Short-term risk prediction after major lower limb amputation: PERCEIVE study

BACKGROUND

The accuracy with which healthcare professionals (HCPs) and risk prediction tools predict outcomes after major lower limb amputation (MLLA) is uncertain. The aim of this study was to evaluate the accuracy of predicting short-term (30 days after MLLA) mortality, morbidity, and revisional surgery.

METHODS

The PERCEIVE (PrEdiction of Risk and Communication of outcomE following major lower limb amputation: a collaboratIVE) study was launched on 1 October 2020. It was an international multicentre study, including adults undergoing MLLA for complications of peripheral arterial disease and/or diabetes. Preoperative predictions of 30-day mortality, morbidity, and MLLA revision by surgeons and anaesthetists were recorded. Probabilities from relevant risk prediction tools were calculated. Evaluation of accuracy included measures of discrimination, calibration, and overall performance.

RESULTS

Some 537 patients were included. HCPs had acceptable discrimination in predicting mortality (931 predictions; C-statistic 0.758) and MLLA revision (565 predictions; C-statistic 0.756), but were poor at predicting morbidity (980 predictions; C-statistic 0.616). They overpredicted the risk of all outcomes. All except three risk prediction tools had worse discrimination than HCPs for predicting mortality (C-statistics 0.789, 0.774, and 0.773); two of these significantly overestimated the risk compared with HCPs. SORT version 2 (the only tool incorporating HCP predictions) demonstrated better calibration and overall performance (Brier score 0.082) than HCPs. Tools predicting morbidity and MLLA revision had poor discrimination (C-statistics 0.520 and 0.679).

CONCLUSION

Clinicians predicted mortality and MLLA revision well, but predicted morbidity poorly. They overestimated the risk of mortality, morbidity, and MLLA revision. Most short-term risk prediction tools had poorer discrimination or calibration than HCPs. The best method of predicting mortality was a statistical tool that incorporated HCP estimation.

OA foundations - experimental models of osteoarthritis

Osteoarthritis (OA) is increasingly recognised as a disease of diverse phenotypes with variable clinical presentation, progression, and response to therapeutic intervention. This same diversity is readily apparent in the many animal models of OA. However, model selection, study design, and interpretation of resultant findings, are not routinely done in the context of the target human (or veterinary) patient OA sub-population or phenotype. This review discusses the selection and use of animal models of OA in discovery and therapeutic-development research. Beyond evaluation of the different animal models on offer, this review suggests focussing the approach to OA-animal model selection on study objective(s), alignment of available models with OA-patient sub-types, and the resources available to achieve valid and translatable results. How this approach impacts model selection is discussed and an experimental design checklist for selecting the optimal model(s) is proposed. This approach should act as a guide to new researchers and a reminder to those already in the field, as to issues that need to be considered before embarking on in vivo pre-clinical research. The ultimate purpose of using an OA animal model is to provide the best possible evidence if, how, when and where a molecule, pathway, cell or process is important in clinical disease. By definition this requires both model and study outcomes to align with and be predictive of outcomes in patients. Keeping this at the forefront of research using pre-clinical OA models, will go a long way to improving the quality of evidence and its translational value.

Efficacy of high-intensity interval training on cardiac autonomic modulation in cardiovascular diseases and lifestyle disorders: a systematic review and meta-analysis

The study aims to investigate the literature on the effect of high-intensity interval training (HIIT) on cardiac autonomic function in individuals with cardiovascular disease (CVD) and lifestyle disorders. We performed electronic database search from CENTRAL, WoS, Scopus, Pubmed, and PEDro up to 25th February 2021. Randomised control trials/quasi-experimental trials/cross-over trials that assessed the effects of HIIT with control/alternative treatment on cardiac autonomic control were included in this review. A total of 11 studies were included for qualitative analysis and among them, 8 were quantitatively analysed. A random-effect model of standardised mean difference (SMD) and mean difference of the respective outcome measures for cardiac autonomic control was determined. The findings of the qualitative analysis revealed the beneficial effects of HIIT on cardiac autonomic modulation. However, the majority of the studies had an unclear or high risk of bias for randomisation, concealment methods, and blinding of participants to the intervention that could have influenced the interpretation of the findings. The SMD revealed a significant effect of HIIT on standard deviation of N-N intervals (SDNN) (ms) [SMD: 0.40, 95% confidence interval (CI): -0.001 to 0.80, P=0.05], high frequency power (HF) (ms2) [0.46, 95% CI: 0.17 to 0.76, P=0.002], and ratio of low and high frequency power, (LF/HF) [-0.80, 95% CI: -1.27 to -0.33, P=0.0008]. In conclusion, HIIT may effectively modulate cardiac autonomic function by increasing parasympathetic dominance, sympathetic withdrawal, and sympathovagal balance in individuals with CVD and lifestyle disorders. The study has a PROSPERO registration number: CRD42021231225

Pathology-pain relationships in different osteoarthritis animal model phenotypes: it matters what you measure, when you measure, and how you got there

OBJECTIVE

To determine whether osteoarthritis (OA) pain characteristics and mechanistic pathways in pre-clinical models are phenotype-specific.

DESIGN

Male 11-week-old C57BL6 mice had unilateral medial-meniscal-destabilization (DMM) or antigen-induced-arthritis (AIA), vs sham-surgery/immunised-controls (Sham/Im-CT). Pain behaviour (allodynia, mechanical- and thermal-hyperalgesia, hindlimb static weight-bearing, stride-length) and lumbar dorsal root ganglia (DRG) gene-expression were measured at baseline, day-3, week-1/-2/-4/-8/-16, and pain-behaviour:gene-expression:joint-pathology associations investigated.

RESULTS

DMM and AIA induced structural OA defined by progressively increasing cartilage erosion, subchondral bone sclerosis and osteophyte size and maturation. All pain-behaviours were modified, with model-specific differences in severity and temporal pattern. Tactile allodynia developed acutely in both models and persisted to week-16. During early-OA (wk4-8) there was; reduced right hindlimb weight-bearing in AIA; thermal-hyperalgesia and reduced stride-length in DMM. During chronic-OA (wk12-16); mechanical-hyperalgesia and reduced right hindlimb weight-bearing were observed in DMM only. There were no associations in either model between different pain-behaviour outcomes. A coordinated DRG-expression profile was observed in sham and Im-CT for all 11 genes tested, but not in AIA and DMM. At wk-16 despite equivalent joint pathology, changes in DRG-expression (Calca, Trpa1, Trpv1, Trpv4) were observed only in DMM. In AIA mechanical-hyperalgesia was associated with Trpv1 (r = -0.79) and Il1b (r = 0.53). In DMM stride-length was associated with Calca, Tac1, Trpv1, Trpv2, Trpv4 and Adamts5 (r = 0.4-0.57). DRG gene-expression change was correlated with subchondral-bone sclerosis in DMM, and cartilage damage in AIA. Positive pain-behaviour:joint-pathology associations were only present in AIA - for synovitis, subchondral-bone resorption, chondrocyte-hypertrophy and cartilage damage.

CONCLUSION

Pain and peripheral sensory neuronal responses are OA-phenotype-specific with distinct pathology:pain-outcome:molecular-mechanism relationships.

Enhancing the impedance matched bandwidth of bottle microresonator signal processing devices

Light pulses entering an elongated bottle microresonator (BMR) from a transversely oriented input-output waveguide (microfiber) slowly propagate along the BMR length and bounce between turning points at its constricting edges. To avoid insertion losses and processing errors, a pulse should completely transfer from the waveguide into the BMR and, after being processed, completely return back into the waveguide. For this purpose, the waveguide and BMR should be impedance matched along the pulse bandwidth. Here we show how to enhance the impedance matched bandwidth by optimization of the BMR effective radius variation in a small vicinity of the input-output waveguide.

948 Visceral Artery Aneurysms- A Single Centre Experience Over 6 Years

Introduction

The incidence of visceral artery aneurysms (VAA) varies from 0.01-0.1%. They are significant with a mortality risk of up to 75% if ruptured. Given there are no national guidelines we decided to conduct this study to assess the management of VAA in our trust and recommend local guidelines.

Method

We retrospectively identified patients who had a detected VAA between April 2014 and April 2020. Medical records and relevant imaging were reviewed in detail. MDT outcomes and subsequent mortalities noted.

Results

We identified 62 VAA in 59 patients (23 male), median age 65 years, and mean diameter 18.1 mm. 95 % were detected on CT, the indication was mostly malignancy. MDT outcomes were to continue surveillance for 43 patients with yearly scans, 5 patients had primary surgical repair, 7 patients had endovascular interventions, 1 patient had primary endovascular intervention that failed and required surgical intervention. 7 patients were discharged from follow up due to age and size (12 mm) or VAA completely thrombosed.

Conclusions

In our unit decisions to intervene were based on size > 20mm, rapid increase in size on surveillance, the presence of portal hypertension or possibly the patients’ young age. There were no mortalities linked to VAA.

942 Cost Effectiveness of Percutaneous EVARs Compared to Standard Cut Down

Introduction

Percutaneous EVAR (PEVAR) is gaining popularity worldwide. Our aim is to identify whether PEVAR is cost effective compared to open access.

Method

We retrospectively identified patients undergoing EVAR for unruptured AAA over a 4-year period (April 2014- December 2018). Demographic, procedural, and financial data were collected. Exclusion criteria were complex EVARs and EVARs with planned adjunct procedures. Outcome measures were length of stay (LOS), number of Perclose devices used, number of failures, need for adjuncts, theatre time used, and total cost of each.

Results

318 patients (88.4% male) underwent EVAR between January 2015 and October 2018, average age 76.9 years and median maximal aortic diameter 60mm. 61 EVARs were planned for open access, and a sample of the latest 92 consecutive PEVARs were selected to prevent bias. The median LOS following PEVAR was 1 day less (2 vs 3 days). Mean Proglides used were 5. 2.7% of devices failed, and no surgical cut-down was required in this cohort. Mean theatre time used for PEVAR was 179 minutes vs 213 minutes for open access. All considered, PEVARs cost £124 less.

Conclusions

PEVAR is associated with a shorter length of hospital stay and is more cost effective than open access.

598 Patients’ Knowledge and Compliance with Government Guidelines for COVID 19

Background

Since the outbreak of COVID-19; social distancing and recognized effective precautions were recommended by various governments to fight the viral spread.

Our aim was to assess the inpatient knowledge and compliance with the government guidelines during their hospital stay and at their discharge in two different NHS hospitals.

Method

The study took place in two hospitals: Berrywood hospital, UK and Countess of Chester hospital, UK. We invited inpatients to answer an anonymized questionnaire which was designed to include the contemporary government guidelines. We excluded patients with cognitive impairment and those who were not expected to be discharged within days.

Results

Out of 209 patients, 50% were male. Patients showed good awareness of the main symptoms of the virus (90%). However, A significant number of patients were not fully aware of the recommended precautions to minimize viral spread (28%) and the method of spread (43%). About 41% did not know the recommended safe distance.

Conclusions

Despite being aware of the main symptoms of COVID-19, a significant number of patients lack essential information needed to minimize the spread of the virus in the society and hospital. We recommend providing patients with information leaflets and direct advice on admission and discharge.

Microresonator devices lithographically introduced at the optical fiber surface

We present a simple lithographic method for fabrication of microresonator devices at the optical fiber surface. First, we undress the predetermined surface areas of a fiber segment from the polymer coating with a focused CO₂ laser beam. Next, using the remaining coating as a mask, we etch the fiber in a hydrofluoric acid solution. Finally, we completely undress the fiber segment from coating to create a chain of silica bottle microresonators with nanoscale radius variation [surface nanoscale axial photonics (SNAP) microresonators]. We demonstrate the developed method by fabrication of a chain of five 1 mm long and 30 nm high microresonators at the surface of a 125 µm diameter optical fiber and a single 0.5 mm long and 291 nm high microresonator at the surface of a 38 µm diameter fiber. As another application, we fabricate a rectangular 5 mm long SNAP microresonator at the surface of a 38 µm diameter fiber and investigate its performance as a miniature delay line. The propagation of a 100 ps pulse with 1 ns delay, 0.035c velocity, and negligible dispersion is demonstrated. In contrast to previously developed approaches in SNAP technology, the developed method allows the introduction of much larger fiber radius variation ranging from nanoscale to microscale.

Role of topical oxytocin in improving vaginal atrophy in postmenopausal women: a randomized, controlled trial

OBJECTIVE AND DESIGN

Prospective randomized controlled trial to test the effectiveness of topical oxytocin gel to improve vaginal atrophy in postmenopausal women.

PATIENTS AND METHODS

A total of 140 postmenopausal women presenting with vaginal atrophy and who satisfied the inclusion and exclusion criteria were randomized into two groups each of 70 patients; they received intravaginal oxytocin gel or placebo gel for 30 days. Serum estrogen level, visual, colposcopic and histological vaginal examination were performed before and after treatment.

RESULTS

Forty-seven out of 70 women in the oxytocin gel group improved after treatment and none in the placebo group (p = 0.001). Forty-five participants in the oxytocin group and seven in the placebo group reported relief of dyspareunia (p = 0.001). Thirty-four participants in the oxytocin group and seven in the placebo group reported relief of soreness (p = 0.001). There was no significant difference between the circulating levels of estradiol in both groups before and after treatment (p = 0.4 and 0.6 for the oxytocin group and the placebo group, respectively).

CONCLUSION

Oxytocin gel is useful in the restoration of the vaginal epithelium in cases of postmenopausal atrophic vaginitis. Further studies with a longer follow-up period are required to test the long-term effects of oxytocin as a treatment for vaginal atrophy.

What constitutes an "animal model of osteoarthritis"--the need for consensus?

OBJECTIVE

To review the use of animal models of osteoarthritis (OA) with regard to their utility for investigation of the mechanisms and regulation of structural pathology and pain.

METHODS

PubMed searches were conducted using separate clusters of terms to retrieve articles on (i) models of structural joint damage in genetically-modified (GM) mice, and (ii) models of OA joint pain. The papers were reviewed to investigate whether there was evidence that the research outcome was dependent on the model used.

RESULTS

Out of a total of 109 separate GM mice strains identified in which an effect on OA was reported, 15 had been studied using more than one arthritis model. In 10/15 the same effect of the GM on arthritis was reported in at least two different models. In 5/15 the effect of the GM on arthritis structural pathology was different, and sometimes opposite, when comparing two or more induction methods. A total of 112 publications were retrieved in which pain/disability was examined in a model suggested to represent OA. The induction methods used most commonly to study "OA pain" were distinct from those most often used to investigate the pathophysiology and regulation of structural joint damage. Four papers directly comparing pain mechanisms in different models were identified, with 3/4 describing differences in nociceptive pathways.

CONCLUSIONS

The available data indicates that the molecular mechanisms of both joint structural damage and pain may be distinct in animal models of OA induced or initiated by different means. This suggests the need to continue using multiple OA animal models but that the subsequent interpretation of the data and its extrapolation to the human condition must be more precise.

Pneumonia due to Mycobacterium abscessus in two domestic ferrets (Mustelo putorius furo)

Two ferrets were diagnosed with pneumonia due to Mycobacterium abscessus. Both cases were treated successfully using clarithromycin after positive cultures were obtained via unguided bronchoalveolar lavage. This is the first time M abscessus has been isolated in our laboratory and the first report of this organism causing disease in companion animals in Australia. Underlying respiratory tract disease was thought to be an important factor in the development of the infections. Thorough investigation of chronic lower respiratory tract disease in ferrets is recommended as this species appears predisposed to atypical infections.

Evaluation of four warming procedures to minimise heat loss induced by anaesthesia and surgery in dogs

OBJECTIVE

To evaluate the efficiency of four warming procedures, introduced after anaesthetic induction and continued during surgery, in minimising heat loss in anaesthetised dogs.

DESIGN

Dogs were paired. One of each pair was a control; the other was subjected to one of four warming procedures.

METHODS

Ninety-six dogs were involved in total. Pairs of dogs were matched for breed, hair length, and type of surgical procedure and placed adjacent to each other in a large temperature-controlled surgical theatre. One dog within each pair was assigned to one of four warming procedures that commenced immediately after anaesthetic induction. Group 1 (11 pairs) were placed on a purpose-designed prewarmed (41 degrees C) electrically heated pad. Group 2 (18 pairs) were placed on a prewarmed electric heat pad (41 degrees C), cocooned by four wrapped water bottles (initially 41 degrees C) and subjected to radiant heat (150 watt lamp placed 50 cm away from the head of the dog). Group 3 (11 pairs) were surrounded by a forced air warming mattress (set at 43 degrees C). Group 4 (8 pairs) were connected via the anaesthetic breathing circuit to a heater/humidifier (set at 41 degrees C). Rectal temperature measurements were recorded every 15 min for the first 3 h of anaesthesia. The fall in rectal temperature of the control dog was subtracted from the fall in temperature of the treatment dog and this measurement was used to assess the efficacy of the various warming procedures.

RESULTS

The mean rectal temperature of unheated 'control' dogs decreased 1.9 +/- 0.6, 1.4 +/- 0.4 and 1.1 +/- 0.4 degrees C over the first, second and third hour respectively. After 3 h the temperature fall differential for all groups were 0.7 +/- 0.7 (Group 1), 3.1 +/- 1.1 (Group 2), 2.4 +/- 1.1 (Group 3) and 1.0 +/- 1.1 degrees C (Group 4). Thus the group 2 procedure was the most successful in preventing a drop of temperature followed by groups 3, 4 and 1.

CONCLUSION

Large dogs undergo significant reduction in core body temperature especially during the first 2 h of anaesthesia and surgery. Supplementary warming substantially reduces this fall in body temperature, although certain warming procedures were found to be more effective than others.

Long-term outcomes of acute myeloid leukemia in adults in Pakistan

OBJECTIVE

To describe the long-term outcomes of Acute Myeloid Leukemia (AML) and to study clinicopathological features at presentation, morphological subtypes and remission rates.

METHODS

Demographic information, response to therapy and survival of patients (>14 years of age) admitted between January 1988 to August 1996 with acute myeloid leukaemia was retrieved and analysed.

RESULTS

Seventy-four patients were admitted with a diagnosis of AML during the study period. There were 43 males and 31 females. Age ranged between 15 and 70 years with a mean age of 38 years. The most common presenting feature was fever (67.5%) and the morphological subtype according to French-American-British Group (FAB) criteria was M4. Fifty-five patients received treatment and were evaluable for response and outcomes. Thirty-six (65.4%) patients had complete remission. Sixteen (29.1%) died during the first 28 days after starting induction chemotherapy. The median survival was 11 months. Six (11%) patients (4 females, 2 males) are surviving beyond 4 years (long-term survivors).

CONCLUSION

Our study suggests that the long-term outcomes of adults with AML are comparable to what has been reported in the literature for patients who do not receive bone marrow transplants.

Acute myeloid leukemia in children in Pakistan: an audit

OBJECTIVE

To see the clinical features and treatment of children with Acute Myeloid Leukemia (AML) in Pakistan.

SETTING

Tertiary referral at a specialist Hematology/Oncology center.

METHODS

Retrospective, chart-based review of children (less than 14 years) admitted to the hospital with a diagnosis of AML between January 1987 and August 1997.

RESULTS

A total of 23 patients were admitted. There were 18 males and 5 females. The mean age was 8 +/- 5 years. M3 was the commonest morphological subtype (43%). Twenty-two percent of the patients presented with hyperleucocytosis (TLC > 100 x 10(9)/L) and 95% with an elevated LDH (> 548 IU/L). Pneumonia at presentation was seen in 29%. Of 23 patients 14 were evaluable for responses. Six patients died early (43%); 3 before starting the chemotherapy and 3 during the induction chemotherapy, 8/11 (73%) patients entered remission. The median survival was 9 months.

CONCLUSION

The pediatric patients with acute myeloid leukemia present with advanced disease. There is a high early death rate (within 28 days of diagnosis). The long-term outcome was inferior to that reported in the literature.

Hepatic cysts incarcerated in a peritoneopericardial diaphragmatic hernia

Peritoneopericardial diaphragmatic hernia is a common incidental finding in cats and is rarely symptomatic. The case report described herein presented with dyspnoea secondary to incarceration of hepatic cysts within the pericardial space of a cat with a peritoneopericardial diaphragmatic hernia.

Molecular characterization of phenol-degrading bacteria isolated from different Egyptian ecosystems

Twelve selected phenol-degrading bacterial isolates were obtained on phenol agar plates using culture enrichment technique. Molecular identification of the isolates was performed using eubacterial 16S rRNA PCR specific primers. Based on 16S rDNA sequence analysis, the results revealed that the majority of the isolates (8 out of 12) are affiliated to the g-subdivision of Proteobacteria. Four out of the eight isolates are closely related to the genus Acinetobacter. Molecular heterogeneity among the phenol-degrading isolates was further investigated by using rep-PCR chromosomal fingerprinting and correlated with plasmid and antibiotic profile analysis. Rep-PCR results strongly confirmed that the bacterial isolates from different environmental sites produced different fingerprinting patterns. The mineralization of phenol by all isolates was evaluated using 14C-labeled phenol assay. Phenol mineralization ranged from 55% (W-17) to 0.4% (Sea-9). This was further confirmed by the detection of several monoaromatic and polyaromatic degrading genes, e.g., pheA, MopR, XylE, and NahA. In addition, catalytic enzymes such as catalase and dioxygenase were also monitored.

Comparative pathology of the diseases caused by Hendra and Nipah viruses

Information on the pathogenesis and transmissibility of Hendra and Nipah viruses was obtained by comparing their histopathology. Both viruses induced syncytial cells in vascular tissues and they were primarily vasotropic and/or neurotropic, generating interstitial pneumonia or encephalitis. Nipah virus in pigs was also epitheliotropic in respiratory epithelium and thus contagious.

Bioterrorism-related inhalational anthrax: the first 10 cases reported in the United States

From October 4 to November 2, 2001, the first 10 confirmed cases of inhalational anthrax caused by intentional release of Bacillus anthracis were identified in the United States. Epidemiologic investigation indicated that the outbreak, in the District of Columbia, Florida, New Jersey, and New York, resulted from intentional delivery of B. anthracis spores through mailed letters or packages. We describe the clinical presentation and course of these cases of bioterrorism-related inhalational anthrax. The median age of patients was 56 years (range 43 to 73 years), 70% were male, and except for one, all were known or believed to have processed, handled, or received letters containing B. anthracis spores. The median incubation period from the time of exposure to onset of symptoms, when known (n=6), was 4 days (range 4 to 6 days). Symptoms at initial presentation included fever or chills (n=10), sweats (n=7), fatigue or malaise (n=10), minimal or nonproductive cough (n=9), dyspnea (n=8), and nausea or vomiting (n=9). The median white blood cell count was 9.8 X 10(3)/mm(3) (range 7.5 to 13.3), often with increased neutrophils and band forms. Nine patients had elevated serum transaminase levels, and six were hypoxic. All 10 patients had abnormal chest X-rays; abnormalities included infiltrates (n=7), pleural effusion (n=8), and mediastinal widening (seven patients). Computed tomography of the chest was performed on eight patients, and mediastinal lymphadenopathy was present in seven. With multidrug antibiotic regimens and supportive care, survival of patients (60%) was markedly higher (<15%) than previously reported.

Acute encephalomyelitis during an outbreak of enterovirus type 71 infection in Taiwan: report of an autopsy case with pathologic, immunofluorescence, and molecular studies

We report a fatal case of enterovirus type 71 (EV 71) infection in an 8-year-old girl during a summer outbreak of hand, foot, and mouth disease in 1998 in Taiwan. The clinical course was rapidly progressive, with manifestations of hand, foot, and mouth disease, aseptic meningitis, encephalomyelitis, and pulmonary edema. The patient died 24 hours after admission. Postmortem study revealed extensive inflammation in the meninges and central nervous system and marked pulmonary edema with focal hemorrhage. Brain stem and spinal cord were most severely involved. The inflammatory infiltrates consisted largely of neutrophils involving primarily the gray matter with perivascular lymphocytic cuffing, and neuronophagia. The lungs and heart showed no evidence of inflammation. EV 71 was isolated from the fresh brain tissues and identified by immunofluorescence method with type-specific EV 71 monoclonal antibody. It was also confirmed by neutralization test and reverse-transcriptase polymerase chain reaction with sequence analysis. The present case was the first example in which EV 71 was demonstrated to be the causative agent of fatal encephalomyelitis during its epidemic in Taiwan.

Pathogenicity of West Nile virus for turkeys

In the fall of 1999, West Nile virus (WNV) was isolated during an outbreak of neurologic disease in humans, horses, and wild and zoological birds in New York, Connecticut, and New Jersey. Turkeys could potentially be a large reservoir for WNV because of the high-density turkey farming and the presence of large wild turkey populations in the eastern seaboard of the United States. Little is known about the pathogenicity of WNV in domestic or wild turkeys. Specific-pathogen-free 3-wk-old turkeys were inoculated subcutaneously with 10(3.3) mean tissue culture infective doses of a WNV strain isolated fromthe index case in a New York crow. No clinical signs were observed in the turkeys over the 21 days of the experiment. One turkey died abruptly at 8 days postinoculation (DPI). Many turkeys developed viremia between 2 and 10 DPI, but the average level of virus was very low, less than needed to efficiently infect mosquitos. Low levels of WNV were detected in feces on 4 and 7 DPI, but no virus was isolated from oropharyngeal swabs. WNV wasnot transmitted from WNV-inoculated to contact-exposed turkeys. All WNV-inoculated poults seroconverted on 7 DPI. In the turkey that died, WNV was not isolated from intestine, myocardium, brain, kidney, or cloacal and oropharyngeal swabs, but sparse viral antigen was demonstrated by immunohistochemistry in the heart and spleen. Turkeys in contact with WNV-inoculated turkeys and sham-inoculated controls lacked WNV specific antibodies,and WNV was not isolated from plasma and cloacal and oropharyngeal swabs. These data suggest that WNV lacks the potential to be a major new disease of turkeys and that turkeys will not be a significant amplifying host for infecting mosquitos.

Coronary revascularization of the circumflex system: different approaches and long-term outcome

BACKGROUND

Minimally invasive direct coronary artery bypass, without cardiopulmonary bypass, through a left lateral thoracotomy approach (lateral MIDCAB), is a safe alternative to coronary artery bypass surgery using cardiopulmonary bypass (on-pump CABG) of the circumflex system via median sternotomy. However, it is unknown whether lateral MIDCAB may yield an improved long-term outcome over the conventional on-pump median sternotomy approach.

METHODS

We compared the perioperative outcomes of patients undergoing lateral MIDCAB (n = 34) versus conventional on-pump CABG of the circumflex system (n = 16) from June 1996 to July 1999. The two groups were similar with respect to baseline characteristics and risk stratification. Patients who required only one or two grafts for complete revascularization were included.

RESULTS

Lateral MIDCAB patients had a lower need than on-pump CABG patients for intraoperative (12% MIDCAB vs 43% on-pump CABG, p = 0.03) and postoperative transfusions (29% vs 69%, p = 0.01), had fewer neuropsychologic changes (0% vs 19%, p = 0.03), and had a lower rate of postoperative atrial fibrillation (12% vs 44%, p = 0.02). Lateral MIDCAB was also associated with a significantly lower postoperative length of stay (5 +/- 2 vs 7 +/- 3 days, p = 0.02). Actuarial survival at a mean period of follow-up of 19 +/- 11 months was 97% for the lateral MIDCAB versus 88% for the on-pump CABG group (p = 0.6). Event-free survival was 88% for lateral MIDCAB versus 81% for on-pump CABG (p = 0.1).

CONCLUSIONS

Lateral MIDCAB may safely be performed in patients with isolated coronary artery disease of the circumflex system with improved early morbidity and an abbreviated hospital stay compared with conventional median sternotomy on-pump CABG.

An outbreak of plague including cases with probable pneumonic infection, Ecuador, 1998

During February and March of 1998, 12 sudden deaths were reported among residents of a high-Andean community in Ecuador. All 12 fatalities were members of the same extended family and some had apparent exposure to sick guinea-pigs. Following an initial investigation by public health officials, an additional death was reported in a nearby community in April, also associated with exposure to sick guinea-pigs. Blood samples from humans, dogs, and a rodent were tested for antibody to the F1 antigen of Yersinia pestis by passive haemagglutination assay. Tissue from rodents was subjected to direct fluorescent antibody staining using fluorescein-labelled monoclonal antibody to Y. pestis F1 antigen. Formalin-fixed specimens from the 2 autopsies were evaluated using a 2-step alkaline phosphatase immunoassay with a monoclonal antibody to Y. pestis F1 antigen, and tissues that had not been embedded in paraffin were tested for the presence of DNA encoding the F1 structural antigen by polymerase chain reaction. Serological evaluation of close contacts of the fatalities revealed positive titres to F1 antigen of Y. pestis, the aetiological agent of plague, in 3 contacts from the first community and 1 from the second. Immunohistochemical staining of tissues collected from 2 of the fatalities provided evidence that both had pneumonic plague. Five of 14 dogs found in the communities were seropositive for plague antibody, providing evidence of a recent epizootic plague in the area.

The use of sevoflurane in a 2:1 mixture of nitrous oxide and oxygen for rapid mask induction of anaesthesia in the cat

An inhalational technique for rapid induction of anaesthesia in unsedated cats using sevoflurane and nitrous oxide is described. Using a pliable, tight-fitting, face mask, sevoflurane (7.5-8%) was delivered from an out-of-circuit precision vaporiser connected to a coaxial non-rebreathing system using a fresh gas flow of 1 l oxygen and 2 l nitrous oxide per min. Cats were restrained with gentle but firm pressure applied by scruffing the dorsal cervical skin until the righting reflex was lost and the patient could be positioned in lateral recumbency. Typically, cats could be positioned on their side in a light plane of anaesthesia within 1 min of applying the mask, at which time the sevoflurane concentration was reduced to 5% or less. A similar protocol, using a lower initial concentration of sevoflurane, is recommended for old or debilitated patients. Maintenance of light sevoflurane (2-4%) anaesthesia by mask permitted minor interventions to be performed readily, including blood collection, intravenous chemotherapy, abdominal palpation, radiography and ultrasonography. More painful procedures, such as bone marrow aspiration, required a deeper plane of anaesthesia. Cats were sufficiently deep to be intubated, if this was required, about 3 min after commencing the induction. Recovery from sevoflurane/nitrous oxide anaesthesia was smooth and rapid, with most cats being able to right within 5 min of discontinuing the agents. This protocol for rapid inhalational induction and recovery is particularly suited to feline practice, where rendering an uncooperative patient unconscious greatly facilitates the completion of many minor diagnostic and therapeutic procedures, especially when these must be performed on successive days or when peripheral vascular access is limited. For longer procedures, isoflurane may be substituted for sevoflurane for maintenance of anaesthesia in order to minimise cost.

Transmission of Black Creek Canal virus between cotton rats

Black Creek Canal (BCC) virus is a hantavirus associated with hantavirus pulmonary syndrome in southeastern North America. The virus was isolated from the spleen of a cotton rat (Sigmodon hispidus) trapped in southern Florida. Our previous studies have shown that we could consistently infect male cotton rats with BCC virus in the laboratory. These animals became persistently infected and virus could be detected in salivary glands, urine, and feces. In this report we show: (1) female and male cotton rats are equally susceptible to BCC virus infection, (2) susceptibility to infection was not influenced by age, (3) all inoculated rats transmitted the infection to uninoculated cage mates, and (4) offspring of infected rats became infected despite the presence of high maternal antibodies. The course of BCC virus infection, as determined by antibody response and the ability to isolate or detect virus, appeared to be similar regardless of whether the rats obtained their infection by inoculation or contact with inoculated rats. J. Med. Virol. 60:70-76, 2000. Published 2000 Wiley-Liss, Inc.

Testing umbilical cords for funisitis due to Treponema pallidum infection, Bolivia

To establish the frequency of necrotizing funisitis in congenital syphilis, we conducted a prospective descriptive study of maternal syphilis in Bolivia by testing 1,559 women at delivery with rapid plasma reagin (RPR). We examined umbilical cords of 66 infants whose mothers had positive RPR and fluorescent treponemal antibody absorption tests. Histologic abnormalities were detected in 28 (42%) umbilical cords (seven [11%] had necrotizing funisitis with spirochetes; three [4%] had marked funisitis without necrosis; and 18 [27%] had mild funisitis), and 38 [58%] were normal. Of 22 umbilical cords of infants from mothers without syphilis (controls), only two (9%) showed mild funisitis; the others were normal. Testing umbilical cords by using immunohistochemistry is a research tool that can establish the frequency of funisitis due to Treponema pallidum infection.

Surgical removal of an ependymoma from the third ventricle of a cat

A 10-year-old spayed domestic shorthaired cat was presented for behavioural changes, signs suggestive of visual deficits and aimless circling. Neuro-ophthalmological examination suggested the cat had central blindness. CT scans following administration of iohexol demonstrated a contrast-enhancing mass in the vicinity of the third ventricle resulting in obstructive hydrocephalus. Following rostral tentorial craniotomy and incision through the cerebral cortex, the third ventricle was approached via the dilated left lateral ventricle. An ependymoma was seen through a dorsocaudolateral incision into the third ventricle, and removed by gentle manipulation and suction. The cat recovered unremarkably, regaining normal vision and behaviour.