Platelet membrane-camouflaged silver metal-organic framework drug system against infections caused by methicillin-resistant Staphylococcus aureus.

BACKGROUND: Due to the intelligent survival strategy and self-preservation of methicillin-resistant Staphylococcus aureus (MRSA), many antibiotics are ineffective in treating MRSA infections. Nano-drug delivery systems have emerged as a new method to overcome this barrier. The aim of this study was to construct a novel nano-drug delivery system for the treatment of MRSA infection, and to evaluate the therapeutic effect and biotoxicity of this system. We prepared a nano silver metal-organic framework using 2-methylimidazole as ligand and silver nitrate as ion provider. Vancomycin (Vanc) was loaded with Ag-MOF, and nano-sized platelet vesicles were prepared to encapsulate Ag-MOF-Vanc, thus forming the novel platelet membrane-camouflaged nanoparticles PLT@Ag-MOF-Vanc. RESULTS: The synthesized Ag-MOF particles had uniform size and shape of radiating corona. The mean nanoparticle size and zeta potential of PLT@Ag-MOF-Vanc were 148 nm and - 25.6 mV, respectively. The encapsulation efficiency (EE) and loading efficiency (LE) of vancomycin were 81.0 and 64.7 %, respectively. PLT@Ag-MOF-Vanc was shown to be a pH-responsive nano-drug delivery system with good biocompatibility. Ag-MOF had a good inhibitory effect on the growth of three common clinical strains (Escherichia coli, Pseudomonas aeruginosa, and S. aureus). PLT@Ag-MOF-Vanc showed better antibacterial activity against common clinical strains in vitro than free vancomycin. PLT@Ag-MOF-Vanc killed MRSA through multiple approaches, including interfering with the metabolism of bacteria, catalyzing reactive oxygen species production, destroying the integrity of cell membrane, and inhibiting biofilm formation. Due to the encapsulation of the platelet membrane, PLT@Ag-MOF-Vanc can bind to the surface of the MRSA bacteria and the sites of MRSA infection. PLT@Ag-MOF-Vanc had a good anti-infective effect in mouse MRSA pneumonia model, which was significantly superior to free vancomycin, and has no obvious toxicity. CONCLUSIONS: PLT@Ag-MOF-Vanc is a novel effective targeted drug delivery system, which is expected to be used safely in anti-infective therapy of MRSA.

Characterization of an Ecdysteroid-Regulated 16 kDa Protein Gene in Chinese Oak Silkworm, Antheraea pernyi (Lepidoptera: Saturniidae).

A large number of ecdysteroid-regulated 16 kDa proteins (ESR16s) of insects have been isolated and annotated in GenBank; however, knowledge on insect ESR16s remain limited. In the present study, we characterized an ecdysteroid-regulated 16 kDa protein gene isolated in Chinese oak silkworm, Antheraea pernyi Guérin-Méneville ('ApESR16' in the following), an important silk-producing and edible insect. The obtained cDNA sequence of ApESR16 is 1,049 bp, harboring an open reading frame of 441 bp that encodes a polypeptide of 146 amino acids. CD-search revealed that ApESR16 contains the putative cholesterol/lipid binding sites on conserved domain Npc2_like (Niemann-Pick type C-2) belonging to the MD-2-related lipid-recognition superfamily. Sequence comparison revealed that ApESR16 exhibits 51-57% identity to ESR16s of lepidopteran insects, 36-41% identity to ESR16 or NPC2a of nonlepidopteran insects, and 28-32% identity to NPC2a of vertebrates, indicating a high sequence divergence during the evolution of animals. Phylogenetic analysis found that the used sequences were divided into two groups corresponding to vertebrates and invertebrates, and the used insect sequences were also well clustered according to their families. The A. pernyi ESR16 mRNA is expressed during all four developmental stages and in all tested tissues. Injection of 20-hydroxyecdysone (20-E) into A. pernyi diapausing pupae triggering diapause termination induced upregulation of ESR16 mRNA compared to the diapausing pupae, with the highest expression level at day 2 in the ovaries but day 12 in the fat body. Our results suggested that ApESR16 might be a diapause-related gene and plays a vital role in the pupal diapause of A. pernyi.

Novel calibration algorithm for a three-axis strapdown magnetometer.

A complete error calibration model with 12 independent parameters is established by analyzing the three-axis magnetometer error mechanism. The said model conforms to an ellipsoid restriction, the parameters of the ellipsoid equation are estimated, and the ellipsoid coefficient matrix is derived. However, the calibration matrix cannot be determined completely, as there are fewer ellipsoid parameters than calibration model parameters. Mathematically, the calibration matrix derived from the ellipsoid coefficient matrix by a different matrix decomposition method is not unique, and there exists an unknown rotation matrix R between them. This paper puts forward a constant intersection angle method (angles between the geomagnetic field and gravitational field are fixed) to estimate R. The Tikhonov method is adopted to solve the problem that rounding errors or other errors may seriously affect the calculation results of R when the condition number of the matrix is very large. The geomagnetic field vector and heading error are further corrected by R. The constant intersection angle method is convenient and practical, as it is free from any additional calibration procedure or coordinate transformation. In addition, the simulation experiment indicates that the heading error declines from ±1° calibrated by classical ellipsoid fitting to ±0.2° calibrated by a constant intersection angle method, and the signal-to-noise ratio is 50 dB. The actual experiment exhibits that the heading error is further corrected from ±0.8° calibrated by the classical ellipsoid fitting to ±0.3° calibrated by a constant intersection angle method.

Inundative practice for screening siRNA management candidates against a notorious predatory beetle using olfactory silencing.

Calosoma maximoviczi, a predatory pest beetle, poses a significant threat to wild silk farm production due to its predation on wild silkworms. Given the coexistence of this species with beneficial silkworms in the farm orchards, chemical pesticides are not an ideal solution for controlling its population. In this study, we employed a comprehensive multi-target RNA interference (RNAi) approach to disrupt the olfactory perception of C. maximoviczi through independently silencing 16 odorant receptors (ORs) in the respective genders. Specifically, gene-specific siRNAs were designed to target a panel of ORs, allowing us to investigate the specific interactions between odorant receptors and ligands within this species. Our investigation led to identifying four candidate siOR groups that effectively disrupted the beetle's olfactory tracking of various odorant ligands associated with different trophic levels. Furthermore, we observed sex-specific differences in innate RNAi responses reflected by subsequent gene expression, physiological and behavioral consequences, underscoring the complexity of olfactory signaling and emphasizing the significance of considering species/sex-specific traits when implementing pest control measures. These findings advance our understanding of olfactory coding patterns in C. maximoviczi beetles and establish a foundation for future research in the field of pest management strategies.

Restoration of metal homeostasis: a potential strategy against neurodegenerative diseases.

Metal homeostasis is critical to normal neurophysiological activity. Metal ions are involved in the development, metabolism, redox and neurotransmitter transmission of the central nervous system (CNS). Thus, disturbance of homeostasis (such as metal deficiency or excess) can result in serious consequences, including neurooxidative stress, excitotoxicity, neuroinflammation, and nerve cell death. The uptake, transport and metabolism of metal ions are highly regulated by ion channels. There is growing evidence that metal ion disorders and/or the dysfunction of ion channels contribute to the progression of neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), and multiple sclerosis (MS). Therefore, metal homeostasis-related signaling pathways are emerging as promising therapeutic targets for diverse neurological diseases. This review summarizes recent advances in the studies regarding the physiological and pathophysiological functions of metal ions and their channels, as well as their role in neurodegenerative diseases. In addition, currently available metal ion modulators and in vivo quantitative metal ion imaging methods are also discussed. Current work provides certain recommendations based on literatures and in-depth reflections to improve neurodegenerative diseases. Future studies should turn to crosstalk and interactions between different metal ions and their channels. Concomitant pharmacological interventions for two or more metal signaling pathways may offer clinical advantages in treating the neurodegenerative diseases.

Behavioural regulator and molecular reception of a double-edge-sword hunter beetle.

BACKGROUND: The black carabid beetle Calosoma maximoviczi is a successful predator that serves as both a beneficial insect and a severe threat to economic herbivores. Its hunting technique relies heavily on olfaction, but the underlying mechanism has not been studied. Here, we report the electrophysiological, ecological and molecular traits of bioactive components identified from a comprehensive panel of natural odorants in the beetle-prey-plant system. The aim of this work was to investigate olfactory perceptions and their influence on the behaviours of C. maximoviczi. RESULTS: Among the 200 identified volatiles, 18 were concentrated in beetle and prey samples, and 14 were concentrated in plants. Insect feeding damage to plants led to a shift in the emission fingerprint. Twelve volatiles were selected using successive electrophysiological tests. Field trials showed that significant sex differences existed when trapping with a single chemical or chemical mixture. Expression profiles indicated that sex-biased catches were related to the expression of 15 annotated CmaxOBPs and 40 CmaxORs across 12 chemosensory organs. In silico evaluations were conducted with 16 CmaxORs using modelling and docking. Better recognition was predicted for the pairs CmaxOR5-(Z)-3-hexenyl acetate, CmaxOR6-ß-caryophyllene, CmaxOR18-(E)-ß-ocimene and CmaxOR18-tetradecane, with higher binding affinity and a suitable binding pocket. Lastly, 168Y in CmaxOR6 and 142Y in CmaxOR18 were predicted as key amino acid residues for binding ß-caryophyllene and tetradecane, respectively. CONCLUSION: This work provides an example pipeline for de novo investigation in C. maximoviczi baits and the underlying olfactory perceptions. The results will benefit the future development of trapping-based integrated pest management strategies and the deorphanization of odorant receptors in ground beetles. © 2022 Society of Chemical Industry.

The complete mitochondrial genome of antheraea pernyi strain qing_6 (lepidoptera: Saturniidae).

Here, we report the complete mitochondrial (mt) genome of Antheraea pernyi Qing_6, an improved strain serving silk production and edible insect resource for 50 years in Northeast China. The circular mt genome spans 15,572 bp in length and contains 37 typical coding genes (13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes). Its A + T-rich region is 552 bp in size exhibiting identical sequence with the first modern improved strain Qinghuang_1. Comparison analysis identified only 12 variable sites (5 substitutions and 7 indels) between Qing_6 and Qinghuang_1. The phylogenetic analysis also clustered Qing_6 and Qinghuang_1 together first, which was in line with the breeding history of the two strains.

Prognostic and clinicopathological value of melanoma-associated antigen D4 in patients with glioma.

The aim of the present study was to evaluate the clinical importance of melanoma-associated antigen D4 (MAGE-D4) expression in glioma, and to identify it as a valuable prognostic biomarker and therapeutic target. To achieve this, the expression of MAGE-D4 protein in 124 tumor tissues from patients with glioma was measured using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC), and the associations between MAGE-D4expression and clinicopathological factors were evaluated. The survival analysis demonstrated the significant prognostic value of MAGE-D4 in glioma using follow-up data. RT-qPCR and IHC analysis confirmed that MAGE-D4 mRNA and protein expression levels were significantly increased in glioma tissues compared with those in normal brain tissues. The present study demonstrated that the percentage of glioma tissues with high expression of MAGE-D4 mRNA was 67.74%, and the percentage positive for MAGE-D4 protein expression was 78.23%. All patients with high MAGE-D4 expression in cancerous tissues experienced significantly reduced median overall survival (OS; 18.00 vs. 33.29 months; P<0.001) and recurrence-free survival (RFS; 12.7 vs. 28.3 months; P<0.001) times compared with those with low MAGE-D4 expression. In the patients with lower grade glioma [World Health Organization (WHO), I-II], similar results were obtained for the OS (26.11 vs. 57.85 months; P=0.013) and RFS (22.7 vs. 55.3 months; P=0.010) times; however, in patients with high-grade glioma (WHO, III-IV), there were no significant differences between high and low MAGE-D4 expression levels with regard to OS and RFS times (P>0.05). Multivariate analysis indicated that high MAGE-D4 protein expression was an important independent prognostic factor for patients with glioma (hazard ratio, 2.384; P=0.005), and was significantly associated with higher grade glioma (P<0.001). These results indicated that MAGE-D4 may be a potential biomarker for glioma and an important prognostic factor for patients with new or recurring glioma.

Involvement of X-chromosome Reactivation in Augmenting Cancer Testis Antigens Expression: A Hypothesis.

Cancer testis antigens (CTAs) are attractive targets for tumor immunotherapy because of their tumor-specific expression. Since more than half of confirmed CTAs are located on the X-chromosome, we asked whether there is a link between CTA expression and X-chromosomes. Recent reports have shown that reactivation of the inactive X-chromosome, known as X-chromosome reactivation (XCR), a unique phenomenon that exists in many high-risk tumors in women, can transform the expression of many X-linked genes from monoallelic to biallelic. In this review, we discuss the link between CTA and XCR with the hopes of providing some novel insights into tumor biology.

The natural progression of VGAMs and the need for urgent medical attention: a systematic review and meta-analysis.

BACKGROUND: Vein of Galen aneurysmal malformations (VGAMs) are congenital disorders that may require emergency treatment and some may cause sudden death before medical attention is provided. Some patients also have a spontaneous thrombosis. OBJECTIVE: To understand the natural progression of VGAMs through a systematic literature review. METHODS: We examined PubMed to identify studies published between July 1973 and March 2015. We determined the proportion of patients with VGAM who died before receiving medical attention, who received emergency treatment, or had a spontaneous thrombosis. We pooled estimates of proportions with corresponding 95% CIs calculated using the raw (ie, untransformed) proportions. RESULTS: The 31 studies obtained described the outcome of 754 patients with VGAM. The probability of sudden death risk was 4% (95% CI 1% to 7%; I2=51.6%); of an emergency operation was 46% (95% CI 34% to 58%; I2=93.2%); and of spontaneous thromboses 1% (95% CI 0% to 2%; I2=0%) of cases. Differences between age and clinical outcomes of patients with spontaneous thromboses were significant according to the rank test (Mann-Whitney U test, Z=-2.398, p=0.016), both having a linear correlation (χ2 test, p=0.022). CONCLUSIONS: Over time, the rate of preoperative sudden death in patients with VGAM gradually declined and the rate of emergency operations gradually increased. The outcome of patients with early spontaneous thromboses was good. Our study provides a definitive description of the natural progression of VGAMs and the need for urgent medical attention.

Nonmissile Penetrating Head Injuries: Surgical Management and Review of the Literature.

BACKGROUND: Nonmissile penetrating head injuries (NPHIs) in the civilian population are rare but potentially fatal. Although numerous cases have been reported in the literature, the surgical management of such injuries is still ambiguous, especially with development of surgical techniques. Here, we report 5 cases of NPHIs managed with different surgical techniques and review the literature on surgical treatment of these injuries to outline the appropriate management for these patients from a neurosurgical perspective. METHODS: We retrospectively reviewed 5 cases of NPHIs managed surgically in our department. The clinical data were collected, including cause, type of objects, way of penetration, initial clinical evaluation, imaging, surgical intervention, postoperative care, complication, follow-up, and outcome. In addition, a systematic review of the literature was performed in the PubMed database to search for articles on surgical treatment of these injuries. RESULTS: These 5 cases were caused by twisted steel bar, electric welding rod, and sewing needle, respectively. Preoperative imaging, including computed tomography, magnetic resonance imaging, and digital subtraction angiography, was selectively performed to assist the operative plan. Foreign objects were removed surgically in all cases. Postoperative prophylactic administration of antibiotics and anticonvulsants was used to prevent infectious and epileptic complications. Most of the patients achieved a better outcome except for one. CONCLUSIONS: NPHIs can be fatal but they can be managed with satisfactory results by proper preoperative imaging evaluation, rapid appropriate surgical management, and accurate postoperative care. Personalized surgical intervention should be undertaken depending on the mechanism and extent of the NPHI.

Transcriptome Analysis of the Midgut of the Chinese Oak Silkworm Antheraea pernyi Infected with Antheraea pernyi Nucleopolyhedrovirus.

The Antheraea pernyi nucleopolyhedrovirus (ApNPV) is an exclusive pathogen of A. pernyi. The intense interactions between ApNPV and A. pernyi cause a series of physiological and pathological changes to A. pernyi. However, no detailed report exists regarding the molecular mechanisms underlying the interactions between ApNPV and A. pernyi. In this study, four cDNA libraries of the A. pernyi midgut, including two ApNPV-infected groups and two control groups, were constructed for transcriptomic analysis to provide new clues regarding the molecular mechanisms that underlie these interactions. The transcriptome of the A. pernyi midgut was de novo assembled using the Trinity platform because of the lack of a genome resource for A. pernyi. Compared with the controls, a total of 5,172 differentially expressed genes (DEGs) were identified, including 2,183 up-regulated and 2,989 down-regulated candidates, of which 2,965 and 911 DEGs were classified into different GO categories and KEGG pathways, respectively. The DEGs involved in A. pernyi innate immunity were classified into several categories, including heat-shock proteins, apoptosis-related proteins, serpins, serine proteases and cytochrome P450s. Our results suggested that these genes were related to the immune response of the A. pernyi midgut to ApNPV infection via their essential roles in regulating a variety of physiological processes. Our results may serve as a basis for future research not only on the molecular mechanisms of ApNPV invasion but also on the anti-ApNPV mechanism of A. pernyi.

The complete mitochondrial genome of the Ailanthus silkmoth, Samia cynthia cynthia (Lepidoptera: Saturniidae).

The complete mitochondrial genome (mitogenome) of the Ailanthus silkmoth, Samia cynthia cynthia (Lepidoptera: Saturniidae) was determined. The circular genome is 15,345 bp long, and presents a typical gene organization and order for sequenced mitogenomes of Bombycidea species. The nucleotide composition of the genome is highly A+T biased, accounting for 79.86%. The AT skew of the genome is slightly negative, indicating the occurrence of more Ts than As, as found in other Saturniidae species. All protein-coding genes (PCGs) are initiated by ATN codons, except for COI and COII, which are tentatively designated by CGA and GTG, respectively, as observed in other insects. Four of 13 PCGs, including COI, COII, ATP6, and ND3, harbor the incomplete termination codons, T or TA. With an exception for tRNASer(AGN), all other tRNAs can form a typical clover-leaf structure of mitochondrial tRNA. The 359 bp A+T-rich region of S. c. cynthia contains non-repetitive sequences, but harbors several features common to the Bombycidea insects, including the motif ATAGA followed by a poly-T stretch of 19 bp, a microsatellite-like (AT)7 element preceded by the ATTTA motif, and a poly-A element upstream tRNAMet. The phylogenetic analyses support the morphology-based current hypothesis that Bombycidae and Saturniidae are monophyletic. Our result confirms that Saturniini and Attacini form a reciprocal monophyletic group within Saturniidae.

Comparative genetic diversity and genetic structure of three Chinese silkworm species Bombyx mori L. (Lepidoptera: Bombycidae), Antheraea pernyi Guérin-Meneville and Samia cynthia ricini Donovan (Lepidoptera: Saturniidae).

The genetic diversity and genetic structure of three Chinese silkworm species Bombyx mori L., Antheraea pernyi Guérin-Meneville and Samia cynthia ricini Donovan were comparatively assessed based on RAPD markers. At the species level, A. pernyi and B. mori showed high levels of genetic diversity, whereas S. cynthia ricini showed low level of genetic diversity. However, at the strain level, A. pernyi had relatively highest genetic diversity and B. mori had lowest genetic diversity. Analysis of molecular variance (AMOVA) suggested that 60% and 72% of genetic variation resided within strains in A. pernyi and S. cynthia ricini, respectively, whereas only 16% of genetic variation occurred within strains in B. mori. In UPGMA dendrogram, individuals of A. pernyi and B. mori formed the strain-specific genetic clades, whereas those of S. cynthia ricini were distributed in a mixed way. The implications of these results for the conservation and utilization in breeding programs of three silkworm species are discussed.

Construction of a full-length cDNA Library from Chinese oak silkworm pupa and identification of a KK-42-binding protein gene in relation to pupa-diapause termination.

In this study we successfully constructed a full-length cDNA library from Chinese oak silkworm, Antheraea pernyi, the most well-known wild silkworm used for silk production and insect food. Total RNA was extracted from a single fresh female pupa at the diapause stage. The titer of the library was 5 x 10(5) cfu/ml and the proportion of recombinant clones was approximately 95%. Expressed sequence tag (EST) analysis was used to characterize the library. A total of 175 clustered ESTs consisting of 24 contigs and 151 singlets were generated from 250 effective sequences. Of the 175 unigenes, 97 (55.4%) were known genes but only five from A. pernyi, 37 (21.2%) were known ESTs without function annotation, and 41 (23.4%) were novel ESTs. By EST sequencing, a gene coding KK-42-binding protein in A. pernyi (named as ApKK42-BP; GenBank accession no. FJ744151) was identified and characterized. Protein sequence analysis showed that ApKK42-BP was not a membrane protein but an extracellular protein with a signal peptide at position 1-18, and contained two putative conserved domains, abhydro_lipase and abhydrolase_1, suggesting it may be a member of lipase superfamily. Expression analysis based on number of ESTs showed that ApKK42-BP was an abundant gene in the period of diapause stage, suggesting it may also be involved in pupa-diapause termination.

Comparative genetic diversity and genetic structure of three chinese silkworm species Bombyx mori L. (Lepidoptera: Bombycidae), Antheraea pernyi Guérin-Meneville and Samia cynthia ricini donovan (Lepidoptera: Saturniidae)

The genetic diversity and genetic structure of three Chinese silkworm species Bombyx mori L., Antheraea pernyi Guérin-Meneville and Samia cynthia ricini Donovan were comparatively assessed based on RAPD markers. At the species level, A. pernyi and B. mori showed high levels of genetic diversity, whereas S. cynthia ricini showed low level of genetic diversity. However, at the strain level, A. pernyi had relatively highest genetic diversity and B. mori had lowest genetic diversity. Analysis of molecular variance (AMOVA) suggested that 60 percent and 72 percent of genetic variation resided within strains in A. pernyi and S. cynthia ricini, respectively, whereas only 16 percent of genetic variation occurred within strains in B. mori. In UPGMA dendrogram, individuals of A. pernyi and B. mori formed the strain-specific genetic clades, whereas those of S. cynthia ricini were distributed in a mixed way. The implications of these results for the conservation and utilization in breeding programs of three silkworm species are discussed.