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Biomedical subjects

D Rowley

Publications and source records attributed to D Rowley.

At least 19 recordsLinked to original sources
PubMed2006

Development of a rating system for surgeons' non-technical skills.

BACKGROUND: Analyses of adverse events in surgery reveal that many underlying causes are behavioural, such as communication failure, rather than technical. Non-technical (i.e. cognitive and interpersonal) skills are not addressed explicitly in surgical training. However, surgeons need to demonstrate these skills, which underpin their technical excellence, to maximise patient safety in the operating theatre. This paper describes the method used to identify surgeons' non-technical skills, and the development of a skills taxonomy and behavioural rating system to structure observation and feedback in surgical training. METHODS: Cognitive task analyses (critical incident interviews) were conducted with 27 consultant surgeons in general, cardiac and orthopaedic surgery. The interviews were coded and a multidisciplinary group of surgeons and psychologists used an iterative process to develop a skills taxonomy. This was supported by data gathered from an attitude survey, literature review, analysis of surgical mortality reports and observations in theatre. RESULTS: Five categories of non-technical skills were identified, including situation awareness, decision making, task management, leadership and communication and teamwork. This provided a structure for a prototype skill taxonomy (v1.1), which comprised 14 non-technical skill elements. Observable behaviours (markers) indicative of good and poor performance were developed for each element by 16 consultant surgeons to form a prototype behaviour rating system. CONCLUSIONS: The prototype skills taxonomy and behaviour rating system are grounded empirically in surgery. The reliability of the system is currently being tested using standardised scenarios. If this evaluation proves successful, the system could be used to structure feedback and guide non-technical skills training.

Consultants↗
PubMed2001

In vitro dorsal root ganglia and human prostate cell line interaction: redefining perineural invasion in prostate cancer.

BACKGROUND: Little is understood regarding mechanisms of perineural invasion in prostate cancer progression. We present a novel model system and data that indicate perineural invasion is an active, specific, and reciprocal interaction between nerves and prostate cancer cells. METHODS: Mouse dorsal root ganglia (DRG) and human prostate cancer cells (Du-145, LNCaP, PC3) and stromal cells (HTS-40F) were co-cultured in Matrigel matrix. Control cultures consisted of prostate cancer and stromal cells only and DRG only. Neurite outgrowth, cell colony growth, neurite-colony contact, and retrograde extension were quantitated with dark phase microscopy and image analysis (Optimas 6.1). RESULTS: Directional outgrowth of neurites was observed projecting into DU-145 colonies within 24 hr of co-culture. Cultures with the greatest number of DU-145 cells recruited significantly more neurites and established contact earlier, indicating this process was cell-seeding density dependent. Once neurite/DU-145 cell contact was established neurite growth diminished, suggesting an active neurite recruitment by DU-145 cells. Subsequent to neurite contact, DU-145 cells migrated along neurites in a retrograde fashion into the nerve/ganglion of origin (retrograde extension) establishing perineural invasion. In addition to perineural invasion, DU-145 colony growth was elevated in DRG co-cultures relative to DU-145-only control cell cultures. Similarly, the degree of neurite outgrowth was elevated in DRG-cell co-cultures relative to DRG-only control cultures. The same observations were made with LNCaP and PC3 cells, but interactions between stromal cells and nerves were not found. CONCLUSIONS: This study shows the utility of the prostate cancer/DRG in vitro system to study specific mechanism of prostate cancer cell-nerve interaction. Moreover, these data suggest that perineural invasion mechanisms involve active and reciprocal interactions between carcinoma cells and adjacent nerve/ganglions in prostate cancer progression.

Animals↗
PubMed2001

Role of TGF-beta in immune-evasion of cancer.

One of the major obstacles in tumor-immunology is the outgrowth of malignant tumors despite their immunogenicity and recognition by the immune-system. Multiple mechanisms for this phenomenon have been proposed. We review the possible involvement of transforming growth factor beta (TGF-beta) in this context. TGF-beta is a cytokine with pleiotropic functions, involved in multiple physiologic processes including immunoregulation. Immune elimination of most cancers ultimately depends on cytolytic T cells (CTL). We propose a mechanism of specific suppression of cytolytic T cell (CTL)-responses mediated through immunoglobulin-bound TGF-beta (IgG-TGF-beta), secreted by activated B cells, and a cell of myeloid origin. This mononuclear "Veto" cell presumably binds IgG-TGF-beta through Fc-receptors and activates latent TGF-beta. The suggestion that B cell responses can inhibit tumor rejection is supported by observations in B cell-deficient mice. Ways for enhancing effective cancer immunity by interfering with the network of interactions involving IgG-TGF-beta are discussed.

Animals↗
PubMed2001

Self-efficacy and goal importance in the prediction of physical disability in people following hospitalization: a prospective study.

OBJECTIVES: This prospective study evaluates the role of self-efficacy and goal importance in predicting decreases in disability in activities of everyday living. METHOD: Disability, self-efficacy and goal importance were each assessed before and at 3 and 9 months after participants underwent joint replacement surgery. RESULTS: Disability had decreased at 3 and 9 months post-surgery assessments. Self-efficacy beliefs were higher at 3 and 9 months following surgery while goal importance was increased at 9 months but not at 3 months. Medical variables and prior disability predicted disability at 3 months. Social-cognitive variables did not contribute to the prediction of 3 months disability. Pre-surgery goal importance and self-efficacy at 3 months were independent predictors of disability at 9 months after controlling for pre-surgery and 3 months disability. Evidence also suggested that goal importance and self-efficacy interacted to predict levels of disability at 9 months following surgery. CONCLUSIONS: The findings demonstrate that recovery is governed not solely by medical phenomena but also by psychological variables and suggest that modification of these variables may have an impact on recovery outcomes. Moreover, attention should be paid to the timing of such intervention and to the length of follow-up.

Journal Article↗
PubMed2000

Sequence and analysis of chromosome 1 of the plant Arabidopsis thaliana.

The genome of the flowering plant Arabidopsis thaliana has five chromosomes. Here we report the sequence of the largest, chromosome 1, in two contigs of around 14.2 and 14.6 megabases. The contigs extend from the telomeres to the centromeric borders, regions rich in transposons, retrotransposons and repetitive elements such as the 180-base-pair repeat. The chromosome represents 25% of the genome and contains about 6,850 open reading frames, 236 transfer RNAs (tRNAs) and 12 small nuclear RNAs. There are two clusters of tRNA genes at different places on the chromosome. One consists of 27 tRNA(Pro) genes and the other contains 27 tandem repeats of tRNA(Tyr)-tRNA(Tyr)-tRNA(Ser) genes. Chromosome 1 contains about 300 gene families with clustered duplications. There are also many repeat elements, representing 8% of the sequence.

Arabidopsis↗
PubMed1999

Mechanism of inhibition of a poxvirus topoisomerase by the marine natural product sansalvamide A.

At present no antiviral agents are available for treatment of infection by the pathogenic poxvirus molluscum contagiosum virus (MCV). Here we report the identification and characterization of an inhibitor active against the virus-encoded type-1 topoisomerase, an enzyme likely to be required for MCV replication. We screened a library of marine extracts and natural products from microorganisms using MCV topoisomerase assays in vitro. The cyclic depsipeptide sansalvamide A was found to inhibit topoisomerase-catalyzed DNA relaxation. Sansalvamide A was inactive against two other DNA-modifying enzymes tested as a counterscreen. Assays of discrete steps in the topoisomerase reaction cycle revealed that sansalvamide A inhibited DNA binding and thereby covalent complex formation, but not resealing of a DNA nick in a preformed covalent complex. Sansalvamide A also inhibits DNA binding by the isolated catalytic domain, thereby specifying the part of the protein sensitive to sansalvamide A. These data specify the mechanism by which sansalvamide A inhibits MCV topoisomerase. Cyclic depsipeptides related to sansalvamide A represent a potentially promising chemical family for development of anti-MCV agents.

Binding Sites↗
PubMed1998

Postneonatal mortality surveillance--United States, 1980-1994.

PROBLEM/CONDITION: This report contains public health surveillance data that describe trends in postneonatal mortality (PNM) and that update information published in 1991. REPORTING PERIOD COVERED: 1980-1994. DESCRIPTION OF SYSTEM: National death certificate data characterizing PNM were reported by hospital physicians, coroners, and medical examiners. Data for 1980-1994 were compiled by the National Center for Health Statistics (NCHS) and obtained from NCHS public-use mortality tapes. RESULTS: The PNM rate per 1,000 live births declined 29.8% from 4.1 in 1980 to 2.9 in 1994 (31.7% decline among white infants and 25.8% among black). Most of the decline resulted from reduced mortality from infections and sudden infant death syndrome (SIDS). The PNM ratio between blacks and whites remained steady at approximately 2.1 during 1982-1988 and gradually increased to 2.4 by 1994 [corrected]. Autopsy rates for cases of SIDS increased from 82% to approximately 95% and did not differ among black infants and white infants. The decline of PNM rates for birth defects was greater for white infants than for black infants. The racial gap in PNM rates widened regionally during the study period, except in the South and the Northeast where ratios remained stable. In 1994, the largest gap persisted in the north-central region followed by the West and Northeast. INTERPRETATION: In 1994 as in 1980, PNM remained an important contributor to infant mortality, but nearly half of these deaths are caused by potentially preventable causes such as SIDS, infections, and injuries. The use of interventions for SIDS, birth defects, infections, and injuries can help reduce PNM and narrow the associated racial gap. ACTIONS TAKEN: This surveillance information, which will be distributed to administrators of state maternal and child health programs and to community-based organizations nationwide, will be useful in planning infant mortality reduction programs and to target PNM prevention efforts.

Black or African American↗
PubMed1998

Cognitive representations of illness and functional and affective adjustment following surgery for osteoarthritis.

A prospective investigation is described which sought to test the role of illness cognitions in determining patient responses to a surgical intervention for osteoarthritis. Illness cognitions were assessed amongst a consecutive sample of patients with osteoarthritis of the knee or hip prior to undergoing joint replacement surgery. Functional activity and depression were assessed pre-operatively, and at 3 and 9 months post surgery. At pre-operative assessment, functional activity and depression were univariately associated with the perceived consequences of osteoarthritis. Path analyses using longitudinal data demonstrated that illness cognitions had predictive value in explaining outcomes. Depression at 3 months was associated with higher pre-operative perceived control beliefs suggesting that patients who have high control pre-operatively may be at risk for temporary depressed mood in the immediate aftermath of surgery. This effect was not maintained at 9 months. Depression at 9 months was lower amongst patients who were more active at 3 months, who did not attribute their condition to wear and tear and who had higher expectations of surgery. Functional activity at 9 months was higher amongst those who did not attribute their condition to growing older and who perceived more control over symptoms. Socio-demographic variables were not associated with change in functional activity or depression over the course of surgery. The results provide support for an illness cognition approach in explaining functional activity and depression outcomes following surgery.

Adult↗
PubMed1998

Health benefits of joint replacement surgery for patients with osteoarthritis: prospective evaluation using independent assessments in Scotland.

STUDY OBJECTIVES: To determine extent of change in psychological, functional, and social health after knee and hip joint replacement surgery using independent assessments. DESIGN: Patients were recruited before surgery and interviewed preoperatively, three months after surgery, and nine months after surgery. Interviews were conducted in the patients' own homes. SETTING: Two orthopaedic surgery units in Scotland. PARTICIPANTS: A consecutive sample of 107 patients with osteoarthritis having primary replacement of the knee or hip. MAIN OUTCOME MEASURES: Assessments of depression, anxiety, pain, functional activity, informal care, and formal service utilisation were made at three time points. MAIN RESULTS: Anxiety and pain were significantly reduced and functional activity levels significantly increased after surgery. While gains in anxiety and pain reduction occurred between the preoperative and three month assessments, gains in activity were made between the three month and nine month assessments. Although pain was reduced and activity increased, levels of depression were unchanged after surgery. Patients reported need for assistance with fewer activities after surgery, but increases in the use of formal services and increases in the number of hours per week of informal support received were observed at both three month and nine month follow up. CONCLUSIONS: The main benefit of joint replacement surgery is pain relief. Gains in functional activity, particularly mobility and leisure activities are made by many patients. Paradoxically, surgery for osteoarthritis seems to act as a "gateway" to increases in formal and informal community support, which are maintained into the longer term.

Activities of Daily Living↗
PubMed1997

Hospitalizations for severe complications of pregnancy, 1987-1992.

OBJECTIVE: To compute ratios of severe pregnancy complications (the number of hospitalizations for pregnancy complications per 100 deliveries) and to examine factors associated with their prevalence. METHODS: Using population-based California hospital discharge data to estimate hospitalization ratios of pregnancy complications during 1987-1992, we defined cases by preselected pregnancy complication codes from the International Classification of Diseases, Ninth Revision, Clinical Modification, excluding induced abortions and delivery-associated complications. All hospital deliveries of liveborn or stillborn infants were included in our denominator. We examined ratios by age, race-ethnicity, payment source, total hospitalization charges, and length of hospital stay. RESULTS: There were 833,264 hospitalizations for pregnancy complications in California (25 complications per 100 deliveries), which included admissions for preterm labor (33%), genitourinary infection (16%), and pregnancy-induced hypertension (15%). Age-specific ratios were highest for women 14 years old and younger (38 per 100 deliveries) and lowest for women 25-29 years old (23 per 100 deliveries). Ratios of complications varied by race-ethnicity; black women had the highest (42 per 100 deliveries), and Asian-Pacific Islander women had the lowest (21 per 100 deliveries). Ratios were unaffected by payment source. In 1987, Medicaid charges were $118 million for 33% of the number of total hospitalizations for complications. In 1992, such Medicaid hospitalizations accounted for $356 million (49%) of the $734 million in total charges and for 183,295 (45%) of the 409,000 total hospital days. CONCLUSION: Our results showed disparities in ratios of severe complications of pregnancy by age and race-ethnicity as well as a shift of financial burden to Medicaid. These findings suggest that such complications may be reduced by identifying risk factors and targeting high-risk groups.

Adolescent↗
PubMed1996

Acquired stammering in Great Britain.

There are a growing number of reports of late onset of stammering from clinicians but a lack of data concerning the nature, aetiology and outcomes of therapy. This research attempts to replicate in Great Britain a survey of clinicians carried out in America. Clinicians completed a questionnaire on their clients with acquired stammering. Details on possible cause, speech and language characteristics, and therapeutic outcomes were compared with the American study. Results were similar in terms of aetiology and outcome measures despite reported differences in characteristics and treatment regimes offered.

Adolescent↗
PubMed1994

Predicting recovery from aphasia with connectionist networks: preliminary comparisons with multiple regression.

We trained a series of simulated neural networks with the raw scores on the Western Aphasia Battery from 91 aphasic patients. Patients were tested at 3 and at 12 months post onset. The most successful network we trained is able to predict AQ for an individual in 12 months from the raw scores at 3 months post-onset to a tolerance of + or -4.5. We then compared the relative success of a small range of trained networks to predict recovery with linear multiple regression. With the small groups of subjects involved in this preliminary study, the networks appeared to be more successful at predicting recovery.

Aged↗
PubMed1994

Selected antepartum medical complications and very-low-birthweight infants among black and white women.

This study estimated the risk of very-low-birthweight delivery among Black and White women with selected treatable antepartum medical conditions. A logistic regression model was applied to a retrospective, population-based data set identified by computerized, linked birth certificate and maternal hospital discharge records. For Black mothers, the adjusted odds ratio for very-low-birthweight delivery was statistically significant for essential hypertension and urinary tract infection. For White mothers, the adjusted odds ratio was statistically significant for essential hypertension, urinary tract infection, pregnancy-induced hypertension, and diabetes mellitus. Public policy designed to reduce the risk of very-low-birthweight delivery must include strategies for attenuating the impact of treatable antepartum medical conditions.

Adolescent↗
PubMed1994

Proceedings of "Workshop on Guidelines for Scene Investigation of Sudden Unexplained Infant Deaths"--July 12-13, 1993.

The 1992 Senate Report #102-104 and House Report #102-121 recommended that the Interagency Panel on Sudden Infant Death Syndrome (SIDS) review and establish an updated standard death scene investigation protocol for scene investigation of unexplained infant deaths. As a result of the recommendation, the Centers for Disease Control and Prevention's (CDC) Division of Reproductive Health (DRH), and the National Institute for Child Health and Human Development (NICHD) organized a workshop entitled "Workshop on Guidelines for Scene Investigation of Sudden Unexplained Infant Deaths," which was held in Rockville, Maryland, on July 12-13, 1993. This article outlines the proceedings of the workshop. The goal of the workshop was to gather information and ideas that could be used to establish guidelines which could be useful in developing a model death scene investigation protocol. It was not a goal of this workshop to produce a specific protocol during the workshop. The workshop was successful in generating a variety of information and ideas concerning the desirable attributes of a protocol including essential items of data, identification of certain training needs, specification of procedures for data collection, reporting, and quality assurance, and proposed strategies for implementation. This information can now be considered by the HHS Interagency SIDS Panel to develop specific guidelines for developing a standard scene investigation protocol for sudden unexplained infant deaths.

Autopsy↗
PubMed1992

Mortality among infants of black as compared with white college-educated parents.

BACKGROUND: In the United States, black infants are twice as likely to die as white infants; this difference reflects both black infants' higher rates of low birth weight and the higher mortality among black infants of normal birth weight. We studied mortality in infants born to college-educated parents in order to investigate this gap while controlling for sociodemographic variables. METHODS: We used the National Linked Birth and Infant Death Files for 1983 through 1985 to calculate infant mortality rates for children born to college-educated parents. The study population consisted of 865, 128 white infants and 42,230 black infants. A separate effect of birth weight was assessed by examining mortality rates before and after the exclusion of infants weighing less than 2500 g at birth (low-birth-weight infants). RESULTS: In this population, the infant mortality rate was 10.2 per 1000 live births for black infants and 5.4 per 1000 live births for white infants; the adjusted odds ratio for death among black infants was 1.82 (95 percent confidence interval, 1.64 to 2.01). The rate of low birth weight was more than twice as high among blacks (7 percent) as among whites (3 percent), although the mortality rate in this group was not higher among blacks than among whites. Black infants were three times as likely as white infants to die of causes attributable to perinatal events, including prematurity. They were no more likely to die of the sudden infant death syndrome. After the exclusion of low-birth-weight infants, the mortality rates for black and white infants were equal. CONCLUSIONS: In contrast to black infants in the general population, black infants born to college-educated parents have higher mortality rates than similar white infants only because of their higher rates of low birth weight. Black and white infants of normal birth weight have equivalent mortality rates.

Black or African American↗