Time-varying phase synchronization of resting-state functional magnetic resonance imaging reveals a shift toward self-referential processes during sustained pain

ABSTRACT

Growing evidence has suggested that time-varying functional connectivity between different brain regions might underlie the dynamic experience of pain. This study used a novel, data-driven framework to characterize the dynamic interactions of large-scale brain networks during sustained pain by estimating recurrent patterns of phase-synchronization. Resting-state functional magnetic resonance imaging signals were collected from 50 healthy participants before (once) and after (twice) the onset of sustained pain that was induced by topical application of capsaicin cream. We first decoded the instantaneous phase of neural activity and then applied leading eigenvector dynamic analysis on the time-varying phase-synchronization. We identified 3 recurrent brain states that show distinctive phase-synchronization. The presence of state 1, characterized by phase-synchronization between the default mode network and auditory, visual, and sensorimotor networks, together with transitions towards this brain state, increased during sustained pain. These changes can account for the perceived pain intensity and reported unpleasantness induced by capsaicin application. In contrast, state 3, characterized by phase-synchronization between the cognitive control network and sensory networks, decreased after the onset of sustained pain. These results are indicative of a shift toward internally directed self-referential processes (state 1) and away from externally directed cognitive control processes (state 3) during sustained pain.

Measurement of protein concentration in bacteria and small organelles under a light transmission microscope

Protein concentration (PC) is an essential characteristic of cells and organelles; it determines the extent of macromolecular crowding effects and serves as a sensitive indicator of cellular health. A simple and direct way to quantify PC is provided by brightfield-based transport-of-intensity equation (TIE) imaging combined with volume measurements. However, since TIE is based on geometric optics, its applicability to micrometer-sized particles is not clear. Here, we show that TIE can be used on particles with sizes comparable to the wavelength. At the same time, we introduce a new ImageJ plugin that allows TIE image processing without resorting to advanced mathematical programs. To convert TIE data to PC, knowledge of particle volumes is essential. The volumes of bacteria or other isolated particles can be measured by displacement of an external absorbing dye ("transmission-through-dye" or TTD microscopy), and for spherical intracellular particles, volumes can be estimated from their diameters. We illustrate the use of TIE on Escherichia coli, mammalian nucleoli, and nucleolar fibrillar centers. The method is easy to use and achieves high spatial resolution.

[Research progress on pyroptosis in liver diseases]

Pyroptosis is a newly discovered kind of cell death modality that, due to its association with innate immunity, plays a crucial role in cytolysis and inflammatory cytokine release during host defense against infection. In recent years, studies have shown that pyroptosis plays an important role in the occurrence and development of liver diseases. This article introduces and elaborates on the most recent research progress on pyroptosis in liver diseases based on the morphological features, molecular and pathophysiological mechanisms.

Impact of Lymphopenia on Definitive Treatment of Locally Advanced Cervical Cancer

PURPOSE/OBJECTIVE(S)

Pre-treatment lymphopenia prior to initiating treatment has been correlated with reduced survival in a number of different cancers. The purpose of this study is to evaluate the association between lymphopenia and survival in women with locally advanced cervical cancer (LACC) treated with primary chemoradiation (CRT).

MATERIALS/METHODS

We retrospectively reviewed patients with LACC treated at a single institution from 2005 - 2021 with available lymphocyte information. Patient and treatment characteristics were recorded including age, tumor size and stage, EBRT dose/fractionation, and brachytherapy dosimetry data. Absolute lymphocyte counts (ALC) were collected prior to initiating CRT and at 3-month intervals following CRT and graded based on severity of lymphopenia using CTCAE v 5.0. Overall survival (OS), progression free survival (PFS), and local control (LC) were calculated from the start of treatment to date of last follow-up. Kaplan-Meier survival analysis was performed to evaluate whether lymphocyte changes were associated with OS, PFS, or LC.

RESULTS

A total of 124 patients met study inclusion criteria with stage IB - IV disease (41 stage I, 41 stage II, 36 stage III, 6 stage IV) and a median follow up of 3.6 years (range 0.2-16.5 years). The median age was 49 years (range 26-77). The median EBRT dose was 45 Gy (range: 26-57.5 Gy) and 44.2% of patients received para-aortic (PA) nodal EBRT (28.8% elective and 15.4% with positive PA nodes). 5-year OS, PFS, and LC were 60.3% (95% CI 51.5-70.7), 47.5% (95% CI 39-58), and 75.5% (95% CI 67.3-82.9), respectively. Pre-treatment lymphopenia (ALC <1000 cells/mm3) was present in 11 (9%) patients. When the total cohort was divided into patients with and without pre-treatment lymphopenia, OS was statistically improved in the patients without baseline lymphopenia, with a 5-year OS of 63.2% (95% CI 53.9-73.9) versus 35.3% (95% CI 14.5-86.3) in the lymphopenia group (p = 0.034). LC also trended to being improved in the patients without lymphopenia, though this did not reach statistical significance in our small sample size of lymphopenic patients, with 5-year LC of 76.8% (95% CI 68.4-84.3) versus 67.5% (05% CI 36.6-93.8), p = 0.45.

CONCLUSION

In this single institution experience of LACC treated with definitive CRT, we found that baseline lymphopenia is associated with inferior OS. Patients with higher pre-CRT ALC may represent a population with more robust immune systems, producing more favorable tumor responses to treatment. Additional studies are warranted to investigate the evolving role of combined EBRT and systemic therapy in LACC.

THE CLINICAL SIGNIFICANCE OF COMPLETE BLOOD COUNT, NEUTROPHIL-TO-LYMPHOCYTE RATIO, AND MONOCYTE-TO-LYMPHOCYTE RATIO IN GESTATIONAL DIABETES MELLITUS

Background

To investigate the association between inflammatory factors, such as complete blood count (CBC) components, neutrophil/lymphocyte ratio (NLR), monocyte/lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), and gestational diabetes mellitus (GDM).

Methods

A total of 635 pregnant women with GDM and 296 with normal pregnancies at 7-13 weeks of gestation who underwent prenatal examinations in the obstetrics department were enrolled (June 2020-December 2020). CBC parameters, including WBC, neutrophil, lymphocyte (LYM), monocyte (MON), red blood cell (RBC), hemoglobin (HGB), mean corpuscular volume (MCV), platelet (PLT), platelet accumulation (PCT), mean platelet volume (MPV), NLR, MLR, PLR, alanine transaminase (ALT), aspartate transaminase (AST), gamma-glutamyl transferase (GGT), and other parameters were assessed. The receiver operating characteristic (ROC) curve was used to analyze the screening effects of the variables on the development of GDM.

Results

There were significant differences in the blood levels of WBC, NEU, LYM, MON, RBC, HGB, PCT, ALT, AST, GGT, NLR, and MLR between the GDM and control groups (P<0.05). The diagnostic level of MON was the highest among all factors.

Conclusion

Inflammatory factors (WBC, NEU, LYM, MON, NLR, and MLR counts) were correlated with GDM.

Evaluation of National Conference-Associated Medical Student Research and Mentorship Award for Medical Students, Resident Mentors, and Radiation Oncologist Supervisors

PURPOSE/OBJECTIVE(S)

In 2020, the Canadian Association of Radiation Oncology (CARO) Medical Student Research and Mentorship Award (CARO MSRMA) was created to support medical students pursuing radiation oncology (RO) research and RO as a career. This study aims to evaluate the impact of three consecutive years of this award on medical students, RO resident mentors, and research supervisors.

MATERIALS/METHODS

Medical student mentees, resident mentors, and staff RO research supervisors who participated in one of three iterations of CARO MSRMA (2020-2022 inclusive) were identified. Three separate surveys were developed for these groups using best practice strategies for medical education surveys and circulated for peer-review amongst experts in oncology medical education. The surveys were sent to 52 participants: 18 medical students (Group 1), 18 RO resident mentors (Group 2), and 16 attending RO supervisors (Group 3). After anonymization, quantitative answers were analyzed using descriptive statistics and narrative responses were evaluated using a grounded theory approach.

RESULTS

Survey response rate was 92% (48/52). For Group 1, the award maintained (71%) or increased interest in pursuing an RO career (24%). Aspects of the award rated most important were: financial support to attend the CARO Annual Scientific Meeting (mean rating 4.8/5) and mentorship with an RO resident (mean rating 4.6/5). Through mentorship, 60% of students obtained valuable information about a career in RO, 60% reported helpful residency matching (CaRMS) advice, and another 60% attained insight into RO residency. For Group 2 respondents, 100% felt the program either maintained or increased their motivation to mentor students in RO. For Group 3, 100% agreed or strongly agreed that they enjoyed their role as a supervisor, would participate in the program again, and would recommend the opportunity to others. All three Groups agreed or strongly agreed that it would be useful for CARO to create a virtual network of radiation oncologists, residents, and medical students to share and access shadowing and research opportunities to encourage national RO exposure and collaboration. The first cohort of medical student awardees has CaRMS matching results, with approximately 50% matching to RO.

CONCLUSION

A national conference-associated medical student research and mentorship award has had a positive impact on all three populations involved: medical students in motivation to continue pursuing RO research and career opportunities, RO resident mentors in enhancing mentorship skills, and attending supervisors in inspiring the next generation of prospective RO colleagues. Further research is recommended to determine the impact of the award on subsequent Residency Specialty matching, and whether expansion of this award to other opportunities may be beneficial.

Neurocognitive Mechanisms Underlying Attention Bias Towards Pain: Evidence From a Drift-Diffusion Model and Event-Related Potentials

Although combining computational modeling with event-related potentials (ERPs) can precisely characterize neurocognitive processes involved in attention bias, it has yet to be applied in the context of pain. Here, a hierarchical drift-diffusion model (DDM) along with ERPs was used to characterize the neurocognitive mechanisms underlying attention bias towards pain. A spatial cueing paradigm was adopted, in which the locations of targets were either validly or invalidly predicted by spatial cues related to pain or nonpain signals. DDM-derived nondecision time was shorter for targets validly cued by pain signals than by nonpain signals, thus indicating speeded attention engagement towards pain; drift rate was slower for targets invalidly cued by pain signals than by nonpain signals, reflecting slower attention disengagement from pain. The facilitated engagement towards pain was partially mediated by the enhanced lateralization of cue-evoked N1 amplitudes, which relate to the bottom-up, stimulus-driven processes of detecting threatening signals. On the other hand, the retarded disengagement from pain was partially mediated by the enhanced target-evoked anterior N2 amplitudes, which relate to the top-down, goal-driven processes of conflict monitoring and behavior regulating. These results demonstrated that engagement and disengagement components of pain-related attention bias are governed by distinct neurocognitive mechanisms. However, it remains possible that the findings are not pain-specific, but rather, are related to threat or aversiveness in general. This deserves to be further examined by adding a control stimulus modality. PERSPECTIVE: This study characterized the neurocognitive processes involved in attention bias towards pain through combining a hierarchical DDM and ERPs. Our results revealed distinctive neurocognitive mechanisms underlying engagement and disengagement components of attention bias. Future studies are warranted to examine whether our findings are pain-specific or not.

Aftereffects of alpha transcranial alternating current stimulation over the primary sensorimotor cortex on cortical processing of pain

ABSTRACT

Transcranial alternating current stimulation (tACS) is believed to modulate brain oscillations in a frequency-specific manner. Given the correlation between sensorimotor α-oscillations and pain perception, tACS that targets sensorimotor α-oscillations has the potential to reduce pain. Therefore, this study sought to determine the aftereffects of α-tACS over unilateral primary sensorimotor cortex (SM1) on the perceptual and neural responses to noxious painful stimulation of the contralateral hand. Using a double-blinded and sham-controlled design, 60 healthy participants were recruited to receive either α-tACS or sham stimulation of unilateral SM1 through an electrode montage in a 4 × 1 ring configuration. Neural responses to laser nociceptive stimuli were assessed using functional magnetic resonance imaging immediately before and after α-tACS intervention. Perceptual reports were recorded simultaneously. Compared with sham stimulation, α-tACS attenuated bilateral SM1 responses to painful stimuli delivered to the contralateral hand. Although α-tACS did not exert direct effect on subjective pain perception, it can indirectly decrease ratings of pain perception by reducing brain activity within the targeted SM1. Moreover, α-tACS decreased the functional connectivity between the targeted SM1 and a network of regions that are crucially involved in pain processing, including the middle cingulate cortex, contralateral somatosensory cortex, and dorsolateral prefrontal cortex. These results demonstrated that after α-tACS applied over the unilateral SM1 does attenuate subsequent neural processing of pain within bilateral sensorimotor regions as well as sensorimotor functional connectivity. The findings provide evidence that sensorimotor α-oscillations directly affect pain processing and support the application of sensorimotor α-tACS for inducing pain analgesia.

Computational approaches for the reconstruction of optic nerve fibers along the visual pathway from medical images: a comprehensive review

Optic never fibers in the visual pathway play significant roles in vision formation. Damages of optic nerve fibers are biomarkers for the diagnosis of various ophthalmological and neurological diseases; also, there is a need to prevent the optic nerve fibers from getting damaged in neurosurgery and radiation therapy. Reconstruction of optic nerve fibers from medical images can facilitate all these clinical applications. Although many computational methods are developed for the reconstruction of optic nerve fibers, a comprehensive review of these methods is still lacking. This paper described both the two strategies for optic nerve fiber reconstruction applied in existing studies, i.e., image segmentation and fiber tracking. In comparison to image segmentation, fiber tracking can delineate more detailed structures of optic nerve fibers. For each strategy, both conventional and AI-based approaches were introduced, and the latter usually demonstrates better performance than the former. From the review, we concluded that AI-based methods are the trend for optic nerve fiber reconstruction and some new techniques like generative AI can help address the current challenges in optic nerve fiber reconstruction.

[Clinical features of primary sclerosing cholangitis and inflammatory bowel disease]

Objective: To explore disease characteristics of primary sclerosing cholangitis (PSC) and inflammatory bowel disease (IBD) and compare the differences between PSC with and without IBD. Methods: Study design was cross sectional. Forty-two patients with PSC who were admitted from January 2000 to January 2021 were included. We analyzed their demographic characteristics, clinical manifestations, concomitant diseases, auxiliary examination, and treatment. Results: The 42 patients were 11-74(43±18) years of age at diagnosis. The concordance rate of PSC with IBD was 33.3%, and the age at PSC with IBD diagnosis was 12-63(42±17) years. PSC patients with IBD had higher incidences of diarrhea and lower incidences of jaundice and fatigue than in those without IBD (all P<0.05). Alanine aminotransferase, total bilirubin, direct bilirubin, total bile acid and carbohydrate antigen 19-9 levels were higher in PSC patients without IBD than in those with IBD (all P<0.05). The positive rates for antinuclear antibodies and fecal occult blood were higher in PSC patients with IBD than in those without IBD (all P<0.05). Patients with PSC complicated with ulcerative colitis mainly experienced extensive colonic involvement. The proportion of 5-aminosalicylic acid and glucocorticoid application in PSC patients with IBD was significantly increased compared with that of PSC patients without IBD (P=0.025). Conclusions: The concordance rate of PSC with IBD is lower at Peking Union Medical College Hospital than in Western countries. Colonoscopy screening may benefit PSC patients with diarrhea or fecal occult blood-positive for early detection and diagnosis of IBD.

Temporal dynamics of electroencephalographic microstates during sustained pain

Brain dynamics can be modeled by a sequence of transient, nonoverlapping patterns of quasi-stable electrical potentials named "microstates." While electroencephalographic (EEG) microstates among patients with chronic pain remained inconsistent in the literature, this study characterizes the temporal dynamics of EEG microstates among healthy individuals during experimental sustained pain. We applied capsaicin (pain condition) or control (no-pain condition) cream to 58 healthy participants in different sessions and recorded resting-state EEG 15 min after application. We identified 4 canonical microstates (A-D) that are related to auditory, visual, salience, and attentional networks. Microstate C had less occurrence, as were bidirectional transitions between microstate C and microstates A and B during sustained pain. In contrast, sustained pain was associated with more frequent and longer duration of microsite D, as well as more bidirectional transitions between microstate D and microstates A and B. Microstate D duration positively correlated with intensity of ongoing pain. Sustained pain improved global integration within microstate C functional network, but weakened global integration and efficiency within microstate D functional network. These results suggest that sustained pain leads to an imbalance between processes that load on saliency (microstate C) and processes related to switching and reorientation of attention (microstate D).

Gyrus rectus asymmetry predicts trait alexithymia, cognitive empathy, and social function in neurotypical adults

Reduced empathy and elevated alexithymia are observed in autism spectrum disorder (ASD), which has been linked to altered asymmetry in brain morphology. Here, we investigated whether trait autism, empathy, and alexithymia in the general population is associated with brain morphological asymmetry. We determined left-right asymmetry indexes for cortical thickness and cortical surface area (CSA) and applied these features to a support-vector regression model that predicted trait autism, empathy, and alexithymia. Results showed that less leftward asymmetry of CSA in the gyrus rectus (a subregion of the orbitofrontal cortex) predicted more difficulties in social functioning, as well as reduced cognitive empathy and elevated trait alexithymia. Meta-analytic decoding of the left gyrus rectus annotated functional items related to social cognition. Furthermore, the link between gyrus rectus asymmetry and social difficulties was accounted by trait alexithymia and cognitive empathy. These results suggest that gyrus rectus asymmetry could be a shared neural correlate among trait alexithymia, cognitive empathy, and social functioning in neurotypical adults. Left-right asymmetry of gyrus rectus influenced social functioning by affecting the cognitive processes of emotions in the self and others. Interventions that increase leftward asymmetry of the gyrus rectus might improve social functioning for individuals with ASD.

[Analysis of respiratory syncytial virus infection in hospitalized children with acute lower respiratory tract infection in China from 2017 to 2020]

Objective: To understand the detection rate, epidemic pattern of respiratory syncytial virus (RSV) in hospitalized children with acute lower respiratory tract infection (ALRTI) in China. Methods: From June 2017 to March 2020, a prospective multi-center study on the viral aetiology among hospitalized children with ALRTI was conducted in six pediatrics hospital of North China, Northeast, Northwest, South China, Southeast, and Southwest China. A total of 2 839 hospitalized children with ALRTI were enrolled, and the respiratory specimens were collected from these cases. A multiplex real-time RT-PCR assay were employed to screen the respiratory viruses, and the molecular epidemiological and clinical characteristics of children infected with RSV were analyzed. Results: The positve rate of RSV was 18.6% (528/2 839), and the positive rate of RSV in different regions ranged from 5.5% to 44.3%. The positive rate of RSV in male was higher than that in female (20.2% vs 16.3%), and there was a significant statistically difference between two groups (χ2=6.74, P=0.009). The positive rate of RSV among children under 5 years old was higher than that among children older than 5 years old (22.3% vs 4.5%), and there was a significant statistically difference between two groups (χ2=97.98,P<0.001). The positive rate of RSV among the <6 months age group was higher than that of other age groups (all P<0.05). During January 2018 and December 2019, RSV was detected in almost all through the year, and showed peaks in winter and spring. RSV-positive cases accounted for 17.0% (46/270) among children with severe pneumonia, including 36 cases infected with RSV alone. Conclusion: RSV is an important viral pathogen in children under 5 years old with ALRTI in China. The virus can be detected almost all through the year and reached the peak in winter and spring. RSV could lead to severe pneumonia in children and caused huge threaten to children's health.

[Effect of China Children's Asthma Action Plan on exercise in school-age children with bronchial asthma]

Objective: To investigate the effect of China Children's Asthma Action Plan (CCAAP) on the exercise status of school-age children with asthma. Methods: We included 400 school-age asthmatic children as research objects from CCAAP asthma management platform of the Affiliated Hospital of Qingdao University during March 1, 2018 to February 28, 2021 by simple random sampling method. The questionnaires of basic information and international physical activity were applied through WeChat or face to face investigation to collect the basic information and exercise status of the object. There were 346 valid questionnaires included in the study to compare the differences in exercise status and incidence of exercise-related asthma-like symptoms between the good and poor CCAAP application groups. Results: There were 232 (67.05%) and 114 (32.95%) cases in good and poor CCAAP application group, respectively. Age, female proportion and BMI of good CCAAP application group were (8±2) years, 47.0% (109/232) and (19.79±2.32) kg/m², respectively, no statistic difference comparing to poor CCAAP application group [(8±2) years, 46.5% (53/114) and (19.87±2.43) kg/m², respectively] (all P values>0.05). In good CCAAP application group, 30.18% (70/232) achieved the standard of moderate (high) intensity exercise per day, no statistic difference comparing to poor CCAAP application group [29.82% (34/112)] (P=0.947); 31.90% (74/232) participated in high-intensity exercise per week, higher than that of poor CCAAP application group [17.54% (20/112)] (P=0.005); incidence of exercise-related asthma-like symptoms was 19.83% (46/232), lower than that of poor CCAAP application group [29.82% (34/112)] (P=0.038). Conclusion: CCAAP promotes the exercise of school-age children with asthma.

Effects of High-Definition Transcranial Direct Current Stimulation Over the Primary Motor Cortex on Cold Pain Sensitivity Among Healthy Adults

Some clinical studies have shown promising effects of transcranial direct current stimulation (tDCS) over the primary motor cortex (M1) on pain relief. Nevertheless, a few studies reported no significant analgesic effects of tDCS, likely due to the complexity of clinical pain conditions. Human experimental pain models that utilize indices of pain in response to well-controlled noxious stimuli can avoid many confounds that are present in the clinical data. This study aimed to investigate the effects of high-definition tDCS (HD-tDCS) stimulation over M1 on sensitivity to experimental pain and assess whether these effects could be influenced by the pain-related cognitions and emotions. A randomized, double-blinded, crossover, and sham-controlled design was adopted. A total of 28 healthy participants received anodal, cathodal, or sham HD-tDCS over M1 (1 mA for 20 min) in different sessions, in which montage has the advantage of producing more focal stimulation. Using a cold pressor test, several indices reflecting the sensitivity to cold pain were measured immediately after HD-tDCS stimulation, such as cold pain threshold and tolerance and cold pain intensity and unpleasantness ratings. Results showed that only anodal HD-tDCS significantly increased cold pain threshold when compared with sham stimulation. Neither anodal nor cathodal HD-tDCS showed significant analgesic effects on cold pain tolerance, pain intensity, and unpleasantness ratings. Correlation analysis revealed that individuals that a had lower level of attentional bias to negative information benefited more from attenuating pain intensity rating induced by anodal HD-tDCS. Therefore, single-session anodal HD-tDCS modulates the sensory-discriminative aspect of pain perception as indexed by the increased pain threshold. In addition, the modulating effects of HD-tDCS on attenuating pain intensity to suprathreshold pain could be influenced by the participant’s negative attentional bias, which deserves to be taken into consideration in the clinical applications.

Dietary chitooligosaccharide supplementation alleviates intestinal barrier damage, and oxidative and immunological stress in lipopolysaccharide-challenged laying hens

This study aimed to investigate the effects of chitooligosaccharide (COS) on intestinal barrier, antioxidant capacity, and immunity of lipopolysaccharide (LPS)-challenged laying hens. A total of 360 Hy-line Brown laying hens (80-wk-old) were randomly divided into 5 groups with 6 replicates of 12 birds. Hens were fed a corn-soybean meal basal diet supplemented with different COS levels (0; 5; 10; 15; 20 mg/kg) for 8 wk. The results showed that 15 mg/kg COS administration elevated albumen height and Haugh unit (P < 0.05), and numerically optimized productive performance (P > 0.05), therefore, the dosage of 15 mg/kg was chosen for the subsequent experiment. Thereafter, 12 birds from non-supplemented group were randomly selected and assigned into 2 groups, and birds in each group were administered (1.5 mg/kg BW, i.p.) with saline (control group) or LPS (challenge group). Another 6 hens from 15 mg/kg COS-supplemented group were selected and injected with LPS in the same way. Compared with the control group, LPS-challenged birds exhibited elevated circulating diamine oxidase activity, and reduced jejunal villus height and ratio of villus height to crypt depth, and these indices were reversed to control levels by COS (P < 0.05). Also, LPS increased malondialdehyde accumulation and reduced several antioxidant enzyme activities in the intestinal mucosa (P < 0.05). Additionally, LPS increased jejunal secretory IgA and interferon-γ (IFN-γ), and ileal secretory IgA, IgM, and interleukin-1β (IL-1β) concentrations, whereas COS reduced jejunal IFN-γ and IL-1β, and ileal IgM levels (P < 0.05). Moreover, LPS down-regulated mRNA abundance of jejunal occludin and claudin 2, and upregulated expression of jejunal nuclear factor erythroid-2 related factor 2, superoxide dismutase 1, and IFN-γ as well as ileal IL-1β (P < 0.05). Besides, COS increased jejunal occludin and ileal claudin 2, nuclear factor erythroid-2 related factor 2, and heme oxygenase-1 expression, and decreased jejunal IFN-γ and IL-1β abundance (P < 0.05). These results suggested that COS could alleviate LPS-induced intestinal barrier impairment, and oxidative and immunological stress in laying hens.

Multi-Learner Based Deep Meta-Learning for Few-Shot Medical Image Classification

Few-shot learning (FSL) is promising in the field of medical image analysis due to high cost of establishing high-quality medical datasets. Many FSL approaches have been proposed in natural image scenes. However, present FSL methods are rarely evaluated on medical images and the FSL technology applicable to medical scenarios need to be further developed. Meta-learning has supplied an optional framework to address the challenging FSL setting. In this paper, we propose a novel multi-learner based FSL method for multiple medical image classification tasks, combining meta-learning with transfer-learning and metric-learning. Our designed model is composed of three learners, including auto-encoder, metric-learner and task-learner. In transfer-learning, all the learners are trained on the base classes. In the ensuing meta-learning, we leverage multiple novel tasks to fine-tune the metric-learner and task-learner in order to fast adapt to unseen tasks. Moreover, to further boost the learning efficiency of our model, we devised real-time data augmentation and dynamic Gaussian disturbance soft label (GDSL) scheme as effective generalization strategies of few-shot classification tasks. We have conducted experiments for three-class few-shot classification tasks on three newly-built challenging medical benchmarks, BLOOD, PATH and CHEST. Extensive comparisons to related works validated that our method achieved top performance both on homogeneous medical datasets and cross-domain datasets.