Adipocyte differentiation of 3T3-L1 cells under tenofovir alafenamide, tenofovir disoproxil fumarate, and integrase strand transfer inhibitors selective challenge: an in-vitro model

OBJECTIVE

Integrase strand transfer inhibitors (INSTIs) are a class of antiretroviral therapy (ART) medications with a good tolerability profile and a high genetic barrier to HIV drug resistance. However, several studies report significant weight gain among persons receiving INSTI-based ART regimens compared with other regimens.

DESIGN

In-vitro model of adipogenesis.

METHODS

We used 3T3-L1 cells to investigate the effects of the nucleoside reverse transcriptase inhibitors (NRTIs) tenofovir disoproxil fumarate (TDF) and tenofovir alafenamide (TAF), alone or in combination with INSTIs: raltegravir (RAL), elvitegravir (ELV), dolutegravir (DTG), and bictegravir (BIC) on adipose differentiation. To monitor adipocyte differentiation, expression levels of PPARɣ and C/EBPα and the intracellular lipid accumulation by Red Oil staining were used. Furthermore, we evaluated the immunohistochemical expression of ER-TR7, a fibroblastic marker, after INSTIs treatment.

RESULTS

Compared with control, INSTIs were able to increase adipogenesis, especially RAL and ELV. TAF and TDF inhibited adipogenesis alone and in combination with INSTIs. This ability was more evident when TAF was used in combination with DTG and BIC. Finally, INSTIs increased the expression of ER-TR7 compared with control and cells treated with TAF or TDF.

CONCLUSION

Our data support the evidence that in-vitro challenge of 3T3-L1 cells with INSTIs is able to increase adipocytic differentiation and to drive a number of these cells toward the expression of fibroblastic features, with a different degree according to the various drugs used whereas TAF and TDF have an antagonistic role on this phenomenon.

Antiinflammatory Activities of Curcumin and Spirulina: Focus on Their Role against COVID-19

Nutraceuticals have for several years aroused the interest of researchers for their countless properties, including the management of viral infections. In the context of the COVID-19 pandemic, studies and research on the antiviral properties of nutraceuticals have greatly increased. More specifically, over the past two years, researchers have focused on analyzing the possible role of nutraceuticals in reducing the risk of SARS-CoV-2 infection or mitigating the symptoms of COVID-19. Among nutraceuticals, turmeric, extracted from the rhizome of the Curcuma Longa plant, and spirulina, commercial name of the cyanobacterium Arthrospira platensis, have assumed considerable importance in recent years. The purpose of this review is to collect, through a search of the most recent articles on Pubmed, the scientific evidence on the role of these two compounds in the fight against COVID-19. In the last two years many hypotheses, some confirmed by clinical and experimental studies, have been made on the possible use of turmeric against COVID-19, while on spirulina and its possible role against SARS-CoV-2 infection information is much less. The demonstrated antiviral properties of spirulina and the fact that these cyanobacteria may modulate or modify some mechanisms also involved in the onset of COVID-19, lead us to think that it may have the same importance as curcumin in fighting this disease and to speculate on the possible combined use of these two substances to obtain a synergistic effect.

Genetic architecture of a composite beef cattle population

Composite breeds are widely used in the beef industry. Composites allow producers to combine desirable traits from the progenitor breeds and simplify herd management, without repeated crossbreeding and maintenance of purebreds. In this study, genomic information was used to evaluate the genetic composition and characteristics of a three-breed beef cattle composite. This composite population referred to as Composite Gene Combination (CGC) consisted of 50% Red Angus, 25% Charolais, 25% Tarentaise. A total of 248 animals were used in this study CGC (n=79), Red Angus (n=61), Charolais (n=79) and Tarentaise (n=29). All animals were genotyped with 777k HD panel. Principal component and ADMIXTURE analyses were carried out to evaluate the genetic structure of CGC animals. The ADMIXTURE revealed the proportion of Tarentaise increased to approximately 57% while Charolais decreased to approximately 5%, and Red Angus decreased to 38% across generations. To evaluate these changes in the genomic composition across different breeds and in CGC across generations runs of homozygosity (ROH) were conducted. This analysis showed Red Angus to have the highest total length of ROH segments per animal with a mean of 349.92 Mb and lowest in CGC with a mean of 141.10 Mb. Furthermore, it showed the formation of new haplotypes in CGC around the sixth generation. Selection signatures were evaluated through Fst and HapFlk analyses. Several selection sweeps in CGC were identified especially in chromosomes 5 and 14 which have previously been reported to be associated with coat color and growth traits. The study supports our previous findings that progenitor combinations are not stable over generations and that either direct or natural selection plays a role in modifying the progenitor proportions. Furthermore, the results showed that Tarentaise contributed useful attributes to the composite in a cool semi-arid environment and suggests a re-exploration of this breed's role may be warranted.

ScoMorphoFISH: A deep learning enabled toolbox for single-cell single-mRNA quantification and correlative (ultra-)morphometry

Increasing the information depth of single kidney biopsies can improve diagnostic precision, personalized medicine and accelerate basic kidney research. Until now, information on mRNA abundance and morphologic analysis has been obtained from different samples, missing out on the spatial context and single‐cell correlation of findings. Herein, we present scoMorphoFISH, a modular toolbox to obtain spatial single‐cell single‐mRNA expression data from routinely generated kidney biopsies. Deep learning was used to virtually dissect tissue sections in tissue compartments and cell types to which single‐cell expression data were assigned. Furthermore, we show correlative and spatial single‐cell expression quantification with super‐resolved podocyte foot process morphometry. In contrast to bulk analysis methods, this approach will help to identify local transcription changes even in less frequent kidney cell types on a spatial single‐cell level with single‐mRNA resolution. Using this method, we demonstrate that ACE2 can be locally upregulated in podocytes upon injury. In a patient suffering from COVID‐19‐associated collapsing FSGS, ACE2 expression levels were correlated with intracellular SARS‐CoV‐2 abundance. As this method performs well with standard formalin‐fixed paraffin‐embedded samples and we provide pretrained deep learning networks embedded in a comprehensive image analysis workflow, this method can be applied immediately in a variety of settings.

MO064: Expression Studies on Magi2 in Different FSGS Models

BACKGROUND AND AIMS

MAGI2 is a tight junction protein and member of the membrane-associated guanylate kinase (MAGUK) family. In the glomerulus, it is exclusively expressed in podocytes and interacts with the slit diaphragm protein nephrin. Recent studies and podocyte-specific MAGI2 knockout mice have demonstrated the essential role of this protein in the glomerulus. The aim of this work was to study the expression of MAGI2 in different focal segmental glomerulosclerosis (FSGS) mouse models, in the GlomAssay, in a FSGS-like zebrafish model, and in human biopsies of patients suffering from minimal change disease and FSGS. Additionally, using CRISPR/Cas9 knockout of magi2 and nephrin in zebrafish, we investigated the influence of both proteins on each other’s localization.

METHOD

We used nephrotoxic serum (NTS) as well as uninephrectomy DOCA/salt-induced hypertension as murine models. The podocyte-specific nitroreductase/metronidazole zebrafish model was used to induce FSGS-like disease in zebrafish upon partial podocyte-depletion. MAGI2 expression was evaluated in kidney biopsies of patients affected by minimal change disease (MCD), primary and secondary FSGS. Slides were imaged using confocal laser scanning and super-resolution 3D-structured illumination microscopy (3D-SIM). Filtration slit density (FSD) was measured on human biopsies by PEMP (podocyte exact morphology measurement procedure). MAGI2/nephrin ratio measurements were performed with a customized macro for the ImageJ-based platform FIJI. Magi2 expression was studied in the GlomAssay. To evaluate the interaction between magi2 and nephrin in the zebrafish model, the respective proteins were knocked-out using CRISPR/Cas9. The knockout was validated by RT–PCR and the expression of these two proteins in both lines was analyzed by immunofluorescence staining. Proteinuria was assessed using the excretion of eGFP-tagged vitamin D-binding protein from the vasculature and reuptake in proximal tubule cells.

RESULTS

MAGI2 was expressed in a linear pattern along the filtration slit and colocalized with nephrin in all three species investigated (human, mouse and zebrafish) (3D-SIM in Fig. 1). MAGI2 was significantly downregulated in NTS-induced nephritis, as well as in uninephrectomized and DOCA/salt-treated mice. In the GlomAssay, Magi2 was significantly downregulated in dedifferentiated podocytes after 6 days in cell culture due to podocyte dedifferentiation. A reduction of MAGI2 was found in human biopsies of patients suffering from primary FSGS, but not in MCD and secondary FSGS, respectively. In addition, we found that magi2 was downregulated in zebrafish larvae using our FSGS-like zebrafish model. When we examined the effect of nephrin on magi2 expression and vice versa, we found that magi2 expression was unchanged in nephrin-KO larvae, whereas nephrin expression was significantly reduced in MAGI2a-KO larvae.

CONCLUSION

Here, we have shown that the expression of MAGI2 in the glomerulus of different species such as zebrafish, mice and humans is associated with the expression of nephrin. By using knockout larvae, we showed that nephrin expression is dependent on Magi2 and not vice versa. Since the expression of Magi2 seems to be specifically regulated depending on the podocytopathy investigated, we propose a role for MAGI2 to distinguish between different glomerulopathies.

Expression of Matrix Metalloproteinases and Their Tissue Inhibitors in Chronic Rhinosinusitis With Nasal Polyps: Etiopathogenesis and Recurrence

Chronic rhinosinusitis with nasal polyps is a multifactorial disease of the nasal and paranasal sinus mucosa and it includes, as comorbidities, anatomic and morphologic alterations, allergic rhinitis, and immunologic diseases. We investigated matrix metalloproteinases (MMP-2, MMP-7, and MMP-9) and their tissue inhibitors (TIMP-1 and TIMP-2) concentration in different etiopathogenetical groups of patients with nasal polyposis (NP) in relation to recurrence after sinonasal surgery. The study group consisted of 45 patients with NP (those with allergic rhinitis, nonallergic rhinitis and asthma or nonallergic rhinitis, and obstruction of osteomeatal complex [OMC]) who underwent endonasal sinus surgery. We also collected 10 patients who underwent septoplasty as control. Immunohistochemistry of nasal mucosa fragments, Western blotting, and polymerase chain reaction analysis showed increased MMPs levels (MMP-9 more than MMP-2 and MMP-7) and decreased tissue inhibitors of MMPs levels (TIMP-1 less than TIMP-2), in patients with chronic rhinosinusitis with nasal polyps compared with control group, in particular in patients with nonallergic rhinitis and asthma compared to those with allergic rhinitis and nonallergic rhinitis and obstruction of OMC. We observed a higher risk of recurrence in patients with nonallergic rhinitis and asthma than in those with allergic rhinitis and nonallergic rhinitis and obstruction of OMC after 36 months from surgery. In this research, we evaluated pathogenesis of NP related to MMPs and their inhibitors concentrations in polypoid tissue.

Super-resolved local recruitment of CLDN5 to filtration slits implicates a direct relationship with podocyte foot process effacement

Under healthy conditions, foot processes of neighbouring podocytes are interdigitating and connected by an electron‐dense slit diaphragm. Besides slit diaphragm proteins, typical adherens junction proteins are also found to be expressed at this cell‐cell junction. It is therefore considered as a highly specialized type of adherens junction. During podocyte injury, podocyte foot processes lose their characteristic 3D structure and the filtration slits typical meandering structure gets linearized. It is still under debate how this change of structure leads to the phenomenon of proteinuria. Using super‐resolution 3D‐structured illumination microscopy, we observed a spatially restricted up‐regulation of the tight junction protein claudin‐5 (CLDN5) in areas where podocyte processes of patients suffering from minimal change disease (MCD), focal and segmental glomerulosclerosis (FSGS) as well as in murine nephrotoxic serum (NTS) nephritis and uninephrectomy DOCA‐salt hypertension models, were locally injured. CLDN5/nephrin ratios in human glomerulopathies and NTS‐treated mice were significantly higher compared to controls. In patients, the CLDN5/nephrin ratio is significantly correlated with the filtration slit density as a foot process effacement marker, confirming a direct association of local CLDN5 up‐regulation in injured foot processes. Moreover, CLDN5 up‐regulation was observed in some areas of high filtration slit density, suggesting that CLND5 up‐regulation preceded the changes of foot processes. Therefore, CLDN5 could serve as a biomarker predicting early foot process effacement.

FC 017DEEP-LEARNING ENABLED QUANTIFICATION OF SINGLE-CELL SINGLE-MRNA TRANSCRIPTS AND CORRELATIVE SUPER-RESOLVED PODOCYTE FOOT PROCESS MORPHOMETRY IN ROUTINE KIDNEY BIOPSY SPECIMEN

Background and Aims

Although high-throughput single-cell transcriptomic analysis, super-resolution light microscopy and deep-learning methods are broadly used, the gold-standard to evaluate kidney biopsies is still the histologic assessment of formalin-fixed and paraffin embedded (FFPE) samples with parallel ultrastructural evaluation. Recently, we and others have shown that super-resolution fluorescence microscopy can be used to study glomerular ultrastructure in human biopsy samples. Additionally, in the last years mRNA in situ hybridization techniques have been improved to increase specificity and sensitivity to enable transcriptomic analysis with single-mRNA resolution (smFISH).

Method

For smFISH, we used the fluorescent multiplex RNAscope kit with probes targeting ACE2, WT1, PPIB, UBC and POLR2A. To find an on-slide reference gene, the normfinder algorithm was used. The smFISH protocol was combined with a single-step anti-podocin immunofluorescence enabled by VHH nanobodies. Podocytes were labeled by tyramide-signal amplified immunofluorescence using recombinant anti-WT1 antibodies. Slides were imaged using confocal laser scanning, as well as 3D structured illumination microscopy. Deep-learning networks to segment glomeruli and cell nuclei (UNet and StarDist) were trained using the ZeroCostDL4Mic approach. Scripts to automate analysis were developed in the ImageJ1 macro language.

Results

First, we show robust functionality of threeplex smFISH in archived routine FFPE kidney biopsy samples with single-mRNA resolution. As variations in sample preparation can negatively influence mRNA-abundance, we established PPIB as an ideal on-slide reference gene to account for different RNA-integrities present in biopsy samples. PPIB was chosen for its most stable expression in microarray dataset of various glomerular diseases determined by the Normfinder algorithm as well as its smFISH performance.

To segment glomeruli and to label glomerular and tubulointerstitial cell subsets, we established a combination of smFISH and immunofluorescence. As smFISH requires intense tissue digestion to liberate cross-linked RNAs, immunofluorescence protocols had to be adapted: For podocin, a small-sized single-step label approach enabled by small nanobodies and for WT1, tyramide signal amplification was used.

For enhanced segmentation performance, we used deep learning: First, a network was customized to recognize DAPI+ cell nuclei and WT1/DAPI+ podocyte nuclei. Second, a UNet was trained to segment glomeruli in podocin-stained tissue sections. Using these segmentation masks, we could annotate PPIB-normalized single mRNA transcripts to individual cells. We established an ImageJ script to automatize transcript quantification.

As a proof-of-principle, we demonstrate inverse expression of WT1 and ACE2 in glomerular vs. tubulointerstitial single cells. Furthermore, in the podocyte subset, WT1 highly clustered whereas no significant ACE2 expression was found under baseline conditions.

Additionally, when imaged with super-resolution microscopy, podocyte filtration slit morphology could be visualized The optical resolution was around 125 nm and therefore small enough to resolve individual foot processes. The filtration slit density as a podocyte-integrity marker did not differ significantly from undigested tissue sections proving the suitability for correlative podocyte foot process morphometry with single-podocyte transcript analysis.

Conclusion

Here we present a modular toolbox which combines algorithms for multiplexed, normalized single-cell gene expression with single mRNA resolution in cellular subsets (glomerular, tubulointerstitial and podocytes). Additionally, this approach enables correlation with podocyte filtration slit ultrastructure and gross glomerular morphometry.

The Matrilin-3 T298M mutation predisposes for post-traumatic osteoarthritis in a knock-in mouse model

OBJECTIVE

The human matrilin-3 T303M (in mouse T298M) mutation has been proposed to predispose for osteoarthritis, but due to the lack of an appropriate animal model this hypothesis could not be tested. This study was carried out to identify pathogenic mechanisms in a transgenic mouse line by which the mutation might contribute to disease development.

METHODS

A mouse line carrying the T298M point mutation in the Matn3 locus was generated and features of skeletal development in ageing animals were characterized by immunohistology, micro computed tomography, transmission electron microscopy and atomic force microscopy. The effect of transgenic matrilin-3 was also studied after surgically induced osteoarthritis.

RESULTS

The matrilin-3 T298M mutation influences endochondral ossification and leads to larger cartilage collagen fibril diameters. This in turn leads to an increased compressive stiffness of the articular cartilage, which, upon challenge, aggravates osteoarthritis development.

CONCLUSIONS

The mouse matrilin-3 T298M mutation causes a predisposition for post-traumatic osteoarthritis and the corresponding knock-in mouse line therefore represents a valid model for investigating the pathogenic mechanisms involved in osteoarthritis development.

OP0243 SERPINA3N LIMITS CARTILAGE DESTRUCTION IN OSTEOARTHRITIS BY INHIBITING MACROPHAGE-DERIVED LEUKOCYTE ELASTASE

Background:

Interleukin-6 (IL-6) plays an important role in osteoarthritis (OA). Transcriptomic analyses (RNAseq) revealed that SerpinA3N, a serine protease inhibitor, is a key target of IL-6 in chondrocyte.

Objectives:

This study aimed to examine the role of SerpinA3N and Leukocyte Elastase (Elane), a serine protease targeted by SerpinA3N, in cartilage destruction during OA.

Methods:

The role of SerpinA3N was investigated in the destabilization of medial meniscus (DMM) model of murine OA with 1) mice with conditional inducible knockdown ofSerpina3nin cartilage (Col2CreER;Serpina3nfl/flmice [ΔSerpina3nCol2]) and 2) C57BL/6 wild type (WT) mice treated with intra-articular injection of SerpinA3N (1,5 or 15 nM/week). OA joint lesions were assessed by histology (OARSI and synovitis scores) and micro-CT analysis (osteophyte volume, subchondral bone remodeling).

Because serine proteases targeted by SerpinA3N are not produced by murine chondrocytes,Elaneexpression (qRT-PCR) was determined in murine macrophages (Raw) stimulated or not by IL-6 (100 ng/ml). Recombinant SerpinA3N (30 nM) and a specific Elane inhibitor, Sivelestat (100 µg/ml) were used on cartilage explants treated by conditioned medium of macrophages pre-treated or not by IL-6 (CM–IL-6). Cartilage catabolism was determined by histology and matrix metalloproteinase MMP-3 production was evaluated by Western Blot and immunohistochemistry (IHC). Weekly intra-articular injections of Sivelestat (1mM) were performed in the DMM to determine the role of Elane in OA.

Results:

ΔSerpina3nCol2mice had more severe OA lesions than control littermates 6 weeks after DMM, with greater cartilage damage (mean±SD OARSI score: 5.6±0.4 vs 3.4±0.5, p=0.01), increased synovitis scores (3.0±0.3 vs 1.9±0.3, p=0.03) and bigger osteophytes (7.2±0.8x107 vs 3.8±0.8x107 µ3, p=0.048). Conversely, WT mice treated with intra-articular injections of SerpinA3N 15nM exhibited less severe cartilage loss than mice treated with PBS after DMM (OARSI score: 2.1±0.4 vs 3.9±0.5, p=0.02). Elane mRNA expression was increased in macrophages upon IL-6 stimulation. In cartilage explants, CM–IL-6 activated cartilage catabolism and MMP-3 production, and effect that was blunted by SerpinA3N and Sivelestat. Finally, mice treated with intra-articular injections of Sivelestat had less severe cartilage damage than those treated with PBS after DMM (OARSI score: 3.3±0.47 vs 5.8±0.53, p=0.0046).

Conclusion:

SerpinA3N protects against experimental OA via the inhibition of Elane, a pro-catabolic serine protease produced by macrophages. This results highlight the crosstalk between cartilage and surrounding macrophages and open up new therapeutic perspectives.

Acknowledgments:

This work has been supported by French Society of Rheumatology and ART Viggo association.

Disclosure of Interests:

None declared

Genotype by environment interaction in response to cold stress in a composite beef cattle breed

Extreme weather conditions such as cold stress influence the productivity and survivability of beef cattle raised on pasture. The objective of this study was to identify and evaluate the extent of the impact of genotype by environment interaction due to cold stress on birth weight (BW) and weaning weight (WW) in a composite beef cattle population. The effect of cold stress was modelled as the accumulation of total cold load (TCL) calculated using the Comprehensive Climate Index units, considering three TCL classes defined based on temperature: less than -5°C (TCL5), -15°C (TCL15) and -25°C (TCL25). A total of 4221 and 4217 records for BW and WW, respectively, were used from a composite beef cattle population (50% Red Angus, 25% Charolais and 25% Tarentaise) between 2002 and 2015. For both BW and WW, a univariate model (ignoring cold stress) and a reaction norm model were implemented. As cold load increased, the direct heritability slightly increased in both BW and WW for TCL5 class; however, this heritability remained consistent across the cold load of TCL25 class. In contrast, the maternal heritability of BW was constant with cold load increase in all TCL classes, although a slight increase of maternal heritability was observed for TCL5 and TCL15. The direct and maternal genetic correlation for BW and maternal genetic correlation for WW across different cold loads between all TCL classes were high (r > 0.99), whereas the lowest direct genetic correlations observed for WW were 0.88 for TCL5 and 0.85 for TCL15. The Spearman rank correlation between the estimated breeding value of top bulls (n = 79) using univariate and reaction norm models across TCL classes showed some re-ranking in direct and maternal effects for both BW and WW particularly for TCL5 and TCL15. In general, cold stress did not have a big impact on direct and maternal genetic effects of BW and WW.

Stratified primary care versus non-stratified care for musculoskeletal pain: findings from the STarT MSK feasibility and pilot cluster randomized controlled trial

BACKGROUND

Musculoskeletal (MSK) pain from the five most common presentations to primary care (back, neck, shoulder, knee or multi-site pain), where the majority of patients are managed, is a costly global health challenge. At present, first-line decision-making is based on clinical reasoning and stratified models of care have only been tested in patients with low back pain. We therefore, examined the feasibility of; a) a future definitive cluster randomised controlled trial (RCT), and b) General Practitioners (GPs) providing stratified care at the point-of-consultation for these five most common MSK pain presentations.

METHODS

The design was a pragmatic pilot, two parallel-arm (stratified versus non-stratified care), cluster RCT and the setting was 8 UK GP practices (4 intervention, 4 control) with randomisation (stratified by practice size) and blinding of trial statistician and outcome data-collectors. Participants were adult consulters with MSK pain without indicators of serious pathologies, urgent medical needs, or vulnerabilities. Potential participant records were tagged and individuals sent postal invitations using a GP point-of-consultation electronic medical record (EMR) template. The intervention was supported by the EMR template housing the Keele STarT MSK Tool (to stratify into low, medium and high-risk prognostic subgroups of persistent pain and disability) and recommended matched treatment options. Feasibility outcomes included exploration of recruitment and follow-up rates, selection bias, and GP intervention fidelity. To capture recommended outcomes including pain and function, participants completed an initial questionnaire, brief monthly questionnaire (postal or SMS), and 6-month follow-up questionnaire. An anonymised EMR audit described GP decision-making.

RESULTS

GPs screened 3063 patients (intervention = 1591, control = 1472), completed the EMR template with 1237 eligible patients (intervention = 513, control = 724) and 524 participants (42%) consented to data collection (intervention = 231, control = 293). Recruitment took 28 weeks (target 12 weeks) with > 90% follow-up retention (target > 75%). We detected no selection bias of concern and no harms identified. GP stratification tool fidelity failed to achieve a-priori success criteria, whilst fidelity to the matched treatments achieved "complete success".

CONCLUSIONS

A future definitive cluster RCT of stratified care for MSK pain is feasible and is underway, following key amendments including a clinician-completed version of the stratification tool and refinements to recommended matched treatments.

TRIAL REGISTRATION

Name of the registry: ISRCTN.

TRIAL REGISTRATION NUMBER

15366334. Date of registration: 06/04/2016.

Adherent-invasive Escherichia coli (AIEC): Cause or consequence of inflammation, dysbiosis, and rupture of cellular joints in patients with IBD?

There are many factors contributing to the development of gastrointestinal diseases, grouped into genetic, environmental, and lifestyle factors. In recent years attention has fallen on pathogens; in particular, Bacteroides fragilis, Fusobacterium nucleatum, Escherichia coli (E. coli) and Helicobacter pylori have been studied. Several points remain to be clarified, and above all, as regards the adherent-invasive E. coli strains of E. coli, one wonders if they are a cause or a consequence of the disease. In this review, we have tried to clarify some points by examining a series of recent publications regarding the involvement of the bacterium in the pathology, even if other studies are necessary.

Microcracks in subchondral bone plate is linked to less cartilage damage

OBJECTIVES

Osteoarthritis (OA) is a disease of the whole joint characterized by cartilage loss and subchondral bone remodeling. The role of microcracks in cartilage integrity and subchondral bone homeostasis is not fully understood. The main goal of this work was to evaluate microcrack density in both calcified cartilage and subchondral bone plate in relation to cartilage damage in humans and to better define the association of microcracks and osteocyte density in subchondral bone.

METHODS

We investigated 18 bone cores from cadaveric human knees that were stained with En-Bloc Basic Fuchsin. We quantified microcrack density, osteocyte density, cartilage surfaces and cartilage damage. The presence of microcracks was confirmed for each bone core by scanning electron microscopy. Finally, trabecular subchondral bone parameters were measured by micro-CT.

RESULTS

Microcracks were detected in both calcified cartilage and subchondral bone plate. The density of microcracks in both calcified cartilage (CC) and subchondral bone plate (SBP) was negatively correlated with cartilage damage (r = -0.45, p < 0.05). The presence of microcracks in SBP was associated with a lower histological OA score. Osteocytes formed a dendrite network that abruptly stopped at the border of calcified cartilage. Osteocyte density in subchondral bone plate was increased in the presence of microcracks in calcified cartilage.

CONCLUSIONS

Subchondral bone plate microcracks might be required for maintaining cartilage homeostasis. Microcracks in calcified cartilage may trigger osteocyte density in subchondral bone plate with subsequent regulation of subchondral bone remodeling to prevent cartilage damage.

Effects of curcumin and its adjuvant on TPC1 thyroid cell line

Previous studies have demonstrated that different curcumin extracts are able to influence cell metabolic activity vitality in human papillary thyroid carcinoma TPC-1 cells. We continued the study using the most effective extract and adding other nutraceuticals such as piperine and vitamin E, in order to define the possible role of these in modulating the genetic expression of cell markers and to understand the effectiveness in modulating the regression of cancer phenotype. Cells were treated with one extract of curcumin (Naturex^® Ultimate Botanical Benefits), with Piperine (Piper Longum, A.C.E.F.) and Vitamin E (Dry Vitamin E-Acetate 50% DC, BASF) alone and in combination, dissolved in the culture medium, for 48 h. Treatment with the different nutraceuticals is able to influence cell cycle regulators (cyclin D1, β-catenin, p21, p53) and activators or inhibitors of apoptosis (BAX, pro-caspase3, Bcl-2). They are able to influence cell cycle distribution and metabolic activity vitality. The inhibitory effect of curcumin, piperine and vitamin E on cell proliferation involves different markers, and in particular inhibits β-catenin, cyclinD1 and p53, making them candidates for a possible use in alternative therapies although further studies are needed.

Genomic prediction of continuous and binary fertility traits of females in a composite beef cattle breed

Reproduction efficiency is a major factor in the profitability of the beef cattle industry. Genomic selection (GS) is a promising tool that may improve the predictive accuracy and genetic gain of fertility traits. There is a wide range of traits used to measure fertility in dairy and beef cattle including continuous (days open), discrete (pregnancy status), and count (number of inseminations) responses. In this study, a joint analysis of age of puberty (AOP), age at first calving (AOC), and the heifer pregnancy status (HPS) was performed. Data used in this study consisted of records from 1,365 Composite Gene Combination (CGC; 50% Red Angus, 25% Charolais, 25% Tarentaise) first parity females born between 2002 and 2011. The pedigree file included 5,374 animals. A total of 3,902 animals were genotyped with different density SNP chips (3K to 50K SNP). Animals genotyped with low-density arrays were imputed to higher density (BovineSNP50 BeadChip) using FImpute. Data were analyzed using univariate and multivariate classical quantitative models (pedigree based) and univariate genomic approaches. For the latter, 3 different Bayesian methods (BayesA, BayesB, and BayesCπ) were implemented and compared. Estimates of heritabilities using univariate and multivariate analyses based on pedigree relationships ranged between 0.03 (for AOC) to 0.2 (AOP). Heritability of pregnancy status was 0.15 and 0.09 using the univariate and multivariate analyses, respectively. Genetic correlation between pregnancy status and the other 2 traits was low being 0.08 with age at puberty and -0.10 with age at first calving. Heritability estimates were slightly higher using genomic rather than average additive relationships. The accuracy of genomic prediction was similar across the 3 Bayesian methods with higher accuracies for age of puberty than the age at first calving likely due to the higher heritability of the former. The prediction of the binary pregnancy status measured using the area under the curve increased by 27% to 29% compared to a random classifier. Due to the small size of the data, all estimates have large posterior standard deviations and results should be interpreted with caution.

Genotype by environment interaction effects in genetic evaluation of preweaning gain for Line 1 Hereford cattle from Miles City, Montana

It has long been recognized that genotype × environment interaction potentially influences genetic evaluation of beef cattle. However, this recognition has largely been ignored in systems for national cattle evaluation. The objective of this investigation was to determine if direct and maternal genetic effects on preweaning gain would be reranked depending on an environmental gradient as determined by year effects. Data used were from the 76-yr selection experiment with the Line 1 Hereford cattle raised at Miles City, MT. The data comprised recorded phenotypes from 7,566 animals and an additional 1,862 ancestral records included in the pedigree. The presence of genotype × environment interaction was examined using reaction norms wherein year effects on preweaning gain were hypothesized to linearly influence the EBV. Estimates of heritability for direct and maternal effects, given the average environment, were 10 ± 2 and 26 ± 3%, respectively. In an environment that is characterized by the 5th (95th) percentile of the distribution of year effects, the corresponding estimates of heritability were 18 ± 3 (22 ± 3%) and 30 ± 3% (30 ± 3%), respectively. Rank correlations of direct and maternal EBV appropriate to the 5th and 95th percentiles of the year effects were 0.67 and 0.92, respectively. In the average environment, the genetic trends were 255 ± 1 g/yr for direct effects and 557 ± 3 g/yr for maternal effects. In the fifth percentile environment, the corresponding estimates of genetic trend were 271 ± 1 and 540 ± 3 g/yr, respectively, and in the 95th percentile environment, they were 236 ± 1 and 578 ± 3 g/yr, respectively. Linear genetic trends in environmental sensitivity were observed for both the direct (-8.06 × 10 ± 0.49 × 10) and maternal (8.72 × 10 ± 0.43 × 10) effects. Therefore, changing systems of national cattle evaluation to more fully account for potential genotype × environment interaction would improve the assessment of breeding stock, particularly for direct effects. Estimates of environmental sensitivity parameters could also facilitate identification of genetic limitations to production.

Animal models in OA: a means to explore bone

Cartilage damage which characterizes osteoarthritis is accompanied with bone lesions. Joint integrity results from the balance in the physiological interactions between bone and cartilage. Several local factors regulate physiological remodeling of cartilage, the disequilibrium of these leading to a higher cartilage catabolism. Several cytokines secreted by bone cells can induce chondrocyte differentiation which suggests their role in the dialogue between both cells. Several animal models of osteoarthritis have been developed in order to assess the mechanism of cartilage loss and chondrocyte functions that encompassed surgical, chemical, or genetic approaches. Indeed, the animal models are helpful to investigate the cartilage changes in relation to changes in bone remodeling. Accumulative in vivo evidence show that increased bone resorption occurs at early stage of the development of osteoarthritis. Inhibition of bone resorbing molecules prevents cartilage damage, confirming the role of bone factors in the cross talk between both tissues. Among these numerous molecules, some participate to the imbalance in cartilage homeostasis and in the pathophysiology of osteoarthritis. These local factors are potential candidates for new drug targets.

Radiographic hand osteoarthritis: patterns and associations with hand pain and function in a community-dwelling sample

OBJECTIVE

Patterns of radiographic osteoarthritis (ROA) of the hand are often examined by row, with the four joints of the thumb studied inconsistently. The objectives of this study were to determine relationships of ROA at different hand joints, use the findings to define radiographic sub-groups and investigate their associations with pain and function.

METHODS

Sixteen joints in each hand were scored for the presence of ROA in a community-dwelling cohort of adults, 50-years-and-over, with self-reported hand pain or problems. Principal components analysis (PCA) with varimax rotation was used to study patterns of ROA in the hand joints and identify distinct sub-groups. Differences in pain and function between these sub-groups were assessed using Australian/Canadian Osteoarthritis Index (AUSCAN), Grip Ability Test (GAT) and grip and pinch strength.

RESULTS

PCA was undertaken on data from 592 participants and identified four components: distal interphalangeal joints (DIPs), proximal interphalangeal joints (PIPs), metacarpophalangeal joints (MCPs), thumb joints. However, the left thumb interphalangeal (IP) joint cross-loaded with the PIP and thumb groups. On this basis, participants were categorised into four radiographic sub-groups: no osteoarthritis (OA), finger only OA, thumb only OA and combined thumb and finger OA. Statistically significant differences were found between the sub-groups for AUSCAN function, and in women alone for grip and pinch strength. Participants with combined thumb and finger OA had the worst scores.

CONCLUSION

Individual thumb joints can be clustered together as a joint group in ROA. Four radiographic sub-groups of hand OA can be distinguished. Pain and functional difficulties were highest in participants with both thumb and finger OA.

Does isolated patellofemoral osteoarthritis matter?

OBJECTIVES

To describe the structure-pain and structure-function associations in isolated patellofemoral osteoarthritis (PF OA).

DESIGN

Population-based study of 819 adults aged > or =50 years with knee pain. The severity of knee pain, stiffness and disability were measured using the Western Ontario and McMaster Osteoarthritis Index (WOMAC). Three radiographic views of the knee were obtained.

RESULTS

Isolated PF OA was mild in 142 participants and moderate/severe in 44. Mean WOMAC scores for pain, stiffness and function were associated with radiographic severity of PF OA (F(2,389)=4.7, P=0.01; F(2,392)=4.5, P=0.012 and F(2,392)=6.1, P=0.002, respectively, adjusted for age, gender, and body mass index (BMI)). Post-hoc tests demonstrated statistically significant differences for mean pain, stiffness and function score between those with mild PF OA and those with normal X-rays. In task-specific items there was evidence of a stepped response, the proportion of participants with moderate/severe/extreme pain or difficulty in performing everyday tasks increasing with the severity of PF OA. The strongest association was observed for pain going up and down stairs (age-gender-BMI adjusted odds ratio (OR) 3.0; 95% confidence interval (CI) 1.4,6.6. Functional tasks most strongly related to radiographic severity were: descending stairs (OR 3.2; (CI 1.5,6.5)), getting in/out of the bath (3.2; 1.5,6.6), getting in/out of a car (3.0; 1.4,6.1).

CONCLUSIONS

Mild isolated PF OA is significantly associated with symptoms of pain, stiffness and functional limitation. Further research on its recognition in clinical practice and the development of targeted treatments to prevent or slow progression are warranted.

An economic evaluation of three physiotherapy treatments for non-specific neck disorders alongside a randomized trial

OBJECTIVES

Cost-effectiveness and cost-utility analyses were conducted to compare advice and exercise plus manual therapy (MT) and advice and exercise plus pulsed shortwave diathermy (PSWD) with advice and exercise alone (A&E) in the treatment of non-specific neck disorders by experienced physiotherapists.

METHODS

Between July 2000 and June 2002, 350 participants with neck disorders from 15 physiotherapy departments were randomized to: A&E (n = 115); MT (n = 114) and PSWD (n = 121). Outcome and resource-use data were collected using physiotherapist case report forms and participant self-complete questionnaires. Outcome measures were the Northwick Park Neck Pain Questionnaire (NPQ) and EuroQoL EQ-5D [used to derive quality-adjusted-life-year (QALY) utility scores]. Two economic viewpoints were considered (health care and societal). Cost-effectiveness acceptability curves were used to assess the probabilities of the interventions being cost-effective at different willingness-to-pay threshold values.

RESULTS

Mean improvement in NPQ at 6 months was 11.5 in the A&E group, 10.2 in the MT group and 10.3 in the PSWD group; mean QALY scores were 0.362, 0.342 and 0.360, respectively. Mean health care costs were pound sterling105, pound sterling119 and pound sterling123 in the A&E, MT and PSWD groups, respectively. Mean societal costs were pound sterling373, pound sterling303 and pound sterling 338 in each group, respectively. Depending on the viewpoint and the outcome measure, A&E or MT were most likely to be the cost-effective interventions. PSWD was consistently the least cost-effective intervention.

CONCLUSIONS

The cost-effective intervention is likely to be A&E or MT, depending on the economic perspective and preferred outcome, but not PSWD.

Symptoms and radiographic osteoarthritis: not as discordant as they are made out to be?

OBJECTIVES

Joint pain and radiographic osteoarthritis are often discordant.

AIM

To investigate this issue more closely by studying the detailed nature of pain and disability, and how this relates to radiographic osteoarthritis.

METHODS

Population-based study of 819 adults aged >or=50 years with knee pain. The severity of knee pain, stiffness and disability was measured using a validated scale (the Western Ontario and McMaster Universities (WOMAC) Score) and pain persistence was recorded. Global severity was measured by the graded chronic pain scale. Three radiographic views of the knees were obtained-weight-bearing posteroanterior metatarsophalangeal, supine skyline and supine lateral.

RESULTS

745 participants with knee pain in the past 6 months were eligible (mean age 65 years, 338 men). Radiographic osteoarthritis was more common in those with a longer history and more persistent symptoms. A strong trend was found of radiographic osteoarthritis being more strongly associated with higher WOMAC scores for pain severity, stiffness and disability (adjusted odds ratio (95% confidence interval (CI)) for highest v lowest WOMAC category: 3.7 (2.0 to 6.7), 3.0 (2.0 to 4.6) and 2.8 (1.6 to 5.0), respectively). Those individual WOMAC items for pain and disability pertaining to weight-bearing mobility were the most strongly associated with radiographic osteoarthritis. Combining pain persistence and global severity, persistent severe pain was associated with a significant increase in the occurrence of radiographic osteoarthritis (2.6 (95% CI 1.5 to 4.7)).

CONCLUSIONS

A consistent association was found between severity of pain, stiffness and physical function and the presence of radiographic osteoarthritis. This study highlights the potential contribution of underlying joint disease to the degree of pain and disability.

Clinical classification criteria for knee osteoarthritis: performance in the general population and primary care

BACKGROUND

Doubts have been expressed about the performance of the American College of Rheumatology (ACR) clinical classification criteria for osteoarthritis when applied in the general population.

OBJECTIVE

To investigate whether the distribution of population subgroups and underlying disease severity might explain the performance of these criteria in the population setting.

METHODS

Population-based cross-sectional study. 819 adults aged > or = 50 years reporting knee pain in the last 12 months were clinically assessed by research therapists using standardised protocols and blinded to radiographic status. All participants underwent plain radiography of the knees, scored by a single reader blinded to clinical status. The relationship between fulfilling the ACR clinical classification criteria for knee osteoarthritis and the presence of symptomatic radiographic knee osteoarthritis was summarised for the sample as a whole and within subgroups.

RESULTS

Radiographic osteoarthritis was present in 539 participants (68%) and symptomatic radiographic knee osteoarthritis in 259 (33%). 238 participants (30%) fulfilled the ACR clinical criteria for knee osteoarthritis. Agreement between the ACR clinical criteria and symptomatic radiographic knee osteoarthritis was low (sensitivity 41%; specificity 75%; positive predictive value 44%; negative predictive value 72%). Sensitivity and specificity did not vary markedly between population subgroups, although they were influenced by the underlying severity of radiographic osteoarthritis.

CONCLUSION

The ACR clinical criteria seem to reflect later signs in advanced disease. Other approaches may be needed to identify early, mild osteoarthritis in the general population and primary care.

End tidal carbon dioxide as a predictor of the arterial PCO2 in the emergency department setting

OBJECTIVES

Patients arriving in the emergency department (ED) need rapid and reliable evaluation of their respiratory status. Mainstream end tidal carbon dioxide (ETCO(2)) is one of the methods used for this purpose during general anaesthesia of intubated patients in the operating theatre. Sidestream ETCO(2) (SSETCO(2)) might be a non-invasive, rapid, and reliable predictor of arterial Pco(2) in non-intubated patients in respiratory distress. The aim of this study was to verify whether SSETCO(2) can accurately predict the arterial Pco(2) and to detect variables that may affect this correlation.

METHODS

A prospective semi-blind study. The participants were 73 patients (47 men, 26 women) referred to the ED for respiratory distress. Arterial blood gas pressures and SSETCO(2) measurements were performed and recorded for all patients. Other parameters recorded were: age; body temperature; respiratory rate; blood pressure; pulse rate; and medical diagnosis.

RESULTS

A significant correlation was found between SSETCO(2) and arterial Pco(2) (r = 0.792). Compared with the correlation curve of the whole group, age under 50 years deflected the correlation curve to the left, while temperature above 37.6 degrees C deflected it to the right. The rest of the parameters had no clear influence on the SSETCO(2)/Pco(2) correlation curve.

CONCLUSIONS

There is a good correlation between SSETCO(2) and arterial Pco(2) in the ED setting. Young age may increase the arterial Pco(2)/SSETCO(2) gradient while raised temperature may decrease this gradient. Further studies are needed to confirm these findings in the normal healthy population.

Evidence-based recommendations for the role of exercise in the management of osteoarthritis of the hip or knee--the MOVE consensus

OBJECTIVES

Exercise is an effective and commonly prescribed intervention for lower limb osteoarthritis (OA). Many unanswered questions remain, however, concerning the practical delivery of exercise therapy. We have produced evidence-based recommendations to guide health-care practitioners.

METHODS

A multidisciplinary guideline development group was formed from representatives of professional bodies to which OA is of relevance and other interested parties. Each participant contributed up to 10 propositions describing key clinical points regarding exercise therapy for OA of the hip or knee. Ten final recommendations were agreed by the Delphi technique. The research evidence for each was determined. A literature search was undertaken in the Medline, PubMed, EMBASE, PEDro, CINAHL and Cochrane databases. The methodological quality of each retrieved publication was assessed. Outcome data were abstracted and effect sizes calculated. The evidence for each recommendation was assessed and expert consensus highlighted by the allocation of two categories: (1) strength of evidence and (2) strength of recommendation.

RESULTS

The first round of the Delphi process produced 123 propositions. This was reduced to 10 after four rounds. These related to aerobic and strengthening exercise, group versus home exercise, adherence, contraindications and predictors of response. The literature search identified 910 articles; 57 intervention trials relating to knee OA, 9 to hip OA and 73 to adherence. The evidence to support each proposition is presented.

CONCLUSION

These are the first recommendations for exercise in hip and knee OA to clearly differentiate research evidence and expert opinion. Gaps in the literature are identified and issues requiring further study highlighted.

Development of the Knee Standardized Clinical Interview: a research tool for studying the primary care clinical epidemiology of knee problems in older adults

OBJECTIVE

To develop a standardized clinical interview, incorporating the perspectives of general practitioners (GPs) and rheumatologists, for primary care clinical epidemiological studies of adults aged 50 yr and over with knee problems.

METHODS

Two parallel, consensus development studies using a modified nominal group technique involving GPs (n=5) and consultant rheumatologists (n=4) from North Staffordshire with reference panels of GPs (n=28) and rheumatologists (n=11) from selected centres in Great Britain, respectively. A single standardized clinical interview was formed using the clinical history questions identified in the consensus development studies and its feasibility was tested in a small sample of patients.

RESULTS

In the GP consensus development study, 115 clinical history questions were identified, of which 71 were of agreed importance following postal rating, face-to-face discussion and re-rating. In the rheumatologist study, 158 questions were identified, of which 47 were of agreed importance. There was considerable overlap in the clinical history questions independently developed by the two studies. A single standardized clinical interview containing 74 questions was formed. It contained questions on the history, onset and recent course of the complaint; nature, location and severity of current knee symptoms; impact of knee problem; past history of knee problems; family history; comorbidity; previous/current investigations and treatment; ideas, concerns and expectations. In preliminary testing it took 20-45 min to conduct and was comprehensible to patients.

CONCLUSIONS

A research tool-the Knee Standardized Clinical Interview (KNE-SCI)-has been formed from consensus development studies involving GPs and rheumatologists. In preliminary testing, it is comprehensible to patients, and forms a coherent clinical interview for research data collection. However, further evaluation is required to determine its accuracy and reliability and its usefulness for clinical epidemiological research.

Clinical assessment of the osteoarthritis patient

It is becoming apparent that the disease process of osteoarthritis should be regarded separately from the clinical syndrome of joint pain, use-related stiffness and disability. The latter may best be approached as a chronic regional pain disorder that requires attention to physical, psychological and social factors as well as those related to the disease process. This chapter sets out to look at some of the practical implications of taking this view for the clinical assessment. Starting with the syndrome of hip, knee or hand pain in older adults in the community, we consider what leads people to consult, what the important features to assess might be, the role of imaging in the clinical assessment of osteoarthritis, and finally how a management plan could be formulated. The usefulness of assessing clinical osteoarthritis as a regional pain disorder is uncertain. Even if this were demonstrated, the concept of osteoarthritis as a structural disease should be retained as an integral part.

Fibroblast growth factor-2 (FGF-2) increases N-cadherin expression through protein kinase C and Src-kinase pathways in human calvaria osteoblasts

Fibroblast growth factors (FGFs) are important factors regulating osteogenesis. However, the early mechanisms and signaling pathways involved in FGF actions in osteoblasts are unknown. We investigated the effects of FGF-2 on cell-cell adhesion and cadherin expression and the underlying signaling pathways in immortalized human neonatal calvaria (IHNC) cells. These cells express E- and N-cadherins, as shown by immunocytochemical and Western blot analyses. rhFGF-2 increased cell-cell adhesion at 24-72 h, as measured in a cell aggregation assay, and this effect was blocked by specific neutralizing anti-N-cadherin, but not anti-E-cadherin antibodies. Accordingly, ELISA and Western blot analyses showed that rhFGF-2 (10-100 ng/ml) dose dependently increased N-cadherin but not E-cadherin protein levels. RT-PCR analysis showed that rhFGF-2 transiently increased N-cadherin mRNA levels in IHNC cells. The RNA polymerase II inhibitor 5,6-dichloro-1-beta-D-ribofuranosyl benzimidazole prevented the rhFGF-2-induced up-regulation of N-cadherin mRNA, suggesting that transcription is necessary for this effect. Analysis of signaling molecules showed evidence that PLCgamma-PKC, Src, Erk 1/2 and p38 MAPK pathways are activated by rhFGF-2 in IHNC cells. The selective PKC inhibitors calphostin C, Ro-31-8220, Gö6976 and Gö6983 abrogated the stimulatory effect of rhFGF-2 on N-cadherin mRNA levels. The src-family tyrosine kinase inhibitor PP1 also blocked rhFGF-2-promoted N-cadherin expression. In contrast, the p38 MAP kinase inhibitor SB 203580 or the MEK inhibitor PD98059 had no effect on rhFGF-2-induced N-cadherin mRNA levels. Our data indicate that FGF-2 increases N-cadherin expression and function in human calvaria osteoblasts via activation of PKC and src-kinase pathways. This study identifies N-cadherin as a previously unrecognized target gene for FGF-2 signaling pathway that regulates cell-cell adhesion in human osteoblasts.

Quality assurance of nurse triage: consistency of results over three years

The study objective was to evaluate the capability and the consistency of the triage nurse to categorize correctly emergency patients and its impact on the waiting time for physician examination over a period of 3 years. The study was performed at the emergency department of the Barzilai Medical Center, Ashkelon, Israel. A retrospective review of the medical records was performed. All patients who were examined by a triage nurse during 2 randomly chosen consecutive weeks during the years 1995 and 1998 participated. All the medical records were reviewed by the authors and the following information was extracted from the medical records: nurse triage category, time of initial evaluation by a triage nurse, duration of employment of the nurse in the ED, and her experience as a triage nurse, time of initial examination by a physician, the total length of stay in the ED, the history taken by the triage nurse and the physician, and the physician's urgency category. Patient in urgency category 1 is a patient whose condition may deteriorate if not examined within 1 hour; patient in category 2 is a patient whose condition may deteriorate if not examined within 2 hours; category 3 is all the rest. Any deterioration and or delay of treatment of the patients were also recorded. Data concerning patients with an initial complaint of chest pain were extracted separately. The data were analyzed using the SPSS software and the results were tested by the student t test and chi square test. Interobserver agreement was measured using the kappa value. A total of 2,886 completely full medical records were reviewed by the authors: 1,310 records from period I (1995) and 1576 from period II (1998). Of the patients 92% and 88.2% were classified by the triage nurse as category 3 in periods I and II respectively, 7% and 9.8% as category 2, and 1% and 2% as category 1 respectively. Full agreement of triage category between nurse and physician was found in 90.5% of the cases in period I and 93% in period II (kappa = 0.90 and kappa = 0.93 respectively). In period I, 70% of the patients in category 1 were examined by a physician in 1 hour versus 100% in period II. Almost all the patients in category 2 were examined within 2 hours (98%, 97%), and 98% of those in category 3 were examined within 3 hours. The average waiting time for physician examination in category 1 patients dropped from 43.1 minutes in period I to 18.2 minutes in period II. The average waiting time for the triage nurse was 9 minutes in period I, and 7.42 minutes in period II. The average length of stay in the ED in period I was 1 hour and 24 minutes and 1 hour and 30 minutes in period II. Of the anamneses taken by the triage nurse 91.8% were fully identical with the physicians' anamneses, but in period II this percentage jumped to 98%. Patients with chest pain were categorized correctly by the triage nurse in 76.8% of the cases in period I and 72.4% in period II, with an overtriage of 18.6% and 20.7% respectively (kappa = 0.75, kappa = 0.70 respectively). In our study, nurse triage was safe and effective in classifying patients to urgency categories. The results are consistent and even improved over a 3-year period. The rates of incorrect classification, deterioration, and delay of treatment of patients because of incorrect triage are very low. Most of the patients were examined by the physician within the expected time. Triage nurse predicted correctly the urgency category of patients with chest in most of the cases and the rate of missing acute coronary events was very low.

Rare Jatropha multifida intoxication in two children

Two children were admitted to the Emergency Department (ED) after ingesting a large amount of fruit of a plant identified as Jatropha multifida. They were mildly obtunded, had intractable vomiting, and seemed dehydrated. Intravenous fluid replacement and urine alkalinization were initiated. After stabilization, their 5-day hospital stays were uneventful except for a subclinical rise of liver enzymes. Jatropha species contain the toxalbumin ricin, which causes severe vomiting and diarrhea, dehydration, shock, and renal and hepatic impairment. Ricin also has cardiotoxic and hemolytic effects and several deaths have been documented. Children are attracted by the shape and the color of the Jatropha fruits. Mortality can be prevented by immediate fluid and electrolyte replacement.

Suicide by ingestion of a CCA wood preservative

Chromated-copper-arsenate (CCA) is a compound used worldwide for wood preservation. Occupational hazards from chronic exposure to CCA are well known, but acute ingestion of CCA wood preservative is very rare. We describe a case of suicide by ingestion of a CCA wood preservative. A 33-year-old man attempted suicide by ingesting an unknown liquid, later identified as a CCA wood preservative, 75 min before his arrival in the emergency department. He was in severe respiratory distress, drooling, tachycardic, and hypotensive. There was an orange color on the palms of both hands. Severe, green colored burns of the buccal mucosa were observed. He was intubated shortly after arrival. The larynx was edematous, but a 7-mm endotracheal tube was successfully introduced. Blood tests revealed partially compensated metabolic acidosis. The patient deteriorated rapidly; the systolic blood pressure dropped to 70 mmHg, and he passed bloody diarrhea. He developed multiple premature atrial contractions and supraventricular tachycardia, and later in the intensive care unit, refractory ventricular tachycardia and ventricular fibrillation. The patient was declared dead 212 h after his arrival. Unfortunately, postmortem blood levels of heavy metals and autopsy were not performed because of refusal by the family for religious reasons.

Prior antihypertensive treatment and admission blood pressure correlated with clinical outcome and early morning presentation in hypertensive ischaemic stroke patients

Blood pressure (BP) reduction of 5-6 mm Hg reduces the relative risk of stroke by 30-40%. This effect does not appear to depend on the antihypertensive agent used to bring about the required reduction in BP. Patients with acute ischaemic stroke often exhibit an elevated BP. These patients, who previously suffered from hypertension, have significantly higher levels of BP readings on admission with increased incidence of stroke immediately after arising. The aim of this study was to compare antihypertensive agents, especially short and long acting drugs with the measurement of BP on admission, the time of the ischaemic stroke and its clinical severity. This was studied retrospectively in 109 patients (55 females and 54 males). The mean age was 69.7 +/- 10.4 years. All the patients admitted between 1 July 1996 and 30 June 1997 for ischaemic stroke as established by brain CT scan, were studied. Of the stroke subjects not treated or treated with short acting calcium blockers, 40.8% and 44.4% of them respectively appeared to have an ischaemic stroke in the early morning hours in contrast to 20% of those treated with long acting calcium blockers (P < 0.05). The last group of patients also experienced less clinical severity. These results emphasise the need for proper 24-h control of BP and by comparison to other antihypertensive agents, the long acting calcium blockers with these subjects may prevent a sudden early morning rise in BP, which is instrumental in stroke prevention.