The impact of beta‐blocker therapy on anemia after traumatic brain injury

BACKGROUND: An increase in endogenous catecholamine levels after traumatic brain injury (TBI) is well described. Animal studies suggest that postinjury anemia is exacerbated by a persistent hyperadrenergic state. This study aims to determine if beta‐blocker (BB) exposure affects anemia after TBI. STUDY DESIGN AND METHODS: We reviewed a Level I trauma registry for patients with TBI, examining markers of anemia between patients who received BB with those who did not. RESULTS: A total of 174 patients were exposed to BB (BB+) and 245 were not exposed (BB?). The mean age in the BB+ group was 50 years (vs. 36 years in BB? group, p < 0.001). The mean injury severity score was 33.6 for the BB+ group (vs. 30.8 for BB? group, p = 0.01). While BB+ patients were more likely to receive a transfusion (60.9% vs. 35.1%, p < 0.001), BB+ patients reached their nadir hemoglobin (Hb) at a later day of hospitalization and their rate of decrease in Hb was significantly slower (both p < 0.001). Choosing Hb cutoffs for anemia of both 7 and 10 g/dL, Kaplan‐Meier demonstrated a significant delay in time to anemia. CONCLUSION: This study suggests beta‐blockade delays anemia after TBI. Elaboration of this effect may demonstrate an additional benefit of beta‐blockade after head injury.     

Activated microglia proliferate at neurites of mutant huntingtin-expressing neurons

In Huntington's disease (HD), mutated huntingtin (mhtt) causes striatal neurodegeneration which is paralleled by elevated microglia cell numbers. In vitro corticostriatal slice and primary neuronal culture models, in which neuronal expression of mhtt fragments drives HD-like neurotoxicity, were employed to examine wild type microglia during both the initiation and progression of neuronal pathology. As neuronal pathology progressed, microglia initially localized in the vicinity of neurons expressing mhtt fragments increased in number, demonstrated morphological evidence of activation, and expressed the proliferation marker, Ki67. These microglia were positioned along irregular neurites, but did not localize with mhtt inclusions nor exacerbate mhtt fragment-induced neurotoxicity. Prior to neuronal pathology, microglia upregulated ionized calcium binding adaptor molecule 1 (Iba1), signaling a functional shift. With neurodegeneration, interleukin-6 and complement component 1q were increased. The results suggest a stimulatory, proliferative signal for microglia present at the onset of mhtt fragment-induced neurodegeneration. Thus, microglia effect a localized inflammatory response to neuronal mhtt expression that may serve to direct microglial removal of dysfunctional neurites or aberrant synapses, as is required for reparative actions in vivo.     

Use of the Colonoscope Training Model with the Colonoscope 3D Imaging Probe Improved Trainee Colonoscopy Performance: A Pilot Study

Background

Colonoscopy insertion is difficult to teach due to the inability of current training models to provide realistic tactile sensation with simultaneous three-dimensional (3D) colonoscope display.

Aims

To assess the influence of a simulator consisting of a colon model coupled with 3D instrument visualization on trainee colonoscopy performance.

Methods

Pilot study using the simulator model with three trainees who were not proficient in colonoscopy. At random times over a 6-week period, trainees participated in an individualized half-day session using the Colonoscope Training Model and a colonoscope equipped with a 3D magnetic probe imaging system (ScopeGuide) in six standardized cases. A blinded supervising instructor graded patient-based colonoscopy performance over the 6-week period, and we independently analyzed the 2-week period before and after the intervention. We also measured cecal intubation and withdrawal times and medication requirements.

Results

Trainees performed 86 patient-based colonoscopies. Following the intervention, the colonoscopy performance score improved from 4.4 ± 2.3 to 5.9 ± 2.4 (p = 0.005). Trainees had a 76% cecal intubation rate following the session as compared to 43% before training (p = 0.004), while utilizing less time, 14 ± 7 versus 18 ± 11 min (p = 0.056) and less medication (p > 0.05).

Conclusions

Colonoscopy simulation using the Colonoscope Training Model and the ScopeGuide produced an immediate and large effect on trainee colonoscopy performance.     

Effects of a short-term personalized intermittent work exercise program (IWEP) on maximal cardio-respiratory function and endurance parameters among healthy young and older seniors

Objective

The aim of this study was to evaluate the efficiency of a short-term Intermittent Work Exercise Program (IWEP) among healthy elderly subjects.

Study design and setting

This longitudinal prospective study took place at the Strasbourg University Hospital geriatric department.

Study participants

One hundred and fifty older volunteers, previously determined as being free from cardiac and pulmonary disease, were separated into two age groups: the “young senior” (60.2 ± 3.1 yr) and the “older senior” groups (70.8 ± 5.2 yr).These groups were then subdivided by gender into the “young female senior”, “young male senior” “older female senior” and “older male senior” groups.

Intervention

Before and after the IWEP, all subjects were asked to perform an incremental cycle exercise to obtain their first ventilatory threshold (VT₁), maximal tolerated power (MTP), peak oxygen uptake (VO_2peak) and maximal minute ventilation (MMV). The IWEP consisted of a 30-min cycling exercise which took place twice a week, and was divided into six 5-min stages consisting of 4 min at VT₁ intensity and 1 min at 90% MTP.

Measurements

An assessment was made of the effects of the IWEP on maximal cardio-respiratory function (MTP, VO_2peak, MMV) and endurance parameters (VT₁, heart rate [HR] measured at pretraining VT₁ and lactate concentrations at pre-training MTP).

Results

This short-term training program resulted in a significant increase of MTP (from 13.2% to 20.6%), VO_2peak (from 8.9% to 16.6%) and MMV (from 11.1% to 21.8%) in all groups (p<0.05). VT1 improved from 21% at pretraining to 27%, while HR at pre-training VT1 as well as lactate concentrations at pre-training MTP decreased significantly in all groups (p<0.05). The post-training values for VO_2peak and MMV of the “older seniors” were not significantly different (p>0.05) from the “young seniors” pre-training values for the same parameters.

Conclusion

The most striking finding in this study is that after only 9 weeks, our short-term “individually-tailored” IWEP significantly improved both maximal cardio-respiratory function and endurance parameters in healthy, previously untrained seniors.     

Evaluation of microwave ablation of liver malignancy with enabled constant spatial energy control to achieve a predictable spherical ablation zone

Objectives: To evaluate the clinical performance of a new microwave ablation (MWA) system with enabled constant spatial energy control (ECSEC) to achieve spherical ablation zones in the treatment of liver malignancies.

Materials and methods: In this retrospective study, 56 hepatic tumours in 48 patients (23 men, 25 women; mean age: 59.6 years) were treated using a new high-frequency MWA-system with ECSEC. Parameters evaluated were technical success, technical efficacy, tumour diameter, tumour and ablation volume, complication rate, 90-day mortality, local tumour progression (LTP) at the 12-month follow-up, ablative margin and ablation zone sphericity. These parameters were compared using the Kruskal–Wallis test with the same parameters collected retrospectively from cohorts of patients treated with conventional high-frequency (HF) MWA (n?=?20) or low-frequency (LF) MWA (n?=?20).

Results: Technical success was achieved in all interventions. The technical efficacy was 100% (ECSEC) vs. 100% (LF-MWA) vs. 95% (HF-MWA). There were no intra-procedural deaths or major complications. Minor complications occurred in 3.57% (2/56), 0% (0/20) and 0% (0/20) of the patients, respectively. The one-year mortality rate was 16.1% (9/56), 15% (3/20) and 10% (2/20), respectively. The LTP was 3.57% (2/56), 5% (1/20) and 5% (1/20), respectively. The median deviation from ideal sphericity (1.0) was 0.135 (ECSEC) vs. 0.344 (LF-MWA) vs. 0.314 (HF-MWA) (p?p?Conclusions: Microwave ablation of liver malignancies is a safe and efficient treatment independent of the system used. Hepatic MWA with ECSEC achieves significantly more spherical ablation zones and higher minimal ablative margins.     

Murine immunoglobin response to sterile talc injection

Mice were injected subcutaneously with sterile talc, and the changes in serum IgG, IgM, and IgA were investigated at various time intervals. Three talc-injection schedules were used: a single injection of talc; a double injection of talc; and two injections of talc at different times. The results showed that: (1) a single injection of talc resulted in an increase in serum IgM at 24 hr, and an increase in IgG at 24–48 hr; (2) a double injection of talc did not result in a significant difference in immunoglobulin levels from those observed after a single injection; (3) two injections of talc given at different times did not result in a response greater than that observed following a single injection of talc. No changes from control values were observed in IgA. No evidence for the presence of an antigen was found.