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Biomedical subjects

J Beard

Publications and source records attributed to J Beard.

At least 19 recordsLinked to original sources
PubMed2001

Variations in dietary iron alter behavior in developing rats.

Iron deficiency in children is associated with retardation in growth and cognitive development, and the effects on cognition may be irreversible, even with treatment. Excessive iron has also been associated with neurological disease, especially in reference to the increased iron content in the brains of Alzheimer's disease and Parkinson's disease patients. This study evaluated the effects of dietary iron deficiency and excess iron on physical activity in rats. The animal model used is developmentally sensitive and permits control of the timing as well as the duration of the nutritional insult. Hence, to study the effects of early, late and long-term iron deficiency or excess iron (supplementation), rats were either made iron deficient or supplemented on postnatal day (PND) 10-21, PND 21-35 and PND 10-35. Some iron-deficient rats were iron repleted between PND 21-35. Different measures of motor activity were taken at PND 14, 17, 20, 27 and 34. Iron-deficient and iron-supplemented rats showed decreased activity and stereotypic behavior; this was apparent for any onset and duration of the nutritional insult. Recovery from iron deficiency did not normalize these functional variables, showing that the deleterious effects of early iron deficiency persist despite subsequent adequate treatment. This study demonstrates that iron deficiency in early life leads to irreversible behavioral changes. The biological bases for these behavioral alterations are not readily apparent, because iron therapy rapidly reverses the iron losses in all brain regions.

Age Factors↗
PubMed2000

Late summer and fall (March-May) pollen allergy and respiratory disease in Northern New South Wales, Australia.

BACKGROUND: Many people in the subtropical Northern Rivers area of New South Wales, Australia, blame the pollen of Tibouchina tree, which flowers at the same time as ragweed, Bahia grass and Bermuda grass, for hayfever and asthma exacerbations during fall between March and May. OBJECTIVES: To determine whether Tibouchina pollen is allergenic. To determine whether airborne ragweed pollen is present in this region for sufficient length of time and concentration to cause fall respiratory symptoms, and to determine if Bahia grass and Bermuda grass are associated with fall respiratory symptoms. METHODS: Pollen and Alternaria spores were monitored using a Burkard 7-day spore trap. Two hundred and six volunteers in the Northern Rivers area filled in questionnaires before skin prick tests (SPT) were performed with a panel of skin testing extracts. RESULTS: One hundred fifty-three (74.3%) subjects were atopic and reacted to one or more aeroallergens. Seventy were SPT positive to ragweed, OR 3.36 (CI 1.03 to 12.15) and 11 to Tibouchina (OR incalculable). Fifty of the 70 ragweed-positive subjects had fall hayfever or exacerbations of hayfever and/or asthma, OR 23.4 (CI 8.90 to 64.00). Eleven subjects were SPT positive to Tibouchina extract. There was a statistical association between Bermuda grass and hayfever, but not asthma OR 13.44 (CI 1.85 to 27.04). CONCLUSIONS: Ragweed pollen was present for a sufficient length of time and concentration to sensitize and provoke fall hayfever and asthma exacerbations. Tibouchina pollen is an aeroallergen causing mild-to-moderate allergic symptoms in a few people. There is an association between Bahia grass and asthma in children, and between Bermuda grass and allergic rhinitis in adults.

Adolescent↗
PubMed2000

Iron status and exercise.

The prevalence of iron deficiency anemia is likely to be higher in athletic populations and groups, especially in younger female athletes, than in healthy sedentary individuals. In anemic individuals, iron deficiency often not only decreases athletic performance but also impairs immune function and leads to other physiologic dysfunction. Although it is likely that dietary choices explain much of a negative iron balance, evidence also exists for increased rates of red cell iron and whole-body iron turnover. Other explanations of decreased absorption and increased sweat or urine losses are unlikely. The young female athlete may want to consider use of low-dose iron supplements under medical and dietary supervision to prevent a decline in iron status during training.

Adolescent↗
PubMed1999

The endovascular management of blue finger syndrome.

OBJECTIVES: To review our experience of the endovascular management of upper limb embolisation secondary to an ipsilateral proximal arterial lesion. DESIGN: A retrospective study. MATERIALS AND METHODS: Over 3 years, 17 patients presented with blue fingers secondary to an ipsilateral proximal vascular lesion. These have been managed using transluminal angioplasty (14) and arterial stenting (five), combined with embolectomy (two) and anticoagulation (three)/anti-platelet therapy (14). RESULTS: All the patients were treated successfully. There have been no further symptomatic embolic episodes originating from any of the treated lesions, and no surgical amputations. Complications were associated with the use of brachial arteriotomy for vascular access. CONCLUSIONS: Endovascular techniques are safe and effective in the management of upper limb embolic phenomena associated with an ipsilateral proximal focal vascular lesion.

Adult↗
PubMed1999

Aortoiliac stenting, determinants of clinical outcome.

OBJECTIVES: To determine predictors of clinical outcome in stenting aortoiliac disease. DESIGN: Prospective/retrospective study. MATERIALS AND METHODS: One hundred and forty patients (163 limbs) underwent iliac artery stenting in the period 1994-1997. Ninety-eight occlusions and 65 stenoses were treated, either with primary stenting (n = 129) or after failed angioplasty (n = 34). Median follow-up 18 months (1-66). Factors analysed for their effect on outcome were: gender, age, Fontaine stage, ABI, lesion type/length/site, primary or secondary stenting, stent type, BP, smoking, diabetes, aspirin, cholesterol, residual gradient, overhanging and run-off. RESULTS: The immediate success was 95%. The primary successful clinical outcome was 90% at 12 months and 84% at 36 months; the primary-assisted successful clinical outcome was 95% at 12 months and 91% at 36 months and the secondary successful clinical outcome was 92% at 12 months and 87% at 36 months. Adverse factors affecting outcome were: residual pressure gradient (> 10 mmHg) and no treatment with aspirin (p < 0.05). Major complications occurred in 18% of patients with a re-intervention in 8%. The 30-day mortality was 5.5%. CONCLUSIONS: Stenting for aortoiliac occlusive disease has good short and long term clinical success, with low morbidity and mortality. Factors that might improve results further are ensuring that patients are taking aspirin and any residual pressure gradient is abolished.

Aged↗
PubMed1999

Population health environmental indicators: ecologic monitoring of environment-related health and disease trends.

BACKGROUND: Current State of the Environment (SoE) reporting focuses primarily on indicators directly related to the physical environment such as climate, and air, water and soil quality. As the environment has both direct and indirect effects on human health, an opportunity exists to include environment-related human disease indicators as an SoE indicator theme. OBJECTIVE: To develop a set of population health environmental indicators (PHEIs, phi s) that can illustrate environment-related disease (ERD) trends at the population level. METHODS: A literature review was conducted on environmental health monitoring and the current knowledge of environmental effects on human health. Key PHEIs were identified and routine health data collections accessed and analysed to illustrate temporal and geographic trends. RESULTS: Diseases with an environmental aetiology are tabulated and examples are given of the type and range of PHEIs that can be developed for an Australian geographic area. CONCLUSIONS: Illustrating environmental degradation in terms of resultant human diseases is a potent tool for promoting environmental protection measures. This paper examines a range of PHEIs that may be used as indicators of both environmental disease and environmental quality. IMPLICATIONS: PHEIs could be developed as a useful SoE indicator theme, and as a tool to help foster the convergence which is occurring between environmental health and public health fields.

Australia↗
PubMed1998

Alcohol education in licensed premises using brief intervention strategies.

AIMS: The aim of this feasibility study is to present a description of a new approach based on alcohol brief intervention strategies to intervene with at-risk drinkers in licensed premises. DESIGN: The data presented are from a convenience sample of tavern patrons. SETTING: The intervention called Operation Drinksafe was conducted on 75 occasions in 67 licensed premises in an Australian rural area. PARTICIPANTS: There were 2761 voluntary participants who were provided with a personal risk assessment of their alcohol use. MEASUREMENTS: The main measurements were the Alcohol Use Disorders Identification Test (AUDIT) combined with a blood alcohol concentration (BAC) reading. FINDINGS: The median AUDIT score was 11.0, with 53% scoring in the hazardous range and 25% in the harmful range. For binge drinking, almost two-thirds (62%) of males drank six or more drinks once a week or more compared to 29% of females. Median BAC was 0.03 mg/100 ml with 11% of males above 0.10. Regression analysis revealed that significant predictors of alcohol-related injury were being aged less than 30 years, forgetting the previous night, having had another person express concern about your drinking, and binge drinking weekly or more. CONCLUSIONS: The program had high acceptance among licensees and their patrons. Patrons who are ready to change their at-risk drinking behaviour may benefit from this type of minimal intervention when presented in an interesting way in their drinking environments.

Adult↗
PubMed1998

Burden of disease. Methods of calculating disability from mental disorder.

BACKGROUND: The Global Burden of Disease studies are important because they encompass morbidity as well as mortality. Burden due to morbidity is calculated from incidence, duration and disability. There is a dearth of epidemiological measurements of disability. METHOD: Data from a quasi-community sample (n = 1364) were analysed. Diagnoses of mental and physical disorders, and reports of disability, were based on established methods. RESULTS: The disabilities reported in mental and physical disorders were comparable. Disability was correlated with comorbidity. The disability in mental disorders was examined by three methods: pure disorders, main problem and regression. It appears that major depression and substance disorder weights were overestimated, and anxiety disorder weights were underestimated in the Global Burden of Disease studies. CONCLUSIONS: A method for disentangling the effects of concurrent comorbidity is presented. The size of burden attributed to mental disorders is of potential benefit for funding mental health services, It is important that we get the estimates right.

Adult↗
PubMed1997

An outbreak of Norwalk virus gastroenteritis following consumption of oysters.

In August 1996, an outbreak of Norwalk virus gastroenteritis occurred among south-east Queensland and northern New South Wales residents over a four week period. Ninety-two of the 97 cases detected were confirmed as having consumed raw oysters within three days prior to developing the illness. No other food items or beverages were significantly associated with the illness. Environmental investigations indicated the Terranora Broadwater, Tweed Heads as the origin of the contaminated oysters. However, the primary source of Norwalk virus could not be verified. Oysters and other shellfish appear to be a common vehicle for transmission of this virus. This outbreak and the more recent hepatitis A outbreak associated with Wallis Lake oysters, highlight the susceptibility of oysters to environmental contamination and the urgent need for stricter quality control procedures. This report details the epidemiological, microbiological and environmental findings from an outbreak investigation conducted jointly by the Queensland and New South Wales health authorities.

Adolescent↗
PubMed1997

Prospective audit of surgery for varicose veins.

BACKGROUND: Recent reports have demonstrated a high recurrence rate following varicose vein surgery. It has been suggested that this is due to inadequate surgery. This has been assessed by a prospective surgical audit. METHODS: Fifty limbs in 33 patients awaiting varicose vein surgery were examined before operation and 6 weeks after operation. A duplex scanner was used to detect sites of venous incompetence. RESULTS: Eighteen operations were performed for recurrent disease, 38 limbs had an incompetent connection between the long saphenous vein or another superficial vein and the common femoral vein in the groin, and 11 limbs had saphenopopliteal incompetence. Following surgery, persisting incompetence existed in seven limbs in the groin and eight limbs in the popliteal fossa; this was due to inadequate surgery in 13 of 15 cases. Thirty-four operations were performed by trainees who were responsible for 14 of the 15 cases of persisting incompetence in the groin or popliteal fossa. CONCLUSION: Improved surgical technique and training is required to reduce recurrence following varicose vein surgery.

Adult↗
PubMed1997

Changes in iron status during weight loss with very-low-energy diets.

For several decades, very-low-energy diets (VLEDs) have been used by obese individuals to achieve weight loss. During the weight loss, patients often have dramatic drops in circulating thyroid hormone concentrations and experience cold intolerance. Because poor iron status is known to alter thermogenesis, we investigated the possibility that iron intake interacts with energy intake during weight loss in obese individuals. The effects on indicators of iron and thyroid status of increasing the iron content of a VLED from 18 to 27 mg/d during 12 wk of a VLED were compared with the effects on the same indicators of increasing energy intake from 1752 kJ(420 kcal) to 3347 kJ(800 kcal)/d. Although all VLED groups initially had 30% declines in plasma transferrin saturation, increases in plasma ferritin concentrations, and decreases in plasma thyroid hormone concentrations, patients who received iron supplementation had significantly higher circulating concentrations of triiodothyronine and thyroxine at the end of the VLED than did patients who received only the recommended dietary allowance of iron. The patients who received iron supplementation also had a more rapid return of iron indicators to normal values over the course of the VLED. The transitory fall in iron delivery to bone marrow was not associated with anemia. These data suggest that higher thyroid hormone concentrations can be maintained during VLEDs that provide higher iron intakes.

Adult↗
PubMed1996

The management and outcome of critical limb ischaemia in diabetic patients: results of a national survey. Audit Committee of the Vascular Surgical Society of Great Britain and Ireland.

It is generally considered that the outcome from critical limb ischaemia (CLI) in people with diabetes is inferior to that in non-diabetic patients. However, excellent results have been reported in diabetic people with the use of bypass surgery to pedal arteries. Data from a prospective national survey on CLI have been analysed to compare surgical practice and outcome from CLI in diabetic and non-diabetic populations. Of 679 limbs included in the survey, 204 (30%) were in diabetic patients. Thirty-seven (18%) of diabetic limbs were treated by primary amputation compared to 43 (9%) in non-diabetics (p = 0.0013). Revascularization was the primary treatment intention in 127 (62.3%) of diabetic limbs compared to 342 (72%) in non-diabetics (p = 0.01). Bypass to pedal arteries was reported in only 2 (1%) diabetic patients. The limb salvage rate in diabetic patients was 60%, compared to 72.5% for non-diabetic patients (p = 0.0013). The mortality rates were 15% and 12% in diabetic and non-diabetic patients, respectively (NS). These results confirm that in the UK and Ireland diabetic patients with CLI fare considerably worse than do people without diabetes. The results may be improved if more pedal artery reconstructions were performed.

Adult↗
PubMed1996

Histologic and immunohistochemical features in biopsy sites in which bovine collagen matrix was used for hemostasis.

BACKGROUND: Bovine collagen matrix (Helistat and Helatene), which is used primarily for hemostasis, decreases wound contracture in skin biopsy sites and promotes wound granulation. OBJECTIVE: Our purpose was to evaluate excision specimens of previous biopsy sites to determine whether there are histologic differences between cases in which bovine collagen matrix was used for hemostasis and those in which it was not used. METHODS: Thirty-two diagnostic punch biopsies were done with hemostasis obtained with bovine collagen matrix in 24 biopsies and by pressure alone in eight. The biopsy sites were reexcised at various time intervals, and the histologic and immunohistochemical features were evaluated and compared. RESULTS: In specimens in which collagen matrix was used, migration of stromal and epithelial cells along the bovine collagen matrix was evident by 2 days and had progressed rapidly by 4 days. Around and within the matrix hyaluronic acid increased during the first 8 to 10 days. Initially stromal cells stained with CD34 and reticulum fibers were present at 8 to 10 days. AT 12 to 15 days, factor XIIIa+ stromal cells were present within the matrix, and host collagen fibers were present and well-oriented within the degenerating matrix. Biopsy specimens allowed to heal without the matrix showed a delayed and an uneven increase in hyaluronic acid. Furthermore, the granulation tissue within the dermis showed no organization with a persistent acute inflammatory infiltrate and increased muscle actin-positive stromal cells as scar formation proceeded. CONCLUSION: Bovine collagen products appear to provide a matrix that promotes thrombosis. The collagen matrix also promotes migration and attachment of stomal and epithelial cells, thereby organizing and accelerating wound healing.

Actins↗
PubMed1996

Iron and thermoregulation: a review.

Poor temperature regulation in both human and animal models has been associated with iron deficiency anemia. The review examines the evidence for causality in both animals and humans, as well as provides an overview of temperature regulation in homeotherms. A number of investigations conclude that anemia is a central component of the inability of iron-deficient individuals to temperature regulate when they are cold stressed. This is apparently due to effects both on heat production and heat loss rates. The former is related to poor thyroid function in iron deficiency and the latter to the competing demands for tissue oxygenation vs. decreased flood flow to minimize heat losses to the environment. Future research needs are outlined that require integration of endocrinology, physiology, and nutrition disciplines.

Anemia, Iron-Deficiency↗
PubMed1996

Evaluation of an economical sunlamp that emits a near solar UV power spectrum for conducting photoimmunological and sunscreen immune protection studies.

Expense and inconvenience have restricted the use of the filtered xenon are lamp (solar simulator) as a UV source for conducting large-scale animal studies. Because sunscreen immunoprotective levels are significantly affected by the UV power spectrum of the source it is imperative that a solar simulating source be used for accurate measurements of sunscreen protection levels that are relevant to human LV exposures from sunlight. However, relatively inexpensive sunlamps, e.g. the UVA-340, that emit a UV power spectrum similar to that of a solar simulator are available. Unlike FS-type UVB sunlamps, which have a significant amount of effective immunosuppressive non-solar UV energy at wavelengths below 295 nm, the immunosuppression effectiveness spectrum of UVA-340 sunlamps was nearly identical to that of a solar simulator. The purpose of this study was to evaluate this sunlamp for conducting photoimmunological and sunscreen immune protection studies. Groups of C3H mice were exposed to a range of UVA-340 sunlamp doses (0.25 kJ/m2 to 20.0 kJ/m2) to establish a dose-response curve and determine the minimum immune suppression dose (MISD) for iduction of local-type suppression of contact hypersensitivity (CH). The MISD, defined as the lowest UV dose given to produce approximately 50% suppression of the CH response in mice, was determined to be 1.0 kJ/m2 for UVA-340 sunlamps. Immune protection tests on four marketed sunscreen lotions (sun protection factors [SPF] 4, 8, 15 and 30) were then conducted with UVA-340 sunlamps using MISD as the endpoint. The immune protection factors for these sunscreens were equivalent to the level of protection predicted by their labeled SPF. These results are similar to those we have previously obtained using a solar simulator. We conclude from these data that the immunosuppressive effects of UVA-340 sunlamps are similar to those of a solar simulator; however, further studies are needed to determine if UVA-340, or similar, sunlamps are a viable alternative to the solar simulator for conducting large-scale animal experiments that require a relevant UV solar spectrum.

Adjuvants, Immunologic↗