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CD4+ T cells are central mediators of adaptive and innate immune responses and constitute a major reservoir for human immunodeficiency virus (HIV) in vivo. Detailed investigations of resting human CD4+ T cells have been precluded by the absence of efficient approaches for genetic manipulation limiting our understanding of HIV replication and restricting efforts to find a cure. Here we report a method for rapid, efficient, activation-neutral gene editing of resting, polyclonal human CD4+ T cells using optimized cell cultivation and nucleofection conditions of Cas9-guide RNA ribonucleoprotein complexes. Up to six genes, including HIV dependency and restriction factors, were knocked out individually or simultaneously and functionally characterized. Moreover, we demonstrate the knock in of double-stranded DNA donor templates into different endogenous loci, enabling the study of the physiological interplay of cellular and viral components at single-cell resolution. Together, this technique allows improved molecular and functional characterizations of HIV biology and general immune functions in resting CD4+ T cells.
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Linfócitos T CD4-Positivos/fisiologia , Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Infecções por HIV/genética , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/virologia , Proteína 9 Associada à CRISPR/genética , Movimento Celular/genética , Células Cultivadas , DNA , Técnicas de Inativação de Genes , Infecções por HIV/metabolismo , Humanos , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Proteínas de Resistência a Myxovirus/genética , Proteínas de Resistência a Myxovirus/metabolismo , RNA Guia de Cinetoplastídeos , Proteína 1 com Domínio SAM e Domínio HD/genética , Transgenes , Fatores de Poliadenilação e Clivagem de mRNA/genética , Fatores de Poliadenilação e Clivagem de mRNA/metabolismoRESUMO
Vaccines of outstanding efficiency, safety, and public acceptance are needed to halt the current SARS-CoV-2 pandemic. Concerns include potential side effects caused by the antigen itself and safety of viral DNA and RNA delivery vectors. The large SARS-CoV-2 spike (S) protein is the main target of current COVID-19 vaccine candidates but can induce non-neutralizing antibodies, which might cause vaccination-induced complications or enhancement of COVID-19 disease. Besides, encoding of a functional S in replication-competent virus vector vaccines may result in the emergence of viruses with altered or expanded tropism. Here, we have developed a safe single round rhabdovirus replicon vaccine platform for enhanced presentation of the S receptor-binding domain (RBD). Structure-guided design was employed to build a chimeric minispike comprising the globular RBD linked to a transmembrane stem-anchor sequence derived from rabies virus (RABV) glycoprotein (G). Vesicular stomatitis virus (VSV) and RABV replicons encoding the minispike not only allowed expression of the antigen at the cell surface but also incorporation into the envelope of secreted non-infectious particles, thus combining classic vector-driven antigen expression and particulate virus-like particle (VLP) presentation. A single dose of a prototype replicon vaccine complemented with VSV G, VSVΔG-minispike-eGFP (G), stimulated high titers of SARS-CoV-2 neutralizing antibodies in mice, equivalent to those found in COVID-19 patients, and protected transgenic K18-hACE2 mice from COVID-19-like disease. Homologous boost immunization further enhanced virus neutralizing activity. The results demonstrate that non-spreading rhabdovirus RNA replicons expressing minispike proteins represent effective and safe alternatives to vaccination approaches using replication-competent viruses and/or the entire S antigen.
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Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Vacinas contra COVID-19/administração & dosagem , COVID-19/prevenção & controle , Imunização/métodos , SARS-CoV-2/imunologia , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/virologia , Feminino , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BLRESUMO
The Internet of Things (IoT) concept involves connecting devices to the internet and forming a network of objects that can collect information from the environment without human intervention. Although the IoT concept offers some advantages, it also has some issues that are associated with cyber security risks, such as the lack of detection of malicious wireless sensor network (WSN) nodes, lack of fault tolerance, weak authorization, and authentication of nodes, and the insecure management of received data from IoT devices. Considering the cybersecurity issues of IoT devices, there is an urgent need of finding new solutions that can increase the security level of WSNs. One issue that needs attention is the secure management and data storage for IoT devices. Most of the current solutions are based on systems that operate in a centralized manner, ecosystems that are easy to tamper with and provide no records regarding the traceability of the data collected from the sensors. In this paper, we propose an architecture based on blockchain technology for securing and managing data collected from IoT devices. By implementing blockchain technology, we provide a distributed data storage architecture, thus eliminating the need for a centralized network topology using blockchain advantages such as immutability, decentralization, distributivity, enhanced security, transparency, instant traceability, and increased efficiency through automation. From the obtained results, the proposed architecture ensures a high level of performance and can be used as a scalable, massive data storage solution for IoT devices using blockchain technologies. New WSN communication protocols can be easily enrolled in our data storage blockchain architecture without the need for retrofitting, as our system does not depend on any specific communication protocol and can be applied to any IoT application.
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Currently, for seemingly every type of cancer, dysregulated levels of non-coding RNAs (ncRNAs) are reported and non-coding transcripts are expected to be the next class of diagnostic and therapeutic tools in oncology. Recently, alterations to the ncRNAs transcriptome have emerged as a novel hallmark of cancer. Historically, ncRNAs were characterized mainly as regulators and little attention was paid to the mechanisms that regulate them. The role of modifications, which can control the function of ncRNAs post-transcriptionally, only recently began to emerge. Typically, these modifications can be divided into reversible (i.e., chemical modifications: m5C, hm5C, m6A, m1A, and pseudouridine) and non-reversible (i.e., editing: ADAR dependent, APOBEC dependent and ADAR/APOBEC independent). The first research papers showed that levels of these modifications are altered in cancer and can be part of the tumorigenic process. Hence, the aim of this review paper is to describe the most common regulatory modifications (editing and chemical modifications) of the traditionally considered "non-functional" ncRNAs (i.e., microRNAs, long non-coding RNAs and circular RNAs) in the context of malignant disease. We consider that only by understanding this extra regulatory layer is it possible to translate the knowledge about ncRNAs and their modifications into clinical practice.
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Neoplasias/genética , Edição de RNA/genética , RNA não Traduzido/genética , Transcriptoma/genética , Carcinogênese/genética , Humanos , Neoplasias/terapia , RNA não Traduzido/uso terapêuticoRESUMO
BACKGROUND: Central pancreatectomy (CP) is the alternative to distal pancreatectomy (DP) for specific pathologies of the mid-pancreas. However, the benefits of CP over DP remain controversial. This study aims to compare the two procedures by conducting a meta-analysis of all published papers. METHODS: A systematic search of original studies comparing CP vs. DP was performed using PubMed, Scopus, and Cochrane Library databases up to June 2018. The Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) checklist was followed. RESULTS: Twenty-one studies were included (596 patients with CP and 1070 patients with DP). Compared to DP, CP was associated with significantly higher rates of overall and severe morbidity (p < 0.0001), overall and clinically relevant pancreatic fistula (p < 0.0001), postoperative hemorrhage (p = 0.02), but with significantly lower incidences of new-onset (p < 0.0001) and worsening diabetes mellitus (p = 0.004). Furthermore, significantly longer length of hospital stay (p < 0.0001) was observed for CP patients. CONCLUSIONS: CP is superior to DP regarding the preservation of pancreatic functions, but at the expense of significantly higher complication rates and longer hospital stay. Proper selection of patients is of utmost importance to maximize the benefits and mitigate the risks of CP.
Assuntos
Laparoscopia/métodos , Técnicas de Abdome Aberto/métodos , Pâncreas/cirurgia , Pancreatectomia/métodos , Neoplasias Pancreáticas/cirurgia , Intervalo Livre de Doença , Feminino , Humanos , Laparoscopia/efeitos adversos , Tempo de Internação , Masculino , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Técnicas de Abdome Aberto/efeitos adversos , Duração da Cirurgia , Pâncreas/anatomia & histologia , Pancreatectomia/mortalidade , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Seleção de Pacientes , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/fisiopatologia , Prognóstico , Medição de Risco , Análise de SobrevidaRESUMO
The ρ(770) meson is the most extensively studied resonance in lattice QCD simulations in two (N_{f}=2) and three (N_{f}=2+1) flavor formulations. We analyze N_{f}=2 lattice scattering data using unitarized chiral perturbation theory, allowing not only for the extrapolation in mass but also in flavor, N_{f}=2âN_{f}=2+1. The flavor extrapolation requires information from a global fit to ππ and πK phase shifts from experiment. While the chiral extrapolation of N_{f}=2 lattice data leads to masses of the ρ(770) meson far below the experimental one, we find that the missing KK[over ¯] channel is able to explain this discrepancy.
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Understanding the surface properties of particles is crucial for optimizing the performance of formulated products in various industries. However, acquiring this understanding often requires expensive trial-and-error studies. Here, we present advanced surface analysis tools that enable the visualization and quantification of chemical and topological information derived from crystallographic data. By employing functional group analysis, roughness calculations, and statistical interaction data, we facilitate direct comparisons of surfaces. We further demonstrate the practicality of our approach by correlating the sticking propensity of distinct ibuprofen morphologies with surface and particle descriptors calculated from a single crystal structure. Our findings support and expand upon previous work, demonstrating that the presence of a carboxylic acid group on the {011} facet leads to significant differences in particle properties and explains the higher electrostatic potential observed in the block-like morphology. While our surface analysis tools are not intended to replace the importance of chemical intuition and expertise, they provide valuable insights for formulators and particle engineers, facilitating informed, data-driven decisions to mitigate formulation risks. This research represents a significant step toward a comprehensive understanding of particle surfaces and their impact on products.
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BACKGROUND: Microcalorimetric bacterial growth studies have illustrated that thermograms differ significantly with both culture media and strain. The present contribution examines the possibility of discriminating between certain bacterial strains by microcalorimetry and the qualitative and quantitative contribution of the sample volume to the observed thermograms. Growth patterns of samples of Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922) were analyzed. Certain features of the thermograms that may serve to distinguish between these bacterial strains were identified. RESULTS: The thermograms of the two bacterial strains with sample volumes ranging from 0.3 to 0.7 ml and same initial bacterial concentration were analyzed. Both strains exhibit a roughly 2-peak shape that differs by peak amplitude and position along the time scale. Seven parameters corresponding to the thermogram key points related to time and heat flow values were proposed and statistically analyzed. The most relevant parameters appear to be the time to reach a heat flow of 0.05 mW (1.67 ± 0.46 h in E. coli vs. 2.99 ± 0.53 h in S. aureus, p < 0.0001), the time to reach the first peak (3.84 ± 0.5 h vs. 5.17 ± 0.49 h, p < 0.0001) and the first peak value (0.19 ± 0.02 mW vs. 0.086 ± 0.012 mW, p < 0.0001). The statistical analysis on 4 parameters of volume-normalized heat flow thermograms showed that the time to reach a volume-normalized heat flow of 0.1 mW/ml (1.75 ± 0.37 h in E. coli vs. 2.87 ± 0.65 h in S. aureus, p < 0.005), the time to reach the first volume-normalized peak (3.78 ± 0.47 h vs. 5.12 ± 0.52 h, p < 0.0001) and the first volume-normalized peak value (0.35 ± 0.05 mW/ml vs. 0.181 ± 0.040 mW/ml, p < 0.0001) seem to be the most relevant. Peakfit® decomposition and analysis of the observed thermograms complements the statistical analysis via quantitative arguments, indicating that: (1) the first peak pertains to a faster, "dissolved oxygen" bacterial growth (where the dissolved oxygen in the initial suspension acts as a limiting factor); (2) the second peak indicates a slower "diffused oxygen" growth that involves transport of oxygen contained in the unfilled part of the microcalorimetric cell; (3) a strictly fermentative growth component may slightly contribute to the observed complex thermal signal. CONCLUSION: The investigated strains of Staphylococcus aureus and Escherichia coli display, under similar experimental conditions, distinct thermal growth patterns. The two strains can be easily differentiated using a selection of the proposed parameters. The presented Peakfit analysis of the complex thermal signal provides the necessary means for establishing the optimal growth conditions of various bacterial strains. These conditions are needed for the standardization of the isothermal microcalorimetry method in view of its further use in qualitative and quantitative estimation of bacterial growth.
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Calorimetria/métodos , Escherichia coli/crescimento & desenvolvimento , Staphylococcus aureus/crescimento & desenvolvimento , Técnicas Bacteriológicas/métodos , Especificidade da EspécieRESUMO
Intermolecular (synthonic) modelling is used for a statistical analysis of crystal lattice energies, together with their contributing intermolecular interactions for the crystallographic structures selected from the CCDC's Drug Subset (https://doi.org/10.1016/j.xphs.2018.12.011). Analysis of this selected subset reveal similarities in packing compared to other organic crystals in the CSD with linear relationships between molecular weight and unit cell volume, void space, and packing coefficient. Crystal lattice energy calculations converge within a 30 Å intermolecular radius characterised by a mean lattice energy of ca. -36 kcal mol-1 with ca. 85% and 15% due to dispersive and electrostatic interactions, respectively. The distribution of the strongest synthons within the individual structures reveals an average strength of -5.79 kcal mol-1. The diversity of chemical space within the drug molecules is in agreement with the analysis of atom types across the selected subset with phenyl groups being found to contribute the highest mean energy of -11.28 kcal mol-1, highlighting the importance of aromatic interactions within pharmaceutical compounds. Despite an initial focus on Z'â¯=â¯1 structures, this automated approach enables rapid and consistent quantitative analysis of lattice energy, synthon strength and functional group contributions, providing solid-form informatics for pharmaceutical R&D and a helpful basis for further investigations.
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Fenômenos Físicos , Cristalografia , Preparações FarmacêuticasRESUMO
PURPOSE: The impact of adjuvant chemotherapy (CT) in the management of radically resected stage IB non-small cell lung cancer (NSCLC) is highly debated. The aim of this study was to evaluate the outcome of this category of patients treated at our institution. METHODS: We retrospectively analysed the survival data of patients with pathologic stage IB NSCLC, who received at least 1 cycle of adjuvant CT. CT was planned to be platinum based and to be delivered for 6 cycles. RESULTS: One hundred and twelve consecutively treated patients were evaluated. PATIENT CHARACTERISTICS: median age 60 years, median tumor diameter 4 cm, 87% underwent lobectomy and 13% pneumonectomy, 58% had visceral pleural involvement (VPI). After a median follow up of 46 months, the estimated 5-year disease-free (DFS) and overall survival (OS) rates were 68% and 77%, respectively. The mean number of CT cycles was 5.2 (range 3-6), with 82% of patients receiving ≥ 5 cycles. The median cisplatin dose intensity (DI) was 22 mg/m(2)/week, and the relative DI was 85%. Median total cisplatin (CDDP) dose/patient was 416 mg/m(2). A total of 31 (27.6%) relapses were recorded, of which 81% were distant. Multivariate analysis showed no significant interaction between overall survival and the following variables: gender, type of surgery, histology, tumor volume, VPI. CONCLUSION: Our results compare favorably with the historical data evaluating the outcome of stage IB patients treated by surgery alone in a customary medical setting. Overall, our data support the use of adjuvant CT in stage IB NSCLC patients.
Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Carcinoma de Células Grandes/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma de Células Escamosas/tratamento farmacológico , Cisplatino/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Adenocarcinoma/mortalidade , Adulto , Idoso , Carcinoma de Células Grandes/mortalidade , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma de Células Escamosas/mortalidade , Quimioterapia Adjuvante , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia/mortalidade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
Photorhabdus luminescens is a pathogenic bacterium that produces many toxic proteins. The mono-ADP-ribosyltransferases (mARTs) are an enzyme class produced by numerous pathogenic bacteria and participate in disease in plants and animals, including humans. Herein we report a novel mART from P. luminescens called Photox. This 46-kDa toxin shows high homology to other actin-targeting mARTs in hallmark catalytic regions and a similar core catalytic fold. Furthermore, Photox shows in vivo cytotoxic activity against yeast, with protection occurring when catalytic residues are substituted with alanine. In vitro, enzymatic activity (k(cat), 1680 +/- 75 min(-1)) is higher than that of the related iota toxin, and diminishes by nearly 14,000-fold following substitution of the catalytic Glu (E355A). This toxin specifically ADP-ribosylates monomeric alpha-skeletal actin and nonmuscle beta- and gamma-actin at Arg(177), inhibiting regular polymerization of actin filaments. These results indicate that Photox is indeed an ADP-ribosyltransferase, making it the newest member of the actin-targeting mART family.
Assuntos
ADP Ribose Transferases/metabolismo , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Toxinas Bacterianas/metabolismo , Photorhabdus/enzimologia , ADP Ribose Transferases/química , ADP Ribose Transferases/genética , Citoesqueleto de Actina/química , Citoesqueleto de Actina/genética , Actinas/química , Actinas/genética , Animais , Toxinas Bacterianas/química , Toxinas Bacterianas/genética , Galinhas , Photorhabdus/genética , Photorhabdus/patogenicidade , Doenças das Plantas/microbiologiaRESUMO
Biomolecules readily and irreversibly bind to plasma deposited Polyoxazoline thin films in physiological conditions. The unique reactivity of these thin films toward antibodies is driving the development of immunosensing platforms for applications in cancer diagnostics. However, in order for these coatings to be used as advanced immunosensors, they need to be incorporated into microfluidic devices that are sealed via plasma bonding. In this work, the thickness, chemistry and reactivity of the polyoxazoline films were assessed following plasma activation. Films deposited from methyl and isopropenyl oxazoline precursors were integrated into spiral microfluidic devices and biofunctionalized with prostate cancer specific antibodies. Using microbeads as model particles, the design of the spiral microfluidic was optimised to enable the size-based isolation of cancer cells. The device was tested with a mixed cell suspension of healthy and malignant prostate cells. The results showed that, following size-specific separation in the spiral, selective capture was achieved on the immunofunctionalised PPOx surface. This proof of concept study demonstrates that plasma deposited polyoxazoline can be used for immunosensing in plasma bonded microfluidic devices.
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Cancer is a devastating disease and has recently become the leading cause of death in western countries, representing an immense public health burden. When it comes to cancer treatment, chemotherapy is one of the main pillars, especially for advanced stage tumors. Over the years, natural compounds have emerged as one of the most valuable resources for new chemotherapies. It is estimated that more than half of the currently used chemotherapeutic agents are derived from natural compounds. Usually, natural compounds are discovered empirically and an important limitation of introducing new anti-cancer natural products is lack of knowledge with regard to their mechanism of action. Recent data has proven that several natural compounds may function via modulating the expression and function of non-coding RNAs (ncRNAs). NcRNAs are a heterogenous class of RNA molecules which are usually not translated into proteins but have an important role in gene expression regulation and are involved in multiple tumorigenic processes, including response/resistance to pharmacotherapy. In this review, we will discuss how natural compounds function via ncRNAs while summarizing the available data regarding their effects on over 15 types of cancer. Moreover, we will critically analyze the current advances and limitations in understanding the way natural compounds exert these health-promoting effects by acting on ncRNAs. Finally, we will propose several hypotheses that may open new avenues and perspectives regarding the interaction between natural compounds and ncRNAs, which could lead to improved natural compound-based therapeutic strategies in cancer.
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BACKGROUND: To further characterize survival benefit with first-line nivolumab plus ipilimumab with two cycles of chemotherapy versus chemotherapy alone, we report updated data from the phase III CheckMate 9LA trial with a 2-year minimum follow-up. PATIENTS AND METHODS: Adult patients were treatment naïve, with stage IV/recurrent non-small-cell lung cancer, no known sensitizing EGFR/ALK alterations, and an Eastern Cooperative Oncology Group performance status ≤1. Patients were randomized 1 : 1 to nivolumab 360 mg every 3 weeks plus ipilimumab 1 mg/kg every 6 weeks with two cycles of chemotherapy, or four cycles of chemotherapy. Updated efficacy and safety outcomes are reported, along with progression-free survival (PFS) after next line of treatment (PFS2), treatment-related adverse events (TRAEs) by treatment cycle, and efficacy outcomes in patients who discontinued all treatment components in the experimental arm due to TRAEs. RESULTS: With a median follow-up of 30.7 months, nivolumab plus ipilimumab with chemotherapy continued to prolong overall survival (OS) versus chemotherapy. Median OS was 15.8 versus 11.0 months [hazard ratio 0.72 (95% confidence interval 0.61-0.86)]; 2-year OS rate was 38% versus 26%. Two-year PFS rate was 20% versus 8%. ORR was 38% versus 25%, respectively; 34% versus 12% of all responses were ongoing at 2 years. Median PFS2 was 13.9 versus 8.7 months. Improved efficacy outcomes in the experimental versus control arm were observed across most subgroups, including by programmed death-ligand 1 and histology. No new safety signals were observed; onset of grade 3/4 TRAEs was mostly observed during the first two treatment cycles in the experimental arm. In patients who discontinued all components of nivolumab plus ipilimumab with chemotherapy treatment due to TRAEs (n = 61) median OS was 27.5 months; 56% of responders had an ongoing response ≥1 year after discontinuation. CONCLUSIONS: With a 2-year minimum follow-up, nivolumab plus ipilimumab with two cycles of chemotherapy provided durable efficacy benefits over chemotherapy with a manageable safety profile and remains an efficacious first-line treatment of advanced non-small-cell lung cancer.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Ipilimumab/efeitos adversos , Neoplasias Pulmonares/tratamento farmacológico , Recidiva Local de Neoplasia , Nivolumabe/efeitos adversosRESUMO
The lateral hypothalamus (LH) is critically involved in the regulation of homeostatic energy balance. Some neurons in the LH express receptors for leptin (LepRb), a hormone known to increase energy expenditure and decrease energy intake. However, the neuroanatomical inputs to LepRb-expressing LH neurons remain unknown. We used rabies virus tracing technology to map these inputs, but encountered non-specific tracing. To optimize this technology for a minor cell population (LepRb is not ubiquitously expressed in LH), we used LepRb-Cre mice and assessed how different titers of the avian tumor virus receptor A (TVA) helper virus affected rabies tracing efficiency and specificity. We found that rabies expression is dependent on TVA receptor expression, and that leakiness of TVA receptors is dependent on the titer of TVA virus used. We concluded that a titer of 1.0-3.0 × 107 genomic copies per µl of the TVA virus is optimal for rabies tracing. Next, we successfully applied modified rabies virus tracing technology to map inputs to LepRb-expressing LH neurons. We discovered that other neurons in the LH itself, the periventricular hypothalamic nucleus (Pe), the posterior hypothalamic nucleus (PH), the bed nucleus of the stria terminalis (BNST), and the paraventricular hypothalamic nucleus (PVN) are the most prominent input areas to LepRb-expressing LH neurons.
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Conectoma/métodos , Hipotálamo/diagnóstico por imagem , Imagem Molecular/métodos , Neurônios/metabolismo , Receptores para Leptina/análise , Animais , Proteínas Aviárias/genética , Feminino , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Vírus Auxiliares/genética , Hipotálamo/citologia , Hipotálamo/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Microscopia de Fluorescência , Vírus da Raiva/genética , Receptores para Leptina/metabolismo , Receptores Virais/genética , Núcleos Septais/citologia , Núcleos Septais/diagnóstico por imagem , Núcleos Septais/metabolismo , Técnicas EstereotáxicasRESUMO
Actin filament subunit interfaces are required for the proper interaction between filamentous actin (F-actin) and actin binding proteins (ABPs). The production of small F-actin complexes mimicking such interfaces would be a significant advance toward understanding the atomic interactions between F-actin and its many binding partners. We produced actin lateral dimers and trimers derived from F-actin and rendered polymerization-deficient by ADP-ribosylation of Arg-177. The degree of modification resulted in a moderate reduction in thermal stability. Calculated hydrodynamic radii were comparable to theoretical values derived from recent models of F-actin. Filament capping capabilities were retained and yielded pointed-end dissociation constants similar those of wild-type actin, suggesting native or near-native interfaces on the oligomers. Changes in DNase I binding affinity under low and high ionic strength suggested a high degree of conformational flexibility in the dimer and trimer. Polymer nucleation activity was lost upon ADP-ribosylation and rescued upon enzyme-mediated deADP-ribosylation, or upon binding to gelsolin, suggesting that interactions with actin binding proteins can overcome the inhibiting activities of ADP-ribosylation. The combined strategy of chemical cross-linking and ADP-ribosylation provides a minimalistic and reversible approach to engineering polymerization-deficient F-actin oligomers that are able to act as F-actin binding protein scaffolds.
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Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Adenosina Difosfato Ribose/metabolismo , Multimerização Proteica/fisiologia , Citoesqueleto de Actina/química , Actinas/química , Adenosina Difosfato Ribose/química , Animais , Bovinos , Galinhas , Desoxirribonuclease I/química , Desoxirribonuclease I/metabolismo , Gelsolina/química , Gelsolina/metabolismo , Humanos , Ligação Proteica , Estrutura Quaternária de ProteínaRESUMO
BACKGROUND: A microcalorimetric study was carried out using a Staphylococcus epidermidis population to determine the reproducibility of bacterial growth and the variability of the results within certain experimental parameters (temperature, bacterial concentration, sample thermal history). Reproducibility tests were performed as series of experiments within the same conditions using either freshly prepared populations or samples kept in cold storage. In both cases, the samples were obtained by serial dilution from a concentrated TSB bacterial inoculum incubated overnight. RESULTS: The results show that experiments are fairly reproducible and that specimens can be preserved at low temperatures (1 - 2°C) at least 4 days. The thermal signal variations at different temperatures and initial bacterial concentrations obey a set of rules that we identified. CONCLUSION: Our study adds to the accumulating data and confirms available results of isothermal microcalorimetry applications in microbiology and can be used to standardize this method for either research or clinical setting.
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Calorimetria/métodos , Staphylococcus epidermidis/química , Staphylococcus epidermidis/crescimento & desenvolvimento , Viabilidade MicrobianaRESUMO
Cutaneous melanoma is the most aggressive skin malignancies with increasing rate of incidence in the latest decades. New imaging technique plays an important role in melanoma management: dermoscopy and computer dermoscopy, ultrasound, MRI, CT, PET and PET/CT. Due to the dermoscopy and lesion diagnosis in early stages the increasing number of curative melanoma are registered. Sentinel lymph node biopsy became a compulsory phase for patients with tumor thickness > 1 mm. Serological biomarkers proved to be a necessary investigation for melanoma diagnosis, follow-up and treatment response. Current TNM melanoma staging is based on AJCC classification since 2001 witch includes new elements like histopathologic ulceration in stage I and II and lymph node micro- and macrometastases in stage III. Treatment protocols include surgical tumor excision with only 1-2 cm safety margins and radical lymphadenectomy is performed after positive sentinel lymph node biopsy. The adjuvant treatment in advanced stages including chemotherapy, unspecific immunotherapy and interferon offers poor results regarding free disease terms rate of survival. The advanced therapeutic procedure like golden nanospheres and gene therapy are recently studied and represent an alternative for future treatment of melanoma. Follow-up protocols have a great importance for detection of the melanoma recurrences and include clinical, serological and imaging evaluation. Despite all new knowledge and technological support the advanced stage melanoma management still remain an unsolved problem.
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Melanoma/diagnóstico , Melanoma/terapia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/terapia , Quimioterapia Adjuvante , Diagnóstico Diferencial , Detecção Precoce de Câncer , Humanos , Incidência , Oncologia/tendências , Melanoma/mortalidade , Estadiamento de Neoplasias , Fatores de Risco , Romênia/epidemiologia , Biópsia de Linfonodo Sentinela , Taxa de Sobrevida , Resultado do TratamentoRESUMO
Rhabdoviruses, as single-stranded, negative-sense RNA viruses within the order Mononegavirales, are characterised by bullet-shaped or bacteroid particles that contain a helical ribonucleoprotein complex (RNP). Here, we review the components of the RNP and its higher-order structural assembly.
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Rhabdoviridae/química , Ribonucleoproteínas/química , Proteínas Virais/química , Proteínas do Nucleocapsídeo/química , Proteínas do Nucleocapsídeo/ultraestrutura , Conformação Proteica , Rhabdoviridae/genética , Ribonucleoproteínas/ultraestrutura , Proteínas da Matriz Viral/química , Proteínas da Matriz Viral/ultraestrutura , Proteínas Virais/ultraestrutura , Proteínas do Complexo da Replicase Viral/química , Proteínas do Complexo da Replicase Viral/ultraestrutura , Vírion/químicaRESUMO
The insular cortex (IC) plays key roles in emotional and regulatory brain functions and is affected across psychiatric diseases. However, the brain-wide connections of the mouse IC have not been comprehensively mapped. Here, we traced the whole-brain inputs and outputs of the mouse IC across its rostro-caudal extent. We employed cell-type-specific monosynaptic rabies virus tracings to characterize afferent connections onto either excitatory or inhibitory IC neurons, and adeno-associated viral tracings to label excitatory efferent axons. While the connectivity between the IC and other cortical regions was highly bidirectional, the IC connectivity with subcortical structures was often unidirectional, revealing prominent cortical-to-subcortical or subcortical-to-cortical pathways. The posterior and medial IC exhibited resembling connectivity patterns, while the anterior IC connectivity was distinct, suggesting two major functional compartments. Our results provide insights into the anatomical architecture of the mouse IC and thus a structural basis to guide investigations into its complex functions.