Endoplasmic reticulum targeted fluorescent probe for real-time monitoring the viscosity changes induced by calcium homeostasis disruption

The endoplasmic reticulum (ER) acts as the major storage site for calcium ions, which are messenger ions for intracellular signaling. Disruption of calcium ion homeostasis can significantly affect the viscosity, polarity and pH of the ER. However, it is still unclear the relationship between the viscosity changes in ER and the imbalance of calcium ion homeostasis. Herein, we developed a novel fluorescent probe, named TPA, for monitoring viscosity changes that specifically targets the endoplasmic reticulum rather than mitochondria or lysosomes. TPA probe displayed good stability, as well as high responsiveness and selectivity to viscosity. The fluorescence intensity of TPA was significantly enhanced with the increased concentration or incubation time of the stimulating agents(i.e., tunicamycin), showing high responsiveness to the viscosity changes in ER. Furthermore, the TPA probe successfully demonstrated that an increase in intracellular calcium ion concentration leads to an increase in ER viscosity, whereas a decrease in calcium ion concentration leads to a decrease viscosity in ER. Both in vitro and in vivo experiments demonstrated that TPA probe successfully detected the viscosity changes in ER, especially the effects of calcium ion homeostasis disruption on ER. Overall, the TPA probe represents an efficient method for studying the relationship between calcium ion homeostasis and ER viscosity.

Monitoring the Mitochondrial Viscosity Changes During Cuproptosis with Iridium(III) Complex Probe via In Situ Phosphorescence Lifetime Imaging

Cuproptosis is a novel copper-dependent form of programmed cell death, displaying important regulatory functions in many human diseases, including cancer. However, the relationship between the changes in mitochondrial viscosity, a key factor associated with cellular malfunction, and cuproptosis is still unclear. Herein, we prepared a phosphorescent iridium (Ir) complex probe for precisely monitoring the changes of mitochondrial viscosity during cuprotosis via phosphorescence lifetime imaging. The Ir complex probe possessed microsecond lifetimes (up to 1 μs), which could be easily distinguished from cellular autofluorescence to improve the imaging contrast and sensitivity. Benefiting from the long phosphorescence lifetime, excellent viscosity selectivity, and mitochondrial targeting abilities, the Ir complex probe could monitor the increase in the mitochondrial viscosity during cuproptosis (from 46.8 to 68.9 cP) in a quantitative manner. Moreover, through in situ fluorescence imaging, the Ir complex probe successfully monitored the increase in viscosity in zebrafish treated with lipopolysaccharides or elescolomol-Cu2+, which were well-known cuproptosis inducers. We anticipate that this new Ir complex probe will be a useful tool for in-depth understanding of the biological effects of mitochondrial viscosity during cuproptosis.

A "turn-on" red cyclometalated iridium (III) complex for long-term tracking the diffusion of CORM-2 in cells and zebrafish

Transition metal carbonyl compound of CO releasing molecules (CORMs) are widely used to treat arthritis, tumor and immune. They play a physiological role by directly acting on target tissues to release CO for disease treatment without matrix metabolism after dissolution. It is important to track the level and diffusion process of CORMs in vivo to control CO dose and distribution, facilitating to understand the roles of CORMs in disease treatment. Herein, we designed two red ring Ir1/2 complexes with a large stokes shift. Both Ir1 and Ir2 complexes probes can sensitively and selectively respond to CORM-2. The probe Ir1 exhibits rapid reaction with CORM-2 in Phosphate Buffered Saline within 1 min, showing a detection limitation of 0.13 μM and manifesting a linear relationship with the CORM-2 concentration from 0 to 70 μM at λem = 618 nm. Due to low toxicity even after 12 h exposure and fluorescence stability, this probe has been successfully used for continuous tracking the diffusion process of CORM-2 in living cells for up to 60 min and visualizing CORM-2 distribution in zebrafish. Additionally, this probe showed a good capacity for deep penetration (126 μm), suggesting the potential in detecting CORM-2 in living tissues.

[Epidemiological investigation of constipation in urban areas of Hangzhou, China]

Objective: To determine the prevalence and risk factors of constipation in Hangzhou urban areas by analyzing data from a recent epidemiological survey. Methods: From August 2022 to June 2023, a cross-sectional survey was conducted on 43 communities on eight streets in suburbs of Hangzhou, including Wangjiang, Sijiqing, Puyan, Changhe, Ziyang, Xiaoshanchengxiang, Zhuantang, and Banshan. Written questionnaires were filled out face to face by community doctors. The prevalence of constipation was investigated using a combination of the Bristol stool typing method and the Rome IV criteria. The risk factors for constipation were analyzed using multivariate logistic regression analysis. Results: The study cohort comprised 10,479 participants, 5551 of whom were male (53.0%) and 4928 female (47.0%). The overall prevalence of constipation was 10.6% (1107/10,479). The prevalence was 11.0% (613/5551) for male and 10.0% (494/4928) for female participants; this difference is not statistically significant (P>0.05).There were no significant differences in the prevalence of constipation between different categories of body mass index (P>0.05). The prevalence of constipation was highest in individuals aged 70 years and above, accounting for 15.4% (264/1717) of all cases. There were significant differences in the prevalence of constipation between different occupations, marital statuses, and educational levels (P<0.001). Patients with hypertension or diabetes mellitus had a higher prevalence of constipation than those without these conditions, those who had been taking long-term medication had a higher prevalence of constipation than those who did not, parents of children with constipation had a higher prevalence of constipation than those with children who did not have constipation, and there were other significant differences in various variables (P<0.001). Multivariate logistic regression analysis of modifiable factors revealed that eating less fruit (OR=1.284, 95%CI: 1.061-1.553, P=0.010), liking spicy and salty food (OR=1.234, 95%CI: 1.039-1.466, P=0.016), sleeping for too long (OR=1.644, 95%CI: 1.260-2.144, P<0.001), irregular sleep patterns (OR=1.370, 95%CI: 1.127-1.665, P=0.002) and minimal exercise (OR=1.388, 95% CI: 1.168-1.649, P<0.001) were all risk factors for constipation; whereas mix diets (OR=0.709,95%CI:0.608-0.826, P<0.001), meat diets (OR=0.604,95%CI: 0.495-0.736, P<0.001), moderate alcohol consumption (OR=0.659, 95% CI: 0.534-0.812, P<0.001), less or no drinking (OR=0.523, 95% CI: 0.428-0.638, P<0.001), and non-smoking (OR=0.819, 95%CI:0.674-0.995, P<0.001) protected against constipation. We found no association between dietary preferences and the risk of constipation (refined grains: OR=1.147, 95%CI:0.944-1.393, P=0.167; no specific preference: OR=0.935, 95%CI:0.783-1.117, P=0.459). The rate of agreement between self-evaluation of constipation by the respondents and objective criteria was higher for negatives (95.8%) than for positives (38.0%). Conclusion: The prevalence of constipation is relatively high in the urban population of Hangzhou. A good lifestyle and diet can significantly reduce its incidence. There should be more emphasis on preventive education, promotion of prevention of constipation, and advocacy for a healthy lifestyle.

Boric acid group-functional ruthenium complex as a novel fluorescence probe for robust detection of propyl gallate and tert-butyl hydroquinone by tuning the pH

This study reported a ruthenium complex-based fluorescence probe, achieving rapid and sequential detection of propyl gallate (PG) and tert-butyl hydroquinone (TBHQ) for the first time by tuning pH only. Under 480 nm excitation, probe exhibited intensive emission at 620 nm, which was selectively quenched by PG at pH 7.0 due to the covalent binding between the boric acid of probe and o-diphenol hydroxyl of PG. Then pH was tuned to 7.4, the emission was significantly quenched by TBHQ because of the π-π stacking between aromatic rings of probe and paraquinone of TBHQ. This probe realized specific and sensitive detection of PG and TBHQ with wide range and low detection limit (0.26 µM for PG and 0.66 µM for TBHQ). Furthermore, a portable visual test paper detection platform was built based on this probe for rapid and sensitive detection of antioxidants in food, which was of great significance for market regulation.

Comparative analysis of chloroplast genomes of endangered heterostylous species Primula wilsonii and its closely related species

Primula, well known for its heterostyly, is the largest genus in the family Primulaceae with more than 500 species. The considerable species number has introduced a huge challenge for taxonomy. The phylogenetic relationships among Primula still maintain unresolved due to frequent hybridization and introgression between closely related species. In this study, we sequenced and assembled the complete chloroplast genomes of Primula wilsonii Dunn, which is a PSESP (plant species with extremely small populations), using Illumina sequencing and compared its genomic sequences with those of four related Primula species. The chloroplast genomes of Primula species were similar in the basic structure, gene order, and GC content. The detected 38 SSRs (simple sequence repeats) loci and 17 hypervariable regions had many similarities in P. wilsonii, P. anisodora, P. miyabeana, and P. poissonii, but showed a significant difference compared with those in P. secundiflora. Slight variations were observed among Primula chloroplast genomes, in consideration of the relatively stable patterns of IR (inverted repeats) contraction and expansion. Phylogenetic analysis based on chloroplast genomes and protein-coding genes confirmed three major clades in Chinese Primula, but the infrageneric sections were not in accordance with morphological traits. The P. poissonii complex was confirmed here and P. anisodora was the most closely related species to P. wilsonii. Overall, the chloroplast genome sequences provided useful genetic and evolutionary information for phylogeny and population genetics on Chinese Primula species.

A platinum-ruthenium hybrid prodrug with multi-enzymatic activities for chemo-catalytic therapy of hypoxic tumors

Regulation of tumor hypoxia and redox homeostasis is a promising strategy for cancer therapy. Nanocatalytic medicine has played more and more important roles in this field because it can cleverly convert the efficiency and selectivity of catalysis into high therapeutic efficiency. Herein, we developed a platinum(iv)-ruthenium hybrid prodrug, named as Pt-Ru, for efficient chemo-catalytic synergistic therapy of hypoxic tumors. The ruthenium hybridization endowed the Pt(iv) prodrug with multi-enzyme catalytic activity, that is, mimicking catalase (CAT) to generate O2 in situ, mimicking peroxidase (POD) to produce reactive oxygen species, and mimicking glutathione peroxidase (GPx) to deplete GSH, thus effectively overcoming tumor hypoxia and cisplatin resistance. As a result, Pt-Ru treatment led to a superior anticancer efficacy to cisplatin both in vitro and in vivo. This work suggested redox homeostasis regulation as a tantalizing angle for developing the next generation of platinum drugs.

[Detection and analysis of intestinal flora diversity in patients with complex anal fistula]

Objective: To explore the possibility that the intestinal flora profile in complex anal fistula patients is different to that of healthy controls. This was assessed by sequencing of 16S rDNA in fecal samples from cohorts representing these populations. Methods: Fecal samples were collected from 30 complex anal fistula patients and 30 matched healthy controls. Patients were included if they met the diagnostic criteria of cryptoglandular anal fistula and had exhibited symptoms for more than 3 months. Complex anal fistula is diagnosed under the following circumstances: if the fistula in question spans 2/3 or more of the diameter of the anal sphincter; if there are more than two external orifices or fistula tracks; or if recurrence is observed after previous anal fistula surgery. Patients were excluded if there were comorbities including inflammatory bowel disease (as assessed by colonoscopy), chronic diarrhea, chronic constipation, diabetes, gastrointestinal malignancies, liver/ kidney dysfunction, or cognitive impairment. Patients whose anal fistulas were caused by Crohn's disease, trauma, special infections (such as actinomycosis and tuberculosis) were also excluded, as were those who had used antibiotics, prebiotics, or probiotics that may affect intestinal microecology in the month prior to the study. Total bacterial genomic DNA was extracted by PCR amplification of the V4 hypervariable region of the 16S rRNA sequences. High-throughput sequencing and data analysis were performed on the Illumina Miseq platform. Finally, operational taxonomic unit (OTU) clustering, alpha diversity and LEfSE data analysis were carried out. The larger the Chao or ACE index is, the higher the species abundance of the microflora is expected to be. Similarly, a smaller value for the Simpson index or a larger value for the Shannon index indicates greater microflora diversity. There was no statistically significant difference in gender, age, body mass index (BMI), drinking history, or smoking history between the two groups (P>0.05), indicating that they were comparable. Results: The α-diversity analysis including ACE, Chao, Shannon and Simpson indexes indicated a richer diversity of intestinal microflora in complex anal fistula patients than in healthy controls. In both patients and controls, OUT cluster analysis demonstrated that 93.4%±32.0% and 87.4%±41.2% of sequences were from Firmicutes and Bacteroidetes spp., respectively. On a genus level, samples from anal fistula patients showed a greater abundance of Prevotella spp. (4.9%±7.4% vs. 0.1%±1.1%, P<0.001), Megamonas (3.9%±8.2% vs. 0.5%±4.2%, P<0.05) and Lachnospira (2.6%±5.7% vs. 0.1%±3.4%, P<0.05), while showing a lesser abundance of Proteobacteria spp. (0.02%±4.2% vs. 9.3%±14.4%, P<0.01), Enterococcus (0.02%±2.3% vs. 9.3%±19.6%, P<0.05), Bacteroides (24.7%±9.9% vs. 29.8%±9.1%, P<0.05) and Klebsiella (0.4%±4.2% vs. 3.9%±7.3%, P<0.05) compared with healthy controls. Intestinal flora diversity in the complex anal fistula group was richer than in controls, as indicated by a higher ACE index (293.30±44.00 vs. 218.75±33.83, t=102.069, P<0.001), a higher Chao index (318.40±41.99 vs. 250.00±46.38, t=77.818, P=0.028), a higher Shannon index (3.36±0.29 vs. 2.43±0.34, t=9.657, P=0.001), and a lower Simpson index (0.103±0.013 vs. 0.131±0.013, t=5.551, P=0.046). LDA effect size analysis suggests that the main strains of Veillonellaceae, Selenemondales and Negativicutes, which all belong to the phylum Firmicutes, have the greatest influence on the above difference (LDA>4). Conclusions: The diversity of intestinal flora in patients with complex anal fistula is greater than in healthy controls, suggesting that these bacteria or their metabolites may be involved in the occurrence and development of anal fistulas.

[Expression and functional SNP loci screen of ATM from coal worker's pneumoconiosis]

Objective: To detect of gene expression and genotype of the ataxia telangiectasia mutated (ATM) from coal workers' pneumoconiosis (CWP) , It is explored whether CWP is related to ATM gene. Methods: In October 2020, the relevant information of 264 subjects who received physical examination or medical treatment in the Department of occupational diseases of Guiyang public health treatment center from January 2019 to September 2020 was collected. Through the occupational health examination, 67 healthy people with no history of exposure to occupational hazards were selected as the healthy control group; The coal miners with more than 10 years of coal dust exposure history and small shadow in the lung but not up to the diagnostic criteria were the dust exposure control group, a total of 66 people; The patients with the same history of coal dust exposure and confirmed stage I were coal worker's pneumoconiosis stage I group, a total of 131 people. The expression of ATM was detected by QRT PCR. ATM rs189037 and rs1801516 were genotyped by massarray. Results: There was significant difference in the expression of ATM among the groups (P<0.05) ; Compared with the healthy control group, the expression of ATM in the dust exposed control group was significantly increased (P<0.05) . With the occurrence and development of CWP, the GG of rs189037 wild type decreased, the GA of mutant heterozygote and AA of homozygote increased, but the difference was not statistically significant (P>0.05) ; Rs1801516 wild type GG and mutant heterozygote GA had no significant changes (P>0.05) . There were significant differences in age, neutrophils and basophils among rs189037 groups (all P<0.05) . There were no significant differences in blood pressure, eosinophils, lymphocytes, monocytes, smoking and drinking history among rs189037 groups (all P>0.05) . Compared with wild-type GG, the or of mutant heterozygotes and homozygotes increased, but the differences were not statistically significant (P>0.05) . Conclusion: ATM gene may be one of the early activation genes of CWP and rs189037 may be the functional loci which affects gene expression. ATM gene is related to inflammatory response, Neutrophils and basophils have an impact on the development of CWP.

Toxicity of CuS/CdS semiconductor nanocomposites to liver cells and mice liver

Semiconductor nanomaterials not only bring great convenience to peoples lives but also become a potential hazard to human health. The purpose of this study was to evaluate the toxicity of CuS/CdS nanocomposites in hepatocytes and mice liver. The CuS/CdS semiconductor nanocomposites were synthesized by a biomimetic synthesis - ion exchange strategy. Nanosize was confirmed by high-resolution transmission electron microscopy and dynamic light scattering. The composition and physical properties were measured by powder X-ray diffraction, Fourier transform infrared spectra, atomic absorption spectroscopy, thermogravimetry-differential scanning calorimetry and zeta potential analysis. The results revealed that CuS/CdS nanocomposites had 8.7 nm diameter and negative potential. Ion exchange time could adjust the ratio of CuS and CdS in nanocomposites. The toxicological study revealed that CuS/CdS nanocomposites could be internalized into liver cells, inhibited endogenous defense system (e.g. GSH and SOD), induced the accumulation of oxidation products (e.g. ROS, GSSG and MDA), and caused hepatocyte apoptosis. The in vivo experiments in Balb/c mice showed that the experimental dose (4 mg/kg) didn't cause observable changes in mice behavior, physical activity and pathological characteristics, but the continuous accumulation of Cd²⁺ in the liver and kidney might be responsible for its long-term toxicity.

Regulating Tumor N6 -Methyladenosine Methylation Landscape using Hypoxia-Modulating OsSx Nanoparticles

The epigenetic dysregulation and hypoxia are two important factors that drive tumor malignancy, and N⁶ -methyladenosine (m⁶ A) in mRNA is involved in the regulation of gene expression. Herein, a nanocatalyst OsS_x -PEG (PEG = poly(ethylene glycol)) nanoparticles (NPs) as O₂ modulator is developed to improve tumor hypoxia. OsS_x -PEG NPs can significantly downregulate genes involved in hypoxia pathway. Interestingly, OsS_x -PEG NPs elevate RNA m⁶ A methylation levels to cause the m⁶ A-dependent mRNA degradation of the hypoxia-related genes. Moreover, OsS_x -PEG NPs can regulate the expression of RNA m⁶ A methyltransferases and demethylases. Finally, DOX@OsS_x -PEG (DOX = doxorubicin; utilized as a model drug) NPs modulate tumor hypoxia and regulate mRNA m⁶ A methylation of hypoxia-related genes in vivo. As the first report about relationship between catalytic nanomaterials and RNA modifications, the research opens a new avenue for unveiling the underlying action mechanisms of hypoxia-modulating nanomaterials and shows potential of regulating RNA modification to overcome chemoresistance.

Precisely Assembled Nanoparticles against Cisplatin Resistance via Cancer-Specific Targeting of Mitochondria and Imaging-Guided Chemo-Photothermal Therapy

Cisplatin resistance in tumor cells is known mainly due to the reduced accumulation of platinum ions by efflux, detoxification by intracellular GSH, and nucleotide excision repair machinery-mediated nuclear DNA repair. In this work, theranostic Pt(IV)-NPs, which are precisely self-assembled by biotin-labeled Pt(IV) prodrug derivative and cyclodextrin-functionalized IR780 in a 1:1 molecular ratio, have been developed for addressing all these hurdles via mitochondria-targeted chemotherapy solely or chemophotothermal therapy. In these nanoparticles, IR780 as a small-molecule dye acts as a mitochondria-targeting ligand to make Pt(IV)-NPs relocate finally in the mitochondria and release cisplatin. As demonstrated by in vitro and in vivo experiments, Pt(IV)-NPs can markedly facilitate cancer-specific mitochondrial targeting, inducing mitochondrial dysfunction and mitochondrial DNA (mtDNA) damage, thus greatly increasing the Pt accumulation, reducing the GSH levels, and avoiding DNA repair machinery in cisplatin-resistant cancer cells (A549R), finally resulting in significant inhibition of A549R tumor growth on animal models by chemotherapy solely. Upon near-infrared irradiation, mitochondria-targeted chemophotothermal synergistic therapy can be realized, further overcoming cisplatin resistance and even eliminating A549R tumors completely. Moreover, such novel Pt(IV)-NPs integrate multimodal targeting (cancer and mitochondria targeting), imaging (near-infrared imaging and photoacoustic imaging), and therapeutic (chemo- and photothermal therapy) moieties in a constant ratio (1:1:1) into a single, reproducible, and structurally homogeneous entity, avoiding nonuniform drug loading and premature leakage as well as the discrete steps of imaging and therapy, which thus is more beneficial for precise therapeutics and future clinical translation.

CAIXplatins: Highly Potent Platinum(IV) Prodrugs Selective Against Carbonic Anhydrase IX for the Treatment of Hypoxic Tumors

Hypoxia and the acidic microenvironment play a vital role in tumor metastasis and angiogenesis, generally compromising the chemotherapeutic efficacy. This provides a tantalizing angle for the design of platinum(IV) prodrugs for the effective and selective killing of solid tumors. Herein, two carbonic anhydrase IX (CAIX)-targeting platinum(IV) prodrugs have been developed, named as CAIXplatins. Based on their strong affinity for and inhibition of CAIX, CAIXplatins can not only overcome hypoxia and the acidic microenvironment, but also inhibit metabolic pathways of hypoxic cancer cells, resulting in a significantly enhanced therapeutic effect on hypoxic MDA-MB-231 tumors both in vitro and in vivo compared with cisplatin/oxaliplatin, accompanied with excellent anti-metastasis and anti-angiogenesis activities. Furthermore, the cancer selectivity indexes of CAIXplatins are 70-90 times higher than those of cisplatin/oxaliplatin with effectively alleviated side-effects.

A halogen ion-selective phosphorescence turn-on probe based on induction of Pt–Pt interactions

A halogen ion induced self-assembly of square-planar platinum complexes has been, for the first time, observed and applied as a turn-on phosphorescent probe for Cl⁻.

Traceable in-cell synthesis and cytoplasm-to-nucleus translocation of a zinc Schiff base complex as a simple and economical anticancer strategy

A facile and cheap strategy based on visualized in-cell synthesis of theranostic Zn Schiff base complexes realizes cancer-specific therapy.

Folate receptor-targeted theranostic IrSx nanoparticles for multimodal imaging-guided combined chemo-photothermal therapy

Nano-drug delivery systems with multi-modality imaging capacities are worth pursuing because they integrate diagnostic and therapeutic functions. Herein, we report the design, synthesis and evaluation of modified iridium sulfide (IrS_x) nanoparticles (NPs) for cancer therapy in vitro and in vivo. This nanosystem was prepared by modifying IrS_x with polyethylene glycol (PEG) conjugated to the targeting ligand folate (FA) for multimodal imaging-guided combined chemo-photothermal therapy. Upon PEG modification, the small IrS_x NPs (about 4 nm) self-assembled into much larger (about 120 nm) IrS_x-PEG-FA NPs, which exhibited high photostability, ideal photothermal effect, high drug loading and pH-/photothermal-responsive drug release properties. By using the model anticancer drug camptothecin (CPT), we demonstrated that CPT@IrS_x-PEG-FA can effectively target FA-receptor-positive cancer cells in vitro and show efficient tumor accumulation in vivo. The combination of CPT@IrS_x-PEG-FA treatment and irradiation with an 808 nm laser resulted in complete tumor elimination. Moreover, photothermal/photoacoustic (PA)/computed tomography (CT) imaging provided an effective means to monitor the therapeutic effects. Interestingly, the nanoparticles can be cleared, resulting in low systematic toxicity of CPT@IrS_x-PEG-FA. Our work demonstrates that the as-prepared IrS_x-PEG-FA NPs present a promising platform for the construction of multifunctional theranostic agents for cancer therapy.

Cancer-specific chemotherapeutic strategy based on the vitamin K3 mediated ROS regenerative feedback and visualized drug release in vivo

A promising theranostic nanosystem VK3-CPT@Ru-CD is designed and fabricated by the host-guest driven self-assembly between the fluorescent adamantine-functionalized Ru(II) complexes and the ROS-labile-cyclodextrin modified thioketal linkers, in which anticancer drug camptothecin (CPT) and vitamin K3 (VK3) are effectively co-encapsulated. On account of the generative feedback between the intracellular redox cycling of VK3 and the high degree of ROS-triggered collapse of nanoparticles, VK3-CPT@Ru-CD can facilitate cancer-specific ROS amplification and drug release selectively in cancer cells, thus realizing the selective killing of tumor with minimal side-effects both in vitro and in vivo, the therapeutic effect of which is more prominent than the free anti-cancer drugs. More interestingly, the menadione structure of encapsulated VK3 can effectively quench the inherent fluorescence of Ru-CD, and a fluorescence lightening up phenomenon is observed accompanied with the ROS-triggered drug release, which can be utilized for real-time tracking of drug release in vitro and in vivo.

Three-in-One Self-Assembled Nanocarrier for Dual-Drug Delivery, Two-Photon Imaging, and Chemo-Photodynamic Synergistic Therapy

We herein present a three-in-one nanoplatform (named Fu/LD@RuCD) for dual-drug delivery, two-photon imaging, and chemo-photodynamic synergistic therapy, enabled by simple self-assembly between adamantine-functionalized ruthenium complexes ([Ru(phen-ad)₃](PF₆)₂, Ru) and natural cyclodextrin (β-CD) monomers. By host-guest chemistry, nanocarrier RuCD 70-90 nm in diameter is fabricated through a very simple mixing step in water at room temperature, in which the octahedral configuration of Ru complex provides a rigid skeleton and the hydrogen bonding of secondary hydroxyl groups formed between two adjacent β-CD monomers displays a bridging role allowing for three-dimensional architectures. The dual-drug-loaded nanoparticle Fu/LD@RuCD (Fu: 5-fluorouracil; LD: lonidamine) effectively penetrates into cancer cells in 8 h and selectively accumulates in lysosomes, in which dual-drug release is promoted by the mildly acidic environment. Under visible light irradiation, nanocarrier RuCD exhibits excellent photodynamic therapy capability by producing sufficient reactive oxygen species and damaging lysosomes, accordingly 5-fluorouracil and lonidamine can escape from lysosomes and reach their sites of action, resulting in mitochondria dysfunction and cancer cell apoptosis. Simultaneously, the excellent photophysical properties of the nanocarrier enable the facile track of drug delivery under one-photon and two-photon excitation. Moreover, in vivo anticancer investigations show that Fu/LD@RuCD can effectively inhibit the tumor growth without systemic side effects by chemo-photodynamic synergistic therapy, and the therapeutic effect is better than the free anticancer drugs and the sole therapeutic modality.

Correction: A self-assessed photosensitizer: inducing and dual-modal phosphorescence imaging of mitochondria oxidative stress

Correction for ‘A self-assessed photosensitizer: inducing and dual-modal phosphorescence imaging of mitochondria oxidative stress’ by Jing Yang et al., Chem. Commun., 2018, DOI: 10.1039/c7cc07797a.

A self-assessed photosensitizer: inducing and dual-modal phosphorescence imaging of mitochondria oxidative stress

Mitochondria-targeted Ir(iii)–nitroxide conjugates act as self-assessed PDT agents by simultaneously inducing and dual-modal phosphorescence imaging of mitochondrial oxidative stress.

Linker length affects expression and bioactivity of the onconase fusion protein in Pichia pastoris

The aim of this study was to analyze the effect of linker length on the expression and biological activity of recombinant protein onconase (ONC) in fusion with human serum albumin (HSA) in Pichia pastoris. Four flexible linkers with different lengths namely Linker L0, L1: (GGGGS)1, L2: (GGGGS)2, and L3:(GGGGS)3 were inserted into the fusion gene and referred to as HSA-n-ONC, where N = 0, 5, 10, or 15. The sequence of the fusion gene HSA-ONC was designed based on the GC content and codon bias in P. pastoris; the signal peptide of albumin was used as the secretion signal. Gene sequences coding for the fusion protein with different linkers were inserted into pPICZα-A to form recombinant plasmids pPICZα-A/HSA-n-ONC, which were then transformed into P. pastoris X-33 for protein expression. Ideal conditions for expression of the fusion proteins were optimized at a small scale, using shake flasks before proceeding to mass production in 10-L fermenters. The recombinant fusion proteins were purified by aqueous two-phase extraction coupled with DEAE anion exchange chromatography, and their cytotoxic effect on the tumor cell was evaluated by the sulforhodamine B assay. The results showed that the expressed amount of fusion proteins had no significant relationship with the length of different linkers and rHSA-0-ONC had no cytotoxic effect on the tumor cells. While rHSA-5-ONC and rHSA-10-ONC had a weak cytotoxic effect, rHSA-15-ONC could kill various tumor cells in vitro. In summary, the biological activity of the fusion protein gradually improved with increasing length of the linker.

Volume reflection holographic confocal imaging

The Denisyuk volume reflection hologram is produced with spatially incoherent light to form an image-plane hologram. The image formed in readout combines the properties of volume holography and confocal image formation.

Hepatitis B virions isolated with antibodies to the pre-S1 domain reveal occult viremia by PCR in Alaska Native HBV carriers who have seroconverted

BACKGROUND

Occult viremia occurring before the appearance of HBsAg or after the disappearance of HBsAg is detectable by gene amplification technologies whose efficiency depends on nucleic acid preparation.

STUDY DESIGN AND METHODS

To isolate HBV DNA from viremic plasma, immunoaffinity capture (IAC) of intact HBV with biotinylated pre-S1 antibodies coupled to streptavidin-coated magnetic beads was evaluated. IAC was compared with a silica-gel method (Qiagen [QSG]) and its two modifications wherein the samples were heated with lysis buffer at 60(o)C for 10 minutes (QSG-60) or at 58 degrees C for 60 minutes with proteinase-K (QSG-PK). Each HBV DNA sample was tested by heminested PCR amplification of the HBV gene sequences. A total of 36 coded serum samples were tested, including three HBsAg-positive controls and 33 former chronic HBV carriers who had seroconverted (developed antibody to HBsAg [anti-HBs]). Commercially available seroconversion panels (PHM 907, 911, and 922) were similarly tested for window-period viremia.

RESULTS

In the 33 former chronic HBV carriers who had seroconverted, IAC revealed HBV DNA in 17 samples, whereas it was revealed in only 11 samples by QSG-PK (p = 0.031), 10 by QSG-60 (p = 0.016), and 9 by QSG (p = 0.0078). However, HBV DNA was not amplified from the 17 samples at 1-in-10 dilutions; thus, they were considered to have low-level viremia. IAC revealed HBV DNA as early as or earlier than the other methods in PHM 907, 911, and 922 panels.

CONCLUSION

IAC is apparently an optimal method of sample preparation for amplification of HBV DNA in patients in the pre-HBsAg window period, and for detecting low-level viremia persistent in several individuals who were former chronic HBV carriers who had seroconverted (developed anti-HBs).

Properties of cyanovirin-N (CV-N): inactivation of HIV-1 by sessile cyanovirin-N (sCV-N)

Cyanovirin-N (CV-N) is a novel anti-HIV protein isolated and characterized from a cyanobacterium Nostoc ellipsosporum. CV-N protein is a single 101 amino acid chain containing two intrachain disulphide bonds and considerable internal sequence duplication, but no significant homology to previously described proteins or to the transcription products of known nucleotide sequences. In solution, CV-N exists largely as a beta-sheet protein with internal two-fold pseudosymmetry. CV-N irreversibly inactivates diverse laboratory strains, primary isolates and clades of HIV-1, as well as strains of HIV-2 and simian immunodeficiency virus (SIV). CV-N binds with extremely high affinity to highly conserved binding site(s) on the viral envelope glycoprotein gp120, preventing virus-to-cell fusion, viral entry and infection of cells. The CV-N binding site appears to overlap, but is not identical with, the unique carbohydrate-dependent epitope 2G12, and may lie predominantly within an immunologically "silent" region of gp120. CV-N is undergoing preclinical development for topical anti-HIV prophylactic (e.g., microbicidal) applications to prevent sexual transmission of HIV. Since CV-N may be immunogenic in humans, methods for using CV-N for ex vivo inactivation of HIV in blood, plasma, or putative vaccines preferably would allow for its exclusion from biologicals for parenteral use. To explore this concept we biotinylated CV-N (bCV-N) and coupled it to streptavidin coated magnetic beads to provide a product which we termed sessile CV-N (sCV-N). When reacted with a laboratory strain and a primary isolate of HIV- 1, the sCV-N completely inactivated 100 TCID50 of the virus. However RT-PCR of the viral extracts indicated that only a fraction of the virus was removed by the sCV-N, leaving behind a relatively larger fraction of non-infectious virus in the supernatant which we designated as replication incompetent virions (RIV). It would be worthwhile investigating the role of RIV as a putative HIV vaccine.

Hemodynamic effects of brief pulmonary hemostasis

We determined the hemodynamic effects of brief hemostasis in isolated blood-perfused rat lungs held at constant inflation pressure. Three periods of hemostasis, each lasting 20 min, alternated with equal durations of perfusion. Pulmonary vascular resistance (PVR), calculated as the ratio of the pulmonary arterial- (Ppa) left atrial (Pla) pressure difference to flow, was determined at baseline and after the third hemostasis period. Hemostasis increased PVR by 127% above baseline at constant Ppa and Pla (n = 8; P < 0.05) and by 71% at constant Pla and constant flow (n = 16; P < 0.05). The PVR increases were significantly attenuated by platelet (n = 5) or red blood cell (n = 4) removal from the lung perfusion, mechanical ventilation (n = 5), indomethacin (2 X 10(-6) M; n = 5), papaverine (10(-5) M; n = 4), and the thromboxane blocker SQ-29548 (7.8 X 10(-5) M; n = 4). By micropuncture we determined that the posthemostasis increase of the total pressure drop was 66% due to an increase of the venous pressure drop (P < 0.05). Isogravimetric pressure and lung water were not significantly altered by hemostasis. We conclude that brief hemostasis in the rat lung induces platelet- and red blood cell-dependent increase of vascular resistance. This effect may be attributable to hemostasis-induced platelet activation leading to thromboxane release.

Sonographic patterns of ribs with tumor involvement

We analyzed the sonographic appearance of the ribs when there was tumor involvement in 16 patients (12 men and 4 women). The tumors included 11 carcinomas, 3 nonepithelial malignancies and 2 benign tumors. Three sonographic patterns on the cross section of abnormal ribs were identified. Pattern I was an eccentrical hyperechoic plate-like shadow inside a hypoechoic tumor. Pattern II was a round hyperechoic shadow or ring in the center of a hypoechoic tumor. Pattern III was a hypoechoic tumor only. The Pancoast tumor manifested pattern I. Metastatic cancer, mostly squamous cell carcinoma, manifested pattern II, and both malignant and benign tumors could manifest pattern III. In sonography, the margin and shape of the tumors, the change in the acoustic shadow of the rib and the pleural line did not differentiate the malignant tumors from benign tumors. When we routinely took a biopsy of these tumors under sonar guidance, the diagnostic yield was 100% without any complications. We conclude that the rib should be evaluated in chest sonography, and that pattern recognition and biopsy under sonar guidance are most useful.

Design of a general optical interconnection system with phase-only masks

A general optical interconnection system with phase-only masks is proposed; it is a high-efficiency system. The optical general transform theory is modified for the design. Results show that an arbitrary one-to-one interconnection pattern between an array of N sources and N detectors can be achieved by two phase-only masks in which the number of sampling points is N(2).