Microglia-targeted inhibition of miR-17 via mannose-coated lipid nanoparticles improves pathology and behavior in a mouse model of Alzheimer's disease.

Neuroinflammation and accumulation of Amyloid Beta (Aß) accompanied by deterioration of special memory are hallmarks of Alzheimer's disease (AD). Effective preventative and treatment options for AD are still needed. Microglia in AD brains are characterized by elevated levels of microRNA-17 (miR-17), which is accompanied by defective autophagy, Aß accumulation, and increased inflammatory cytokine production. However, the effect of targeting miR-17 on AD pathology and memory loss is not clear. To specifically inhibit miR-17 in microglia, we generated mannose-coated lipid nanoparticles (MLNPs) enclosing miR-17 antagomir (Anti-17 MLNPs), which are targeted to mannose receptors readily expressed on microglia. We used a 5XFAD mouse model (AD) that recapitulates many AD-related phenotypes observed in humans. Our results show that Anti-17 MLNPs, delivered to 5XFAD mice by intra-cisterna magna injection, specifically deliver Anti-17 to microglia. Anti-17 MLNPs downregulated miR-17 expression in microglia but not in neurons, astrocytes, and oligodendrocytes. Anti-17 MLNPs attenuated inflammation, improved autophagy, and reduced Aß burdens in the brains. Additionally, Anti-17 MLNPs reduced the deterioration in spatial memory and decreased anxiety-like behavior in 5XFAD mice. Therefore, targeting miR-17 using MLNPs is a viable strategy to prevent several AD pathologies. This selective targeting strategy delivers specific agents to microglia without the adverse off-target effects on other cell types. Additionally, this approach can be used to deliver other molecules to microglia and other immune cells in other organs.

Modification of Lipid-Based Nanoparticles: An Efficient Delivery System for Nucleic Acid-Based Immunotherapy.

Lipid-based nanoparticles (LBNPs) are biocompatible and biodegradable vesicles that are considered to be one of the most efficient drug delivery platforms. Due to the prominent advantages, such as long circulation time, slow drug release, reduced toxicity, high transfection efficiency, and endosomal escape capacity, such synthetic nanoparticles have been widely used for carrying genetic therapeutics, particularly nucleic acids that can be applied in the treatment for various diseases, including congenital diseases, cancers, virus infections, and chronic inflammations. Despite great merits and multiple successful applications, many extracellular and intracellular barriers remain and greatly impair delivery efficacy and therapeutic outcomes. As such, the current state of knowledge and pitfalls regarding the gene delivery and construction of LBNPs will be initially summarized. In order to develop a new generation of LBNPs for improved delivery profiles and therapeutic effects, the modification strategies of LBNPs will be reviewed. On the basis of these developed modifications, the performance of LBNPs as therapeutic nanoplatforms have been greatly improved and extensively applied in immunotherapies, including infectious diseases and cancers. However, the therapeutic applications of LBNPs systems are still limited due to the undesirable endosomal escape, potential aggregation, and the inefficient encapsulation of therapeutics. Herein, we will review and discuss recent advances and remaining challenges in the development of LBNPs for nucleic acid-based immunotherapy.

Dynamic Changes in Soil Microbial Communities with Glucose Enrichment in Sediment Microbial Fuel Cells.

To investigate soil microbial community dynamics in sediment microbial fuel cells (MFCs), this study applied nonhydric (D) and hydric (S) soils to single-chamber and mediator-free MFCs. Glucose was also used to enrich microorganisms in the soils. The voltage outputs of both the D and S sediment MFCs increased over time but differed from each other. The initial open circuit potentials were 345 and 264 mV for the D and S MFCs. The voltage output reached a maximum of 503 and 604 mV for D and S on days 125 and 131, respectively. The maximum power densities of the D and S MFCs were 2.74 and 2.12 mW m-2, analyzed on day 50. Clustering results revealed that the two groups did not cluster after glucose supplementation and 126 days of MFC function. The change in Geobacter abundance was consistent with the voltage output, indicating that these bacteria may act as the main exoelectrogens on the anode. Spearman correlation analysis demonstrated that, in the D soils, Geobacter was positively correlated with Dialister and negatively correlated with Bradyrhizobium, Kaistobacter, Pedomicrobium, and Phascolarctobacterium; in the S soils, Geobacter was positively correlated with Shewanella and negatively correlated with Blautia. The results suggested that different soil sources in the MFCs and the addition of glucose as a nutrient produced diverse microbial communities with varying voltage output efficiencies. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12088-021-00959-x.

A new drug design strategy: Killing drug resistant bacteria by deactivating their hypothetical genes.

Despite that a bacterial genome is complicated by large numbers of horizontally transferred (HT) genes and function unknown hypothetical (FUN) genes, the Genic-Transcriptional-Stop-Signals-Ratio (TSSR) of a genome shows that HT and FUN genes are complementary to all other genes in the genome. When HT or certain FUN genes are omitted from the Escherichia coli K-12 genome, its Genomic-TSSR value becomes totally incomparable to other E. coli strains. The Genic-TSSR correlation tree of a pathogen shows that some FUN genes would form a unique cluster. Removing these genes by site-specific mutation or gene-knockout should lead to the demise of this pathogen.

Seasonal changes in bacterial communities associated with healthy and diseased Porites coral in southern Taiwan.

We compared the bacterial communities associated with healthy scleractinian coral Porites sp. with those associated with coral infected with pink spot syndrome harvested during summer and winter from waters off the coast of southern Taiwan. Members of the bacterial community associated with the coral were characterized by means of denaturing gradient gel electrophoresis (DGGE) of a short region of the 16S rRNA gene and clone library analysis. Of 5 different areas of the 16S rRNA gene, we demonstrated that the V3 hypervariable region is most suited to represent the coral-associated bacterial community. The DNA sequences of 26 distinct bands extracted from DGGE gels and 269 sequences of the 16S rRNA gene from clone libraries were determined. We found that the communities present in diseased coral were more heterogeneous than the bacterial communities of uninfected coral. In addition, bacterial communities associated with coral harvested in the summer were more diverse than those associated with coral collected in winter, regardless of the health status of the coral. Our study suggested that the compositions of coral-associated bacteria communities are complex, and the population of bacteria varies greatly between seasons and in coral of differing health status.

Impact of a Pediatric Dermatology Service on Emergency Department Utilization for Children with Dermatitis.

BACKGROUND: Atopic dermatitis (AD) is the most common chronic pediatric skin disease, and it can profoundly affect a family's quality of life. Children with flaring AD often seek treatment in emergency departments (EDs), which leads to expensive care and ineffective long-term disease control. OBJECTIVES: The objective of the current study was to determine the effect of a pediatric dermatology service (PDS) on ED use and charges and of disease outcomes for patients diagnosed with AD before and after establishing an intramural PDS. METHODS: This retrospective study reviewed electronic medical records of patients presenting to an urban children's hospital ED with diagnoses encompassing the terms AD, eczema, dermatitis and International Classification of Diseases, Ninth Revision (ICD-9) codes 691.8 and 692.9 during the year before (pre-PDS period) and 3 years after establishing a PDS. RESULTS: There were 205 ED visits for dermatitis in the pre-PDS period and 130 in the with-PDS period, a 36.6% decrease (p < 0.001). In the pre-PDS period, 53.7% (n = 110/205) of patients presenting to the ED had moderate dermatitis, compared with 26.2% (n = 34/130) in the with-PDS period, a 69.1% decrease (p < 0.001). Total ED charges were $142,885 for the pre-PDS period and $90,610 for the with-PDS period, a $52,275 decrease. CONCLUSIONS: This study provides a salient example of achieving the triple aim of health care reform: improving health outcomes (decreased ED visits) improving the patient experience (transitioning care from the ED to the more appropriate ambulatory clinical setting), and decreasing the cost of care (decreased ED charges).

Combinational effect of mutational bias and translational selection for translation efficiency in tomato (Solanum lycopersicum) cv. Micro-Tom.

We conducted a comprehensive analysis of codon usage bias (CUB) based on the available non-redundant full-length cDNA (nrFLcDNA) and expressed sequence tags (ESTs) data of cultivar Micro-Tom and evaluated the associations of observed CUB and measurements of transcriptional and translational effectiveness. The analysis presented in our study suggests a correlation, which is negative but highly correlated between Axis 1 and GC3s (r=-0.827, P<0.01), indicating that mutational bias has a significant and dominant repressive role to the choices of GC3. We also observed a strong positive correlation between codon adaptation index (CAI) and translational adaptation index (tAIg) (0.407, P<0.01), which demonstrates the facilitation of efficient translation by the optimal codon usage patterns of the highly expressed genes. We believe that the complete set of optimal codon usage patterns detected in this study will serve as a model to enhance the transgenesis in the studied cultivar of Solanum lycopersicum.

The effect of Mn(II) on the autoinducing growth inhibition factor in Deinococcus radiodurans.

Decreases in cell division at the stationary phase in bacterial cultures are often due to the depletion of nutrients and/or accumulation of toxic waste products. Yet, during the stationary phase, the highly radiation-resistant bacterium Deinococcus radiodurans undergoes new rounds of cell division when Mn(II) is added to the medium in a phenomenon known as manganese-induced cell division (MnCD). When cells were cultured in medium without Mn(II)-enrichment, a heat-resistant, proteinase K-resistant factor (or factors) with a molecular mass less than 10 kD accumulated in the spent medium. Inclusion of the concentrated spent medium in fresh medium could inhibit the growth of D. radiodurans significantly, and the degree of inhibition was dose dependent. However, the relative stimulatory effect of MnCD was also dose dependent-the higher the inhibition, the stronger was the MnCD response. Previous studies have shown that nutrients were not limiting and deinococcal cells would continue metabolizing its nutrients at stationary phase. Cells became more sensitive to radiation when nutrients in the medium eventually became depleted. We speculated that D. radiodurans might produce this factor in the medium to control its population density. The reduction in cell population would conserve the nutrients that in turn might enhance the survival of the species.

Picoplankton dynamics and picoeukaryote diversity in a hyper-eutrophic subtropical lagoon.

Picoplankton (cells with a diameter of 0.2-3.0 µm) is the dominant contributor to both primary production and biomass in the ocean. Most of the previous studies on picoplankton have been conducted in the oligotrophic open sea with few in the eutrophic area. In this study, we investigated the dynamics of different groups of picoplankton and the diversity of picoeukaryote (based on 18S rDNA) in a hyper-eutrophic marine coastal lagoon. The results indicated that temperature and phosphate concentration were most responsible for the dynamics of different picoplankton groups. Examination of 135 clones revealed 27 different Denaturing Gradient Gel Electrophoresis (DGGE) patterns. At least 7 high-level taxonomic groups of picoeukaryote were recorded. The picoeukaryotic diversities included Alveolates, Stramenopiles, Haptophyceae, and Viridiplantae, with Stramenopiles being the most diverse group. Overall the results of this study indicated that picoplankton diversity was low relative to studies conducted in more oligotrophic waters.

Improved Targeting and Safety of Doxorubicin through a Novel Albumin Binding Prodrug Approach.

Human serum albumin (HSA) improves the pharmacokinetic profile of drugs attached to it, making it an attractive carrier with proven clinical success. In our previous studies, we have shown that Caveolin-1 (Cav-1) and caveolae-mediated endocytosis play important roles in the uptake of HSA and albumin-bound drugs. Doxorubicin is an FDA-approved chemotherapeutic agent that is effective against multiple cancers, but its clinical applicability has been hampered by its high toxicity levels. In this study, a doxorubicin-prodrug was developed that could independently and avidly bind HSA in circulation, called IPBA-Dox. We first developed and characterized IPBA-Dox and confirmed that it can bind albumin in vitro while retaining a potent cytotoxic effect. We then verified that it efficiently binds to HSA in circulation, leading to an improvement in the pharmacokinetic profile of the drug. In addition, we tested our prodrug for Cav-1 selectivity and found that it preferentially affects cells that express relatively higher levels of Cav-1 in vitro and in vivo. Moreover, we found that our compound was well tolerated in vivo at concentrations at which doxorubicin was lethal. Altogether, we have developed a doxorubicin-prodrug that can successfully bind HSA, retaining a strong cytotoxic effect that preferentially targets Cav-1 positive cells while improving the general tolerability of the drug.

Different microbial communities in paddy soils under organic and nonorganic farming.

Organic agriculture is a farming method that provides healthy food and is friendly to the environment, and it is developing rapidly worldwide. This study compared microbial communities in organic farming (Or) paddy fields to those in nonorganic farming (Nr) paddy fields based on 16S rDNA sequencing and analysis. The predominant microorganisms in both soils were Proteobacteria, Chloroflexi, Acidobacteria, Actinobacteria, and Nitrospirota. The alpha diversity of the paddy soil microbial communities was not different between the nonorganic and organic farming systems. The beta diversity of nonmetric multidimensional scaling (NMDS) revealed that the two groups were significantly separated. Distance-based redundancy analysis (db-RDA) suggested that soil pH and electrical conductivity (EC) had a positive relationship with the microbes in organic paddy soils. There were 23 amplicon sequence variants (ASVs) that showed differential abundance. Among them, g_B1-7BS (Proteobacteria), s_Sulfuricaulis limicola (Proteobacteria), g_GAL15 (p_GAL15), c_Thermodesulfovibrionia (Nitrospirota), two of f_Anaerolineaceae (Chloroflexi), and two of g_S085 (Chloroflexi) showed that they were more abundant in organic soils, whereas g_11-24 (Acidobacteriota), g__Subgroup_7 (Acidobacteriota), and g_Bacillus (Firmicutes) showed differential abundance in nonorganic paddy soils. Functional prediction of microbial communities in paddy soils showed that functions related to carbohydrate metabolism could be the major metabolic activities. Our work indicates that organic farming differs from nonorganic farming in terms of microbial composition in paddy soils and provides specific microbes that might be helpful for understanding soil fertility.

Bioactive secondary metabolites of a marine Bacillus sp. inhibit superoxide generation and elastase release in human neutrophils by blocking formyl peptide receptor 1.

It is well known that overwhelming neutrophil activation is closely related to acute and chronic inflammatory injuries. Formyl peptide receptor 1 (FPR1) plays an important role in activation of neutrophils and may represent a potent therapeutic target in inflammatory diseases. In the present study, we demonstrated that IA-LBI07-1 (IA), an extract of bioactive secondary metabolites from a marine Bacillus sp., has anti-inflammatory effects in human neutrophils. IA significantly inhibited superoxide generation and elastase release in formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP)-activated neutrophils, but failed to suppress the cell responses activated by non-FPR1 agonists. IA did not alter superoxide production and elastase activity in cell-free systems. IA also attenuated the downstream signaling from FPR1, such as the Ca2+, MAP kinases and AKT pathways. In addition, IA inhibited the binding of N-formyl-Nle-Leu-Phe-Nle-Tyr-Lys-fluorescein, a fluorescent analogue of FMLP, to FPR1 in human neutrophils and FPR1-transfected HEK293 cells. Taken together, these results show that the anti-inflammatory effects of IA in human neutrophils are through the inhibition of FPR1. Also, our data suggest that IA may have therapeutic potential to decrease tissue damage induced by human neutrophils.

Iron Fertilization Can Enhance the Mass Production of Copepod, Pseudodiaptomus annandalei, for Fish Aquaculture.

Copepods are proven nutritious food sources for the mariculture/larviculture industry, however, unreliable methods for mass production of copepods are a major bottleneck. In this study, we modified a previously reported inorganic fertilization method (N: 700 µg L-1 and P: 100 µg L-1) by the addition of iron (Fe: 10 µg L-1, using FeSO4·7H2O) (+Fe treatment) and compared its suitability for copepod culture (Pseudodiaptomus annandalei) to the original method (control). The experiment was conducted outdoors in 1000 L tanks for 15 days. The addition of iron prolonged the growth phase of the phytoplankton and resulted in the production of significantly more small phytoplankton (0.45-20 µm, average 2.01 ± 0.52 vs. 9.03 ± 4.17 µg L-1 in control and +Fe, respectively) and adult copepods (control: 195 ± 35, +Fe: 431 ± 109 ind L-1), whereas copepodid-stage was similar between treatments (control: 511 ± 107 vs. +Fe: 502 ± 68 ind L-1). Although adding iron increased the cost of production by 23% compared to the control, the estimated net profit was 97% greater. We concluded that inorganic fertilization, with the addition of iron (Fe: 10 µg L-1), could be an effective method for the mass production of copepods for larviculture.

Functional Prediction of Microbial Communities in Sediment Microbial Fuel Cells.

Sediment microbial fuel cells (MFCs) were developed in which the complex substrates present in the sediment could be oxidized by microbes for electron production. In this study, the functional prediction of microbial communities of anode-associated soils in sediment MFCs was investigated based on 16S rRNA genes. Four computational approaches, including BugBase, Functional Annotation of Prokaryotic Taxa (FAPROTAX), the Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt2), and Tax4Fun2, were applied. A total of 67, 9, 37, and 38 functional features were statistically significant. Among these functional groups, the function related to the generation of precursor metabolites and energy was the only one included in all four computational methods, and the sum total of the proportion was 93.54%. The metabolism of cofactor, carrier, and vitamin biosynthesis was included in the three methods, and the sum total of the proportion was 29.94%. The results suggested that the microbial communities usually contribute to energy metabolism, or the metabolism of cofactor, carrier, and vitamin biosynthesis might reveal the functional status in the anode of sediment MFCs.

Antitumor Activity of Anti-miR-21 Delivered through Lipid Nanoparticles.

The ability of lipid nanoparticles (LNPs) to deliver nucleic acids have shown a great therapeutic potential to treat a variety of diseases. Here, an optimized formulation of QTsome lipid nanoparticles (QTPlus) is utilized to deliver an anti-miR-21 (AM21) against cancer. The miR-21 downstream gene regulation and antitumor activity is evaluated using mouse and human cancer cells and macrophages. The antitumor activity of QTPlus encapsulating AM21 (QTPlus-AM21) is further evaluated in combination with erlotinib and atezolizumab (ATZ). QTPlus-AM21 demonstrates a superior miR-21-dependent gene regulation and eventually inhibits A549 non-small cell lung cancer growth in vitro. QTPlus-AM21 further induces chemo-sensitization of A549 cells to erlotinib with a combination index of 0.6 in inhibiting A549 cell growth. When systemically administers to MC38 tumor-bearing mouse model, QTPlus-AM21 exhibits an antitumor immune response with over 80% tumor growth inhibition (TGI%) and over twofold and fourfold PD-1 and PD-L1 upregulation in tumors and spleens. The combination therapy of QTPlus-AM21 and ATZ further shows a higher antitumor response (TGI% over 90%) and successfully increases M1 macrophages and CD8 T cells into TME. This study provides new insights into the antitumor mechanism of AM21 and shows great promise of QTPlus-AM21 in combination with chemotherapies and immunotherapies.

Optimized Liposomal Delivery of Bortezomib for Advancing Treatment of Multiple Myeloma.

Bortezomib (BTZ), a boronic acid-derived proteasome inhibitor, is commonly employed in treating multiple myeloma (MM). However, the applications of BTZ are limited due to its poor stability and low bioavailability. Herein, we develop an optimized liposomal formulation of BTZ (L-BTZ) by employing a remote-loading strategy. This formulation uses Tiron, a divalent anionic catechol derivative, as the internal complexing agent. Compared to earlier BTZ-related formulations, this alternative formulation showed significantly greater stability due to the Tiron-BTZ complex's higher pH stability and negative charges, compared to the meglumine-BTZ complex. Significantly, the plasma AUC of L-BTZ was found to be 30 times greater than that of free BTZ, suggesting an extended blood circulation duration. In subsequent therapeutic evaluations using two murine xenograft tumor models of MM, the NCI-H929 and OPM2 models showed tumor growth inhibition (TGI) values of 37% and 57%, respectively. In contrast, free BTZ demonstrated TGI values of 17% and 11% in these models. Further, L-BTZ presented enhanced antitumor efficacy in the Hepa1-6 HCC syngeneic model, indicating its potential broader applicability as an antineoplastic agent. These findings suggest that the optimized L-BTZ formulation offers a significant advancement in BTZ delivery, holding substantial promise for clinical investigation in not merely MM, but other cancer types.

Genome dynamics in three different geographical isolates of white spot syndrome virus (WSSV).

White spot syndrome virus (WSSV), the sole member of the monotypic family Nimaviridae, is considered an extremely lethal shrimp pathogen. Despite its impact, some essential biological characteristics related to WSSV genome dynamics, such as the synonymous codon usage pattern and selection pressure in genes, remain to be elucidated. The results show that compositional limitations and mutational pressure determine the codon usage bias and base composition in WSSV. Furthermore, different forces of selective pressure are acting across various regions of the WSSV genome. Finally, this study points out the possible occurrence of two major recombination events.

Mining of miRNAs and potential targets from gene oriented clusters of transcripts sequences of the anti-malarial plant, Artemisia annua.

miRNAs involved in the biosynthesis of artemisinin, an anti-malarial compound form the plant Artemisia annua, have been identified using computational approaches to find conserved pre-miRNAs in available A. annua UniGene collections. Eleven pre-miRNAs were found from nine families. Targets predicted for these miRNAs were mainly transcription factors for conserved miRNAs. No target genes involved in artemisinin biosynthesis were found. However, miR390 was predicted to target a gene involved in the trichome development, which is the site of synthesis of artemisinin and could be a candidate for genetic transformation aiming to increase the content of artemisinin. Phylogenetic analyses were carried out to determinate the relation between A. annua and other plant pre-miRNAs: the pre-miRNA-based phylogenetic trees failed to correspond to known phylogenies, suggesting that pre-miRNA primary sequences may be too variable to accurately predict phylogenetic relations.

Pseudoalteromone B: a novel 15C compound from a marine bacterium Pseudoalteromonas sp. CGH2XX.

A novel 15C compound, pseudoalteromone B (1), possessing a novel carbon skeleton, was obtained from a marine bacterium Pseudoalteromonas sp. CGH2XX. This bacterium was originally isolated from a cultured-type octocoral Lobophytum crassum, that was growing in cultivating tanks equipped with a flow-through sea water system. The structure of 1 was established by spectroscopic methods. Pseudoalteromone B (1) displayed a modestly inhibitory effect on the release of elastase by human neutrophils.

Isolation of marine bacteria with antimicrobial activities from cultured and field-collected soft corals.

Bacteria associated with eight field-collected and five cultured soft corals of Briareum sp., Sinularia sp., Sarcophyton sp., Nephtheidae sp., and Lobophytum sp. were screened for their abilities in producing antimicrobial metabolites. Field-collected coral samples were collected from Nanwan Bay in southern Taiwan. Cultured corals were collected from the cultivating tank at National Museum of Marine Biology and Aquarium. A total of 1,526 and 1,138 culturable, heterotrophic bacteria were isolated from wild and cultured corals, respectively; seawater requirement and antimicrobial activity were then assessed. There is no significant difference between the ratio of seawater-requiring bacteria on the wild and cultured corals. The ratio of antibiotic-producing bacteria within the seawater-requiring bacteria did not differ between the corals. Nineteen bacterial strains that showed high antimicrobial activity were selected for 16S rDNA sequencing. Three strains could be assigned at the family level (Rhodobacteraceae). The remaining 16 strains belong to eight genera: Marinobacterium (2 strains), Pseudoalteromonas (1), Vibrio (5), Enterovibrio (1), Tateyamaria (1), Labrenzia (2), and Pseudovibrio (4). The crude extract from bacteria strains CGH2XX was found to have high cytotoxicity against the cancer cell line HL-60 (IC(50) = 0.94 µg/ml) and CCRF-CEM (IC(50) = 1.19 µg/ml). Our results demonstrate that the marine bacteria from corals have great potential in the discovery of useful medical molecules.