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1.
Mod Rheumatol ; 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38753302

RESUMEN

OBJECTIVES: This systematic review assessed the efficacy and safety of abatacept in patients with systemic juvenile idiopathic arthritis (JIA). METHODS: Studies published between 2000 and 2021 were searched using PubMed, Embase, Cochrane, Ichushi-Web and clinical trial registries. The risk of bias was assessed according to the manual for development clinical practice guidelines by Minds, a project to promote evidence-based medicine in Japan. RESULTS: Seven observational studies were included. American College of Rheumatology pediatric 30/50/70 responses at 3, 6 and 12 months were 64.8%/50.3%/27.9%, 85.7%/71.4%/42.9% and 80.0%/50.0%/40.0%, respectively. Outcomes on systemic symptoms, joint symptoms and activities of daily living were not obtained. No macrophage activation syndrome or infusion reaction occurred. Serious infection occurred in 2.6% of cases. CONCLUSIONS: Abatacept improved the disease activity index. In addition, abatacept was as safe as interleukin-6 (IL -6) and IL-1 inhibitors. However, both the efficacy and safety data in this systematic review should be reviewed with caution because their quality of evidence is low or very low. Further studies are needed to confirm the efficacy and safety of abatacept for systemic JIA, especially its efficacy on joint symptoms.

2.
Mod Rheumatol ; 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38795057

RESUMEN

OBJECTIVES: This systematic review assessed the efficacy and safety of tumor necrosis factor (TNF) inhibitors in patients with systemic juvenile idiopathic arthritis (JIA). METHODS: Studies were searched using PubMed, Embase, Cochrane, Ichushi-Web, and clinical trial registries (from 2000 to 2021). The risk of bias was assessed using the Cochrane Risk of Bias version 2 for randomized controlled trials (RCTs) and the manual for development clinical practice guidelines by Minds, a project promoting evidence-based medicine in Japan, for observational studies. RESULTS: One RCT and 22 observational studies were included. In the RCT on infliximab, the American College of Rheumatology pediatric (ACR Pedi) 30/50/70 responses at 14 weeks were 63.8%/50.0%/22.4%, with relative risks of 1.30 (95% confidence interval [CI]: 0.94-1.79)/1.48 (95% CI: 0.95-2.29)/1.89 (95% CI: 0.81-4.40), respectively. In the observational studies, ACR Pedi 30/50/70 responses for etanercept at 12 months were 76.7%/64.7%/46.4%, respectively. Infliximab treatment caused anaphylaxis in 17% and an infusion reaction in 23% of patients. The incidence of macrophage activation syndrome, serious infection and malignancy caused by TNF inhibitors was 0%-4%. CONCLUSIONS: Thus, although TNF inhibitors were relatively safe, they were unlikely to be preferentially administered in patients with systemic JIA because of their inadequate efficacy. Further studies, particularly well-designed RCTs, are necessary to confirm the efficacy and safety of TNF inhibitors for systemic JIA.

3.
J Phys Ther Sci ; 36(8): 407-410, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39092418

RESUMEN

[Purpose] A method for evaluating integrated interpretation skills, which is an important educational goal in clinical practice, is yet to be established. This study examined the interrater reliability of a problem-solving model that was developed as a novel assessment method. [Participants and Methods] Three students created problem-solving models using fictitious case data. Ten clinical practice supervisors with at least 3 years of experience were asked to score the models, and the intraclass correlation coefficient (2, 1) was calculated. [Results] The intraclass correlation coefficient was 0.88, which indicates a good result. [Conclusion] Good interrater reliability was obtained using the problem-solving model, which suggests that this model may be used to assess integrated interpretation skills in clinical practice.

4.
Development ; 147(5)2020 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-32051172

RESUMEN

Neural remodeling is essential for the development of a functional nervous system and has been extensively studied in the metamorphosis of Drosophila Despite the crucial roles of glial cells in brain functions, including learning and behavior, little is known of how adult glial cells develop in the context of neural remodeling. Here, we show that the architecture of neuropil-glia in the adult Drosophila brain, which is composed of astrocyte-like glia (ALG) and ensheathing glia (EG), robustly develops from two different populations in the larva: the larval EG and glial cell missing-positive (gcm+ ) cells. Whereas gcm+ cells proliferate and generate adult ALG and EG, larval EG dedifferentiate, proliferate and redifferentiate into the same glial subtypes. Each glial lineage occupies a certain brain area complementary to the other, and together they form the adult neuropil-glia architecture. Both lineages require the FGF receptor Heartless to proliferate, and the homeoprotein Prospero to differentiate into ALG. Lineage-specific inhibition of gliogenesis revealed that each lineage compensates for deficiency in the proliferation of the other. Together, the lineages ensure the robust development of adult neuropil-glia, thereby ensuring a functional brain.


Asunto(s)
Astrocitos/citología , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/embriología , Proteínas del Tejido Nervioso/metabolismo , Neurogénesis/fisiología , Neurópilo/citología , Proteínas Nucleares/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Receptores de Factores de Crecimiento de Fibroblastos/metabolismo , Factores de Transcripción/metabolismo , Animales , Encéfalo/citología , Encéfalo/embriología , Linaje de la Célula/fisiología , Proliferación Celular/fisiología , Proteínas de Unión al ADN/metabolismo , Drosophila melanogaster/metabolismo , Metamorfosis Biológica/genética , Metamorfosis Biológica/fisiología , Neurogénesis/genética
5.
Nat Chem Biol ; 16(3): 351-360, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31932717

RESUMEN

Polypeptide GalNAc-transferase T3 (GalNAc-T3) regulates fibroblast growth factor 23 (FGF23) by O-glycosylating Thr178 in a furin proprotein processing motif RHT178R↓S. FGF23 regulates phosphate homeostasis and deficiency in GALNT3 or FGF23 results in hyperphosphatemia and familial tumoral calcinosis. We explored the molecular mechanism for GalNAc-T3 glycosylation of FGF23 using engineered cell models and biophysical studies including kinetics, molecular dynamics and X-ray crystallography of GalNAc-T3 complexed to glycopeptide substrates. GalNAc-T3 uses a lectin domain mediated mechanism to glycosylate Thr178 requiring previous glycosylation at Thr171. Notably, Thr178 is a poor substrate site with limiting glycosylation due to substrate clashes leading to destabilization of the catalytic domain flexible loop. We suggest GalNAc-T3 specificity for FGF23 and its ability to control circulating levels of intact FGF23 is achieved by FGF23 being a poor substrate. GalNAc-T3's structure further reveals the molecular bases for reported disease-causing mutations. Our findings provide an insight into how GalNAc-T isoenzymes achieve isoenzyme-specific nonredundant functions.


Asunto(s)
Factores de Crecimiento de Fibroblastos/química , N-Acetilgalactosaminiltransferasas/metabolismo , Animales , Células CHO , Cricetulus , Factor-23 de Crecimiento de Fibroblastos , Factores de Crecimiento de Fibroblastos/metabolismo , Glicopéptidos/química , Glicosilación , Humanos , Isoenzimas/metabolismo , Lectinas/metabolismo , N-Acetilgalactosaminiltransferasas/fisiología , Treonina/metabolismo , Polipéptido N-Acetilgalactosaminiltransferasa
6.
Exp Parasitol ; 239: 108313, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35753412

RESUMEN

Current control measures for schistosomiasis have only been partially successful in endemic areas due to socioeconomic constraints. One possibility for controlling the disease is to aim at the miracidial stage of the trematode to avoid infecting intermediate snail hosts by introducing more attractive substances for miracidia in the environment. Here, we introduce an accumulation assay of Schistosoma mansoni miracidia using a square glass tube for analysis of the positive responses of miracidia toward several substances, including snail-conditioned water of Biomphalaria glabrata, Bulinus globosus and insusceptible snails collected in the Nagasaki area in Japan. The substances are not proteins because miracidia accumulated in boiled snail-conditioned water and the secretion or emission level of substances depended on the feeding conditions of Biomphalaria glabrata. The present study also showed that substances emitted from Biomphalaria glabrata with a molecular weight around 10 kDa accumulated Schistosoma mansoni miracidia. Further, we showed that Schistosoma mansoni miracidia did not accumulate in response to mono- or disaccharides tested in the study.


Asunto(s)
Biomphalaria , Schistosoma mansoni , Animales , Biomphalaria/fisiología , Interacciones Huésped-Parásitos , Schistosoma mansoni/fisiología , Caracoles , Agua
7.
Int J Mol Sci ; 23(14)2022 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-35887043

RESUMEN

Galactose and N-acetyl-D-galactosamine-inhibitable lectin of Entamoeba histolytica have roles in the pathogenicity of intestinal amoebiasis. Igl1, the intermediate subunit lectin-1 of E. histolytica, has been shown to have both hemolytic and cytotoxic activities that reside in the C-terminus of the protein. To identify the amino acid regions responsible for these activities, recombinant proteins were prepared and used in hemolytic and cytotoxic assays. The results revealed that Igl1 has multiple domains with hemolytic and cytotoxic activities and that amino acids 787-846, 968-1028 and 1029-1088 are involved in these activities. The hemolytic activities of the fragments were partly inhibited by mannose, galactose and N-acetylgalactosamine, and glucose showed lower or negligible inhibitory effects for the activities. This is the first report of a protozoan protein with hemolytic and cytotoxic activities in multiple domains.


Asunto(s)
Entamoeba histolytica , Galactosa , Lectinas , Proteínas Protozoarias , Acetilgalactosamina/metabolismo , Citotoxinas/metabolismo , Entamoeba histolytica/metabolismo , Entamoeba histolytica/patogenicidad , Galactosa/metabolismo , Hemólisis/fisiología , Humanos , Lectinas/metabolismo , Proteínas Protozoarias/metabolismo
8.
Entropy (Basel) ; 24(5)2022 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-35626466

RESUMEN

Modern optical communication technology can realize a large-scale multilevel (or M-ary) optical signal. Investigating the quantum mechanical nature of such a large-scale M-ary optical signal is essential for a unified understanding of quantum information science and optical communication technology. This article focuses on the quantum-mechanical non-orthogonality for a collection of pure quantum states and proposes a non-orthogonality index based on the least squares error criterion in quantum detection theory. First, we define the index for linearly independent signals, and the proposed index is analyzed through numerical simulations. Next, the index is applied to a highly large-scale M-ary phase-shift keying (PSK) coherent state signal. Furthermore, the index is compared with the capacity of the pure state channel with the PSK signal. As a result, it is shown that a highly large-scale M-ary PSK coherent state signal exhibits a quantum nature even when the signal transmission power is very high. Thus, the theoretical characterization of a highly large-scale M-ary coherent state signal based on the proposed index will be the first step toward a better understanding of cutting-edge optical communication technologies such as the quantum stream cipher Y00.

9.
Genes Cells ; 25(1): 6-21, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31957229

RESUMEN

Motility often plays a decisive role in the survival of species. Five systems of motility have been studied in depth: those propelled by bacterial flagella, eukaryotic actin polymerization and the eukaryotic motor proteins myosin, kinesin and dynein. However, many organisms exhibit surprisingly diverse motilities, and advances in genomics, molecular biology and imaging have showed that those motilities have inherently independent mechanisms. This makes defining the breadth of motility nontrivial, because novel motilities may be driven by unknown mechanisms. Here, we classify the known motilities based on the unique classes of movement-producing protein architectures. Based on this criterion, the current total of independent motility systems stands at 18 types. In this perspective, we discuss these modes of motility relative to the latest phylogenetic Tree of Life and propose a history of motility. During the ~4 billion years since the emergence of life, motility arose in Bacteria with flagella and pili, and in Archaea with archaella. Newer modes of motility became possible in Eukarya with changes to the cell envelope. Presence or absence of a peptidoglycan layer, the acquisition of robust membrane dynamics, the enlargement of cells and environmental opportunities likely provided the context for the (co)evolution of novel types of motility.


Asunto(s)
Movimiento Celular/genética , Movimiento Celular/fisiología , Flagelos/metabolismo , Citoesqueleto de Actina/genética , Citoesqueleto de Actina/metabolismo , Animales , Bacterias , Evolución Biológica , Dineínas/metabolismo , Evolución Molecular , Flagelos/genética , Humanos , Cinesinas/metabolismo , Miosinas/metabolismo , Filogenia
10.
Opt Express ; 29(4): 5658-5664, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33726100

RESUMEN

We demonstrate a 4,294,967,296-quadrature amplitude modulation (QAM) based Y-00 quantum stream cipher system carrying a 160-Gb/s 16-QAM signal transmitted over 320-km SSMF. The ultra-dense QAM cipher template is realized by an integrated two-segment silicon photonics I/Q modulator.

11.
Phys Rev Lett ; 126(20): 200502, 2021 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-34110180

RESUMEN

We consider the problem of discriminating finite-dimensional quantum processes, also called quantum supermaps, that can consist of multiple time steps. Obtaining the ultimate performance for discriminating quantum processes is of fundamental importance, but is challenging mainly due to the necessity of considering all discrimination strategies allowed by quantum mechanics, including entanglement-assisted strategies and adaptive strategies. In the case in which the processes to be discriminated have internal memories, the ultimate performance would generally be more difficult to analyze. In this Letter, we present a simple upper bound on the ultimate success probability for discriminating arbitrary quantum processes. In the special case of multishot channel discrimination, it can be shown that the ultimate success probability increases by at most a constant factor determined by the given channels if the number of channel evaluations increases by one. We also present a lower bound based on Bayesian updating, which has a low computational cost. Our numerical experiments demonstrate that the proposed bounds are reasonably tight. The proposed bounds do not explicitly depend on any quantum phenomena, and can be readily extended to a general operational probabilistic theory.

12.
Molecules ; 26(18)2021 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-34576978

RESUMEN

Mucin-type O-glycosylation involves the attachment of glycans to an initial O-linked N-acetylgalactosamine (GalNAc) on serine and threonine residues on proteins. This process in mammals is initiated and regulated by a large family of 20 UDP-GalNAc: polypeptide N-acetylgalactosaminyltransferases (GalNAc-Ts) (EC 2.4.1.41). The enzymes are encoded by a large gene family (GALNTs). Two of these genes, GALNT2 and GALNT3, are known as monogenic autosomal recessive inherited disease genes with well characterized phenotypes, whereas a broad spectrum of phenotypes is associated with the remaining 18 genes. Until recently, the overlapping functionality of the 20 members of the enzyme family has hindered characterizing the specific biological roles of individual enzymes. However, recent evidence suggests that these enzymes do not have full functional redundancy and may serve specific purposes that are found in the different phenotypes described. Here, we summarize the current knowledge of GALNT and associated phenotypes.


Asunto(s)
N-Acetilgalactosaminiltransferasas , Animales , Glicosilación , N-Acetilgalactosaminiltransferasas/metabolismo , Fenotipo , Especificidad por Sustrato , Polipéptido N-Acetilgalactosaminiltransferasa
13.
Yale J Biol Med ; 94(2): 199-207, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34211341

RESUMEN

The Trypanosoma spp. cause animal and human trypanosomiasis characterized with appreciable health and economic burden mostly in developing nations. There is currently no effective therapy for this parasitic disease, due to poor drug efficacy, drug resistance, and unwanted toxicity, etc. Therefore, new anti-Trypanosoma agents are urgently needed. This study explored new series of imidazoles for anti-Trypanosoma properties in vitro and in vivo. The imidazoles showed moderate to strong and specific action against growth of T. congolense. For example, the efficacy of the imidazole compounds to restrict Trypanosoma growth in vitro was ≥ 12-fold specific towards T. congolense relative to the mammalian cells. Additionally, the in vivo study revealed that the imidazoles exhibited promising anti-Trypanosoma efficacy corroborating the in vitro anti-parasite capacity. In particular, three imidazole compounds (C1, C6, and C8) not only cleared the systemic parasite burden but cured infected rats after no death was recorded. On the other hand, the remaining five imidazole compounds (C2, C3, C4, C5, and C7) drastically reduced the systemic parasite load while extending survival time of the infected rats by 14 days as compared with control. Untreated control died 3 days post-infection, while the rats treated with diminazene aceturate were cured comparable to the results obtained for C1, C6, and C8. In conclusion, this is the first study demonstrating the potential of these new series of imidazoles to clear the systemic parasite burden in infected rats. Furthermore, a high selectivity index of imidazoles towards T. congolensein vitro and the oral LD50 in rats support anti-parasite specific action. Together, findings support the anti-parasitic prospects of the new series of imidazole derivatives.


Asunto(s)
Trypanosoma , Animales , Resistencia a Medicamentos , Imidazoles/farmacología , Ratas
14.
Parasitol Res ; 119(5): 1675-1681, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32236711

RESUMEN

Toxoplasma gondii can infect virtually all warm-blooded animals, including humans. It can differentiate between rapidly replicating tachyzoites that cause acute infection and slowly growing bradyzoites in tissue cysts. Treatment options for toxoplasmosis are challenging because current therapies cannot eradicate the latent T. gondii infection that is mainly caused by the bradyzoite forms. Accordingly, recurrence of infection is a problem for immunocompromised patients and congenitally infected patients. Protein kinases have been widely studied in eukaryotic cells, and while little is known about signaling in Toxoplasma infection, it is likely that protein kinases play a key role in parasite proliferation, differentiation, and probably invasion. To identify optimized new kinase inhibitors for drug development against T. gondii, we screened a library of kinase inhibitor compounds for anti-Toxoplasma activity and host cell cytotoxicity. Pyrimethamine served as a positive control and 0.5% DMSO was used as a negative control. Among the 80 compounds screened, 6 compounds demonstrated ≥ 80% parasite growth inhibition at concentrations at which 5 compounds did not suppress host cell viability, while 3 kinase inhibitors (Bay 11-7082, Tyrphostin AG 1295 and PD-98059) had suppressive effects individually on parasite growth and host cell invasion, but did not strongly induce bradyzoite formation.


Asunto(s)
Antiprotozoarios/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Quinasas/efectos de los fármacos , Toxoplasma/crecimiento & desarrollo , Toxoplasmosis/tratamiento farmacológico , Animales , Diferenciación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Flavonoides/farmacología , Humanos , Nitrilos/farmacología , Pirimetamina/farmacología , Transducción de Señal/efectos de los fármacos , Sulfonas/farmacología , Toxoplasma/efectos de los fármacos , Toxoplasma/patogenicidad , Toxoplasmosis/patología , Tirfostinos/farmacología
15.
Parasitol Res ; 119(6): 1925-1941, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32279093

RESUMEN

Toxoplasmosis is a common parasitic disease caused by Toxoplasma gondii. Limitations of available treatments motivate the search for better therapies for toxoplasmosis. In this study, we synthesized a series of new imidazole derivatives: bis-imidazoles (compounds 1-8), phenyl-substituted 1H-imidazoles (compounds 9-19), and thiopene-imidazoles (compounds 20-26). All these compounds were assessed for in vitro potential to restrict the growth of T. gondii. To explore the structure-activity relationships, molecular analyses and bioactivity prediction studies were performed using a standard molecular model. The in vitro results, in combination with the predictive model, revealed that the imidazole derivatives have excellent selectivity activity against T. gondii versus the host cells. Of the 26 compounds screened, five imidazole derivatives (compounds 10, 11, 18, 20, and 21) shared a specific structural moiety and exhibited significantly high selectivity (> 1176 to > 27,666) towards the parasite versus the host cells. These imidazole derivatives are potential candidates for further studies. We show evidence that supports the antiparasitic action of the imidazole derivatives. The findings are promising in that they reinforce the prospects of imidazole derivatives as alternative and effective antiparasitic therapy as well as providing evidence for a probable biological mechanism.


Asunto(s)
Antiparasitarios/química , Antiparasitarios/farmacología , Imidazoles/química , Imidazoles/farmacología , Toxoplasma/efectos de los fármacos , Animales , Células Cultivadas , Humanos , Imidazoles/síntesis química , Modelos Moleculares , Relación Estructura-Actividad , Toxoplasmosis/parasitología
16.
J Enzyme Inhib Med Chem ; 34(1): 171-178, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30451014

RESUMEN

Inosine 5'-monophosphate dehydrogenase (IMPDH) is an essential enzyme for the production of guanine nucleotides. Disruption of IMPDH activity has been explored as a therapeutic strategy for numerous purposes, such as for anticancer, immunosuppression, antiviral, and antimicrobial therapy. In the present study, we established a luciferase-based high-throughput screening system to identify IMPDH inhibitors from our chemical library of known bioactive small molecules. The screening of 1400 compounds resulted in the discovery of three irreversible inhibitors: disulfiram, bronopol, and ebselen. Each compound has a distinct chemical moiety that differs from other reported IMPDH inhibitors. Further evaluation revealed that these compounds are potent inhibitors of IMPDHs with kon values of 0.7 × 104 to 9.3 × 104 M-1·s-1. Both disulfiram and bronopol exerted similar degree of inhibition to protozoan and mammalian IMPDHs. Ebselen showed an intriguing difference in mode of inhibition for different IMPDHs, with reversible and irreversible inhibition to each Cryptosporidium parvum IMPDH and human IMPDH type II, respectively. In the preliminary efficacy experiment against cryptosporidiosis in severe combined immunodeficiency (SCID) mouse, a decrease in the number of oocyst shed was observed upon the oral administration of disulfiram and bronopol, providing an early clinical proof-of-concept for further utilization of these compounds as IMPDH inhibitors.


Asunto(s)
Descubrimiento de Drogas , Reposicionamiento de Medicamentos , Inhibidores Enzimáticos/aislamiento & purificación , Inhibidores Enzimáticos/farmacología , Ensayos Analíticos de Alto Rendimiento/métodos , IMP Deshidrogenasa/antagonistas & inhibidores , Animales , Azoles/química , Azoles/aislamiento & purificación , Azoles/farmacología , Cryptosporidium parvum/enzimología , Disulfiram/química , Disulfiram/aislamiento & purificación , Disulfiram/farmacología , Inhibidores Enzimáticos/química , Humanos , IMP Deshidrogenasa/metabolismo , Isoindoles , Cinética , Ratones , Ratones SCID , Compuestos de Organoselenio/química , Compuestos de Organoselenio/aislamiento & purificación , Compuestos de Organoselenio/farmacología , Prueba de Estudio Conceptual , Glicoles de Propileno/química , Glicoles de Propileno/aislamiento & purificación , Glicoles de Propileno/farmacología , Bibliotecas de Moléculas Pequeñas
17.
Folia Parasitol (Praha) ; 662019 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-30799835

RESUMEN

Toxoplasmosis is a common parasitic disease caused by Toxoplasma gondii (Nicolle et Manceaux, 1908), an obligate parasite capable of infecting a range of cell types in almost all warm-blooded animals. Upon infecting an intermediate host, the parasites differentiate into tachyzoites which rapidly infect host tissues. Usually, the invading parasites are cleared by the immune system and administered drugs, but some tachyzoites differentiate into bradyzoites forming tissue cysts. These tissue cysts could serve as a source for re-infection and exacerbations. Currently, treatment for toxoplasmosis is limited and, moreover, there are no drugs for treating the cystic stage thus rendering toxoplasmosis a global burden. Recently, we demonstrated that inorganic nanoparticles showed promising activity against the tachyzoite stage T. gondii. In the present study, we evaluated nanoparticles for effect on bradyzoite formation in vitro. Data revealed that the nanoparticles limited bradyzoite burden in vitro. Further, the nanoparticles decreased the bradyzoite-specific BAG-1 promoter activity relative to the untreated control under a bradyzoite-inducing culture condition, even though this reduction in BAG-1 promoter activity waned with increasing concentrations of nanoparticles. In contrast, a parallel experiment under normal cell culture conditions showed that the nanoparticle treatment mildly increased the BAG-1 promoter activity relative to the untreated control. Taken together, the findings are evidence that nanoparticles not only possess anti-tachyzoite potential but they also have anti-bradyzoite potential in vitro.


Asunto(s)
Coccidiostáticos/farmacología , Merozoítos/efectos de los fármacos , Nanopartículas del Metal , Toxoplasma/efectos de los fármacos , Merozoítos/crecimiento & desarrollo , Toxoplasma/crecimiento & desarrollo
18.
Dev Dyn ; 247(1): 85-93, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28791751

RESUMEN

Although the central nervous system does not regenerate, injury induces repair and regenerative responses in glial cells. In mammals, activated microglia clear up apoptotic cells and debris resulting from the injury, astrocytes form a scar that contains the lesion, and NG2-glia elicit a prominent regenerative response. NG2-glia regenerate themselves and differentiate into oligodendrocytes, which remyelinate axons leading to some recovery of locomotion. The regenerative response of glial cells is evolutionarily conserved across the animals and Drosophila genetics revealed an underlying gene network. This involves the genes Notch, kon-tiki, eiger, dorsal, and prospero, homologues of mammalian Notch1, ng2, TNF, NFκB, and prox1, respectively. Feedback loops between these genes enable a surge in proliferation in response to injury and ensuing differentiation. Negative feedback sets a timer for proliferation, and prevents uncontrolled growth that could lead to glioma. Remarkable parallels are found in these genetic relationships between fruit flies and mammals. Drosophila findings provide insights into gene functions that could be manipulated in stem cells and progenitors for therapeutic repair. Developmental Dynamics 247:85-93, 2018. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Lesiones Encefálicas/fisiopatología , Redes Reguladoras de Genes , Neuroglía/fisiología , Regeneración/genética , Traumatismos de la Médula Espinal/fisiopatología , Animales , Lesiones Encefálicas/genética , Traumatismos de la Médula Espinal/genética
19.
J Virol ; 91(15)2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28539443

RESUMEN

Akabane virus (AKAV) and Schmallenberg virus (SBV) are members of the genus Orthobunyavirus, which are transmitted by arthropod vectors with a broad cellular tropism in vitro as well as in vivo Both AKAV and SBV cause arthrogryposis-hydranencephaly syndrome in ruminants. The main cellular receptor and attachment factor for entry of these orthobunyaviruses are unknown. Here, we found that AKAV and SBV infections were inhibited by the addition of heparin or enzymatic removal of cell surface heparan sulfates. To confirm this finding, we prepared heparan sulfate proteoglycan (HSPG)-knockout (KO) cells by using a clustered regularly interspaced short palindromic repeat (CRISPR)-Cas9 system and measured the quantities of binding of these viruses to cell surfaces. We observed a substantial reduction in AKAV and SBV binding to cells, limiting the infections by these viruses. These data demonstrate that HSPGs are important cellular attachment factors for AKAV and SBV, at least in vitro, to promote virus replication in susceptible cells.IMPORTANCE AKAV and SBV are the etiological agents of arthrogryposis-hydranencephaly syndrome in ruminants, which causes considerable economic losses in the livestock industry. Here, we identified heparan sulfate proteoglycan as a major cellular attachment factor for the entry of AKAV and SBV. Moreover, we found that heparin is a strong inhibitor of AKAV and SBV infections. Revealing the molecular mechanisms of virus-host interactions is critical in order to understand virus biology and develop novel live attenuated vaccines.


Asunto(s)
Proteoglicanos de Heparán Sulfato/metabolismo , Orthobunyavirus/fisiología , Receptores Virales/metabolismo , Acoplamiento Viral , Animales , Línea Celular , Cricetinae , Humanos
20.
Malar J ; 17(1): 244, 2018 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-29941026

RESUMEN

BACKGROUND: Malaria is a major infectious disease in the world. In 2015, approximately 212 million people were infected and 429,000 people were killed by this disease. Plasmodium falciparum, which causes falciparum malaria, is becoming resistant to artemisinin (ART) in Southeast Asia; therefore, new anti-malarial drugs are urgently needed. Some excellent anti-malarial drugs, such as quinine or ART, were originally obtained from natural plants. Hence, the authors screened a natural product library comprising traditional Chinese medicines (TCMs) to identify compounds/extracts with anti-malarial effects. METHODS: The authors performed three assays: a malaria growth inhibition assay (GIA), a cytotoxicity assay, and a malaria stage-specific GIA. The malaria GIA revealed the anti-malarial ability and half-maximal inhibitory concentrations (IC50) of the natural products, whereas the malaria stage-specific GIA revealed the point in the malaria life cycle where the products exerted their anti-malarial effects. The toxicity of the products to the host cells was evaluated with the cytotoxicity assay. RESULTS: Four natural compounds (berberine chloride, coptisine chloride, palmatine chloride, and dehydrocorydaline nitrate) showed strong anti-malarial effects (IC50 < 50 nM), and low cytotoxicity (cell viability > 90%) using P. falciparum 3D7 strain. Two natural extracts (Phellodendri cortex and Coptidis rhizoma) also showed strong antiplasmodial effects (IC50 < 1 µg/ml), and low cytotoxicity (cell viability > 80%). These natural products also demonstrated anti-malarial capability during the trophozoite and schizont stages of the malaria life cycle. CONCLUSIONS: The authors identified four compounds (berberine chloride, coptisine chloride, palmatine chloride, and dehydrocorydaline nitrate) and two extracts (Phellodendri cortex and Coptidis rhizoma) with anti-malarial activity, neither of which had previously been described. The IC50 values of the compounds were comparable to that of chloroquine and better than that of pyrimethamine. These compounds and extracts derived from TCMs thus show promise as potential future anti-malarial drugs.


Asunto(s)
Antimaláricos/farmacología , Medicina Tradicional China , Extractos Vegetales/farmacología , Plasmodium falciparum/efectos de los fármacos , Humanos , Malaria Falciparum/prevención & control
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