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1.
Arch Microbiol ; 206(8): 354, 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39017726

ABSTRACT

Titanium implants are subject to bacterial adhesion and peri-implantitis induction, and biosurfactants bring a new alternative to the fight against infections. This work aimed to produce and characterize the biosurfactant from Bacillus subtilis ATCC 19,659, its anti-adhesion and antimicrobial activity, and cell viability. Anti-adhesion studies were carried out against Streptococcus sanguinis, Staphylococcus aureus, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Proteus mirabilis as the minimum inhibitory concentration and the minimum bactericidal concentration. Cell viability was measured against osteoblast and fibroblast cells. The biosurfactant was classified as lipopeptide, with critical micelle concentration at 40 µg mL- 1, and made the titanium surface less hydrophobic. The anti-adhesion effect was observed for Staphylococcus aureus and Streptococcus sanguinis with 54% growth inhibition and presented a minimum inhibitory concentration of 15.7 µg mL- 1 for Streptococcus sanguinis and Aggregatibacter actinomycetemcomitans. The lipopeptide had no cytotoxic effect and demonstrated high potential application against bacterial biofilms.


Subject(s)
Bacterial Adhesion , Biofilms , Dental Implants , Lipopeptides , Microbial Sensitivity Tests , Titanium , Titanium/pharmacology , Titanium/chemistry , Biofilms/drug effects , Biofilms/growth & development , Bacterial Adhesion/drug effects , Dental Implants/microbiology , Lipopeptides/pharmacology , Humans , Anti-Bacterial Agents/pharmacology , Staphylococcus aureus/drug effects , Staphylococcus aureus/physiology , Bacillus subtilis/drug effects , Porphyromonas gingivalis/drug effects , Porphyromonas gingivalis/physiology , Porphyromonas gingivalis/growth & development , Aggregatibacter actinomycetemcomitans/drug effects , Surface Properties , Fibroblasts/drug effects , Fusobacterium nucleatum/drug effects , Cell Survival/drug effects , Osteoblasts/drug effects , Surface-Active Agents/pharmacology
2.
Eur J Pharm Biopharm ; 197: 114212, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38342421

ABSTRACT

Capsaicin (CAP) has been implicated as a gastroprotective agent in the treatment of peptic ulcers. However, its oral administration is hampered by its poor aqueous solubility and caustic effect at high administered doses. To address these limitations, we describe the development of gastric floating, sustained release electrospun films loaded with CAP. The nanofiber films were formulated using the polymers Eudragit RL/RS and sodium bicarbonate (SB) as the effervescent agent. The films were tested for their physicochemical properties, and film buoyancy and in vitro release of CAP were assessed in simulated gastric fluid. The cytocompatibility and anti-inflammatory properties of the films were evaluated in lipopolysaccharide (LPS)-stimulated Caco-2 cells. The amorphous films showed improved wettability, a short floating lag time (<1 s) and a total floating time of over 24 h accompanied by sustained CAP release for up to 24 h. CAP-loaded films demonstrated biocompatibility with Caco-2 cells and potential cytoprotective effects by attenuating inflammatory cytokine and reactive oxygen species (ROS) production in LPS-stimulated Caco-2 cells. The gastric floating electrospun films could serve as a platform for sustained and stomach-specific drug delivery applications.


Subject(s)
Capsaicin , Lipopolysaccharides , Humans , Delayed-Action Preparations/chemistry , Caco-2 Cells , Drug Delivery Systems , Solubility , Tablets
3.
Cell Mol Bioeng ; 16(4): 383-392, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37810998

ABSTRACT

Introduction: Multiple myeloma (MM) is a hematological blood cancer of the bone marrow that remains largely incurable, in part due to its physical interactions with the bone marrow microenvironment. Such interactions enhance the homing, proliferation, and drug resistance of MM cells. Specifically, adhesion receptors and homing factors, E-selectin (ES) and cyclophilin A (CyPA), respectively, expressed by bone marrow endothelial cells enhance MM colonization and dissemination. Thus, silencing of ES and CyPA presents a potential therapeutic strategy to evade MM spreading. However, small molecule inhibition of ES and CyPA expressed by bone marrow endothelial cells remains challenging, and blocking antibodies induce further MM propagation. Therefore, ES and CyPA are promising candidates for inhibition via RNA interference (RNAi). Methods: Here, we utilized a previously developed lipid-polymer nanoparticle for RNAi therapy, that delivers siRNA to the bone marrow perivascular niche. We utilized our platform to co-deliver ES and CyPA siRNAs to prevent MM dissemination in vivo. Results: Lipid-polymer nanoparticles effectively downregulated ES expression in vitro, which decreased MM cell adhesion and migration through endothelial monolayers. Additionally, in vivo delivery of lipid-polymer nanoparticles co-encapsulating ES and CyPA siRNA extended survival in a xenograft mouse model of MM, either alone or in combination with the proteasome inhibitor bortezomib. Conclusions: Our combination siRNA lipid-polymer nanoparticle therapy presents a vascular microenvironment-targeting strategy as a potential paradigm shift for MM therapies, which could be extended to other cancers that colonize the bone marrow. Supplementary Information: The online version contains supplementary material available at 10.1007/s12195-023-00774-y.

4.
Proc Natl Acad Sci U S A ; 120(25): e2215711120, 2023 06 20.
Article in English | MEDLINE | ID: mdl-37310997

ABSTRACT

Multiple myeloma (MM), a hematologic malignancy that preferentially colonizes the bone marrow, remains incurable with a survival rate of 3 to 6 mo for those with advanced disease despite great efforts to develop effective therapies. Thus, there is an urgent clinical need for innovative and more effective MM therapeutics. Insights suggest that endothelial cells within the bone marrow microenvironment play a critical role. Specifically, cyclophilin A (CyPA), a homing factor secreted by bone marrow endothelial cells (BMECs), is critical to MM homing, progression, survival, and chemotherapeutic resistance. Thus, inhibition of CyPA provides a potential strategy to simultaneously inhibit MM progression and sensitize MM to chemotherapeutics, improving therapeutic response. However, inhibiting factors from the bone marrow endothelium remains challenging due to delivery barriers. Here, we utilize both RNA interference (RNAi) and lipid-polymer nanoparticles to engineer a potential MM therapy, which targets CyPA within blood vessels of the bone marrow. We used combinatorial chemistry and high-throughput in vivo screening methods to engineer a nanoparticle platform for small interfering RNA (siRNA) delivery to bone marrow endothelium. We demonstrate that our strategy inhibits CyPA in BMECs, preventing MM cell extravasation in vitro. Finally, we show that siRNA-based silencing of CyPA in a murine xenograft model of MM, either alone or in combination with the Food and Drug Administration (FDA)-approved MM therapeutic bortezomib, reduces tumor burden and extends survival. This nanoparticle platform may provide a broadly enabling technology to deliver nucleic acid therapeutics to other malignancies that home to bone marrow.


Subject(s)
Multiple Myeloma , United States , Humans , Animals , Mice , Multiple Myeloma/drug therapy , Multiple Myeloma/genetics , Bone Marrow , RNA, Small Interfering/genetics , Endothelial Cells , Cyclophilin A , Lipids , Tumor Microenvironment
5.
Stem Cell Rev Rep ; 19(4): 906-927, 2023 05.
Article in English | MEDLINE | ID: mdl-36585572

ABSTRACT

Hematopoietic stem cells are maintained in a specialized microenvironment, known as the 'niche', within the bone marrow. Understanding the contribution of cellular and molecular components within the bone marrow niche for the maintenance of hematopoietic stem cells is crucial for the success of therapeutic applications. So far, the roles of crucial mechanisms within the bone marrow niche have been explored in transgenic animals in which genetic modifications are ubiquitously introduced in the whole body. The lack of precise tools to explore genetic alterations exclusively within the bone marrow prevents our determination of whether the observed outcomes result from confounding effects from other organs. Here, we developed a new method - 'whole bone subcutaneous transplantation'- to study the bone marrow niche in transgenic animals precisely. Using immunolabeling of CD45.1 (donor) vs. CD45.2 (recipient) hematopoeitic stem cells, we demonstrated that hematopoeitic stem cells from the host animals colonize the subcutaneously transplanted femurs after transplantation, while the hematopoietic stem cells from the donor disappear. Strikinlgy, the bone marrow niche of these subcutaneously transplanted femurs remain from the donor mice, enabling us to study specifically cells of the bone marrow niche using this model. We also showed that genetic ablation of peri-arteriolar cells specifically in donor femurs reduced the numbers of hematopoietic stem cells in these bones. This supports the use of this strategy as a model, in combination with genetic tools, to evaluate how bone marrow niche specific modifications may impact non-modified hematopoietic stem cells. Thus, this approach can be utilized for genetic manipulation in vivo of specific cell types only within the bone marrow. The combination of whole bone subcutaneous transplantation with rodent transgenic models will facilitate a more precise, complex and comprehensive understanding of existing problems in the study of the hematopoietic stem cell bone marrow niche.


Subject(s)
Bone Marrow , Hematopoietic Stem Cell Transplantation , Mice , Animals , Hematopoietic Stem Cells/metabolism , Bone Marrow Transplantation , Bone and Bones
6.
Angiogenesis ; 26(1): 129-166, 2023 02.
Article in English | MEDLINE | ID: mdl-36183032

ABSTRACT

Cancer cells are embedded within the tissue and interact dynamically with its components during cancer progression. Understanding the contribution of cellular components within the tumor microenvironment is crucial for the success of therapeutic applications. Here, we reveal the presence of perivascular GFAP+/Plp1+ cells within the tumor microenvironment. Using in vivo inducible Cre/loxP mediated systems, we demonstrated that these cells derive from tissue-resident Schwann cells. Genetic ablation of endogenous Schwann cells slowed down tumor growth and angiogenesis. Schwann cell-specific depletion also induced a boost in the immune surveillance by increasing tumor-infiltrating anti-tumor lymphocytes, while reducing immune-suppressor cells. In humans, a retrospective in silico analysis of tumor biopsies revealed that increased expression of Schwann cell-related genes within melanoma was associated with improved survival. Collectively, our study suggests that Schwann cells regulate tumor progression, indicating that manipulation of Schwann cells may provide a valuable tool to improve cancer patients' outcomes.


Subject(s)
Neoplasms , Neuroglia , Humans , Retrospective Studies , Neuroglia/metabolism , Schwann Cells/metabolism , Schwann Cells/pathology , Pericytes , Tumor Microenvironment/physiology , Neoplasms/pathology
7.
G3 (Bethesda) ; 12(12)2022 12 01.
Article in English | MEDLINE | ID: mdl-36205610

ABSTRACT

Amphibians are increasingly threatened worldwide, but the availability of genomic resources that could be crucial for implementing informed conservation practices lags well behind that for other vertebrate groups. Here, we describe draft de novo genome, mitogenome, and transcriptome assemblies for the Neotropical leaf-frog Phyllomedusa bahiana native to the Brazilian Atlantic Forest and Caatinga. We used a combination of PacBio long reads and Illumina sequencing to produce a 4.74-Gbp contig-level genome assembly, which has a contiguity comparable to other recent nonchromosome level assemblies. The assembled mitogenome comprises 16,239 bp and the gene content and arrangement are similar to other Neobratrachia. RNA-sequencing from 8 tissues resulted in a highly complete (86.3%) reference transcriptome. We further use whole-genome resequencing data from P. bahiana and from its sister species Phyllomedusa burmeisteri, to demonstrate how our assembly can be used as a backbone for population genomics studies within the P. burmeisteri species group. Our assemblies thus represent important additions to the catalog of genomic resources available from amphibians.


Subject(s)
Genome , Transcriptome , Animals , Genomics/methods , Sequence Analysis, RNA/methods , High-Throughput Nucleotide Sequencing/methods , Anura/genetics , Plant Leaves
8.
Int Immunopharmacol ; 110: 108952, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35716482

ABSTRACT

Visceral leishmaniasis (VL) is an infectious disease caused by Leishmania infantum (L. infantum). Currently, there are no vaccines and/or prophylactic therapies against VL, and the recentpharmacological approaches come from the drug repositioning strategy. Here, we evaluated the anticancer drug pamidronate (PAM) to identify a new therapeutic option for the treatment of human VL. We assessed its in vitro antileishmanial activity against the promastigote and amastigote forms of L. infantum by evaluating cell cytotoxicity. The antileishmanial and immunomodulatory activities were assessed using human peripheral blood leukocytes ex vivo. PAM induced the formation of vacuoles in the cytoplasm of the promastigotes and alterations in the morphology of the kinetoplast and mitochondria in vitro, which indicates anti-promastigote activity. PAM also reduced the number of infected macrophages and intracellular amastigotes in a concentration-dependent manner, with cell viability above 70%. In ex vivo, PAM reduced the internalized forms of L. infantum in the classical monocyte subpopulation. Furthermore, it enhanced IL-12 and decreased IL-10 and TGF-ß by monocytes and neutrophils. Increased IFN-γ and TNF levels for CD8- and CD8+ T lymphocytes and B lymphocytes, respectively, were observed after the treatment with PAM, as well as a reduction in IL-10 by the lymphocyte subpopulations evaluated. Taken together, our results suggest that PAM may be eligible as a potential therapeutic alternative for drug repurposing to treat human visceral leishmaniasis.


Subject(s)
Antiprotozoal Agents , Leishmania infantum , Leishmaniasis, Visceral , Leishmaniasis , Animals , Antiprotozoal Agents/pharmacology , Antiprotozoal Agents/therapeutic use , Drug Repositioning , Humans , Interleukin-10/therapeutic use , Leishmaniasis/drug therapy , Leishmaniasis, Visceral/drug therapy , Mice , Mice, Inbred BALB C , Pamidronate
9.
Pharmaceutics ; 14(5)2022 May 05.
Article in English | MEDLINE | ID: mdl-35631575

ABSTRACT

Liposomal amphotericin B (AmB) or AmBisome® is the most effective and safe therapeutic agent for visceral leishmaniasis (VL), but its clinical efficacy is limited in cutaneous leishmaniasis (CL) and HIV/VL co-infection. The aim of this work was to develop a formulation of AmB in PEGylated liposomes and compare its efficacy to AmBisome® in a murine model of CL. Formulations of AmB in conventional and PEGylated liposomes were characterized for particle size and morphology, drug encapsulation efficiency and aggregation state. Those were compared to AmBisome® in Leishmania amazonensis-infected BALB/c mice for their effects on the lesion size growth and parasite load. The conventional and PEGylated formulations showed vesicles with 100-130 nm diameter and low polydispersity, incorporating more than 95% of AmB under the non-aggregated form. Following parenteral administration in the murine model of CL, the PEGylated formulation of AmB significantly reduced the lesion size growth and parasite load, in comparison to control groups, in contrast to conventional liposomal AmB. The PEGylated formulation of AmB was also effective when given by oral route on a 2-day regimen. This work reports for the first time that PEGylated liposomal AmB can improve the treatment of experimental cutaneous leishmaniasis by both parenteral and oral routes.

10.
Adv Physiol Educ ; 46(3): 351-357, 2022 Sep 01.
Article in English | MEDLINE | ID: mdl-35549509

ABSTRACT

The COVID-19 pandemic affected almost all aspects of our lives, including the education sector and the way of teaching and learning. In March 2020, health authorities in Brazil imposed social isolation and the interruption of on-site activities in schools and universities. In this context, the Federal University of Minas Gerais (UFMG), one of the largest universities in Brazil and Latin America, developed an emergency remote learning (ERL) plan that allowed the return of classes in an online format and supported students to obtain access to equipment and internet network. Within this new perspective, the Undergraduate Teaching Assistant (UTA) program of the Department of Physiology and Biophysics (DFIB) explored strategies to minimize the impact of the absence of face-to-face classes. Using different available tools in online platforms and social media such as Microsoft Teams, YouTube animated video classes, and Instagram, the UTA program assisted >500 undergraduate students and strongly supported professors during ERL. In just over a year, our video classes on YouTube Channel reached ∼40,000 views. Most of the students reported that their questions were fully and quickly solved by the UTA program. Collectively, our results indicate that the strategies implemented by the UTA program helped the undergraduate students and professors to adapt to a remote learning format.


Subject(s)
COVID-19 , Education, Distance , Biophysics , Education, Distance/methods , Humans , Pandemics , Students
11.
J Funct Biomater ; 13(2)2022 Apr 18.
Article in English | MEDLINE | ID: mdl-35466227

ABSTRACT

The quest for an ideal biomaterial perfectly matching the microenvironment of the surrounding tissues and cells is an endless challenge within biomedical research, in addition to integrating this with a facile and sustainable technology for its preparation. Engineering hydrogels through click chemistry would promote the sustainable invention of tailor-made hydrogels. Herein, we disclose a versatile and facile catalyst-free click chemistry for the generation of an innovative hydrogel by combining chondroitin sulfate (CS) and polyethylene glycol (PEG). Various multi-armed PEG-Norbornene (A-PEG-N) with different molecular sizes were investigated to generate crosslinked copolymers with tunable rheological and mechanical properties. The crosslinked and mechanically stable porous hydrogels could be generated by simply mixing the two clickable Tetrazine-CS (TCS) and A-PEG-N components, generating a self-standing hydrogel within minutes. The leading candidate (TCS-8A-PEG-N (40 kD)), based on the mechanical and biocompatibility results, was further employed as a scaffold to improve wound closure and blood flow in vivo. The hydrogel demonstrated not only enhanced blood perfusion and an increased number of blood vessels, but also desirable fibrous matrix orientation and normal collagen deposition. Taken together, these results demonstrate the potential of the hydrogel to improve wound repair and hold promise for in situ skin tissue engineering applications.

12.
Acta Neuropathol Commun ; 9(1): 183, 2021 11 16.
Article in English | MEDLINE | ID: mdl-34784974

ABSTRACT

Sensory neurons have recently emerged as components of the tumor microenvironment. Nevertheless, whether sensory neuronal activity is important for tumor progression remains unknown. Here we used Designer Receptors Exclusively Activated by a Designer Drug (DREADD) technology to inhibit or activate sensory neurons' firing within the melanoma tumor. Melanoma growth and angiogenesis were accelerated following inhibition of sensory neurons' activity and were reduced following overstimulation of these neurons. Sensory neuron-specific overactivation also induced a boost in the immune surveillance by increasing tumor-infiltrating anti-tumor lymphocytes, while reducing immune-suppressor cells. In humans, a retrospective in silico analysis of melanoma biopsies revealed that increased expression of sensory neurons-related genes within melanoma was associated with improved survival. These findings suggest that sensory innervations regulate melanoma progression, indicating that manipulation of sensory neurons' activity may provide a valuable tool to improve melanoma patients' outcomes.


Subject(s)
Melanoma/genetics , Melanoma/pathology , Sensory Receptor Cells/pathology , Animals , Behavior, Animal/drug effects , Biopsy , Cell Line, Tumor , Computer Simulation , Disease Progression , Humans , Immunologic Surveillance , Lymphocytes/pathology , Melanoma, Experimental/genetics , Melanoma, Experimental/pathology , Mice , Mice, Transgenic , NAV1.8 Voltage-Gated Sodium Channel/genetics , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/pathology , Sensory Receptor Cells/metabolism , Suppressor Factors, Immunologic , Tumor Microenvironment
13.
Nat Biomed Eng ; 4(11): 1076-1089, 2020 11.
Article in English | MEDLINE | ID: mdl-33020600

ABSTRACT

Bone-marrow endothelial cells in the haematopoietic stem-cell niche form a network of blood vessels that regulates blood-cell traffic as well as the maintenance and function of haematopoietic stem and progenitor cells. Here, we report the design and in vivo performance of systemically injected lipid-polymer nanoparticles encapsulating small interfering RNA (siRNA), for the silencing of genes in bone-marrow endothelial cells. In mice, nanoparticles encapsulating siRNA sequences targeting the proteins stromal-derived factor 1 (Sdf1) or monocyte chemotactic protein 1 (Mcp1) enhanced (when silencing Sdf1) or inhibited (when silencing Mcp1) the release of stem and progenitor cells and of leukocytes from the bone marrow. In a mouse model of myocardial infarction, nanoparticle-mediated inhibition of cell release from the haematopoietic niche via Mcp1 silencing reduced leukocytes in the diseased heart, improved healing after infarction and attenuated heart failure. Nanoparticle-mediated RNA interference in the haematopoietic niche could be used to investigate haematopoietic processes for therapeutic applications in cancer, infection and cardiovascular disease.


Subject(s)
Drug Delivery Systems/methods , Gene Silencing/drug effects , Hematopoietic Stem Cells/drug effects , Nanoparticles/administration & dosage , Nanoparticles/chemistry , RNA, Small Interfering/administration & dosage , RNA, Small Interfering/chemistry , Stem Cell Niche/genetics , Animals , Bone Marrow Cells/drug effects , Bone Marrow Cells/metabolism , Cells, Cultured , Disease Models, Animal , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Hematopoietic Stem Cells/metabolism , Mice, Inbred C57BL , Myocardial Infarction/prevention & control
14.
J Inorg Biochem ; 206: 111017, 2020 05.
Article in English | MEDLINE | ID: mdl-32120160

ABSTRACT

Cancer-Associated Fibroblasts (CAFs) contribute to tumour progression and have received significant attention as a therapeutic target. These cells produce growth factors, cytokines and chemokines, stimulating cancer cell proliferation and inhibiting their apoptosis. Recent advances in drug delivery have demonstrated a significant promise of iron oxide nanoparticles in clinics as theranostic agents, mainly due to their magnetic properties. Here, we designed superparamagnetic iron oxide nanoparticles (SPIONs) to induce apoptosis of human fibroblasts. SPIONs were synthesized via co-precipitation method and coated with sodium citrate (SPION_Cit). We assessed the intracellular uptake of SPIONs by human fibroblast cells, as well as their cytotoxicity and ability to induce thermal effects under the magnetic field. The efficiency and time of nanoparticle internalization were assessed by Prussian Blue staining, flow cytometry and transmission electron microscopy. SPIONs_Cit were detected in the cytoplasm of human fibroblasts 15 min after in vitro exposure, entering into cells mainly via endocytosis. Analyses through Cell Titer Blue assay, AnnexinV-fluorescein isothiocyanate (FITC) and propidium iodide (PI) cellular staining demonstrated that concentrations below 8 × 10-2 mg/mL of SPIONs_Cit did not alter cell viability of human fibroblast. Furthermore, it was also demonstrated that SPIONs_Cit associated with alternating current magnetic field were able to induce hyperthermia and human fibroblast cell death in vitro, mainly through apoptosis (83.5%), activating caspase 8 (extrinsic apoptotic via) after a short exposure period. Collectively these findings suggest that our nanoplatform is biocompatible and can be used for therapeutic purposes in human biological systems, such as inducing apoptosis of CAFs.


Subject(s)
Apoptosis/drug effects , Ferric Compounds/pharmacology , Fibroblasts/drug effects , Magnetic Iron Oxide Nanoparticles/administration & dosage , Cancer-Associated Fibroblasts/drug effects , Cell Death/drug effects , Cell Line , Cell Survival/drug effects , Citric Acid/chemistry , Endocytosis , Ferric Compounds/chemistry , Flow Cytometry , Humans , Hyperthermia, Induced , Magnetic Iron Oxide Nanoparticles/chemistry , Microscopy, Electron, Transmission , Neoplasms/metabolism , Neoplasms/pathology
15.
PLoS One ; 15(2): e0229324, 2020.
Article in English | MEDLINE | ID: mdl-32084229

ABSTRACT

Taxonomists always have had intense discussions about how species should be delimited and recently many studies have used integrative approaches by combining molecular, morphological, and bioacoustic data. Although these studies are paramount for understanding species diversity, few of them actually formalize species delimitations to the final step of nomenclatural acts. Historically, the Neotropical frog genus Adenomera has been considered as a difficult taxonomic group because it comprises many morphologically similar species exhibiting high levels of intraspecific polymorphism. A recent work using molecular data shed light on the phylogenetic relationships within the genus and identified several lineages that may correspond to undescribed species but did not delimit species boundaries. In the Atlantic Forest, a clade formed by A. marmorata and two putative species (Adenomera sp. J and Adenomera sp. K) were identified. In this paper, we combine morphological, acoustic, and molecular data in order to evaluate species limits within this Atlantic Forest Adenomera clade. We provide a redescription of A. marmorata and restrict its type locality to the Tijuca Massif, in the Municipality of Rio de Janeiro, Brazil. Our results do not support A. marmorata and the two candidate species as diagnosable distinct species. Therefore A. marmorata corresponds to a species with pronounced morphological and acoustic variation in the genus and a complex phylogeographic structure.


Subject(s)
Acoustics , Anura/anatomy & histology , Anura/classification , Conservation of Natural Resources , Phylogeny , Phylogeography , Animal Distribution , Animals , Anura/genetics , Brazil , Species Specificity
16.
Adv Mater ; 32(1): e1903878, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31686433

ABSTRACT

Chirality is ubiquitous in nature and hard-wired into every biological system. Despite the prevalence of chirality in biological systems, controlling biomaterial chirality to influence interactions with cells has only recently been explored. Chiral-engineered supraparticles (SPs) that interact differentially with cells and proteins depending on their handedness are presented. SPs coordinated with d-chirality demonstrate greater than threefold enhanced cell membrane penetration in breast, cervical, and multiple myeloma cancer cells. Quartz crystal microbalance with dissipation and isothermal titration calorimetry measurements reveal the mechanism of these chiral-specific interactions. Thermodynamically, d-SPs show more stable adhesion to lipid layers composed of phospholipids and cholesterol compared to l-SPs. In vivo, d-SPs exhibit superior stability and longer biological half-lives likely due to opposite chirality and thus protection from endogenous proteins including proteases. This work shows that incorporating d-chirality into nanosystems enhances uptake by cancer cells and prolonged in vivo stability in circulation, providing support for the importance of chirality in biomaterials. Thus, chiral nanosystems may have the potential to provide a new level of control for drug delivery systems, tumor detection markers, biosensors, and other biomaterial-based devices.


Subject(s)
Biocompatible Materials/chemistry , Nanomedicine , Biocompatible Materials/pharmacology , Biosensing Techniques/methods , Cell Line , Cell Survival/drug effects , Cysteine/chemistry , Half-Life , Humans , Lipid Bilayers/metabolism , Lipids/chemistry , Microscopy, Confocal , Polyethylene Glycols/chemistry , Quartz Crystal Microbalance Techniques , Stereoisomerism , Thermodynamics
17.
J Control Release ; 316: 404-417, 2019 12 28.
Article in English | MEDLINE | ID: mdl-31678653

ABSTRACT

Messenger RNA (mRNA) has recently emerged as a promising class of nucleic acid therapy, with the potential to induce protein production to treat and prevent a range of diseases. However, the widespread use of mRNA as a therapeutic requires safe and effective in vivo delivery technologies. Libraries of ionizable lipid nanoparticles (LNPs) have been designed to encapsulate mRNA, prevent its degradation, and mediate intracellular delivery. However, these LNPs are typically characterized and screened in an in vitro setting, which may not fully replicate the biological barriers that they encounter in vivo. Here, we designed and evaluated a library of engineered LNPs containing barcoded mRNA (b-mRNA) to accelerate the screening of mRNA delivery platforms in vivo. These b-mRNA are similar in structure and function to regular mRNA, and contain barcodes that enable their delivery to be quantified via deep sequencing. Using a mini-library of b-mRNA LNPs formulated via microfluidic mixing, we show that these different formulations can be pooled together, administered intravenously into mice as a single pool, and their delivery to multiple organs (liver, spleen, brain, lung, heart, kidney, pancreas, and muscle) can be quantified simultaneously using deep sequencing. In the context of liver and spleen delivery, LNPs that exhibited high b-mRNA delivery also yielded high luciferase expression, indicating that this platform can identify lead LNP candidates as well as optimal formulation parameters for in vivo mRNA delivery. Interestingly, LNPs with identical formulation parameters that encapsulated different types of nucleic acid barcodes (b-mRNA versus a DNA barcode) altered in vivo delivery, suggesting that the structure of the barcoded nucleic acid affects LNP in vivo delivery. This platform, which enables direct barcoding and subsequent quantification of a functional mRNA, can accelerate the in vivo screening and design of LNPs for mRNA therapeutic applications such as CRISPR-Cas9 gene editing, mRNA vaccination, and other mRNA-based regenerative medicine and protein replacement therapies.


Subject(s)
Gene Transfer Techniques , Lipids/chemistry , Nanoparticles , RNA, Messenger/administration & dosage , Animals , Electronic Data Processing , Female , Genetic Therapy , Mice , Mice, Inbred C57BL , Microfluidics
18.
Zootaxa ; 4706(4): zootaxa.4706.4.3, 2019 Dec 11.
Article in English | MEDLINE | ID: mdl-32230519

ABSTRACT

We describe a new species of Ischnocnema from the Serra da Bocaina mountain range, state of São Paulo, southeastern Brazil, based on morphological, bioacoustic, and mtDNA data. The new species is retrieved with high support values within the I. lactea species series as the sister species of I. spanios. Ischnocnema bocaina sp. nov. is characterized by its medium size (18.6-19.0 mm), a smooth venter, a rounded snout in dorsal view and acuminate in lateral view, a slightly expanded subgular, single vocal sac, a round and whitish, poorly-developed glandular-appearing nuptial pad on the dorsal surface of the thumb, and a nonpulsed advertisement call with 9 to 18 notes. We raise to 38 the number of Ischnocnema species, the 12th described in the past 10 years.


Subject(s)
Anura , DNA, Mitochondrial , Animals , Brazil
19.
J Control Release ; 290: 75-87, 2018 11 28.
Article in English | MEDLINE | ID: mdl-30290244

ABSTRACT

Activation of the Wnt signaling pathway promotes lung cancer progression and contributes to poor patient prognosis. The porcupine inhibitor LGK974, a novel orally bioavailable cancer therapeutic in Phase I clinical trials, induces potent Wnt signaling inhibition and leads to suppressed growth and progression of multiple types of cancers. The clinical use of LGK974, however, is limited in part due to its low solubility and high toxicity in tissues that rely on Wnt signaling for normal homeostasis. Here, we report the use of host-guest chemistry to enhance the solubility and bioavailability of LGK974 in mice through complexation with cyclodextrins (CD). We assessed the effects of these complexes to inhibit Wnt signaling in lung adenocarcinomas that are typically driven by overactive Wnt signaling. 2D 1H NMR confirmed host-guest complexation of CDs with LGK974. CD:LGK974 complexes significantly decreased the expression of Wnt target genes in lung cancer organoids and in lung cancer allografts in mice. Further, CD:LGK974 complexes increased the bioavailability upon oral administration in mice compared to free LGK974. In a mouse lung cancer allograft model, CD:LGK974 complexes induced potent Wnt signaling inhibition with reduced intestinal toxicity compared to treatment with free drug. Collectively, the development of these complexes enables safer and repeated oral or parenteral administration of Wnt signaling inhibitors, which hold promise for the treatment of multiple types of malignancies.


Subject(s)
Adenocarcinoma of Lung/drug therapy , Antineoplastic Agents/administration & dosage , Cyclodextrins/administration & dosage , Lung Neoplasms/drug therapy , Pyrazines/administration & dosage , Pyridines/administration & dosage , Wnt Proteins/antagonists & inhibitors , Wnt Signaling Pathway/drug effects , Adenocarcinoma of Lung/metabolism , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacokinetics , Cell Line, Tumor , Cyclodextrins/chemistry , Cyclodextrins/pharmacokinetics , Humans , Lung Neoplasms/metabolism , Mice, Nude , Pyrazines/chemistry , Pyrazines/pharmacokinetics , Pyridines/chemistry , Pyridines/pharmacokinetics
20.
Mol Phylogenet Evol ; 128: 123-146, 2018 11.
Article in English | MEDLINE | ID: mdl-30146039

ABSTRACT

We present a new phylogenetic hypothesis for Ischnocnema, a Neotropical brachycephaloid genus of ground-dwelling direct-developing frogs. We performed Bayesian inference, maximum likelihood, and maximum parsimony analyses using two nuclear (RAG1 and Tyr) and three mitochondrial genes (12S rRNA, tRNA-Val, and 16S rRNA) in a matrix comprising more than 80% of the described species. We recover Ischnocnema nanahallux outside the Ischnocnema parva series, and it is now unassigned to any species series, nor are Ischnocnema manezinho and Ischnocnema sambaqui. We propose the Ischnocnema venancioi species series to comprise Ischnocnema venancioi, Ischnocnema hoehnei, and two new species described herein (Ischnocnema parnaso sp. nov. and Ischnocnema colibri sp. nov.). Furthermore, we designate a lectotype for I. venancioi. The nuptial pad present in males is an important character in the genus, and having a large, conspicuous, and glandular-appearing nuptial pad seems to be a synapomorphy for the clade composed of the I. parva, Ischnocnema guentheri, and the newly proposed I. venancioi series.


Subject(s)
Anura/classification , Phylogeny , Acoustics , Animals , Anura/anatomy & histology , Anura/genetics , Bayes Theorem , Calibration , Genetic Variation , Geography , Models, Genetic , Species Specificity , Territoriality , Time Factors , Vocalization, Animal
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