The value of radiographic features in predicting postoperative facial nerve function in vestibular schwannoma patients: A retrospective study and nomogram analysis.

OBJECTIVE: The purpose of this study was to identify significant prognostic factors associated with facial paralysis after vestibular schwannoma (VS) surgery and develop a novel nomogram for predicting facial nerve (FN) outcomes. METHODS: Retrospective data were retrieved from 355 patients who underwent microsurgery via the retrosigmoid approach for VS between December 2017 and December 2022. Univariate and multivariate logistic regression analysis were used to construct a radiographic features-based nomogram to predict the risk of facial paralysis after surgery. RESULTS: Following a thorough screening process, a total of 185 participants were included. The univariate and multivariate logistic regression analysis revealed that tumor size (p = 0.005), fundal fluid cap (FFC) sign (p = 0.014), cerebrospinal fluid cleft (CSFC) sign (p < 0.001), and expansion of affected side of internal auditory canal (IAC) (p = 0.033) were independent factors. A nomogram model was constructed based on these indicators. When applied to the validation cohort, the nomogram demonstrated good discrimination and favorable calibration. Then we generated a web-based calculator to facilitate clinical application. CONCLUSION: Tumor size, FFC and CSFC sign, and the expansion of the IAC, serve as good predictors of postoperative FN outcomes. Based on these factors, the nomogram model demonstrates good predictive performance.

ATP-Coated Dual-Functionalized Titanium(IV) IMAC Material for Simultaneous Enrichment and Separation of Glycopeptides and Phosphopeptides.

Protein glycosylation and phosphorylation are two of the most common post-translational modifications (PTMs), which play an important role in many biological processes. However, low abundance and poor ionization efficiency of phosphopeptides and glycopeptides make direct MS analysis challenging. In this study, we developed a hydrophilicity-enhanced bifunctional Ti-IMAC (IMAC: immobilized metal affinity chromatography) material with grafted adenosine triphosphate (denoted as epoxy-ATP-Ti4+) to enable simultaneous enrichment and separation of common N-glycopeptides, phosphopeptides, and M6P glycopeptides from tissue/cells. The enrichment was achieved through a dual-mode mechanism based on the electrostatic and hydrophilic properties of the material. The epoxy-ATP-Ti4+ IMAC material was prepared from epoxy-functionalized silica particles via a convenient two-step process. The ATP molecule provided strong and active phosphate sites for binding phosphopeptides in the conventional IMAC mode and also contributed significantly to the hydrophilicity, which permitted the enrichment of glycopeptides via hydrophilic interaction chromatography. The two modes could be implemented simultaneously, allowing glycopeptides and phosphopeptides to be collected sequentially in a single experiment from the same sample. In addition to standard protein samples, the material was further applied to glycopeptide and phosphopeptide enrichment and characterization from HeLa cell digests and mouse lung tissue samples. In total, 2928 glycopeptides and 3051 phosphopeptides were identified from the mouse lung tissue sample, supporting the utility of this material for large-scale PTM analysis of complex biological samples. Overall, the newly developed epoxy-ATP-Ti4+ IMAC material and associated fractionation method enable simple and effective enrichment and separation of glycopeptides and phosphopeptides, offering a useful tool to study potential crosstalk between these two important PTMs in biological systems. The MS data have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with the data set identifier PXD029775.

Gadolinium (III)-Chelated Deformable Mesoporous Organosilica Nanoparticles as Magnetic Resonance Imaging Contrast Agent.

Magnetic resonance imaging (MRI) contrast agents, such as Magnevist (Gd-DTPA), are routinely used for detecting tumors at an early stage. However, the rapid clearance by the kidney of Gd-DTPA leads to short blood circulation time, which limits further improvement of the contrast between tumorous and normal tissue. Inspired by the deformability of red blood cells, which improves their blood circulation, this work fabricates a novel MRI contrast agent by incorporating Gd-DTPA into deformable mesoporous organosilica nanoparticles (D-MON). In vivo distribution shows that the novel contrast agent is able to depress rapid clearance by the liver and spleen, and the mean residence time is 20 h longer than Gd-DTPA. Tumor MRI studies demonstrated that the D-MON-based contrast agent is highly enriched in the tumor tissue and achieves prolonged high-contrast imaging. D-MON significantly improves the performance of clinical contrast agent Gd-DTPA, exhibiting good potential in clinical applications.

Signal Amplification Pretargeted PET/Fluorescence Imaging Based on Human Serum Albumin-Encapsulated GdF3 Nanoparticles for Diagnosis of Ovarian Cancer.

Different modal imaging techniques could be complementary in tumor diagnosis. Human serum albumin (HSA)-encapsulated GdF3 nanoparticles were developed as T1 magnetic resonance imaging (MRI) contrast agents. However, no significant T1 enhancement in the tumor site of the SKOV3 human ovarian cancer xenograft tumor model was observed within 3 h after injection of tetrazine-modified GdF3@HSA NPs through small-animal MRI. After intravenous injection of 18F (or Cy7)-labeled Reppe anhydride, pretargeted positron emission tomography (PET) (near-infrared (NIR) fluorescence) imaging was used to reveal the pharmacokinetics of GdF3@HSA NPs in the SKOV3 xenograft mouse model to locate the tumor. The probe based on Reppe anhydride achieved rapid ligation with tetrazine-modified GdF3@HSA nanoparticles (NPs), which accumulated in tumor through Reppe anhydride/tetrazine bioorthogonal chemistry. This pretargeting strategy enabled excellent tumor visualization and quantification at an early period after nanoparticle injection (3 h p.i.), while the MRI images with significant T1 enhancement could be obtained until 24 h after injection of Gd-based contrast agents only. In vivo pretargeted multimodal imaging based on the tetrazine/Reppe anhydride system using HSA-encapsulated GdF3 nanoparticles would be beneficial for amplification of the imaging signal in the disease site and enhancing diagnostic efficiency.

A Nomogram to Predict Recurrence-Free Survival Following Surgery for Vestibular Schwannoma.

Background: Vestibular schwannoma (VS) is the most common benign tumor of the posterior fossa. The recurrence of VS has always received widespread attention. This study aimed to develop a nomogram to predict Recurrence-free survival (RFS) following resection of VS. Methods: A total of 425 patients with VS who underwent resection at the Department of Neurosurgery in Chinese PLA General Hospital between January 2014 and December 2020 were enrolled in this retrospective study. The medical records and follow-up data were collected. Cox regression analysis was used to screen prognostic factors and construct the nomogram. The predictive accuracy and clinical benefits of the nomogram were validated using the area under the curve (AUC), calibration curves, and decision curve analysis (DCA). Results: The Cox regression analysis revealed that age (HR = 0.96; 95% CI 0.94 - 0.99; p < 0.01), EOR (HR = 4.65; 95% CI 2.22 - 9.74; p < 0.001), and Ki-67 (HR = 1.16; 95% CI 1.09 - 1.23; p < 0.001) were all significantly correlated with recurrence, and they were finally included in the nomogram model. The concordance index of the nomogram was 0.86. The areas under the curve (AUCs) of the nomogram model of 3-, 4- and 5-year were 0.912, 0.865, and 0.809, respectively. A well-fitted calibration curve was also generated for the nomogram model. The DCA curves also indicated that the nomogram model had satisfactory clinical utility compared to the single indicators. Conclusions: We developed a nomogram that has high accuracy in predicting RFS in patients after resection of VS. All of the included prognostic factors are easy to obtain. The nomogram can improve the postoperative management of patients and assist clinicians in individualized clinical treatment. Furthermore, we generated a web-based calculator to facilitate clinical application: https://abc123-123.shinyapps.io/VS-RFS/.

Selective Enrichment of Sialylglycopeptides Enabled by Click Chemistry and Dynamic Covalent Exchange.

Despite the important roles of protein sialylation in biological processes such as cellular interaction and cancer progression, simple and effective methods for the analysis of intact sialylglycopeptides (SGPs) are still limited. Analyses of low-abundance SGPs typically require efficient enrichment prior to comprehensive liquid chromatography-mass spectrometry (LC-MS)-based analysis. Here, a novel workflow combining mild periodate oxidation, hydrazide chemistry, copper-catalyzed azide/alkyne cycloaddition (CuAAC) click chemistry, and dynamic covalent exchange has been developed for selective enrichment of SGPs. The intact SGPs could be separated easily from protein tryptic digests, and the signature ions were produced during LC-MS/MS for unambiguous identification. The structure of the signature ions and corresponding dynamic covalent exchange were confirmed by using an isotopic reagent. Under the optimized condition, over 70% enrichment efficiency of SGPs was achieved using bovine fetuin digests, and the method was successfully applied to complex biological samples, such as a mouse lung tissue extract. The high enrichment efficiency, good reproducibility, and easily adopted procedure without the need to generate specialized materials make this method a promising tool for broad applications in SGP analysis.

Multimodality imaging in the assessment of bone marrow-derived mesenchymal stem cell therapy for doxorubicin-induced cardiomyopathy.

Due to their broad-spectrum effects and high antitumor efficacies, anthracycline-based chemotherapies are commonly prescribed in various solid and hematological malignancies. Doxorubicin (DOX) is one of the most highly used anthracyclines but has been shown to cause lethal cardiomyopathy in clinical practice. Studies have demonstrated that bone marrow-derived mesenchymal stem cells (BMSCs) have the ability to rescue DOX-induced cardiomyopathy (DIC). However, novel molecular imaging techniques are required to explore the biological behaviors, safety, eventual viability, and environmental interactions of transplanted stem cells during therapy. To investigate the biological behaviors of transplanted BMSCs, we applied bioluminescence imaging (BLI) and magnetic resonance imaging (MRI) techniques to trace firefly luciferase (Fluc) and ultrasmall superparamagnetic iron oxide (USPIO) double-labeled mouse BMSCs after injection into the heart apex in a chronic DIC mouse model. Then, we determined the optimal BMSC number for transplantation into the heart and optimized MRI parameters to evaluate transplanted BMSCs in vitro and in vivo. Our results showed that the BLI trace signal could last 7 days in the DIC mouse model, whereas the MRI signal lasted up to 3 days. However, MRI provided more detailed pathophysiological information on DIC than BLI, such as inflammation and fibrosis signs. The optimal in vivo cell number for BLI and MRI was determined to be 1×106. In conclusion, BLI combined with multimodality MRI could be used to monitor the biological behavior of BMSCs transplanted into a chronic DIC mouse model in a visual and dynamic manner.

Real-time in vivo imaging reveals specific nanoparticle target binding in a syngeneic glioma mouse model.

Nanomaterial-based drug delivery is a promising strategy for glioma treatment. However, the detailed dynamics of nanoparticles in solid glioma are still a mystery, including their intratumoral infiltration depth, penetration, retention time, and distribution. Revealing these processes in detail requires repeated intravital imaging of the corresponding brain tumor regions over time during glioma growth. Hereby, we established a syngeneic orthotopic cerebral glioma mouse model by combining the chronic cranial window and two-photon microscopy. Thus, we were able to investigate the dynamics of the nanoparticles during long-term glioma growth. Three hours after the intravenous (i.v.) injection of integrin αVß3 binding conjugated silicon nanoparticles (SNPs-PEG-RGD-FITC), green nanoparticles had already infiltrated the brain glioma, and then more nanoparticles penetrated into the solid brain tumor and were retained for at least 8 days. However, the amount of control SNPs-PEG-FITC that infiltrated into the solid brain tumor was very low. Moreover, we found that SNPs-PEG-RGD-FITC were not only located in the tumor border but could also infiltrate into the core region of the solid tumor. In vitro assay also confirmed the high binding affinity between GL-261-Tdtomato cells and SNPs-PEG-RGD-FITC. Our results indicate that SNPs-PEG-RGD-FITC has high penetration and retention in a solid glioma and our model provides novel ideas for the investigation of nanoparticle dynamics in brain tumors.

On-tissue amidation of sialic acid with aniline for sensitive imaging of sialylated N-glycans from FFPE tissue sections via MALDI mass spectrometry.

Spatial visualization of glycans within clinical tissue samples is critical for discovery of disease-relevant glycan dysregulations. Herein, we develop an on-tissue derivatization strategy for sensitive spatial visualization of N-glycans from formalin-fixed paraffin-embedded (FFPE) tissue sections, based on amidation of sialic acid residues with aniline. The sialylated N-glycans were stabilized and given enhanced signal intensity owing to selective capping of a phenyl group to the sialic acid residue after aniline labeling. Proof-of-concept experiments, including determinations of sialylglycopeptide and N-glycans enzymatically released from glycoproteins, were performed. Further, mass spectrometry (MS) imaging of N-glycans on human laryngeal cancer FFPE tissue sections was conducted via matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI), based on our strategy for on-tissue amidation of sialylated N-glycans. We obtained higher sialylated N-glycan coverages for both the glycoproteins and cancer tissue samples, demonstrating that the detection sensitivity for sialylated N-glycans is notably improved by amidation derivatization. We also characterized N-glycan heterogeneity across the human laryngeal cancer tissue section, showing N-glycan dysregulation in the tumor region.

Immobilization of Glycogen Synthase Kinase-3ß Inhibitor on 316L Stainless Steel via Polydopamine to Accelerate Endothelialization.

The coverage of stents with healthy endothelium is crucial to the success of cardiovascular stent implantation. Immobilizing bioactive molecules on stents is an effective strategy to generate such stents. Glycogen synthase kinase-3ß inhibitor (GSKi) is a bioactive molecule that can effectively accelerate vascular endothelialization. In this work, GSKi was covalently conjugated on 316L stainless steel through polydopamine to develop a stable bioactive surface. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and water contact angle results revealed the successful introduction of GSKi onto 316L stainless steel. The GSKi coating did not obviously affect the hemocompatibility of plates. The adhesion and proliferation of human coronary artery endothelial cells (HCAECs) on stainless steel was significantly promoted by the addition of GSKi. In summary, this work provides a universal and stable strategy of immobilizing GSKi on the stent surface. This method has the potential for widespread application in the modification of vascular stents.

Comparative transcriptomic analysis of THP-1-derived macrophages infected with Mycobacterium tuberculosis H37Rv, H37Ra and BCG.

Tuberculosis (TB) remains a worldwide healthcare concern, and the exploration of the host-pathogen interaction is essential to develop therapeutic modalities and strategies to control Mycobacterium tuberculosis (M.tb). In this study, RNA sequencing (transcriptome sequencing) was employed to investigate the global transcriptome changes in the macrophages during the different strains of M.tb infection. THP-1 cells derived from macrophages were exposed to the virulent M.tb strain H37Rv (Rv) or the avirulent M.tb strain H37Ra (Ra), and the M.tb BCG vaccine strain was used as a control. The cDNA libraries were prepared from M.tb-infected macrophages and then sequenced. To assess the transcriptional differences between the expressed genes, the bioinformatics analysis was performed using a standard pipeline of quality control, reference mapping, differential expression analysis, protein-protein interaction (PPI) networks, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Q-PCR and Western blot assays were also performed to validate the data. Our findings indicated that, when compared to BCG or M.tb H37Ra infection, the transcriptome analysis identified 66 differentially expressed genes in the M.tb H37Rv-infected macrophages, out of which 36 genes were up-regulated, and 30 genes were down-regulated. The up-regulated genes were associated with immune response regulation, chemokine secretion, and leucocyte chemotaxis. In contrast, the down-regulated genes were associated with amino acid biosynthetic and energy metabolism, connective tissue development and extracellular matrix organization. The Q-PCR and Western blot assays confirmed increased expression of pro-inflammatory factors, altered energy metabolic processes, enhanced activation of pro-inflammatory signalling pathways and increased pyroptosis in H37Rv-infected macrophage. Overall, our RNA sequencing-based transcriptome study successfully identified a comprehensive, in-depth gene expression/regulation profile in M.tb-infected macrophages. The results demonstrated that virulent M.tb strain H37Rv infection triggers a more severe inflammatory immune response associated with increased tissue damage, which helps in understanding the host-pathogen interaction dynamics and pathogenesis features in different strains of M.tb infection.

Quantification and molecular imaging of fatty acid isomers from complex biological samples by mass spectrometry.

Elucidating the isomeric structure of free fatty acids (FAs) in biological samples is essential to comprehend their biological functions in various physiological and pathological processes. Herein, we report a novel approach of using peracetic acid (PAA) induced epoxidation coupled with mass spectrometry (MS) for localization of the C[double bond, length as m-dash]C bond in unsaturated FAs, which enables both quantification and spatial visualization of FA isomers from biological samples. Abundant diagnostic fragment ions indicative of the C[double bond, length as m-dash]C positions were produced upon fragmentation of the FA epoxides derived from either in-solution or on-tissue PAA epoxidation of free FAs. The performance of the proposed approach was evaluated by analysis of FAs in human cell lines as well as mapping the FA isomers from cancer tissue samples with MALDI-TOF/TOF-MS. Merits of the newly developed method include high sensitivity, simplicity, high reaction efficiency, and capability of spatial characterization of FA isomers in tissue samples.

High-resolution magnetic resonance and mass spectrometry imaging of the human larynx.

High-resolution, noninvasive and nondestructive imaging of the subepithelial structures of the larynx would enhance microanatomic tissue assessment and clinical decision making; similarly, in situ molecular profiling of laryngeal tissue would enhance biomarker discovery and pathology readout. Towards these goals, we assessed the capabilities of high-resolution magnetic resonance imaging (MRI) and matrix-assisted laser desorption/ionisation-mass spectrometry (MALDI-MS) imaging of rarely reported paediatric and adult cadaveric larynges that contained pathologies. The donors were a 13-month-old male, a 10-year-old female with an infraglottic mucus retention cyst and a 74-year-old female with advanced polypoid degeneration and a mucus retention cyst. MR and molecular imaging data were corroborated using whole-organ histology. Our MR protocols imaged the larynges at 45-117 µm2 in-plane resolution and capably resolved microanatomic structures that have not been previously reported radiographically-such as the vocal fold superficial lamina propria, vocal ligament and macula flavae; age-related tissue features-such as intramuscular fat deposition and cartilage ossification; and the lesions. Diffusion tensor imaging characterised differences in water diffusivity, primary tissue fibre orientation, and fractional anisotropy between the intrinsic laryngeal muscles, mucosae and lesions. MALDI-MS imaging revealed peptide signatures and putative protein assignments for the polypoid degeneration lesion and the N-glycan constituents of one mucus retention cyst. These imaging approaches have immediate application in experimental research and, with ongoing technology development, potential for future clinical application.

SARS-CoV-2 infection aggravates chronic comorbidities of cardiovascular diseases and diabetes in mice.

Background: Cardiovascular diseases (CVDs) and diabetes mellitus (DM) are top two chronic comorbidities that increase the severity and mortality of COVID-19. However, how SARS-CoV-2 alters the progression of chronic diseases remain unclear. Methods: We used adenovirus to deliver h-ACE2 to lung to enable SARS-CoV-2 infection in mice. SARS-CoV-2's impacts on pathogenesis of chronic diseases were studied through histopathological, virologic and molecular biology analysis. Results: Pre-existing CVDs resulted in viral invasion, ROS elevation and activation of apoptosis pathways contribute myocardial injury during SARS-CoV-2 infection. Viral infection increased fasting blood glucose and reduced insulin response in DM model. Bone mineral density decreased shortly after infection, which associated with impaired PI3K/AKT/mTOR signaling. Conclusion: We established mouse models mimicked the complex pathological symptoms of COVID-19 patients with chronic diseases. Pre-existing diseases could impair the inflammatory responses to SARS-CoV-2 infection, which further aggravated the pre-existing diseases. This work provided valuable information to better understand the interplay between the primary diseases and SARS-CoV-2 infection.

Proteomic and Genomic Methylation Signatures of Idiopathic Subglottic Stenosis.

OBJECTIVE: Idiopathic subglottic stenosis (iSGS) is a chronic inflammatory condition that causes dyspnea and affects middle-aged women of White race and non-Latino or Hispanic ethnicity. To better characterize its phenotype and pathogenesis, we assessed the proteomic and genomic methylation signatures of subglottic tissue collected from iSGS patients compared to controls. STUDY DESIGN: Molecular analysis of clinical biospecimens. METHODS: We collected subglottic tissue biopsies from 12 patients during direct laryngoscopy, immediately prior to surgical treatment of iSGS; as well as from 4 age-, sex-, and race/ethnicity-matched control patients undergoing other direct laryngoscopic procedures. We isolated protein and genomic DNA, acquired proteomic data using label-free quantitative mass spectrometry techniques, and acquired genome-wide methylation data using bisulfite conversion and a microarray platform. We compared molecular profiles across the iSGS and control groups, and with respect to clinical course in the iSGS group. Eight of the 12 iSGS patients underwent subsequent blood collection and plasma isolation for further assessment. RESULTS: Proteomic analysis revealed 42 differentially abundant proteins in the iSGS biopsies compared to controls, inferring enrichment of biological pathways associated with early wound healing, innate immunity, matrix remodeling, and metabolism. Proteome-based hierarchical clustering organized patients into two iSGS and one control subgroups. Methylation analysis revealed five hypermethylated genes in the iSGS biopsies compared to controls, including the biotin recycling enzyme biotinidase (BTD). Follow-up analysis showed elevated plasma BTD activity in iSGS patients compared to both controls and published normative data. CONCLUSION: iSGS exhibits distinct proteomic and genomic methylation signatures. These signatures expand current understanding of the iSGS phenotype, support the possibility of disease subgroups, and should inform the direction of future experimental studies. LEVEL OF EVIDENCE: Not applicable Laryngoscope, 131:E540-E546, 2021.

Multifunctional Transferrin Encapsulated GdF3 Nanoparticles for Sentinel Lymph Node and Tumor Imaging.

The transferrin encapsulated GdF3 nanoparticles have been fabricated via biomineralization method. The obtained GdF3@Tf NPs show an attractive T2MRI and CT enhancement effect. Furthermore, PET and NIR imaging capacity are integrated into nanoparticles through conjugating with radionuclide 64Cu and fluorescent dye Cy7. 64Cu-GdF3@Tf-Cy7 NPs are developed and applied in small animal multimodal imaging in vivo. Compared with the previous multimodal imaging agents, 64Cu-GdF3@Tf-Cy7 NPs enable not only precise sentinel lymph node (SLN) identification, but specific imaging for transferrin receptor overexpressed colorectal tumor in vivo. The results reveal that 64Cu-GdF3@Tf-Cy7 NPs are potential and efficient multimodal imaging agents for SLN and tumor preclinical imaging.

On-Tissue Derivatization with Girard's Reagent P Enhances N-Glycan Signals for Formalin-Fixed Paraffin-Embedded Tissue Sections in MALDI Mass Spectrometry Imaging.

Glycosylation is a major protein post-translational modification whose dysregulation has been associated with many diseases. Herein, an on-tissue chemical derivatization strategy based on positively charged hydrazine reagent (Girard's reagent P) coupled with matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) was developed for analysis of N-glycans from FFPE treated tissue sections. The performance of the proposed approach was evaluated by analysis of monosaccharides, oligosaccharides, N-glycans released from glycoproteins, as well as MS imaging of N-glycans from human cancer tissue sections. The results demonstrated that the signal-to-noise ratios for target saccharides were notably improved after chemical derivatization, in which signals were enhanced by 230-fold for glucose and over 28-fold for maltooctaose. Improved glycome coverage was obtained for N-glycans derived from glycoproteins and tissue samples after chemical derivatization. Furthermore, on-tissue derivatization was applied for MALDI-MSI of N-glycans from human laryngeal cancer and ovarian cancer tissues. Differentially expressed N-glycans among the tumor region, adjacent normal tissue region, and tumor proximal collagen stroma region were imaged, revealing that high-mannose type N-glycans were predominantly expressed in the tumor region. Overall, our results indicate that the on-tissue labeling strategy coupled with MALDI-MSI shows great potential to spatially characterize N-glycan expression within heterogeneous tissue samples with enhanced sensitivity. This study provides a promising approach to better understand the pathogenesis of cancer related aberrant glycosylation, which is beneficial to the design of improved clinical diagnosis and therapeutic strategies.

Mass Spectrometry Imaging of N-Glycans from Formalin-Fixed Paraffin-Embedded Tissue Sections Using a Novel Subatmospheric Pressure Ionization Source.

N-linked glycosylation, featuring various glycoforms, is one of the most common and complex protein post-translational modifications (PTMs) controlling protein structures and biological functions. It has been revealed that abnormal changes of protein N-glycosylation patterns are associated with many diseases. Hence, unraveling the disease-related alteration of glycosylation, especially the glycoforms, is crucial and beneficial to improving our understanding about the pathogenic mechanisms of various diseases. In past decades, given the capability of in situ mapping of biomolecules and their region-specific localizations, matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) has been widely applied to the discovery of potential biomarkers for many diseases. In this study, we coupled a novel subatmospheric pressure (SubAP)/MALDI source with a Q Exactive HF hybrid quadrupole-orbitrap mass spectrometer for in situ imaging of N-linked glycans from formalin-fixed paraffin-embedded (FFPE) tissue sections. The utility of this new platform for N-glycan imaging analysis was demonstrated with a variety of FFPE tissue sections. A total of 55 N-glycans were successfully characterized and visualized from a FFPE mouse brain section. Furthermore, 29 N-glycans with different spatial distribution patterns could be identified from a FFPE mouse ovarian cancer tissue section. High-mannose N-glycans exhibited elevated expression levels in the tumor region, indicating the potential association of this type of N-glycans with tumor progression.

Characterization of non-tuberculous mycobacterial pulmonary disease in Nanjing district of China.

BACKGROUND: Environmental bacteria, nontuberculous mycobacteria (NTM), are recognized as one of the major human infection pathogens. NTM are prone to be mistaken as multidrug-resistant Mycobacterium tuberculosis and challenge our fight against TB. In addition, treatment of NTM per se is intractable. Remarkably, the distribution of NTM pathogenic species is geographically specific. Thus, it is very important to summarize the prevalent features and clinical symptoms of NTM pulmonary disease. However, In Nanjing district, southeast China, there is no such a report. METHODS: Through investigating electronic medical records and analyzing data of clinical examination system (Lis), we retrospectively summarized the NTM species from 6012 clinical isolates from May 2017 to August 2018, and analyzed the association between NTM species and clinical symptoms. RESULTS: Of 6012 clinical specimens, 1461 (24.3%) could grow in the MGIT 960 broth. Among these positive isolates, 1213 (83%) were M. tuberculosis, 22 (1.5%) were M. bovis, and 226 (15.5%) were NTM. After deducting redundancy, those NTM specimens were confirmed from 154 patients, among which, 87 (56.5%) patients met the full ATS/IDSA NTM disease criteria. The most common etiologic agent was M. intracellulare (70.1%). NTM infection was associated with age, based on which 68.6% male patients and 77.8% female patients were over 50 years old. The older patients were more likely to have hemoptysis, but the younger patients were more likely to manifest chest congestion. Male patients were more likely to have shortness of breath and females were more likely to have hemoptysis. The most common radiographic presentation of NTM pulmonary disease was bronchiectasis, accounting for 39.1%. Remarkably, multiple and thin-walled cavities were outstanding. The most frequent comorbidity of NTM disease was previous tuberculosis (64%), followed by clinical bronchiectasis (19.5%), HIV (19.5%), and 6.9% chronic obstructive pulmonary disease (COPD). There was no association between NTM species and clinical symptoms. CONCLUSION: This study retrospectively investigated the prevalence of NTM pulmonary disease in Nanjing district, southeast China. Similar to Beijing area, north China, M. intracellulare was the major pathogenic NTM species. Clinical symptoms of the disease were not species-specific. Previous TB and HIV infection immensely enhanced risk of NTM disease.

Dual-Functional Titanium(IV) Immobilized Metal Affinity Chromatography Approach for Enabling Large-Scale Profiling of Protein Mannose-6-Phosphate Glycosylation and Revealing Its Predominant Substrates.

Mannose-6-phosphate (M6P) glycosylation is an important post-translational modification (PTM) and plays a crucial role in transferring lysosomal hydrolases to lysosome, and is involved in several other biological processes. Aberrant M6P modifications have been implicated in lysosomal storage diseases and numerous other disorders including Alzheimer's disease and cancer. Research on profiling of intact M6P glycopeptides remains challenging due to its extremely low stoichiometry. Here we propose a dual-mode affinity approach to enrich M6P glycopeptides by dual-functional titanium(IV) immobilized metal affinity chromatography [Ti(IV)-IMAC] materials. In combination with state-of-the-art mass spectrometry and database search engine, we profiled 237 intact M6P glycopeptides corresponding to 81 M6P glycoproteins in five types of tissues in mouse, representing the first large-scale profiling of M6P glycosylation in mouse samples. The analysis of M6P glycoforms revealed the predominant glycan substrates of this PTM. Gene ontology analysis showed that overrepresented M6P glycoproteins were lysosomal-associated proteins. However, there were still substantial M6P glycoproteins that possessed different subcellular locations and molecular functions. Deep mining of their roles implicated in lysosomal and nonlysosomal function can provide new insights into functional roles of this important yet poorly studied modification.