Nontuberculous mycobacteria in gastrostomy fed patients with cystic fibrosis

Multi-drug resistant Mycobacterium abscessus complex (MABSC) is a form of Nontuberculous mycobacteria (NTM) of special, international concern in Cystic Fibrosis (CF). We hypothesised that gastric juice and percutaneous endoscopic gastrostomy (PEG) feeding devices might yield MABSC isolates. Gastric juice and sputa from sixteen adult PEG fed CF patients and five replaced PEG tubes were studied. Bacterial and fungal isolates were cultured. Mycobacterium were identified by rpoB, sodA and hsp65 gene sequencing and strain typed using variable number tandem repeat. Bacteria and/or fungi grew from all gastric juice, sputa and PEG samples. MABSC were detected in 7 patients. Five had MABSC in their sputum. Two had an identical MABSC strain in their sputum and gastric juice and one had the same strain isolated from their PEG tube and sputum. Two patients who were sputum sample negative had MABSC isolated in their gastric juice or PEG tube. MABSC were therefore identified for the first time from a gastric sample in a minority of patients. We conclude that gastric juice and PEG-tubes may be a potential source of MABSC isolates in CF patients, and these findings warrant further study.

A Review of Current Regenerative Medicine Strategies that Utilize Nanotechnology to Treat Cartilage Damage

BACKGROUND

Cartilage is an important tissue found in a variety of anatomical locations. Damage to cartilage is particularly detrimental, owing to its intrinsically poor healing capacity. Current reconstructive options for cartilage repair are limited, and alternative approaches are required. Biomaterial science and Tissue engineering are multidisciplinary areas of research that integrate biological and engineering principles for the purpose of restoring premorbid tissue function. Biomaterial science traditionally focuses on the replacement of diseased or damaged tissue with implants. Conversely, tissue engineering utilizes porous biomimetic scaffolds, containing cells and bioactive molecules, to regenerate functional tissue. However, both paradigms feature several disadvantages. Faced with the increasing clinical burden of cartilage defects, attention has shifted towards the incorporation of Nanotechnology into these areas of regenerative medicine.

METHODS

Searches were conducted on Pubmed using the terms "cartilage", "reconstruction", "nanotechnology", "nanomaterials", "tissue engineering" and "biomaterials". Abstracts were examined to identify articles of relevance, and further papers were obtained from the citations within.

RESULTS

The content of 96 articles was ultimately reviewed. The literature yielded no studies that have progressed beyond in vitro and in vivo experimentation. Several limitations to the use of nanomaterials to reconstruct damaged cartilage were identified in both the tissue engineering and biomaterial fields.

CONCLUSION

Nanomaterials have unique physicochemical properties that interact with biological systems in novel ways, potentially opening new avenues for the advancement of constructs used to repair cartilage. However, research into these technologies is in its infancy, and clinical translation remains elusive.

An Update into the Application of Nanotechnology in Bone Healing

BACKGROUND

Bone differs from other organs in that it can regenerate and remodel without scar formation. There are instances of trauma, congenital bone disorder, bone disease and bone cancer where this is not possible. Without bone grafts and implants, deformity and disability would result. Human bone grafts are limited in their management of large or non-union fractures. In response, synthetic bone grafts and implants are available to the Orthopaedic Surgeon. Unfortunately these also have their limitations and associated complications. Nanotechnology involves the research, design and manufacture of materials with a grain size less than 100nm. Nano-phase materials follow the laws of quantum physics, not classical mechanics, resulting in novel behavioural differences compared to conventional counterparts.

METHODS

Past, present and future nanotechnology in bone healing literature is reviewed and discussed. The article highlights concepts which are likely to be instrumental to the future of nanotechnology in bone healing.

RESULTS

Nanotechnology in bone healing is an emerging field within Orthopaedic Surgery. There is a requirement for bone healing technologies which are biochemically and structurally similar to bone. Nanotechnology is a potential solution as the arrangement of bone includes nanoscopic collagen fibres and hydroxyapatite. This review centers on the novel field of nanotechnology in bone healing with discussion focusing on advances in bone grafts, implants, diagnostics and drug delivery.

CONCLUSION

The concept of nanotechnology was first introduced in 1959. Current nanoproducts for bone healing include nano-HA-paste-ostim and nano-beta-tricalcium phosphate-Vitoss. Nanophase technologies are considered to be superior bone healing solutions. Limited safety data and issues regarding cost and mass scale production require further research into this exciting field.

Involvement of cell surface TG2 in the aggregation of K562 cells triggered by gluten

Gluten-induced aggregation of K562 cells represents an in vitro model reproducing the early steps occurring in the small bowel of celiac patients exposed to gliadin. Despite the clear involvement of TG2 in the activation of the antigen-presenting cells, it is not yet clear in which compartment it occurs. Herein we study the calcium-dependent aggregation of these cells, using either cell-permeable or cell-impermeable TG2 inhibitors. Gluten induces efficient aggregation when calcium is absent in the extracellular environment, while TG2 inhibitors do not restore the full aggregating potential of gluten in the presence of calcium. These findings suggest that TG2 activity is not essential in the cellular aggregation mechanism. We demonstrate that gluten contacts the cells and provokes their aggregation through a mechanism involving the A-gliadin peptide 31-43. This peptide also activates the cell surface associated extracellular TG2 in the absence of calcium. Using a bioinformatics approach, we identify the possible docking sites of this peptide on the open and closed TG2 structures. Peptide docks with the closed TG2 structure near to the GTP/GDP site, by establishing molecular interactions with the same amino acids involved in stabilization of GTP binding. We suggest that it may occur through the displacement of GTP, switching the TG2 structure from the closed to the active open conformation. Furthermore, docking analysis shows peptide binding with the β-sandwich domain of the closed TG2 structure, suggesting that this region could be responsible for the different aggregating effects of gluten shown in the presence or absence of calcium. We deduce from these data a possible mechanism of action by which gluten makes contact with the cell surface, which could have possible implications in the celiac disease onset.

Reducing falls among older people in general practice: The ProAct65+ exercise intervention trial

BACKGROUND

Falls are common in the older UK population and associated costs to the NHS are high. Systematic reviews suggest that home exercise and group-based exercise interventions, which focus on progressively challenging balance and increasing strength, can reduce up to 42% of falls in those with a history of falls. The evidence is less clear for those older adults who are currently at low risk of falls.

AIM

ProAct65+, a large, cluster-randomised, controlled trial, investigated the effectiveness of a home exercise programme (Otago Exercise Programme (OEP)) and a group-based exercise programme (Falls Management Exercise (FaME)) compared to usual care (UC) at increasing moderate to vigorous physical activity (MVPA). This paper examines the trial's secondary outcomes; the effectiveness of the interventions at reducing falls and falls-related injuries.

SETTING & PARTICIPANTS

1256 community-dwelling older adults (aged 65+) were recruited through GP practices in two sites (London and Nottingham). Frequent fallers (≥3 falls in last year) and those with unstable medical conditions were excluded, as were those already reaching the UK Government recommended levels of physical activity (PA) for health.

METHODS

Baseline assessment (including assessment of health, function and previous falls) occurred before randomisation; the intervention period lasted 24 weeks and there was an immediate post-intervention assessment; participants were followed up every six months for 24 months. Falls data were analysed using negative binomial modelling.

OUTCOME MEASURES

Falls data were collected prospectively during the intervention period by 4-weekly diaries (6 in total). Falls recall was recorded at the 3-monthly follow-ups for a total of 24 months. Balance was measured at baseline and at the end of the intervention period using the Timed Up & Go and Functional Reach tests. Balance confidence (CONFbal), falls risk (FRAT) and falls self-efficacy (FES-I) were measured by questionnaire at baseline and at all subsequent assessment points.

RESULTS

294 participants (24%) reported one or two falls in the previous year. There was no increase in falls in either exercise group compared to UC during the intervention period (resulting from increased exposure to risk). The FaME arm experienced a significant reduction in injurious falls compared to UC (incidence rate ratio (IRR) 0.55, 95% CI 0.31, 0.96; p=0.04) and this continued during the 12 months after the end of the intervention (IRR 0.73, 95% CI 0.54, 0.99; p=0.05). There was also a significant reduction in the incidence of all falls (injurious and non-injurious) in the FaME arm compared with UC (IRR 0.74, 95% CI 0.55, 0.99; p=0.04) in the 12 month period following the cessation of the intervention. There was a non-significant reduction in the incidence of all falls in the OEP arm compared with UC (IRR 0.76, 95% CI 0.53, 1.09; p=0.14) in the 12 months following the cessation of the intervention. The effects on falls did not persist at the 24 months assessment in either exercise arm. However, when those in the FaME group who continued to achieve 150min of MVPA per week into the second post-intervention year were compared to those in the FaME group who did not maintain their physical activity, there was a significant reduction in falls incidence (IRR=0.49, 95% CI 0.30, 0.79; p=0.004). CONFbal was significantly improved at 12 months post intervention in both intervention arms compared with UC. There were no significant changes in any of the functional balance measures, FES-I or FRAT, between baseline and the end of the intervention period.

CONCLUSION

Community-dwelling older adults who joined an exercise intervention (FaME) aimed at increasing MVPA did not fall more during the intervention period, fell less and had fewer injurious falls in the 12 months after cessation of the intervention. However, 24 months after cessation of exercise, the beneficial effects of FaME on falls reduction ceased, except in those who maintained higher levels of MVPA. OEP exercise appears less effective at reducing falls in this functionally more able population of older adults.

Angiographic and Duplex Grading of Internal Carotid Stenosis: Can We Overcome the Confusion?

The stroke risk reduction benefit of surgical intervention in carotid occlusive disease has been validated in multicenter trials for various angiographically defined lesion severity categories. The two divergent angiographic grading methods used for internal carotid artery stenosis in these trials have caused confusion in the clinical application of their recommendations. Moreover, while today's highly accurate carotid duplex scanning can obviate the need for preoperative angiography in many cases, the duplex criteria must be tailored to achieve sufficiently reliable results on which therapeutic decisions can be made. This review offers a clarification of the discrepancies between the angiographic grading techniques and how their measurements of percent stenosis correlate to the duplex criteria needed to support the treatment decision-making process for carotid obliterative disease.

Human papillomavirus prevalence and genotypes in an opportunistically screened Irish female population

This study aims to evaluate human papillomavirus (HPV) prevalence and predominating genotypes in liquid-based cervical cytology samples from an Irish urban female population. In addition to use of routine cervical cytology testing, women are screened for HPV using the MY09/11 primers for the HPV L1 gene and primers for beta-globin amplification in a multiplex format. Overall, 996 women between the ages of 16 and 72 years (average age: 35) are included in the study and HPV prevalence was 19.8%. Cytology results showed that 88.9% were normal, 9% borderline or mild dyskaryosis, 1.1% moderate dyskaryosis and 0.9% severe dyskaryosis. Human papillomavirus prevalence in women under 25 was 31%, reducing to 23% in women in the 25-35 age group and to 11% in women over 35. Human papillomavirus prevalence increased with grade of cytology from 11.4% (normal) through 85.4% (borderline), 84% (mild), 100% (moderate) to 100% (severe dyskaryosis). HPV 16 (20%) and 18 (12%) were the most common high-risk types detected in the study. Other common high-risk types were (in descending order) HPV 66, 33, 53, 31 and 58. HPV 66 was associated with the detection of borderline abnormalities by cytology. This is the first population-based study of HPV prevalence in the normal healthy cervical screening population in the Republic of Ireland.

Lipotransfer for radiation-induced skin fibrosis

BACKGROUND

Radiation-induced fibrosis (RIF) is a late complication of radiotherapy that results in progressive functional and cosmetic impairment. Autologous fat has emerged as an option for soft tissue reconstruction. There are also sporadic reports suggesting regression of fibrosis following regional lipotransfer. This systematic review aimed to identify cellular mechanisms driving RIF, and the potential role of lipotransfer in attenuating these processes.

METHODS

PubMed, OVID and Google Scholar databases were searched to identify all original articles regarding lipotransfer for RIF. All articles describing irradiated fibroblast or myofibroblast behaviour were included. Data elucidating the mechanisms of RIF, role of lipotransfer in RIF and methods to quantify fibrosis were extracted.

RESULTS

Ninety-eight studies met the inclusion criteria. A single, definitive model of RIF is yet to be established, but four cellular mechanisms were identified through in vitro studies. Twenty-one studies identified connective tissue growth factor and transforming growth factor β1 cytokines as drivers of fibrotic cascades. Hypoxia was demonstrated to propagate fibrogenesis in three studies. Oxidative stress from the release of reactive oxygen species and free radicals was also linked to RIF in 11 studies. Purified autologous fat grafts contain cellular and non-cellular properties that potentially interact with these processes. Six methods for quantifying fibrotic changes were evaluated including durometry, ultrasound shear wave elastography, thermography, dark field imaging, and laser Doppler and laser speckle flowmetry.

CONCLUSION

Understanding how lipotransfer causes regression of RIF remains unclear; there are a number of new hypotheses for future research.

Comparison between insulin resistance indices and carotid and femoral atherosclerosis: a cross-sectional population study

AIM

The aim of this study was to investigate the association between commonly used insulin resistance (IR) indices and the presence and extent of carotid and femoral atherosclerosis in a general population setting.

METHODS

Cross-sectional analysis of 762 volunteers from the ongoing epidemiological Cyprus Study (46.6% male; mean age=60.5±10.2). 1) Carotid intima-media thickness (IMTcc), 2) carotid and femoral atherosclerotic plaque presence, 3) total plaque area in the carotid/femoral bifurcations (sum of the largest plaques in each carotid/femoral bifurcation-SPAcar/fem), and 4) total plaque area in both carotid and femoral bifurcations (sum of the areas of the largest plaques present in each of the four bifurcations-SPA) were measured using ultrasound at baseline. The HOMA-IR, QUICKI and McAuley indices as well as fasting insulin levels were estimated and their quartiles were used in linear and logistic regression analysis.

RESULTS

All IR indices studied were strongly associated with IMTcc (P<0.01for all) even after adjustment for age and sex and exclusion of diabetic subjects. However, when looking at plaque presence and size (i.e.area) only the HOMA-IR and especially the McAuley Index were associated with both carotid plaque presence (ORadj=1.17; 95%CI=1.01 to 1.36; P=0.03 and ORadj=0.86; 95%CI=0.74 to 0.99; P=0.04 respectively) and area (ORadj=0.10; 95%CI=0.008 to 0.20; P=0.03 and ORadj=-0.11; 95%CI=-0.20 to -0.009; P=0.03 respectively), after adjustment. The McAuley Index remained a significant predictor of both carotid plaque presence and area even after exclusion of diabetic subjects (P=0.04).

CONCLUSION

Our results show that while all indices were associated with carotid IMT, supporting a strong role for IR in intimal-medial thickening, only the HOMA-IR and especially the McAuley Index were associated with both carotid plaque presence and area, after adjustment. This highlights the importance of including triglyceride levels in estimating the risk for atherosclerotic plaque in the carotids as well as the possible differences in determinants for atherosclerosis between arterial sites.

The threatened stomach: management of the acute gastric volvulus

INTRODUCTION

Acute presentation of gastric volvulus is a rare condition with a high mortality for acute ischaemia. This study was undertaken to investigate the acute management, diagnosis, and long-term outcomes of patients presenting with acute gastric volvulus.

METHODS

Cases were reviewed retrospectively from 2004 to 2014. Patients presenting as an emergency admission with acute gastric volvulus were included.

RESULTS

Thirty-six patients were included, five of whom had previous surgery. The mean age was 71 years old. All patients presented with vomiting and chest/epigastric pain. CT was diagnostic in all 26 patients. Barium swallow was diagnostic in two/four patients. OGD was diagnostic in 9 of 20 patients. All patients had an NG tube placed, and eight patients were treated conservatively and made a full recovery. Twenty-nine patients proceeded to surgery. Nine had a laparoscopic repair with two open conversions. Four patients had gastric necrosis, and all had open surgery with resection. Three patients had a mediastinal perforation, and one patient required an additional thoracotomy. All patients with viable stomach had a hiatal repair (where appropriate), 11 had a gastropexy, and 11 had a fundoplication. Mortality for gastric necrosis/perforation was 30 %. Mean postoperative stay was 4 days for laparoscopic repair and 8 days for uncomplicated open surgery. Nine of twenty-nine had transient dysphagia postoperatively. Three of eight patients treated conservatively had an elective procedure subsequently.

CONCLUSIONS

Acute paraoesophageal hiatus hernia requires early resuscitation and diagnosis. CT should be favoured in assessment, and an NG tube placed promptly. A conservative management may be considered safely in stable patients. Surgical management should be prompt for unstable patients. Gastric ischaemia or perforation has a mortality of 30 %. Laparoscopic repair has a shorter postoperative stay, but has a higher recurrence rate. Surgery for patients without gastric ischaemia has good long-term outcomes with minimal morbidity.

Diagnostic accuracy of placental growth factor and ultrasound parameters to predict the small-for-gestational-age infant in women presenting with reduced symphysis-fundus height

OBJECTIVES

To assess the diagnostic accuracy of placental growth factor (PlGF) and ultrasound parameters to predict delivery of a small-for-gestational-age (SGA) infant in women presenting with reduced symphysis-fundus height (SFH).

METHODS

This was a multicenter prospective observational study recruiting 601 women with a singleton pregnancy and reduced SFH between 24 and 37 weeks' gestation across 11 sites in the UK and Canada. Plasma PlGF concentration < 5(th) centile, estimated fetal weight (EFW) < 10(th) centile, umbilical artery Doppler pulsatility index > 95(th) centile and oligohydramnios (amniotic fluid index < 5 cm) were compared as predictors for a SGA infant < 3(rd) customized birth-weight centile and adverse perinatal outcome. Test performance statistics were calculated for all parameters in isolation and in combination.

RESULTS

Of the 601 women recruited, 592 were analyzed. For predicting delivery of SGA < 3(rd) centile (n = 78), EFW < 10(th) centile had 58% sensitivity (95% CI, 46-69%) and 93% negative predictive value (NPV) (95% CI, 90-95%), PlGF had 37% sensitivity (95% CI, 27-49%) and 90% NPV (95% CI, 87-93%); in combination, PlGF and EFW < 10(th) centile had 69% sensitivity (95% CI, 55-81%) and 93% NPV (95% CI, 89-96%). The equivalent receiver-operating characteristics (ROC) curve areas were 0.79 (95% CI, 0.74-0.84) for EFW < 10(th) centile, 0.70 (95% CI, 0.63-0.77) for low PlGF and 0.82 (95% CI, 0.77-0.86) in combination.

CONCLUSIONS

For women presenting with reduced SFH, ultrasound parameters had modest test performance for predicting delivery of SGA < 3(rd) centile. PlGF performed no better than EFW < 10(th) centile in determining delivery of a SGA infant.

Risk of Thromboembolism Following Body-Contouring Surgery After Massive Weight Loss

BACKGROUND

"Postbariatric" patients are at significant risk for increased postoperative complications. This study aimed to define the risk of venous thromboembolism following body-contouring surgery after massive weight loss.

METHODS

A retrospective analysis was performed on all patients who had undergone all forms of body-contouring procedures after massive weight loss between January 2005 and August 2012 at St George's Hospital, South West London, United Kingdom. Data were collected on patient demographics, comorbidities, risks factors for thromboembolism, preoperative and postoperative body mass index, and type of surgery.

RESULTS

A total of 135 operations were performed on 53 patients (43 females, 10 male), with an average age of 44.8 years (range, 26-56 years). Most had staged procedures including 55 abdominoplasties, 23 brachioplasties, 31 thigh lifts, 14 lower-body lifts, and 12 mastopexies. All patients received venous thromboembolism prophylaxis postoperatively including low-molecular-weight heparin (dalteparin) within an average of 22.5 hours after surgery and the application of intraoperative graduated compression stockings. Patients received dalteparin for an average of 4 days (range, 2-14 days), which correlated to their length of stay. One patient had a deep venous thrombosis 14 days postoperatively and then 2 days later developed a nonfatal pulmonary embolus, giving a venous thromboembolism prevalence of 0.74% (1/135).

CONCLUSIONS

The clinically apparent venous thromboembolism prevalence was low among patients undergoing body-contouring procedures after massive weight loss in this study. We provide evidence of a successful algorithm to prevent venous thromboembolism for patients undergoing body-contouring procedures after massive weight loss.