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1.
EMBO J ; 39(8): e102811, 2020 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-32175624

RESUMEN

The C9orf72 repeat expansion causes amyotrophic lateral sclerosis and frontotemporal dementia, but the poor correlation between C9orf72-specific pathology and TDP-43 pathology linked to neurodegeneration hinders targeted therapeutic development. Here, we addressed the role of the aggregating dipeptide repeat proteins resulting from unconventional translation of the repeat in all reading frames. Poly-GA promoted cytoplasmic mislocalization and aggregation of TDP-43 non-cell-autonomously, and anti-GA antibodies ameliorated TDP-43 mislocalization in both donor and receiver cells. Cell-to-cell transmission of poly-GA inhibited proteasome function in neighboring cells. Importantly, proteasome inhibition led to the accumulation of TDP-43 ubiquitinated within the nuclear localization signal (NLS) at lysine 95. Mutagenesis of this ubiquitination site completely blocked poly-GA-dependent mislocalization of TDP-43. Boosting proteasome function with rolipram reduced both poly-GA and TDP-43 aggregation. Our data from cell lines, primary neurons, transgenic mice, and patient tissue suggest that poly-GA promotes TDP-43 aggregation by inhibiting the proteasome cell-autonomously and non-cell-autonomously, which can be prevented by inhibiting poly-GA transmission with antibodies or boosting proteasome activity with rolipram.


Asunto(s)
Esclerosis Amiotrófica Lateral/patología , Proteína C9orf72/metabolismo , Proteínas de Unión al ADN/metabolismo , Dipéptidos/metabolismo , Demencia Frontotemporal/patología , Transporte Activo de Núcleo Celular , Esclerosis Amiotrófica Lateral/metabolismo , Animales , Proteína C9orf72/genética , Citoplasma/metabolismo , Proteínas de Unión al ADN/genética , Femenino , Demencia Frontotemporal/metabolismo , Células HeLa , Humanos , Masculino , Ratones , Neuronas/metabolismo , Señales de Localización Nuclear , Complejo de la Endopetidasa Proteasomal/metabolismo , Agregación Patológica de Proteínas , Ubiquitina/metabolismo
2.
Chem Rev ; 121(8): 4561-4677, 2021 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-33705116

RESUMEN

The complex interaction of cells with biomaterials (i.e., materiobiology) plays an increasingly pivotal role in the development of novel implants, biomedical devices, and tissue engineering scaffolds to treat diseases, aid in the restoration of bodily functions, construct healthy tissues, or regenerate diseased ones. However, the conventional approaches are incapable of screening the huge amount of potential material parameter combinations to identify the optimal cell responses and involve a combination of serendipity and many series of trial-and-error experiments. For advanced tissue engineering and regenerative medicine, highly efficient and complex bioanalysis platforms are expected to explore the complex interaction of cells with biomaterials using combinatorial approaches that offer desired complex microenvironments during healing, development, and homeostasis. In this review, we first introduce materiobiology and its high-throughput screening (HTS). Then we present an in-depth of the recent progress of 2D/3D HTS platforms (i.e., gradient and microarray) in the principle, preparation, screening for materiobiology, and combination with other advanced technologies. The Compendium for Biomaterial Transcriptomics and high content imaging, computational simulations, and their translation toward commercial and clinical uses are highlighted. In the final section, current challenges and future perspectives are discussed. High-throughput experimentation within the field of materiobiology enables the elucidation of the relationships between biomaterial properties and biological behavior and thereby serves as a potential tool for accelerating the development of high-performance biomaterials.


Asunto(s)
Materiales Biocompatibles/química , Ensayos Analíticos de Alto Rendimiento/métodos , Animales , Humanos , Ciencia de los Materiales/métodos
3.
Bioorg Chem ; 136: 106550, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37121105

RESUMEN

The drugs targeting the PD-1/PD-L1 pathway have gained abundant clinical applications for cancer immunotherapy. However, only a part of patients benefit from such immunotherapy. Thus, brilliant novel tactic to increase the response rate of patients is on the agenda. Nanocarriers, particularly the rationally designed intelligent delivery systems with controllable therapeutic agent release ability and improved tumor targeting capacity, are firmly recommended. In light of this, state-of-the-art nanocarriers that are responsive to tumor-specific microenvironments (internal stimuli, including tumor acidic microenvironment, high level of GSH and ROS, specifically upregulated enzymes) or external stimuli (e.g., light, ultrasound, radiation) and release the target immunomodulators at tumor sites feature the advantages of increased anti-tumor potency but decreased off-target toxicity. Given the fantastic past achievements and the rapid developments in this field, the future is promising. In this review, intelligent delivery platforms targeting the PD-1/PD-L1 axis are attentively appraised. Specifically, mechanisms of the action of these stimuli-responsive drug release platforms are summarized to raise some guidelines for prior PD-1/PD-L1-based nanocarrier designs. Finally, the conclusion and outlook in intelligent delivery system targeting PD-1/PD-L1 pathway for cancer immunotherapy are outlined.


Asunto(s)
Neoplasias , Receptor de Muerte Celular Programada 1 , Humanos , Antígeno B7-H1/metabolismo , Inmunoterapia , Neoplasias/tratamiento farmacológico
4.
J Nanobiotechnology ; 21(1): 167, 2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37231475

RESUMEN

BACKGROUND: Carbon dots (CDs), as excellent antibacterial nanomaterials, have gained great attention in treating infection-induced diseases such as periodontitis and stomatitis. Given the eventual exposure of CDs to the intestine, elucidating the effect of CDs on intestinal health is required for the safety evaluation of CDs. RESULTS: Herein, CDs extracted from ε-poly-L-lysine (PL) were chosen to explore the modulation effect of CDs on probiotic behavior in vitro and intestinal remodeling in vivo. Results verify that PL-CDs negatively regulate Lactobacillus rhamnosus (L. rhamnosus) growth via increasing reactive oxygen species (ROS) production and reducing the antioxidant activity, which subsequently destroys membrane permeability and integrity. PL-CDs are also inclined to inhibit cell viability and accelerate cell apoptosis. In vivo, the gavage of PL-CDs is verified to induce inflammatory infiltration and barrier damage in mice. Moreover, PL-CDs are found to increase the Firmicutes to Bacteroidota (F/B) ratio and the relative abundance of Lachnospiraceae while decreasing that of Muribaculaceae. CONCLUSION: Overall, these evidences indicate that PL-CDs may inevitably result in intestinal flora dysbiosis via inhibiting probiotic growth and simultaneously activating intestinal inflammation, thus causing pathological damage to the intestine, which provides an effective and insightful reference for the potential risk of CDs from the perspective of intestinal remodeling.


Asunto(s)
Carbono , Microbioma Gastrointestinal , Animales , Ratones , Carbono/farmacología , Disbiosis , Intestinos , Inflamación
5.
Mol Psychiatry ; 26(10): 5824-5832, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34561610

RESUMEN

Frontotemporal dementia (FTD) is a clinically and genetically heterogeneous disorder. To which extent genetic aberrations dictate clinical presentation remains elusive. We investigated the spectrum of genetic causes and assessed the genotype-driven differences in biomarker profiles, disease severity and clinical manifestation by recruiting 509 FTD patients from different centers of the German FTLD consortium where individuals were clinically assessed including biomarker analysis. Exome sequencing as well as C9orf72 repeat analysis were performed in all patients. These genetic analyses resulted in a diagnostic yield of 18.1%. Pathogenic variants in C9orf72 (n = 47), GRN (n = 26), MAPT (n = 11), TBK1 (n = 5), FUS (n = 1), TARDBP (n = 1), and CTSF (n = 1) were identified across all clinical subtypes of FTD. TBK1-associated FTD was frequent accounting for 5.4% of solved cases. Detection of a homozygous missense variant verified CTSF as an FTD gene. ABCA7 was identified as a candidate gene for monogenic FTD. The distribution of APOE alleles did not differ significantly between FTD patients and the average population. Male sex was weakly associated with clinical manifestation of the behavioral variant of FTD. Age of onset was lowest in MAPT patients. Further, high CSF neurofilament light chain levels were found to be related to GRN-associated FTD. Our study provides large-scale retrospective clinico-genetic data such as on disease manifestation and progression of FTD. These data will be relevant for counseling patients and their families.


Asunto(s)
Demencia Frontotemporal , Proteína C9orf72/genética , Demencia Frontotemporal/genética , Genotipo , Humanos , Masculino , Mutación , Estudios Retrospectivos , Secuenciación del Exoma , Proteínas tau/genética
6.
J Psychiatry Neurosci ; 47(2): E153-E161, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35477683

RESUMEN

BACKGROUND: At present, the use of repetitive transcranial magnetic stimulation (rTMS) for generalized anxiety disorder (GAD) is limited to single-site interventions. We investigated whether dual-site frontoparietal stimulation delivered using cortical-cortical paired associative stimulation (ccPAS) had stronger clinical efficacy than single-site stimulation in patients with GAD. METHODS: We randomized 50 patients with GAD to 1 Hz rTMS (10 sessions) using 1 of the following protocols: single-site stimulation over the right dorsolateral prefrontal cortex (dlPFC; 1500 pulses per session); single-site stimulation over the right posterior parietal cortex (PPC; 1500 pulses per session); repetitive dual-site ccPAS (rds-ccPAS) over the right dlPFC and right PPC with 1500 pulses per session (rd-ccPAS-1500); or rds-ccPAS over the right dlPFC and right PPC with 750 pulses per session (rd-ccPAS-750). Both rds-ccPAS treatments used a between-site interval of 100 ms. RESULTS: Clinical scores for anxiety, depression and insomnia were reduced in all 4 groups after treatment. We found greater improvements in anxiety symptoms in the rds-ccPAS-1500 group compared to the rds-ccPAS-750 and single-site groups. We found greater improvements in depression symptoms and insomnia in the rds-PAS-1500 group compared to the single-site groups. The rds-ccPAS-1500 group also showed significant or trend-level improvements in anxiety symptoms and insomnia at 10-day and 1-month followup. More patients responded to treatment with rds-ccPAS-1500 than with single-site stimulation. The between-group differences in response rates persisted to the 3-month follow-up. Treatment using rds-ccPAS with a between-site interval of 100 ms induced a more significant improvement than the between-site interval of 50 ms we evaluated in a previous study. LIMITATIONS: These results need to be replicated in a larger sample using sham control and equal-pulse single-site stimulation. CONCLUSION: Frontoparietal rds-ccPAS may be a better treatment option for GAD.


Asunto(s)
Trastornos de Ansiedad , Estimulación Magnética Transcraneal , Trastornos de Ansiedad/terapia , Humanos , Lóbulo Parietal/fisiología , Proyectos Piloto , Trastornos del Inicio y del Mantenimiento del Sueño , Estimulación Magnética Transcraneal/métodos , Resultado del Tratamiento
7.
J Nanobiotechnology ; 20(1): 138, 2022 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-35300702

RESUMEN

Unintended pregnancy is a global issue with serious ramifications for women, their families, and society, including abortion, infertility, and maternal death. Although existing contraceptive strategies have been widely used in people's lives, there have not been satisfactory feedbacks due to low contraceptive efficacy and related side effects (e.g., decreased sexuality, menstrual cycle disorder, and even lifelong infertility). In recent years, biomaterials-based long-acting reversible contraception has received increasing attention from the viewpoint of fundamental research and practical applications mainly owing to improved delivery routes and controlled drug delivery. This review summarizes recent progress in advanced biomaterials for long-acting reversible contraception via various delivery routes, including subcutaneous implant, transdermal patch, oral administration, vaginal ring, intrauterine device, fallopian tube occlusion, vas deferens contraception, and Intravenous administration. In addition, biomaterials, especially nanomaterials, still need to be improved and prospects for the future in contraception are mentioned.


Asunto(s)
Anticonceptivos Femeninos , Dispositivos Intrauterinos , Anticoncepción Reversible de Larga Duración , Materiales Biocompatibles , Anticoncepción , Anticonceptivos Femeninos/uso terapéutico , Femenino , Humanos , Embarazo
8.
J Nanobiotechnology ; 20(1): 289, 2022 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-35717234

RESUMEN

Inorganic nanoparticles (INPs) have been paid great attention in the field of oncology in recent past years since they have enormous potential in drug delivery, gene delivery, photodynamic therapy (PDT), photothermal therapy (PTT), bio-imaging, driven motion, etc. To overcome the innate limitations of the conventional INPs, such as fast elimination by the immune system, low accumulation in tumor sites, and severe toxicity to the organism, great efforts have recently been made to modify naked INPs, facilitating their clinical application. Taking inspiration from nature, considerable researchers have exploited cell membrane-camouflaged INPs (CMCINPs) by coating various cell membranes onto INPs. CMCINPs naturally inherit the surface adhesive molecules, receptors, and functional proteins from the original cell membrane, making them versatile as the natural cells. In order to give a timely and representative review on this rapidly developing research subject, we highlighted recent advances in CMCINPs with superior unique merits of various INPs and natural cell membranes for cancer therapy applications. The opportunity and obstacles of CMCINPs for clinical translation were also discussed. The review is expected to assist researchers in better eliciting the effect of CMCINPs for the management of tumors and may catalyze breakthroughs in this area.


Asunto(s)
Hipertermia Inducida , Nanopartículas , Neoplasias , Fotoquimioterapia , Membrana Celular , Humanos , Hipertermia Inducida/métodos , Nanopartículas/uso terapéutico , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Fototerapia/métodos
9.
J Nanobiotechnology ; 20(1): 321, 2022 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-35836267

RESUMEN

Enterococcus faecalis (E. faecalis) biofilm-associated persistent endodontic infections (PEIs) are one of the most common tooth lesions, causing chronic periapical periodontitis, root resorption, and even tooth loss. Clinical root canal disinfectants have the risk of damaging soft tissues (e.g., mucosa and tongue) and teeth in the oral cavity, unsatisfactory to the therapy of PEIs. Nanomaterials with remarkable antibacterial properties and good biocompatibility have been developed as a promising strategy for removing pathogenic bacteria and related biofilm. Herein, carbon dots (CDs) derived from fucoidan (FD) are prepared through a one-pot hydrothermal method for the treatment of PEIs. The prepared FDCDs (7.15 nm) with sulfate groups and fluorescence property are well dispersed and stable in water. Further, it is found that in vitro FDCDs display excellent inhibiting effects on E. faecalis and its biofilm by inducing the formation of intracellular and extracellular reactive oxygen species and altering bacterial permeability. Importantly, the FDCDs penetrated the root canals and dentinal tubules, removing located E. faecalis biofilm. Moreover, the cellular assays show that the developed FDCDs have satisfactory cytocompatibility and promote macrophage recruitment. Thus, the developed FDCDs hold great potential for the management of PEIs.


Asunto(s)
Enterococcus faecalis , Irrigantes del Conducto Radicular , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Biopelículas , Carbono , Polisacáridos , Irrigantes del Conducto Radicular/farmacología , Irrigantes del Conducto Radicular/uso terapéutico , Hipoclorito de Sodio/farmacología , Hipoclorito de Sodio/uso terapéutico
10.
J Nanobiotechnology ; 19(1): 353, 2021 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-34717648

RESUMEN

Titanium (Ti) implants are widely used in dentistry and orthopedics owing to their excellent corrosion resistance, biocompatibility, and mechanical properties, which have gained increasing attention from the viewpoints of fundamental research and practical applications. Also, numerous studies have been carried out to fine-tune the micro/nanostructures of Ti and/or incorporate chemical elements to improve overall implant performance. Zinc oxide nanoparticles (nano-ZnO) are well-known for their good antibacterial properties and low cytotoxicity along with their ability to synergize with a variety of substances, which have received increasingly widespread attention as biomodification materials for implants. In this review, we summarize recent research progress on nano-ZnO modified Ti-implants. Their preparation methods of nano-ZnO modified Ti-implants are introduced, followed by a further presentation of the antibacterial, osteogenic, and anti-corrosion properties of these implants. Finally, challenges and future opportunities for nano-ZnO modified Ti-implants are proposed.


Asunto(s)
Antibacterianos/farmacología , Osteogénesis/efectos de los fármacos , Prótesis e Implantes , Titanio/química , Óxido de Zinc/química , Corrosión , Rayos Láser , Nanopartículas , Nanoestructuras , Nanotubos , Propiedades de Superficie
11.
J Nanobiotechnology ; 19(1): 216, 2021 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-34281552

RESUMEN

Sepsis, the syndrome of infection complicated by acute organ dysfunction, is a serious and growing global problem, which not only leads to enormous economic losses but also becomes one of the leading causes of mortality in the intensive care unit. The detection of sepsis-related pathogens and biomarkers in the early stage plays a critical role in selecting appropriate antibiotics or other drugs, thereby preventing the emergence of dangerous phases and saving human lives. There are numerous demerits in conventional detection strategies, such as high cost, low efficiency, as well as lacking of sensitivity and selectivity. Recently, the aptamer-based biosensor is an emerging strategy for reasonable sepsis diagnosis because of its accessibility, rapidity, and stability. In this review, we first introduce the screening of suitable aptamer. Further, recent advances of aptamer-based biosensors in the detection of bacteria and biomarkers for the diagnosis of sepsis are summarized. Finally, the review proposes a brief forecast of challenges and future directions with highly promising aptamer-based biosensors.


Asunto(s)
Técnicas Biosensibles , Nanoestructuras , Sepsis/diagnóstico , Aptámeros de Nucleótidos , Bacterias , Biomarcadores , Citocinas , Humanos
12.
Hepatobiliary Pancreat Dis Int ; 20(5): 460-468, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34233849

RESUMEN

BACKGROUND: Liver cirrhosis is associated with immune deficiency, which causes these patients to be susceptible to various infections, including cryptococcus infection. Mortality in cirrhotic patients with cryptococcosis has increased. The present study was to explore the risk factors of mortality and the predictive ability of different prognostic models. METHODS: Forty-seven cirrhotic patients with cryptococcosis at a tertiary care hospital were included in this retrospective study. Data on demographics, clinical parameters, laboratory exams, diagnostic methods, medication during hospitalization, severity scores and prognosis were collected and analyzed. Student's t test and Mann-Whitney test were used to compare characteristics of survivors and non-survivors at a 90-day follow-up and cerebrospinal fluid (CSF) manifestations of cryptococcal meningitis. Multivariate Cox regression analysis was used to identify the independent risk factors for mortality. Kaplan-Meier curves were used to analyze patient survival. Receiver operating characteristic (ROC) curves were used to evaluate the different prognostic factors. RESULTS: The 30- and 90-day survival rates were 93.6% and 80.9%, respectively, in cirrhotic patients with cryptococcosis. Cryptogenic liver diseases [hazard ratio (HR) = 7.567, 95% confidence interval (CI): 1.616-35.428, P = 0.010], activated partial thromboplastin time (APTT) (HR = 1.117, 95% CI: 1.016-1.229, P = 0.022) and Child-Pugh score (HR = 2.146, 95% CI: 1.314-3.504, P = 0.002) were risk factors for 90-day mortality in cirrhotic patients with cryptococcosis. Platelet count (HR = 0.965, 95% CI: 0.940-0.991, P = 0.008) was a protective factor. APTT (HR = 1.120, 95% CI: 1.044-1.202, P = 0.002) and Child-Pugh score (HR = 1.637, 95% CI: 1.086-2.469, P = 0.019) were risk factors for 90-day mortality in cirrhotic patients with cryptococcal meningitis. There was significant difference in the percentage of lymphocytes in CSF between survivors and non-survivors [60.0 (35.0-75.0) vs. 95.0 (83.8-97.2), P < 0.001]. The model of end-stage liver disease-sodium (MELD-Na) score was more accurate for predicting 30-day mortality both in patients with cryptococcosis [area under curve (AUC): 0.826, 95% CI: 0.618-1.000] and those with cryptococcal meningitis (AUC: 0.742, 95% CI: 0.560-0.924); Child-Pugh score was more useful for predicting 90-day mortality in patients with cryptococcosis (AUC: 0.823, 95% CI: 0.646-1.000) and those with cryptococcal meningitis (AUC: 0.815, 95% CI: 0.670-0.960). CONCLUSIONS: These results showed that cryptogenic liver diseases, APTT and Child-Pugh score were associated with mortality in cirrhotic patients with cryptococcosis and cryptococcal meningitis. MELD-Na score was important for predicting 30-day mortality, and Child-Pugh score was critical for predicting 90-day mortality.


Asunto(s)
Meningitis Criptocócica , Humanos , Cirrosis Hepática/diagnóstico , Valor Predictivo de las Pruebas , Pronóstico , Curva ROC , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Sodio
13.
Biochem Biophys Res Commun ; 526(3): 841-847, 2020 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-32278550

RESUMEN

BACKGROUND: In-stent restenosis (ISR) is a complex disease that occurs after coronary stenting procedures. The development of quality materials and improvement of our understanding on significant factors regulating ISR are essential for enhancing prognosis. Vascular smooth muscle cells (VSMCs) are the main constituent cells of blood vessel walls, and dysfunction of VMSCs can exacerbate ISR. Accordingly, in this study, we explored the influence of wrinkled material topography on the biological functions of VSMCs. METHODS: Polydimethylsiloxane with a wrinkled topography was synthesized using elastomer base and crosslinking and observed by atomic force microscopy. VSMC proliferation, apoptosis, and morphology were determined by Cell Counting Kit-8 assays, fluorescence-assisted cell sorting, and phalloidin staining. α-Smooth muscle actin (α-SMA), major histocompatibility complex (MHC), and calponin 1 (CNN-1) expression levels were measured by quantitative real-time polymerase chain reaction and western blotting. Moreover, p53 and cleaved caspase-3 expression levels were evaluated by western blotting in VSMCs to assess apoptotic induction. RESULTS: Surface topographies were not associated with a clear orientation or elongation of VSMCs. The number of cells was increased on wrinkled surfaces (0.7 µm in amplitude, and 3 µm in wavelength [W3]) compared with that on other surfaces, contributing to continuously increased cell proliferation. Moreover, interactions of VSMCs with the W3 surface suppressed phenotypic switching, resulting in ISR via regulation of α-SMA, calponin-1, and SM-MHC expression. The surface with an amplitude of 0.05 µm and a wavelength of 0.5 µm (W0.5) promoted apoptosis by inducing caspase 3 and p53 activities. CONCLUSION: Introduction of aligned topographies on biomaterial scaffolds could provide physical cues to modulate VSMC responses for engineering vascular constructs. Materials with wrinkled topographies could have applications in the development of stents to reduce ISR.


Asunto(s)
Apoptosis , Dimetilpolisiloxanos/química , Músculo Liso Vascular/metabolismo , Fenotipo , Andamios del Tejido/química , Actinas/genética , Actinas/metabolismo , Fenómenos Biomecánicos , Proteínas de Unión al Calcio/genética , Proteínas de Unión al Calcio/metabolismo , Caspasa 3/genética , Caspasa 3/metabolismo , Línea Celular , Proliferación Celular , Células Cultivadas , Reactivos de Enlaces Cruzados/química , Regulación de la Expresión Génica , Humanos , Complejo Mayor de Histocompatibilidad/genética , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , Microscopía de Fuerza Atómica , Músculo Liso Vascular/citología , Propiedades de Superficie , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Calponinas
14.
Acta Neuropathol ; 139(1): 99-118, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31642962

RESUMEN

Repeat expansion in C9orf72 causes amyotrophic lateral sclerosis and frontotemporal lobar degeneration. Expanded sense and antisense repeat RNA transcripts in C9orf72 are translated into five dipeptide-repeat proteins (DPRs) in an AUG-independent manner. We previously identified the heterogeneous ribonucleoprotein (hnRNP) A3 as an interactor of the sense repeat RNA that reduces its translation into DPRs. Furthermore, we found that hnRNPA3 is depleted from the nucleus and partially mislocalized to cytoplasmic poly-GA inclusions in C9orf72 patients, suggesting that poly-GA sequesters hnRNPA3 within the cytoplasm. We now demonstrate that hnRNPA3 also binds to the antisense repeat RNA. Both DPR production and deposition from sense and antisense RNA repeats are increased upon hnRNPA3 reduction. All DPRs induced DNA double strand breaks (DSB), which was further enhanced upon reduction of hnRNPA3. Poly-glycine-arginine and poly-proline-arginine increased foci formed by phosphorylated Ataxia Telangiectasia Mutated (pATM), a major sensor of DSBs, whereas poly-glycine-alanine (poly-GA) evoked a reduction of pATM foci. In dentate gyri of C9orf72 patients, lower nuclear hnRNPA3 levels were associated with increased DNA damage. Moreover, enhanced poly-GA deposition correlated with reduced pATM foci. Since cytoplasmic pATM deposits partially colocalized with poly-GA deposits, these results suggest that poly-GA, the most frequent DPR observed in C9orf72 patients, differentially causes DNA damage and that poly-GA selectively sequesters pATM in the cytoplasm inhibiting its recruitment to sites of DNA damage. Thus, mislocalization of nuclear hnRNPA3 caused by poly-GA leads to increased poly-GA production, which partially depletes pATM, and consequently enhances DSB.


Asunto(s)
Esclerosis Amiotrófica Lateral/genética , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Proteína C9orf72/genética , Repeticiones de Dinucleótido/fisiología , Degeneración Lobar Frontotemporal/genética , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B/metabolismo , Anciano , Esclerosis Amiotrófica Lateral/metabolismo , Daño del ADN/genética , Femenino , Degeneración Lobar Frontotemporal/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Fosforilación
15.
Acta Neuropathol ; 140(2): 121-142, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32562018

RESUMEN

Expansion of a (G4C2)n repeat in C9orf72 causes amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), but the link of the five repeat-encoded dipeptide repeat (DPR) proteins to neuroinflammation, TDP-43 pathology, and neurodegeneration is unclear. Poly-PR is most toxic in vitro, but poly-GA is far more abundant in patients. To directly compare these in vivo, we created congenic poly-GA and poly-PR mice. 40% of poly-PR mice were affected with ataxia and seizures, requiring euthanasia by 6 weeks of age. The remaining poly-PR mice were asymptomatic at 14 months of age, likely due to an 80% reduction of the transgene mRNA in this subgroup. In contrast, all poly-GA mice showed selective neuron loss, inflammation, as well as muscle denervation and wasting requiring euthanasia before 7 weeks of age. In-depth analysis of peripheral organs and blood samples suggests that peripheral organ failure does not drive these phenotypes. Although transgene mRNA levels were similar between poly-GA and affected poly-PR mice, poly-GA aggregated far more abundantly than poly-PR in the CNS and was also found in skeletal muscle. In addition, TDP-43 and other disease-linked RNA-binding proteins co-aggregated in rare nuclear inclusions in the hippocampus and frontal cortex only in poly-GA mice. Transcriptome analysis revealed activation of an interferon-responsive pro-inflammatory microglial signature in end-stage poly-GA but not poly-PR mice. This signature was also found in all ALS patients and enriched in C9orf72 cases. In summary, our rigorous comparison of poly-GA and poly-PR toxicity in vivo indicates that poly-GA, but not poly-PR at the same mRNA expression level, promotes interferon responses in C9orf72 disease and contributes to TDP-43 abnormalities and neuron loss selectively in disease-relevant regions.


Asunto(s)
Esclerosis Amiotrófica Lateral/genética , Proteína C9orf72/genética , Interferones/biosíntesis , Degeneración Nerviosa/patología , Esclerosis Amiotrófica Lateral/inmunología , Esclerosis Amiotrófica Lateral/patología , Animales , Expansión de las Repeticiones de ADN/genética , Modelos Animales de Enfermedad , Ratones , Ratones Transgénicos , Degeneración Nerviosa/genética , Degeneración Nerviosa/inmunología , Neuronas/patología
16.
Nanotechnology ; 31(19): 195202, 2020 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-32081838

RESUMEN

In this paper, we propose a miniaturized monolithic bandpass filter utilizing an air-filled half-mode waveguide and an inward curving split ring resonator array in the millimeter-wave band. The waveguide blocks the wave below cutoff frequency and the uniplanar array forms a rejection band above the transmission band. The microfabrication process of the filter adopts photoimageable technology and the combination of films with different thicknesses to build a 3D structure. The measured prototype has a center frequency at 65.5 GHz with a 3 dB fractional bandwidth of 30.7%. The minimum insertion loss is 2.1 dB. The proposed component offers excellent performance including a wide transmission band, a low pass-band insertion loss, an excellent isolation in the stop-band, and a steep roll-off at the upper cutoff frequency. Besides, due to the scalability of the waveguide and periodic array, this filter can be adapted for other frequency ranges.

17.
Med Mycol ; 57(5): 582-587, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-30380089

RESUMEN

To examine the relationship between Pneumocystis jirovecii DNA (PJ-DNA) levels in blood from AIDS-associated Pneumocystis pneumonia (AIDS-PCP) and mortality, and to correlate mitochondrial large subunit rRNA (mtLSUrRNA) gene polymorphism with mortality, we performed a retrospective study including AIDS-PCP patients between 2014 and 2016 from one hospital in China. PJ-DNA in plasma was measured by nested polymerase chain reaction (PCR) of the mtLSUrRNA gene and in positive specimens we further detected the level of PJ-DNA using qPCR. Polymorphisms were observed at two positions (85 and 248) of the mtLSUrRNA gene by sequencing. The PJ-DNA positivity rate for survivors and nonsurvivors was 13.64% (9/66) and 78.57% (11/14) (P ≤ .001), respectively. Using multivariate analysis, we found that lactate dehydrogenase, PaO2, albumin and PJ-positive in blood were independent predictors of death (P = .011; P = .042; P = .01; P ≤ .001, respectively). The PJ-DNA level in the nonsurvivor group (n = 11) was higher than that of the survivor group (n = 9) (54610.3copies/ ml vs. 934.5 copies/ml, P = .006). Nine had genotype 1, and 88.89% (8/9) patients died. Of nine with genotype 3, 11.11% (1/9) died (P = .003). In conclusion, high PJ-DNA level detected by analyzing plasma and mtLSUrRNA genotype 1 are strongly associated with death in AIDS-PCP patients.

18.
BMC Infect Dis ; 19(1): 223, 2019 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-30832615

RESUMEN

BACKGROUND: Indoleamine 2, 3-dioxygenase (IDO) is a key enzyme in the degradation of tryptophan (Trp) to kynurenine (Kyn). We measured IDO activity as the Kyn to Trp ratio, and investigated whether IDO could be used to assess prognosis of acquired immune deficiency Sydrome (AIDS) patients with pneumocystis pneumonia (PCP). METHODS: The Kyn and Trp concentration were measured by UPLC-MS/MS in plasma samples. A total of 49 AIDS-PCP patients were included in the analysis. Clinical characteristics and Kyn/Trp ratio were compared between survivors and non-survivors. RESULTS: Kyn/Trp ratio was significantly lower after anti-PCP treatment in AIDS patients with PCP (P < 0.0001). Plasma Kyn/Trp ratio was higher in patients with PaO2/FiO2 ≤ 300 mmHg than in those with PaO2/FiO2 > 300 mmHg (P = 0.007). Kyn/Trp ratio, D-dimer and CRP showed much higher AUC for predicting death of AIDS-PCP patients. Kyn/Trp ratio was useful for predicting the mortality of AIDS-PCP due to a significantly higher Kyn/Trp ratio in the non-survivors (P = 0.002). And the high Kyn/Trp ratio group had higher mortality rate than low Kyn/Trp group (32.1% vs. 9.1%, respectively, p = 0.024). CONCLUSION: Activation of the kynurenine pathway is associated with the severity and fatal outcomes of AIDS patients with pneumocystis pneumonia.


Asunto(s)
Infecciones por VIH/patología , Neumonía/diagnóstico , Adulto , Antifúngicos/uso terapéutico , Área Bajo la Curva , Biomarcadores/metabolismo , Cromatografía Líquida de Alta Presión , Estudios de Cohortes , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/mortalidad , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa/metabolismo , Quinurenina/análisis , Quinurenina/sangre , Masculino , Persona de Mediana Edad , Pneumocystis/aislamiento & purificación , Neumonía/complicaciones , Neumonía/tratamiento farmacológico , Neumonía/microbiología , Pronóstico , Curva ROC , Tasa de Supervivencia , Espectrometría de Masas en Tándem , Triptófano/análisis , Triptófano/sangre
19.
EMBO Rep ; 17(9): 1314-25, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27461252

RESUMEN

Intronic hexanucleotide (G4C2) repeat expansions in C9orf72 are genetically associated with frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS). The repeat RNA accumulates within RNA foci but is also translated into disease characterizing dipeptide repeat proteins (DPR). Repeat-dependent toxicity may affect nuclear import. hnRNPA3 is a heterogeneous nuclear ribonucleoprotein, which specifically binds to the G4C2 repeat RNA We now report that a reduction of nuclear hnRNPA3 leads to an increase of the repeat RNA as well as DPR production and deposition in primary neurons and a novel tissue culture model that reproduces features of the C9orf72 pathology. In fibroblasts derived from patients carrying extended C9orf72 repeats, nuclear RNA foci accumulated upon reduction of hnRNPA3. Neurons in the hippocampus of C9orf72 patients are frequently devoid of hnRNPA3. Reduced nuclear hnRNPA3 in the hippocampus of patients with extended C9orf72 repeats correlates with increased DPR deposition. Thus, reduced hnRNPA3 expression in C9orf72 cases leads to increased levels of the repeat RNA as well as enhanced production and deposition of DPR proteins and RNA foci.


Asunto(s)
Dipéptidos/metabolismo , Regulación de la Expresión Génica , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B/metabolismo , Proteínas/genética , ARN Mensajero/genética , Animales , Encéfalo/metabolismo , Proteína C9orf72 , Fibroblastos , Técnicas de Silenciamiento del Gen , Células HeLa , Humanos , Neuronas/metabolismo , Unión Proteica , Transporte de Proteínas , Células Piramidales/metabolismo , Transporte de ARN , ARN Interferente Pequeño/genética , Ratas
20.
Arch Virol ; 163(6): 1463-1468, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29435709

RESUMEN

BK polyomavirus (BKPyV) is an opportunistic infectious pathogen that is associated with hemorrhagic cystitis and nephropathy, mainly in transplant recipients and human immunodeficiency virus 1 (HIV-1) infected patients. However, molecular characterization studies of BKPyV in China are rare. This study was designed to elucidate the prevalence and to determine the main subtypes of BKPyV among HIV-1-infected patients in southeastern China. In addition, the increased incidences for BKPyV reactivation were analyzed. The isolated BKPyV DNA was amplified by polymerase chain reaction (PCR) and the specimen sequences were aligned with the reference sequences for phylogenetic analysis. In this study, BKPyV viruria was detected in 64.2% (88/137) of HIV-1-infected patients. Patients in the BKPyV-positive group were more diverse with respect to gender (P = 0.039) and age (P = 0.023) than their counterparts in the BKPyV-negative group, and they had a higher rate of co-infection with tuberculosis (TB) (P = 0.026). Viruria was more commonly found in patients with CD4 counts <200 cells/mm (72.7%) than in those with CD4 counts ≥200 cells/mm (58.5%) (not significant). All sequenced BKPyV isolates belonged to subtype I (13/32) and IV (19/32). A high prevalence of BKPyV reactivation was discovered in patients with HIV-1 infection. Females and elderly individuals, as well as those with a TB co-infection, appeared more susceptible to BKPyV reactivation in this study. BKPyV viruria was found more often and was associated with lower CD4 counts.


Asunto(s)
Virus BK/clasificación , ADN Viral/genética , Infecciones por VIH/epidemiología , Infecciones por Polyomavirus/epidemiología , Tuberculosis Pulmonar/epidemiología , Infecciones Tumorales por Virus/epidemiología , Adulto , Virus BK/genética , Virus BK/aislamiento & purificación , China/epidemiología , Coinfección , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/virología , VIH-1/genética , VIH-1/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/aislamiento & purificación , Filogenia , Infecciones por Polyomavirus/diagnóstico , Infecciones por Polyomavirus/virología , Prevalencia , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/microbiología , Infecciones Tumorales por Virus/diagnóstico , Infecciones Tumorales por Virus/virología , Orina/virología , Carga Viral , Activación Viral
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