The impact of the implementation of a mobile stroke unit on a stroke cohort.

BACKGROUND: Mobile stroke units (MSUs), specialized ambulances with a built-in computed tomography (CT) scanner and telemedicine connected stroke team, have been on the rise in recent years largely due to the 'time is brain' concept. We aim to report our initial experience since establishing our MSU, the first unit in the Tri-state area, and assess its impact on the stroke standards of care timeline. METHODS: We conducted a retrospective analysis of a prospectively maintained database of all MSU dispatched cases from August 2019 to March 2020. RESULTS: Of 195 MSU responses, 101 were treated and transported by the MSU. The mean time (hr:mm) of dispatch to scene arrival was 0:07+0:03, scene arrival to CT start was 0:10+0:03, CT start to teleneuro start was 0:05+0:03, teleneuro start to scene departure was 0:06+0:05, scene departure to hospital arrival was 0:12+0:06, and hospital arrival to arterial puncture was 2:59+1:01. The mean time of dispatch to arterial puncture was 3:34+1:02. The mean teleneuro consult duration was 0:04+0:02. The mean time of last know well (LKW) to tPA administration was 1:28+0:48 with 4 (57.1 %) patients receiving tPA within 60 min of LKW and 5 (71.4 %) patients receiving tPA within 90 min. The mean time of dispatch to tPA was 0:37+0:09 and scene arrival to tPA administration was 0:28+0:07. CONCLUSION: MSUs may expedite each step along the stroke standards of care. In theory, this should drastically improve functional outcomes. However, the impact on functional outcomes or reductions in stroke-related morbidity is still unknown.

Validation of Fermentation and Processing Procedures for the Commercial-Scale Production of a Live, Attenuated Edwardsiella ictaluri Vaccine for Use in Channel Catfish Aquaculture.

Mortality associated with Edwardsiella ictaluri infection is a serious impediment to the commercial production of fingerling Channel Catfish Ictalurus punctatus. A patented, live, attenuated, orally delivered vaccine has been developed that offers exceptional protection against E. ictaluri infection in both laboratory and small-scale pond trials. Further vaccine development is contingent on the successful completion of large-scale field trials that accurately reflect industry conditions. This current work focuses on the validation of fermentation protocols and the optimization of downstream processing procedures to produce sufficient quantities of vaccine to conduct commercial-scale field trials. Eight vaccine serials were produced from a master seed stock (S97-773-340X2) in a 50-L floor model fermenter over two consecutive years. Following fermentation, cells were harvested, concentrated 10-fold, and cryogenically stored (-74°C). To assess processing protocols and determine shelf life of cryogenically stored vaccine, serials were tested for cell viability and vaccine potency at various intervals over 24 months. There were no significant differences in cell viability between the fresh vaccine and the stored frozen product. All serials provided a high level of protection (77-100% relative percent survival) against E. ictaluri infection in juvenile Channel Catfish and exhibited excellent poststorage viability. This data demonstrates that the live, attenuated, orally delivered vaccine can be stored at -74°C for at least 2 years with no reduction in cell viability or vaccine potency. Received May 17, 2016; accepted January 19, 2017.

Multiplex high resolution melting assay for estimation of Porcine Endogenous Retrovirus (PERV) relative gene dosage in pigs and detection of PERV infection in xenograft recipients.

Porcine Endogenous Retrovirus (PERV) poses an infectious risk in the field of xenotransplantation. This risk may be mitigated by breeding selectively animals bearing favorable PERV genetic characteristics including pigs with low levels of PERV integrated in the genome. A real-time quantitative polymerase chain reaction (PCR) assay employing the Roche High Resolution Melting (HRM) Master was used to estimate the relative gene dosage of PERV pol integrated within the pig genome. When assessed across 99 pigs of the Auckland Island breed numerous animals bearing low gene dosage were identified. The assay was adapted further to perform multiplex PCR for the detection of PERV infection within xenograft recipients. Besides PERV, amplification targets for the multiplex PCR include a pig cell marker for the determination of microchimerism and an internal amplification control (IAC) to assess the efficiency of nucleic acid isolation and effects of PCR inhibition. When 12 patients who had received porcine islet transplants were tested no evidence of PERV infection was found. The assay was shown to be specific, highly reproducible with superior performance over conventional nested PCR. This assay can be used as both a screening tool for PERV proviral levels within donor pigs and as a diagnostic tool to examine PERV transmission in human patients treated with porcine xenotransplantation material.

Out-of-hospital cardiac arrest-review of demographics in South Australia to inform decisions about the provision of automatic external defibrillators within the community.

INTRODUCTION: Sudden, out-of-hospital cardiac arrest (OHCA) has an annual incidence of approximately 50 per 100,000 population. Public access defibrillation is seen as one of the key strategies in the chain-of-survival for OHCA. Positioning of these devices is important for the maximization of public health outcomes. The literature strongly advocates widespread public access to automated external defibrillatiors (AEDs). The most efficient placement of AEDs within individual communities remains unclear. METHODS: A retrospective case review of OHCAs attended by the South Australia Ambulance Service in metropolitan and rural South Australia over a 30-month period was performed. Data were analyzed using Utstein-type indicators. Detailed demographics, summative data, and clinical data were recorded. RESULTS: A total of 1,305 cases of cardiac arrest were reviewed. The annual rate of OHCA was 35 per 100,000 population. Of the cases, the mean value for the ages was 66.3 years, 517 (39.6%) were transported to hospital, 761 (58.3%) were judged by the paramedic to be cardiac, and 838 (64.2%) were witnessed. Bystander cardiopulmonary resuscitation (CPR) was performed in 495 (37.9%) of cases. The rhythm on arrival was ventricular fibrillation (VF) or ventricular tachycardia (VT) in 419 (32.1%) cases, and 315 (24.1%) of all arrests had return of spontaneous circulation (ROSC) before or on arrival at the hospital. For cardiac arrest cases that were witnessed by the ambulance service (n=121), the incidence of ROSC was 47.1%. During the 30-month period, there only was one location that recorded more than one cardiac arrest. No other location recorded recurrent episodes. CONCLUSIONS: This study did not identify any specific location that would justify defibrillator placement over any other location without an existing defibrillator. The impact of bystander CPR and the relatively low rate of bystander CPR in this study points to an area of need. The relative potential impact of increasing bystander CPR rates versus investing in defibrillators in the community is worthy of further consideration.

Color and luminance increment thresholds in poor readers.

The hypotheses of a visual basis to reading disabilities in some children have centered around deficits in the visual processes displaying more transient responses to stimuli although hyperactivity in the visual processes displaying sustained responses to stimuli has also been proposed as a mechanism. In addition, there is clear evidence that colored lenses and/or colored overlays and/or colored backgrounds can influence performance in reading and/or may assist in providing comfortable vision for reading and, as a consequence, the ability to maintain reading for longer. As a consequence, it is surprising that the color vision of poor readers is relatively little studied. We assessed luminance increment thresholds and equi-luminous red-green and blue-yellow increment thresholds using a computer based test in central vision and at 10 degrees nasally employing the paradigm pioneered by King-Smith. We examined 35 poor readers (based on the Neale Analysis of Reading) and compared their performance with 35 normal readers matched for age and IQ. Poor readers produced similar luminance contrast thresholds for both foveal and peripheral presentation compared with normals. Similarly, chromatic contrast discrimination for the red/green stimuli was the same in normal and poor readers. However, poor readers had significantly lower thresholds/higher sensitivity for the blue/yellow stimuli, for both foveal and peripheral presentation, compared with normal readers. This hypersensitivity in blue-yellow discrimination may point to why colored lenses and overlays are often found to be effective in assisting many poor readers.

Genetic therapy, person-regarding reasons and the determination of identity.

It has been argued, for example by Ingmar Persson, that genetic therapy performed on a conceptus does not alter the identity of the person that develops from it, even if we are essentially persons. If this claim is true then there can be person-regarding reasons for performing genetic therapy on a conceptus. Here it is argued that such person-regarding reasons obtain only if we are not essentially persons but essentially animals. This conclusion requires the defeat of the origination theory, which says that personal identity is determined by the identity of the foetus from which one originates. It is argued that the origination theory is false in the special case relevant to performing genetic therapy on a conceptus for person-regarding reasons.

Identity and the ethics of gene therapy.

Some conditions detrimental to human well-being, such as sickle-cell anaemia, cystic fibrosis, muscular dystrophy, Lesch-Nyhan disease and various immunodeficiencies, are genetically determined. One potential means of preventing the development of such conditions is the manipulation of genetic material in the conceptus of an organism which would otherwise develop such conditions. Genetic manipulations could take the form either of excising and substituting genetic material, excising but not substituting genetic material, adding but not excising genetic material or reorganizing existing genetic material. To succeed, manipulation would have to change genetic structure so as to change its informational content. It might be thought, however, that all or some such manipulations would involve causing particular individuals to cease to exist and involve bringing into existence new, distinct individuals. Gene therapy could not, therefore, be a procedure which improved the circumstances of the particular individual to whom it is applied. It might be suggested that once the metaphysics of identity and the facts of gene therapy are understood, certain interesting conclusions concerning the ethics of gene therapy emerge. Some such conclusions have been discussed in this journal by Noam J. Zohar and Jeffrey P. Kahn. More, however, needs to be said about them since neither Zohar nor Kahn draws the correct conclusions. While both have pertinent things to say, neither has given a completely clear account of the metaphysics of gene therapy and so neither has completely traced out the implication of the metaphysics for the ethics of gene therapy. This paper attempts to remedy these defects.