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J Pringle

Publications and source records attributed to J Pringle.

At least 19 recordsLinked to original sources
PubMed2006

Assessment of maximal aerobic power and critical power in a single 90-s isokinetic all-out cycling test.

The purpose of this study was to establish the validity of a 90-s all-out test for the estimation of maximal oxygen uptake (V.O (2max)) and submaximal aerobic ability as represented by critical power. We hypothesized that the fall in power output by the end of the 90-s all-out test (end power) would represent the exhaustion of anaerobic work capability, and as such, would correspond with the critical power. Sixteen active individuals (mean +/- SD: 30 +/- 6 years; 69.6 +/- 9.9 kg) carried out a series of tests: (i) an incremental ramp test to determine V.O (2max), (ii) three fixed-work rate trials to exhaustion to determine critical power, and (iii) two 90-s all-out tests to measure end power and peak V.O (2). End power (292 +/- 65 W) was related to (r=0.89) but was significantly higher (p<0.01) than critical power (264 +/- 50 W). The mean +/- 95 % limits of agreement (29 +/- 65 W) were too low to use these variables interchangeably. The peak V.O (2) in the 90-s trial was significantly lower than the V.O (2max) (3435 +/- 682 ml x min (-1) vs. 3929 +/- 784 ml x min (-1); p<0.01); mean +/- 95 % limits of agreement was equal to 495 +/- 440 mL x min (-1). The 90-s all-out test cannot, therefore, assess both V.O (2max) and critical power in adult performers. The duration of all-out exercise required to allow V.O (2) to attain its maximum is longer than 90 s.

Adult↗
PubMed2006

Mortality of Swedish horses with complete life insurance between 1997 and 2000: variations with sex, age, breed and diagnosis.

The aim of this study was to evaluate the potential usefulness of the database maintained by the Swedish insurance company Agria for providing mortality statistics on Swedish horses. Mortality statistics (incidence rates and survival) were calculated, both crudely and stratified by sex, age, breed, breed group and diagnosis, for the horses with complete life insurance, which covers most health problems. The total mortality was 415 (95 per cent confidence interval [CI] 399 to 432) deaths per 10,000 horse-years at risk, and the diagnostic mortality, including only deaths with an assigned diagnosis, was 370 (95 per cent CI 355 to 386) deaths per 10,000 horse-years at risk. The diagnostic mortality of geldings was 459 (95 per cent CI 431 to 487), of mares 345 (95 per cent CI 322 to 365) and of stallions 214 (95 per cent CI 182 to 247) deaths per 10,000 horse-years at risk. The mortality rates increased with age and differed widely between breeds. Survival analysis showed that the median age at death of the horses enrolled before they were one year of age was 18.8 years. The most common cause of death or euthanasia was joint problems, which were responsible for 140 (95 per cent CI 130 to 149) deaths per 10,000 horse-years at risk. The results of multivariable models developed by using Poisson regression generally agreed well with the crude results.

Age Distribution↗
PubMed2006

Osteofibrous dysplasia of the tibia. Is there a need for a radical surgical approach?

Osteofibrous dysplasia is an unusual developmental condition of childhood, which almost exclusively affects the tibia. It is thought to follow a slowly progressive course and to stabilise after skeletal maturity. The possible link with adamantinoma is controversial and some authors believe that they are part of one histological process. We retrospectively reviewed 16 patients who were diagnosed as having osteofibrous dysplasia initially or on the final histological examination. Their management was diverse, depending on the severity of symptoms and the extent of the lesion. Definitive (extraperiosteal) surgery was localised "shark-bite" excision for small lesions in five patients. Extensive lesions were treated by segmental excision and fibular autograft in six patients, external fixation and bone transport in four and proximal tibial replacement in one. One patient who had a fibular autograft required further excision and bone transport for recurrence. Six initially underwent curettage and all had recurrence. There were no recurrences after localised extraperiosteal excision or bone transport. There were three confirmed cases of adamantinoma. The relevant literature is reviewed. We recommend extraperiosteal excision in all cases of osteofibrous dysplasia, with segmental excision and reconstruction in more extensive lesions.

Adamantinoma↗
PubMed2006

Reproducibility of variables derived from a 90 s all-out effort isokinetic cycling test.

AIM: The aim of this study was to examine the reliability of the power output profile obtained from a 90 s all-out isokinetic cycling test. METHODS: Within a 10 day period, 16 participants (-x+/-s: age 30.1+/-6.4 years; body mass 69.2+/-10.6 kg) performed an incremental VO2 max ramp test and two 90 s all-out efforts on an isokinetic cycle ergometer. Peak power (PP), mean power (MP), end power (EP) and fatigue index (FI) were determined. RESULTS: There were no significant differences between tests for MP, EP and FI values (P > 0.05) but PP was higher on the second test (P = 0.003). Ratio limits of agreement suggested that a repeated measurement might be expected in 95% of cases to be between 0.92 to 1.21 times the initial PP measurement and 0.97 to 1.07 times the initial MP measurement. The 95% limits of agreement for EP and fatigue were -23 to +33 W (1.8+/-9.7% of the mean) and -6.5% to 8.8% (2+/-7.6% of the mean), respectively. CONCLUSIONS: The 90 s all-out test appears to be a reliable test for given aspects of the physiological profile, with the exception of PP.

Adult↗
PubMed2005

Specific causes of morbidity among Swedish horses insured for veterinary care between 1997 and 2000.

The principal aim of this study was to analyse the incidence of disease due to general and more specific causes among over 100,000 horses covered by complete insurance for veterinary care by a Swedish insurance company during 1997 to 2000. The database was used to calculate the rate of cause-specific morbidity in horses of different ages, sexes and breed groups kept in different regions with different human population densities. The joints were the most commonly affected part of the body, followed by unspecified/whole body, the skin and the digestive system. The most common specific diagnosis was fetlock arthritis, followed by lameness of undefined origin, other locomotor problems, traumatic injuries to the skin, arthritis in several joints, and colic. Geldings had the highest rate of at least one disease event in the joints, unspecified/whole body, skeletal or respiratory system, whereas in the other four major systems the difference between the sexes was marginal.

Age Distribution↗
PubMed2005

Morbidity of Swedish horses insured for veterinary care between 1997 and 2000: variations with age, sex, breed and location.

The aim of this study was to evaluate the potential usefulness of the database maintained by the Swedish insurance company Agria for providing disease statistics on Swedish horses. The demography of the horses insured for veterinary care during the period 1997 to 2000 was recorded and the incidence of morbidity, defined as horses that required veterinary care that cost more than the policy excess, was calculated. Yearly incidences were calculated for horses that required veterinary care at least once, first overall, and then for horses with complete insurance, by sex, age, breed group, breed, location and human population density. Poisson regression was applied to a multivariable model to produce estimates of relative risk adjusted for other factors in the model, such as age. The total number of horse-years at risk for those with complete insurance was over 72,000 each year. The annual incidence rate for horses that required veterinary care at least once varied from 1080 to 1190 events per 10,000 horse-years at risk; for geldings the averaged incidence rate was 1398 events, for mares it was 1042 events, and for stallions it was 780 events per 10,000 horse-years at risk. There were considerable variations in incidence rate between breeds.

Age Distribution↗
PubMed2005

Diffuse pigmented villonodular synovitis of the foot and ankle treated with surgery and radiotherapy.

We followed up seven patients with histologically confirmed diffuse pigmented villonodular synovitis in a prospective study between 1992 ans 2001. The mean age at diagnosis was 30.7 years. The patients underwent synovectomy, followed by radiotherapy with a total dose of 35 Gy in 20 fractions. In all cases, the excision was considered incomplete when examined histologically. At an average follow up of 24 (18-36) months, six patients reported better function and reduced levels of pain. One patient remained symptomatic but did not have a recurrence. We conclude that a combined approach to a primary pigmented villonodular synovitis of the foot and ankle may reduce the risk of recurrence without functional impairment.

Adult↗
PubMed2005

Doxorubicin and cisplatin chemotherapy in high-grade spindle cell sarcomas of the bone, other than osteosarcoma or malignant fibrous histiocytoma: a European Osteosarcoma Intergroup Study.

There are limited data that define the role of chemotherapy in the treatment of high-grade spindle cell sarcomas of bone, other than osteosarcoma or malignant fibrous histiocytoma (MFH-B). This prospective study evaluates the effect of doxorubicin and cisplatin on these tumours. Thirty-seven patients, age 65 years, with spindle cell sarcoma of bone, except osteosarcoma or MFH-B, were included. Chemotherapy consisted of doxorubicin and cisplatin every 3 weeks for six cycles. Resection was performed after three cycles. In 15 patients with metastases, response assessment showed three complete responses (CR), four stable disease (SD), five progression; three were not evaluable. Median time to progression was 30 months (95% Confidence Interval (CI), 8-51 months) for the operable non-metastatic patients; median survival 41 months (95% CI, 16-82 months). Median time to progression in the metastatic group was 10 months (95% CI, 0-18 months) and median survival was 14 months (95% CI, 4-45 months). This study suggests a limited role for doxorubicin and cisplatin in metastatic high-grade spindle cell sarcoma of bone, other than osteosarcoma or MFH-B cases.

Adolescent↗
PubMed2004

The use of chondrogide membrane in autologous chondrocyte implantation.

UNLABELLED: Autologous chondrocyte implantation is a new technique for the treatment of chondral defects in the knee. The exact procedure involved is continuously being developed with the ultimate aim of achieving hyaline cartilage regeneration. We present the outcome of our series of 31 patients, focussing on the use of the chondrogide membrane in the implantation process. Assessment is presented both in the form of arthroscopic appearance at approximately 1 year, and in the form of clinical outcome measures at 1 year and at 2 years after the second stage of the procedure. CONCLUSION: the use of chondrogide membrane in the fixation of cells during the implantation process is associated with satisfactory clinical outcome and does not appear to show evidence of hypertrophy at one-year arthroscopy, as compared to periosteum.

Adolescent↗
PubMed2003

Gene expression array profile of human osteosarcoma.

The aims of this pilot study were to determine whether needle and open biopsies from osteosarcoma (OS) provide sufficient quality of mRNA for cDNA array analyses to gain insights into the expression profile of OS. A total of 22 samples collected from OS were used for array analyses. A primary cell culture was also established from one of the OS biopsies. Total RNA was extracted and probes were generated for cDNA arrays. cDNA probes were made for all the 22 samples. Two of these samples were needle core bone biopsies. Statistical analysis confirmed the reliability of array data obtained in 16 of the 22 samples. Known genes involved in bone metabolism and osteosarcoma were identified as highly expressed, and the putative new marker Ezrin was also identified. Confirmatory immunohistochemical staining using the Ezrin antibody was performed in a selection of samples.

Adolescent↗
PubMed2003

Single center experience of a new intensive induction therapy for ewing's family of tumors: feasibility, toxicity, and stem cell mobilization properties.

PURPOSE: To examine the feasibility, tolerability, and toxicity of an intensified induction regimen (vincristine, ifosfamide, doxorubicin, and etoposide [VIDE]) in patients with newly diagnosed Ewing's family of tumors (EFT); to assess ability to maintain dose-intensity, and predictability of peripheral-blood stem cell mobilization. PATIENTS AND METHODS: Thirty patients were treated with vincristine 1.4 mg/m2 (maximum 2 mg) on day 1, doxorubicin 20 mg/m2, ifosfamide 3 g/m2 plus mesna and etoposide 150 mg/m2 on days 1 to 3. Cycles were given every 21 days for up to six cycles. RESULTS: One-hundred and seventy cycles of VIDE were given. The median treatment interval was 21 days (21 to 42) and nadir count: hemoglobin 8.3 (6.3 to 11.9), neutrophils 0.045 (0.0 to 2.1), and platelets 45 (3 to 343). There were 96 episodes of infection requiring hospitalization (56%). Growth factor support reduced infectious complications by 34%. Etoposide dose was reduced, or omitted, in 24% of cycles. Four patients did not complete six cycles due to unacceptable toxicity and one patient progressed on treatment. Twenty patients underwent peripheral-blood stem cell harvesting, 15 after cycle 3, and five after cycle 4. Median CD34+ yield was 4.6 x 106/kg per patient (1.8 to 14.5). Overall response to treatment, measured in 24 patients, was 88%. Seven of 11 patients undergoing surgery achieved greater than 90% necrosis of tumor (64%). CONCLUSION: VIDE is an effective induction regimen with substantial but acceptable toxicity that allows predictable mobilization of stem cells. Maintenance of dose-intensity is feasible in the majority of patients. Growth factors play a role in maintaining dose-intensity and reduce infectious complications.

Adolescent↗
PubMed2003

A prospective, randomised comparison of autologous chondrocyte implantation versus mosaicplasty for osteochondral defects in the knee.

Autologous chondrocyte implantation (ACI) and mosaicplasty are both claimed to be successful for the repair of defects of the articular cartilage of the knee but there has been no comparative study of the two methods. A total of 100 patients with a mean age of 31.3 years (16 to 49) and with a symptomatic lesion of the articular cartilage in the knee which was suitable for cartilage repair was randomised to undergo either ACI or mosaicplasty; 58 patients had ACI and 42 mosaicplasty. Most lesions were post-traumatic and the mean size of the defect was 4.66 cm2. The mean duration of symptoms was 7.2 years and the mean number of previous operations, excluding arthroscopy, was 1.5. The mean follow-up was 19 months (12 to 26). Functional assessment using the modified Cincinatti and Stanmore scores and objective clinical assessment showed that 88% had excellent or good results after ACI compared with 69% after mosaicplasty. Arthroscopy at one year demonstrated excellent or good repairs in 82% after ACI and in 34% after mosaicplasty. All five patellar mosaicplasties failed. Our prospective, randomised, clinical trial has shown significant superiority of ACI over mosaicplasty for the repair of articular defects in the knee. The results for ACI are comparable with those in other studies, but those for mosaicplasty suggest that its continued use is of dubious value.

Adolescent↗
PubMed2003

Histological evaluation of chondral defects after autologous chondrocyte implantation of the knee.

We have performed a prospective, single-surgeon study analysing the histological results of autologous chondrocyte implantation. Fourteen patients underwent autologous chondrocyte implantation of the knee and were evaluated at one year by clinical assessment and arthroscopy. Standard staining was used to examine the sections. In addition, in situ hybridisation was used to establish type-IIa and type-IIb collagen mRNA expression and immunolocalisation techniques demonstrated the positions of type-II and type-X collagen. Eight patients regenerated hyaline cartilage and also contained type-X collagen in the deepest layers and type-II collagen in the deep layers. Three demonstrated fibrocartilage and had type-I collagen in the deep layers. In situ hybridisation revealed that all 14 samples had the potential to express both type-IIa and type-IIb collagen. We have shown that one year after the initial implantation chondrocytes are capable of producing type-II collagen and that they continue to proliferate and mature.

Adolescent↗
PubMed2002

Reversible self-polymerizing high T(g) lyoprotectants.

One mode of action of protectants in the storage of biological materials is by promoting the formation of a vitrified state on cooling or drying. In the case of preservation by drying, the glassy material comprises a low water content mixture of protectant and organic material. The protectant must on drying form a glassy state of glass transition temperature (T(g)) above the desired storage temperature. However, in some applications it must also be easily transported through cell membranes and this restricts the choice to a relatively limited number of small molecules, which typically exhibit very low glass transition temperatures. In this work we describe a self-polymerizing protectant comprising an inorganic salt and a small hydroxy functional molecule such as glycerol. This forms co-ordinate polymer chains of high T(g) on drying but rapidly depolymerizes into the original components on rehydration. The polymerization process is general for polyhydroxy compounds including glucose and related compounds.

Calcium Chloride↗
PubMed2002

Does the histological subtype of high-grade central osteosarcoma influence the response to treatment with chemotherapy and does it affect overall survival? A study on 570 patients of two consecutive trials of the European Osteosarcoma Intergroup.

Large randomised trials are mandatory when one wants to examine the effects of different aspects (such as the treatment modality) of a pathological condition on the overall outcome. This is especially true when studying a disease in which there is a multifactorial influence on progression and outcome such as osteosarcoma. Data on 570 patients with biopsy-proven primary central osteosarcoma of an extremity included in two consecutive studies of the European Osteosarcoma Intergroup (EOI) were analysed in order to evaluate if the histological subtype of the biopsy specimen correlated with the subtype of osteosarcoma represented in the resected specimen, if there was a relationship between the histological subtype and overall survival and if there was a relationship between the histological subtype and histological response to chemotherapy. High-grade osteosarcoma, as defined by established criteria, was subtyped as either conventional, chondroblastic, teleangiectatic, small cell, fibroblastic, osteoclast rich, anaplastic and sclerotic/osteoblastic well differentiated. A panel of experienced pathologists with a special interest in bone pathology was appointed to review the histological diagnosis and to assess the tumour response to chemotherapy on the resected specimen of each patient entered into the trials. Subtyping on the biopsy specimen proved to be highly representative for the subtype of the whole tumour. In 102 patients for which subtyping was performed on the biopsy and the resected specimens, there were only two discrepancies. Of the 568 patients for whom subtype was available, 404 (71%) were of the conventional type, 54 (10%) were chondroblastic, 53 (9%) had fibroblastic tumours and the remainder consisted of rare subtypes. A good response to preoperative chemotherapy was defined as 90% or more necrosis. The proportion of patients responding well to chemotherapy differed significantly between subtypes (Chi-square test statistics=11.44, P=0.01 on 3 degrees of freedom (d.f.)). In comparison with the conventional subtype, there was a higher proportion of good responders in the fibroblastic group and a lower proportion of good responders in the chondroblastic group. Good responders had a significantly better survival than patients who responded poorly to the pre-operative chemotherapy (logrank statistic=25.20, P<0.01 on 1 df). Survival did not differ significantly according to subtype (logrank statistic=2.72, P=0.44 on 3 df), although there was a suggestion that patients with chondroblastic tumours experienced a better long-term survival. This large set of prospectively-collected data provides important information on the relationship between pathological subtype, histological response and survival. Histological response has a known prognostic effect on survival, and we have shown that the rates of response differ by subtype. There is some evidence from this study that the specific histological subtypes, i.e. the chondroblastic subtype, experience better survival. However, despite this large multi-institutional study, we have insufficient numbers of non-conventional tumours to examine this unambiguously for these subsets.

Adolescent↗
PubMed2002

A pilot study of short-course intensive multiagent chemotherapy in metastatic and axial skeletal osteosarcoma.

BACKGROUND: This pilot study was undertaken to assess the feasibility, toxicity and response to short-course multiagent chemotherapy followed by high-dose chemotherapy (HDC) in patients with poor prognosis osteosarcoma. PATIENTS AND METHODS: A total of 30 patients entered the study. Chemotherapy consisted of four blocks of multiagent chemotherapy administered sequentially over a short period in a dose-intensive manner. This therapy was followed by HDC which consisted of carboplatin at an AUC8 x 3 days, etoposide 400 mg/m(2) x 3 days and cyclophosphamide 60 mg/kg x 2 days. RESULTS: A total of 227 cycles of chemotherapy were administered. The main toxicity (for blocks 1-4) was haematological. There were two treatment-related deaths: one post HDC due to sepsis and one during surgery. High-dose chemotherapy was administered to 11 patients (10 with extremity tumours and only one with a pelvic tumour). Twenty-seven patients underwent surgery to the primary. Histological response was assessed in 23 patients. Seven patients (30%) had >90% necrosis. Eight patients underwent pulmonary metastatectomy. The median survival time for the whole group was 16 months. The 2- and 3-year survival rates were 50% and 21% for those with extremity tumours and 19% and 13% for those with axial skeletal tumours. CONCLUSIONS: Dose-intensive multiagent chemotherapy though feasible in the group of patients with extremity tumours did not significantly improve the treatment outcome compared with conventional relapse therapy. Inferior survival rates in the axial skeletal group are attributed to less intensive treatment and poor local tumour control.

Adolescent↗
PubMed2002

Does birth weight predict adult serum cortisol concentrations? Twenty-four-hour profiles in the United kingdom 1920-1930 Hertfordshire Birth Cohort.

Low birth weight and weight in infancy are associated with adult insulin resistance and type 2 diabetes. A proposed mechanism is programming of the hypothalamic-pituitary-adrenal axis by intrauterine undernutrition, leading to persistently elevated cortisol concentrations. We examined 24-h serum cortisol profiles (samples every 20 min) in 83 healthy elderly men and women whose birth weight and infant weight were recorded. Variables derived from these profiles included trough, peak, and area under the curve concentrations; the time of onset, rate of rise, duration, and peak of the early morning cortisol rise; postprandial secretion; and regularity of secretion (approximate entropy). None of these parameters was related to birth weight, weight at 1 yr, or change in weight SD score between birth and 1 yr. Consistent with other studies, 0730-0900 h cortisol concentrations were higher in men and women of lower birth weight, although this was not statistically significant (P = 0.08). Our findings do not support the hypothesis that reduced intrauterine and infant growth are associated with continuously raised cortisol concentrations in old age. Programmed effects on the hypothalamic-pituitary-adrenal axis may influence reactivity rather than resting secretion.

Aged↗