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Jenny Thomas

Publications and source records attributed to Jenny Thomas.

10 recordsLinked to original sources

B-vitamins reduce plasma levels of beta amyloid.

Elevated plasma homocysteine (tHcy) is a risk factor for Alzheimer's disease (AD), and thus B vitamins may have a role in the prevention of AD. The objective of this study was to determine if tHcy lowering vitamins decrease the circulating levels of A-beta protein 1-40 (A beta 40). We randomized 299 older men to treatment with 2mg of folate, plus 25mg of B6 and 400 microg of B12, or placebo. After 2 years of treatment the mean (S.E.) increase of A beta 40 was 7.0 pg/ml (8.4) in the vitamin group (4.9%), and 26.8 pg/ml (7.7) (18.5%) in the placebo group. We conclude that B vitamins may decrease the plasma level of A beta 40 and have a role in the prevention of AD.

Aged↗

Efficacy of B vitamins in lowering homocysteine in older men: maximal effects for those with B12 deficiency and hyperhomocysteinemia.

BACKGROUND AND PURPOSE: A higher plasma concentration of total homocysteine (tHcy) is associated with a greater risk of cardiovascular events. Previous studies, largely in younger individuals, have shown that B vitamins lowered tHcy by substantial amounts and that this effect is greater in people with higher tHcy and lower folate levels. METHODS: We undertook a 2-year, double-blind, placebo-controlled, randomized trial in 299 men aged > or =75 years, comparing treatment with a daily tablet containing 2 mg of folate, 25 mg of B6, and 400 microg of B12 or placebo. The study groups were balanced regarding age (mean+/-SD, 78.9+/-2.8 years), B vitamins, and tHcy at baseline. RESULTS: Among the 13% with B12 deficiency, the difference in mean changes in treatment and control groups for tHcy was 6.74 micromol/L (95% CI, 3.94 to 9.55 micromol/L) compared with 2.88 micromol/L (95% CI, 0.07 to 5.69 micromol/L) for all others. Among the 20% with hyperhomocysteinaemia, the difference between mean changes in treatment and control groups for men with high plasma tHcy compared with the rest of the group was 2.8 micromol/L (95% CI, 0.6 to 4.9 micromol/L). Baseline vitamin B12, serum folate, and tHcy were significantly associated with changes in plasma tHcy at follow-up (r=0.252, r=0.522, and r=-0.903, respectively; P=0.003, <0.001, and <0.001, respectively) in the vitamin group. CONCLUSIONS: The tHcy-lowering effect of B vitamins was maximal in those who had low B12 or high tHcy levels. Community-dwelling older men, who are likely to be deficient in B12 or have hyperhomocysteinemia, may be most likely to benefit from treatment with B vitamins.

Aged↗

Pharmacokinetics and efficacy of ropivacaine for continuous epidural infusion in neonates and infants.

INTRODUCTION: The primary objective of this noncomparative study was to evaluate the pharmacokinetics of ropivacaine during a 48-72-h continuous epidural infusion of ropivacaine in children under 1 year. The secondary objectives were to assess efficacy and safety. METHODS: Neonates and infants (ASA I-III, gestational age > or =37 weeks, > or =2.5 kg, scheduled for major abdominal or thoracic surgery) were included and separated into age groups: 0-30 (neonate), 31-90, 91-180, and 181-365 days. Ethics committee approval and informed parental consent were obtained before inclusion. An epidural catheter was introduced under general anesthesia at the appropriate dermatomal level. An initial bolus dose (0.9-2.0 mg.kg(-1) of ropivacaine 0.2%) was followed by an epidural infusion (0.2 mg.kg(-1).h(-1) for infants <180 days or 0.4 mg.kg(-1).h(-1) for infants >180 days). Plasma samples were collected every 12 h from 24 h, and on termination of the epidural infusion. Postoperative pain was evaluated using both the Objective Pain Scale and a four-graded descriptive scale. RESULTS: Forty-five infants, median age 116 (0-362) days, were included. Forty-three and 19 patients received an infusion for at least 48 and 72 h, respectively. Satisfactory analgesia was provided in the majority, only 20 patients were given supplementary medication during the infusion. In all age groups, plasma concentrations of unbound ropivacaine leveled at 24 h, without any further increase at 48 and 72 h. Because of lower clearance of unbound ropivacaine in neonates (mean 33 ml.min(-1).kg(-1)) than in infants above the age of 30 days (80, 124, and 163 ml.min(-1).kg(-1), respectively, in the age groups 31-90, 91-180, and 180-365 days), unbound ropivacaine concentrations at the end of infusion were higher in neonates [median 0.10 mg.l(-1) (0.04-0.21 mg.l(-1))] than in infants >30 days [median 0.03 mg.l(-1) (0.003-0.10 mg.l(-1))]. CONCLUSION: Epidural infusions (0.2-0.4 mg.kg(-1).h(-1) ropivacaine) provided satisfactory pain relief in neonates and infants under 1 year. As plasma concentrations of unbound ropivacaine were not influenced by the duration of the infusion, ropivacaine can be safely used for postoperative epidural infusion for 48-72 h. Levels of unbound ropivacaine were higher in the neonates than in the infants, but were below threshold concentrations for CNS toxicity in adults (> or =0.35 mg.l(-1)). This should not preclude the use of ropivacaine infusions in neonates but suggests a need for caution during the first weeks of life.

Aging↗

Should older people in residential care receive vitamin D to prevent falls? Results of a randomized trial.

OBJECTIVES: To determine whether vitamin D supplementation can reduce the incidence of falls and fractures in older people in residential care who are not classically vitamin D deficient. DESIGN: Randomized, placebo-controlled double-blind, trial of 2 years' duration. SETTING: Multicenter study in 60 hostels (assisted living facilities) and 89 nursing homes across Australia. PARTICIPANTS: Six hundred twenty-five residents (mean age 83.4) with serum 25-hydroxyvitamin D levels between 25 and 90 nmol/L. INTERVENTION: Vitamin D supplementation (ergocalciferol, initially 10,000 IU given once weekly and then 1,000 IU daily) or placebo for 2 years. All subjects received 600 mg of elemental calcium daily as calcium carbonate. MEASUREMENTS: Falls and fractures recorded prospectively in study diaries by care staff. RESULTS: The vitamin D and placebo groups had similar baseline characteristics. In intention-to-treat analysis, the incident rate ratio for falling was 0.73 (95% confidence interval (CI)=0.57-0.95). The odds ratio for ever falling was 0.82 (95% CI=0.59-1.12) and for ever fracturing was 0.69 (95% CI=0.40-1.18). An a priori subgroup analysis of subjects who took at least half the prescribed capsules (n=540), demonstrated an incident rate ratio for falls of 0.63 (95% CI=0.48-0.82), an odds ratio (OR) for ever falling of 0.70 (95% CI=0.50-0.99), and an OR for ever fracturing of 0.68 (95% CI=0.38-1.22). CONCLUSION: Older people in residential care can reduce their incidence of falls if they take a vitamin D supplement for 2 years even if they are not initially classically vitamin D deficient.

Accidental Falls↗

Anaesthetic consequences for a child with complex multilevel airway obstruction -- recommendations for avoiding life-threatening sequelae.

A boy with a suspected lymphoid malignancy presented with gross head and neck lymphadenopathy, a middle mediastinal mass, and rapidly worsening airway obstruction. General anaesthesia was required for definitive histopathological diagnosis. The combination of nasopharyngeal obstruction, malignant infiltration of the tonsils and pharynx, laryngeal displacement, and potential tracheal compression put this patient at extreme risk for perioperative airway complications. Risk assessment, and the impact of anaesthesia on pharyngeal neuromechanical function and mediastinal masses are discussed. Caution with volatile anaesthetic agents is recommended in the patient with an inherently unstable pharynx and/or trachea, in whom airway patency relies on a spontaneously breathing technique and intact airway reflexes.

Airway Obstruction↗

Using action learning to support and develop the role of matrons.

This article describes the action learning approach used by West Hertfordshire Hospitals NHS Trust to implement a programme of support and development for its 12 matrons. The programme has not only developed the matrons' confidence and abilities, but has enabled them to work together on issues that affect the organisation as a whole, rather than tackling them individually.

Humans↗