Bacteriophage-host interactions in Streptococcus thermophilus and their impact on co-evolutionary processes

Bacteriophages (or phages) represent a persistent threat to the success and reliability of food fermentation processes. Recent reports of phages that infect Streptococcus thermophilus have highlighted the diversification of phages of this species. Phages of S. thermophilus typically exhibit a narrow range, a feature that is suggestive of diverse receptor moieties being presented on the cell surface of the host. Cell wall polysaccharides including rhamnose-glucose polysaccharides (RGP) and exopolysaccharides (EPS) have been implicated as being involved in the initial interactions with several phages of this species. Following internalisation of the phage genome, the host presents several defences including CRISPR-Cas and restriction and modification systems to limit phage proliferation. This review provides a current and holistic view of the interactions of phages and their S. thermophilus host cells and how this has influenced the diversity and evolution of both entities.

Predictive value of high-sensitivity troponin for significant coronary artery disease in new-onset atrial fibrillation with rapid ventricular response

BACKGROUND

High-sensitivity troponin-T (HS-cTnT) levels are often measured in patients presenting with atrial fibrillation (AF), with many subjected to unnecessary invasive assessments. The significance of a normal or mildly raised HS-cTnT in this context is poorly understood. This study aimed to determine the predictive value of HS-cTnT for significant coronary artery disease (CAD) in new AF with rapid ventricular response. We also compared the discriminative ability of HS-cTnT to suspected angina for significant CAD.

METHODS

We examined patients presenting with new AF to two tertiary Irish centers in a defined period. Those included had HS-cTnT taken at presentation and subsequent ischemic evaluation.

RESULTS

Of 5350 cases screened for inclusion, 281 were deemed eligible. Of these, 148 and 133 patients had a positive and negative index HS-cTnT, respectively. Of those with negative HS-cTnT, 13 (9.8%) had significant CAD versus 51 (34.5%) with positive HS-cTnT (P < 0.001). Positive Hs-cTnT status remained significant upon multivariate analysis (OR, 2.9; 95% CI, 1.37-6.14; P = 0.005). A similar model where HS-cTnT was replaced with suspected angina produced an OR of 1.64 (95% CI, 0.75-3.59; P = 0.213). A logistic model determined optimal cutoff value for HS-cTnT to be less than 30 ng/l, producing a negative predictive value of 91.8% and area under the receiver operative curve of 83.36.

CONCLUSION

HS-cTnT exhibits potential as an effective screening biomarker to predict nonsignificant CAD in new rapid AF, allowing more targeted and rationalized ischemic testing. HS-cTnT may also be a more accurate predictor of significant CAD than clinically suspected stable angina.Graphical abstract: http://links.lww.com/MCA/A540.

POS0999 HIGHER CARDIOVASCULAR MORBIDITY SEEN IN MEN WITH LONGER DELAY TO THE DIAGNOSIS OF AXIAL SPONDYLOARTHRITIS

Background

Diagnostic delay in axial spondyloarthritis (axSpA) is a well-defined feature of the disease, despite increased awareness. Morbidity and mortality are higher in axSpA than the general population1. Much of this excess burden is due to increased comorbidity. However, the association between delayed diagnosis and increased comorbidity in this population is unknown.

Objectives

(1)Examine the relationship between delayed diagnosis and comorbidity in a large cohort of well characterised individuals with axSpA

(2)Assess the impact of sex on the relationship between diagnostic delay and comorbidity.

Methods

The Ankylosing Spondylitis Registry of Ireland (ASRI), a descriptive epidemiological study of the Irish axSpA population, provided the cohort for this study. A standardised clinical assessment was performed on each patient. Delay to diagnosis was calculated as age at diagnosis minus age at symptom onset. Comorbidities were considered as any condition present in addition to axial SpA, excluding extra-musculoskeletal manifestations (EMM). SPSS was used for statistical analysis, with appropriate tests used for normally and non-normally distributed data.

Results

Of the 913 included patients, 659 (72%) were male and mean age was 46 years (SD 13). Detailed baseline clinical and demographic characteristics are outlined in Table 1. Median delay to diagnosis was 5 (2, 12) years. Comorbidity was present in 37% (n=341) of the cohort, with hypertension the most prevalent (see Figure 1).

Table 1.

Baseline demographic and clinical characteristics

VariableAge, mean (SD)45.8 (12.6)Female, n (%)254 (27.8)Caucasian, n (%)819 (96.5)Ever Smoker, n (%)*527 (57.7)HLA-B27 positive, n (%)631 (89.9)Disease duration, median (25th,75th)17.1 (9.5, 27.8)Delay to diagnosis, median (25th, 75th)5.0 (2.0, 12.0)AAU, n (%)308 (34.4)PsO, n (%)150 (16.7)IBD, n (%)96 (10.7)Biologic use, n (%)628 (68.5)BASMI, mean (SD)3.6 (2.1)BASFI, mean (SD)3.4 (2.9)BASDAI, mean (SD)3.9 (2.4)HAQ, median (25th, 75th)0.38 (0.0, 0.9)

The median delay to diagnosis was significantly longer in those with ≥1 comorbidity compared to those with none (7 v 5 years, p<0.01). Hypertension (6 v 5 years, p=0.1) and cerebrovascular disease (10 v 5 years, p=0.03) were associated with a significantly longer delay to diagnosis, with a similar trend seen in those with hyperlipidaemia (7 v 5 years, p=0.09) and ischaemic heart disease (10 v 5 years, p=0.07). The delay to diagnosis was also longer in those that currently (7 v 5 years, p=0.03) or ever smoked (6 v 5 years, p<0.01). The delay to diagnosis was significantly longer in those with depression (9 v 5, p<0.05). The presence of EMM did not contribute to a delay to diagnosis, and there was no association with any categories of medication.

There was no significant difference in the median delay to diagnosis between females (5 v 6 years) for males. However, there were differences in the relationship between delay to diagnosis and the pattern of comorbidities between sexes. There was a significantly (p<0.05) longer delay to diagnosis in men with cerebrovascular disease (12 v 6 years), ischaemic heart disease (10 v 6 years) and diabetes (10 v 6 years), which wasn’t evident in females. Depression was associated with a longer delay to diagnosis in males (10 v 6 years, p<0.05), but not females (6 v 5 years, p=0.5).

Conclusion

Delay to diagnosis of axSpA was associated with a higher prevalence of comorbidities. This was particularly evident in men, with higher cardiovascular morbidity in those with a longer delay to diagnosis. Further research is needed to determine if shortening the delay to diagnosis would reduce the burden of cardiovascular morbidity.

References

[1]Chaudhary et al. All-Cause and Cause-Specific Mortality in Psoriatic Arthritis and Ankylosing Spondylitis: A Systematic Review and Meta-Analysis. Arthritis Care Res. 2021 Nov 17 (online).

Disclosure of Interests

None declared

POS1001 CURRENT SMOKING IS ASSOCIATED WITH LOWER RISK OF UVEITIS AND PERIPHERAL ARTHRITIS IN MALES WITH AXIAL SPONDYLOARTHRITIS

Background

The associations between smoking and extra-axial manifestations of axial spondyloarthritis (axSpA) are inadequately described. Previous observational studies have demonstrated smoking as protective against some but not other manifestations. However, the impact of sex on these associations is unknown.

Objectives

Using a large descriptive epidemiological dataset, we performed a sex-stratified analysis of the association between smoking status and extra-axial manifestations in axSpA.

Methods

This study was carried out within the framework of ASRI (Ankylosing Spondylitis Registry of Ireland), a descriptive epidemiological study of the axSpA population of Ireland. A standardised clinical assessment was performed on each patient, collecting demographic and clinical data. Smoking status was characterised as current, previous or never. The number of cigarettes per day, plus number of years smoking was also collected. Data on the following extra-axial manifestations was collected: arthritis, enthesitis, dactylitis, acute anterior uveitis (AAU), psoriasis (PsO), inflammatory bowel disease (IBD). Standardised measures of disease severity were also collected. Separate logistic regression models were used to define the association between extra-axial manifestations and smoking, controlling for potential confounders. SPSS was used for statistical analysis.

Results

Smoking data was available for 913 out of the 917 axSpA individuals with data in ASRI (mean age 46 (SD 13) years, disease duration 19 (SD 12) years, 72% male, 97% Caucasian). Twenty eight percent (n=259) were current smokers, 29% (n=268) were past smokers and 42% (n=386) were never smokers. Of the current smokers, the mean number of cigarettes per day was 12 (SD 7) and number of years smoking was 22 (SD 12). Thirty one percent had peripheral arthritis, 7% had dactylitis, 18% had enthesitis, 34% had AAU, 17% had psoriasis and 11% had IBD.

Current smokers had a significantly lower prevalence of arthritis and uveitis than past or non-smokers (see Table 1). A sex-stratified analysis was performed. There was no association between smoking status and any extra-axial manifestation in females. However, current smoking was associated with lower prevalence of arthritis in males compared to past or non-smokers (22% v 36% v 42%, p=0.002). A similar pattern was seen for uveitis, where male current smokers had a lower prevalence than non-smokers (24% v 38%, p=0.01). In contrast, psoriasis was more prevalent in men who were current smokers compared to non-smokers (18% v 12%, p=0.01), with no difference seen in females. There was no association with number of cigarettes smoked or number of years smoking.

Table 1.

Association between smoking status and extra-axial manifestations in axSpA.

AxSpA cohortCurrent smokerPast smokerNon-smokerArthritis30.9%22.4%a35.5%b33.3%bDactylitis6.7%5.5%a6.7% a7.4% aEnthesitis18.1%17.4% a16.2% a19.9% aUveitis34.3%27.4%a35.0%b38.6%bPsoriasis16.7%18.5% a19.3% a13.8% aInflammatory bowel disease10.7%9.9% a13.2% a9.5% a

Different subscript letters denote significant (p<0.05) differences between groups. Significant values highlighted in bold.

There was no association between smoking status and disease severity by subjective or objective measures, either for the cohort as a whole or by sex.

When compared to non- or ex-smokers and controlled for potential confounders including sex, age, biologic use, the association remained only between current smokers and lower risk of uveitis (OR 0.68, 95% CI 0.49 to 0.96) and arthritis (OR 0.62, 95% CI 0.43 to 0.88), in separate logistic regression models. The association between current smoking and increased prevalence of psoriasis in males did not remain significant once controlled for confounders (OR 1.10, 96% CI 0.73 to 1.65).

Conclusion

We demonstrated that current smoking is independently associated with a lower risk of uveitis and arthritis in males with axSpA, but not females. More research is needed to further investigate this paradoxical finding.

Disclosure of Interests

None declared

POS0995 EFFECT OF SEX IN CO-EXISTENT FIBROMYALGIA AND ENTHESITIS IN SPONDYLOARTHRITIS: ANCILLARY ANALYSIS OF THE ASAS-PerSpA STUDY

Background:

Enthesitis is a common feature of axial spondyloarthropathy (axSpA) and psoriatic arthritis (PsA). Up to 25% of individuals with axSpA and PsA have a co-existing diagnosis of fibromyalgia syndrome (FMS). The anatomic overlap between tender points in FMS and sites of entheses is a challenge when differentiating between active SpA and FMS. Literature investigating the co-existence of enthesitis and FMS in individuals with SpA is sparse, in particular the effect of sex. The ASAS Peripheral involvement in Spondyloarthritis (PerSpA) study aims to characterize peripheral musculoskeletal in individuals with SpA across the world.

Objectives:

(1)To characterise the co-existence of enthesitis and FMS in individuals with SpA.

(2)To explore the effect of sex on the presence of FMS and enthesitis.

Methods:

All individuals from the cross-sectional multinational ASAS-PerSpA study with a diagnosis of axSpA, peripheral SpA (pSpA) or PsA according to their rheumatologist were included. The Fibromyalgia Rapid Screening Tool (FiRST) was used to make the diagnosis of FMS. The baseline descriptive and clinical differences between sexes were performed using T-tests and crosstabs. Sex-stratified comparisons within the following categories were conducted using chi-square analysis and ANOVA as appropriate: (1) enthesitis & fibromyalgia; (2) enthesitis only; (3) fibromyalgia only; (4) neither.

Results:

Baseline characteristics of the 4465 included patients are outlined in Table 1, stratified by sex. Enthesitis occurred in 44% (n=1984) of the population and was more common in females than males (48% vs 42%, p<0.01). The majority affected had intermittent episodes of enthesitis (55%, n=1088), with the Achilles tendon and plantar fascia the two most common sites in both sexes. Enthesitis was more often confirmed on imaging in females than males (44% v 35%, p<0.01). The most common treatment for enthesitis was non-steroidal anti-inflammatories (97%, n=1318), with no difference when stratified by sex. FMS occurred in 19% (n=775) of patients and was more common in females than males (28% vs 13%, p<0.01).

Table 1.

Participant characteristics, stratified by sex. Values are mean (SD), median (25th, 75th) or n (%). P-values are independent T-tests or Mann-Whitney as appropriate.

VariableTotalMaleFemaleP valueN446527241741Age, years45 (14)43 (14)46 (13)<0.01Disease duration, years11 (6, 20)12 (6, 21)11 (5, 19)0.01Delay to diagnosis, years3 (1, 9)3 (1, 9)3 (1, 10)0.11HLA-B27 positive2066 (66)1457 (73)609 (54)<0.01Radiographic sacroiliitis2517 (61)1788 (70)729 (46)<0.01Sacroiliitis on MRI1817 (65)1128 (68)689 (60)<0.01axSpA ASAS criteria2910 (65)1953 (72)957 (55)<0.01pSpA ASAS criteria555 (12)250 (9)305 (18)<0.01CASPAR criteria1043 (23)508 (19)535 (31)<0.01BMI, kg/m226 (23, 29)26 (23, 29)26 (23, 30)0.24Axial involvement3428 (76.8)2243 (82.3)1185 (68.1)<0.01Peripheral involvement2541 (56.9)1404 (51.5)1137 (65.3)<0.01Enthesitis1984 (44.4)1149 (42.2)835 (48.0)<0.01Uveitis738 (17)482 (18)256 (15)0.01Psoriasis1212 (27)615 (23)597 (34)<0.01Inflammatory bowel disease275 (6)150 (6)125 (7)0.02

Enthesitis and FMS occurred together in 10% of the cohort, was more common in women than men (see Figure 1) and was associated with a significantly (p<0.01) longer delay to diagnosis of 1.8 years and a higher BMI of 2.1 kg/m2 than people with enthesitis only. Objective confirmation of enthesitis was similar in those with and without FMS (38% vs 38%, p=0.92).

The presence of FMS added to the burden of disease in those with enthesitis as assessed by BASDAI (6.4 vs 3.6, p<0.01) and ASDAS-CRP (3.5 vs 2.5, p<0.01), with no difference between sexes (p>0.05).

Conclusion:

In this large cross-sectional multinational analysis, FMS affected 19% of individuals with SpA. The co-existence of enthesitis and FMS occurred in 16% of females compared to 6% of males. The presence of FMS increased the burden of disease in those with enthesitis, as assessed by BASDAI and ASDAS-CRP, with no difference between men and women.

Disclosure of Interests:

Gillian Fitzgerald: None declared, Sinead Maguire Grant/research support from: Recipient of Gilead Inflammation Fellowship, Finbar Barry O’Shea: None declared, Clementina López-Medina: None declared, Maxime Dougados: None declared, Nigil Haroon Speakers bureau: Received honorarium from AbbVie, Eli Lilly, Jannsen, Novartis, UCB, Consultant of: AbbVie, Eli Lilly, Jannsen, Novartis, UCB, Grant/research support from: AbbVie, Eli Lilly, Jannsen, Novartis, UCB.

High-sensitivity troponin assays: development and utility in a modern health-care system

Introduction: The introduction of cardiac troponin (cTn) assays have revolutionized the diagnosis and management of acute myocardial infarction in Emergency Departments worldwide. Its success has led to significant research and development investment in this area culminating in the development of newer high-sensitivity cardiac troponin assays (hs-cTn). While these newer assays allow for more rapid diagnosis by decreasing the time interval between serial data points, there is an inevitable trade off between increasing sensitivity and specificity. This review examines in detail the introduction and implementation of hs-cTN and its implications for clinical practice.Areas covered: This article reviews the history and development of high-sensitivity troponin assays and their application to clinical practice and current evidence base. It also discusses both the positive and negative aspects of the continuing increasing sensitivity of biochemical assays and the translation of this into clinical practice. Potential future developments are also discussed.Expert commentary: It is clear that there are many benefits to detecting extremely low concentration of cardiac troponin including the development of rapid rule out algorithms and the cost and time-saving advantages associated with the quicker movement of patients through the health-care system. It is important to note however that detecting troponin at very low concentrations also dramatically increases the false-positive rates and leads to a potentially large increase in invasive testing and diagnosis of myocardial infarction.

Metabolic syndrome in polycystic ovary syndrome: a systematic review, meta-analysis and meta-regression

Women with polycystic ovary syndrome (PCOS) have increased risk of metabolic syndrome. The relative contribution of clinical, demographic or biochemical factors to metabolic syndrome in PCOS is not known. A literature search was conducted in MEDLINE, CINAHL, EMBASE and clinical trial registries. Of 4530 studies reviewed, 59 were included in the systematic review and 27 in the meta-analysis and meta-regression. In good and fair quality studies, women with PCOS had an overall increased prevalence of metabolic syndrome (odds ratio, OR 3.35, 95% confidence interval, CI 2.44, 4.59). Increased prevalence of metabolic syndrome occurred in overweight or obese women with PCOS (OR 1.88, 95% 1.16, 3.04) but not in lean women (OR 1.45, 95% CI 0.35, 6.12). In meta-regression analyses, the markers of metabolic syndrome diagnostic criteria (waist circumference, high-density lipoprotein cholesterol, triglyceride, blood pressure), BMI, glucose tolerance (2-hr oral glucose tolerance test) and surrogate markers of insulin resistance (HOMA-IR) but not markers of reproductive dysfunction (sex hormone binding globulin, testosterone, PCOS phenotypes) contributed significantly to the heterogeneity in the prevalence of metabolic syndrome. Women with PCOS have increased risk of metabolic syndrome which was associated with obesity and metabolic features but not with indices of hyperandrogenism.

Giant Cell Arteritis Presenting as an Ischaemic Upper Limb

Aim To present an interesting case of giant cell arteritis presenting as ischaemic upper limb. Methods Data was collected from the patient’s chart and from radiology and laboratory systems in our institution. Results The patient had a temporal artery biopsy confirming the diagnosis of temporal arteritis. This was successfully treated with high dose steroids leading to resolution of symptoms in the arm. Conclusion Arteritis is an important consideration to consider in patients who present with limb ischaemia as it is a reversible cause which can be treated effectively.

Vestibular Reactivity to Caloric Stimulation in Schizophrenics

Abnormalities in the vestibular reactions in schizophrenics have been reported in the literature. Pekelsky (1921) observed transitory lack of caloric response in two cases of catatonic stupor. Rosenfeld (1926) described four cases of acute catatonia in which on calorization a slow deviation appeared instead of the physiological response. Claude, Baruk and Aubry (1927) examined four cases of catatonia, eight of hebephrenia and one of dementia paranoides. In one of the catatonic cases no caloric or galvanic response could be elicited, and in the three others the reactions were diminished. The other cases showed normal reactions. The authors stated that a diminution of the responses could sometimes be observed in hysteria. Claude, Bourguignon and Baruk (1932) found the Chronaxie of the vestibular nerves greatly increased in patients with catalepsy, but normal after the disappearance of that symptom. Joo and Meduna (1935) stated that in old-standing cases of schizophrenia a lack or a considerable diminution of the vestibular responses could nearly always be found. Sercl and Vinar (1937) examined the vestibular reactivity in twelve cases of hebephrenia and thirteen cases of paranoid schizophrenia. The responses to rotation were normal in all cases. The caloric responses were found to be diminished or lacking. Lack of caloric response was more frequent in the hebephrenic than in the paranoid cases. Löwenbach (1936), working on Gjessing's cases of periodic catatonia, carried out quantitative investigations taking into account the latency period of nystagmus, its duration and the number of oscillations. He examined thirty cases, each of them repeatedly, and attempted to correlate the results of the tests with the periodical changes in the clinical picture. He found that shortly before and during periods of stupor the vestibular reactivity dropped, and that sometimes only a slow deviation could be elicited. The lowering of the frequency was due to the prolongation of the slow phase. The abnormalities were independent of the duration of the illness, and in some old-standing cases the response was normal. Sometimes a temporarily diminished reactivity was noticed which did not coincide with a change in the clinical picture. Löwenbach noted frequent and often abrupt changes in individual cases, and in some he observed transitory complete loss of reaction. Angyal and Blackman (1940) studied vestibular reactivity to caloric and rotatory stimulation in 58 unselected male schizophrenics and in 20 normal controls. The response to caloric stimulation was found to be considerably lowered, the rotatory response only slightly reduced. There was no correlation to the duration of hospitalization or to the conventional subtypes of schizophrenia. However, in a group of five patients with extreme apathy, indifference and poverty of mental contents the reactivity was particularly low. In cases with a periodical course the vestibular reactivity was distinctly lower during the catatonic periods than during the intervals. The same authors (1941) investigated the nystagmic reactions to caloric stimulation under the influence of alcohol, hyperpnoea and CO-inhalation in schizophrenics and normal persons. While in normals alcohol intake results in an increase in the frequency of the nystagmus, in schizophrenics a decrease was observed. CO, which normally has a depressing effect on the nystagmic reaction, produced an increase in schizophrenics. Hyperpnoea, while causing an increase in normals, had the opposite effect in schizophrenics. Freeman and Rodnick (1942) studied the amount of sway induced by rotation in thirty schizophrenics and in an equal number of normal controls. The patients were found to be significantly less reactive than the normal subjects.

Multiplex PCR to detect bacteriophages from natural whey cultures of buffalo milk and characterisation of two phages active against Lactococcus lactis, ΦApr-1 and ΦApr-2

This work investigated bacteriophage induced starter failures in artisanal buffalo Mozzarella production plants in Southern Italy. Two hundred and ten samples of whey starter cultures were screened for bacteriophage infection. Multiplex polymerase chain reaction (PCR) revealed phage infection in 28.56% of samples, all showing acidification problems during cheese making. Based on DNA sequences, bacteriophages for Lactococcus lactis (L. lactis), Lactobacillus delbruekii (L. delbruekii) and Streptococcus thermophilus (S. thermophilus) were detected. Two phages active against L. lactis, ΦApr-1 and ΦApr-2, were isolated and characterised. The genomes, approximately 31.4 kb and 31 kb for ΦApr-1 and ΦApr-2 respectively, consisted of double-stranded linear DNA with pac-type system. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‑PAGE) showed one major structural protein of approximately 32.5 kDa and several minor proteins. This is the first report of phage isolation in buffalo milk and of the use of multiplex PCR to screen and study the diversity of phages against Lactic Acid Bacteria (LAB) strains in artisanal Water Buffalo Mozzarella starters.

Engaging the public in healthcare decision-making: results from a Citizens' Jury on emergency care services

BACKGROUND

Policies addressing ED crowding have failed to incorporate the public's perspectives; engaging the public in such policies is needed.

OBJECTIVE

This study aimed at determining the public's recommendations related to alternative models of care intended to reduce crowding, optimising access to and provision of emergency care.

METHODS

A Citizens' Jury was convened in Queensland, Australia, to consider priority setting and resource allocation to address ED crowding. Twenty-two jurors were recruited from the electoral roll, who were interested and available to attend the jury from 15 to 17 June 2012. Juror feedback was collected via a survey immediately following the end of the jury.

RESULTS

The jury considered that all patients attending the ED should be assessed with a minority of cases diverted for assistance elsewhere. Jurors strongly supported enabling ambulance staff to treat patients in their homes without transporting them to the ED, and allowing non-medical staff to treat some patients without seeing a doctor. Jurors supported (in principle) patient choice over aspects of their treatment (when, where and type of health professional) with some support for patients paying towards treatment but unanimous opposition for patients paying to be prioritised. Most of the jurors were satisfied with their experience of the Citizens' Jury process, but some jurors perceived the time allocated for deliberations as insufficient.

CONCLUSIONS

These findings suggest that the general public may be open to flexible models of emergency care. The jury provided clear recommendations for direct public input to guide health policy to tackle ED crowding.

Protein quality and the protein to carbohydrate ratio within a high fat diet influences energy balance and the gut microbiota in C57BL/6J mice

Macronutrient quality and composition are important determinants of energy balance and the gut microbiota. Here, we investigated how changes to protein quality (casein versus whey protein isolate; WPI) and the protein to carbohydrate (P/C) ratio within a high fat diet (HFD) impacts on these parameters. Mice were fed a low fat diet (10% kJ) or a high fat diet (HFD; 45% kJ) for 21 weeks with either casein (20% kJ, HFD) or WPI at 20%, 30% or 40% kJ. In comparison to casein, WPI at a similar energy content normalised energy intake, increased lean mass and caused a trend towards a reduction in fat mass (P = 0.08), but the protein challenge did not alter oxygen consumption or locomotor activity. WPI reduced HFD-induced plasma leptin and liver triacylglycerol, and partially attenuated the reduction in adipose FASN mRNA in HFD-fed mice. High throughput sequence-based analysis of faecal microbial populations revealed microbiota in the HFD-20% WPI group clustering closely with HFD controls, although WPI specifically increased Lactobacillaceae/Lactobacillus and decreased Clostridiaceae/Clostridium in HFD-fed mice. There was no effect of increasing the P/C ratio on energy intake, but the highest ratio reduced HFD-induced weight gain, fat mass and plasma triacylglycerol, non-esterified fatty acids, glucose and leptin levels, while it increased lean mass and oxygen consumption. Similar effects were observed on adipose mRNA expression, where the highest ratio reduced HFD-associated expression of UCP-2, TNFα and CD68 and increased the diet-associated expression of β3-AR, LPL, IR, IRS-1 and GLUT4. The P/C ratio also impacted on gut microbiota, with populations in the 30/40% WPI groups clustering together and away from the 20% WPI group. Taken together, our data show that increasing the P/C ratio has a dramatic effect on energy balance and the composition of gut microbiota, which is distinct from that caused by changes to protein quality.

"In somno securitas" anaesthetists' noise exposure in Orthopaedic operating theatres

Excessive noise exposure can have adverse effects on the health and performance of healthcare providers. Irish statutory regulations limit daily workplace noise exposure to 87 A-weighted decibels [dB(A)]. The World Health Organisation recommends noise levels remain under 35 dB(A) in patient treatment rooms. We measured anaesthetists' noise exposure during elective orthopaedic surgery. The mean and maximum sound levels were 63.0 (SD 4.26) and 92.8 dB(A) respectively. Noise was louder than 65 dB(A) 22.2% of the time and louder than 80 dB(A) less than 1% of the time. Staff conversation and metal instruments were responsible for 29.5% and 19.9% of peaks louder than 65 dB(A) respectively. Sound levels recorded were lower than recognised levels associated with hearing loss. Sound regularly exceeded World Health Organisation (WHO) recommended levels for patient comfort and safety. Anaesthetists need to be aware of the influence of environmental noise on clinical practice.

Health care system in Saudi Arabia: an overview

The government of Saudi Arabia has given high priority to the development of health care services at all levels: primary, secondary and tertiary. As a consequence, the health of the Saudi population has greatly improved in recent decades. However, a number of issues pose challenges to the health care system, such a shortage of Saudi health professionals, the health ministry's multiple roles, limited financial resources, changing patterns of disease, high demand resulting from free services, an absence of a national crisis management policy, poor accessibility to some health care facilities, lack of a national health information system, and the underutilization of the potential of electronic health strategies. This paper reviews the historical development and current structure of the health care system in Saudi Arabia with particular emphasis on the public health sector and the opportunities and challenges confronting the Saudi health care system.

Diet–tissue discrimination factors of carbon and nitrogen stable isotopes in blood of Snowy Owl (Bubo scandiacus)

Analysis of carbon (13C/12C) and nitrogen (15N/14N) stable isotope ratios (hereafter δ13C and δ15N, respectively) in animal tissues is a powerful tool in food-web studies. However, isotopic ratios of prey are not transmitted directly to a consumer, as a diet–tissue discrimination factor (denoted Δ) occurs between sources and consumer’s tissues. An accurate assessment of the diet of a consumer with stable isotopes thus requires that the Δ13C and Δ15N of the studied species are known. Our aim was to establish Δ13C and Δ15N values in the Snowy Owl ( Bubo scandiacus (L., 1758)). Moreover, we assessed the potential effect of ethanol preservation of blood samples on δ13C and δ15N values. We kept four captive adult Snowy Owls on a pure diet of mice for ≥6 weeks. We then collected mouse muscle and blood samples from the owls and analyzed their δ13C and δ15N values. Δ13C and Δ15N values (mean ± SE) for owl blood were +0.3‰ ± 0.2‰ and +1.9‰ ± 0.1‰, respectively. These values are the first discrimination factors ever reported in Strigiformes and are lower, for Δ15N, than those obtained in terrestrial carnivores and other bird species, including falcons. Preservation in ethanol did not significantly affect δ13C and δ15N values.

Composition, variability, and temporal stability of the intestinal microbiota of the elderly

Alterations in the human intestinal microbiota are linked to conditions including inflammatory bowel disease, irritable bowel syndrome, and obesity. The microbiota also undergoes substantial changes at the extremes of life, in infants and older people, the ramifications of which are still being explored. We applied pyrosequencing of over 40,000 16S rRNA gene V4 region amplicons per subject to characterize the fecal microbiota in 161 subjects aged 65 y and older and 9 younger control subjects. The microbiota of each individual subject constituted a unique profile that was separable from all others. In 68% of the individuals, the microbiota was dominated by phylum Bacteroides, with an average proportion of 57% across all 161 baseline samples. Phylum Firmicutes had an average proportion of 40%. The proportions of some phyla and genera associated with disease or health also varied dramatically, including Proteobacteria, Actinobacteria, and Faecalibacteria. The core microbiota of elderly subjects was distinct from that previously established for younger adults, with a greater proportion of Bacteroides spp. and distinct abundance patterns of Clostridium groups. Analyses of 26 fecal microbiota datasets from 3-month follow-up samples indicated that in 85% of the subjects, the microbiota composition was more like the corresponding time-0 sample than any other dataset. We conclude that the fecal microbiota of the elderly shows temporal stability over limited time in the majority of subjects but is characterized by unusual phylum proportions and extreme variability.

Impact of administered bifidobacterium on murine host fatty acid composition

Recently, we reported that administration of Bifidobacteria resulted in increased concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in murine adipose tissue [1]. The objective of this study was to assess the impact of co-administration of Bifidobacterium breve NCIMB 702258 and the substrate for EPA, alpha-linolenic acid, on host fatty acid composition. alpha-Linolenic acid-supplemented diets (1%, wt/wt) were fed to mice (n = 8), with or without B. breve NCIMB 702258 (daily dose of 10(9) microorganisms) for 8 weeks. Two further groups received either supplement of B. breve alone or unsupplemented diet. Tissue fatty acid composition was assessed by gas liquid chromatography. Dietary supplementation of alpha-linolenic acid resulted in higher (P < 0.05) alpha-linolenic acid and EPA concentrations in liver and adipose tissue and lower (P < 0.05) arachidonic acid in liver, adipose tissue and brain compared with mice that did not receive alpha-linolenic acid. Supplementation with B. breve NCIMB 702258 in combination with alpha-linolenic acid resulted in elevated (P < 0.05) liver EPA concentrations compared with alpha-linolenic acid supplementation alone. Furthermore, the former group had higher (P < 0.05) DHA in brain compared with the latter group. These results suggest a role for interactions between fatty acids and commensals in the gastrointestinal tract. This interaction between administered microbes and fatty acids could result in a highly effective nutritional approach to the therapy of a variety of inflammatory and neurodegenerative conditions.

Predicting freedom from clinical events in non-ST-elevation acute coronary syndromes: the Global Registry of Acute Coronary Events

OBJECTIVE

To identify patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) with a low likelihood of any adverse in-hospital event.

DESIGN, SETTING AND PATIENTS

Data were analysed from 24 097 patients with NSTEMI or unstable angina included in the Global Registry of Acute Coronary Events (January 2001 to September 2007).

MAIN OUTCOME MEASURES

In-hospital events were myocardial infarction, arrhythmia, congestive heart failure or shock, major bleeding, stroke or death. Two-thirds of the patients were randomly chosen for model development and the remainder for model validation. Multiple logistic regression identified predictors of freedom from an in-hospital event, and a Freedom-from-Event score was developed.

RESULTS

Of the 16 127 patients in the model development group, 19.1% experienced an in-hospital adverse event. Fifteen factors independently predicted freedom from an adverse event: younger age; lower Killip class; unstable angina presentation; no hypotension; no ST deviation; no cardiac arrest at presentation; normal creatinine; decreased pulse rate; no hospital transfer; no history of diabetes, heart failure, peripheral arterial disease, or atrial fibrillation; prehospital use of statins, and no chronic warfarin. In the validation group, 18.6% experienced an adverse event. The model discriminated well between patients experiencing an in-hospital event and those who did not in both derivation and validation groups (c-statistic = 0.77 in both). Patients in the three lowest risk deciles had a very low in-hospital mortality (<0.5%) and an uncomplicated clinical course (>93% event-free in hospital). The model also predicted freedom from postdischarge events (death, myocardial infarction, stroke; c-statistic = 0.77).

CONCLUSIONS

The GRACE Freedom-from-Event score can predict the in-hospital course of NSTE-ACS, and identifies up to 30% of the admitted population at low risk of death or any adverse in-hospital event.

Inhibitory effect of conjugated alpha-linolenic acid from bifidobacteria of intestinal origin on SW480 cancer cells

In this study, we assessed the ability of six strains of bifidobacteria (previously shown by us to possess the ability to convert linoleic acid to c9, t11-conjugated linoleic acid (CLA) to grow in the presence of alpha-linolenic acid and to generate conjugated isomers of the fatty acid substrate during fermentation for 42 h. The six strains of bifidobacteria were grown in modified MRS (mMRS) containing alpha-linolenic acid for 42 h at 37 degrees C, after which the fatty acid composition of the growth medium was assessed by gas liquid chromatography (GLC). Indeed, following fermentation of one of the strains, namely Bifidobacterium breve NCIMB 702258, in the presence of 0.41 mg/ml alpha-linolenic acid, 79.1% was converted to the conjugated isomer, C18:3 c9, t11, c15 conjugated alpha-linolenic acid (CALA). To examine the inhibitory effect of the fermented oils produced, SW480 colon cancer cells were cultured in the presence of the extracted fermented oil (10-50 microg/ml) for 5 days. The data indicate an inhibitory effect on cell growth (p <or= 0.001) of CALA, with cell numbers reduced by 85% at a concentration of 180 microM, compared with a reduction of only 50% with alpha-linolenic acid (p <or= 0.01).

Using dried blood spots stored on filter paper to measure cholinesterase activity in wild avian species

Birds of prey that are poisoned by cholinesterase inhibitors (e.g. organophosphate and carbamate insecticides) are often cared for at animal shelters, rehabilitation centres and wildlife diagnostic facilities. Plasma cholinesterase (ChE) activity is a recognized method of assessing exposure to these insecticides, but standard blood-handling protocols are difficult to follow in non-laboratory settings. The primary objective of this study was to expand upon a method for storing human blood on filter paper without the need for complicated equipment or refrigeration, and to test its utility for measurement of ChE activity in avian blood. ChE activity from whole blood, plasma, and dried blood spots was analysed from 169 wild birds and comparisons made among sample types. ChE activity measured in whole blood haemolysates and dried blood spots were significantly correlated (r = 0.74, p < 0.001), as was ChE activity measured in plasma and dried blood spots (r = 0.68, p < 0.001). This study demonstrated that monitoring pesticide exposure in birds could be conducted using elementary blood sampling, preserving and shipping techniques.

Life under stress: the probiotic stress response and how it may be manipulated

The continuing expansion of interest in probiotic bacteria has led to an increase in manufactured Functional Foods and medicines containing these bacteria. Given the intestinal origin of these microorganisms, the challenges these sensitive bacteria face in order to be in a highly viable state throughout processing, storage and gastrointestinal transit to the site of action in the human gut are enormous. These bacteria encounter stresses including temperature, acid, bile, exposure and osmotic and oxidative stress in both product matrices and during gastrointestinal transit. However, like all bacteria, probiotic bacteria retain a broad arsenal of molecular mechanisms to combat the often lethal environmental stresses encountered during processing and following ingestion. A comprehensive appreciation of these mechanisms should inevitably lead to the design and manufacture of probiotic cultures, which retain greater viability through to the target site in the intestine. This review attempts to catalogue the cellular processes available to probiotic bacteria to facilitate survival in stressful conditions, and to speculate on how manipulation of these cellular systems can lead to production of designer strains with enhanced viability in food systems and efficacy following ingestion.

Sex-related differences in the presentation, treatment and outcomes among patients with acute coronary syndromes: the Global Registry of Acute Coronary Events

OBJECTIVE

To assess whether sex differences exist in the angiographic severity, management and outcomes of acute coronary syndromes (ACS).

METHODS

The study comprised 7638 women and 19 117 men with ACS who underwent coronary angiography and were included in GRACE (Global Registry of Acute Coronary Events) from 1999-2006. Normal vessels/mild disease was defined as <50% stenosis in all epicardial vessels; advanced disease was defined as >or=one vessel with >or=50% stenosis.

RESULTS

Women were older than men and had higher rates of cardiovascular risk factors. Men and women presented equally with chest pain; however, jaw pain and nausea were more frequent among women. Women were more likely to have normal/mild disease (12% vs 6%, p<0.001) and less likely to have left-main and three-vessel disease (27% vs 32%, p<0.001) or undergo percutaneous coronary intervention (65% vs 68%, p<0.001). Women and men with normal and mild disease were treated less aggressively than those with advanced disease. Women with advanced disease had a higher risk of death (4% vs 3%, p<0.01). After adjustment for age and extent of disease, women were more likely to have adverse outcomes (death, myocardial infarction, stroke and rehospitalisation) at six months compared to men (odds ratio 1.24, 95% confidence interval 1.14 to 1.34); however, sex differences in mortality were no longer statistically significant.

CONCLUSIONS

Women with ACS were more likely to have cardiovascular disease risk factors and atypical symptoms such as nausea compared with men, but were more likely to have normal/mild angiographic coronary artery disease. Further study regarding sex differences related to disease severity is warranted.

Subtractive screening for probiotic properties of lactobacillus species from the human gastrointestinal tract in the search for new probiotics

In the search for new probiotics, 61 Lactobacillus spp. isolates, belonging to 12 species and isolated as dominant lactic acid bacteria from the feces of healthy humans, were subjected to a subtractive system of in vitro analyses, which included desirable and undesirable traits. Twenty-four isolates were able to grow in 2% bovine bile, of which 13 grew in acidified broth at pH 3.5 in acidified cysteine-containing MRS broth. Intrinsic resistance to certain antimicrobial agents (cefoxitin, metronidazole, vancomycin) was observed in most isolates, but atypical resistances to erythromycin, clindamycin, or tetracycline were also found in 5 strains. Undesirable traits such as alpha-chymotrypsin or N-acetyl-beta-glucosaminidase activities were not detected, but low beta-glucuronidase and moderate beta-glucosidase activities were recorded in 2 strains. Two Lactobacillus gasseri and 2 Lactobacillus paracasei selected strains inhibited several intestinal pathogens in an agar spot test, including strains of Escherichia coli, Listeria monocytogenes, Salmonella typhimurium, and Staphylococcus aureus. They also adhered to human Caco-2 and HT-29 epithelial cells in a manner comparable to Lactobacillus rhamnosus strain GG, and were unable to degrade pig gastric mucin in a plate assay. Together, these results suggest these 4 strains to be good probiotic candidates, concluding that the subtractive screening devised in this work could be a valuable tool in large-scale surveys for probiotics.

Salmonella enterica phage-resistant mutant colonies display an unusual phenotype in the presence of phage Felix 01

AIMS

To investigate irregular colony morphology formation in Salmonella enterica serovar Typhimurium DPC6046 in the presence of a lytic phage, Felix 01.

METHODS AND RESULTS

Phage-resistant derivatives of the parent strain DPC6046 were isolated which exhibited an irregular colony morphology. These were subjected to viability studies by using confocal scanning laser microscopy and live/dead BacLight stain to evaluate the cell viability within the colony. The phenomenon was also observed with other S. enterica serotypes tested which were normally sensitive to phage Felix. In the case of strain DPC6046, dead cells were clearly evident at the irregular edges of the phage-resistant colonies in locations where the cell density was lower. This colony morphology was not apparent with two other Salmonella phages tested.

CONCLUSIONS

These findings support the hypothesis that the unusual morphology is due to reversion to phage sensitivity and consequent cell death within the colony as it forms.

SIGNIFICANCE AND IMPACT OF THE STUDY

The irregular colony morphology observed is peculiar to phage Felix. The confocal scanning laser microscopy methodology allowed the basis for the irregular morphology to be elucidated.

Genomic diversity of cultivable Lactobacillus populations residing in the neonatal and adult gastrointestinal tract

The objective of this study was to investigate the cultivable Lactobacillus population in adult and infant faecal material to identify strains shared across a number of individuals. A range of lactobacilli isolated on Lactobacillus-selective agar from faeces of 16 infants and 11 adults were genetically fingerprinted and further characterized by 16S rRNA gene sequencing. The relatedness of all the Lactobacillus strains isolated to known species was also determined both genetically and phenotypically. This study revealed that the human intestine is initially colonized by only a few (1-2) different cultivable strains whereas in adults the pattern becomes more complex with a higher diversity of strains. The adult samples contained three genetically distinct Lactobacillus strains in some cases, while infant samples generally harboured only one dominant Lactobacillus strain. Moreover, the species in general appeared to differ with Lactobacillus rhamnosus and Lactobacillus casei/paracasei found mainly in adults, whereas Lactobacillus gasseri and Lactobacillus salivarius were more commonly isolated in infant samples. The data reaffirm the differences in Lactobacillus populations both between individual subjects and between the infant and adult, with an overall change in the diversity and complexity from early stages of life to adulthood.

Bifidobacterium lactis Bb-12 and Lactobacillus salivarius UCC500 modify carboxylic acid formation in the hindgut of rats given pectin, inulin, and lactitol

The effect of Bifidobacterium lactis (Bb-12) and Lactobacillus salivarius (UCC500) on the formation of carboxylic acids (CAs) was studied in the hindgut of rats fed pectin, inulin of low solubility, and lactitol. When the pectin diet was supplemented with Bb-12, the formation of CAs was larger throughout the colon of rats, due to increased formation of acetic acid (P < 0.01) and, in the distal part of the colon, also because of propionic and butyric acids (P < 0.01). In rats fed pectin and UCC500, there was a shift in the formation of CAs from the cecum to the distal colon. Thus, the cecal pool of CAs in the rats was lower (P < 0.05), whereas the concentration of CAs in the distal part of colon was larger (P < 0.01) than without this strain. Concerning the slowly fermentable inulin, there was a greater formation of CAs in the cecum (P < 0.05) of rats, especially propionic acid, and a lower formation in the distal part of the colon (P < 0.01) when the diets were supplemented with Bb-12, whereas UCC500 had no effect except for a lower proportion of acetic acid in the distal part of the colon (P < 0.001). In rats fed lactitol and Bb-12, the concentration of CAs was lower in the distal part of colon (P < 0.001) than without this strain, whereas the cecal pool of CAs was greater in rats supplemented with UCC500 (P < 0.001). We conclude that the probiotic bacteria affect the amount, the pattern, and the site of release of CAs in the hindgut of rats, but the combination of pre- and probiotics is of great importance for the outcome.

Sequence analysis of the plasmid genome of the probiotic strain Lactobacillus paracasei NFBC338 which includes the plasmids pCD01 and pCD02

Lactobacillus paracasei NFBC338 is a probiotic strain that was isolated from the human gastrointestinal tract (GIT) and contains a plasmid genome of 80kb. Using a shotgun sequencing approach, two of the plasmids, pCD01 (19,882bp) and pCD02 (8554bp) have been completely sequenced, and four contiguous sequences (Contigs) have been assembled. Bioinformatic analysis of pCD01 revealed that it contains 23 putative open reading frames (ORFs) and that it contains regions characterised by potential replication functions and multidrug resistance (MDR). In contrast, the content of pCD02 is mainly cryptic, although, it does contain two insertion sequence (IS) elements. Indeed, up to 17% of the entire plasmid genome encodes putative transposable elements. In addition, there are a number of interesting ORFs distributed over the four Contigs that show significant homology to genes such as those involved in adherence and biotin metabolism, which may prove beneficial to Lb. paracasei NFBC338 under certain environmental conditions. This study provides a novel insight into the rich plasmid complement of this probiotic Lactobacillus strain, which may potentially be exploited as the basis for development of improved genetic tools for probiotic lactobacilli.

Microbial contamination of dental unit water systems

INTRODUCTION

Dental unit water systems (DUWS) may serve as a reservoir for biofilms that contribute to high numbers of bacteria in the water used during dental treatment. These microbes are predominantly harmless but potentially pathogenic organisms can also be present in the biofilm. This may pose a potential health risk for patients and dental personnel.

AIM

to determine the microbial levels of DUWS in dental practices.

MATERIALS AND METHOD

A cross-sectional study of water and tubing samples from 30 general dental practices (15 health board and 15 private surgeries) was undertaken as part of a pan-European investigation of the microbial qualitative and quantitative aspects of DUWS.

RESULTS

Microbial loads ranged from 100 to 104 cfu ml-1 and exceeded the European guidelines for drinking water in many cases. The available evidence suggested the presence of isolates most likely belonging to families of aquatic and soil bacteria. It was not possible to draw distinct conclusions correlating microbial loads with dental unit parameters, including age of the unit, water source and chemistry and presence or absence of anti-retraction devices. Opportunistic or true pathogens were not detected. Yeasts were observed in samples from three units although further analysis confirmed that these were not Candida albicans. A decontamination strategy applied to one of the units eliminated the yeasts completely.

CONCLUSIONS

Dental practitioners must be knowledgeable regarding microbial contamination and biofilm formation in dental unit waterlines. There is a need for development of European evidence-based guidelines and reliable control regimes for microbial contamination of DUWS.

Heterologous expression of lactose- and galactose-utilizing pathways from lactic acid bacteria in Corynebacterium glutamicum for production of lysine in whey

The genetic determinants for lactose utilization from Lactobacillus delbrueckii subsp. bulgaricus ATCC 11842 and galactose utilization from Lactococcus lactis subsp. cremoris MG 1363 were heterologously expressed in the lysine-overproducing strain Corynebacterium glutamicum ATCC 21253. The C. glutamicum strains expressing the lactose permease and beta-galactosidase genes of L. delbrueckii subsp. bulgaricus exhibited beta-galactosidase activity in excess of 1000 Miller units/ml of cells and were able to grow in medium in which lactose was the sole carbon source. Similarly, C. glutamicum strains containing the lactococcal aldose-1-epimerase, galactokinase, UDP-glucose-1-P-uridylyltransferase, and UDP-galactose-4-epimerase genes in association with the lactose permease and beta-galactosidase genes exhibited beta-galactosidase levels in excess of 730 Miller units/ml of cells and were able to grow in medium in which galactose was the sole carbon source. When grown in whey-based medium, the engineered C. glutamicum strain produced lysine at concentrations of up to 2 mg/ml, which represented a 10-fold increase over the results obtained with the lactose- and galactose-negative control, C. glutamicum 21253. Despite their increased catabolic flexibility, however, the modified corynebacteria exhibited slower growth rates and plasmid instability.