To evaluate seasonal trivalent inactivated influenza vaccine effectiveness (VE) in Scotland, we performed a Scotland-wide linkage of patient-level primary care, hospital and virological swab data from 3,323 swabs (pooling data over nine influenza seasons: 2000/01 to 2008/09). We estimated the VE for reducing real-time RT-PCR-confirmed influenza using a test-negative study design. Vaccination was associated with a 57% (95% confidence interval (CI): 31–73) reduction in the risk of PCR-confirmed influenza. VE was 60% (95% CI: 22–79) for patients younger than 65 years and clinically at risk of serious complications from influenza, and 19% (95% CI: −104 to 68) for any individual 65 years and older. Vaccination was associated with substantial, sustained reductions in laboratory-confirmed influenza in the general population and younger patients in clinical at-risk groups

Accurate identification of ischemic penumbra will improve stroke patient selection for reperfusion therapies and clinical trials. Current magnetic resonance imaging (MRI) techniques have limitations and lack validation. Oxygen challenge T*2 MRI (T*2 OC) uses oxygen as a biotracer to detect tissue metabolism, with penumbra displaying the greatest T*2 signal change during OC. [14C]2-deoxyglucose (2-DG) autoradiography was combined with T*2 OC to determine metabolic status of T*2-defined penumbra. Permanent middle cerebral artery occlusion was induced in anesthetized male Sprague-Dawley rats ( n = 6). Ischemic injury and perfusion deficit were determined by diffusion- and perfusion-weighted imaging, respectively. At 147 ± 32 minutes after stroke, T*2 signal change was measured during a 5-minute 100% OC, immediately followed by 125 μCi/kg 2-DG, intravenously. Magnetic resonance images were coregistered with the corresponding autoradiograms. Regions of interest were located within ischemic core, T*2-defined penumbra, equivalent contralateral structures, and a region of hyperglycolysis. A T*2 signal increase of 9.22% ± 3.9% (mean ± s.d.) was recorded in presumed penumbra, which displayed local cerebral glucose utilization values equivalent to contralateral cortex. T*2 signal change was negligible in ischemic core, 3.2% ± 0.78% in contralateral regions, and 1.41% ± 0.62% in hyperglycolytic tissue, located outside OC-defined penumbra and within the diffusion abnormality. The results support the utility of OC-MRI to detect viable penumbral tissue following stroke.

Magnetic resonance imaging (MRI) with oxygen challenge (T*2 OC) uses oxygen as a metabolic biotracer to define penumbral tissue based on CMRO2 and oxygen extraction fraction. Penumbra displays a greater T*2 signal change during OC than surrounding tissue. Since timely restoration of cerebral blood flow (CBF) should salvage penumbra, T*2 OC was tested by examining the consequences of reperfusion on T*2 OC-defined penumbra. Transient ischemia (109 ± 20 minutes) was induced in male Sprague-Dawley rats ( n = 8). Penumbra was identified on T*2-weighted MRI during OC. Ischemia and ischemic injury were identified on CBF and apparent diffusion coefficient maps, respectively. Reperfusion was induced and scans repeated. T2 for final infarct and T*2 OC were run on day 7. T*2 signal increase to OC was 3.4% in contralateral cortex and caudate nucleus and was unaffected by reperfusion. In OC-defined penumbra, T*2 signal increased by 8.4% ± 4.1% during ischemia and returned to 3.25% ± 0.8% following reperfusion. Ischemic core T*2 signal increase was 0.39% ± 0.47% during ischemia and 0.84% ± 1.8% on reperfusion. Penumbral CBF increased from 41.94 ± 13 to 116.5 ± 25 mL per 100 g per minute on reperfusion. On day 7, OC-defined penumbra gave a normal OC response and was located outside the infarct. T*2 OC-defined penumbra recovered when CBF was restored, providing further validation of the utility of T*2 OC for acute stroke management.

Accurate imaging of the ischemic penumbra is a prerequisite for acute clinical stroke research. T 2 * magnetic resonance imaging (MRI) combined with an oxygen challenge (OC) is being developed to detect penumbra based on changes in blood deoxyhemoglobin. However, inducing OC with 100% O 2 induces sinus artefacts on human scans and influences cerebral blood flow (CBF), which can affect T 2 * signal. Therefore, we investigated replacing 100% O 2 OC with 40% O 2 OC (5 minutes 40% O 2 versus 100% O 2 ) and determined the effects on blood pressure (BP), CBF, tissue pO 2 , and T 2 * signal change in presumed penumbra in a rat stroke model. Probes implanted into penumbra and contralateral cortex simultaneously recorded pO 2 and CBF during 40% O 2 (n = 6) or 100% O 2 (n = 8) OC. In a separate MRI study, T 2 * signal change to 40% O 2 (n = 6) and 100% O 2 (n = 5) OC was compared. Oxygen challenge (40% and 100% O 2 ) increased BP by 8.2% and 18.1%, penumbra CBF by 5% and 15%, and penumbra pO 2 levels by 80% and 144%, respectively. T 2 * signal significantly increased by 4.56% ± 1.61% and 8.65% ± 3.66% in penumbra compared with 2.98% ± 1.56% and 2.79%±0.66% in contralateral cortex and 1.09%±0.82% and À0.32%±0.67% in ischemic core, respectively. For diagnostic imaging, 40% O 2 OC could provide sufficient T 2 * signal change to detect penumbra with limited influence in BP and CBF.

A retrospective study of sera from mothers infected with human immunodeficiency virus (HIV-1) was undertaken to investigate whether the titers or affinities of antibodies against the third hypervariable region (V3 loop) of gp120 correlated with transmission of the virus from mother to child. The cohort comprised 7 mothers who transmitted HIV-1 to their children and 20 who did not. Sera were screened for reactivity against two synthetic peptides, one encompassing the entire V3 loop of gp120 (amino acids 297-330) and the other containing an immunodominant epitope from gp41 (amino acids 596-614). Doubling dilutions of sera were tested to obtain antibody titers against both peptides: Anti-gp41 titers were used to normalize the anti-V3 titers. Maternal sera were also screened for the presence of high-affinity antibodies against the V3 peptide. No differences were observed in either titers or affinities of maternal antibodies to the V3 sequence from transmitters and nontransmitters.

Intraoperative blood salvage systems functioned properly and the resultant blood product was superior in terms of red blood cell species. The HemoSep group had significantly better platelet and leukocyte concentrations and fibrinogen content.

Robertson, C, Lodin-Sundström, A, O'Hara, J, King, R, Wainwright, B, and Barlow, M. Effects of pre-race apneas on 400-m freestyle swimming performance. J Strength Cond Res XX(X): 000-000, 2018-This study aimed to establish whether a series of 3 apneas before a 400-m freestyle time-trial affected swimming performance when compared with and combined with a warm-up. Nine (6 males and 3 females) regional to national standard swimmers completed four 400-m freestyle time-trials in 4 randomized conditions: without warm-up or apneas (CON), warm-up only (WU), apneas only (AP), and warm-up and apneas (WUAP). Time-trial performance was significantly improved after WUAP (275.79 ± 12.88 seconds) compared with CON (278.66 ± 13.31 seconds, p = 0.035) and AP (278.64 ± 4.10 seconds, p = 0.015). However, there were no significant differences between the WU (276.01 ± 13.52 seconds, p > 0.05) and other interventions. Spleen volume compared with baseline was significantly reduced after the apneas by a maximum of ∼45% in the WUAP and by ∼20% in WU. This study showed that the combination of a warm-up with apneas could significantly improve 400-m freestyle swim performance compared with a control and apnea intervention. Further investigation into whether long-term apnea training can enhance this response is justified.

IntroductionUncontrolled haemorrhage is the leading cause of death on the battlefield, and two-thirds of these deaths result from non-compressible haemorrhage. Blood salvage and autotransfusion represent an alternative to conventional blood transfusion techniques for austere environments, potentially providing blood to the casualty at point of injury. The aim of this paper is to describe the design, development and initial proof-of-concept testing of a portable blood salvage and autotransfusion technology to enhance survivability of personnel requiring major medical interventions in austere or military environments.MethodA manually operable, dual-headed pump was developed that removes blood from site of injury to a collection reservoir (upper pump) and back to casualty (lower pump). Theoretical flow rate calculations determined pump configuration and a three-dimensionally printed peristaltic pump was manufactured. Flow rates were tested with fresh bovine blood under laboratory conditions representative of the predicted clinical environment.ResultsMathematical modelling suggested flow rates of 3.6 L/min and 0.57 L/min for upper and lower pumps. Using fresh bovine blood, flow rates produced were 2.67 L/min and 0.43 L/min. To mimic expected battlefield conditions, upper suction pump flow rate was calculated using a blood/air mixture.ConclusionThe authors believe that this technology can potentially enhance survivability for casualties in austere and deployed military settings through autotransfusion and cell concentration. It reduces negative effects of blood donation on the conventional donor pool, and potentially negates the logistical constraints associated with allogenic transfusions.