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S Tucker

Publications and source records attributed to S Tucker.

At least 19 recordsLinked to original sources
PubMed2005

Spinal injuries admitted to a specialist centre over a 5-year period: a study to evaluate delayed admission.

STUDY DESIGN: Retrospective study of 432 patients admitted to our institution with a spinal injury over a 5-year period. OBJECTIVES: To present epidemiological data relating to this spinal population, reporting specifically on delayed admission and length of hospitalisation. SETTING: Royal National Orthopaedic Hospital, Stanmore, UK. METHODS: A total of 432 traumatic spinal injuries admitted between March 1998 and March 2003 were analysed with respect to age, gender, mechanism of injury, level of bony injury, neurological level (complete, incomplete and intact), Injury Severity Score (ISS), date of injury, referral and admission independently and length of hospitalisation. The delays between injury and referral (>3 days) and between referral and admission (>7 days) were correlated to the length of hospitalisation. A detailed analysis of the cause of delay at both junctures was undertaken. RESULTS: There were 322 males (average age, 38.6 years) and 110 females (average age, 41.8 years) in our study. Classification of neurological severity disclosed 108 complete injuries, 115 incomplete and 209 intact. The average time between injury and referral was 5.5 days (range 0-94), and between referral and admission was 10.7 days (range 0-130). A total of 161 patients (37%) experienced a delay between injury and referral, of whom 59 (37%) were subsequently also delayed to admission. The principal reason for delay between injury and referral was the treatment of concurrent injuries. Even patients with complete injuries (15/43) experienced delayed referral. In all, 112 patients (26%) experienced a delay between referral and admission. Principal reasons included the provision of beds (Intensive care, acute and rehabilitation) and physiological stabilisation of other injuries particularly thoracic trauma. CONCLUSIONS: Provision of beds remains the most common preventable reason for delay between referral and admission and is associated with increased hospitalisation. Early liaison with a designated spinal injuries unit, particularly those with cord injury remains vitally important.

Adult↗
PubMed2004

Clinical evaluation of idiopathic paroxysmal kinesigenic dyskinesia: new diagnostic criteria.

BACKGROUND: Paroxysmal kinesigenic dyskinesia (PKD) is a rare disorder characterized by short episodes of involuntary movement attacks triggered by sudden voluntary movements. Although a genetic basis is suspected in idiopathic cases, the gene has not been discovered. Establishing strict diagnostic criteria will help genetic studies. METHODS: The authors reviewed the clinical features of 121 affected individuals, who were referred for genetic study with a presumptive diagnosis of idiopathic PKD. RESULTS: The majority (79%) of affected subjects had a distinctive homogeneous phenotype. The authors propose the following diagnostic criteria for idiopathic PKD based on this phenotype: identified trigger for the attacks (sudden movements), short duration of attacks (<1 minute), lack of loss of consciousness or pain during attacks, antiepileptic drug responsiveness, exclusion of other organic diseases, and age at onset between 1 and 20 years if there is no family history (age at onset may be applied less stringently in those with family history). In comparing familial and sporadic cases, sporadic cases were more frequently male, and infantile convulsions were more common in the familial kindreds. Females had a higher remission rate than males. An infantile-onset group with a different set of characteristics was identified. A clear kinesigenic trigger was not elicited in all cases, antiepileptic response was not universal, and some infants had attacks while asleep. CONCLUSIONS: The diagnosis of idiopathic paroxysmal kinesigenic dyskinesia (PKD) can be made based on historical features. The correct diagnosis has implications for treatment and prognosis, and the diagnostic scheme may allow better focus in the search for the PKD gene(s).

Adolescent↗
PubMed2004

Metastatic squamous cell carcinoma in two loggerhead sea turtles Caretta caretta.

We received 2 stranded loggerhead sea turtles (Caretta caretta) with squamous cell carcinomas to necropsy. The dead turtles had been collected in Gran Canaria and Fuerteventura in April 1994 and May 1997, respectively to determine the cause of death. One turtle had 3 ulcerated lesions in the dorsal part of the neck and several irregular masses in the lungs and kidneys. Histologic examination of lesions in the skin, lungs, kidneys, and ventricular myocardium revealed neoplastic proliferation of abnormal keratinocytes. Ultrastructural examination identified the tumoral cells as epithelial cells. The second turtle had 4 lesions in the skin of the head and flippers, and several irregular masses in the lungs, liver, and kidneys. Histological examination revealed a squamous cell carcinoma with metastases to muscle tissue, liver, lungs, and kidneys. Attempts to characterize the tumoral cells by immunohistochemistry using several monoclonal and polyclonal antisera against high and low molecular weight cytokeratins from mammals, as well as vimentin and desmin, failed. Differences between reptilian keratins (mainly beta-keratins) and mammalian keratins (mainly alpha-keratins) could explain this absence of immunoreactivity. This is the first description of squamous cell carcinoma in sea turtles.

Animals↗
PubMed2003

Study group funding.

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Education, Dental, Continuing↗
PubMed2002

Assessment of prospective foodchain doses from radioactive discharges from BNFL Sellafield.

This paper presents the method used by the UK Food Standards Agency (FSA) to assess the potential impact of proposed radioactive discharges from the Sellafield nuclear site on food and determine their acceptability. It explains aspects of a cautious method that has been adopted to reflect the UK government policy and uncertainties related to people's habits with regard to food production and consumption. Two types of ingestion doses are considered in this method: 'possible' and 'probable' doses. The method is specifically applied to Sellafield discharge limits and calculated possible and probable ingestion doses are presented and discussed. Estimated critical group ingestion doses are below the dose limit and constraint set for members of the public. The method may be subject to future amendments to take account of changes in government policy and the outcome of a recent Consultative Exercise on Dose Assessments carried out by FSA. Uncertainties inherent in dose assessments are discussed and quantified wherever possible.

Animals↗
PubMed2001

Respiratory-driven lung tumor motion is independent of tumor size, tumor location, and pulmonary function.

PURPOSE: To determine whether superior-inferior lung tumor motion is predictable by tumor size or location, or pulmonary function test results. METHODS AND MATERIALS: Superior-inferior tumor motion was measured on orthogonal radiographs taken during simulation of 22 patients with inoperable lung cancer diagnosed by orthogonal radiographs. RESULTS: The tumor size averaged 5.5 +/- 3.1 cm (range 1.5-12 cm). Seven of 11 central tumors demonstrated some motion compared with 5 of 11 peripheral tumors. Four of 5 upper lobe tumors moved compared with 8 of 17 tumors that were either middle or lower lobe lesions. The mean fourth rib motion was 7.3 +/- 3.2 mm (range 2-15). The mean FeV(1) was 1.8 +/- 1.2 (range 0.55-5.33. The mean diffusing capacity of the lung for carbon monoxide was 14.0 +/- 6.5 (range 7.8-21.9). The mean total lung capacity was 6.5 +/- 1.2 (range 3.3-8.4). None of these parameters correlated with tumor motion. Although lateral tumor motion could not be consistently determined, 1 tumor moved 10 mm anterior-posteriorly. CONCLUSIONS: Lung tumors often move significantly during respiration. Tumor motion is not predictable by tumor size or location, or pulmonary function test results. Therefore, tumor motion must be measured in all patients. Measurement in three dimensions will likely be necessary to maximize the irradiated lung volumes or choose beam arrangements parallel to the major axis of motion.

Adult↗
PubMed2001

Mantle irradiation alone for pathologic stage I and II Hodgkin's disease: long-term follow-up and patterns of failure.

PURPOSE: We performed a retrospective study to determine the long-term outcome, patterns of failure, and prognostic factors for patients with pathologic Stage I or II Hodgkin's disease (HD) who were treated with mantle irradiation alone. METHODS AND MATERIALS: The medical records of 145 patients with pathologic Stage I or II supradiaphragmatic Hodgkin's disease treated with mantle irradiation alone between June 1967 and June 1991 were reviewed. Patterns of failure, overall survival (OS) rate, and progression-free survival (PFS) rate were determined. Univariate and multivariate analyses were performed to identify adverse prognostic factors for OS and PFS. The number of adverse prognostic factors per patient was counted, and a prognostic score was assigned to each patient. The log-rank test was used to compare the OS or PFS rates among patients with prognostic scores 0, 1, and 2. RESULTS: The median patient age was 27 years (range 10-66), with almost even male to female distribution. Every patient had splenectomy and negative laparotomy (LAP). Fifty-one patients had Stage I disease (IA-49, IB-2) and 94 Stage II (IIA-89, IIB-5). The histologic subtypes were nodular sclerosing in 110, mixed cellularity in 28, lymphocyte predominance in 5, lymphocyte depleted in 1, and unclassified in 1. Twelve patients with Stage II disease had >/= 3 sites of nodal involvement. Fifty-four patients had a prognostic score of 0, 70 of 1, and 21 of 2. The median follow-up time for the 109 surviving patients was 146 months (range 25-381). The 10- and 20-year actuarial OS rates for the whole group were 87.6% and 65.3%, respectively. The corresponding actuarial PFS rates were 75.3% and 74.2%, respectively. Thirty-six patients (9 Stage I, 27 Stage II) had relapses in a total of 41 sites. Failures by histology were 29 patients with nodular sclerosing, 6 with mixed cellularity, and 1 with lymphocyte predominance. Failures by sites were: trans-diaphragmatic, 22 (para-aortic nodes, 15; as the only site of progression in 12; visceral, 7; as the only site of progression in 5); within radiation field, 8; marginal miss, 8 (as the only site of failure in 2); and unknown, 3. The majority of the failures occurred within 5 years of diagnosis. Long-term side effects of radiation included cardiac complications in 30 patients, with 10- and 20-year actuarial cardiac complication rates of 12.6% and 35.1%, respectively; secondary solid tumors in 14, with 10- and 20-year actuarial rates of 2.3% and 25.7%, respectively; leukemia in 4; non- Hodgkin's lymphoma in 4, with the 10- and 20-year actuarial rates for leukemia and non-Hodgkin's lymphoma of 4.0% and 13.9%; and hypothyroidism in 38. Four adverse prognostic factors were identified for PFS: age > or = 40 years, > or = 3 sites of involvement, male sex, and constitutional symptoms. The prognostic score correlated with patients' outcome as indicated by PFS and OS rates. Patients with a prognostic score of 0 did significantly better than those with a score of 1 or 2. CONCLUSION: In this select group of patients with pathologic Stage I and II Hodgkin's disease treated with mantle irradiation alone, the OS and PFS rates at 10 and 20 years were comparable to those reported in the literature. The major pattern of disease progression was relapse below the diaphragm, therefore close surveillance of the abdomen is warranted. The prognostic score used in our series may predict the patient's outcome, and might be worth testing in a prospective trial. In our series, patients with a prognostic score of 0 had excellent long-term survival, indicating adequate treatment with mantle irradiation alone. Late complications of the treatment pose a significant threat for the patient's survival with long-term follow-up.

Adolescent↗
PubMed2001

Intracellular parasitism of macrophages by Cryptococcus neoformans.

Cryptococcus neoformans, an encapsulated fungal pathogen, causes meningoencephalitis in immunocompromised patients. Recent in vivo studies have demonstrated that C. neoformans is a facultative intracellular pathogen, as was previously suggested by in vitro studies. For survival in macrophages, C. neoformans utilizes a novel strategy for intracellular parasitism that includes the accumulation of intracellular polysaccharide in cytoplasmic vesicles. Confirmation of the fact that C. neoformans is a facultative intracellular pathogen could provide new insights into several poorly understood areas of cryptococcal pathogenesis, including mechanisms for latency and persistence and the lack of efficacy of humoral immunity. The finding that C. neoformans replicates inside macrophages in vitro in a manner similar to that observed in vivo provides an excellent system to dissect the molecular mechanisms responsible for this unique pathogenic strategy.

Animals↗
PubMed2001

Multicentric lymphoblastic lymphoma in a loggerhead sea turtle (Caretta caretta).

A juvenile female loggerhead sea turtle (Caretta caretta) stranded in Gran Canaria was submitted for necropsy. The turtle had exhibited anorexia and lethargy for 2 weeks prior to its death. At necropsy, the thymus was enlarged by two white and firm nodules. White nodules similar to those in thymus were observed in the plastron, thyroid gland, heart, aorta, left lung, spleen, liver, kidneys, stomach, and small intestine. Histopathology revealed a neoplastic proliferation of round cells identified as lymphoid cells. Ultrastructurally, the neoplastic cells were consistent with lymphoblastic cells, and viruses were not detected. The diagnosis was multicentric lymphoblastic lymphoma. This is the first report of a lymphoid neoplasm in a sea turtle.

Animals↗
PubMed1999

The genetic locus NRC-1 within chromosome 3p12 mediates tumor suppression in renal cell carcinoma independently of histological type, tumor microenvironment, and VHL mutation.

Human chromosome 3p cytogenetic abnormalities and loss of heterozygosity have been observed at high frequency in the nonpapillary form of sporadic renal cell carcinoma (RCC). The von Hippel-Lindau (VHL) gene has been identified as a tumor suppressor gene for RCC at 3p25, and functional studies as well as molecular genetic and cytogenetic analyses have suggested as many as two or three additional regions of 3p that could harbor tumor suppressor genes for sporadic RCC. We have previously functionally defined a novel genetic locus nonpapillary renal carcinoma-1 (NRC-1) within chromosome 3p12, distinct from the VHL gene, that mediates tumor suppression and rapid cell death of RCC cells in vivo. We now report the suppression of tumorigenicity of RCC cells in vivo after the transfer of a defined centric 3p fragment into different histological types of RCC. Results document the functional involvement of NRC-1 in not only different cell types of RCC (i.e., clear cell, mixed granular cell/clear cell, and sarcomatoid types) but also in papillary RCC, a less frequent histological type of RCC for which chromosome 3p LOH and genetic aberrations have only rarely been observed. We also report that the tumor suppression observed in functional genetic screens was independent of the microenvironment of the tumor, further supporting a role for NRC-1 as a more general mediator of in vivo growth control. Furthermore, this report demonstrates the first functional evidence for a VHL-independent pathway to tumorigenesis in the kidney via the genetic locus NRC-1.

Animals↗
PubMed1999

Interleukin-10 levels are often elevated in serum of adults with Hodgkin's disease and are associated with inferior failure-free survival.

BACKGROUND: Interleukin-10 (IL-10) is a pleiotropic cytokine that protects B- or T-lymphocytes and hemopoietic progenitors from apoptosis induced by doxorubicin, glucocorticoids, or deprivation of growth factors. IL-10 is also immunosupressive, and tumor cells secreting IL-10 can grow in syngeneic or allogeneic hosts, and can inhibit the generation of tumor-specific cytotoxic T cells. Hodgkin-Reed-Sternberg cells are derived from follicular center B cells and they may be latently infected by EBV. When this occurs they often express IL-10. Based on these considerations we investigated the relationship between pretreatment serum IL-10 levels and failure-free survival (FFS) in Hodgkin's disease (HD). PATIENTS AND METHODS: Untreated patients, older than 16 years, with biopsy-proven HD, were included if treated with ABVD or equivalent regimens, and if pretreatment serum was available. IL-10 levels were determined with a capture enzyme-linked immunoassay specific for cellular IL-10. RESULTS: Among healthy adult volunteers serum IL-10 levels ranged from 4.8-9.8 pg/ml (mean 7.1, standard deviation 1.5 pg/ml). Therefore levels > or = 10 pg/ml were considered elevated. We identified 101 patients with available serum. Their median age was 32 years, and 60% had B-symptoms. Ann Arbor stage was I in 4, II in 21, III in 35, and IV in 41 patients. Histology was nodular sclerosis in 74, mixed cellularity in 12, lymphocyte predominance in six, lymphocyte depletion in one, and unclassified in eight patients. Pretreatment serum IL-10 levels were elevated in 51 patients, and were higher in those with serum albumin < 3.5 g/dl, B symptoms, serum beta 2-microglobulin > or = 2.5 mg/l, anemia, and AAS III or IV. After a median follow-up of 32 months for survivors, 20 patients have progressed, and the three-year FFS of those with high vs. normal serum IL-10 was 60% +/- 9 vs. 91 +/- 9% (50% vs. 50% of the population; P = 0.004 by log-rank). Among patients with Ann Arbor stage III or IV the three-year FFS for those with high vs. normal serum IL-10 (58 vs. 42% of the population) was 57 +/- 9% vs. 92 +/- 6% (P = 0.008 by log-rank). Multivariate analysis using Cox's proportional hazards model confirmed that IL-10 was an independent variable associated with inferior FFS in this population. CONCLUSIONS: Elevation of serum IL-10 levels is frequent and is associated with inferior FFS in adults with ABVD-treated HD. This observation should be verified in other patient populations. In addition, the source and the role of IL-10 in the biology of HD should be further investigated.

Adolescent↗
PubMed1999

Enhancing psychiatric nursing practice: role of an advanced practice nurse.

In response to demands for alternative health models that deliver cost-effective quality care, one large Midwestern medical center implemented a change in their nursing practice model. The change involved the introduction of unit-based nursing leadership teams that included advanced practice nurses (APNs). This article reports the findings from an investigation that employed a case study design to evaluate the process and outcomes of integrating an APN on a psychiatric unit with experienced nurses. Data collection methods included a nursing survey (n = 34), interviews with nine randomly selected nurses, and two multidisciplinary open forums. Consistent with the staff nurses' survey ratings of important advanced practice role functions, responses from the nursing interviews and open forums suggested nurses' professional development to be the most positive outcome. Role confusion was identified as a negative outcome. Recommendations for improved integration and use of APNs in today's psychiatric health environments were identified.

Hospital Units↗
PubMed1998

The long-term efficacy of a behavioral parent training intervention for families with 2-year-olds.

The effectiveness of a behavioral parent training (BPT) intervention for improving maternal self-efficacy, maternal stress, and the quality of mother-toddler interactions has been demonstrated (Gross, Fogg, & Tucker, 1995). The 1-year follow-up of the 46 parents of toddlers (assigned to an intervention or comparison group) who participated in that study is reported. It was hypothesized that (a) BPT would lead to enduring positive changes in parenting self-efficacy, parenting stress, and parent-toddler interactions; and (b) the amount of parent participation in the intervention would be correlated with greater gains in parent-child outcomes at 1 year. All the families were retained and significant gains in maternal self-efficacy, maternal stress, and mother-child interactions were maintained. Minimal BPT effects were found for fathers. BPT dosage was related to reductions in mother critical statements and negative physical behaviors at 1-year postintervention. The findings are consistent with self-efficacy theory and support parenting self-efficacy as a target for BPT in families of young children.

Adult↗
PubMed1998

Orientation of lumbar pars defects: implications for radiological detection and surgical management.

Lateral oblique radiographs are considered important for the identification of spondylolytic lesions, but these projections will give a clear view only when the radiological beam is in the plane of the defect. We studied the variation in orientation of spondylolytic lesions on CT scans of 34 patients with 69 defects. There was a wide variation of angle: only 32% of defects were orientated within 15 degrees of the 45 degrees lateral oblique plane. Lateral oblique radiographs should not be considered as the definitive investigation for spondylolysis. We suggest that CT scans with reverse gantry angle are now more appropriate than oblique radiography for the assessment of spondylolysis. Variation in the angle of the defect may also need consideration when direct repair is being planned.

Adolescent↗
PubMed1997

Apoptosis in chronic myelogenous leukemia: studies of stage-specific differences.

In this study we compared rates of apoptosis, survival and metabolic activity from CML peripheral blood neutrophils with peripheral blood and bone marrow neutrophils from healthy volunteer donors and studied the influence of the disease stage and of cytokines including G-CSF, GM-CSF and IL-1beta on these parameters. Quantification of apoptosis by morphology, diphenylamine DNA fragmentation assay and by gel electrophoresis showed similar rates of apoptosis in chronic phase CML and normal peripheral blood neutrophils when the cells were incubated in RPMI + FCS or in serum-free medium. However, there were lower rates of apoptosis in accelerated and blast phase CML neutrophils (p < .001) and in normal bone marrow neutrophils (p < .001) compared to normal peripheral blood neutrophils (incubated in RPMI + FCS). Survival among neutrophils from chronic phase or accelerated/blast phase CML patients was significantly longer (p < 0.002 and p < 0.001, respectively) than among normal peripheral blood neutrophils but neutrophils purified from normal bone marrow had a survival rate which fell between that of normal peripheral blood and chronic phase CML patients. When the cells were incubated in RPMI + autologous sera, neutrophils from chronic phase CML patients showed markedly lower rates of apoptosis (p < 0.001) and maintained higher metabolic activities (p < 0.002) compared to normal neutrophils. G-CSF and GM-CSF were found to considerably decrease the rate of apoptosis in chronic phase CML neutrophils (p < 0.001 and p = 0.008 respectively) while IL-1beta did not show any antiapoptotic effect. It is suggested that the endogenous production of growth factors may therefore participate in delaying apoptotic cell death, during the progression of CML.

Adult↗