Spontaneous Neutrophil Migration Patterns during Sepsis after Major Burns

Finely tuned to respond quickly to infections, neutrophils have amazing abilities to migrate fast and efficiently towards sites of infection and inflammation. Although neutrophils ability to migrate is perturbed in patients after major burns, no correlations have yet been demonstrated between altered migration and higher rate of infections and sepsis in these patients when compared to healthy individuals. To probe if such correlations exist, we designed microfluidic devices to quantify the neutrophil migration phenotype with high precision. Inside these devices, moving neutrophils are confined in channels smaller than the neutrophils and forced to make directional decisions at bifurcations and around posts. We employed these devices to quantify neutrophil migration across 18 independent parameters in 74 blood samples from 13 patients with major burns and 3 healthy subjects. Blinded, retrospective analysis of clinical data and neutrophil migration parameters revealed that neutrophils isolated from blood samples collected during sepsis migrate spontaneously inside the microfluidic channels. The spontaneous neutrophil migration is a unique phenotype, typical for patients with major burns during sepsis and often observed one or two days before the diagnosis of sepsis is confirmed. The spontaneous neutrophil migration phenotype is rare in patients with major burns in the absence of sepsis, and is not encountered in healthy individuals. Our findings warrant further studies of neutrophils and their utility for early diagnosing and monitoring sepsis in patients after major burns

Bridging thrombolysis in atrial fibrillation stroke is associated with increased hemorrhagic complications without improved outcomes

BACKGROUND: Atrial fibrillation (AF) associated ischemic stroke is associated with worse functional outcomes, less effective recanalization, and increased rates of hemorrhagic complications after intravenous thrombolysis (IVT). Conversely, AF is not associated with hemorrhagic complications or functional outcomes in patients undergoing mechanical thrombectomy (MT). This differential effect of MT and IVT in AF associated stroke raises the question of whether bridging thrombolysis increases hemorrhagic complications in AF patients undergoing MT. METHODS: This international cohort study of 22 comprehensive stroke centers analyzed patients with large vessel occlusion (LVO) undergoing MT between June 1, 2015 and December 31, 2020. Patients were divided into four groups based on comorbid AF and IVT exposure. Baseline patient characteristics, complications, and outcomes were reported and compared. RESULTS: 6461 patients underwent MT for LVO. 2311 (35.8%) patients had comorbid AF. In non-AF patients, bridging therapy improved the odds of good 90 day functional outcomes (adjusted OR (aOR) 1.29, 95% CI 1.03 to 1.60, p=0.025) and did not increase hemorrhagic complications. In AF patients, bridging therapy led to significant increases in symptomatic intracranial hemorrhage and parenchymal hematoma type 2 (aOR 1.66, 1.07 to 2.57, p=0.024) without any benefit in 90 day functional outcomes. Similar findings were noted in a separate propensity score analysis. CONCLUSION: In this large thrombectomy registry, AF patients exposed to IVT before MT had increased hemorrhagic complications without improved functional outcomes, in contrast with non-AF patients. Prospective trials are warranted to assess whether AF patients represent a subgroup of LVO patients who may benefit from a direct to thrombectomy approach at thrombectomy capable centers

Influence of the patient-practitioner interaction context on acupuncture outcomes in functional dyspepsia: study protocol for a multicenter randomized controlled trial

Abstract Background In the treatment of functional dyspepsia, the placebo effect has been reported to be high, and the influence of the patient-practitioner relationship may be a major component of this effect. The specific and non-specific effects of acupuncture cannot be easily distinguished, and the patient-practitioner relationship may influence the total therapeutic effect in clinical practice. There have been no studies that investigate the influence of patient-practitioner relationship on acupuncture treatment for patients with functional dyspepsia. Methods Patients with postprandial distress syndrome, a functional dyspepsia subtype, will be recruited at three hospitals (two in Korea and one in USA) for an international, multi-center, randomized, patient/assessor-blinded, clinical trial. The total anticipated sample size is 88. The participants will be randomly allocated into two groups: an augmented interaction group and a limited interaction group. Acupuncture, with total 12 acupoints, will be performed twice weekly for 4 weeks in both groups. Trained practitioners will provide an “augmented” or “limited” interaction context, as determined by random allocation. The primary outcome measure is the proportion of responders, the proportion of participants who answer “yes” to more than half of the adequate relief questions during the study. Secondary outcome measures include questionnaires for quality of life and symptoms of dyspepsia, and maximum tolerable volume of nutrient drink test. Data will be collected at baseline and following 4 weeks of acupuncture. Discussion This study will evaluate the influence of the patient-practitioner interaction on clinical effects of acupuncture in patients with functional dyspepsia. Trial registration CRIS Identifier: ( KCT0002229 )

The components and temporal evolution of neutrophil spontaneous migration score (NAS_N) in patients with major burns.

<p>(A) Two dimensional comparisons between neutrophil migration parameters between healthy donors (black stars), burn patients with no complications (green square), SIRS (green triangle), and sepsis (red square). In the absence of chemoattractant, neutrophils from patients with sepsis migrate in larger numbers and display more oscillatory migration than the patients with SIRS or those from healthy donors (which do not migrate). (B) Neutrophils from patients with sepsis migrate longer distances and display more oscillatory migration than the patients with SIRS or those from healthy donors (which do not migrate). (C) Changes in the neutrophil activation score in the 6 patients with no sepsis during the hospital stay. On patient that died is indicated (red cross). (D) Changes in the neutrophil activation score in the 7 patients that experience sepsis during the hospital stay. Higher scores are observed during sepsis (filled red triangle). In patients that respond to antibiotic treatment, NAS_N decreases when sepsis is resolved (empty red triangles). In some of the patients, NAS_N increased even several days before sepsis was diagnosed (red star). The NAS_N remained low in these patients in the absence of complications (empty gray triangle).</p

Correlations between the changes in neutrophil spontaneous migration score (NAS_N) and the timing of sepsis in burn patients.

<p>(A) Neutrophil activation score averages are significantly different between burn patients with sepsis (N = 21) and patients with SIRS (N = 29, P = 0.038) or patients with no SIRS (N = 21, P = 0.027). (B) The NAS_N is significantly higher in patients in samples before clinical diagnosis (P = 0.036) and drops to one third following septic diagnosis and post-antibiotic therapy. (C) ROC curves for averaged NAS_N of two successive blood samples demonstrates the good predictive values of the spontaneous neutrophil migration patterns for sepsis in patients with major burns.</p

Measuring neutrophil migration in burn patients during sepsis.

<p>(A) Overview of the protocol using microfluidic devices to measure neutrophil migration in patients with major burns. (1) Three milliliters blood samples are obtained from patients with major burns. (2) Neutrophils are separated from blood using negative selection beads. (3) Microfluidic devices are primed with chemoattractant solutions and patient neutrophils are introduced into the neutrophil loading channel. (4) Neutrophils are observed using time-lapse imaging during migration through 3×6 µm channels and mazes of channels. (5) Images of moving neutrophils are recorded at single cells resolution and analyzed to quantify 18 neutrophil migratory parameters. (6) A neutrophil spontaneous motility score is calculated for each sample. (7) Correlations are tested between the Neutrophil activation score (NAS_N) and sepsis in patients with major burns. This cycle is repeated every two days or less often for the duration of burn patient treatment, up to one month. (B) Typical timeline for sample collection from burn patients. During the first phase, samples are collected every two days for one week. A second phase continues with one sample every week for up to one month. A third phase is triggered by the clinicians when there is request for blood cultures, signs of fever, leukocytosis and/or thrombocytosis. During Phase three, samples are collected every two days for a week.</p

Neutrophil migration parameters in burn patients.

<p>(A) Heat-map showing the results of 18 neutrophil migratory phenotype measurements in 74 blood samples from 13 burn patients and three healthy volunteers. Specific measurements are explained in detail in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0114509#pone-0114509-t002" target="_blank">Table 2</a>, including averages for each parameter. Each parameter was measured in three conditions: in the absence of chemoattractant, and in the presence of fMLP and LTB₄ chemoattractant gradients. Bright green illustrates 2 S.D. below healthy donor averages, light green illustrates 1 S.D. below healthy donor averages, bright red illustrates 2 S.D. above healthy donor averages, and light red illustrates 1 S.D. above healthy donor averages. Below the heat map, a color coded bar represents the status of the blood donor at the time of the draw. Red illustrates sepsis, green illustrates SIRS, and black illustrates no SIRS status. The day post burn is indicated above the bar, the patient identifier is presented below the bar. Healthy donors, burn patients with sepsis, and burn patients without sepsis are grouped by the accolades. (B) Kymograph showing an example of oscillatory migration of a neutrophil from a septic burn-patient, in the absence of chemoattractant. The time interval between successive frames is 2 minutes. Vertical scale bar is 100 µm.</p

Summary of neutrophil phenotypic migration parameters to an array of chemoattractants (no chemoattractant, fMLP, and LTB₄).

<p>Averages +/− standard deviations are shown for all parameters for both healthy donors and burn patients. • indicates average parameters that are significantly different between healthy donors and burn patients, (p<0.05)</p><p>Summary of neutrophil phenotypic migration parameters to an array of chemoattractants (no chemoattractant, fMLP, and LTB₄).</p