Objective Most SARS‐CoV‐2‐infected individuals never require hospitalization. However, some develop prolonged symptoms. We sought to characterize the spectrum of neurologic manifestations in non‐hospitalized Covid‐19 “long haulers”. Methods This is a prospective study of the first 100 consecutive patients (50 SARS‐CoV‐2 laboratory‐positive (SARS‐CoV‐2+) and 50 laboratory‐negative (SARS‐CoV‐2‐) individuals) presenting to our Neuro‐Covid‐19 clinic between May and November 2020. Due to early pandemic testing limitations, patients were included if they met Infectious Diseases Society of America symptoms of Covid‐19, were never hospitalized for pneumonia or hypoxemia, and had neurologic symptoms lasting over 6 weeks. We recorded the frequency of neurologic symptoms and analyzed patient‐reported quality of life measures and standardized cognitive assessments. Results Mean age was 43.2 ± 11.3 years, 70% were female, and 48% were evaluated in televisits. The most frequent comorbidities were depression/anxiety (42%) and autoimmune disease (16%). The main neurologic manifestations were: “brain fog” (81%), headache (68%), numbness/tingling (60%), dysgeusia (59%), anosmia (55%), and myalgias (55%), with only anosmia being more frequent in SARS‐CoV‐2+ than SARS‐CoV‐2‐ patients (37/50 [74%] vs. 18/50 [36%]; p < 0.001). Moreover, 85% also experienced fatigue. There was no correlation between time from disease onset and subjective impression of recovery. Both groups exhibited impaired quality of life in cognitive and fatigue domains. SARS‐CoV‐2+ patients performed worse in attention and working memory cognitive tasks compared to a demographic‐matched US population (T‐score 41.5 [37, 48.25] and 43 [37.5, 48.75], respectively; both p < 0.01). Interpretation Non‐hospitalized Covid‐19 “long haulers” experience prominent and persistent “brain fog” and fatigue that affect their cognition and quality of life.

Novel methods to analyze the tumor microenvironment (TME) are urgently needed to stratify melanoma patients for adjuvant immunotherapy. Tumor-infiltrating lymphocyte (TIL) analysis, by conventional pathologic methods, is predictive but is insufficiently precise for clinical application. Quantitative multiplex immunofluorescence (qmIF) allows for evaluation of the TME using multiparameter phenotyping, tissue segmentation, and quantitative spatial analysis (qSA). Given that CD3CD8 cytotoxic lymphocytes (CTLs) promote antitumor immunity, whereas CD68 macrophages impair immunity, we hypothesized that quantification and spatial analysis of macrophages and CTLs would correlate with clinical outcome. We applied qmIF to 104 primary stage II to III melanoma tumors and found that CTLs were closer in proximity to activated (CD68HLA-DR) macrophages than nonactivated (CD68HLA-DR) macrophages ( < 0.0001). CTLs were further in proximity from proliferating SOX10 melanoma cells than nonproliferating ones ( < 0.0001). In 64 patients with known cause of death, we found that high CTL and low macrophage density in the stroma ( = 0.0038 and = 0.0006, respectively) correlated with disease-specific survival (DSS), but the correlation was less significant for CTL and macrophage density in the tumor ( = 0.0147 and = 0.0426, respectively). DSS correlation was strongest for stromal HLA-DR CTLs ( = 0.0005). CTL distance to HLA-DR macrophages associated with poor DSS ( = 0.0016), whereas distance to Ki67 tumor cells associated inversely with DSS ( = 0.0006). A low CTL/macrophage ratio in the stroma conferred a hazard ratio (HR) of 3.719 for death from melanoma and correlated with shortened overall survival (OS) in the complete 104 patient cohort by Cox analysis ( = 0.009) and merits further development as a biomarker for clinical application. .

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Extreme heat stress-induced gastrointestinal injury and dysfunction may occur during summer. We investigated possible mechanisms of heat stress-induced damage in the small intestine using male Sprague-Dawley rats subjected to 2 h of heat stress (40 °C, 60% relative humidity) daily for 10 consecutive days. Rats were killed at specific times immediately following heat treatment to determine: morphological changes by optical and electron microscopy; intestinal permeability using fluorescein isothiocyanate-dextran; production of reactive oxygen species (ROS), malondialdehyde (MDA), and activities of superoxide-dismutase and glutathione-peroxidase by specific assays; phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun N-terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK) by immunocytochemistry and western-blot analysis. The rat intestinal epithelial cell line (IEC-6) and specific MAPK inhibitors were used for in vitro investigation of effects of activation of MAPKs by heat stress. Heat stress caused marked morphological damage to the small intestine and significantly increased intestinal permeability. Heat stress increased ROS and MDA production, and significantly reduced anti-oxidase activity. MAPK activity in small intestine was increased by heat stress. In vitro, heat stress caused damage and apoptosis in IEC-6 cells; inhibition of ERK1/2 activation (by U0126) exacerbated these effects, which were attenuated by inhibition of JNK (by SP600125) and p38 (by SB203580) activation. Hence, heat stress caused severe small intestine injury, increased oxidative stress, and activated MAPK signaling pathways. The in vitro studies indicated that ERK1/2 activation is anti-apoptotic, and JNK and p38 activation are pro-apoptotic in heat stressed intestinal epithelial cells.

Cell membrane chromatography (CMC) is an ideal method for screening potential active components acting on target cell membranes from a complex system, such as herbal medicines. But due to the decay and falling-off of membranes, the CMC column suffers from short life span and low reproducibility. This has greatly limited the application of this model, especially when the cell materials are hard to obtain. To solve this problem, a novel type of (3-aminopropyl)triethoxysilane (APTES)-decorated silica gel was employed. The silica gel was decorated with aldehydes with the help of APTES, which react with the amino groups on cell membranes to form a covalent bond. In this way, cell membranes were immobilized on the surface of silica gel, so it is not easy for membranes to fall off. According to our investigation, the column life of the APTES-decorated group was prolonged to more than 12 days, while the control group showed a sharp decline in column efficiency in the first 3 days. To verify this model, a novel APTES-decorated HepG2 cancer stem cell membrane chromatography (CSCMC) was established and applied in a comprehensive two-dimensional chromatographic system to screen potential active components in Salvia miltiorrhiza. As a result, tanshinone IIA, cryptotanshinone, and dihydrotanshinone I were retained on this model and proved to be effective on HepG2 cancer stem cells by the following cell proliferation and apoptosis assay, with IC of 10.30 μM, 17.85 μM, and 2.53 μM, respectively. This improvement of CMC can significantly prolong its column life span and broaden the range of its application, which is very suitable for making invaluable or hard-to-obtain cell materials, such as stem cells, for specific drug screening.

Antioxidant peptides obtained from snakehead (Channa argus) soup (SHS) after simulated gastrointestinal (GI) digestion were separated, identified and characterized. Results showed that the fraction with MW < 3 kDa had the highest antioxidant capacity. Four novel antioxidant peptides were identified after RP-HPLC and UPLC-MS/MS. PGMLGGSPPGLLGGSPP and SDGSNIHFPN had the highest DPPH radical scavenging activity (IC50 = 1.39 mM) and Fe 2+ chelating ability (IC50 = 4.60 mM), respectively. Structures in silico for IVLPDEGK, PGMLGGSPPGLLGGSPP and SDGSNIHFPN suggest that at least one β-turn and/or α-helix, are associated with antioxidant activity. Moreover, our results showed that these three peptides docked with a recombinant Kelch-like ECH-associated protein 1 (Keap1) with a binding score greater than TX6, a good ligand of Keap1. The cell viability assay also showed significant cytoprotective effects against H2O2-induced cellular oxidative damage. This information implies that antioxidant mechanisms of novel peptides occurred via activation of cellular anti-oxidation Keap1-Nrf2 signaling pathway.

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