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1.
Vaccine ; 41(41): 5919-5924, 2023 09 22.
Article in English | MEDLINE | ID: mdl-37633751

ABSTRACT

The Covid pandemic took the world by surprise in late 2019 and the need for rapid development of vaccines became paramount. The challenge was how to accelerate standard vaccine development times as much as possible. With knowledge of the genetic code of SARsCOV2, vaccine manufacturers throughout the world have risen to the challenge and several new vaccines were rapidly developed for emergency use. In March 2020, global Regulatory Authorities met to consider how to start early clinical trials and accept rolling submissions. Before use in clinical trials or any mass vaccination campaigns, the safety of the candidate vaccine needs to be evaluated. Non-clinical toxicology studies are required as an important part of vaccine safety evaluation. The extent of the toxicology evaluation prior to the start of clinical trials depended on several factors, including: the type of the candidate vaccine as well as already available supportive information with the candidate vaccine or similar vaccine types. For vaccine candidates with pre-existing data, this would save valuable time whilst a full toxicology evaluation was completed in parallel. For vaccines with more limited data, toxicology data was required before clinical development could start. This workshop examined the nonclinical toxicology studies for new Covid vaccines from the perspectives of: Vaccine manufacturers with different vaccine technologies, managing global regulatory submissions/responses; CROs, managing the urgency of conducting and reporting studies and supporting new players in the vaccine world; and Regulatory Authorities, in supporting the review process, juggling the need for safety and quality with mounting pressure to approve vaccines.


Subject(s)
COVID-19 Vaccines , COVID-19 , Vaccines , Humans , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , RNA, Viral , SARS-CoV-2
5.
J Small Anim Pract ; 63(1): 27-33, 2022 01.
Article in English | MEDLINE | ID: mdl-34608641

ABSTRACT

OBJECTIVES: To describe the CT appearance of anal sac adenocarcinoma lesions in a population of dogs including the relations between primary tumour, and locoregional and distant metastasis. MATERIALS AND METHODS: Retrospective review of dogs with confirmed anal sac adenocarcinoma and available CT images of the thorax, abdomen and pelvis. RESULTS: A population of 70 dogs were included in the study. No association was found between anal sac mass size and presence or absence of iliosacral lymph node enlargement. The prevalence of local metastatic disease characterised by iliosacral lymphadenomegaly in this study was 71%, with pulmonary metastases identified in 11% of cases. There were no cases of distant pulmonary metastasis without concurrent locoregional lymphadenomegaly. CLINICAL SIGNIFICANCE: In our population of dogs local metastatic spread of anal sac adenocarcinoma was common, with a relatively low prevalence of pulmonary metastasis. The study demonstrates the importance of thorough rectal examination and/or imaging to assess the iliosacral lymph centre in this disease irrespective of the size of the anal sac mass.


Subject(s)
Adenocarcinoma , Anal Gland Neoplasms , Anal Sacs , Dog Diseases , Adenocarcinoma/diagnostic imaging , Adenocarcinoma/pathology , Adenocarcinoma/veterinary , Anal Gland Neoplasms/diagnostic imaging , Anal Sacs/diagnostic imaging , Anal Sacs/pathology , Animals , Dog Diseases/diagnosis , Dogs , Neoplasm Staging , Retrospective Studies , Tomography, X-Ray Computed/veterinary
6.
EJNMMI Phys ; 7(1): 47, 2020 Jul 14.
Article in English | MEDLINE | ID: mdl-32666231

ABSTRACT

An amendment to this paper has been published and can be accessed via the original article.

7.
EJNMMI Phys ; 7(1): 24, 2020 May 05.
Article in English | MEDLINE | ID: mdl-32372135

ABSTRACT

BACKGROUND: Despite the advent of clinical PET-MR imaging for routine use in 2011 and the development of several methods to address the problem of attenuation correction, some challenges remain. We have identified and investigated several issues that might affect the reliability and accuracy of current attenuation correction methods when these are implemented for clinical and research studies of the brain. These are (1) the accuracy of converting CT Hounsfield units, obtained from an independently acquired CT scan, to 511 keV linear attenuation coefficients; (2) the effect of padding used in the MR head coil; (3) the presence of close-packed hair; (4) the effect of headphones. For each of these, we have examined the effect on reconstructed PET images and evaluated practical mitigating measures. RESULTS: Our major findings were (1) for both Siemens and GE PET-MR systems, CT data from either a Siemens or a GE PET-CT scanner may be used, provided the conversion to 511 keV µ-map is performed by the PET-MR vendor's own method, as implemented on their PET-CT scanner; (2) the effect of the head coil pads is minimal; (3) the effect of dense hair in the field of view is marked (> 10% error in reconstructed PET images); and (4) using headphones and not including them in the attenuation map causes significant errors in reconstructed PET images, but the risk of scanning without them may be acceptable following sound level measurements. CONCLUSIONS: It is important that the limitations of attenuation correction in PET-MR are considered when designing research and clinical PET-MR protocols in order to enable accurate quantification of brain PET scans. Whilst the effect of pads is not significant, dense hair, the use of headphones and the use of an independently acquired CT-scan can all lead to non-negligible effects on PET quantification. Although seemingly trivial, these effects add complications to setting up protocols for clinical and research PET-MR studies that do not occur with PET-CT. In the absence of more sophisticated PET-MR brain attenuation correction, the effect of all of the issues above can be minimised if the pragmatic approaches presented in this work are followed.

8.
Proc Biol Sci ; 286(1909): 20191491, 2019 08 28.
Article in English | MEDLINE | ID: mdl-31431166

ABSTRACT

Pyruvate : ferredoxin oxidoreductase (PFO) and iron only hydrogenase ([Fe]-HYD) are common enzymes among eukaryotic microbes that inhabit anaerobic niches. Their function is to maintain redox balance by donating electrons from food oxidation via ferredoxin (Fd) to protons, generating H2 as a waste product. Operating in series, they constitute a soluble electron transport chain of one-electron transfers between FeS clusters. They fulfil the same function-redox balance-served by two electron-transfers in the NADH- and O2-dependent respiratory chains of mitochondria. Although they possess O2-sensitive FeS clusters, PFO, Fd and [Fe]-HYD are also present among numerous algae that produce O2. The evolutionary persistence of these enzymes among eukaryotic aerobes is traditionally explained as adaptation to facultative anaerobic growth. Here, we show that algae express enzymes of anaerobic energy metabolism at ambient O2 levels (21% v/v), Chlamydomonas reinhardtii expresses them with diurnal regulation. High O2 environments arose on Earth only approximately 450 million years ago. Gene presence/absence and gene expression data indicate that during the transition to high O2 environments and terrestrialization, diverse algal lineages retained enzymes of Fd-dependent one-electron-based redox balance, while the land plant and land animal lineages underwent irreversible specialization to redox balance involving the O2-insensitive two-electron carrier NADH.


Subject(s)
Adaptation, Physiological/physiology , Chlamydomonas reinhardtii/physiology , Ferredoxins/metabolism , NAD/metabolism , Anaerobiosis , Animals , Electron Transport , Energy Metabolism , Hydrogenase , Iron-Sulfur Proteins , Oxygen/metabolism
9.
Infection ; 47(5): 811-816, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31073710

ABSTRACT

PURPOSE: Since May 2016, WHO recommended a 9-12 month short-treatment regimen for multidrug-resistant tuberculosis (MDR-TB) treatment known as the 'Bangladesh Regimen'. However, limited data exist on the appropriateness thereof, and its implementation in low- and middle-income countries (LMIC). We report here on the pilot phase of the evaluation of the Bangladesh regimen in Gabon, prior to its endorsement by the WHO. METHODS: This ongoing observational study started in September 2015. Intensive training of hospital health workers as well as community information and education were conducted. GeneXpert-confirmed MDR-TB patients received the second-line anti-tuberculosis drugs (4KmMfxPtoHCfzEZ/5MfxCfzEZ). Sputum smears and cultures were done monthly. Adverse events were monitored daily. RESULTS: Eleven patients have been treated for MDR-TB piloting the short regimen. All were HIV-negative and presented in poor health with extensive pulmonary lesions. The overall sputum culture conversion rate was 64% after 4 months of treatment. Three patients developed marked hearing loss; one a transient cutaneous rash. Of 11 patients in our continuous care, 7 (63.6%) significantly improved clinically and bacteriologically. One (9.1%) patient experienced a treatment failure, two (18.2%) died, and one (9.1%) was lost to follow up. CONCLUSIONS: Our pioneering data on systematic MDR-TB treatment in Gabon, with currently almost total absence of resistance against the second-line drugs, demonstrate that a 9-month regimen has the capacity to facilitate early culture negativity and sustained clinical improvement. Close adverse events monitoring and continuous care are vital to success.


Subject(s)
Antitubercular Agents/administration & dosage , Tuberculosis, Multidrug-Resistant/drug therapy , Tuberculosis, Pulmonary/drug therapy , Adult , Bangladesh , Drug Administration Schedule , Female , Gabon , Humans , Male , Middle Aged , Pilot Projects , Sputum/microbiology , Treatment Failure , Treatment Outcome , Tuberculosis, Multidrug-Resistant/diagnosis , World Health Organization , Young Adult
10.
Clin Microbiol Infect ; 22 Suppl 5: S146-S153, 2016 Dec 01.
Article in English | MEDLINE | ID: mdl-27939015

ABSTRACT

Much has been written about the patient-physician relationship over the years. This relationship is essential in maintaining trust in the complex arena of modern diagnostic techniques, treatment and prevention, including vaccines and vaccine safety. However, a great deal of this material was written from the viewpoint of clinicians and academics. The patient voice may be positive or negative, fragmented or complex. Information sources are weighed and treated differently, according to the value system and risk perceptions of the individual. In post-trust societies, when people have less confidence in health authorities, communication needs to be more than a paternalistic top-down process. Notions of empowerment and individual patient choice are becoming crucial in medical care. The 'voice of the patient', which includes healthy individuals receiving vaccines, needs to be heard, considered and addressed. With respect to childhood immunizations, this will be the voice of the parent or caregiver. The key to addressing any concerns could be to listen more and to develop a communication style that is trust-based and science-informed. Regulatory agencies are encouraging clinical and patient-reported outcomes research under the umbrella of personalized medicine, and this is an important step forward. This paper attempts to reflect the paradigm shift towards increasing attention to the patient voice in vaccination and vaccine safety.


Subject(s)
Vaccination/adverse effects , Vaccines/adverse effects , Vaccines/immunology , Communicable Disease Control , Disease Susceptibility , Dissent and Disputes , Global Health , Health Knowledge, Attitudes, Practice , Humans , Informed Consent , Medication Adherence , Patient Education as Topic , Public Health Administration
11.
Ann R Coll Surg Engl ; 98(2): 107-15, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26673047

ABSTRACT

INTRODUCTION: Emergency general surgery (EGS) accounts for 50% of the surgical workload, and yet outcomes are variable and poorly recorded. The management of acute cholecystitis (AC) at a dedicated emergency surgical unit (ESU) was assessed as a performance target for EGS. METHODS: The outcomes for AC admissions were compared one year before and after inception of the ESU. The impact on cost and compliance with national guidance recommending early laparoscopic cholecystectomy (ELC) within seven days of diagnosis was assessed. RESULTS: The overall ELC rate increased from 26% for the 126 patients admitted in the pre-ESU period to 45% for the 152 patients admitted in the post-ESU period (p=0.001). With those unsuitable for ELC excluded, the ELC rate increased from 34% to 82% (p<0.001). The proportion of patients precluded from ELC for avoidable reasons, particularly owing to 'surgeon preference/skill', was reduced from 69% to 18% (p<0.001). The mean total length of stay (LOS) and postoperative LOS fell by 1.7 days (from 8.3 to 6.6 days, p=0.040) and 2 days (from 5.6 to 3.6 days, p=0.020) respectively. The higher ELC rate and the reduction in LOS produced additional tariff income (£111,930) and estimated savings in bed day (£90,440) and readmission (£27,252) costs. CONCLUSIONS: A dedicated ESU incorporating national recommendations for EGS improves alignment of best practice with best evidence and can also result in financial rewards for a busy district general hospital.


Subject(s)
Cholecystectomy, Laparoscopic/statistics & numerical data , Cholecystitis, Acute/surgery , Emergency Service, Hospital/statistics & numerical data , Length of Stay/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Cholecystectomy, Laparoscopic/economics , Emergency Service, Hospital/economics , Female , Gallstones/surgery , Humans , Length of Stay/economics , Male , Middle Aged , Patient Readmission/economics , Patient Readmission/statistics & numerical data , Postoperative Complications/epidemiology , Young Adult
12.
Ann R Coll Surg Engl ; 97(4): 308-14, 2015 May.
Article in English | MEDLINE | ID: mdl-26263941

ABSTRACT

INTRODUCTION: Emergency surgery is changing rapidly with a greater workload, early subspecialisation and centralisation of emergency care. We describe the impact of a novel emergency surgical unit (ESU) on the definitive management of patients with gallstone pancreatitis (GSP). METHODS: A comparative audit was undertaken for all admissions with GSP before and after the introduction of the ESU over a six-month period. The impact on compliance with British Society of Gastroenterology (BSG) guidelines was assessed. RESULTS: Thirty-five patients were treated for GSP between December 2013 and May 2014, after the introduction of the ESU. This was twice the nationally reported average for a UK trust over a six-month period. All patients received definitive management for their GSP and 100% of all suitable patients received treatment during the index admission or within two weeks of discharge. This was a significantly greater proportion than that prior to the introduction of the ESU (57%, p=0.0001) as well as the recently reported national average (34%). The mean length of total inpatient stay was reduced significantly after the ESU was introduced from 13.7 ± 4.7 days to 7.8 ± 2.1 days (p=0.03). The mean length of postoperative stay also fell significantly from 6.7 ± 2.6 days to 1.8 ± 0.8 days (p=0.001). CONCLUSIONS: A dedicated ESU following national recommendations for emergency surgery care by way of using dedicated emergency surgeons and a streamlined protocol for common presentations has been shown by audit of current practice to significantly improve the management of patients presenting to a busy district general hospital with GSP.


Subject(s)
Emergency Service, Hospital/statistics & numerical data , Gallstones/epidemiology , Gallstones/surgery , Pancreatitis/epidemiology , Pancreatitis/surgery , Adult , Aged , Cholecystectomy , Female , Humans , Male , Middle Aged , Program Evaluation
13.
Lett Appl Microbiol ; 61(4): 381-9, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26218531

ABSTRACT

UNLABELLED: The aim of the study was to compare the antimicrobial activities of freshly made, heat-treated (HT) and 14 day stored (+)-Catechin solutions with (+)-catechin flavanol isomers in the presence of copper sulphate. (+)-Catechin activity was investigated when combined with different ratios of Cu(2+) ; 100°C heat treatment; autoclaving; and 14 day storage against Staphylococcus aureus. Cu(2+) -(+)-Catechin complexation, isomer structure-activity relationships, and H2 O2 generation were also investigated. Freshly made, HT, and 14 day stored flavanols showed no activity. While combined Cu(2+) -autoclaved (+)-Catechin and -HT(+)-Catechin activities were similar, HT(+)-Catechin was more active than either freshly made (+)-catechin (generating more H2 O2 ) or (-)-Epicatechin (though it generated less H2 O2 ) or 14 day-(+)-Catechin (which had similar activity to Cu(2+) controls-although it generated more H2 O2 ). When combined with Cu(2+) , in terms of rates of activity, HT(+)-Catechin was lower than (-)-Epigallocatechin gallate and greater than freshly made (+)-Catechin. Freshly made and HT(+)-Catechin formed acidic complexes with Cu(2+) as indicated by pH and UV-vis measurements although pH changes did not account for antimicrobial activity. Freshly made and HT(+)-Catechin both formed Cu(2+) complexes. The HT(+)-Catechin complex generated more H2 O2 which could explain its higher antimicrobial activity. SIGNIFICANCE AND IMPACT OF THE STUDY: Natural products attract considerable attention in the search for novel antimicrobials, prebiotics and antioxidants. Enhanced biological activity of natural products has been demonstrated with chemical and heat treatment. This article extends the few publications on heat treatments of plant products and combinations with adjuncts, to raise antimicrobial activity against pathogens such as Staphylococcus aureus. We demonstrated that heat treatment could increase the activity of (+)-Catechin, a weak antimicrobial flavanol found commonly in plants in the presence of copper sulphate. Heat treatment of readily available resources merits consideration in the development of more potent substances for use in clinical settings and agriculture.


Subject(s)
Anti-Bacterial Agents/pharmacology , Catechin/pharmacology , Copper Sulfate/chemistry , Hydrogen Peroxide/metabolism , Staphylococcus aureus/drug effects , Anti-Bacterial Agents/chemistry , Catechin/analogs & derivatives , Catechin/chemistry , Copper Sulfate/pharmacology , Hot Temperature , Microbial Sensitivity Tests , Staphylococcus aureus/growth & development , Structure-Activity Relationship
14.
J Anim Sci ; 92(3): 1161-72, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24504043

ABSTRACT

Infectious bovine keratoconjunctivitis (IBK) is a common ocular disease in cattle, associated with a 6.8 to 13.6 kg decrease in weaning weight. Antibiotic therapy is available but it is unclear if pain mitigation as an adjunct therapy would reduce the weight loss associated with IBK. Before assessing the impact of pain mitigation therapies, it is first necessary to validate approaches to qualifying ocular pain. The objective of this study was to evaluate approaches to qualifying ocular pain in bovine calves (Bos taurus) with IBK. Our a priori assumption was that scarification or corneal ulcerations consistent with IBK are painful compared to normal eyes. To quantify this difference in pain, we assessed 4 tools: pressure algometry-mechanical nociceptive threshold (PA-MNT), corneal touch thresholds (CTT) obtained with the use of a Cochet-Bonnet aesthesiometer, and assessment for the presence of blepharospasm and photophobia as metrics for pain. Using a 1-eye randomized controlled challenge trial, 31 calves with healthy eyes were randomly allocated to treatment groups, and then a left or right eye was randomly assigned for corneal scarification and inoculation with Moraxella bovoculi or Moraxella bovis. A repeated measures analysis of variance was used for PA-MNT, with significance set at P < 0.05. A log (base 10) transformation was used to stabilize the variance, and Tukey's t tests were used to test differences between assessment days for each landmark. Calves had statistically significantly lower PA-MNT scores (which indicates more pain) the day after scarification relative to baseline measurements (4 d before scarification). For example, at 1 landmark the median PA-MNT (kg/force) prescarification was 4.82 (95% confidence interval [CI]: 3.92-5.93) and 3.43 (95% CI: 2.79-4.22) postscarification. These data suggest PA-MNT may be a tool for quantifying ocular pain in calves. No differences (P < 0.1) in PA-MNT scores between scarified and not-scarified eyes were detected for any landmark on any day. This result suggests that the pain response occurs over the entire face, not just the affected eye. Corneal ulcerations consistent with IBK were not associated with statistically significant differences in PA-MNT or CTT at eye or calf levels. Not surprisingly, scarified eyes were more likely to exhibit blepharospasm and photophobia compared to healthy eyes. Due to blepharospasm, the use of the Cochet-Bonnet to evaluate corneal sensitivity by CTT was of limited value.


Subject(s)
Cattle Diseases/etiology , Corneal Ulcer/veterinary , Keratoconjunctivitis, Infectious/complications , Pain Measurement/veterinary , Pain/veterinary , Animals , Cattle , Cattle Diseases/microbiology , Cattle Diseases/pathology , Corneal Ulcer/complications , Corneal Ulcer/pathology , Pain Measurement/methods
15.
Anim Health Res Rev ; 15(1): 14-38, 2014 Jun.
Article in English | MEDLINE | ID: mdl-25605277

ABSTRACT

Routine procedures carried out on piglets (i.e. castration, tail docking, teeth clipping, and ear notching) are considered painful. Unfortunately the efficacy of current pain mitigation modalities is poorly understood. The aim of this systematic review was to synthesize the existing primary scientific literature regarding the effectiveness of pain management interventions used for routine procedures on piglets. The review question was, 'In piglets under twenty-eight days old, undergoing castration, tail docking, teeth clipping, and/or methods of identification that involve cutting of the ear tissue, what is the effect of pain mitigation compared with no pain mitigation on behavioral and non-behavioral outcomes that indicate procedural pain and post-procedural pain?' A review protocol was designed a priori. Data sources used were Agricola (EBSCO), CAB Abstracts (Thomson Reuters), PubMed, Web of Science (Thomson Reuters), BIOSIS Previews (Thomson Reuters), and ProQuest Dissertations & Theses Full Text. No restrictions on year of publication or language were placed on the search. Eligible studies assessed an intervention designed to mitigate the pain of the procedures of interest and included a comparison group that did not receive an intervention. Eligible non-English studies were translated using a translation service. Two reviewers independently screened titles and abstracts for relevance using pre-defined questions. Data were extracted from relevant articles onto pre-defined forms. From the 2203 retrieved citations forty publications, containing 52 studies met the eligibility criteria. In 40 studies, piglets underwent castration only. In seven studies, piglets underwent tail docking only. In one study, piglets underwent teeth clipping only, and in one study piglets underwent ear notching only. Three studies used multiple procedures. Thirty-two trial arms assessed general anesthesia protocols, 30 trial arms assessed local anesthetic protocols, and 28 trial arms assessed non-steroidal anti-inflammatory drugs (NSAIDs) protocols. Forty-one trial arms were controls where piglets received either placebo or no treatment. Forty-five outcomes were extracted from the studies, however only the results from studies that assessed cortisol (six studies), ß-endorphins (one study), vocalisations (nine studies), and pain-related behaviors (nine studies) are reported. Other outcomes were reported in only one or two studies. Confident decision making will likely be difficult based on this body of work because lack of comprehensive reporting precludes calculation of the magnitude of pain mitigation for most outcomes.


Subject(s)
Animal Husbandry/methods , Animal Welfare/standards , Pain Management/veterinary , Swine/physiology , Animal Husbandry/standards , Animals , Hydrocortisone/analysis , Pain Management/standards , Randomized Controlled Trials as Topic/veterinary
16.
Anim Health Res Rev ; 15(1): 39-62, 2014 Jun.
Article in English | MEDLINE | ID: mdl-25605278

ABSTRACT

Piglets reared in swine production in the USA undergo painful procedures that include castration, tail docking, teeth clipping, and identification with ear notching or tagging. These procedures are usually performed without pain mitigation. The objective of this project was to develop recommendations for pain mitigation in 1- to 28-day-old piglets undergoing these procedures. The National Pork Board funded project to develop recommendations for pain mitigation in piglets. Recommendation development followed a defined multi-step process that included an evidence summary and estimates of the efficacies of interventions. The results of a systematic review of the interventions were reported in a companion paper. This manuscript describes the recommendation development process and the final recommendations. Recommendations were developed for three interventions (CO2/O2 general anesthesia, non-steroidal anti-inflammatory drugs (NSAIDs), and lidocaine) for use during castration. The ability to make strong recommendations was limited by low-quality evidence and strong certainty about variation in stakeholder values and preferences. The panel strongly recommended against the use of a CO2/O2 general anesthesia mixture, weakly recommended for the use of NSAIDs and weakly recommended against the use of lidocaine for pain mitigation during castration of 1- to 28-day-old piglets.


Subject(s)
Animal Husbandry/methods , Pain Management/veterinary , Swine/physiology , Anesthesia, General/veterinary , Animal Husbandry/standards , Animals , Animals, Newborn , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Evidence-Based Practice , Guidelines as Topic , Lidocaine/administration & dosage , Pain Management/standards
18.
Ann R Coll Surg Engl ; 95(8): e139-41, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24165331

ABSTRACT

Spillage of gallstones during laparoscopic cholecystectomy occurs in up to 30% of cases but complications due to stone retention are less frequent. We report the first case of a hepatocolonic fistula as a consequence of a retained gallstone.


Subject(s)
Cholecystectomy, Laparoscopic/adverse effects , Colonic Diseases/etiology , Digestive System Fistula/etiology , Gallstones/complications , Liver Diseases/etiology , Gallstones/surgery , Humans , Male , Middle Aged
19.
Vet Microbiol ; 164(1-2): 108-15, 2013 May 31.
Article in English | MEDLINE | ID: mdl-23452750

ABSTRACT

The objective of this study was to evaluate if Moraxella bovoculi was associated with Infectious Bovine Keratoconjunctivitis (IBK) using a corneal scarification model in calves. A 3-arm single-eye block-randomized and blinded challenge study was designed as follows: corneal scarification only, corneal scarification and inoculation with M. bovoculi (ATCC strain: BAA-1259; origin: CA) and corneal scarification and inoculation with Moraxella bovis (strain Epp63-300; origin: NADC). The study was conducted in 3 replicates of 10-12 animals housed in individual pens with no nose-to-nose contact. Calves were enrolled after an ophthalmologist confirmed the absence of corneal, conjunctival, and eyelid abnormalities. Calves were scarified and inoculated in one randomly selected eye, then observed for the primary outcome of interest (corneal ulcers) until euthanized 10 days following scarification. Research group members assessing the outcome were blind to allocation status. The study was approved by the institutional animal care and use committee. Of 36 animals purchased for the study, 5 were excluded prior to enrollment due to ophthalmic abnormalities. Of the 31 enrolled calves, 9/10 (90%) of M. bovis calves, 0/10 (0%) of M. bovoculi calves and 1/11 (9%) of control calves developed corneal ulcerations consistent with IBK in the scarified eyes. The absence of corneal ulcerations in M. bovoculi BAA-1259 inoculated calves suggests it is not a causal organism for IBK in this model and the pathogenicity of this ATCC strain has not been established. Consistent corneal ulceration development in the M. bovis inoculated group demonstrates the ability of the model to induce IBK ulcers.


Subject(s)
Cattle Diseases/microbiology , Keratoconjunctivitis, Infectious/microbiology , Moraxellaceae Infections/veterinary , Animals , Cattle , Cornea/pathology , Female , Moraxella
20.
Water Sci Technol ; 63(11): 2692-9, 2011.
Article in English | MEDLINE | ID: mdl-22049766

ABSTRACT

While the use of environmental factors in the analysis and prediction of failures of buried reticulation pipes in cold environments has been the focus of extensive work, the same cannot be said for failures occurring on pipes in other (non-freezing) environments. A novel analysis of pipe failures in such an environment is the subject of this paper. An exploratory statistical analysis was undertaken, identifying a peak in failure rates during mid to late summer. This peak was found to correspond to a peak in the rate of circumferential failures, whilst the rate of longitudinal failures remained constant. Investigation into the effect of climate on failure rates revealed that the peak in failure rates occurs due to differential soil movement as the result of shrinkage in expansive soils.


Subject(s)
Sanitary Engineering/instrumentation , Seasons , Water Supply , Climate , Environment , Sanitary Engineering/methods , Soil , Time Factors
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