Basal and T₃-induced ROS production in lymphocyte mitochondria is increased in type 2 diabetic patients

Mitochondrial function, including production of reactive oxygen species (ROS), is important in the pathogenesis of diabetes and its complications. Thyroid hormones are major regulator of these processes. Hence, the aim of this study was to examine the thyroid hormone regulation of ROS production in human lymphocytes in patients with diabetes mellitus type 2 (T2DM). Lymphocytes from 10 controls and 10 persons with T2DM were examined. Mitochondrial membrane potential (MMP) was examined by flow cytometry after staining with MitoTracker Green (MTG). Similarly ROS was measured following staining with carboxy-H₂DCFDA. MMP was increased in T2DM patients and T₃ stimulation increased MMP in controls [1398 a.u. (979-4094) vs. 2156 a.u. (1611-15189), p=0.04, median and quartiles] as well as in T2DM patients [9167 a.u. (7387-11746) vs. 20274 a.u. (17183-27839 p=0.004, median and quartiles]. Basal ROS concentration was increased in lymphocytes from T2DM and T₃ significantly stimulated ROS concentration in controls [3691 a.u. (2584-6396) vs. 5650 a.u. (3001-7802) p=0.013, median and quartiles] and in T2DM patients [19271 a.u. (6288-25282) vs. 23178 a.u. (10004-28857) p=0.013, median and quartiles]. The ratio of ROS production related to MMP was significantly higher in T2DM, unstimulated as well as T₃-stimulated in T2DM. Unstimulated and T₃ stimulated ROS production and MMP were higher in lymphocytes from diabetic patients. An altered balance between ROS production and MMP, favoring ROS production in T2DM patients, was found suggesting that an increased mitochondrial sensitivity for T₃ may be a significant factor responsible for increased ROS activity in diabetic patients.

Insulin analogues in children with Type 1 diabetes: a 52-week randomized clinical trial

AIMS

This 52-week, randomized, multinational, open-label, parallel-group, non-inferiority trial investigated the efficacy and safety of basal-bolus treatment with insulin detemir vs. NPH (neutral protamine Hagedorn) insulin, in combination with insulin aspart, in subjects aged 2-16 years with Type 1 diabetes mellitus.

METHODS

Of the 347 randomized and exposed subjects, 177 received insulin detemir and 170 NPH insulin, both administered once or twice daily in combination with mealtime insulin aspart. Glycaemic measurements and weight were followed over 52 weeks.

RESULTS

After 52 weeks, insulin detemir was shown to be non-inferior to NPH insulin with regard to HbA(1c) [mean difference insulin detemir-NPH: 1.30 mmol/mol, 95% CI -1.32 to 3.92 (0.12%, 95% CI -0.12 to 0.36) in the full analysis set and 1.41 mmol/mol, 95% CI -1.26 to 4.08 (0.13%, 95% CI -0.12 to 0.37) in the per protocol analysis set]. Hypoglycaemic events per subject-year of exposure of 24-h and nocturnal hypoglycaemia were significantly lower with insulin detemir than with NPH insulin (rate ratio 0.76, 95% CI 0.60-0.97, P = 0.028 and 0.62, 95% CI 0.47-0.84, P = 0.002, respectively). Weight standard deviation (sd) scores (body weight standardized by age and gender) decreased with insulin detemir, but increased slightly with NPH insulin (change: -0.12 vs. 0.04, P < 0.001). At end of the trial, median insulin doses were similar in both treatment groups.

CONCLUSIONS

Insulin detemir was non-inferior to NPH insulin after 52 weeks' treatment of children and adolescents aged 2-16 years, and was associated with a significantly lower risk of hypoglycaemia, together with significantly lower weight sd score when compared with NPH insulin.

First detection of livestock-associated meticillin-resistant Staphylococcus aureus CC398 in bulk tank milk in the United Kingdom, January to July 2012

Livestock-associated meticillin-resistant Staphylococcus aureus belonging to clonal complex 398 (LA-MRSA CC398) is an important cause of zoonotic infections in several countries, but there is only a single published report of this lineage from the United Kingdom (UK). Here, we describe the isolation of LA-MRSA CC398 from bulk tank milk from five geographically dispersed farms in the UK. Our findings suggest that LA-MRSA CC398 is established in livestock in the UK. Awareness of the potential occupational risks and surveillance in other food-producing animal species should be promoted.

First detection of livestock-associated meticillin-resistant Staphylococcus aureus CC398 in bulk tank milk in the United Kingdom, January to July 2012

Livestock-associated meticillin-resistant Staphylococcus aureus belonging to clonal complex 398 (LA-MRSA CC398) is an important cause of zoonotic infections in several countries, but there is only a single published report of this lineage from the United Kingdom (UK). Here, we describe the isolation of LA-MRSA CC398 from bulk tank milk from five geographically dispersed farms in the UK. Our findings suggest that LA-MRSA CC398 is established in livestock in the UK. Awareness of the potential occupational risks and surveillance in other food-producing animal species should be promoted.

Measures of the recovery orientation of mental health services: systematic review

PURPOSE

The review aimed to (1) identify measures that assess the recovery orientation of services; (2) discuss how these measures have conceptualised recovery, and (3) characterise their psychometric properties.

METHODS

A systematic review was undertaken using seven sources. The conceptualisation of recovery within each measure was investigated by rating items against a conceptual framework of recovery comprising five recovery processes: connectedness; hope and optimism; identity; meaning and purpose; and empowerment. Psychometric properties of measures were evaluated using quality criteria.

RESULTS

Thirteen recovery orientation measures were identified, of which six met eligibility criteria. No measure was a good fit with the conceptual framework. No measure had undergone extensive psychometric testing and none had data on test-retest reliability or sensitivity to change.

CONCLUSIONS

Many measures have been developed to assess the recovery orientation of services. Comparisons between the measures were hampered by the different conceptualisations of recovery used and by the lack of uniformity on the level of organisation at which services were assessed. This situation makes it a challenge for services and researchers to make an informed choice on which measure to use. Further work is needed to produce measures with a transparent conceptual underpinning and demonstrated psychometric properties.

Epidemiology of methicillin-resistant Staphylococcus aureus carrying the novel mecC gene in Denmark corroborates a zoonotic reservoir with transmission to humans

Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of healthcare-associated (HA), community-associated (CA) and livestock-associated (LA) infections. Recently, the discovery of human and bovine MRSA isolates carrying a new mecA gene homologue, mecA(LGA251) (now designated mecC), has caused concern because they are not detected by conventional, confirmatory tests for MRSA. Very little is known about their frequency, epidemiology and possible transmission between livestock and humans. In this study, the epidemiology of the mecC isolates in Denmark was investigated by screening the national collections of MRSA cases (from 1988 onwards) and S. aureus bacteraemia cases (from 1958 onwards). Isolates carrying mecC were only recovered infrequently before 2003 (n = 2) but now seem to be increasing, with 110 cases in 2003-2011. Clinical data on mecC-carrying MRSA demonstrated that mecC-MRSA were primarily community-acquired (CA-MRSA) and affected persons typically living in rural areas, being older than other CA-MRSA patients. Among 22 cases in Region Zealand, four reported contact with cattle and sheep. Two of these persons lived on farms with livestock positive for mecC-carrying MRSA, sharing spa type (t843), MLVA (MT429) and PFGE pattern with the human isolates. These observations indicate that mecC-carrying MRSA can be exchanged between humans and ruminants.

Analysis of reserve capacity and subsequent stenting in a case of subacute occlusion of the internal carotid artery

Introduction

While acute internal carotid artery (ICA) occlusions are increasingly being treated with carotid angioplasty and stenting (CAS), the utility of CAS in subacute stages is unclear.

Case Report

A 65-year-old patient with an acute left ICA occlusion and pre-existing occlusion on the right side presented with dysarthria and central right-sided facial palsy. Carbon dioxide (CO₂) reactivity within the left hemisphere was markedly reduced. Due to acute deterioration despite maximal conservative therapy CAS was performed 8 days after the initial event with an excellent result and symptoms subsided.

Conclusion

CAS in subacute ICA occlusion is possible. Patients should be selected carefully. Assessment of cerebrovascular CO₂ reactivity might provide valuable information.

Evidence of mitochondrial dysfunction in obese adolescents

AIM

Although obesity and weight gain generally are anticipated to be caused by an imbalance between energy intake and energy expenditure, the significance of thyroid hormones (TH) remains unclear. Examination of mitochondrial function may reflect intracellular thyroid hormone effect and elucidate whether a lower metabolic rate is present.

METHODS

In a group of 34 obese adolescents (age <16 years and body mass index above the age-related 95th percentile), and an age- and gender-matched group of 32 lean adolescent, thyroid stimulating hormone (TSH) and basal oxygen consumption were measured and mitochondrial function in peripheral blood monocytes was determined by flow cytometry.

RESULTS

Significant increase in TSH (3.06 +/- 1.56 mU/L vs. 2.33 +/- 0.91 mU/L, p < 0.05) and a decrease in VO2 (129 +/- 16 mL O2/m(2)*min vs. 146 +/- 15 mL O2/m(2)*min, p < 0.05) were observed in obese adolescents compared with lean adolescents. Flow cytometry analysis demonstrated a lower mitochondrial mass (6385 +/- 1962 a.u. vs. 7608 +/- 2328 a.u., p < 0.05) and mitochondrial membrane potential (11426 +/- 3861 a.u. vs. 14017 +/- 5536 a.u., p < 0.05) in obese adolescents compared with lean adolescents. These results are even more pronounced in adolescents with obese mothers.

CONCLUSION

In obese adolescents, the increased TSH and lowered VO2 propose a lowered basal metabolic rate and the impaired mitochondrial function suggests a decreased thyroid hormone stimulation of mitochondrial energy production. The maternal in-heritage is suggestive of a basal metabolic defect or mitochondrial resistance for TH.

Subclinical hypothyroidism affects mitochondrial function

The aim of the present study was to examine mitochondrial function in cells from persons with subclinical hypothyroidism and euthyroid controls. The participating persons were examined clinically and had basal oxygen consumption (VO(2)) determined. The concentrations of thyroid hormones and thyrotropine stimulating hormone were determined, and mitochondrial function in isolated mononuclear blood cells was examined by enzymatic methods [citrate synthase activity (CS)] and by flow cytometry (mitochondrial membrane potential by TMRM fluorescence and mitochondrial mass by MTG fluorescence). The ratio of T(4)/T(3) was lowered in subclinical hypothyroidism patients compared to controls (2.5+/-0.5 vs. 2.9+/-0.4, p=0.005). VO(2) was increased in persons with subclinical hypothyroidism compared to controls (adolescents: 134+/-27 ml O(2)/min*m(2) vs. 119+/-27 ml O(2)/min*m(2), p=0.006, adults: 139+/-14 ml O(2)/min*m(2) vs. 121+/-17 ml O(2)/min*m(2), p=0.001). The mitochondrial function, represented by citrate synthase activity, MTG, and TMRM fluorescence were all increased (CS in subclinical hypothyroidism vs. controls: 0.074+/-0.044 nmol/mg*min vs. 0.056+/-0.021 nmol/mg*min, p=0.005; MTG fluorescence in subclinical hypothyroidism vs. controls: 7,482+/-1,733 a.u. vs. 6,391+/-2,171 a.u., p=0.027; TMRM fluorescence in subclinical hypothyroidism vs. controls: 13,449+/-3,807 a.u. vs. 11,733+/-4,473 a.u, p=0.04). Our results indicate an increased mitochondrial stimulation, eventually caused by increased deiodination of T(4) to intracellular bioactive iodothyronines in adults and adolescents with subclinical hypothyroidism.