A cross-sectional survey of women's views and preferences for preterm birth screening and treatment

OBJECTIVES

Primary outcomes were to determine; 1) the desire for more patient information from healthcare professionals on preterm birth (PTB) prevention 2) the desire for PTB screening surveillance or participation in research or 3) the acceptability of transvaginal ultrasound (TVUS) or vaginal examinations to predict spontaneous PTB.

METHODS

A 19-question, piloted, self-administered survey was completed by unselected pregnant women in a tertiary maternity hospital in Dublin, Ireland. Data was collected to include maternal socio-demographics, past obstetric history, and current pregnancy details, in addition to views and preferences on PTB screening and preventative treatments. Statistical analysis to include binary and multinomial regression was performed by IBM SPSS Statistics for Windows (Version 29.0).

RESULTS

277 women completed the study survey. 9.4% of women had attended the preterm birth surveillance clinic (PSC). 75.1% of respondents indicated a preference for more information from healthcare professionals about PTB. 65% reported that TVUS and vaginal examinations were acceptable in pregnancy. The acceptability of antenatal examinations was significantly influenced by ethnicity; white European (OR 2.58, CI 1.12-5.95, p = 0.003) and Asian (OR 3.39, CI 1.18-9.67, p = 0.02). Discomfort (25.3%) and vaginal bleeding (11.9%) were the most frequently reported concerns about TVUS. 95.7% of unselected women indicated that they would accept treatment to prevent PTB. Vaginal progesterone (53.8%) was preferred treatment compared to cervical cerclage (15.9%) or cervical pessary (16.6%). 55.6% of respondents stated they attend or wish to attend for additional appointments or research opportunities for PTB screening. Women with a previous PTB or second trimester miscarriage were more likely to attend or wish to attend for PTB screening (OR 3.23, CI 1.34-7.79, p = 0.009).

CONCLUSION

PTB is an important healthcare priority for pregnant women in Ireland. However, women require more information, counselling and reassurance about the utility and safety of TVUS in PSCs.

New insights for predicting surgery outcome in patients with temporal lobe epilepsy. A systematic review

Resective surgery is the treatment of choice for one-third of adult patients with focal, drug-resistant epilepsy. This procedure is associated with substantial clinical and cognitive risks. In clinical practice, there is no validated model for epilepsy surgery outcome prediction (ESOP). Meta-analyses on ESOP studies assessing prognostic factors report discrepancies in terms of study design. Our review aims to systematically investigate methodological and analytical aspects of studies predicting clinical and cognitive outcomes after temporal lobe epilepsy surgery. A systematic review of ESOP studies published between 2000 and 2022 from three databases (MEDLINE, Web of Science, and PsycINFO) was completed by following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. It yielded 4867 articles. Among them, 21 corresponded to our inclusion criteria and were therefore retained in the final review. The risk of bias was assessed using A Tool to Assess Risk of Bias and Applicability of Prediction Model Studies (PROBAST). Data extracted from the 21 studies were analyzed using narrative synthesis and descriptive statistics. Our findings show an increase in the use of multimodal datasets and machine learning analyses in recent ESOP studies, although regression remained the most frequently used approach. We also identified a more frequent use of network notions in recent ESOP studies. Nevertheless, several methodological issues were noted, such as small sample sizes, lack of information on the follow-up period, variability in seizure outcome, and the definition of neuropsychological postoperative change. Of 21 studies, only one provided a clinical tool to anticipate the cognitive outcome after epilepsy surgery. We conclude that methodological issues should be overcome before we move towards more complete models to better predict clinical and cognitive outcomes after epilepsy surgery. Recommendations for future studies to harness the possibilities of multimodal datasets and data fusion, are provided. A stronger bridge between fundamental and clinical research may result in developing accessible clinical tools.

47 FRAILTY: A QUALITATIVE STUDY EXPLORING THE PERCEPTIONS OF CCCUPATIONAL THERAPISTS IN IRELAND

Background

Ireland’s ageing population has resulted in an increasing number of frail older adults presenting to health and social care settings nationwide. Despite growing attention towards older adults’ and health professionals’ perspectives of frailty, the evidence base pertaining to occupational therapists is limited. This study aims to explore occupational therapists’ perceptions of frailty within an Irish context and to investigate whether their perceptions subsequently impact their approach to the assessment and management of frailty.

Methods

A qualitative descriptive design was undertaken to explore the perceptions of frailty of occupational therapists working with older adults. Qualitative data was collected from nineteen (n=19) occupational therapists working across Ireland in various clinical settings participating in four online focus groups. Data were analysed using thematic analysis.

Results

Perceptions of occupational therapists were constructed into three main themes; 1) Conceptualising frailty; 2) Management of frailty; 3) Advancing frailty practice. Occupational therapists in Ireland shared similar perceptions of frailty as a multidimensional concept. Findings suggest that although occupational therapists are well-equipped in the provision of care for frail older adults, participants believed that the profession’s scope is not optimised in the assessment and management of frailty.

Conclusion

This study is the first of its kind to be conducted in Ireland, therefore contributing to the growing frailty research field. Development of community services, the enhancement of undergraduate frailty education, and a movement towards a shared understanding of frailty between clinicians and patients are recommended to progress occupational therapy in the context of frailty management.

Effect of plasma rich in growth factors on quality of life following mandibular third molar removal: a double-blind randomized controlled trial

The objective of this study was to investigate the effect of plasma rich in growth factors (PRGF) on patient- and clinician-reported outcomes following mandibular third molar removal. Seventy-four patients requiring surgical removal of a unilateral impacted mandibular third molar under local anaesthesia were recruited into the study. PRGF was prepared for all patients irrespective of study arm allocation. Reviews were conducted 3 days (T1) and 7 days (T2) postoperatively. Primary outcome measures were pain (numerical rating scale, NRS), OHIP-14 (Oral Health Impact Profile-14), and postoperative symptom severity scale (PoSSe) data. Secondary outcome measures including mouth opening, dry socket, socket healing, and analgesic consumption were also explored. The statistical analysis was performed using analysis of covariance and the χ² test. NRS pain scores were higher in the PRGF group at T1, demonstrating borderline significance (mean difference 1.0; P = 0.06), with no difference at T2. PoSSe scores did not differ between the groups, with the exception of the 'interference with daily activities' subscale at T1, where PRGF group patients scored 1.2 units higher (P = 0.02). OHIP-14 scores demonstrated a 25% increased likelihood of PRGF patients reporting discomfort on eating at T1 (P = 0.02), with no statistical significance at T2. Secondary outcomes did not differ between the groups. No difference in clinical or quality of life outcomes was observed for patients receiving adjunctive PRGF in third molar sockets.

SARS-CoV-2 Testing and Patient Waiting Times in the Emergency Department

Aim Emergency Departments (EDs) were impacted early in the coronavirus disease 2019 (COVID-19) pandemic, with high attendance numbers. EDs relied upon SARS-CoV-2 reverse-transcriptase polymerase chain reaction (RT-PCR) tests to triage patients and facilitate admission to appropriate wards, meaning positive patients were isolated as early as possible. In October 2020, we introduced a 24-hour SARS-CoV-2 testing service. We examined the impact of this on patient experience times (PETs) in the ED, and on healthcare-associated (HA) COVID-19 infections. Methods Data on PETs before and after the introduction of 24-hour testing were available from the ED. HA COVID-19 infections were reported weekly to the Health Services Executive as a key performance indicator. Results Mean PET prior to the pandemic was 20 hours and dropped to 10 and 13 hours respectively in the first and second wave. A surge in case numbers and ED attendances during the third wave was not reflected in a rise in PETs, with a mean PET of 11 hours, significantly below pre-pandemic levels. HA-COVID-19 infections remained stable between wave one and three (83 v 92). Conclusion The introduction of 24-hour SARS-CoV-2 testing in our ED contributed to a reduction in PETs, facilitated appropriate patient placement at ward level, and kept HA-COVID-19 infections at acceptably low levels.

O-295 Passive sperm sorting does not select for sperm with lower DNA fragmentation levels compared to density gradient centrifugation in split samples

Study question

Does the passive sperm separation device, Zymot, select sperm with lower DNA fragmentation levels compared to Density Gradient Centrifugation (DGC)?

Summary answer

The sperm separation device Zymot did not select sperm with lower DNA fragmentation levels compared to sperm selected by DGC or the neat sample.

What is known already

Previous studies have shown that sperm with high DNA fragmentation levels result in lower fertilisation rates, impaired embryo development, lower pregnancy rates and increases the risk of miscarriage. Currently, prior to fertility treatment, the method of choice for sperm selection is using DGC, which involves the centrifugation of sperm. Therefore, there is a clinical need for a sperm selection method that avoids centrifugation, while mimicking the natural process of sperm selection in the female reproductive tract and selects sperm with intact DNA.

Study design, size, duration

This blinded controlled study included 29 patients from which semen samples were obtained between May 2021- January 2022 at ReproMed fertility clinic (Dublin, Ireland). Ejaculates were split and processed using either DGC, passive separation device (Zymot; 850 uL) or unprocessed (neat; control) and assessed for sperm quality in terms of motility (progressive, non-progressive and immotile), morphology and DNA fragmentation (assessed using the COMET assay). Two hundred sperm were assessed for each analysis.

Participants/materials, setting, methods

Motility and morphology were assessed using microscopy techniques as per WHO guidelines. DNA fragmentation was assessed using the COMET assay and each sample was given an Average COMET score (ACS), Low COMET score (LCS) and High COMET score (HCS). All data were checked for normality of distribution following which they were analysed using analysis of variance (ANOVA) with Bonferroni post-hoc tests. All values presented are mean ± standard error of the mean.

Main results and the role of chance

Sperm sorted by the Zymot device had higher progressive motility (78.7 + 3.42%) than both the neat (53.3 + 3.40%) and DGC (51.8 + 3.74%%) samples (P < 0.001). Sperm selected by DGC had a greater percentage of sperm with non-progressive motility (16.0 + 2.02%) compared to the neat sample (8.6 + 1.11%) and the Zymot device (9.9 + 1.60%). The overall percentage of normal morphology in the neat sample was 4.3 + 0.16% and there was no effect of sperm selection method on the percentage of sperm with normal morphology (P > 0.05). The ACS in the neat sample was 32.5 + 1.48% and neither DGC (28.2 + 1.45%) or Zymot (29.1 + 1.50%) improved this (P > 0.05). In line with this, neither LCS nor HCS differed between the treatments (P > 0.05).

Limitations, reasons for caution

A higher number of patient samples are needed to validate the efficacy of the Zymot sperm separation device on DNA fragmentation levels. Also, targeting patients with higher DNA fragmentation in the neat sample may yield greater benefits.

Wider implications of the findings

The results of this study indicate that the passive sperm selection device, Zymot, selects more motile sperm but does not select sperm with intact DNA. There is a need for a non-cell destructive method to select sperm with intact DNA to improve the outcomes for couples undergoing fertility treatment.

Trial registration number

Not Applicable

Assessment of the microbial load of airway clearance devices used by a cohort of children with cystic fibrosis

Background

Positive expiratory pressure (PEP) devices are an important element of the management of cystic fibrosis, and of other respiratory diseases. Whereas there have been reports in the literature of contamination of airway clearance devices and their surfaces by microbial pathogens, there is little evidence available regarding such contamination and its contribution to respiratory infection.

Aim

To establish whether pathogenic bacteria can contaminate PEP devices in the context of normal cleaning and maintenance practices.

Methods

Patients' home-use clearance devices were brought to a routine clinic appointment and collected for microbiology sampling and analysis. The patients were provided with replacement devices. Nineteen such devices were collected from 17 patients, reflecting use of multiple devices by some patients. Swabs were taken and cultured from each patient's used device, the patient's airway, as well as from new unopened and unused devices that acted as controls.

Results

Seven of 19 devices (37%) tested positive for presence of pathogenic bacteria. Device-cleaning methods varied among patients and non-sterilization methods were found to be ineffective at removing pathogens. Microbial species found on the devices did not correlate with those identified from airway swabs.

Conclusion

This study demonstrates the presence of pathogens on positive expiratory pressure devices. The potential for transmission of these pathogens to the patient's airway and the risk of infection remains unclear and requires further study.

Field scale estimates of soil carbon stocks on ten heavy textured farms across Ireland

The world's soils store vast amounts (≈2,500 GT) of Carbon which acts as a vital sink to counterbalance the effects of increasing atmospheric carbon dioxide. There have been fruitful efforts to quantify soil Carbon stocks at national scales, which are required for policy level decisions but lack the high resolution required to support farm specific decisions. It is hypothesised that farm scale evaluations of soils can provide insight that is masked in national scale studies and can allow for spatially explicit management approaches to optimise soil Carbon storage and sequestration, such that it can be prioritized within profitable production systems. The objective of the present study was to estimate Carbon stocks on a range of heavy textured soils at field and farm scale and to quantify Carbon storage relative to national scale estimates. Ten grassland dairy farms (mean area of 52.2 Ha) were surveyed, sampled and classified to determine soil types and quantify soil Carbon stores. The level of Carbon present (mean: 346.0 T/Ha) at these sites was greater than previous averages on such soils quantified at national scale (by a factor of 1.1-3.9 depending on soil type). Furthermore, if Carbon saturation potential was realised, the amount of Carbon stored could be increased by an average of 792.1 T/Ha in each profile (from 346.0 to 1138.1 T/Ha). Current management has fostered the retention of large stores of soil Carbon on such soils/farms which co-exist within highly productive farm systems. As there is a societal demand to retain and enhance soil carbon stores to mitigate climate change, high Carbon soils should be identified and, under appropriate policies, commodified to offer a direct incentive to retain soil Carbon. The value of this resource should be recognised and polices to ensure a spatially explicit approach for soil Carbon management should be adopted.

Search for Electron Antineutrino Appearance in a Long-Baseline Muon Antineutrino Beam

Electron antineutrino appearance is measured by the T2K experiment in an accelerator-produced antineutrino beam, using additional neutrino beam operation to constrain parameters of the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix. T2K observes 15 candidate electron antineutrino events with a background expectation of 9.3 events. Including information from the kinematic distribution of observed events, the hypothesis of no electron antineutrino appearance is disfavored with a significance of 2.40σ and no discrepancy between data and PMNS predictions is found. A complementary analysis that introduces an additional free parameter which allows non-PMNS values of electron neutrino and antineutrino appearance also finds no discrepancy between data and PMNS predictions.

Bacteriophages in Food Applications: From Foe to Friend

Bacteriophages (phages) have traditionally been considered troublesome in food fermentations, as they are an important cause of starter-culture failure and trigger significant financial losses. In addition, from an evolutionary perspective, phages have contributed to the pathogenicity of many bacteria through transduction of virulence genes. In contrast, phages have played an important positive role in molecular biology. Moreover, these agents are increasingly being recognized as a potential solution to the detection and biocontrol of various undesirable bacteria, which cause either spoilage of food materials, decreased microbiological safety of foods, or infectious diseases in food animals and crops. The documented successful applications of phages and various phage-derived molecules are discussed in this review, as are many promising new uses that are currently under development.

Search for CP Violation in Neutrino and Antineutrino Oscillations by the T2K Experiment with 2.2×10^{21} Protons on Target

The T2K experiment measures muon neutrino disappearance and electron neutrino appearance in accelerator-produced neutrino and antineutrino beams. With an exposure of 14.7(7.6)×10^{20} protons on target in the neutrino (antineutrino) mode, 89 ν_{e} candidates and seven anti-ν_{e} candidates are observed, while 67.5 and 9.0 are expected for δ_{CP}=0 and normal mass ordering. The obtained 2σ confidence interval for the CP-violating phase, δ_{CP}, does not include the CP-conserving cases (δ_{CP}=0, π). The best-fit values of other parameters are sin^{2}θ_{23}=0.526_{-0.036}^{+0.032} and Δm_{32}^{2}=2.463_{-0.070}^{+0.071}×10^{-3}  eV^{2}/c^{4}.

Comparative genomics of Cp8viruses with special reference to Campylobacter phage vB_CjeM_los1, isolated from a slaughterhouse in Ireland

Campylobacter phage vB_CjeM_Los1 was recently isolated from a slaughterhouse in the Republic of Ireland using the host Campylobacter jejuni subsp. jejuni PT14, and full-genome sequencing and annotation were performed. The genome was found to be 134,073 bp in length and to contain 169 predicted open reading frames. Transmission electron microscopy images of vB_CjeM_Los1 revealed that it belongs to the family Myoviridae, with tail fibres observed in both extended and folded conformations, as seen in T4. The genome size and morphology of vB_CjeM_Los1 suggest that it belongs to the genus Cp8virus, and seven other Campylobacter phages with similar size characteristics have also been fully sequenced. In this work, comparative studies were performed in relation to genomic rearrangements and conservation within each of the eight genomes. None of the eight genomes were found to have undergone internal rearrangements, and their sequences retained more than 98% identity with one another despite the widespread geographical distribution of each phage. Whole-genome phylogenetics were also performed, and clades were shown to be representative of the differing number of tRNAs present in each phage. This may be an indication of lineages within the genus, despite their striking homology.

Bacteriophage-based tools: recent advances and novel applications

Bacteriophages (phages) are viruses that infect bacterial hosts, and since their discovery over a century ago they have been primarily exploited to control bacterial populations and to serve as tools in molecular biology. In this commentary, we highlight recent diverse advances in the field of phage research, going beyond bacterial control using whole phage, to areas including biocontrol using phage-derived enzybiotics, diagnostics, drug discovery, novel drug delivery systems and bionanotechnology.

A Quality Improvement Approach to Reducing the Caesarean section Surgical Site Infection Rate in a Regional Hospital

Surgical site infection (SSI) rates are used extensively by hospitals as a basis for quality improvement. A 30-day post-discharge SSI programme for Caesarean section operations has been implemented in Our Lady of Lourdes Hospital since 2011. It has been shown that skin antisepsis and antibiotic prophylaxis are key factors in the prevention of SSI. Using quality improvement methodology, an infection prevention bundle was introduced to address these two factors. Skin antisepsis was changed from povidone-iodine to chlorhexidine-alcohol. Compliance with choice of antibiotic prophylaxis increased from 89.6% in 2014 to 98.5% in 2015. Compliance with timing also improved. The SSI rate of 7.5% was the lowest recorded to date, with the majority of SSIs (64%) diagnosed after hospital discharge. The level of variation was also reduced. However, the continued presence of variation and possibility of lower infection rates from the literature imply that further improvements are required.

The neonatal gut harbours distinct bifidobacterial strains

BACKGROUND

Recent studies have described the bifidobacterial composition of neonates at a species level; however, with advancing technologies we can gain insight into the diversity of the bifidobacterial microbiota residing within the infant gut.

OBJECTIVE

To compare species and strain diversity of culturable bifidobacterial populations in faecal samples obtained from healthy term infants on three different feeding regimes.

STUDY DESIGN

In total, 51 healthy term infants were recruited for this study and divided equally into three different groups (n=17) based on their feeding regime during the first 4 weeks of life. Culturable bifidobacterial populations were analysed at week 1, week 4 and 6 months of age. Isolates were characterised to species level by 16s rRNA-internally transcribed spacer (ITS) gene sequence analysis and to strain level by pulsed field gel electrophoresis (PFGE).

RESULTS

In total,173 bifidobacterial strains were detected across all three groups from 2295 isolates, 42% (72 of 173) of which were detected in the prebiotic-fed group, followed by 30% (52 of 173) and 28% (49 of 173) in the breastfed and non-prebiotic-fed groups, respectively. Surprisingly, only two of the 51 infants harboured an identical bifidobacterial strain which was not present in the other 49 infants. Prebiotic supplementation in the early neonatal period increased the prevalence of Bifidobacterium longum in infants, in addition to promoting strain diversity. B. longum was the dominant species recovered from all three groups during the first 6 months of life, followed by Bifidobacterium breve and Bifidobacterium bifidum.

CONCLUSIONS

This study reveals a hitherto unknown level of diversity at the strain level among bifidobacteria isolated from different infants and the influence prebiotic formula feeding has on the bifidobacterial population.

Two Australian Fetuses: Frederic Wood Jones and the Work of an Anatomical Specimen

A close analysis of two fetal specimens is used to explore of role of material specimens in anatomical practice of the late nineteenth and early twentieth centuries, the significance of Indigenous bodies in that era's quest for an understanding of human difference, and the postcolonial legacies of the global project of creating collections of human specimens.

Maternal corticosterone exposure in the mouse has sex-specific effects on placental growth and mRNA expression

Maternal exposure to increased synthetic glucocorticoids (GC) during pregnancy is known to disturb fetal development and increase the risk of long-term disease. Maternal exposure to elevated levels of natural GC is likely to be common yet is relatively understudied. The placenta plays an important role in regulating fetal exposure to maternal GC but is itself vulnerable to maternal insults. This study uses a mouse model of maternal corticosterone (Cort) exposure to investigate its effects on the developing placenta. Mice were treated with Cort (33 μg/kg·h) for 60 h starting at embryonic d 12.5 (E12.5) before collection of placentas at E14.5 and E17.5. Although Cort exposure did not affect fetal size, placentas of male fetuses were larger at E17.5 in association with changes in placental Igf2. This increase in size was associated with an increase in placental thickness and an increase in placental junctional zone volume. Placentas from female fetuses were of normal size and had no changes in growth factor mRNA levels. The expression of the protective enzyme 11β-hydroxysteroid dehydrogenase type 2 was increased at E14.5 but was decreased in males at E17.5. In contrast, the expression of Nr3c1 (which encodes the GC receptor) was increased during the Cort exposure and remained elevated at E17.5 in the placentas of male fetuses. Our study has shown that maternal Cort exposure infers a sex-specific alteration to normal placental growth and growth factor expression, thus further adding to our understanding of the mechanisms of male dominance of programmed disease.

The time and place of nostalgia: re-situating a French disease

The history of nostalgia as a clinical category has many highly specific national stories. This paper traces an aspect of this history, examining aspects of nostalgia's changing meanings in nineteenth-century France. Nostalgia was a disease triggered by displacement, which became medically and politically important after the French Revolution, when military surgeons encountered epidemics of nostalgia in the armed forces. Understood as a form of pathological homesickness, the category straddled environmental medicine and emerging ideas about insanity. The diagnosis became particularly important to Idéologue writers as a case study in regulating and redirecting the emotions, demonstrating the efficacy of their new "moral" treatments and an ability to generate patriotic attachment to the new nation state. Over the course of the century, nostalgia disintegrated as a medical condition reflecting a decline in environmental explanations for disease within medicine, and increasingly plastic meanings attached to nostalgic desire.

Cross channel infections: nostalgia, spleen and the construction of national character

In the nineteenth century, both spleen and nostalgia were considered clinical categories, and each associated with the character of a nation. English medical commentators boasted of their compatriots' resistance to nostalgia, an often fatal form of homesickness, while the French in turn argued that the splenetic English were flocking to France to escape their own insalubrious climate. Behind such jingoistic claims were broader concerns, on both sides of the channel but particularly acute for the French, about the impact of modernity on subjectivity, the relation between home, homeland and empire, and the fitness of both nations to succeed in the modern age.

Micellarisation of carotenoids from raw and cooked vegetables

The efficiency of carotenoid micellarisation from plant foods can be used as an effective tool for the initial screening of carotenoid bioavailability. Therefore, the objectives of the present study were to assess the effects of cooking on the micellarisation of beta-carotene, lycopene, beta-cryptoxanthin and lutein from courgette (zucchini), red pepper and tomato; and, to a minor extent, investigate uptake of lutein by Caco-2 cells from micellar fractions obtained from raw and cooked courgettes. Both raw and cooked vegetables were subjected to an in vitro digestion procedure. beta-Carotene levels were significantly decreased in the digesta from each vegetable after boiling, grilling, microwave-cooking, or steaming, however all of the cooking methods enhanced beta-carotene transfer to micelles. Carotenoid micellarisation ranged from 1.7% to 100% depending on the food, carotenoid, and the cooking method tested. Grilling and microwave-cooking were generally the most detrimental on the transfer of xanthophyll carotenoids, namely beta-cryptoxanthin, to the micelles. Caco-2 cells absorbed greater amounts of lutein from the micelles of microwave-cooked courgettes than those that were raw, boiled, grilled, or steamed. Depending on the cooking methods used, carotenoid retention as well as micellarisation varied for each carotenoid among the different vegetables and different carotenoids present in each particular food.

Evaluation of live-culture-producing lacticin 3147 as a treatment for the control of Listeria monocytogenes on the surface of smear-ripened cheese

AIMS

A live Lactococcus lactis culture, producing the two-component broad spectrum bacteriocin lacticin 3147, was assessed for ability to inhibit the food pathogen Listeria monocytogenes on the surface of smear-ripened cheese.

METHODS AND RESULTS

In initial experiments, the addition of Listeria to a lacticin 3147-containing fermentate produced with L. lactis DPC4275 (a transconjugant strain derived from L. lactis DPC3147) resulted in at least a 4 log reduction of the pathogen in 30 min. Two separate trials were performed in order to assess the most suitable method for application of the potential protective culture to smear-ripened cheese. In the initial trial, the L. lactis was sprayed onto the surface of the cheese either before or after Listeria was deliberately applied. Application of the culture following Listeria challenge, yielded up to a 1000-fold reduction of the pathogen in contrast to the pretreatment where Listeria numbers were unaffected. In a further trial, three applications of the live lacticin 3147-producing culture was used on a cheese surface containing Listeria. Listeria numbers were found to be up to 100-fold lower than in the cheese treated with L. lactis DPC4268 (control).

CONCLUSION

While application of the live lacticin 3147 producer did not give complete elimination of the pathogen the results nonetheless demonstrate the potential of the bioprotectant for improving the safety of smear-ripened cheeses and particularly those that contain low level contamination with Listeria.

SIGNIFICANCE AND IMPACT OF THE STUDY

The application of lacticin 3147 as a live-culture can serve as a bioprotectant for the control of L. monocytogenes on the surface of smear-ripened cheese.

A lacticin 481-producing adjunct culture increases starter lysis while inhibiting nonstarter lactic acid bacteria proliferation during Cheddar cheese ripening

AIMS

The main aim of this study was to exploit a lacticin 481 producing strain, Lactococcus lactis CNRZ481, as an adjunct for Cheddar cheese manufacture, to increase starter cell lysis and control nonstarter lactic acid bacteria (NSLAB) proliferation in cheese.

METHODS AND RESULTS

Lactococcus lactis CNRZ481 was exploited as an adjunct to L. lactis HP for the manufacture of Cheddar cheese at pilot scale (450 l). In these trials, inclusion of the adjunct strain did not compromise acid production by L. lactis HP and cheese was successfully manufactured within 5 h. Experimental cheese exhibited levels of lactate dehydrogenase (LDH) up to five-fold higher than control cheese and a significant reduction in NSLAB growth was also observed throughout the ripening period.

CONCLUSIONS

The aims of the study were accomplished as (i) greater enzyme release was achieved through lacticin 481-induced lysis which was associated with an improved flavoured cheese as assessed by a commercial grader and (ii) NSLAB growth was controlled, thus reducing the risk of off-flavour development.

SIGNIFICANCE AND IMPACT OF THE STUDY

The use of lacticin 481-producing adjuncts for cheese manufacture may prove beneficial for manufacturers who aim to achieve faster ripening through premature and elevated intracellular enzyme release while minimizing inconsistencies in cheese quality because of NSLAB activity.

Generation of food-grade lactococcal starters which produce the lantibiotics lacticin 3147 and lacticin 481

Transconjugant lactococcal starters which produce both lantibiotics lacticin 3147 and lacticin 481 were generated via conjugation of large bacteriocin-encoding plasmids. A representative of one of the resultant strains proved more effective at killing Lactobacillus fermentum and inhibiting the growth of Listeria monocytogenes LO28H than either of the single bacteriocin-producing parental strains, demonstrating the potential of these transconjugants as protection cultures for food safety applications.

Elevated enzyme release from lactococcal starter cultures on exposure to the lantibiotic lacticin 481, produced by Lactococcus lactis DPC5552

A Lactococcus lactis subsp. lactis strain (DPC5552), which causes the lysis of other lactococcal cultures, was isolated during a screening of raw milk samples for bacteriocin producers. Purification of the bacteriocin produced revealed that production of the lantibiotic, lacticin 481, was associated with the bacteriolytic capability of the strain. However, unlike bacteriocin-induced lysis observed with bacteriocins such as lacticin 3147 and lactococcins A, B, and M (where the target strain is killed), the DPC5552 supernatant gave rise to a situation whereby the target strain continued to grow (albeit at a lower rate) with simultaneous release of the intracellular enzymes lactate dehydrogenase (LDH) and post-proline dipeptidyl aminopeptidase (Pep X). In parallel experiments, 32 AU/ml of the inhibitory activity from L. lactis DPC5552 resulted in a 10- and 6-fold-higher LDH release after 5 h than that with 32 AU/ml of either lacticin 3147 or lactococcin A, B, and M. Laboratory-scale Cheddar cheese-making trials also demonstrated that lacticin 481-producing cultures induced the release of elevated levels of LDH from the starter L. lactis HP, without severely compromising its acid-producing capabilities. These results indicate that lacticin 481-producing strains may provide improved adjuncts for delivering lactococcal intracellular enzymes into the cheese matrix and, thus, improve cheese quality and flavor.

Use of lacticin 481 to facilitate delivery of the bacteriophage resistance plasmid, pCBG104 to cheese starters

AIMS

Use of lacticin 481 to facilitate the conjugal transfer of the bacteriophage resistance plasmid pCBG104 to various starter cultures.

METHODS AND RESULTS

A raw milk isolate of Lactococcus was found to harbour determinants for lacticin 481 production and immunity and phage resistance on a plasmid designated pCBG104. The lacticin 481 was successfully used to mobilize the phage resistance determinant to a variety of cheese starters enabling the formation of highly phage resistant starters. In addition, it facilitated the stacking of a number of phage resistance genes, namely a type I restriction modification system, a phage abortive infection system and a phage adsorption blocking system in a single Lactococcus strain without the use of recombinant techniques. The transconjugants were all shown to produce lacticin 481 and to contain the entire 481 operon. Subsequently one transconjugant was selected and successfully used for large-scale cheddar cheese manufacture.

CONCLUSIONS

Lacticin 481 could be used as a food-grade selectable marker to facilitate the introduction of advantageous traits to starter cultures for industrial food fermentations.

SIGNIFICANCE AND IMPACT OF THE STUDY

Food-grade selectable markers greatly facilitate the introduction of various advantageous traits to starter cultures for industrial food fermentation. Indeed self-cloning which is becoming increasingly important for strain improvement has a requirement for the identification and demonstration of the utility of tools such as lacticin 481.

Potential of bacteriocin-producing lactic acid bacteria for improvements in food safety and quality

Lactic acid bacteria (LAB) have been used for centuries in the fermentation of a variety of dairy products. The preservative ability of LAB in foods is attributed to the production of anti-microbial metabolites including organic acids and bacteriocins. Bacteriocins generally exert their anti-microbial action by interfering with the cell wall or the membrane of target organisms, either by inhibiting cell wall biosynthesis or causing pore formation, subsequently resulting in death. The incorporation of bacteriocins as a biopreservative ingredient into model food systems has been studied extensively and has been shown to be effective in the control of pathogenic and spoilage microorganisms. However, a more practical and economic option of incorporating bacteriocins into foods can be the direct addition of bacteriocin-producing cultures into food. This paper presents an overview of the potential for using bacteriocin-producing LAB in foods for the improvement of the safety and quality of the final product. It describes the different genera of LAB with potential as biopreservatives, and presents an up-to-date classification system for the bacteriocins they produce. While the problems associated with the use of some bacteriocin-producing cultures in certain foods are elucidated, so also are the situations in which incorporation of the bacteriocin-producer into model food systems have been shown to be very effective.

p21(WAF1) expression and endocrine response in breast cancer

An immunocytochemical assay for the p53-regulated protein product of the WAF1/Cip1 gene, p21(WAF1) (p21), was developed and applied to archival primary breast tumour material from 91 patients whose subsequent recurrent disease was treated with assessable courses of endocrine therapy. Nuclear localization of p21 protein was observed in 76 (82.4 per cent) cases. Status cut-offs were established and 29 (31.9 per cent) were deemed negative, 39 (42.9 per cent) weakly positive, and 23 (25.3 per cent) strongly positive. p21 status was inversely correlated with p53 protein (p=0.047) but did not relate to oestrogen receptor (ER) status, response to endocrine therapy, or time to further disease progression (TTP). Highly p21-positive patients had a significantly improved overall survival time (p=0. 020). Co-assessment of p21 and p53 subgroups revealed p21+/p53- patients to have good survival characteristics, whilst p21-/p53+ patients did poorly (p=0.008). The p21-/p53- patients overall did intermediately well, but Ki67-defined cellular proliferation analysis of these revealed two subclasses: those with high proliferation and poor survival times resembling the p21-/p53+ phenotype, and those with less proliferative tumours with good survival, similar to the p21+/p53- group. The significance of these results is discussed in the light of recent research concerning the role of p21 and p53 in breast cancer aetiology.

Reliability of the peroneal latency in normal ankles

The aim of this study was to determine the reliability of peroneal latency between trials and to compare the right and left sides in healthy subjects. A dual platform trapdoor was constructed to tilt the right or the left ankle by 30 degrees in the frontal plane. Electromyography recorded the onset of peroneal activity in response to this perturbation, and an accelerometer detected the onset of trapdoor movement. Peroneal latency was determined algorithmically as the time difference between the onset of trapdoor movement and the onset of peroneal activity. Twenty trials were recorded from 31 right leg dominant, healthy subjects. Peroneal latency was measured successfully for 613 trials (99% success rate). A repeated measures analysis of variance showed a main effect for side with the right, dominant side recording a longer latency. Intertrial reliability of the peroneal latency was high (intraclass correlation coefficients for the right and left legs were .91 and .82, respectively). Thus, peroneal latency is a reliable measure of the polysynaptic reflex ares involved in the response of these muscles to a sudden inversion stress.

Neuropsychological rehabilitation in the treatment of schizophrenia

The Schizophrenia Rehabilitation Center at the Institute of Living has begun to develop rehabilitation techniques based on a neuropsychological approach to ameliorate the cognitive deficits associated with schizophrenia. A study was designed to test the hypothesis that patients receiving attention skills training would demonstrate improved performance on neuropsychological tests measuring concentration. Five out of the seven subjects significantly improved on more than half of the neuropsychological measures. In the two case studies reviewed, significant increases in test scores were observed more frequently during cognitive rehabilitation then when psychoeducation classes were substituted for the attention skills training. In addition, patients showed improvement on the Positive and Negative Syndrome Scale and Quality of Life Scale. The data support the efficacy of attention skills training using a process specific approach. However, it is uncertain if attention skills rehabilitation is a necessary or sufficient factor in producing the therapeutic change.