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S Thomas

Publications and source records attributed to S Thomas.

At least 19 recordsLinked to original sources
PubMed2007

The value of magnetic resonance imaging in our current management of ACL and meniscal injuries.

Magnetic resonance imaging (MRI) is frequently used in the diagnosis of anterior cruciate ligament (ACL) and meniscal injuries. The aim of this retrospective study was to determine the reliability and value of MRI in our management of ACL and meniscal tears. 138 patients who had undergone a MRI to confirm or refute the clinical diagnosis of an ACL or meniscal tear were identified. Those who had subsequently undergone arthroscopy were selected. MRI findings and clinical diagnosis were compared with those at arthroscopy. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and overall accuracy of clinical diagnosis and MRI were then calculated. The overall accuracy for MRI was 91, 68 and 86% for detecting ACL, medial meniscal and lateral meniscal tears, respectively. Accuracy for clinical diagnosis was 90 and 64% for ACL and meniscal tears, respectively. In contrast to other series, our results indicate a lower accuracy of MRI in detecting pathology, especially of the ACL and medial meniscus. We noted a low sensitivity, specificity and positive predictive value but a high negative predictive value rendering MRI most useful as a negative diagnostic tool. We suggest that where symptoms and clinical findings support one of these diagnoses and arthroscopic therapeutic intervention is contemplated, that MRI scanning is not always beneficial. Our current practice of requesting scans to routinely confirm the diagnosis should be altered. Unnecessary MRI scanning increases the financial burden and delays patient treatment.

Adult↗
PubMed2006

[Urinary and faecal incontinence in the elderly at home].

Urinary and faecal incontinence are a growing problem in the Dutch elderly population. Recent figures from general practice suggest an average prevalence in the over-60-year-olds of 19 and 6%, respectively. Due to an accurate system of continuous monitoring and a very high response on a non-validated but clearly-worded and short questionnaire, the reliability of these figures is most probably high. The research article is one in a series on incontinence from the same research group that studied the practical implications of urinary incontinence in the elderly. Topics published so far concerned - among others - a systematic review of the efficacy of available interventions for urinary incontinence and an in-depth study of the barriers felt by GPs regarding their familiarity with and frequency of use of these interventions. The results of these studies can easily be translated for postgraduate education. Sadly, the magnitude and quality of the knowledge base for the treatment of faecal incontinence still lags behind.

Aged↗
PubMed2006

Early enteral nutrition within 24h of colorectal surgery versus later commencement of feeding for postoperative complications.

BACKGROUND: The role of early postoperative enteral nutrition after gastrointestinal surgery is controversial. Traditional management consist of 'nil by mouth', where patients receive fluids followed by solids when tolerated. Although several trials have implicated lower incidence of septic complications and faster wound healing upon early enteral feeding, other trials have shown opposite results. The immediate advantage of caloric intake could be a faster recovery with fewer complications, to be evaluated systematically. OBJECTIVES: To evaluate whether early commencement of postoperative enteral nutrition compared to traditional management (no nutritional supply) is associated with fewer complications in patients undergoing gastrointestinal surgery SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials, PUBMED, EMBASE, and LILACS from 1979 (first RCT published) to March 2006. We manually scanned the references from the relevant articles, and consulted primary authors for additional information. SELECTION CRITERIA: We looked for randomised controlled trials (RCT's) comparing early commencement of feeding (within 24 hours) with no feeding in patients undergoing gastrointestinal surgery. Early enteral nutrition is defined as all oral intakes (i.e. registered oral intake, supplemented oral feeding) and any kind of tube feeding (gastric, duodenal or jejunal) containing caloric content. No feeding is traditional management, defined as none caloric oral intake or any kind of tube feeding before bowel function. The definition 'no nutrition' includes non caloric placebo and water. DATA COLLECTION AND ANALYSIS: The three authors independently assessed the identified trials, and extracted the relevant data using a specifically developed data extraction sheet. Primary end points of interest were: Wound infections and intraabdominal abscesses, postoperative complications such as acute myocardial infarction, postoperative thrombosis or pneumonia, anastomotic leakages, mortality, length of hospital stay, and significant adverse effects. We combined data to estimate the common relative risk of postoperative complications, and calculated the associated 95% confidence intervals. For analysis, we used fixed effects model (risk ratios to summarise the treatment effect) whenever feasible. The treatment effect on length of stay was estimated using effect size (presented as mean +/- SD). Some outcomes were not analysed but presented in a descriptive way. We used a random effects model to estimate overall risk ratio and effect size. MAIN RESULTS: We identified thirteen randomised controlled trials, with a total of 1173 patients, all undergoing gastrointestinal surgery. Individual clinical complications failed to reach statistical significance, but the direction of effect indicates that earlier feeding may reduce the risk of post surgical complications. Mortality was the only outcome showing a significant benefit, but not necessarily associated with early commencement of feeding, as the reported cause of death was anastomotic leakage, reoperation, and acute myocardial infarction. AUTHORS' CONCLUSIONS: Although non-significant results, there is no obvious advantage in keeping patients 'nil by mouth' following gastrointestinal surgery, and this review support the notion on early commencement of enteral feeding.

Colon↗
PubMed2006

Thyroid hormone insufficiency during brain development reduces parvalbumin immunoreactivity and inhibitory function in the hippocampus.

Thyroid hormones are necessary for brain development. gamma-Amino-butyric acid (GABA)ergic interneurons comprise the bulk of local inhibitory circuitry in brain, many of which contain the calcium binding protein, parvalbumin (PV). A previous report indicated that severe postnatal hypothyroidism reduces PV immunoreactivity (IR) in rat neocortex. We examined PV-IR and GABA-mediated synaptic inhibition in the hippocampus of rats deprived of thyroid hormone from gestational d 6 until weaning on postnatal d 30. Pregnant dams were exposed to propylthiouracil (0, 3, 10 ppm) via the drinking water, which decreased maternal serum T(4) by approximately 50-75% and increased TSH. At weaning, T(4) was reduced by approximately 70% in offspring in the low-dose group and fell below detectable levels in high-dose animals. PV-IR was diminished in the hippocampus and neocortex of offspring killed on postnatal d 21, an effect that could be reversed by postnatal administration of T(4). Dose-dependent decreases in the density of PV-IR neurons were observed in neocortex and hippocampus, with the dentate gyrus showing the most severe reductions (50-75% below control counts). Altered staining persisted to adulthood despite the return of thyroid hormones to control levels. Developmental cross-fostering and adult-onset deprivation studies revealed that early postnatal hormone insufficiency was required for an alteration in PV-IR. Synaptic inhibition of the perforant path-dentate gyrus synapse evaluated in adult offspring, in vivo, revealed dose-dependent reductions in paired pulse depression indicative of a suppression of GABA-mediated inhibition. These data demonstrate that moderate degrees of thyroid hormone insufficiency during the early postnatal period permanently alters interneuron expression of PV and compromises inhibitory function in the hippocampus.

Age Factors↗
PubMed2006

Evaluation of a diphtheria-tetanus-acellular pertussis-inactivated poliovirus-Haemophilus influenzae type b vaccine given concurrently with meningococcal group C conjugate vaccine at 2, 3 and 4 months of age.

BACKGROUND AND OBJECTIVE: In view of the possible introduction of diphtheria-tetanus-acellular pertussis-inactivated poliovirus-Haemophilus influenzae type b (DTaP-IPV-Hib, eg Pediacel) vaccine in the UK, a study of the immunogenicity of Pediacel when given with one of two different meningococcal group C conjugate (MCC) vaccines at 2, 3 and 4 months of age was conducted. METHODS: Randomised controlled study in 241 infants. RESULTS: Post vaccination, the proportion of infants with anti-polyribosylribitol phosphate (PRP) levels > or =0.15 microg/ml was 93.2% (95% confidence interval (CI) 86.6 to 96.7) in the Pediacel group compared with 100% (95% CI 96.4 to 100) in the diphtheria-tetanus-whole-cell pertussis-Haemophilus influenzae type b (DTwP-Hib) group. The anti-PRP response was lower in infants receiving either Pediacel or DTwP-Hib when these vaccines were given concomitantly with meningococcal group C conjugate with diphtheria-derived protein CRM(197) as conjugate protein (MCC-CRM) compared with meningococcal group C conjugate with tetanus toxoid as conjugate protein (MCC-TT). For group C meningococcus, the proportion of infants with serum bactericidal antibody (SBA) titre > or =1:8 in the Pediacel group was 99.0% compared with 100% in the DTwP-Hib group. The MCC SBA geometric mean titre (GMT) was lower in those receiving Pediacel with MCC-TT than in those receiving DTwP-Hib with MCC-TT, although all titres were well above the protective threshold. The MCC SBA GMT was similar in those receiving Pediacel and DTwP-Hib and MCC-CRM. Responses to all other vaccine components were equivalent in the two groups. CONCLUSIONS: Pediacel is immunogenic when given at 2, 3 and 4 months of age. Coadministration of MCC vaccine can influence the Hib response, and the MCC response to a tetanus conjugate can be influenced by the nature of the coadministered DTP-Hib vaccine.

Diphtheria-Tetanus-Pertussis Vaccine↗
PubMed2006

Anaemia in diabetic patients with chronic kidney disease--prevalence and predictors.

AIMS/HYPOTHESIS: We investigated the relationship between haemoglobin (Hb) and diabetes in patients with renal disease. SUBJECTS, MATERIALS AND METHODS: All adult patients with stable chronic kidney disease attending renal or diabetic outpatient clinics in a six-month period were identified. Patients' notes and electronic patient records were used to build a comprehensive biochemical and clinical database. Results were analysed for the predictors of Hb, the severity of anaemia in both groups and the relative impact of diabetes on haemoglobin and anaemia. RESULTS: The study group consisted of 468 patients, of whom 204 had diabetes and 264 did not. At every level of renal function haemoglobin levels were lower by an average of 10 g/l in subjects with diabetes than in those without. Likewise, anaemia was found to occur at an earlier stage of chronic kidney disease (and to be of greater severity) in diabetic patients. Independent predictors of haemoglobin included female sex, diabetes, renal function and serum albumin, with diabetes and renal function being the greatest predictors. Multiple logistic regression showed that patients with diabetes had an odds ratio of 4 for being anaemic. Had we used an estimated GFR of less than 60 ml/min to trigger investigation of anaemia, we would have detected 85% of anaemic patients. CONCLUSIONS/INTERPRETATION: Anaemia is frequently found in diabetic patients with renal disease, occurs earlier and is more severe than in similar but non-diabetic subjects. In contrast to previous publications, our findings suggest that anaemia is prevalent at the earliest stages of chronic kidney disease. We advocate an estimated GFR threshold of <60 ml/min to trigger investigation for anaemia in diabetic subjects.

Adult↗
PubMed2006

On the association and structure of radicals derived from dipyridil[3,2-a:2'3'-c]phenazine. Contrast between the electrochemical, radiolytic, and photochemical reduction processes.

The reduction of dipyridil[3,2-a:2'3'-c]phenazine, dppz, by pulse radiolytically generated e(-)(sol) or by the reaction of the dppz excited states with electron donors produces the radical dppzH(.). The dimer radical, (dppz)(2)H(.), exists in equilibrium with dppz with an association constant, K = 10(3) M(-1). The rate constant for the reaction of dppzH(.) with dppz is k = 4.3 x 10(6) M(-1) s(-1). DFT calculations on the structures of dppzH(.) and the doubly reduced and doubly protonated dppzH(2) rendered a planar structure for the former species and a bent one for the latter.

Journal Article↗
PubMed2006

[Dealing with medically unexplained symptoms in general practice: from irritation to 'the tricks of the trade'].

Patients with medically unexplained symptoms pose a problem for medical professionals. Doctors usually lack tools to handle these complaints adequately. Over the past decades much research has been done in the areas of classification and intervention both in general practice and in specialist care. If the doctor responds to the patient by offering to prescribe medicinal symptom relief, the first step into the vicious circle is taken. The patient is polite enough to try the medication but when it does not help, returns to the doctor. If the doctor continues to think along somatic lines the phenomenon known as iatrogenically enforced somatic fixation may arise. The main development in intervention stems from cognitive behavioural therapy, which is now considered the gold standard for all patients, regardless of their symptoms. In the Netherlands, a postgraduate course has been developed to implement the fundamentals of this approach into general practice. On this course, the doctor learns not to be deterred by the somatizing patient and to effectively close off their somatic treatment trajectory. He or she teaches the patient to look at the situation from a new perspective and instead of being preoccupied with what is not functioning well to concentrate on training those activities which can be carried out effectively. This shift in emphasis can help to cause the preoccupation of the patient to slowly disappear. Initial results are encouraging: both patients and general practitioners have responded favourably.

Cognitive Behavioral Therapy↗
PubMed2006

Interchangeability of Hepatitis A boosters, Avaxim and Vaqta, in healthy adults following a primary dose of the combined typhoid/Hepatitis A vaccine Viatim.

This study investigated the suitability of Avaxim and Vaqta as Hepatitis A booster vaccines 6 months after priming with the combined Hepatitis A/typhoid vaccine, Viatim. One hundred and twenty adults were randomly assigned to one of the three groups. Group A (reference group) received Avaxim then Avaxim (n = 40), Group B received Viatim then Avaxim (n = 41) and Group C received Viatim then Vaqta (n = 39). One month after booster vaccination, anti-Hepatitis A virus (anti-HAV) antibodies geometric mean concentrations (GMC) of subjects primed with Viatim were non-inferior to the group primed and boosted with the monovalent Hepatitis A vaccine Avaxim. Anti-Salmonella typhi capsular polysaccharide virulence antigen (anti-Vi) GMCs in groups primed with Viatim were protective and all vaccines were well-tolerated. Therefore, Viatim may be used as a primary HAV vaccine with either Avaxim or Vaqta as Hepatitis A boosters and it will provide the same protection as two doses of Avaxim.

Adult↗
PubMed2006

Surface-enhanced resonance Raman scattering and density functional calculations of hemicyanine adsorbed on colloidal silver surface.

Resonance Raman (RR) and surface-enhanced resonance Raman scattering (SERRS) of 4'-(N,N'-dimethylaminostyryl)-4-propylpyridinium bromide (hemicyanine, HC dye) in acetonitrile solution and on a colloidal silver surface have been investigated. The structure of the dye in the ground (S0) and excited (S1) electronic states was optimized using density functional calculations along with the B3LYP and the configuration interaction with the singlet excitation (CIS) methods, respectively, using the 6-31G basis set. The vibrational frequencies of the molecule were computed at the optimized geometry and compared with the observed Raman bands. A complete normal-mode analysis has been carried out because it is essential for the accurate assignment of the vibrational spectra. From the observed enhancement along various in-plane and out-of-plane vibrations in the SERRS spectrum and from theoretical calculations, it has been inferred that the interaction with the silver surface occurs via the nitrogen lone pair of the pyridyl or the dimethylamino group of the molecule with a tilted orientation. The observed red-shifts in the SERRS spectrum along various vibrations indicate strong interaction (chemisorption) of the HC dye with the silver surface. This is also supported by the presence of a Ag-N stretching vibration at 241 cm(-1). The effect of the dye concentration on the orientation of the molecule is also discussed.

Journal Article↗
PubMed2006

Psychological interventions for multiple sclerosis.

BACKGROUND: The unpredictable, variable nature of Multiple Sclerosis (MS), and the possibility of increasing disability, means that a diagnosis can have substantial psychological consequences. OBJECTIVES: To assess the effectiveness of psychological interventions for people with MS. SEARCH STRATEGY: We searched 19 databases up to December 2004; Cochrane MS Group Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PsychINFO, CINAHL and 14 others. We searched reference lists of articles, wrote to corresponding authors of the 13 papers identified by June 2004, and searched for trials in progress using 3 research registers. SELECTION CRITERIA: Randomised controlled trials of interventions described as wholly or mostly based on psychological theory and practice, in people with MS. Primary outcome measures were disease specific and general quality of life, psychiatric symptoms, psychological functioning, disability, and cognitive outcomes. Secondary outcome measures were number of relapses, pain, fatigue, health care utilisation, changes in medication, and adherence to other therapies. DATA COLLECTION AND ANALYSIS: Pertinent studies were identified from abstracts by one author. Full papers were independently compared to selection criteria by four authors. Key details were extracted from relevant papers using a standard format, and studies scored on three dimensions of quality. The review is organised into four mini-reviews (MR) dependent on the intervention's target population; people with cognitive impairments (MR1), people with moderate to severe disability (MR2), people with MS (no other criteria) (MR3), and people with depression (MR4). MAIN RESULTS: Overall 16 studies were identified and included. MR1: three trials (n=145). Some evidence of effectiveness of cognitive rehabilitation on cognitive outcomes, although this was difficult to interpret because of the large number of outcome measures used. MR2: three trials (n=80). One small trial suggesting psychotherapy may help with depression. MR3: seven studies (n=688). Some evidence that cognitive behavioural therapy may help people adjust to, and cope with, having MS (three trials). The other trials were diverse in nature and some difficult to interpret because of multiple outcome measures. MR4: three trials (n=93). Two small studies of cognitive behavioural therapy showed significant improvements in depression. AUTHORS' CONCLUSIONS: The diversity of psychological interventions identified indicates the many ways in which they can potentially help people with MS. No definite conclusions can be made from this review. However there is reasonable evidence that cognitive behavioural approaches are beneficial in the treatment of depression, and in helping people adjust to, and cope with, having MS.

Adaptation, Psychological↗
PubMed2006

XPS studies of chemically modified banana fibers.

Banana fibers obtained from the sheath of the banana plant (Musa Sapientum) whose major constituent is cellulose were modified using various chemical agents in order to improve their compatibility with the polymer matrix. The change in the surface composition of the raw and chemically modified fiber was investigated using various techniques such as solvatochromism, electrokinetic measurements, and XPS. Surface characterization by XPS showed the presence of numerous elements on the surface of the fiber. Investigation of the surface after alkali treatment on the other hand showed the removal of most of the elements. Silane treatment was found to introduce a considerable amount of silicon on the surface of the fiber. The [O]/[C] ratio was found to decrease in all cases except for the fluorinated and vinyl silane treated fibers. Detailed investigation of the deconvoluted C 1s spectra revealed the change in the percentage atomic concentration of the various elements on the fiber surface. The dissolution of the various surface components by alkali treatment, which was earlier revealed by SEM, was further confirmed by XPS. The XPS results were found to perfectly agree with the solvatochromic and electrokinetic measurements.

Acetic Anhydrides↗
PubMed2006

Evaluation of oestrogen and progesterone receptor status in HER-2 positive breast carcinomas and correlation with outcome.

AIM: HER-2/neu amplification occurs in 15-25% of breast carcinomas. This oncogene, also referred to as c-erbB-2, encodes a transmembrane tyrosine kinase receptor belonging to the epidermal growth factor receptor family. HER-2 over-expression is reported to be associated with a poor prognosis in breast carcinoma patients and in some studies is associated with a poorer response to anti-oestrogen therapy. These patients are less likely to benefit from CMF (cyclophosphamide, methotrexate, fluorouracil)-based chemotherapy compared with anthracycline-based chemotherapy. The aim of this study was to evaluate breast carcinomas to determine hormone receptor status and if there is a difference in breast cancer specific survival for HER-2 positive patients. METHODS: A total of 591 breast carcinomas were evaluated using immunohistochemistry (IHC) for oestrogen receptor (ERp), progesterone receptor (PRp) and three different HER-2 antibodies (CB11, A0485 and TAB250). Percentage of tumour cells and intensity of staining for ERp were evaluated using a semiquantitative method. RESULTS: Of the 591 tumours, 91 (15.4%) showed 3+ membrane staining for HER-2 with one or more antibodies. Of these 91 tumours, 41 (45.1%) were ERp+/PRp+, seven (7.7%) were ERp+/PR-, six (6.6%) were ERp-/PRp+ and 37 (40.7%) were ERp-/PR-. Of HER-2 positive tumours, 5.5% showed >80% 3+ staining for ERp compared with 31.8% of 0-2+ HER-2 tumours; 24.2% of HER-2-positive tumours showed 60% or more cells with 2+ or 3+ staining for ERp. Treatment data were available for 209 patients and no difference was observed in breast cancer specific survival (BCSS) with HER-2 status and tamoxifen. CONCLUSION: Oestrogen receptor status cannot be used to select tumours for evaluation of HER-2 status, and oestrogen and progesterone receptor positivity does not preclude a positive HER-2 status. There is a higher proportion of ERp negative tumours associated with HER-2 positivity, however, more than 20% of HER-2 positive tumours show moderate or strong staining for ERp. HER-2 positive patients in this study did not show an adverse BCSS with tamoxifen treatment unlike some previous studies.

Biomarkers, Tumor↗
PubMed2006

How should we diagnose suspected deep-vein thrombosis?

BACKGROUND: Many different approaches are used to diagnose suspected deep-vein thrombosis (DVT), but there has been little formal comparison of strategies. AIM: To identify the most cost-effective strategy for the UK National Health Service (NHS). DESIGN: Systematic review, meta-analysis and cost-effectiveness analysis. METHODS: We identified 18 strategies and estimated the diagnostic performance of constituent tests by systematic review and meta-analysis. Outcomes of testing and treatment were estimated from published data or by an expert panel. Costs were estimated from NHS reference costs and published data. We built a decision-analysis model to estimate, for each strategy, the overall accuracy, costs, and outcomes (valued as quality-adjusted life-years, QALYs), compared to a 'no testing, no treatment' alternative. Probabilistic analysis estimated the net benefit of each strategy at varying thresholds for willingness to pay for health gain. RESULTS: At the thresholds for willingness to pay recommended by the National Institute for Clinical Excellence (20,000 pounds sterling-30,000 pounds sterling per QALY), the optimal strategy was to discharge patients with a low or intermediate Wells score and negative D-dimer, limiting ultrasound to those with a high score or positive D-dimer. Strategies using radiological testing for all patients were only cost-effective at 40,000 pound sterling per QALY or more. DISCUSSION: The optimal strategy for DVT diagnosis is to use ultrasound selectively in patients with a high clinical risk or positive D-dimer. Radiological testing for all patients does not appear to be a cost-effective use of health service resources.

Cost-Benefit Analysis↗
PubMed2006

Impetigo: incidence and treatment in Dutch general practice in 1987 and 2001--results from two national surveys.

BACKGROUND: Impetigo is a common skin infection in children. The epidemiology is relatively unknown, and the choice of treatment is subject to debate. OBJECTIVE: The objective of our study was to determine the incidence and treatment of impetigo in Dutch general practice, and to assess trends between 1987 and 2001. METHODS: We used data from the first (1987) and second (2001) Dutch national surveys of general practice. All diagnoses, prescriptions and referrals were registered by the participating general practitioners (GPs), 161 and 195, respectively. RESULTS: The incidence rate of impetigo increased from 16.5 (1987) to 20.6 (2001) per 1000 person years under 18 years old (P < 0.01). In both years, the incidence was significantly higher in summer, in rural areas and in the southern region of the Netherlands, compared with winter, urban areas and northern region, respectively. Socioeconomic status was not associated with the incidence rate. From 1987 to 2001, there was a trend towards treatment with a topical antibiotic (from 43% to 64%), especially fusidic acid cream and mupirocin cream. Treatment with oral antibiotics (from 31% to 14%) and antiseptics (from 11% to 3%) was prescribed less often. CONCLUSIONS: We have shown an increased incidence of impetigo in the past decade, which may be the result of an increased tendency to seek help, or increased antibiotic resistance and virulence of Staphylococcus aureus. Further microbiological research on the marked regional difference in incidence may contribute to understanding the factors that determine the spread of impetigo. Trends in prescribing for impetigo generally follow evidence-based knowledge on the effectiveness of different therapies, rather than the national practice guideline.

Adolescent↗