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Biomedical subjects

P Robinson

Publications and source records attributed to P Robinson.

At least 19 recordsLinked to original sources

Clinical effectiveness and dose response of image-guided intra-articular corticosteroid injection for hip osteoarthritis.

OBJECTIVES: To assess symptomatic change after intra-articular corticosteroid (IAST) injection at 2 doses in hip osteoarthritis (OA), and to examine dose response and predictors of response. METHODS: Patients with hip OA (90 women and 30 men and median age 64 yrs) referred for IAST fluoroscopic injection were included in this longitudinal, clinical trial. WOMAC scores, body mass index (BMI), conventional radiographic grade (Kellgren and Lawrence scoring) and ultrasound measures (including capsular thickness and osteophyte assessments) were recorded at baseline. In the first phase of the study, 75 patients were injected with 40 mg methylprednisolone; another 45 patients were injected with 80 mg in the second phase. Change in WOMAC scores from baseline to weeks 6 and 12 were calculated for each dose and then dose comparisons were made. Clinical responders (>15% reduction in baseline pain score) were identified in order to establish predictors of response. RESULTS: For the 40 mg dose, there was a statistically significant improvement in pain (P < 0.001) and stiffness (P < 0.001) but not disability at week 6, and only the improvement in stiffness at week 12 was maintained (P = 0.041). For the 80 mg dose, there was significant improvement in pain (P < 0.001), stiffness (P < 0.001) and disability (P < 0.001) at week 6, which was maintained for all domains at week 12 (P = 0.002; P = 0.001; P < 0.001). When the doses were compared, the 80 mg dose demonstrated a significant improvement compared with the 40 mg group for stiffness at week 12 (P = 0.026) and disability at both weeks 6 and 12 (P = 0.026; P = 0.004). Imaging findings did not relate to severity of symptoms or response to IAST. CONCLUSIONS: In these two hip OA cohorts, both the 40 mg and 80 mg IAST doses had a beneficial effect at week 6, while the 80 mg dose maintained this improvement at week 12. Comparison of the two dose groups provided some evidence of a dose response. Randomized controlled trials of IAST for hip OA are now required.

Adult↗

Trace element and Sigma DDT concentrations in horticultural soils from the Tasman, Waikato and Auckland regions of New Zealand.

The long-term routine use of agrichemicals can result in elevated levels of trace elements and persistent organic pollutants in soils. Trace element concentrations and SigmaDDT levels were measured in soil (0-7.5 cm) samples collected from horticultural and grazing properties in 3 regions of New Zealand (Auckland, Tasman and Waikato). Elevated levels of arsenic (<2 to 58 mg kg(-1)), cadmium (<0.1 to 1.5 mg kg(-1)), copper (5 to 523 mg kg(-1)), lead (5 to 243 mg kg(-1)) and SigmaDDT (<0.03 to 34.5 mg kg(-1)) were detected in soils from all 3 regions. With the exception of cadmium and zinc, significantly higher levels of contaminants were generally detected in horticultural soils than in grazing soils. Our results have implications for the on-going use of agrichemicals as concentrations of cadmium, copper, tin and zinc in some samples exceeded ecotoxicity based soil criteria. The p,p'-DDE:DDT ratios indicate that the degradation of DDT in NZ horticultural soils may be inhibited by the co-contamination with trace elements.

Agriculture↗

Effects of unilateral laser-assisted ventriculocordectomy in horses with laryngeal hemiplegia.

REASONS FOR PERFORMING STUDY: Recent studies have evaluated surgical techniques aimed at reducing noise and improving airway function in horses with recurrent laryngeal neuropathy (RLN). These techniques require general anaesthesia and are invasive. A minimally invasive transnasal surgical technique for treatment of RLN that may be employed in the standing, sedated horse would be advantageous. OBJECTIVE: To determine whether unilateral laser-assisted ventriculocordectomy (LVC) improves upper airway function and reduces noise during inhalation in exercising horses with laryngeal hemiplegia (LH). METHODS: Six Standardbred horses were used; respiratory sound and inspiratory transupper airway pressure (Pui) measured before and after induction of LH, and 60, 90 and 120 days after LVC. Inspiratory sound level (SL) and the sound intensities of formants 1, 2 and 3 (Fl, F2 and F3, respectively), were measured using computer-based sound analysis programmes. In addition, upper airway endoscopy was performed at each time interval, at rest and during treadmill exercise. RESULTS: In LH-affected horses, Pui, SL and the sound intensity of F2 and F3 were increased significantly from baseline values. At 60 days after LVC, Pui and SL had returned to baseline, and F2 and F3 values had improved partially compared to LH values. At 90 and 120 days, however, SL increased again to LH levels. CONCLUSIONS: LVC decreases LH-associated airway obstruction by 60 days after surgery, and reduces inspiratory noise but not as effectively as bilateral ventriculocordectomy. POTENTIAL RELEVANCE: LVC may be recommended as a treatment of LH, where reduction of upper airway obstruction and respiratory noise is desired and the owner wishes to avoid risks associated with a laryngotomy incision or general anaesthesia.

Animals↗

Lay and expert perceptions of zoonotic risks: understanding conflicting perspectives in the light of moral theory.

As in many other areas, there is a divide between lay and expert perceptions of risk within the food sector, and this can lead to disagreement over priorities in food risk management. The risk perception literature tends to stress that the parties involved in this disagreement have different concepts of risk and hence are bound more or less to talk at cross-purposes. This paper suggests an alternative analysis: In the light of moral theory, the conflicting perspectives can be understood as a genuine moral conflict. When this conflict is conceptualised, a rational dialogue becomes possible. The paper reports a series of qualitative interviews with lay people and experts on zoonotic food risks. The interviews are used to reconstruct the values underlying some of the dominant perspectives. The conflict between these stylised perspectives is then analysed with the help of moral theory. Finally, some consequences for risk communication are made clear.

Creutzfeldt-Jakob Syndrome↗

Association of body composition and lung function in children with cystic fibrosis.

Survival in cystic fibrosis has improved significantly in the last 30 years, with major therapeutic goals of delaying the progressive loss of pulmonary function and maintaining normal growth. Dual-energy X-ray absorptiometry (DEXA) was performed in children with cystic fibrosis (CF) to assess both bone mineral density and body composition. We hypothesised that there would be an association between body composition and pulmonary function in children with CF. Fifty subjects with CF (28 males), mean age 12.7 years, participated in the study. Body composition was determined by DEXA. Body mass index (BMI) was calculated from the ratio of weight/height2 (kg/m2). Lung function was assessed by spirometry. Most patients (78%) had mild lung disease. The mean forced expired volume in 1 sec percent predicted (FEV1% predicted) for the 50 patients was 79.2% (range, 24-117%). There was a strong association between FEV1% predicted and BMI (R=0.59, P=0.0001). Fat-free mass had positive association with pulmonary function tests (R=0.30, P=0.03). Although fat mass showed a positive correlation with pulmonary function, this association did not reach statistical significance. In our group of children with CF and mild lung disease, pulmonary function was more strongly associated with BMI than with fat and fat-free mass.

Absorptiometry, Photon↗

Respiratory and gastrointestinal complications of caustic ingestion in children.

OBJECTIVES: To determine circumstances surrounding the ingestion of caustic substances, the incidence of respiratory and gastrointestinal symptoms at presentation, and the degree of investigation and active treatment during hospitalisation. Long term respiratory and gastrointestinal sequelae were also studied. DESIGN: Retrospective case note study covering a 10 year period. SETTING: Tertiary children's hospital. PATIENTS: Children and adolescents presenting following caustic ingestions to the Royal Children's Hospital, Melbourne. MAIN OUTCOME MEASURES: Requirement for interventional oesophagoscopy/bronchoscopy, respiratory support or admission to intensive care, and long term gastrointestinal or respiratory sequelae noted. RESULTS: Thirty two cases of caustic ingestion were identified in 31 patients (median age 2.6 years; 78% boys). The average time in hospital was 2 days. Two patients (6%) required intensive care nursing, and both required intubation with mechanical ventilation (average 33 hours). Thirty patients (97%) underwent diagnostic oesophagoscopy, and two underwent laryngoscopy or bronchoscopy for visualisation of the upper airway. No patient had long term respiratory consequences. Two patients (6%) sustained significant oesophageal injuries requiring interventional oesophagoscopy. CONCLUSIONS: Caustic ingestion is overrepresented in boys. Most ingestions involve household cleaning products. Symptoms on admission do not usually require intensive care admission. Gastrointestinal symptoms predominate at presentation, however, these are usually mild. Respiratory symptoms are uncommon and respiratory involvement requiring intervention is rare, although the presence of respiratory symptoms should be viewed as potentially serious. Long term sequelae of caustic ingestion are rare and in this series only affected the gastrointestinal tract. The indications for diagnostic endoscopy need further evaluation.

Adolescent↗

Adductor-related groin pain in athletes: correlation of MR imaging with clinical findings.

OBJECTIVE: To evaluate gadolinium-enhanced MR imaging in athletes with chronic groin pain and correlate with the clinical features. DESIGN AND PATIENTS: MR examinations performed in 52 athletes (51 male, 1 female; median age 26 years) with chronic groin pain and 6 asymptomatic control athletes (6 male; median age 29 years) were independently reviewed by two radiologists masked to the clinical details. Symptom duration (median 6 months) and clinical side of severity were recorded. Anatomical areas in the pelvis were scored for abnormality (as normal, mildly abnormal or abnormal) and an overall assessment for side distribution of abnormality was recorded, initially without post-gadolinium sequences and then, 3 weeks later (median 29 days), the post-gadolinium sequences only. Correlation between radiological and clinical abnormality was calculated by Spearman's correlation. RESULTS: Abnormal anterior pubis and enthesis enhancement significantly correlated with clinical side for both radiologists (both P=0.008). Abnormal anterior pubis and adductor longus enthesis oedema was significant for one radiologist ( P=0.009). All other features showed no significant correlation ( P>0.05). In the control cases there was no soft tissue abnormality but symphyseal irregularity was present ( n=2). For both radiologists assessment of imaging side severity significantly correlated with clinical side for post-gadolinium ( P=0.048 and P=0.023) but not non-gadolinium sequences ( P>0.05). CONCLUSION: The extent and side of anterior pubis and adductor longus enthesis abnormality on MR imaging significantly and reproducibly correlates with the athletes' current symptoms in chronic adductor-related groin pain.

Adolescent↗

Comparison of first-line antiretroviral therapy with regimens including nevirapine, efavirenz, or both drugs, plus stavudine and lamivudine: a randomised open-label trial, the 2NN Study.

BACKGROUND: The 2NN Study was a randomised comparison of the non-nucleoside reverse-transcriptase inhibitors (NNRTI) nevirapine and efavirenz. METHODS: In this multicentre, open-label, randomised trial, 1216 antiretroviral-therapy-naive patients were assigned nevirapine 400 mg once daily, nevirapine 200 mg twice daily, efavirenz 600 mg once daily, or nevirapine (400 mg) and efavirenz (800 mg) once daily, plus stavudine and lamivudine, for 48 weeks. The primary endpoint was the proportion of patients with treatment failure (less than 1 log(10) decline in plasma HIV-1 RNA in the first 12 weeks or two consecutive measurements of more than 50 copies per mL from week 24 onwards, disease progression [new Centers for Disease Control and Prevention grade C event or death], or change of allocated treatment). Analyses were by intention to treat. FINDINGS: Treatment failure occurred in 96 (43.6%) of 220 patients assigned nevirapine once daily, 169 (43.7%) of 387 assigned nevirapine twice daily, 151 (37.8%) of 400 assigned efavirenz, and 111 (53.1%) of 209 assigned nevirapine plus efavirenz. The difference between nevirapine twice daily and efavirenz was 5.9% (95% CI -0.9 to 12.8). There were no significant differences among the study groups in the proportions with plasma HIV-1 RNA concentrations below 50 copies per mL at week 48 (p=0.193) or the increases in CD4-positive cells (p=0.800). Nevirapine plus efavirenz was associated with the highest frequency of clinical adverse events, and nevirapine once daily with significantly more hepatobiliary laboratory toxicities than efavirenz. Of 25 observed deaths, two were attributed to nevirapine. INTERPRETATION: Antiretroviral therapy with nevirapine or efavirenz showed similar efficacy, so triple-drug regimens with either NNRTI are valid for first-line treatment. There are, however, differences in safety profiles. Combination of nevirapine and efavirenz did not improve efficacy but caused more adverse events.

Adult↗

Experimental and computational studies of the desensitization process in the bovine rhodopsin-arrestin complex.

The deactivation of the bovine G-protein-coupled receptor, rhodopsin, is a two-step process consisting of the phosphorylation of specific serine and threonine residues in the cytoplasmic tail of rhodopsin by rhodopsin kinase. Subsequent binding of the regulatory protein arrestin follows this phosphorylation. Previous results find that at least three phosphorylatable sites on the rhodopsin tail (T340) and at least two of the S338, S334, or S343 sites are needed for complete arrestin-mediated deactivation. Thus, to elucidate the details of the interaction between rhodopsin with arrestin, we have employed both a computational and an in vitro experimental approach. In this work, we first simulated the interaction of the carboxy tail of rhodopsin with arrestin using a Monte Carlo simulated annealing method. Since at this time phosphorylation of specific serines and threonines is not possible in our simulations, we substitute either aspartic or glutamic acid residues for the negatively charged phosphorylated residues required for binding. A total of 17 simulations were performed and analysis of this shows specific charge-charge interactions of the carboxy tail of rhodopsin with arrestin. We then confirmed these computational results with assays of comparable constructed rhodopsin mutations using our in vitro assay. This dual computational/experimental approach indicates that sites S334, S338, and T340 in rhodopsin and K14 and K15 on arrestin are indeed important in the interaction of rhodopsin with arrestin, with a possible weaker S343 (rhodopsin)/K15 (arrestin) interaction.

Animals↗

A new, low-volume protein substitute for teenagers and adults with phenylketonuria.

Some older patients with phenylketonuria (PKU) fail to consume their protein substitute (with or without vitamin and mineral supplements) in prescribed amounts, which contributes to poor blood phenylalanine control. PKU Express (Vitaflo), is a new low-volume (amino acids 72 g/100 g), low-carbohydrate, phenylalanine-free protein substitute with added vitamins and minerals designed for people with PKU over 8 years of age. In an open intervention study, the aim was to investigate its acceptability and effectiveness in a group of teenagers and adults with PKU. Twenty-three subjects (15 female; 8 male) with PKU, who had a median age of 17 years (range 8-37 years) took the substitute for 8 weeks. A 3-day prospective diet diary, height, weight, plasma amino acids, biochemical and haematological nutritional analytes were measured at weeks 0 and 8. Skin-puncture bloods for plasma phenylalanine were collected every 2 weeks. The median weight of protein substitute (with or without vitamin and mineral supplements) consumed decreased by 33% from 150 g (range 140-180) daily to 100 g (range 100-125) daily ( p <0.001). Median change in energy intake decreased by a median of 10% (95% CI 2.0 to 18.0) when compared to intake on original protein substitute. On PKU Express, the intakes of all nutrients exceeded the dietary reference values but none was excessively high. Blood phenylalanine decreased by a mean of 37 micromol/L (95% CI-27 to 102) during the trial. Body mass index decreased in 40% of subjects. Changes in blood phenylalanine or body mass index were not statistically significant. Most of the nutritional, haematological and biochemical indices stayed within normal reference ranges for the analytes studied. Sixteen (70%) of the subjects had low plasma selenium at the start, but only 13 (57%) at the study end. Plasma vitamin B12 was high in 8 subjects at the start of the study and 9 at the end. Twenty-one subjects (96%) stated that the product was convenient and easy to prepare. However, 7 (32%) described the smell and 9 (46%) the texture as the same as or worse than those of previous protein substitutes. Because of the use of the premeasured sachets, some subjects were able to prepare their own protein substitute for the first time. PKU Express is a safe, efficacious, protein substitute that significantly reduces the daily volume of prescribed protein substitute.

Adolescent↗

Therapeutic impact of percutaneous spinal biopsy in spinal infection.

OBJECTIVE: To investigate the therapeutic impact of percutaneous spinal biopsy in patients with suspected spinal infection. DESIGN AND PATIENTS: A review of the case notes and imaging features of 36 patients who underwent percutaneous spinal biopsy was performed. From this group 20 patients with a prebiopsy diagnosis of spinal osteomyelitis were identified. Management before biopsy was noted including the use of antimicrobial therapy. The results of the histology and microbiology were noted along with the subsequent diagnosis and management. RESULTS: Eight of the 20 patients (40%) had received antibiotics before the biopsy. An organism was isolated in 8/20 cases (40%). Of the eight patients on antibiotics, two grew an organism (25%), including one case of candida in a patient receiving flucloxacillin. Out of 12 patients not on antibiotics there were six cases where an organism was isolated (50%). The result of the biopsy led to a change in management in seven of the 20 patients (35%). CONCLUSIONS: Many clinicians are treating spinal osteomyelitis empirically with antibiotics before biopsy, but this reduces the chance of isolating an organism and determining antibiotic sensitivity. Despite this biopsy led to a change in management in 35% of cases.

Adolescent↗

Cystic fibrosis patients and families support cross-infection measures.

A clonal strain of Pseudomonas aeruginosa (PA) was isolated in 1999 at the Royal Children's Hospital, Melbourne, Australia, after five unrelated children with cystic fibrosis (CF) died from severe lung disease aged <5 yrs. Subsequently, more than half of the patients in the clinic with PA were found to harbour this strain, and segregation measures were instituted at the hospital to prevent further spread. The aim of this study was to assess CF parent and patient responses to the segregation measures to determine overall support. A questionnaire was sent out to the families of 291 CF children treated at the centre. A 65% response rate was obtained. The majority of parents (85%) and patients > or=12 yrs old (63%) were positive about the segregation measures instituted. A total of 11% of parents and 25% of patients were unsure, and 4% of parents and 12% of children gave negative responses. Those who were not happy listed reasons such as concerns about the emotional impact of not socialising with other CF children, inconclusive evidence about person-person spread of infection and feelings of alienation created in the clinic by the separation. In conclusion, the majority of responding cystic fibrosis patients and their families understand and are supportive of infection control measures instituted at the Royal Children's Hospital, Melbourne, Australia.

Adult↗

Optimization of storage conditions for diluted working solutions of porcine factor VIII and performance of the Bethesda assay for the determination of antiporcine FVIII inhibitor titres.

The use of porcine factor VIII (FVIII) (Hyate:C, Ipsen) has proven to be very successful in treating patients with FVIII inhibitors. The best way to predict the usefulness of porcine FVIII therapy, and/or to estimate the appropriate treatment dose in a given patient, is to measure the patient inhibitor titre against porcine FVIII with the Bethesda assay, using porcine FVIII as the source of FVIII in the assay. The goals of the present study were to (1) find the optimal storage temperature, diluent and concentration for a working solution of porcine FVIII to be used as the source of FVIII for the porcine Bethesda assay, (2) assess the reliability of the labelled FVIII units in the preparation of such working solutions of porcine FVIII and (3) compare the inhibitor titres determined by the Bethesda assay using both porcine and human standard reference curves for measuring residual FVIII. The results of the present study demonstrate that a ready-to-use working solution of 1 U mL(-1) of Hyate:C diluted in human FVIII deficient plasma, either containing or deficient in von Willebrand factor antigen, is stable for up to 12 months, at -20 degrees C. The preparation of the 1 U mL(-1) working solution could be reliably calculated based on the units indicated on the vial label. Finally, using the human standard curve yields similar results to using the porcine standard curve for measuring any titre of allo- or auto-antibody against FVIII in the Bethesda assay, using Hyate:C as the source of FVIII. These findings are of practical value when performing a porcine FVIII-based Bethesda assay.

Animals↗

Peak inspiratory flows in children with cystic fibrosis.

OBJECTIVE: To show that in children with moderately severe cystic fibrosis lung disease: (i). inspiratory flow may be reduced; and (ii). peak inspiratory flow may be predicted from height, expiratory flow analysis or body mass index. METHODS: All children attending the Royal Children's Hospital, Melbourne, between May and July, 2001 who had cystic fibrosis, were aged > 5 years, were able to perform spirometry reproducibly and who had a forced expiratory volume in 1 s < 60% predicted were prospectively enrolled. Height, weight, peak inspiratory flow, forced expiratory volume in 1 s and forced vital capacity were recorded. Linear regression analysis was performed. RESULTS: The age range was 9.4-19.9 years. Sixteen boys and 11 girls were studied. All children had a peak inspiratory flow > 0.5 L/s. There was a significant relationship between peak inspiratory flow and forced vital capacity (R2 = 0.50) especially in boys (R2 = 0.65). In boys, peak inspiratory flow was significantly related to forced expiratory volume in 1 s (R2 = 0.47). There was no relationship between peak inspiratory flow and predicted values of expiratory flow, age, height, weight or body mass index. Logistic regression was used to predict the probability that peak inspiratory flow was < 2.0 L/s for a given forced vital capacity. If the forced vital capacity is > 2.5 L, peak inspiratory flow is likely to be > 2.0 L/s. CONCLUSIONS: In children with significant cystic fibrosis lung disease, peak inspiratory flow is likely to be > 0.5 L/s, which is required to activate dry powder inhalers. If the forced vital capacity is < 2.5 L, the peak inspiratory flow may be < 2.0 L/s, and a metered dose inhaler and spacer should be considered. Further studies that investigate the relationship between expiratory flow and peak inspiratory flow against an internal resistance are needed.

Child↗

Anaesthesia for an adolescent with mitochondrial encephalomyopathy-lactic acidosis-stroke-like episodes syndrome.

Anaesthesia for patients with mitochondrial disorders occurs with regularity, either for a diagnostic or therapeutic procedure associated with the syndrome or for unassociated surgery. We report the case of a 17-year-old boy with mitochondrial encephalomyopathy-lactic acidosis-stroke-like episodes (MELAS) syndrome who underwent a laparotomy for fundoplication. The potential hazards of anaesthesia for this patient, and the steps taken to avoid them, are discussed.

Adolescent↗

Symptoms of colorectal liver metastases: correlation with CT findings.

AIM: To correlate CT appearances of colorectal liver metastases (LM) with pattern and severity of symptoms. MATERIALS AND METHODS: One hundred and twenty patients with treated primary colorectal carcinoma were prospectively assessed by questionnaire for recent symptoms when attending for CT examination. Thorax, abdomen and pelvic CT scans were prospectively assessed for LM and extrahepatic disease (EHD). The number of LM, percentage liver replaced by LM and distribution of LM were recorded. RESULTS: Patients' ages ranged from 35 to 89 years (median 60) and 74/120 (62%) were male. Four subgroups were compared: group 1 - LM only (n = 30); 2 - EHD only (n = 22); 3 - both LM and EHD (n = 28); 4 - neither LM/EHD (n = 40). Anorexia was significantly worse in gp2 vs gp4 (P = 0.016) and lower abdominal pain (LAP) was significantly worse in gp2 vs gpl (P = 0.019). General pain was the worse symptom in all groups but notstatistically greater in any group. Patients with more than 10 LM had significantly worse anorexia (P = 0.002). general pain (P < 0.001) and LAP (P = 0.001). There was a trend (P > 0.05) towards worse symptoms with either volume of diseased liver or subcapsular LM. CONCLUSION: With increasing liver tumour burden there was an increase in symptomatology but extrahepatic abdominal metastatic tumour produced more symptoms than LM alone. Symptoms, particularly pain, therefore are not good predictors of hepatic metastatic disease.

Abdominal Pain↗

Pseudomonas cross-infection from cystic fibrosis patients to non-cystic fibrosis patients: implications for inpatient care of respiratory patients.

A 14-year-old boy with bronchiectasis secondary to chronic aspiration developed multiresistant Pseudomonas aeruginosa lower respiratory disease following several inpatient periods where accommodation and physiotherapy services were shared with cystic fibrosis (CF) patients known to be infected with the genetically identical strain of P. aeruginosa. Cross-infection with P. aeruginosa between CF patients and non-CF patients has not previously been described, and this finding raises significant issues relevant to the treatment of patients with non-CF suppurative lung disease.

Adolescent↗