Double dose vs. standard dose influenza vaccination in patients with heart failure: a pilot study.

AIMS: Influenza infection leads to increased morbidity and mortality in those with heart failure, and individuals with heart failure exhibit reduced antibody responses to influenza vaccine. We hypothesized that patients with heart failure randomized to double dose (DD) influenza vaccine will mount more vigorous humoral immune responses compared with those given standard dose (SD) vaccine. METHODS AND RESULTS: We randomized 28 heart failure patients to DD (30 µg/strain) or SD (15 µg/strain) influenza vaccine. We assessed antibody production by haemagglutination inhibition assay (reported as log haemagglutination units) prior to, at 2-4 weeks and at 4-6 months following vaccination. Baseline antibody titres between DD (n = 12, mean age 64 ± 10 years) and SD (n = 16, mean age 63 ± 9 years) did not differ significantly. At 2-4 weeks, DD haemagglutination unit changes were significantly higher than those of SD (3.3 vs. 1.6 for A/H3N2, P < 0.001; 1.9 and 1.1 for A/H1N1, P = 0.009; and 1.7 and 1 for B-type, P = 0.02). At 4-6 weeks, there were no differences in titres in any of the virus types between treatment groups and, although titres decreased, levels remained above the seroprotective threshold. CONCLUSIONS: Higher influenza vaccine doses may elicit increased antibody-mediated responses in patients with heart failure; further studies should assess whether clinical outcomes are improved with this strategy.

Decreased immune responses to influenza vaccination in patients with heart failure.

BACKGROUND: Heart failure (HF) patients are at risk for influenza despite widespread vaccination. Both humoral (antibody) and cytotoxic T-lymphocyte (CTL) responses are important for protection. We explored antibody- and CTL-mediated responses to the influenza vaccine in HF patients compared with healthy controls. METHODS AND RESULTS: We studied 29 HF patients (9 ischemic, 20 nonischemic) stable on HF therapies and 17 healthy controls. Participants had phlebotomy before and after influenza vaccination. Antibody production was measured in serum by hemagglutination inhibition assay and CTL responses (via interferon [IFN]-gamma and interleukin [IL]-10 production) were measured in isolated peripheral blood mononuclear cells with enzyme-linked immunosorbent assay. CTL responses demonstrated increased IL-10 production in HF patients after vaccination (P = .002), but similar IFN-gamma responses to healthy controls. All participants demonstrated antibody seroprotection; groups had similar rates of seroconversion (P = NS). Antibody-mediated response to the newest vaccine antigen, H3N2, was reduced in HF (P = .009). CONCLUSIONS: Patients with HF had higher vaccine induced IL-10 concentrations, suggesting a different CTL phenotype for vaccine responses. HF patients did not mount as vigorous of an antibody immune response to the newest vaccine viral strain compared with healthy individuals. These data suggest that immunologic memory may be important for vaccine protection in HF patients.

Evidence for a frontal cortex role in both auditory and somatosensory habituation: a MEG study.

Auditory and somatosensory responses to paired stimuli were investigated for commonality of frontal activation that may be associated with gating using magnetoencephalography (MEG). A paired stimulus paradigm for each sensory evoked study tested right and left hemispheres independently in ten normal controls. MR-FOCUSS, a current density technique, imaged simultaneously active cortical sources. Each subject showed source localization, in the primary auditory or somatosensory cortex, for the respective stimuli following both the first (S1) and second (S2) impulses. Gating ratios for the auditory M50 response, equivalent to the P50 in EEG, were 0.54+/-0.24 and 0.63+/-0.52 for the right and left hemispheres. Somatosensory gating ratios were evaluated for early and late latencies as the pulse duration elicits extended response. Early gating ratios for right and left hemispheres were 0.69+/-0.21 and 0.69+/-0.41 while late ratios were 0.81+/-0.41 and 0.80+/-0.48. Regions of activation in the frontal cortex, beyond the primary auditory or somatosensory cortex, were mapped within 25 ms of peak S1 latencies in 9/10 subjects during auditory stimulus and in 10/10 subjects for somatosensory stimulus. Similar frontal activations were mapped within 25 ms of peak S2 latencies for 75% of auditory responses and for 100% of somatosensory responses. Comparison between modalities showed similar frontal region activations for 17/20 S1 responses and for 13/20 S2 responses. MEG offers a technique for evaluating cross modality gating. The results suggest similar frontal sources are simultaneously active during auditory and somatosensory habituation.

Characterization of polylactic acid-polyglycolic acid composites for cartilage tissue engineering.

The objective of this study was to determine the effects of scaffold composition on the physical properties, adhesion, and growth of bovine articular chondrocytes on polylactic acid (PLA)/polyglycolic acid (PGA) composites. Nonwoven meshes of PGA were coated with PLA, using a solvent evaporation technique that resulted in composites with fractional PLA contents ranging from 0 to 68%. The compressive modulus of scaffolds increased linearly with the addition of PLA, ranging from less than 1 kPa for PGA to approximately 20 kPa for scaffolds with 68% PLA content. The characteristic degradation time of these scaffolds also increased from approximately 5 days for 0% PLA to 45 days for 68% PLA. Addition of PLA decreased cell seeding efficiency from 48% for 0% PLA scaffolds to 27% for 68% PLA scaffolds. Cells seeded onto 27% PLA scaffolds increased 3-fold in number over 4 weeks in culture, whereas cells seeded onto 68% PLA increased only 2-fold in number. Scanning electron microscopy indicated that cells attached to PGA appeared flat with many small processes, whereas those attached to PLA were more rounded. These studies provide important information for the design of scaffolds for cartilage tissue engineering.

Experimental coronary artery occlusion: relevance to off-pump cardiac surgery.

Mechanical coronary artery occlusion is required for minimally invasive direct coronary artery bypass and off-pump coronary artery bypass surgery. It is important that the method of occlusion be minimally traumatic. Chronic effects of these methods have never been studied. Temporary occlusion of coronaries utilizing suture snare, silastic loop snare, and bulldog clamp was carried out in 12 Yucatan pigs. Three animals each were sacrificed acutely and at 3, 6, and 12 months. The area of occlusion of each vessel was examined by light microscopy and the degree of damage recorded. In the animals sacrificed acutely, there was more damage using the suture snare than with the other 2 methods, but there was minimal damage at longer intervals. There was slight damage acutely and chronically with the bulldog technique. No damage was seen acutely with the silastic loop technique, but some late damage was found. The techniques of coronary artery dissection and occlusion used for minimally invasive and off-pump bypass surgery may contribute to early postoperative graft occlusion.

Programa de recuperación rápida (Fast Track) en la cirugía de revascularización miocárdica: análisis de sus implicancias médicas y económicas / Fast track program for recovery from coronary artery surgery: medical and economic implications

El programa de recuperación rápida (Fast Track) consiste en una serie de intervenciones perioperatorias que les permite a los pacientes sometidos a cirugía de revascularización miocárdica recuperar el nivel de salud y actividad más rápido y con mejor expectativa de vida. Ciento dos pacientes sometidos a cirugía de revascularización miocárdica fueron enrolados en el Fast Track. Resultados: el 63 por ciento de los pacientes fue dado de alta en el quinto día posoperatorio o antes. No hubo mortalidad asociada con el Fast Track y la única reinternación (1 por ciento) no estuvo relacionada con el programa. Se concluye que el Fast Track es efectivo y seguro

Programa de recuperación rápida (Fast Track) en la cirugía de revascularización miocárdica: análisis de sus implicancias médicas y económicas / Fast track program for recovery from coronary artery surgery: medical and economic implications

El programa de recuperación rápida (Fast Track) consiste en una serie de intervenciones perioperatorias que les permite a los pacientes sometidos a cirugía de revascularización miocárdica recuperar el nivel de salud y actividad más rápido y con mejor expectativa de vida. Ciento dos pacientes sometidos a cirugía de revascularización miocárdica fueron enrolados en el Fast Track. Resultados: el 63 por ciento de los pacientes fue dado de alta en el quinto día posoperatorio o antes. No hubo mortalidad asociada con el Fast Track y la única reinternación (1 por ciento) no estuvo relacionada con el programa. Se concluye que el Fast Track es efectivo y seguro (AU)