1574 Does Use of Intra-Operative PPE Affect Post-Operative Infection Rates in Hip Fracture Patients?

Aim

COVID-19 has required significant change to theatre protocol. Regional guidelines dictate full PPE must be donned for all procedures where aerosol generating procedures (AGP) occur. Additionally, no one may enter or leave theatre whilst an operation is in progress, or until 20 minutes after an AGP. We hypothesized that adopting these protocols may lead to a reduction in post-operative infection in hip fracture patients.

Method

Multicentre retrospective cohort study comparing post-operative infection and return to theatre rates (<30-days post-op) from 18/03/20 to 27/04/20 with respective period in 2019. COVID-19 was considered endemic in Northern Ireland from 18/03/20. Patients were identified from the Fracture Outcomes Research Department database and relevant inpatient episode reviewed via Electronic Care Record.

Results

464 patients were included– 261(2020) and 203(2019). In 2019, 4 patients (1.5%) returned to theatre within 30-days, however only one was due to wound dehiscence. In 2020, 1 patient (0.5%) returned to theatre for traumatic wound dehiscence, however they had no documented infection.

Conclusions

There was no difference in post-operative complication rate requiring return to theatre within 30 days between cohorts. Whilst PPE can be considered important for protection of patients and staff against COVID-19, it may not have significant effect on post-operative infection rates.

1622 Peri-Operative Blood Use in Upper GI Surgery

Aim

One group and hold sample costs approximately £18 to process while it costs £170 to prepare and administer 1 unit of cross matched blood. We aimed to quantify the amount of blood cross-matched for elective oesophagectomy and gastrectomy cases and compare this to the number of units transfused.

Method

Retrospective cohort study comparing number of crossmatched blood units requested. Baseline data collected over a 10-week period (08/07/19-16/09/19). A new blood ordering protocol made in agreement with oesophago-gastric and anaesthetic consultants with criteria for blood ordering. Blood was only to be requested if: antibodies on group and hold, pre-op Hb &lt; 120g/l, operative team concerns or previous radiotherapy. Data recollected using the same parameters post -intervention over a 10-week period (23/12/19-08/03/20).

Results

Pre-intervention 24 patients were included, mean age 67. 47 units were requested with only 1 transfused. Post intervention 27 patients were included, mean age 69. 36 units were ordered and 3 transfused. The new protocol was correctly implemented in 19 patients (70%) therefore saving a potential of 24 units and approximately £4080.

Conclusions

Patients were cross matched far in excess of their transfusion needs. There was significant reduction in the number of patients being cross-matched post intervention. Rationalising this is important to reduce waste, reduce cost and cut down on delays to maximise theatre time.

Use of the Atlantic nut clam (Nucula proxima) and catworm (Nephtys incisa) in a sentinel species approach for monitoring the health of Bay of Fundy estuaries

Designing an effective environmental monitoring system for population responses requires knowledge of the biology of appropriate sentinel species and baseline information on the area's physical and chemical characteristics. This study collected information in Saint John Harbor, NB, Canada, for two abundant marine benthic invertebrates, the Atlantic nut clam (Nucula proxima) and the catworm (Nephtys incisa) to characterize their seasonal and spatial variability, determine the ideal sampling time and methods, and develop baseline data for future studies. We also evaluated whether contamination is impacting invertebrates by comparing sediment metal concentrations to responses of benthic infauna. Metals were generally below sediment quality guidelines except for nickel and arsenic. Clam densities were variable between sites but not seasons, whereas catworm densities were not significantly different between sites or seasons. Overall, these species show potential for environmental monitoring, although investigation at more contaminated sites is warranted to assess their sensitivity.

Pharmacological and signalling properties of a D2-like dopamine receptor (Dop3) in Tribolium castaneum

Dopamine is an important neurotransmitter in the central nervous system of vertebrates and invertebrates. Despite their evolutionary distance, striking parallels exist between deuterostomian and protostomian dopaminergic systems. In both, signalling is achieved via a complement of functionally distinct dopamine receptors. In this study, we investigated the sequence, pharmacology and tissue distribution of a D2-like dopamine receptor from the red flour beetle Tribolium castaneum (TricaDop3) and compared it with related G protein-coupled receptors in other invertebrate species. The TricaDop3 receptor-encoding cDNA shows considerable sequence similarity with members of the Dop3 receptor class. Real time qRT-PCR showed high expression in both the central brain and the optic lobes, consistent with the role of dopamine as neurotransmitter. Activation of TricaDop3 expressed in mammalian cells increased intracellular Ca(2+) signalling and decreased NKH-477 (a forskolin analogue)-stimulated cyclic AMP levels in a dose-dependent manner. We studied the pharmacological profile of the TricaDop3 receptor and demonstrated that the synthetic vertebrate dopamine receptor agonists, 2 - amino- 6,7 - dihydroxy - 1,2,3,4 - tetrahydronaphthalene hydrobromide (6,7-ADTN) and bromocriptine acted as agonists. Methysergide was the most potent of the antagonists tested and showed competitive inhibition in the presence of dopamine. This study offers important information on the Dop3 receptor from Tribolium castaneum that will facilitate functional analyses of dopamine receptors in insects and other invertebrates.

Characterisation of a functional allatotropin receptor in the bumblebee, Bombus terrestris (Hymenoptera, Apidae)

Allatotropins (ATs) are multifunctional neuropeptides initially isolated from the tobacco hornworm, Manduca sexta, where they were found to stimulate juvenile hormone synthesis and release from the corpora allata. ATs have been found in a wide range of insects, but appear to be absent in Drosophila. The first AT receptor (ATR) was characterised in 2008 in the lepidopteran Bombyx mori. Since then ATRs have been characterised in Coleoptera and Diptera and in 2012, an AT precursor gene was identified in hymenopteran species. ATRs show large sequence and structural similarity to vertebrate orexin receptors (OXR). Also, AT in insects and orexin in vertebrates show some overlap in functions, including modulation of feeding behaviour and reproduction. The goal of this study was to identify a functional ATR in a hymenopteran species. We used ATRs (insect sequences) and OXRs (vertebrate sequences) to search the genome of the bumblebee, Bombus terrestris. Two receptors (XP_003402490 and XP_003394933) with resemblance to ATRs and OXRs were found. Phylogenetic analysis provided the first indication that XP_003402490 was more closely related to ATRs than XP_003394933. We investigated the transcript level distribution of both receptors and the AT precursor gene by means of quantitative real-time reverse transcriptase PCR. XP_003402490 displayed a tissue distribution comparable with ATRs in other species, with high transcript levels in the male accessory glands. After pharmacological characterisation, it appeared that XP_003402490 is indeed a functional ATR. Activation of the receptor causes an increase in intracellular calcium and cyclic AMP levels with an EC50 value in the low nanomolar to picomolar range. XP_003394933 remains an orphan receptor.

Relationship of selection criteria to subsequent academic performance in an Australian undergraduate dental school

In 1998, in addition to previous academic achievement, an aptitude test (UMAT) and a structured interview were introduced into selection for the Bachelor of Dental Science (BDSc), the undergraduate dental course at the University of Western Australia. The aim of this study was to determine the relationship between the combination of school-leaver dental students' entry scores, some demographic characteristics and subsequent student performance in the undergraduate course. Three hundred and ninety-eight school-leavers who enrolled in the BDSc from 1999 through 2011 were studied. Regression models were constructed comprising entry scores, gender and age as predictors in relation to subsequent academic performance. The main outcome measure was the weighted average mark (WAM) for each of five academic year levels as well as results in specific units, defined as either 'knowledge' based or 'clinically' based. Of the variables studied, previous academic performance and female gender had the strongest relationship with yearly WAM for Years 1 through 4 and for both 'knowledge' based and 'clinically' based units. The interview score showed a strong relationship in the major clinical years and in a range of 'clinically' based units. UMAT scores were less consistent in relationship to WAM. These results support assessment through a highly structured interview together with prior academic achievement as an evidence-based approach to selection of students for this undergraduate dental course.

Age-related changes in the behavioural response of honeybees to Apiguard®, a thymol-based treatment used to control the mite Varroa destructor

The parasitic mite Varroa destructor is responsible for heavy losses in honey bee colonies and represents a major threat to the beekeeping industry. Essential oils offer an attractive alternative to the use of synthetic chemicals for the control of varroa. Amongst them, thymol appears to be particularly promising. However, treatments using thymol as their active substance, such as the gel formulation Apiguard(®), are suspected to have adverse effects on honey bee colonies. In this study, laboratory assays are used to investigate the effects of Apiguard(®) exposure on honey bee behaviour. Our results reveal that honey bee responses to this anti-varroa treatment change with honey bee age. While 2-day-old bees respond neutrally to Apiguard(®), older bees generally avoid the Apiguard(®) gel. Responses of forager bees were particularly striking. Foragers appear to be repelled by Apiguard(®). Touching their antennae with Apiguard(®) induces robust fanning behaviour. Our data suggest, however, that forager bees exposed to Apiguard(®) in the hive can become habituated to this treatment. These results offer interesting new perspectives on the effects of Apiguard(®) on honey bee behaviour and serve to highlight age-related changes in honey bee responses to gustatory, as well as olfactory cues.

PACAP38 increases vesicular monoamine transporter 2 (VMAT2) expression and attenuates methamphetamine toxicity

Pituitary adenylyl cyclase activating polypeptide, 38 amino acids (PACAP38) is a brain-gut peptide with diverse physiological functions and is neuroprotective in several models of neurological disease. In this study, we show that systemic administration of PACAP38, which is transported across the blood-brain barrier, greatly reduces the neurotoxicity of methamphetamine (METH). Mice treated with PACAP38 exhibited an attenuation of striatal dopamine loss after METH exposure as well as greatly reduced markers of oxidative stress. PACAP38 treatment also prevented striatal neuroinflammation after METH administration as measured by overexpression of glial fibrillary acidic protein (GFAP), an indicator of astrogliosis, and glucose transporter 5 (GLUT5), a marker of microgliosis. In PACAP38 treated mice, the observed protective effects were not due to an altered thermal response to METH. Since the mice were not challenged with METH until 28 days after PACAP38 treatment, this suggests the neuroprotective effects are mediated by regulation of gene expression. At the time of METH administration, PACAP38 treated animals exhibited a preferential increase in the expression and function of the vesicular monoamine transporter (VMAT2). Genetic reduction of VMAT2 has been shown to increase the neurotoxicity of METH, thus we propose that the increased expression of VMAT2 may underlie the protective actions of PACAP38 against METH. The ability of PACAP38 to increase VMAT2 expression suggests that PACAP38 signaling pathways may constitute a novel therapeutic approach to treat and prevent disorders of dopamine storage.

Invertebrate D2 type dopamine receptor exhibits age-based plasticity of expression in the mushroom bodies of the honeybee brain

We have isolated a cDNA clone from the honeybee brain encoding a dopamine receptor, AmDop2, which is positively coupled to adenylyl cyclase. The transmembrane domains of this receptor are 88% identical to the orthologous Drosophila D2 dopamine receptor, DmDop2, though phylogenetic analysis and sequence homology both indicate that invertebrate and vertebrate D2 receptors are quite distinct. In situ hybridization to mRNA in whole-mount preparations of honeybee brains reveals gene expression in the mushroom bodies, a primary site of associative learning. Furthermore, two anatomically distinct cell types in the mushroom bodies exhibit differential regulation of AmDop2 expression. In all nonreproductive females (worker caste) and reproductive males (drones) the receptor gene is strongly and constitutively expressed in all mushroom body interneurons with small cell bodies. In contrast, the large cell-bodied interneurons exhibit dramatic plasticity of AmDop2 gene expression. In newly emerged worker bees (cell-cleaning specialists) and newly emerged drones, no AmDop2 transcript is observed in the large interneurons whereas this transcript is abundant in these cells in the oldest worker bees (resource foragers) and older drones. Differentiation of the mushroom body interneurons into two distinct classes (i.e., plastic or nonplastic with respect to AmDop2 gene expression) indicates that this receptor contributes to the differential regulation of distinct neural circuits. Moreover, the plasticity of expression observed in the large cells implicates this receptor in the behavioral maturation of the bee.

Duplication of chromosome 2 in association with ventriculomegaly - a case report

This is a case report of the prenatal diagnosis of a de novo interstitial duplication of chromosome 2 (46,XX,dup(2)(p13p21) de novo) with an associated phenotypic abnormality. This chromosomal duplication is rare, only one has previously been described prenatally. Postnatal reports of similar duplications in this region have described associated dysmorphic features and significant neurodevelopmental delay. In our case, the only ultrasound finding was moderately severe ventriculomegaly. At post-mortem, ventriculomegaly was confirmed and there was associated macrocephaly (head circumference above the 97th centile) with no dysmorphic features seen.

Cannabinoid receptors are absent in insects

The endocannabinoid system exerts an important neuromodulatory role in mammals. Knockout mice lacking cannabinoid (CB) receptors exhibit significant morbidity. The endocannabinoid system also appears to be phylogenetically ancient--it occurs in mammals, birds, amphibians, fish, sea urchins, leeches, mussels, and even the most primitive animal with a nerve network, the Hydra. The presence of CB receptors, however, has not been examined in terrestrial invertebrates (or any member of the Ecdysozoa). Surprisingly, we found no specific binding of the synthetic CB ligands [(3)H]CP55,940 and [(3)H]SR141716A in a panel of insects: Apis mellifera, Drosophila melanogaster, Gerris marginatus, Spodoptera frugiperda, and Zophobas atratus. A lack of functional CB receptors was confirmed by the inability of tetrahydrocannabinol (THC) and HU210 to activate G-proteins in insect tissues, utilizing a guanosine-5'-O-(3-[(35)]thio)-triphosphate (GTP gamma S) assay. No orthologs of human CB receptors were located in the Drosophila genome, nor did we find orthologs of fatty acid amide hydrolase. This loss of CB receptors appears to be unique in the field of comparative neurobiology. No other known mammalian neuroreceptor is understood to be missing in insects. We hypothesized that CB receptors were lost in insects because of a dearth of ligands; endogenous CB ligands are metabolites of arachidonic acid, and insects produce little or no arachidonic acid or endocannabinoid ligands, such as anandamide.

Sequence and functional analysis of a homolog of interleukin-10 encoded by the parapoxvirus orf virus

Orf virus is a large DNA virus and is the type species of the Parapoxvirus genus of the family Poxviridae. Orf virus infects the epithelium of sheep and goats and is transmissible to humans. Recently we discovered a gene in orf virus that encodes a polypeptide with remarkable homology to mammalian interleukin (IL-10) and viral encoded IL-10s of herpes viruses. The predicted polypeptide sequence shows high levels of amino acid identity to IL-10 of sheep (80%), cattle (75%), humans (67%) and mice (64%), as well as IL-10-like proteins of Epstein-Barr virus (63%) and equine herpes virus (67%). The C-terminal region, comprising two-thirds of the orf virus protein, is identical to ovine IL-10 which suggests that this gene has been captured from its host sheep during the evolution of orf virus. In contrast the N-terminal region shows little homology with cellular IL10s and in this respect resembles other viral IL-10s. IL-10 is a pleiotrophic cytokine that can exert either immunostimulatory or immunosuppressive effects on many cell types. IL-10 is a potent anti-inflammatory cytokine with inhibitory effects on non-specific immunity in particular macrophage function and Thl effector function. Our studies so far, indicate, that the functional activities of orf virus IL-10 are the same as ovine IL-10. Orf virus IL-10 stimulates mouse thymocyte proliferation and inhibits cytokine synthesis in lipopolysaccharide-activated ovine macrophages, peripheral blood monocytes and keratinocytes. Infection of sheep with an IL-10 deletion mutant of orf virus has shown that interferon-gamma levels are higher in tissue infected with the mutant virus than the parent virus. The functional activities of IL-10 and our data on orf virus IL-10 suggest a role in immune evasion.

Orf virus encodes a novel secreted protein inhibitor of granulocyte-macrophage colony-stimulating factor and interleukin-2

The parapoxvirus orf virus encodes a novel soluble protein inhibitor of ovine granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-2 (IL-2). The GM-CSF- and IL-2-inhibitory factor (GIF) gene was expressed as an intermediate-late viral gene in orf virus-infected cells. GIF formed homodimers and tetramers in solution, and it bound ovine GM-CSF with a K(d) of 369 pM and ovine IL-2 with a K(d) of 1.04 nM. GIF did not bind human GM-CSF or IL-2 in spite of the fact that orf virus is a human pathogen. GIF was detected in afferent lymph plasma draining the skin site of orf virus reinfection and was associated with reduced levels of lymph GM-CSF. GIF expression by orf virus indicates that GM-CSF and IL-2 are important in host antiviral immunity.

Feasibility of hospital-based blood banking: a Tanzanian case study

The demand for blood transfusion is high in sub-Saharan Africa because of the high prevalence of anaemia and pregnancy related complications, but the practice is estimated to account for 10% of HIV infections in some regions. The main response to this problem by the international donor community is to establish vertically implemented blood transfusion services producing suitable (safe) blood at a cost of US$25-40 per unit. However, the economic sustainability of such interventions is questionable and it is argued here that hospital-based blood transfusion services operating at a basic adequate level are sufficient for low-income African countries. The results of a project aimed at improving such services in Tanzania are presented. The main findings are: (1) the cost per suitable blood unit produced was US$12.4; (2) at an HIV test sensitivity of 93.5% during the study period, discounted financial benefits of the interventions exceeded costs by a factor of between 17.2 and 37.1; (3) the cost per undiscounted year of life saved by use of these interventions was US$2.7-2.8; and (4) safe blood transfusion practices can be assured at an annual cost of US$0.07 per capita. Recommendations are made to ensure safe blood transfusion practices at hospital-based blood banks in Tanzania.

Autoradiographic localisation of [3H]-SCH23390 and [3H]-spiperone binding sites in honey bee brain

In the brain of the honey bee, dopamine receptors have been identified by using the vertebrate D1 dopamine antagonist [3H]-SCH23390 and the vertebrate D2 dopamine antagonist [3H]-spiperone. This study uses light microscope autoradiography to investigate the anatomical distributions of the binding sites labelled by [3H]-SCH23390 and [3H]-spiperone in tissue sections cut at three depths from the anterior surface of the brain. The binding of these radioligands differed significantly, in both density and distribution. Specific binding of [3H]-SCH23390, defined by using 5 x 10(-6) M cis-(Z)-flupentixol, was densest in regions of somata, such as the deutocerebral somatal rind, the somatal layer beneath the calyces of the mushroom bodies and the ventral protocerebral somatal group. High levels of [3H]-SCH23390 binding were also measured in the lateral protocerebrum. [3H]-Spiperone binding site density estimates were consistently lower than those of [3H]-SCH23390. Specific binding of [3H]-spiperone, determined by subtracting binding in the presence of 10(-4) M domperidone from the total binding, was highest in the alpha lobes, beta lobes, and calyces of the mushroom body neuropil. Relatively high binding was also measured in the central body and lateral protocerebral neuropil. These results suggest that the distribution of dopamine receptors in the brain of the bee is subtype specific, and they support the view that dopamine plays many roles in the insect central nervous system.

The orf virus OV20.0L gene product is involved in interferon resistance and inhibits an interferon-inducible, double-stranded RNA-dependent kinase

The parapoxvirus orf virus was resistant to type 1 (IFN-alpha) and type 2 (IFN-gamma) interferons in cultures of ovine cells. The recently identified orf virus OV20.0L gene exhibits 31% predicted amino acid identity to the vaccinia virus E3L interferon-resistance gene, and is referred to as the (putative) orf virus interferon-resistance gene (OVIFNR). The objective of this study was to determine whether OVIFNR was involved in interferon resistance. Recombinant OVIFNR as a thioredoxin fusion protein (OVIFNR-Tx) inhibited the activation (by autophosphorylation) of an interferon-inducible, double-stranded (ds) RNA-dependent kinase (PKR) of sheep, which was shown to bind dsRNA (poly I:C). PKR in other species is involved in the inhibition of protein synthesis as part of the antiviral state in infected cells. Virus-infected cell lysates, but not control lysates, from cells grown in the presence of cytosine arabinoside also contained PKR inhibitory activity, which indicated that the inhibitory activity was associated with early viral gene expression. Significantly, the OVIFNR gene expressed in interferon-treated ovine fibroblasts protected the unrelated Semliki Forest virus from the antiviral effect of both type 1 and type 2 interferons. Taken together, the results indicate that the OVIFNR gene functions as an interferon-resistance gene, the product of which inhibits PKR in a similar way to the vaccinia virus E3L gene product.

Venous thromboembolism associated with air travel: a report of 33 patients

BACKGROUND

The medical literature suggests long distance travel, particularly air travel, may be a risk factor for venous thromboembolism, but the risk is poorly quantified.

METHODS

We reviewed 134 records of patients hospitalized with venous thromboembolism for comments regarding recent travel. Patients who had traveled within 31 d prior to venous thromboembolism were defined as recent travelers.

RESULTS

Of 134 patients records, 66 (49%) had documented inquiries regarding travel and 33 (50%) were recent air travelers. Data regarding demographics, mode of travel, day of onset of symptoms in relation to travel, and other risk factors for venous thromboembolism were abstracted from the records of the recent travelers. There were 12 (36%) travelers who had no other predisposition for venous thromboembolism. All had traveled non-stop by aircraft for 4 or more hours; none was identified as a crew-member. The median day of onset of venous thromboembolism was on travel day 4 (range: day 1-31). There were 8 (24%) patients who had onset during air travel or on the day of arrival, and 27 (82%) had onset by travel day 15. Air travel for 4 or more hours within the preceding 31 d was the most common risk factor for venous thromboembolism in our study patients and was present in 50%. This incidence is much higher than previously described, perhaps due to limiting the study population to those in which the presence or absence of travel was documented.

CONCLUSION

Prospective studies are needed to better define the risk factors for venous thromboembolism among long distance air passengers and crew-members, and to determine effective preventive measures.

Molecular genetic analyses of parapoxviruses pathogenic for humans

The current members of the genus parapoxvirus are orf virus (ORFV), bovine papular stomatitis virus (BPSV), pseudocowpoxvirus (PCPV) and parapoxvirus of red deer in New Zealand (PVNZ). BPSV and PCPV are maintained in cattle while ORFV is maintained in sheep and goats, but all three are zoonoses. Only the recently reported PVNZ has yet to be recorded as infecting humans. Tentative members of the genus are camel contagious ecthyma virus, chamois contagious ecthyma virus and sealpoxvirus. The separation of the parapoxviruses into 4 distinct groups has been based on natural host range, pathology and, more recently, on restriction endonuclease and DNA/DNA hybridisation analyses. The latter studies have shown that the parapoxviruses share extensive homology between central regions of their genomes, but much lower levels of relatedness within the genome termini. The high G + C content of parapoxvirus DNA is in contrast to most other poxviruses and suggests that a significant genetic divergence from other genera of this family has occurred. DNA sequencing of portions of the genome of ORFV, the type species of the genus, has allowed a detailed comparison with the fully sequenced genome of the orthopoxvirus, vaccinia virus (VACV). These studies have provided a genetic map of ORFV and revealed a central core of 88 kbp within which the genomic content was strikingly similar to that of VACV. This conservation is not maintained in the genome termini where insertions, deletions and translocations have occurred. The characterisation of specific ORFV genes may lead to the construction of attenuated vaccine strains in which genes such as those with the potential to interfere with the immune response of the host have been deleted. The current ORFV vaccines are living unattenuated virus and vaccination lesions produce virus which contaminates the environment in a manner similar to natural infection. The virus in scab material is relatively resistant to inactivation and this virus both perpetuates the disease in sheep and provides the most likely source of human infections. A vaccine which immunises animals without perpetuating the disease could be the best way of reducing the incidence of ORFV infection of humans. It is likely that protection against infection by ORFV is cell mediated and will require the endogenous production of relevant antigens. We have recently constructed a series of VACV recombinants each of which contains a large multigene fragment of ORFV DNA. Together the recombinants represent essentially all of the ORFV genome in an overlapping manner. Vaccination of sheep with the recombinant library provided protection against challenge with virulent ORFV. Further studies with this library may enable dominant protective antigens of ORFV to be identified and lead to their incorporation into a subunit vaccine.

The immune and inflammatory response to orf virus

Orf virus is a zoonotic, epitheliotropic DNA parapox virus that principally infects sheep and goats. The fact that the virus can repeatedly reinfect sheep has provoked an interest in the underlying cellular, virological and molecular mechanisms for its apparent escape from the host protective immune response. The local immune and inflammatory response in skin and the cell phenotype and cytokine response in lymph analysed around a single lymph node are characteristic of an anti-viral response. An unusual feature is the dense accumulation of MHC Class II+ dendritic cells in the skin lesion. The function of these cells is not known. Orf virus virulence genes and activities have been identified that may interfere with the development of the host protective immune and inflammatory response.

Cytokines and their inhibitors in orf virus infection

The epitheliotropic parapoxvirus, orf virus, can repeatedly infect sheep skin. A specific immune response is generated as reinfections induce smaller lesions with quicker resolution times than primary lesions. Cyclosporin-A treatment abrogates this partial immunity. Cytokine mRNAs detected in lesion biopsies include the transcripts for IL-1 beta, IL-3 GM-CSF, TNF-alpha and, less reproducibly, IFN-gamma. CD4+ T-cells predominate in afferent lymph draining the site of infection, and are the major source of GM-CSF and IFN-gamma. IL-1 beta and IL-8 are also detected. The orf virus genome contains a homologue of mammalian vascular endothelial growth factor that may enhance virulence and a vaccinia virus E3L-like gene which may inhibit the anti-viral effect of the interferons. A GM-CSF inhibitory activity has also been discovered and has been 'chased' into a 10 kb DNA segment of the orf virus genome. These studies indicate that orf virus may temporarily avoid host immunity by a combination of acute, rapid infection and replication in the epidermis and by producing virulence factors that inhibit protective proteins of the host immune and inflammatory response.

Pharmacological dissociation of different forms of synaptic plasticity in the marine mollusc Aplysia

The actions of the neuromodulator serotonin (5HT) in Aplysia sensory neurons can be dissociated on the basis of their sensitivity to 5HT receptor antagonist cypropheptadine, and their concentration requirement to 5HT. Here we summarise a series of experiments that suggest that mechanically distinct processes contribute to the different physiological components of short- and long-term synaptic plasticity.

Mortality and morbidity in refugee camps in eastern Sudan: 1985-90

Civil war has disrupted life in Ethiopia since the 1960s and many people have sought refuge in Eastern Sudan, particularly during the famine emergency of 1984-85. UNHCR has provided the main financial support for the refugee programme, but began scaling down operations in 1990. Nearly 300,000 refugees still live in camps and benefit from food and health programmes. Health services are co-ordinated by the Sudanese Refugee Health Unit which operates a centralised health and nutrition surveillance system with the co-operation of the NGOs responsible for health care in the camps. A revision of the monthly reporting system and the establishment of a computer database in 1990 provided an opportunity to review the situation in the camps over the five years since the emergency. Child death rates for example, appear to have been reduced to levels below those expected in rural Africa. Patterns of mortality, morbidity, and nutritional status are outlined here and point to the general effectiveness of the health care programme. The surveillance system can, however, be used to identify those camps which have persistent problems, while monthly comparisons with the situation in previous years can provide early warning of deteriorating conditions.

Evaluation of a predictive mathematical model of di-(2-ethylhexyl) adipate plasticizer migration from PVC film into foods

The diffusion coefficient of the plasticizer di-(2-ethylhexyl)adipate (DEHA) in Cheddar cheese (Df) was determined by measuring the extent to which DEHA penetrated cheese that was placed in intimate contact with artificially DEHA-contaminated cheese. Slices (20 microns) of cheese from the boundary layer, into which DEHA had migrated, were microtomed at -40 degrees C, and analyzed for DEHA by gas chromatography (GC). Mean values of Df determined by graph fitting experimental and calculated data were 1.5 x 10(-9) cm2 s-1 at 5 degrees C and 3.0 x 10(-8) cm2 s-1 at 25 degrees C. The partition coefficient (K) of DEHA between cheese and PVC film was derived from the partition coefficients of DEHA between acetonitrile (ACN) and cheese lipid, ACN and cheese solid, and ACN and PVC film. The mean values of K between cheese and PVC film were estimated to be 0.70 at 5 degrees C and 0.58 at 25 degrees C. The estimated values of Df and K were then used in a mathematical model (Till et al. 1982) to predict migration levels of DEHA into cheese. Good agreement with previously published experimental data was obtained. Extrapolation of the prediction of DEHA migration into fatty foods, such as salami and avocado, was also successful (ratio of experimental to predicted results within a factor of two). The values of Df and K for cheese are, however, inappropriate for modelling non-fatty foods such as meat, cakes, fruit and vegetables. Predicted values for these foods were typically 3-10-fold too high. More accurate predictions would probably be obtained if values of Df more relevant to these foods are used. The predictions were relatively insensitive to the value of K.

Wolf-Hirschhorn locus is distal to D4S10 on short arm of chromosome 4

We report a family in which Wolf-Hirschhorn syndrome in two children with partial monosomy of the short arm of chromosome 4 is the result of unbalanced segregation of a reciprocal 4;12 translocation in the mother. Studies with the DNA probe G8 show that the translocation breakpoint in this family is distal to the D4S10 locus. Previously reported cases of Wolf-Hirschhorn syndrome have involved the deletion of D4S10. These observations may prove helpful in the search for better genetic markers for Huntington's chorea, which maps close to D4S10.

Monopolies, Maricopa, and marketing: a case study

The development of preferred provider organizations in recent years has caused significant concerns about the antitrust implications of these new organizational arrangements among healthcare providers. The potential of being accused of price-fixing, monopolistic, or anti-competitive activity has concerned many health professionals involved in establishing PPOs. This article presents the nature of some of the antitrust arguments and a few representative cases demonstrating various rulings about the anti-competitive elements present or absent from various PPO arrangements. In addition, selected state and federal legislation concerning PPOs is discussed. In addition to understanding the antitrust issues involved in PPOs, establishing a PPO also requires the active involvement of the various key players in determining structural and pricing arrangements. The case study presented here demonstrates the use of marketing principles which emphasize the importance of participation and communication in decision making with physicians in the formation of a PPO.

Lipopolysaccharide, capsule, and fimbriae as virulence factors among O1, O7, O16, O18, or O75 and K1, K5, or K100 Escherichia coli

K1, K5, and K100 Escherichia coli isolates of the lipopolysaccharide antigen types O1, O7, O16, O18, or O75, which had formerly been assigned to clonal groupings were compared with K? E. coli isolates and with laboratory-derived mutants defective in capsule or lipopolysaccharide synthesis. The amount of K1 capsule, the length distribution of the lipopolysaccharide, and the expression of type I and P fimbriae were determined. The clonal groupings were uniform with regard to these properties within each group but different from each other. Many of the K? strains differed from the clonal representatives. The results are interpreted with regard to the different diseases caused by each of these bacterial groups.

Induction of bacteremia in newborn rats by Escherichia coli K1 is correlated with only certain O (lipopolysaccharide) antigen types

A total of 95 Escherichia coli strains (O1:K1, O7:K1, or O18:K1), obtained from different sources of human infections and from healthy individuals, were analyzed for the ability to cause bacteremia after colonizing the gut of newborn rats. Strains of all three serotypes were able to multiply extensively in the gut after oral inoculation and to translocate (in small numbers) to the mesenteric lymph nodes. With only few exceptions, O7:K1 and O18:K1 strains were able to cause bacteremia, while O1:K1 strains could not. Mixed-infection experiments revealed that the bacteria present in the blood during a case of bacteremia are in most cases the descendants of one cell that has multiplied extraintestinally after translocation to the mesenteric lymph nodes. It appears that virulent O7:K1 and O18:K1, but not avirulent O1:K1, bacteria are able to multiply directly in the bloodstream of the newborn rats. No correlation between virulence and the source of isolation of the different strains was observed. Disease isolates thus do not seem to differ from fecal isolates of the same serotype in special virulence properties. The differences in virulence among different O serotypes of K1 E. coli observed in the rat model were comparable to their relative frequency of isolation from meningitis in newborn children.

Six widespread bacterial clones among Escherichia coli K1 isolates

Variable properties among Escherichia coli isolates include serotype, electrophoretic migration of major outer membrane proteins, metabolic properties, production of hemolysin or colicin or both, and plasmid content. These characteristics were compared in E. coli strains of capsular types K1, K5, K92, and K100 and in non-encapsulated isolates. The 234 bacterial strains from the United States and Europe which we studied had been isolated from healthy or diseased individuals recently or as long ago as 1941. Regardless of source, most O7:K1, O16:K1, and O75:K100 isolates could be assigned to three unique, serotype-specific groups, which were interpreted as representing three bacterial clones. Two bacterial (sub)clones each were discerned among the O18:K1 and O18:K5 isolates, and two further, distinct clones were discerned among the O1:K1 isolates. The implications of these results for epidemiological analyses and for virulence are discussed.