A study of work stress, patient handling activities and the risk of low back pain among nurses in Hong Kong

RATIONALE

Low back pain (LBP) remains a common and costly problem among the nursing profession. Several studies have indicated that LBP is attributed to mentally straining or demanding work, fatigue or exhaustion or general work satisfaction.

AIMS

This study aims to measure the magnitude of LBP among Hong Kong nurses and its association with the work-related psychological strain and patients handling activities. RESEARCH METHODS AND MEASURES: A cross-sectional study of Hong Kong hospital nurses was conducted. Three hundred and seventy-seven nurses were recruited from six district hospitals. They were registered nurses or enrolled nurses working full-time for at least 1 month in the current ward. One hundred and seventy-eight (47.2%) study subjects were randomly selected from two district hospitals and 199 (52.8%) study nurses made up the convenience sample. Possible bias from psychological distress, socio-demographics and lifestyle factors was controlled for. Data were collected by face-to-face interviews. The data included work factors (both psychological stress and patient handling activities related to work), demographics, psychological distress and lifestyle factors and the occurrence of LBP.

RESULTS

Of the 377 nurses interviewed, 153 (40.6%) reported having LBP within the last 12 months. With symptoms of LBP as the outcome, risks were increased where nurses self-reported that they only occasionally or never enjoyed their work [adjusted odds ratio (OR) 2.07], where frequent manual repositioning of patients on the bed was required (adjusted OR 1.84) and where they were required to assist patients while walking (adjusted OR 2.11) after adjustment for other potential confounders.

CONCLUSION

The results indicate that an association exists between work stress, manual lifting and LBP prevalence. The main route to prevention of LBP among nurses is likely to lie in improved ergonomics and psychological health in their work place. Good posture and correct transferring techniques in ward situations should be reinforced with hands-on practice performed on nurses' common types of clients.

Green tea extract treatment alleviates ocular inflammation in a rat model of endotoxin-induced uveitis

Green tea extract (GTE) ingested by rats exerted anti-oxidative activities in various ocular tissues as shown in our previous studies. The present work investigated anti-inflammatory effects of GTE on endotoxin-induced uveitis (EIU). EIU was generated in adult rats by a footpad injection of 1 mg/kg lipopolysaccharide (LPS). Oral administration of GTE (550 mg/kg) was given one, two or four times after LPS injection. Twenty-four hours later, LPS produced severe hyperemia and edema in the iris. Immunocytochemical examinations showed an accumulation of infiltrating cells in the aqueous humor that were immunopositive for cluster of differentiation 43 (CD43) and CD68, markers for leucocytes and macrophages, respectively. Analyses of the aqueous humor showed an increase in pro-inflammatory mediators including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1). GTE treatments improved the clinical manifestations and reduced infiltrating cells and protein exudation in the aqueous humor, which were not observed under half dose of GTE (275 mg/kg). The number of CD68 positive macrophages residing in the iris and ciliary was also reduced. GTE suppressed production of TNF-α, IL-6 and MCP-1 in the aqueous humor, which was associated with a down-regulation of LPS receptor complex subunits, Toll-like receptor 4 (TLR-4) and CD14, and suppression of nuclear factor-kappa Bp65 (NF-κBp65) in the iris and ciliary body. Our findings show that GTE is a potent anti-inflammatory agent against the inflammation of EIU, and suggest a potential use in treatment of acute uveitis.

Analysis of choriocapillaris perfusion and choroidal layer changes in patients with chronic central serous chorioretinopathy randomised to micropulse laser or photodynamic therapy

PURPOSE

The purpose of this study was to investigate the signal changes in choriocapillaris flow deficits and choroidal thickness changes using swept-source optical coherence tomography angiography (OCTA) following different treatments.

DESIGN

A double-blind, randomised controlled trial.

METHODS

Patients with unilateral chronic central serous chorioretinopathy (CSC) were randomised to receive subthreshold micropulse laser therapy (MLT) or half-dose photodynamic therapy (PDT). Choroidal thickness and choriocapillaris flow deficit signals were investigated.

RESULTS

Eighteen patients were randomised into the MLT group and 15 patients into the PDT group. Areas with flow deficit signals were identified in all baseline OCTA images of the choriocapillaris, with mean areas of 0.420 and 0.465 mm² in the MLT and PDT groups, respectively. These flow deficit signal areas were significantly reduced at 6 months (p=0.011) in the MLT group and at 3 months (p=0.008) in the PDT group. Patients from the PDT group were shown to have smaller flow deficit areas than patients from the MLT group at all time points after treatment (p=0.001, analyses of variance). The mean choroidal volume of the fovea showed a significant reduction at 1 month (p=0.003), 3 months (p=0.199) and 6 months (p=0.006) in the PDT group.

CONCLUSION

The flow deficit areas identified in the choriocapillaris layer may suggest possible relative choroidal ischaemia. With measurement of choroidal volume reduction and faster rates of flow deficit area change, PDT has a stronger effect than MLT in promoting choriocapillaris recovery.

Retinal vasculitis associated with chickenpox

PURPOSE

To report retinal vasculitis in a young, immunocompetent Asian female adult with chickenpox.

METHODS

Interventional case report. A 32-year-old woman had chickenpox 2 weeks before blurred vision in the left eye. The visual acuity was 20/20 for the right eye and 30/50 for the left eye. The left eye presented keratic precipitates, moderate (2+) cells in the anterior chamber and numerous cells (3+) in the vitreous. The disk was normal. Perivenous exudation was noted mainly in the inferior retina. The sheathed retinal vessels showed late staining but no remarkable leakage on fluorescein angiography. The right eye was normal.

RESULTS

After treatment with acyclovir for 10 days, the visual acuity in the left eye improved to 20/20, and the vasculitis resolved.

CONCLUSION

Retinal vasculitis may present as a complication of primary varicella infection in an immunocompetent adult.

Growth hormone releasing hormone signaling promotes Th17 cell differentiation and autoimmune inflammation

Dysregulation of Th17 cell differentiation and pathogenicity contributes to multiple autoimmune and inflammatory diseases. Previously growth hormone releasing hormone receptor (GHRH-R) deficient mice have been reported to be less susceptible to the induction of experimental autoimmune encephalomyelitis. Here, we show GHRH-R is an important regulator of Th17 cell differentiation in Th17 cell-mediated ocular and neural inflammation. We find that GHRH-R is not expressed in naïve CD4⁺ T cells, while its expression is induced throughout Th17 cell differentiation in vitro. Mechanistically, GHRH-R activates the JAK-STAT3 pathway, increases the phosphorylation of STAT3, enhances both non-pathogenic and pathogenic Th17 cell differentiation and promotes the gene expression signatures of pathogenic Th17 cells. Enhancing this signaling by GHRH agonist promotes, while inhibiting this signaling by GHRH antagonist or GHRH-R deficiency reduces, Th17 cell differentiation in vitro and Th17 cell-mediated ocular and neural inflammation in vivo. Thus, GHRH-R signaling functions as a critical factor that regulates Th17 cell differentiation and Th17 cell-mediated autoimmune ocular and neural inflammation.

Systemic and Ocular Anti-Inflammatory Mechanisms of Green Tea Extract on Endotoxin-Induced Ocular Inflammation

Introduction

Green tea extract (GTE) alleviated ocular inflammations in endotoxin-induced uveitis (EIU) rat model induced by lipopolysaccharide (LPS) but the underlying mechanism is unclear.

Objectives

To investigate the systematic and local mechanisms of the alleviation by untargeted metabolomics using liquid chromatography-tandem mass spectrometry.

Methods

Sprague-Dawley rats were divided into control group, LPS treatment group, and LPS treatment group treated with GTE two hours after LPS injection. The eyes were monitored by slip lamp and electroretinography examination after 24 hours. The plasma and retina were collected for metabolomics analysis.

Results

In LPS treated rats, the iris showed hyperemia. Plasma prostaglandins, arachidonic acids, corticosteroid metabolites, and bile acid metabolites increased. In the retina, histamine antagonists, corticosteroids, membrane phospholipids, free antioxidants, and sugars also increased but fatty acid metabolites, N-acetylglucosamine-6-sulphate, pyrocatechol, and adipic acid decreased. After GTE treatment, the a- and b- waves of electroretinography increased by 13%. Plasma phosphorylcholine lipids increased but plasma prostaglandin E1, cholanic metabolites, and glutarylglycine decreased. In the retina, tetranor-PGAM, pantothenic derivatives, 2-ethylacylcarinitine, and kynuramine levels decreased but anti-oxidative seleno-peptide level increased. Only phospholipids, fatty acids, and arachidonic acid metabolites in plasma and in the retina had significant correlation (p < 0.05, r > 0.4 or r < -0.4).

Conclusions

The results showed GTE indirectly induced systemic phosphorylcholine lipids to suppress inflammatory responses, hepatic damage, and respiratory mitochondrial stress in EIU rats induced by LPS. Phospholipids may be a therapeutic target of GTE for anterior chamber inflammation.

Quantitative Characterization of Autoimmune Uveoretinitis in an Experimental Mouse Model

Purpose

To accurately evaluate the autoimmune inflammation, we aim to develop three quantitative measurements to monitor the inflammatory changes in the retina: retinal-choroidal thickness, major retinal vessel diameter, and electroretinography amplitudes.

Methods

During a 21-day experimental period, eyes were examined by confocal scanning laser ophthalmoscopy, optical coherence tomography, fundus fluorescein angiography, and electroretinography in living mice, which were then subsequently killed for histologic assessments.

Results

On day 21 postimmunization, inflammation was observed both in vivo and in vitro. Fold change of retinal-choroidal thickness and major retinal vessel diameter in experimental autoimmune uveoretinitis mice were significantly greater than controls (P < 0.001). Both scotopic and photopic electroretinography amplitudes were significantly attenuated when compared with control mice (P < 0.01). Our results showed that these three quantifiable indicators provided an objective and accurate evaluation of autoimmune inflammation, which are in good correlations with the reported clinical and histopathologic scoring systems (P < 0.05).

Conclusions

These three indicators will be useful to detect the small but significant differences in the severity of experimental autoimmune uveoretinitis for future longitudinally therapeutic studies.

Improving the quality of electroretinogram recordings using active electrodes

The aim of this study was to compare the quality of electroretinogram (ERG) recordings using a custom built active electrode with attached amplifier versus a standard (passive) ERG electrode. Scotopic and photopic ERG responses were recorded from five adult albino rabbits using a custom built active electrode on one eye and a passive electrode on the other. For the active electrode, the ERG-jet electrode (Universo S.A., La Chaux-De-Fonds, Switzerland) was used as the transducer with the cable cut short and soldered directly to the input of a customized amplifier. The passive electrode was a standard ERG jet electrode. The signal to noise ratio and reproducibility of ERGs were compared. The noise was significantly lower in the active electrode compared to the passive electrode (p = 0.009) resulting in signals being recorded at lower stimulation strengths with the active electrode. The scotopic a-wave was significantly larger in the active electrode at all supra-threshold stimulation intensities (p < 0.05) and the scotopic b-wave amplitudes were also higher in the active electrode at all supra-threshold stimulation intensities but was only statistically significant between -3.25 and -1 log cd.s.m^-2 (p < 0.05). The photopic a- and b-wave amplitudes were also higher in the active electrode and statistically significant between -0.75 and 0.48 log cd.s.m^-2 for the a-wave and -1.25 to -1 log cd.s.m^-2 for the b-wave (p < 0.05). The intra-observer repeatability, inter-sessions reproducibility and reliability of the signals were better in the active electrode as evidenced by lower coefficient of variation (CV) and coefficient of repeatability (CR) with high intra-class correlation coefficient (ICC) of the a- and b-wave parameters of the active electrode. These findings suggest that the custom built active ERG electrode produces less noise than the passive electrode, allowing responses to be recorded at lower stimulation strengths. It produces greater signal amplitudes and improved reproducibility and is therefore a better device for investigating retinal function.

A sclerocornea-associated RAD21 variant induces corneal stroma disorganization

Sclerocornea is a cornea opacification disorder. Disorganized corneal stroma fibrils are observed in patients' cornea. Previously we identified a RAD21^C1348T variant that is associated with a peripheral sclerocornea pedigree. To explore whether this RAD21 variant can induce sclerocornea-related phenotype, and to investigate the possible mechanisms of such phenotype, the orthologous rad21 wild-type and variant mRNAs were injected into Xenopus laevis embryos and the developed eyes were subjected for histological examination. Transmission electron microscopy was applied for corneal stroma organization check. rad21 is highly expressed in the eye region during X. laevis development. Disrupted eye development was observed in the rad21 variant injected embryos. Disorganized corneal stroma and decreased diameters of collagen fibrils were observed in the rad21 variant injected X. laevis eyes. These eye defects can be rescued by overexpression of the wild-type rad21. Histological examination found stroma attracting center, a key structure in X. laevis corneal development, was impaired in rad21 variant injected embryos. Our results suggest a key role of RAD21 during corneal development. Our data indicates the RAD21^R450C variant contributes to peripheral sclerocornea by disturbing collagen fibril organization in the corneal stroma.

Abstract 4417: The role of EBV infection in aerobic glycolysis in nasopharyngeal carcinoma

Accumulating evidence indicates that oncogenic viral protein exerts a crucial role in activating aerobic glycolysis during tumorigenesis, but the underlying mechanisms are largely undefined. The Epstein-Barr virus (EBV)-encoded latent membrane protein 1 (LMP1) is a trans-membrane protein with potent cell signaling properties and has tumorigenic transformation property. Activation of NF-κB is a major signaling pathway mediating many downstream transformation properties of LMP1. Here we report that activation of mTORC1 by LMP1 is a key modulator for activation of NF-κB signaling to mediate aerobic glycolysis. NF-κB activation is involved for LMP1-induced upregulation of glucose transptor-1 (Glut-1) transcription and growth of nasopharyngeal carcinoma (NPC) cells. Collectively, blocking the activity of mTORC1 signaling effectively suppressed LMP1-induced NF-κB activation and Glut-1 transcription. Interfering NF-κB signaling has no effect on mTORC1 activity but effectively altered Glut-1 transcription. Luciferase promoter assay of Glut-1 also confirmed that Glut-1 is a direct target gene of NF-κB signaling. Furthermore, we demonstrated that the LMP1 C-terminal activating region (CTAR) 2 is the key domain involved in mTORC1 activation, mainly through IKKβ-mediated phosphorylation of TSC2 at Ser939. Depletion of Glut-1 effectively led to suppression of aerobic glycolysis, inhibition of cell proliferation, colony formation, and attenuation of tumorigenic growth property of LMP1-expressing nasopharyngeal epithelial (NPE) cells. These findings suggest that targeting the signaling axis of mTORC1/NF-κB/Glut-1 represents a novel therapeutic target against NPC.

Acknowledgement: 96 800x600 This project was supported by the General Research Fund (HKU 779810M, 17120814 and 17161116), CRF equipment grant (1061402980, Health and Medical Research Fund of Hong Kong (12110782), AoE grant (AoE/M-06/08) and TBRS grant (T12-401/13-R). We thank Prof. Dongyan Jin (Department of Biochemistry, The University of Hong Kong) for the kind gifts of IKK related plasmids and Prof. Zhenguo Wu (Division of Life Science, The Hong Kong University of Science and Technology) for the discussion and interpretation of the data. We also thank Mr. Tony Chan for his technical support.

Note: This abstract was not presented at the meeting.

Citation Format: George S. Tsao, Jun Zhang, Lin Xia, C Tsang, Weitao Lin, Y Yip, W Deng, K Lo, M Lung. The role of EBV infection in aerobic glycolysis in nasopharyngeal carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4417. doi:10.1158/1538-7445.AM2017-4417

Amelioration of Functional, Metabolic, and Morphological Deterioration in the Retina following Retinal Detachment by Green Tea Extract

Retinal detachment (RD) can result in the loss of photoreceptors that cause vision impairment and potential blindness. This study explores the protective effects of the oral administration of green tea extract (GTE) in a rat model of RD. Various doses of GTE or epigallocatechin gallate (EGCG), the most active ingredient in green tea catechins, were administered to Sprague Dawley (SD) rats with experimentally induced retinal detachment. The rats received sub-retinal injections of hyaluronic acid (0.1%) to induce RD and were given different doses of GTE and EGCG twice daily for three days. Notably, a low dose of GTE (142.9 mg/kg) caused significantly higher signal amplitudes in electroretinograms (ERGs) compared to higher GTE doses and any doses of EGCG. After administration of a low dose of GTE, the outer nuclear layer thickness, following normalization, of the detached retina reduced to 82.4 ± 8.2% (Mean ± SEM, p < 0.05) of the thickness by RD treatment. This thickness was similar to non-RD conditions, at 83.5 ± 4.7% (Mean ± SEM) of the thickness following RD treatment. In addition, the number of TUNEL-positive cells decreased from 76.7 ± 7.4 to 4.7 ± 1.02 (Mean ± SEM, p < 0.0001). This reduction was associated with the inhibition of apoptosis through decreased sphingomyelin levels and mitigation of oxidative stress shown by a lowered protein carbonyl level, which may involve suppression of HIF-1α pathways. Furthermore, GTE showed anti-inflammatory effects by reducing inflammatory cytokines and increasing resolving cytokines. In conclusion, low-dose GTE, but not EGCG, significantly alleviated RD-induced apoptosis, oxidative stress, inflammation, and energy insufficiency within a short period and without affecting energy metabolism. These findings suggest the potential of low-dose GTE as a protective agent for the retina in RD.