Inactivation of Listeria monocytogenes by Hydrogen Peroxide Addition in Commercial Cheese Brines.

Commercial cheese brines are used repeatedly over extended periods, potentially for years, and can be a reservoir for salt-tolerant pathogens, such as Listeria monocytogenes. The objective of this study was to determine the inactivation of L. monocytogenes in cheese brines treated with hydrogen peroxide (H2O2) (0, 50, and 100 ppm) at holding temperatures representing manufacturing conditions. In experiment one, four fresh cheese brines were prepared with 10 or 20% salt and pH 4.6 or 5.4 (2x2 design; duplicate trials). Brines were inoculated with L. monocytogenes, treated with H2O2, and stored at 10 and 15.6°C. For experiment two, seven used commercial brines (representing five cheese types, 15-30% NaCl, pH 4.5-5.5; three seasonal trials) were inoculated with L. monocytogenes or S. aureus, treated with H2O2, and stored at 12.8°C (both L. monocytogenes and S. aureus), 7.2 and 0°C (L. monocytogenes only). Each treatment was assayed on Days 0, 1, and 7 for microbial populations and residual H2O2. Data revealed that pathogen populations decreased ≤1 log in cheese brines with no hydrogen peroxide stored for 7 days, regardless of the storage temperature. In fresh brine treated with 50 or 100 ppm of H2O2, populations of L. monocytogenes were reduced to less than the detectable limit by 7 days at 10 and 15.6°C (>4 log reduction). For unfiltered used brines, H2O2 had no effect on L. monocytogenes populations in Brick J (pH 5.4, 15% NaCl) due to rapid inactivation of H2O2, likely by indigenous yeasts (∼3-log CFU/ml). For the remaining brines, the addition of 100 ppm H2O2 killed >4 log L. monocytogenes when stored at 7.2 or 12.8°C for 1 week, but only 3-4 log reduction when stored at 0°C. The addition of 50 ppm H2O2 had similar lethal effects at 12.8°C but was less effective at 7.2 or 0°C. Inactivation rates of S. aureus were similar to that of L. monocytogenes. This study confirmed that high salt, warmer temperature, and 100-ppm H2O2 accelerated the inactivation of L. monocytogenes in cheese brines. Data also suggest that the presence of catalase-positive indigenous microorganisms may neutralize the effect of H2O2.

Discontinuation of Car Seat Tolerance Screening and Postdischarge Adverse Outcomes in Infants Born Preterm.

OBJECTIVE: To study the association between discontinuing predischarge car seat tolerance screening (CSTS) with 30-day postdischarge adverse outcomes in infants born preterm. STUDY DESIGN: Retrospective cohort study involving all infants born preterm from 2010 through 2021 who survived to discharge to home in a 14-hospital integrated health care system. The exposure was discontinuation of CSTS. The primary outcome was a composite rate of death, 911 call-triggered transports, or readmissions associated with diagnostic codes of respiratory disorders, apnea, apparent life-threatening event, or brief resolved unexplained events within 30 days of discharge. Outcomes of infants born in the periods of CSTS and after discontinuation were compared. RESULTS: Twelve of 14 hospitals initially utilized CSTS and contributed patients to the CSTS period; 71.4% of neonatal intensive care unit (NICU) patients and 26.9% of non-NICU infants were screened. All hospitals participated in the discontinuation period; 0.1% was screened. Rates of the unadjusted primary outcome were 1.02% in infants in the CSTS period (n = 21 122) and 1.06% after discontinuation (n = 20 142) (P = .76). The aOR (95% CI) was 0.95 (0.75, 1.19). Statistically insignificant differences between periods were observed in components of the primary outcome, gestational age strata, NICU admission status groups, and other secondary analyses. CONCLUSIONS: Discontinuation of CSTS in a large integrated health care network was not associated with a change in 30-day postdischarge adverse outcomes. CSTS's value as a standard predischarge assessment deserves further evaluation.

Evaluation of the impact of human immunodeficiency virus pre-exposure prophylaxis on new human immunodeficiency virus diagnoses during the COVID-19 pandemic.

AIMS: The national PrEP programme launched in Ireland in November 2019 with tenofovir/emtricitabine free to those meeting eligibility criteria. We assessed the impact of the first year of the PrEP programme on new HIV diagnoses in the largest sexual health and HIV service in Ireland. METHODS: A free PrEP service was established in November 2019. We reviewed the number of new diagnoses of HIV between November 2018-2019, before the introduction of the national PrEP programme and compared this with the number of new HIV diagnosis between November 2019-2020. RESULTS: There were 95 new HIV diagnoses (63.3% MSM) between November 2018 and 2019 and 73 new HIV diagnoses (65.7% MSM) between November 2019 and 2020. There was a statistically significant decline in new HIV diagnoses between the 2 years (P = 0.0003). 546 patients were prescribed PrEP as of December 2020.106 patients (19.4%) changed their PrEP dosing regimen due to lockdown. 178 individuals (32.6%) had a rectal infection diagnosed. CONCLUSION: There has been a reduction in new HIV diagnoses in our cohort (although this has occurred during a global pandemic). It is too early to say if PrEP reduces late presentations of HIV based on our findings. A significant number of rectal infections were identified in the PrEP clinic suggesting ongoing risk despite pandemic restrictions. Further research into sexual practices during COVID-19 is needed to assess if this had an impact on the lower rates of HIV acquisition.

Ten Bird Species, Six Guilds, Three Habitats, and 59 Chlorinated and Brominated POPs: What do 64 Eggs from the Largest Economic Hub of Southern Africa tell us?

There is little information on how POPs in eggs of different terrestrial, wetland, and aquatic birds share a large urban and rural landscape relate. We collected and analysed 64 eggs belonging to ten species of six feeding guilds, and compared organic chlorinated pesticide (OCP), polychlorinated biphenyl (PCB), and brominated flame retardants (BFR) residue concentrations and compositions. The eggs were collected in the Gauteng and the northern part of the Free Sate provinces of South Africa, one of the largest economic hubs in Africa. White-breasted Cormorant and African Darter eggs (at the highest trophic level as large aquatic predators) had the highest ΣOCP and ΣPCB concentrations, and Cape Sparrow and Southern Masked Weaver (granivores) eggs had the lowest concentrations, corresponding to the lowest trophic level in our collection. The highest percentage p,p'-DDT were in eggs of the terrestrial insectivore Crowned Lapwing (24%) and the scavenging African Sacred Ibis (17%), and the lowest in African Darter (1.0%) and White-breasted Cormorant (0.9%) eggs, suggesting that recency of DDT releases in a region cannot be gauged by this metric. African Sacred Ibis and Southern Masked Weaver eggs had the highest ΣBFR concentrations, with Crowned Lapwing, Cattle Egret, and White-breasted Cormorant eggs the least. Based on feeding guilds, the mean ΣPOP concentrations increased from granivore, aquatic omnivore, scavenger, terrestrial insectivore, small aquatic predator, to large aquatic predator. Mean ΣPOP concentrations in eggs increased from terrestrial, to wetland, to aquatic habitat birds. Interesting patterns were observed with multivariate analyses. There were no significant regressions between egg size and any summed POP classes. ΣBFR concentrations were not correlated with ΣOCPs or ΣPCBs. Eggshell thinning of African Darter eggs was associated with p,p'-DDE and ΣPCB suggesting risk. Other metrics also suggest risk. Therefore, different species of terrestrial and aquatic birds from the same area acquire and deposit POPs in different proportions and quantities in their eggs. Trophic levels and habitat explain the overall patterns, but detailed differences were found, some of which we are unable to explain. Based on POPs residues in terrestrial, wetland, and aquatic bird eggs, different POPs classes behave differently in a shared large inland industrial area, complicating deductions about POPs and associated risks based on one or few species.

Regions of genetic divergence in depth-separated Sebastes rockfish species pairs: Depth as a potential driver of speciation.

Depth separation is a proposed driver of speciation in marine fishes, with marine rockfish (genus Sebastes) providing a potentially informative study system. Sebastes rockfishes are commercially and ecologically important. This genus encompasses more than one hundred species and the ecological and morphological variance between these species provides opportunity for identifying speciation-driving adaptations, particularly along a depth gradient. A reduced-representation sequencing method (ddRADseq) was used to compare 95 individuals encompassing six Sebastes species. In this study, we sought to identify regions of divergence between species that were indicative of divergent adaptation and reproductive barriers leading to speciation. A pairwise comparison of S. chrysomelas (black-and-yellow rockfish) and S. carnatus (gopher rockfish) FST values revealed three major regions of elevated genomic divergence, two of which were also present in the S. miniatus (vermilion rockfish) and S. crocotulus (sunset rockfish) comparison. These corresponded with regions of both elevated DXY values and reduced nucleotide diversity in two cases, suggesting a speciation-with-gene-flow evolutionary model followed by post-speciation selective sweeps within each species. Limited whole-genome resequencing was also performed to identify mutations with predicted effects between S. chrysomelas and S. carnatus. Within these islands, we identified important SNPs in genes involved in immune function and vision. This supports their potential role in speciation, as these are adaptive vectors noted in other organisms. Additionally, changes to genes involved in pigment expression and mate recognition shed light on how S. chrysomelas and S. carnatus may have become reproductively isolated.

Identifying predictors of ventral hernia recurrence: systematic review and meta-analysis.

BACKGROUND: Ventra hernias are increasing in prevalence and many recur despite attempted repair. To date, much of the literature is underpowered and divergent. As a result there is limited high quality evidence to inform surgeons succinctly which perioperative variables influence postoperative recurrence. This systematic review aimed to identify predictors of ventral hernia recurrence. METHODS: PubMed was searched for studies reporting prognostic data of ventral hernia recurrence between 1 January 1995 and 1 January 2018. Extracted data described hernia type (primary/incisional), definitions of recurrence, methods used to detect recurrence, duration of follow-up, and co-morbidity. Data were extracted for all potential predictors, estimates and thresholds described. Random-effects meta-analysis was used. Bias was assessed with a modified PROBAST (Prediction model Risk Of Bias ASsessment Tool). RESULTS: Screening of 18 214 abstracts yielded 274 individual studies for inclusion. Hernia recurrence was defined in 66 studies (24.1 per cent), using 41 different unstandardized definitions. Three patient variables (female sex, age 65 years or less, and BMI greater than 25, 30, 35 or 40 kg/m2), five patient co-morbidities (smoking, diabetes, chronic obstructive pulmonary disease, ASA grade III-IV, steroid use), two hernia-related variables (incisional/primary, recurrent/primary), six intraoperative variables (biological mesh, bridged repair, open versus laparoscopic surgery, suture versus mesh repair, onlay/retrorectus, intraperitoneal/retrorectus), and six postoperative variables (any complication, surgical-site occurrence, wound infection, seroma, haematoma, wound dehiscence) were identified as significant prognostic factors for hernia recurrence. CONCLUSION: This study summarized the current evidence base for predicting ventral hernia recurrence. Results should inform best practice and future research.

Association between intravenous ketamine-induced stress hormone levels and long-term fear memory renewal in Sprague-Dawley rats.

Ketamine is a multimodal dissociative anesthetic and analgesic that is widely used after traumatic injury. We previously reported that an analgesic dose of intravenous (IV) ketamine infusion (10 mg/kg, 2-h) after fear conditioning enhanced short-term fear memory in rats. Here, we investigated the effects of the same dose of an IV ketamine infusion on plasma stress hormone levels and long-term fear memory in rats. Adult male Sprague-Dawley rats (9-week-old with an average weight of 308 g upon arrival) received a ketamine infusion (0 or 10 mg/kg, 2-h) immediately after auditory fear conditioning (three auditory tone and footshock [0.6 mA, 1-s] pairings) on Day 0. After the infusion, a blood sample was collected from a jugular vein catheter for corticosterone and progesterone assays, and each animal was tested on tail flick to measure thermal antinociception. One week later, animals were tested on fear extinction acquisition (Day 7), fear extinction retrieval (Day 8), and fear renewal (Day 9). The IV ketamine infusion, compared to the saline infusion, reduced locomotor activity (sedation), increased tail flick latency (antinociception), and elevated plasma corticosterone and progesterone levels. The ketamine infusion did not alter long-term fear memory extinction or fear renewal. However, elevated corticosterone and progesterone levels resulting from the ketamine infusion were correlated with sedation, antinociception, and long-term fear memory renewal. These results suggest that individual differences in sensitivity to acute ketamine may predict vulnerability to develop fear-related disorders.

Predictors for a dementia gene mutation based on gene-panel next-generation sequencing of a large dementia referral series.

Next-generation genetic sequencing (NGS) technologies facilitate the screening of multiple genes linked to neurodegenerative dementia, but there are few reports about their use in clinical practice. Which patients would most profit from testing, and information on the likelihood of discovery of a causal variant in a clinical syndrome, are conspicuously absent from the literature, mostly for a lack of large-scale studies. We applied a validated NGS dementia panel to 3241 patients with dementia and healthy aged controls; 13,152 variants were classified by likelihood of pathogenicity. We identified 354 deleterious variants (DV, 12.6% of patients); 39 were novel DVs. Age at clinical onset, clinical syndrome and family history each strongly predict the likelihood of finding a DV, but healthcare setting and gender did not. DVs were frequently found in genes not usually associated with the clinical syndrome. Patients recruited from primary referral centres were compared with those seen at higher-level research centres and a national clinical neurogenetic laboratory; rates of discovery were comparable, making selection bias unlikely and the results generalisable to clinical practice. We estimated penetrance of DVs using large-scale online genomic population databases and found 71 with evidence of reduced penetrance. Two DVs in the same patient were found more frequently than expected. These data should provide a basis for more informed counselling and clinical decision making.

Defining enhanced recovery after resection of peri-hilar cholangiocarcinoma.

INTRODUCTION: Enhanced recovery after surgery (ERAS) for peri-hilar cholangiocarcinoma (pCCA) has not been described in the literature. This study examined patients undergoing pCCA resection within a standard post hepatectomy ERAS pathway to define achievable targets suitable for these patients. METHODS: Patients undergoing pCCA resection at University Hospital Aintree (January 2009-October 2017) were identified. Achievement of key ERAS outcomes was assessed. Patients were stratified on incidence of major complications and pre-operative cardiopulmonary exercise testing. Chi Square and Mann Whitney analyses were undertaken as appropriate. Achievable ERAS targets were derived from patients who did not develop a major complication. RESULTS: 46 patients underwent resection with enhanced recovery. Median age 65 (24 male: 22 female). Key ERAS outcomes in patients who did not experience major complications are described as medians (interquartile range): length of stay 8 days (6-13), duration critical care 2 days (2-4), inotropes 6 h (0-24), epidural 3 days (3-4), early mobilization day 1 (1-2), full mobilization day 3 (3-4), urinary catheter removal day 4 (3-5), NGT removal day 1 (1-2) and restoration oral nutrition day 2 (2-4). Patients deemed high risk pre-operatively or those who developed major complications post-operatively required significantly longer critical care (p = 0.008 and p = 0.002 respectively). Other ERAS targets remained achievable in similar timeframes. CONCLUSIONS: ERAS for pCCA is achievable. Applicable ERAS standards are defined which take into account minor complications. High risk patients and those with major complications can be appropriately managed in an ERAS pathway, though there is increased need for critical care support.

Isomeric Carborane Neuromuscular Blocking Agents.

We synthesized a family of neuromuscular blocking agents (NMB) based on decamethonium, but containing a carborane cluster in the methylene chain between the two quaternary ammonium groups. The carborane cluster isomers o-NMB, m-NMB, and p-NMB were tested in animals for neuromuscular block and compared with agents used clinically: rocuronium and decamethonium. All three isomers caused reversible muscle weakness in mice as determined by grip strength and inverted screen tests, with a potency rank of p-NMB > rocuronium > decamethonium > m-NMB > o-NMB. The mechanism of action of the compounds was determined by using the in vitro rat phrenic nerve hemi-diaphragm preparation and electrophysiologic measurements in cells. Neostigmine reversed hemi-diaphragm weakness caused by the three isomers and rocuronium, but not succinylcholine. In electrophysiologic recordings of currents through acetylcholine receptor channels, the carborane compounds did not activate channel activity but did inhibit channel activation by acetylcholine. These results demonstrate that the carborane neuromuscular blocking agents are non-depolarizers in contrast to the depolarizing action of the parent compound.

IL-15 improves skeletal muscle oxidative metabolism and glucose uptake in association with increased respiratory chain supercomplex formation and AMPK pathway activation.

BACKGROUND: IL-15 is believed to play a role in the beneficial impact of exercise on muscle energy metabolism. However, previous studies have generally used supraphysiological levels of IL-15 that do not represent contraction-induced IL-15 secretion. METHODS: L6 myotubes were treated acutely (3 h) and chronically (48 h) with concentrations of IL-15 mimicking circulating (1-10 pg/ml) and muscle interstitial (100 pg/ml -20 ng/ml) IL-15 levels with the aim to better understand its autocrine/paracrine role on muscle glucose uptake and mitochondrial function. RESULTS: Acute exposure to IL-15 levels representing muscle interstitial IL-15 increased basal glucose uptake without affecting insulin sensitivity. This was accompanied by increased mitochondrial oxidative functions in association with increased AMPK pathway and formation of complex III-containing supercomplexes. Conversely, chronic IL-15 exposure resulted in a biphasic effect on mitochondrial oxidative functions and ETC supercomplex formation was increased with low IL-15 levels but decreased with higher IL-15 concentrations. The AMPK pathway was activated only by high levels of chronic IL-15 treatment. Similar results were obtained in skeletal muscle from muscle-specific IL-15 overexpressing mice that show very high circulating IL-15 levels. CONCLUSIONS: Acute IL-15 treatment that mimics local IL-15 concentrations enhances muscle glucose uptake and mitochondrial oxidative functions. That mitochondria respond differently to different levels of IL-15 during chronic treatments indicates that IL-15 might activate two different pathways in muscle depending on IL-15 concentrations. GENERAL SIGNIFICANCE: Our results suggest that IL-15 may act in an autocrine/paracrine fashion and be, at least in part, involved in the positive effect of exercise on muscle energy metabolism.

Differential plasticity of extensor and flexor motor cortex representations following visuomotor adaptation.

Representations within the primary motor cortex (M1) are capable of rapid functional changes following motor learning, known as use-dependent plasticity. GABAergic inhibition plays a role in use-dependent plasticity. Evidence suggests a different capacity for plasticity of distal and proximal upper limb muscle representations. However, it is unclear whether the motor cortical representations of forearm flexor and extensor muscles also have different capacities for plasticity. The current study used transcranial magnetic stimulation to investigate motor cortex excitability and inhibition of forearm flexor and extensor representations before and after performance of a visuomotor adaptation task that primarily targeted flexors and extensors separately. There was a decrease in extensor and flexor motor-evoked potential (MEP) amplitude after performing the extensor adaptation, but no change in flexor and extensor MEP amplitude after performing the flexor adaptation. There was also a decrease in motor cortical inhibition in the extensor following extensor adaptation, but no change in motor cortical inhibition in the flexor muscle following flexor adaptation or either of the non-prime mover muscles. Findings suggest that the forearm extensor motor cortical representation exhibits plastic change following adaptive motor learning, and broadly support the distinct neural control of forearm flexor and extensor muscles.

Alterations in the metabolic and cardiorespiratory response to exercise in Huntington's Disease.

BACKGROUND: Limited data suggests that an altered metabolic and cardiorespiratory exercise response may affect exercise performance in individuals with Huntington's disease (HD). There is no clear exploration of the response in individuals at different stages of the disease or in relation to genetic markers. This study aimed to examine the exercise response and recovery of HD participants, and the relationship to genetic and clinical markers. METHOD: HD gene-positive participants (n = 31; 9 pre-manifest; 22 manifest HD) and a healthy control group (n = 29) performed an incremental exercise test until exhaustion. Performance, cardiorespiratory, metabolic and perceptual responses to exercise were determined from a maximal cycle ergometer test throughout the exercise test and during a recovery period. RESULTS: During sub-maximal exercise, metabolic (lactate levels, oxygen uptake) and cardiorespiratory markers (heart rate) were elevated in HD participants compared to controls. Lactate elevation was specific to pre-manifest HD participants. Work capacity was reduced in both pre-manifest and manifest HD participants with tests terminated with no difference in metabolic, perceptual or cardiorespiratory markers. Submaximal oxygen uptake was correlated with motor score, whilst peak measures were unrelated to genetic or clinical markers. Heart rate recovery was attenuated in pre-manifest and manifest HD participants. CONCLUSIONS: Our findings confirm metabolic and cardiorespiratory deficits reduce exercise performance and affect recovery from an early stage in HD, with submaximal deficits related to phenotypic expression. Exercise capacity appears to be limited by an altered movement economy, thus clinicians should consider an altered exercise response and recovery may affect prescription in HD.

Combined effect of aerobic interval training and selenium nanoparticles on expression of IL-15 and IL-10/TNF-α ratio in skeletal muscle of 4T1 breast cancer mice with cachexia.

Cancer cachexia is characterized by inflammation, loss of skeletal muscle and adipose tissue mass, and functional impairment. Oxidative stress and inflammation are believed to regulate pathways controlling skeletal muscle wasting. The aim of this study was to determine the effects of aerobic interval training and the purported antioxidant treatment, selenium nanoparticle supplementation, on expression of IL-15 and inflammatory cytokines in 4T1 breast cancer-bearing mice with cachexia. Selenium nanoparticle supplementation accelerated cachexia symptoms in tumor-bearing mice, while exercise training prevented muscle wasting in tumor-bearing mice. Also, aerobic interval training enhanced the anti-inflammatory indices IL-10/TNF-α ratio and IL-15 expression in skeletal muscle in tumor-bearing mice. However, combining exercise training and antioxidant supplementation prevented cachexia and muscle wasting and additionally decreased tumor volume in 4T1 breast cancer mice. These finding suggested that combining exercise training and antioxidant supplementation could be a strategy for managing tumor volume and preventing cachexia in breast cancer.

The societal cost of Huntington's disease: are we underestimating the burden?

BACKGROUND AND PURPOSE: Approximately 9000 people in the UK are affected by Huntington's disease (HD). People with HD require ongoing health and social care support. There is a knowledge gap about costs of health and social care use associated with HD in the UK. This paper estimates the economic cost in the UK. METHODS: Data on UK patients for the year 2013 were extracted from the European Huntington's Disease Network REGISTRY study, a full clinical dataset, including the full medical history and medication history for patients with HD. National unit costs for the price year 2013 were applied to health and social care services. RESULTS: Data were available for 131 people. The mean annual cost per person with HD was £21 605. The largest proportion of this cost (65%) was due to informal care (£14 085). CONCLUSIONS: Informal care was the largest driver of costs across all stages of HD; thus there is a need to also consider the needs of carers when planning services for people with HD.

Effect of resistance exercise training on expression of Hsp70 and inflammatory cytokines in skeletal muscle and adipose tissue of STZ-induced diabetic rats.

Impairment of adipose tissue and skeletal muscles accrued following type 1 diabetes is associated with protein misfolding and loss of adipose mass and skeletal muscle atrophy. Resistance training can maintain muscle mass by changing both inflammatory cytokines and stress factors in adipose tissue and skeletal muscle. The purpose of this study was to determine the effects of a 5-week ladder climbing resistance training program on the expression of Hsp70 and inflammatory cytokines in adipose tissue and fast-twitch flexor hallucis longus (FHL) and slow-twitch soleus muscles in healthy and streptozotocin-induced diabetic rats. Induction of diabetes reduced body mass, while resistance training preserved FHL muscle weight in diabetic rats without any changes in body mass. Diabetes increased Hsp70 protein content in skeletal muscles, adipose tissue, and serum. Hsp70 protein levels were decreased in normal and diabetic rats by resistance training in the FHL, but not soleus muscle. Furthermore, resistance training decreased inflammatory cytokines in FHL skeletal muscle. On the other hand, Hsp70 and inflammatory cytokine protein levels were increased by training in adipose tissue. Also, significant positive correlations between inflammatory cytokines in adipose tissue and skeletal muscles with Hsp70 protein levels were observed. In conclusion, we found that in diabetic rats, resistance training decreased inflammatory cytokines and Hsp70 protein levels in fast skeletal muscle, increased adipose tissue inflammatory cytokines and Hsp70, and preserved FHL muscle mass. These results suggest that resistance training can maintain skeletal muscle mass in diabetes by changing inflammatory cytokines and stress factors such as Hsp70 in skeletal muscle and adipose tissue.