Do Human Extraintestinal Escherichia coli Infections Resistant to Expanded-Spectrum Cephalosporins Originate From Food-Producing Animals? A Systematic Review

To find out whether food-producing animals (FPAs) are a source of extraintestinal expanded-spectrum cephalosporin-resistant Escherichia coli (ESCR-EC) infections in humans, Medline, Embase, and the Cochrane Database of Systematic Reviews were systematically reviewed. Thirty-four original, peer-reviewed publications were identified for inclusion. Six molecular epidemiology studies supported the transfer of resistance via whole bacterium transmission (WBT), which was best characterized among poultry in the Netherlands. Thirteen molecular epidemiology studies supported transmission of resistance via mobile genetic elements, which demonstrated greater diversity of geography and host FPA. Seventeen molecular epidemiology studies did not support WBT and two did not support mobile genetic element-mediated transmission. Four observational epidemiology studies were consistent with zoonotic transmission. Overall, there is evidence that a proportion of human extraintestinal ESCR-EC infections originate from FPAs. Poultry, in particular, is probably a source, but the quantitative and geographical extent of the problem is unclear and requires further investigation.

Programming rumen bacterial communities in newborn Merino lambs

Establishment of the rumen microbiome can be affected by both early-life dietary measures and rumen microbial inoculation. This study used a 2 × 3 factorial design to evaluate the effects of inclusion of dietary fat type and the effects of rumen inoculum from different sources on ruminal bacterial communities present in early stages of the lambs’ life. Two different diets were fed ad libitum to 36 pregnant ewes (and their lambs) from 1 month pre-lambing until weaning. Diets consisted of chaffed lucerne and cereal hay and 4% molasses, with either 4% distilled coconut oil (CO) provided as a source of rumen-active fat or 4% Megalac® provided as a source of rumen-protected fat (PF). One of three inoculums was introduced orally to all lambs, being either (1) rumen fluid from donor ewes fed the PF diet; (2) rumen fluid from donor ewes fed CO; or (3) a control treatment of MilliQ-water. After weaning at 3 months of age, each of the six lamb treatment groups were grazed in spatially separated paddocks. Rumen bacterial populations of ewes and lambs were characterised using 454 amplicon pyrosequencing of the V3/V4 regions of the 16S rRNA gene. Species richness and biodiversity of the bacterial communities were found to be affected by the diet in ewes and lambs and by inoculation treatment of the lambs. Principal coordinate analysis and analysis of similarity (ANOSIM) showed between diet differences in bacterial community groups existed in ewes and differential bacterial clusters occurred in lambs due to both diet and neonatal inoculation. Diet and rumen inoculation acted together to clearly differentiate the bacterial communities through to weaning, however the microbiome effects of these initial early life interventions diminished with time so that rumen bacterial communities showed greater similarity 2 months after weaning. These results demonstrate that ruminal bacterial communities of newborn lambs can be altered by modifying the diet of their mothers. Moreover, the rumen microbiome of lambs can be changed by diet while they are suckling or by inoculating their rumen, and resulting changes in the rumen bacterial microbiome can persist beyond weaning.

The Occurrence and Toxicity of Indospicine to Grazing Animals

Indospicine is a non-proteinogenic amino acid which occurs in Indigofera species with widespread prevalence in grazing pastures across tropical Africa, Asia, Australia, and the Americas. It accumulates in the tissues of grazing livestock after ingestion of Indigofera. It is a competitive inhibitor of arginase and causes both liver degeneration and abortion. Indospicine hepatoxicity occurs universally across animal species but the degree varies considerably between species, with dogs being particularly sensitive. The magnitude of canine sensitivity is such that ingestion of naturally indospicine-contaminated horse and camel meat has caused secondary poisoning of dogs, raising significant industry concern. Indospicine impacts on the health and production of grazing animals per se has been less widely documented. Livestock grazing Indigofera have a chronic and cumulative exposure to this toxin, with such exposure experimentally shown to induce both hepatotoxicity and embryo-lethal effects in cattle and sheep. In extensive pasture systems, where animals are not closely monitored, the resultant toxicosis may well occur after prolonged exposure but either be undetected, or even if detected not be attributable to a particular cause. Indospicine should be considered as a possible cause of animal poor performance, particularly reduced weight gain or reproductive losses, in pastures where Indigofera are prevalent.

First detection of extended-spectrum cephalosporin- and fluoroquinolone-resistant Escherichia coli in Australian food-producing animals

This study aimed to define the frequency of resistance to critically important antimicrobials (CIAs) [i.e. extended-spectrum cephalosporins (ESCs), fluoroquinolones (FQs) and carbapenems] among Escherichia coli isolates causing clinical disease in Australian food-producing animals. Clinical E. coli isolates (n = 324) from Australian food-producing animals [cattle (n = 169), porcine (n = 114), poultry (n = 32) and sheep (n = 9)] were compiled from all veterinary diagnostic laboratories across Australia over a 1-year period. Isolates underwent antimicrobial susceptibility testing to 18 antimicrobials using the Clinical and Laboratory Standards Institute disc diffusion method. Isolates resistant to CIAs underwent minimum inhibitory concentration determination, multilocus sequence typing (MLST), phylogenetic analysis, plasmid replicon typing, plasmid identification, and virulence and antimicrobial resistance gene typing. The 324 E. coli isolates from different sources exhibited a variable frequency of resistance to tetracycline (29.0–88.6%), ampicillin (9.4–71.1%), trimethoprim/sulfamethoxazole (11.1–67.5%) and streptomycin (21.9–69.3%), whereas none were resistant to imipenem or amikacin. Resistance was detected, albeit at low frequency, to ESCs (bovine isolates, 1%; porcine isolates, 3%) and FQs (porcine isolates, 1%). Most ESC- and FQ-resistant isolates represented globally disseminated E. coli lineages (ST117, ST744, ST10 and ST1). Only a single porcine E. coli isolate (ST100) was identified as a classic porcine enterotoxigenic E. coli strain (non-zoonotic animal pathogen) that exhibited ESC resistance via acquisition of blaCMY-2. This study uniquely establishes the presence of resistance to CIAs among clinical E. coli isolates from Australian food-producing animals, largely attributed to globally disseminated FQ- and ESC-resistant E. coli lineages.

Phenotypic plasticity and longevity in plants and animals: cause and effect?

Immobile plants and immobile modular animals outlive unitary animals. This paper discusses competing but not necessarily mutually exclusive theories to explain this extreme longevity, especially from the perspective of phenotypic plasticity. Stem cell immortality, vascular autonomy, and epicormic branching are some important features of the phenotypic plasticity of plants that contribute to their longevity. Monocarpy versus polycarpy can also influence the kind of senescent processes experienced by plants. How density-dependent phenomena affecting the establishment of juveniles in these immobile organisms can influence the evolution of senescence, and consequently longevity, is reviewed and discussed. Whether climate change scenarios will favour long-lived or short-lived organisms, with their attendant levels of plasticity, is also presented.

Epithelial sodium channel in airway epithelium of the newborn infant : Implications for postnatal pulmonary adaptation

The aim of the present thesis was to study the role of the epithelial sodium channel (ENaC) in clearance of fetal lung fluid in the newborn infant by measurement of airway epithelial expression of ENaC, of nasal transepithelial potential difference (N-PD), and of lung compliance (LC). In addition, the effect of postnatal dexamethasone on airway epithelial ENaC expression was measured in preterm infants with bronchopulmonary dysplasia (BPD). The patient population was formed of selected term newborn infants born in the Department of Obstetrics (Studies II-IV) and selected preterm newborn infants treated in the neonatal intensive care unit of the Hospital for Children and Adolescents (Studies I and IV) of the Helsinki University Central Hospital in Finland. A small population of preterm infants suffering from BPD was included in Study I. Studies I, III, and IV included airway epithelial measurement of ENaC and in Studies II and III, measurement of N-PD and LC. In Study I, ENaC expression analyses were performed in the Research Institute of the Hospital for Sick Children in Toronto, Ontario, Canada. In the following studies, analyses were performed in the Scientific Laboratory of the Hospital for Children and Adolescents. N-PD and LC measurements were performed at bedside in these hospitals. In term newborn infants, the percentage of amiloride-sensitive N-PD, a surrogate for ENaC activity, measured during the first 4 postnatal hours correlates positively with LC measured 1 to 2 days postnatally. Preterm infants with BPD had, after a therapeutic dose of dexamethasone, higher airway epithelial ENaC expression than before treatment. These patients were subsequently weaned from mechanical ventilation, probably as a result of the clearance of extra fluid from the alveolar spaces. In addition, we found that in preterm infants ENaC expression increases with gestational age (GA). In preterm infants, ENaC expression in the airway epithelium was lower than in term newborn infants. During the early postnatal period in those born both preterm and term airway epithelial βENaC expression decreased significantly. Term newborn infants delivered vaginally had a significantly smaller airway epithelial expression of αENaC after the first postnatal day than did those delivered by cesarean section. The functional studies showed no difference in N-PD between infants delivered vaginally and by cesarean section. We therefore conclude that the low airway epithelial expression of ENaC in the preterm infant and the correlation of N-PD with LC in the term infant indicate a role for ENaC in the pathogenesis of perinatal pulmonary adaptation and neonatal respiratory distress. Because dexamethasone raised ENaC expression in preterm infants with BPD, and infants were subsequently weaned from ventilator therapy, we suggest that studies on the treatment of respiratory distress in the preterm infant should include the induction of ENaC activity.

Thrombin regulation in newborn infants

The coagulation system of newborn infants differs markedly from that of older children and adults. The activities of most coagulation factors and anticoagulants are low, leading to altered regulation in the formation of the key enzyme, thrombin. Timely and adequate generation of thrombin is essential, as thrombin activates platelets and many coagulation factors, cleaves fibrinogen into fibrin and activates the antithrombotic and anti-inflammatory protein C pathway. On the other hand, excess thrombin may promote thrombotic complications and exacerbate harmful inflammatory reactions. Despite the characteristic features, the newborn coagulation system can be considered physiological, since healthy newborns rarely show haemorrhagic or thrombotic complications. Sick newborns, however, often encounter clinical situations that challenge their coagulation system. The aim of this study was to clarify the behaviour of the neonatal coagulation system in selected clinical situations, with a special emphasis on the generation of thrombin. Thrombin was measured by in vivo thrombin generation markers and by thrombin generation potential in vitro. The patient groups included sick newborns undergoing intensive care and receiving fresh-frozen plasma (FFP), requiring exchange transfusions (ET) or presenting with a congenital heart defect requiring open heart surgery. Additionally, healthy newborns with inherited heterozygous factor V Leiden (FVL) mutation were studied. Thrombin generation potential was also analysed in cord plasma of healthy infants and in adults. Healthy as well as sick newborn infants showed lower total thrombin generation potential in vitro but faster initiation of thrombin generation than adults. These findings were qualitatively similar when plasma was supplemented with platelets. Platelets, however, significantly altered the effect of the major anticoagulant, activated protein C (APC), on thrombin generation potential. In accordance with previous studies, thrombin generation in healthy newborn platelet-poor plasma was resistant to the anticoagulant effects of APC, but when the plasma was supplemented with platelets APC attenuated thrombin generation significantly more in newborns than in adults. In vivo generation of thrombin was elevated in nearly all of the sick newborn infants. The low-volume FFP transfusion as opposed to the change from neonatal to adult blood in ET exerted markedly different effects on neonatal thrombin generation. FFP reduced the in vivo generation of thrombin in those newborns with the highest pretransfusional thrombin generation, thus acting as an anticoagulant agent. In those infants with lower pretransfusional thrombin generation, the effect of FFP on thrombin generation was fairly neutral. On the other hand, the combination of red blood cells and FFP, used to perform ET, significantly increased the in vivo thrombin formation and shifted the balance in the newborn coagulation system to the procoagulant direction. Cardiopulmonary bypass (CPB) also significantly increased the in vivo thrombin generation, but the thrombin generation profile during CPB differed from that previously observed in adults. Escalation of thrombin at early reperfusion was not observed in newborns; in adults, its occurrence is associated with postoperative myocardial damage. Finally, in healthy newborns with FVL heterozygosity, faster initiation of thrombin generation was observed compared with controls. Interestingly, FV level was lower in FVL-heterozygous infants, possibly to counteract the procoagulant effects induced by FVL. In conclusion, unique features regarding thrombin regulation in newborn infants were observed. These features included a novel platelet effect on the regulation of the protein C pathway. The clinical challenges mainly seemed to shift the balance in the coagulation system of newborns to the procoagulant direction. Blood component transfusions markedly affected coagulation in a manner specific to the product but that could also be altered by the clinical situation. Overall, the results highlight the need for understanding developmental haemostasis for both diagnostic and therapeutic purposes.

Detection, epidemiology and host spectrum of cowpox and Borna disease virus infections

Several orthopoxviruses (OPV) and Borna disease virus (BDV) are enveloped, zoonotic viruses with a wide geographical distribution. OPV antibodies cross-react, and former smallpox vaccination has therefore protected human populations from another OPV infection, rodent-borne cowpox virus (CPXV). Cowpox in humans and cats usually manifests as a mild, self-limiting dermatitis and constitutional symptoms, but it can be severe and even life-threatening in the immunocompromised. Classical Borna disease is a progressive meningoencephalomyelitis in horses and sheep known in central Europe for centuries. Nowadays the virus or its close relative infects humans and also several other species in central Europe and elsewhere, but the existence of human Borna disease with its suspected neuropsychiatric symptoms is controversial. The epidemiology of BDV is largely unknown, and the present situation is even more intriguing following the recent detection of several-million-year-old, endogenized BDV genes in primate and various other vertebrate genomes. The aims of this study were to elucidate the importance of CPXV and BDV in Finland and in possible host species, and particularly to 1) establish relevant methods for the detection of CPXV and other OPVs as well as BDV in Finland, 2) determine whether CPXV and BDV exist in Finland, 3) discover how common OPV immunity is in different age groups in Finland, 4) characterize possible disease cases and clarify their epidemiological context, 5) establish the hosts and possible reservoir species of these viruses and their geographical distribution in wild rodents, and 6) elucidate the infection kinetics of BDV in the bank vole. An indirect immunofluorescence assay and avidity measurement were established for the detection, timing and verification of OPV or BDV antibodies in thousands of blood samples from humans, horses, ruminants, lynxes, gallinaceous birds, dogs, cats and rodents. The mostly vaccine-derived OPV seroprevalence was found to decrease gradually according to the year of birth of the sampled human subjects from 100% to 10% in those born after 1977. On the other hand, OPV antibodies indicating natural contact with CPXV or other OPVs were commonly found in domestic and wild animals: the horse, cow, lynx, dog, cat and, with a prevalence occasionally even as high as 92%, in wild rodents, including some previously undetected species and new regions. Antibodies to BDV were detected in humans, horses, a dog, cats, and for the first time in wild rodents, such as bank voles (Myodes glareolus). Because of the controversy within the human Borna disease field, extra verification methods were established for BDV antibody findings: recombinant nucleocapsid and phosphoproteins were produced in Escherichia coli and in a baculovirus system, and peptide arrays were additionally applied. With these verification assays, Finnish human, equine, feline and rodent BDV infections were confirmed. Taken together, wide host spectra were evident for both OPV and BDV infections based on the antibody findings, and OPV infections were found to be geographically broadly distributed. PCR amplification methods were utilised for hundreds of blood and tissue samples. The methods included conventional, nested and real-time PCRs with or without the reverse transcription step and detecting four or two genes of OPVs and BDV, respectively. OPV DNA could be amplified from two human patients and three bank voles, whereas no BDV RNA was detected in naturally infected individuals. Based on the phylogenetic analyses, the Finnish OPV sequences were closely related although not identical to a Russian CPXV isolate, and clearly different from other CPXV strains. Moreover, the Finnish sequences only equalled each other, but the short amplicons obtained from German rodents were identical to monkeypox virus, in addition to German CPXV variants. This reflects the close relationship of all OPVs. In summary, RNA of the Finnish BDV variant could not be detected with the available PCR methods, but OPV DNA infrequently could. The OPV species infecting the patients of this study was proven to be CPXV, which is most probably also responsible for the rodent infections. Multiple cell lines and some newborn rodents were utilised in the isolation of CPXV and BDV from patient and wildlife samples. CPXV could be isolated from a child with severe, generalised cowpox. BDV isolation attempts from rodents were unsuccessful in this study. However, in parallel studies, a transient BDV infection of cells inoculated with equine brain material was detected, and BDV antigens discovered in archival animal brains using established immunohistology. Thus, based on several independent methods, both CPXV and BDV (or a closely related agent) were shown to be present in Finland. Bank voles could be productively infected with BDV. This experimental infection did not result in notable pathological findings or symptoms, despite the intense spread of the virus in the central and peripheral nervous system. Infected voles commonly excreted the virus in urine and faeces, which emphasises their possible role as a BDV reservoir. Moreover, BDV RNA was regularly reverse transcribed into DNA in bank voles, which was detected by amplifying DNA by PCR without reverse transcription, and verified with nuclease treatments. This finding indicates that BDV genes could be endogenized during an acute infection. Although further transmission studies are needed, this experimental infection demonstrated that the bank vole can function as a potential BDV reservoir. In summary, multiple methods were established and applied in large panels to detect two zoonoses novel to Finland: cowpox virus and Borna disease virus. Moreover, new information was obtained on their geographical distribution, host spectrum, epidemiology and infection kinetics.

Effect of colostrum feeding method and presence of dam on the sleep, rest and sucking behaviour of newborn calves

"In rats, sucking milk reduces anxiety and promotes non-rapid eye movement (NREM) sleep, and in calves it induces resting but the effect on sleep is unknown. Here, we investigated how calves' sleep was affected by colostrum feeding methods. Forty-one calves were blocked by birth date and randomly allotted within blocks to the experimental treatments. Calves were housed for four days either with their dam (DAM) or individually with warm colostrum feeding (2 L four times a day) from either a teat bucket (TEAT) or an open bucket (BUCKET). DAM calves suckled their dam freely. Calves' sleeping and sucking behaviour was filmed continuously for 48 h at the ages of two and three days. Behavioural sleep (BS) was defined as calves resting at least 30 s with their head still and raised (non-rapid eye movement) or with their head against their body or the ground (rapid eye movement, REM). Latency from the end of colostrum feeding to the start of BS was recorded. We compared behaviour of TEAT calves with that of DAM and BUCKET calves using mixed models. Milk meal duration was significantly longer for TEAT calves than for BUCKET calves (mean +/- S.E.M.; 8.3 +/- 0.6 min vs. 5.2 +/- 0.6 min), but equal to that of DAM calves. We found no effect of feeding method on the duration of daily BS (12 h 59 min I h 38 min) but we found a tendency for the daily amount of NREM sleep; BUCKET calves had less NREM sleep per day than TEAT calves (6 h 18 min vs. 7 h 48 min, S.E.M. = 45 min) and also longer latencies from milk ingestion to BS (21.9 +/- 2.0 min vs. 16.2 +/- 2.0 min). DAM calves slept longer bouts than TEAT calves (10.8 +/- 1.0 min vs. 8.3 +/- 1.0 min) and less often (78 +/- 4 vs. 92 +/- 4). Sucking colostrum from a teat bucket compared with drinking from an open"