Treatment and prevention of Mycobacterium ulcerans infection (Buruli ulcer) in Australia: guideline update

• Guidelines reflecting contemporary clinical practice in the management of Buruli ulcer (Mycobacterium ulcerans infection) in Australia were published in 2007.

• Management has continued to evolve, as new evidence has become available from randomised trials, case series and increasing clinical experience with oral antibiotic therapy.

• Therefore, guidelines on the diagnosis, treatment and prevention of Buruli ulcer in Australia have been updated. They include guidance on the new role of antibiotics as first-line therapy; the shortened duration of antibiotic treatment and the use of all-oral antibiotic regimens; the continued importance, timing and role of surgery; the recognition and management of paradoxical reactions during antibiotic treatment; and updates on the prevention of disease.

The catheter to vein ratio and rates of symptomatic venous thromboembolism in patients with a peripherally inserted central catheter (PICC): a prospective cohort study.

BACKGROUND: Peripherally inserted central catheters (PICCs) are a common vascular access device used in clinical practice. Their use may be complicated by adverse events such as venous thromboembolism (VTE). The size of the vein used for PICC insertion and thus the catheter to vein ratio is thought to be a controllable factor in the reduction of VTE rates in patients who have a PICC. However, an optimal catheter to vein ratio for PICC insertion has not previously been investigated to inform clinical practice. OBJECTIVES: To determine the effect of the catheter to vein ratio (proportion of the vein measured at the insertion point taken up by the catheter) on rates of symptomatic VTE in patients with a PICC and identify the optimal ratio cut-off point to reduce rates of this adverse event. METHOD: Adult patients waiting for PICC insertion at a large metropolitan teaching hospital were recruited between May and December 2013. Vein diameter at the PICC insertion site was measured using ultrasound with in-built callipers. Participants were followed up at eight weeks to determine if they developed symptomatic VTE. RESULTS: Data were available for 136 patients (50% cancer; 44% infection; 6% other indication for PICC). Mean age was 57 years with 54% males. There were four cases of confirmed symptomatic VTE (two involving the deep veins, one peripheral vein and one pulmonary embolism). Receiver operator characteristic (ROC) analysis determined that a 45% catheter to vein ratio was the ideal cut off point to maximise sensitivity and specificity (AUC 0.761; 95% CI 0.681-0.830). When a ratio of 46% or above was compared to one that was less than or equal to 45% using a log binomial generalised linear model it was found that participants with a catheter to vein ratio >45% were 13 times more likely to suffer VTE (relative risk 13, p=0.022; CI 1.445-122.788). CONCLUSION: It was found that a 45% catheter to vein ratio was the optimal cut off with high sensitivity and specificity to reduce the risk of VTE. However, further research is needed to confirm these results as although adequately powered; the number of cases of VTE was comparatively small, resulting in wide confidence intervals.

An Australian experience of managing pressure ulcers in persons with SCI

Pressure ulcers are a difficult and complex problem, frequently resulting in poor patient outcomes ,and significantly increased cost of care. This project evolved from a desire to improve the management and subsequent outcomes for persons with spinal cord injury (SCI) who experience pressure ulcers acquired in the community. The vast body of work related to pressure ulcers has focused on risk assessment and prevention. However, there has been little interest in the management of prevailing pressure ulcers. Using a retrospective case history audit and interviews with patients and health care workers from an Australian spinal services unit, current practices associated with the care of pressure ulcers are described. A number of issues are identified that relate to funding, diet, attitudes, consistency of care, and low levels of staff interest in pressure ulcer management. This work provides baseline data from which current management practices can be reviewed, revised, and empirically evaluated.

Treatment with supplementary arginine, vitamin C and zinc in patients with pressure ulcers: A randomised controlled trial

Background & Aims
Nutrients putatively implicated in pressure ulcer healing were evaluated in a clinical setting.

Methods
Sixteen inpatients with a stage 2, 3 or 4 pressure ulcer randomised to receive daily a standard hospital diet; a standard diet plus two high-protein/energy supplements; or a standard diet plus two high-protein/energy supplements containing additional arginine (9 g), vitamin C (500 mg) and zinc (30 mg). Nutritional status measurements (dietary, anthropometric and biochemical) and pressure ulcer size and severity (by PUSH tool; Pressure Ulcer Scale for Healing; 0=completely healed, 17=greatest severity) were measured weekly for 3 weeks.

Results
Patients’ age and BMI ranges were 37–92 years and 16.4–28.1 kg/m2, respectively. Baseline PUSH scores were similar between groups (8.7±0.5). Only patients receiving additional arginine, vitamin C and zinc demonstrated a clinically significant improvement in pressure ulcer healing (9.4±1.2 vs. 2.6±0.6; baseline and week 3, respectively; P<0.01). All patient groups presented with low serum albumin and zinc and elevated C-reactive protein. There were no significant changes in biochemical markers, oral dietary intake or weight in any group.

Conclusions
In this small set of patients, supplementary arginine, vitamin C and zinc significantly improved the rate of pressure ulcer healing. The results need to be confirmed in a larger study.

Role of the ATP-binding cassette drug transporters in the intestinal absorption of tanshinone IIB, one of the major active diterpenoids from the root of Salvia miltiorrhiza

There is an increasing use of herbal medicines worldwide, and the extracts from the root of Salvia miltiorrhiza are widely used in the treatment of angina and stroke. In this study, we investigated the mechanism for the intestinal absorption of tanshinone IIB (TSB), a major constituent of S. miltiorrhiza. The oral bioavailability of TSB was about 3% in rats with less proportional increase in its maximum plasma concentration (C_max) and area under the plasma concentration-time curve (AUC) with increasing dosage. The time to C_max (T_max) was prolonged at higher oral dosage. In a single pass rat intestinal perfusion model, the permeability coefficients (P_app) based on TSB disappearance from the lumen (P_lumen) were 6.2- to 7.2-fold higher (p < 0.01) than those based on drug appearance in mesenteric venous blood (P_blood). The uptake and efflux of TSB in Caco-2 cells were also significantly altered in the presence of an inhibitor for P-glycoprotein (PgP) or for multi-drug resistance associated protein (MRP1/2). TSB transport from the apical (AP) to basolateral (BL) side in Caco-2 monolayers was 3.3- to 5.7-fold lower than that from BL to AP side, but this polarized transport was attenuated by co-incubation of PgP or MRP1/2 inhibitors. The P_app values of TSB in the BL-AP direction were significantly higher in MDCKII cells over-expressing MDR1 or MRP1, but not in cells over-expressing MRP2-5, as compared with the wild-type cells. The plasma AUC_0-24hr in mdr1a and mrp1 gene-deficient mice was 10.2- to 1.7-fold higher than that in the wild-type mice. Furthermore, TSB significantly inhibited the uptake of digoxin and vinblastine in membrane vesicles containing PgP or MRP1. TSB also moderately stimulated PgP ATPase activity. Taken collectively, our findings indicate that TSB is a substrate for PgP and MRP1 and that drug resistance to TSB therapy and drug interactions may occur through PgP and MRP1 modulation.

Effects of dietary fat and conjugated linoleic acid on plasma metabolite concentrations and metabolic responses to homeostatic signals in pigs

Sixteen female cross-bred (Large White × Landrace) pigs (initial weight 65 kg) with venous catheters were randomly allocated to four treatment groups in a 2×2 factorial design. The respective factors were dietary fat (25 or 100 g/kg) and dietary conjugated linoleic acid (CLA; 0 or 10 g CLA-55/kg). Pigs were fed every 3 h (close to ad libitum digestible energy intake) for 8 d and were bled frequently. Plasma glucose and non-esterified fatty acid (NEFA) responses to insulin and adrenaline challenges were determined on day 8. Plasma concentrations of NEFA were significantly increased (10·5 and 5·4 % for low- and high-fat diets respectively, P=0·015) throughout the experiment, suggesting that there was a possible increase in fat mobilisation. The increase in lipolysis, an indicator of ß-adrenergic stimulated lipolysis, was also evident in the NEFA response to adrenaline. However, the increase in plasma triacylglycerol (11·0 and 7·1 % for low- and high-fat diets respectively, P=0·008) indicated that CLA could have reduced fat accretion via decreased adipose tissue triacylglycerol synthesis from preformed fatty acids, possibly through reduced lipoprotein lipase activity. Plasma glucose, the primary substrate for de novo lipid synthesis, and plasma insulin levels were unaffected by dietary CLA suggesting that de novo lipid synthesis was largely unaffected (P=0·24 and P=0·30 respectively). In addition, the dietary CLA had no effect upon the ability of insulin to stimulate glucose removal.

Effect of sodium bicarbonate on muscle metabolism during intense endurance cycling

Introduction: Sodium bicarbonate (NaHCO₃) ingestion has been shown to increase both muscle glycogenolysis and glycolysis during brief submaximal exercise. These changes may be detrimental to performance during more prolonged, exhaustive exercise. This study examined the effect of NaHCO₃ ingestion on muscle metabolism and performance during intense endurance exercise of ~60 min in seven endurance-trained men. Methods: Subjects ingested 0.3 g·kg^-1 body mass of either NaHCO₃ or CaCO₃ (CON) 2 h before performing 30 min of cycling exercise at 77 ± 1% [latin capital V with dot above]O_2peak followed by completion of 469 ± 21 kJ as quickly as possible (~30 min, ~80% [latin capital V with dot above]O_2peak). Results: Immediately before, and throughout exercise, arterialized-venous plasma HCO₃- concentrations were higher (P < 0.05) whereas plasma and muscle H⁺ concentrations were lower (P < 0.05) in NaHCO₃ compared with CON. Blood lactate concentrations were higher (P < 0.05) during exercise in NaHCO₃, but there was no difference between trials in muscle glycogen utilization or muscle lactate content during exercise. Reductions in PCr and ATP and increases in muscle Cr during exercise were also unaffected by NaHCO₃ ingestion. Accordingly, exercise performance time was not different between treatments. Conclusion: NaHCO₃ ingestion resulted in a small muscle alkalosis but had no effect on muscle metabolism or intense endurance exercise performance in well-trained men.

The influence of allopurinol on urinary purine loss after repeated sprint exercise in man

The influence of allopurinol on urinary purine loss was examined in 7 active male subjects (age 24.9 ± 3.0 years, weight 82.8 ± 8.3 kg, V˙o₂peak 48.1 ± 6.9 mL · kg⁻¹ · min⁻¹). These subjects performed, in random order, a trial with 5 days of prior ingestion of a placebo or allopurinol. Each trial consisted of eight 10-second sprints on an air-braked cycle ergometer and was separated by at least a week. A rest period of 50 seconds separated each repeated sprint. Forearm venous plasma inosine, hypoxanthine (Hx) and uric acid concentrations were measured at rest and during 120 minutes of recovery from exercise. Urinary inosine, Hx, xanthine, and uric acid excretion were also measured before and for 24 hours after exercise. During the first 120 minutes of recovery, plasma Hx concentrations, as well as the urinary Hx and xanthine excretion rates, were higher (P < .05) with allopurinol compared with the placebo trial. In contrast, plasma uric acid concentration and urinary uric acid excretion rates were lower (P < .05) with allopurinol. The total urinary excretion of purines (inosine + Hx + xanthine + uric acid) above basal levels was higher in the allopurinol trial compared with placebo. These results indicate that the total urinary purine excretion after intermittent sprint exercise was enhanced with allopurinol treatment. Furthermore, the composition of urinary purines was markedly affected by this drug.

Regulation of HSL serine phosphorylation in skeletal muscle and adipose tissue

Hormone-sensitive lipase (HSL) is important for the degradation of triacylglycerol in adipose and muscle tissue, but the tissue-specific regulation of this enzyme is not fully understood. We investigated the effects of adrenergic stimulation and AMPK activation in vitro and in circumstances where AMPK activity and catecholamines are physiologically elevated in humans in vivo (during physical exercise) on HSL activity and phosphorylation at Ser⁵⁶³ and Ser⁶⁶⁰, the PKA regulatory sites, and Ser⁵⁶⁵, the AMPK regulatory site. In human experiments, skeletal muscle, subcutaneous adipose and venous blood samples were obtained before, at 15 and 90 min during, and 120 min after exercise. Skeletal muscle HSL activity was increased by ~80% at 15 min compared with rest and returned to resting rates at the cessation of and 120 min after exercise. Consistent with changes in plasma epinephrine, skeletal muscle HSL Ser⁵⁶³ and Ser⁶⁶⁰ phosphorylation were increased by 27% at 15 min (P < 0.05), remained elevated at 90 min, and returned to preexercise values postexercise. Skeletal muscle HSL Ser⁵⁶⁵ phosphorylation and AMPK signaling were increased at 90 min during, and after, exercise. Phosphorylation of adipose tissue HSL paralleled changes in skeletal muscle in vivo, except HSL Ser⁶⁶⁰ was elevated 80% in adipose compared with 35% in skeletal muscle during exercise. Studies in L6 myotubes and 3T3-L1 adipocytes revealed important tissue differences in the regulation of HSL. AMPK inhibited epinephrine-induced HSL activity in L6 myotubes and was associated with reduced HSL Ser660 but not Ser563 phosphorylation. HSL activity was reduced in L6 myotubes expressing constitutively active AMPK, confirming the inhibitory effects of AMPK on HSL activity. Conversely, in 3T3-L1 adipocytes, AMPK activation after epinephrine stimulation did not prevent HSL activity or glycerol release, which coincided with maintenance of HSL Ser660 phosphorylation. Taken together, these data indicate that HSL activity is maintained in the face of AMPK activation as a result of elevated HSL Ser660 phosphorylation in adipose tissue but not skeletal muscle.

Splanchnic blood flow and hepatic glucose production in exercising humans : role of renin-angiotensin system

The study examined the implication of the renin-angiotensin system (RAS) in regulation of splanchnic blood flow and glucose production in exercising humans. Subjects cycled for 40 min at 50% maximal O2 consumption (VO2 max) followed by 30 min at 70% VO2 max either with [angiotensin-converting enzyme (ACE) blockade] or without (control) administration of the ACE inhibitor enalapril (10 mg iv). Splanchnic blood flow was estimated by indocyanine green, and splanchnic substrate exchange was determined by the arteriohepatic venous difference. Exercise led to an ~20-fold increase (P < 0.001) in ANG II levels in the control group (5.4 ± 1.0 to 102.0 ± 25.1 pg/ml), whereas this response was blunted during ACE blockade (8.1 ± 1.2 to 13.2 ± 2.4 pg/ml) and in response to an orthostatic challenge performed postexercise. Apart from lactate and cortisol, which were higher in the ACE-blockade group vs. the control group, hormones, metabolites, VO2, and RER followed the same pattern of changes in ACE-blockade and control groups during exercise. Splanchnic blood flow (at rest: 1.67 ± 0.12, ACE blockade; 1.59 ± 0.18 l/min, control) decreased during moderate exercise (0.78 ± 0.07, ACE blockade; 0.74 ± 0.14 l/min, control), whereas splanchnic glucose production (at rest: 0.50 ± 0.06, ACE blockade; 0.68 ± 0.10 mmol/min, control) increased during moderate exercise (1.97 ± 0.29, ACE blockade; 1.91 ± 0.41 mmol/min, control). Refuting a major role of the RAS for these responses, no differences in the pattern of change of splanchnic blood flow and splanchnic glucose production were observed during ACE blockade compared with controls. This study demonstrates that the normal increase in ANG II levels observed during prolonged exercise in humans does not play a major role in the regulation of splanchnic blood flow and glucose production.

A mechanistic study of the intestinal absorption of crypotanshinone, the major active constituent of Saliva miltiorrhiza

The nature of intestinal absorption of most herbal medicine is unknown. Cryptotanshinone (CTS) is the principal active constituent of the widely used cardiovascular herb Salvia miltiorrhiza (Danshen). We investigated the oral bioavailability of CTS in rats and the mechanism for its intestinal absorption using several in vitro and in vivo models:1) Caco-2 cell monolayers; 2) monolayers of MDCKII cells overexpressing P-glycoprotein
(PgP); and 3) single-pass rat intestinal perfusion with mesenteric vein cannulation. The systemic bioavailabilities of CTS after oral and intraperitoneal administration at 100 mg/kg were 2.05 and 10.60%, respectively. In the perfused rat intestinal model, permeability coefficients based on CTS disappearance from the luminal perfusate (P_lumen) were 6.7- to 10.3-fold higher than permeability coefficients based on drug appearance in venous blood (P_blood). P_blood significantly increased in the presence of the P-gP inhibitor, verapamil. CTS transport across Caco-2 monolayers was pH-, temperature- and ATP-dependent. The transport from the apical (AP) to the basolateral (BL) side was 3- to 9-fold lower than that from the BL to the AP side. Inclusion of verapamil (50 µM) in both AP and BL sides abolished the polarized CTS transport across Caco-2 cells. Moreover, CTS was significantly more permeable in the BL to AP than in the AP to BL direction in MDCKII and MDR1-MDCKII cells. The permeability coefficients in the BL to AP direction were significantly higher in MDCKII cells overexpressing PgP. These findings indicate that CTS is a substrate for PgP that can pump CTS into the luminal side.

Adiponectin in umbillcal cord blood is inversely related to low-density lipoprotein cholesteril but not ethnicity

Context: Adiponectin is a recognized protective risk marker for cardiovascular disease in adults and is associated with an optimal lipid profile. The role of adiponectin at birth is not well understood, and its relationship with the neonatal lipid profile is unknown. Because ethnic disparities in cardiovascular risk have been attributed to low adiponectin and its associated low high-density lipoprotein cholesterol (HDL-C), investigation at birth may help determine the etiology of these risk patterns.

Objective: Our objective was to investigate the relationship between neonatal adiponectin and lipid profile at birth in two ethnic groups in cord blood.

Design, Setting, and Participants: Seventy-four healthy mothers and their newborns of South Asian and White European origin were studied in this cross-sectional study at St. Mary’s Hospital, Manchester, United Kingdom.

Main Outcome Measures: Serum adiponectin, total cholesterol, HDL-C, low-density lipoprotein cholesterol (LDL-C), and triglyceride levels were measured in umbilical venous blood at birth and in maternal blood collected at 28 wk gestation.

Results: Cord adiponectin was significantly inversely associated with cord LDL-C (r = –0.32; P = 0.005) but not HDL-C. In a multiple regression analysis, cord LDL-C remained the most significant association of cord adiponectin (ß = –0.13; P < 0.001). We did not find any significant ethnic differences in cord adiponectin or lipids with the exception of triglycerides, which were significantly lower in South Asian newborns (P < 0.05).

Conclusion: This is the first report of an inverse relationship between cord adiponectin and LDL-C at birth. In contrast to adult studies, we found no significant association between adiponectin and HDL-C in cord blood. Our results and the strong independent association between adiponectin and HDL-C observed in adult studies suggest a role for adiponectin in lipid metabolism. Ethnic differences in adiponectin may arise after birth.

The fine line between harm reduction and harm production - development of a clinical policy on femoral (groin) injecting

The femoral region ('groin') appears to be increasingly commonly used by injecting drug users in the UK. With the advent of Britain's first supervised prescribed injectable opioid treatment clinic, unprecedented decisions and judgements were required about the safe supervision of this practice, or whether to permit this behaviour on site at all. This paper reports the reasons for, and outcome of, development of a clinical policy on injecting into the deep femoral vein (groin injecting)

Nutrition therapy in the prevention and treatment of pressure ulcers

Pressure ulcers are serious problems within hospital and aged care settings and are associated with adverse health outcomes and high treatment costs. Because of a high incidence of pressure ulcers in the health system, attention is now being directed to not just preventing, but also more effectively treating them. Nutrition plays a fundamental part in wound healing, with malnutrition, dehydration and recent weight loss identified as independent risk factors for the development of pressure ulcers. While the optimal nutrient intake to promote wound healing is unknown, increased needs for energy, protein, zinc and vitamins A, C and E have been documented. There is reasonable evidence to show that nutritional support, mostly by high-protein oral nutritional supplements, is effective in significantly reducing the incidence of pressure ulcers in at-risk patients by 25%. Intervention studies using high-protein or specialised disease-specific nutritional supplements support a trend to increased healing of established pressure ulcers. Such specialised supplements are typically based on defined amounts of arginine, vitamin C and zinc. Mechanisms by which nutritional support can aid in pressure ulcer prevention and healing are likely related to addressing macro- and/or micro-nutrient deficiencies arising from either poor oral intake or increased nutrient requirements related to the wound healing process. With much more research still to be done in this area, nutrition support appears an efficacious and costeffective adjunct to current medical and nursing approaches in the prevention and treatment of pressure ulcers.

An evidence-based practice approach to improving nursing care of acute stroke in an Australian emergency department

Aims. The aim of this study was to improve the emergency nursing care of acute stroke by enhancing the use of evidence regarding prevention of early complications.
Background. Preventing complications in the first 24–48 hours decreases stroke-related mortality. Many patients spend considerable part of the first 24 hours following stroke in the Emergency Department therefore emergency nurses play a key role in patient outcomes following stroke.
Design. A pre-test/post-test design was used and the study intervention was a guideline for Emergency Department nursing management of acute stroke.
Methods. The following outcomes were measured before and after guideline implementation: triage category, waiting time, Emergency Department length of stay, time to specialist assessment, assessment and monitoring of vital signs, temperature and blood glucose and venous-thromboembolism and pressure injury risk assessment and interventions.
Results. There was significant improvement in triage decisions (21Æ4% increase in triage category 2, p = 0Æ009; 15Æ6% decrease in triage category 4, p = 0Æ048). Frequency of assessments of respiratory rate (p = 0Æ009), heart rate (p = 0Æ022), blood pressure (p = 0Æ032) and oxygen saturation (p = 0Æ001) increased. In terms of risk management, documentation of pressure area
interventions increased by 28Æ8% (p = 0Æ006), documentation of nil orally status increased by 13Æ8% (ns), swallow assessment prior to oral intake increased by 41Æ3% (p = 0Æ003), speech pathology assessment in Emergency Department increased by 6Æ1% (ns) and there was 93Æ5 minute decrease in time to speech pathology assessment for admitted patients (ns).
Relevance to clinical practice. An evidence-based guideline can improve emergency nursing care of acute stroke and optimise patient outcomes following stroke. As the continuum of stroke care begins in the Emergency Department, detailed recommendations for evidence-based emergency nursing care should be included in all multidisciplinary guidelines for the management of acute stroke.