Risk factors for exertional heat illness in Thoroughbred racehorses in flat races in Japan (2005-2016)

BACKGROUND

Exertional heat illness (EHI) is recognised in horses, but few reports have investigated its risk factors.

OBJECTIVES

To identify risk factors for EHI in racehorses participating in flat races in Japan.

STUDY DESIGN

Descriptive epidemiology and retrospective unmatched case-control study.

METHODS

Between 2005 and 2016, veterinary records of horses diagnosed with EHI after flat races were reviewed retrospectively and data of the months from April to September were used for a case-control study. For each case, three control horses were randomly selected from starts between April and September. Race records of horses and estimated wet-bulb globe temperature (WBGT) indexes at the local meteorological observatory closest to the racecourse were investigated. To identify risk factors for EHI, univariable and multivariable logistic regression analysis was used.

RESULTS

Of 194 cases during the study period, 188 cases occurred between April and September. The highest incidence risk was in July (1.1 cases per 1000 starts, 95% confidence interval 0.84-1.45). In the final multivariable model, WBGT index, sex, race distance, age and bodyweight were associated with EHI. When WBGT index exceeded 28°C, the risk of EHI was considerably higher than <20°C (OR 28.5, 14.2-62.4, P<0.001). Compared with uncastrated males, geldings (OR 4.9, 1.8-13.3, p = 0.002) and females (OR 2.4, 1.5-3.7, P<0.001) were at high risk of EHI (P<0.01). Furthermore, races of >1600 m (OR 1.8, 1.2-2.8, P = 0.002), 4-year-old (OR 3.5, 1.6-7.9, P = 0.002) and ≥5-year-old (OR 3.9, 1.8-9.2, P = 0.001) horses and horses with low bodyweight (OR per 20 kg, 0.8, 0.7-1.0, P = 0.02) were associated with increased risk of EHI.

MAIN LIMITATIONS

The median straight-line distance between the racecourse and the local meteorological observatory was 14.2 km (range, 1.1-28.3 km). There was a lack of objective criteria of EHI due to the retrospective nature of the study.

CONCLUSIONS

We identified specific risk factors for EHI in racehorses. These results may be useful to the equine industry for reducing EHI occurrence in racehorses.

P684Long-term outcomes in patients with cancer undergoing percutaneous coronary intervention: analysis from a Japan multicenter registry

Background

Cancer and cardiovascular disease (CVD) is the most common cause of death in developed countries, and substantial overlap exist in their medical care. However, the detailed and updated information on outcome of cancer patients with cardiovascular disease (CVD), particularly in clinically significant coronary artery disease (CAD) remain unknown.

Purpose

We sought to describe the prevalence and long-term outcomes of cancer patients undergoing percutaneous coronary intervention (PCI), which has become a coronerstone in the management of CVD.

Methods

Patient data extracted from a regional prospectiveprocedure-based multicenter registry for PCI was analyzed. A total of 4,455 patients who underwent PCI at 15 hospitals within metropolitan Tokyo from September 2008 to 2012 were followed for 2 years. “Active” cancer patient was defined as having a history of cancer not cured or in remission. We analyzed in acute and stable presentation.The occurrence of clinical outcomes was assessed via Kaplan-Meier survival curve, and Cox-regression hazard model to adjust for known clinical predictors.

Results

Within the studied patients, 173 (3.9%) had a concomitant “active” cancer at the time of intervention. There was a significant difference between the patients with and without active cancer in each situation. In stable presentation, cancer group were older, lower BMI, frequently had silent ischemia, COPD and cerebrovascular/peripheral disease, and less often had dyslipidemia compared with non-cancer group. In acute presentation, cancer group were older, frequently had COPD, CKD, peripheral disease and history of HF compared with non-cancer group. The prescription rate of RAAS inhibitor was lower in the cancer group than in the non-cancer group in acute presentation. Notably, in both acute and stable presentation, these patients had significantly higher risk of all-cause mortality (HR 8.01: 95%, p<0.001 and HR5.53: 95%, p<0.001, respectively), and they were also at higher risk of major cardo- and cerebrovascular events (MACCE; HR2.38, p<0.001, HR2.33, p=0.001), when referenced to non-cancer patients after 2 year of follow-up.

Conclusion

Cancer patient was present in 3.9% of all PCI patients and was strongly associated with both non-cardiac and cardiac adverse events.

P3355Stress-induced left ventricular dyssynchrony predicts future cardiac events in patients with known or suspected coronary artery disease

Background

Prognostic value of stress induced left ventricular (LV) dyssynchrony has not been fully understood.

The aim of this study was to evaluate the possible impact between cardiovascular events and stress induced worsening LV dyssynchrony.

Methods and results

One hundred and eighty consecutive subjects with known or suspected coronary artery disease (CAD) (142 men, mean age 68±12 years) underwent both gated myocardial single photon emission computed tomography (SPECT) with 99mTc-sestamibi or tetrofosmin according to a standard same day stress-rest protocol and coronary angiography or coronary computed tomography. The summed difference score (SDS) was calculated in every subjects. LV ejection fraction (EF) and phase Entropy at after stress and rest were determined by cardioREPO software. We determined %ΔEntropy = (stress Entropy - rest Entropy)/rest Entropy x100, as an indicator of stress-induced LV dyssynchrony. In the study population, the mean SDS was 2.7±3.9 and LVEF was 58±16%, stress and rest Entropy were 0.62±0.15 and 0.57±0.13, respectively.

%ΔEntropy was higher in patients with CAD than in those without CAD (3.3±11.5 vs. 10.2±15.0, respectively). Moreover, there was a strict correlation between the presence of CAD and %ΔEntropy, indicator of stress induced LV dyssynchrony (non-CAD vs. CAD and/or 1 vessel disease vs. multivessel disease: 4.3±12.5 vs. 8.8±15.6 vs. 12.7±14.3, respectively. p<0.05)

We examined all study subjects and they were divided into 2 groups by cut off value of the %ΔEntropy constructed with receiver operating characteristic curve (=15.4). Kaplan-Meier analysis revealed that future cardiovascular event rate was significantly higher in %ΔEntropy >15.4 group (20/57) than in %ΔEntropy <15.4 group (24/123) (Log-rank p<0.01). On the other hand, summed stress score and SDS were no significant differences between 2 groups.

However, SDS was higher in patients with future cardiovascular event than in those without cardiovascular event (4.4±5.4 vs. 2.2±3.2, respectively. p=0.001).

Conclusion

In patients with known or suspected CAD, stress-induced worsening LV dyssynchrony may predict the presence of CAD and future cardiac events.

Acknowledgement/Funding

None

P4341Sex differences in the U-shaped relationship between physical activity and cardiovascular mortality in the general population

Background

The beneficial effect of moderate physical activity on morbidity and mortality has been observed in the general population. However, sex differences in the impact of physical activity on cardiovascular mortality remain unclear. The aim of this study was to investigate the relationship between physical activity and cardiovascular mortality in the general population.

Methods

This longitudinal cohort study included 1,826 apparently healthy subjects who participated in a community-based health checkup.

Results

There were 97 deaths, including 31 cardiovascular deaths during 10-year follow-up. Subjects were divided into 4 groups based on the quartiles of physical activity (low, mild, moderate and high). There was a U-shaped relationship between physical activity and cardiovascular mortality in male subjects, but not in female subjects. Kaplan-Meier analysis demonstrated that high and low physical activity groups showed higher cardiovascular mortality compared with mild and moderate physical activity groups in male subjects. Cox proportional hazard analysis revealed that low and high physical activities were associated with cardiovascular mortality (hazard ratio 3.59 and 5.11, respectively) in male subjects. In contrast, physical activity was not associated with cardiovascular mortality in female subjects.

Conclusion

We identified a U-shaped relationship between the amount of physical activity and cardiovascular mortality in male subjects, but not in female subjects.

P3467Tricuspid annular isovolumic acceleration is more useful for the assessment of right ventricular systolic function in patients after repair of tetralogy of Fallot with pulmonary regurgitation

Introduction

The detrimental impact of pulmonary regurgitation (PR) on right ventricular (RV) function of patients after repair of tetralogy of Fallot (TOF) is recognized. Although tricuspid annular isovolumic acceleration (IVA) is useful for the evaluation of RV function, it requires complicated measurement. Tricuspid annular plane systolic excursion (TAPSE) is measured easily and has also been validated as a marker of RV systolic function.

Hypothesis

We assessed the hypothesis that IVA has advantage to the stratification of the detrimental impact of PR on RV systolic function after TOF repair compared with TAPSE.

Methods

We prospectively examined patients after TOF repair. Patients <1 year after the repair, those with the history of sustained arrhythmia and those who required concomitant tricuspid and/or pulmonary valve surgery were excluded from the study. IVA was measured by dividing the myocardial velocity during isovolumic contraction by the time interval from the onset of the myocardial velocity during the isovolumic contraction to the time at the peak velocity of this wave. TAPSE was measured using M-mode echocardiography with the M-line passing through the lateral annulus of tricuspid valve in the apical 4-chamber plane. PR jets were evaluated in the parasternal short-axis plane. PR degree was assessed by the number of correspondence to the following conditions; 1) diastolic flow reversal in the main pulmonary artery, 2) diastolic flow reversal in the branch pulmonary arteries, 3) pressure half-time of PR signal <100 msec and 4) the ratio of the duration of the PR signal to the total duration of diastole <0.77. PR degree was graded from 0 to 4.

Results

Twenty-two patients were enrolled to the study. Age, female, period after the TOF repair and body height of the patients were 11±6 years, 55%, 9±5 years and 137±28 cm, respectively. In all the patients, IVA and TAPSE were 160±27 cm/sec2 and 12±2 mm, respectively. PR degrees were graded as 2, 3 and 4 in 4, 14 and 4 patients, respectively. By the Kruskal-Wallis test, only IVA showed a significant difference among the 3 PR degrees.

Conclusion

In conclusion, IVA can be a useful index for the stratification of RV function in patients after TOF repair with various degrees of PR.

5945Single nucleotide polymorphisms of PAR2 gene is associated with subclinical myocardial damage in the general population

Introduction

The protease activated receptor (PAR) 2 is a G protein-coupled receptor and expressed in cardiomyocytes, vascular cells, and leukocytes. Experimental studies demonstrated that PAR2 signaling is associated with adverse cardiac remodeling, heart failure, vascular inflammation and atherosclerosis. Recently, we and others demonstrated that subclinical myocardial damage is associated with cardiovascular mortality in general population. However, the impact of single nucleotide polymorphisms (SNPs) of PAR2 gene on subclinical myocardial damage in general population is unclear.

Purpose

The aim of this study was to investigate whether SNPs of PAR2 gene is associated with subclinical myocardial damage in general population.

Methods

The present study included 2,926 apparently healthy subjects (aged ≥40) who participated in a community-based health checkup. We investigated 639 SNPs and measured serum heart-type fatty acid binding protein (H-FABP) as markers of subclinical myocardial damage.

Results

We found the association of SNPs rs616235 within a PAR2 gene with subclinical myocardial damage. The homozygous A-allele (AA), heterozygous (AG), and homozygous G-allele (GG) carriers of rs616235 were identified in 2084 (71%), 791 (27%), and 51 (2%) subjects, respectively. The prevalence rates of subclinical myocardial damage were 29% in AA carriers, 23% in AG carriers, and 18% in GG carriers. Multivariate logistic analysis showed that the homozygous (AA) of rs616235 was independently associated with subclinical myocardial damage (odds ratio: 1.330, 95% confidence interval: 1.077–1.641, P=0.0080) after adjustment for conventional cardiovascular risk factors.

Conclusions

Genetic variant of PAR2 gene was independently associated with subclinical myocardial damage in the general population.

P5607Clinical characteristics and treatment strategy for acute aortic dissection in Tokyo Acute Aortic Disease Super-Network System

Introduction

Acute aortic dissection (AAD) is one of the most fatal cardiovascular diseases. The prevalence of AAD is reported to be low. The clinical data of AAD from representative cardiovascular centers are not enough to show the whole range of clinical feature of AAD. We have to know the exact prevalence and clinical pictures of AAD under the new system, the Tokyo AAD Super-Network System (TAAD-SNS), for strategy of emergency transport and treatment of AAD which would cover the entire metropolitan area of Tokyo. TAAD-SNS started in 2011, and after slight modification, the new system of AAD re-started in 2013. The aim of this study is to elucidate the whole range of clinical characteristics and recent trends of treatment of AAD.

Methods

Out of 73 hospitals included in Tokyo CCU Network system, 41 hospitals are chosen for TAAD-SNS. These hospitals provide around-the-clock surgery. In this system, the availability of surgical division is monitored in real time. All of the patients suspected of AAD are transferred directly or from primary care hospital to the hospitals of TAAD-SNS.

Results

After exclusion of 237 patients with cardiopulmonary arrest on arrival, 4877 consecutive patients (2923 male, mean age of 69±14 y/o) were admitted to the hospitals with diagnosis of AAD from 2013 to 2016. Prevalence of AAD in Tokyo was about 10 patients per 100,000 populations in every year. After exclusion of 37 patients undetermined into type A or B, 4840 patients (2694 with type A and 2146 with type B) were analyzed. Among the type A patients, 1752 (65%) were classified into type of patent false lumen (classic-type), 721 (27%) of closed false lumen (intramural hematoma: IMH-type), and 221 (8%) were undetermined. Among the type B, 880 (41%) were classified into classic-type, 1129 (53%) of IMH-type, and 137 (6%) were undetermined. Both among type A and B, mean ages were younger in classic-type than in IMH-type (type A: 66±14 vs. 73±12 y/o, p<0.05; type B: 64±15 vs. 72±12 y/o, p<0.05). Prevalence of male population and risk factor of hypertension was higher in type B than in type A both among classic-type and IMH-type. Systolic blood pressure at the emergency room was lower in type A than in type B among both classic-type and IMH-type (classic-type: 124±34 vs. 161±38 mmHg, IMH-type: 130±51 vs. 163±56 mmHg). In-hospital mortality of surgical treatment for type A classic-type and type A IMH-type, conservative strategy for type B classic-type and type B IMH-type was 9.6%, 4.2%, 3.1% and 1.7%, respectively. Stentgraft implantation for type B AAD started and shows a favorable in-hospital mortality compared to the operative treatment (Stentgraft vs. surgery in type B classic-type: 7.8% vs. 6.5%, in type B IMH-type: 10.7% vs. 11.8%, respectively).

Conclusion

Our study showed that prevalence of AAD was 2–3 times higher than previous reports. We should consider to choose the treatment strategy according to the type of AAD, A or B, classic-type or IMH-type.

Acknowledgement/Funding

Tokyo Metropolitan government

P6209Relationship between skin autofluorescence levels and clinical outcomes in heart failure patients undergoing cardiac rehabilitation

Background

Advanced glycation end-products, indicated by skin autofluorescence (SAF) levels, could be prognostic predictors of all-cause and cardiovascular mortality in patients with diabetes mellitus (DM) and renal disease. However, the clinical usefulness of SAF levels in patients with heart failure (HF) who underwent cardiac rehabilitation (CR) remains unclear.

Purpose

The purpose of this study was to investigate the prognostic value of SAF levels in patients with HF who underwent CR.

Methods

This study enrolled 204 consecutive patients with HF who had undergone CR at our university hospital between November 2015 and October 2017. Clinical characteristics and anthropometric data were collected at the beginning of CR. SAF levels were noninvasively measured with an autofluorescence reader. The major adverse cardiovascular event (MACE) was a composite of all-cause mortality and unplanned hospitalization for HF. Follow-up data concerning primary endpoints were collected until November 2018.

Results

Patients' mean age was 68.1 years, and 61% were males. Patients were divided into two groups according to the median SAF levels (high and low SAF groups). Patients in the high SAF group were significantly older, had a higher prevalence of chronic kidney disease, and histories of coronary artery bypass surgery; however, there were no significant between-group differences in sex, prevalence of DM, left ventricular ejection fraction, and physical function. During a median follow-up period of 623 days, 25 patients experienced all-cause mortality and 34 were hospitalized for HF. Kaplan–Meier analysis showed that patients in the high SAF group had a higher incidence of MACE (log-rank P<0.05), whereas when patients were divided into two groups according to the median hemoglobin A1c level, no significant between-group difference was observed for the incidence of MACE (Figure). After adjusting for confounding factors, Cox regression multivariate analysis revealed that SAF levels were independently associated with the incidence of MACE (hazard ratio: 1.74, 95% confidence interval: 1.12–2.65, P<0.05).

Figure 1

Conclusion

SAF levels were significantly associated with the incidence of MACE in patients with HF and may be useful for risk stratification in patients with HF who undergo CR.

P6298Pericardial transplantation of adipose-derived stromal cells with self-assembling peptides scaffold prevents cardiac remodeling after myocardial infarction in mice

Introduction and purpose

Cardiac cell therapy to patients with heart failure after myocardial infarction (MI), has shown little improvement in cardiac function. The rate of engraftment after cell transplantation (TX) to the ischemic heart is low because of the leakage of transplanted cells without scaffold, the friction between the graft and thorax, and poor vascularization to the graft. We created a novel TX method (Figure 1) to transplant adipose-derived stromal cells (ASCs) with scaffold into the pericardial space where the pericardium protected the graft. We evaluated the therapeutic efficacy of pericardial TX of ASCs on the cardiac function and remodeling after MI.

Methods

We isolated ASCs from the brown adipose tissue of donor mice (C57BL6-Tg (CAG-EGFP), five weeks). ASCs increased and differentiated into spontaneously beating myocytes, endothelial cells, and pericytes three weeks after ex vivo culture. Cells were trypsinized and mixed with self-assembling peptides scaffold. Each graft (100μl gel scaffold) had 1×106 ASCs. To make recipient MI mice (C57BL6, 12 weeks), we ligated the left coronary artery through small chest incision without cutting rib bone to avoid postoperative adhesions. We confirmed the deterioration of cardiac function by echocardiography (n=21) and MRI (n=4) three weeks after MI. Then, recipient MI mice had TX (syngeneic, no immunosuppression). We opened the pericardium and transplanted the graft into the pericardial space. By suturing the pericardium, the graft was fixed on the MI scar area (Figure 1). We labeled donor cells with GFP and the scaffold with biotin. We evaluated cardiac function of TX group (n=10) and control group (MI with sham TX, n=11) by echocardiography.

Results

In the scaffold, donor cells increased three days to two weeks after TX, and slightly decreased four weeks after TX. The graft thickness was 0.9±0.2mm (two weeks after TX) and 0.7±0.2mm (four weeks after TX). There were many vWF positive vessels in the scaffold and some of which were GFP positive. Echocardiography showed that left ventricular diastolic dimension (LVDd) of TX group, did not increase four weeks after TX (ΔLVDd = −0.02mm, P=0.80). While, LVDd of control group significantly increased (ΔLVDd = +0.23mm, P=0.02) due to cardiac remodeling after MI. MRI confirmed the increase in left ventricular wall thickness in the MI scar area up to 4 weeks in TX group (n=2).

Conclusions

Pericardial transplantation of ASCs prevents cardiac remodeling. Its beneficial effect might be mediated by improved rate of engraftment, neovascularization, and increased ventricular wall thickness in the MI scar area.

Acknowledgement/Funding

Grants-in-Aid for Scientific Research

Active transport of glucose across the jejunal epithelium decreases with age in broiler chickens

Intestinal glucose absorption varies with growth; however, the dynamics of these variations has not been yet fully elucidated in broiler chickens. The present study aimed to compare jejunal glucose uptake and maltose digestion in broilers of 2 different ages, i.e., 1- vs. 5 wk old. Oral D-maltose gavage, everted sac, and Ussing chamber experiments were carried out to investigate intestinal glucose absorption and mRNA expression of glucose-transport-related genes as well as jejunal maltase activity. Upon gavage, glucose concentrations peaked at 10 min post-administration in 1-wk-old chicks, while they peaked at 40 min in 5-wk-old chickens. Glucose concentrations at 10 min were significantly higher in the 1-wk-old chicks (P = 0.010). Using the everted sacs experimental setup, 5 intestinal regions i.e., duodenum, proximal jejunum, distal jejunum, proximal ileum, and distal ileum, were targeted to examine D-maltose digestion and glucose transport across the intestinal mucosa. In the distal and proximal ileum, glucose concentrations were found to be significantly higher in the serosal compartment of the 1-wk-old chicks upon incubation with D-maltose (25 mM) (P < 0.05), while in the mucosal compartment the levels were significantly higher in the 5-wk-old chickens (P < 0.05). An Ussing chamber setup was employed to measure glucose-induced short-circuit current (ΔIsc) in the mucosal epithelium of the jejunum. In response to the addition of D-maltose (10 mM) into the mucosal compartment, ΔIsc was significantly higher in the 1-wk-old chicks (P = 0.018). Furthermore, no variations in jejunal maltase activity were observed between the 2 age groups. While jejunal glucose absorption was lower in the 5-wk-old chickens, the mRNA expression levels of jejunal SGLT1, GLUT2, and Na+/K+-ATPase did not show any significant differences between the 2 age groups. Our results suggest that the active transport of glucose across the jejunal epithelium decreases upon growth in broiler chickens but is not accompanied by any variations in maltase activity or in the expression of glucose-absorption-related genes.

Newly identified interferon tau-responsive Hes family BHLH transcription factor 4 and cytidine/uridine monophosphate kinase 2 genes in peripheral blood granulocytes during early pregnancy in cows

In cattle, interferon-stimulated genes (ISGs) such as ISG15, MX1, MX2, and OAS1 are known as classic ISGs that are highly involved in the implantation process. Various molecules play a crucial role in the mechanisms underlying ISG effects. Although microarray analyses have highlighted the expression of various molecules during the implantation period, these molecules remain incompletely characterized. In the present study, various specifically expressed genes were selected and their characteristics were examined. The microarray data from peripheral blood leukocytes derived from artificially inseminated cows and granulocytes obtained from embryo-transferred cows, respectively, were used to identify new ISG candidates. Seven common genes, including ISG15 and OAS1, were confirmed, but only 4 of the 5 genes were amplified by reverse transcription quantitative polymerase chain reaction. In addition, 3 expressed sequence tags (ESTs) exhibited significantly greater expression in granulocytes from pregnant cows than that observed in bred nonpregnant cows, and the expression in granulocytes increased after interferon-tau stimulation. Sequence alignment revealed similar sequences within 2 ESTs on the Hairy and enhancer of split (Hes) family basic helix-loop-helix transcription factor 4 (HES4) gene. An additional EST was identified as cytidine/uridine monophosphate kinase 2 (CMPK2). In silico analysis facilitated the identification of transcription factor-binding sequences, including an interferon-stimulated response element and interferon regulatory factor-binding sites, within the promoter region of HES4 and CMPK2. These genes may function as new ISGs in the context of implantation and may participate in the coordination of the feto-maternal interface in cows.

Functional assessment of tandem coronary artery stenosis by intracoronary optical coherence tomography-derived virtual fractional flow reserve: a case series

Background

Optical coherence tomography (OCT)-derived fractional flow reserve (FFR)—which may be calculated using fluid dynamics—demonstrated an excellent correlation with the wire-based FFR. However, the applicability of the OCT-derived FFR in the assessment of tandem lesions is currently unclear.

Case summary

We present two cases of tandem lesions in the mid segment of the left anterior descending (LAD) artery which could have assessed accurately by OCT-derived FFR. The first patient underwent wire-based FFR at the far distal site of LAD, showed a value of 0.66. The OCT-derived FFR was calculated, yielding a value of 0.64. In the absence of stenosis at the proximal lesion, the OCT-derived FFR was calculated as 0.79, which was as same as the wire-based FFR obtained after stenting to the proximal lesion. Thus, additional stenting was performed at the distal lesion. The second patient underwent wire-based FFR at the far distal site of LAD, showed a value of 0.76 which was as same vale as OCT-derived FFR. Considering the absence of stenosis in the proximal lesion, the OCT-derived FFR was estimated as 0.88. After coronary stenting in the proximal lesion, the wire-based FFR yielded a value of 0.90. Therefore, additional intervention to the distal lesion was deferred.

Discussion

The described reports are the first two cases which performed physiological assessment using OCT in tandem lesions. The OCT-derived FFR might be able to estimate the wire-based FFR and the severity of each individual lesion in patients with tandem lesions.

Nosocomial infection by human bocavirus and human rhinovirus among paediatric patients with respiratory risks

BACKGROUND

Nosocomial infections by respiratory viruses undetected by rapid tests are not often diagnosed. For paediatric patients with background diseases, nosocomial infection could be fatal.

AIM

To determine the relationship between developing symptoms by respiratory viruses undetectable by rapid tests and respiratory risks and to improve the management of infection control.

METHODS

Two episodes of nosocomial infection by human bocavirus (HBoV) and human rhinovirus (HRV) were retrospectively investigated in a tertiary hospital paediatric ward in Japan. Viruses were identified by polymerase chain reaction to determine infection control management. When viruses of the same species were detected from different patients, the virus homology was investigated. The relationship between respiratory risks and developing symptoms was statistically investigated.

FINDINGS

Three and four patients with respiratory risks in the HBoV and HRV outbreaks, respectively, developed respiratory symptoms. The nucleotide sequences of two patients in the HBoV outbreak and all four patients in the HRV outbreak were phylogenetically close. In both outbreaks, the patients with respiratory risks developed significantly more symptoms than those without any risk (P = 0.035 and 0.018, respectively). After the patients with respiratory infection were separated from those with respiratory risks, no additional nosocomial infection occurred.

CONCLUSION

Patients with respiratory risks easily develop respiratory symptoms and acquire severe symptoms of nosocomial infection by those viruses. In a paediatric ward, we should adopt not only standard precautions but also isolation management of the patients with respiratory symptoms, even if they have negative results in rapid tests.

Regulatory T cells and M2-polarized tumour-associated macrophages are associated with the oncogenesis and progression of oral squamous cell carcinoma

Regulatory T cells (Tregs) and tumour-associated macrophages (TAMs) contribute to the tumour microenvironment by inhibiting anti-tumour immune responses. This study was performed to investigate the roles of Tregs and TAMs in oral squamous cell carcinoma (OSCC) and oral epithelial precursor lesions (OEPL). The expression of Treg markers CD25 and FoxP3 and TAM markers CD163 and CD204 was investigated in 82 OSCC and 45 OEPL specimens, and their associations with clinicopathological parameters were analyzed. Correlations were found among CD25, FoxP3, CD163, and CD204 levels (P <  0.001), and these targets were up-regulated in OSCC compared to OEPL (P <  0.001). In OSCC, infiltration of Tregs and/or M2 TAMs was associated with sex and clinicopathological features, such as tumour size, nodal metastasis, tissue differentiation, stromal reaction, invasive behaviour, and invasive depth. In OEPL, CD25, FoxP3, CD163, and CD204 immunoreactivities were significantly associated with sex, postoperative recurrence, and cancerization to OSCC. This study is novel in showing that the infiltration of Tregs and M2 TAMs is significantly associated with the progression of premalignant lesions to OSCC. This suggests that these cells represent prognostic biomarkers for premalignant lesion progression and that immunotherapeutic approaches to control Treg/M2 TAM numbers could protect against progression to malignancy.