Bacteriological Survey of Fresh Minced Beef on Sale at Retail Outlets in Scotland in 2019: Three Foodborne Pathogens, Hygiene Process Indicators, and Phenotypic Antimicrobial Resistance

ABSTRACT

The health and economic burden of foodborne illness is high, with approximately 2.4 million cases occurring annually in the United Kingdom. A survey to understand the baseline microbial quality and prevalence of food-related hazards of fresh beef mince on retail sale could inform risk assessment, management, and communication to ensure the safety of this commodity. In such a survey, a two-stage sampling design was used to reflect variations in population density and the market share of five categories of retail outlets in Scotland. From January to December 2019, 1,009 fresh minced beef samples were collected from 15 geographic areas. The microbial quality of each sample was assessed using aerobic colony count and Escherichia coli count. Samples were cultured for Campylobacter and Salmonella, and PCR was used to detect target genes (stx1 all variants, stx2 a to g, and rfbO157) for Shiga toxin-producing E. coli (STEC). The presence of viable E. coli O157 and STEC in samples with a positive PCR signal was confirmed via culture and isolation. Phenotypic antimicrobial sensitivity patterns of cultured pathogens and 100 E. coli isolates were determined, mostly via disk diffusion. The median aerobic colony count and E. coli counts were 6.4 × 105 (interquartile range, 6.9 × 104 to 9.6 × 106) and <10 CFU/g (interquartile range, <10 to 10) of minced beef, respectively. The prevalence was 0.1% (95% confidence interval [CI], 0 to 0.7%) for Campylobacter, 0.3% (95% CI, 0 to 1%) for Salmonella, 22% (95% CI, 20 to 25%) for PCR-positive STEC, and 4% (95% CI, 2 to 5%) for culture-positive STEC. The evidence for phenotypic antimicrobial resistance detected did not give cause for concern, mainly occurring in a few E. coli isolates as single nonsusceptibilities to first-line active substances. The low prevalence of pathogens and phenotypic antimicrobial resistance is encouraging, but ongoing consumer food safety education is necessary to mitigate the residual public health risk.

HIGHLIGHTS

1150 A Painless Anterior Chest Wall Mass Post Coronary Artery Bypass Grafting Surgery

Aim

We aim to present here a case of a painless anterior chest wall mass which was first noted during routine follow up post coronary artery bypass graft surgery

Case presentation

An 80-year-old male developed an asymptomatic slow growing pronounced swelling over the right anterior chest wall post CABG. His other past medical history includes chronic obstructive pulmonary disease, pulmonary fibrosis, ischaemic heart disease, an AICD for complete heart block, hypertension, hyperlipidaemia and osteoarthritis. A CT scan demonstrated a 10 x 12 x 6.5 cm subcutaneous lesion at the mid-line of the lower chest wall adjacent to the xiphisternum and the previous sternotomy site. On clinical examination there was a large non-tender cystic swelling with peripheral calcifications, but overlying skin was normal. Fluid was aspirated from the lesion and cytology showed a paucicellular specimen with features in keeping with seroma. Due to the progressive increase in size patient underwent surgical resection. A gelatinous bloody fluid was aspirated from the lesion and it was then resected enbloc. The tumour base appeared to arise from 6/7th costal cartilage and tumour was shaved away. The mass was confirmed histologically to be chondrosarcoma.

Conclusions

Given the uncommon prevalence of malignant primary chest wall tumours this case highlights the importance of high clinical suspicion even after developing post CABG.

Two centres experience of lung cancer resection in patients with advanced non-small cell lung cancer upon treatment with immune checkpoint inhibitors: safety and clinical outcomes

OBJECTIVES

Recent trials have begun to explore immune checkpoint inhibitors for non-small cell lung cancer in the neoadjuvant setting, but data on tumour response and surgical outcome remain limited.

METHODS

Retrospective evaluation of clinical data from patients with non-small cell lung cancer treated with immune checkpoint inhibitors followed by lung resection was performed at 2 large volume institutions (1 North American, 1 European). Data were analysed using Chi-squared, Fisher's and Wilcoxon rank-sum tests where appropriate.

RESULTS

Thirty-seven patients were identified from 2017 to 2019. Forty-nine per cent were Stage IIIB and IV. Forty-six per cent received immunotherapy alone and 54% in combination with chemo- and/or radiotherapy. Sixteen per cent of cases were successfully performed minimally invasively. Twenty patients were operated with lobectomy (6 of these with wedges or segments of a neighbouring lobe, 2 with sleeve resections and 1 with a chest wall resection), 4 with bilobectomies, 11 with pneumonectomy (including 5 extrapleural pneumonectomies and 1 atrial resection) and 1 with a wedge resection. Overall, 10 patients (27%) developed postoperative complications and the 90-day mortality was zero. One-year recurrence-free survival was 73% for stage II/IIIA and 55% for stage IIIB/stage IV. The major pathologic response rate was 34%.

CONCLUSION

In this retrospective study, lung resection after immunotherapy (alone or in combination) is safe, although often requires complex surgery. Due to increasing number of clinical trials adopting immunotherapy in the neoadjuvant setting, it is likely that this therapy will become part of standard of care. Immunotherapy may also allow surgery to have a role for selected patients with advanced disease.

Endoscopic Stent Insertion versus Primary Operative Management for Spontaneous Rupture of the Esophagus (Boerhaave Syndrome): An International Study Comparing the Outcome

Spontaneous rupture of the esophagus (Boerhaave syndrome) is an extremely rare, life-threatening condition. Traditionally surgery was the treatment of choice. Endoscopic stent insertion offers a promising alternative. The aim of this study was to compare the results of primary surgical therapy with endoscopic stenting. A British and a German high-volume center for esophageal surgery participated in this retrospective study. At the British center, operative therapy (primary repair or surgical drainage) was routinely carried out. Endoscopic stent insertion was the primary treatment option at the German center. Only patients with nonmalignant, spontaneous rupture of the esophagus (Boerhaave syndrome) were included. Demographic characteristics, comorbidity, clinical course, and outcome were analyzed. The study comprises 38 patients with a median age of 60 years. Time between rupture and treatment was less than 24 hours in 22 patients. Overall mortality was four of 38. Diagnosis greater than 24 hours was associated with higher risk for fatal outcome (odds ratio [OR], 4.64; 95% confidence interval [CI], 0.33 to 265.79). The surgery (S) and the endoscopic stent group (E) included 20 and 13 cases, respectively. Esophagectomy was unavoidable in three cases and two were managed conservatively. There were no significant differences in age, time to diagnosis less than 24 hours, intensive care unit days, hospital stay, sepsis, renal failure, slow respiratory weaning, or presence of comorbidity between the two groups. In 11 of 13 in the stent group, operative intervention (video-assisted thoracic surgery, thoracotomy, mediastinotomy) was eventually mandatory and three of 13 even required repeated surgery. The rate of reoperation in the surgery group was six of 20. Mortality was two of 13 (E) versus one of 20 (S). The odds for fatal outcome were 3.3 times higher in the stent group than in the surgery group (OR, 3.32; 95% CI, 0.15 to 213.98). Management of Boerhaave syndrome by means of endoscopic stent insertion offers no advantage regarding morbidity, intensive care unit or hospital stay, and is associated with frequent treatment failure eventually requiring surgical intervention. Furthermore, endoscopic stenting shows a higher risk for fatal outcome than primary surgical therapy.

Variation between hospitals in outcomes following cardiac surgery in the UK

INTRODUCTION

We examine the influence of variations in provision of cardiac surgery in the UK at hospital level on patient outcomes and also to assess whether there is an inequality of access and delivery of healthcare. Cardiothoracic surgery has pioneered the reporting of surgeon-specific outcomes, which other specialties have followed. We set out to identify factors other than the individual surgeon, which can affect outcomes and enable other surgical specialties to adopt a similar model.

MATERIALS AND METHODS

A retrospective analysis of prospectively collected data of patient and hospital level factors between 2013 and 2016 from 16 cardiac surgical units in the UK were analysed through the Society for Cardiothoracic Surgery of Great Britain and Ireland and the Royal College of Surgeons Research Collaborative. Patient demographic data, risks factors, postoperative complications and in-hospital mortality, as well as hospital-level factors such as number of beds and operating theatres, were collected. Correlation between outcome measures was assessed using Pearson's correlation coefficient. Associations between hospital-level factors and outcomes were assessed using univariable and multivariable regression models.

RESULTS

Of 50,871 patients (60.5% of UK caseload), 25% were older than 75 years and 29% were female. There was considerable variation between units in patient comorbidities, bed distribution and staffing. All hospitals had dedicated cardiothoracic intensive care beds and consultants. Median survival was 97.9% (range 96.3-98.6%). Postoperative complications included re-sternotomy for bleeding (median 4.8%; range 3.5-6.9%) and mediastinitis (0.4%; 0.1-1.0%), transient ischaemic attack/cerebrovascular accident (1.7%; range 0.3-3.0%), haemofiltration (3.7%; range 0.8-6.8%), intra-aortic balloon pump use (3.3%; range 0.4-7.4%), tracheostomy (1.6%; range 1.3-2.6%) and laparotomy (0.3%; range 0.2-0.6%). There was variation in outcomes between hospitals. Univariable analysis showed a small number of positive associations between hospital-level factors and outcomes but none remained significant in multivariable models.

CONCLUSIONS

Variations among hospital level factors exists in both delivery of, and outcomes, following cardiac surgery in the UK. However, there was no clear association between these factors and patient outcomes. This negative finding could be explained by differences in outcome definition, differences in risk factors between centres that are not captured by standard risk stratification scores or individual surgeon/team performance.

High Risk Aortic Valve Replacement - The Challenges of Multiple Treatment Strategies with an Evolving Technology

OBJECTIVES

Deciding on the optimal treatment strategy for high risk aortic valve replacement is challenging. Transcatheter Aortic Valve implantation (TAVI) has been available in our centre as an alternative treatment modality for patients since 2008. We present our early experience of TAVI and SAVR (surgical Aortic Valve Replacement) in high risk patients who required SAVR because TAVI could not be performed.

METHODS

The database for Surgical aortic valve and Transcatheter aortic valve replacement referrals was interrogated to identify relevant patients.

RESULTS

Survival to hospital discharge was 95.5% in the forty five patients who had SAVR when TAVI was deemed technically unsuitable. One year survival was 86%.

CONCLUSION

Defining who is appropriate for TAVI or high risk SAVR is challenging and multidisciplinary team discussion has never been more prudent in this field of evolving technology with ever decreasing risks of surgery. The introduction of TAVI at our institution has seen a rise in our surgical caseload by approximately by 25%. Overall, the option of aortic valve intervention is being offered to more patients in general which is a substantial benefit in the treatment of aortic valve disease.

Spotlight on esophageal perforation: A multinational study using the Pittsburgh esophageal perforation severity scoring system

OBJECTIVE

The Pittsburgh group has suggested a perforation severity score (PSS) for better decision making in the management of esophageal perforation. Our study aim was to determine whether the PSS can be used to stratify patients with esophageal perforation into distinct subgroups with differential outcomes in an independent study population.

METHODS

In a retrospective study cases of esophageal perforation were collected (study-period, 1990-2014). The PSS was analyzed using logistic regression as a continuous variable and stratified into low, intermediate, and high score groups.

RESULTS

Data for 288 patients (mean age, 59.9 years) presenting with esophageal perforation (during the period 1990-2014) were abstracted. Etiology was spontaneous (Boerhaave; n = 119), iatrogenic (instrumentation; n = 85), and traumatic perforation (n = 84). Forty-three patients had coexisting esophageal cancer. The mean PSS was 5.82, and was significantly higher in patients with fatal outcome (n = 57; 19.8%; mean PSS, 9.79 vs 4.84; P < .001). Mean PSS was also significantly higher in patients receiving operative management (n = 200; 69%; mean PSS, 6.44 vs 4.40; P < .001). Using the Pittsburgh strata, patients were assigned to low PSS (≤2; n = 63), intermediate PSS (3-5; n = 86), and high PSS (>5; n = 120) groups. Perforation-related morbidity, length of stay, frequency of operative treatment, and mortality increased with increasing PSS strata. Patients with high PSS were 3.37 times more likely to have operative management compared with low PSS.

CONCLUSIONS

The Pittsburgh PSS reliably reflects the seriousness of esophageal perforation and stratifies patients into low-, intermediate-, and high-risk groups with differential morbidity and mortality outcomes.

Identification of an HLA-B*07 allele variant (B*0740) in the Chinese Han population

A novel HLA-B*07 allele, B*0740, has been identified by sequence-based typing (SBT) in the Chinese Han population. This new allele is identical to B*0705 and B*0706 for exons 2, 3, and 4, except for a single nucleotide at position 605 of codon 202 in exon 3 (AAG-->ATG) leading to an amino acid change from lysine to methionine. SBT was performed following allele separation using the Haploprep method. The serological equivalence of B*0740 to the B7 antigen did not change.

Identification and cellular localisation of voltage-operated calcium channels in immature rat testis

Sertoli cells regulate the spermatogenic process mainly through the secretion of a complex fluid into the lumen of the seminiferous tubules behind the blood-testis barrier, containing many of the essential proteins necessary for maintenance and maturation of male germ cells. Thus, the study of Sertoli cell secretory processes is strictly correlated with the understanding of the regulatory mechanisms of spermatogenesis. In this work the authors have explored the voltage-sensitive calcium channel variety in the immature rat testis, their localisation and distribution within the seminiferous epithelium and peritubular and interstitial tissues as well as the possible role in the control of Sertoli cell secretion. The results reported in this paper, obtained by in situ hybridisation, immunohistology of rat testicular sections and Western blot analysis of Sertoli cell plasma membranes, show that mammalian Sertoli cells express mRNA encoding for several voltage-operated calcium channel subunits and express such proteins on their surface. Experiments performed on Sertoli cell monolayers cultured in the presence of specific toxins indicate that both N and P/Q-type Ca(2+) channels are involved in the regulation of protein secretion.

T-type Ca2+ current properties are not modified by Ca2+ channel beta subunit depletion in nodosus ganglion neurons

At the molecular level, our knowledge of the low voltage-activated Ca2+ channel (T-type) has made little progress. Using an antisense strategy, we investigated the possibility that the T-type channels have a structure similar to high voltage-activated Ca2+ channels. It is assumed that high voltage-activated channels are made of at least three components: a pore forming alpha1 subunit combined with a cytoplasmic modulatory beta subunit and a primarily extracellular alpha2delta subunit. We have examined the effect of transfecting cranial primary sensory neurons with generic anti-beta antisense oligonucleotides. We show that in this cell type, blocking expression of all known beta gene products does not affect T-type current, although it greatly decreases the current amplitude of high voltage-activated channels and modifies their voltage dependence. This suggests that beta subunits are likely not constitutive of T-type Ca2+ channels in this cell type.

Distribution of alpha 1A, alpha 1B and alpha 1E voltage-dependent calcium channel subunits in the human hippocampus and parahippocampal gyrus

The distribution of voltage-dependent calcium channel subunits in the central nervous system may provide information about the function of these channels. The present study examined the distribution of three alpha-1 subunits, alpha 1A, alpha 1B and alpha 1E, in the normal human hippocampal formation and parahippocampal gyrus using the techniques of in situ hybridization and immunocytochemistry. All three subunit mRNAs appeared to be similarly localized, with high levels of expression in the dentate granule and CA pyramidal layer. At the protein level, alpha 1A, alpha 1B and alpha 1E subunits were differentially localized. In general, alpha 1A-immunoreactivity was most intense in cell bodies and dendritic processes, including dentate granule cells, CA3 pyramidal cells and entorhinal cortex pre-alpha and pri-alpha cells. The alpha 1B antibody exhibited relatively weak staining of cell bodies but stronger staining of neuropil, especially in certain regions of high synaptic density such as the polymorphic layer of the dentate gyrus and the stratum lucidum and radiatum of the CA regions. The alpha 1E staining pattern shared features in common with both alpha 1A and alpha 1B, with strong immunoreactivity in dentate granule, CA3 pyramidal and entorhinal cortex pri-alpha cells, as well as staining of the CA3 stratum lucidum. These findings suggest regions in which particular subunits may be involved in synaptic communication. For example, comparison of alpha 1B and alpha 1E staining in the CA3 stratum lucidum with calbindin-immuno-reactivity suggested that these two calcium channels subunits may be localized presynaptically in mossy fibre terminals and therefore may be involved in neurotransmitter release from these terminals.

The expression of neuronal voltage-dependent calcium channels in human cerebellum

Little is known about the comparative distribution of voltage-dependent calcium channel subtypes in normal human brain. Previous studies in experimental animals have predominantly focused on the regional expression of single alpha 1 genes. We describe the preparation of riboprobes and antisera specific for human alpha 1A, alpha 1B and alpha 1E subunits and their application in comprehensive mapping studies of the human cerebellum. Within the cerebellar cortex, these pore forming proteins were found to have differential localisations when examined in adjacent sections. The alpha 1A and alpha 1B subunits broadly colocalised and were both present, though at apparently different levels, in the molecular, Purkinje and granule cell layers whilst alpha 1E was predominantly expressed in Purkinje cells. In the dentate nucleus, an area which has received little attention in previous studies, alpha 1A was highly expressed in regions in which Purkinje cell nerve terminals form synapses with deep cerebellar neurones.

Recovery of antibody production after HIV infection in 'common' variable hypogammaglobulinaemia

A patient with a history of at least 10 years 'common' variable hypogammaglobulinaemia seroconverted to HIV-1 and became hypergammaglobulinaemic. The HIV isolated from his blood did not polyclonally activate B cells from normal donors. The mechanism of the hypergammaglobulinaemia is discussed.

Assessment of responses of normal human B lymphocytes to different isolates of human immunodeficiency virus: role of normal donor and of cell line used to prepare viral isolate

The effect of different HIV-1 isolates on normal human B lymphocyte function has been studied in vitro. Production of IgM and IgG was measured by ELISA using a "standard" non-T preparation of B cells depleted of macrophages and T cells (but not of low-density accessory cells, LDC). Only one (H9/CBL-4) of five different isolates induced polyclonal production of immunoglobulin. Apart from intrinsic differences between isolates, important inherent variables were shown to affect the response. One was the mix of cell types in the responding preparation of B cells. This was tested by examining the effects of HIV-1 isolates independently on the accessory function of LDC and on B cell function when the LDC were removed. Isolate H9/HTLV-IIIRf was nonstimulatory on a B cell preparation containing LDC and suppressive on LDC accessory function yet could enhance function of B cells when the LDC were depleted. Another variable was the donor of the normal B cells. The B cell response was consistent with each donor but varied greatly with different donors. Thus, no single explanation emerges for the hypergammaglobulinemia in some adult AIDS patients and for the hypogammaglobulinemia in some pediatric cases. Additionally, the cell lines used to propagate the virus particularly affected the assay of B cells depleted of LDC. Uninfected supernatants had different effects on the B cell function, and these host cell effects (perhaps by release of cytokines or other mediators) may be exacerbated in infected cell lines. Our data show the complexity of the abnormal B cell function in AIDS.

Role of retroviruses in acquired hypogammaglobulinaemia

Mononuclear cells were obtained from 42 patients with 'common variable' hypogammaglobulinaemia (CVH) and co-cultured with various cell lines in an attempt to isolate retroviruses. Cultures from only two patients showed evidence of a viral infection, although the virus could not be isolated and characterized in either. Despite the previous isolation of HIV's from two other CVH patients, this data suggests that similar viruses are not etiologically involved in the majority of patients.

Type A behavior as a function of reversed computer activity

Four consecutive trials involving a computer activity were presented to 110 students categorized as Type A+, A-, B+, or B- personalities. A fifth trial presented the same computer activity with controls in reversed position, and Type A groups had more difficulty than Type B groups.

Isolation of retroviruses from two patients with "common variable" hypogammaglobulinaemia

Retroviruses related to human T-lymphotropic virus III/lymphadenopathy-associated virus (HTLV-III/LAV) have been isolated from peripheral-blood mononuclear cells of two patients with "common variable" hypogammaglobulinaemia who were being treated with intravenous gammaglobulin. One has had three different opportunistic infections. In both patients hypogammaglobulinaemia developed within 6 years of a longlasting undiagnosed viral-like illness in adolescence, and it is suggested that the virus causing that illness also gave rise to the hypogammaglobulinaemia. However, iatrogenic infection from intravenous gammaglobulin cannot be ruled out.