Antimicrobial-resistant Salmonella is detected more frequently in feed milling equipment than in raw feed components or processed animal feed.

Food for human and animal consumption can provide a vehicle for the transfer of pathogenic and antimicrobial-resistant bacteria into the food chain. We investigated the antimicrobial susceptibility of 453 Salmonella isolates collected from raw feed components, equipment and finished feed from 17 commercial feed mills in Australia between 2012 and 2021. Previous studies have found Salmonella prevalence and the diversity of Salmonella serotypes are greatest in the raw feed components. We, therefore, hypothesised that we would find a greater proportion of antimicrobial-resistant Salmonella isolates in the raw feed components compared to other sample types. We found that of 453 isolates tested, 356 (0.80) were susceptible to all antimicrobials tested, 49 (0.11) were nonsusceptible to streptomycin only and 48 (0.11) were resistant to two or more antimicrobials. Of the 48 antimicrobial-resistant isolates, 44 were found in feed milling equipment, two in raw feed components and two in finished feed. Statistical analysis, using a logistic regression with random effects model, found that the population-adjusted mean probability of detecting antimicrobial-resistant Salmonella isolates from feed milling equipment of 0.39, was larger than the probability of detecting resistant isolates in raw feed components 0.01, (P < 0.001) and in finished feed, 0.11, (P = 0.006). This propensity for antimicrobial-resistant bacteria to colonise feed milling equipment has not been previously reported. Further studies are required to understand the ecology of antimicrobial-resistant Salmonella in the feed milling environment.

Analysis of EEG Data Using Complex Geometric Structurization.

Electroencephalogram (EEG) is a common tool used to understand brain activities. The data are typically obtained by placing electrodes at the surface of the scalp and recording the oscillations of currents passing through the electrodes. These oscillations can sometimes lead to various interpretations, depending on, for example, the subject's health condition, the experiment carried out, the sensitivity of the tools used, or human manipulations. The data obtained over time can be considered a time series. There is evidence in the literature that epilepsy EEG data may be chaotic. Either way, the Embedding Theory in dynamical systems suggests that time series from a complex system could be used to reconstruct its phase space under proper conditions. In this letter, we propose an analysis of epilepsy EEG time series data based on a novel approach dubbed complex geometric structurization. Complex geometric structurization stems from the construction of strange attractors using Embedding Theory from dynamical systems. The complex geometric structures are themselves obtained using a geometry tool, the α-shapes from shape analysis. Initial analyses show a proof of concept in that these complex structures capture the expected changes brain in lobes under consideration. Further, a deeper analysis suggests that these complex structures can be used as biomarkers for seizure changes.

Is the type of neuraxial anesthesia associated with adverse neonatal outcomes among patients with preeclampsia?

OBJECTIVE: Both preeclampsia and neuraxial anesthesia can alter placental perfusion, potentially affecting the neonatal status. The objective of our study is to quantify the association between type of neuraxial anesthetic and short-term neonatal morbidity among preeclamptic patients undergoing cesarean delivery. METHODS: We performed a secondary analysis of a prospective observational cohort study. Women with singleton gestations and a diagnosis of preeclampsia who underwent cesarean delivery with neuraxial anesthesia were included in the analysis. Short-term neonatal morbidities, defined as neonatal intensive care unit (NICU) admission, arterial cord gas pH ≤7.2 and 5-minute Apgar <7, were compared based on type of neuraxial anesthetic. RESULTS: A total of 4100 patients were included in the analysis, 1696 (41.4%) received spinal anesthesia 1848 (45.1%) received epidural anesthesia and 556 (13.5%) received a combined spinal-epidural (CSE). Antepartum and intrapartum characteristics significantly differed between the groups (p≤0.02). After adjusted analysis, spinal anesthesia was associated with reduced odds of NICU admission, compared with epidural or CSE (OR; 95% CI: 0.79; 0.63-0.98, 0.71; 0.53-0.94, respectively). Spinal anesthesia was also associated with lower odds of a 5-minute Apgar <7 compared with epidural anesthesia (OR 0.59; 95% CI; 0.43-0.83). We found no association between type of anesthesia and arterial cord pH ≤7.2. In stratiifed analysis by gestational age, no association between the type of neuraxial anesthesia and neonatal outcomes was noted among term infants, but associations persisted in preterm infants. CONCLUSIONS: Among women with preeclampsia undergoing cesarean delivery, spinal anesthesia may be associated with reduced short-term neonatal morbidity in preterm infants, compared with epidural or CSE.

Salmonella monitoring programs in Australian feed mills: a retrospective analysis.

The availability of safe, commercially prepared stock feed for production animals is an important step in ensuring animal health and welfare and the safety of food animal products for human consumption. Animal feed quality assurance programs include microbiological monitoring of raw materials, mill equipment and finished feed. Over a period of 16 years, 23,963 samples for Salmonella culture and serotyping were collected from 22 stock feed mills. A multivariable generalized linear mixed model (GLMM) was used to identify mill and sample type factors that increase the odds of detecting Salmonella. The odds of detecting a Salmonella positive sample was greatest in samples from raw materials and in mills that processed restricted animal material (RAM). The percentage of positive samples ranged from 7.2% in 2003 to 2.8% in 2017. Of the 1,069 positive samples, 976 were serotyped with 61 different Salmonella serotypes isolated. The serotype most frequently isolated from raw materials was S. Agona, (n = 108) whilst S. Anatum was the serotype most frequently isolated from equipment and finished feed (n = 156). The diversity of Salmonella serotypes differed between mills and different stages of the production line. Microbiological monitoring in the commercial preparation of animal feed in Australian stock feed mills guides the implementation of quality control measures and risk mitigation strategies thereby reducing the prevalence and diversity of potentially zoonotic bacteria such as Salmonella, enhancing food safety for both animal and consumer.

Effects of pro-inflammatory cytokines on cannabinoid CB1 and CB2 receptors in immune cells.

AIMS: To investigate the regulation of cannabinoid receptors CB1 and CB2 on immune cells by pro-inflammatory cytokines and its potential relevance to the inflammatory neurological disease, multiple sclerosis (MS). CB1 and CB2 signalling may be anti-inflammatory and neuroprotective in neuroinflammatory diseases. Cannabinoids can suppress inflammatory cytokines but the effects of these cytokines on CB1 and CB2 expression and function are unknown. METHODS: Immune cells from peripheral blood were obtained from healthy volunteers and patients with MS. Expression of CB1 and CB2 mRNA in whole blood cells, peripheral blood mononuclear cells (PBMC) and T cells was determined by quantitative real-time polymerase chain reaction (qRT-PCR). Expression of CB1 and CB2 protein was determined by flow cytometry. CB1 and CB2 signalling in PBMC was determined by Western blotting for Erk1/2. RESULTS: Pro-inflammatory cytokines IL-1ß, IL-6 and TNF-α (the latter likely NF-κB dependently) can upregulate CB1 and CB2 on human whole blood and peripheral blood mononuclear cells (PBMC). We also demonstrate upregulation of CB1 and CB2 and increased IL-1ß, IL-6 and TNF-α mRNA in blood of patients with MS compared with controls. CONCLUSION: The levels of CB1 and CB2 can be upregulated by inflammatory cytokines, which can explain their increase in inflammatory conditions including MS.

Central inflammation versus peripheral regulation in multiple sclerosis.

Th17 cells are a highly pro-inflammatory T-helper cell subset characterised by the expression of IL17. They have been implicated in a variety of allergic and autoimmune conditions. T-regulatory (Treg) cells, a subset of CD4 cells which express Foxp3, CD25, IL10 and TGFß, can suppress the activity of Th17 cells. In this study, we show that the circulating levels of Th17 and Treg cells in peripheral blood are correlated; furthermore, the expression of the pro-inflammatory cytokine IL17 and the anti-inflammatory cytokine IL10 by CD4 cells are also correlated. However, we found no clear correlation between cerebrospinal fluid (CSF) IL10 and IL17 cytokine levels in MS, approaching a negative correlation at the time of relapse, and an overall negative correlation between CSF IL17 and TGFß levels, suggesting a lack of central regulation of pro:anti-inflammatory balance in this demyelinating condition.

Th17/Th1 phenotype in demyelinating disease.

BACKGROUND: Th17 cells are thought to contribute to the immunopathology of allergic and autoimmune conditions. Their role in multiple sclerosis (MS) pathology remains to be fully elucidated. OBJECTIVE: To assess peripheral blood Th17 responses in patients with MS compared to controls. METHODS: We isolated peripheral blood mononuclear cells from 41 MS patients and 23 healthy controls, which were then stimulated using phorbol ester and ionomycin, labelled for CD3, CD8, CD154, IL-17 and IFN-gamma and analysed using flow cytometry. RESULTS: Minimal IL-17 was detectable in unstimulated cells. Following stimulation with phorbol ester and ionomycin, PBMCs taken from MS patients in relapse developed a more inflammatory profile than those taken from controls or non-relapse patients, with greater expression of CD154, IL-17 and dual expression of IL-17/IFN-gamma. CONCLUSION: We suggest a greater tendency to Th17 and Th1/Th17 response to non-specific stimulation in MS patients in relapse compared to controls and non-relapse patients.

Multiple sclerosis findings in the spinal cord.

The spinal cord is commonly affected by acute demyelinating lesions, chronic tissue loss and atrophy in multiple sclerosis, and is a clinically eloquent site. Historically, however, more attention has been focussed on the analysis and contribution of brain lesions. In this review, we discuss some of the key findings from MRI analysis and histopathological examination of the spinal cord, and how they relate to the clinical characteristics of this common and disabling disease.

Regulation of leptin synthesis and secretion before birth: implications for the early programming of adult obesity.

A series of epidemiological, clinical and experimental studies have shown that there are associations between the fetal and neonatal nutritional environment and the amount and distribution of adipose tissue in adult life. This review considers the evidence for these relationships and discusses the potential impact of the prenatal nutritional experience on the development of the endocrine and neuroendocrine systems that regulate energy balance, with a particular emphasis on the role of the adipocyte-derived hormone, leptin. In the rodent, leptin derived from the mother may exert an important influence on the development of the appetite regulatory neural network and on the subsequent regulation of leptin synthesis and the risk for obesity in the offspring. In species such as the human and sheep, there is also recent evidence that the synthesis and secretion of adipocyte-derived hormones, such as leptin, are regulated in fetal life. Furthermore, the hypothalamic neuropeptides that regulate energy intake and expenditure in adult life are also present within the fetal brain and may be regulated by the prevailing level of maternal and hence fetal nutrient and hormonal signals, including leptin. This work is important in determining those initiating mechanisms within the 'fat-brain' axis in early life that precede the development of adult obesity.

Impact of periconceptional nutrition on maternal and fetal leptin and fetal adiposity in singleton and twin pregnancies.

It has been proposed that maternal nutrient restriction may alter the functional development of the adipocyte and the synthesis and secretion of the adipocyte-derived hormone, leptin, before birth. We have investigated the effects of restricted periconceptional undernutrition and/or restricted gestational nutrition on fetal plasma leptin concentrations and fetal adiposity in late gestation. There was no effect of either restricted periconceptional or gestational nutrition on maternal or fetal plasma leptin concentrations in singleton or twin pregnancies during late gestation. In ewes carrying twins, but not singletons, maternal plasma leptin concentrations in late gestation were directly related to the change in ewe weight that occurred during the 60 days before mating [maternal leptin = 0.9 (change in ewe weight) + 7.8; r = 0.6, P < 0.05]. In twin, but not singleton, pregnancies, there was also a significant relationship between maternal and fetal leptin concentrations (maternal leptin = 0.5 fetal leptin + 4.2, r = 0.63, P < 0.005). The relative mass of perirenal fat was also significantly increased in twin fetal sheep in the control-restricted group (6.0 +/- 0.5) compared with the other nutritional groups (control-control: 4.1 +/- 0.4; restricted-restricted: 4.4 +/- 0.4; restricted-control: 4.3 +/- 0.3). In conclusion, the impact of maternal undernutrition on maternal plasma leptin concentrations during late gestation is dependent on fetal number. Furthermore, we have found that there is an increased fetal adiposity in the twins of ewes that experienced restricted nutrition throughout gestation, and this may be important in the programming of postnatal adiposity.

Effects of recombinant human follicle-stimulating hormone on embryo development in mice.

We have developed a protocol using recombinant human follicle-stimulating hormone (rhFSH) to induce ovarian stimulation in the mouse to investigate its impact on preimplantation embryo development. Embryos were collected from adult female C57Bl/6 x CBA F1 mice treated with rhFSH (0, 2.5, 5.0, 10.0, or 20.0 IU) or 5 IU equine chorionic gonadotropin (eCG). Embryos were also recovered from nontreated control mice. Embryos were cultured in vitro for 88 h, and the stage of development was morphologically assessed. The allocation of cells to the inner cell mass or trophectoderm of blastocysts was determined by differential nuclear staining. The expression of insulin-like growth factor 2 (IGF-II), the insulin-like growth factor receptor (IGF-II receptor), and vascular endothelial growth factor (VEGF) in blastocysts was measured by real-time RT-PCR. Blastocyst development was reduced in the 10 (72.3 +/- 5.1%) and 20 (77.3 +/- 5.6%) IU rhFSH groups compared with control embryos (96.7 +/- 1.0%). The number of inner cell mass cells was reduced (P < 0.001) in the 5, 10, and 20 IU rhFSH groups and the eCG group compared with control embryos. We did not find any effect of rhFSH treatment on IGF-II, IGF-II receptor, or VEGF expression in blastocysts compared with the control group. eCG treatment, however, significantly increased the expression of IGF-II in blastocysts. These results indicate that ovarian stimulation with rhFSH impairs the in vitro development of preimplantation mouse embryos, and these results may have potential implications for clinical ovarian stimulation during infertility treatment and subsequent embryo quality.

A prospective study of conditions associated with multiple sclerosis in a cohort of 658 consecutive outpatients attending a multiple sclerosis clinic.

The cause of multiple sclerosis (MS) remains unknown. It is largely regarded as being an inflammatory autoimmune disease and has been reported in association with other inflammatory/autoimmune diseases. We performed a prospective study in 658 consecutive patients diagnosed with MS attending our outpatient MS management clinic between June 2002 and June 2003. Prevalence of associated conditions in these patients was calculated and compared with values from population studies using chi-square tests, odds ratios and confidence intervals. The MS population had significantly increased rates of asthma, inflammatory bowel disease, type 1 diabetes mellitus, pernicious anaemia, autoimmune thyroid disease, uveitis, seronegative spondyloarthropathies, bipolar disorder and melanoma compared to the general population. Both T helper type 1 (Th1)-mediated and T helper type 2 (Th2)-mediated diseases were significantly increased compared to the general population. There were also interesting associations seen with polyglandular autoimmune syndrome and rare single case associations. MS is associated with several other conditions. This work does not give evidence for the hypothesis that MS and atopy, reflecting Th1 and Th2 polarization, respectively, are mutually exclusive. Further work, ideally with a matched control population, is indicated.

Nutritional manipulation of fetal adipose tissue deposition and uncoupling protein 1 messenger RNA abundance in the sheep: differential effects of timing and duration.

A range of epidemiological and experimental studies have indicated that suboptimal nutrition at different stages of gestation is associated with an increased prevalence of adult hypertension, cardiovascular disease, and obesity. The timing of prenatal nutrient restriction is important in determining postnatal outcomes-including obesity. The present study, aimed to determine the extent to which fetal adiposity and expression of the key thermogenic protein, uncoupling protein (UCP)1, are altered by restriction of maternal nutrient intake imposed during four different periods, starting from before conception. Maternal nutrient intake was restricted from 60 days before until 8 days after mating (periconceptional nutrient restriction; R-C), from 60 days before mating and throughout gestation (R-R), from 8 days gestation until term (C-R), or from 115 days gestation until term. Fetal perirenal adipose tissue (PAT) was sampled near to term at approximately 143 days. UCP1 mRNA, but not protein, abundance in PAT was increased in fetuses in the R-R group (C-C 63 +/- 18; R-C 83 +/- 43; C-R 103 +/- 38; R-R 167 +/- 50 arbitrary units (P < 0.05)). In contrast, the abundance of UCP1 mRNA, but not protein, in fetal PAT was decreased when maternal nutrition was restricted from 115 days gestation. The major effect of maternal nutrient restriction on adipose tissue deposition occurred in the C-R group, in which the proportion of fetal fat was doubled, whereas maternal nutrient restriction from 115 days gestation reduced fetal fat deposition. In conclusion, there are differential effects of maternal and therefore fetal nutrient restriction on UCP1 mRNA expression and fetal fat mass and these effects are dependent on the timing and duration of nutrient restriction.

Early embryonic environment, the fetal pituitary-adrenal axis and the timing of parturition.

It is well established in the sheep, that the normal timing of parturition is dependent on a prepartum activation of the fetal pituitary-adrenal axis. We have recently demonstrated for the first time that embryo number, embryo sex, and alterations in the environment of the early embryo, including exposure to maternal undernutrition during the periconceptional period, alter the timing and level of activation of the pituitary-adrenal axis in the sheep fetus during late gestation. There is a delay in activation of the fetal HPA axis in twin fetuses and we speculate that the diminished adrenocortical responsiveness in the twin fetus may be an adaptive response, which counters the impact of the potential enhanced intrauterine stress experienced by a twin fetus, thereby reducing the possibility of preterm delivery. We have also reported that a moderate restriction of maternal nutrition to during the periconceptional period (from 60 days before and for one week after conception) resulted in an earlier activation of the pituitary-adrenal axis of twin, but not singleton, fetuses during late gestation. A series of studies using assisted reproductive technologies have also found that perturbation of the early embryonic environment results in a dysregulation of placental and fetal growth and development and in the timing of normal parturition. In summary, after several decades of work focussed on events in late gestation associated with the prepartum activation and stress responsiveness of the fetal HPA axis, our recent studies indicate that the environment of the early embryo may have a significant role to play in determining the timing and level of the prepartum activation of this axis and potentially on the functional capacity of the axis to respond to acute or chronic stress in later life.

Maternal undernutrition throughout pregnancy increases adrenocorticotrophin receptor and steroidogenic acute regulatory protein gene expression in the adrenal gland of twin fetal sheep during late gestation.

We have previously demonstrated that maternal undernutrition during either the 'periconceptional' (i.e. from 60 days (d) before until 7 d after mating) or 'gestational' periods (i.e. from 8 d after mating until the end of pregnancy) have differential effects on the subsequent development of the hypothalamo-pituitary-adrenocortical (HPA) axis and on adrenal growth and steroidogenesis in the sheep fetus during late gestation (term=147+/-3 d gestation). The specific mechanisms by which periconceptional or gestational undernutrition result in activation of the fetal HPA axis in late gestation are unclear. We have therefore investigated the impact of maternal nutrient restriction imposed either during the periconceptional period, or between 8 and 147 d gestation on the expression of specific genes in the fetal pituitary and adrenal which regulate adrenal steroidogenesis in late gestation. Ewes were maintained on either a Control (C) or Restricted (R, 70% of C) diet from 60 d before until 7 d after mating (periconceptional period) and then maintained on either a Control or Restricted diet from 8 d after mating for the remainder of pregnancy (gestational period). Four nutritional treatment groups were therefore generated (C-C, C-R, R-R and R-C). Whilst periconceptional undernutrition (R-R and R-C groups) resulted in higher fetal plasma adrenocorticotrophic hormone (ACTH) at 135-146 d gestation, there was no change in the relative level of expression of the ACTH receptor (MC2R), steroidogenic acute regulatory protein (StAR) or steroidogenic enzyme mRNAs in the fetal adrenal in late gestation. Exposure to gestational undernutrition (R-R and C-R groups), however, resulted in a stimulation in the relative level of expression of MC2R mRNA (P=0.001) and StAR mRNA (P=0.007) in the fetal adrenal during late gestation. This study provides new insights into the potential mechanisms by which alterations of the nutrient environment of the fetus at different stages of gestation may result in differential activation of the fetal HPA axis.

Periconceptional nutrition programs development of the cardiovascular system in the fetal sheep.

It has been proposed that fetal adaptations to intrauterine nutrient deprivation permanently reprogram the cardiovascular system. We investigated the impact of restricted periconceptional nutrition and/or restricted gestational nutrition on fetal arterial blood pressure (BP), heart rate, rate pressure product, and the fetal BP responses to ANG II and the angiotensin-converting enzyme inhibitor captopril during late gestation. Restricted periconceptional nutrition resulted in an increase in fetal mean arterial BP between 115 and 125 days gestation (restricted 41.5 +/- 2.8 mmHg, n = 12; control 38.5 +/- 1.5 mmHg, n = 13) and between 135 and 147 days gestation (restricted 50.5 +/- 2.2 mmHg, n = 8; control 42.5 +/- 1.9 mmHg, n = 10) as well as an increase in the rate pressure product in twin, but not singleton, fetuses between 115 and 147 days gestation. Mean BP and fetal plasma ACTH were also positively correlated in twin, but not singleton, fetuses. This is the first demonstration that maternal undernutrition during the periconceptional period results in an increase in fetal arterial BP. This increase occurs concomitantly with an increase in fetal ACTH but is not dependent on activation of the fetal renin-angiotensin system.

Circulating leptin concentrations are positively related to leptin messenger RNA expression in the adipose tissue of fetal sheep in the pregnant ewe fed at or below maintenance energy requirements during late gestation.

We have investigated the effects of maternal undernutrition during late gestation on maternal and fetal plasma concentrations of leptin and on leptin gene expression in fetal perirenal adipose tissue. Pregnant ewes were randomly assigned at 115 days of gestation (term = 147 +/- 3 days [mean +/- SEM]) to either a control group (n = 13) or an undernourished group (n = 16) that received approximately 50% of the control diet until 144-147 days of gestation. Maternal plasma glucose, but not leptin, concentrations were lower in the undernourished ewes. A significant correlation was found, however, between mean maternal plasma leptin (y) and glucose (x) concentrations (y = 2.9x - 2.4; r = 0.51, P < 0.02) when the control and undernourished groups were combined. Fetal plasma glucose and insulin, but not fetal leptin, concentrations were lower in the undernourished ewes, and no correlation was found between mean fetal leptin concentrations and either mean fetal glucose or insulin concentrations. A positive relationship, however, was found between mean fetal (y) and maternal (x) plasma leptin concentrations (y = 0.18x + 0.45; r = 0.66, P < 0.003). No significant difference was found in the relative abundance of leptin mRNA in fetal perirenal fat between the undernourished (0.60 +/- 0.09, n = 10) and control (0.70 +/- 0.08, n = 10) groups. Fetal plasma concentrations of leptin (y) and leptin mRNA levels (x) in perirenal adipose tissue were significantly correlated (y = 1.5x +/- 0.3; r = 0.69, P < 0.05). In summary, the capacity of leptin to act as a signal of moderate maternal undernutrition may be limited before birth in the sheep.

Protease inhibitors are associated with a slowed progression of HIV-related renal diseases.

AIMS: While angiotensin-con-verting enzyme inhibitors and zidovudine may improve the course of the most common HIV-related renal disease, HIV-associated nephropathy (HIVAN), the effect of anti-retroviral combination therapy on this and other HIV-related renal diseases has not been assessed. This study describes the clinical course of HIV-related renal diseases and the effect of protease inhibitors on their progression. METHODS: This retrospective cohort study reviews the clinical course of 19 patients with a clinical or biopsy-proven diagnosis of HIVAN or other HIV-related renal diseases. Groups progressing and not progressing to ESRD were compared using longitudinal analyses to assess the association between creatinine clearance and clinical and therapeutic factors. RESULTS: The cohort consisted of 16 African-Americans, 2 Caucasians and 1 Native American. Their modes of HIV infection were intravenous drug use (7), a history of men having sex with men (3) and heterosexual behavior (5). Patients were followed for a median of 16.6 months. Seven patients reached ESRD. Loss of creatinine clearance over time did not differ among genders, races, or patients with different modes of HIV infection. Longitudinal analyses demonstrated an association between protease inhibitors and prednisone and a slower decline in creatinine clearance in multivariable models (p = 0.04 and 0.003, respectively). CONCLUSIONS: The epidemiology and clinical course of HIV-related renal diseases is more heterogeneous than previously described. This study suggests a benefit to the use of protease inhibitors and prednisone on the progression of these nephropathies.