Multilayer factors associated with excess all-cause mortality during the omicron and non-omicron waves of the COVID-19 pandemic: time series analysis in 29 countries.

BACKGROUND: The COVID-19 pandemic has resulted in significant excess mortality globally. However, the differences in excess mortality between the Omicron and non-Omicron waves, as well as the contribution of local epidemiological characteristics, population immunity, and social factors to excess mortality, remain poorly understood. This study aims to solve the above problems. METHODS: Weekly all-cause death data and covariates from 29 countries for the period 2015-2022 were collected and used. The Bayesian Structured Time Series Model predicted expected weekly deaths, stratified by gender and age groups for the period 2020-2022. The quantile-based g-computation approach accounted for the effects of factors on the excess all-cause mortality rate. Sensitivity analyses were conducted using alternative Omicron proportion thresholds. RESULTS: From the first week of 2021 to the 30th week of 2022, the estimated cumulative number of excess deaths due to COVID-19 globally was nearly 1.39 million. The estimated weekly excess all-cause mortality rate in the 29 countries was approximately 2.17 per 100,000 (95% CI: 1.47 to 2.86). Weekly all-cause excess mortality rates were significantly higher in both male and female groups and all age groups during the non-Omicron wave, except for those younger than 15 years (P < 0.001). Sensitivity analysis confirmed the stability of the results. Positive associations with all-cause excess mortality were found for the constituent ratio of non-Omicron in all variants, new cases per million, positive rate, cardiovascular death rate, people fully vaccinated per hundred, extreme poverty, hospital patients per million humans, people vaccinated per hundred, and stringency index. Conversely, other factors demonstrated negative associations with all-cause excess mortality from the first week of 2021 to the 30th week of 2022. CONCLUSION: Our findings indicate that the COVID-19 Omicron wave was associated with lower excess mortality compared to the non-Omicron wave. This study's analysis of the factors influencing excess deaths suggests that effective strategies to mitigate all-cause mortality include improving economic conditions, promoting widespread vaccination, and enhancing overall population health. Implementing these measures could significantly reduce the burden of COVID-19, facilitate coexistence with the virus, and potentially contribute to its elimination.

Dynamic change, influencing factors, and clinical impact of cellular components in human breast milk.

BACKGROUND: Numerous cellular components have been well demonstrated in human breast milk. However, little is known about their dynamic change, influencing factors, and potential clinical impacts on infants. METHODS: Sixty and forty-five healthy mother-infant pairs were enrolled in the colostrum group and mature milk group, respectively. Participants' demographic and clinical information were collected by questionnaires, and the infants were followed up until 6 months after birth through telephone interview. Colostrum and mature milk were collected, and the percentage of various cell components were determined by flow cytometric analysis. RESULTS: The results showed that, the total cell numbers, and the percentages of some stem cells, including CD34+, CD117+, CD133+, CD90+, CD105+, and CD146+ cells, were different in colostrum and mature milk. Besides, participants' characteristics had influence on the cellular components. Finally, high-CD34+ cells in colostrum, as well as the high-CD133+ cells and low-CD105+ cells in mature milk were associated with a significantly increased risk of infantile eczema within their first 3 months after birth. CONCLUSIONS: Our data showed a dynamic change of cellular components, identified some of their influencing factors and their potential clinical impacts on infantile eczema, which helps to better understand the cellular components in human breast milk. IMPACT: Some stem cell markers were dynamically changed in human colostrum and mature milk. Different cellular components were shown to be influenced by different participants' characteristics. High percentage of CD34+ cells in colostrum, as well as high percentage of CD133+ cells and low percentage of CD105+ cells in mature milk, were associated with a significantly increased risk of infantile eczema within their first 3 months after birth. To our knowledge, this is the first study on the clinical impacts of stem cells on infantile diseases, which helps to give a better understanding of human breast milk.

The plasma levels of Dickkopf-1 elevated in patients with Juvenile Idiopathic Arthritis.

BACKGROUND: To explore the role of two major inhibitors of Wnt signal pathway, Dickkopf-1(DKK-1) and Sclerostin (SOST), in the pathogenesis of juvenile idiopathic arthritis (JIA). METHODS: 88 patients with JIA, which including 49 patients with enthesitis-related arthritis (ERA), 21 oligoarthritis (oJIA) and 18 polyarthritis (pJIA), and 36 age-and sex-matched children as healthy controls (HC) were enrolled in this study. The plasma levels of DKK-1 and SOST, measured using commercially available ELISA kits, were analyzed the correlation between the levels of DKK-1/SOST and JIA, and were analyzed in 14 patients with JIA during before and after treatment. RESULTS: Plasma levels of DKK-1 were significantly higher in the patients with JIA than that in HC, the elevation of DKK-1 level was positively correlated with HLA-B27 positive JIA. DKK-1 levels dropped significantly in patient with JIA after treatment (P < 0.05). There was no significant change in SOST levels among different subtypes of JIA, patients with JIA during before and after treatment, and HC. CONCLUSION: It was suggested that the DKK-1 may have a certain correlation with the pathogenesis of JIA, and DKK-1 levels are more closely related to the HLA-B27 positive-ERA. IMPACT: The abnormally elevated levels of Dickkopf-1 (DKK-1) may be involved in the pathogenesis of juvenile idiopathic arthritis (JIA). DKK-1 levels were more closely related to the HLA-B27 positive-enthesitis-related arthritis (ERA). DKK-1 is an inhibitor of Wnt signaling pathway that promotes osteoblastic new bone formation; it is very rare for pediatric patients with HLA-B27 positive-ERA to manifest typical spondylitis, while sacroiliac arthritis is relatively common, which may be related to the high levels of DKK-1, which is consistent with the early stage of ankylosing spondylitis (AS).

Correlations of GGT, Hcy and ABI with carotid atherosclerosis in essential hypertension patients.

This study was to explore the correlations of glutamyltransferase (GGT), homocysteine (Hcy) and ankle-brachial index (ABI) with the onset of cervical atherosclerosis (CAS) in essential hypertension (EH) patients. For this purpose, a total of 280 EH patients who were admitted to this hospital or visited the clinic of this hospital were enrolled into the EH group and received the color Doppler ultrasound for carotid artery and biochemical test for blood, and according to the plaques, they were divided into three groups: non-plaque group (n = 113), stable plaque group (n = 102) and non-stable plaque group (n = 65). Simultaneously, 80 healthy subjects who underwent the physical examination were enrolled in the control group. Correlations of GGT, Hcy and ABI with the onset of CAS were analyzed. The results indicated that in the EH group, the prevalence of CAS and Hcy levels were all higher than those in the control group (all P<0.05). As compared to the non-plaque group, patients with stable or non-stable plaques had higher levels of GGT and Hcy in serum but lower levels of ABI (all P<0.05). Logistic regression analysis revealed that CAS plaques were in positive correlation with the levels of GGT and Hcy in serum, but in negative correlation with ABI (P<0.05). In conclusion, ABI is the protective factor of CAS in EH patients, while Hcy and GGT are the negative factors.

Willingness to practice medicine and related influential factors among medical undergraduates during COVID-19: a cross-sectional study.

BACKGROUND: As the medical undergraduates constitute the future workforce in China, their career preferences hold a significant bearing on the quality of healthcare services, particularly in light of the ongoing COVID-19 pandemic. We aim to understand the current state of the willingness to practice medicine among medical undergraduates and to analyze the related influential factors. METHODS: During the COVID-19 epidemic, we conducted a cross-sectional survey via an online platform from February 15, 2022, to May 31, 2022, to collect participants' demographic information, psychology, and factors influencing their career choices. The general self-efficacy scale (GSES) was used to evaluate medical students' perceptions of their self-efficacy. Futhermore, we conducted multivariate logistic regression analyses to explore the influencing factors of medical undergraduates' willingness to pursure a caree in medicine. RESULTS: A total of 2348 valid questionnaires were included, and 1573 (66.99%) were willing to practice medicine for medical undergraduates after graduation. The mean GESE scores in the willingness group (2.87 ± 0.54) were significantly higher than those of the unwillingness group (2.73 ± 0.49). The multiple logistic regression showed that several factors were positively associated with willingness to practice medicine as a career, including students' GSES score (OR = 1.87), current major, household income, personal ideals (OR = 1.97), family support (OR = 1.44), high income (OR = 1.77), and social respect (OR = 2.19). Compared with those who were very afraid of COVID-19, students who did not express any fear towards the COVID-19 pandemic had a higher preference for choosing the medical profession as a career. Conversely, students thinking of high tension in the doctor-patient relationship, heavy workload, and long training were less likely to choose medical work after graduation. CONCLUSIONS: The study highlights a noteworthy prevalence of medical undergraduates who expressed their willingness to pursue medicine as a career post-graduation. Several factors, including but not limited to current major, household income, psychological factors, personal preferences, and career needs or preferences, were significantly associated with this willingness. Moreover, the impact of the COVID-19 pandemic on medical students' career choices cannot be overlooked.

Tachykinin Neuropeptides and Amyloid ß (25-35) Assembly: Friend or Foe?

Amyloid ß (Aß) protein is responsible for Alzheimer's disease, and one of its important fragments, Aß(25-35), is found in the brain and has been shown to be neurotoxic. Tachykinin neuropeptides, including Neuromedin K (NK), Kassinin, and Substance P, have been reported to reduce Aß(25-35)'s toxicity in cells even though they share similar primary structures with Aß(25-35). Here, we seek to understand the molecular mechanisms of how these peptides interact with Aß(25-35) and to shed light on why some peptides with similar primary structures are toxic and others nontoxic. We use both experimental and computational methods, including ion mobility mass spectrometry and enhanced-sampling replica-exchange molecular dynamics simulations, to study the aggregation pathways of Aß(25-35), NK, Kassinin, Substance P, and mixtures of the latter three with Aß(25-35). NK and Substance P were observed to remove the higher-order oligomers (i.e., hexamers and dodecamers) of Aß(25-35), which are related to its toxicity, although Substance P did so more slowly. In contrast, Kassinin was found to promote the formation of these higher-order oligomers. This result conflicts with what is expected and is elaborated on in the text. We also observe that even though they have significant structural homology with Aß(25-35), NK, Kassinin, and Substance P do not form hexamers with a ß-sheet structure like Aß(25-35). The hexamer structure of Aß(25-35) has been identified as a cylindrin, and this structure has been strongly correlated to toxic species. The reasons why the three tachykinin peptides behave so differently when mixed with Aß(25-35) are discussed.

Kikuchi-Fujimoto disease as the initial manifestation of systemic lupus erythematosus complicated with macrophage activation syndrome: two case reports and a review of literature.

BACKGROUND: Kikuchi-Fujimoto disease (KFD) is a self-limiting and benign disease characterized by cervical lymphadenopathy and fever. Although KFD should be made differentially diagnosed from infectious, autoimmune, and malignant diseases, it sometimes occurs in patients with systemic lupus erythematosus (SLE) and can be complicated with macrophage activation syndrome (MAS). However, it is rare that KFD is the initial manifestation of SLE and to be complicated with MAS. CASE PRESENTATION: A 9.6-year-old girl presented with high-grade fever, double-side cervical lymphadenopathy with mild pain of one week, leukopenia, alopecia, and rash on the cheek. During hospitalization, laboratory investigations showed positive antinuclear antibody (ANA), low complement 3 (C3), and low complement 4 (C4). Imaging investigations showed pleural and pericardial effusion. A 10.3-year-old girl presented with intermittent high-grade fever, double-sided cervical lymphadenopathy with obvious pain of 1-month duration, and discoid lesion on the cheek. During hospitalization, laboratory investigations showed positive ANA, leukopenia, thrombocytopenia, anemia with positive Coombs' test, low C3, and positive Smith antibodies. Both cases were diagnosed with KFD using lymph node biopsy, simultaneously fulfilling the diagnostic criteria of SLE. Subsequently, the two girls became complicated with MAS, followed by interstitial lung disease and neuropsychiatric lupus, respectively. Both patients benefited from high-dose methylprednisolone pulse therapy combined with intravenous cyclophosphamide. CONCLUSIONS: More attention should be paid to differential diagnosis, especially SLE, in children diagnosed with KFD. In addition, children with SLE who presented with KFD as the initial manifestation seem to have a higher risk of developing MAS and experiencing organ involvement.

Batch Fabrication of High-Quality Infrared Chalcogenide Microsphere Resonators.

Optical microsphere resonators working in the near- and mid-infrared regions are highly required for a variety of applications, such as optical sensors, filters, modulators, and microlasers. Here, a simple and low-cost approach is reported for batch fabrication of high-quality chalcogenide glass (ChG) microsphere resonators by melting high-purity ChG powders in an oil environment. Q factors as high as 1.2 × 106 (7.4 × 105 ) are observed in As2 S3 (As2 Se3 ) microspheres (≈30 µm in diameter) around 1550-nm wavelength. Smaller microspheres with sizes around 10 µm also show excellent resonant responses (Q ≈ 2.5 × 105 ). Based on the mode splitting of an azimuthal mode in a microsphere resonator, eccentricities as low as ≈0.13% (≈0.17%) for As2 S3 (As2 Se3 ) microspheres are measured. Moreover, by coupling ChG microspheres with a biconical As2 S3 fiber taper, Q factors of ≈1.7 × 104 (≈1.6 × 104 ) are obtained in As2 S3 (As2 Se3 ) microspheres in the mid-infrared region (around 4.5 µm). The high-quality ChG microspheres demonstrated here are highly attractive for near- and mid-infrared optics, including optical sensing, optical nonlinearity, cavity quantum electrodynamics, microlasers, nanofocusing, and microscopic imaging.

Polystyrene nanoparticles induced neurodevelopmental toxicity in Caenorhabditis elegans through regulation of dpy-5 and rol-6.

Micro- and nano- polystyrene particles have been widely detected in environment, posing potential threats to human health. This study was designed to evaluate the neurodevelopmental toxicity of polystyrene nanoparticles (NPs) in Caenorhabditis elegans (C. elegans), to screen crucial genes and investigate the underlying mechanism. In wild-type C. elegans, polystyrene NPs (diameter 50 nm) could concentration-dependently induce significant inhibition in body length, survival rate, head thrashes, and body bending, accompanying with increase of reactive oxygen species (ROS) production, lipofuscin accumulation, and apoptosis and decrease of dopamine (DA) contents. Moreover, pink-1 mutant was demonstrated to alleviate the locomotion disorders and oxidative damage induced by polystyrene NPs, indicating involvement of pink-1 in the polystyrene NPs-induced neurotoxicity. RNA sequencing results revealed 89 up-regulated and 56 down-regulated differently expressed genes (DEGs) response to polystyrene NPs (100 µg/L) exposure. Gene Ontology (GO) enrichment analysis revealed that predominant enriched DEGs were correlated with biological function of cuticle development and molting cycle. Furthermore, mutant strains test showed that the neurodevelopmental toxicity and oxidative stress responses induced by 50 nm polystyrene NPs were regulated by dpy-5 and rol-6. In general, polystyrene NPs induced obvious neurodevelopmental toxicity in C. elegans through oxidative damage and dopamine reduction. Crucial genes dpy-5 and rol-6 might participate in polystyrene NPs-induced neurodevelopmental toxicity through regulation on synthesis and deposition of cuticle collagen.

Genome-Wide Identification and Characterization of Wheat 14-3-3 Genes Unravels the Role of TaGRF6-A in Salt Stress Tolerance by Binding MYB Transcription Factor.

14-3-3 proteins are a large multigenic family of general regulatory factors (GRF) ubiquitously found in eukaryotes and play vital roles in the regulation of plant growth, development, and response to stress stimuli. However, so far, no comprehensive investigation has been performed in the hexaploid wheat. In the present study, A total of 17 potential 14-3-3 gene family members were identified from the Chinese Spring whole-genome sequencing database. The phylogenetic comparison with six 14-3-3 families revealed that the majority of wheat 14-3-3 genes might have evolved as an independent branch and grouped into ε and non-ε group using the phylogenetic comparison. Analysis of gene structure and motif indicated that 14-3-3 protein family members have relatively conserved exon/intron arrangement and motif composition. Physical mapping showed that wheat 14-3-3 genes are mainly distributed on chromosomes 2, 3, 4, and 7. Moreover, most 14-3-3 members in wheat exhibited significantly down-regulated expression in response to alkaline stress. VIGS assay and protein-protein interaction analysis further confirmed that TaGRF6-A positively regulated slat stress tolerance by interacting with a MYB transcription factor, TaMYB64. Taken together, our findings provide fundamental information on the involvement of the wheat 14-3-3 family in salt stress and further investigating their molecular mechanism.

Chlorin e6-Biotin Conjugates for Tumor-Targeting Photodynamic Therapy.

To improve the tumor-targeting efficacy of photodynamic therapy, biotin was conjugated with chlorin e6 to develop a new tumor-targeting photosensitizer, Ce6-biotin. The Ce6-biotin had good water solubility and low aggregation. The singlet-oxygen generation rate of Ce6-biotin was slightly increased compared to Ce6. Flow cytometry and confocal laser scanning microscopy results confirmed Ce6-biotin had higher binding affinity toward biotin-receptor-positive HeLa human cervical carcinoma cells than its precursor, Ce6. Due to the BR-targeting ability of Ce6-biotin, it exhibited stronger cytotoxicity to HeLa cells upon laser irradiation. The IC50 against HeLa cells of Ce6-biotin and Ce6 were 1.28 µM and 2.31 µM, respectively. Furthermore, both Ce6-biotin and Ce6 showed minimal dark toxicity. The selectively enhanced therapeutic efficacy and low dark toxicity suggest that Ce6-biotin is a promising PS for BR-positive-tumor-targeting photodynamic therapy.

Anti-HER2 Affibody-Conjugated Photosensitizer for Tumor Targeting Photodynamic Therapy.

Antibody-coupled photosensitive molecules can achieve an ideal tumor-specific photodynamic therapy (PDT) and show strong clinical application potential. However, some inherent disadvantages, such as long circulation half-life, poor permeation into solid tumors, and difficulty in obtaining uniform coupling products, present potential problems to clinical applications. In this study, we propose a novel design of targeting photosensitizers, based on a very small targeting protein (an affibody molecule) coupled with photosensitive compounds, to address these problems. In the synthesis, photosensitive pyropheophorbide-a (Pyro) is modified with a PEG linker (molecular weight of 727 Da) and then site specifically coupled to the anti-HER2 ZHER2:2891 affibody protein to provide a homogeneous protein-coupled photosensitizer via a convenient process. In vitro and in vivo experiments show that this molecule has an ideal selectivity for binding and photocytotoxicity against HER2-positive cells (more than 50-fold selectivity between HER2-high expression and HER2-low expression cells) and highly specific tumor accumulation; at a relatively low dose, it effectively eliminated HER2-high expression NCI-N87 tumors in a mouse model. It is worth noting that Pyro only has a moderate photodynamic activity; however, the affibody-coupled Pyro molecule (Pyro-Linker-ZHER2) still shows excellent tumor therapeutic function. The more ideal tumor permeability of small ligands may be helpful to enhance the drug concentration in the tumor site and the ability to penetrate deeply inside the tumor. Coupling photosensitive compounds with affibody proteins may provide a new way for targeting PDT of tumors.

Association of Tim-4 expression in monocyte subtypes with clinical course and prognosis in acute ischemic stroke patients.

Background: It has been proven that T cell immunoglobin and mucin domain (Tim)-4 and monocytes (Mo) are involved in regulation of immunity, which is important for the recovery of acute ischemic stroke (AIS).Methods: In this study, the expression of Tim-4 in both circulating Mo subtypes and plasma in 32 consecutive AIS patients and 32 control patients was assessed to determine their correlation with the clinical course and prognosis of AIS.Results: It was found that, compared to the control patients, the percentage of Tim-4 expression in overall Mo, classical Mo and non-classical Mo was significantly elevated after 2 and 5 days of stroke (p < 0.05), while it was promoted from 0 to 10 days of stoke in intermediate Mo (p < 0.05). Furthermore, Tim-4 expressions in non-classical Mo and intermediate Mo were obviously correlated with National Institutes of Health Stroke Scale (NIHSS) scores at 2 days of stroke (r = 0.351, p = 0.048; r = 0.358, p = 0.044, respectively). In poor outcome (PO) patients, the expression of Tim-4 in non-classical Mo was remarkably promoted at 2 days of stroke in comparison with non-PO patients (p < 0.05). More importantly, our results revealed a positive correlation between Tim-4 expression in non-classical Mo and interleukin (IL)-6 plasma levels in AIS patients without infection.Conclusion: In summary, our findings proved that Tim-4 expression in non-classical Mo could be an appropriate target for the prediction of the clinical course and prognosis in AIS patients.

The miRNA hsa-miR-6515-3p potentially contributes to lncRNA H19-mediated-lung cancer metastasis.

Aberrant expression of long noncoding RNAs (lncRNAs) contributes to all phenotypes of cancer including metastasis, which is a major cause of death in many advanced malignancies. One particular lncRNA, H19, is found to be a crucial player in cancer progression by modulating multiple microRNAs (miRNAs). In this study, we screened miRNAs possibly associated with H19 using lung carcinoma cell lines and patient with lung cancer tissues, and selected one possible hit, hsa-miR-6515-3p, to perform in vitro functional assays. Its inhibition leads to decreased proliferation and migration of SPC-A1 lung cancer cells and is in good correlation with H19-knockdown groups. These results indicate that H19 may be an epigenetic regulator of miR-6515-3p, and its dysregulation may contribute to lung cancer progression and metastasis.

Indole-Fused Acridone: Synthesis, Structures, Proton Transfer, and Hole-Transport Properties.

Three pairs of regioisomers of the planar acridone derivatives (9 vs 10, 11 vs 12, and 13 vs 14), classified as the 1-cyclized compounds (9, 11, and 13) and the 3-cyclized (or 1,3'-cyclized) regioisomers (10, 12, and 14), have been synthesized, and their X-ray structures have been determined. The 1-cyclized compounds have higher yields and lower energies compared with their 3-cyclized isomers. The fluorescence spectra of the intramolecular H-bond containing compounds (9, 11, 13, and 14) consist of two bands (shorter wavelength band for the keto form and longer wavelength band for the enol form) and exhibit the feature of the excited-state intramolecular proton transfer (ESIPT). The density functional theory (DFT) theoretical investigation of the reorganization energy (λ) with respect to molecular symmetry revealed that planar rigid- C2 v-symmetric polycyclic heteroaromatic molecules (such as acridone, 1, and 13) can have low charge-transport barrier (small λ value) and keep the invariance of the molecular point group in the charge-transport process, and therefore can have high hole mobility.

Simvastatin inhibits the development of radioresistant esophageal cancer cells by increasing the radiosensitivity and reversing EMT process via the PTEN-PI3K/AKT pathway.

Acquired radioresistance compromises the efficacy of radiotherapy for carcinomas including esophageal cancer (EC), thus resulting in recurrence and poor survival. Recent research corroborated radiosensitive function of simvastatin in stem-like breast cancer cells. However, its role in EC radioresistance remains poorly elucidated. Here, we developed a radioresistant EC cell line Ec9706-R with higher resistance to irradiation relative to control Ec9706 cells. Intriguingly, Ec9706-R cells exhibited epithelial-mesenchymal transition (EMT) characteristics with high invasion and migration ability. Simvastatin sensitized radioresistance of Ec9706-R cells and suppressed cell proliferation, but aggravated radiation-induced apoptosis and caspase-3 activity. Furthermore, simvastatin reversed EMT and inhibited cell invasion and migration of Ec9706-R cells. Mechanism assay confirmed the activation of PI3K/AKT pathway after radiation, which was inhibited by simvastatin. After restoring this pathway by its activator, IGF-1, simvastatin-mediated radiosensitivity and EMT reversion were abrogated. Further assay substantiated the PTEN suppression after irradiation, which was elevated following simvastatin pre-treatment. Moreover, PTEN cessation attenuated the inhibitory effect of simvastatin on PI3K/AKT activation, and subsequently antagonized simvastatin-induced radiosensitivity and EMT reversion. Additionally, simvastatin aggravated radiation-mediated Ec9706-R tumor growth inhibition. Together, simvastatin inhibits the development of Ec9706-R cells by increasing radiosensitivity and reversing EMT via PTEN-PI3K/AKT pathway, implying a promising strategy against EC radioresistance.

Hexabromocyclododecanes promoted autophagy through the PI3K/Akt/mTOR pathway in L02 cells.

As additive brominated flame retardants, hexabromocyclododecanes (HBCDs) are being widely used in diverse artificial materials and products, including thermal insulation building materials, housings of electronic equipment, and upholstery textiles. Toxicology studies have shown that HBCDs exposure are closely related to hepatotoxicity and liver diseases. The present study is designed to explore how HBCDs affect cell apoptosis and autophagy process in a human hepatocyte cell line (L02) and to reveal the underline molecular mechanisms. Firstly, HBCDs could elevate the apoptosis rate of L02 cells dose-dependently. Three apoptosis related proteins (apoptotic protease activating factor 1 (Apaf-1), cysteinyl aspartate specific proteinase 3 (caspase-3) and cysteinyl aspartate specific proteinase 9 (caspase-9)) were observed to be up-regulated using western blotting method. Autophagy process was also started by HBCDs in L02 cells as indicated by the increased expressions of LC3-phosphatidylethanolamine conjugate (LC3-II) and other autophagic protein markers (Beclin-1, autophagy related protein 3 (Atg3), autophagy related protein 5 (Atg5), autophagy related protein 7 (Atg7) and autophagy related protein 16L1(Atg16L1)). The results of the green fluorescent protein (GFP)-microtubule-associated protein 1 light chain 3 (LC3) intracellular localization and fluorescence intensity further evidenced the activation of autophagy in L02 cells after treated with HBCDs. In addition, phosphatidylinositide 3-kinases/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway was activated in L02 cells by HBCDs, suggested by the increased expressions of related proteins. The inhibitors of PI3K (LY294002), DNA-activated protein kinase catalytic subunit (DNA-PKcs) (NU7441), Akt (MK2206), and mTOR (KU0063794) could obviously reduce the autophagic proteins prompted by HBCDs. The fluorescence intensities of GFP-LC3 transfected L02 cells were also decreased significantly after the application of these inhibitors. These results indicated that PI3K/Akt/mTOR pathway was participated in regulating autophagy process promoted by HBCDs. In above, HBCDs could induce mitochondrial-dependent apoptosis and autophagy in L02 cells, which was modulated by PI3K/Akt/mTOR pathway.

Multimerization Increases Tumor Enrichment of Peptide⁻Photosensitizer Conjugates.

Photodynamic therapy (PDT) is an established therapeutic modality for the management of cancers. Conjugation with tumor-specific small molecule ligands (e.g., short peptides or peptidomimetics) could increase the tumor targeting of PDT agents, which is very important for improving the outcome of PDT. However, compared with antibody molecules, small molecule ligands have a much weaker affinity to their receptors, which means that their tumor enrichment is not always ideal. In this work, we synthesized multimeric RGD ligand-coupled conjugates of pyropheophorbide-a (Pyro) to increase the affinity through multivalent and cluster effects to improve the tumor enrichment of the conjugates. Thus, the dimeric and trimeric RGD peptide-coupled Pyro conjugates and the monomeric one for comparison were efficiently synthesized via a convergent strategy. A short polyethylene glycol spacer was introduced between two RGD motifs to increase the distance required for multivalence. A subsequent binding affinity assay verified the improvement of the binding towards integrin αvß3 receptors after the increase in the valence, with an approximately 20-fold improvement in the binding affinity of the trimeric conjugate compared with that of the monomeric conjugate. In vivo experiments performed in tumor-bearing mice also confirmed a significant increase in the distribution of the conjugates in the tumor site via multimerization, in which the trimeric conjugate had the best tumor enrichment compared with the other two conjugates. These results indicated that the multivalence interaction can obviously increase the tumor enrichment of RGD peptide-conjugated Pyro photosensitizers, and the prepared trimeric conjugate can be used as a novel antitumor photodynamic agent with high tumor enrichment.

[THAP11 mediates the proliferation and apoptosis of esophageal cancer cells via inhibiting ubiquitination of p53].

OBJECTIVE: To investigate the effects of thanatos-associated protein 11 (THAP11) on the proliferation and apoptosis of esophageal cancer cell and the underlying mechanism.
 Methods: Expression of THAP11 in human esophageal epithelial cells (Het-1A) and esophageal cancer cells (Eca109, TE-1, Ec 9706) were detected by Western blotting. Esophageal cancer TE-1 cells were divided into 3 groups: a normal control (NC) group, a negative control (LV-NC) group and a THAP11 (LV-THAP11) group. Then the cell proliferation were detected by MTT assay, cell apoptosis were detected by flow cytometry, caspase-3 and caspase-9 levels were detected by caspases kits. Ubiquitination of p53 was determined in esophageal cancer TE-1 cells.
 Results: Expression of THAP11 was reduced in esophageal cancer cells compared with human esophageal epithelial cells (P<0.05). After transfection with LV-THAP11 in TE-1 cells, cell viability was reduced (P<0.05), while apoptosis rate and caspase-3 and caspase-9 levels were increased (P<0.05), indicating that THAP11 inhibited growth of esophageal cancer cells. In addition, the THAP11 increased the levels of p53 (P<0.05) and inhibited the ubiquitination of p53 regulated by MDM2. 
 Conclusion: THAP11 may inhibit the proliferation of esophageal cancer cells by inhibiting ubiquitination of p53.