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1.
Heliyon ; 10(7): e28730, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38586336

RESUMO

Background: Metamycoplasma orale (M.orale), a symbiotic bacterium observed in the human oral cavity, is generally regarded as non-pathogenic to humans. Although infrequent, symptomatic infections caused by M.orale may occur in individuals with compromised humoral immunity. Accurate identification and early diagnosis of M.orale still present significant challenges due the limitations associated with conventional detection methods. Although metagenomic next-generation sequencing (mNGS) is currently widely utilized in clinical practices and exhibits a remarkable specificity and sensitivity for detecting various pathogens, its application in the diagnosis of M.orale-induced osteomyelitis remains largely unexplored. Case description: In this report, we present a case study of osteonecrosis caused by M.orale in a 20-year-old female patient with nephrotic syndrome and other comorbidities. She was administered long-term hormone therapy and immunosuppressants, leading to her admission to the hospital due to recurrent fever, hip abscess and left thigh pain. Imaging examination revealed bilateral mid-femoral lesions, with the extensive nature of the left femoral lesion suggesting a potential secondary infection. Although no pathogen was detected in pus culture, mNGS analysis identified M.orale in the sample. Following treatment with doxycycline and levofloxacin, the patient's symotoms improved and she was discharged with favorable outcomes. Conclusion: mNGS enables rapid identification of etiology in patients with osteomyelitis caused by the rare pathogen M.orale. This case accentuate the strength of mNGS for early detection and targeted clinical treatment of infectious diseases caused by uncommon pathogens.

2.
Ann Clin Microbiol Antimicrob ; 23(1): 22, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424544

RESUMO

BACKGROUND: Early and accurate etiological diagnosis is very important for improving the prognosis of central nervous system (CNS) infections in human immunodeficiency virus (HIV)-infected patients. The goal is not easily achieved by conventional microbiological tests. We developed a nanopore targeted sequencing (NTS) platform and evaluated the diagnostic performance for CNS infections in HIV-infected patients, with special focus on cryptococcal meningitis (CM). We compared the CM diagnostic performance of NTS with conventional methods and cryptococcal polymerase chain reaction (PCR). METHODS: This study included 57 hospitalized HIV-infected patients with suspected CNS infections from September 2018 to March 2022. The diagnosis established during hospitalization includes 27 cases of CM, 13 CNS tuberculosis, 5 toxoplasma encephalitis, 2 cytomegalovirus (CMV) encephalitis and 1 Varicella-zoster virus (VZV) encephalitis. The 2 cases of CMV encephalitis also have co-existing CM. Target-specific PCR amplification was used to enrich pathogen sequences before nanopore sequencing. NTS was performed on stored cerebrospinal fluid (CSF) samples and the results were compared with the diagnosis during hospitalization. RESULTS: 53 (93.0%) of the patients were male. The median CD4 cell count was 25.0 (IQR: 14.0-63.0) cells/uL. The sensitivities of CSF culture, India ink staining, cryptococcal PCR and NTS for CM were 70.4% (95%CI: 51.5 - 84.1%), 76.0% (95%CI: 56.6 - 88.5%), 77.8% (59.2 - 89.4%) and 85.2% (95%CI: 67.5 - 94.1%), respectively. All those methods had 100% specificity for CM. Our NTS platform could identify Cryptococcus at species level. Moreover, NTS was also able to identify all the 5 cases of toxoplasma encephalitis, 2 cases of CMV encephalitis and 1 VZV encephalitis. However, only 1 of 13 CNS tuberculosis cases was diagnosed by NTS, and so did Xpert MTB/RIF assay. CONCLUSIONS: NTS has a good diagnostic performance for CM in HIV-infected patients and may have the ability of simultaneously detecting other pathogens, including mixed infections. With continuing improving of the NTS platform, it may be a promising alterative microbiological test for assisting with the diagnosis of CNS infections.


Assuntos
Infecções do Sistema Nervoso Central , Infecções por Citomegalovirus , Encefalite , Infecções por HIV , Sequenciamento por Nanoporos , Nanoporos , Tuberculose , Humanos , Masculino , Feminino , HIV , DNA Viral , Herpesvirus Humano 3/genética , Infecções do Sistema Nervoso Central/diagnóstico , Infecções do Sistema Nervoso Central/complicações , Infecções por Citomegalovirus/diagnóstico , Infecções por HIV/complicações , Tuberculose/complicações
3.
Front Cell Infect Microbiol ; 13: 1082412, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37124032

RESUMO

Background: Strongyloides stercoralis (S. stercoralis) is a nematode that is widely distributed in the tropical and subtropical regions of the world and which can cause severe disseminated infection in immunocompromised individuals. However, strongyloidiasis, the disease caused by S. stercoralis, is difficult to diagnose because of its non-specific clinical presentation and the inadequate performance of conventional diagnostic methods. Case description: We report the case of a 75-year-old male patient with severe disseminated infection caused by S. stercoralis. The patient had a medical history of seasonal bronchitis and, as a consequence, had taken prednisone for many years. Initial clinical tests failed to detect any pathogens, but metagenomic next-generation sequencing (mNGS) resulted in the identification of S. stercoralis in the patient's bronchoalveolar lavage fluid (BALF) and blood. Subsequently, routine testing repeatedly detected nematode larvae in the patient's stool and sputum. Through a combination of mNGS results and clinical symptoms, the patient was finally diagnosed with severe disseminated infection caused by S. stercoralis. Conclusion: The clinical manifestations of disease caused by infection with S. stercoralis are not specific; therefore, early and accurate diagnosis is very important. mNGS can detect S. stercoralis even when it is present at only a low level. This case report supports the notion that mNGS is a valuable tool in the diagnosis of severe disseminated infections caused by S. stercoralis in immunocompromised patients.


Assuntos
Strongyloides stercoralis , Estrongiloidíase , Masculino , Animais , Humanos , Idoso , Strongyloides stercoralis/genética , Estrongiloidíase/diagnóstico , Escarro , Hospedeiro Imunocomprometido , Sequenciamento de Nucleotídeos em Larga Escala
4.
Pest Manag Sci ; 78(3): 1213-1226, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34839581

RESUMO

BACKGROUND: Bursaphelenchus xylophilus, the pinewood nematode, kills millions of pine trees worldwide every year, and causes enormous economic and ecological losses. Despite extensive research on population variation, there is little understanding of the population-wide variation spectrum in China. RESULTS: We sequenced an inbred B. xylophilus strain using Pacbio+Illumina+Bionano+Hi-C and generated a chromosome-level assembly (AH1) with six chromosomes of 77.1 Mb (chromosome N50: 12 Mb). The AH1 assembly shows very high continuity and completeness, and contains novel genes with potentially important functions compared with previous assemblies. Subsequently, we sequenced 181 strains from China and the USA and found ~7.8 million single nucleotide polymorphisms (SNPs). Analysis shows that the B. xylophilus population in China can be divided into geographically bounded subpopulations with severe cross-infection and potential migrations. In addition, distribution of B. xylophilus is dominated by temperature zones while geographically associated SNPs are mainly located on adaptation related GPCR gene families, suggesting the nematode has been evolving to adapt to different temperatures. A machine-learning based epidemic tracking method has been established to predict their geographical origins, which can be applied to any other species. CONCLUSION: Our study provides the community with the first high-quality chromosome-level assembly which includes a comprehensive catalogue of genetic variations. It provides insights into population structure and effective tracking method for this invasive species, which facilitates future studies to address a variety of applied, genomic and evolutionary questions in B. xylophilus as well as related species.


Assuntos
Genética Populacional , Pinus , Rabditídios , Animais , China , Cromossomos , Genoma Helmíntico , Pinus/parasitologia , Rabditídios/genética , Sequenciamento Completo do Genoma
5.
J Speech Lang Hear Res ; 63(11): 3571-3585, 2020 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-33090915

RESUMO

Purpose Research has shown that observing hand gestures mimicking pitch movements or rhythmic patterns can improve the learning of second language (L2) suprasegmental features. However, less is known about the effects of hand gestures on the learning of novel phonemic contrasts. This study examines (a) whether hand gestures mimicking phonetic features can boost L2 segment learning by naive learners and (b) whether a mismatch between the hand gesture form and the target phonetic feature influences the learning effect. Method Fifty Catalan native speakers undertook a short multimodal training session on two types of Mandarin Chinese consonants (plosives and affricates) in either of two conditions: Gesture and No Gesture. In the Gesture condition, a fist-to-open-hand gesture was used to mimic air burst, while the No Gesture condition included no such use of gestures. Crucially, while the hand gesture appropriately mimicked the air burst produced in plosives, this was not the case for affricates. Before and after training, participants were tested on two tasks, namely, the identification task and the imitation task. Participants' speech output was rated by five Chinese native speakers. Results The perception results showed that training with or without gestures yielded similar degrees of improvement for the identification of aspiration contrasts. By contrast, the production results showed that, while training without gestures did not help improve L2 pronunciation, training with gestures improved pronunciation, but only when the given gestures appropriately mimicked the phonetic properties they represented. Conclusions Results revealed that the efficacy of observing hand gestures on the learning of nonnative phonemes depends on the appropriateness of the form of those gestures relative to the target phonetic features. That is, hand gestures seem to be more useful when they appropriately mimic phonetic features. Supplemental Material https://doi.org/10.23641/asha.13105442.


Assuntos
Gestos , Fonética , Humanos , Idioma , Aprendizagem , Fala
6.
Adv Mater ; 31(40): e1903125, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31402540

RESUMO

Hard carbon is regarded as a promising anode material for sodium-ion batteries (SIBs). However, it usually suffers from the issues of low initial Coulombic efficiency (ICE) and poor rate performance, severely hindering its practical application. Herein, a flexible, self-supporting, and scalable hard carbon paper (HCP) derived from scalable and renewable tissue is rationally designed and prepared as practical additive-free anode for room/low-temperature SIBs with high ICE. In ether electrolyte, such HCP achieves an ICE of up to 91.2% with superior high-rate capability, ultralong cycle life (e.g., 93% capacity retention over 1000 cycles at 200 mA g-1 ) and outstanding low-temperature performance. Working mechanism analyses reveal that the plateau region is the rate-determining step for HCP with a lower electrochemical reaction kinetics, which can be significantly improved in ether electrolyte.

7.
Chem Commun (Camb) ; 55(58): 8406-8409, 2019 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-31257383

RESUMO

Metallic lithium protection plays a crucial role on improving the electrochemical properties of Li-anode-based batteries. Herein, for an advanced Li//graphite dual-ion battery, constructing a robust and conductive film of carbon nanofibers on a Li anode effectively achieves dendrite-free Li growth and hence significantly enhances the long-life cyclic stability.

8.
Nanoscale ; 11(3): 1304-1312, 2019 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-30603754

RESUMO

In order to develop promising anode materials for lithium-ion batteries (LIBs), a unique nanocomposite abbreviated as G⊥FP@C-NA, in which a carbon-coated FeP nanorod array (FP@C-NA) is vertically grown on a conductive reduced graphene oxide (G) network, has been successfully prepared via a scalable strategy. Benefiting from the distinctive structure, G⊥FP@C-NA exhibits much improved conductivity, structural stability and pseudocapacitance-boosted ultrafast electrochemical kinetics for Li storage. As a result, the G⊥FP@C-NA delivers a high Li-storage capacity (1106 mA h g-1 at 50 mA g-1), outstanding rate capability (565 mA h g-1 at 5000 mA g-1) and long-term cycling stability (1009 mA h g-1 at 500 mA g-1 after 500 cycles and 310 mA h g-1 at 2000 mA g-1 after 2000 cycles) when used as an anode material for LIBs. As expected, this kind of nanoarray structure is attractive and can also be extended to other electrode materials for various energy storage systems.

10.
Adv Mater ; 31(4): e1804766, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30489656

RESUMO

Conventional ion batteries utilizing metallic ions as the single charge carriers are limited by the insufficient abundance of metal resources. Although supercapacitors apply both cations and anions to store energy through absorption and/or Faradic reactions occurring at the interfaces of the electrode/electrolyte, the inherent low energy density hinders its application. The graphite-cathode-based dual-ion battery possesses a higher energy density due to its high working potential of nearly 5 V. However, such a battery configuration suffers from severe electrolyte decomposition and exfoliation of the graphite cathode, rendering an inferior cycle life. Herein, a new surface-modification strategy is developed to protect the graphite cathode from the anion salvation effect and the deposition derived from electrolyte decomposition by generating an artificial solid electrolyte interphase (SEI). Such SEI-modified graphite exhibits superior cycling stability with 96% capacity retention after 500 cycles under 200 mA g-1 at the upper cutoff voltage of 5.0 V, which is much improved compared with the pristine graphite electrode. Through several ex situ studies, it is revealed that the artificial SEI greatly stabilizes the interfaces of the electrode/electrolyte after reconstruction and gradual establishment of the optimal anion-transport path. The findings shed light on a new avenue toward promoting the performance of the dual-ion battery (DIB) and hence to make it practical finally.

11.
Nanoscale ; 10(19): 9218-9225, 2018 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-29726554

RESUMO

In order to develop promising anode materials for sodium-ion batteries (SIBs), a novel pie-like FeS@C (P-FeS@C) nanohybrid, in which all ultrasmall FeS nanocrystals (NCs) are completely embedded into the carbon network and sealed by a protective carbon shell, has been prepared. The unique pie-like structure can effectively speed up the kinetics of electrode reactions, while the carbon shell stabilizes the FeS NCs inside. Studies show that the electrochemical reaction processes of P-FeS@C electrodes are dominated by the pseudocapacitive behavior, leading to an ultrafast Na+-insertion/extraction reaction. Hence, the prepared P-FeS@C nanohybrid exhibits superior Na-storage properties especially high rate capability in half cells. For example, it can deliver reversible capacities of 555.1 mA h g-1 at 0.2 A g-1 over 150 cycles and about 60.4 mA h g-1 at 80 A g-1 (an ultrahigh current density even higher than that of the capacitor test). Furthermore, an advanced P-FeS@C//Na3V2(PO4)2O2F full cell has been assembled out, which delivers a stable specific capacity of 441.2 mA h g-1 after 80 cycles at 0.5 A g-1 with a capacity retention of 91.8%.

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