Intraocular Pressure Rise in Subjects with and without Glaucoma during Four Common Yoga Positions

Purpose

To measure changes in intraocular pressure (IOP) in association with yoga exercises with a head-down position.

Methods

The single Center, prospective, observational study included 10 subjects with primary open-angle glaucoma and 10 normal individuals, who performed the yoga exercises of Adho Mukha Svanasana, Uttanasana, Halasana and Viparita Karani for two minutes each. IOP was measured by pneumatonometry at baseline and during and after the exercises.

Results

All yoga poses were associated with a significant (P<0.01) rise in IOP within one minute after assuming the yoga position. The highest IOP increase (P<0.01) was measured in the Adho Mukha Svanasana position (IOP increase from 17±3.2 mmHg to 28±3.8 mmHg in glaucoma patients; from 17±2.8 mmHg to 29±3.9 mmHg in normal individuals), followed by the Uttanasana position (17±3.9 mmHg to 27±3.4 mmHg (glaucoma patients) and from 18±2.5 mmHg to 26±3.6 mmHg normal individuals)), the Halasana position (18±2.8 mmHg to 24±3.5 mmHg (glaucoma patients); 18±2.7 mmHg to 22±3.4 mmHg (normal individuals)), and finally the Viparita Kirani position (17±4 mmHg to 21±3.6 mmHg (glaucoma patients); 17±2.8 to 21±2.4 mmHg (normal individuals)). IOP dropped back to baseline values within two minutes after returning to a sitting position. Overall, IOP rise was not significantly different between glaucoma and normal subjects (P = 0.813), all though glaucoma eyes tended to have measurements 2 mm Hg higher on average.

Conclusions

Yoga exercises with head-down positions were associated with a rapid rise in IOP in glaucoma and healthy eyes. IOP returned to baseline values within 2 minutes. Future studies are warranted addressing whether yoga exercise associated IOP changes are associated with similar changes in cerebrospinal fluid pressure and whether they increase the risk of glaucoma progression.

Trial Registration

ClinicalTrials.gov #{"type":"clinical-trial","attrs":{"text":"NCT01915680","term_id":"NCT01915680"}}NCT01915680     

Survival of Plant Tissue at Super-Low Temperature VI. Effects of Cooling and Rewarming Rates on Survival

The survival rates of the cortical parenchymal cells of mulberry tree were determined as a function of cooling and rewarming rates. When cooling was carried out slowly at 1° to 15° per minute, all of the cells still remained viable even when rewarmed either rapidly or slowly. Survival rates gradually decreased to zero as the cooling rate increased from about 15° to 2000° per minute. In the intermediate cooling rates, when the cells were cooled at the rates lower than 14° per minute, from −2.2° to about −10°, these cells could survive subsequent rapid cooling and rewarming.

However, at cooling rates above 1000° per minute and with rapid rewarming, the effect of cooling rate reversed and survival increased, reaching a maximum at about 200,000° per minute. As the cooling rate increased above 15° per minute, survival rates became increasingly dependent on the rewarming rate, with rapid rewarming becoming less deleterious than slow rewarming.

The temperature range at which damage occurred during rewarming following removal from liquid nitrogen and in which growth rate of ice crystallization was greatest, was −30° to −40°. The survival rates even in the prefrozen cells at −30° decreased considerably by keeping them at −30° for 10 minutes after removal from liquid nitrogen. This fact indicates that intracellular freezable water remains to some degree even in the prefrozen cells at −30°. After removal from liquid nitrogen, all cells retained their viability, when they were passed rapidly through a temperature range between −50° and −2.5° within about 2 seconds, namely at the rates greater than 1000° per minute.

These observations are explained in terms of the size of the crystals formed within the cortical cells.

     

Characterising the nationwide burden and predictors of unkept outpatient appointments in the National Health Service in England: A cohort study using a machine learning approach

BackgroundUnkept outpatient hospital appointments cost the National Health Service £1 billion each year. Given the associated costs and morbidity of unkept appointments, this is an issue requiring urgent attention. We aimed to determine rates of unkept outpatient clinic appointments across hospital trusts in the England. In addition, we aimed to examine the predictors of unkept outpatient clinic appointments across specialties at Imperial College Healthcare NHS Trust (ICHT). Our final aim was to train machine learning models to determine the effectiveness of a potential intervention in reducing unkept appointments.Methods and findingsUK Hospital Episode Statistics outpatient data from 2016 to 2018 were used for this study. Machine learning models were trained to determine predictors of unkept appointments and their relative importance. These models were gradient boosting machines. In 2017–2018 there were approximately 85 million outpatient appointments, with an unkept appointment rate of 5.7%. Within ICHT, there were almost 1 million appointments, with an unkept appointment rate of 11.2%. Hepatology had the highest rate of unkept appointments (17%), and medical oncology had the lowest (6%). The most important predictors of unkept appointments included the recency (25%) and frequency (13%) of previous unkept appointments and age at appointment (10%). A sensitivity of 0.287 was calculated overall for specialties with at least 10,000 appointments in 2016–2017 (after data cleaning). This suggests that 28.7% of patients who do miss their appointment would be successfully targeted if the top 10% least likely to attend received an intervention. As a result, an intervention targeting the top 10% of likely non-attenders, in the full population of patients, would be able to capture 28.7% of unkept appointments if successful. Study limitations include that some unkept appointments may have been missed from the analysis because recording of unkept appointments is not mandatory in England. Furthermore, results here are based on a single trust in England, hence may not be generalisable to other locations.ConclusionsUnkept appointments remain an ongoing concern for healthcare systems internationally. Using machine learning, we can identify those most likely to miss their appointment and implement more targeted interventions to reduce unkept appointment rates.

Sion Phillpott-Morgan and co-workers study occurrence and possible predictors of unkept outpatient appointments in the UK.     

Comparison of criteria derived by government and patients for evaluating general practitioner services.

A study was carried out to see whether patients'' criteria of good health care in general practice were different from those of the government and doctors. A total of 711 patients in a semirural group practice evaluated the importance of 20 criteria describing different facets of care. Half the criteria were derived from Promoting Better Health (health education, easy to change doctors, all children vaccinated, health checks for adults and children under 5, regular screening for cancer, woman doctor available, doctor goes on courses, well decorated premises, convenient surgery times); the other 10 were taken from a preliminary interview study of 24 patients (staff friendly and know me, doctor listens and sorts out problems, same doctor for consultations, nurse on premises, appointments available within 48 hours, waiting time less than 20 minutes, small surgery premises, tests available at surgery). Questionnaires containing 10 pairs of criteria assigned by computer were drawn up and patients asked to give their preference in each pair. The number of times each criterion was preferred was scored and its comparative importance ranked. The three criteria most highly ranked by all patients were having a doctor who listens, having a doctor who sorts out problems, and usually seeing the same doctor (all criteria originated by patients). The three least highly valued were health education, being able to change doctor easily, and well decorated and convenient premises (all criteria originated by the government). The criteria originated by patients as a group scored significantly more highly than those originated by government as a group. In a more competitive general practice environment, in which doctors will be more inclined to satisfy the wishes of patients, officially supported indicators of good quality care might not get the encouragement that the government and doctors think that they deserve.     

Response to Rimiterol and Salbutamol Aerosols Administered by Intermittent Positive-pressure Ventilation

The bronchodilator and cardiac effects produced by aerosols of 0·5% salbutamol and 0·5% and 1% rimiterol administered for three minutes in 40% oxygen by intermittent positive-pressure ventilation (I.P.P.V.) were compared in 15 asthmatic patients. Salbutamol and both the concentrations of rimiterol were equipotent in peak bronchodilator effect, but salbutamol had a significantly longer duration of bronchodilator action. There was significantly less increase in heart rate after rimiterol than after salbutamol. Aerosols of 0·5% rimiterol, 0·5% salbutamol, and saline were administered by I.P.P.V. to 10 normal volunteers. There was no difference between the mean heart rates after 0·5% rimiterol and saline but a highly significant increase in mean heart rate was observed after 0·5% salbutamol. It was concluded that 0·5% rimiterol was an effective short-acting bronchodilator drug with little or no cardiac beta₁-adrenergic activity when administered for three minutes by I.P.P.V. in 40% oxygen.     

Can Children Discriminate Sugar-Sweetened from Non-Nutritively Sweetened Beverages and How Do They Like Them?

Background

Replacement of sugar-sweetened by non-nutritively sweetened beverages or water may reduce excess weight gain in children. However, it is unclear whether children like non-nutritively sweetened beverages as much as sugar-sweetened beverages. We examined whether children could taste a difference between non-nutritively sweetened beverages and matching sugar-sweetened beverages, and which of the two types of beverage they liked best.

Methods

89 children aged 5 to 12 tasted seven non-nutritively sweetened beverages and matching sugar-sweetened beverages, for a total of 14 beverages. We used Triangle tests to check their ability to discriminate between the matched versions, and a 5-point scale to measure how much the children liked each individual beverage.

Results

Overall, 24% of children appeared to be genuinely capable of distinguishing between non-nutritively sweetened and sugar-sweetened beverages. The mean ± SD score for how much the children liked the non-nutritively sweetened beverages was 3.39±0.7 and that for the sugar-sweetened beverages 3.39±0.6 (P = 0.9) on a scale running from 1 (disgusting) to 5 (delicious). The children preferred some beverages to others irrespective of whether they were sugar-sweetened or non-nutritively sweetened (P = 0.000). Children who correctly identified which of three drinks contained the same sweetener and which one was different also showed no preference for either type.

Conclusion

We found that about one in four children were able to discriminate between non-nutritively sweetened and sugar-sweetened beverages but children liked both varieties equally. Non-nutritively sweetened beverages may therefore be an acceptable alternative to sugar-sweetened beverages although water remains the healthiest beverage for children.     

Higher ventilatory responses during and after passive walking-like leg movement in older individuals

Background

Minute ventilation (V·E) during walking has been shown to be higher in older individuals than in young individuals, but the mechanisms underlying the higher ventilatory response is unclear. Central command and peripheral neural reflex are important neural control mechanisms underlying ventilatory response during exercise. Passive leg movement has been used to exclude the influence of central command due to the lack of voluntary activation of muscles. The aim of the present study was to compare the ventilatory response during and after passive walking-like leg movement (PWM) in young and older individuals.

Methods

Eight young subjects (20 ± 2 years) and seven older subjects (70 ± 1 years) participated in this study. Subjects spent 7 minutes in a quiet standing (QS) position. Thereafter, they performed 14-minute rhythmic PWM at 1 Hz and this was followed by 7 minutes of QS.

Results

V·E values during pre-PWM QS were calculated as 1-minute averages using data obtained between 5 and 6 minutes. V·E values at pre-PWM QS in the young and older groups were 8.4 ± 2.1 and 7.5 ± 1.2 l/minute, respectively. V·E values increased significantly at the first minute of PWM to 11.4 ± 2.2 and 10.4 ± 2.5 l/minute in the young and older groups, respectively (P <0.001). In the young group, V·E at the last minute of PWM (9.2 ± 2.0 l/minute) was not significantly different from that at pre-PWM QS due to a decline in V·E, whereas V·E at the last minute of PWM in the older group (9.4 ± 2.2 l/minute) was still significantly higher (P <0.01). On the other hand, V·E at the first minute of post-PWM QS (7.2 ± 1.8 l/minute) was significantly lower than that during pre-PWM QS in the young group (P <0.05) but not in the older group.

Conclusions

Ventilatory response during and after PWM is higher in older individuals than in young individuals. This may be associated with a mechanism(s) other than central command. Our findings may explain part of the higher V·E response while walking in older individuals.     

Factors protective against retinopathy in insulin-dependent diabetics free of retinopathy for 30 years

To investigate which factors might protect against the development of retinopathy 40 insulin-dependent diabetics who had remained free from retinopathy despite diabetes of long duration (mean±1 SD 30±10 years) were compared with 40 patients who had background and 47 who had proliferative retinopathy (mean durations of disease 16±5 and 19±5 years respectively). The three groups had had similar mean ages at onset of diabetes. The mean of all postprandial blood glucose measurements at hospital clinics from diagnosis of diabetes to detection of retinopathy, or to the most recent negative eye examination, was 9·9±2·1 mmol/l (178±38 mg/100 ml) in the group with no retinopathy, 11·8±2·1 mmol/l (213±38 mg/100 ml) in those with background retinopathy, and 12·4±2·1 mmol/l (223±38 mg/100 ml) in those with proliferative retinopathy (p <0·0001). This difference was not reflected in present concentrations of haemoglobin A_1C, probably because glycaemic control had been improved after the development of retinopathy. In the groups with background and proliferative retinopathy there were significant negative correlations between mean blood glucose concentrations and the number of years that had elapsed from diagnosis of diabetes to detection of retinopathy, suggesting that the development of both grades of retinopathy depends on the degree and duration of glycaemic exposure.The patients with no retinopathy had attended clinic more frequently (p <0·025), more of them had required emergency hospital treatment for hypoglycaemia (p <0·0025), and they tended to have had a lower prevalence of hyperglycaemic coma than the other groups. Although mean percentage ideal body weight and diastolic blood pressure were lower in the patients with no retinopathy at the time of study, mean body weight, blood pressure, and the prevalence of smoking in the years before the development of retinopathy had been similar in all groups, suggesting that these did not influence the development of retinopathy.     

Role of Metabolites in the Reversible Light Activation of Pyruvate, Orthophosphate Dikinase in Zea mays Mesophyll Cells in Vivo

Whole leaf and mesophyll cell concentrations of pyruvate, phosphoenolpyruvate (PEP), ATP, and ADP were determined in Zea mays during the reversible light activation of pyruvate, orthophosphate dikinase in vivo. Mesophyll cell levels of the four metabolites were estimated by extrapolation from values in freeze-quenched leaf samples that were fractionated by differential filtration through nylon mesh nets (adapted from M Stitt, HW Heldt [1985] Planta 164: 179-188). During the 3 minutes required for complete light activation of dikinase, pyruvate levels in the mesophyll cell decreased (from 166 ± 15 to 64 ± 10 nanomoles per milligram of chlorophyll [nmol/mg Chl]) while PEP levels increased (from 31 ± 4 to 68 ± 4 nmol/mg Chl, with a transient burst of 133 ± 16 nmol/mg Chl at 1 minute). Mesophyll cell levels of ATP increased (from 22 ± 4 to 48 ± 3 nmol/mg Chl) and ADP levels decreased (from 16 ± 4 to 7 ± 6 nmol/mg Chl) during the first minute of illumination. Upon darkening of the leaf and inactivation of dikinase, pyruvate levels initially increased in the mesophyll (from 160 ± 30 to a maximum of 625 ± 40 nmol/mg Chl), and then slowly decreased to about the initial value in the light over an hour. PEP levels dropped (from 176 ± 5 to 47 ± 3 nmol/mg Chl) in the first 3 minutes and remained low for the remainder of the dark period. Mesophyll levels of ATP and ADP rapidly decreased and increased, respectively, about twofold upon darkening. The trends observed for these metabolite levels in the mesophyll cell during the light/dark regulation of pyruvate, orthophosphate dikinase activity suggest that pyruvate and PEP do not play a major role in vivo in regulating the extent of light activation (dephosphorylation) or dark inactivation (ADP-dependent threonyl phosphorylation) of dikinase by its bifunctional regulatory protein. While the changes in ADP levels appear qualitatively consistent with a regulatory role for this metabolite in the light activation and dark inactivation of dikinase, they are not of a sufficient magnitude to account completely for the tenfold change in enzyme activity observed in vivo.     

Health promotion in the general practice consultation: a minute makes a difference.

OBJECTIVE--To see whether extending appointment length from seven and a half minutes or less to 10 minutes per patient would increase health promotion in general practice consultations. DESIGN--Controlled trial of 10 minute appointments. Consultations were compared with control surgeries in which the same doctors booked patients at their normal rate (median six minutes per patient). SETTING--10 general practices in Nottinghamshire. SUBJECTS--16 general practitioners were recruited. Entry criteria were a booking rate of eight or more patients an hour, a wish for longer consultations, and plans to increase appointment length. MAIN OUTCOME MEASURES--Duration of consultations; recording of blood pressure, weight, and cervical cytology in the medical record; recording of advice about smoking, alcohol, diet, exercise, and immunisation in the medical record; reporting of the above activities by patients. RESULTS--Mean consultation times were 8.25 minutes in the experimental sessions and 7.04 and 7.16 minutes in the control sessions. Recording of blood pressure, smoking, alcohol consumption, and advice about immunisation was significantly more frequent in the experimental sessions, and the proportion of consultations in which one or more items of health education were recorded in the medical notes increased by an average of over 6% in these sessions. Patients more often reported discussion of smoking and alcohol consumption and coverage of previous health problems in the experimental sessions. There was little change in discussion of exercise, diet, and weight or cervical cytology activity. CONCLUSIONS--Shortage of time is a major factor in general practitioners'' failure to realise their potential in health promotion. General practice should be organised so that doctors can run 10 minute appointment sessions.     

Impaired renal functional reserve and albuminuria in essential hypertension

The stimulatory effects of an infusion of amino acids on glomerular filtration rate has previously been used to measure renal functional reserve and detect glomerular hyperfiltration. Thirty four patients with mild to moderate essential hypertension and seemingly normal renal function and 22 healthy controls were given infusions of amino acids to investigate whether renal functional reserve is reduced in essential hypertension and to detect patients at risk of renal damage. Although basal creatinine clearance increased after the infusion of amino acids in the controls (mean 27·9 ml/min; 95% confidence interval 18·2 to 37·6), the overall change was lower in the patients (mean 13·4 ml/min; 8·3 to 18·5), 11 of the 34 showing no increase at all. In these 11 non-responders the mean systolic blood pressure was higher than that in the 23 others (178·5 mm Hg v 157 mm Hg, respectively). Mean urinary albumin excretion was abnormal in the patients (93·3 mg/24 h; 44·2 to 142·4); eight of the 11 non-responders had an albumin excretion above the normal range (>20 mg/24 h). In the 11 patients without renal functional reserve a positive correlation was found between basal creatinine clearance and albumin excretion (r=0·695).As consumed renal reserve and albuminuria are markers of glomerular hyperfiltration studying renal function before and after infusion of amino acids can detect hypertensive patients at risk of progressive renal damage.     

Plasma TSH and Serum T-4 Levels in Long-term Follow-up of Patients Treated with 131I for Thyrotoxicosis

In February 1972 58% of patients euthyroid after iodine-131 therapy given for thyrotoxicosis between 1954 and 1966 had a high plasma TSH (>7·4 μU/ml) and 42% a normal plasma TSH level. A group of 69 of the euthyroid patients with high plasma TSH levels (25·0±2·0 μU/ml) in 1972 were re-examined 15 and 24 months later. The mean plasma TSH in the 66 patients remaining euthyroid at 15 months was 22·6±1·8 μU/ml, while three patients had become hypothyroid. At 24 months 64 of the patients were still available for study, of whom 61 remained euthyroid with a mean plasma TSH of 21·6±2·0 μU/ml, and a further three had become hypothyroid.All of a group of 61 of the euthyroid patients with normal plasma TSH levels (4·0±0·2 μU/ml) in 1972 remained euthyroid at 24 months with a mean plasma TSH of 4·1±0·3 μU/ml, though the plasma TSH level had become slightly raised in three.The mean serum T-4 level in the euthyroid patients with a high plasma TSH was significantly lower, though still in the normal range, than that in the euthyroid patients with a normal plasma TSH both in 1972 and in 1974.Since no patient with a normal plasma TSH level after iodine-131 treatment six to 18 years earlier for thyrotoxicosis developed hypothyroidism over a two-year period, the follow-up of such patients need not be so rigorous as that of similarly treated euthyroid patients with raised plasma TSH levels in whom hypothyroidism developed at the rate of 5% per year.     

Beriberi heart disease in London

Haemodynamic measurements before and after treatment are described in two patients with beriberi heart disease. The first patient had severe disease with a cardiac output of 17·3 litres per minute, which had returned to normal a month later. The second patient had moderate disease with a cardiac output of 7·4 litres per minute; a fall in this and a rise in systemic vascular resistance was found one and two hours after the intravenous injection of aneurine hydrochloride. The plasma pyruvate concentration was raised in the first patient but only slightly so in the second, in whom the pyruvate metabolism test was abnormal. The haemodynamic studies in both cases were of considerable help in making the diagnosis. The diagnosis of beriberi should be considered in any patient with heart disease who has a history of alcoholism, especially as prompt vitamin treatment is curative.     

Team Work Load in an English General Practice—I

A survey of the total care provided by a general practitioner and his paramedical team for 3,137 patients in Teesside in 1972 showed that even in this area of high morbidity and mortality the work load was very small. The doctor held an average of 2·3 consultations per patient per year, and the overall average for the team of doctor, nurse, and health visitor was only 3·1. By delegating work to a team of trained paramedical workers, by increasing the proportion of personal medicine, and by engaging the co-operation of his patients, the general practitioner reduced his work load considerably, without any apparent reduction in standard of care.     

Meta-Analysis of Randomised Clinical Trials Comparing Idarubicin + Cytarabine with Daunorubicin + Cytarabine as the Induction Chemotherapy in Patients with Newly Diagnosed Acute Myeloid Leukaemia

Background

To determine whether the use of idarubicin+cytarabine (IA) is more effective than the use of daunorubicin+cytarabine (DA) as induction chemotherapy for patients with newly diagnosed acute myeloid leukaemia.

Methods

A computer-based search was performed. Randomised trials comparing IA with DA as induction therapy for newly diagnosed AML were included in this meta-analysis. The primary outcome of interest for our analysis was survival (disease-free survival, event-free survival and overall survival); the secondary endpoint was complete remission.

Results

Ten trials with 4,060 patients were eligible for this meta-analysis. Our pooled results suggest that IA is associated with a significant advantage in CR (RR = 1·23; 95% CI = 1·07–1·41, p = 0.004), EFS (HR = 0·64; 95% CI = 0·45–0·91, p = 0.013), and OS (HR = 0·88; 95% CI = 0·81–0·95, p = 0.02) but not in DFS (HR = 0·90; 95% CI = 0·80–1·00, p = 0.06). In the subgroup analysis, age had a significant interaction with OS and CR benefits.

Conclusion

Our analysis indicated that IA could improve the duration of overall survival compared to DA as induction therapy for young patients with newly diagnosed AML. Further study is needed to determine whether IA can produce clinical benefits in selected genetic or molecular subgroups of young AML patients.     

Electronegative Low-Density Lipoprotein Increases C-Reactive Protein Expression in Vascular Endothelial Cells through the LOX-1 Receptor

Objectives

Increased plasma C-reactive protein (CRP) levels are associated with the occurrence and severity of acute coronary syndrome. We investigated whether CRP can be generated in vascular endothelial cells (ECs) after exposure to the most electronegative subfraction of low-density lipoprotein (LDL), L5, which is atherogenic to ECs. Because L5 and CRP are both ligands for the lectin-like oxidized LDL receptor-1 (LOX-1), we also examined the role of LOX-1.

Methods and Results

Plasma LDL samples isolated from asymptomatic hypercholesterolemic (LDL cholesterol [LDL-C] levels, 154.6±20 mg/dL; n = 7) patients and normocholesterolemic (LDL-C levels, 86.1±21 mg/dL; P<0.001; n = 7) control individuals were chromatographically resolved into 5 subfractions, L1-L5. The L5 percentage (L5%) and the plasma L5 concentration ([L5]  =  L5% × LDL-C) in the patient and control groups were 8.1±2% vs. 2.3±1% (P<0.001) and 12.6±4 mg/dL vs. 1.9±1 mg/dL (P<0.001), respectively. In hypercholesterolemic patients treated with atorvastatin for 6 months (10 mg/day), [L5] decreased from 12.6±4 mg/dL to 4.5±1.1 mg/dL (P = 0.011; n = 5), whereas both [L5] and L5% returned to baseline levels in 2 noncompliant patients 3 months after discontinuation. In cultured human aortic ECs (HAECs), L5 upregulated CRP expression in a dose- and time-dependent manner up to 2.5-fold (P<0.01), whereas the least electronegative subfraction, L1, had no effect. DiI-labeled L1, internalized through the LDL receptor, became visible inside HAECs within 30 seconds. In contrast, DiI-labeled L5, internalized through LOX-1, became apparent after 5 minutes. L5-induced CRP expression manifested at 30 minutes and was attenuated by neutralizing LOX-1. After 30 minutes, L5 but not L1 induced reactive oxygen species (ROS) production. Both L5-induced ROS and CRP production were attenuated by ROS inhibitor N-acetyl cysteine.

Conclusions

Our results suggest that CRP, L5, and LOX-1 form a cyclic mechanism in atherogenesis and that reducing plasma L5 levels with atorvastatin disrupts the vascular toxicity of L5.     

Technetium-99m in the Diagnosis of Thyrotoxicosis

The thyroid uptake at 20 minutes of intravenously administered Technetium-99^m (^99mTc) was measured in 117 patients with a standard scintillation counter. Patients were divided into three groups on the basis of clinical assessment, four-hour ¹³¹I uptake, triiodothyronine (T-3) resin uptake, and protein-bound iodine measurements.In 31 patients with no evidence of thyroid disease the mean ^99m Tc uptake was 1·8% ±S.D. 1·1%. In 32 patients with thyroid enlargement who were euthyroid the mean uptake was 2·5% ±S.D. 2·2%. In 54 thyrotoxic patients the mean uptake was 17·7% with a range of 4·1 to 44%, all cases having an uptake above the upper limit of normal (4·0%). These results agree closely with reported uptake studies using scanning techniques. In seven patients the extrathyroidal neck activity was measured by using a scanner, and the mean was 6·3% of the extrathyroidal total body radioactivity comparing favourably with an assumed 6% used in our calculations.We have shown that the measurement of the thyroid uptake of ^99mTc with a scintillation counter is of value, and that it is not necessary to use scanning techniques in the diagnosis of thyrotoxicosis. Advantages of ^99m Tc are minimal radiation, reduction in patient and laboratory time, and low cost.     

Passive Flexion and Femoral Vein Flow: A Study Using a Motorized Foot Mover

The effect of rhythmic passive flexion of the foot on femoral vein blood volume flow rate has been investigated in 11 patients undergoing surgery for varicose veins. With rates of flexion varying from 24 to 50 per minute and with amplitudes varying from 20° to 50° it has been shown that the peak femoral vein flow can be increased to twice its normal value and that its pulsatility can be increased elevenfold. These increases are proportional to both the rate and the amplitude of the flexion, the maximum occurring, theoretically, when the foot is flexed ±28° about a line perpendicular to the leg.The investigation has further shown that the effects of sustained passive flexion are maintained, without appreciable dimunition, for 30 minutes and that the maximum increases are produced in those patients who have the lowest resting flows. It is suggested that per-operative passive flexion of the feet may be a good prophylactic against postoperative deep vein thrombosis.     

Impaired aerobic work capacity in insulin dependent diabetics with increased urinary albumin excretion

To assess whether decreased aerobic work capacity was associated with albuminuria in insulin dependent diabetics aerobic capacity was measured in three groups of 10 patients matched for age, sex, duration of diabetes, and degree of physical activity. Group 1 comprised 10 patients with normal urinary albumin excretion (<30 mg/24 h), group 2 comprised 10 with incipient diabetic nephropathy (urinary albumin excretion 30-300 mg/24 h, and group 3 comprised 10 with clinical diabetic nephropathy (urinary albumin excretion >300 mg/24 h). Ten non-diabetic subjects matched for sex, age, and physical activity served as controls. Oxygen uptake was similar in the four groups at rest and during a 75 W workload. Maximal oxygen uptake was also similar in the control subjects and group 1 (median 41·7, (range 29·1-53·0) ml/kg/min v 38·5 (26·6-59·2) ml/kg/min, respectively), but was significantly lower in group 2 (27·7 (13·9-44·3) ml/kg/min) and group 3 (26·8 (22·6-36·7) ml/kg/min). The difference in maximal oxygen uptake between groups 1 and 2 was 10·8 ml/kg/min (95% confidence interval 3·6 to 23·4 ml/kg/min) and between groups 1 and 3, 11·7 ml/kg/min (4·9 to 22·5 ml/kg/min). These differences were not explained by differences in metabolic control or the degree of autonomic neuropathy.Thus the insulin dependent diabetics with only slightly increased urinary albumin excretion had an appreciably impaired aerobic work capacity which could not be explained by autonomic neuropathy or the duration of diabetes. Whether the reduced capacity is due to widespread microangiopathy or another pathological process affecting the myocardium remains to be established.     

Twelve Weeks of Sprint Interval Training Improves Indices of Cardiometabolic Health Similar to Traditional Endurance Training despite a Five-Fold Lower Exercise Volume and Time Commitment

AimsWe investigated whether sprint interval training (SIT) was a time-efficient exercise strategy to improve insulin sensitivity and other indices of cardiometabolic health to the same extent as traditional moderate-intensity continuous training (MICT). SIT involved 1 minute of intense exercise within a 10-minute time commitment, whereas MICT involved 50 minutes of continuous exercise per session.MethodsSedentary men (27±8y; BMI = 26±6kg/m²) performed three weekly sessions of SIT (n = 9) or MICT (n = 10) for 12 weeks or served as non-training controls (n = 6). SIT involved 3x20-second ‘all-out’ cycle sprints (~500W) interspersed with 2 minutes of cycling at 50W, whereas MICT involved 45 minutes of continuous cycling at ~70% maximal heart rate (~110W). Both protocols involved a 2-minute warm-up and 3-minute cool-down at 50W.ResultsPeak oxygen uptake increased after training by 19% in both groups (SIT: 32±7 to 38±8; MICT: 34±6 to 40±8ml/kg/min; p<0.001 for both). Insulin sensitivity index (CS_I), determined by intravenous glucose tolerance tests performed before and 72 hours after training, increased similarly after SIT (4.9±2.5 to 7.5±4.7, p = 0.002) and MICT (5.0±3.3 to 6.7±5.0 x 10⁻⁴ min^-1 [μU/mL]^-1, p = 0.013) (p<0.05). Skeletal muscle mitochondrial content also increased similarly after SIT and MICT, as primarily reflected by the maximal activity of citrate synthase (CS; P<0.001). The corresponding changes in the control group were small for VO₂peak (p = 0.99), CS_I (p = 0.63) and CS (p = 0.97).ConclusionsTwelve weeks of brief intense interval exercise improved indices of cardiometabolic health to the same extent as traditional endurance training in sedentary men, despite a five-fold lower exercise volume and time commitment.