literature contribute to our understanding by providing a basis from which to summarise current evidence about the effects of healthcare interventions which address risks and risk behaviour. The situations or types of interventions in which risk related interventions are most effective are described, but a significant caveat is noted about the types of outcomes which have been reported in the literature and which are most appropriate to evaluate. The effects of "framing" variations in the information given to consumers and the ethical dilemmas these raise for a debate about "informed choice" in healthcare programmes are discussed. In response to both the practical and ethical dilemmas that arise from the current evidence, some of the areas where attention should be focused in the future are outlined so that both health gain and informed choice might be achieved. These include the use of decision aids, although their implementation is not widespread at present. Lessons from the current literature on how further progress can be made towards improved communication, discussion between professionals and consumers, and enhancing informed choice are discussed.

Decision analysis in patient care

To help patients to fully participate in shared decision making is becoming an important goal in clinical practice and one which is receiving increasing attention in terms of the requisite skills and technological development. We discuss the potential application of decision analysis-a specific technology that has been introduced into clinical practice but to date only within research contexts-and examine the usefulness and feasibility of the technique for patients, particularly in settings where clinical presentations are diverse and characterised by uncertainty.

Analysis of loss of heterozygosity in lymphoma and leukaemia arising in F1 hybrid mice locates a common region of chromosome 4 loss

Previous studies have identified five lymphoma-related tumour suppressor gene regions on murine chromosome 4. Using detailed allelotype analysis on a range of lympho-haematopoietic tumour types arising in F1 hybrid mice, we now show a consistent pattern of loss of heterozygosity (LOH) which identifies a common region of loss delineated by microsatellites D4Mit21 and D4Mit53 on proximal chromosome 4. This critical segment corresponds to the thymic lymphoma tumour suppressor region 5 (TLSR5) identified in an earlier study. Tumours of this type have also been reported as showing allelic loss from the Trp53 and Ikaros regions on chromosome 11. In the present study, only a small fraction of tumours showed LOH in the Ikaros region, while a minority of lymphomas, but not acute myeloid leukaemias, showed allelic loss of the chromosome 11 segment encoding Trp53. These and other data indicate strongly that the genomic regions identified as showing recurrent LOH depend on the genetic background of the mice. Overall, the results indicate a key role for a tumour suppressor gene(s) encoded in an approximately 3 cM segment on proximal chromosome 4 and provide an experimental basis for the further investigation of the functional role of candidate genes which include Pax5 and Tgfbr1.

Benchmarking using simulated clinical scenarios: a feasibility project

'Benchmarking' clinical practice and integrating such data with national guidelines offers a way of establishing standards for use in clinical governance. We report on a feasibility project for benchmarking clinical practice in one topic area (otitis media) using simulated clinical scenarios. Consistency and variations in clinical management were identified for different scenarios. Participants perceived the process likely to reflect actual practice and effect change in clinical management.

Attenuation of neurotoxicity in cortical cultures and hippocampal slices from E2F1 knockout mice

The E2F1 transcription factor modulates neuronal apoptosis induced by staurosporine, DNA damage and beta-amyloid. We demonstrate E2F1 involvement in neuronal death induced by the more physiological oxygen-glucose deprivation (OGD) in mouse cortical cultures and by anoxia in mouse hippocampal slices. E2F1(+/+) and (-/-) cultures were comparable, in that they contained similar neuronal densities, responded with similar increases in intracellular calcium concentration ([Ca(2+)]i) to glutamate receptor agonists, and showed similar NMDA receptor subunit mRNA expression levels for NR1, NR2A and NR2B. Despite these similarities, E2F1(-/-) cultures were significantly less susceptible to neuronal death than E2F1(+/+) cultures 24 and 48 h following 120-180 min of OGD. Furthermore, the absence of E2F1 significantly improved the ability of CA1 neurons in hippocampal slices to recover synaptic transmission following a transient anoxic insult in vitro. These results, along with our finding that E2F1 mRNA levels are significantly increased following OGD, support a role for E2F1 in the modulation of OGD- and anoxia-induced neuronal death. These findings are consistent with studies showing that overexpression of E2F1 in postmitotic neurons causes neuronal degeneration and the absence of E2F1 decreases infarct volume following cerebral ischemia.

Diabetic foot disorders: a clinical practice guideline. American College of Foot and Ankle Surgeons

Foot ulcerations, infections, and Charcot neuropathic osteoarthropathy are three serious foot complications of diabetes mellitus that can too frequently lead to gangrene and lower limb amputation. Consequently, foot disorders are one of the leading causes of hospitalization for persons with diabetes and can account for expenditures in the billions of dollars annually in the U.S. alone. Although not all foot complications can be prevented, dramatic reductions in their frequency have been obtained through the implementation of a multidisciplinary team approach to patient management. Using this concept, the authors present a Clinical Practice Guideline for diabetic foot disorders based on currently available evidence. The underlying pathophysiology and treatment of diabetic foot ulcers, infections, and the diabetic Charcot foot are thoroughly reviewed. Although these guidelines cannot and should not dictate the standard of care for all affected patients, they are intended to provide evidence-based guidance for general patterns of practice. The goal of a major reduction in diabetic limb amputations is certainly possible if these concepts are embraced and incorporated into patient management protocols.

Changes in plasma progesterone, estrogen, and testosterone concentrations throughout the reproductive cycle in female viviparous blue-tongued skinks, Tiliqua nigrolutea (Scincidae), in Tasmania

Changes in mean plasma concentrations of progesterone (P4), estrogen (E), and testosterone (T) in a captive population of female viviparous skinks, Tiliqua nigrolutea, were examined. Reproductively active and quiescent individuals were present in the population concurrently, allowing a comparison between these two conditions. Mean plasma progesterone concentrations were basal (1-2 ng ml(-1)) until the start of gestation and peaked in the second trimester (12.7 +/- 1.27 ng ml(-1)), before falling significantly prior to parturition. An increase in mean plasma estrogen concentrations occurred coincident with the vitellogenic period; the mean plasma estrogen concentration peaked at 715.1 +/- 106.68 pg ml(-1) shortly before ovulation. Mean plasma testosterone concentrations in reproductively active females peaked in the periovulatory period (6.3 +/- 0.63 ng ml(-1)) and had returned to basal concentrations (<1 ng ml(-1)) 2 weeks later. Changes in mean plasma steroid concentrations were correlated with reproductive condition and are discussed in terms of potential in vivo steroid interactions and the multihormone control of reproduction.

Accuracy and modifying factors of the sonographic estimation of fetal weight in a high-risk population

There have been a number of reviews assessing the accuracy of different methods of sonographic estimation of fetal weight, without identifying any clearly superior equation. In order to optimise accuracy in a high-risk population, we decided to compare some of the most popular early equations with the newer volume-based equations, and to try and identify factors that affect the ability of these equations to estimate fetal weight accurately We collected the scan and delivery details of 192 fetuses born within one week of a sonographic estimation of fetal weight. We then applied three of the most popular equations and two newer volume-based equations to the recorded fetal biometric parameters to assess the performance of each equation overall, and under varying maternal, fetal, and scan conditions. The equations of Shepard, Hadlock A, Hadlock B and Combs produced similar results with systematic (mean) errors in the range 1.2-1.9% and random error characterised by one standard deviation in the range of 8.6-9.5%. Dudley's volume-based equation produced a significant systematic error in the form of a mean error of 7.4%, which corresponds to a mean birthweight (BW) which is 7.4% above the mean estimated fetal weight (EFW). When we stratified the study group by birthweight, Combs' equation produced significant differences in the mean error, (p < 0.00001), that ranged from a mean overestimation in fetal weight of 8.5% for babies with BW < 1000 g to a mean underestimation in fetal weight of 6.2% for babies with BW > 3000 g. Oligohydramnios resulted in a trend towards an increased mean error for all equations which was only statistically significant for Hadlock B. The equations Shepard and Hadlock A performed best in our high-risk population. They produced the smallest systematic errors across the entire study group and were not adversely affected by variations in birthweight, liquor volume, or fetal presentation. The newer, volume-based equations were disappointing, producing large systematic errors. Large random errors in all equations continue to be the Achilles' heel that limit the value of sonographic EFW.

Shared decision making observed in clinical practice: visual displays of communication sequence and patterns

The aim of the study was to examine the communication strategies of general practitioners attempting to involve patients in treatment or management decisions. This empirical data was then compared with theoretical 'competences' derived for 'shared decision making'. The subjects were four general practitioners, who taped conducted consultations with the specific intent of involving patients in the decision-making process. The consultations were transcribed, coded into skill categorizations and presented as visual display using a specifically devised sequential banding

METHOD

The empirical data from these purposively selected consultation from clinicians who are experienced in shared decision making did not match suggested theoretical frameworks. The views of patients about treatment possibilities and their preferred role in decision making were not explored. The interactions were initiated by a problem-defining phase, statements of 'equipoise' consistently appeared and the portrayal of option information was often intermingled with opportunities to allow patients to question and reflect. A decision-making stage occurred consistently after approximately 80% of the total consultation duration and arrangements were consistently made for follow-up and review. Eight of the 10 consultations took more than 11 min - these specific consultations were characterized by significant proportions of time provided for information exchange and patient interaction. The results demonstrate that some theoretical competences are not distinguishable in practice and other stages, not previously described, such as the 'portrayal of equipoise', are observed. The suggested ideal of a shared decision-making interaction will either require more time than currently allocated, or alternative strategies to enable information exchange outside the consultation.

Measuring the involvement of patients in shared decision-making: a systematic review of instruments

We wanted to determine whether research instruments exist which focus on measuring to what extent health professionals involve patients in treatment and management decisions. A systematic search and appraisal of the relevant literature was conducted by electronic searching techniques, snowball sampling and correspondence with field specialists. The instruments had to concentrate on assessing patient involvement in decision-making by observation techniques (either direct or using audio or videotaped data) and contain assessments of the core aspects of 'involvement', namely evidence of patients being involved (explicitly or implicitly) in decision-making processes, a portrayal of options and a decision-making or deferring stage. Eight instruments met the inclusion criteria. But we did not find any instruments that had been specifically designed to measure the concept of 'involving patients' in decisions. The results reveal that little attention has been given to a detailed assessment of the processes of patient involvement in decision-making. The existing instrumentation only includes these concepts as sub-units within broader assessments, and does not allow the construct of patient involvement to be measured accurately. Instruments developed to measure 'patient-centeredness' are unable to provide enough focus on 'involvement' because of their attempt to cover so many dimensions. The concept of patient involvement (shared decision-making; informed collaborative choice) is emerging in the literature and requires an accurate method of assessment.

Diabetic foot disorders. A clinical practice guideline. For the American College of Foot and Ankle Surgeons and the American College of Foot and Ankle Orthopedics and Medicine

Foot ulcerations, infections, and Charcot neuropathic osteoarthropathy are three serious foot complications of diabetes mellitus that can too frequently lead to gangrene and lower limb amputation. Consequently, foot disorders are one of the leading causes of hospitalization for persons with diabetes and can account for expenditures in the billions of dollars annually in the U.S. alone. Although not all foot complications can be prevented, dramatic reductions in their frequency have been obtained through the implementation of a multidisciplinary team approach to patient management. Using this concept, the authors present a Clinical Practice Guideline for diabetic foot disorders based on currently available evidence. The underlying pathophysiology and treatment of diabetic foot ulcers, infections, and the diabetic Charcot foot are thoroughly reviewed. Although these guidelines cannot and should not dictate the standard of care for all affected patients, they are intended to provide evidence-based guidance for general patterns of practice. The goal of a major reduction in diabetic limb amputations is certainly possible if these concepts are embraced and incorporated into patient management protocols.