Detection of early pulmonary emphysema by multi-contrast x-ray Talbot-Lau interferometer.

BACKGROUND: Pulmonary emphysema is a part of chronic obstructive pulmonary disease, which is an irreversible chronic respiratory disease. In order to avoid further damage to lung tissue, early diagnosis and treatment of pulmonary emphysema is essential. PURPOSE: Early pulmonary emphysema diagnosis is difficult with conventional radiographic imaging. Recently, x-ray phase contrast imaging has proved to be an effective and promising imaging strategy for soft tissue, due to its high sensitivity and multi-contrast. The aim of this study is to diagnose pulmonary emphysema early utilizing an x-ray Talbot-Lau interferometer (TLI). METHODS: We successfully established the mouse model of emphysema by porcine pancreatic elastase treatment, and then used the established x-ray TLI to perform imaging experiments on the mice with different treatment time. The traditional absorption CT and phase contrast CT were obtained simultaneously through TLI. The CT results and histopathology of mice lung in different treatment time were quantitatively analyzed. RESULTS: By imaging mice lungs, it can be found that phase contrast has higher sensitivity than absorption contrast in early pulmonary emphysema. The results show that the phase contrast signal could distinguish the pulmonary emphysema earlier than the conventional attenuation signal, which can be consistent with histological images. Through the quantitative analysis of pathological section and phase contrast CT, it can be found that there is a strong linear correlation. CONCLUSIONS: In this study, we quantitatively analyze mean linear intercept of histological sections and CT values of mice. The results show that the phase contrast signal has higher imaging sensitivity than the attenuation signal. X-ray TLI multi-contrast imaging is proved as a potential diagnostic method for early pulmonary emphysema in mice.

Photochemical Mn-Mediated Generation of Azide Radicals for Improvement of Alkene Hydroxyazidation.

State-of-the-art strategies for alkene-hydroxyazidation, which yield a mixture of ß-azido alcohol and ß-azido peroxide, must rely on phosphine reagents to improve the chemoselectivity. To overcome the above problems, we present a photochemical hydroxyazidation of alkenes via Mn-mediated ligand-to-metal charge transfer (LMCT) in O2, which activates N3- to •N3 and incorporates O2 to be used as an oxygen source in the hydroxyazidation products. Broad alkene range and step-economy chemistry for the hydroxyazidation transformation were also demonstrated.

The underlying neuropsychological and neural correlates of the impaired Chinese reading skills in children with attention deficit hyperactivity disorder.

Impaired basic academic skills (e.g., word recognition) are common in children with Attention Deficit Hyperactivity Disorder (ADHD). The underlying neuropsychological and neural correlates of impaired Chinese reading skills in children with ADHD have not been substantially explored. Three hundred and two children with ADHD (all medication-naïve) and 105 healthy controls underwent the Chinese language skill assessment, and 175 also underwent fMRI scans (84 ADHD and 91 controls). Between-group and mediation analyses were applied to explore the interrelationships of the diagnosis of ADHD, cognitive dysfunction, and impaired reading skills. Five ADHD-related brain functional networks, including the default mode network (DMN) and the dorsal attention network (DAN), were built using predefined regions of interest. Voxel-based group-wise comparisons were performed. The ADHD group performed worse than the control group in word-level reading ability tests, with lower scores in Chinese character recognition (CR) and word chains (WS) (all P < 0.05). With full-scale IQ and sustained attention in the mediation model, the direct effect of ADHD status on the CR score became insignificant (P = 0.066). The underlying neural correlates for the orthographic knowledge (OT) and CR differed between the ADHD and the control group. The ADHD group tended to recruit more DMN regions to maintain their reading performance, while the control group seemed to utilize more DAN regions. Children with ADHD generally presented impaired word-level reading skills, which might be caused by impaired sustained attention and lower IQ. According to the brain functional results, we infer that ADHD children might utilize a different strategy to maintain their orthographic knowledge and character recognition performance.

Design of 2.45 GHz High-Efficiency Rectifying Circuit for Wireless RF Energy Collection System.

A 2.45 GHz high-efficiency rectifying circuit for a wireless radiofrequency (RF) energy collection system is proposed. The RF energy collection system is composed of a transmitting antenna, a receiving antenna, a rectifying circuit and a load. The designed receiving antenna is a kind of dual-polarised cross-dipole antenna; its bandwidth is 2.3-2.5 GHz and gain is 7.97 dBi. The proposed rectifying circuit adopts the technology of an output matching network, which can suppress the high-harmonic components. When the input power at 2.45 GHz is 13 dBm and the load is 2 kΩ, the highest conversion efficiency of RF-DC is 74.8%, and the corresponding maximum DC output voltage is 4.92 V. The experiment results are in good agreement with the simulation results, which shows a good application prospect.

Development and validation of nomograms to evaluate the survival outcome of HCC patients undergoing selective postoperative adjuvant TACE.

PURPOSE: The objective of this study was to develop and validate a novel prognostic nomogram to evaluate the survival benefit of hepatocellular carcinoma (HCC) patients receiving postoperative adjuvant transarterial chemoembolization (PA-TACE). MATERIALS AND METHODS: Clinical data of HCC patients who underwent hepatectomy at four medical centers were retrospectively analyzed, including those who received PA-TACE and those who did not. These two categories of patients were randomly allocated to the development and validation cohorts in a 7:3 ratio. RESULTS: A total of 1505 HCC patients who underwent hepatectomy were included in this study, comprising 723 patients who did not receive PA-TACE and 782 patients who received PA-TACE. Among them, patients who received PA-TACE experienced more adverse events, although these events were mild and manageable (Grade 1-2, all p < 0.05). Nomograms were constructed and validated for patients with and without PA-TACE using independent predictors that influenced disease-free survival (DFS) and overall survival (OS). These two nomograms had C-indices greater than 0.800 in the development cohort and exhibited good calibration and discrimination ability compared to six conventional HCC staging systems. Patients in the intermediate-to-high-risk group in the nomogram who received PA-TACE had higher DFS and OS (all p < 0.05). In addition, tumor recurrence was significantly controlled in the intermediate-to-high-risk group of patients who received PA-TACE, while there was no significant difference in the low-risk group of patients who received PA-TACE. CONCLUSION: The nomograms were developed and validated based on large-scale clinical data and can serve as online decision-making tools to predict survival benefits from PA-TACE in different subgroups of patients.

Apoptotic body-inspired nanotherapeutics efficiently attenuate osteoarthritis by targeting BRD4-regulated synovial macrophage polarization.

Bromodomain-containing protein 4 (BRD4) is the most well-studied BET protein that is important for the innate immune response. We recently revealed that targeting BRD4 triggers apoptosis in tumor-associated macrophages, but its role in synovial macrophages and joint inflammation is largely unknown. Herein, we demonstrated that BRD4 was highly expressed in the iNOS-positive M1 macrophages in the human and mouse osteoarthritis (OA) synovium, and conditional knockout of BRD4 in the myeloid lineage using Lyz2-cre; BRD4flox/flox mice significantly abolished anterior cruciate ligament transection (ACLT)-induced M1 macrophage accumulation and synovial inflammation. Accordingly, we successfully constructed apoptotic body-inspired phosphatidylserine-containing nanoliposomes (PSLs) loaded with the BRD4 inhibitor JQ1 to regulate inflammatory macrophages. JQ1-loaded PSLs (JQ1@PSLs) exhibited a higher cellular uptake by macrophages than fibroblast-like synoviocytes (FLSs) in vitro and in vivo, as well as the reduction in proinflammatory M1 macrophage polarization. Intra-articular injections of JQ1@PSLs showed prolonged retention within the joint, and remarkably reduced synovial inflammation and joint pain via suppressing M1 polarization accompanied by reduced TRPA1 expression by targeted inhibition of BRD4 in the macrophages, thus attenuating cartilage degradation during OA development. The results show that BRD4-inhibiting JQ1@PSLs can targeted-modulate macrophage polarization, which opens a new avenue for efficient OA therapy via a "Trojan horse".

Correction: The {Cu2I2} cluster bearing metal organic frameworks: crystal structures and fluorescence detecting performances towards cysteine and explosive molecules.

Correction for 'The {Cu2I2} cluster bearing metal organic frameworks: crystal structures and fluorescence detecting performances towards cysteine and explosive molecules' by Jiang Jiang et al., Dalton Trans., 2024, 53, 706-714, https://doi.org/10.1039/d3dt03363e.

Conserved molecular chaperone PrsA stimulates protective immunity against group A Streptococcus.

Group A Streptococcus (GAS) is a significant human pathogen that poses a global health concern. However, the development of a GAS vaccine has been challenging due to the multitude of diverse M-types and the risk of triggering cross-reactive immune responses. Our previous research has identified a critical role of PrsA1 and PrsA2, surface post-translational molecular chaperone proteins, in maintaining GAS proteome homeostasis and virulence traits. In this study, we aimed to further explore the potential of PrsA1 and PrsA2 as vaccine candidates for preventing GAS infection. We found that PrsA1 and PrsA2 are highly conserved among GAS isolates, demonstrating minimal amino acid variation. Antibodies specifically targeting PrsA1/A2 showed no cross-reactivity with human heart proteins and effectively enhanced neutrophil opsonophagocytic killing of various GAS serotypes. Additionally, passive transfer of PrsA1/A2-specific antibodies conferred protective immunity in infected mice. Compared to alum, immunization with CFA-adjuvanted PrsA1/A2 induced higher levels of Th1-associated IgG isotypes and complement activation and provided approximately 70% protection against invasive GAS challenge. These findings highlight the potential of PrsA1 and PrsA2 as universal vaccine candidates for the development of an effective GAS vaccine.

KLF3 promotes colorectal cancer growth by activating WNT1.

OBJECTIVE: The function of Kruppel-like factor 3 (KLF3) remains largely unexplored in colorectal cancer (CRC). METHODS: KLF3 expression in CRC was assessed through qPCR, western blotting, immunohistochemical assays, and The Cancer Genome Atlas (TCGA) database. The tumor-promoting capacity of KLF3 was explored by performing in vitro functional experiments using CRC cells. A subcutaneous nude mouse tumor assay was employed to evaluate tumor growth. To further elucidate the interaction between KLF3 and other factors, luciferase reporter assay, agarose gel electrophoresis, and ChIP analysis were performed. RESULTS: KLF3 was downregulated in CRC tissue and cells. Silencing of KLF3 increased the potential of CRC cells for proliferation, migration, and invasion, while its activation decreased these processes. Downregulated KLF3 was associated with accelerated tumor growth in vivo. Mechanistically, KLF3 was discovered to target the promoter sequence of WNT1. Consequently, the diminished expression of KLF3 led to the buildup of WNT1 and the WNT/ß-catenin pathway activation, consequently stimulating the progression of CRC. CONCLUSIONS: This investigation suggests that the involvement of KLF3/WNT1 regulatory pathway contributes to the progression of CRC, thereby emphasizing its promise as an important focus for future therapies aimed at treating CRC.

Continuous age- and sex-specific reference ranges of liver enzymes in Chinese children and application in pediatric non-alcoholic fatty liver disease.

BACKGROUND: Alanine aminotransferase (ALT) is widely used to screen patients with hepatic diseases. However, the current reference ranges (< 50 U/L) were developed by laboratories and have not been validated in populations with a large number of healthy individuals. METHODS: This study collected venous blood and anthropometric data from a total of 13,287 healthy children aged 3 months to 18 years who underwent routine physical examinations in the Department of Pediatric Healthcare. We applied the least mean square algorithm to establish age- and sex-related reference percentiles of serum levels of transaminases. For validation, we recruited 4276 children and adolescents with obesity/overweight who underwent evaluation and metabolic tests in the hospital. Using receiver operating characteristic curves, we determined age- and sex-specific upper limit percentiles of liver enzymes for fatty liver diseases. RESULTS: This study revealed a significant correlation between serum transaminase levels and age and sex (P < 0.01). These transaminase levels exhibited age- and sex-specific patterns. Among individuals in the non-alcoholic fatty liver disease (NAFLD) cohort, elevated ALT levels displayed a positive association with clinical markers of disease severity, including homeostatic model assessment of insulin resistance, waist-hip ratio, and serum uric acid levels (P < 0.01). According to the receiver operating characteristic curves, ALT levels at the 92.58th percentile for boys and the 92.07th percentile for girls yielded the highest accuracy and specificity. CONCLUSIONS: This study provides age- and sex-specific reference ranges for ALT, aspartate aminotransferase, and γ-glutamyltransferase in Chinese children and adolescents, making it the largest population study to date. Furthermore, the study establishes a precise upper limit for ALT levels, facilitating their use in NAFLD screening. Video Abstract.

Exploring the factors affecting the occurrence of postoperative MVI and the prognosis of hepatocellular carcinoma patients treated with hepatectomy: A multicenter retrospective study.

OBJECTIVE: To investigate the influencing factors affecting the occurrence of microvascular invasion (MVI) and the prognosis of hepatocellular carcinoma (HCC) patients treated with hepatectomy, and to explore how MVI affects prognosis in subgroups with different prognostic factors. METHODS: Clinical data of a total of 1633 patients treated surgically for HCC in four treatment centers were included, including 754 patients with MVI. By using the Cox risk regression model and the Mann-Whitney U-test, the common independent influences on prognosis and MVI were made clear. The incidence of MVI in various subgroups was then examined, as well as the relationship between MVI in various subgroups and prognosis. RESULTS: The Cox risk regression model showed that MVI, Child-Pugh classification, alpha-fetoprotein (AFP), hepatocirrhosis, tumor diameter, lymphocyte-to-monocyte ratio (LMR), and, Barcelona clinic liver cancer (BCLC) grade were independent determinants of overall survival (OS), and MVI, AFP, hepatocirrhosis, tumor diameter, and LMR were influencing determinants for disease-free survival (DFS). The receiver operating characteristic (ROC) curve showed that MVI was most closely associated with patient prognosis compared to other prognostic factors. AFP, hepatocirrhosis, tumor diameter, and LMR were discovered to be common influences on the prognosis of patients with HCC and MVI when combined with the results of the intergroup comparison of MVI. After grouping, it was showed that patients with hepatocirrhosis, positive AFP (AFP ≥ 20 ng/mL), tumor diameter >50 mm, and LMR ≤3.4 had a significantly higher incidence of MVI than patients in other subgroups, and all four subgroups of MVI-positive patients had higher rates of early recurrence and mortality (p < 0.05). CONCLUSIONS: MVI was found to be substantially linked with four subgroups of HCC patients with hepatocirrhosis, positive AFP, tumor diameter >50 mm, and LMR ≤3.4, and the prognosis of MVI-positive patients in all four subgroups tended to be worse.

Survival effects of postoperative adjuvant TACE in early-HCC patients with microvascular invasion: A multicenter propensity score matching.

Background: The presence of microvascular invasion (MVI) significantly worsens the surgical outcome of hepatocellular carcinoma (HCC). The purpose of this research was to investigate the survival benefit of adjuvant transarterial chemoembolization (TACE) in patients with MVI after hepatectomy. Methods: A retrospective analysis was conducted on 1372 HCC patients who underwent curative liver resection in four medical institutions. In order to minimize confounding factors and selection bias between groups, Propensity Score Matching (PSM) (1:1) was performed to ensure balanced clinical characteristics. Results: A total of 1056 patients were enrolled after PSM, including 672 patients with MVI and 384 patients without MVI. Adjuvant TACE improves DFS (Median, 36 months vs 14 months, p < 0.001) and OS (Median, NA vs 32 months, p < 0.001) in patients harboring MVI, but not in those (all p > 0.05) lacking MVI. In different different CNLC stages, adjuvant TACE improved DFS (CNLC stage I, Median, 37 vs 15 months; CNLC stage II, Median, 25 vs 11 months, p < 0.001) and OS (CNLC stage I, Median, NA vs 32 months, p < 0.001; CNLC stage II, Median, NA vs 26 months, p = 0.002) in patients who carried MVI, but not in those (CNLC stage I-II, all p > 0.05) who lacked MVI. Conclusions: Adjuvant TACE may be a potentially effective treatment option for improving survival outcomes in early-HCC patients harboring MVI, but not in those lacking MVI.

Near-Native Imaging of Label-Free Silver Nanoparticles-Triggered 3D Subcellular Ultrastructural Reorganization in Microalgae.

Understanding the spatial orientation of nanoparticles and the corresponding subcellular architecture events favors uncovering fundamental toxic mechanisms and predicting response pathways of organisms toward environmental stressors. Herein, we map the spatial location of label-free citrate-coated Ag nanoparticles (Cit-AgNPs) and the corresponding subcellular reorganization in microalgae by a noninvasive 3D imaging approach, cryo-soft X-ray tomography (cryo-SXT). Cryo-SXT near-natively displays the 3D maps of Cit-AgNPs presenting in rarely identified sites, namely, extracellular polymeric substances (EPS) and the cytoplasm. By comparative 3D morphological assay, we observe that Cit-AgNPs disrupt the cellular ultrastructural homeostasis, triggering a severe malformation of cytoplasmic organelles with energy-producing and stress-regulating functions. AgNPs exposure causes evident disruption of the chloroplast membrane, significant attenuation of the pyrenoid matrix and starch sheath, extreme swelling of starch granules and lipid droplets, and shrinkage of the nucleolus. In accompaniment, the number and volume occupancy of starch granules are significantly increased. Meanwhile, the spatial topology of starch granules extends from the chloroplast to the cytoplasm with a dispersed distribution. Linking the dynamics of the internal structure and the alteration of physiological properties, we derive a comprehensive cytotoxic and response pathway of microalgae exposed to AgNPs. This work provides a perspective for assessing the toxicity at subcellular scales to achieve label-free nanoparticle-caused ultrastructure remodeling of phytoplankton.

IRF4 induces M1 macrophage polarization and aggravates ulcerative colitis progression by the Bcl6-dependent STAT3 pathway.

Ulcerative colitis (UC) is an idiopathic chronic intestinal inflammation. An increasing body of evidence shows that macrophages play an important role in the pathogenesis of UC. Interferon regulatory factor 4 (IRF4) is crucial for the development of autoimmune diseases via regulating immune cells. This research was designed to explore the function of IRF4 in UC and its association with macrophage polarization. The in vitro model of UC was established by stimulating colonic epithelial cells with tumor necrosis factor α (TNF-α). A mouse model of UC was constructed by injecting C57BL/6 mice with dextran sulfate sodium salt. Flow cytometry was used to assess percentage of CD11b+ CD86+ and CD11b+ CD206+ cells in bone marrow macrophages. Occult blood tests were used to detect hematochezia. Hematoxylin and eosin staining assay was used to assess colon pathological changes. Enzyme-linked immunosorbent assay (ELISA) was used to detect concentrations of inflammatory cytokines. The interaction of IRF4 and B-cell lymphoma 6 (Bcl6) was confirmed using GST pull-down and coimmunoprecipitation assays. Our findings revealed that IRF4 promoted cell apoptosis and stimulated M1 macrophage polarization in vitro. Furthermore, IRF4 aggravated symptoms of the mouse model of UC and aggravated M1 macrophage polarization in vivo. IRF4 negatively regulated Bcl6 expression. Downregulation of Bcl6 promoted apoptosis and M1 macrophage polarization in the presence of IRF4 in vitro and in vivo. Moreover, Bcl6 positively mediated the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway. In conclusion, IRF4 aggravated UC progression through promoting M1 macrophage polarization via Bcl6/JAK2/STAT3 pathway. These findings suggested that IRF4 might be a good target to competitively inhibit or to treat with UC.

Tumor cells-derived extracellular vesicles carry circ_0064516 competitively inhibit microRNA-6805-3p and promote cervical cancer angiogenesis and tumor growth.

BACKGROUND: The current study tried to elucidate the regulatory role of tumor cell-derived exosomes (Exos)-circ_0064516 in angiogenesis and growth of cervical cancer. RESEARCH DESIGN AND METHODS: Related cirRNAs and downstream target genes were identified through bioinformatics analysis. Exos were isolated from cervical cancer cell line CaSki, followed by co-cultured with human umbilical vein endothelial cells (HUVECs). Then, the roles of circ_0064516, miR-6805-3p, and MAPK1 in migration and angiogenesis of HUVECs were assayed. Furthermore, xenografted tumors were transplanted into nude mice for in vivo validation. RESULTS: In vitro assay validated highly expressed circ_0064516 in cervical cancer cells. Tumor cell-derived Exos carried circ_0064516 to HUVECs. circ_0064516 increased MAPK1 expression by binding to miR-6805-3p, thus enhancing migration and angiogenesis. Exos containing circ_0064516 also promoted tumorigenesis of cervical cancer cells in nude mice. CONCLUSIONS: We confirmed the oncogenic role of tumor cell-derived Exos carrying circ_0064516 in cervical cancer progression through miR-6805-3p/MAPK1.

SRSF7 is a promising prognostic biomarker in hepatocellular carcinoma and is associated with immune infiltration.

BACKGROUND: Previous studies indicate that the splicing process, regulated by the cellular machinery of tumors (spliceosome), undergoes alterations, leading to oncogenic splicing events associated with the progression of tumors towards aggressiveness. However, the role of serine/arginine-rich splicing factor 7 (SRSF7) in hepatocellular carcinoma (HCC) and the tumor microenvironment (TME) remains unclear. METHODS: This study was aimed to explore the role and clinical significance of SRSF7 in HCC. By conducting functional analysis and gene set enrichment analysis, it was discovered that SRSF7 contributes to multiple pathways associated with immune response and tumor advancement. Further experiments verified that silencing of SRSF7 obviously inhibits progression of HCC. RESULTS: Aberrant expression of SRSF7, which were referred as an independent prognostic risk factor, effectively predicts the prognosis of patients with HCC. Functional and gene enrichment analyses revealed that SRSF7 is linked with multiple immune and tumor progression-related pathways, including the B cell receptor signaling pathway, positive regulation of leukocyte and immunoglobulin receptor binding cell activation, nuclear division, membrane invagination, cell cycle, as well as mTOR signaling pathway. Furthermore, increased SRSF7 expression was associated with tumor-infiltrating inflammatory cells (CD4+, monocytes/macrophages, CD8 + and endothelial). Additionally, multiple immune checkpoint genes were markedly positively related to SRSF7. The efficiency of SRSF7 in predicting immunomodulator and chemokine responses were also assessed in microenvironment. Moreover, in vitro analyses demonstrated that knockdown of SRSF7 suppressed the malignant evolution of HCC possibly by deactivating the PI3K/AKT/mTOR signaling. CONCLUSION: The role of SRSF7 in the tumor microenvironment has been successfully assessed. It may be a valid bio-index for predicting the HCC prognosis, thereby guiding individualized immunotherapy for cancer.

CYP1B1-AS1 Delays the Malignant Progression of Colorectal Cancer by Binding with NOP58.

BACKGROUND: Colorectal cancer (CRC) is a prevalent type of gastrointestinal cancer, and its poor prognosis is mainly attributed to the occurrence of invasion and metastasis. CYP1B1-AS1, as non-coding RNA, plays an important role in tumorigenesis and progression. However, the mechanism by which CYP1B1-AS1 acts in CRC is not yet understood. AIMS: The objective of this study was to investigate how CYP1B1-AS1 contributes to the development of CRC, and provide a base for CRC diagnosis and treatment. METHODS: RT-qPCR was used to detect the expression level of CYP1B1-AS1 in CRC and adjacent tissues. CCK-8, Edu, scratch healing, and transwell experiments were used to detect the changes of proliferation, migration, and invasion ability of CRC cells after overexpression or knockdown of CYP1B1-AS1 respectively. The RNA binding protein NOP58 combined with CYP1B1-AS1 was verified by RIP and RNA Pull-down experiments. Functional recovery experiments validated the interaction between CYP1B1-AS1 and NOP58 in CRC cells. The changes of EMT-related proteins were detected by Western blot, and the half-life of transcription factor SNAIL mRNA were detected by RT-qPCR after overexpression or knockdown of NOP58. RESULTS: CYP1B1-AS1 was found to be significantly downregulated in CRC compared to adjacent noncancerous tissues. Experiments conducted in vitro and in vivo confirmed that upregulation of CYP1B1-AS1 significantly inhibited the proliferation, migration, and invasion of CRC cells. In addition, CYP1B1-AS1 can directly bind to NOP58 and negatively regulate NOP58. The effect of overexpression CYP1B1-AS1 was reversed by NOP58 overexpression. NOP58 regulates the EMT process of CRC cells by affecting the stability of EMT-related transcription factor SNAIL mRNA, and then affects the progress of CRC. CONCLUSION: This research proves that CYP1B1-AS1 can inhibit the occurrence of EMT in CRC by binding with NOP58, thus delaying the progress of CRC. This finding indicates that CYP1B1-AS1 may be a novel biomarker to improve the diagnosis and treatment of CRC.

The {Cu2I2} cluster bearing metal organic frameworks: crystal structures and fluorescence detecting performances towards cysteine and explosive molecules.

Two {Cu2I2} cluster-bearing metal organic frameworks (MOFs) of {[Eu(CuI)2(INA)3DMF]·0.95DMF}n (Eu-CuI-INA) and {K[(CH3)2NH2]Sr4(INA)2(DMF)2{(Cu2I2)2(INA)8}·2H2O}n (Sr-K-CuI-INA, HINA = isonicotinic acid, DMF = N,N-dimethyl formamide) were prepared and characterized in this work. Both materials feature a three-dimensional (3-D) structure, in which the {Cu2I2} clusters and Eu3+ (or Sr2+) metal ions are coordinated by INA- ligands with pyridine and carboxylic groups, respectively. Impressively, Sr-K-CuI-INA exhibits sensitive fluorescence sensing behaviors towards cysteine and nitro-bearing molecules, demonstrating potential FL sensing applications for bio and explosive molecules. This work would provide a good reference for designing fluorescent MOF probes containing CuI molecules.

A third (booster) dose of the inactivated SARS-CoV-2 vaccine elicits immunogenicity and T follicular helper cell responses in people living with HIV.

Introduction: This study sought to explore the immunogenicity of a booster dose of an inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine in people living with human immunodeficiency virus (HIV) and identify the factors affecting the magnitude of anti-SARS-CoV-2 antibody levels. Materials and methods: A total of 34 people living with HIV (PLWH) and 34 healthy donors (HD) were administered a booster dose of the same SARS-CoV-2 vaccine. Anti-SARS-CoV-2 antibody and immunoglobulin G (IgG) levels were measured using the SARS-CoV-2 S protein neutralizing antibody Enzyme-Linked Immunosorbent Assay (ELISA) and 2019-nCov IgG Chemiluminescent Immunoassay Microparticles, respectively. Spearman correlation analysis was used to measure the correlation between laboratory markers and neutralizing antibody and IgG levels. Peripheral blood mononuclear cells (PBMCs) were extracted from each subject using density gradient centrifugation and the numbers of memory T and T follicular helper (Tfh) cells were determined using flow cytometry. Results: PLWH had a marked reduction in CD4 and B cell levels that was accompanied by a lower CD4/CD8 T cell ratio. However, those who received a supplementary dose of inactivated SARS-CoV-2 vaccines exhibited antibody positivity rates that were analogous to levels previously observed. The booster vaccine led to a reduction in IgG and neutralizing antibody levels and the amplitude of this decline was substantially higher in the PLWH than HD group. Correlation analyses revealed a strong correlation between neutralizing antibody levels and the count and proportion of CD4 cells. Anti-SARS-CoV-2 IgG antibody levels followed a similar trend. The expression of memory T and Tfh cells was considerably lower in the PLWH than in the HD group. Discussion: PLWH had an attenuated immune response to a third (booster) administration of an inactivated SARS-CoV-2 vaccine, as shown by lower neutralizing antibody and IgG levels. This could be attributed to the reduced responsiveness of CD4 cells, particularly memory T and cTfh subsets. CD4 and cTfh cells may serve as pivotal markers of enduring and protective antibody levels. Vaccination dose recalibration may be critical for HIV-positive individuals, particularly those with a lower proportion of CD4 and Tfh cells.

ProtoCLIP: Prototypical Contrastive Language Image Pretraining.

Contrastive language image pretraining (CLIP) has received widespread attention since its learned representations can be transferred well to various downstream tasks. During the training process of the CLIP model, the InfoNCE objective aligns positive image-text pairs and separates negative ones. We show an underlying representation grouping effect during this process: the InfoNCE objective indirectly groups semantically similar representations together via randomly emerged within-modal anchors. Based on this understanding, in this article, prototypical contrastive language image pretraining (ProtoCLIP) is introduced to enhance such grouping by boosting its efficiency and increasing its robustness against the modality gap. Specifically, ProtoCLIP sets up prototype-level discrimination between image and text spaces, which efficiently transfers higher level structural knowledge. Furthermore, prototypical back translation (PBT) is proposed to decouple representation grouping from representation alignment, resulting in effective learning of meaningful representations under a large modality gap. The PBT also enables us to introduce additional external teachers with richer prior language knowledge. ProtoCLIP is trained with an online episodic training strategy, which means it can be scaled up to unlimited amounts of data. We trained our ProtoCLIP on conceptual captions (CCs) and achieved an + 5.81% ImageNet linear probing improvement and an + 2.01% ImageNet zero-shot classification improvement. On the larger YFCC-15M dataset, ProtoCLIP matches the performance of CLIP with 33% of training time.