Severity of Dementia and Survival in Patients Diagnosed with Colorectal Cancer: A National Cohort Study in England and Wales.

AIMS: There is little evidence about the survival of patients with colorectal cancer (CRC) also diagnosed with dementia. We quantified dementia severity and estimated how it is associated with 2-year overall survival. MATERIALS AND METHODS: Records of patients aged 65 years or older diagnosed with CRC in England and Wales were identified. A novel proxy for dementia severity combined dementia diagnosis in administrative hospital data with Eastern Cooperative Oncology Group performance status. Cox regression was used to estimate hazard ratios with and without risk adjustment. RESULTS: In total, 4033 of 105 250 CRC patients (3.8%) had dementia recorded. Two-year survival decreased with increasing dementia severity from 65.4% without dementia, 53.5% with mild dementia, 33.0% with moderate dementia to 16.5% with severe dementia (hazard ratio comparing severe with no dementia: 2.97; 95% confidence interval 2.79, 3.16). Risk adjustment for comorbidity and cancer stage reduced this association slightly (hazard ratio 2.52; 95% confidence interval 2.37, 2.68) and additional adjustment for treatment factors reduced it further (hazard ratio 1.60; 95% confidence interval 1.50, 1.70). CONCLUSIONS: Survival of CRC patients varied strongly according to dementia severity, suggesting that a 'one-size-fits-all' policy for the care of CRC patients with dementia is not appropriate. Comprehensive assessment of cancer patients with dementia that considers dementia severity is essential in a shared decision-making process that ensures patients receive the most appropriate treatment for their individual needs and preferences.

Determinants of Variation in the Use of Adjuvant Chemotherapy for Stage III Colon Cancer in England.

AIMS: Adjuvant chemotherapy (ACT) for stage III colon cancer is well-established. This study aimed to explore the determinants of ACT use and between-hospital variation within the English National Health Service (NHS). MATERIALS AND METHODS: In total, 11 932 patients (diagnosed 2014-2017) with pathological stage III colon cancer in the English NHS were identified from the National Bowel Cancer Audit. Records were linked to Systemic Anti-Cancer Therapy and Hospital Episode Statistics databases. Multi-level logistic regression analyses were carried out to estimate independent factors for ACT use, including age, sex, deprivation, comorbidities, performance status, American Society of Anaesthesiologists (ASA) grade, surgical urgency, surgical access, TNM staging, readmission and hospital-level factors (university teaching hospital, on-site chemotherapy and high-volume centre). A random intercept was modelled for each English NHS hospital (n = 142). Between-hospital variation was explored using funnel plot methodology. Fully adjusted random-intercept models were fitted separately in young (<70 years) and elderly (≥70 years) patients and intra-class correlation coefficients estimated. RESULTS: 60.7% of patients received ACT. Age was the strongest determinant. Compared with patients aged <60 years, those aged 60-64 (adjusted odds ratio [aOR] 0.76, 95% confidence interval 0.63-0.93), 65-69 (aOR 0.63, 95% confidence interval 0.54-0.74), 70-74 (aOR 0.53, 95% confidence interval 0.44-0.62), 75-79 (aOR 0.23, 95% confidence interval 0.19-0.27) and ≥80 years (aOR 0.05, 95% confidence interval 0.04-0.06) were significantly less likely to receive ACT. With adjustment for other factors, ACT use was more likely in patients with higher socioeconomic status, fewer comorbidities, better performance status, lower ASA grade, advanced disease, elective resections, laparoscopic procedures and no unplanned readmissions. Hospital-level factors were non-significant. The observed proportions of ACT administration in the young and elderly were 46-100% (80% of hospitals 74-90%) and 10-81% (80% of hospitals 33-65%), respectively. Risk adjustment did not reduce between-hospital variation. Despite adjustment, age accounted for 9.9% (7.2-13.4%) of between-hospital variation in the elderly compared with 2.7% (1.2-5.7%) in the young. CONCLUSIONS: There is significant between-hospital variation in ACT use for stage III colon cancer, especially for older patients. Advanced age alone seems to be a greater barrier to ACT use in some hospitals.

Association between preadmission frailty and care level at discharge in older adults undergoing emergency laparotomy.

BACKGROUND: Older adults undergoing emergency abdominal surgery have significantly poorer outcomes than younger adults. For those who survive, the level of care required on discharge from hospital is unknown and such information could guide decision-making. The ELF (Emergency Laparotomy and Frailty) study aimed to determine whether preoperative frailty in older adults was associated with increased dependence at the time of discharge. METHODS: The ELF study was a UK-wide multicentre prospective cohort study of older patients (65 years or more) undergoing emergency laparotomy during March and June 2017. The objective was to establish whether preoperative frailty was associated with increased care level at discharge compared with preoperative care level. The analysis used a multilevel logistic regression adjusted for preadmission frailty, patient age, sex and care level. RESULTS: A total of 934 patients were included from 49 hospitals. Mean(s.d.) age was 76·2(6·8) years, with 57·6 per cent women; 20·2 per cent were frail. Some 37·4 per cent of older adults had an increased care level at discharge. Increasing frailty was associated with increased discharge care level, with greater predictive power than age. The adjusted odds ratio for an increase in care level was 4·48 (95 per cent c.i. 2·03 to 9·91) for apparently vulnerable patients (Clinical Frailty Score (CFS) 4), 5·94 (2·54 to 13·90) for those mildly frail (CFS 5) and 7·88 (2·97 to 20·79) for those moderately or severely frail (CFS 6 or 7), compared with patients who were fit. CONCLUSION: Over 37 per cent of older adults undergoing emergency laparotomy required increased care at discharge. Frailty scoring was a significant predictor, and should be integrated into all acute surgical units to aid shared decision-making and discharge planning.

ANTECEDENTES: Los adultos mayores sometidos a cirugía abdominal de urgencia tienen resultados significativamente peores que los adultos jóvenes. Para aquellos pacientes que sobreviven, el nivel de atención que requieren tras el alta hospitalaria se desconoce y esta información podría servir de guía en la toma de decisiones. El estudio ELF (Emergency Laparotomy and Frailty) tenía como objetivo determinar si la fragilidad preoperatoria en adultos mayores se asociaba con un aumento de la dependencia en el momento del alta. MÉTODOS: El estudio ELF era un estudio multicéntrico extenso efectuado en el Reino Unido (n = 49) que incluyó una cohorte prospectiva de 934 pacientes mayores (> 65 años) sometidos a laparotomía de urgencia durante marzo-junio de 2017. El objetivo fue establecer si la fragilidad preoperatoria aumentaba el nivel de asistencia en el momento del alta en comparación con el nivel de asistencia preoperatorio. Para el análisis se utilizó una regresión logística multinivel ajustada a características previas al ingreso: fragilidad, edad del paciente, género, y nivel de asistencia. RESULTADOS: La edad media de los pacientes fue 76,2 años (DE = 6,83), con un 57% de mujeres, un 20,2% de pacientes frágiles y un 37,4% de adultos mayores que presentaron un aumento en el nivel de asistencia en el momento del alta. Un aumento de la fragilidad se asoció con un incremento en el nivel de asistencia en el momento del alta (y mayor poder predictivo que la edad). La razón de oportunidades (odds ratio, OR) ajustada por el aumento del nivel de asistencia fue 4,48 (i.c. del 95% 2,03-9,91) para pacientes aparentemente vulnerables (Clinical Frailty Scale, CFS 4); 5,94 (i.c. del 95% 2,54-13,90) para aquellos ligeramente frágiles (CFS 5); y 7,88 (i.c. del 95% 2,97-20,79) para aquellos con fragilidad moderada o grave (CFS 6 and 7) en comparación con pacientes en buenas condiciones. CONCLUSIÓN: Este es el primer estudio que documenta que más del 37% de adultos mayores sometidos a laparotomía de urgencia precisaron un aumento en el nivel de asistencia en el momento del alta. La evaluación de la fragilidad debería integrarse en todas las unidades quirúrgicas de agudos para ayudar a compartir la toma de decisiones y los planes de tratamiento.

Machine learning classification of OARSI-scored human articular cartilage using magnetic resonance imaging.

OBJECTIVE: The purpose of this study is to evaluate the ability of machine learning to discriminate between magnetic resonance images (MRI) of normal and pathological human articular cartilage obtained under standard clinical conditions. METHOD: An approach to MRI classification of cartilage degradation is proposed using pattern recognition and multivariable regression in which image features from MRIs of histologically scored human articular cartilage plugs were computed using weighted neighbor distance using compound hierarchy of algorithms representing morphology (WND-CHRM). The WND-CHRM method was first applied to several clinically available MRI scan types to perform binary classification of normal and osteoarthritic osteochondral plugs based on the Osteoarthritis Research Society International (OARSI) histological system. In addition, the image features computed from WND-CHRM were used to develop a multiple linear least-squares regression model for classification and prediction of an OARSI score for each cartilage plug. RESULTS: The binary classification of normal and osteoarthritic plugs yielded results of limited quality with accuracies between 36% and 70%. However, multiple linear least-squares regression successfully predicted OARSI scores and classified plugs with accuracies as high as 86%. The present results improve upon the previously-reported accuracy of classification using average MRI signal intensities and parameter values. CONCLUSION: MRI features detected by WND-CHRM reflect cartilage degradation status as assessed by OARSI histologic grading. WND-CHRM is therefore of potential use in the clinical detection and grading of osteoarthritis.

Unusual behavior in magnesium-copper cluster matter produced by helium droplet mediated deposition.

We demonstrate the ability to produce core-shell nanoclusters of materials that typically undergo intermetallic reactions using helium droplet mediated deposition. Composite structures of magnesium and copper were produced by sequential condensation of metal vapors inside the 0.4 K helium droplet baths and then gently deposited onto a substrate for analysis. Upon deposition, the individual clusters, with diameters ∼5 nm, form a cluster material which was subsequently characterized using scanning and transmission electron microscopies. Results of this analysis reveal the following about the deposited cluster material: it is in the un-alloyed chemical state, it maintains a stable core-shell 5 nm structure at sub-monolayer quantities, and it aggregates into unreacted structures of ∼75 nm during further deposition. Surprisingly, high angle annular dark field scanning transmission electron microscopy images revealed that the copper appears to displace the magnesium at the core of the composite cluster despite magnesium being the initially condensed species within the droplet. This phenomenon was studied further using preliminary density functional theory which revealed that copper atoms, when added sequentially to magnesium clusters, penetrate into the magnesium cores.

Obesity impairs academic attainment in adolescence: findings from ALSPAC, a UK cohort.

OBJECTIVE: While being overweight or obese in adolescence may have detrimental effects on academic attainment, the evidence base is limited by reliance on cross-sectional studies with small sample sizes, failure to take account of confounders and lack of consideration of potential mediators. The present study aimed to address these limitations and examine longitudinal associations between obesity in adolescence and academic attainment. DESIGN: Associations between weight status at 11 years old and academic attainment assessed by national tests at 11, 13 and 16 years were examined in the Avon Longitudinal Study of Parents and Children. Healthy weight was defined as body mass index (BMI) Z-score <1.04; overweight as BMI Z-score 1.04-1.63; obesity as BMI Z-score ⩾1.64. PARTICIPANTS: Data from 5966 participants with objectively measured weight status were examined: 71.4% were healthy weight (1935 males; 2325 females), 13.3% overweight (372 males; 420 females) and 15.3% obese (448 males; 466 females). RESULTS: Girls obese at 11 years had lower academic attainment at 11, 13 and 16 years compared with those of a healthy weight, even after controlling for a wide range of confounders. Associations between obesity and academic attainment were less clear in boys. The potential mediating effects of depressive symptoms, intelligence quotient (IQ) and age of menarche in girls were explored, but when confounders were included, there was no strong evidence for mediation. CONCLUSIONS: For girls, obesity in adolescence has a detrimental impact on academic attainment 5 years later. Mental health, IQ and age of menarche did not mediate this relationship, suggesting that further work is required to understand the underlying mechanisms. Parents, education and public health policy makers should consider the wide reaching detrimental impact of obesity on educational outcomes in this age group.

Associations between objectively measured physical activity and academic attainment in adolescents from a UK cohort.

BACKGROUND: To test for cross-sectional (at age 11) and longitudinal associations between objectively measured free-living physical activity (PA) and academic attainment in adolescents.Method Data from 4755 participants (45% male) with valid measurement of PA (total volume and intensity) by accelerometry at age 11 from the Avon Longitudinal Study of Parents and Children (ALSPAC) was examined. Data linkage was performed with nationally administered school assessments in English, Maths and Science at ages 11, 13 and 16. RESULTS: In unadjusted models, total volume of PA predicted decreased academic attainment. After controlling for total volume of PA, percentage of time spent in moderate-vigorous intensity PA (MVPA) predicted increased performance in English assessments in both sexes, taking into account confounding variables. In Maths at 16 years, percentage of time in MVPA predicted increased performance for males (standardised ß=0.11, 95% CI 0.00 to 0.22) and females (ß=0.08, 95% CI 0.00 to 0.16). For females the percentage of time spent in MVPA at 11 years predicted increased Science scores at 11 and 16 years (ß=0.14 (95% CI 0.03 to 0.25) and 0.14 (0.07 to 0.21), respectively). The correction for regression dilution approximately doubled the standardised ß coefficients. CONCLUSIONS: Findings suggest a long-term positive impact of MVPA on academic attainment in adolescence.

Comparison of American and European practices in the management of patients with primary immunodeficiencies.

Primary immunodeficiency diseases (PIDs) comprise a heterogeneous group of rare disorders. This study was devised in order to compare management of these diseases in the northern hemisphere, given the variability of practice among clinicians in North America. The members of two international societies for clinical immunologists were asked about their management protocols in relation to their PID practice. An anonymous internet questionnaire, used previously for a survey of the American Academy of Allergy, Asthma and Immunology (AAAAI), was offered to all full members of the European Society for Immunodeficiency (ESID). The replies were analysed in three groups, according to the proportion of PID patients in the practice of each respondent; this resulted in two groups from North America and one from Europe. The 123 responses from ESID members (23·7%) were, in the majority, very similar to those of AAAAI respondents, with > 10% of their practice devoted to primary immunodeficiency. There were major differences between the responses of these two groups and those of the general AAAAI respondents whose clinical practice was composed of < 10% of PID patients. These differences included the routine use of intravenous immunoglobulin therapy (IVIg) for particular types of PIDs, initial levels of IVIg doses, dosing intervals, routine use of prophylactic antibiotics, perceptions of the usefulness of subcutaneous immunoglobulin therapy (SCIg) and of the risk to patients' health of policies adopted by health-care funders. Differences in practice were identified and are discussed in terms of methods of health-care provision, which suggest future studies for ensuring continuation of appropriate levels of immunoglobulin replacement therapies.

SnapShot: Visualization to Propel Ice Hockey Analytics.

Sports analysts live in a world of dynamic games flattened into tables of numbers, divorced from the rinks, pitches, and courts where they were generated. Currently, these professional analysts use R, Stata, SAS, and other statistical software packages for uncovering insights from game data. Quantitative sports consultants seek a competitive advantage both for their clients and for themselves as analytics becomes increasingly valued by teams, clubs, and squads. In order for the information visualization community to support the members of this blossoming industry, it must recognize where and how visualization can enhance the existing analytical workflow. In this paper, we identify three primary stages of today's sports analyst's routine where visualization can be beneficially integrated: 1) exploring a dataspace; 2) sharing hypotheses with internal colleagues; and 3) communicating findings to stakeholders.Working closely with professional ice hockey analysts, we designed and built SnapShot, a system to integrate visualization into the hockey intelligence gathering process. SnapShot employs a variety of information visualization techniques to display shot data, yet given the importance of a specific hockey statistic, shot length, we introduce a technique, the radial heat map. Through a user study, we received encouraging feedback from several professional analysts, both independent consultants and professional team personnel.

Population prevalence of diagnosed primary immunodeficiency diseases in the United States.

RATIONALE: Although health surveys are routinely used to estimate the population incidence and prevalence of many chronic and acute conditions in the U.S. population, they have infrequently been used for "rare" conditions such as primary immunodeficiency diseases (PID). Accurate prevalence measures are needed to separate the truly rare condition from those that primary care doctors are likely to see in their practices today, if early diagnosis and treatment are to be achieved. METHODS: A national probability sample of 10,000 households was sampled by random digit dialing and screened by telephone to identify how many of the nearly 27,000 household members had been diagnosed with a PID. RESULTS: A total of 23 household members in 18 households were reported with a specific diagnosis for PID (CVID, IgA, IgG, XLA, SCID, CGD), whereas additional cases were reported as a PID without a confirmatory diagnosis. These findings suggest a population prevalence of diagnosed PID in the United States at approximately 1 in 1,200 persons. CONCLUSIONS: Diagnoses of PID in the United States are far more common than suggested in the literature.

Delayed chromosome changes in gamma-irradiated normal and Li-Fraumeni fibroblasts.

Knockout mice with only one Trp53 allele (+/- genotype) are highly susceptible to radiation-induced cancers, possibly through numerical chromosome changes. Patients with the Li-Fraumeni syndrome, having heterozygous TP53 germline mutations (+/mut genotype), are also susceptible to spontaneous and radiogenic cancers. We have investigated the susceptibility of six Li-Fraumeni syndrome +/mut and six normal fibroblast strains to induced numerical and unstable structural aberrations at six population doublings after exposure to 3 or 6 Gy gamma rays. Four of the irradiated Li-Fraumeni syndrome strains showed small increases in both aberration types, similar to those seen in the normal strains. In two irradiated Li-Fraumeni syndrome strains, there were high levels of induced structural changes, and one of these showed a modest increase in hyperploidy. We suggest that enhanced sensitivity to delayed radiation-induced chromosome changes in Li-Fraumeni syndrome cells requires other genetic alterations in addition to TP53 heterozygosity, apparently in contrast to the situation in Trp53 heterozygous null mice. If such additional alterations occur in vivo in Li-Fraumeni syndrome patients, they may predispose them to radiogenic cancers, mainly through enhanced structural rather than numerical chromosome changes. Our findings raise questions about the validity of quantitative extrapolation of cytogenetic data from Trp53-defective mice to radiogenic cancer risk in humans.

The relationship between radiation-induced G(1)arrest and chromosome aberrations in Li-Fraumeni fibroblasts with or without germline TP53 mutations.

We previously showed that cultured fibroblasts from patients with the cancer-prone Li-Fraumeni (LF) syndrome, having heterozygous germline TP53 mutations, sustain less ionizing radiation-induced permanent G(1)arrest than normal fibroblasts. In contrast, fibroblast strains from LF patients without TP53 mutations showed normal G(1)arrest. We have now investigated the relationship between the extent of G(1)arrest and the level of structural chromosome damage (mainly dicentrics, rings and acentric fragments) in cells at their first mitosis after G(1)irradiation, in 9 LF strains with TP53 mutations, 6 without TP53 mutations and 7 normal strains. Average levels of damage in the mutant strains were 50% higher than in normals, whereas in non-mutant LF strains they were 100% higher. DNA double strand breaks (dsb) are known to act as a signal for p53-dependent G(1)arrest and to be the lesions from which chromosome aberrations arise. These results suggest that a minimal level of dsb is required before the signal for arrest is activated and that p53-defective cells have a higher signal threshold than p53-proficient cells. Dsb that do not cause G(1)blockage can progress to mitosis and appear as simple deletions or interact to form exchange aberrations. The elevated levels in the non-mutant strains may arise from defects in the extent or accuracy of dsb repair. In LF cells with or without TP53 mutations, the reduced capacity to eliminate or repair chromosomal damage of the type induced by ionising radiation, may contribute to cancer predisposition in this syndrome.

Chromosome instability in fibroblasts derived from Li-Fraumeni syndrome families without TP53 mutations.

The mean in vitro lifespan of dermal fibroblast strains derived from cancer-affected individuals belonging to families conforming to the classical Li-Fraumeni-syndrome or the Li-Fraumeni-like syndrome (LF strains), but in whom no TP53 mutation has been found, was not significantly different to that of normal strains. This was in contrast to LF strains that carry TP53 mutations. Cytogenetic observations of numerical and structural chromosome abnormalities were made on Giemsa stained metaphases prepared at different times during the lifespan of strains. Five strains from different LF families showed significantly increased frequencies of abnormal cells during the last 10% of their lifetime compared with seven normal strains and three other LF strains fell outside the normal range but did not reach significance. Two LF strains fell within the normal range indicating heterogeneity of the phenotype in this subset of LF fibroblasts. Numerical aberrations were the major aberration type observed. These observations of genetic instability are similar, but generally less strongly expressed, to those seen in LF strains with TP53 mutations. The basis for genetic instability in LF strains without TP53 mutations is not known, but appears not to involve defects in either the G(1)checkpoint or the checkpoint kinase hChk2.

Association of Zollinger-Ellison syndrome with pancreatitis: report of five cases.

In a retrospective analysis, five cases of Zollinger-Ellison syndrome were found in a typical urban inner-city teaching hospital. Chronic alcohol abuse and heavy smoking characterized these patients, and four of them also had pancreatitis, suggesting an association of gastrin-producing tumors and pancreatic inflammation. Ductal obstruction by neuroendocrine tumors has been reported to cause pancreatitis in a few cases. In this analysis, however, a nonobstructive gastrinoma was the surgical diagnosis in three patients, and it was suggested by imaging studies in the two other cases. The potential other pathomechanisms for a dual cause-effect relationship of gastrinoma and pancreatitis are discussed.

Genomic alterations associated with loss of heterozygosity for TP53 in Li-Fraumeni syndrome fibroblasts.

Studies of Li-Fraumeni syndrome fibroblasts heterozygous for germline TP53 mutations have shown that loss of heterozygosity (LOH) occurs during passaging and is associated with genomic instability, such as chromosomal aberrations and aneuploidy to investigate the genomic changes associated with LOH in Li-Fraumeni (LF) fibroblasts, we have analysed cell strains at increasing population doublings (PD) using Comparative Genomic Hybridization (CGH). We have looked at three groups of cell strains: LF mutation-carrying strains which showed LOH for TP53, LF mutation-carrying strains which did not show LOH, and strains from normal individuals. Using CGH, we have detected loss of distinct chromosomal regions associated with LOH in 4 out of 5 mutation-carrying strains. In particular we have found loss of chromosomal regions containing genes involved in cell cycle control or senescence, including loss of 9p and 17p in these strains. Other recurrent changes included loss of chromosomes 4q and 6q, regions shown to contain one or more tumour suppressor genes. No genomic alterations were detected at cumulative PD in the normal strains or in the LF mutation-carrying strains which did not show LOH for TP53. We have also analysed the three groups of strains for microsatellite instability and somatic TP53 mutations, and have found genetic alterations in only one strain.

Radiation-induced G1 arrest is not defective in fibroblasts from Li-Fraumeni families without TP53 mutations.

Radiation-induced G1 arrest was studied in four classes of early passage skin fibroblasts comprising 12 normals, 12 heterozygous (mut/wt) TP53 mutation-carriers, two homozygous (mut/-) TP53 mutation-carriers and 16 strains from nine Li-Fraumeni syndrome or Li-Fraumeni-like families in which no TP53 mutation has been found, despite sequencing of all exons, exon-intron boundaries, 3' and 5' untranslated regions and promoter regions. In an assay of p53 allelic expression in yeast, cDNAs from these non-mutation strains behaved as wild-type p53. Using two different assays, we found G1 arrest was reduced in heterozygous strains with mis-sense mutations and one truncation mutation, when compared to the range established for the normal cells. Heterozygous strains with mutations at splice sites behaved like normal cells, whilst homozygous (mut/-) strains showed either extremely reduced, or no, arrest. Strains from all nine non-mutation families gave responses within the normal range. Exceptions to the previously reported inverse correlation between G1 arrest and clonogenic radiation resistance were observed, indicating that these phenotypes are not strictly interdependent.

Lower extremity preference during gross and fine motor skills performed in sitting and standing postures.

The evaluation of lower limb preference in physical therapy practice is critical in order for the clinician to assist patients with functional retraining tasks. No studies in the physical therapy literature present a systematic approach to determine the criteria needed to identify the preferred limb. This research was designed to present a series of tests for effectiveness in determining limb preference. The purpose of this study was to determine whether lower limb preference existed in a group of recreationally athletic women when performing either stability or dynamic skills with the lower extremities while sitting or standing. The relationship of such a preference to handedness was also determined. Forty female recreational athletes, 20 right-handed subjects and 20 left-handed subjects, who ranged in age from 21 to 35 years, participated in this study. Subjects performed three repetitions of the following tests in both sitting and standing: kick a ball, swing a leg over a box, pick up a marble with the toes, and trace a triangle with the toes. The subjects were also asked to stand on one leg. The order of performing the tests was randomized. The results indicated that right-handed subjects performed activities more consistently with one lower extremity when compared with left-handed subjects, regardless of posture (sitting or standing). The difference in limb choice between right- and left-handed subjects was significant for all activities (p < .05). The considerable sensitivity of foot and leg performance following neurological insult renders the assessment of foot and leg preference very important for purposes of clinical rehabilitation.

Genetic and functional studies of a germline TP53 splicing mutation in a Li-Fraumeni-like family.

We report an extensive Li-Fraumeni-like family in which there is an unusual spectrum of tumours at relatively late onset. A germline TP53 splice donor mutation in exon 4 is present in all affected family members available for testing. The mutation abolishes correct splicing of intron 4 and techniques of RT-PCR have identified three different aberrant transcripts from the mutant TP53 allele. Using the yeast functional assay to analyse transcripts in cells from a number of family members with the mutant allele, TP53 appears wild-type. Functional studies have been carried out on cells from patients with and without cancer who carry the germline mutation, and on cells from unaffected individuals from the same family who do not carry the mutation. Using a number of functional endpoints known to distinguish between cells carrying mutant or wild-type TP53 alleles, we were unable to discriminate normal (wt/wt) from heterozygous (wt/mut) cells by lymphocyte apoptosis and fibroblast survival following low dose rate ionising radiation exposure. However germline mutation carriers show increased sensitivity to radiation-induced chromosome damage in the G2 phase of the cell cycle, and decreased transient and permanent G1 arrest. These studies demonstrate the importance of fully characterising the effects of TP53 germline mutations, and may explain some of the phenotypic features of this family.

Chromosome instability is a predominant trait of fibroblasts from Li-Fraumeni families.

Previous work has indicated a role for p53 in cell cycle control, genomic stability and cellular responses to DNA-damaging agents. However, few data are available for human fibroblasts heterozygous for defined germline mutations in TP53. We report studies on 25 strains derived from 12 families with Li-Fraumeni syndrome (LFS) and 18 strains from normal volunteers. The families include three that are classical LFS families, but in whom no TP53 mutation has been found. In the families with mutations, increased longevity and resistance to low-dose-rate ionizing radiation showed a statistically significant association with the presence of TP53 mutations. However, not all heterozygotes had increased longevity or were radioresistant, and fibroblasts from cancer-affected members of LFS families without TP53 mutations showed no significant increase in either of these end points. In contrast, all mutation-carrying strains showed evidence of genomic instability, expressed as aneuploidy, and accumulated structural chromosome aberrations in up to 100% of cells, usually accompanied by loss of the wild-type TP53 allele, immediately before senescence. Levels of aneuploidy higher than in normal cells were also observed in fibroblasts from families without TP53 mutations, suggesting that chromosome instability is a major factor in determining the cancer proneness of these families.