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J Baines

Publications and source records attributed to J Baines.

10 recordsLinked to original sources
PubMed2000

Point of view: energy factors for food labelling and other purposes should be derived in a consistent fashion for all food components.

In Australia, the process by which food energy factors are derived for food labelling purposes is under review. One of the questions of international relevance is whether energy factors should be derived using a definition of metabolisable energy (ME) or a definition of net (metabolisable) energy (NME), or some mixture of the two. ME describes the food energy available for heat production and body gains. NME deducts obligatory thermogenesis from ME in an attempt to reflect the food energy that can be converted to ATP energy within the body. Some countries use NME to derive energy factors for novel food ingredients such as sugar alcohols and polydextrose, but continue to use ME for protein, fat, carbohydrate, and alcohol. The present paper puts a case for using a consistent system (ME at the present time) for all food components. Reasons for this include: consistent application to all food components allows valid comparisons between products; food energy values and estimates of energy expenditure (food energy requirements) should be directly comparable; NME does not account for all sources of thermogenesis; differences between ME and NME for sugar alcohols and polydextrose are small in the context of the whole diet; and the ME system does not preclude information about metabolic efficiency being provided as additional information. Any major change to the way in which energy values are expressed (e.g. global adoption of the NME system) merits wide discussion among the human nutrition community. One aim of this present paper is to stimulate this discussion.

Energy Intake↗
PubMed2000

Radiological changes five years after unicompartmental knee replacement.

Failure of a unicompartmental knee replacement (UKR) may be caused by progressive osteoarthritis of the knee and/or failure of the prosthesis. Limb alignment can influence both of these factors. We have examined the fate of the other compartments and measured changes in leg alignment after UKR. A total of 50 UKRs was carried out on 45 carefully selected patients between 1989 and 1992. At operation, deliberate attempts were made to avoid overcorrection of the deformity. Four patients died, one patient was lost to follow-up and two knees were revised before review which was at a minimum of five years. Standard long-leg weight-bearing anteroposterior views of the knee and skyline views of the patellofemoral joint were taken before and at eight months and five years after operation. The radiographs of the remaining 43 knees were reviewed twice by blind and randomised assessment to measure the progression of osteoarthritis within the joints. Overcorrection of the deformity in the coronal plane was avoided in all but two knees. Only one showed evidence of progression of osteoarthritis within the patellofemoral joint, and this was only identified in one of the four assessments. Deterioration in the state of the opposite tibiofemoral compartment was not seen. Varus deformity tended to recur. Recurrent varus of 2 degrees was observed between eight months and five years after operation. There was no correlation between the postoperative tibiofemoral angle and the extent of recurrent varus recorded at five years. Changes in alignment may be indicative of minor polyethylene wear or of subsidence of the tibial component. The incidence of progressive osteoarthritis within the knee was very low after UKR. Patients should be carefully selected and overcorrection of the deformity be avoided.

Aged↗
PubMed1998

Evaluating the donor pool: impact of using hearts from donors over the age of 49 years.

The shortage of hearts for transplantation has led to the use of organs from older donors in many centres. Despite the lack of coronary angiography on potential organ donors, hearts from carefully selected donors over 49 years of age have been used at this centre since 1988. In the study reported here looked at the impact of this strategy on morbidity and mortality. Between May 1988 and August 1996, 400 first heart transplants were performed, 35 recipients (31 male, 4 female; age 51 +/- 5.9 years) received hearts from donors over 49 years of age (group 1) while 365 (310 male, 55 female; age 49 +/- 9.7 years) had younger donors (group 2). The mean ischaemic time was 189 min (+/- 63.1) in group 1 and 180 min (+/- 59.2) in group 2 (n.s.). The main aetiology of heart failure in groups 1 and 2 was coronary artery disease in 46% and 51%, and dilated cardiomyopathy in 40% and 45% respectively (n.s.). There were no differences in the duration of stay on the intensive care unit or in hospital between the groups. One-year survival was 79% in group 1 and 82% in group 2 (n.s.) and actuarial 5-year survival 69% and 67%, respectively. Six patients in group 1 (17%) and 45 patients in group 2 (12%) died in the first 3 months; of these primary donor organ failure accounted for 50% in group 1 and 13.3% in group 2 (n.s.). Episodes of acute rejection (in the first 3 months) were similar in the two groups: 1.4 and 1.6 per 100 patient days, respectively. Infection rates were also similar: 0.5 and 0.6 per 100 patient days, respectively. The prevalence of coronary artery disease on surveillance coronary angiography at 2 years was 23% in group 1 and 9% in group 2 (P < 0.005). There was a greater proportion of CMV antibody donors in the older donor group, but the association between donor age and coronary artery disease persisted after adjusting for CMV status in multivariate analysis. Too few patients underwent angiography thereafter for valid comparisons. In summary, recipients of organs from donors aged 49 years and over can expect comparable survival rates and morbidity levels to recipients of organs from younger donors, at least in the first 2 years postoperation. There is evidence that older donors confer a significantly higher risk of cardiac allograft vasculopathy which may result in a greater attrition rate thereafter. Careful follow-up of these patients after 2 years is required.

Age Factors↗
PubMed1996

Energy expenditure in free-living smokers and nonsmokers: comparison between factorial, intake-balance, and doubly labeled water measures.

Free-living energy expenditure (EE) was measured in 11 smokers (6 females, 5 males) and 10 nonsmokers (6 females, 4 males) by using three methods. Factorial measures (FEE) used measured basal metabolic rate (BMR), records of time spent in six activity categories over 28 d, and average published energy costs of activities. Intake-balance measures (IBEE) used recorded dietary energy intake and changes in energy stores over 28 d. Doubly labeled water measures (DLWEE) used a two-point method over 8-12 d. Level of activity (1.54 +/- 0.07 and 1.55 +/- 0.06 x BMR) and FEE (9573 +/- 1501 and 9540 +/- 1663 kJ/d) were not different between smokers and nonsmokers, respectively. DLWEE was higher than FEE in both smokers (25.9 +/- 13.5%, P < 0.001) and nonsmokers (10.4 +/- 13.8%, P < 0.05), suggesting factorial underestimation in both groups, although the difference between DLWEE and FEE was significantly greater in smokers than in nonsmokers (P < 0.02). IBEE was higher than FEE in smokers (7.5 +/- 10.1%, P < 0.05) but not different from FEE in nonsmokers (2.7 +/- 16.6%), suggesting factorial underestimation in smokers only. DLWEE was higher than IBEE in smokers (13.8 +/- 12.6%, P < 0.01) but not significantly different from IBEE in nonsmokers (6.2 +/- 16.0%). The discrepancies between DLWEE and IBEE in smokers and DLWEE and FEE in nonsmokers preclude conclusion about absolute levels of daily EE. However, both DLWEE-FEE and IBEE-FEE comparisons suggest that our factorial method underestimates free-living EE in smokers relative to nonsmokers, although the effect is larger with the DLWEE-FEE than with the IBEE-FEE comparison.

Adult↗
PubMed1996

Role of the accident and emergency department in the non-heart-beating donor programme in Leicester.

OBJECTIVE: To describe the development of a non-heart-beating donor (NHBD) programme in an accident and emergency (A&E) department over a three year period. BACKGROUND AND METHODS: The A&E department at the Leicester Royal Infirmary at present deals with approximately 200 prehospital cardiopulmonary arrests per year. A programme of kidney retrieval from non-heart-beating donors was started in April 1992. Strict criteria for admission to the programme, appropriate consent procedures, facilities, lines of communication, and feedback were developed to enhance its success. RESULTS: Of 66 patients referred to the NHBD programme over a three year period from 1 April 1992, 51 sets of relatives were available to be asked for possible organ donation, and 34 sets (66%) gave their consent. Twenty five patients had successful in situ perfusion of the kidneys. Forty seven organs were retrieved and 34 went on to be transplanted. To date, 27 kidneys are still working. As a result, 23.8% of kidneys transplanted in Leicester over this time period have been from the NHBD programme. CONCLUSIONS: The NHBD programme in Leicester has proved very successful, requiring organisation of resources and personnel both from the transplant service and the A&E department. The programme has provided such a significant boost to the renal transplant rate in Leicester that other hospitals with large A&E departments should consider setting up similar programmes.

Emergency Service, Hospital↗
PubMed1992

A comparison of transcutaneous end-tidal and arterial measurements of carbon dioxide during general anaesthesia.

A randomized, prospective study was performed to evaluate the accuracy of a new transcutaneous carbon dioxide (CO2) monitor (Fastrac) during general anaesthesia. Twenty-two adult patients undergoing elective surgery were subjected to three different levels of minute ventilation by varying their respiratory rates in a randomized cross-over design. Simultaneous measurements of transcutaneous CO2 (PTCCO2) and arterial CO2 (PaCO2) were obtained at three levels of minute ventilation (low, medium and high). End-tidal CO2 (PETCO2) values were also recorded from a mass spectrometer (SARA) at each time period. A total of 66 data sets with PaCO2 ranging from 28-62 mmHg were analyzed. The PTCCO2 values demonstrated a high degree of correlation with PaCO2 over the range of minute ventilation (y = 0.904x + 6.36, r = 0.92, P less than 0.001). The PETCO2 measurement also demonstrated a generally good correlation with PaCO2 (y = 0.62x + 9.21, r = 0.89, and P less than 0.01). However, the PETCO2-PaCO2 gradients (mean 7.0 +/- 3.1 mmHg) were greater than the PTCCO2-PaCO2 gradients (mean 2.3 +/- 2.4 mmHg) at all three levels of minute ventilation (P less than 0.05). These differences were greatest when PaCO2 was in the high range (48-60 mmHg). We conclude that the new Fastrac CO2 monitor is accurate for monitoring carbon dioxide levels during general anaesthesia. The new transcutaneous devices provide an effective method for non-invasive monitoring of CO2 in situations where continuous, precise control of CO2 levels is desired.

Adult↗
PubMed1991

The diversity and unity of Herpesviridae.

The family herpesviridae contains over 100 viruses endogenous to humans and to a wide variety of eukaryotic organisms. Inclusion in the family is based on architecture of the virion. The viruses differ significantly with respect to base composition and sequence arrangements of their DNAs, but share many biologic properties including the ability to remain latent in their hosts. On the basis of their biologic properties the herpesviruses have been classified into three subfamilies, i.e. alphaherpesvirinae, betaherpesvirinae and gammaherpesvirinae. The members of each subfamily share many properties including greater conservation and colinear arrangements of their genes. As a rule, more than one herpesvirus has been isolated from animals of economic importance and both humans have yielded viruses belong to all three subfamilies of the herpesviridae.

Animals↗