Mapping the risk factors, pathogens, and antibiotic of pharyngocutaneous fistula in patients after neck open surgery.

PURPOSE: Current literature lacks consensus on risk factors for pharyngocutaneous fistula (PCF), and empirical antibiotic guidelines for PCF are limited. The aim of this study was to reduce the incidence of PCF and improve antibiotic treatment efficacy for patients with PCF after open neck surgery by analyzing their clinical characteristics, pathogenic bacteria, and antibiotic susceptibility. METHODS: This study was a 13-year single-center retrospective cohort study, including 699 patients who underwent open neck surgery for laryngeal and hypopharyngeal cancer. Univariate and multivariate logistic regression analyses were conducted to identify the risk factors associated with the occurrence of PCF after surgery. The microbial species causing PCF were analyzed, and the antibiotic sensitivity of the top three pathogens was assessed. Venn diagrams were used to illustrate the antibiotics that exhibited 100% sensitivity against all three identified pathogens. RESULTS: The incidence of PCF after open neck surgery was 8%. Logistic univariate and multivariate analyses revealed that flap reconstruction (OR = 3.62, 95% CI [2.02-6.52]), history of preoperative radiotherapy (OR = 2.01, 95% CI [1.31-2.73]), significant postoperative bleeding (OR = 1.79, 95% CI [1.11-2.69]), and history of diabetes (OR = 1.34, 95% CI [1.29-2.46]) were significantly associated with PCF occurrence. Among the 38 cases of PCF patients, the top three identified pathogens were Pseudomonas aeruginosa, Escherichia coli, and Enterobacter cloacae. The antibiotics cefepime, meropenem, ticarcillin/clavulanic acid, and cefoperazone/sulbactam showed 100% sensitivity against these top three pathogens. CONCLUSION: Special attention should be given to patients undergoing open neck surgery, especially those with intraoperative flap reconstruction, a history of preoperative radiotherapy, postoperative bleeding, or diabetes. Strengthening monitoring and care is crucial in preventing the occurrence of PCF. According to antibiotic usage guidelines and considering the distribution of pathogens in PCF patients, empirical antibiotic treatment with cefoperazone/sulbactam or ticarcillin/clavulanic acid is recommended prior to obtaining susceptibility test results.

Variations in serum low-density lipoprotein and sST2 among heart failure patients with different ejection fraction groups and their clinical significance.

OBJECTIVE: This study aimed to examine the changes in serum Low Density Lipoprotein Cholesterol (LDL-C) and Soluble Growth Stimulating Expressed Gene 2 Protein (sST2) among Heart Failure (HF) patients with varying ejection fractions and their clinical significance, providing a reference for the clinical assessment of HF severity. METHODS: A total of 238 HF patients treated in our hospital's cardiology department from September 2019 to December 2021 were selected; 68 patients hospitalized in the same period were selected as the control group. General information, LDL-C and echocardiographic results of admitted patients were collected. According to LVEF results and the latest European Society of Cardiology standards in 2021, HF patients were categorized into those with HFpEF (n = 95), HFmrEF (n = 60), and HFrEF (n = 83). Meanwhile, venous blood was collected to determine sST2 and NT-proBNP to compare and analyze the changes and clinical significance of sST2 and LDL-C across the groups. RESULTS: Compared to the control group, the HF group showed significant differences in age, gender, heart rate, smoking history, history of atrial fibrillation, history of diabetes, LVEDD, LVEF, sST2, and NT-proBNP levels (P < .05), but not in LDL-C levels. Significant differences (P < .05) were also found among the 3 HF groups in terms of age, gender, history of atrial fibrillation, LVEDD, LVEF, LDL-C, sST2, and NT-proBNP levels, with an increase in LVEDD, LDL-C, sST2, and NT-proBNP values as the ejection fraction decreased. ROC curve analysis indicated that the area under the curve (AUC) for sST2 in diagnosing HF was 0.915 (P < .05), with an optimal cutoff value of 23.71 ng/mL, a sensitivity of 76.5%, and a specificity of 95.6%; LDL-C was not a significant diagnostic marker for HF (P > .05). Coronary artery disease, NT-proBNP, and sST2 were identified as risk factors for HF. With each unit increase in coronary artery disease, the risk of HF increased by 36.3%; for NT-proBNP, the risk increased by 1.3% per unit; and for sST2, it increased by 18.3% per unit. CONCLUSION: As the ejection fraction decreases in HF patients, serum sST2 and LDL-C values progressively increase, which is clinically significant for predicting the severity of HF. sST2 is an independent risk factor for HF and can enhance the diagnostic accuracy for HF.

Targeting CD38/ ADP-ribosyl cyclase as a novel therapeutic strategy for identification of three potent agonists for leukopenia treatment.

Leukopenia is the most common side effect of chemotherapy and radiotherapy. It potentially deteriorates into a life-threatening complication in cancer patients. Despite several agents being approved for clinical administration, there are still high incidences of pathogen-related disease due to a lack of functional immune cells. ADP-ribosyl cyclase of CD38 displays a regulatory effect on leukopoiesis and the immune system. To explore whether the ADP-ribosyl cyclase was a potential therapeutic target of leukopenia. We established a drug screening model based on an ADP-ribosyl cyclase-based pharmacophore generation algorithm and discovered three novel ADP-ribosyl cyclase agonists: ziyuglycoside II (ZGSII), brevifolincarboxylic acid (BA), and 3,4-dihydroxy-5-methoxybenzoic acid (DMA). Then, in vitro experiments demonstrated that these three natural compounds significantly promoted myeloid differentiation and antibacterial activity in NB4 cells. In vivo, experiments confirmed that the compounds also stimulated the recovery of leukocytes in irradiation-induced mice and zebrafish. The mechanism was investigated by network pharmacology, and the top 12 biological processes and the top 20 signaling pathways were obtained by intersecting target genes among ZGSII, BA, DMA, and leukopenia. The potential signaling molecules involved were further explored through experiments. Finally, the ADP-ribosyl cyclase agonists (ZGSII, BA, and DMA) has been found to regenerate microbicidal myeloid cells to effectively ameliorate leukopenia-associated infection by activating CD38/ADP-ribosyl cyclase-Ca2+-NFAT. In summary, this study constructs a drug screening model to discover active compounds against leukopenia, reveals the critical roles of ADP-ribosyl cyclase in promoting myeloid differentiation and the immune response, and provides a promising strategy for the treatment of radiation-induced leukopenia.

Discovery of benzodiazepine derivatives as a new class of covalent inhibitors of SARS-CoV-2 main protease.

The COVID-19 pandemic has caused people immense suffering all over the world. Although the World Health Organization (WHO) has announced the end of the pandemic, the sporadic virus epidemic is still ongoing and may exist permanently. Effective antivirals against SARS-CoV-2 are important to deal with the long-term threat. The main protease (Mpro) is a crucial target for drug development due to its role in the process of virus's replication and transcription. Herein, we report benzodiazepine derivatives as a new class of Mpro inhibitors. Structure-activity relationship (SAR) studies led to the discovery of the most active compound, methyl 10-(2-chloroacetyl)-1-oxo-11-(4-(trifluoromethyl)phenyl)-2,3,4,5,10,11-hexahydro-1H-dibenzo[b,e][1,4]-diazepine-7-carboxylate (11a), which shows an IC50 value of 0.180 ± 0.004 µM. The X-ray crystal structure shows that 11a covalently binds to Mpro. Collectively, we have obtained a new small molecule inhibitor targeting Mpro, which can serve as a lead compound for subsequent drug discovery against SARS-CoV-2.

Promising remedies for cardiovascular disease: Natural polyphenol ellagic acid and its metabolite urolithins.

BACKGROUND: Cardiovascular disease (CVD) is a significant worldwide factor contributing to human fatality and morbidity. With the increase of incidence rates, it is of concern that there is a lack of current therapeutic alternatives because of multiple side effects. Ellagic acid (EA), the natural polyphenol (C14H6O8), is abundant in pomegranates, berries, and nuts. EA and its intestinal microflora metabolite, urolithins, have recently attracted much attention as a potential novel "medicine" because of their wide pharmacological properties. PURPOSE: This study aimed to critically analyze available literature to summarize the beneficial effects of EA and urolithins, and highlights their druggability and therapeutic potential in various CVDs. METHODS: We systematically studied research and review articles between 1984 and 2022 available on various databases to obtain the data on EA and urolithins with no language restriction. Their cardiovascular protective activities, underlying mechanism, and druggability were highlighted and discussed comprehensively. RESULTS: We found that EA and urolithins may exert preventive and curative effects on CVD with negligible side effects and possibly regulate lipid metabolism imbalance, pro-inflammatory factor production, vascular smooth muscle cell proliferation, cardiomyocyte apoptosis, endothelial cell dysfunction, and Ca2+ intake and release. Potentially, this may lead to the prevention and amelioration of atherosclerosis, hypertension, myocardial infarction, cardiac fibrosis, cardiomyopathy, cardiac arrhythmias, and cardiotoxicities in vivo. Several molecules and signaling pathways are associated with their therapeutic actions, including phosphatidylinositol 3-kinase/protein kinase B, mitogen-activated protein kinase, NF-κB, nuclear factor erythroid-2 related factor 2, sirtuin1, miRNA, and extracellular signal-regulated kinase 1/2. CONCLUSION: In vitro and in vivo studies shows that EA and urolithins could be used as valid candidates for early prevention and effective therapeutic strategies for various CVDs.

Pharmacological inhibition of LSD1 suppresses growth of hepatocellular carcinoma by inducing GADD45B.

Lysine-specific histone demethylase 1 (LSD1) is an attractive target for malignancies therapy. Nevertheless, its role in hepatocellular carcinoma (HCC) progression and the potential of its inhibitor in HCC therapy remains unclear. Here, we show that LSD1 overexpression in human HCC tissues is associated with HCC progression and poor patient survival. ZY0511, a highly selective and potent inhibitor of LSD1, suppressed human HCC cell proliferation in vitro and tumor growth in cell-derived and patient-derived HCC xenograft models in vivo. Mechanistically, ZY0511 induced mRNA expression of growth arrest and DNA damage-inducible gene 45beta (GADD45B) by inducing histone H3 at lysine 4 (H3K4) methylation at the promoter of GADD45B, a novel target gene of LSD1. In human HCC tissues, LSD1 level was correlated with a decreased level of GADD45B, which was associated with HCC progression and predicted poor patient survival. Moreover, co-administration of ZY0511 and DTP3, which specifically enhanced the pro-apoptotic effect of GADD45B, effectively inhibited HCC cell proliferation both in vitro and in vivo. Collectively, our study revealed the potential value of LSD1 as a promising target of HCC therapy. ZY0511 is a promising candidate for HCC therapy through upregulating GADD45B, thereby providing a novel combinatorial strategy for treating HCC.

Surgical Treatment for Cutaneous Mycobacterium abscessus Infection Caused by Injections of Hyaluronic Acid.

Background: Facial injection has become popular in aesthetic dermatology. Although injections of these tissue fillers are considered a low-risk procedure, they are not without potentially significant drawbacks. Case Presentation: We would like to report a case about cutaneous Mycobacterium abscessus infection after facial injection of hyaluronic acid in China, which obtained satisfactory clinical efficacy by drainage and surgical excision. Conclusion: Biological techniques are useful in the diagnosis of cutaneous M. abscessus infection. Surgical excision of skin lesion is effective for cutaneous M. abscessus infection.

Curcumin-Loaded Platelet Membrane Bioinspired Chitosan-Modified Liposome for Effective Cancer Therapy.

Cancer is a serious threat to human health, and chemotherapy for cancer is limited by severe side effects. Curcumin (CUR) is a commonly used natural product for antitumor treatment without safety concerns. However, low bioavailability and poor tumor accumulation are great obstacles for its clinical application. Our previous research has demonstrated that platelet membrane-camouflaged nanoparticles can efficiently ameliorate the in vivo kinetic characteristics and enhance the tumor affinity of payloads. Nevertheless, the antitumor efficiency of this formulation still needs to be thoroughly investigated, and its drug release behavior is limited. Herein, CUR-loaded platelet membrane bioinspired chitosan-modified liposome (PCLP-CUR) was constructed to improve CUR release. PCLP-CUR was shown to have long retention time, improved bioavailability, strong tumor targeting capacity and effective cellular uptake. The incorporation of chitosan enabled PCLP-CUR to release cargoes quickly under mild acidic tumor conditions, leading to more complete drug release and favoring subsequent treatment. Both in vitro and in vivo investigations showed that PCLP-CUR could significantly enhance the anticancer efficacy of CUR with minimal side effects through biomimetic membrane and chitosan modification. In summary, this developed delivery system can provide a promising strategy for tumor-targeting therapy and phytochemical delivery.

A comprehensive comparison of medication strategies for platinum-sensitive recurrent ovarian cancer: A Bayesian network meta-analysis.

Background: The Platinum-based combination has been proven to have an outstanding effect on patients with platinum-sensitive recurrent ovarian cancer (PSROC), but the best scientific combination has not been established yet. The present study is aimed to seek the best treatment plan for PSROC. Methods: We did a systematic review and Bayesian network meta-analysis, during which lite before March 2022 were retrieved on PubMed, Embase, Web of Science, and Cochrane Central Registry of Controlled databases. We included randomized controlled clinical trials comparing chemotherapy combinations with other treatments for patients with PSROC. The important outcomes concerned were progression-free survival (PFS) (the primary outcome), overall survival (OS), objective response rate (ORR), adverse events (AEs), and AEs-related discontinuation. All outcomes were ranked according to the surface under the cumulative ranking curve. Results: 26 trials involving 10441 patients were retrieved in this study. For the initial treatment of PSROC, carboplatin plus pegylated liposomal doxorubicin (PLD) plus bevacizumab had the best PFS [hazard ratio (HR) 0.59, 95% credible interval (CI) 0.51-0.68]; Carboplatin plus paclitaxel plus bevacizumab resulted in the best OS (HR 1.22, 95% CI 1.09-1.35) and ORR [odds ratio (OR) 1.22, 95% CI 1.09-1.35]. For the maintenance therapy in PSROC, poly (ADP-ribose) polymerase inhibitors (PARPi) following platinum-based chemotherapy provided the best PFS (HR 0.64, 95% CI 0.61-0.68), the highest frequency of adverse events of grade three or higher (OR 0.18, 95% CI 0.07-0.44) but the treatment discontinuation was generally low. Subgroup analysis suggested that trabectedin plus PLD was comparable to single platinum in prolonging PFS in the platinum-free interval (6-12 months). Conclusion: Both platinum-based chemotherapy plus PARPi and platinum-based chemotherapy plus bevacizumab had higher survival benefits than other treatments in PSROC. Trabectedin plus PLD might be a potential alternative treatment strategy for the partially platinum-sensitive subpopulation with intolerance to platinum. Systematic Review Registration: [https://www.crd.york.ac.uk/prospero/display_record.php?], identifier [CRD42022326573].

Sodium butyrate attenuated diet-induced obesity, insulin resistance and inflammation partly by promoting fat thermogenesis via intro-adipose sympathetic innervation.

Emerging evidence suggests that butyrate, a short-chain fatty acid, may have beneficial effects on obesity and its associated metabolic comorbidities, but the related molecular mechanism is largely unknown. This study aims to investigate the role of butyrate in diet-induced obesity and metabolic disorders and the relevant regulatory mechanisms. Here, dietary supplementation with Sodium butyrate (NaB) was carried out in mice fed with a high-fat diet (HFD) or chow diet. At week 14, mice on HFD displayed an obese phenotype and down-regulated expression of thermogenic regulators including Ucp-1 and Pgc-1α in adipose tissue. Excitingly, NaB add-on treatment abolished these detrimental effects. Moreover, the obesity-induced insulin resistance, inflammation, fatty liver, and intestinal dysfunction were also attenuated by NaB administration. Mechanistically, NaB can promote fat thermogenesis via the increased local sympathetic innervation of adipose tissue, and blocking the ß3-adrenergic signaling pathway by 6-hydroxydopamine abolished NaB-induced thermogenesis. Our study reveals a potential pharmacological target for NaB to combat obesity and metabolic disorders.

Enoxacin ameliorates polycystic ovary syndrome by promoting the browning of white adipose tissue and restoring gut dysbiosis.

Polycystic ovary syndrome (PCOS) is a complex endocrine disorder syndrome characterized by polycystic ovary, ovulation disorder and hyperandrogenemia, and is often accompanied by metabolic disorders. Enoxacin has been reported to protect against diet-induced obesity and insulin resistance by promoting fat thermogenesis. However, the function of enoxacin in PCOS remains unknown. This study aimed to investigate the impact of the enoxacin on the regulation of PCOS mouse model induced by dehydroepiandrosterone (DHEA). Here, we found that reproductive endocrine disorder, glucose intolerance, and ovarian dysfunction in PCOS mice induced by DHEA were attenuated by enoxacin treatment. Mechanistically, we identified that enoxacin can promote white fat browning and improve metabolic disorders, thus ameliorating DHEA-induced reproductive dysfunction. Moreover, these beneficial effects might be associated with the restoration of gut dysbiosis. These findings provide a novel therapeutic target for enoxacin in the treatment of PCOS.

Neuritin Promotes Bone Marrow-Derived Mesenchymal Stem Cell Migration to Treat Diabetic Peripheral Neuropathy.

The purpose of this study is to explore the effect and mechanism of neuritin overexpression in the bone marrow on peripheral neuropathy in type 2 diabetic (db/db) mice. We analyzed the impact of bone marrow neuritin overexpression on diabetic peripheral neuropathy and migration of bone marrow mesenchymal stem cells in db/db mice. Antagonists were used to inhibit the stromal cell-derived factor (SDF)-1α/C-X-C chemokine receptor type 4 (CXCR4)-phosphoinositide 3-kinase (PI3K)/Akt signaling pathway in primary cultured bone marrow mesenchymal stem cells. Immunofluorescence, transmission electron microscopy, Oil Red O staining, and transwell migration assays were used. Bone marrow-specific overexpression of neuritin in db/db mice was successfully established. Overexpression of neuritin in the bone marrow ameliorated hyperglycemia, prevented diabetic peripheral neuropathy, protected the ultrastructure of the sciatic nerve and intra-epidermal nerve fiber density, and promoted Schwann cell proliferation and remyelination in the sciatic nerve. Moreover, it ameliorated fat accumulation, adipocyte number, and vascular and nerve densities; decreased glutamate content in serum and bone marrow; restored gradient SDF-1α contents between bone marrow, blood, and sciatic nerve; and promoted impaired diabetic bone marrow mesenchymal stem cell migration. Neuritin improves bone marrow mesenchymal stem cell migration via the SDF-1α/CXCR4-PI3K/Akt signaling pathway in vitro. Overexpression of neuritin in the bone marrow can locally ameliorate neuropathy in the bone marrow. This improves the migration capability of bone marrow mesenchymal stem cells and repairs diabetic peripheral neuropathy, at least partly by activating the PI3K/Akt pathway through the SDF-1α/CXCR4 axis.

Duck hepatitis A virus type 1 mediates cell cycle arrest in the S phase.

BACKGROUND: Duck hepatitis A virus type 1 (DHAV-1) is one of the most serious pathogens endangering the duck industry. However, there are few studies on the regulation of the cell cycle by DHAV-1. METHODS: In this study, flow cytometry was applied to analyze the effect of DHAV-1 infection on the cell cycle of duck embryo fibroblasts (DEFs). Subsequently, we analyzed the effects of cell cycle phases on DHAV-1 replication by real-time reverse transcriptase quantitative PCR (real-time RT-qPCR). RESULTS: Flow cytometry data analysis found that DEFs in the S phase increased by 25.85% and 54.21% at 24 h and 48 h after DHAV-1 infection, respectively. The levels of viral RNA detected by real-time RT-qPCR were higher in the DEFs with synchronization in the S phase or G0/G1 phase than in the control group. However, there was no difference in viral copy number between the G2/M phase arrest and control groups. In addition, non-structural protein 3D of DHAV-1 significantly increased cells in the S phase, indicating that 3D protein is one of the reasons for the cell cycle arrest in the S phase. CONCLUSIONS: In summary, DHAV-1 infection induces the cell cycle arrest of DEFs in the S phase. Both S phase and G0/G1 phase synchronization facilitate the replication of DHAV-1, and 3D protein is one of the reasons for the S phase arrest.

Ultra-parallel label-free optophysiology of neural activity.

The electrical activity of neurons has a spatiotemporal footprint that spans three orders of magnitude. Traditional electrophysiology lacks the spatial throughput to image the activity of an entire neural network; besides, labeled optical imaging using voltage-sensitive dyes and tracking Ca2+ ion dynamics lack the versatility and speed to capture fast-spiking activity, respectively. We present a label-free optical imaging technique to image the changes to the optical path length and the local birefringence caused by neural activity, at 4,000 Hz, across a 200 × 200 µm2 region, and with micron-scale spatial resolution and 300-pm displacement sensitivity using Superfast Polarization-sensitive Off-axis Full-field Optical Coherence Microscopy (SPoOF OCM). The undulations in the optical responses from mammalian neuronal activity were matched with field-potential electrophysiology measurements and validated with channel blockers. By directly tracking the widefield neural activity at millisecond timescales and micrometer resolution, SPoOF OCM provides a framework to progress from low-throughput electrophysiology to high-throughput ultra-parallel label-free optophysiology.

A Comprehensive Review of Genus Sanguisorba: Traditional Uses, Chemical Constituents and Medical Applications.

Genus Sanguisorba (family: Rosaceae) comprises nearly 148 species, distributed widely across the temperate and subtropical regions of the Northern Hemisphere. Sanguisorba officinalis L. (S. officinalis) has been used as a hemostatic and scald treating medicine in China for a long time. Numerous studies have demonstrated that plant extracts or monomers from S. officinalis exhibit several pharmacological effects, such as anti-cancer, anti-virus, anti-inflammation, anti-bacteria, neuroprotective and hepatoprotective effects. The other species of genus Sanguisorba are also being studied by researchers worldwide. Sanguisorba minor Scop. (S. minor), as an edible wild plant, is a common ingredient of the Mediterranean diet, and its young shoots and leaves are often mixed with traditional vegetables and consumed as salad. Reports on genus Sanguisorba available in the current literature were collected from Google Scholar, Web of Science, Springer, and PubMed. The Plant List (http://www.theplantlist.org./tpl1.1/search?q=Sanguisorba), International Plant Name Index (https://www.ipni.org/?q=Sanguisorba) and Kew Botanical Garden (http://powo.science.kew.org/) were used for obtaining the scientific names and information on the subspecies and cultivars. In recent years, several in vivo and in vitro experiments have been conducted to reveal the active components and effective monomers of S. officinalis and S. minor. To date, more than 270 compounds have been isolated and identified so far from the species belonging to genus Sanguisorba. Numerous reports on the chemical constituents, pharmacologic effects, and toxicity of genus Sanguisorba are available in the literature. This review provides a comprehensive understanding of the current traditional applications of plants, which are supported by a large number of scientific experiments. Owing to these promising properties, this species is used in the treatment of various diseases, including influenza virus infection, inflammation, Alzheimer's disease, type 2 diabetes and leukopenia caused by bone marrow suppression. Moreover, the rich contents and biological effects of S. officinalis and S. minor facilitate these applications in dietary supplements and cosmetics. Therefore, the purpose of this review is to summarize the recent advances in the traditional uses, chemical constituents, pharmacological effects and clinical applications of genus Sanguisorba. The present comprehensive review may provide new insights for the future research on genus Sanguisorba.

Duck Hepatitis A Virus Type 1 Induces eIF2α Phosphorylation-Dependent Cellular Translation Shutoff via PERK/GCN2.

Duck hepatitis A virus type 1 (DHAV-1) is one of the most deadly pathogens that endanger the duck industry. Most viruses usually turn off host translation after infection to facilitate viral replication and translation. For the first time report to our knowledge, DHAV-1 can induce eIF2α phosphorylation and inhibit cellular translation in duck embryo fibroblasts (DEFs). Moreover, the activity of DHAV-1 in the cells caused obvious eIF2α phosphorylation, which has nothing to do with the viral protein. Subsequently, we screened two kinases (PERK and GCN2) that affect eIF2α phosphorylation through inhibitors and shRNA. Notably, the role of GCN2 in other picornaviruses has not been reported. In addition, when the phosphorylation of eIF2α induced by DHAV-1 is inhibited, the translation efficiency of DEFs restores to a normal level, indicating that DHAV-1 induced cellular translation shutoff is dependent on eIF2α phosphorylation.

Simultaneous two-photon activation and imaging of neural activity based on spectral-temporal modulation of supercontinuum light.

SIGNIFICANCE: Recent advances in nonlinear optics in neuroscience have focused on using two ultrafast lasers for activity imaging and optogenetic stimulation. Broadband femtosecond light sources can obviate the need for multiple lasers by spectral separation for chromatically targeted excitation. AIM: We present a photonic crystal fiber (PCF)-based supercontinuum source for spectrally resolved two-photon (2P) imaging and excitation of GCaMP6s and C1V1-mCherry, respectively. APPROACH: A PCF is pumped using a 20-MHz repetition rate femtosecond laser to generate a supercontinuum of light, which is spectrally separated, compressed, and recombined to image GCaMP6s (930 nm excitation) and stimulate the optogenetic protein, C1V1-mCherry (1060 nm excitation). Galvanometric spiral scanning is employed on a single-cell level for multiphoton excitation and high-speed resonant scanning is employed for imaging of calcium activity. RESULTS: Continuous wave lasers were used to verify functionality of optogenetic activation followed by directed 2P excitation. Results from these experiments demonstrate the utility of a supercontinuum light source for simultaneous, single-cell excitation and calcium imaging. CONCLUSIONS: A PCF-based supercontinuum light source was employed for simultaneous imaging and excitation of calcium dynamics in brain tissue. Pumped PCFs can serve as powerful light sources for imaging and activation of neural activity, and overcome the limited spectra and space associated with multilaser approaches.

Structures and Functions of the 3' Untranslated Regions of Positive-Sense Single-Stranded RNA Viruses Infecting Humans and Animals.

The 3' untranslated region (3' UTR) of positive-sense single-stranded RNA [ssRNA(+)] viruses is highly structured. Multiple elements in the region interact with other nucleotides and proteins of viral and cellular origin to regulate various aspects of the virus life cycle such as replication, translation, and the host-cell response. This review attempts to summarize the primary and higher order structures identified in the 3'UTR of ssRNA(+) viruses and their functional roles.

Single-shot two-dimensional spectroscopic magnetomotive optical coherence elastography with graphics processing unit acceleration.

Biomechanical contrast within tissues can be assessed based on the resonant frequency probed by spectroscopic magnetomotive optical coherence elastography (MM-OCE). However, to date, in vivo MM-OCE imaging has not been achieved, mainly due to the constraints on imaging speed. Previously, spatially-resolved spectroscopic contrast was achieved in a "multiple-excitation, multiple-acquisition" manner, where seconds of coil cooling time set between consecutive imaging frames lead to total acquisition times of tens of minutes. Here, we demonstrate an improved data acquisition speed by providing a single chirped force excitation prior to magnetomotion imaging with a BM-scan configuration. In addition, elastogram reconstruction was accelerated by exploiting the parallel computing capability of a graphics processing unit (GPU). The accelerated MM-OCE platform achieved data acquisition in 2.9 s and post-processing in 0.6 s for a 2048-frame BM-mode stack. In addition, the elasticity sensing functionality was validated on tissue-mimicking phantoms with high spatial resolution. For the first time, to the best of our knowledge, MM-OCE images were acquired from the skin of a living mouse, demonstrating its feasibility for in vivo imaging.

The role of host eIF2α in viral infection.

BACKGROUND: eIF2α is a regulatory node that controls protein synthesis initiation by its phosphorylation or dephosphorylation. General control nonderepressible-2 (GCN2), protein kinase R-like endoplasmic reticulum kinase (PERK), double-stranded RNA (dsRNA)-dependent protein kinase (PKR) and heme-regulated inhibitor (HRI) are four kinases that regulate eIF2α phosphorylation. MAIN BODY: In the viral infection process, dsRNA or viral proteins produced by viral proliferation activate different eIF2α kinases, resulting in eIF2α phosphorylation, which hinders ternary tRNAMet-GTP-eIF2 complex formation and inhibits host or viral protein synthesis. The stalled messenger ribonucleoprotein (mRNP) complex aggregates under viral infection stress to form stress granules (SGs), which encapsulate viral RNA and transcription- and translation-related proteins, thereby limiting virus proliferation. However, many viruses have evolved a corresponding escape mechanism to synthesize their own proteins in the event of host protein synthesis shutdown and SG formation caused by eIF2α phosphorylation, and viruses can block the cell replication cycle through the PERK-eIF2α pathway, providing a favorable environment for their own replication. Subsequently, viruses can induce host cell autophagy or apoptosis through the eIF2α-ATF4-CHOP pathway. CONCLUSIONS: This review summarizes the role of eIF2α in viral infection to provide a reference for studying the interactions between viruses and hosts.